id
stringlengths 9
14
| submitter
stringlengths 1
56
⌀ | authors
stringlengths 5
7.68k
| title
stringlengths 3
299
| comments
stringlengths 1
1.15k
⌀ | journal-ref
stringlengths 9
298
⌀ | doi
stringlengths 12
97
⌀ | report-no
stringlengths 3
341
⌀ | categories
stringclasses 869
values | license
stringclasses 9
values | orig_abstract
stringlengths 16
2.44k
| versions
listlengths 1
39
| update_date
stringlengths 10
10
| authors_parsed
listlengths 1
565
| abstract
stringlengths 13
2.44k
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/9910466
|
Chaehyun Yu
|
Kang Young Lee, Seong Chan Park, H. S. Song, Jeonhyeon Song, and
Chaehyun Yu
|
Spin configuration of top quark pair production with large extra
dimensions at photon-photon colliders
|
18 pages, 4 figures, ReVTeX
|
Phys.Rev. D61 (2000) 074005
|
10.1103/PhysRevD.61.074005
|
SNUTP 99-047
|
hep-ph
| null |
Top quark pair production at photon-photon colliders is studied in low scale
quantum gravity scenario. From the dependence of the cross sections on the spin
configuration of the top quark and anti-quark, we introduce a new observable,
top spin asymmetry. It is shown that there exists a special top spin basis
where with the polarized parent electron beams the top spin asymmetry vanishes
in the standard model but retains substantial values with the large extra
dimension effects. We also present lower bounds of the quantum gravity scale
$M_S$ from total cross sections with various combinations of the laser,
electron beam, and top quark pair polarizations. The measurements of the top
spin state $(t_\uparrow\bar{t}_\downarrow)$ with unpolarized initial beams are
shown to be most effective, enhancing by about 5% the $M_S$ bounds with respect
to totally unpolarized case.
|
[
{
"created": "Mon, 25 Oct 1999 03:25:05 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Lee",
"Kang Young",
""
],
[
"Park",
"Seong Chan",
""
],
[
"Song",
"H. S.",
""
],
[
"Song",
"Jeonhyeon",
""
],
[
"Yu",
"Chaehyun",
""
]
] |
Top quark pair production at photon-photon colliders is studied in low scale quantum gravity scenario. From the dependence of the cross sections on the spin configuration of the top quark and anti-quark, we introduce a new observable, top spin asymmetry. It is shown that there exists a special top spin basis where with the polarized parent electron beams the top spin asymmetry vanishes in the standard model but retains substantial values with the large extra dimension effects. We also present lower bounds of the quantum gravity scale $M_S$ from total cross sections with various combinations of the laser, electron beam, and top quark pair polarizations. The measurements of the top spin state $(t_\uparrow\bar{t}_\downarrow)$ with unpolarized initial beams are shown to be most effective, enhancing by about 5% the $M_S$ bounds with respect to totally unpolarized case.
|
2201.05851
|
Liangliang Liu
|
Liang-Liang Liu, Su-Jun Cui, Jing Xu, Xin-Heng Guo
|
Forward-backward asymmetries in $\Lambda_b \rightarrow \Lambda l^+ l^-$
in Bethe-Salpeter equation approach
| null |
chinese physics c 2022, 46(9): 093106
|
10.1088/1674-1137/ac7041
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Using the Bethe-Salpeter equation (BSE) we investigate the forward-backward
asymmetries $( A_{FB}) $ in $\Lambda_b \rightarrow \Lambda l^+
l^-(l=e,\mu,\tau)$ in the quark-diquark model. This approach provides precise
form factors that are different from those of QCD sum rules. We calculate the
rare decay form factors for $\Lambda_b \rightarrow \Lambda l^+ l^-$ and
investigate the (integrated) forward-backward asymmetries in these decay
channels. We find that the integrated $A^l_{FB}$, $\bar{A}^l_{FB}(\Lambda_b
\rightarrow \Lambda e^+ e^-) \simeq -0.1371 $, $\bar{A}^l_{FB}(\Lambda_b
\rightarrow \Lambda \mu^+ \mu^- ) \simeq -0.1376 $, $\bar{A}^l_{FB}(\Lambda_b
\rightarrow \Lambda \tau^+ \tau^-) \simeq -0.1053 $, the hadron side
asymmetries $\bar{A}^h_{FB}(\Lambda_b \rightarrow \Lambda \mu^+ \mu^-)\simeq
-0.2315$, the lepton-hadron side asymmetries $\bar{A}^{lh}_{FB}(\Lambda_b
\rightarrow \Lambda \mu^+ \mu^-)\simeq 0.0827$, the longitudinal polarization
fractions $\bar{F}_L(\Lambda_b \rightarrow \Lambda \mu^+ \mu^-)\simeq 0.5681$.
|
[
{
"created": "Sat, 15 Jan 2022 13:50:56 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Apr 2022 13:16:34 GMT",
"version": "v2"
},
{
"created": "Mon, 9 May 2022 12:06:37 GMT",
"version": "v3"
}
] |
2022-08-29
|
[
[
"Liu",
"Liang-Liang",
""
],
[
"Cui",
"Su-Jun",
""
],
[
"Xu",
"Jing",
""
],
[
"Guo",
"Xin-Heng",
""
]
] |
Using the Bethe-Salpeter equation (BSE) we investigate the forward-backward asymmetries $( A_{FB}) $ in $\Lambda_b \rightarrow \Lambda l^+ l^-(l=e,\mu,\tau)$ in the quark-diquark model. This approach provides precise form factors that are different from those of QCD sum rules. We calculate the rare decay form factors for $\Lambda_b \rightarrow \Lambda l^+ l^-$ and investigate the (integrated) forward-backward asymmetries in these decay channels. We find that the integrated $A^l_{FB}$, $\bar{A}^l_{FB}(\Lambda_b \rightarrow \Lambda e^+ e^-) \simeq -0.1371 $, $\bar{A}^l_{FB}(\Lambda_b \rightarrow \Lambda \mu^+ \mu^- ) \simeq -0.1376 $, $\bar{A}^l_{FB}(\Lambda_b \rightarrow \Lambda \tau^+ \tau^-) \simeq -0.1053 $, the hadron side asymmetries $\bar{A}^h_{FB}(\Lambda_b \rightarrow \Lambda \mu^+ \mu^-)\simeq -0.2315$, the lepton-hadron side asymmetries $\bar{A}^{lh}_{FB}(\Lambda_b \rightarrow \Lambda \mu^+ \mu^-)\simeq 0.0827$, the longitudinal polarization fractions $\bar{F}_L(\Lambda_b \rightarrow \Lambda \mu^+ \mu^-)\simeq 0.5681$.
|
1808.06828
|
Vincenzo Afferrante
|
Vincenzo Afferrante, Guido Martinelli
|
Study of Anomalies in Exclusive Semileptonic B Decays
|
7 pages, 4 figures, An Alpine LHC Physics Summit (ALPS2018) - Young
Scientist Forum Proceedings
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Our Vcb extraction is based on recent Belle results, with unfolded
kinematical dependence. We use two different parameterizations of the form
factors, the CLN and BGL parameterizations. We discuss how the known
discrepancy between the inclusive and exclusive determinations of Vcb depends
on an underestimate of the uncertainty with parameterizations that use heavy
quark expansion.
We investigate the results of the semileptonic B decay with heavy leptons
(tau) compared to the decays into light leptons. Experimental ratio of the two
branching ratios is systematically larger than the Standard Model(SM)
prediction. Effects of new physics operators on the data about these decays are
studied.
|
[
{
"created": "Tue, 21 Aug 2018 10:08:31 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Aug 2018 09:50:29 GMT",
"version": "v2"
}
] |
2018-08-27
|
[
[
"Afferrante",
"Vincenzo",
""
],
[
"Martinelli",
"Guido",
""
]
] |
Our Vcb extraction is based on recent Belle results, with unfolded kinematical dependence. We use two different parameterizations of the form factors, the CLN and BGL parameterizations. We discuss how the known discrepancy between the inclusive and exclusive determinations of Vcb depends on an underestimate of the uncertainty with parameterizations that use heavy quark expansion. We investigate the results of the semileptonic B decay with heavy leptons (tau) compared to the decays into light leptons. Experimental ratio of the two branching ratios is systematically larger than the Standard Model(SM) prediction. Effects of new physics operators on the data about these decays are studied.
|
hep-ph/0603060
|
Mikhail Braun
|
M.A.Braun
|
On the inclusive gluon jet production from the triple pomeron vertex in
the perturbative QCD
|
17 pages in LaTex, 6 figures, revised version with partially changed
rsults
|
Eur.Phys.J.C48:501-510,2006
|
10.1140/epjc/s10052-006-0030-8
| null |
hep-ph
| null |
Single and double inclusive cross-sections for gluon jet production from
within the triple pomeron vertex are studied in the reggeized gluon technique.
It is shown that to satisfy the AGK rules the vertex has to be fully symmetric
in all four reggeized gluons which form the two final pomerons. The single
inclusive cross-sections are found for different cuttings of the triple pomeron
vertex. They sum into the expression obtained by Yu.Kovchegov and K.Tuchin in
the colour dipole picture. The found double inclusive cross-sections satisfy
the AGK rules.
|
[
{
"created": "Wed, 8 Mar 2006 06:18:05 GMT",
"version": "v1"
},
{
"created": "Wed, 31 May 2006 16:12:55 GMT",
"version": "v2"
}
] |
2011-09-13
|
[
[
"Braun",
"M. A.",
""
]
] |
Single and double inclusive cross-sections for gluon jet production from within the triple pomeron vertex are studied in the reggeized gluon technique. It is shown that to satisfy the AGK rules the vertex has to be fully symmetric in all four reggeized gluons which form the two final pomerons. The single inclusive cross-sections are found for different cuttings of the triple pomeron vertex. They sum into the expression obtained by Yu.Kovchegov and K.Tuchin in the colour dipole picture. The found double inclusive cross-sections satisfy the AGK rules.
|
2211.04941
|
Shi-Ping He
|
Shi-Ping He
|
Leptoquark and vectorlike quark extended models as the explanation of
$(g-2)_{\mu}$ anomaly
|
6 pages, 1 captioned figure, 4 tables. Based on the paper
arXiv:2112.13490 [hep-ph]. Online talk presented at the 41st International
Conference on High Energy Physics - ICHEP2022 (6-13 July, 2022, Bologna,
Italy). Accepted for publication in Proceedings of Science
|
PoS ICHEP2022 (2022) 137
|
10.22323/1.414.0137
| null |
hep-ph hep-ex
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
In minimal leptoquark (LQ) models, the $R_2$ and $S_1$ can be the solution to
the $(g-2)_{\mu}$ anomaly because of the chiral enhancements. Here, we study
the LQ and vectorlike quark (VLQ) extended models. In the one LQ and one VLQ
extended models, the $(g-2)_{\mu}$ can receive the contributions from top and
top partner $T$ because of the $t-T$ mixing. Besides the traditional $R_2$ and
$S_1$ representations, we find that the $S_3$ LQ can also explain the anomaly
when including the $(X,T,B)_{L,R}$ triplet at the same time. Moreover, we find
that the LQ has the new decay channel $T\mu$ in these models.
|
[
{
"created": "Wed, 9 Nov 2022 15:08:08 GMT",
"version": "v1"
}
] |
2022-11-28
|
[
[
"He",
"Shi-Ping",
""
]
] |
In minimal leptoquark (LQ) models, the $R_2$ and $S_1$ can be the solution to the $(g-2)_{\mu}$ anomaly because of the chiral enhancements. Here, we study the LQ and vectorlike quark (VLQ) extended models. In the one LQ and one VLQ extended models, the $(g-2)_{\mu}$ can receive the contributions from top and top partner $T$ because of the $t-T$ mixing. Besides the traditional $R_2$ and $S_1$ representations, we find that the $S_3$ LQ can also explain the anomaly when including the $(X,T,B)_{L,R}$ triplet at the same time. Moreover, we find that the LQ has the new decay channel $T\mu$ in these models.
|
2406.00651
|
Oleg Popov
|
Takaaki Nomura and Oleg Popov
|
Extended Scotogenic Model of Neutrino Mass and Proton Decay
|
9 pages, 7 figures, submitted to PRD
| null | null | null |
hep-ph hep-ex
|
http://creativecommons.org/licenses/by/4.0/
|
The current article presents an extension of the classical scotogenic
neutrino mass paradigm, where the three issues in particle physics: dark
matter, smallness of neutrino mass, and stability of the proton are
interconnected. The scenario encompasses the neutrino mass as well as the
proton decay as a consequence of an existence of the dark matter. The study
successfully achieves the correlation between the naturally small neutrino
masses and naturally long proton lifetime in the present paradigm. Furthermore,
all relevant cosmological, collider, and flavor physics constraints are
incorporated in the detailed analysis. The scotogenic fermionic dark matter
with the mass in the range from $100$ GeV to $10$ TeV successfully satisfies
all relevant constraints. The valid range of $2.51\times 10^{-5} < \lambda <
2\times 10^{-3}$ is obtained for the 2HDM $\lambda$ coupling. We give a brief
discussion, as well as, outline some of the future prospects.
|
[
{
"created": "Sun, 2 Jun 2024 07:39:11 GMT",
"version": "v1"
}
] |
2024-06-04
|
[
[
"Nomura",
"Takaaki",
""
],
[
"Popov",
"Oleg",
""
]
] |
The current article presents an extension of the classical scotogenic neutrino mass paradigm, where the three issues in particle physics: dark matter, smallness of neutrino mass, and stability of the proton are interconnected. The scenario encompasses the neutrino mass as well as the proton decay as a consequence of an existence of the dark matter. The study successfully achieves the correlation between the naturally small neutrino masses and naturally long proton lifetime in the present paradigm. Furthermore, all relevant cosmological, collider, and flavor physics constraints are incorporated in the detailed analysis. The scotogenic fermionic dark matter with the mass in the range from $100$ GeV to $10$ TeV successfully satisfies all relevant constraints. The valid range of $2.51\times 10^{-5} < \lambda < 2\times 10^{-3}$ is obtained for the 2HDM $\lambda$ coupling. We give a brief discussion, as well as, outline some of the future prospects.
|
0809.4158
|
Gleb Fedotov V
|
Viktor Mokeev, Volker Burkert, Tsung-Shung H. Lee, Latifa Elouadrhiri,
Gleb Fedotov, Boris Ishkhanov
|
Model Analysis of the $ep \to ep'\pi^+\pi^-$ Electroproduction Reaction
on the Proton
|
Experiment Numbers: E93-006, E94-005 Group: Hall B
|
Phys.Rev.C80:045212,2009
|
10.1103/PhysRevC.80.045212
|
JLAB-PHY-08-882
|
hep-ph nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Recent CLAS data on the $p\pi^+\pi^-$ electroproduction off protons at
1.3$<$W$<$1.57 GeV and 0.25$<$$Q^{2}$$<$0.6 GeV$^{2}$ have been analyzed using
a meson-baryon phenomenological model. By fitting nine 1-fold differential
cross section data for each $W$ and $Q^{2}$ bin, the charged double pion
electroproduction mechanisms are identified from their manifestations in the
observables. We have extracted the cross sections from amplitudes of each of
the considered isobar channels as well as from their coherent sum. We also
obtained non-resonant partial wave amplitudes of all contributing isobar
channels which could be useful for advancing a complete coupled-channel
analysis of all meson electroproduction data.
|
[
{
"created": "Wed, 24 Sep 2008 14:50:12 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Sep 2008 22:59:29 GMT",
"version": "v2"
},
{
"created": "Sat, 27 Sep 2008 21:25:02 GMT",
"version": "v3"
},
{
"created": "Mon, 17 Aug 2009 20:55:25 GMT",
"version": "v4"
}
] |
2009-11-06
|
[
[
"Mokeev",
"Viktor",
""
],
[
"Burkert",
"Volker",
""
],
[
"Lee",
"Tsung-Shung H.",
""
],
[
"Elouadrhiri",
"Latifa",
""
],
[
"Fedotov",
"Gleb",
""
],
[
"Ishkhanov",
"Boris",
""
]
] |
Recent CLAS data on the $p\pi^+\pi^-$ electroproduction off protons at 1.3$<$W$<$1.57 GeV and 0.25$<$$Q^{2}$$<$0.6 GeV$^{2}$ have been analyzed using a meson-baryon phenomenological model. By fitting nine 1-fold differential cross section data for each $W$ and $Q^{2}$ bin, the charged double pion electroproduction mechanisms are identified from their manifestations in the observables. We have extracted the cross sections from amplitudes of each of the considered isobar channels as well as from their coherent sum. We also obtained non-resonant partial wave amplitudes of all contributing isobar channels which could be useful for advancing a complete coupled-channel analysis of all meson electroproduction data.
|
1311.6160
|
Andrej Ficnar
|
Andrej Ficnar, Steven S. Gubser, Miklos Gyulassy
|
Shooting String Holography of Jet Quenching at RHIC and LHC
|
10 pages, 5 figures. Added references and two appendices. Several
claims clarified and other minor corrections. Published version
|
Phys.Lett. B738 (2014) 464-471
|
10.1016/j.physletb.2014.10.016
|
PUPT-2455
|
hep-ph hep-th nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We derive a new formula for jet energy loss using finite endpoint momentum
shooting strings initial conditions in SYM plasmas to overcome the difficulties
of previous falling string holographic scenarios. We apply the new formula to
compute the nuclear modification factor RAA and the elliptic flow parameter v2
of light hadrons at RHIC and LHC. We show furthermore that Gauss-Bonnet
quadratic curvature corrections to the AdS5 geometry improve the agreement with
the recent data.
|
[
{
"created": "Sun, 24 Nov 2013 19:46:35 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Nov 2014 18:25:42 GMT",
"version": "v2"
}
] |
2014-11-10
|
[
[
"Ficnar",
"Andrej",
""
],
[
"Gubser",
"Steven S.",
""
],
[
"Gyulassy",
"Miklos",
""
]
] |
We derive a new formula for jet energy loss using finite endpoint momentum shooting strings initial conditions in SYM plasmas to overcome the difficulties of previous falling string holographic scenarios. We apply the new formula to compute the nuclear modification factor RAA and the elliptic flow parameter v2 of light hadrons at RHIC and LHC. We show furthermore that Gauss-Bonnet quadratic curvature corrections to the AdS5 geometry improve the agreement with the recent data.
|
2307.02533
|
Hakan Akdag
|
Hakan Akdag, Bastian Kubis, Andreas Wirzba
|
Correlations of $C$ and $CP$ violation in $\eta\to \pi^0\ell^+\ell^-$
and $\eta'\to \eta\ell^+\ell^-$
|
35 pages, 7 figures, 3 tables; v2: section 5 revised, discussion
extended, version published in JHEP
|
JHEP 03 (2024) 059
|
10.1007/JHEP03(2024)059
| null |
hep-ph hep-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Based on recent progress in the systematic analysis of $C$ and $CP$ violation
in the light-meson sector, we calculate the $C$-odd transition amplitudes
$\eta\to\pi^0\ell^+\ell^-$ and $\eta'\to\eta\ell^+\ell^-$. Focusing on
long-distance contributions driven by the lowest-lying hadronic intermediate
states, we work out the correlations between these beyond-the-Standard-Model
signals and the Dalitz-plot asymmetries in $\eta \rightarrow \pi^0 \pi^+ \pi^-$
and $\eta' \rightarrow \eta \pi^+ \pi^- $, using dispersion theory.
|
[
{
"created": "Wed, 5 Jul 2023 18:00:01 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Mar 2024 20:28:33 GMT",
"version": "v2"
}
] |
2024-03-19
|
[
[
"Akdag",
"Hakan",
""
],
[
"Kubis",
"Bastian",
""
],
[
"Wirzba",
"Andreas",
""
]
] |
Based on recent progress in the systematic analysis of $C$ and $CP$ violation in the light-meson sector, we calculate the $C$-odd transition amplitudes $\eta\to\pi^0\ell^+\ell^-$ and $\eta'\to\eta\ell^+\ell^-$. Focusing on long-distance contributions driven by the lowest-lying hadronic intermediate states, we work out the correlations between these beyond-the-Standard-Model signals and the Dalitz-plot asymmetries in $\eta \rightarrow \pi^0 \pi^+ \pi^-$ and $\eta' \rightarrow \eta \pi^+ \pi^- $, using dispersion theory.
|
hep-ph/9509424
|
Steve Mrenna
|
S. Mrenna (Argonne) and C.-P. Yuan (Michigan State Univ.)
|
Detecting a Light Stop from Top Decays at the Tevatron
|
12 pages with 1 Postscript figure using psfig.sty. Postscript file
available at http://sgi2.hep.anl.gov:8001/index.html
|
Phys.Lett.B367:188-194,1996
|
10.1016/0370-2693(95)01431-4
|
ANL-HEP-PR-95-66 and MSUHEP-50925
|
hep-ph
| null |
We study the possibility of discovering or excluding a light top squark
(stop) based on top quark decays in the t-tbar events produced at the Fermilab
Tevatron. In particular, we consider the Minimal Supersymmetric Standard Model
with the sparticle spectrum m_{chi^+_1}+m_b, M_W+m_{chi^0_1}+m_b > m_{stop} >
m_{chi^0_1}+m_c, where chi^0_1 is the lightest neutralino and chi^+_1 is the
lightest chargino, so that t -> stop chi^0_1 and stop -> c chi^0_1. All other
sparticle masses are assumed to be heavier than m_t. Such a spectrum seeks to
explain the experimental values of alpha_s(M_Z^2), R_b and A_{LR} obtained from
LEP/SLC data. We find that the prospect to observe a light stop via this
channel at the Tevatron is very promising.
|
[
{
"created": "Fri, 29 Sep 1995 19:03:43 GMT",
"version": "v1"
}
] |
2014-11-17
|
[
[
"Mrenna",
"S.",
"",
"Argonne"
],
[
"Yuan",
"C. -P.",
"",
"Michigan State Univ."
]
] |
We study the possibility of discovering or excluding a light top squark (stop) based on top quark decays in the t-tbar events produced at the Fermilab Tevatron. In particular, we consider the Minimal Supersymmetric Standard Model with the sparticle spectrum m_{chi^+_1}+m_b, M_W+m_{chi^0_1}+m_b > m_{stop} > m_{chi^0_1}+m_c, where chi^0_1 is the lightest neutralino and chi^+_1 is the lightest chargino, so that t -> stop chi^0_1 and stop -> c chi^0_1. All other sparticle masses are assumed to be heavier than m_t. Such a spectrum seeks to explain the experimental values of alpha_s(M_Z^2), R_b and A_{LR} obtained from LEP/SLC data. We find that the prospect to observe a light stop via this channel at the Tevatron is very promising.
|
1504.01286
|
Junfeng Sun
|
Junfeng Sun, Na Wang, Qin Chang and Yueling Yang
|
$B_{c}$ ${\to}$ $BP$, $BV$ decays with the QCD factorization approach
|
15 pages, revtex4, version appeared in Advances in High Energy
Physics
|
Advances in High Energy Physics, 2015, 104378
|
10.1155/2015/104378
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We studied the nonleptonic $B_{c}$ ${\to}$ $BP$, $BV$ decay with the QCD
factorization approach. It is found that the Cabibbo favored processes of
$B_{c}$ ${\to}$ $B_{s}{\pi}$, $B_{s}{\rho}$, $B_{u}\bar{K}$ are the promising
decay channels with branching ratio larger than 1\%, which should be observed
earlier by the LHCb Collaboration.
|
[
{
"created": "Mon, 6 Apr 2015 14:21:09 GMT",
"version": "v1"
}
] |
2015-04-07
|
[
[
"Sun",
"Junfeng",
""
],
[
"Wang",
"Na",
""
],
[
"Chang",
"Qin",
""
],
[
"Yang",
"Yueling",
""
]
] |
We studied the nonleptonic $B_{c}$ ${\to}$ $BP$, $BV$ decay with the QCD factorization approach. It is found that the Cabibbo favored processes of $B_{c}$ ${\to}$ $B_{s}{\pi}$, $B_{s}{\rho}$, $B_{u}\bar{K}$ are the promising decay channels with branching ratio larger than 1\%, which should be observed earlier by the LHCb Collaboration.
|
0709.3952
|
Yudi Santoso
|
Yudi Santoso
|
Gravitino Dark Matter with Stop as the NLSP
|
Submitted for the SUSY07 proceedings
| null | null | null |
hep-ph
| null |
Gravitino is one feasible candidate for the dark matter in supergravity
models. With its couplings being suppressed by the Plank mass, gravitino
interacts very weakly with other particles, making its direct detection, or
production at colliders practically impossible. The signatures of this scenario
mainly arise from the next lightest supersymmetric particle (NLSP) which is
metastable due to the very weak coupling. There are many possibilities for the
NLSP, and here I will review the feasibility of stop particle as the NLSP and
discuss its phenomenology.
|
[
{
"created": "Tue, 25 Sep 2007 14:00:12 GMT",
"version": "v1"
}
] |
2007-09-26
|
[
[
"Santoso",
"Yudi",
""
]
] |
Gravitino is one feasible candidate for the dark matter in supergravity models. With its couplings being suppressed by the Plank mass, gravitino interacts very weakly with other particles, making its direct detection, or production at colliders practically impossible. The signatures of this scenario mainly arise from the next lightest supersymmetric particle (NLSP) which is metastable due to the very weak coupling. There are many possibilities for the NLSP, and here I will review the feasibility of stop particle as the NLSP and discuss its phenomenology.
|
hep-ph/9905302
|
Michael Bordag
|
Vladimir Skalozub and Michael Bordag
|
Once More on a Colour Ferromagnetic Vacuum State at Finite Temperature
|
16 pages, 2 figures, subm. to Nucl. Phys. B
|
Nucl.Phys. B576 (2000) 430-444
|
10.1016/S0550-3213(00)00101-2
| null |
hep-ph
| null |
The spontaneous vacuum magnetization at finite temperature is investigated in
SU(2) gluodynamics within a consistent effective potential approach including
the one-loop and the correlation correction contributions. To evaluate the
latter ones the high temperature limits of the polarization operators of
charged and neutral gluon fields in a covariantly constant magnetic field and
at high temperature are calculated.The radiation mass squared of charged gluons
is found to be positive. It is shown that the ferromagnetic vacuum state having
a field strength of order $(gH)^{1/2} \sim g^{4/3} T$ is spontaneously
generated at high temperature. The vacuum stability and some applications of
the results obtained are discussed.
|
[
{
"created": "Tue, 11 May 1999 12:24:34 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Skalozub",
"Vladimir",
""
],
[
"Bordag",
"Michael",
""
]
] |
The spontaneous vacuum magnetization at finite temperature is investigated in SU(2) gluodynamics within a consistent effective potential approach including the one-loop and the correlation correction contributions. To evaluate the latter ones the high temperature limits of the polarization operators of charged and neutral gluon fields in a covariantly constant magnetic field and at high temperature are calculated.The radiation mass squared of charged gluons is found to be positive. It is shown that the ferromagnetic vacuum state having a field strength of order $(gH)^{1/2} \sim g^{4/3} T$ is spontaneously generated at high temperature. The vacuum stability and some applications of the results obtained are discussed.
|
1911.05021
|
Sushant Raut
|
Soumya C., Monojit Ghosh, Sushant K. Raut, Nita Sinha, Poonam Mehta
|
Probing muonic charged current nonstandard interactions at decay-at-rest
facilities in conjunction with T2HK
|
Matches version published in Phys. Rev. D
|
Phys. Rev. D 101, 055009 (2020)
|
10.1103/PhysRevD.101.055009
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The muon decay-at-rest ($\mu$-DAR) facility provides us with an ideal
platform to probe purely muonic charged-current nonstandard neutrino
interactions (NSIs). We propose to probe this class of NSI effects using
antineutrinos from a $\mu$-DAR source in conjunction with neutrinos from the
future Tokai to Kamioka superbeam experiment with megaton Hyper Kamiokande
detector (T2HK). Even though muonic NSIs are absent in neutrino production at
T2HK, we show that our proposed hybrid setup comprising $\mu$-DAR and T2HK
helps in alleviating the parameter degeneracies that can arise in data.
Analytic considerations reveal that the oscillation probability is most
sensitive to the NSI parameter in the $\mu$-e sector. For this parameter, we
show that the $\mu$-DAR setup can improve on the existing bounds down to around
0.01, especially when the data are combined with neutrino data from T2HK
experiment due to the lifting of parameter degeneracies. The high precision
with which $\mu$-DAR can measure $\delta_{\rm{CP}}$ is shown to be robust even
in the presence of the considered NSIs. Finally, we show that the combination
of $\mu$-DAR along with T2HK can also be used to put mild constraints on the
NSI phase in the vicinity of the maximal CP-violating value for the chosen
benchmark value of $\varepsilon^{\mu e}_{\mu e}=0.01$.
|
[
{
"created": "Tue, 12 Nov 2019 17:31:46 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Mar 2020 09:30:50 GMT",
"version": "v2"
}
] |
2020-03-11
|
[
[
"C.",
"Soumya",
""
],
[
"Ghosh",
"Monojit",
""
],
[
"Raut",
"Sushant K.",
""
],
[
"Sinha",
"Nita",
""
],
[
"Mehta",
"Poonam",
""
]
] |
The muon decay-at-rest ($\mu$-DAR) facility provides us with an ideal platform to probe purely muonic charged-current nonstandard neutrino interactions (NSIs). We propose to probe this class of NSI effects using antineutrinos from a $\mu$-DAR source in conjunction with neutrinos from the future Tokai to Kamioka superbeam experiment with megaton Hyper Kamiokande detector (T2HK). Even though muonic NSIs are absent in neutrino production at T2HK, we show that our proposed hybrid setup comprising $\mu$-DAR and T2HK helps in alleviating the parameter degeneracies that can arise in data. Analytic considerations reveal that the oscillation probability is most sensitive to the NSI parameter in the $\mu$-e sector. For this parameter, we show that the $\mu$-DAR setup can improve on the existing bounds down to around 0.01, especially when the data are combined with neutrino data from T2HK experiment due to the lifting of parameter degeneracies. The high precision with which $\mu$-DAR can measure $\delta_{\rm{CP}}$ is shown to be robust even in the presence of the considered NSIs. Finally, we show that the combination of $\mu$-DAR along with T2HK can also be used to put mild constraints on the NSI phase in the vicinity of the maximal CP-violating value for the chosen benchmark value of $\varepsilon^{\mu e}_{\mu e}=0.01$.
|
hep-ph/0010248
|
Vadim Guzey
|
L. Frankfurt (Tel Aviv U.), V. Guzey (Penn State U. & Adelaide U.), M.
Strikman (Penn State U.)
|
Color coherent phenomena on nuclei and the QCD evolution equation
|
58 pages, 19 figures, Revtex. Minor editor's changes, final version
published in J.Phys. G27 (2001) R23-68
|
J.Phys.G27:R23-146,2001
|
10.1088/0954-3899/27/2/201
|
ADP-00-48/T429
|
hep-ph nucl-th
| null |
We review the phenomenon of color coherence in quantum chromodynamics (QCD),
its implications for hard and soft processes with nuclei, and its experimental
manifestations. The relation of factorization theorems in QCD with color
coherence phenomena in deep inelastic scattering (DIS) and color coherence
phenomena in hard exclusive processes is emphasized. Analyzing numerically the
QCD evolution equation for conventional and skewed parton densities in nuclei,
we study the onset of generalized color transparency and nuclear shadowing of
the sea quark and gluon distributions in nuclei as well as related phenomena.
Such novel results as the dependence of the effective coherence length on $Q^2$
and general trends of the QCD evolution are discussed. The limits of the
applicability of the QCD evolution equation at small Bjorken $x$ are estimated
by comparing the inelastic quark-antiquark- and two gluon-nucleon (nucleus)
cross sections, calculated within the DGLAP approximation, with the dynamical
boundaries, which follow from the unitarity of the $S$ matrix for purely QCD
interactions. We also demonstrate that principles of color coherence play an
important role in the processes of soft diffraction off nuclei.
|
[
{
"created": "Sat, 21 Oct 2000 01:58:53 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Feb 2001 03:42:31 GMT",
"version": "v2"
}
] |
2014-11-17
|
[
[
"Frankfurt",
"L.",
"",
"Tel Aviv U."
],
[
"Guzey",
"V.",
"",
"Penn State U. & Adelaide U."
],
[
"Strikman",
"M.",
"",
"Penn State U."
]
] |
We review the phenomenon of color coherence in quantum chromodynamics (QCD), its implications for hard and soft processes with nuclei, and its experimental manifestations. The relation of factorization theorems in QCD with color coherence phenomena in deep inelastic scattering (DIS) and color coherence phenomena in hard exclusive processes is emphasized. Analyzing numerically the QCD evolution equation for conventional and skewed parton densities in nuclei, we study the onset of generalized color transparency and nuclear shadowing of the sea quark and gluon distributions in nuclei as well as related phenomena. Such novel results as the dependence of the effective coherence length on $Q^2$ and general trends of the QCD evolution are discussed. The limits of the applicability of the QCD evolution equation at small Bjorken $x$ are estimated by comparing the inelastic quark-antiquark- and two gluon-nucleon (nucleus) cross sections, calculated within the DGLAP approximation, with the dynamical boundaries, which follow from the unitarity of the $S$ matrix for purely QCD interactions. We also demonstrate that principles of color coherence play an important role in the processes of soft diffraction off nuclei.
|
hep-ph/0401019
|
Mu-Lin Yan
|
Liu Fang, Li Jin, Yi-Bin Huang and Mu-Lin Yan
|
$\rho-\omega-$Interference in $J/\psi-$Decays and $\rho\to
\pi^+\pi^-\pi^0$ Decay
|
LaTeX file, no figure, to appear in the High Energe Phys and Nuclear
Phys (Beijing)
| null | null | null |
hep-ph
| null |
We study $\rho-\omega-$interference by analyzing $J/\psi\to
\pi^+\pi^-\pi^0\pi^0$. PDG-2002 data on $J/\psi$ decays into $PP$ and $PV$ ($P$
denotes pseudoscalar mesons; $V$, vector mesons) are used to fit a generic
model which describes the $J/\psi$ decays. From the fits, we obtain anomalously
large branching ratio $Br(\rho^0\to \pi^+\pi^-\pi^0)\sim 10^{-3}-10^{-2}$. A
theoretical analysis for it is also provided, and the prediction is in good
agreement with the anomalously large $Br(\rho^0\to \pi^+\pi^-\pi^0)$. By the
fit, we also get the $\eta-\eta'-$mixing angle $\theta=-19.68^o\pm 1.49^o$ and
the constituent quark mass ratio $m_u/m_s\sim 0.6$ which are all reasonable.
|
[
{
"created": "Tue, 6 Jan 2004 08:32:41 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Fang",
"Liu",
""
],
[
"Jin",
"Li",
""
],
[
"Huang",
"Yi-Bin",
""
],
[
"Yan",
"Mu-Lin",
""
]
] |
We study $\rho-\omega-$interference by analyzing $J/\psi\to \pi^+\pi^-\pi^0\pi^0$. PDG-2002 data on $J/\psi$ decays into $PP$ and $PV$ ($P$ denotes pseudoscalar mesons; $V$, vector mesons) are used to fit a generic model which describes the $J/\psi$ decays. From the fits, we obtain anomalously large branching ratio $Br(\rho^0\to \pi^+\pi^-\pi^0)\sim 10^{-3}-10^{-2}$. A theoretical analysis for it is also provided, and the prediction is in good agreement with the anomalously large $Br(\rho^0\to \pi^+\pi^-\pi^0)$. By the fit, we also get the $\eta-\eta'-$mixing angle $\theta=-19.68^o\pm 1.49^o$ and the constituent quark mass ratio $m_u/m_s\sim 0.6$ which are all reasonable.
|
1205.1568
|
Benjamin Farmer
|
Csaba Bal\'azs, Andy Buckley, Daniel Carter, Benjamin Farmer, Martin
White
|
Should we still believe in constrained supersymmetry?
|
38 pages, 14 figures; version as published in EPJC
|
Eur. Phys. J. C (2013) 73:2563
|
10.1140/epjc/s10052-013-2563-y
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We calculate Bayes factors to quantify how the feasibility of the constrained
minimal supersymmetric standard model (CMSSM) has changed in the light of a
series of observations. This is done in the Bayesian spirit where probability
reflects a degree of belief in a proposition and Bayes' theorem tells us how to
update it after acquiring new information. Our experimental baseline is the
approximate knowledge that was available before LEP, and our comparison model
is the Standard Model with a simple dark matter candidate. To quantify the
amount by which experiments have altered our relative belief in the CMSSM since
the baseline data we compute the Bayes factors that arise from learning in
sequence the LEP Higgs constraints, the XENON100 dark matter constraints, the
2011 LHC supersymmetry search results, and the early 2012 LHC Higgs search
results. We find that LEP and the LHC strongly shatter our trust in the CMSSM
(with $M_0$ and $M_{1/2}$ below 2 TeV), reducing its posterior odds by a factor
of approximately two orders of magnitude. This reduction is largely due to
substantial Occam factors induced by the LEP and LHC Higgs searches.
|
[
{
"created": "Tue, 8 May 2012 01:02:33 GMT",
"version": "v1"
},
{
"created": "Sun, 20 May 2012 06:52:11 GMT",
"version": "v2"
},
{
"created": "Mon, 10 Sep 2012 13:41:10 GMT",
"version": "v3"
},
{
"created": "Thu, 28 Nov 2013 05:30:35 GMT",
"version": "v4"
}
] |
2015-06-05
|
[
[
"Balázs",
"Csaba",
""
],
[
"Buckley",
"Andy",
""
],
[
"Carter",
"Daniel",
""
],
[
"Farmer",
"Benjamin",
""
],
[
"White",
"Martin",
""
]
] |
We calculate Bayes factors to quantify how the feasibility of the constrained minimal supersymmetric standard model (CMSSM) has changed in the light of a series of observations. This is done in the Bayesian spirit where probability reflects a degree of belief in a proposition and Bayes' theorem tells us how to update it after acquiring new information. Our experimental baseline is the approximate knowledge that was available before LEP, and our comparison model is the Standard Model with a simple dark matter candidate. To quantify the amount by which experiments have altered our relative belief in the CMSSM since the baseline data we compute the Bayes factors that arise from learning in sequence the LEP Higgs constraints, the XENON100 dark matter constraints, the 2011 LHC supersymmetry search results, and the early 2012 LHC Higgs search results. We find that LEP and the LHC strongly shatter our trust in the CMSSM (with $M_0$ and $M_{1/2}$ below 2 TeV), reducing its posterior odds by a factor of approximately two orders of magnitude. This reduction is largely due to substantial Occam factors induced by the LEP and LHC Higgs searches.
|
2106.14774
|
Bo-Yan Huang
|
Bo-Yan Huang
|
New physics in double Higgs production at NLO
|
28 pages, 24 figures
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
After observing the Higgs boson by the ATLAS and CMS experiments at the LHC,
accurate measurements of its properties, which allow us to study the
electroweak symmetry breaking mechanism, become a high priority for particle
physics. The most promising of extracting the Higgs self-coupling at hadron
colliders is by examining the double Higgs production, especially in the $b
\bar{b} \gamma \gamma$ channel. In this work, we presented full loop
calculation for both SM and New Physics effects of the Higgs pair production to
next-to-leading-order (NLO), including loop-induced processes $gg\to HH$,
$gg\to HHg$, and $qg \to qHH$. We also included the calculation of the
corrections from diagrams with only one QCD coupling in $qg \to qHH$, which was
neglected in the previous studies. With the latest observed limit on the HH
production cross-section, we studied the constraints on the effective Higgs
couplings for the LHC at center-of-mass energies of 14 TeV and a provisional
100 TeV proton collider within the Future-Circular-Collider (FCC) project. To
obtain results better than using total cross-section alone, we focused on the
$b \bar{b} \gamma \gamma$ channel and divided the differential cross-section
into low and high bins based on the total invariant mass and $p_{T}$ spectra.
The new physics effects are further constrained by including extra kinematic
information. However, some degeneracy persists, as shown in previous studies,
especially in determining the Higgs trilinear coupling. Our analysis shows that
the degeneracy is reduced by including the full NLO corrections.
|
[
{
"created": "Mon, 28 Jun 2021 14:47:17 GMT",
"version": "v1"
}
] |
2021-06-29
|
[
[
"Huang",
"Bo-Yan",
""
]
] |
After observing the Higgs boson by the ATLAS and CMS experiments at the LHC, accurate measurements of its properties, which allow us to study the electroweak symmetry breaking mechanism, become a high priority for particle physics. The most promising of extracting the Higgs self-coupling at hadron colliders is by examining the double Higgs production, especially in the $b \bar{b} \gamma \gamma$ channel. In this work, we presented full loop calculation for both SM and New Physics effects of the Higgs pair production to next-to-leading-order (NLO), including loop-induced processes $gg\to HH$, $gg\to HHg$, and $qg \to qHH$. We also included the calculation of the corrections from diagrams with only one QCD coupling in $qg \to qHH$, which was neglected in the previous studies. With the latest observed limit on the HH production cross-section, we studied the constraints on the effective Higgs couplings for the LHC at center-of-mass energies of 14 TeV and a provisional 100 TeV proton collider within the Future-Circular-Collider (FCC) project. To obtain results better than using total cross-section alone, we focused on the $b \bar{b} \gamma \gamma$ channel and divided the differential cross-section into low and high bins based on the total invariant mass and $p_{T}$ spectra. The new physics effects are further constrained by including extra kinematic information. However, some degeneracy persists, as shown in previous studies, especially in determining the Higgs trilinear coupling. Our analysis shows that the degeneracy is reduced by including the full NLO corrections.
|
1301.5516
|
Dmitry Gorbunov
|
S. N. Gninenko, D. S. Gorbunov, and M. E. Shaposhnikov
|
Search for GeV-scale sterile neutrinos responsible for active neutrino
oscillations and baryon asymmetry of the Universe
|
20 pages, Invited Review article for the Special Issue on Neutrino
Physics
| null | null | null |
hep-ph astro-ph.CO hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Standard model of particle physics fails to explain neutrino oscillations,
dark matter and baryon asymmetry of the Universe. All these problems can be
solved with three sterile neutrinos added to the model. Quite remarkably, if
sterile neutrino masses are well below the electroweak scale, this modification
--- Neutrino Minimal Standard Model (nuMSM) --- can be tested experimentally.
We discuss a new experiment on search for decays of GeV-scale sterile
neutrinos, which in the framework of the nuMSM are responsible for the
matter-antimatter asymmetry generation and for the active neutrino masses. If
lighter than 2 GeV, these particles can be produced in decays of charm mesons
generated by high energy protons in a target of a proton beam-dump experiment,
and subsequently decay into light SM particles. In order to fully explore this
sector of the nuMSM, the new experiment requires data obtained with at least
10^{20} incident protons on target (achievable at CERN SPS in the future), and
a big volume detector constructed from a large amount of identical single
modules, with a total sterile neutrino decay length of few kilometers. The
preliminary feasibility study for the proposed experiment shows that it has
sensitivity which may either lead to the discovery of new particles below the
Fermi scale --- right-handed partners of neutrinos --- or rule out see-saw
sterile neutrinos with masses below 2 GeV.
|
[
{
"created": "Wed, 23 Jan 2013 14:39:24 GMT",
"version": "v1"
}
] |
2013-01-24
|
[
[
"Gninenko",
"S. N.",
""
],
[
"Gorbunov",
"D. S.",
""
],
[
"Shaposhnikov",
"M. E.",
""
]
] |
Standard model of particle physics fails to explain neutrino oscillations, dark matter and baryon asymmetry of the Universe. All these problems can be solved with three sterile neutrinos added to the model. Quite remarkably, if sterile neutrino masses are well below the electroweak scale, this modification --- Neutrino Minimal Standard Model (nuMSM) --- can be tested experimentally. We discuss a new experiment on search for decays of GeV-scale sterile neutrinos, which in the framework of the nuMSM are responsible for the matter-antimatter asymmetry generation and for the active neutrino masses. If lighter than 2 GeV, these particles can be produced in decays of charm mesons generated by high energy protons in a target of a proton beam-dump experiment, and subsequently decay into light SM particles. In order to fully explore this sector of the nuMSM, the new experiment requires data obtained with at least 10^{20} incident protons on target (achievable at CERN SPS in the future), and a big volume detector constructed from a large amount of identical single modules, with a total sterile neutrino decay length of few kilometers. The preliminary feasibility study for the proposed experiment shows that it has sensitivity which may either lead to the discovery of new particles below the Fermi scale --- right-handed partners of neutrinos --- or rule out see-saw sterile neutrinos with masses below 2 GeV.
|
hep-ph/9807324
|
Roland Kirschner
|
D. Yu. Ivanov and R. Kirschner
|
Polarization in diffractive electroproduction of light vector mesons
|
23 pages LATEX, 2 EPS figures included
|
Phys.Rev. D58 (1998) 114026
|
10.1103/PhysRevD.58.114026
|
NTZ 20/98
|
hep-ph
| null |
We study in perturbative QCD the helicity ampltiudes of the process
$\gamma^{*} p \to \rho p $ at large virtualities $Q$ of the photon
$\gamma^{*}$. We estimate all spin flip amplitudes taking into account an
important effect of the scale behaviour of the gluon density. The transition of
a transverse virtual photon to a longitudinal vector meson is not small at
typical HERA conditions. This helicity non-conserving amplitude leads by
interference to a measurable effect in the distribution of the angle between
the electron scattering and the meson production planes.
|
[
{
"created": "Fri, 10 Jul 1998 06:52:00 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Ivanov",
"D. Yu.",
""
],
[
"Kirschner",
"R.",
""
]
] |
We study in perturbative QCD the helicity ampltiudes of the process $\gamma^{*} p \to \rho p $ at large virtualities $Q$ of the photon $\gamma^{*}$. We estimate all spin flip amplitudes taking into account an important effect of the scale behaviour of the gluon density. The transition of a transverse virtual photon to a longitudinal vector meson is not small at typical HERA conditions. This helicity non-conserving amplitude leads by interference to a measurable effect in the distribution of the angle between the electron scattering and the meson production planes.
|
2010.07335
|
Andrew Blance
|
Andrew Blance and Michael Spannowsky
|
Quantum Machine Learning for Particle Physics using a Variational
Quantum Classifier
|
20 pages, 6 figures
| null |
10.1007/JHEP02(2021)212
|
IPPP/20/48
|
hep-ph hep-ex quant-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Quantum machine learning aims to release the prowess of quantum computing to
improve machine learning methods. By combining quantum computing methods with
classical neural network techniques we aim to foster an increase of performance
in solving classification problems. Our algorithm is designed for existing and
near-term quantum devices. We propose a novel hybrid variational quantum
classifier that combines the quantum gradient descent method with steepest
gradient descent to optimise the parameters of the network. By applying this
algorithm to a resonance search in di-top final states, we find that this
method has a better learning outcome than a classical neural network or a
quantum machine learning method trained with a non-quantum optimisation method.
The classifiers ability to be trained on small amounts of data indicates its
benefits in data-driven classification problems.
|
[
{
"created": "Wed, 14 Oct 2020 18:05:49 GMT",
"version": "v1"
}
] |
2021-03-17
|
[
[
"Blance",
"Andrew",
""
],
[
"Spannowsky",
"Michael",
""
]
] |
Quantum machine learning aims to release the prowess of quantum computing to improve machine learning methods. By combining quantum computing methods with classical neural network techniques we aim to foster an increase of performance in solving classification problems. Our algorithm is designed for existing and near-term quantum devices. We propose a novel hybrid variational quantum classifier that combines the quantum gradient descent method with steepest gradient descent to optimise the parameters of the network. By applying this algorithm to a resonance search in di-top final states, we find that this method has a better learning outcome than a classical neural network or a quantum machine learning method trained with a non-quantum optimisation method. The classifiers ability to be trained on small amounts of data indicates its benefits in data-driven classification problems.
|
1707.09749
|
Bartosz Fornal
|
Bartosz Fornal
|
Is There a Sign of New Physics in Beryllium Transitions?
|
19 pages + references, 10 figures; Invited talk given at the American
Physical Society April Meeting 2017, Washington, DC, January 28, 2017; based
mainly on arXiv:1604.07411 [hep-ph] and arXiv:1608.03591 [hep-ph]
|
Int. J. Mod. Phys. A 32 (2017) 1730020
|
10.1142/S0217751X17300204
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss the current status of the anomaly in beryllium-8 nuclear
transitions recently reported in the angular distribution of internal
conversion electron-positron pairs. We present a phenomenological analysis of
the signal and review the models proposed to explain it, focusing on those
involving a new light protophobic vector gauge boson. We also elaborate on the
prospects of verifying the anomaly in present and future experiments.
|
[
{
"created": "Mon, 31 Jul 2017 08:02:35 GMT",
"version": "v1"
}
] |
2017-08-28
|
[
[
"Fornal",
"Bartosz",
""
]
] |
We discuss the current status of the anomaly in beryllium-8 nuclear transitions recently reported in the angular distribution of internal conversion electron-positron pairs. We present a phenomenological analysis of the signal and review the models proposed to explain it, focusing on those involving a new light protophobic vector gauge boson. We also elaborate on the prospects of verifying the anomaly in present and future experiments.
|
2310.09962
|
Bennie F. L. Ward
|
B.F.L. Ward (1), S. Jadach (2), W. Placzek (3), M. Skrzypek (2), Z.A.
Was (2), S.A. Yost (4) ((1) Department of Physics, Baylor University, Waco,
TX, USA, (2) Institute Of Nuclear Physics, Polish Academy of Sciences,
Krakow, PL, (3) Institute of Applied Computer Science, Jagiellonian
University, Krakow, PL, (4) Department of Physics, The Citadel, Charleston,
SC, USA)
|
New Results from IR-Improved Amplitude-Based Resummation in Quantum
Field Theory
|
9 pages, 5 figures, presented by BFLW at RADCOR2023, Crieff,
Scotland, UK
| null | null |
BU-HEPP-23-02
|
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
There is a continuing effort to support and prepare the precision physics
programs for the present and planned future colliders such as HL-LHC, FCC,
CLIC, CEPC, and CPPC. We discuss new results from IR-improved amplitude-based
resummation in quantum field theory relevant to such support and preparation
with some emphasis on the interplay between soft and collinear resummation
algebras.
|
[
{
"created": "Sun, 15 Oct 2023 21:45:43 GMT",
"version": "v1"
}
] |
2023-10-17
|
[
[
"Ward",
"B. F. L.",
""
],
[
"Jadach",
"S.",
""
],
[
"Placzek",
"W.",
""
],
[
"Skrzypek",
"M.",
""
],
[
"Was",
"Z. A.",
""
],
[
"Yost",
"S. A.",
""
]
] |
There is a continuing effort to support and prepare the precision physics programs for the present and planned future colliders such as HL-LHC, FCC, CLIC, CEPC, and CPPC. We discuss new results from IR-improved amplitude-based resummation in quantum field theory relevant to such support and preparation with some emphasis on the interplay between soft and collinear resummation algebras.
|
hep-ph/0008089
|
Jen-Chieh Peng
|
J. C. Peng
|
Flavor Asymmetry of the Nucleon Sea
|
9 pages, 3 figures. Invited paper presented at the "16th
International Conference on Few-Body Problem in Physics" March 2000
|
Nucl.Phys. A684 (2001) 80-88
|
10.1016/S0375-9474(01)00491-2
| null |
hep-ph
| null |
Recent deep inelastic scattering and Drell-Yan experiments have revealed a
surprisingly large asymmetry between the up and down sea quark distributions in
the nucleon. The current status of the flavor asymmetry of the nucleon sea is
reviewed. Implications of various theoretical models and possible future
measurements are also discussed.
|
[
{
"created": "Wed, 9 Aug 2000 20:34:15 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Peng",
"J. C.",
""
]
] |
Recent deep inelastic scattering and Drell-Yan experiments have revealed a surprisingly large asymmetry between the up and down sea quark distributions in the nucleon. The current status of the flavor asymmetry of the nucleon sea is reviewed. Implications of various theoretical models and possible future measurements are also discussed.
|
1205.2303
|
Ye-Ling Zhou
|
Ye-Ling Zhou
|
Neutrino masses and flavor mixing in a generalized inverse seesaw model
with a universal two-zero texture
|
22 pages, 4 figures, more discussions and references added, accepted
for publication in Phys. Rev. D
| null |
10.1103/PhysRevD.86.093011
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A generalized inverse seesaw model, in which the 9x9 neutrino mass matrix has
vanishing (1,1) and (1,3) submatrices, is proposed. This is similar to the
universal two-zero texture which gives vanishing (1,1) and (1,3) elements of
the 3x3 mass matrices in both the charged lepton and neutrino sectors. We
consider the Z_6 x Z_6 group to realize such texture zeros. We study this
generalized inverse seesaw model systematically and derive the seesaw formula
for the 3x3 mass matrix of three active neutrinos. We also analyze the
universal two-zero texture in the general case and propose two ansatze to
reduce the number of free parameters. Taking account of the new result of
\theta_{13} from the Daya Bay experiment, we constrain the parameter space of
the universal two-zero texture in the general case and in the two ansatze,
respectively. We find that one of the ansatze works well.
|
[
{
"created": "Thu, 10 May 2012 16:30:34 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Oct 2012 14:48:32 GMT",
"version": "v2"
}
] |
2015-06-05
|
[
[
"Zhou",
"Ye-Ling",
""
]
] |
A generalized inverse seesaw model, in which the 9x9 neutrino mass matrix has vanishing (1,1) and (1,3) submatrices, is proposed. This is similar to the universal two-zero texture which gives vanishing (1,1) and (1,3) elements of the 3x3 mass matrices in both the charged lepton and neutrino sectors. We consider the Z_6 x Z_6 group to realize such texture zeros. We study this generalized inverse seesaw model systematically and derive the seesaw formula for the 3x3 mass matrix of three active neutrinos. We also analyze the universal two-zero texture in the general case and propose two ansatze to reduce the number of free parameters. Taking account of the new result of \theta_{13} from the Daya Bay experiment, we constrain the parameter space of the universal two-zero texture in the general case and in the two ansatze, respectively. We find that one of the ansatze works well.
|
1910.13699
|
Luigi Delle Rose
|
Stefania De Curtis, Luigi Delle Rose, Stefano Moretti, Key Yagyu
|
A Composite 2-Higgs Doublet Model
|
7 pages, 6 figures, prepared for the proceedings of EPS-HEP2019 -
10-17 July, 2019, Ghent, Belgium
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In the context of Composite Higgs Models we consider the realisation of an
extended Higgs sector with two Higgs doublets arising as pseudo Nambu-Goldstone
bosons from a $\textrm{SO}(6) \to \textrm{SO}(4) \times \textrm{SO}(2)$
breaking. The properties of the Higgses are obtained in terms of the
fundamental parameters of the composite sector, such as masses, Yukawa and
gauge couplings of the new spin-1/2 and spin-1 resonances. After computing the
Higgs potential from the explicit breaking of the $\textrm{SO}(6)$ global
symmetry by the partial compositeness of fermions and gauge bosons, the main
focus is to derive the phenomenological properties of the Higgs bosons and to
highlight the main signatures of the Composite 2-Higgs Doublet Model at the
Large Hadron Collider, including modifications to the SM-like Higgs couplings,
production and decay channels of heavier Higgs states.
|
[
{
"created": "Wed, 30 Oct 2019 07:24:45 GMT",
"version": "v1"
}
] |
2019-10-31
|
[
[
"De Curtis",
"Stefania",
""
],
[
"Rose",
"Luigi Delle",
""
],
[
"Moretti",
"Stefano",
""
],
[
"Yagyu",
"Key",
""
]
] |
In the context of Composite Higgs Models we consider the realisation of an extended Higgs sector with two Higgs doublets arising as pseudo Nambu-Goldstone bosons from a $\textrm{SO}(6) \to \textrm{SO}(4) \times \textrm{SO}(2)$ breaking. The properties of the Higgses are obtained in terms of the fundamental parameters of the composite sector, such as masses, Yukawa and gauge couplings of the new spin-1/2 and spin-1 resonances. After computing the Higgs potential from the explicit breaking of the $\textrm{SO}(6)$ global symmetry by the partial compositeness of fermions and gauge bosons, the main focus is to derive the phenomenological properties of the Higgs bosons and to highlight the main signatures of the Composite 2-Higgs Doublet Model at the Large Hadron Collider, including modifications to the SM-like Higgs couplings, production and decay channels of heavier Higgs states.
|
1102.3361
|
Emidio Gabrielli
|
Emidio Gabrielli and Barbara Mele
|
Effective Yukawa couplings and flavor-changing Higgs boson decays at
linear colliders
|
23 pages, 7 figures, 5 tables
|
Phys.Rev.D83:073009,2011
|
10.1103/PhysRevD.83.073009
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We analyze the advantages of a linear-collider program for testing a recent
theoretical proposal where the Higgs-boson Yukawa couplings are radiatively
generated, keeping unchanged the standard-model mechanism for
electroweak-gauge-symmetry breaking. Fermion masses arise at a large energy
scale through an unknown mechanism, and the standard model at the electroweak
scale is regarded as an effective field theory. In this scenario, Higgs boson
decays into photons and electroweak gauge-boson pairs are considerably enhanced
for a light Higgs boson, which makes a signal observation at the LHC
straightforward. On the other hand, the clean environment of a linear collider
is required to directly probe the radiative fermionic sector of the Higgs boson
couplings. Also, we show that the flavor-changing Higgs-boson decays are
dramatically enhanced with respect to the standard model. In particular, we
find a measurable branching ratio in the range (10^{-4}-10^{-3}) for the decay
H\to bs for a Higgs boson lighter than 140 GeV, depending on the high-energy
scale where Yukawa couplings vanish. We present a detailed analysis of the
Higgs boson production cross sections at linear colliders for interesting decay
signatures, as well as branching-ratio correlations for different
flavor-conserving/nonconserving fermionic decays.
|
[
{
"created": "Wed, 16 Feb 2011 16:05:37 GMT",
"version": "v1"
}
] |
2011-05-12
|
[
[
"Gabrielli",
"Emidio",
""
],
[
"Mele",
"Barbara",
""
]
] |
We analyze the advantages of a linear-collider program for testing a recent theoretical proposal where the Higgs-boson Yukawa couplings are radiatively generated, keeping unchanged the standard-model mechanism for electroweak-gauge-symmetry breaking. Fermion masses arise at a large energy scale through an unknown mechanism, and the standard model at the electroweak scale is regarded as an effective field theory. In this scenario, Higgs boson decays into photons and electroweak gauge-boson pairs are considerably enhanced for a light Higgs boson, which makes a signal observation at the LHC straightforward. On the other hand, the clean environment of a linear collider is required to directly probe the radiative fermionic sector of the Higgs boson couplings. Also, we show that the flavor-changing Higgs-boson decays are dramatically enhanced with respect to the standard model. In particular, we find a measurable branching ratio in the range (10^{-4}-10^{-3}) for the decay H\to bs for a Higgs boson lighter than 140 GeV, depending on the high-energy scale where Yukawa couplings vanish. We present a detailed analysis of the Higgs boson production cross sections at linear colliders for interesting decay signatures, as well as branching-ratio correlations for different flavor-conserving/nonconserving fermionic decays.
|
1305.4320
|
S. V. Troitsky
|
J.-M. Frere, M. Libanov, S. Mollet and S. Troitsky
|
Neutrino hierarchy and fermion spectrum from a single family in six
dimensions: realistic predictions
|
18 pages, 1 figure. v2: minor clarifications. Version accepted by
JHEP
|
JHEP 08(2013)078
|
10.1007/JHEP08(2013)078
|
INR-TH-2013-27
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this paper, we move from a "proof of concept" to challenging predictions
in a flavour model emerging from a single fermion family in six dimensions
(6-D) with the two extra dimensions compactified on a sphere. The most striking
predictions (beyond the basic ingredients already demonstrated for a realistic
quark mass pattern) are for the neutrino sector. Not only can 4-D Majorana
masses be generated from 6-D (where no Majorana spinors exist), but Majorana
masses are naturally associated to large mixing. The model favours inverted
hierarchy and a quasi-Dirac partial suppression of neutrinoless double beta
decay.
|
[
{
"created": "Sun, 19 May 2013 03:41:35 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Jul 2013 11:02:54 GMT",
"version": "v2"
}
] |
2013-08-21
|
[
[
"Frere",
"J. -M.",
""
],
[
"Libanov",
"M.",
""
],
[
"Mollet",
"S.",
""
],
[
"Troitsky",
"S.",
""
]
] |
In this paper, we move from a "proof of concept" to challenging predictions in a flavour model emerging from a single fermion family in six dimensions (6-D) with the two extra dimensions compactified on a sphere. The most striking predictions (beyond the basic ingredients already demonstrated for a realistic quark mass pattern) are for the neutrino sector. Not only can 4-D Majorana masses be generated from 6-D (where no Majorana spinors exist), but Majorana masses are naturally associated to large mixing. The model favours inverted hierarchy and a quasi-Dirac partial suppression of neutrinoless double beta decay.
|
1705.06919
|
Simon Platzer
|
Johannes Bellm, Stefan Gieseke, David Grellscheid, Patrick
Kirchgae{\ss}er, Frash\"er Loshaj, Graeme Nail, Andreas Papaefstathiou, Simon
Pl\"atzer, Radek Podskubka, Michael Rauch, Christian Reuschle, Peter
Richardson, Peter Schichtel, Michael H. Seymour, Andrzej Si\'odmok, Stephen
Webster
|
Herwig 7.1 Release Note
|
7 pages, 7 figures. Herwig is available from
https://herwig.hepforge.org/
| null | null |
CERN-PH-TH-2017-109, MAN/HEP/2017/08, UWTHPH-2017-10,
IFJPAN-IV-2017-7, NIKHEF 2017-026, HERWIG-2017-02, KA-TP-19-2017,
MCnet-17-08, IPPP/17/40
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A new release of the Monte Carlo event generator Herwig (version 7.1) is now
available. This version introduces a number of improvements, notably: multi-jet
merging with the dipole shower at LO and NLO QCD; a new model for soft
interactions and diffraction; improvements to mass effects and top decays in
the dipole shower, as well as a new tune of the hadronisation parameters.
|
[
{
"created": "Fri, 19 May 2017 10:29:00 GMT",
"version": "v1"
}
] |
2017-05-22
|
[
[
"Bellm",
"Johannes",
""
],
[
"Gieseke",
"Stefan",
""
],
[
"Grellscheid",
"David",
""
],
[
"Kirchgaeßer",
"Patrick",
""
],
[
"Loshaj",
"Frashër",
""
],
[
"Nail",
"Graeme",
""
],
[
"Papaefstathiou",
"Andreas",
""
],
[
"Plätzer",
"Simon",
""
],
[
"Podskubka",
"Radek",
""
],
[
"Rauch",
"Michael",
""
],
[
"Reuschle",
"Christian",
""
],
[
"Richardson",
"Peter",
""
],
[
"Schichtel",
"Peter",
""
],
[
"Seymour",
"Michael H.",
""
],
[
"Siódmok",
"Andrzej",
""
],
[
"Webster",
"Stephen",
""
]
] |
A new release of the Monte Carlo event generator Herwig (version 7.1) is now available. This version introduces a number of improvements, notably: multi-jet merging with the dipole shower at LO and NLO QCD; a new model for soft interactions and diffraction; improvements to mass effects and top decays in the dipole shower, as well as a new tune of the hadronisation parameters.
|
hep-ph/9906501
|
Shinji Tsujikawa
|
S. Tsujikawa, K. Maeda (Waseda University), T. Torii (Tokyo Institute
of Technology)
|
Preheating with non-minimally coupled scalar fields in higher-curvature
inflation models
|
31pages, 12figures
|
Phys.Rev.D60:123505,1999
|
10.1103/PhysRevD.60.123505
| null |
hep-ph astro-ph gr-qc hep-th
| null |
In higher-curvature inflation models ($R+\alpha_n R^n$), we study a
parametric preheating of a scalar field $\chi$ coupled non-minimally to a
spacetime curvature $R$ ($\xi R \chi^2$). In the case of $R^2$-inflation model,
efficient preheating becomes possible for rather small values of $\xi$, i.e.
$|\xi|< several. Although the maximal fluctuation $\sqrt{< \chi^2 >}_{max}
\approx 2 \times10^{17}$ GeV for $\xi \approx -4$ is almost the same as the
chaotic inflation model with a non-minimally coupled $\chi$ field, the growth
rate of the fluctuation becomes much larger and efficient preheating is
realized. We also investigate preheating for $R^4$ model and find that the
maximal fluctuation is $\sqrt{< \chi^2 >}_{max} \approx 8 \times 10^{16}$ GeV
for $\xi \approx -35$.
|
[
{
"created": "Fri, 25 Jun 1999 12:30:40 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Jun 1999 07:49:23 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Tsujikawa",
"S.",
"",
"Waseda University"
],
[
"Maeda",
"K.",
"",
"Waseda University"
],
[
"Torii",
"T.",
"",
"Tokyo Institute\n of Technology"
]
] |
In higher-curvature inflation models ($R+\alpha_n R^n$), we study a parametric preheating of a scalar field $\chi$ coupled non-minimally to a spacetime curvature $R$ ($\xi R \chi^2$). In the case of $R^2$-inflation model, efficient preheating becomes possible for rather small values of $\xi$, i.e. $|\xi|< several. Although the maximal fluctuation $\sqrt{< \chi^2 >}_{max} \approx 2 \times10^{17}$ GeV for $\xi \approx -4$ is almost the same as the chaotic inflation model with a non-minimally coupled $\chi$ field, the growth rate of the fluctuation becomes much larger and efficient preheating is realized. We also investigate preheating for $R^4$ model and find that the maximal fluctuation is $\sqrt{< \chi^2 >}_{max} \approx 8 \times 10^{16}$ GeV for $\xi \approx -35$.
|
2403.16106
|
Sergey Ostapchenko
|
Sergey Ostapchenko
|
QGSJET-III model of high energy hadronic interactions: II. Particle
production and extensive air shower characteristics
|
Version 2: accepted for PRD
| null | null | null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
The hadronization procedure of the QGSJET-III Monte Carlo (MC) generator of
high energy hadronic interactions is discussed. Selected results of the model,
regarding production spectra of secondary particles, are presented in
comparison to experimental data and to the corresponding predictions of the
QGSJET-II-04 MC generator. The model is applied to calculations of basic
characteristics of extensive air showers initiated by cosmic ray interactions
in the atmosphere and the results are compared to predictions of other MC
generators of cosmic ray interactions.
|
[
{
"created": "Sun, 24 Mar 2024 11:50:23 GMT",
"version": "v1"
},
{
"created": "Sat, 27 Apr 2024 20:07:20 GMT",
"version": "v2"
}
] |
2024-04-30
|
[
[
"Ostapchenko",
"Sergey",
""
]
] |
The hadronization procedure of the QGSJET-III Monte Carlo (MC) generator of high energy hadronic interactions is discussed. Selected results of the model, regarding production spectra of secondary particles, are presented in comparison to experimental data and to the corresponding predictions of the QGSJET-II-04 MC generator. The model is applied to calculations of basic characteristics of extensive air showers initiated by cosmic ray interactions in the atmosphere and the results are compared to predictions of other MC generators of cosmic ray interactions.
|
1710.10868
|
Mariola Klusek-Gawenda
|
Antoni Szczurek and Mariola Klusek-Gawenda
|
$\gamma\gamma \to \gamma \gamma$ scattering in ultrarelativistic UPC
|
5 pages, 3 figures, talk was given by Antoni Szczurek at European
Physical Society conference on High Energy Physics (EPS-HEP 2017), Venice,
Italy. Two references were added. arXiv admin note: text overlap with
arXiv:1610.08546, arXiv:1611.05601, arXiv:1606.09038
| null | null | null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss diphoton semi(exclusive) production in ultraperipheral lead-lead
collisions at energy of $\sqrt{s_{NN}}$ = 5.5 TeV (LHC) and in proton-proton
collisions at $\sqrt{s_{pp}}$ = 7 TeV (LHC) and $\sqrt{s_{pp}}$ = 100 TeV
(FCC). The nuclear calculations are based on equivalent photon approximation in
the impact parameter space. The cross sections for elementary $\gamma\gamma \to
\gamma\gamma$ subprocess are calculated including three different mechanisms:
box diagrams with leptons and quarks in the loops, a VDM-Regge contribution
with virtual intermediate hadronic excitations of the photons and the two-gluon
exchange contribution. We get relatively high cross sections in heavy ion
collisions. This opens a possibility to study the light-by-light (quasi)elastic
scattering at the LHC. We find that the cross section for elastic
$\gamma\gamma$ scattering could be measured in the lead-lead collisions for the
diphoton invariant mass up to $W_{\gamma\gamma} \approx$ 15 - 20 GeV. Our
Standard Model predictions are compared to a recent ATLAS experimental result.
We present differential distributions for PbPb$\to$PbPb$\gamma\gamma$ and
pp$\to$pp$\gamma\gamma$ reaction.
|
[
{
"created": "Mon, 30 Oct 2017 11:08:44 GMT",
"version": "v1"
},
{
"created": "Fri, 3 Nov 2017 11:59:15 GMT",
"version": "v2"
},
{
"created": "Tue, 14 Nov 2017 08:47:42 GMT",
"version": "v3"
}
] |
2017-11-16
|
[
[
"Szczurek",
"Antoni",
""
],
[
"Klusek-Gawenda",
"Mariola",
""
]
] |
We discuss diphoton semi(exclusive) production in ultraperipheral lead-lead collisions at energy of $\sqrt{s_{NN}}$ = 5.5 TeV (LHC) and in proton-proton collisions at $\sqrt{s_{pp}}$ = 7 TeV (LHC) and $\sqrt{s_{pp}}$ = 100 TeV (FCC). The nuclear calculations are based on equivalent photon approximation in the impact parameter space. The cross sections for elementary $\gamma\gamma \to \gamma\gamma$ subprocess are calculated including three different mechanisms: box diagrams with leptons and quarks in the loops, a VDM-Regge contribution with virtual intermediate hadronic excitations of the photons and the two-gluon exchange contribution. We get relatively high cross sections in heavy ion collisions. This opens a possibility to study the light-by-light (quasi)elastic scattering at the LHC. We find that the cross section for elastic $\gamma\gamma$ scattering could be measured in the lead-lead collisions for the diphoton invariant mass up to $W_{\gamma\gamma} \approx$ 15 - 20 GeV. Our Standard Model predictions are compared to a recent ATLAS experimental result. We present differential distributions for PbPb$\to$PbPb$\gamma\gamma$ and pp$\to$pp$\gamma\gamma$ reaction.
|
1803.08044
|
Nirmal Raj
|
Joseph Bramante, Benjamin Broerman, Rafael F. Lang, Nirmal Raj
|
Saturated Overburden Scattering and the Multiscatter Frontier:
Discovering Dark Matter at the Planck Mass and Beyond
|
6 pages + references, 3 figures
|
Phys. Rev. D 98, 083516 (2018)
|
10.1103/PhysRevD.98.083516
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We show that underground experiments like LUX/LZ, PandaX-II, XENON, and PICO
could discover dark matter up to the Planck mass and beyond, with new searches
for dark matter that scatters multiple times in these detectors. This opens up
significant discovery potential via re-analysis of existing and future data. We
also identify a new effect which substantially enhances experimental
sensitivity to large dark matter scattering cross-sections: while passing
through atmospheric or solid overburden, there is a maximum number of scatters
that dark matter undergoes, determined by the total number of scattering sites
it passes, such as nuclei and electrons. This extends the reach of some
published limits and future analyses to arbitrarily large dark matter
scattering cross-sections.
|
[
{
"created": "Wed, 21 Mar 2018 18:00:01 GMT",
"version": "v1"
}
] |
2018-10-17
|
[
[
"Bramante",
"Joseph",
""
],
[
"Broerman",
"Benjamin",
""
],
[
"Lang",
"Rafael F.",
""
],
[
"Raj",
"Nirmal",
""
]
] |
We show that underground experiments like LUX/LZ, PandaX-II, XENON, and PICO could discover dark matter up to the Planck mass and beyond, with new searches for dark matter that scatters multiple times in these detectors. This opens up significant discovery potential via re-analysis of existing and future data. We also identify a new effect which substantially enhances experimental sensitivity to large dark matter scattering cross-sections: while passing through atmospheric or solid overburden, there is a maximum number of scatters that dark matter undergoes, determined by the total number of scattering sites it passes, such as nuclei and electrons. This extends the reach of some published limits and future analyses to arbitrarily large dark matter scattering cross-sections.
|
1701.07665
|
Yohei Ema
|
Yohei Ema
|
Higgs Scalaron Mixed Inflation
|
10 pages, 4 figures; v2: references added, typos corrected,
terminology changed; v3: appendices added, version accepted in PLB
| null |
10.1016/j.physletb.2017.04.060
|
UT 17-04
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss the inflationary dynamics of a system with a non-minimal coupling
between the Higgs and the Ricci scalar as well as a Ricci scalar squared term.
There are two scalar modes in this system, i.e. the Higgs and the spin-zero
mode of the graviton, or the scalaron. We study the two-field dynamics of the
Higgs and the scalaron during inflation, and clarify the condition where
inflation is dominated by the Higgs/scalaron. We also find that the cut-off
scale at around the vacuum is as large as the Planck scale, and hence there is
no unitarity issue, although there is a constraint on the couplings from the
perturbativity of the theory at around the vacuum.
|
[
{
"created": "Thu, 26 Jan 2017 11:54:52 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Feb 2017 07:12:45 GMT",
"version": "v2"
},
{
"created": "Tue, 25 Apr 2017 08:29:17 GMT",
"version": "v3"
}
] |
2017-05-03
|
[
[
"Ema",
"Yohei",
""
]
] |
We discuss the inflationary dynamics of a system with a non-minimal coupling between the Higgs and the Ricci scalar as well as a Ricci scalar squared term. There are two scalar modes in this system, i.e. the Higgs and the spin-zero mode of the graviton, or the scalaron. We study the two-field dynamics of the Higgs and the scalaron during inflation, and clarify the condition where inflation is dominated by the Higgs/scalaron. We also find that the cut-off scale at around the vacuum is as large as the Planck scale, and hence there is no unitarity issue, although there is a constraint on the couplings from the perturbativity of the theory at around the vacuum.
|
2104.14382
|
Fei Sun
|
Fei Sun, Anping Huang
|
The properties of strange quark matter under strong rotation
|
20 pages, 16 figures
| null | null | null |
hep-ph hep-th
|
http://creativecommons.org/licenses/by/4.0/
|
We investigate the rotating quark matter in the three-flavor Nambu and
Jona-Lasinio (NJL) model. The chiral condensation, spin polarization and number
susceptibility of the light and strange quarks are carefully studied at finite
temperature without or with finite chemical potential in this model. We find
that the rotation suppresses the chiral condensation and enhances the
first-order quark spin polarization, however for the second-order quark spin
polarization and quark number susceptibility the effect is complicated and
interesting. When extending to the situation with finite chemical potential, we
find the angular velocity also plays a crucial role, at small angular velocity
the chemical potential enhances the susceptibility, however in the middle
region of angular velocity the effect of the chemical potential is suppressed
by the angular velocity and susceptibility can be changed considerably, it can
be observed that at very low temperature in the presence of quark chemical
potential the quark number susceptibility has two maxima with increasing
angular velocity. Furthermore, it is found that at sufficiently large angular
velocity the contributions played by light quark and strange quark to these
phenomena are almost equal. we also explored the phase diagram in the
$T$-$\omega$ plane, we observe that there exist first order phase transitions
for the rotating system and the first order phase transition lines move toward
a higher temperature for decreasing angular velocity. It is also found that the
different chemical potentials change the boundary of phase diagram, and that a
larger chemical potential shifts down the critical temperature. We expect these
studies to be used to understand the chiral symmetry breaking and restoration
as well as probe the QCD phase transition.
|
[
{
"created": "Thu, 29 Apr 2021 14:47:25 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Jun 2021 08:46:40 GMT",
"version": "v2"
},
{
"created": "Tue, 23 Nov 2021 03:50:14 GMT",
"version": "v3"
}
] |
2021-11-24
|
[
[
"Sun",
"Fei",
""
],
[
"Huang",
"Anping",
""
]
] |
We investigate the rotating quark matter in the three-flavor Nambu and Jona-Lasinio (NJL) model. The chiral condensation, spin polarization and number susceptibility of the light and strange quarks are carefully studied at finite temperature without or with finite chemical potential in this model. We find that the rotation suppresses the chiral condensation and enhances the first-order quark spin polarization, however for the second-order quark spin polarization and quark number susceptibility the effect is complicated and interesting. When extending to the situation with finite chemical potential, we find the angular velocity also plays a crucial role, at small angular velocity the chemical potential enhances the susceptibility, however in the middle region of angular velocity the effect of the chemical potential is suppressed by the angular velocity and susceptibility can be changed considerably, it can be observed that at very low temperature in the presence of quark chemical potential the quark number susceptibility has two maxima with increasing angular velocity. Furthermore, it is found that at sufficiently large angular velocity the contributions played by light quark and strange quark to these phenomena are almost equal. we also explored the phase diagram in the $T$-$\omega$ plane, we observe that there exist first order phase transitions for the rotating system and the first order phase transition lines move toward a higher temperature for decreasing angular velocity. It is also found that the different chemical potentials change the boundary of phase diagram, and that a larger chemical potential shifts down the critical temperature. We expect these studies to be used to understand the chiral symmetry breaking and restoration as well as probe the QCD phase transition.
|
hep-ph/0305134
|
Shinta Kasuya
|
S. Kasuya, M. Kawasaki, and Fuminobu Takahashi
|
MSSM curvaton in the gauge-mediated SUSY breaking
|
12 pages
|
Phys.Lett. B578 (2004) 259-268
|
10.1016/j.physletb.2003.10.079
| null |
hep-ph
| null |
We study the curvaton scenario using the MSSM flat directions in the
gauge-mediated SUSY breaking model. We find that the fluctuations in the both
radial and phase directions can be responsible for the density perturbations in
the universe through the curvaton mechanism. Although it has been considered
difficult to have a successful curvaton scenario with the use of those flat
directions, it is overcome by taking account of the finite temperature effects,
which induce a negative thermal logarithmic term in the effective potential of
the flat direction.
|
[
{
"created": "Tue, 13 May 2003 08:55:27 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Jul 2003 10:48:54 GMT",
"version": "v2"
},
{
"created": "Fri, 17 Oct 2003 05:00:38 GMT",
"version": "v3"
},
{
"created": "Mon, 20 Oct 2003 06:05:15 GMT",
"version": "v4"
},
{
"created": "Tue, 21 Oct 2003 05:23:27 GMT",
"version": "v5"
}
] |
2010-04-05
|
[
[
"Kasuya",
"S.",
""
],
[
"Kawasaki",
"M.",
""
],
[
"Takahashi",
"Fuminobu",
""
]
] |
We study the curvaton scenario using the MSSM flat directions in the gauge-mediated SUSY breaking model. We find that the fluctuations in the both radial and phase directions can be responsible for the density perturbations in the universe through the curvaton mechanism. Although it has been considered difficult to have a successful curvaton scenario with the use of those flat directions, it is overcome by taking account of the finite temperature effects, which induce a negative thermal logarithmic term in the effective potential of the flat direction.
|
hep-ph/0610283
|
Hai-Yang Cheng
|
Hai-Yang Cheng, Chun-Khiang Chua
|
Strong Decays of Charmed Baryons in Heavy Hadron Chiral Perturbation
Theory
|
22 pages, the coupling g_2 is slightly modified, Tables 5 and 6 are
updated; version to appear in PRD
|
Phys.Rev.D75:014006,2007
|
10.1103/PhysRevD.75.014006
| null |
hep-ph hep-ex
| null |
Strong decays of charmed baryons are analyzed in the framework of heavy
hadron chiral perturbation theory (HHChPT) in which heavy quark symmetry and
chiral symmetry are synthesized. HHChPT works excellently for describing the
strong decays of s-wave charmed baryons. For L=1 orbitally excited states, two
of the unknown couplings, namely, $h_2$ and $h_{10}$, are determined from the
resonant $\Lambda_c^+\pi\pi$ mode produced in the $\Lambda_c(2593)$ decay and
the width of $\Sigma_c(2800)$, respectively. Predictions for the strong decays
of the p-wave charmed baryon states $\Lambda_c(2625)$, $\Xi_c(2790)$ and
$\Xi_c(2815)$ are presented. Since the decay
$\Lambda_c(2593)^+\to\Lambda_c^+\pi\pi$ receives non-resonant contributions,
our value for $h_2$ is smaller than the previous estimates. We also discuss the
first positive-parity excited charmed baryons. We conjecture that the charmed
baryon $\Lambda_c(2880)$ with $J^P=\frac52^+$ is an admixture of
$\Lambda_{c2}(\frac52^+)$ with and $\tilde\Lambda''_{c3}(\frac52^+)$; both are
L=2 orbitally excited states. The potential model suggests $J^P=\frac52^-$ or
$\frac32^+$ for $\Lambda_c(2940)^+$. Measurements of the ratio of
$\Sigma_c^*\pi/\Sigma_c\pi$ will enable us to discriminate the $J^P$
assignments for $\Lambda_c(2940)$. We advocate that the $J^P$ quantum numbers
of $\Xi_c(2980)$ and $\Xi_c(3077)$ are $\frac12^+$ and $\frac52^+$,
respectively. Under this $J^P$ assignment, it is ready to understand why
$\Xi_c(2980)$ is broader than $\Xi_c(3077)$.
|
[
{
"created": "Mon, 23 Oct 2006 08:48:17 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Dec 2006 09:34:08 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Cheng",
"Hai-Yang",
""
],
[
"Chua",
"Chun-Khiang",
""
]
] |
Strong decays of charmed baryons are analyzed in the framework of heavy hadron chiral perturbation theory (HHChPT) in which heavy quark symmetry and chiral symmetry are synthesized. HHChPT works excellently for describing the strong decays of s-wave charmed baryons. For L=1 orbitally excited states, two of the unknown couplings, namely, $h_2$ and $h_{10}$, are determined from the resonant $\Lambda_c^+\pi\pi$ mode produced in the $\Lambda_c(2593)$ decay and the width of $\Sigma_c(2800)$, respectively. Predictions for the strong decays of the p-wave charmed baryon states $\Lambda_c(2625)$, $\Xi_c(2790)$ and $\Xi_c(2815)$ are presented. Since the decay $\Lambda_c(2593)^+\to\Lambda_c^+\pi\pi$ receives non-resonant contributions, our value for $h_2$ is smaller than the previous estimates. We also discuss the first positive-parity excited charmed baryons. We conjecture that the charmed baryon $\Lambda_c(2880)$ with $J^P=\frac52^+$ is an admixture of $\Lambda_{c2}(\frac52^+)$ with and $\tilde\Lambda''_{c3}(\frac52^+)$; both are L=2 orbitally excited states. The potential model suggests $J^P=\frac52^-$ or $\frac32^+$ for $\Lambda_c(2940)^+$. Measurements of the ratio of $\Sigma_c^*\pi/\Sigma_c\pi$ will enable us to discriminate the $J^P$ assignments for $\Lambda_c(2940)$. We advocate that the $J^P$ quantum numbers of $\Xi_c(2980)$ and $\Xi_c(3077)$ are $\frac12^+$ and $\frac52^+$, respectively. Under this $J^P$ assignment, it is ready to understand why $\Xi_c(2980)$ is broader than $\Xi_c(3077)$.
|
2311.00450
|
Michael Klasen
|
M. Klasen, H. Paukkunen
|
Nuclear PDFs After the First Decade of LHC Data
|
Invited review, accepted by Ann. Rev. Nucl. Part. Sci. 40 pages, 3
tables, 8 figures, 1 suppl. page/figure
| null |
10.1146/annurev-nucl-102122-022747
|
MS-TP-23-45
|
hep-ph hep-ex nucl-ex nucl-th
|
http://creativecommons.org/licenses/by/4.0/
|
We present a review of the conceptual basis, present knowledge and recent
progress in the field of global analysis of nuclear parton distribution
functions (PDFs). After introducing the theoretical foundations and
methodological approaches for the extraction of nuclear PDFs from experimental
data, we discuss how different measurements in fixed-target and collider
experiments provide increasingly precise constraints on various aspects of
nuclear PDFs, including shadowing, antishadowing, the EMC effect, Fermi motion,
flavor separation, deuteron binding, target-mass and other higher-twist
effects. Particular emphasis is given to measurements carried out in
proton-lead collisions at the Large Hadron Collider, which have revolutionized
the global analysis during the past decade. These measurements include
electroweak-boson, jet, light-hadron, and heavy-flavor observables. Finally, we
outline the expected impact of the future Electron Ion Collider and discuss the
role and interplay of nuclear PDFs with other branches of nuclear, particle and
astroparticle physics.
|
[
{
"created": "Wed, 1 Nov 2023 11:27:56 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Jan 2024 16:25:28 GMT",
"version": "v2"
}
] |
2024-01-26
|
[
[
"Klasen",
"M.",
""
],
[
"Paukkunen",
"H.",
""
]
] |
We present a review of the conceptual basis, present knowledge and recent progress in the field of global analysis of nuclear parton distribution functions (PDFs). After introducing the theoretical foundations and methodological approaches for the extraction of nuclear PDFs from experimental data, we discuss how different measurements in fixed-target and collider experiments provide increasingly precise constraints on various aspects of nuclear PDFs, including shadowing, antishadowing, the EMC effect, Fermi motion, flavor separation, deuteron binding, target-mass and other higher-twist effects. Particular emphasis is given to measurements carried out in proton-lead collisions at the Large Hadron Collider, which have revolutionized the global analysis during the past decade. These measurements include electroweak-boson, jet, light-hadron, and heavy-flavor observables. Finally, we outline the expected impact of the future Electron Ion Collider and discuss the role and interplay of nuclear PDFs with other branches of nuclear, particle and astroparticle physics.
|
1901.10342
|
Simone Marzani
|
Simone Marzani, Gregory Soyez and Michael Spannowsky
|
Looking inside jets: an introduction to jet substructure and
boosted-object phenomenology
|
New 2022 (arXiv-only) version! We've corrected a mistake about soft
factorisation in section 2.3 and fixed several typos. Please let us know if
you still find something amiss, we'll be happy to fix it
|
Lecture Notes in Physics, volume 958 (2019)
|
10.1007/978-3-030-15709-8
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The study of the internal structure of hadronic jets has become in recent
years a very active area of research in particle physics. Jet substructure
techniques are increasingly used in experimental analyses by the LHC
collaborations, both in the context of searching for new physics and for
Standard Model measurements. On the theory side, the quest for a deeper
understanding of jet substructure algorithms has contributed to a renewed
interest in all-order calculations in QCD. This has resulted in new ideas about
how to design better observables and how to provide a solid theoretical
description for them. In the last years, jet substructure has seen its scope
extended, for example, with an increasing impact in the study of heavy-ion
collisions, or with the exploration of deep-learning techniques. Furthermore,
jet physics is an area in which experimental and theoretical approaches meet
together, where cross-pollination and collaboration between the two communities
often bear the fruits of innovative techniques. Despite the wealth of
literature on this topic, we feel that a comprehensive and, at the same time,
pedagogical introduction to jet substructure is still missing. This makes the
endeavour of approaching the field particularly hard, as newcomers have to
digest an increasing number of substructure algorithms and techniques, too
often characterised by opaque terminology and jargon. Furthermore, while
first-principle calculations in QCD have successfully been applied in order to
understand and characterise the substructure of jets, they often make use of
calculational techniques, such as resummation, which are not the usual textbook
material. Thus, the idea of combining our experience in different aspects of
jet substructure phenomenology to put together this set of lecture notes, which
we hope could help and guide someone who moves their first steps in the physics
of jet substructure.
|
[
{
"created": "Tue, 29 Jan 2019 15:37:15 GMT",
"version": "v1"
},
{
"created": "Mon, 13 May 2019 15:04:46 GMT",
"version": "v2"
},
{
"created": "Mon, 17 Feb 2020 16:30:49 GMT",
"version": "v3"
},
{
"created": "Sat, 9 Jul 2022 13:22:24 GMT",
"version": "v4"
}
] |
2022-07-12
|
[
[
"Marzani",
"Simone",
""
],
[
"Soyez",
"Gregory",
""
],
[
"Spannowsky",
"Michael",
""
]
] |
The study of the internal structure of hadronic jets has become in recent years a very active area of research in particle physics. Jet substructure techniques are increasingly used in experimental analyses by the LHC collaborations, both in the context of searching for new physics and for Standard Model measurements. On the theory side, the quest for a deeper understanding of jet substructure algorithms has contributed to a renewed interest in all-order calculations in QCD. This has resulted in new ideas about how to design better observables and how to provide a solid theoretical description for them. In the last years, jet substructure has seen its scope extended, for example, with an increasing impact in the study of heavy-ion collisions, or with the exploration of deep-learning techniques. Furthermore, jet physics is an area in which experimental and theoretical approaches meet together, where cross-pollination and collaboration between the two communities often bear the fruits of innovative techniques. Despite the wealth of literature on this topic, we feel that a comprehensive and, at the same time, pedagogical introduction to jet substructure is still missing. This makes the endeavour of approaching the field particularly hard, as newcomers have to digest an increasing number of substructure algorithms and techniques, too often characterised by opaque terminology and jargon. Furthermore, while first-principle calculations in QCD have successfully been applied in order to understand and characterise the substructure of jets, they often make use of calculational techniques, such as resummation, which are not the usual textbook material. Thus, the idea of combining our experience in different aspects of jet substructure phenomenology to put together this set of lecture notes, which we hope could help and guide someone who moves their first steps in the physics of jet substructure.
|
hep-ph/0309303
|
Agnieszka Gawron
|
Agnieszka Gawron, Jan Kwiecinski
|
Resummation effects in Higgs boson transverse momentum distribution
within the framework of unintegrated parton distributions
|
22 pages, 5 figures
|
Phys.Rev. D70 (2004) 014003
|
10.1103/PhysRevD.70.014003
| null |
hep-ph
| null |
The cross sections describing the transverse momentum distributions of Higgs
bosons are discussed within the framework of unintegrated parton distributions
obtained from the CCFM equations in the single loop approximation. It is shown
how the approximate treatment of the CCFM equations generates the standard
expressions describing the soft gluon resummation effects in the corresponding
cross sections. Possible differences between exact and approximate solutions of
the CCFM equations are discussed on the example of the gg -> H fusion
mechanism, which gives the dominant contribution to Higgs production.
|
[
{
"created": "Fri, 26 Sep 2003 09:41:03 GMT",
"version": "v1"
}
] |
2009-11-10
|
[
[
"Gawron",
"Agnieszka",
""
],
[
"Kwiecinski",
"Jan",
""
]
] |
The cross sections describing the transverse momentum distributions of Higgs bosons are discussed within the framework of unintegrated parton distributions obtained from the CCFM equations in the single loop approximation. It is shown how the approximate treatment of the CCFM equations generates the standard expressions describing the soft gluon resummation effects in the corresponding cross sections. Possible differences between exact and approximate solutions of the CCFM equations are discussed on the example of the gg -> H fusion mechanism, which gives the dominant contribution to Higgs production.
|
hep-ph/0605046
|
Andrew Buckley
|
A. Buckley (1), J. M. Butterworth (2), E. Nurse (2), W. J. Stirling
(1), B. Waugh (2), M. R. Whalley (1) ((1) IPPP, Durham University, England,
(2) University College London, England)
|
HepForge: A lightweight development environment for HEP software
|
3 pages, 0 figures. To be published in proceedings of CHEP06. Refers
to the HepForge facility at http://hepforge.cedar.ac.uk
| null | null | null |
hep-ph
| null |
Setting up the infrastructure to manage a software project can become a task
as significant writing the software itself. A variety of useful open source
tools are available, such as Web-based viewers for version control systems,
"wikis" for collaborative discussions and bug-tracking systems, but their use
in high-energy physics, outside large collaborations, is insubstantial.
Understandably, physicists would rather do physics than configure project
management tools.
We introduce the CEDAR HepForge system, which provides a lightweight
development environment for HEP software. Services available as part of
HepForge include the above-mentioned tools as well as mailing lists, shell
accounts, archiving of releases and low-maintenance Web space. HepForge also
exists to promote best-practice software development methods and to provide a
central repository for re-usable HEP software and phenomenology codes.
|
[
{
"created": "Thu, 4 May 2006 16:32:07 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Buckley",
"A.",
""
],
[
"Butterworth",
"J. M.",
""
],
[
"Nurse",
"E.",
""
],
[
"Stirling",
"W. J.",
""
],
[
"Waugh",
"B.",
""
],
[
"Whalley",
"M. R.",
""
]
] |
Setting up the infrastructure to manage a software project can become a task as significant writing the software itself. A variety of useful open source tools are available, such as Web-based viewers for version control systems, "wikis" for collaborative discussions and bug-tracking systems, but their use in high-energy physics, outside large collaborations, is insubstantial. Understandably, physicists would rather do physics than configure project management tools. We introduce the CEDAR HepForge system, which provides a lightweight development environment for HEP software. Services available as part of HepForge include the above-mentioned tools as well as mailing lists, shell accounts, archiving of releases and low-maintenance Web space. HepForge also exists to promote best-practice software development methods and to provide a central repository for re-usable HEP software and phenomenology codes.
|
1205.0545
|
Skokov Vladimir
|
Kouji Kashiwa, Robert D. Pisarski, Vladimir V. Skokov
|
Critical endpoint for deconfinement in matrix and other effective models
|
16 pages; 3 figures
| null |
10.1103/PhysRevD.85.114029
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider the position of the deconfining critical endpoint, where the
first order transition for deconfinement is washed out by the presence of
massive, dynamical quarks. We use an effective matrix model, employed
previously to analyze the transition in the pure glue theory. If the param-
eters of the pure glue theory are unaffected by the presence of dynamical
quarks, and if the quarks only contribute perturbatively, then for three colors
and three degenerate quark flavors this quark mass is very heavy, m_de \sim 2.5
GeV, while the critical temperature, T_de, barely changes, \sim 1% below that
in the pure glue theory. The location of the deconfining critical endpoint is a
sensitive test to differentiate between effective models. For example, models
with a logarithmic potential for the Polyakov loop give much smaller values of
the quark mass, m_de \sim 1 GeV, and a large shift in T_de \sim 10% lower than
that in the pure glue theory.
|
[
{
"created": "Wed, 2 May 2012 20:00:01 GMT",
"version": "v1"
}
] |
2013-05-30
|
[
[
"Kashiwa",
"Kouji",
""
],
[
"Pisarski",
"Robert D.",
""
],
[
"Skokov",
"Vladimir V.",
""
]
] |
We consider the position of the deconfining critical endpoint, where the first order transition for deconfinement is washed out by the presence of massive, dynamical quarks. We use an effective matrix model, employed previously to analyze the transition in the pure glue theory. If the param- eters of the pure glue theory are unaffected by the presence of dynamical quarks, and if the quarks only contribute perturbatively, then for three colors and three degenerate quark flavors this quark mass is very heavy, m_de \sim 2.5 GeV, while the critical temperature, T_de, barely changes, \sim 1% below that in the pure glue theory. The location of the deconfining critical endpoint is a sensitive test to differentiate between effective models. For example, models with a logarithmic potential for the Polyakov loop give much smaller values of the quark mass, m_de \sim 1 GeV, and a large shift in T_de \sim 10% lower than that in the pure glue theory.
|
1106.3368
|
Stefano Profumo
|
M. S. Boucenna and S. Profumo
|
Direct and Indirect Singlet Scalar Dark Matter Detection in the
Lepton-Specific two-Higgs-doublet Model
|
16 pages, 3 figures; v2: references and comments added, figures
re-styled, to appear on PRD
| null |
10.1103/PhysRevD.84.055011
| null |
hep-ph astro-ph.CO astro-ph.HE
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A recent study of gamma-ray data from the Galactic Center motivates the
investigation of light (~7-10 GeV) particle dark matter models featuring tau
lepton pairs as dominant annihilation final state. The Lepton-Specific
two-Higgs-doublet Model (2HDM-L) provides a natural framework where light,
singlet scalar dark matter can pair-annihilate dominantly into tau leptons. We
calculate the nucleon-dark matter cross section for singlet scalar dark matter
within the 2HDM-L framework, and compare with recent results from direct
detection experiments. We study how direct dark matter searches can be used to
constrain the dark matter interpretation of gamma ray observations, for
different dominant annihilation final states. We show that models exist with
the correct thermal relic abundance that could fit the claimed gamma-ray excess
from the Galactic Center region and have direct detection cross sections of the
order of what needed to interpret recent anomalous events reported by direct
detection experiments.
|
[
{
"created": "Thu, 16 Jun 2011 23:01:08 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Aug 2011 21:40:58 GMT",
"version": "v2"
}
] |
2015-05-28
|
[
[
"Boucenna",
"M. S.",
""
],
[
"Profumo",
"S.",
""
]
] |
A recent study of gamma-ray data from the Galactic Center motivates the investigation of light (~7-10 GeV) particle dark matter models featuring tau lepton pairs as dominant annihilation final state. The Lepton-Specific two-Higgs-doublet Model (2HDM-L) provides a natural framework where light, singlet scalar dark matter can pair-annihilate dominantly into tau leptons. We calculate the nucleon-dark matter cross section for singlet scalar dark matter within the 2HDM-L framework, and compare with recent results from direct detection experiments. We study how direct dark matter searches can be used to constrain the dark matter interpretation of gamma ray observations, for different dominant annihilation final states. We show that models exist with the correct thermal relic abundance that could fit the claimed gamma-ray excess from the Galactic Center region and have direct detection cross sections of the order of what needed to interpret recent anomalous events reported by direct detection experiments.
|
hep-ph/0306172
|
Makoto Oka
|
Makoto Oka
|
Summary of the YITP-RCNP Workshop on Chiral Restoration in Nuclear
Medium
|
Summary talk of the YITP-RCNP Workshop on Chiral Restoration in
Nuclear Medium (October 7-9, 2002)
|
Prog.Theor.Phys.Suppl. 149 (2003) 286-292
|
10.1143/PTPS.149.286
|
TIT/HEP/NP-101
|
hep-ph
| null |
This is a personal summary of the workshop. I overview the topics of the
workshop and itemize what we learned at the workshop.
|
[
{
"created": "Thu, 19 Jun 2003 07:29:46 GMT",
"version": "v1"
}
] |
2009-11-10
|
[
[
"Oka",
"Makoto",
""
]
] |
This is a personal summary of the workshop. I overview the topics of the workshop and itemize what we learned at the workshop.
|
2209.07866
|
Juan Antonio Aguilar-Saavedra
|
J. A. Aguilar-Saavedra
|
Understanding template methods for top polarisation measurements
|
Talk at the 15th International Workshop on Top Quark Physics, Durham,
UK, 4-9 September 2022
| null | null |
IFT-UAM/CSIC-22-103
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Top polarisation measurements at the LHC are often performed using template
methods. I discuss the role of quantum interference between polarisation states
- which is mostly overlooked in the literature. Furthermore, I argue which is
the correct definition of the `templates' of definite polarisations, in order
to match the experimental measurements with meaningful theoretical predictions.
|
[
{
"created": "Fri, 16 Sep 2022 11:40:21 GMT",
"version": "v1"
}
] |
2022-09-19
|
[
[
"Aguilar-Saavedra",
"J. A.",
""
]
] |
Top polarisation measurements at the LHC are often performed using template methods. I discuss the role of quantum interference between polarisation states - which is mostly overlooked in the literature. Furthermore, I argue which is the correct definition of the `templates' of definite polarisations, in order to match the experimental measurements with meaningful theoretical predictions.
|
1012.1327
|
Jorge de Blas Mateo
|
Francisco del Aguila, Juan Antonio Aguilar-Saavedra, Jorge de Blas
|
New neutrino interactions at large colliders
|
Latex 4 pages, 4 eps figures. Contribution to the Proceedings of the
35th International Conference of High Energy Physics - ICHEP2010, Paris,
France, July 22-28, 2010
|
PoS ICHEP2010:296,2010
| null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We update present bounds on the helicity of the neutrinos produced in muon
decay, including e+ e- -> fbar f LEP 2 data. These significantly reduce the
limits derived from all the other electroweak precision data. In Standard Model
extensions designed to maximize the RH neutrino production in such a decay the
neutrino deficit eventually observable in a near detector at a neutrino factory
can be of the order of 5 %. Motivated by the current LHC run at 7 TeV, we also
update previous work providing discovery limits on see-saw mediators at this
centre of mass energy. Lepton triplets with 200 GeV could be discovered with
luminosities of 1 - 1.5 fb^-1. Scalar triplets of the same mass might be seen
with 0.75 - 3 fb^-1. What makes their search also attractive in the first LHC
analyses.
|
[
{
"created": "Mon, 6 Dec 2010 21:04:12 GMT",
"version": "v1"
}
] |
2015-03-17
|
[
[
"del Aguila",
"Francisco",
""
],
[
"Aguilar-Saavedra",
"Juan Antonio",
""
],
[
"de Blas",
"Jorge",
""
]
] |
We update present bounds on the helicity of the neutrinos produced in muon decay, including e+ e- -> fbar f LEP 2 data. These significantly reduce the limits derived from all the other electroweak precision data. In Standard Model extensions designed to maximize the RH neutrino production in such a decay the neutrino deficit eventually observable in a near detector at a neutrino factory can be of the order of 5 %. Motivated by the current LHC run at 7 TeV, we also update previous work providing discovery limits on see-saw mediators at this centre of mass energy. Lepton triplets with 200 GeV could be discovered with luminosities of 1 - 1.5 fb^-1. Scalar triplets of the same mass might be seen with 0.75 - 3 fb^-1. What makes their search also attractive in the first LHC analyses.
|
2305.17025
|
Khushboo Dixit
|
Khushboo Dixit, S. Shajidul Haque, Soebur Razzaque
|
Quantum Spread Complexity in Neutrino Oscillations
|
29 pages, 9 figures, Accepted for publication in Eur. Phys. J. C
|
Eur. Phys. J. C (2024) 84:260
|
10.1140/epjc/s10052-024-12620-0
| null |
hep-ph hep-ex hep-th quant-ph
|
http://creativecommons.org/licenses/by/4.0/
|
Quantum information theory has recently emerged as a flourishing area of
research and quantum complexity, one of its powerful measures, is being applied
for investigating complex systems in many areas of physics. Its application to
practical physical situations, however, is still few and far between. Neutrino
flavor oscillation is a widely studied physical phenomena with far reaching
consequences in understanding the standard model of particle physics and to
search for physics beyond it. Oscillation arises because of mixing between the
flavor and mass eigenstates, and their evolution over time. It is an inherent
quantum system for which flavor transitions are traditionally studied with
probabilistic measures. We have applied quantum complexity formalism as an
alternate measure to study neutrino oscillations. In particular, quantum spread
complexity revealed additional information on the violation of charge-parity
symmetry in the neutrino sector. Our results indicate that complexity favors
the maximum violation of charge-parity, hinted recently by experimental data.
|
[
{
"created": "Fri, 26 May 2023 15:34:31 GMT",
"version": "v1"
},
{
"created": "Sun, 24 Dec 2023 16:58:46 GMT",
"version": "v2"
},
{
"created": "Mon, 26 Feb 2024 20:37:01 GMT",
"version": "v3"
}
] |
2024-03-14
|
[
[
"Dixit",
"Khushboo",
""
],
[
"Haque",
"S. Shajidul",
""
],
[
"Razzaque",
"Soebur",
""
]
] |
Quantum information theory has recently emerged as a flourishing area of research and quantum complexity, one of its powerful measures, is being applied for investigating complex systems in many areas of physics. Its application to practical physical situations, however, is still few and far between. Neutrino flavor oscillation is a widely studied physical phenomena with far reaching consequences in understanding the standard model of particle physics and to search for physics beyond it. Oscillation arises because of mixing between the flavor and mass eigenstates, and their evolution over time. It is an inherent quantum system for which flavor transitions are traditionally studied with probabilistic measures. We have applied quantum complexity formalism as an alternate measure to study neutrino oscillations. In particular, quantum spread complexity revealed additional information on the violation of charge-parity symmetry in the neutrino sector. Our results indicate that complexity favors the maximum violation of charge-parity, hinted recently by experimental data.
|
hep-ph/0702129
|
Manmohan Gupta
|
Gulsheen Ahuja and Manmohan Gupta
|
Constructing the Leptonic Unitarity Triangle
|
8 pages, 2 figures
|
Phys.Rev.D77:057301,2008
|
10.1103/PhysRevD.77.057301
| null |
hep-ph
| null |
Following analogy of the `db' triangle in the quark mixing case, we have
explored the construction of the `\nu_2.\nu_3' leptonic unitarity triangle
using the Maki-Nakagawa-Sakata matrix obtained by Bjorken {\it et al.} through
generalization of the tribimaximal scenario. In particular, for the U_{e3}
range 0.05-0.15, the existence of the leptonic unitarity triangle indicates a
fairly good possibility of having non zero CP violation.
|
[
{
"created": "Tue, 13 Feb 2007 07:11:12 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Apr 2008 05:32:26 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Ahuja",
"Gulsheen",
""
],
[
"Gupta",
"Manmohan",
""
]
] |
Following analogy of the `db' triangle in the quark mixing case, we have explored the construction of the `\nu_2.\nu_3' leptonic unitarity triangle using the Maki-Nakagawa-Sakata matrix obtained by Bjorken {\it et al.} through generalization of the tribimaximal scenario. In particular, for the U_{e3} range 0.05-0.15, the existence of the leptonic unitarity triangle indicates a fairly good possibility of having non zero CP violation.
|
0904.4108
|
Joao G. Rosa
|
Babiker Hassanain, John March-Russell and J. G. Rosa
|
On the possibility of light string resonances at the LHC and Tevatron
from Randall-Sundrum throats
|
17 pages, 6 figures Version published in JHEP with minor corrections
|
JHEP 0907:077,2009
|
10.1088/1126-6708/2009/07/077
|
OUTP-09-11
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In string realizations of the Randall-Sundrum scenario, the higher-spin Regge
excitations of Standard Model states localized near the IR brane are warped
down to close to the TeV scale. We argue that, as a consequence of the
localization properties of Randall-Sundrum models of flavour, the lightest such
resonance is the spin-3/2 excitation of the right-handed top quark over a
significant region of parameter space. A mild accidental cancellation allows
this resonance to be as light or lighter than the Kaluza-Klein excitations of
the Standard Model states. We consider from a bottom-up effective theory point
of view the production and possible observability of such a spin-3/2 excitation
at the LHC and Tevatron. Current limits are weaker than might be expected
because of the excess of WWjj events at the Tevatron reported by CDF for an
invariant mass of 400-500 GeV.
|
[
{
"created": "Mon, 27 Apr 2009 14:47:50 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Jul 2009 11:30:37 GMT",
"version": "v2"
}
] |
2009-08-11
|
[
[
"Hassanain",
"Babiker",
""
],
[
"March-Russell",
"John",
""
],
[
"Rosa",
"J. G.",
""
]
] |
In string realizations of the Randall-Sundrum scenario, the higher-spin Regge excitations of Standard Model states localized near the IR brane are warped down to close to the TeV scale. We argue that, as a consequence of the localization properties of Randall-Sundrum models of flavour, the lightest such resonance is the spin-3/2 excitation of the right-handed top quark over a significant region of parameter space. A mild accidental cancellation allows this resonance to be as light or lighter than the Kaluza-Klein excitations of the Standard Model states. We consider from a bottom-up effective theory point of view the production and possible observability of such a spin-3/2 excitation at the LHC and Tevatron. Current limits are weaker than might be expected because of the excess of WWjj events at the Tevatron reported by CDF for an invariant mass of 400-500 GeV.
|
1502.02263
|
Jean-Philippe Lansberg
|
J.P. Lansberg
|
Back-to-back isolated photon-quarkonium production at the LHC and the
transverse-momentum-dependent distributions of the gluons in the proton
|
LaTeX, 6 pages, 4 figures, uses ws-ijmpcs.cls (included).
Contribution to the proceedings of the 21st International Symposium on Spin
Physics (SPIN2014), October 20-24, 2014, Beijing, China
| null |
10.1142/S2010194516600156
| null |
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The study of a quasi back-to-back isolated pair made of a heavy quarkonium,
such as a J/psi or a Upsilon, and a photon produced in proton-proton collisions
at the LHC, is probably the optimal way to get right away a first experimental
determination of two gluon transverse-momentum-dependent distributions (TMDs)
in an unpolarized proton, f1^g and h1^perp,g the latter giving the distribution
of linearly polarized gluons. To substantiate this, we calculate the
transverse-momentum-dependent effects that arise in the process under study and
discuss the feasibility of their measurements.
|
[
{
"created": "Sun, 8 Feb 2015 15:17:08 GMT",
"version": "v1"
}
] |
2016-03-23
|
[
[
"Lansberg",
"J. P.",
""
]
] |
The study of a quasi back-to-back isolated pair made of a heavy quarkonium, such as a J/psi or a Upsilon, and a photon produced in proton-proton collisions at the LHC, is probably the optimal way to get right away a first experimental determination of two gluon transverse-momentum-dependent distributions (TMDs) in an unpolarized proton, f1^g and h1^perp,g the latter giving the distribution of linearly polarized gluons. To substantiate this, we calculate the transverse-momentum-dependent effects that arise in the process under study and discuss the feasibility of their measurements.
|
1401.4327
|
Akbari Jahan
|
Akbari Jahan and D. K. Choudhury
|
Self-similarity and the Froissart bound
|
11 pages, 2 figures, 1 table
|
Phys. Rev. D 89, 014014 (2014)
|
10.1103/PhysRevD.89.014014
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The Froissart bound implies that the total cross section (or, equivalently,
the structure function) cannot rise faster than the logarithmic growth of $
\ln^{2} \left(\frac{1}{x} \right)$. In this work, we show that such a slow
growth is not compatible with the notion of self-similarity. As a result, it
calls for the modification of the defining transverse-momentum-dependent parton
density function (TMD PDF) of a self-similarity based proton structure function
$F_{2} \left(x,Q^{2} \right)$ at small \textit{x}. Using plausible assumptions,
we obtain the Froissart saturation condition on this TMD PDF.
|
[
{
"created": "Fri, 17 Jan 2014 12:54:12 GMT",
"version": "v1"
}
] |
2014-01-20
|
[
[
"Jahan",
"Akbari",
""
],
[
"Choudhury",
"D. K.",
""
]
] |
The Froissart bound implies that the total cross section (or, equivalently, the structure function) cannot rise faster than the logarithmic growth of $ \ln^{2} \left(\frac{1}{x} \right)$. In this work, we show that such a slow growth is not compatible with the notion of self-similarity. As a result, it calls for the modification of the defining transverse-momentum-dependent parton density function (TMD PDF) of a self-similarity based proton structure function $F_{2} \left(x,Q^{2} \right)$ at small \textit{x}. Using plausible assumptions, we obtain the Froissart saturation condition on this TMD PDF.
|
hep-ph/0206251
|
Xavier Calmet
|
X. Calmet
|
A Duality as a Theory for the Electroweak Interactions
|
Ph.D. thesis
|
Shaker Verlag Aachen 2002, ISBN 3-8322-0324-9.
| null |
LMU 02/06
|
hep-ph
| null |
We present a model based on a SU(2) confining theory which is dual to the
standard model. This duality allows to calculate the electroweak mixing angle
and the Higgs boson mass. Possible tests of this duality are discussed.
|
[
{
"created": "Tue, 25 Jun 2002 11:29:34 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Calmet",
"X.",
""
]
] |
We present a model based on a SU(2) confining theory which is dual to the standard model. This duality allows to calculate the electroweak mixing angle and the Higgs boson mass. Possible tests of this duality are discussed.
|
hep-ph/0007255
|
Piotr Chankowski
|
W. Krolikowski (Warsaw Univ.)
|
Two-mixing texture for three active neutrinos
|
9 pages, no figures
| null | null |
IFT 00/15
|
hep-ph
| null |
The conjecture that among three massive neutrinos $\nu_1, \nu_2, \nu_3$ there
is no direct mixing between $\nu_1$ and $\nu_3$ leads to a two-mixing texture
for three active neutrinos $\nu_e, \nu_\mu, \nu_\tau$. This texture, much
discussed previously, is neatly consistent with the observed deficits of solar
$\nu_e$'s and atmospheric $\nu_\mu$'s, but (without extra mixing with at least
one sterile neutrino $\nu_s$) predicts no LSND effect for accelerator
$\nu_\mu$'s. In this option, the masses $m^2_1\stackrel{<}{\sim} m^2_2 <<
m^2_3$ are readily estimated. The characteristic feature of the two-mixing
neutrino texture that {\it only the close neighbours in the hierarchy of
massive neutrinos $\nu_1, \nu_2, \nu_3$ mix significantly} may be physically
meaningful. Going out from the notion of mixing matrix we construct an
intrinsic occupation-number operator whose {\it eigenvalues} 0, 1, 2 {\it
numerate the three generations of massive neutrinos}. Analogical constructions
work also for charged leptons as well as for up and down quarks.
|
[
{
"created": "Mon, 24 Jul 2000 11:03:41 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Krolikowski",
"W.",
"",
"Warsaw Univ."
]
] |
The conjecture that among three massive neutrinos $\nu_1, \nu_2, \nu_3$ there is no direct mixing between $\nu_1$ and $\nu_3$ leads to a two-mixing texture for three active neutrinos $\nu_e, \nu_\mu, \nu_\tau$. This texture, much discussed previously, is neatly consistent with the observed deficits of solar $\nu_e$'s and atmospheric $\nu_\mu$'s, but (without extra mixing with at least one sterile neutrino $\nu_s$) predicts no LSND effect for accelerator $\nu_\mu$'s. In this option, the masses $m^2_1\stackrel{<}{\sim} m^2_2 << m^2_3$ are readily estimated. The characteristic feature of the two-mixing neutrino texture that {\it only the close neighbours in the hierarchy of massive neutrinos $\nu_1, \nu_2, \nu_3$ mix significantly} may be physically meaningful. Going out from the notion of mixing matrix we construct an intrinsic occupation-number operator whose {\it eigenvalues} 0, 1, 2 {\it numerate the three generations of massive neutrinos}. Analogical constructions work also for charged leptons as well as for up and down quarks.
|
1911.02264
|
Mansour Haghighat
|
S. Modares Vamegh, M. Haghighat, S. Mahmoudi and R. Mohammadi
|
Impact of the vector dark matter on polarization of the CMB photon
|
40 pages, 7 figures, Accepted for publication in Physical Review D
| null |
10.1103/PhysRevD.100.103024
| null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider a vector dark matter (VDM) with a direct coupling with photon. We
examine the effect of such an interaction on the CMB polarization to put new
constrains on the properties of the DM particles. We show that a partially
polarized VDM of the order of temperature fluctuation with a quadrupole
distribution leads to a valuable CP for the CMB. In different DM-models the
DM-masses range from few $eV$ to a few $TeV$. We show that the CP angular power
spectrum depends on the mass of VDM as $C^{(S)}_{Vl}\propto 1/m_{_{V}}^6$ such
that for $m_{_{V}}=10eV-1keV$, the CP angular power spectrum is
$C^{(S)}_{Vl}\simeq 10^3- 10^{-11}{\rm nK^2}$. Therefore, the light VDM with
masses less than $10 eV$ leads to an unexpected very large CP which can be
excluded from the acceptable range of the VDM masses.
|
[
{
"created": "Wed, 6 Nov 2019 09:27:30 GMT",
"version": "v1"
}
] |
2020-01-08
|
[
[
"Vamegh",
"S. Modares",
""
],
[
"Haghighat",
"M.",
""
],
[
"Mahmoudi",
"S.",
""
],
[
"Mohammadi",
"R.",
""
]
] |
We consider a vector dark matter (VDM) with a direct coupling with photon. We examine the effect of such an interaction on the CMB polarization to put new constrains on the properties of the DM particles. We show that a partially polarized VDM of the order of temperature fluctuation with a quadrupole distribution leads to a valuable CP for the CMB. In different DM-models the DM-masses range from few $eV$ to a few $TeV$. We show that the CP angular power spectrum depends on the mass of VDM as $C^{(S)}_{Vl}\propto 1/m_{_{V}}^6$ such that for $m_{_{V}}=10eV-1keV$, the CP angular power spectrum is $C^{(S)}_{Vl}\simeq 10^3- 10^{-11}{\rm nK^2}$. Therefore, the light VDM with masses less than $10 eV$ leads to an unexpected very large CP which can be excluded from the acceptable range of the VDM masses.
|
2401.17253
|
Ken'ichi Saikawa
|
Ken'ichi Saikawa, Javier Redondo, Alejandro Vaquero, Mathieu
Kaltschmidt
|
Spectrum of global string networks and the axion dark matter mass
|
51 pages, 46 figures
| null | null |
KANAZAWA-24-02, MPP-2024-18
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Cold dark matter axions produced in the post-inflationary Peccei-Quinn
symmetry breaking scenario serve as clear targets for their experimental
detection, since it is in principle possible to give a sharp prediction for
their mass once we understand precisely how they are produced from the decay of
global cosmic strings in the early Universe. In this paper, we perform a
dedicated analysis of the spectrum of axions radiated from strings based on
large scale numerical simulations of the cosmological evolution of the
Peccei-Quinn field on a static lattice. Making full use of the massively
parallel code and computing resources, we executed the simulations with up to
$11264^3$ lattice sites, which allows us to improve our understanding of the
dependence on the parameter controlling the string tension and thus give a more
accurate extrapolation of the numerical results. We found that there are
several systematic effects that have been overlooked in previous works, such as
the dependence on the initial conditions, contaminations due to oscillations in
the spectrum, and discretisation effects, some of which could explain the
discrepancy in the literature. We confirmed the trend that the spectral index
of the axion emission spectrum increases with the string tension, but did not
find a clear evidence of whether it continues to increase or saturates to a
constant at larger values of the string tension due to the severe
discretisation effects. Taking this uncertainty into account and performing the
extrapolation with a simple power law assumption on the spectrum, we find that
the dark matter mass is predicted in the range of $m_a \approx
95$-$450\,\mu\mathrm{eV}$.
|
[
{
"created": "Tue, 30 Jan 2024 18:45:05 GMT",
"version": "v1"
}
] |
2024-01-31
|
[
[
"Saikawa",
"Ken'ichi",
""
],
[
"Redondo",
"Javier",
""
],
[
"Vaquero",
"Alejandro",
""
],
[
"Kaltschmidt",
"Mathieu",
""
]
] |
Cold dark matter axions produced in the post-inflationary Peccei-Quinn symmetry breaking scenario serve as clear targets for their experimental detection, since it is in principle possible to give a sharp prediction for their mass once we understand precisely how they are produced from the decay of global cosmic strings in the early Universe. In this paper, we perform a dedicated analysis of the spectrum of axions radiated from strings based on large scale numerical simulations of the cosmological evolution of the Peccei-Quinn field on a static lattice. Making full use of the massively parallel code and computing resources, we executed the simulations with up to $11264^3$ lattice sites, which allows us to improve our understanding of the dependence on the parameter controlling the string tension and thus give a more accurate extrapolation of the numerical results. We found that there are several systematic effects that have been overlooked in previous works, such as the dependence on the initial conditions, contaminations due to oscillations in the spectrum, and discretisation effects, some of which could explain the discrepancy in the literature. We confirmed the trend that the spectral index of the axion emission spectrum increases with the string tension, but did not find a clear evidence of whether it continues to increase or saturates to a constant at larger values of the string tension due to the severe discretisation effects. Taking this uncertainty into account and performing the extrapolation with a simple power law assumption on the spectrum, we find that the dark matter mass is predicted in the range of $m_a \approx 95$-$450\,\mu\mathrm{eV}$.
|
1008.3162
|
Li Lin Yang
|
Valentin Ahrens, Thomas Becher, Matthias Neubert and Li Lin Yang
|
Updated Predictions for Higgs Production at the Tevatron and the LHC
|
8 pages, 2 figures. v2: combined PDF+alpha_s uncertainties included;
results using NNPDF2.0 added; upgrade CTEQ6.6->CT10
|
Phys.Lett.B698:271-274,2011
|
10.1016/j.physletb.2010.12.072
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present updated predictions for the total cross section for Higgs boson
production through gluon fusion at hadron colliders. In addition to
renormalization-group improvement at next-to-next-to-next-to-leading
logarithmic accuracy, we incorporate the two-loop electroweak corrections,
which leads to the most precise predictions at present. Numerical results are
given for Higgs masses between 115 GeV and 200 GeV at the Tevatron with
\sqrt{s}=1.96 TeV and the LHC with \sqrt{s}=7-14 TeV.
|
[
{
"created": "Wed, 18 Aug 2010 20:00:16 GMT",
"version": "v1"
},
{
"created": "Sun, 5 Sep 2010 20:35:38 GMT",
"version": "v2"
}
] |
2011-04-05
|
[
[
"Ahrens",
"Valentin",
""
],
[
"Becher",
"Thomas",
""
],
[
"Neubert",
"Matthias",
""
],
[
"Yang",
"Li Lin",
""
]
] |
We present updated predictions for the total cross section for Higgs boson production through gluon fusion at hadron colliders. In addition to renormalization-group improvement at next-to-next-to-next-to-leading logarithmic accuracy, we incorporate the two-loop electroweak corrections, which leads to the most precise predictions at present. Numerical results are given for Higgs masses between 115 GeV and 200 GeV at the Tevatron with \sqrt{s}=1.96 TeV and the LHC with \sqrt{s}=7-14 TeV.
|
1206.2168
|
Gosta Gustafson
|
G\"osta Gustafson
|
Parton Cascades, Small x, and Saturation in High Energy Collisions
|
Lecture notes combining two lectures and a contribution to the
celebration of Andrzej Bia{\l}as' birthday, presented at the LI Cracow School
of Theoretical Physics, Zakopane, June 2011
| null | null |
LU-TP 12-10
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
These lecture notes are a combination of two lectures and a contribution to
the celebration of Andrzej Bia{\l}as' birthday at the LI Cracow School of
Theoretical Physics in June 2011. I here discuss the dynamics of particle
production in high energy reactions. It includes parton cascades and
hadronization in e+e--ann., small x evolution including the Double Leading Log
approximation and the BFKL equation, saturation at high densities and the BK
equation, and finally the Lund Dipole Cascade model for high energy collisions,
which is implemented in the DIPSY MC.
|
[
{
"created": "Mon, 11 Jun 2012 11:48:36 GMT",
"version": "v1"
}
] |
2012-06-12
|
[
[
"Gustafson",
"Gösta",
""
]
] |
These lecture notes are a combination of two lectures and a contribution to the celebration of Andrzej Bia{\l}as' birthday at the LI Cracow School of Theoretical Physics in June 2011. I here discuss the dynamics of particle production in high energy reactions. It includes parton cascades and hadronization in e+e--ann., small x evolution including the Double Leading Log approximation and the BFKL equation, saturation at high densities and the BK equation, and finally the Lund Dipole Cascade model for high energy collisions, which is implemented in the DIPSY MC.
|
hep-ph/9911214
|
Pasquale Di Bari
|
P.Di Bari
|
Amplification of Isocurvature Perturbations induced by Active-Sterile
Neutrino Oscillations
|
20 pages + 3 included ps figures
|
Phys.Lett. B482 (2000) 150-160
|
10.1016/S0370-2693(00)00487-1
|
INFN-ROMA1-1278/99
|
hep-ph astro-ph
| null |
We show how the generation of a lepton number in the Early Universe induced
by active-sterile neutrino oscillations, in presence of small baryon number
inhomogeneities, gives rise to the formation of lepton domains, regions with
different values of active neutrino chemical potential. The structure of these
domains reflects the spectral features of the baryon number inhomogeneities
that generated it. An interesting aspect of the mechanism is that the size of
lepton domains can be super-horizon.
|
[
{
"created": "Wed, 3 Nov 1999 16:52:30 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Di Bari",
"P.",
""
]
] |
We show how the generation of a lepton number in the Early Universe induced by active-sterile neutrino oscillations, in presence of small baryon number inhomogeneities, gives rise to the formation of lepton domains, regions with different values of active neutrino chemical potential. The structure of these domains reflects the spectral features of the baryon number inhomogeneities that generated it. An interesting aspect of the mechanism is that the size of lepton domains can be super-horizon.
|
hep-ph/0311240
|
Kenji Kadota
|
Kenji Kadota, Ewan D. Stewart
|
Inflation on Moduli Space and Cosmic Perturbations
|
23 pages, 4 figures; Added Fig. 1 and re-emphasis on dynamical
selection of desirable initial angles for inflaton modulus. To be published
in JHEP
|
JHEP 0312 (2003) 008
|
10.1088/1126-6708/2003/12/008
|
KAIST-TH2003/09, UCB-PTH-03/27
|
hep-ph astro-ph hep-th
| null |
We show that a moduli space of the form predicted by string theory, lifted by
supersymmetry breaking, gives rise to successful inflation for large regions of
parameter space without any modification or fine tuning. This natural
realization of inflation relies crucially on the complex nature of the moduli
fields and the multiple points of enhanced symmetry, which are generic features
of moduli space but not usually considered in inflationary model building.
Our scenario predicts cosmic perturbations with an almost exactly flat
spectrum for a wide range of scales with running on smaller, possibly
observable, scales. The running takes the form of either an increasingly steep
drop off of the spectrum, or a rise to a bump in the spectrum before an
increasingly steep drop off.
|
[
{
"created": "Wed, 19 Nov 2003 12:34:09 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Nov 2003 03:48:29 GMT",
"version": "v2"
},
{
"created": "Sat, 22 Nov 2003 08:49:18 GMT",
"version": "v3"
},
{
"created": "Thu, 4 Dec 2003 13:40:50 GMT",
"version": "v4"
}
] |
2009-11-10
|
[
[
"Kadota",
"Kenji",
""
],
[
"Stewart",
"Ewan D.",
""
]
] |
We show that a moduli space of the form predicted by string theory, lifted by supersymmetry breaking, gives rise to successful inflation for large regions of parameter space without any modification or fine tuning. This natural realization of inflation relies crucially on the complex nature of the moduli fields and the multiple points of enhanced symmetry, which are generic features of moduli space but not usually considered in inflationary model building. Our scenario predicts cosmic perturbations with an almost exactly flat spectrum for a wide range of scales with running on smaller, possibly observable, scales. The running takes the form of either an increasingly steep drop off of the spectrum, or a rise to a bump in the spectrum before an increasingly steep drop off.
|
1803.08062
|
Manuel A. Buen-Abad
|
Manuel A. Buen-Abad, Razieh Emami, Martin Schmaltz
|
Cannibal Dark Matter and Large Scale Structure
|
25 pages, 1 appendix. v2: typos corrected, added references
|
Phys. Rev. D 98, 083517 (2018)
|
10.1103/PhysRevD.98.083517
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Cannibals are dark matter particles with a scattering process that allows
three particles to annihilate to two. This exothermic process keeps the gas of
the remaining particles warm long after they become non-relativistic. A
cannibalizing dark sector which is decoupled from the Standard Model naturally
arises from a pure-glue confining hidden sector. It has an effective field
theory description with a single massive interacting real scalar field, the
lightest glueball. Since warm dark matter strongly suppresses growth of
structure cannibals cannot be all of the dark matter. Thus we propose a
scenario where most dark matter is non-interacting and cold but about 1 percent
is cannibalistic. We review the cannibals' unusual scaling of the temperature
and energy and number densities with redshift and generalize the equations for
the growth of matter density perturbations to the case of cannibals. We solve
the equations numerically to predict the scaling of the Hubble parameter and
the characteristic shape of the linear matter power spectrum as a function of
model parameters. Our results may have implications for the $\sigma_8$ and
$H_0$ problems.
|
[
{
"created": "Wed, 21 Mar 2018 18:00:27 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Jul 2018 18:00:00 GMT",
"version": "v2"
}
] |
2018-10-17
|
[
[
"Buen-Abad",
"Manuel A.",
""
],
[
"Emami",
"Razieh",
""
],
[
"Schmaltz",
"Martin",
""
]
] |
Cannibals are dark matter particles with a scattering process that allows three particles to annihilate to two. This exothermic process keeps the gas of the remaining particles warm long after they become non-relativistic. A cannibalizing dark sector which is decoupled from the Standard Model naturally arises from a pure-glue confining hidden sector. It has an effective field theory description with a single massive interacting real scalar field, the lightest glueball. Since warm dark matter strongly suppresses growth of structure cannibals cannot be all of the dark matter. Thus we propose a scenario where most dark matter is non-interacting and cold but about 1 percent is cannibalistic. We review the cannibals' unusual scaling of the temperature and energy and number densities with redshift and generalize the equations for the growth of matter density perturbations to the case of cannibals. We solve the equations numerically to predict the scaling of the Hubble parameter and the characteristic shape of the linear matter power spectrum as a function of model parameters. Our results may have implications for the $\sigma_8$ and $H_0$ problems.
|
hep-ph/0211426
|
Robert Appleby
|
R.B. Appleby and M.H. Seymour
|
Non-global logarithms in inter-jet energy flow with kt clustering
requirement
|
13 pages, 4 figures
|
JHEP 0212 (2002) 063
|
10.1088/1126-6708/2002/12/063
|
MC-TH-2002-11
|
hep-ph
| null |
Recent work in inter-jet energy flow has identified a class of leading
logarithms previously not considered in the literature. These so-called
non-global logarithms have been shown to have significant numerical impact on
gaps-between-jets calculations at the energies of current particle colliders.
Here we calculate, at fixed order and to all orders, the effect of applying
clustering to the gluonic final state responsible for these logarithms for a
trivial colour flow 2 jet system. Such a clustering algorithm has already been
used for experimental measurements at HERA. We find that the impact of the
non-global logarithms is reduced, but not removed, when clustering is demanded,
a result which is of considerable interest for energy flow observable
calculations.
|
[
{
"created": "Wed, 27 Nov 2002 10:16:51 GMT",
"version": "v1"
}
] |
2009-11-07
|
[
[
"Appleby",
"R. B.",
""
],
[
"Seymour",
"M. H.",
""
]
] |
Recent work in inter-jet energy flow has identified a class of leading logarithms previously not considered in the literature. These so-called non-global logarithms have been shown to have significant numerical impact on gaps-between-jets calculations at the energies of current particle colliders. Here we calculate, at fixed order and to all orders, the effect of applying clustering to the gluonic final state responsible for these logarithms for a trivial colour flow 2 jet system. Such a clustering algorithm has already been used for experimental measurements at HERA. We find that the impact of the non-global logarithms is reduced, but not removed, when clustering is demanded, a result which is of considerable interest for energy flow observable calculations.
|
hep-ph/0605208
|
Manuel Donaire
|
M Donaire (DAMTP-Cambridge U.)
|
Topological Defects from First Order Gauge Theory Phase Transitions
|
Corrections made on sections 4,5. Higher quality figures in published
version
|
J.Phys. A39 (2006) 15013-15056
|
10.1088/0305-4470/39/48/012
|
DAMTP-2006-11
|
hep-ph cond-mat.supr-con hep-th
| null |
We investigate the mechanism by which topological defects form in first order
phase transitions with a charged order parameter. We show how thick
superconductor vortices and heavy cosmic strings form by trapping of magnetic
flux. In an external magnetic field, intermediate objects such as strips and
membranes of magnetic flux and chains of single winding defects are produced.
At non-zero temperature, a variety of spontaneous defects of different winding
numbers arise. In cosmology, our results mean that the magnetic flux thermal
fluctuations get trapped in a primordial multi-tension string network. The
mechanism may also apply to the production of cosmic-like strings in brane
collisions. In a thin type-I superconductor film, flux strips are found to be
meta-stable while thick vortices are stable up to some critical value of the
winding number which increases with the thickness of the film. In addition, a
non-dissipative Josephson-like current is obtained across the strips of
quantized magnetic flux.
|
[
{
"created": "Thu, 18 May 2006 21:50:31 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Nov 2006 19:37:32 GMT",
"version": "v2"
}
] |
2009-11-11
|
[
[
"Donaire",
"M",
"",
"DAMTP-Cambridge U."
]
] |
We investigate the mechanism by which topological defects form in first order phase transitions with a charged order parameter. We show how thick superconductor vortices and heavy cosmic strings form by trapping of magnetic flux. In an external magnetic field, intermediate objects such as strips and membranes of magnetic flux and chains of single winding defects are produced. At non-zero temperature, a variety of spontaneous defects of different winding numbers arise. In cosmology, our results mean that the magnetic flux thermal fluctuations get trapped in a primordial multi-tension string network. The mechanism may also apply to the production of cosmic-like strings in brane collisions. In a thin type-I superconductor film, flux strips are found to be meta-stable while thick vortices are stable up to some critical value of the winding number which increases with the thickness of the film. In addition, a non-dissipative Josephson-like current is obtained across the strips of quantized magnetic flux.
|
hep-ph/0504148
|
Lianyi He
|
Lianyi He, Meng Jin and Pengfei Zhuang
|
Neutral Color Superconductivity and Pseudo-Goldstone Modes
|
5 pages, 2 figure
| null | null | null |
hep-ph nucl-th
| null |
Four of the five expected Goldstone modes, which will be eaten up by gauge
fields, in neutral two-flavor color superconductor are actually
pseudo-Goldstone modes, and their degenerated mass is exactly the magnitude of
the color chemical potential, which is introduced to guarantee the color
neutrality at moderate baryon density.
|
[
{
"created": "Mon, 18 Apr 2005 09:26:23 GMT",
"version": "v1"
},
{
"created": "Sun, 24 Apr 2005 08:34:34 GMT",
"version": "v2"
},
{
"created": "Mon, 9 May 2005 09:00:08 GMT",
"version": "v3"
}
] |
2007-05-23
|
[
[
"He",
"Lianyi",
""
],
[
"Jin",
"Meng",
""
],
[
"Zhuang",
"Pengfei",
""
]
] |
Four of the five expected Goldstone modes, which will be eaten up by gauge fields, in neutral two-flavor color superconductor are actually pseudo-Goldstone modes, and their degenerated mass is exactly the magnitude of the color chemical potential, which is introduced to guarantee the color neutrality at moderate baryon density.
|
2303.10507
|
William Saenz-Arevalo
|
G. Ban, J. Chen, P.-J. Chiu, B. Cl\'ement, M. Guigue, T. Jenke, P.
Larue, T. Lefort, O. Naviliat-Cuncic, B. Perriolat, G. Pignol, S. Roccia, W.
Saenz-Arevalo, P. Schmidt-Wellenburg
|
A search for neutron-to-hidden-neutron oscillations in a ultra-cold
neutron beam
| null | null |
10.1103/PhysRevLett.131.191801
| null |
hep-ph
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
Models that postulate the existence of hidden sectors address contemporary
questions, such as the source of baryogenesis and the nature of dark matter.
Among the possible mixing processes, neutron-to-hidden-neutron oscillations
have been repeatedly tested with ultra-cold neutron storage and
passing-through-wall experiments in the range of small ($\delta m<2$ peV) and
large mass splitting ($\delta m>10$ neV), respectively. In this work, we
present a new constraint in the oscillation parameter space derived from
neutron disappearance in ultra-cold neutron beam experiments. The overall
limit, which covers the intermediate mass-splitting range, is given by
$\tau_{nn'}> 1$ s for $|\delta m| \in [2,69]$ peV (95\% C.L.).
|
[
{
"created": "Sat, 18 Mar 2023 21:58:05 GMT",
"version": "v1"
}
] |
2023-11-14
|
[
[
"Ban",
"G.",
""
],
[
"Chen",
"J.",
""
],
[
"Chiu",
"P. -J.",
""
],
[
"Clément",
"B.",
""
],
[
"Guigue",
"M.",
""
],
[
"Jenke",
"T.",
""
],
[
"Larue",
"P.",
""
],
[
"Lefort",
"T.",
""
],
[
"Naviliat-Cuncic",
"O.",
""
],
[
"Perriolat",
"B.",
""
],
[
"Pignol",
"G.",
""
],
[
"Roccia",
"S.",
""
],
[
"Saenz-Arevalo",
"W.",
""
],
[
"Schmidt-Wellenburg",
"P.",
""
]
] |
Models that postulate the existence of hidden sectors address contemporary questions, such as the source of baryogenesis and the nature of dark matter. Among the possible mixing processes, neutron-to-hidden-neutron oscillations have been repeatedly tested with ultra-cold neutron storage and passing-through-wall experiments in the range of small ($\delta m<2$ peV) and large mass splitting ($\delta m>10$ neV), respectively. In this work, we present a new constraint in the oscillation parameter space derived from neutron disappearance in ultra-cold neutron beam experiments. The overall limit, which covers the intermediate mass-splitting range, is given by $\tau_{nn'}> 1$ s for $|\delta m| \in [2,69]$ peV (95\% C.L.).
|
2006.04982
|
Wayne De Paula
|
Orlando Oliveira, Tobias Frederico and Wayne de Paula
|
The soft-gluon limit and the infrared enhancement of the quark-gluon
vertex
| null |
Eur. Phys. J. C (2020) 80: 484
|
10.1140/epjc/s10052-020-8037-0
| null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The Schwinger-Dyson quark equation (SDE) combined with results from lattice
simulation for the propagators are used to obtain information on the
quark-gluon vertex, taking into account the recent full QCD lattice results for
the soft-gluon limit. Its inclusion leads to a clear enhancement of the
infrared quark-gluon vertex. We also find that the relative contribution of the
quark-ghost kernel to the quark-gluon vertex in the infrared region does not
follow the rules from the perturbative analysis of the ultraviolet region. This
shows that for QCD the intuition based on perturbation theory does not apply to
the full momentum range. The framework developed in the current work provides
analytical expressions for all the longitudinal components of vertex taken into
account.
|
[
{
"created": "Mon, 8 Jun 2020 23:05:58 GMT",
"version": "v1"
}
] |
2020-06-11
|
[
[
"Oliveira",
"Orlando",
""
],
[
"Frederico",
"Tobias",
""
],
[
"de Paula",
"Wayne",
""
]
] |
The Schwinger-Dyson quark equation (SDE) combined with results from lattice simulation for the propagators are used to obtain information on the quark-gluon vertex, taking into account the recent full QCD lattice results for the soft-gluon limit. Its inclusion leads to a clear enhancement of the infrared quark-gluon vertex. We also find that the relative contribution of the quark-ghost kernel to the quark-gluon vertex in the infrared region does not follow the rules from the perturbative analysis of the ultraviolet region. This shows that for QCD the intuition based on perturbation theory does not apply to the full momentum range. The framework developed in the current work provides analytical expressions for all the longitudinal components of vertex taken into account.
|
hep-ph/0611376
|
Dani\"el Boer
|
Daniel Boer
|
Gluon saturation effects on single spin asymmetries
|
4 pages, 3 figures, talk presented at the 17th International Spin
Physics Symposium, SPIN2006, Kyoto, Japan, October 2-7, 2006
|
AIPConf.Proc.915:638-641
|
10.1063/1.2750861
| null |
hep-ph
| null |
We consider forward pion production in p p collisions at RHIC energies,which
probes the so-called Extended Geometric Scaling region. Upon inclusion of
small-x effects via an anomalous dimension within the Color Glass Condensate
formalism at leading order in alpha_s, a good description of the cross section
as a function of the transverse momentum of the produced pion is obtained. The
latter is essential for extractions of the Sivers effect from polarized p p
collisions, since it is a sensitive probe of the slope of the cross section.
Hence, the presented approach is well suited to extract the Sivers effect from
single spin asymmetries in forward pion production at high energies.
|
[
{
"created": "Wed, 29 Nov 2006 17:56:21 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Boer",
"Daniel",
""
]
] |
We consider forward pion production in p p collisions at RHIC energies,which probes the so-called Extended Geometric Scaling region. Upon inclusion of small-x effects via an anomalous dimension within the Color Glass Condensate formalism at leading order in alpha_s, a good description of the cross section as a function of the transverse momentum of the produced pion is obtained. The latter is essential for extractions of the Sivers effect from polarized p p collisions, since it is a sensitive probe of the slope of the cross section. Hence, the presented approach is well suited to extract the Sivers effect from single spin asymmetries in forward pion production at high energies.
|
1609.09125
|
Nidal Chamoun
|
E. I. Lashin (Ain Shams U., Cairo and Zewail City Sci. Technol.,
Giza), N. Chamoun (HIAST and Bonn U.), C. Hamzaoui (Quebec U., Montreal), S.
Nasri (United Arab Emirates U.)
|
Rotated $\mu$\,--\,$\tau$ Symmetry for One Generic Neutrino Mixing
Angle: An analytical Study
|
30 pages, version to appear in PRD
|
Phys. Rev. D 96, 015003 (2017)
|
10.1103/PhysRevD.96.015003
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We find a realization of the $Z_2$-symmetry in the neutrino mass matrix which
expresses a rotation of the $\mu-\tau$ symmetry and is able to impose a generic
smallest mixing angle, in contrast to a zero-value predicted by the usual
non-rotated form of the $\mu-\tau$ symmetry. We extend this symmetry for the
lepton sector within type-I seesaw scenario, and show it can accommodate the
mixing angles, the mass hierarchies and the lepton asymmetry in the universe.
We then study the effects of perturbing the specific form of the neutrino mass
matrix imposed by the symmetry and compute the resulting mixing and mass
spectrum. We trace back this "low-scale" perturbation to a "high-scale"
perturbation, and find realizations of this latter one arising from exact
symmetries with an enriched matter content.
|
[
{
"created": "Wed, 28 Sep 2016 21:39:53 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Mar 2017 00:29:57 GMT",
"version": "v2"
},
{
"created": "Fri, 30 Jun 2017 02:24:38 GMT",
"version": "v3"
}
] |
2017-07-12
|
[
[
"Lashin",
"E. I.",
"",
"Ain Shams U., Cairo and Zewail City Sci. Technol.,\n Giza"
],
[
"Chamoun",
"N.",
"",
"HIAST and Bonn U."
],
[
"Hamzaoui",
"C.",
"",
"Quebec U., Montreal"
],
[
"Nasri",
"S.",
"",
"United Arab Emirates U."
]
] |
We find a realization of the $Z_2$-symmetry in the neutrino mass matrix which expresses a rotation of the $\mu-\tau$ symmetry and is able to impose a generic smallest mixing angle, in contrast to a zero-value predicted by the usual non-rotated form of the $\mu-\tau$ symmetry. We extend this symmetry for the lepton sector within type-I seesaw scenario, and show it can accommodate the mixing angles, the mass hierarchies and the lepton asymmetry in the universe. We then study the effects of perturbing the specific form of the neutrino mass matrix imposed by the symmetry and compute the resulting mixing and mass spectrum. We trace back this "low-scale" perturbation to a "high-scale" perturbation, and find realizations of this latter one arising from exact symmetries with an enriched matter content.
|
1310.7856
|
Antonino Di Piazza
|
A. Di Piazza
|
Ultrarelativistic electron states in a general background
electromagnetic field
|
7 pages, 1 figure
|
Phys. Rev. Lett. vol. 113, 040402 (2014)
|
10.1103/PhysRevLett.113.040402
| null |
hep-ph quant-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The feasibility of obtaining exact analytical results in the realm of QED in
the presence of a background electromagnetic field is almost exclusively
limited to a few tractable cases, where the Dirac equation in the corresponding
background field can be solved analytically. This circumstance has restricted,
in particular, the theoretical analysis of QED processes in intense laser
fields to within the plane-wave approximation even at those high intensities,
achievable experimentally only by tightly focusing the laser energy in space.
Here, within the Wentzel-Kramers-Brillouin (WKB) or eikonal approximation, we
construct analytically single-particle electron states in the presence of a
background electromagnetic field of general space-time structure in the
realistic assumption that the initial energy of the electron is the largest
dynamical energy scale in the problem. The relatively compact expression of
these states opens, in particular, the possibility of investigating
analytically strong-field QED processes in the presence of spatially focused
laser beams, which is of particular relevance in view of the upcoming
experimental campaigns in this field.
|
[
{
"created": "Tue, 29 Oct 2013 16:08:19 GMT",
"version": "v1"
},
{
"created": "Sun, 27 Jul 2014 10:15:06 GMT",
"version": "v2"
}
] |
2016-05-04
|
[
[
"Di Piazza",
"A.",
""
]
] |
The feasibility of obtaining exact analytical results in the realm of QED in the presence of a background electromagnetic field is almost exclusively limited to a few tractable cases, where the Dirac equation in the corresponding background field can be solved analytically. This circumstance has restricted, in particular, the theoretical analysis of QED processes in intense laser fields to within the plane-wave approximation even at those high intensities, achievable experimentally only by tightly focusing the laser energy in space. Here, within the Wentzel-Kramers-Brillouin (WKB) or eikonal approximation, we construct analytically single-particle electron states in the presence of a background electromagnetic field of general space-time structure in the realistic assumption that the initial energy of the electron is the largest dynamical energy scale in the problem. The relatively compact expression of these states opens, in particular, the possibility of investigating analytically strong-field QED processes in the presence of spatially focused laser beams, which is of particular relevance in view of the upcoming experimental campaigns in this field.
|
1002.0566
|
Claude Roiesnel
|
Cyrille Marquet, Claude Roiesnel and Samuel Wallon
|
Virtual Compton Scattering off a Spinless Target in AdS/QCD
|
21 pages, version to be published in JHEP.
|
JHEP 1004:051,2010
|
10.1007/JHEP04(2010)051
| null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the doubly virtual Compton scattering off a spinless target
$\gamma^*P\to\gamma^*P'$ within the Anti-de Sitter(AdS)/QCD formalism. We find
that the general structure allowed by the Lorentz invariance and gauge
invariance of the Compton amplitude is not easily reproduced with the standard
recipes of the AdS/QCD correspondence. In the soft-photon regime, where the
semi-classical approximation is supposed to apply best, we show that the
measurements of the electric and magnetic polarizabilities of a target like the
charged pion in real Compton scattering, can already serve as stringent tests.
|
[
{
"created": "Tue, 2 Feb 2010 19:22:31 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Apr 2010 15:01:33 GMT",
"version": "v2"
}
] |
2014-11-20
|
[
[
"Marquet",
"Cyrille",
""
],
[
"Roiesnel",
"Claude",
""
],
[
"Wallon",
"Samuel",
""
]
] |
We study the doubly virtual Compton scattering off a spinless target $\gamma^*P\to\gamma^*P'$ within the Anti-de Sitter(AdS)/QCD formalism. We find that the general structure allowed by the Lorentz invariance and gauge invariance of the Compton amplitude is not easily reproduced with the standard recipes of the AdS/QCD correspondence. In the soft-photon regime, where the semi-classical approximation is supposed to apply best, we show that the measurements of the electric and magnetic polarizabilities of a target like the charged pion in real Compton scattering, can already serve as stringent tests.
|
hep-ph/0102071
|
Daniel Boer
|
Daniel Boer (RIKEN-BNL Research Center)
|
Sudakov suppression in azimuthal spin asymmetries
|
17 pages, Revtex, 6 Postscript figures, uses aps.sty, epsf.sty;
Section II partly rewritten, Figure 4 replaced, some minor other changes
|
Nucl.Phys. B603 (2001) 195-217
|
10.1016/S0550-3213(01)00156-0
| null |
hep-ph
| null |
It is shown that transverse momentum dependent azimuthal spin asymmetries
suffer from suppression due to Sudakov factors, in the region where the
transverse momentum is much smaller than the large energy scale Q^2. The size
and Q^2 dependence of this suppression are studied numerically for two such
asymmetries, both arising due to the Collins effect. General features are
discussed of how the fall-off with Q^2 is affected by the nonperturbative
Sudakov factor and by the transverse momentum weights and angular dependences
that appear in different asymmetries. For a subset of asymmetries the
asymptotic Q^2 behavior is calculated analytically, providing an upper bound
for the decrease with energy of other asymmetries. The effect of Sudakov
factors on the transverse momentum distributions is found to be very
significant already at present-day collider energies. Therefore, it is
essential to take into account Sudakov factors in transverse momentum dependent
azimuthal spin asymmetries.
|
[
{
"created": "Tue, 6 Feb 2001 22:09:49 GMT",
"version": "v1"
},
{
"created": "Fri, 25 May 2001 20:23:43 GMT",
"version": "v2"
}
] |
2009-11-07
|
[
[
"Boer",
"Daniel",
"",
"RIKEN-BNL Research Center"
]
] |
It is shown that transverse momentum dependent azimuthal spin asymmetries suffer from suppression due to Sudakov factors, in the region where the transverse momentum is much smaller than the large energy scale Q^2. The size and Q^2 dependence of this suppression are studied numerically for two such asymmetries, both arising due to the Collins effect. General features are discussed of how the fall-off with Q^2 is affected by the nonperturbative Sudakov factor and by the transverse momentum weights and angular dependences that appear in different asymmetries. For a subset of asymmetries the asymptotic Q^2 behavior is calculated analytically, providing an upper bound for the decrease with energy of other asymmetries. The effect of Sudakov factors on the transverse momentum distributions is found to be very significant already at present-day collider energies. Therefore, it is essential to take into account Sudakov factors in transverse momentum dependent azimuthal spin asymmetries.
|
1406.7782
|
Eliecer Hern\'andez Gajate
|
C. Albertus, E. Hern\'andez and J. Nieves
|
$B\to \rho$ semileptonic decays and $|V_{ub}|$
|
13 latex pages, 3 figures, 3 tables. We have corrected a
misinterpretation of experimental data on partial branching fractions.
Results are modified but main conclusion remains the same
|
Physical Review D 90, 013017 (2014); erratum Physical Review D 90,
079906 (2014)
|
10.1103/PhysRevD.90.013017
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We reevaluate the $B\to\rho\,l^+\nu_l$ decay width as a full
$B\to\pi\pi\,l^+\nu_l$ four-particle decay, in which the two final pions are
produced via an intermediate $\rho$ meson. The decay width can be written as a
convolution of the $B\to\rho\,l^+\nu_l$ decay width, for an off-shell $\rho$,
with the $\rho\to\pi\pi$ line shape. This allows to fully incorporate the
effects of the finite $\rho$ meson width. As shown, consideration of the $\rho$
meson width effects increase the $|V_{ub}|$ value by some 8%, rendering it in
better agreement with the determination based in the $B\to\pi$ decay. We take
the $q^2$ dependence of the $B\to \rho$ semileptonic form factors from a
dispersive Omn\`es representation. The Omn\`es subtraction constants and the
overall normalization parameter $|V_{ub}|$ are fitted to light cone sum rules
and lattice QCD theoretical form-factor calculations, in the low and high $q^2$
regions respectively, together to the CLEO, BaBar and Belle experimental
partial branching fraction distributions. The extracted value from this global
fit is $|V_{ub}|=(3.12\pm 0.13)\times 10^{-3}$, in agreement with the average
$B\to \pi$ exclusive value $|V_{ub}|=(3.23\pm 0.31)\times 10^{-3}$ quoted by
the Particle Data Group. The extracted value increases to $|V_{ub}|=(3.51\pm
0.16)\times 10^{-3}$ if only the most recent Belle Collaboration data is used.
This latter value is in agreement with different theoretical determinations
based in the $B\to\pi$ semileptonic decay and the values obtained by the
CKMfitter and UTfit groups. In any case a clear tension with the $|V_{ub}|$
value extracted from inclusive semileptonic $b\to u$ decays still persists.
|
[
{
"created": "Mon, 30 Jun 2014 15:52:29 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Nov 2014 08:14:56 GMT",
"version": "v2"
}
] |
2015-06-22
|
[
[
"Albertus",
"C.",
""
],
[
"Hernández",
"E.",
""
],
[
"Nieves",
"J.",
""
]
] |
We reevaluate the $B\to\rho\,l^+\nu_l$ decay width as a full $B\to\pi\pi\,l^+\nu_l$ four-particle decay, in which the two final pions are produced via an intermediate $\rho$ meson. The decay width can be written as a convolution of the $B\to\rho\,l^+\nu_l$ decay width, for an off-shell $\rho$, with the $\rho\to\pi\pi$ line shape. This allows to fully incorporate the effects of the finite $\rho$ meson width. As shown, consideration of the $\rho$ meson width effects increase the $|V_{ub}|$ value by some 8%, rendering it in better agreement with the determination based in the $B\to\pi$ decay. We take the $q^2$ dependence of the $B\to \rho$ semileptonic form factors from a dispersive Omn\`es representation. The Omn\`es subtraction constants and the overall normalization parameter $|V_{ub}|$ are fitted to light cone sum rules and lattice QCD theoretical form-factor calculations, in the low and high $q^2$ regions respectively, together to the CLEO, BaBar and Belle experimental partial branching fraction distributions. The extracted value from this global fit is $|V_{ub}|=(3.12\pm 0.13)\times 10^{-3}$, in agreement with the average $B\to \pi$ exclusive value $|V_{ub}|=(3.23\pm 0.31)\times 10^{-3}$ quoted by the Particle Data Group. The extracted value increases to $|V_{ub}|=(3.51\pm 0.16)\times 10^{-3}$ if only the most recent Belle Collaboration data is used. This latter value is in agreement with different theoretical determinations based in the $B\to\pi$ semileptonic decay and the values obtained by the CKMfitter and UTfit groups. In any case a clear tension with the $|V_{ub}|$ value extracted from inclusive semileptonic $b\to u$ decays still persists.
|
1912.08641
|
Gabriel Koole
|
Robert Fleischer, Ruben Jaarsma, Gabri\"el Koole
|
Testing Lepton Flavour Universality with (Semi)-Leptonic $D_{(s)}$
Decays
|
34 pages, 17 figures. v2: references added
| null |
10.1140/epjc/s10052-020-7702-7
|
Nikhef-2019-056, MPP-2019-252
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Data in $B$-meson decays indicate violations of lepton flavour universality,
thereby raising the question about such phenomena in the charm sector. We
perform a model-independent analysis of NP contributions in (semi)-leptonic
decays of $D_{(s)}$ mesons which originate from $c \to d \bar{\ell} \nu_{\ell}$
and $c \to s \bar{\ell} \nu_{\ell}$ charge-current interactions. Starting from
the most general low-energy effective Hamiltonian containing four-fermion
operators and the corresponding short-distance coefficients, we explore the
impact of new (pseudo)-scalar, vector and tensor operators and constrain their
effects through the interplay with current data. We pay special attention to
the elements $|V_{cd}|$ and $|V_{cs}|$ of the Cabibbo--Kobayashi--Maskawa
matrix and extract them from the $D_{(s)}$ decays in the presence of possible
NP decay contributions, comparing them with determinations utilizing unitarity.
We find a picture in agreement with the Standard Model within the current
uncertainties. Using the results from our analysis, we make also predictions
for leptonic $D_{(s)}^+ \to e^+ \nu_e$ modes which could be hugely enhanced
with respect to their tiny Standard Model branching ratios. It will be
interesting to apply our strategy at the future high-precision frontier.
|
[
{
"created": "Wed, 18 Dec 2019 14:45:58 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Dec 2019 18:15:32 GMT",
"version": "v2"
}
] |
2020-03-18
|
[
[
"Fleischer",
"Robert",
""
],
[
"Jaarsma",
"Ruben",
""
],
[
"Koole",
"Gabriël",
""
]
] |
Data in $B$-meson decays indicate violations of lepton flavour universality, thereby raising the question about such phenomena in the charm sector. We perform a model-independent analysis of NP contributions in (semi)-leptonic decays of $D_{(s)}$ mesons which originate from $c \to d \bar{\ell} \nu_{\ell}$ and $c \to s \bar{\ell} \nu_{\ell}$ charge-current interactions. Starting from the most general low-energy effective Hamiltonian containing four-fermion operators and the corresponding short-distance coefficients, we explore the impact of new (pseudo)-scalar, vector and tensor operators and constrain their effects through the interplay with current data. We pay special attention to the elements $|V_{cd}|$ and $|V_{cs}|$ of the Cabibbo--Kobayashi--Maskawa matrix and extract them from the $D_{(s)}$ decays in the presence of possible NP decay contributions, comparing them with determinations utilizing unitarity. We find a picture in agreement with the Standard Model within the current uncertainties. Using the results from our analysis, we make also predictions for leptonic $D_{(s)}^+ \to e^+ \nu_e$ modes which could be hugely enhanced with respect to their tiny Standard Model branching ratios. It will be interesting to apply our strategy at the future high-precision frontier.
|
1005.4001
|
Nello Paver
|
N. Paver and Riazuddin
|
On meson dominance in the `second class' tau \to eta pi nu_tau decay
|
8 pages
|
Phys.Rev.D82:057301,2010
|
10.1103/PhysRevD.82.057301
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Motivated by recent estimates of the isospin-violating process tau \to eta pi
nu_tau, mostly relying on the rho and a_0 dominance of the relevant form
factors near threshold, we present an assessment for the branching ratio that
accounts for additional, potential, effects from the lowest radial excitations
rho(1450) and a_0(1450), respectively, also lying in the decay phase space.
|
[
{
"created": "Fri, 21 May 2010 16:57:04 GMT",
"version": "v1"
}
] |
2014-11-21
|
[
[
"Paver",
"N.",
""
],
[
"Riazuddin",
"",
""
]
] |
Motivated by recent estimates of the isospin-violating process tau \to eta pi nu_tau, mostly relying on the rho and a_0 dominance of the relevant form factors near threshold, we present an assessment for the branching ratio that accounts for additional, potential, effects from the lowest radial excitations rho(1450) and a_0(1450), respectively, also lying in the decay phase space.
|
2303.07968
|
Xiao-Yun Wang
|
Xiao-Yun Wang, Chen Dong, Quanjin Wang
|
Determination of the distribution of strong coupling constant with
machine learning
|
This work is a very preliminary result of using machine learning to
study strong coupling constants. It is not a very mature work, and there are
still certain uncertainties in the results. In a responsible manner, we
decided to withdraw this manuscript after deliberation, and readers are
invited to pay attention to our follow-up work on strong coupling constants
in machine learning
| null | null | null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
In this work, we use the artificial neural network (ANN) method to study and
predict the distribution of strong coupling constants by fitting the existing
data. Our approach takes advantage of the ability of ANN to learn complex
nonlinear relations and excellent generalization, and allows for a systematic
treatment of the uncertainties associated with the data. To ensure the
reliability of our results, we apply three evaluation indexes to evaluate the
accuracy of model during training. Finally, we obtained the predicted values of
the strong coupling constants at different energy scales, and compared and
verified them with the existing experimental data. Our approach represents a
promising way to improve the determination of the strong coupling constant at
low energies, and could have important implications for future experimental and
theoretical studies in quantum chromodynamics.
|
[
{
"created": "Tue, 14 Mar 2023 15:19:09 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Apr 2023 13:25:17 GMT",
"version": "v2"
},
{
"created": "Fri, 9 Jun 2023 00:05:15 GMT",
"version": "v3"
}
] |
2023-06-12
|
[
[
"Wang",
"Xiao-Yun",
""
],
[
"Dong",
"Chen",
""
],
[
"Wang",
"Quanjin",
""
]
] |
In this work, we use the artificial neural network (ANN) method to study and predict the distribution of strong coupling constants by fitting the existing data. Our approach takes advantage of the ability of ANN to learn complex nonlinear relations and excellent generalization, and allows for a systematic treatment of the uncertainties associated with the data. To ensure the reliability of our results, we apply three evaluation indexes to evaluate the accuracy of model during training. Finally, we obtained the predicted values of the strong coupling constants at different energy scales, and compared and verified them with the existing experimental data. Our approach represents a promising way to improve the determination of the strong coupling constant at low energies, and could have important implications for future experimental and theoretical studies in quantum chromodynamics.
|
1203.6787
|
Grzegorz Wilk
|
Maciej Rybczynski, Zbigniew Wlodarczyk and Grzegorz Wilk
|
On the possibility of q-scaling in high energy production processes
|
Final version, accepted by J.Phys. G
|
J. Phys. G: Nucl. Part. Phys. 39 (2012) 095004
|
10.1088/0954-3899/39/9/095004
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
It has been noticed recently that transverse momenta (p_T) distributions
observed in high energy production processes exhibit remarkably universal
scaling behaviour. This is the case when a suitable variable replaces the usual
p_T. On the other hand, it is also widely known that transverse momentum
distributions in general follow a power-like Tsallis distribution, rather than
an exponential Boltzmann-Gibbs, with a (generally energy dependent)
nonextensivity parameter q. Here we show that it is possible to choose a
suitable variable such that all the data can be fitted by the same Tsallis
distribution (with the same, energy independent value of the q-parameter). Thus
they exhibit q-scaling.
|
[
{
"created": "Fri, 30 Mar 2012 12:29:41 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Jun 2012 14:41:15 GMT",
"version": "v2"
},
{
"created": "Wed, 11 Jul 2012 15:28:44 GMT",
"version": "v3"
}
] |
2015-06-04
|
[
[
"Rybczynski",
"Maciej",
""
],
[
"Wlodarczyk",
"Zbigniew",
""
],
[
"Wilk",
"Grzegorz",
""
]
] |
It has been noticed recently that transverse momenta (p_T) distributions observed in high energy production processes exhibit remarkably universal scaling behaviour. This is the case when a suitable variable replaces the usual p_T. On the other hand, it is also widely known that transverse momentum distributions in general follow a power-like Tsallis distribution, rather than an exponential Boltzmann-Gibbs, with a (generally energy dependent) nonextensivity parameter q. Here we show that it is possible to choose a suitable variable such that all the data can be fitted by the same Tsallis distribution (with the same, energy independent value of the q-parameter). Thus they exhibit q-scaling.
|
hep-ph/0408216
|
Nestor Armesto
|
J. L. Albacete, N. Armesto, J. G. Milhano, C. A. Salgado and U. A.
Wiedemann
|
Numerical analysis of the Balitsky-Kovchegov equation with running
coupling: dependence of the saturation scale on nuclear size and rapidity
|
LaTeX, 29 pages, 7 eps figures; discussion on DLL enlarged and
comparison with sub-leading terms in the rapidity behaviour of the saturation
scale added
|
Phys.Rev. D71 (2005) 014003
|
10.1103/PhysRevD.71.014003
|
CERN-PH-TH/2004-157
|
hep-ph
| null |
We study the effects of including a running coupling constant in high-density
QCD evolution. For fixed coupling constant, QCD evolution preserves the initial
dependence of the saturation momentum $Q_s$ on the nuclear size $A$ and results
in an exponential dependence on rapidity $Y$, $Q^2_s(Y) = Q^2_s(Y_0) \exp{[
\bar\alpha_s d (Y-Y_0) ]}$. For the running coupling case, we re-derive
analytical estimates for the $A$- and $Y$-dependences of the saturation scale
and test them numerically. The $A$-dependence of $Q_s$ vanishes $\propto 1/
\sqrt{Y}$ for large $A$ and $Y$. The $Y$-dependence is reduced to $Q_s^2(Y)
\propto \exp{(\Delta^\prime\sqrt{Y+X})}$ where we find numerically
$\Delta^\prime\simeq 3.2$. We study the behaviour of the gluon distribution at
large transverse momentum, characterizing it by an anomalous dimension
$1-\gamma$ which we define in a fixed region of small dipole sizes. In contrast
to previous analytical work, we find a marked difference between the fixed
coupling ($\gamma \simeq 0.65$) and running coupling ($\gamma \sim 0.85$)
results. Our numerical findings show that both a scaling function depending
only on the variable $r Q_s$ and the perturbative double-leading-logarithmic
expression, provide equally good descriptions of the numerical solutions for
very small $r$-values below the so-called scaling window.
|
[
{
"created": "Thu, 19 Aug 2004 17:13:42 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Nov 2004 11:37:33 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Albacete",
"J. L.",
""
],
[
"Armesto",
"N.",
""
],
[
"Milhano",
"J. G.",
""
],
[
"Salgado",
"C. A.",
""
],
[
"Wiedemann",
"U. A.",
""
]
] |
We study the effects of including a running coupling constant in high-density QCD evolution. For fixed coupling constant, QCD evolution preserves the initial dependence of the saturation momentum $Q_s$ on the nuclear size $A$ and results in an exponential dependence on rapidity $Y$, $Q^2_s(Y) = Q^2_s(Y_0) \exp{[ \bar\alpha_s d (Y-Y_0) ]}$. For the running coupling case, we re-derive analytical estimates for the $A$- and $Y$-dependences of the saturation scale and test them numerically. The $A$-dependence of $Q_s$ vanishes $\propto 1/ \sqrt{Y}$ for large $A$ and $Y$. The $Y$-dependence is reduced to $Q_s^2(Y) \propto \exp{(\Delta^\prime\sqrt{Y+X})}$ where we find numerically $\Delta^\prime\simeq 3.2$. We study the behaviour of the gluon distribution at large transverse momentum, characterizing it by an anomalous dimension $1-\gamma$ which we define in a fixed region of small dipole sizes. In contrast to previous analytical work, we find a marked difference between the fixed coupling ($\gamma \simeq 0.65$) and running coupling ($\gamma \sim 0.85$) results. Our numerical findings show that both a scaling function depending only on the variable $r Q_s$ and the perturbative double-leading-logarithmic expression, provide equally good descriptions of the numerical solutions for very small $r$-values below the so-called scaling window.
|
hep-ph/0005078
|
Daniele Treleani
|
Mikhail Braun, Daniele Treleani
|
The double parton distributions in the hard pomeron model
|
29 pages, 6 figures
|
Eur.Phys.J.C18:511-522,2001
|
10.1007/s100520100565
| null |
hep-ph
| null |
We study the double parton interaction process in collisions between highly
virtual $q{\bar q}$ pairs in the BFKL regime. Explicit expressions for the
double parton distributions are obtained both in the case of direct coupling of
the BFKL pomerons to the $q{\bar q}$ pair and in the case of triple pomeron
interaction.
|
[
{
"created": "Tue, 9 May 2000 11:32:18 GMT",
"version": "v1"
}
] |
2009-01-07
|
[
[
"Braun",
"Mikhail",
""
],
[
"Treleani",
"Daniele",
""
]
] |
We study the double parton interaction process in collisions between highly virtual $q{\bar q}$ pairs in the BFKL regime. Explicit expressions for the double parton distributions are obtained both in the case of direct coupling of the BFKL pomerons to the $q{\bar q}$ pair and in the case of triple pomeron interaction.
|
1404.4230
|
Jun Song
|
Jun Song and Feng-lan Shao
|
Probing charge correlations of quark gluon plasma by identified
two-hadron rapidity correlations in ultra-relativistic AA collisions
|
4 pages, 1 figure
| null | null | null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We propose a new kind of two-particle correlation of identified hadrons in
longitudinal rapidity space, called $G_{\alpha\beta}(y_{\alpha},y_{\beta})$,
which can reflect clearly the charge correlations of hot quark system produced
in AA collisions at LHC energies. It is derived from the basic scenario of
quark combination mechanism of hadron production. Like the elliptic flow of
identified hadrons at intermediate transverse momentum, this correlation is
independent of the absolute hadronic yields but dependent only on the flavor
compositions of hadrons, and thus exhibits interesting properties for different
kinds of hadron species. We suggest the measurement of this observable in AA
collisions at LHC to gain more insights into the charge correlation properties
of produced hot quark matter.
|
[
{
"created": "Wed, 16 Apr 2014 13:05:53 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Apr 2014 16:19:06 GMT",
"version": "v2"
}
] |
2014-04-22
|
[
[
"Song",
"Jun",
""
],
[
"Shao",
"Feng-lan",
""
]
] |
We propose a new kind of two-particle correlation of identified hadrons in longitudinal rapidity space, called $G_{\alpha\beta}(y_{\alpha},y_{\beta})$, which can reflect clearly the charge correlations of hot quark system produced in AA collisions at LHC energies. It is derived from the basic scenario of quark combination mechanism of hadron production. Like the elliptic flow of identified hadrons at intermediate transverse momentum, this correlation is independent of the absolute hadronic yields but dependent only on the flavor compositions of hadrons, and thus exhibits interesting properties for different kinds of hadron species. We suggest the measurement of this observable in AA collisions at LHC to gain more insights into the charge correlation properties of produced hot quark matter.
|
1710.01971
|
Kazem Azizi
|
S. S. Agaev, K. Azizi, H. Sundu
|
Testing the doubly charged charm-strange tetraquarks
|
14 Pages, 4 Figures and 3 Tables. To be published in EPJC
| null |
10.1140/epjc/s10052-018-5640-4
| null |
hep-ph hep-ex hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The spectroscopic parameters and decay channels of the doubly charged scalar,
pseudoscalar and axial-vector charm-strange tetraquarks $Z_{
\overline{c}s}=[sd][\overline u \overline c]$ are explored within framework of
the QCD sum rule. The masses and current couplings of these diquark-antidiquark
states are calculated by means of two-point correlation functions and taking
into account the vacuum condensates up to eight dimensions. To compute the
strong couplings of $Z_{\overline{c}s}$ states with $D,\ D_{s},\ D^{\ast},\
D_{s}^{\ast},\ D_{s1}(2460),\ D_{s0}^{\ast}(2317),\ \pi$ and $K$ mesons we use
QCD light-cone sum rules and evaluate width of their $S$- and $P$-wave decays
to a pair of negatively charged conventional mesons: For the scalar state
$Z_{\overline{c}s}\to D_s \pi,\ DK, \ D_{s1}(2460)\pi$, for the pseudoscalar
state $Z_{\overline{c}s} \to D_{s}^{\ast}\pi,\ D^{\ast}K, \
D_{s0}^{\ast}(2317)\pi,$ and for the axial-vector state $Z_{\overline{c}s} \to
D_{s}^{\ast}\pi,\ D^{\ast}K,\ D_{s1}(2460)\pi$ decays are investigated.
Obtained predictions for the spectroscopic parameters and decay widths of the
$Z_{\overline{c}s}$ tetraquarks may be useful for experimental investigations
of the doubly charged exotic hadrons.
|
[
{
"created": "Thu, 5 Oct 2017 11:31:46 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Oct 2017 09:38:43 GMT",
"version": "v2"
},
{
"created": "Mon, 12 Feb 2018 09:08:22 GMT",
"version": "v3"
},
{
"created": "Tue, 13 Feb 2018 07:01:01 GMT",
"version": "v4"
}
] |
2018-04-04
|
[
[
"Agaev",
"S. S.",
""
],
[
"Azizi",
"K.",
""
],
[
"Sundu",
"H.",
""
]
] |
The spectroscopic parameters and decay channels of the doubly charged scalar, pseudoscalar and axial-vector charm-strange tetraquarks $Z_{ \overline{c}s}=[sd][\overline u \overline c]$ are explored within framework of the QCD sum rule. The masses and current couplings of these diquark-antidiquark states are calculated by means of two-point correlation functions and taking into account the vacuum condensates up to eight dimensions. To compute the strong couplings of $Z_{\overline{c}s}$ states with $D,\ D_{s},\ D^{\ast},\ D_{s}^{\ast},\ D_{s1}(2460),\ D_{s0}^{\ast}(2317),\ \pi$ and $K$ mesons we use QCD light-cone sum rules and evaluate width of their $S$- and $P$-wave decays to a pair of negatively charged conventional mesons: For the scalar state $Z_{\overline{c}s}\to D_s \pi,\ DK, \ D_{s1}(2460)\pi$, for the pseudoscalar state $Z_{\overline{c}s} \to D_{s}^{\ast}\pi,\ D^{\ast}K, \ D_{s0}^{\ast}(2317)\pi,$ and for the axial-vector state $Z_{\overline{c}s} \to D_{s}^{\ast}\pi,\ D^{\ast}K,\ D_{s1}(2460)\pi$ decays are investigated. Obtained predictions for the spectroscopic parameters and decay widths of the $Z_{\overline{c}s}$ tetraquarks may be useful for experimental investigations of the doubly charged exotic hadrons.
|
1806.05191
|
Giovanna Cottin
|
Giovanna Cottin, Juan Carlos Helo, Martin Hirsch
|
Displaced vertices as probes of sterile neutrino mixing at the LHC
|
12 pages, 4 figures. v2 includes added references and new Table 1.
Version accepted for publication in PRD
|
Phys. Rev. D 98, 035012 (2018)
|
10.1103/PhysRevD.98.035012
|
IFIC/18-25
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate the reach at the LHC to probe light sterile neutrinos with
displaced vertices. We focus on sterile neutrinos $N$ with masses $m_{N} \sim $
(5-30) GeV, that are produced in rare decays of the Standard Model gauge bosons
and decay inside the inner trackers of the LHC detectors. With a strategy that
triggers on the prompt lepton accompanying the $N$ displaced vertex and
considers charged tracks associated to it, we show that the 13 TeV LHC with
$3000$/fb is able to probe active-sterile neutrino mixings down to
$|V_{lN}|^2\approx 10^{-9}$, with $l=e,\mu$, which is an improvement of up to
four orders of magnitude when comparing with current experimental limits from
trileptons and proposed lepton-jets searches. In the case when $\tau$ mixing is
present, mixing angles as low as $|V_{\tau N}|^2 \approx 10^{-8}$ can be
accessed.
|
[
{
"created": "Wed, 13 Jun 2018 18:00:02 GMT",
"version": "v1"
},
{
"created": "Fri, 3 Aug 2018 14:29:17 GMT",
"version": "v2"
}
] |
2018-08-15
|
[
[
"Cottin",
"Giovanna",
""
],
[
"Helo",
"Juan Carlos",
""
],
[
"Hirsch",
"Martin",
""
]
] |
We investigate the reach at the LHC to probe light sterile neutrinos with displaced vertices. We focus on sterile neutrinos $N$ with masses $m_{N} \sim $ (5-30) GeV, that are produced in rare decays of the Standard Model gauge bosons and decay inside the inner trackers of the LHC detectors. With a strategy that triggers on the prompt lepton accompanying the $N$ displaced vertex and considers charged tracks associated to it, we show that the 13 TeV LHC with $3000$/fb is able to probe active-sterile neutrino mixings down to $|V_{lN}|^2\approx 10^{-9}$, with $l=e,\mu$, which is an improvement of up to four orders of magnitude when comparing with current experimental limits from trileptons and proposed lepton-jets searches. In the case when $\tau$ mixing is present, mixing angles as low as $|V_{\tau N}|^2 \approx 10^{-8}$ can be accessed.
|
1705.00449
|
Yu Lu
|
Yu Lu, Muhammad Naeem Anwar, Bing-Song Zou
|
$X(4260)$ Revisited: A Coupled Channel Perspective
|
10 pages, 1 figure
|
Phys. Rev. D 96, 114022 (2017)
|
10.1103/PhysRevD.96.114022
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We calculate the probabilities of various charmed meson molecules for
$X(4260)$ under the framework of ${}^3P_0$ model. The results indicate that
even though heavy quark spin symmetry forbids $S$ wave coupling of $D_1\bar{D}$
to the ${}^3S_1$ charmonia ($\psi(nS)$), the $D$ wave coupling is allowed and
not negligible. Under this symmetry, the $D_1\bar{D}$ can couple to ${}^3D_1$
charmonia ($\psi(nD)$) via both $S$ and $D$ wave, and the overall coupling is
around three times larger than that of $\psi(nS)$. The $X(4260)$ cannot be a
pure molecule but a mixture of a charmonium and various charmed meson
components. Since the $D_1\bar{D}$ couples strongly to $\psi(nD)$, our results
suggest that in the $D_1\bar{D}$ molecular picture, the charmonium core of
$X(4260)$ is $\psi(nD)$ instead of $\psi(nS)$. As a result, the experimental
fact that the $R$ ratio has a dip around 4.26 GeV can be understood in the
$D_1\bar{D}$ molecular picture of the $X(4260)$.
|
[
{
"created": "Mon, 1 May 2017 09:01:24 GMT",
"version": "v1"
},
{
"created": "Mon, 12 Jun 2017 13:24:00 GMT",
"version": "v2"
},
{
"created": "Thu, 7 Sep 2017 14:20:17 GMT",
"version": "v3"
},
{
"created": "Fri, 22 Dec 2017 15:54:43 GMT",
"version": "v4"
}
] |
2017-12-27
|
[
[
"Lu",
"Yu",
""
],
[
"Anwar",
"Muhammad Naeem",
""
],
[
"Zou",
"Bing-Song",
""
]
] |
We calculate the probabilities of various charmed meson molecules for $X(4260)$ under the framework of ${}^3P_0$ model. The results indicate that even though heavy quark spin symmetry forbids $S$ wave coupling of $D_1\bar{D}$ to the ${}^3S_1$ charmonia ($\psi(nS)$), the $D$ wave coupling is allowed and not negligible. Under this symmetry, the $D_1\bar{D}$ can couple to ${}^3D_1$ charmonia ($\psi(nD)$) via both $S$ and $D$ wave, and the overall coupling is around three times larger than that of $\psi(nS)$. The $X(4260)$ cannot be a pure molecule but a mixture of a charmonium and various charmed meson components. Since the $D_1\bar{D}$ couples strongly to $\psi(nD)$, our results suggest that in the $D_1\bar{D}$ molecular picture, the charmonium core of $X(4260)$ is $\psi(nD)$ instead of $\psi(nS)$. As a result, the experimental fact that the $R$ ratio has a dip around 4.26 GeV can be understood in the $D_1\bar{D}$ molecular picture of the $X(4260)$.
|
hep-ph/0007153
|
Volodymyr Uleshchenko
|
V.Uleshchenko, A.Szczurek, J.Speth
|
Semi-inclusive production of pions in DIS and $\bar d - \bar u$
asymmetry
|
A talk given at the workshop "Meson2000", Cracow, Poland, 19-23 May
2000
|
Acta Phys.Polon. B31 (2000) 2443-2451
| null | null |
hep-ph
| null |
We discuss the role of some nonpartonic effects which lead to $N_p^{\pi^+}
\ne N_n^{\pi^+}$ and $N_p^{\pi^-} \ne N_n^{\pi^-}$ and may therefore modify the
conclusionon the $\bar d - \bar u$ asymmetry extracted from semi-inclusive
production of pions in DIS. Quantitative estimations for resolved photon and
exclusive $\rho^0$ are given as examples. The results are discussed in the
context of recent HERMES data.
|
[
{
"created": "Fri, 14 Jul 2000 13:39:39 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Uleshchenko",
"V.",
""
],
[
"Szczurek",
"A.",
""
],
[
"Speth",
"J.",
""
]
] |
We discuss the role of some nonpartonic effects which lead to $N_p^{\pi^+} \ne N_n^{\pi^+}$ and $N_p^{\pi^-} \ne N_n^{\pi^-}$ and may therefore modify the conclusionon the $\bar d - \bar u$ asymmetry extracted from semi-inclusive production of pions in DIS. Quantitative estimations for resolved photon and exclusive $\rho^0$ are given as examples. The results are discussed in the context of recent HERMES data.
|
1007.5172
|
Jacopo Ghiglieri
|
Nora Brambilla, Jacopo Ghiglieri, Peter Petreczky, Antonio Vairo
|
Polyakov loop and correlator of Polyakov loops at
next-to-next-to-leading order
|
53 pages, 9 figures, version published in PRD
|
Phys.Rev.D82:074019,2010
|
10.1103/PhysRevD.82.074019
|
TUM-EFT 2/09, INT-PUB-10-056
|
hep-ph hep-lat nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the Polyakov loop and the correlator of two Polyakov loops at finite
temperature in the weak-coupling regime. We calculate the Polyakov loop at
order g^4. The calculation of the correlator of two Polyakov loops is performed
at distances shorter than the inverse of the temperature and for electric
screening masses larger than the Coulomb potential. In this regime, it is
accurate up to order g^6. We also evaluate the Polyakov-loop correlator in an
effective field theory framework that takes advantage of the hierarchy of
energy scales in the problem and makes explicit the bound-state dynamics. In
the effective field theory framework, we show that the Polyakov-loop correlator
is at leading order in the multipole expansion the sum of a colour-singlet and
a colour-octet quark-antiquark correlator, which are gauge invariant, and
compute the corresponding colour-singlet and colour-octet free energies.
|
[
{
"created": "Thu, 29 Jul 2010 09:54:19 GMT",
"version": "v1"
},
{
"created": "Mon, 4 Oct 2010 16:05:19 GMT",
"version": "v2"
}
] |
2010-10-27
|
[
[
"Brambilla",
"Nora",
""
],
[
"Ghiglieri",
"Jacopo",
""
],
[
"Petreczky",
"Peter",
""
],
[
"Vairo",
"Antonio",
""
]
] |
We study the Polyakov loop and the correlator of two Polyakov loops at finite temperature in the weak-coupling regime. We calculate the Polyakov loop at order g^4. The calculation of the correlator of two Polyakov loops is performed at distances shorter than the inverse of the temperature and for electric screening masses larger than the Coulomb potential. In this regime, it is accurate up to order g^6. We also evaluate the Polyakov-loop correlator in an effective field theory framework that takes advantage of the hierarchy of energy scales in the problem and makes explicit the bound-state dynamics. In the effective field theory framework, we show that the Polyakov-loop correlator is at leading order in the multipole expansion the sum of a colour-singlet and a colour-octet quark-antiquark correlator, which are gauge invariant, and compute the corresponding colour-singlet and colour-octet free energies.
|
1908.11864
|
Wen Yin
|
Shintaro Eijima, Ryuichiro Kitano and Wen Yin
|
Throwing away antimatter via neutrino oscillations during the reheating
era
|
20pages, 1figure, v2: reference added, typo corrected
| null |
10.1088/1475-7516/2020/03/048
|
KEK-TH-2153
|
hep-ph astro-ph.CO gr-qc hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The simplest possibility to explain the baryon asymmetry of the Universe is
to assume that radiation is created asymmetrically between baryons and
anti-baryons after the inflation. We propose a new mechanism of this kind where
CP-violating flavor oscillations of left-handed leptons in the reheating era
distribute the lepton asymmetries partially into the right-handed neutrinos
while net asymmetry is not created. The asymmetry stored in the right-handed
neutrinos is later washed out by the lepton number violating decays, and it
ends up with the net lepton asymmetry in the Standard Model particles, which is
converted into the baryon asymmetry by the sphaleron process. This scenario
works for a range of masses of the right-handed neutrinos while no fine-tuning
among the masses is required. The reheating temperature of the Universe can be
as low as $O(10)$~TeV if we assume that the decays of inflatons in the
perturbative regime are responsible for the reheating. For the case of the
reheating via the dissipation effects, the reheating temperature can be as low
as $O(100)$~GeV.
|
[
{
"created": "Fri, 30 Aug 2019 17:49:40 GMT",
"version": "v1"
},
{
"created": "Mon, 16 Sep 2019 04:11:25 GMT",
"version": "v2"
}
] |
2020-04-01
|
[
[
"Eijima",
"Shintaro",
""
],
[
"Kitano",
"Ryuichiro",
""
],
[
"Yin",
"Wen",
""
]
] |
The simplest possibility to explain the baryon asymmetry of the Universe is to assume that radiation is created asymmetrically between baryons and anti-baryons after the inflation. We propose a new mechanism of this kind where CP-violating flavor oscillations of left-handed leptons in the reheating era distribute the lepton asymmetries partially into the right-handed neutrinos while net asymmetry is not created. The asymmetry stored in the right-handed neutrinos is later washed out by the lepton number violating decays, and it ends up with the net lepton asymmetry in the Standard Model particles, which is converted into the baryon asymmetry by the sphaleron process. This scenario works for a range of masses of the right-handed neutrinos while no fine-tuning among the masses is required. The reheating temperature of the Universe can be as low as $O(10)$~TeV if we assume that the decays of inflatons in the perturbative regime are responsible for the reheating. For the case of the reheating via the dissipation effects, the reheating temperature can be as low as $O(100)$~GeV.
|
1410.3779
|
C. A. Dominguez
|
C. A. Dominguez, L. A. Hernandez, K. Schilcher and H. Spiesberger
|
Chiral sum rules and vacuum condensates from tau-lepton decay data
|
Revised version with additional discussions/comments
| null |
10.1007/JHEP03(2015)053
|
UCT-TP-302/14, MITP/14-074
|
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
QCD finite energy sum rules, together with the latest updated ALEPH data on
hadronic decays of the tau-lepton are used in order to determine the vacuum
condensates of dimension $d=2$ and $d=4$. These data are also used to check the
validity of the Weinberg sum rules, and to determine the chiral condensates of
dimension $d=6$ and $d=8$, as well as the chiral correlator at zero momentum,
proportional to the counter term of the ${\cal{O}}(p^4)$ Lagrangian of chiral
perturbation theory, $\bar{L}_{10}$. Suitable (pinched) integration kernels are
introduced in the sum rules in order to suppress potential quark-hadron duality
violations. We find no compelling indications of duality violations in the
kinematic region above $s \simeq 2.2$ GeV$^2$ after using pinched integration
kernels.
|
[
{
"created": "Tue, 14 Oct 2014 17:52:16 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Jan 2015 08:10:15 GMT",
"version": "v2"
},
{
"created": "Thu, 22 Jan 2015 09:08:41 GMT",
"version": "v3"
},
{
"created": "Fri, 23 Jan 2015 11:02:43 GMT",
"version": "v4"
},
{
"created": "Mon, 16 Feb 2015 12:04:09 GMT",
"version": "v5"
}
] |
2015-06-23
|
[
[
"Dominguez",
"C. A.",
""
],
[
"Hernandez",
"L. A.",
""
],
[
"Schilcher",
"K.",
""
],
[
"Spiesberger",
"H.",
""
]
] |
QCD finite energy sum rules, together with the latest updated ALEPH data on hadronic decays of the tau-lepton are used in order to determine the vacuum condensates of dimension $d=2$ and $d=4$. These data are also used to check the validity of the Weinberg sum rules, and to determine the chiral condensates of dimension $d=6$ and $d=8$, as well as the chiral correlator at zero momentum, proportional to the counter term of the ${\cal{O}}(p^4)$ Lagrangian of chiral perturbation theory, $\bar{L}_{10}$. Suitable (pinched) integration kernels are introduced in the sum rules in order to suppress potential quark-hadron duality violations. We find no compelling indications of duality violations in the kinematic region above $s \simeq 2.2$ GeV$^2$ after using pinched integration kernels.
|
2303.03061
|
Mirzayusuf Musakhanov
|
Mirzayusuf Musakhanov
|
Gluons, light and heavy quarks and their interactions in the instanton
vacuum
|
arXiv admin note: text overlap with arXiv:2103.16628
| null | null | null |
hep-ph hep-th nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The instanton size $\rho$ and inter-instanton distance $R$ are the main
parameters of Instanton Liquid Model (ILM) of the QCD vacuum. Various estimates
show that $\rho\approx1/3$ fm and $R\approx1$ fm, and the corresponding packing
parameter $\kappa=\rho^{4}/R^{4}\approx0.01$. The strength of the light
quark-instanton interaction is sizable and close to that of the gluon-instanton
one since the dynamical light quark mass $M_{q}$ and dynamical gluon mass
$M_{g}$ are given by $M_{q}\approx M_{g}\approx 360$
MeV$\sim\kappa^{1/2}\rho^{-1}$. On the other hand, the strength of the heavy
quark-instanton interaction is weak - the direct instanton contribution to the
heavy quark mass $\Delta M_{Q}^{{\rm dir}}\approx70$ MeV$\sim\kappa\rho^{-1}.$
The instantons are responsible for mutual interactions among colored particles
which are crossing the field of the same instanton, like t'Hooft-like
interactions of $N_{f}$ light quarks ($N_{f}$ is the light quark flavors
number). The light quark propagators in the instanton field have zero modes,
which give dominant contributions. Within ILM we are able to derive the light
quarks determinants and the light quarks partition function. These tools
perfectly describe the light quark physics and its most important and basic
phenomena - the spontaneous breaking of the chiral symmetry (SBChS) in details.
These one allows us to find the properties of light and heavy quarks
interactions and get SBChS traces in light-heavy and heavy-heavy quarks
systems. So, we need to find heavy $Q\bar{Q}$ quarkonia spectra and their wave
functions. Here we have interplay of two scales: short
($\sim(M_{Q}v)^{-1}\leq0.15$ fm) perturbative QCD and large
($\sim(M_{Q}v^{2})^{-1}\sim0.5$ fm) nonperturbative QCD scales, where $v$ is
the velocity in $Q\bar{Q}$. We calculate the heavy quarks correlators with
perturbative corrections within ILM.
|
[
{
"created": "Mon, 6 Mar 2023 12:12:06 GMT",
"version": "v1"
}
] |
2023-03-07
|
[
[
"Musakhanov",
"Mirzayusuf",
""
]
] |
The instanton size $\rho$ and inter-instanton distance $R$ are the main parameters of Instanton Liquid Model (ILM) of the QCD vacuum. Various estimates show that $\rho\approx1/3$ fm and $R\approx1$ fm, and the corresponding packing parameter $\kappa=\rho^{4}/R^{4}\approx0.01$. The strength of the light quark-instanton interaction is sizable and close to that of the gluon-instanton one since the dynamical light quark mass $M_{q}$ and dynamical gluon mass $M_{g}$ are given by $M_{q}\approx M_{g}\approx 360$ MeV$\sim\kappa^{1/2}\rho^{-1}$. On the other hand, the strength of the heavy quark-instanton interaction is weak - the direct instanton contribution to the heavy quark mass $\Delta M_{Q}^{{\rm dir}}\approx70$ MeV$\sim\kappa\rho^{-1}.$ The instantons are responsible for mutual interactions among colored particles which are crossing the field of the same instanton, like t'Hooft-like interactions of $N_{f}$ light quarks ($N_{f}$ is the light quark flavors number). The light quark propagators in the instanton field have zero modes, which give dominant contributions. Within ILM we are able to derive the light quarks determinants and the light quarks partition function. These tools perfectly describe the light quark physics and its most important and basic phenomena - the spontaneous breaking of the chiral symmetry (SBChS) in details. These one allows us to find the properties of light and heavy quarks interactions and get SBChS traces in light-heavy and heavy-heavy quarks systems. So, we need to find heavy $Q\bar{Q}$ quarkonia spectra and their wave functions. Here we have interplay of two scales: short ($\sim(M_{Q}v)^{-1}\leq0.15$ fm) perturbative QCD and large ($\sim(M_{Q}v^{2})^{-1}\sim0.5$ fm) nonperturbative QCD scales, where $v$ is the velocity in $Q\bar{Q}$. We calculate the heavy quarks correlators with perturbative corrections within ILM.
|
1807.03799
|
Matthew Sievert
|
Matthew D. Sievert, Ivan Vitev
|
Quark branching in QCD matter to any order in opacity beyond the soft
gluon emission limit
|
41 pages, 10 figures
|
Phys. Rev. D 98, 094010 (2018)
|
10.1103/PhysRevD.98.094010
|
LA-UR-18-26751
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Cold nuclear matter effects in reactions with nuclei at a future electron-ion
collider (EIC) lead to a modification of semi-inclusive hadron production, jet
cross sections, and jet substructure when compared to the vacuum. At leading
order in the strong coupling, a jet produced at an EIC is initiated as an
energetic quark, and the process of this quark splitting into a quark-gluon
system underlies experimental observables. The spectrum of gluons associated
with the branching of this quark jet is heavily modified by multiple scattering
in a medium, allowing jet cross sections and jet substructure to be used as a
probe of the medium's properties. We present a formalism that allows us to
compute the gluon spectrum of a quark jet to an arbitrary order in opacity, the
average number of scatterings in the medium. This calculation goes beyond the
simplifying limit in which the gluon radiation is soft and can be interpreted
as energy loss of the quark, and it significantly extends previous work which
computes the full gluon spectrum only to first order in opacity. The
theoretical framework demonstrated here applies equally well to light parton
and heavy quark branching, and is easily generalizable to all in-medium
splitting processes.
|
[
{
"created": "Tue, 10 Jul 2018 18:00:27 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Nov 2018 17:11:24 GMT",
"version": "v2"
}
] |
2018-11-21
|
[
[
"Sievert",
"Matthew D.",
""
],
[
"Vitev",
"Ivan",
""
]
] |
Cold nuclear matter effects in reactions with nuclei at a future electron-ion collider (EIC) lead to a modification of semi-inclusive hadron production, jet cross sections, and jet substructure when compared to the vacuum. At leading order in the strong coupling, a jet produced at an EIC is initiated as an energetic quark, and the process of this quark splitting into a quark-gluon system underlies experimental observables. The spectrum of gluons associated with the branching of this quark jet is heavily modified by multiple scattering in a medium, allowing jet cross sections and jet substructure to be used as a probe of the medium's properties. We present a formalism that allows us to compute the gluon spectrum of a quark jet to an arbitrary order in opacity, the average number of scatterings in the medium. This calculation goes beyond the simplifying limit in which the gluon radiation is soft and can be interpreted as energy loss of the quark, and it significantly extends previous work which computes the full gluon spectrum only to first order in opacity. The theoretical framework demonstrated here applies equally well to light parton and heavy quark branching, and is easily generalizable to all in-medium splitting processes.
|
2006.13564
|
Jose Miguel No
|
Michael Gustafsson, Jose Miguel No, Maximiliano A. Rivera
|
Lepton number violating operators with standard model gauge fields: A
survey of neutrino masses from 3-loops and their link to dark matter
|
36 pages, 11 figures
| null |
10.1007/JHEP11(2020)070
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate neutrino mass generation scenarios where the lepton number
breaking new physics couples only to the Standard Model (SM) right-handed
charged lepton chirality. The lowest-order lepton number violating effective
operator which describes this framework is a unique dimension nine operator
involving SM gauge fields, $\mathcal{O}_9$. We find that there are two possible
classes of new physics scenarios giving rise to this $\mathcal{O}_9$ operator.
In these scenarios neutrino masses are induced radiatively via dark matter
interactions, linking the dark matter to a natural explanation for the
smallness of neutrino masses compared to the electroweak scale. We discuss the
phenomenology and existing constraints in the different neutrino mass models
within each class. In particular, we analyze the important interplay between
neutrino mixing and neutrinoless double $\beta$-decay in order to predict
characteristic signatures and disfavour certain scenarios.
|
[
{
"created": "Wed, 24 Jun 2020 08:54:12 GMT",
"version": "v1"
}
] |
2020-12-02
|
[
[
"Gustafsson",
"Michael",
""
],
[
"No",
"Jose Miguel",
""
],
[
"Rivera",
"Maximiliano A.",
""
]
] |
We investigate neutrino mass generation scenarios where the lepton number breaking new physics couples only to the Standard Model (SM) right-handed charged lepton chirality. The lowest-order lepton number violating effective operator which describes this framework is a unique dimension nine operator involving SM gauge fields, $\mathcal{O}_9$. We find that there are two possible classes of new physics scenarios giving rise to this $\mathcal{O}_9$ operator. In these scenarios neutrino masses are induced radiatively via dark matter interactions, linking the dark matter to a natural explanation for the smallness of neutrino masses compared to the electroweak scale. We discuss the phenomenology and existing constraints in the different neutrino mass models within each class. In particular, we analyze the important interplay between neutrino mixing and neutrinoless double $\beta$-decay in order to predict characteristic signatures and disfavour certain scenarios.
|
hep-ph/0010021
|
Hitoshi Murayama
|
Hitoshi Murayama (UC Berkeley, LBNL)
|
Dynamical (Super)Symmetry Breaking
|
8 pages. Plenary talk presented at 11th Rencontre de Blois,
"Frontiers of Matter," Blois, Loire Valley, France June 28 - 3 Jul, 1999
| null | null |
UCB-PTH-00/33, LBNL-46901
|
hep-ph
| null |
Dynamical Symmetry Breaking (DSB) is a concept theorists rely on very often
in the discussions of strong dynamics, model building, and hierarchy problems.
In this talk, I will discuss why this is such a permeating concept among
theorists and how they are used in understanding physics. I also briefly review
recent progress in using dynamical symmetry breaking to construct models of
supersymmetry breaking and fermion masses.
|
[
{
"created": "Tue, 3 Oct 2000 16:41:24 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Murayama",
"Hitoshi",
"",
"UC Berkeley, LBNL"
]
] |
Dynamical Symmetry Breaking (DSB) is a concept theorists rely on very often in the discussions of strong dynamics, model building, and hierarchy problems. In this talk, I will discuss why this is such a permeating concept among theorists and how they are used in understanding physics. I also briefly review recent progress in using dynamical symmetry breaking to construct models of supersymmetry breaking and fermion masses.
|
hep-ph/0305073
|
Satoshi Mishima
|
Satoshi Mishima, A. I. Sanda
|
Calculation of Magnetic Penguin Amplitudes in B -> phi K Decays using
PQCD Approach
|
15 pages, 3 figures, LaTeX with the PTP style, minor changes of typos
|
Prog.Theor.Phys. 110 (2003) 549-561
|
10.1143/PTP.110.549
|
DPNU-03-10
|
hep-ph
| null |
New physics contributions to B decays often arise through chromo-magnetic
penguin operators. To look for new physics effects in B decays, it is useful to
be able to estimate the hadronic matrix elements for the chromo-magnetic
operator. We compute this contribution to B ->phi K decays using PQCD methods.
It is shown that, if the Wilson coefficient of the new physics is same order of
magnitude as that of the Standard Model, this operator gives a non-negligible
contribution compared to that of the Standard Model (about 30%). We also
investigate the value of q^2, which is the momentum transferred by the gluon in
the chromo-magnetic penguin operator. We find that the expectation value <q^2>
is approximately M^2_B/4, in agreement with a naive guess. This result,
however, is very sensitive to the scale dependence of the Wilson coefficient.
We also show that the matrix element for the chromo-magnetic penguin operator
is independent of the choice of energy scale to a very good approximation.
|
[
{
"created": "Wed, 7 May 2003 18:29:54 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Sep 2003 05:56:14 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Mishima",
"Satoshi",
""
],
[
"Sanda",
"A. I.",
""
]
] |
New physics contributions to B decays often arise through chromo-magnetic penguin operators. To look for new physics effects in B decays, it is useful to be able to estimate the hadronic matrix elements for the chromo-magnetic operator. We compute this contribution to B ->phi K decays using PQCD methods. It is shown that, if the Wilson coefficient of the new physics is same order of magnitude as that of the Standard Model, this operator gives a non-negligible contribution compared to that of the Standard Model (about 30%). We also investigate the value of q^2, which is the momentum transferred by the gluon in the chromo-magnetic penguin operator. We find that the expectation value <q^2> is approximately M^2_B/4, in agreement with a naive guess. This result, however, is very sensitive to the scale dependence of the Wilson coefficient. We also show that the matrix element for the chromo-magnetic penguin operator is independent of the choice of energy scale to a very good approximation.
|
2210.06613
|
Krzysztof Marek Kutak
|
M. Abdullah Al-Mashad, A. van Hameren, H. Kakkad, P. Kotko, K. Kutak,
P. van Mechelen, S. Sapeta
|
Dijet azimuthal correlations in p-p and p-Pb collisions at forward LHC
calorimeters
|
14 pages
| null | null | null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present a state-of-the-art computation for the production of forward
dijets in proton-proton and proton-lead collisions at the LHC, in rapidity
domains covered by the ATLAS calorimeter and the planned FoCal extension of the
ALICE detector. We use the small-x improved TMD (ITMD) formalism, together with
collinearly improved TMD gluon distributions and full b-space Sudakov
resummation, and discuss nonperturbative corrections due to hadronization and
showers using the Pythia event generator. We observe that forward dijets in
proton-nucleus collisions at moderately low pT are excellent probes of
saturation effects, as the Sudakov resummation does not alter the suppression
of the cross section.
|
[
{
"created": "Wed, 12 Oct 2022 22:38:36 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Oct 2022 19:29:55 GMT",
"version": "v2"
}
] |
2022-10-28
|
[
[
"Al-Mashad",
"M. Abdullah",
""
],
[
"van Hameren",
"A.",
""
],
[
"Kakkad",
"H.",
""
],
[
"Kotko",
"P.",
""
],
[
"Kutak",
"K.",
""
],
[
"van Mechelen",
"P.",
""
],
[
"Sapeta",
"S.",
""
]
] |
We present a state-of-the-art computation for the production of forward dijets in proton-proton and proton-lead collisions at the LHC, in rapidity domains covered by the ATLAS calorimeter and the planned FoCal extension of the ALICE detector. We use the small-x improved TMD (ITMD) formalism, together with collinearly improved TMD gluon distributions and full b-space Sudakov resummation, and discuss nonperturbative corrections due to hadronization and showers using the Pythia event generator. We observe that forward dijets in proton-nucleus collisions at moderately low pT are excellent probes of saturation effects, as the Sudakov resummation does not alter the suppression of the cross section.
|
hep-ph/9608277
|
Liu Chun
|
Yuan-ben Dai, Chao-shang Huang, Ming-qiu Huang, and Chun Liu
|
QCD Sum Rule Analysis for the \Lambda_b to \Lambda_c Semileptonic Decay
|
LateX, 16 pages including 3 figs, to appear in Phys. Lett.B
|
Phys.Lett.B387:379-385,1996
|
10.1016/0370-2693(96)01029-5
|
AS-ITP-96-08
|
hep-ph
| null |
The 1/m_c and 1/m_b corrections to the \Lambda_b to \Lambda_c semi- leptonic
decay are analyzed by QCD sum rules. Within the framework of heavy quark
effective theory,the subleading baryonic Isgur-Wise func- tion of \Lambda_b to
\Lambda_c has been calculated. It is shown that the corrections due to the 1/m
Lagrangian insertion are negligibly small. The sizable 1/m_Q effect to the
decay lies only in the weak current. The decay spectrum and the branching ratio
are given.
|
[
{
"created": "Fri, 9 Aug 1996 01:08:30 GMT",
"version": "v1"
}
] |
2011-01-27
|
[
[
"Dai",
"Yuan-ben",
""
],
[
"Huang",
"Chao-shang",
""
],
[
"Huang",
"Ming-qiu",
""
],
[
"Liu",
"Chun",
""
]
] |
The 1/m_c and 1/m_b corrections to the \Lambda_b to \Lambda_c semi- leptonic decay are analyzed by QCD sum rules. Within the framework of heavy quark effective theory,the subleading baryonic Isgur-Wise func- tion of \Lambda_b to \Lambda_c has been calculated. It is shown that the corrections due to the 1/m Lagrangian insertion are negligibly small. The sizable 1/m_Q effect to the decay lies only in the weak current. The decay spectrum and the branching ratio are given.
|
1908.00909
|
Ayon Patra Dr.
|
Subhendra Mohanty, Ayon Patra and Tripurari Srivastava
|
MeV scale model of SIMP dark matter, neutrino mass and leptogenesis
|
22 pages, 11 figures, 3 tables. Comments are welcome
| null |
10.1088/1475-7516/2020/03/027
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider a simple extension of the Standard Model with two singlet scalar
fields and three heavy right-handed neutrinos. One of the scalar fields serves
as an MeV scale dark matter and its stability is ensured by the introduction of
an extra $Z_2$ symmetry. The second scalar (which is even under the $Z_2$
symmetry) generates the mass term of the scalar, contributes to the $3
\rightarrow 2$ annihilation process required for the correct relic density of
the dark matter and it also contributes to the leptogenesis. The right-handed
neutrinos are responsible for the generation of light neutrino masses through
Type-I seesaw mechanism. The decay of the heavy right-handed neutrino can
generate the lepton asymmetry which can then be converted to baryon asymmetry
through sphaleron transitions.
|
[
{
"created": "Fri, 2 Aug 2019 15:30:26 GMT",
"version": "v1"
}
] |
2020-03-18
|
[
[
"Mohanty",
"Subhendra",
""
],
[
"Patra",
"Ayon",
""
],
[
"Srivastava",
"Tripurari",
""
]
] |
We consider a simple extension of the Standard Model with two singlet scalar fields and three heavy right-handed neutrinos. One of the scalar fields serves as an MeV scale dark matter and its stability is ensured by the introduction of an extra $Z_2$ symmetry. The second scalar (which is even under the $Z_2$ symmetry) generates the mass term of the scalar, contributes to the $3 \rightarrow 2$ annihilation process required for the correct relic density of the dark matter and it also contributes to the leptogenesis. The right-handed neutrinos are responsible for the generation of light neutrino masses through Type-I seesaw mechanism. The decay of the heavy right-handed neutrino can generate the lepton asymmetry which can then be converted to baryon asymmetry through sphaleron transitions.
|
1508.05078
|
Gouranga Nayak
|
Gouranga C. Nayak
|
Correct Definition of the Gluon Fragmentation Function at High Energy
Colliders
|
13 pages latex. arXiv admin note: substantial text overlap with
arXiv:1506.02651, arXiv:1506.02593, arXiv:1508.01194
| null | null | null |
hep-ph hep-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Since the definition of the gluon to hadrons fragmentation amplitude
$<H,X|g>$ involves gluon field $Q^{\mu a}(x)$ corresponding to single gluon
incoming state $|g>$, the present definition of the gluon fragmentation
function at high energy colliders [which involves non-abelian field tensor
$F^{\mu \nu a}(x)=\partial^\mu Q^{\nu a}(x) -\partial^\nu Q^{\mu
a}(x)+gf^{abc}Q^{\mu b}(x)Q^{\nu c}(x)$ instead of $Q^{\mu a}(x)$ in the
initial state] is not consistent with the single gluon incoming state $|g>$. In
this paper we derive the correct definition of the gluon fragmentation function
at high energy colliders from first principles which is obtained from the
single gluon incoming state $|g>$ and is gauge invariant and is consistent with
the factorization theorem in QCD.
|
[
{
"created": "Thu, 20 Aug 2015 19:30:21 GMT",
"version": "v1"
}
] |
2015-08-21
|
[
[
"Nayak",
"Gouranga C.",
""
]
] |
Since the definition of the gluon to hadrons fragmentation amplitude $<H,X|g>$ involves gluon field $Q^{\mu a}(x)$ corresponding to single gluon incoming state $|g>$, the present definition of the gluon fragmentation function at high energy colliders [which involves non-abelian field tensor $F^{\mu \nu a}(x)=\partial^\mu Q^{\nu a}(x) -\partial^\nu Q^{\mu a}(x)+gf^{abc}Q^{\mu b}(x)Q^{\nu c}(x)$ instead of $Q^{\mu a}(x)$ in the initial state] is not consistent with the single gluon incoming state $|g>$. In this paper we derive the correct definition of the gluon fragmentation function at high energy colliders from first principles which is obtained from the single gluon incoming state $|g>$ and is gauge invariant and is consistent with the factorization theorem in QCD.
|
2401.17055
|
Wei Zhao
|
Wei Zhao and Hui Liu and Xitong Mei
|
Ultralight scalar and axion dark matter detection with atom
interferometers
|
5 pages, 3 figures
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The detection of dark matter is a challenging problem in modern physics. The
ultralight scalar and axion dark matter could induce the oscillation of the
nuclear charge radii and then oscillate the atomic transition frequency by
interacting with standard model particles. We compute the differential phase
shift caused by the scalar and axion dark matter in a pair of separated atom
interferometers and give the proposed constraints on the scalar dark matter
coupling parameters $d_g$ and $d_{\hat{m}}$ as well as the axion dark matter
coupling parameter $1/f_a$. Our results are expected to improve the current
detection level and complement with other experiments.
|
[
{
"created": "Tue, 30 Jan 2024 14:36:01 GMT",
"version": "v1"
}
] |
2024-01-31
|
[
[
"Zhao",
"Wei",
""
],
[
"Liu",
"Hui",
""
],
[
"Mei",
"Xitong",
""
]
] |
The detection of dark matter is a challenging problem in modern physics. The ultralight scalar and axion dark matter could induce the oscillation of the nuclear charge radii and then oscillate the atomic transition frequency by interacting with standard model particles. We compute the differential phase shift caused by the scalar and axion dark matter in a pair of separated atom interferometers and give the proposed constraints on the scalar dark matter coupling parameters $d_g$ and $d_{\hat{m}}$ as well as the axion dark matter coupling parameter $1/f_a$. Our results are expected to improve the current detection level and complement with other experiments.
|
hep-ph/9907360
|
Moultaka Gilbert
|
J.-L. Kneur and G. Moultaka
|
Phases in the gaugino sector: direct reconstruction of the basic
parameters and impact on the neutralino pair production
|
Latex, 28 pages, 10 figures
|
Phys.Rev. D61 (2000) 095003
|
10.1103/PhysRevD.61.095003
|
PM/99-30
|
hep-ph
| null |
We consider recovering analytically the (generally complex) parameters $\mu$,
$M_1$ and $M_2$ of the gaugino and Higgsino Lagrangian, from appropriate
physical input in the chargino and neutralino sectors. For given $\tan\beta$,
we obtain very simple analytic solutions for $M_2$, $| \mu|$, $Arg[\mu]$ in the
chargino sector and a twofold $| M_1 |$, $Arg[M_1]$ analytic solution in the
neutralino sector, assuming two chargino, two neutralino masses, and one of the
chargino mixing angles as physical input. The twofold ambiguity in the
neutralino parameters reconstruction may be essentially resolved by measuring
the $e^+e^- \to \chi^0_1 \chi^0_2$ production cross-section at future linear
collider energies, which we study explicitly with the phase dependences. Some
salient features and specific properties of this complex case gaugino "spectrum
inversion" are illustrated and compared with the similar inversion in the real
case. In particular, our algorithms exhibit in a direct and transparent way the
non-trivial theoretical correlation among the chargino and neutralino
parameters, and the resulting allowed domains when only a subset of the
required physical input masses and production cross-sections is known.
|
[
{
"created": "Wed, 14 Jul 1999 17:11:44 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Kneur",
"J. -L.",
""
],
[
"Moultaka",
"G.",
""
]
] |
We consider recovering analytically the (generally complex) parameters $\mu$, $M_1$ and $M_2$ of the gaugino and Higgsino Lagrangian, from appropriate physical input in the chargino and neutralino sectors. For given $\tan\beta$, we obtain very simple analytic solutions for $M_2$, $| \mu|$, $Arg[\mu]$ in the chargino sector and a twofold $| M_1 |$, $Arg[M_1]$ analytic solution in the neutralino sector, assuming two chargino, two neutralino masses, and one of the chargino mixing angles as physical input. The twofold ambiguity in the neutralino parameters reconstruction may be essentially resolved by measuring the $e^+e^- \to \chi^0_1 \chi^0_2$ production cross-section at future linear collider energies, which we study explicitly with the phase dependences. Some salient features and specific properties of this complex case gaugino "spectrum inversion" are illustrated and compared with the similar inversion in the real case. In particular, our algorithms exhibit in a direct and transparent way the non-trivial theoretical correlation among the chargino and neutralino parameters, and the resulting allowed domains when only a subset of the required physical input masses and production cross-sections is known.
|
1702.07572
|
Rados{\l}aw Kycia
|
Rados{\l}aw Kycia, Piotr Lebiedowicz, Antoni Szczurek, Jacek Turnau
|
Triple Regge exchange mechanisms of four-pion continuum production in
the $pp \to pp \pi^{+}\pi^{-}\pi^{+}\pi^{-}$ reaction
|
30 pages, 25 figures
|
Phys. Rev. D 95, 094020 (2017)
|
10.1103/PhysRevD.95.094020
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider exclusive multi-peripheral production of four charged pions in
proton-proton collisions at high energies with simultaneous exchange of three
pomerons/reggeons. The amplitude(s) for the genuine $2 \to 6$ process are
written in the Regge approach. The calculation is performed with the help of
the GenEx Monte Carlo code. Some corrections at low invariant masses in the
two-body subsystems are necessary for application of the Regge formalism. We
estimate the corresponding cross section and present differential distributions
in rapidity, transverse momenta and two- and four-pion invariant masses. The
cross section and the distributions depend on the value of the cut-off
parameter of a form factor correcting amplitudes for off-shellness of
$t$-channel pions. Rather large cross section is found for the whole phase
space ($\sigma \sim$ 1-5 $\mu$b, including absorption corrections). Relatively
large four-pion invariant masses are populated in the considered diffractive
mechanism compared to other mechanisms discussed so far in the context of
four-pion production. We investigate whether the triple Regge exchange
processes could be identified with the existing LHC detectors. We consider the
case of ATLAS and ALICE cuts. The ATLAS (or CMS) has better chances to identify
the process in the region of large invariant masses $M_{4 \pi} > 10$ GeV. In
the case of the ALICE experiment the considered mechanism competes with other
mechanisms (production of $\sigma \sigma$, $\rho \rho$ pairs or single
resonances) and cannot be unambiguously identified.
|
[
{
"created": "Fri, 24 Feb 2017 13:26:50 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Mar 2017 21:07:08 GMT",
"version": "v2"
}
] |
2017-05-31
|
[
[
"Kycia",
"Radosław",
""
],
[
"Lebiedowicz",
"Piotr",
""
],
[
"Szczurek",
"Antoni",
""
],
[
"Turnau",
"Jacek",
""
]
] |
We consider exclusive multi-peripheral production of four charged pions in proton-proton collisions at high energies with simultaneous exchange of three pomerons/reggeons. The amplitude(s) for the genuine $2 \to 6$ process are written in the Regge approach. The calculation is performed with the help of the GenEx Monte Carlo code. Some corrections at low invariant masses in the two-body subsystems are necessary for application of the Regge formalism. We estimate the corresponding cross section and present differential distributions in rapidity, transverse momenta and two- and four-pion invariant masses. The cross section and the distributions depend on the value of the cut-off parameter of a form factor correcting amplitudes for off-shellness of $t$-channel pions. Rather large cross section is found for the whole phase space ($\sigma \sim$ 1-5 $\mu$b, including absorption corrections). Relatively large four-pion invariant masses are populated in the considered diffractive mechanism compared to other mechanisms discussed so far in the context of four-pion production. We investigate whether the triple Regge exchange processes could be identified with the existing LHC detectors. We consider the case of ATLAS and ALICE cuts. The ATLAS (or CMS) has better chances to identify the process in the region of large invariant masses $M_{4 \pi} > 10$ GeV. In the case of the ALICE experiment the considered mechanism competes with other mechanisms (production of $\sigma \sigma$, $\rho \rho$ pairs or single resonances) and cannot be unambiguously identified.
|
2403.20064
|
Zachary Draper
|
Zachary T. Draper and Stephen R. Sharpe
|
Three-particle formalism for multiple channels: the $\eta \pi \pi + K
\overline K \pi$ system in isosymmetric QCD
|
49 pages, no figures. v2: Fixed typos, added additional comments to
the conclusion, made other minor changes
| null |
10.1007/JHEP07(2024)083
| null |
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We generalize previous three-particle finite-volume formalisms to allow for
multiple three-particle channels. For definiteness, we focus on the two-channel
$\eta \pi \pi$ and $K \overline K \pi$ system in isosymmetric QCD, considering
the positive $G$ parity sector of the latter channel, and neglecting the
coupling to modes with four or more particles. The formalism we obtain is thus
appropriate to study the $b_1(1235)$ and $\eta(1295)$ resonances. The
derivation is made in the generic relativistic field theory approach using the
time-ordered perturbation theory method. We study how the resulting
quantization condition reduces to that for a single three-particle channel when
one drops below the upper ($K\overline K \pi$) threshold. We also present
parametrizations of the three-particle K matrices that enter into the
formalism.
|
[
{
"created": "Fri, 29 Mar 2024 08:55:34 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Jul 2024 18:35:08 GMT",
"version": "v2"
}
] |
2024-07-16
|
[
[
"Draper",
"Zachary T.",
""
],
[
"Sharpe",
"Stephen R.",
""
]
] |
We generalize previous three-particle finite-volume formalisms to allow for multiple three-particle channels. For definiteness, we focus on the two-channel $\eta \pi \pi$ and $K \overline K \pi$ system in isosymmetric QCD, considering the positive $G$ parity sector of the latter channel, and neglecting the coupling to modes with four or more particles. The formalism we obtain is thus appropriate to study the $b_1(1235)$ and $\eta(1295)$ resonances. The derivation is made in the generic relativistic field theory approach using the time-ordered perturbation theory method. We study how the resulting quantization condition reduces to that for a single three-particle channel when one drops below the upper ($K\overline K \pi$) threshold. We also present parametrizations of the three-particle K matrices that enter into the formalism.
|
2210.01993
|
Daisuke Jido
|
Takahiro Saionji, Daisuke Jido, Masayasu Harada
|
Inverse mass ordering of light scalar mesons in the Nambu Jona-Lasinio
model
|
17 pages, 3 figures
| null | null | null |
hep-ph nucl-th
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
The masses of the low-lying scalar mesons are investigated in the
three-flavor Nambu Jona-Lasinio (NJL) model by treating the scalar mesons as
composite objects of a quark and an antiquark. It is known that a simple $\bar
qq$ picture fails to reproduce so-called inverse mass ordering for the scalar
mesons. Recently a new mechanism to reproduce the observed mass spectrum of the
scalar mesons was proposed in a linear sigma model by introducing flavor
symmetry breaking induced by the U(1) axial anomaly. Motivated by this
proposal, we examine whether this new mechanism works also in the NJL model. By
calculating the scalar meson masses, we find that the NJL model reproduces the
observed mass ordering with sufficient strength of the new term. With this
mechanism, it turns out that the constituent strange quark mass gets degenerate
to that of the up and down quark if the inverse mass ordering is reproduced. We
also discuss the scalar diquark masses to check the consistency of the
degeneracy of the constituent quark masses with the light baryon masses.
|
[
{
"created": "Wed, 5 Oct 2022 02:56:53 GMT",
"version": "v1"
}
] |
2022-10-06
|
[
[
"Saionji",
"Takahiro",
""
],
[
"Jido",
"Daisuke",
""
],
[
"Harada",
"Masayasu",
""
]
] |
The masses of the low-lying scalar mesons are investigated in the three-flavor Nambu Jona-Lasinio (NJL) model by treating the scalar mesons as composite objects of a quark and an antiquark. It is known that a simple $\bar qq$ picture fails to reproduce so-called inverse mass ordering for the scalar mesons. Recently a new mechanism to reproduce the observed mass spectrum of the scalar mesons was proposed in a linear sigma model by introducing flavor symmetry breaking induced by the U(1) axial anomaly. Motivated by this proposal, we examine whether this new mechanism works also in the NJL model. By calculating the scalar meson masses, we find that the NJL model reproduces the observed mass ordering with sufficient strength of the new term. With this mechanism, it turns out that the constituent strange quark mass gets degenerate to that of the up and down quark if the inverse mass ordering is reproduced. We also discuss the scalar diquark masses to check the consistency of the degeneracy of the constituent quark masses with the light baryon masses.
|
hep-ph/0007308
|
John R. Hiller
|
J.R. Hiller
|
Methods for the nonperturbative approximation of form factors and
scattering amplitudes
|
4 pages, 1 figure; LaTeX, aipproc.sty, epsf.sty; to appear in the
proceedings of the 7th Conference on the Intersections of Particle and
Nuclear Physics, Quebec City, May 22-28, 2000
|
AIP Conf.Proc. 549 (2002) 399-402
|
10.1063/1.1345282
|
UMN-D-00-4
|
hep-ph
| null |
Methods are described for the nonperturbative calculation of wave functions
and scattering amplitudes in light-cone quantization. Form factors are computed
from the boost-invariant wave functions, which appear as coefficients in a
Fock-state expansion of the field-theoretic eigenstate. A technique is proposed
for calculating scattering amplitudes from matrix elements of a T operator
between such composite-particle eigenstates.
|
[
{
"created": "Wed, 26 Jul 2000 22:10:54 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Hiller",
"J. R.",
""
]
] |
Methods are described for the nonperturbative calculation of wave functions and scattering amplitudes in light-cone quantization. Form factors are computed from the boost-invariant wave functions, which appear as coefficients in a Fock-state expansion of the field-theoretic eigenstate. A technique is proposed for calculating scattering amplitudes from matrix elements of a T operator between such composite-particle eigenstates.
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.