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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0805.0627
|
Hrayr Matevosyan
|
Hrayr H. Matevosyan, Adam P. Szczepaniak, Patrick O. Bowman
|
A Numerical Approach to Coulomb Gauge QCD
| null |
Phys.Rev.D78:014033,2008
|
10.1103/PhysRevD.78.014033
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We calculate the ghost two-point function in Coulomb gauge QCD with a simple
model vacuum gluon wavefunction using Monte Carlo integration. This approach
extends the previous analytic studies of the ghost propagator with this ansatz,
where a ladder-rainbow expansion was unavoidable for calculating the path
integral over gluon field configurations. The new approach allows us to study
the possible critical behavior of the coupling constant, as well as the Coulomb
potential derived from the ghost dressing function. We demonstrate that IR
enhancement of the ghost correlator or Coulomb form factor fails to
quantitatively reproduce confinement using Gaussian vacuum wavefunctional.
|
[
{
"created": "Tue, 6 May 2008 01:38:45 GMT",
"version": "v1"
},
{
"created": "Thu, 3 Jul 2008 14:58:31 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Matevosyan",
"Hrayr H.",
""
],
[
"Szczepaniak",
"Adam P.",
""
],
[
"Bowman",
"Patrick O.",
""
]
] |
We calculate the ghost two-point function in Coulomb gauge QCD with a simple model vacuum gluon wavefunction using Monte Carlo integration. This approach extends the previous analytic studies of the ghost propagator with this ansatz, where a ladder-rainbow expansion was unavoidable for calculating the path integral over gluon field configurations. The new approach allows us to study the possible critical behavior of the coupling constant, as well as the Coulomb potential derived from the ghost dressing function. We demonstrate that IR enhancement of the ghost correlator or Coulomb form factor fails to quantitatively reproduce confinement using Gaussian vacuum wavefunctional.
|
2402.12460
|
Dean Robinson
|
Claudio Andrea Manzari, Dean J. Robinson
|
On-shell recursion and holomorphic HQET for heavy quark hadronic
resonances
|
65 pages, 6 figures, 1 table
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We develop a new theoretical framework for the treatment of heavy quark (HQ)
resonances within heavy quark effective theory (HQET). This framework uses
on-shell recursion techniques to express the resonant amplitude as a product of
on-shell subamplitudes, which allows one to employ a form-factor representation
of the hadronic matrix elements and to obtain an HQ expansion, but at the price
of introducing complex momenta. We construct a generalized "holomorphic HQET"
onto which such complex-momentum matrix elements can be matched, and we show
that $PT$ symmetry ensures the Isgur-Wise functions (and the perturbative
corrections) become holomorphic functions of the complex recoil parameter with
real coefficients. They are thus an analytic continuation of the standard HQET
description. This framework admits a HQ hadron (strong decay) width expansion.
At second order, we show it is in good agreement with data for the
$B_{1(2)}^{(*)}$ and $D_{1(2)}^{(*)}$ HQ doublets. Taking the $\bar{B} \to
(D_1^*(1^-) \to D\pi)l\nu$ system as an example, we compute the holomorphic
HQET expansion to first order, as well as the complex-momentum on-shell
subamplitudes. A toy numerical study of the resulting differential rates
demonstrates that this framework generates HQ resonance lineshapes with large
tails, resembling those seen in data.
|
[
{
"created": "Mon, 19 Feb 2024 19:05:54 GMT",
"version": "v1"
}
] |
2024-02-21
|
[
[
"Manzari",
"Claudio Andrea",
""
],
[
"Robinson",
"Dean J.",
""
]
] |
We develop a new theoretical framework for the treatment of heavy quark (HQ) resonances within heavy quark effective theory (HQET). This framework uses on-shell recursion techniques to express the resonant amplitude as a product of on-shell subamplitudes, which allows one to employ a form-factor representation of the hadronic matrix elements and to obtain an HQ expansion, but at the price of introducing complex momenta. We construct a generalized "holomorphic HQET" onto which such complex-momentum matrix elements can be matched, and we show that $PT$ symmetry ensures the Isgur-Wise functions (and the perturbative corrections) become holomorphic functions of the complex recoil parameter with real coefficients. They are thus an analytic continuation of the standard HQET description. This framework admits a HQ hadron (strong decay) width expansion. At second order, we show it is in good agreement with data for the $B_{1(2)}^{(*)}$ and $D_{1(2)}^{(*)}$ HQ doublets. Taking the $\bar{B} \to (D_1^*(1^-) \to D\pi)l\nu$ system as an example, we compute the holomorphic HQET expansion to first order, as well as the complex-momentum on-shell subamplitudes. A toy numerical study of the resulting differential rates demonstrates that this framework generates HQ resonance lineshapes with large tails, resembling those seen in data.
|
hep-ph/0612365
|
Bumseok Kyae
|
Ian-Woo Kim, Jihn E. Kim, Bumseok Kyae
|
Harmless R-parity violation from Z_{12-I} compactification of E_8 X E_8'
heterotic string
|
14 pages, revtex4 format
|
Phys.Lett.B647:275-281,2007
|
10.1016/j.physletb.2007.02.020
|
SNUTP 06-014, KIAS-P06069
|
hep-ph hep-th
| null |
In a recent $\Z_{12-I}$ orbifold model, an approximate $Z_2$ symmetry which
forbids the baryon number violating operators up to sufficiently high orders is
found. The dimension-4 $\Delta B\ne 0$ operators of the MSSM fields occur at
dimension 10. The effective dimension-5 $\Delta B\ne 0$ operators derived from
these are harmless if some VEVs of neutral singlets are O(1/10) times the
string scale. The main reason for forbidding these $\Delta B\ne 0$ operators up
to such a high order is the large order N=12 of $\Z_N$ since the $H$-momentum
rule is $(-1,1,1)$ mod (12, 3, 12). For a lower order $N<12$, the $\Delta B\ne
0$ operators would appear at lower dimensions.
|
[
{
"created": "Fri, 29 Dec 2006 18:37:46 GMT",
"version": "v1"
},
{
"created": "Sat, 6 Jan 2007 05:52:05 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Kim",
"Ian-Woo",
""
],
[
"Kim",
"Jihn E.",
""
],
[
"Kyae",
"Bumseok",
""
]
] |
In a recent $\Z_{12-I}$ orbifold model, an approximate $Z_2$ symmetry which forbids the baryon number violating operators up to sufficiently high orders is found. The dimension-4 $\Delta B\ne 0$ operators of the MSSM fields occur at dimension 10. The effective dimension-5 $\Delta B\ne 0$ operators derived from these are harmless if some VEVs of neutral singlets are O(1/10) times the string scale. The main reason for forbidding these $\Delta B\ne 0$ operators up to such a high order is the large order N=12 of $\Z_N$ since the $H$-momentum rule is $(-1,1,1)$ mod (12, 3, 12). For a lower order $N<12$, the $\Delta B\ne 0$ operators would appear at lower dimensions.
|
2110.09392
|
Lucia Popa
|
Lucia Aurelia Popa (Institute of Space Science Bucharest-Magurele,
Ro-077125 Romania)
|
Search for dark Higgs inflaton with curvature couplings at LHC
experiments
|
16 pages, 7 figures
| null | null | null |
hep-ph astro-ph.CO
|
http://creativecommons.org/licenses/by/4.0/
|
We analyse the dark Higgs inflation model with curvature corrections and
explore the possibility to test its predictions by the particle physics
experiments at LHC.
We show that the dark Higgs inflation model with curvature corrections is
strongly favoured by the present cosmological observations. The cosmological
predictions of this model, including the quantum corrections of dark Higgs
coupling constants and the uncertainty in estimation of the reheating
temperature, lead to the dark Higgs mass $m_{\phi}=0.919 \pm$ 0.211 GeV and the
mixing angle $\theta =1.492 \pm$ 0.045 (at 68\% CL). We evaluate the FASER and
MAPP-1 experiments reach for dark Higgs inflaton mass and mixing angle in the
95\% CL cosmological confidence region for an integrated luminosity of
3ab$^{-1}$ at 13 TeV LHC, assuming 100\% detection efficiency.
We conclude that the dark Higgs inflation model with curvature corrections is
a compelling inflation scenario based on particle physics theory favoured by
the present cosmological measurements that leaves imprints in the dark Higgs
boson searchers at LHC.
|
[
{
"created": "Mon, 18 Oct 2021 15:23:33 GMT",
"version": "v1"
}
] |
2021-10-19
|
[
[
"Popa",
"Lucia Aurelia",
"",
"Institute of Space Science Bucharest-Magurele,\n Ro-077125 Romania"
]
] |
We analyse the dark Higgs inflation model with curvature corrections and explore the possibility to test its predictions by the particle physics experiments at LHC. We show that the dark Higgs inflation model with curvature corrections is strongly favoured by the present cosmological observations. The cosmological predictions of this model, including the quantum corrections of dark Higgs coupling constants and the uncertainty in estimation of the reheating temperature, lead to the dark Higgs mass $m_{\phi}=0.919 \pm$ 0.211 GeV and the mixing angle $\theta =1.492 \pm$ 0.045 (at 68\% CL). We evaluate the FASER and MAPP-1 experiments reach for dark Higgs inflaton mass and mixing angle in the 95\% CL cosmological confidence region for an integrated luminosity of 3ab$^{-1}$ at 13 TeV LHC, assuming 100\% detection efficiency. We conclude that the dark Higgs inflation model with curvature corrections is a compelling inflation scenario based on particle physics theory favoured by the present cosmological measurements that leaves imprints in the dark Higgs boson searchers at LHC.
|
0803.3229
|
Jonathan Rosner
|
Cheng-Wei Chiang, Michael Gronau, and Jonathan L. Rosner
|
Examination of Flavor Symmetry in $B, B_s \to K \pi$ Decays
|
10 pages, 4 figures. Misprints in some exponents corrected; one
experimental value and some discussion updated
|
Phys.Lett.B664:169-173,2008
|
10.1016/j.physletb.2008.05.017
|
SLAC-PUB-13184, EFI 08-04
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study a relation between the weak phase $\gamma$ and the rates and CP
asymmetries of several $K \pi$ decays of $B^+$, $B^0$, and $B_s$, emphasizing
the impact of the latter measurements. Current data indicate large SU(3)
breaking in the strong phases or failure of factorization (including its
application to penguin amplitudes) in $K \pi$ modes of $B^0$ and $B_s$. SU(3)
and factorization only remain approximately valid if the branching ratio for
$B_s \to K^- \pi^+$ exceeds its current value of $(5.27 \pm 1.17) \times
10^{-6}$ by at least 42%, or if a parameter $\xi$ describing ratios of form
factors and decay constants is shifted from its nominal value by more than
twice its estimated error.
|
[
{
"created": "Sat, 22 Mar 2008 21:10:13 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Mar 2008 15:03:17 GMT",
"version": "v2"
},
{
"created": "Sat, 26 Apr 2008 14:43:49 GMT",
"version": "v3"
}
] |
2008-11-26
|
[
[
"Chiang",
"Cheng-Wei",
""
],
[
"Gronau",
"Michael",
""
],
[
"Rosner",
"Jonathan L.",
""
]
] |
We study a relation between the weak phase $\gamma$ and the rates and CP asymmetries of several $K \pi$ decays of $B^+$, $B^0$, and $B_s$, emphasizing the impact of the latter measurements. Current data indicate large SU(3) breaking in the strong phases or failure of factorization (including its application to penguin amplitudes) in $K \pi$ modes of $B^0$ and $B_s$. SU(3) and factorization only remain approximately valid if the branching ratio for $B_s \to K^- \pi^+$ exceeds its current value of $(5.27 \pm 1.17) \times 10^{-6}$ by at least 42%, or if a parameter $\xi$ describing ratios of form factors and decay constants is shifted from its nominal value by more than twice its estimated error.
|
0708.0248
|
Carlos E. Yaguna
|
Carlos E. Yaguna (UCLA)
|
Higgs decays in supersymmetric models with light neutralinos
|
9 pages, 5 figures
|
Phys.Rev.D76:075017,2007
|
10.1103/PhysRevD.76.075017
| null |
hep-ph
| null |
In the Minimal Supersymmetric Standard Model, neutralinos lighter than 50 GeV
are compatible with all accelerator, precision, and cosmological bounds. Such
neutralinos might constitute a relevant decay channel for the Higgs boson,
modifying its expected signatures at hadron colliders. We study the branching
ratio h --> \chi\chi and determine the region in the supersymmetric parameter
space where it is sizable. We have found that, in fact, the Higgs may
dominantly decay into neutralino pairs. Besides, as a result of this new
channel, the branching ratio into visible modes, such as h --> \gamma\gamma,
gets suppressed.
|
[
{
"created": "Thu, 2 Aug 2007 00:47:34 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Yaguna",
"Carlos E.",
"",
"UCLA"
]
] |
In the Minimal Supersymmetric Standard Model, neutralinos lighter than 50 GeV are compatible with all accelerator, precision, and cosmological bounds. Such neutralinos might constitute a relevant decay channel for the Higgs boson, modifying its expected signatures at hadron colliders. We study the branching ratio h --> \chi\chi and determine the region in the supersymmetric parameter space where it is sizable. We have found that, in fact, the Higgs may dominantly decay into neutralino pairs. Besides, as a result of this new channel, the branching ratio into visible modes, such as h --> \gamma\gamma, gets suppressed.
|
1909.02312
|
Zeren Simon Wang
|
Monica D'Onofrio, Oliver Fischer, Zeren Simon Wang
|
Searching for Dark Photons at the LHeC and FCC-he
|
9 pages, 5 figures; v2: 10 pages, 6 figures, accepted for publication
in Physical Review D
|
Phys. Rev. D 101, 015020 (2020)
|
10.1103/PhysRevD.101.015020
|
APCTP Pre2019-023
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Extensions of the Standard Model (SM) gauge group with a new $U(1)_X$ predict
an additional gauge boson. Through kinetic mixing with the SM photons featured
by a coupling $\epsilon$, the ensuing so-called dark photons $\gamma'$, which
acquire mass as a result of the breaking of the gauge group $U(1)_X$, can
interact with the SM field content. These massive dark photons can therefore
decay to pairs of leptons, hadrons, or quarks, depending on their mass
$m_{\gamma'}$. In this work, we discuss searches for dark photons in the mass
range around and below one GeV at the LHeC and FCC-he colliders. The signal is
given by the displaced decays of the long-lived dark photon into two charged
fermions. We discuss the impact of conceivable irreducible (SM and
machine-related) backgrounds and different signal efficiencies. Our estimates
show that the LHeC and FCC-he can test a domain that is complementary to other
present and planned experiments.
|
[
{
"created": "Thu, 5 Sep 2019 10:53:43 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Jan 2020 13:07:20 GMT",
"version": "v2"
}
] |
2020-02-05
|
[
[
"D'Onofrio",
"Monica",
""
],
[
"Fischer",
"Oliver",
""
],
[
"Wang",
"Zeren Simon",
""
]
] |
Extensions of the Standard Model (SM) gauge group with a new $U(1)_X$ predict an additional gauge boson. Through kinetic mixing with the SM photons featured by a coupling $\epsilon$, the ensuing so-called dark photons $\gamma'$, which acquire mass as a result of the breaking of the gauge group $U(1)_X$, can interact with the SM field content. These massive dark photons can therefore decay to pairs of leptons, hadrons, or quarks, depending on their mass $m_{\gamma'}$. In this work, we discuss searches for dark photons in the mass range around and below one GeV at the LHeC and FCC-he colliders. The signal is given by the displaced decays of the long-lived dark photon into two charged fermions. We discuss the impact of conceivable irreducible (SM and machine-related) backgrounds and different signal efficiencies. Our estimates show that the LHeC and FCC-he can test a domain that is complementary to other present and planned experiments.
|
1705.05711
|
Alexander A. Osipov
|
A. A. Osipov, A. A. Pivovarov, M. K. Volkov
|
The anomalous decay $f_1(1285)\to\rho\gamma$ and related processes
|
7 pages, 1 figure, appear in Physical Review D
|
Phys. Rev. D 96, 054012 (2017)
|
10.1103/PhysRevD.96.054012
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We work out the low-energy expansion of the anomalous
$f_1(1285)\to\rho\gamma$ decay amplitude by using the Nambu--Jona-Lasinio model
with $U(2)\times U(2)$ chiral symmetric four-quark interactions in the
one-quark-loop approximation. The related processes $f_1(1285)\to\omega\gamma$,
$a_1(1260)\to\omega\gamma$, and $a_1(1260)\to\rho\gamma$, are also considered.
An effective meson Lagrangian responsible for $f_1\rho\gamma$,
$f_1\omega\gamma$, $a_1\rho\gamma$ and $a_1\omega\gamma$ interactions is found.
The predicted radiative decay widths, $\Gamma_{f_1\to\rho^0\gamma}=311\
\mbox{keV}$, $\Gamma_{f_1\to\omega\gamma}=34.3\ \mbox{keV}$,
$\Gamma_{a_1\to\rho^0\gamma}=26.8\ \mbox{keV}$,
$\Gamma_{a_1\to\omega\gamma}=238\ \mbox{keV}$, allow an experimental test of
the hypothesis that $f_1(1285)$ and $a_1(1260)$-mesons have a quark-antiquark
nature. At present, only the $f_1(1285)\to\rho\gamma$ decay has been measured.
Our result is in remarkably good agreement with the recent data of CLAS
Collaboration $\Gamma_{f_1\to\rho^0\gamma}=453\pm 177\ \mbox{keV}$, but
disagrees with the PDG-based estimate of $\Gamma_{f_1\to\rho^0\gamma}=1326\pm
313\ \mbox{keV}$. The calculations presented require a minimum of theoretical
input, and are shown to be consistent with the non-renormalization theorems of
QCD.
|
[
{
"created": "Tue, 16 May 2017 14:02:34 GMT",
"version": "v1"
},
{
"created": "Sun, 20 Aug 2017 11:03:37 GMT",
"version": "v2"
}
] |
2017-09-20
|
[
[
"Osipov",
"A. A.",
""
],
[
"Pivovarov",
"A. A.",
""
],
[
"Volkov",
"M. K.",
""
]
] |
We work out the low-energy expansion of the anomalous $f_1(1285)\to\rho\gamma$ decay amplitude by using the Nambu--Jona-Lasinio model with $U(2)\times U(2)$ chiral symmetric four-quark interactions in the one-quark-loop approximation. The related processes $f_1(1285)\to\omega\gamma$, $a_1(1260)\to\omega\gamma$, and $a_1(1260)\to\rho\gamma$, are also considered. An effective meson Lagrangian responsible for $f_1\rho\gamma$, $f_1\omega\gamma$, $a_1\rho\gamma$ and $a_1\omega\gamma$ interactions is found. The predicted radiative decay widths, $\Gamma_{f_1\to\rho^0\gamma}=311\ \mbox{keV}$, $\Gamma_{f_1\to\omega\gamma}=34.3\ \mbox{keV}$, $\Gamma_{a_1\to\rho^0\gamma}=26.8\ \mbox{keV}$, $\Gamma_{a_1\to\omega\gamma}=238\ \mbox{keV}$, allow an experimental test of the hypothesis that $f_1(1285)$ and $a_1(1260)$-mesons have a quark-antiquark nature. At present, only the $f_1(1285)\to\rho\gamma$ decay has been measured. Our result is in remarkably good agreement with the recent data of CLAS Collaboration $\Gamma_{f_1\to\rho^0\gamma}=453\pm 177\ \mbox{keV}$, but disagrees with the PDG-based estimate of $\Gamma_{f_1\to\rho^0\gamma}=1326\pm 313\ \mbox{keV}$. The calculations presented require a minimum of theoretical input, and are shown to be consistent with the non-renormalization theorems of QCD.
|
hep-ph/0510017
|
Nguyen van Hieu
|
Nguyen Van Hieu and Nguyen Bich Ha
|
Quantum Theory of Electron Transport Through Single-Level Quantum Dot
| null | null | null | null |
hep-ph
| null |
A new approach in the quantum theory of few-electron nanoelectronic devices
-- the S-matrix approach -- is presented in a simple example: a single-electron
transistor consisting of a single-level quantum dot connected with two metallic
leads through the corresponding potential barriers. The electron transport
through the quantum dot due to the electron tunneling between the dot and the
leads is studied. The strong Coulomb repulsion between the electrons in the dot
is taken into account exactly, while the tunneling between the dot and the
leads, considered as a small perturbation, is studied by means of the
perturbation theory. For summing up the infinite perturbation theory series we
apply the Green function technique and the Heisenberg equation of motion of the
electron annihilation and creation operators. The matrix elements of the
transition processes include both the direct and crossing terms, so that there
is no need to use the non-crossing approximation (NCA). The explicit expression
of the electron transport current is derived.
|
[
{
"created": "Mon, 3 Oct 2005 08:24:03 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Van Hieu",
"Nguyen",
""
],
[
"Ha",
"Nguyen Bich",
""
]
] |
A new approach in the quantum theory of few-electron nanoelectronic devices -- the S-matrix approach -- is presented in a simple example: a single-electron transistor consisting of a single-level quantum dot connected with two metallic leads through the corresponding potential barriers. The electron transport through the quantum dot due to the electron tunneling between the dot and the leads is studied. The strong Coulomb repulsion between the electrons in the dot is taken into account exactly, while the tunneling between the dot and the leads, considered as a small perturbation, is studied by means of the perturbation theory. For summing up the infinite perturbation theory series we apply the Green function technique and the Heisenberg equation of motion of the electron annihilation and creation operators. The matrix elements of the transition processes include both the direct and crossing terms, so that there is no need to use the non-crossing approximation (NCA). The explicit expression of the electron transport current is derived.
|
0901.1185
|
C. Hanhart
|
Bochao Liu, Markus Buescher, Feng-Kun Guo, Christoph Hanhart, Ulf-G.
Mei{\ss}ner
|
Final state interactions in the decays J/psi->VPP
|
9 figures, 13 pages
|
Eur.Phys.J.C63:93-99,2009
|
10.1140/epjc/s10052-009-1083-2
|
FZJ-IKP-TH-2009-02, HISKP-TH-09/03
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate the interplay between crossed channel final state interactions
and the constraints from two--particle unitarity for the reactions J/psi->V pi
pi and VK\bar K, where V is either omega or phi. Using a model where the
parameters are largely constrained by other sources, we find that, although
small, crossed channel final state interaction can influence the amplitudes
considerably, in special areas of phase space. These results cast doubt on the
inapplicability of unitarity constraints on production amplitudes as recently
claimed in the literature.
|
[
{
"created": "Fri, 9 Jan 2009 08:51:39 GMT",
"version": "v1"
}
] |
2014-11-18
|
[
[
"Liu",
"Bochao",
""
],
[
"Buescher",
"Markus",
""
],
[
"Guo",
"Feng-Kun",
""
],
[
"Hanhart",
"Christoph",
""
],
[
"Meißner",
"Ulf-G.",
""
]
] |
We investigate the interplay between crossed channel final state interactions and the constraints from two--particle unitarity for the reactions J/psi->V pi pi and VK\bar K, where V is either omega or phi. Using a model where the parameters are largely constrained by other sources, we find that, although small, crossed channel final state interaction can influence the amplitudes considerably, in special areas of phase space. These results cast doubt on the inapplicability of unitarity constraints on production amplitudes as recently claimed in the literature.
|
2212.13263
|
Marco Gorghetto
|
Marco Gorghetto, Edward Hardy
|
Post-inflationary axions: a minimal target for axion haloscopes
|
20 pages + appendices
| null |
10.1007/JHEP05(2023)030
| null |
hep-ph hep-ex
|
http://creativecommons.org/licenses/by/4.0/
|
An axion-like-particle (ALP) in the post-inflationary scenario with domain
wall number $N>1$ can be dark matter if the residual $\mathbb{Z}_N$ symmetry
has a small explicit breaking. Although we cannot determine the full dynamics
of the system reliably, we provide evidence that such an ALP can account for
the observed dark matter abundance while having a relatively small decay
constant and consequently a possibly large coupling to photons. In particular,
we determine the number of domain walls per Hubble patch around the time when
they form using numerical simulations and combine this with analytic
expectations about the subsequent dynamics. We show that the strongest
constraint on the decay constant is likely to come from the dark matter ALPs
being produced with large isocurvature fluctuations at small spatial scales. We
also comment on the uncertainties on the dark matter small-scale structure that
might form from these overdensities, in particular pointing out the importance
of quantum pressure in the $N=1$ case.
|
[
{
"created": "Mon, 26 Dec 2022 19:00:00 GMT",
"version": "v1"
}
] |
2023-05-24
|
[
[
"Gorghetto",
"Marco",
""
],
[
"Hardy",
"Edward",
""
]
] |
An axion-like-particle (ALP) in the post-inflationary scenario with domain wall number $N>1$ can be dark matter if the residual $\mathbb{Z}_N$ symmetry has a small explicit breaking. Although we cannot determine the full dynamics of the system reliably, we provide evidence that such an ALP can account for the observed dark matter abundance while having a relatively small decay constant and consequently a possibly large coupling to photons. In particular, we determine the number of domain walls per Hubble patch around the time when they form using numerical simulations and combine this with analytic expectations about the subsequent dynamics. We show that the strongest constraint on the decay constant is likely to come from the dark matter ALPs being produced with large isocurvature fluctuations at small spatial scales. We also comment on the uncertainties on the dark matter small-scale structure that might form from these overdensities, in particular pointing out the importance of quantum pressure in the $N=1$ case.
|
1606.08878
|
Carlos Andr\'es Florez
|
Andr\'es Fl\'orez, Luis Bravo, Alfredo Gurrola, Carlos \'Avila, Manuel
Segura, Paul Sheldon and Will Johns
|
Probing the Stau-Neutralino Coannihilation Region at the LHC with a soft
tau lepton and an ISR jet
|
6 pages including references, 6 figures
|
Phys. Rev. D 94, 073007 (2016)
|
10.1103/PhysRevD.94.073007
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present a feasibility study, to search for dark matter at the LHC, in
events with one soft hadronically decaying tau lepton and missing transverse
energy recoiling against a hard $p_{T}$ jet from initial state radiation. This
methodology allows the search for Supersymmetry in compressed mass spectra
regions, where the mass difference between the lightest neutralino,
$\tilde\chi_1^0$, and the stau (the tau superpartner), $\tilde{\tau}$, is
small. Several theoretical models predict a direct connection between thermal
Bino dark matter and staus within this scenario. We show that compressed
regions, not excluded by ATLAS nor CMS experiments, are opened up with the
increase in experimental sensitivity reached with the proposed methodology. The
requirement of a hard jet from initial state radiation combined with a soft tau
lepton is effective in reducing Standard Model backgrounds, providing expected
significances greater than 3$\sigma$ for $\tilde{\chi}_{1}^{\pm}$ masses up to
300 GeV and $\tilde{\tau}$-$\tilde{\chi}_{1}^{0}$ mass gaps below 25 GeV with
only 30 fb$^{-1}$ of 13 TeV data from the LHC.
|
[
{
"created": "Tue, 28 Jun 2016 20:34:33 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Dec 2016 15:46:24 GMT",
"version": "v2"
}
] |
2016-12-19
|
[
[
"Flórez",
"Andrés",
""
],
[
"Bravo",
"Luis",
""
],
[
"Gurrola",
"Alfredo",
""
],
[
"Ávila",
"Carlos",
""
],
[
"Segura",
"Manuel",
""
],
[
"Sheldon",
"Paul",
""
],
[
"Johns",
"Will",
""
]
] |
We present a feasibility study, to search for dark matter at the LHC, in events with one soft hadronically decaying tau lepton and missing transverse energy recoiling against a hard $p_{T}$ jet from initial state radiation. This methodology allows the search for Supersymmetry in compressed mass spectra regions, where the mass difference between the lightest neutralino, $\tilde\chi_1^0$, and the stau (the tau superpartner), $\tilde{\tau}$, is small. Several theoretical models predict a direct connection between thermal Bino dark matter and staus within this scenario. We show that compressed regions, not excluded by ATLAS nor CMS experiments, are opened up with the increase in experimental sensitivity reached with the proposed methodology. The requirement of a hard jet from initial state radiation combined with a soft tau lepton is effective in reducing Standard Model backgrounds, providing expected significances greater than 3$\sigma$ for $\tilde{\chi}_{1}^{\pm}$ masses up to 300 GeV and $\tilde{\tau}$-$\tilde{\chi}_{1}^{0}$ mass gaps below 25 GeV with only 30 fb$^{-1}$ of 13 TeV data from the LHC.
|
hep-ph/0103092
|
Daniel Litim
|
Daniel F. Litim, Cristina Manuel
|
Transport theory for a two-flavor color superconductor
|
explanations added, typos corrected, to be published by PRL
|
Phys.Rev.Lett. 87 (2001) 052002
|
10.1103/PhysRevLett.87.052002
|
CERN-TH 2001-073
|
hep-ph cond-mat nucl-th
| null |
QCD with two light quark flavors at high baryonic density and low temperature
is a color superconductor. The diquark condensate partially breaks the SU(3)
gauge symmetry down to an SU(2) subgroup. We study thermal fluctuations of the
superconductor for temperatures below the gap. These are described by a simple
transport equation, linked to a quasiparticle behavior of the thermal
excitations of the condensate. When solved in the collisionless limit and close
to equilibrium, it gives rise to the ``hard superconducting loop'' (HSL)
effective theory for the unbroken SU(2) gauge fields with momenta smaller than
the gap. This theory describes Debye screening and Landau damping of the gauge
fields in the presence of the diquark condensate. We also explain how our
effective theory follows to one-loop order from quantum field theory. Our
approach provides a convenient starting point for the computation of transport
coefficients of the two-flavor color superconductor.
|
[
{
"created": "Fri, 9 Mar 2001 19:43:32 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Jun 2001 09:10:33 GMT",
"version": "v2"
}
] |
2009-11-07
|
[
[
"Litim",
"Daniel F.",
""
],
[
"Manuel",
"Cristina",
""
]
] |
QCD with two light quark flavors at high baryonic density and low temperature is a color superconductor. The diquark condensate partially breaks the SU(3) gauge symmetry down to an SU(2) subgroup. We study thermal fluctuations of the superconductor for temperatures below the gap. These are described by a simple transport equation, linked to a quasiparticle behavior of the thermal excitations of the condensate. When solved in the collisionless limit and close to equilibrium, it gives rise to the ``hard superconducting loop'' (HSL) effective theory for the unbroken SU(2) gauge fields with momenta smaller than the gap. This theory describes Debye screening and Landau damping of the gauge fields in the presence of the diquark condensate. We also explain how our effective theory follows to one-loop order from quantum field theory. Our approach provides a convenient starting point for the computation of transport coefficients of the two-flavor color superconductor.
|
1712.03652
|
Osamu Seto
|
Nobuchika Okada and Osamu Seto
|
DAMPE excess from decaying right-handed neutrino dark matter
|
13 pages, 2 figures, the final journal version
| null |
10.1142/S0217732318501572
|
EPHOU-17-016
|
hep-ph astro-ph.HE
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The flux of high-energy cosmic-ray electrons plus positrons recently measured
by the DArk Matter Particle Explorer (DAMPE) exhibits a tentative peak excess
at an energy of around $1.4$ TeV. In this paper, we consider the minimal gauged
$U(1)_{B-L}$ model with a right-handed neutrino (RHN) dark matter (DM) and
interpret the DAMPE peak with a late-time decay of the RHN DM into $e^\pm
W^\mp$. We find that a DM lifetime $\tau_{DM} \sim 10^{28}$ s can fit the DAMPE
peak with a DM mass $m_{DM}=3$ TeV. This favored lifetime is close to the
current bound on it by Fermi-LAT, our decaying RHN DM can be tested once the
measurement of cosmic gamma ray flux is improved. The RHN DM communicates with
the Standard Model particles through the $U(1)_{B-L}$ gauge boson ($Z^\prime$
boson), and its thermal relic abundance is controlled by only three free
parameters: $m_{DM}$, the $U(1)_{B-L}$ gauge coupling ($\alpha_{BL}$), and the
$Z^\prime$ boson mass ($m_{Z^\prime}$). For $m_{DM}=3$ TeV, the rest of the
parameters are restricted to be $m_{Z^\prime}\simeq 6$ TeV and $0.00807 \leq
\alpha_{BL} \leq 0.0149$, in order to reproduce the observed DM relic density
and to avoid the Landau pole for the running $\alpha_{BL}$ below the Planck
scale. This allowed region will be tested by the search for a $Z^\prime$ boson
resonance at the future Large Hadron Collider.
|
[
{
"created": "Mon, 11 Dec 2017 06:20:29 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Dec 2017 05:56:38 GMT",
"version": "v2"
},
{
"created": "Fri, 31 Aug 2018 07:54:01 GMT",
"version": "v3"
}
] |
2018-09-03
|
[
[
"Okada",
"Nobuchika",
""
],
[
"Seto",
"Osamu",
""
]
] |
The flux of high-energy cosmic-ray electrons plus positrons recently measured by the DArk Matter Particle Explorer (DAMPE) exhibits a tentative peak excess at an energy of around $1.4$ TeV. In this paper, we consider the minimal gauged $U(1)_{B-L}$ model with a right-handed neutrino (RHN) dark matter (DM) and interpret the DAMPE peak with a late-time decay of the RHN DM into $e^\pm W^\mp$. We find that a DM lifetime $\tau_{DM} \sim 10^{28}$ s can fit the DAMPE peak with a DM mass $m_{DM}=3$ TeV. This favored lifetime is close to the current bound on it by Fermi-LAT, our decaying RHN DM can be tested once the measurement of cosmic gamma ray flux is improved. The RHN DM communicates with the Standard Model particles through the $U(1)_{B-L}$ gauge boson ($Z^\prime$ boson), and its thermal relic abundance is controlled by only three free parameters: $m_{DM}$, the $U(1)_{B-L}$ gauge coupling ($\alpha_{BL}$), and the $Z^\prime$ boson mass ($m_{Z^\prime}$). For $m_{DM}=3$ TeV, the rest of the parameters are restricted to be $m_{Z^\prime}\simeq 6$ TeV and $0.00807 \leq \alpha_{BL} \leq 0.0149$, in order to reproduce the observed DM relic density and to avoid the Landau pole for the running $\alpha_{BL}$ below the Planck scale. This allowed region will be tested by the search for a $Z^\prime$ boson resonance at the future Large Hadron Collider.
|
hep-ph/0209055
|
Ekaterina Christova
|
S. Kretzer, E. Leader, E. Christova
|
Fragmentation functions and their role in determining the polarized
parton densities
|
6 pages, 2 Figures, a talk presented by E. Leader at the X
International Workshop on Deep Inelastic Scattering (DIS2002) in Krakow,
2002, Poland
|
Acta Phys.Polon. B33 (2002) 3743-3748
| null | null |
hep-ph
| null |
We extract the pion fragmentation functions and their uncertainties from a
judicious choice of e+e- and semi-inclusive DIS data. These are used to study
the error propagation in the extraction of polarized parton densities from
semi-inclusive DIS asymmetries. We conclude that the uncertainties on polarized
PDs have been underestimated in the past.
|
[
{
"created": "Thu, 5 Sep 2002 11:24:07 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Kretzer",
"S.",
""
],
[
"Leader",
"E.",
""
],
[
"Christova",
"E.",
""
]
] |
We extract the pion fragmentation functions and their uncertainties from a judicious choice of e+e- and semi-inclusive DIS data. These are used to study the error propagation in the extraction of polarized parton densities from semi-inclusive DIS asymmetries. We conclude that the uncertainties on polarized PDs have been underestimated in the past.
|
1602.01461
|
John Arrington
|
J. Arrington
|
Comment on "Breakdown of the expansion of finite-size corrections to the
hydrogen Lamb shift in moments of charge distribution"
|
Comment to appear (with Reply) in Physical Review A
|
Phys. Rev. A 93, 026501 (2016)
|
10.1103/PhysRevA.93.026501
| null |
hep-ph nucl-th physics.atom-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In a recent paper, Hagelstein and Pascalutsa examine the error associated
with an expansion of proton structure corrections to the Lamb shift in terms of
moments of the charge distribution. They propose a small modification to a
conventional parameterization of the proton's charge form factor and show that
this can resolve the proton radius puzzle. However, while the size of the
"bump" they add to the form factor is small, it is large compared to the total
proton structure effects in the initial parameterization, yielding a final form
factor that is unphysical. Reducing their modification to the point where the
resulting form factor is physical does not allow for a resolution of the radius
puzzle.
|
[
{
"created": "Tue, 2 Feb 2016 21:12:46 GMT",
"version": "v1"
}
] |
2016-03-09
|
[
[
"Arrington",
"J.",
""
]
] |
In a recent paper, Hagelstein and Pascalutsa examine the error associated with an expansion of proton structure corrections to the Lamb shift in terms of moments of the charge distribution. They propose a small modification to a conventional parameterization of the proton's charge form factor and show that this can resolve the proton radius puzzle. However, while the size of the "bump" they add to the form factor is small, it is large compared to the total proton structure effects in the initial parameterization, yielding a final form factor that is unphysical. Reducing their modification to the point where the resulting form factor is physical does not allow for a resolution of the radius puzzle.
|
0712.4019
|
Hiroaki Sugiyama
|
A.G. Akeroyd (Taiwan, Natl. Cheng Kung U.), Mayumi Aoki (Tokyo U.,
ICRR), Hiroaki Sugiyama (SISSA, Trieste)
|
Probing Majorana Phases and Neutrino Mass Spectrum in the Higgs Triplet
Model at the LHC
|
1+19 pages, 22 figures, typos corrected, references added, version to
appear in Phys. Rev. D
|
Phys.Rev.D77:075010,2008
|
10.1103/PhysRevD.77.075010
|
SISSA-99-2007-EP
|
hep-ph
| null |
Doubly charged Higgs bosons (H^++) are a distinctive signature of the Higgs
Triplet Model of neutrino mass generation. If H^++ is relatively light
(m_{H^++} < 400GeV) it will be produced copiously at the LHC, which could
enable precise measurements of the branching ratios of the decay channels H^++
to l_i l_j. Such branching ratios are determined solely by the neutrino mass
matrix which allows the model to be tested at the LHC. We quantify the
dependence of the leptonic branching ratios on the absolute neutrino mass and
Majorana phases, and present the permitted values for the channels ee, emu and
mumu. It is shown that precise measurements of these three branching ratios are
sufficient to extract information on the neutrino mass spectrum and probe the
presence of CP violation from Majorana phases.
|
[
{
"created": "Mon, 24 Dec 2007 18:44:14 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Mar 2008 13:22:03 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Akeroyd",
"A. G.",
"",
"Taiwan, Natl. Cheng Kung U."
],
[
"Aoki",
"Mayumi",
"",
"Tokyo U.,\n ICRR"
],
[
"Sugiyama",
"Hiroaki",
"",
"SISSA, Trieste"
]
] |
Doubly charged Higgs bosons (H^++) are a distinctive signature of the Higgs Triplet Model of neutrino mass generation. If H^++ is relatively light (m_{H^++} < 400GeV) it will be produced copiously at the LHC, which could enable precise measurements of the branching ratios of the decay channels H^++ to l_i l_j. Such branching ratios are determined solely by the neutrino mass matrix which allows the model to be tested at the LHC. We quantify the dependence of the leptonic branching ratios on the absolute neutrino mass and Majorana phases, and present the permitted values for the channels ee, emu and mumu. It is shown that precise measurements of these three branching ratios are sufficient to extract information on the neutrino mass spectrum and probe the presence of CP violation from Majorana phases.
|
1905.01178
|
A. N. Ivanov
|
A. N. Ivanov, R. H\"ollwieser, N. I. Troitskaya, M. Wellenzohn, Ya. A.
Berdnikov
|
Radiative corrections of order O(alpha E_e/m_N) to Sirlin's radiative
corrections of order O(alpha/pi) to neutron lifetime
|
50 pages, 7 figures. a few typos are corrected. arXiv admin note:
text overlap with arXiv:1805.09702
| null |
10.1103/PhysRevD.99.093006
| null |
hep-ph hep-ex nucl-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We calculate the radiative corrections of order O(alpha E_e/m_N) as
next-to-leading order corrections in the large nucleon mass expansion to
Sirlin's radiative corrections of order O(alpha/pi) to the neutron lifetime.
The calculation is carried out within a quantum field theoretic model of strong
low-energy pion--nucleon interactions described by the linear sigma-model (LsM)
with chiral SU(2)xSU(2) symmetry and electroweak hadron-hadron, hadron-lepton
and lepton-lepton interactions for the electron-lepton family with SU(2)_L x
U(1)_Y symmetry of the Standard Electroweak Model (SEM). Such a quantum field
theoretic model is some kind a hadronized version of the Standard Model (SM).
From a gauge invariant set of the Feynman diagrams with one-photon exchanges we
reproduce Sirlin's radiative corrections of order O(alpha/pi), calculated to
leading order in the large nucleon mass expansion, and calculate
next-to-leading corrections of order O(alpha E_e/m_N). This confirms Sirlin's
confidence level of the radiative corrections O(alpha E_e/m_N). The
contributions of the LsM are taken in the limit of the infinite mass of the
scalar isoscalar sigma-meson. In such a limit the LsM reproduces the results of
the current algebra (Weinberg, Phys. Rev. Lett. {\bf 18}, 188 (1967)) in the
form of effective chiral Lagrangians of pion-nucleon interactions with
non--linear realization of chiral SU(2)xSU(2) symmetry. In such a limit the
L$\sigma$M is also equivalent to Gasser-Leutwyler's chiral quantum field theory
or chiral perturbation theory (ChPT) with chiral SU(2)xSU(2)symmetry and the
exponential parametrization of a pion-field (Ecker, Prog. Part. Nucl. Phys.
{\bf 35}, 1 (1995)).
|
[
{
"created": "Thu, 2 May 2019 15:29:27 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Sep 2021 14:07:39 GMT",
"version": "v2"
}
] |
2021-09-14
|
[
[
"Ivanov",
"A. N.",
""
],
[
"Höllwieser",
"R.",
""
],
[
"Troitskaya",
"N. I.",
""
],
[
"Wellenzohn",
"M.",
""
],
[
"Berdnikov",
"Ya. A.",
""
]
] |
We calculate the radiative corrections of order O(alpha E_e/m_N) as next-to-leading order corrections in the large nucleon mass expansion to Sirlin's radiative corrections of order O(alpha/pi) to the neutron lifetime. The calculation is carried out within a quantum field theoretic model of strong low-energy pion--nucleon interactions described by the linear sigma-model (LsM) with chiral SU(2)xSU(2) symmetry and electroweak hadron-hadron, hadron-lepton and lepton-lepton interactions for the electron-lepton family with SU(2)_L x U(1)_Y symmetry of the Standard Electroweak Model (SEM). Such a quantum field theoretic model is some kind a hadronized version of the Standard Model (SM). From a gauge invariant set of the Feynman diagrams with one-photon exchanges we reproduce Sirlin's radiative corrections of order O(alpha/pi), calculated to leading order in the large nucleon mass expansion, and calculate next-to-leading corrections of order O(alpha E_e/m_N). This confirms Sirlin's confidence level of the radiative corrections O(alpha E_e/m_N). The contributions of the LsM are taken in the limit of the infinite mass of the scalar isoscalar sigma-meson. In such a limit the LsM reproduces the results of the current algebra (Weinberg, Phys. Rev. Lett. {\bf 18}, 188 (1967)) in the form of effective chiral Lagrangians of pion-nucleon interactions with non--linear realization of chiral SU(2)xSU(2) symmetry. In such a limit the L$\sigma$M is also equivalent to Gasser-Leutwyler's chiral quantum field theory or chiral perturbation theory (ChPT) with chiral SU(2)xSU(2)symmetry and the exponential parametrization of a pion-field (Ecker, Prog. Part. Nucl. Phys. {\bf 35}, 1 (1995)).
|
0903.0355
|
Jose Barbon
|
J.L.F. Barbon and J.R. Espinosa
|
On the Naturalness of Higgs Inflation
|
9 pages. Replaced with published version, plus a footnote clarifying
the use of power counting estimates
|
Phys.Rev.D79:081302,2009
|
10.1103/PhysRevD.79.081302
| null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We critically examine the recent claim that the Standard Model Higgs boson
${\cal H}$ could drive inflation in agreement with observations if $|{\cal
H}|^2$ has a strong coupling $\xi\sim 10^4$ to the Ricci curvature scalar. We
first show that the effective theory approach upon which that claim is based
ceases to be valid beyond a cutoff scale $\Lambda=m_p/\xi$, where $m_p$ is the
reduced Planck mass. We then argue that knowing the Higgs potential profile for
the field values relevant for inflation ($|{\cal H}|>m_p/\sqrt{\xi}\gg
\Lambda$) requires knowledge of the ultraviolet completion of the SM beyond
$\Lambda$. In absence of such microscopic theory, the extrapolation of the pure
SM potential beyond $\Lambda$ is unwarranted and the scenario is akin to other
ad-hoc inflaton potentials afflicted with significant fine-tuning. The
appealing naturalness of this minimal proposal is therefore lost.
|
[
{
"created": "Mon, 2 Mar 2009 18:57:02 GMT",
"version": "v1"
},
{
"created": "Wed, 10 Mar 2010 18:54:26 GMT",
"version": "v2"
}
] |
2010-03-12
|
[
[
"Barbon",
"J. L. F.",
""
],
[
"Espinosa",
"J. R.",
""
]
] |
We critically examine the recent claim that the Standard Model Higgs boson ${\cal H}$ could drive inflation in agreement with observations if $|{\cal H}|^2$ has a strong coupling $\xi\sim 10^4$ to the Ricci curvature scalar. We first show that the effective theory approach upon which that claim is based ceases to be valid beyond a cutoff scale $\Lambda=m_p/\xi$, where $m_p$ is the reduced Planck mass. We then argue that knowing the Higgs potential profile for the field values relevant for inflation ($|{\cal H}|>m_p/\sqrt{\xi}\gg \Lambda$) requires knowledge of the ultraviolet completion of the SM beyond $\Lambda$. In absence of such microscopic theory, the extrapolation of the pure SM potential beyond $\Lambda$ is unwarranted and the scenario is akin to other ad-hoc inflaton potentials afflicted with significant fine-tuning. The appealing naturalness of this minimal proposal is therefore lost.
|
2205.06124
|
Wen-long Sang
|
Yu-Dong Zhang, Wen-Long Sang, Hong-Fei Zhang
|
Higher-order QCD corrections to $\Upsilon$ decay into double charmonia
|
13 pages, 2 figures, 3 tables, to match the version accepted for
publication in PRL
| null |
10.1103/PhysRevLett.129.112002
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this work, we study the exclusive decay of $\Upsilon$ into $J/\psi$ in
association with $\eta_c$ ($\chi_{c0,1,2}$). The decay widths for different
helicity configurations are evaluated up to QCD next-to-leading order within
the nonrelativistic QCD framework. We find that the QCD corrections notably
mitigate the renormalization scale dependence of the decay widths for all the
processes. The branching fraction of $\Upsilon\rightarrow J/\psi+\chi_{c1}$ is
obtained as $3.73^{+5.10+0.10}_{-2.06-1.19}\times 10^{-6}$, which agrees well
with the Belle measurement, i.e., ${\rm Br}(\Upsilon\rightarrow
J/\psi+\chi_{c1})=(3.90\pm1.21\pm0.23)\times10^{-6}$. For the other processes,
our results of the branching fractions are compatible with the upper limits
given by the Belle experiments, except for $\Upsilon(2S)\to J/\psi +\chi_{c1}$,
where some tension exists between theory and experiment. Having the polarized
decay widths, we study the $J/\psi$ polarization, which turn out to be
independent of any nonperturbative parameters. Further, according to our
calculation, it is promising to measure all the processes at Super B factory
thanks to the high luminosity.
|
[
{
"created": "Thu, 12 May 2022 14:36:42 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Sep 2022 01:16:38 GMT",
"version": "v2"
}
] |
2022-09-21
|
[
[
"Zhang",
"Yu-Dong",
""
],
[
"Sang",
"Wen-Long",
""
],
[
"Zhang",
"Hong-Fei",
""
]
] |
In this work, we study the exclusive decay of $\Upsilon$ into $J/\psi$ in association with $\eta_c$ ($\chi_{c0,1,2}$). The decay widths for different helicity configurations are evaluated up to QCD next-to-leading order within the nonrelativistic QCD framework. We find that the QCD corrections notably mitigate the renormalization scale dependence of the decay widths for all the processes. The branching fraction of $\Upsilon\rightarrow J/\psi+\chi_{c1}$ is obtained as $3.73^{+5.10+0.10}_{-2.06-1.19}\times 10^{-6}$, which agrees well with the Belle measurement, i.e., ${\rm Br}(\Upsilon\rightarrow J/\psi+\chi_{c1})=(3.90\pm1.21\pm0.23)\times10^{-6}$. For the other processes, our results of the branching fractions are compatible with the upper limits given by the Belle experiments, except for $\Upsilon(2S)\to J/\psi +\chi_{c1}$, where some tension exists between theory and experiment. Having the polarized decay widths, we study the $J/\psi$ polarization, which turn out to be independent of any nonperturbative parameters. Further, according to our calculation, it is promising to measure all the processes at Super B factory thanks to the high luminosity.
|
hep-ph/9705464
|
Warren Perkins
|
Stephen C. Davis, Anne-Christine Davis and Warren B. Perkins
|
Cosmic String Zero Modes and Multiple Phase Transitions
|
15 pages, latex, 1 figure
|
Phys.Lett. B408 (1997) 81-90
|
10.1016/S0370-2693(97)00781-8
|
DAMTP/97-39, SWAT/140
|
hep-ph
| null |
The zero modes and current carrying capability of a cosmic string formed at
one phase transition can be modified at subsequent phase transitions. A new,
generalised index theorem is derived that is applicable to theories with
multiple phase transitions. This enables us to investigate the fate of string
zero modes during sequences of phase transitions in a variety of models.
Depending on the couplings that the breaking introduces, the zero modes may be
destroyed and the superconductivity of the string removed, and thus vortons
dissipate. We discuss the features of the theory that are required to produce
this behaviour and consider the implications of spectral flow.
|
[
{
"created": "Thu, 29 May 1997 17:22:47 GMT",
"version": "v1"
}
] |
2009-10-30
|
[
[
"Davis",
"Stephen C.",
""
],
[
"Davis",
"Anne-Christine",
""
],
[
"Perkins",
"Warren B.",
""
]
] |
The zero modes and current carrying capability of a cosmic string formed at one phase transition can be modified at subsequent phase transitions. A new, generalised index theorem is derived that is applicable to theories with multiple phase transitions. This enables us to investigate the fate of string zero modes during sequences of phase transitions in a variety of models. Depending on the couplings that the breaking introduces, the zero modes may be destroyed and the superconductivity of the string removed, and thus vortons dissipate. We discuss the features of the theory that are required to produce this behaviour and consider the implications of spectral flow.
|
hep-ph/0509368
|
Szymanowski Lech dr
|
B. Pire and L. Szymanowski
|
A QCD analysis of \bar p N -> gamma^* pi and \bar p N -> gamma^* gamma.
Where is the pion in the proton ?
|
4 pages LATEX, 2 .eps figures
|
PoS HEP2005:103,2006
| null | null |
hep-ph nucl-th
| null |
We study the scaling regime of nucleon-anti-nucleon annihilation into a
deeply virtual photon and a photon or meson, \bar p N -> gamma ^* pi, \bar p N
-> gamma ^* gamma, in the forward direction. The leading twist amplitude
factorizes into an antiproton distribution amplitude, a short-distance matrix
element and a long-distance dominated transition distribution amplitude (TDA)
which describes the nucleon to meson or photon transition. The impact
representation of this TDA maps out the transverse locations of the small size
core and the meson or photon cloud inside the proton.
|
[
{
"created": "Fri, 30 Sep 2005 15:30:42 GMT",
"version": "v1"
}
] |
2011-04-11
|
[
[
"Pire",
"B.",
""
],
[
"Szymanowski",
"L.",
""
]
] |
We study the scaling regime of nucleon-anti-nucleon annihilation into a deeply virtual photon and a photon or meson, \bar p N -> gamma ^* pi, \bar p N -> gamma ^* gamma, in the forward direction. The leading twist amplitude factorizes into an antiproton distribution amplitude, a short-distance matrix element and a long-distance dominated transition distribution amplitude (TDA) which describes the nucleon to meson or photon transition. The impact representation of this TDA maps out the transverse locations of the small size core and the meson or photon cloud inside the proton.
|
1605.00670
|
Takeshi Kobayashi
|
Andrea De Simone and Takeshi Kobayashi
|
Cosmological Aspects of Spontaneous Baryogenesis
|
31 pages, 4 figures, v2: published in JCAP
|
JCAP08(2016)052
|
10.1088/1475-7516/2016/08/052
|
SISSA 24/2016/FISI
|
hep-ph astro-ph.CO hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate cosmological aspects of spontaneous baryogenesis driven by a
scalar field, and present general constraints that are independent of the
particle physics model. The relevant constraints are obtained by studying the
backreaction of the produced baryons on the scalar field, the cosmological
expansion history after baryogenesis, and the baryon isocurvature
perturbations. We show that cosmological considerations alone provide powerful
constraints, especially for the minimal scenario with a quadratic scalar
potential. Intriguingly, we find that for a given inflation scale, the other
parameters including the reheat temperature, decoupling temperature of the
baryon violating interactions, and the mass and decay constant of the scalar
are restricted to lie within ranges of at most a few orders of magnitude. We
also discuss possible extensions to the minimal setup, and propose two ideas
for evading constraints on isocurvature perturbations: one is to suppress the
baryon isocurvature with nonquadratic scalar potentials, another is to
compensate the baryon isocurvature with cold dark matter isocurvature by making
the scalar survive until the present.
|
[
{
"created": "Mon, 2 May 2016 20:13:41 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Aug 2016 07:13:49 GMT",
"version": "v2"
}
] |
2016-08-26
|
[
[
"De Simone",
"Andrea",
""
],
[
"Kobayashi",
"Takeshi",
""
]
] |
We investigate cosmological aspects of spontaneous baryogenesis driven by a scalar field, and present general constraints that are independent of the particle physics model. The relevant constraints are obtained by studying the backreaction of the produced baryons on the scalar field, the cosmological expansion history after baryogenesis, and the baryon isocurvature perturbations. We show that cosmological considerations alone provide powerful constraints, especially for the minimal scenario with a quadratic scalar potential. Intriguingly, we find that for a given inflation scale, the other parameters including the reheat temperature, decoupling temperature of the baryon violating interactions, and the mass and decay constant of the scalar are restricted to lie within ranges of at most a few orders of magnitude. We also discuss possible extensions to the minimal setup, and propose two ideas for evading constraints on isocurvature perturbations: one is to suppress the baryon isocurvature with nonquadratic scalar potentials, another is to compensate the baryon isocurvature with cold dark matter isocurvature by making the scalar survive until the present.
|
2007.02936
|
Ole L Trinhammer
|
Ole L. Trinhammer
|
Intrinsic quantum mechanics behind the Standard Model?
|
6 pages, 1 figure, European Physical Society Conference on High
Energy Physics EPS-HEP2019, 10-17 July, 2019 Ghent, Belgium
|
PoS(EPS-HEP2019)616
| null | null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We suggest the gauge groups SU(3), SU(2) and U(1) to share a common origin in
U(3). We take the Lie group U(3) to serve as an intrinsic configuration space
for baryons. A spontaneous symmetry break in the baryonic state selects a U(2)
subgroup for the Higgs mechanism. The Higgs field enters the symmetry break to
relate the strong and electroweak energy scales by exchange of one quantum of
action between the two sectors. This shapes the Higgs potential to fourth
order. Recently intrinsic quantum mechanics has given a suggestion for the
Cabibbo angle from theory (EPL124-2018) and a prediction for the Higgs
couplings to gauge bosons (EPL125-2019). Previously it has given the nucleon
mass and the parton distribution functions for u and d quarks in the proton
(EPL102-2013). It has given a quite accurate equation for the Higgs mass in
closed form (IJMPA30-2015) and an N and Delta spectrum essentially without
missing resonances (arXiv:1109.4732). The intrinsic space is to be
distinguished from an interior space. The intrinsic space is non-spatial, i.e.
no gravity in intrinsic space. The configuration variable is like a generalized
spin variable excited from laboratory space by kinematic generators: momentum,
spin and Laplace-Runge-Lenz operators. The baryon dynamics resides in a
Hamiltonian on U(3) and projects to laboratory space by the momentum form of
the wavefunction. The momentum form generates conjugate quark and gluon fields.
Local gauge invariance in laboratory space follows from unitarity of the
configuration variable and left invariance of the coordinate fields on the
intrinsic space. Future work should aim to invoke leptons in the second and
third generations and quarks in the third.
|
[
{
"created": "Mon, 6 Jul 2020 08:00:56 GMT",
"version": "v1"
}
] |
2020-07-08
|
[
[
"Trinhammer",
"Ole L.",
""
]
] |
We suggest the gauge groups SU(3), SU(2) and U(1) to share a common origin in U(3). We take the Lie group U(3) to serve as an intrinsic configuration space for baryons. A spontaneous symmetry break in the baryonic state selects a U(2) subgroup for the Higgs mechanism. The Higgs field enters the symmetry break to relate the strong and electroweak energy scales by exchange of one quantum of action between the two sectors. This shapes the Higgs potential to fourth order. Recently intrinsic quantum mechanics has given a suggestion for the Cabibbo angle from theory (EPL124-2018) and a prediction for the Higgs couplings to gauge bosons (EPL125-2019). Previously it has given the nucleon mass and the parton distribution functions for u and d quarks in the proton (EPL102-2013). It has given a quite accurate equation for the Higgs mass in closed form (IJMPA30-2015) and an N and Delta spectrum essentially without missing resonances (arXiv:1109.4732). The intrinsic space is to be distinguished from an interior space. The intrinsic space is non-spatial, i.e. no gravity in intrinsic space. The configuration variable is like a generalized spin variable excited from laboratory space by kinematic generators: momentum, spin and Laplace-Runge-Lenz operators. The baryon dynamics resides in a Hamiltonian on U(3) and projects to laboratory space by the momentum form of the wavefunction. The momentum form generates conjugate quark and gluon fields. Local gauge invariance in laboratory space follows from unitarity of the configuration variable and left invariance of the coordinate fields on the intrinsic space. Future work should aim to invoke leptons in the second and third generations and quarks in the third.
|
hep-ph/9911261
| null |
Harry J. Lipkin (Weizmann Institute of Science, Tel Aviv University,
University of Connecticut)
|
Theoretical Analysis of Static Hyperon Data for HYPERON99
|
16 pages
| null | null |
TAUP 2601-99. WIS-99/35/Nov-DPP
|
hep-ph
| null |
We consider all hyperon data relevant to spin and flavor structure of
hyperons. In addition to masses and magnetic moments considered as static
properties in Hyperon99 we include also relevant data from hyperon decays and
spin structure determined from deep inelastic scattering. Any theoretical model
for the hyperons with parameters to be determined from experiment should use
input from all these data. Of particular interest are new data from $\Xi^o$
decay and the polarixation of $\Lambda's$ produced in Z^o decays and deep
inelastic scattering.
|
[
{
"created": "Fri, 5 Nov 1999 21:19:07 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Lipkin",
"Harry J.",
"",
"Weizmann Institute of Science, Tel Aviv University,\n University of Connecticut"
]
] |
We consider all hyperon data relevant to spin and flavor structure of hyperons. In addition to masses and magnetic moments considered as static properties in Hyperon99 we include also relevant data from hyperon decays and spin structure determined from deep inelastic scattering. Any theoretical model for the hyperons with parameters to be determined from experiment should use input from all these data. Of particular interest are new data from $\Xi^o$ decay and the polarixation of $\Lambda's$ produced in Z^o decays and deep inelastic scattering.
|
0908.0857
|
Dean Horton
|
D. Horton, G. G. Ross
|
Naturalness and Focus Points with Non-Universal Gaugino Masses
|
31 pages, 21 figures. Version accepted for publication in Nuclear
Physics B
|
Nucl.Phys.B830:221-247,2010
|
10.1016/j.nuclphysb.2009.12.031
|
OUTP-0919P
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Relations between the gaugino masses have been shown to alleviate the degree
of fine-tuning in the MSSM. In this paper we consider specific models of
supersymmetry breaking with gravity mediation and demonstrate that within both
GUT and string constructions it is possible to generate these relations in a
natural way. We have numerically studied the degree of fine-tuning in these
models, including one-loop corrections, and have found regions of parameter
space that can satisfy all known collider constraints with fine-tunings less
than 20%. We discuss some of the phenomenological features of these models
within the regions of reduced fine-tuning.
|
[
{
"created": "Thu, 6 Aug 2009 12:55:29 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Jan 2010 11:57:58 GMT",
"version": "v2"
}
] |
2010-02-03
|
[
[
"Horton",
"D.",
""
],
[
"Ross",
"G. G.",
""
]
] |
Relations between the gaugino masses have been shown to alleviate the degree of fine-tuning in the MSSM. In this paper we consider specific models of supersymmetry breaking with gravity mediation and demonstrate that within both GUT and string constructions it is possible to generate these relations in a natural way. We have numerically studied the degree of fine-tuning in these models, including one-loop corrections, and have found regions of parameter space that can satisfy all known collider constraints with fine-tunings less than 20%. We discuss some of the phenomenological features of these models within the regions of reduced fine-tuning.
|
1704.04699
|
Roman Pasechnik
|
Victor P. Goncalves, Boris Kopeliovich, Jan Nemchik, Roman Pasechnik
and Irina Potashnikova
|
Heavy flavor production in high-energy $pp$ collisions: color dipole
description
|
22 pages, 9 figures
|
Phys. Rev. D 96, 014010 (2017)
|
10.1103/PhysRevD.96.014010
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present a detailed study of open heavy flavor production in high-energy
$pp$ collisions at the LHC in the color dipole framework. The transverse
momentum distributions of produced $b$-jets, accounting for the jet energy
loss, as well as produced open charm $D$ and bottom $B$ mesons in distinct
rapidity intervals relevant for LHC measurements are computed. The dipole model
results for the differential $b$-jet production cross section are compared to
the recent ATLAS and CMS data while the results for $D$ and $B$ mesons
production cross sections -- to the corresponding LHCb data. Several models for
the phenomenological dipole cross section have been employed to estimate
theoretical uncertainties of the dipole model predictions. We demonstrate that
the primordial transverse momentum distribution of the projectile gluon
significantly affects the meson spectra at low transverse momenta and
contributes to the largest uncertainty of the dipole model predictions.
|
[
{
"created": "Sat, 15 Apr 2017 23:41:54 GMT",
"version": "v1"
}
] |
2017-07-19
|
[
[
"Goncalves",
"Victor P.",
""
],
[
"Kopeliovich",
"Boris",
""
],
[
"Nemchik",
"Jan",
""
],
[
"Pasechnik",
"Roman",
""
],
[
"Potashnikova",
"Irina",
""
]
] |
We present a detailed study of open heavy flavor production in high-energy $pp$ collisions at the LHC in the color dipole framework. The transverse momentum distributions of produced $b$-jets, accounting for the jet energy loss, as well as produced open charm $D$ and bottom $B$ mesons in distinct rapidity intervals relevant for LHC measurements are computed. The dipole model results for the differential $b$-jet production cross section are compared to the recent ATLAS and CMS data while the results for $D$ and $B$ mesons production cross sections -- to the corresponding LHCb data. Several models for the phenomenological dipole cross section have been employed to estimate theoretical uncertainties of the dipole model predictions. We demonstrate that the primordial transverse momentum distribution of the projectile gluon significantly affects the meson spectra at low transverse momenta and contributes to the largest uncertainty of the dipole model predictions.
|
hep-ph/9512316
| null |
E.Gotsman (Tel-Aviv.Un.), E.M.Levin (CBPF/St.Petersburg) and U.Maor
(Tel-Aviv.Un.)
|
A Screened BFKL Interpretation of $F_2$ in the Exceedingly Small x Limit
|
11 pages,3 pictures in eps files
|
Phys.Lett. B379 (1996) 186-194
|
10.1016/0370-2693(96)00436-4
|
TAUP 2307-95, CBPF NF-085-95, UCI 95-34
|
hep-ph
| null |
In this letter we show that the behaviour of $F_{2}$, at very small $x_B$,
agrees with the behaviour expected from the BFKL evolution equation, when
screening corrections are included. We obtain a description which is consistent
with the data, however, we require the screening corrections to be relatively
large (about a quarter of the total DIS cross section). The relation between
the screening corrections and the diffractive DIS cross section is discussed.
|
[
{
"created": "Thu, 14 Dec 1995 19:10:59 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Gotsman",
"E.",
"",
"Tel-Aviv.Un."
],
[
"Levin",
"E. M.",
"",
"CBPF/St.Petersburg"
],
[
"Maor",
"U.",
"",
"Tel-Aviv.Un."
]
] |
In this letter we show that the behaviour of $F_{2}$, at very small $x_B$, agrees with the behaviour expected from the BFKL evolution equation, when screening corrections are included. We obtain a description which is consistent with the data, however, we require the screening corrections to be relatively large (about a quarter of the total DIS cross section). The relation between the screening corrections and the diffractive DIS cross section is discussed.
|
2109.02531
|
Rui-Lin Zhu
|
Huimin Ren, Fan Wu, Ruilin Zhu
|
Hadronic molecule interpretation of $T^+_{cc}$ and its beauty-partners
|
7 pages, 1 figure, and 1 table; the theoretical uncertainty is
discussed
|
Adv.High Energy Phys. 2022, (2022) 9103031
|
10.1155/2022/9103031
| null |
hep-ph hep-ex
|
http://creativecommons.org/licenses/by/4.0/
|
Motivated by the latest discovery of a new tetraquark $T_{cc}^+$ with two
charm quarks and two light antiquarks by LHCb Collaboration, we investigated
the $DD^*$ hadronic molecule interpretation of $T_{cc}^+$. By calculation, the
mass and the decay width of this new structure $T_{cc}^+$ can be understood in
one-meson exchange potential model. The binding energies for these $DD^*$
hadronic molecules with $J^P=1^+$ are around $1MeV$. Besides, we also studied
the possible beauty-partners $T_{bb}(10598)$ of hadronic molecule $T^+_{cc}$,
which may be feasible in future LHCb experiments.
|
[
{
"created": "Mon, 6 Sep 2021 15:14:19 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Sep 2021 13:36:14 GMT",
"version": "v2"
},
{
"created": "Tue, 11 Jan 2022 14:22:56 GMT",
"version": "v3"
}
] |
2022-03-08
|
[
[
"Ren",
"Huimin",
""
],
[
"Wu",
"Fan",
""
],
[
"Zhu",
"Ruilin",
""
]
] |
Motivated by the latest discovery of a new tetraquark $T_{cc}^+$ with two charm quarks and two light antiquarks by LHCb Collaboration, we investigated the $DD^*$ hadronic molecule interpretation of $T_{cc}^+$. By calculation, the mass and the decay width of this new structure $T_{cc}^+$ can be understood in one-meson exchange potential model. The binding energies for these $DD^*$ hadronic molecules with $J^P=1^+$ are around $1MeV$. Besides, we also studied the possible beauty-partners $T_{bb}(10598)$ of hadronic molecule $T^+_{cc}$, which may be feasible in future LHCb experiments.
|
hep-ph/9209290
|
Aldo Deandrea
|
R. Casalbuoni, A. Deandrea, S. De Curtis, N. Di Bartolomeo, D.
Dominici, F. Feruglio, R. Gatto
|
The Extended Bess Model: Bounds from Precision Electroweak Measurements
|
LaTeX (style article), 28 pages, 7 figures, UGVA-DPT 1992/07-778, v2
only updates the original broken TeX file
|
Nucl.Phys. B409 (1993) 257-289
|
10.1016/0550-3213(93)90580-I
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present an effective Lagrangian parameterization describing scalar,
vector, and axial-vector bound states, originating from a strong breaking of
the electroweak symmetry, based on the global symmetry $SU(N)_L\otimes
SU(N)_R$. In this approach vector and axial-vector bound states are gauge
bosons associated to a hidden $SU(N)_L\otimes SU(N)_R$ symmetry. After the
gauging of the electroweak symmetry, the corrections to the self-energies of
the standard model gauge bosons are calculated and bounds on the parameter
space of the model arising from precision measurements are studied. The
self-energy corrections arise from spin 1 mixings, pseudogoldstones loops,
pseudogoldstone-spin 1 loops, and tadpole terms. The one-loop terms tend to
decrease both isospin conserving and isospin violating corrections. Careful
calculation for standard $SU(8)$ QCD-scaled technicolor shows that strictly
this model (which has however serious theoretical difficulties on his own) is
still marginally allowed at present experimental precision.
|
[
{
"created": "Tue, 29 Sep 1992 09:26:00 GMT",
"version": "v1"
},
{
"created": "Fri, 15 May 2015 14:35:37 GMT",
"version": "v2"
}
] |
2015-05-18
|
[
[
"Casalbuoni",
"R.",
""
],
[
"Deandrea",
"A.",
""
],
[
"De Curtis",
"S.",
""
],
[
"Di Bartolomeo",
"N.",
""
],
[
"Dominici",
"D.",
""
],
[
"Feruglio",
"F.",
""
],
[
"Gatto",
"R.",
""
]
] |
We present an effective Lagrangian parameterization describing scalar, vector, and axial-vector bound states, originating from a strong breaking of the electroweak symmetry, based on the global symmetry $SU(N)_L\otimes SU(N)_R$. In this approach vector and axial-vector bound states are gauge bosons associated to a hidden $SU(N)_L\otimes SU(N)_R$ symmetry. After the gauging of the electroweak symmetry, the corrections to the self-energies of the standard model gauge bosons are calculated and bounds on the parameter space of the model arising from precision measurements are studied. The self-energy corrections arise from spin 1 mixings, pseudogoldstones loops, pseudogoldstone-spin 1 loops, and tadpole terms. The one-loop terms tend to decrease both isospin conserving and isospin violating corrections. Careful calculation for standard $SU(8)$ QCD-scaled technicolor shows that strictly this model (which has however serious theoretical difficulties on his own) is still marginally allowed at present experimental precision.
|
1301.2989
|
Fen Zuo
|
Fen Zuo
|
Holography, chiral Lagrangian and form factor relations
|
Typo corrected; 8 pages, 1 figure; Proceedings of the Xth Quark
Confinement and the Hadron Spectrum, October 8-12, 2012, TUM Campus Garching,
Munich, Germany
| null | null |
BARI-TH-2013-667
|
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We perform a detailed study of mesonic properties in a class of holographic
models of QCD, which is described by the Yang-Mills plus Chern-Simons action.
By decomposing the 5 dimensional gauge field into resonances and integrating
out the massive ones, we reproduce the Chiral Perturbative Theory Lagrangian up
to ${\cal O}(p^6)$ and obtain all the relevant low energy constants (LECs). The
numerical predictions of the LECs show minor model dependence, and agree
reasonably with the determinations from other approaches. Interestingly,
various model-independent relations appear among them. Some of these relations
are found to be the large-distance limits of universal relations between form
factors of the anomalous and even-parity sectors of QCD.
|
[
{
"created": "Mon, 14 Jan 2013 14:39:10 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Jan 2013 09:48:46 GMT",
"version": "v2"
}
] |
2013-01-17
|
[
[
"Zuo",
"Fen",
""
]
] |
We perform a detailed study of mesonic properties in a class of holographic models of QCD, which is described by the Yang-Mills plus Chern-Simons action. By decomposing the 5 dimensional gauge field into resonances and integrating out the massive ones, we reproduce the Chiral Perturbative Theory Lagrangian up to ${\cal O}(p^6)$ and obtain all the relevant low energy constants (LECs). The numerical predictions of the LECs show minor model dependence, and agree reasonably with the determinations from other approaches. Interestingly, various model-independent relations appear among them. Some of these relations are found to be the large-distance limits of universal relations between form factors of the anomalous and even-parity sectors of QCD.
|
1406.1798
|
Juan Antonio Aguilar-Saavedra
|
J.A. Aguilar-Saavedra, D. Amidei, A. Juste, M. Perez-Victoria
|
Asymmetries in top quark pair production at hadron colliders
|
RevTeX 40 pages. Final version to be published in Reviews of Modern
Physics, with several additions
| null |
10.1103/RevModPhys.87.421
|
CERN-PH-TH-2014-101
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We review the asymmetries in top quark pair production at the Tevatron and
the LHC. We summarize the experimental measurements and the interpretations of
a possible excess in terms of new physics. We also review other top quark
properties-emphasizing effects related to the $t \bar t$ asymmetries-as well as
other collider signals.
|
[
{
"created": "Fri, 6 Jun 2014 20:00:01 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Jun 2014 15:12:38 GMT",
"version": "v2"
},
{
"created": "Thu, 5 Mar 2015 18:23:53 GMT",
"version": "v3"
}
] |
2015-06-11
|
[
[
"Aguilar-Saavedra",
"J. A.",
""
],
[
"Amidei",
"D.",
""
],
[
"Juste",
"A.",
""
],
[
"Perez-Victoria",
"M.",
""
]
] |
We review the asymmetries in top quark pair production at the Tevatron and the LHC. We summarize the experimental measurements and the interpretations of a possible excess in terms of new physics. We also review other top quark properties-emphasizing effects related to the $t \bar t$ asymmetries-as well as other collider signals.
|
1407.4108
|
Mirco Cannoni
|
Mirco Cannoni
|
Exact theory of freeze out
|
10 pages, 2 figure: V3 similar to the published version in EPJ C
|
Eur. Phys. J. C 75, 106 (2015)
|
10.1140/epjc/s10052-015-3328-6
| null |
hep-ph astro-ph.CO gr-qc hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We show that the standard theory of thermal production and chemical
decoupling of WIMPs is incomplete. The hypothesis that WIMPs are produced and
decouple from a thermal bath implies that the rate equation the bath particles
interacting with the WIMPs is an algebraic equation that constraints the actual
WIMPs abundance to have a precise analytical form down to the temperature
$x_\ast=m_\chi /T_\ast$. The point $x_\ast$, which coincides with the
stationary point of the equation for the quantity $\Delta= Y-Y_0$, is where the
maximum departure of the WIMPs abundance $Y$ from the thermal value $Y_0$ is
reached. For each mass $m_\chi$ and total annihilation cross section $\langle
\sigma_\text{ann}v_\text{r}\rangle$, the temperature $x_\ast$ and the actual
WIMPs abundance $Y(x_\ast)$ are exactly known. This value provides the true
initial condition for the usual differential equation that have to be
integrated in the interval $x\ge x_\ast$. The matching of the two abundances at
$x_\ast$ is continuous and differentiable. The dependence of the present relic
abundance on the abundance at an intermediate temperature is an exact result.
The exact theory suggests a new analytical approximation that furnishes the
relic abundance accurate at the level of $1\%-2\%$ in the case of $S$-wave and
$P$-wave scattering cross sections. We conclude the paper studying the
evolution of the WIMPs chemical potential and the entropy production using
methods of non equilibrium thermodynamics.
|
[
{
"created": "Tue, 15 Jul 2014 19:41:56 GMT",
"version": "v1"
},
{
"created": "Thu, 11 Dec 2014 18:02:14 GMT",
"version": "v2"
},
{
"created": "Thu, 5 Mar 2015 16:26:58 GMT",
"version": "v3"
}
] |
2015-03-06
|
[
[
"Cannoni",
"Mirco",
""
]
] |
We show that the standard theory of thermal production and chemical decoupling of WIMPs is incomplete. The hypothesis that WIMPs are produced and decouple from a thermal bath implies that the rate equation the bath particles interacting with the WIMPs is an algebraic equation that constraints the actual WIMPs abundance to have a precise analytical form down to the temperature $x_\ast=m_\chi /T_\ast$. The point $x_\ast$, which coincides with the stationary point of the equation for the quantity $\Delta= Y-Y_0$, is where the maximum departure of the WIMPs abundance $Y$ from the thermal value $Y_0$ is reached. For each mass $m_\chi$ and total annihilation cross section $\langle \sigma_\text{ann}v_\text{r}\rangle$, the temperature $x_\ast$ and the actual WIMPs abundance $Y(x_\ast)$ are exactly known. This value provides the true initial condition for the usual differential equation that have to be integrated in the interval $x\ge x_\ast$. The matching of the two abundances at $x_\ast$ is continuous and differentiable. The dependence of the present relic abundance on the abundance at an intermediate temperature is an exact result. The exact theory suggests a new analytical approximation that furnishes the relic abundance accurate at the level of $1\%-2\%$ in the case of $S$-wave and $P$-wave scattering cross sections. We conclude the paper studying the evolution of the WIMPs chemical potential and the entropy production using methods of non equilibrium thermodynamics.
|
0805.0418
|
Eugene Levin
|
E. Gotsman, E.Levin and U.Maor
|
A Study of Soft Interactions at Ultra High Energies
|
6pp. 3 figures
|
Braz.J.Phys.38:431-436,2008
| null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present and discuss our recent study of an eikonal two channel model, in
which we reproduce the soft total, integrated elastic and diffractive cross
sections, and the corresponding forward differential slopes in the ISR-Tevatron
energy range. Our study is extended to provide predictions at the LHC and
Cosmic Rays ene$ These are utilized to assess the role of unitarity at ultra
high energies, as well as predict the implied survival probability of exclusive
diffractiv$ central production of a light Higgs. Our approach is critically
examined so as to estimate the margins of error of the calculated survival
probability for diffractive Higgs production
|
[
{
"created": "Sun, 4 May 2008 14:33:31 GMT",
"version": "v1"
}
] |
2008-12-18
|
[
[
"Gotsman",
"E.",
""
],
[
"Levin",
"E.",
""
],
[
"Maor",
"U.",
""
]
] |
We present and discuss our recent study of an eikonal two channel model, in which we reproduce the soft total, integrated elastic and diffractive cross sections, and the corresponding forward differential slopes in the ISR-Tevatron energy range. Our study is extended to provide predictions at the LHC and Cosmic Rays ene$ These are utilized to assess the role of unitarity at ultra high energies, as well as predict the implied survival probability of exclusive diffractiv$ central production of a light Higgs. Our approach is critically examined so as to estimate the margins of error of the calculated survival probability for diffractive Higgs production
|
1805.11003
|
Carlos Arg\"uelles Delgado
|
Carlos A. Arg\"uelles, Sergio Palomares-Ruiz, Austin Schneider, Logan
Wille, Tianlu Yuan
|
Unified atmospheric neutrino passing fractions for large-scale neutrino
telescopes
|
32 pages, 14 figures, 8 tables, and code available at
https://github.com/tianluyuan/nuVeto/
| null |
10.1088/1475-7516/2018/07/047
|
IFIC/18-24
|
hep-ph astro-ph.HE hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The atmospheric neutrino passing fraction, or self-veto, is defined as the
probability for an atmospheric neutrino not to be accompanied by a detectable
muon from the same cosmic-ray air shower. Building upon previous work, we
propose a redefinition of the passing fractions by unifying the treatment for
muon and electron neutrinos. Several approximations have also been removed.
This enables performing detailed estimations of the uncertainties in the
passing fractions from several inputs: muon losses, cosmic-ray spectrum,
hadronic-interaction models and atmosphere-density profiles. We also study the
passing fractions under variations of the detector configuration: depth,
surrounding medium and muon veto trigger probability. The calculation exhibits
excellent agreement with passing fractions obtained from Monte Carlo
simulations. Finally, we provide a general software framework to implement this
veto technique for all large-scale neutrino observatories.
|
[
{
"created": "Mon, 28 May 2018 16:04:37 GMT",
"version": "v1"
},
{
"created": "Tue, 12 Jun 2018 23:43:00 GMT",
"version": "v2"
}
] |
2018-08-08
|
[
[
"Argüelles",
"Carlos A.",
""
],
[
"Palomares-Ruiz",
"Sergio",
""
],
[
"Schneider",
"Austin",
""
],
[
"Wille",
"Logan",
""
],
[
"Yuan",
"Tianlu",
""
]
] |
The atmospheric neutrino passing fraction, or self-veto, is defined as the probability for an atmospheric neutrino not to be accompanied by a detectable muon from the same cosmic-ray air shower. Building upon previous work, we propose a redefinition of the passing fractions by unifying the treatment for muon and electron neutrinos. Several approximations have also been removed. This enables performing detailed estimations of the uncertainties in the passing fractions from several inputs: muon losses, cosmic-ray spectrum, hadronic-interaction models and atmosphere-density profiles. We also study the passing fractions under variations of the detector configuration: depth, surrounding medium and muon veto trigger probability. The calculation exhibits excellent agreement with passing fractions obtained from Monte Carlo simulations. Finally, we provide a general software framework to implement this veto technique for all large-scale neutrino observatories.
|
1808.01643
|
Hiromasa Takaura
|
Hiromasa Takaura, Takashi Kaneko, Yuichiro Kiyo, Yukinari Sumino
|
Determination of $\alpha_s$ from static QCD potential: OPE with
renormalon subtraction and lattice QCD
|
Version to appear in JHEP, Supplementary analyses added in Appendix
F; other modifications are minor, 42 pages
| null | null |
KYUSHU-HET-187, KEK-CP-368, TU-1070
|
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We determine the strong coupling constant $\alpha_s$ from the static QCD
potential by matching a theoretical calculation with a lattice QCD computation.
We employ a new theoretical formulation based on the operator product
expansion, in which renormalons are subtracted from the leading Wilson
coefficient. We remove not only the leading renormalon uncertainty of
$\mathcal{O}(\Lambda_{\rm QCD})$ but also the first $r$-dependent uncertainty
of $\mathcal{O}(\Lambda_{\rm QCD}^3 r^2)$. The theoretical prediction for the
potential turns out to be valid at the static color charge distance
$\Lambda_{\rm \overline{MS}} r \lesssim 0.8$ ($r \lesssim 0.4$ fm), which is
significantly larger than ordinary perturbation theory. With lattice data down
to $\Lambda_{\rm \overline{MS}} r \sim 0.09$ ($r \sim 0.05$ fm), we perform the
matching in a wide region of $r$, which has been difficult in previous
determinations of $\alpha_s$ from the potential. Our final result is
$\alpha_s(M_Z^2) = 0.1179^{+0.0015}_{-0.0014}$ with 1.3 % accuracy. The
dominant uncertainty comes from higher order corrections to the perturbative
prediction and can be straightforwardly reduced by simulating finer lattices.
|
[
{
"created": "Sun, 5 Aug 2018 16:20:26 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Apr 2019 04:29:47 GMT",
"version": "v2"
}
] |
2019-05-02
|
[
[
"Takaura",
"Hiromasa",
""
],
[
"Kaneko",
"Takashi",
""
],
[
"Kiyo",
"Yuichiro",
""
],
[
"Sumino",
"Yukinari",
""
]
] |
We determine the strong coupling constant $\alpha_s$ from the static QCD potential by matching a theoretical calculation with a lattice QCD computation. We employ a new theoretical formulation based on the operator product expansion, in which renormalons are subtracted from the leading Wilson coefficient. We remove not only the leading renormalon uncertainty of $\mathcal{O}(\Lambda_{\rm QCD})$ but also the first $r$-dependent uncertainty of $\mathcal{O}(\Lambda_{\rm QCD}^3 r^2)$. The theoretical prediction for the potential turns out to be valid at the static color charge distance $\Lambda_{\rm \overline{MS}} r \lesssim 0.8$ ($r \lesssim 0.4$ fm), which is significantly larger than ordinary perturbation theory. With lattice data down to $\Lambda_{\rm \overline{MS}} r \sim 0.09$ ($r \sim 0.05$ fm), we perform the matching in a wide region of $r$, which has been difficult in previous determinations of $\alpha_s$ from the potential. Our final result is $\alpha_s(M_Z^2) = 0.1179^{+0.0015}_{-0.0014}$ with 1.3 % accuracy. The dominant uncertainty comes from higher order corrections to the perturbative prediction and can be straightforwardly reduced by simulating finer lattices.
|
1201.1249
|
Marek G\'o\'zd\'z
|
Marek G\'o\'zd\'z and Marek Rogatko
|
Neutrino Oscillations in Strong Gravitational Fields
|
I've decided to move the collection of my papers to arXiv for easier
access. Proceedings of the Nuclear Physics Workshop in Kazimierz Dolny,
Poland, 2010
|
Int. J. Mod. Phys. E 20 (2011) 507
|
10.1142/S0218301311017922
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Neutrinos do oscillate, which up to our best knowledge implies that they are
massive particles. As such, neutrinos should interact with gravitational
fields. As their masses are tiny, the gravitational fields must be extremely
strong. In this paper we study the influence of black holes described by
non-trivial topologies on the neutrino oscillations. We present approximate
analytical and numerical solutions of certain specific cases.
|
[
{
"created": "Thu, 5 Jan 2012 18:20:03 GMT",
"version": "v1"
}
] |
2015-06-03
|
[
[
"Góźdź",
"Marek",
""
],
[
"Rogatko",
"Marek",
""
]
] |
Neutrinos do oscillate, which up to our best knowledge implies that they are massive particles. As such, neutrinos should interact with gravitational fields. As their masses are tiny, the gravitational fields must be extremely strong. In this paper we study the influence of black holes described by non-trivial topologies on the neutrino oscillations. We present approximate analytical and numerical solutions of certain specific cases.
|
hep-ph/9807350
| null |
C. Hamzaoui, M. Pospelov and M. Toharia
|
Higgs-mediated FCNC in Supersymmetic Models with Large $\tan\beta$
|
15 pages, latex, 3 figures
|
Phys.Rev. D59 (1999) 095005
|
10.1103/PhysRevD.59.095005
| null |
hep-ph
| null |
In the supersymmetric models with nontrivial flavour structure in the
soft-breaking sector the exchange of neutral Higgses mediates $\Delta F=2$
transitions. This mechanism is studied for $\Delta S, \Delta B=2$ processes and
for a generic form of the soft-breaking terms. We find that Higgs-mediated FCNC
amplitudes increase very rapidly with $\tan\beta$ and can exceed $SUSY$ box
contribution by up to two orders of magnitude when $\tan\beta\sim m_t/m_b$.
|
[
{
"created": "Mon, 13 Jul 1998 04:36:25 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Hamzaoui",
"C.",
""
],
[
"Pospelov",
"M.",
""
],
[
"Toharia",
"M.",
""
]
] |
In the supersymmetric models with nontrivial flavour structure in the soft-breaking sector the exchange of neutral Higgses mediates $\Delta F=2$ transitions. This mechanism is studied for $\Delta S, \Delta B=2$ processes and for a generic form of the soft-breaking terms. We find that Higgs-mediated FCNC amplitudes increase very rapidly with $\tan\beta$ and can exceed $SUSY$ box contribution by up to two orders of magnitude when $\tan\beta\sim m_t/m_b$.
|
0708.2580
|
Leonard Gamberg
|
Leonard P. Gamberg, Gary R. Goldstein and Marc Schlegel
|
Flavor Dependence of T-odd PDFs
|
To appear in the proceedings of 15th International Workshop on
Deep-Inelastic Scattering and Related Subjects (DIS2007), Munich, Germany,
16-20 Apr 2007
| null | null | null |
hep-ph
| null |
The flavor dependence of the naive time reversal odd (``T-odd'') parton
distributions for $u$- and $d$-quarks are explored in the spectator model. The
flavor dependence of $h_{1}^{\perp}$ is of significance for the analysis of the
azimuthal $\cos(2\phi)$ asymmetries in unpolarized SIDIS and DY-processes, as
well as for the overall physical understanding of the distribution of
transversely polarized quarks in unpolarized nucleons. As a by-product of the
formalism, we calculate the chiral-odd but ``T-even'' function $h_{1L}^{\perp}$
which enables us to present a prediction for the single spin asymmetry
$A_{UL}^{\sin(2\phi)}$ for a longitudinally polarized target in SIDIS.
|
[
{
"created": "Mon, 20 Aug 2007 03:25:00 GMT",
"version": "v1"
}
] |
2007-08-21
|
[
[
"Gamberg",
"Leonard P.",
""
],
[
"Goldstein",
"Gary R.",
""
],
[
"Schlegel",
"Marc",
""
]
] |
The flavor dependence of the naive time reversal odd (``T-odd'') parton distributions for $u$- and $d$-quarks are explored in the spectator model. The flavor dependence of $h_{1}^{\perp}$ is of significance for the analysis of the azimuthal $\cos(2\phi)$ asymmetries in unpolarized SIDIS and DY-processes, as well as for the overall physical understanding of the distribution of transversely polarized quarks in unpolarized nucleons. As a by-product of the formalism, we calculate the chiral-odd but ``T-even'' function $h_{1L}^{\perp}$ which enables us to present a prediction for the single spin asymmetry $A_{UL}^{\sin(2\phi)}$ for a longitudinally polarized target in SIDIS.
|
1909.02460
|
Alexei Pivovarov A.
|
Stefan Groote, Thomas Mannel and Alexei A. Pivovarov
|
Hadronic contributions to the muon anomalous moment
|
18 pages, 2 figure
| null | null |
SI-HEP-2019-14, SFB-257-P3H-19-037
|
hep-ph hep-ex hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss the hadronic contributions to the muon anomalous magnetic moment.
They are dominated by light quark contributions which are constrained by the
mechanism of chiral symmetry breaking. Using the leading order result based on
$e^+ e^-$ scattering data, we show that the next-to-leading order contributions
in the fine structure constant $\alpha$ can be reliably calculated. Extending
this idea to the hadronic four-point function we give a prediction for the
light-by-light contribution.
|
[
{
"created": "Thu, 5 Sep 2019 14:46:28 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Oct 2019 13:23:53 GMT",
"version": "v2"
}
] |
2019-10-29
|
[
[
"Groote",
"Stefan",
""
],
[
"Mannel",
"Thomas",
""
],
[
"Pivovarov",
"Alexei A.",
""
]
] |
We discuss the hadronic contributions to the muon anomalous magnetic moment. They are dominated by light quark contributions which are constrained by the mechanism of chiral symmetry breaking. Using the leading order result based on $e^+ e^-$ scattering data, we show that the next-to-leading order contributions in the fine structure constant $\alpha$ can be reliably calculated. Extending this idea to the hadronic four-point function we give a prediction for the light-by-light contribution.
|
hep-ph/9907573
|
Gary Goldstein
|
Gary R. Goldstein (Tufts University)
|
Polarization of inclusively produced $\Lambda_c$ in a QCD based hybrid
model
|
12 pages Latex2e including 4 PostScript figures
| null | null |
TUFTS TH-99-G02
|
hep-ph
| null |
A hybrid model is presented for hadron polarization that is based on
perturbative QCD subprocesses and the recombination of polarized quarks to form
polarized hadrons. The model, originally applied to polarized $\Lambda$'s that
were inclusively produced by proton beams, is extended to include pion beams
and polarized $\Lambda_c$'s. The resulting polarizations are calculated as
functions of $x_F$ and $p_T$ for high energies and are found to be in fair
agreement with recent experiments.
|
[
{
"created": "Fri, 30 Jul 1999 21:23:45 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Goldstein",
"Gary R.",
"",
"Tufts University"
]
] |
A hybrid model is presented for hadron polarization that is based on perturbative QCD subprocesses and the recombination of polarized quarks to form polarized hadrons. The model, originally applied to polarized $\Lambda$'s that were inclusively produced by proton beams, is extended to include pion beams and polarized $\Lambda_c$'s. The resulting polarizations are calculated as functions of $x_F$ and $p_T$ for high energies and are found to be in fair agreement with recent experiments.
|
hep-ph/0104025
|
Robert L. Thews
|
Robert L. Thews and Johann Rafelski
|
J/Psi Production at RHIC in a QGP
|
Presented at Quark Matter 2001, 4 pages, 4 figures, to appear in
Proceedings
|
Nucl.Phys. A698 (2002) 575-578
|
10.1016/S0375-9474(01)01431-2
| null |
hep-ph nucl-th
| null |
In central collisions at RHIC, the initial production of heavy quarks will
for the first time yield multiple pairs of c-cbar in each central event. If a
region of deconfined quarks and gluons is subsequently formed, a new mechanism
for the formation of heavy quarkonium bound states will be activated. This will
result from the mobility of heavy quarks in the deconfined region, such that
bound states can be formed from a quark and an antiquark which were originally
produced in separate incoherent interactions. Our model estimates of this
effect predict a dramatic increase in the number of observed J/Psi at RHIC,
over that predicted from extrapolation of color-screening or gluon dissociation
mechanisms from the lower CERN-SPS energies. The centrality and energy
dependence of this effect should be readily observable by the Star and Phenix
detectors. Thus the J/Psi abundance at RHIC will continue to provide a
signature of QGP formation. However, it is in this environment a more useful
probe, since contrary to prior expectations this large predicted J/Psi
abundance should be relatively easy to measure.
|
[
{
"created": "Mon, 2 Apr 2001 23:19:25 GMT",
"version": "v1"
}
] |
2009-11-07
|
[
[
"Thews",
"Robert L.",
""
],
[
"Rafelski",
"Johann",
""
]
] |
In central collisions at RHIC, the initial production of heavy quarks will for the first time yield multiple pairs of c-cbar in each central event. If a region of deconfined quarks and gluons is subsequently formed, a new mechanism for the formation of heavy quarkonium bound states will be activated. This will result from the mobility of heavy quarks in the deconfined region, such that bound states can be formed from a quark and an antiquark which were originally produced in separate incoherent interactions. Our model estimates of this effect predict a dramatic increase in the number of observed J/Psi at RHIC, over that predicted from extrapolation of color-screening or gluon dissociation mechanisms from the lower CERN-SPS energies. The centrality and energy dependence of this effect should be readily observable by the Star and Phenix detectors. Thus the J/Psi abundance at RHIC will continue to provide a signature of QGP formation. However, it is in this environment a more useful probe, since contrary to prior expectations this large predicted J/Psi abundance should be relatively easy to measure.
|
hep-ph/9702374
|
Stefan Groote
|
Stefan Groote (Universitaet Mainz, Germany)
|
Two-loop Anomalous Dimensions of Heavy Baryon Currents in Heavy Quark
Symmetry
|
9 pages, 2 figures, talk given at the Triangle Graduate School in
Particle Physics, Prague, Czech Republic, September 2--10, 1996
| null | null |
MZ-TH/97-05
|
hep-ph
| null |
This talk presents details of the calculation of two-loop corrections to
heavy baryon currents containing one heavy quark in leading order of the
$1/m_Q$-expansion, i.e. in the limit of Heavy Quark Symmetry (HQS). The
calculations lead to the determination of the anomalous dimension of these
currents. I also discuss problems with different $\gamma_5$-schemes and their
solution by the finite renormalization procedure.
|
[
{
"created": "Thu, 20 Feb 1997 12:53:30 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Groote",
"Stefan",
"",
"Universitaet Mainz, Germany"
]
] |
This talk presents details of the calculation of two-loop corrections to heavy baryon currents containing one heavy quark in leading order of the $1/m_Q$-expansion, i.e. in the limit of Heavy Quark Symmetry (HQS). The calculations lead to the determination of the anomalous dimension of these currents. I also discuss problems with different $\gamma_5$-schemes and their solution by the finite renormalization procedure.
|
hep-ph/9908338
|
L. M. Sehgal
|
L. M. Sehgal
|
CP- and T-Violation in the Decay K_L -> pi+ pi- e+ e- and Related
Processes
|
8 pages including 1 figure, Talk at KAON 99 Conference, Chicago, June
21-26, 1999
| null | null | null |
hep-ph
| null |
I review the theoretical basis of the prediction that the decay K_L -> pi+
pi- e+ e- should show a large CP- and T-violation, a prediction now confirmed
by the KTeV experiment. The genesis of the effect lies in a large violation of
CP- and T-invariance in the decay K_L -> pi+ pi- gamma, which is encrypted in
the polarization state of the photon. The decay K_L -> pi+ pi- e+ e- serves as
an analyser of the photon polarization. The asymmetry in the distribution of
the angle phi between the pi+ pi- and e+ e- planes is a direct measure of the
CP-odd, T-odd component of the photon's Stokes vector. A complete study of the
angular distribution can reveal further CP-violating features, which probe the
non-radiative (charge-radius and short-distance) components of the K_L -> pi+
pi- e+ e- amplitude.
|
[
{
"created": "Thu, 12 Aug 1999 15:33:06 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Sehgal",
"L. M.",
""
]
] |
I review the theoretical basis of the prediction that the decay K_L -> pi+ pi- e+ e- should show a large CP- and T-violation, a prediction now confirmed by the KTeV experiment. The genesis of the effect lies in a large violation of CP- and T-invariance in the decay K_L -> pi+ pi- gamma, which is encrypted in the polarization state of the photon. The decay K_L -> pi+ pi- e+ e- serves as an analyser of the photon polarization. The asymmetry in the distribution of the angle phi between the pi+ pi- and e+ e- planes is a direct measure of the CP-odd, T-odd component of the photon's Stokes vector. A complete study of the angular distribution can reveal further CP-violating features, which probe the non-radiative (charge-radius and short-distance) components of the K_L -> pi+ pi- e+ e- amplitude.
|
1208.5559
|
Louis Lello
|
Louis Lello and Daniel Boyanovsky
|
Searching for sterile neutrinos from $\pi$ and $K$ decays
|
42 pages, 16 figures. To appear in Phys. Rev. D
|
Phys. Rev. D 87, 073017 (2013)
|
10.1103/PhysRevD.87.073017
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The production of heavy sterile neutrinos from $\pi^-,K^-$ decay at rest
yields charged leptons with negative helicity (positive for $\pi^+,K^+$). We
obtain the branching ratio for this process and argue that a Stern-Gerlach
filter leads to spatially separated domains of both helicity components with
abundances determined by the branching ratio. Complemented with a search of
monochromatic peaks, this setup can yield both the mass and mixing angles for
sterile neutrinos with masses in the range $3 MeV \lesssim m_s \lesssim 414
MeV$ in next generation high intensity experiments. We also study oscillations
of light Dirac and Majorana sterile neutrinos with $m_s \simeq eV$ produced in
meson decays including decoherence aspects arising from lifetime effects of the
decaying mesons and the stopping distance of the charged lepton in short
baseline experiments. We obtain the transition probability from production to
detection via charged current interactions including these decoherence effects
for 3+1 and 3+2 scenarios, also studying $|\Delta L|=2$ transitions from
$\bar{\nu} \leftrightarrow \nu$ oscillations for Majorana neutrinos and the
impact of these effects on the determination of CP-violating amplitudes. We
argue that decoherence effects are important in current short baseline
accelerator experiments, leading to an underestimate of masses, mixing and
CP-violating angles. At MiniBooNE/SciBooNE we estimate that these effects lead
to an $\sim 15%$ underestimate for sterile neutrino masses $m_s \gtrsim 3
\,\mathrm{eV}$. We argue that reactor and current short baseline accelerator
experiments are fundamentally different and suggest that in future high
intensity experiments with neutrinos produced from $\pi,K$ decay at rest,
stopping the charged leptons on distances much smaller than the decay length of
the parent meson suppresses considerably these decoherence effects.
|
[
{
"created": "Tue, 28 Aug 2012 04:46:25 GMT",
"version": "v1"
},
{
"created": "Tue, 9 Apr 2013 01:18:38 GMT",
"version": "v2"
}
] |
2013-05-06
|
[
[
"Lello",
"Louis",
""
],
[
"Boyanovsky",
"Daniel",
""
]
] |
The production of heavy sterile neutrinos from $\pi^-,K^-$ decay at rest yields charged leptons with negative helicity (positive for $\pi^+,K^+$). We obtain the branching ratio for this process and argue that a Stern-Gerlach filter leads to spatially separated domains of both helicity components with abundances determined by the branching ratio. Complemented with a search of monochromatic peaks, this setup can yield both the mass and mixing angles for sterile neutrinos with masses in the range $3 MeV \lesssim m_s \lesssim 414 MeV$ in next generation high intensity experiments. We also study oscillations of light Dirac and Majorana sterile neutrinos with $m_s \simeq eV$ produced in meson decays including decoherence aspects arising from lifetime effects of the decaying mesons and the stopping distance of the charged lepton in short baseline experiments. We obtain the transition probability from production to detection via charged current interactions including these decoherence effects for 3+1 and 3+2 scenarios, also studying $|\Delta L|=2$ transitions from $\bar{\nu} \leftrightarrow \nu$ oscillations for Majorana neutrinos and the impact of these effects on the determination of CP-violating amplitudes. We argue that decoherence effects are important in current short baseline accelerator experiments, leading to an underestimate of masses, mixing and CP-violating angles. At MiniBooNE/SciBooNE we estimate that these effects lead to an $\sim 15%$ underestimate for sterile neutrino masses $m_s \gtrsim 3 \,\mathrm{eV}$. We argue that reactor and current short baseline accelerator experiments are fundamentally different and suggest that in future high intensity experiments with neutrinos produced from $\pi,K$ decay at rest, stopping the charged leptons on distances much smaller than the decay length of the parent meson suppresses considerably these decoherence effects.
|
hep-ph/0003091
|
John F. Gunion
|
B. Grzadkowski, J.F. Gunion, J. Pliszka
|
How Valuable is Polarization at a Muon Collider? A Test Case:
Determining the CP Nature of a Higgs Boson
|
33 pages, 10 figures, equations.sty
|
Nucl.Phys.B583:49-75,2000
|
10.1016/S0550-3213(00)00229-7
|
UCD-99-23
|
hep-ph
| null |
We study the use of polarization asymmetries at a muon collider to determine
the CP-even and CP-odd couplings of a Higgs boson to $\mu^+mu^-$. We determine
achievable accuracy as a function of beam polarization and luminosity. The
appropriate techniques for dealing with the polarization precession are
outlined. Strategies especially appropriate for a two-Higgs-doublet model
(including the MSSM) are given. Our general conclusion is that polarization
will be very useful, especially if the proton source is such that full
luminosity in the storage ring can be retained even after imposing cuts on the
originally accepted muons necessary for $P\gsim 0.4$ for each beam.
|
[
{
"created": "Fri, 10 Mar 2000 00:03:34 GMT",
"version": "v1"
}
] |
2009-09-15
|
[
[
"Grzadkowski",
"B.",
""
],
[
"Gunion",
"J. F.",
""
],
[
"Pliszka",
"J.",
""
]
] |
We study the use of polarization asymmetries at a muon collider to determine the CP-even and CP-odd couplings of a Higgs boson to $\mu^+mu^-$. We determine achievable accuracy as a function of beam polarization and luminosity. The appropriate techniques for dealing with the polarization precession are outlined. Strategies especially appropriate for a two-Higgs-doublet model (including the MSSM) are given. Our general conclusion is that polarization will be very useful, especially if the proton source is such that full luminosity in the storage ring can be retained even after imposing cuts on the originally accepted muons necessary for $P\gsim 0.4$ for each beam.
|
hep-ph/9706288
| null |
F. Caravaglios
|
A Scenario for Contact Interactions at HERA
|
8 pages, LaTeX, no figure
|
Phys.Lett. B423 (1998) 395-400
|
10.1016/S0370-2693(98)00149-X
|
CERN-TH/97-104
|
hep-ph
| null |
The four fermion contact interactions, required to explain the anomalous HERA
result, could come from the exchange of new heavy (probably composite)
resonances. Depending on their charges and quantum numbers, one gets different
scenarios and finds that many of these configurations are unsuitable. For
example, new neutral resonances seems to be disfavored by the data coming from
the TEVATRON, LEP 2 and atomic parity violation. These experiments allow only
few helicity combinations that cannot arise from neutral currents in a natural
way. On the contrary, a global large symmetry SU(8) * SU(8) (which is contained
in SU(16)) embeds some lepto-quarks of spin 1 that could give suitable four
fermion interactions (compatible with all other experiments) if these
resonances are the lightest new (probably composite) states with a mass
comparable to the scale of the contact interactions.
|
[
{
"created": "Mon, 9 Jun 1997 16:10:38 GMT",
"version": "v1"
}
] |
2009-10-30
|
[
[
"Caravaglios",
"F.",
""
]
] |
The four fermion contact interactions, required to explain the anomalous HERA result, could come from the exchange of new heavy (probably composite) resonances. Depending on their charges and quantum numbers, one gets different scenarios and finds that many of these configurations are unsuitable. For example, new neutral resonances seems to be disfavored by the data coming from the TEVATRON, LEP 2 and atomic parity violation. These experiments allow only few helicity combinations that cannot arise from neutral currents in a natural way. On the contrary, a global large symmetry SU(8) * SU(8) (which is contained in SU(16)) embeds some lepto-quarks of spin 1 that could give suitable four fermion interactions (compatible with all other experiments) if these resonances are the lightest new (probably composite) states with a mass comparable to the scale of the contact interactions.
|
hep-ph/9611294
|
Andrej Arbuzov
|
E.A. Kuraev (Dubna, JINR)
|
Radiative Tail in $\pi_{e2}$ Decay and Some Comments on $\mu-e$
Universality
|
5 pages, LaTeX, some misprints are corrected, submitted to Pisma Zh.
Eksp. Teor. Fiz
|
JETP Lett. 65 (1997) 127-130
|
10.1134/1.567302
|
E2-96-93
|
hep-ph
| null |
The result of lowest-order perturbation theory calculations of the photon and
positron spectra in radiative pion(e2) decay are generalized to all orders of
perturbation theory using the structure-function method. An additional source
of radiative corrections to the ratio of the positron and muon channels of pion
decay, due to emission of virtual and real photons and pairs, is considered. It
depends on details of the detection of the final particles and is large enough
to be taken into account in theoretical estimates with a level of accuracy of
0.1%.
|
[
{
"created": "Mon, 11 Nov 1996 09:01:27 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jan 1997 08:42:34 GMT",
"version": "v2"
}
] |
2009-10-30
|
[
[
"Kuraev",
"E. A.",
"",
"Dubna, JINR"
]
] |
The result of lowest-order perturbation theory calculations of the photon and positron spectra in radiative pion(e2) decay are generalized to all orders of perturbation theory using the structure-function method. An additional source of radiative corrections to the ratio of the positron and muon channels of pion decay, due to emission of virtual and real photons and pairs, is considered. It depends on details of the detection of the final particles and is large enough to be taken into account in theoretical estimates with a level of accuracy of 0.1%.
|
hep-ph/9706513
|
Konstantinos Dimopoulos
|
Konstantinos Dimopoulos
|
Primordial Magnetic Fields from Superconducting Cosmic Strings
|
26 pages, LaTeX. (2 figures)
|
Phys.Rev.D57:4629-4641,1998
|
10.1103/PhysRevD.57.4629
|
DAMTP-97-30
|
hep-ph
| null |
Cosmic strings are stable topological defects that may have been created at a
phase transition in the early universe. It is a growing belief that, for a wide
range of theoretical models, such strings may be superconducting and carry
substantial currents which have important astrophysical and cosmological
effects. This paper explores the possibility of generation of a primordial
magnetic field by a network of charged-current carrying cosmic strings. The
field is created by vorticity, generated in the primordial plasma due to the
strings' motion and gravitational pull. In the case of superconducting strings
formed at the breaking of grand unification, it is found that strong magnetic
fields of high coherence can be generated in that way. Such fields could
account for the observed galactic and intergalactic magnetic fields since they
suffice to seed magnetic dynamos on galactic scales.
|
[
{
"created": "Thu, 26 Jun 1997 10:11:15 GMT",
"version": "v1"
}
] |
2010-11-19
|
[
[
"Dimopoulos",
"Konstantinos",
""
]
] |
Cosmic strings are stable topological defects that may have been created at a phase transition in the early universe. It is a growing belief that, for a wide range of theoretical models, such strings may be superconducting and carry substantial currents which have important astrophysical and cosmological effects. This paper explores the possibility of generation of a primordial magnetic field by a network of charged-current carrying cosmic strings. The field is created by vorticity, generated in the primordial plasma due to the strings' motion and gravitational pull. In the case of superconducting strings formed at the breaking of grand unification, it is found that strong magnetic fields of high coherence can be generated in that way. Such fields could account for the observed galactic and intergalactic magnetic fields since they suffice to seed magnetic dynamos on galactic scales.
|
hep-ph/9910279
|
Piotr Duka
|
P. Duka, J. Gluza and M. Zralek
|
Quantization and renormalization of the manifest left-right symmetric
model of electroweak interactions
|
74 pages, 65 Postscript figures, submitted to Annals of Physics
|
Annals Phys.280:336-408,2000
|
10.1006/aphy.1999.5988
| null |
hep-ph
| null |
Quantization and renormalization of the left-right symmetric model is the
main purpose of the paper. First the model at tree level with a Higgs sector
containing one bidoublet and two triplets is precisely discussed. Then the
canonical quantization and Faddeev-Popov Lagrangian are carried out ('t Hooft
gauge). The BRST symmetry is discussed. Subsequently the on mass shell
renormalization is performed and, as a test of consistency, the renormalization
of the ZNiNj vertex is analyzed.
|
[
{
"created": "Fri, 8 Oct 1999 12:52:57 GMT",
"version": "v1"
}
] |
2014-11-17
|
[
[
"Duka",
"P.",
""
],
[
"Gluza",
"J.",
""
],
[
"Zralek",
"M.",
""
]
] |
Quantization and renormalization of the left-right symmetric model is the main purpose of the paper. First the model at tree level with a Higgs sector containing one bidoublet and two triplets is precisely discussed. Then the canonical quantization and Faddeev-Popov Lagrangian are carried out ('t Hooft gauge). The BRST symmetry is discussed. Subsequently the on mass shell renormalization is performed and, as a test of consistency, the renormalization of the ZNiNj vertex is analyzed.
|
2203.01510
|
Bin Yan
|
Bin Yan
|
Probing the dark photon via polarized DIS scattering at the HERA and EIC
|
5 pages, 2 figures, the published version
| null |
10.1016/j.physletb.2022.137384
|
LA-UR-22-21939
|
hep-ph hep-ex nucl-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The dark photon is widely predicted in many new physics beyond the Standard
Model. In this work, we propose to utilize the polarized lepton cross section
in neutral current DIS process at the HERA and upcoming Electron-Ion Collider
(EIC) to probe the properties of the dark photon. It shows that we can
constrain the mixing parameter $\epsilon<0.02$ when the dark photon mass
$m_{A_D}<10 ~{\rm GeV}$ at the HERA with polarized lepton beam and this bound
is comparable to the limit from the unpolarized HERA data. With the help of
high integrated luminosity and high electron beam polarization of the EIC, the
upper limit of the $\epsilon$ could be further improved. Depending on the
assumption of the systematic error of the cross section measurements, we obtain
$\epsilon<0.01\sim 0.02$ for the mass region $m_{A_D}<10~{\rm GeV}$ under the
integrated luminosity of $300~{\rm fb}^{-1}$. We also discuss the complementary
roles between the cross section and the single-spin asymmetry measurements in
probing the dark photon.
|
[
{
"created": "Thu, 3 Mar 2022 04:39:01 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Aug 2022 11:15:55 GMT",
"version": "v2"
}
] |
2022-08-24
|
[
[
"Yan",
"Bin",
""
]
] |
The dark photon is widely predicted in many new physics beyond the Standard Model. In this work, we propose to utilize the polarized lepton cross section in neutral current DIS process at the HERA and upcoming Electron-Ion Collider (EIC) to probe the properties of the dark photon. It shows that we can constrain the mixing parameter $\epsilon<0.02$ when the dark photon mass $m_{A_D}<10 ~{\rm GeV}$ at the HERA with polarized lepton beam and this bound is comparable to the limit from the unpolarized HERA data. With the help of high integrated luminosity and high electron beam polarization of the EIC, the upper limit of the $\epsilon$ could be further improved. Depending on the assumption of the systematic error of the cross section measurements, we obtain $\epsilon<0.01\sim 0.02$ for the mass region $m_{A_D}<10~{\rm GeV}$ under the integrated luminosity of $300~{\rm fb}^{-1}$. We also discuss the complementary roles between the cross section and the single-spin asymmetry measurements in probing the dark photon.
|
hep-ph/0112329
|
Toshihiko Ota
|
Toshihiko Ota, Joe Sato, Nao-aki Yamashita
|
Oscillation enhanced search for new interaction with neutrinos
|
25 pages, 20 figures
|
Phys.Rev.D65:093015,2002
|
10.1103/PhysRevD.65.093015
|
KYUSHU-HET58
|
hep-ph
| null |
We discuss the measurement of new physics in long baseline neutrino
oscillation experiments. Through the neutrino oscillation, the probability to
detect the new physics effects such as flavor violation is enhanced by the
interference with the weak interaction. We carefully explain the situations
that the interference can take place. Assuming a neutrino factory and an
upgraded conventional beam, we estimate the feasibility to observe new physics
numerically and point out that we can search new interactions using some
channels, for example $\nu_{\mu} \to \nu_{\mu}$, in these experiments. We also
discuss several models which induce the effective interactions interfering with
the weak interaction, and show that some new physics effects are large enough
to be observed in the oscillation enhanced way.
|
[
{
"created": "Wed, 26 Dec 2001 10:04:10 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Dec 2001 07:05:17 GMT",
"version": "v2"
}
] |
2011-02-21
|
[
[
"Ota",
"Toshihiko",
""
],
[
"Sato",
"Joe",
""
],
[
"Yamashita",
"Nao-aki",
""
]
] |
We discuss the measurement of new physics in long baseline neutrino oscillation experiments. Through the neutrino oscillation, the probability to detect the new physics effects such as flavor violation is enhanced by the interference with the weak interaction. We carefully explain the situations that the interference can take place. Assuming a neutrino factory and an upgraded conventional beam, we estimate the feasibility to observe new physics numerically and point out that we can search new interactions using some channels, for example $\nu_{\mu} \to \nu_{\mu}$, in these experiments. We also discuss several models which induce the effective interactions interfering with the weak interaction, and show that some new physics effects are large enough to be observed in the oscillation enhanced way.
|
hep-ph/9807513
|
Mark Wusthoff
|
K. Golec-Biernat, M. Wusthoff
|
Saturation Effects in Deep Inelastic Scattering at low $Q^2$ and its
Implications on Diffraction
|
24 pages, 12 figures, Latex-file
|
Phys.Rev.D59:014017,1998
|
10.1103/PhysRevD.59.014017
|
DTP/98/50
|
hep-ph
| null |
We present a model based on the concept of saturation for small $Q^2$ and
small $x$. With only three parameters we achieve a good description of all Deep
Inelastic Scattering data below $x=0.01$. This includes a consistent treatment
of charm and a successful extrapolation into the photoproduction regime. The
same model leads to a roughly constant ratio of diffractive and inclusive cross
section.
|
[
{
"created": "Mon, 27 Jul 1998 17:07:01 GMT",
"version": "v1"
}
] |
2010-05-12
|
[
[
"Golec-Biernat",
"K.",
""
],
[
"Wusthoff",
"M.",
""
]
] |
We present a model based on the concept of saturation for small $Q^2$ and small $x$. With only three parameters we achieve a good description of all Deep Inelastic Scattering data below $x=0.01$. This includes a consistent treatment of charm and a successful extrapolation into the photoproduction regime. The same model leads to a roughly constant ratio of diffractive and inclusive cross section.
|
hep-ph/0309323
|
Hiroaki Sugiyama
|
Hisakazu Minakata, Hiroaki Sugiyama
|
Exploring Leptonic CP Violation by Reactor and Neutrino Superbeam
Experiments
|
18 pages, 5 figures, uses revtex4 and graphicx, revised treatment of
parameter degeneracy due to unknown sign of Dm^2 and tightened CP sensitivity
by using projected chi^2
|
Phys.Lett. B580 (2004) 216-228
|
10.1016/j.physletb.2003.11.048
| null |
hep-ph hep-ex
| null |
We point out the possibility that reactor measurement of theta_{13}, when
combined with high-statistics nu_e appearance accelerator experiments, can
detect leptonic CP violation. Our proposal is based on a careful statistical
analysis under reasonable assumptions on systematic errors, assuming 2 years
running of the neutrino mode J-PARC -> Hyper-Kamiokande experiment and a few
years running of a reactor experiment with 100 ton detectors at the
Kashiwazaki-Kariwa nuclear power plant. We show that the method can be arranged
to be insensitive to the intrinsic parameter degeneracy but is affected by the
one due to unknown sign of Delta m^2_{31}.
|
[
{
"created": "Mon, 29 Sep 2003 13:32:07 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Nov 2003 11:59:59 GMT",
"version": "v2"
}
] |
2010-04-05
|
[
[
"Minakata",
"Hisakazu",
""
],
[
"Sugiyama",
"Hiroaki",
""
]
] |
We point out the possibility that reactor measurement of theta_{13}, when combined with high-statistics nu_e appearance accelerator experiments, can detect leptonic CP violation. Our proposal is based on a careful statistical analysis under reasonable assumptions on systematic errors, assuming 2 years running of the neutrino mode J-PARC -> Hyper-Kamiokande experiment and a few years running of a reactor experiment with 100 ton detectors at the Kashiwazaki-Kariwa nuclear power plant. We show that the method can be arranged to be insensitive to the intrinsic parameter degeneracy but is affected by the one due to unknown sign of Delta m^2_{31}.
|
1409.8631
|
Rhorry Gauld
|
Rhorry Gauld
|
Leptonic top-quark asymmetry predictions at LHCb
|
7 pages, 4 figures, 6 tables. Directors cut: matches PRD version with
updated references and comments
| null |
10.1103/PhysRevD.91.054029
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The forward LHCb acceptance offers the possibility of measuring the top-quark
pair asymmetry in a kinematic region that does not receive overwhelming
dilution from the symmetric gluon-fusion channel. To investigate this
possibility, two leptonic final states are identified, and analysis strategies
are proposed for each channel with 14~TeV data. Leading fixed-order predictions
are then provided for the relevant leptonic asymmetry variables in each
channel. If backgrounds can be experimentally constrained, statistically, a
non-zero asymmetry is estimated to be observable beyond 5$\sigma$ confidence
level with the full LHCb 14~TeV data.
|
[
{
"created": "Tue, 30 Sep 2014 17:07:08 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Dec 2015 15:22:30 GMT",
"version": "v2"
}
] |
2015-12-29
|
[
[
"Gauld",
"Rhorry",
""
]
] |
The forward LHCb acceptance offers the possibility of measuring the top-quark pair asymmetry in a kinematic region that does not receive overwhelming dilution from the symmetric gluon-fusion channel. To investigate this possibility, two leptonic final states are identified, and analysis strategies are proposed for each channel with 14~TeV data. Leading fixed-order predictions are then provided for the relevant leptonic asymmetry variables in each channel. If backgrounds can be experimentally constrained, statistically, a non-zero asymmetry is estimated to be observable beyond 5$\sigma$ confidence level with the full LHCb 14~TeV data.
|
2402.16737
|
Ipsita Ray
|
Rusa Mandal, Praveen S Patil, Ipsita Ray
|
Probing the inverse moment of $B_s$-meson distribution amplitude via
$B_s \to \eta_s$ form factors
|
Version accepted for publication in JHEP
| null |
10.1007/JHEP06(2024)212 10.1007/JHEP06(2024)212 10.1007/JHEP06(2024)212
10.1007/JHEP06(2024)212
| null |
hep-ph hep-ex hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate the inverse moment of the $B_s$-meson light-cone distribution
amplitude (LCDA), denoted as $\lambda_{B_s}$ and defined within the heavy quark
effective theory, through the calculation of $B_s \to \eta_s$ form factors. The
presence of the $s$-quark inside the $B_s$-meson dictates a notable departure
of approximately $20\%$ in the $\lambda_{B_s}$ value compared to the
non-strange case $\lambda_{B_q}$, as computed within the QCD sum rule approach,
albeit with significant uncertainty. First, we compute the decay constant of
the $\eta_s$-meson utilizing two-point sum rules while retaining finite
$s$-quark mass contributions. Next, we constrain the parameter $\lambda_{B_s}$
by calculating $B_s \to \eta_s$ form factors within the light-cone sum rule
approach, using $B_s$-meson LCDAs, and leveraging Lattice QCD estimates at zero
momentum transfer from the HPQCD collaboration. Our findings yield
$\lambda_{B_s}$ = 480 $\pm$ 92 MeV when expressing the $B_s$-meson LCDAs in the
Exponential model, consistent with previous QCD sum rule estimate yet
exhibiting a 1.5-fold improvement in uncertainty. Furthermore, we compare the
form factor predictions, based on the extracted $\lambda_{B_s}$ value, with
earlier analyses for other channels such as $B_s \to D_s$ and $B_s \to K$.
|
[
{
"created": "Mon, 26 Feb 2024 17:00:49 GMT",
"version": "v1"
},
{
"created": "Mon, 4 Mar 2024 17:28:34 GMT",
"version": "v2"
},
{
"created": "Tue, 11 Jun 2024 17:15:35 GMT",
"version": "v3"
},
{
"created": "Wed, 3 Jul 2024 08:59:13 GMT",
"version": "v4"
}
] |
2024-07-04
|
[
[
"Mandal",
"Rusa",
""
],
[
"Patil",
"Praveen S",
""
],
[
"Ray",
"Ipsita",
""
]
] |
We investigate the inverse moment of the $B_s$-meson light-cone distribution amplitude (LCDA), denoted as $\lambda_{B_s}$ and defined within the heavy quark effective theory, through the calculation of $B_s \to \eta_s$ form factors. The presence of the $s$-quark inside the $B_s$-meson dictates a notable departure of approximately $20\%$ in the $\lambda_{B_s}$ value compared to the non-strange case $\lambda_{B_q}$, as computed within the QCD sum rule approach, albeit with significant uncertainty. First, we compute the decay constant of the $\eta_s$-meson utilizing two-point sum rules while retaining finite $s$-quark mass contributions. Next, we constrain the parameter $\lambda_{B_s}$ by calculating $B_s \to \eta_s$ form factors within the light-cone sum rule approach, using $B_s$-meson LCDAs, and leveraging Lattice QCD estimates at zero momentum transfer from the HPQCD collaboration. Our findings yield $\lambda_{B_s}$ = 480 $\pm$ 92 MeV when expressing the $B_s$-meson LCDAs in the Exponential model, consistent with previous QCD sum rule estimate yet exhibiting a 1.5-fold improvement in uncertainty. Furthermore, we compare the form factor predictions, based on the extracted $\lambda_{B_s}$ value, with earlier analyses for other channels such as $B_s \to D_s$ and $B_s \to K$.
|
1005.2490
|
George Rupp
|
George Rupp, Susana Coito, and Eef van Beveren
|
Complex masses in the S-matrix
|
6 pages, 2 figures, Acta Physica Polonica B style; plenary talk given
by George Rupp at the workshop Excited QCD 2010, 31 Jan. - 6 Feb. 2010 in
Stara Lesna, Slovakia
|
Acta Phys.Polon.Supp.3:931-936,2010
| null | null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Most excited hadrons have multiparticle strong decay modes, which can often
be described as resulting from intermediate states containing one or two
resonances. In a theoretical approach, such a description in terms of
quasi-two-particle initial and final states leads to unitarity violations,
because of the complex masses of the involved resonances. In the present paper,
an empirical algebraic procedure is presented to restore unitarity of the
S-matrix while preserving its symmetry. Preliminary results are presented in a
first application to S-wave pion-pion scattering, in the framework of the
Resonance-Spectrum Expansion.
|
[
{
"created": "Fri, 14 May 2010 09:57:58 GMT",
"version": "v1"
}
] |
2015-03-17
|
[
[
"Rupp",
"George",
""
],
[
"Coito",
"Susana",
""
],
[
"van Beveren",
"Eef",
""
]
] |
Most excited hadrons have multiparticle strong decay modes, which can often be described as resulting from intermediate states containing one or two resonances. In a theoretical approach, such a description in terms of quasi-two-particle initial and final states leads to unitarity violations, because of the complex masses of the involved resonances. In the present paper, an empirical algebraic procedure is presented to restore unitarity of the S-matrix while preserving its symmetry. Preliminary results are presented in a first application to S-wave pion-pion scattering, in the framework of the Resonance-Spectrum Expansion.
|
hep-ph/0507236
|
Kathryn Zurek
|
David B. Kaplan and Kathryn M. Zurek
|
Exotic Axions
|
5 pages, 1 figure, References added
|
Phys.Rev.Lett. 96 (2006) 041301
|
10.1103/PhysRevLett.96.041301
| null |
hep-ph astro-ph hep-ex
| null |
We show that axion phenomenology may be significantly different than
conventionally assumed in theories which exhibit late phase transitions (below
the QCD scale). In such theories one can find multiple pseudoscalars with
axion-like couplings to matter, including a string scale axion, whose decay
constant far exceeds the conventional cosmological bound. Such theories have
several dark matter candidates.
|
[
{
"created": "Wed, 20 Jul 2005 01:50:37 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jul 2005 00:01:50 GMT",
"version": "v2"
}
] |
2009-11-11
|
[
[
"Kaplan",
"David B.",
""
],
[
"Zurek",
"Kathryn M.",
""
]
] |
We show that axion phenomenology may be significantly different than conventionally assumed in theories which exhibit late phase transitions (below the QCD scale). In such theories one can find multiple pseudoscalars with axion-like couplings to matter, including a string scale axion, whose decay constant far exceeds the conventional cosmological bound. Such theories have several dark matter candidates.
|
1301.5845
|
David d'Enterria
|
David d'Enterria and Alexander M. Snigirev
|
Enhanced J/Psi-pair production from double parton scatterings in
nucleus-nucleus collisions at the Large Hadron Collider
|
7 pages, 3 figures, 1 table
| null |
10.1016/j.physletb.2013.10.004
| null |
hep-ph nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A generic expression of double-parton scattering cross sections in
high-energy nucleus-nucleus (A-A) collisions is derived as a function of the
corresponding single-parton hard cross sections and of the A-A event
centrality. We consider the case of prompt-J/psi production in lead-lead
(Pb-Pb) at the CERN Large Hadron Collider and find that about 20% (35%) of the
J/psi events in minimum-bias (most central) collisions contain a second J/psi
from double parton interactions. In Pb-Pb at 5.5 TeV, in the absence of
final-state effects, about 240 double-J/psi events are expected per unit
midrapidity and per inverse-nanobarn in the dilepton decay modes. The
implications of double-J/psi production on the interpretation of the observed
J/psi suppression in A-A collisions are discussed.
|
[
{
"created": "Thu, 24 Jan 2013 17:10:18 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Jun 2013 17:36:43 GMT",
"version": "v2"
}
] |
2013-11-08
|
[
[
"d'Enterria",
"David",
""
],
[
"Snigirev",
"Alexander M.",
""
]
] |
A generic expression of double-parton scattering cross sections in high-energy nucleus-nucleus (A-A) collisions is derived as a function of the corresponding single-parton hard cross sections and of the A-A event centrality. We consider the case of prompt-J/psi production in lead-lead (Pb-Pb) at the CERN Large Hadron Collider and find that about 20% (35%) of the J/psi events in minimum-bias (most central) collisions contain a second J/psi from double parton interactions. In Pb-Pb at 5.5 TeV, in the absence of final-state effects, about 240 double-J/psi events are expected per unit midrapidity and per inverse-nanobarn in the dilepton decay modes. The implications of double-J/psi production on the interpretation of the observed J/psi suppression in A-A collisions are discussed.
|
1109.5219
|
Zhi-Gang Wang
|
Zhi-Gang Wang
|
Analysis of mass modifications of the vector and axial-vector heavy
mesons in the nuclear matter with the QCD sum rules
|
15 pages, 12 figures
|
Int.J.Mod.Phys.A28(2013)1350049
|
10.1142/S0217751X13500498
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this article, we calculate the mass modifications of the vector and
axial-vector mesons $D^*$, $B^*$, $D_1$ and $B_1$ in the nuclear matter with
the QCD sum rules, and obtain the mass-shifts $\delta M_{D^*}=-71 \rm{MeV}$,
$\delta M_{B^*}=-380 \rm{MeV}$, $\delta M_{D_1}=72 \rm{MeV}$, $\delta
M_{B_1}=264 \rm{MeV}$, and the scattering lengths $a_{D^*}=-1.07 \rm{fm}$,
$a_{B^*}=-7.17 \rm{fm}$, $a_{D_1}=1.15 \rm{fm}$ and $a_{B_1}=5.03 \rm{fm}$ for
the $D^*N$, $B^*N$, $D_1N$ and $B_1N$ interactions, respectively.
|
[
{
"created": "Sat, 24 Sep 2011 00:50:00 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Jan 2012 09:24:16 GMT",
"version": "v2"
},
{
"created": "Sat, 25 Feb 2012 09:43:19 GMT",
"version": "v3"
},
{
"created": "Fri, 3 Aug 2012 04:22:26 GMT",
"version": "v4"
},
{
"created": "Wed, 26 Sep 2012 08:50:41 GMT",
"version": "v5"
}
] |
2014-02-14
|
[
[
"Wang",
"Zhi-Gang",
""
]
] |
In this article, we calculate the mass modifications of the vector and axial-vector mesons $D^*$, $B^*$, $D_1$ and $B_1$ in the nuclear matter with the QCD sum rules, and obtain the mass-shifts $\delta M_{D^*}=-71 \rm{MeV}$, $\delta M_{B^*}=-380 \rm{MeV}$, $\delta M_{D_1}=72 \rm{MeV}$, $\delta M_{B_1}=264 \rm{MeV}$, and the scattering lengths $a_{D^*}=-1.07 \rm{fm}$, $a_{B^*}=-7.17 \rm{fm}$, $a_{D_1}=1.15 \rm{fm}$ and $a_{B_1}=5.03 \rm{fm}$ for the $D^*N$, $B^*N$, $D_1N$ and $B_1N$ interactions, respectively.
|
hep-ph/0508233
|
Zurab Berezhiani
|
Zurab Berezhiani
|
Through the Looking-Glass: Alice's Adventures in Mirror World
|
Published in Ian Kogan Memorial Collection "From Fields to Strings:
Circumnavigating Theoretical Physics", Eds. M. Shifman et al., World
Scientific, Singapore, vol. 3, pp. 2147-2195. 49pp., 8 Figures
| null |
10.1142/9789812775344_0055
| null |
hep-ph
| null |
We briefly review the concept of a parallel `mirror' world which has the same
particle physics as the observable world and couples to the latter by gravity
and perhaps other very weak forces. The nucleosynthesis bounds demand that the
mirror world should have a smaller temperature than the ordinary one. By this
reason its evolution should substantially deviate from the standard cosmology
as far as the crucial epochs like baryogenesis, nucleosynthesis etc. are
concerned. In particular, we show that in the context of certain baryogenesis
scenarios, the baryon asymmetry in the mirror world should be larger than in
the observable one. Moreover, we show that mirror baryons could naturally
constitute the dominant dark matter component of the Universe, and discuss its
cosmological implications.
|
[
{
"created": "Mon, 22 Aug 2005 18:18:59 GMT",
"version": "v1"
}
] |
2016-11-23
|
[
[
"Berezhiani",
"Zurab",
""
]
] |
We briefly review the concept of a parallel `mirror' world which has the same particle physics as the observable world and couples to the latter by gravity and perhaps other very weak forces. The nucleosynthesis bounds demand that the mirror world should have a smaller temperature than the ordinary one. By this reason its evolution should substantially deviate from the standard cosmology as far as the crucial epochs like baryogenesis, nucleosynthesis etc. are concerned. In particular, we show that in the context of certain baryogenesis scenarios, the baryon asymmetry in the mirror world should be larger than in the observable one. Moreover, we show that mirror baryons could naturally constitute the dominant dark matter component of the Universe, and discuss its cosmological implications.
|
hep-ph/9411269
| null |
A. Bramon, A. Grau, G. Pancheri
|
Effective Chiral Lagrangians with an SU(3)-Broken Vector-Meson Sector
|
10 pages, LaTeX file, A postscript version can be obtained from
anonymous ftp at ftp://ftp.ifae.es/preprint.ft/ )
|
Phys.Lett. B345 (1995) 263-268
|
10.1016/0370-2693(94)01625-M
|
UAB-FT-335/94
|
hep-ph
| null |
The accuracy of effective chiral lagrangians including vector-mesons as
(hidden symmetry) gauge fields is shown to be improved by taking into account
SU(3)-breaking in the vector-meson sector. The masses, $M_V$, and couplings to
the photon field and pseudoscalar pairs, $f_{V\gamma}$ and $g_{VPP}$, are all
consistently described in terms of two parameters, which also fit the values
for the pseudoscalar decay-constants, $f_P$, and charge radii, $<r^2_P>$. The
description of the latter is further improved when working in the context of
chiral perturbation theory.
|
[
{
"created": "Fri, 11 Nov 1994 16:51:15 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Bramon",
"A.",
""
],
[
"Grau",
"A.",
""
],
[
"Pancheri",
"G.",
""
]
] |
The accuracy of effective chiral lagrangians including vector-mesons as (hidden symmetry) gauge fields is shown to be improved by taking into account SU(3)-breaking in the vector-meson sector. The masses, $M_V$, and couplings to the photon field and pseudoscalar pairs, $f_{V\gamma}$ and $g_{VPP}$, are all consistently described in terms of two parameters, which also fit the values for the pseudoscalar decay-constants, $f_P$, and charge radii, $<r^2_P>$. The description of the latter is further improved when working in the context of chiral perturbation theory.
|
hep-ph/0201284
|
Werner Porod
|
W. Porod and W. Majerotto
|
Large lepton flavor violating signals in supersymmetric particle decays
at future e+ e- colliders
|
LaTex, 10 pages, 3 figures, uses revtex4
|
Phys.Rev. D66 (2002) 015003
|
10.1103/PhysRevD.66.015003
|
HEPHY-PUB 752, ZU-TH 4/02
|
hep-ph
| null |
We study lepton flavor violating signals at a future e+ e- linear collider
within the general MSSM, allowing for the most general flavor structure. We
demonstrate that there is a large region in parameter space with large signals,
while being consistent with present experimental bounds on rare lepton decays
such as mu -> e gamma. In our analysis, we include all possible signals from
charged slepton and sneutrino production and their decays as well as from the
decays of neutralinos and charginos. We also consider the background from the
Standard Model and the MSSM. We find that in general the signature e tau
missing energy is the most pronounced one. We demonstrate that even for an
integrated luminosity of 100 inverse fb the signal can be large. At a high
luminosity linear collider, precision experiments will allow one to determine
the lepton flavor structure of the MSSM.
|
[
{
"created": "Wed, 30 Jan 2002 13:58:13 GMT",
"version": "v1"
}
] |
2009-11-07
|
[
[
"Porod",
"W.",
""
],
[
"Majerotto",
"W.",
""
]
] |
We study lepton flavor violating signals at a future e+ e- linear collider within the general MSSM, allowing for the most general flavor structure. We demonstrate that there is a large region in parameter space with large signals, while being consistent with present experimental bounds on rare lepton decays such as mu -> e gamma. In our analysis, we include all possible signals from charged slepton and sneutrino production and their decays as well as from the decays of neutralinos and charginos. We also consider the background from the Standard Model and the MSSM. We find that in general the signature e tau missing energy is the most pronounced one. We demonstrate that even for an integrated luminosity of 100 inverse fb the signal can be large. At a high luminosity linear collider, precision experiments will allow one to determine the lepton flavor structure of the MSSM.
|
2008.10791
|
Bo Feng
|
Bo Feng, De-fu Hou, Hai-cang Ren, and Shuai Yuan
|
The noncommutativity of the static and homogeneous limit of the axial
chemical potential in chiral magnetic effect
|
16 pages, 4 figures
|
Phys. Rev. D 103, 056004 (2021)
|
10.1103/PhysRevD.103.056004
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the noncommutativity of different orders of zero energy-momentum
limit pertaining to the axial chemical potential in the chiral magnetic effect.
While this noncommutativity issue originates from the pinching singularity at
one-loop order, it cannot be removed by introducing a damping term to the
fermion propagators. The physical reason is that modifying the propagator alone
would violate the axial-vector Ward identity and as a result a modification of
the longitudinal component of the axial-vector vertex is required, which
contributes to CME. The pinching singularity with free fermion propagators was
then taken over by the singularity stemming from the dressed axial-vector
vertex. We show this mechanism by a concrete example. Moreover, we proved in
general the vanishing CME in the limit order that the static limit was taken
prior to the homogeneous limit in the light of Coleman-Hill theorem for a
static external magnetic field. For the opposite limit that the homogeneous
limit is taken first, we show that the nonvanishing CME was a consequence of
the nonrenormalizability of chiral anomaly for an arbitrary external magnetic
field.
|
[
{
"created": "Tue, 25 Aug 2020 02:51:52 GMT",
"version": "v1"
}
] |
2021-03-10
|
[
[
"Feng",
"Bo",
""
],
[
"Hou",
"De-fu",
""
],
[
"Ren",
"Hai-cang",
""
],
[
"Yuan",
"Shuai",
""
]
] |
We study the noncommutativity of different orders of zero energy-momentum limit pertaining to the axial chemical potential in the chiral magnetic effect. While this noncommutativity issue originates from the pinching singularity at one-loop order, it cannot be removed by introducing a damping term to the fermion propagators. The physical reason is that modifying the propagator alone would violate the axial-vector Ward identity and as a result a modification of the longitudinal component of the axial-vector vertex is required, which contributes to CME. The pinching singularity with free fermion propagators was then taken over by the singularity stemming from the dressed axial-vector vertex. We show this mechanism by a concrete example. Moreover, we proved in general the vanishing CME in the limit order that the static limit was taken prior to the homogeneous limit in the light of Coleman-Hill theorem for a static external magnetic field. For the opposite limit that the homogeneous limit is taken first, we show that the nonvanishing CME was a consequence of the nonrenormalizability of chiral anomaly for an arbitrary external magnetic field.
|
1205.0611
|
J. P. Ma
|
J. P. Ma and Q. Wang
|
Scale Dependence of Twist-3 Quark-Gluon Operators for Single Spin
Asymmetries
|
typo in Eq.(10) corrected, references added
| null |
10.1016/j.physletb.2012.07.036
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We derive the scale dependence of twist-3 quark-gluon operators, or ETQS
matrix elements, at one-loop. These operators are used to factorize transverse
single spin asymmetries, which are studied intensively both in experiment and
theory. The scale dependence of two special cases are particularly interesting.
One is of soft-gluon-pole matrix elements, another is of soft-quark-pole matrix
elements. From our results the evolutions in the two cases can be obtained. A
comparison with existing results of soft-gluon-pole matrix elements is made.
|
[
{
"created": "Thu, 3 May 2012 04:20:40 GMT",
"version": "v1"
},
{
"created": "Wed, 9 May 2012 01:09:25 GMT",
"version": "v2"
}
] |
2015-06-05
|
[
[
"Ma",
"J. P.",
""
],
[
"Wang",
"Q.",
""
]
] |
We derive the scale dependence of twist-3 quark-gluon operators, or ETQS matrix elements, at one-loop. These operators are used to factorize transverse single spin asymmetries, which are studied intensively both in experiment and theory. The scale dependence of two special cases are particularly interesting. One is of soft-gluon-pole matrix elements, another is of soft-quark-pole matrix elements. From our results the evolutions in the two cases can be obtained. A comparison with existing results of soft-gluon-pole matrix elements is made.
|
1312.2014
|
Aneesh Manohar
|
Rodrigo Alonso, Elizabeth E. Jenkins, Aneesh V. Manohar and Michael
Trott
|
Renormalization Group Evolution of the Standard Model Dimension Six
Operators III: Gauge Coupling Dependence and Phenomenology
|
28 pages + appendices v5: Minor corrections. The complete SMEFT RGE
will be maintained at http://einstein.ucsd.edu/smeft/
| null |
10.1007/JHEP04(2014)159
|
CERN-PH-TH/2013-305
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We calculate the gauge terms of the one-loop anomalous dimension matrix for
the dimension-six operators of the Standard Model effective field theory (SM
EFT). Combining these results with our previous results for the $\lambda$ and
Yukawa coupling terms completes the calculation of the one-loop anomalous
dimension matrix for the dimension-six operators. There are 1350 $CP$-even and
$1149$ $CP$-odd parameters in the dimension-six Lagrangian for 3 generations,
and our results give the entire $2499 \times 2499$ anomalous dimension matrix.
We discuss how the renormalization of the dimension-six operators, and the
additional renormalization of the dimension $d \le 4$ terms of the SM
Lagrangian due to dimension-six operators, lays the groundwork for future
precision studies of the SM EFT aimed at constraining the effects of new
physics through precision measurements at the electroweak scale. As some sample
applications, we discuss some aspects of the full RGE improved result for
essential processes such as $gg \to h$, $h \to \gamma \gamma$ and $h \to Z
\gamma$, for Higgs couplings to fermions, for the precision electroweak
parameters $S$ and $T$, and for the operators that modify important processes
in precision electroweak phenomenology, such as the three-body Higgs boson
decay $h \rightarrow Z \, \ell^+ \, \ell^-$ and triple gauge boson couplings.
We discuss how the renormalization group improved results can be used to study
the flavor problem in the SM EFT, and to test the minimal flavor violation
(MFV) hypothesis. We briefly discuss the renormalization effects on the dipole
coefficient $C_{e\gamma}$ which contributes to $\mu \to e \gamma$ and to the
muon and electron magnetic and electric dipole moments.
|
[
{
"created": "Fri, 6 Dec 2013 21:09:00 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Apr 2014 12:03:00 GMT",
"version": "v2"
},
{
"created": "Mon, 27 Jul 2015 12:54:42 GMT",
"version": "v3"
},
{
"created": "Wed, 15 Jul 2020 12:41:28 GMT",
"version": "v4"
},
{
"created": "Thu, 13 Jun 2024 16:23:18 GMT",
"version": "v5"
}
] |
2024-06-14
|
[
[
"Alonso",
"Rodrigo",
""
],
[
"Jenkins",
"Elizabeth E.",
""
],
[
"Manohar",
"Aneesh V.",
""
],
[
"Trott",
"Michael",
""
]
] |
We calculate the gauge terms of the one-loop anomalous dimension matrix for the dimension-six operators of the Standard Model effective field theory (SM EFT). Combining these results with our previous results for the $\lambda$ and Yukawa coupling terms completes the calculation of the one-loop anomalous dimension matrix for the dimension-six operators. There are 1350 $CP$-even and $1149$ $CP$-odd parameters in the dimension-six Lagrangian for 3 generations, and our results give the entire $2499 \times 2499$ anomalous dimension matrix. We discuss how the renormalization of the dimension-six operators, and the additional renormalization of the dimension $d \le 4$ terms of the SM Lagrangian due to dimension-six operators, lays the groundwork for future precision studies of the SM EFT aimed at constraining the effects of new physics through precision measurements at the electroweak scale. As some sample applications, we discuss some aspects of the full RGE improved result for essential processes such as $gg \to h$, $h \to \gamma \gamma$ and $h \to Z \gamma$, for Higgs couplings to fermions, for the precision electroweak parameters $S$ and $T$, and for the operators that modify important processes in precision electroweak phenomenology, such as the three-body Higgs boson decay $h \rightarrow Z \, \ell^+ \, \ell^-$ and triple gauge boson couplings. We discuss how the renormalization group improved results can be used to study the flavor problem in the SM EFT, and to test the minimal flavor violation (MFV) hypothesis. We briefly discuss the renormalization effects on the dipole coefficient $C_{e\gamma}$ which contributes to $\mu \to e \gamma$ and to the muon and electron magnetic and electric dipole moments.
|
1511.00549
|
David Heymes
|
Michal Czakon, David Heymes and Alexander Mitov
|
High-precision differential predictions for top-quark pairs at the LHC
|
Updated version matching the version published in PRL. Data files
with all results attached
|
Phys. Rev. Lett. 116, 082003 (2016)
|
10.1103/PhysRevLett.116.082003
|
Cavendish-HEP-15/10, TTK-15-34
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present the first complete next-to-next-to-leading order (NNLO) QCD
predictions for differential distributions in the top-quark pair production
process at the LHC. Our results are derived from a fully differential partonic
Monte Carlo calculation with stable top quarks which involves no approximations
beyond the fixed-order truncation of the perturbation series. The NNLO
corrections improve the agreement between existing LHC measurements [V.
Khachatryan et al. (CMS Collaboration), Eur. Phys. J. C 75, 542 (2015)] and
standard model predictions for the top-quark transverse momentum distribution,
thus helping alleviate one long-standing discrepancy. The shape of the
top-quark pair invariant mass distribution turns out to be stable with respect
to radiative corrections beyond NLO which increases the value of this
observable as a place to search for physics beyond the standard model. The
results presented here provide essential input for parton distribution function
fits, implementation of higher-order effects in Monte Carlo generators as well
as top-quark mass and strong coupling determination.
|
[
{
"created": "Mon, 2 Nov 2015 15:31:56 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Mar 2016 11:02:01 GMT",
"version": "v2"
}
] |
2016-03-17
|
[
[
"Czakon",
"Michal",
""
],
[
"Heymes",
"David",
""
],
[
"Mitov",
"Alexander",
""
]
] |
We present the first complete next-to-next-to-leading order (NNLO) QCD predictions for differential distributions in the top-quark pair production process at the LHC. Our results are derived from a fully differential partonic Monte Carlo calculation with stable top quarks which involves no approximations beyond the fixed-order truncation of the perturbation series. The NNLO corrections improve the agreement between existing LHC measurements [V. Khachatryan et al. (CMS Collaboration), Eur. Phys. J. C 75, 542 (2015)] and standard model predictions for the top-quark transverse momentum distribution, thus helping alleviate one long-standing discrepancy. The shape of the top-quark pair invariant mass distribution turns out to be stable with respect to radiative corrections beyond NLO which increases the value of this observable as a place to search for physics beyond the standard model. The results presented here provide essential input for parton distribution function fits, implementation of higher-order effects in Monte Carlo generators as well as top-quark mass and strong coupling determination.
|
hep-ph/0409180
|
Ryutin Roman
|
V.A. Petrov, R.A. Ryutin, A.E. Sobol (IHEP, Protvino) and J.-P.
Guillaud (LAPP, Annecy)
|
EDDE Monte Carlo event generator
|
LaTeX, 7 pages, 3 figures
| null | null | null |
hep-ph
| null |
EDDE is a Monte Carlo event generator, under construction, for different
Exclusive Double Diffractive Events. The program is based on the extended
Regge-eikonal approach for "soft" processes. Standard Model and its extensions
are used for "hard" fusion processes. An interface to PYTHIA, CMSJET and CMKIN
is provided.
|
[
{
"created": "Wed, 15 Sep 2004 13:11:03 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Sep 2005 13:09:56 GMT",
"version": "v2"
}
] |
2007-05-23
|
[
[
"Petrov",
"V. A.",
"",
"IHEP, Protvino"
],
[
"Ryutin",
"R. A.",
"",
"IHEP, Protvino"
],
[
"Sobol",
"A. E.",
"",
"IHEP, Protvino"
],
[
"Guillaud",
"J. -P.",
"",
"LAPP, Annecy"
]
] |
EDDE is a Monte Carlo event generator, under construction, for different Exclusive Double Diffractive Events. The program is based on the extended Regge-eikonal approach for "soft" processes. Standard Model and its extensions are used for "hard" fusion processes. An interface to PYTHIA, CMSJET and CMKIN is provided.
|
hep-ph/0111352
|
Edward Shuryak
|
E.V. Shuryak and A.R.Zhitnitsky
|
Domain Wall Bubbles in High Energy Heavy Ion Collisions
|
6 pages, 1 fig
|
Phys.Rev. C66 (2002) 034905
|
10.1103/PhysRevC.66.034905
| null |
hep-ph
| null |
It has been recently shown that meta-stable domain walls exist in
high-density QCD ($\mu\neq 0$) as well as in QCD with large number of colors
($N_c\to\infty$), with the lifetime being exponentially long in both cases.
Such metastable domain walls may exist in our world as well, especially in hot
hadronic matter with temperature close to critical. In this paper we discuss
what happens if a bubble made of such wall is created in heavy ion collisions,
in the mixed phase between QGP and hadronic matter. We show it will further be
expanded to larger volume $\sim 20 fm^3$ by the pion pressure, before it
disappears, either by puncture or contraction. Both scenarios leave distinctive
experimental signatures of such events, negatively affecting the interference
correlations between the outgoing pions.
|
[
{
"created": "Tue, 27 Nov 2001 17:03:09 GMT",
"version": "v1"
}
] |
2009-11-07
|
[
[
"Shuryak",
"E. V.",
""
],
[
"Zhitnitsky",
"A. R.",
""
]
] |
It has been recently shown that meta-stable domain walls exist in high-density QCD ($\mu\neq 0$) as well as in QCD with large number of colors ($N_c\to\infty$), with the lifetime being exponentially long in both cases. Such metastable domain walls may exist in our world as well, especially in hot hadronic matter with temperature close to critical. In this paper we discuss what happens if a bubble made of such wall is created in heavy ion collisions, in the mixed phase between QGP and hadronic matter. We show it will further be expanded to larger volume $\sim 20 fm^3$ by the pion pressure, before it disappears, either by puncture or contraction. Both scenarios leave distinctive experimental signatures of such events, negatively affecting the interference correlations between the outgoing pions.
|
2205.09870
|
Claudia Rella
|
Claudia Rella, Babette D\"obrich, Tien-Tien Yu
|
Searching for Muonphilic Dark Sectors with Proton Beams
|
15 pages, 8 figures, corrected typos, added references
|
Phys. Rev. D 106 (2022) 3, 035023
|
10.1103/PhysRevD.106.035023
| null |
hep-ph hep-ex
|
http://creativecommons.org/licenses/by-sa/4.0/
|
Proton beam-dump experiments are a high-intensity source of secondary muons
and provide an opportunity to probe muon-specific dark sectors. We adopt a
simplified-models framework for an exotic light scalar particle coupling
predominantly or exclusively to muons. Equipped with state-of-the-art muon
simulations, we compute the sensitivity reach in the parameter space $(m_S, \,
g_\mu)$ of the dark mediator, examining in detail the examples of the
experiment NA62 in beam-dump mode and the proposed experiment SHiP. We find a
significant yield of such exotics in the sub-GeV mass range. Our projections
are competitive with those of primary muon-beam experiments and complementary
to current constraints, spanning uncharted parameter space and accessing new
physics potentially responsible for the $(g-2)_\mu$ anomaly.
|
[
{
"created": "Thu, 19 May 2022 21:30:51 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Mar 2024 09:28:16 GMT",
"version": "v2"
}
] |
2024-03-22
|
[
[
"Rella",
"Claudia",
""
],
[
"Döbrich",
"Babette",
""
],
[
"Yu",
"Tien-Tien",
""
]
] |
Proton beam-dump experiments are a high-intensity source of secondary muons and provide an opportunity to probe muon-specific dark sectors. We adopt a simplified-models framework for an exotic light scalar particle coupling predominantly or exclusively to muons. Equipped with state-of-the-art muon simulations, we compute the sensitivity reach in the parameter space $(m_S, \, g_\mu)$ of the dark mediator, examining in detail the examples of the experiment NA62 in beam-dump mode and the proposed experiment SHiP. We find a significant yield of such exotics in the sub-GeV mass range. Our projections are competitive with those of primary muon-beam experiments and complementary to current constraints, spanning uncharted parameter space and accessing new physics potentially responsible for the $(g-2)_\mu$ anomaly.
|
hep-ph/9411361
| null |
Stefano Catani (INFN Firenze)
|
Jet Physics at LEP and SLC
|
32 pages (+14 figs. available in hard copy upon request to
[email protected]), LateX
| null | null |
DFF 211/10/94
|
hep-ph
| null |
Experimental results on jet physics at LEP and SLC are reviewed and compared
with perturbative QCD predictions. The discussion includes determinations of
the strong coupling $\as$, measurements of event shape distributions and jet
cross sections, studies of subjet multiplicities and tests of QCD coherence.
|
[
{
"created": "Tue, 22 Nov 1994 16:41:30 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Catani",
"Stefano",
"",
"INFN Firenze"
]
] |
Experimental results on jet physics at LEP and SLC are reviewed and compared with perturbative QCD predictions. The discussion includes determinations of the strong coupling $\as$, measurements of event shape distributions and jet cross sections, studies of subjet multiplicities and tests of QCD coherence.
|
2204.11121
|
Elsayed Elmaghraby Prof. Dr.
|
Elsayed K. Elmaghraby
|
Configuration mixing in particle decay and reaction
|
7 pages, 2 figures, 46 references, published in Prog. Phys. 13, 150
(2017)
|
Prog. Phys. 13, 150 (2017)
| null | null |
hep-ph
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
Background: Decay constants of unstable nuclei and particles are quantum
constants. Recent controversy on the existence (versus non-existence) of
variability in the observation of decay rate can be settled by considering
mixing in decay configuration. Purpose: Variability in decay rate was
investigated based on the available information of beta decay rate data, solar
neutrino flux, and energy distribution. Method: Full systematic analysis of the
oscillatory behavior was carried out. Based on the zero threshold energy for
neutrino absorption in beta emitters, a model for configuration mixing between
two distinct beta disintegration modes $\beta^\nu$-disintegration (electron
from neutrino interaction) and the $\beta^-$-disintegration (electron from
natural decay) was proposed. Results: The phenomenon of variability in beta
decay rate was related to the possible exothermic neutrino absorption by
unstable nuclei which, in principle, should include the whole range of flux
energies involving flux with energy below the $^{71}$Ga threshold at 0.23 MeV.
These two disintegration modes occur independently and model for their apparent
mixing rate was proposed. Conclusions: The configuration mixing between the two
modes causes depletion of radioactive nuclei which is subject to change with
seasonal solar neutrino variability. Ability to detect this variability was
found to be dependent on the Q-value of the $\beta^\nu$ disintegration and
detection instrument setup. Value of neutrino cross section weighted by the
ratio between $\beta^\nu$ and $\beta^-$ detection efficiencies was found to be
in the range $10^{-44}$ to $10^{-36}$ cm$^{2}$. For experiments that uses the
end point to determine the neutrino mass, interference due to mixing should be
taken into account.
|
[
{
"created": "Sat, 23 Apr 2022 18:49:55 GMT",
"version": "v1"
}
] |
2022-04-26
|
[
[
"Elmaghraby",
"Elsayed K.",
""
]
] |
Background: Decay constants of unstable nuclei and particles are quantum constants. Recent controversy on the existence (versus non-existence) of variability in the observation of decay rate can be settled by considering mixing in decay configuration. Purpose: Variability in decay rate was investigated based on the available information of beta decay rate data, solar neutrino flux, and energy distribution. Method: Full systematic analysis of the oscillatory behavior was carried out. Based on the zero threshold energy for neutrino absorption in beta emitters, a model for configuration mixing between two distinct beta disintegration modes $\beta^\nu$-disintegration (electron from neutrino interaction) and the $\beta^-$-disintegration (electron from natural decay) was proposed. Results: The phenomenon of variability in beta decay rate was related to the possible exothermic neutrino absorption by unstable nuclei which, in principle, should include the whole range of flux energies involving flux with energy below the $^{71}$Ga threshold at 0.23 MeV. These two disintegration modes occur independently and model for their apparent mixing rate was proposed. Conclusions: The configuration mixing between the two modes causes depletion of radioactive nuclei which is subject to change with seasonal solar neutrino variability. Ability to detect this variability was found to be dependent on the Q-value of the $\beta^\nu$ disintegration and detection instrument setup. Value of neutrino cross section weighted by the ratio between $\beta^\nu$ and $\beta^-$ detection efficiencies was found to be in the range $10^{-44}$ to $10^{-36}$ cm$^{2}$. For experiments that uses the end point to determine the neutrino mass, interference due to mixing should be taken into account.
|
hep-ph/0702204
|
Vittorio Lubicz
|
Vittorio Lubicz
|
Lattice QCD, Flavor Physics and the Unitarity Triangle Analysis
|
Contribution to the proceedings of HQL06, Munich, October 16th-20th
2006. 11 pages
|
ECONFC0610161:029,2006
| null |
RM3-TH/07-4
|
hep-ph
| null |
Lattice QCD has always played a relevant role in the studies of flavor
physics and, in particular, in the Unitarity Triangle (UT) analysis. Before the
starting of the B factories, this analysis relied on the results of lattice QCD
simulations to relate the experimental determinations of semileptonic B decays,
K-Kbar and B_{d,s}-B_{d,s}bar mixing to the CKM parameters. In the last years
much more information has been obtained from the direct determination of the UT
angles from non-leptonic B decays. In this talk, after a presentation of recent
averages of lattice QCD results, we compare the outcome of the "classical" UT
analysis (UTlattice) with the analysis based on the angles determinations
(UTangles). We discuss the role of the different determinations of Vub, and
show that current data do not favour the value measured in inclusive decays.
Finally we show that the recent measurement of Delta ms, combined with Delta md
and epsilonK, allows a quite accurate extraction of the values of the hadronic
parameters, BK, fBs*sqrt(B_Bs) and xi. These values, obtained "experimentally"
by assuming the validity of the Standard Model, are compared with the
theoretical predictions from lattice QCD.
|
[
{
"created": "Tue, 20 Feb 2007 16:34:23 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Lubicz",
"Vittorio",
""
]
] |
Lattice QCD has always played a relevant role in the studies of flavor physics and, in particular, in the Unitarity Triangle (UT) analysis. Before the starting of the B factories, this analysis relied on the results of lattice QCD simulations to relate the experimental determinations of semileptonic B decays, K-Kbar and B_{d,s}-B_{d,s}bar mixing to the CKM parameters. In the last years much more information has been obtained from the direct determination of the UT angles from non-leptonic B decays. In this talk, after a presentation of recent averages of lattice QCD results, we compare the outcome of the "classical" UT analysis (UTlattice) with the analysis based on the angles determinations (UTangles). We discuss the role of the different determinations of Vub, and show that current data do not favour the value measured in inclusive decays. Finally we show that the recent measurement of Delta ms, combined with Delta md and epsilonK, allows a quite accurate extraction of the values of the hadronic parameters, BK, fBs*sqrt(B_Bs) and xi. These values, obtained "experimentally" by assuming the validity of the Standard Model, are compared with the theoretical predictions from lattice QCD.
|
hep-ph/9605289
|
Toshiaki Ito
|
Toshiaki Ito and Yoshimitsu Matsui (Nagoya University)
|
The \Xi_Q - \Xi_Q' Mixing and Heavy Baryon Masses
|
8 pages LaTeX
|
Prog.Theor.Phys. 96 (1996) 659-664
|
10.1143/PTP.96.659
|
DPNU-96-26
|
hep-ph
| null |
We examine the $\Xi_Q - \Xi'_Q$ mixing and heavy baryon masses in the heavy
quark effective theory with the $\mq$ corrections. In the conventional baryon
assignment, we obtain the mixing angle $\cos^2 \theta = 0.87\pm 0.03$ in virtue
of the Gell-Mann-Okubo mass relation. On the other hand, if we adopt the new
baryon assignment given by Falk, the allowed region of the $\Sigma_c$ mass is
upper from 2372 MeV.
|
[
{
"created": "Mon, 13 May 1996 04:08:28 GMT",
"version": "v1"
},
{
"created": "Mon, 20 May 1996 03:16:18 GMT",
"version": "v2"
},
{
"created": "Thu, 26 Sep 1996 08:06:27 GMT",
"version": "v3"
}
] |
2016-09-01
|
[
[
"Ito",
"Toshiaki",
"",
"Nagoya University"
],
[
"Matsui",
"Yoshimitsu",
"",
"Nagoya University"
]
] |
We examine the $\Xi_Q - \Xi'_Q$ mixing and heavy baryon masses in the heavy quark effective theory with the $\mq$ corrections. In the conventional baryon assignment, we obtain the mixing angle $\cos^2 \theta = 0.87\pm 0.03$ in virtue of the Gell-Mann-Okubo mass relation. On the other hand, if we adopt the new baryon assignment given by Falk, the allowed region of the $\Sigma_c$ mass is upper from 2372 MeV.
|
2107.10748
|
Ralf-Arno Tripolt
|
Christopher Jung, Jan-Hendrik Otto, Ralf-Arno Tripolt, Lorenz von
Smekal
|
Self-consistent $O(4)$ model spectral functions from analytically
continued FRG flows
|
21 pages, 16 figures v2: minor changes, agrees with published version
| null |
10.1103/PhysRevD.104.094011
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this paper we explore practicable ways for self-consistent calculations of
spectral functions from analytically continued functional renormalization group
(aFRG) flow equations. As a particularly straightforward one we propose to
include parametrizations of self-energies based on explicit analytic one-loop
expressions. To exemplify this scheme we calculate the spectral functions of
pion and sigma meson of the $O(4)$ model at vanishing temperature in the broken
phase. Comparing the results with those from previous aFRG calculations, we
explicitly demonstrate how self-consistency at all momenta fixes the tight
relation between particle masses and decay thresholds. In addition, the
two-point functions from our new semi-analytic FRG scheme have the desired
domain of holomorphy built in and can readily be studied in the entire
cut-complex frequency plane, on physical as well as other Riemann sheets. This
is very illustrative and allows, for example, to trace the flow of the
resonance pole of the sigma meson across an unphysical sheet. In order to
assess the limitations due to the underlying one-loop structure, we also
introduce a fully self-consistent numerical scheme based on spectral
representations with scale-dependent spectral functions. The most notable
improvement of this numerically involved calculation is that it describes the
three-particle resonance decay of an off-shell pion, $\pi^* \to
\sigma\pi\to3\pi$. Apart from this further conceptual improvement, overall
agreement with the results from the considerably simpler semi-analytic one-loop
scheme is very encouraging, however. The latter can therefore provide a sound
and practicable basis for self-consistent calculations of spectral functions in
more realistic effective theories for warm and dense matter.
|
[
{
"created": "Thu, 22 Jul 2021 15:33:33 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Oct 2021 09:57:09 GMT",
"version": "v2"
}
] |
2021-11-24
|
[
[
"Jung",
"Christopher",
""
],
[
"Otto",
"Jan-Hendrik",
""
],
[
"Tripolt",
"Ralf-Arno",
""
],
[
"von Smekal",
"Lorenz",
""
]
] |
In this paper we explore practicable ways for self-consistent calculations of spectral functions from analytically continued functional renormalization group (aFRG) flow equations. As a particularly straightforward one we propose to include parametrizations of self-energies based on explicit analytic one-loop expressions. To exemplify this scheme we calculate the spectral functions of pion and sigma meson of the $O(4)$ model at vanishing temperature in the broken phase. Comparing the results with those from previous aFRG calculations, we explicitly demonstrate how self-consistency at all momenta fixes the tight relation between particle masses and decay thresholds. In addition, the two-point functions from our new semi-analytic FRG scheme have the desired domain of holomorphy built in and can readily be studied in the entire cut-complex frequency plane, on physical as well as other Riemann sheets. This is very illustrative and allows, for example, to trace the flow of the resonance pole of the sigma meson across an unphysical sheet. In order to assess the limitations due to the underlying one-loop structure, we also introduce a fully self-consistent numerical scheme based on spectral representations with scale-dependent spectral functions. The most notable improvement of this numerically involved calculation is that it describes the three-particle resonance decay of an off-shell pion, $\pi^* \to \sigma\pi\to3\pi$. Apart from this further conceptual improvement, overall agreement with the results from the considerably simpler semi-analytic one-loop scheme is very encouraging, however. The latter can therefore provide a sound and practicable basis for self-consistent calculations of spectral functions in more realistic effective theories for warm and dense matter.
|
1910.06158
|
Robert Ehrlich
|
Robert Ehrlich
|
First results of the KATRIN neutrino mass experiment and their
consistency with an exotic $3+3$ model
| null | null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Although the first results of the KATRIN neutrino mass experiment are
consistent with a new improved upper limit of 1.1 eV for the effective mass of
the electron neutrino, surprisingly they are also consistent with an exotic
model of the neutrino masses put forward in 2013 that includes one tachyonic
mass state doublet having $m^2\sim - 0.2$ keV$^2$. A definitive conclusion on
the validity of the model should be possible after less than one year of KATRIN
data-taking.
|
[
{
"created": "Mon, 14 Oct 2019 14:11:21 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Oct 2019 12:53:08 GMT",
"version": "v2"
},
{
"created": "Tue, 22 Oct 2019 14:47:58 GMT",
"version": "v3"
},
{
"created": "Wed, 23 Oct 2019 16:29:04 GMT",
"version": "v4"
},
{
"created": "Mon, 28 Oct 2019 15:55:56 GMT",
"version": "v5"
},
{
"created": "Thu, 31 Oct 2019 14:15:15 GMT",
"version": "v6"
},
{
"created": "Mon, 6 Jan 2020 17:34:31 GMT",
"version": "v7"
},
{
"created": "Wed, 8 Jan 2020 13:34:13 GMT",
"version": "v8"
},
{
"created": "Mon, 9 Aug 2021 23:10:54 GMT",
"version": "v9"
}
] |
2021-08-11
|
[
[
"Ehrlich",
"Robert",
""
]
] |
Although the first results of the KATRIN neutrino mass experiment are consistent with a new improved upper limit of 1.1 eV for the effective mass of the electron neutrino, surprisingly they are also consistent with an exotic model of the neutrino masses put forward in 2013 that includes one tachyonic mass state doublet having $m^2\sim - 0.2$ keV$^2$. A definitive conclusion on the validity of the model should be possible after less than one year of KATRIN data-taking.
|
hep-ph/0406036
|
Chun-Khiang Chua
|
Hai-Yang Cheng and Chun-Khiang Chua
|
Light-Front Approach for Pentaquark Strong Decays
|
24 pages, 2 figures
|
JHEP0411:072,2004
|
10.1088/1126-6708/2004/11/072
| null |
hep-ph
| null |
Assuming the two diquark structure for the pentaquark state as advocated in
the Jaffe-Wilczek model, we study the strong decays of light and heavy
parity-even pentaquark states using the light-front quark model in conjunction
with the spectator approximation. The narrowness of the Theta width is ascribed
to the p-wave configuration of the diquark pair. Taking the Theta width as a
benchmark, we estimate the rates of the strong decays Xi_{3/2}-- to Xi- pi-,
Sigma- K-, Sigma_{5c}0 to D_s- p, D_{s0}*- p and Xi_{5c}0 to D_s- Sigma+,
D_{s0}^{*-} Sigma+ with Sigma_{5c} Xi_{5c} being antisextet charmed pentaquarks
and D_{s0}* a scalar strange charmed meson. The ratio of Gamma(P_c to Baryon
D_{s0}*)/Gamma(P_c to Baryon D_s) is very useful for verifying the parity of
the antisextet charmed pentaquark P_c. It is expected to be of order unity for
an even parity P_c and much less than one for an odd parity pentaquark.
|
[
{
"created": "Thu, 3 Jun 2004 08:35:31 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Cheng",
"Hai-Yang",
""
],
[
"Chua",
"Chun-Khiang",
""
]
] |
Assuming the two diquark structure for the pentaquark state as advocated in the Jaffe-Wilczek model, we study the strong decays of light and heavy parity-even pentaquark states using the light-front quark model in conjunction with the spectator approximation. The narrowness of the Theta width is ascribed to the p-wave configuration of the diquark pair. Taking the Theta width as a benchmark, we estimate the rates of the strong decays Xi_{3/2}-- to Xi- pi-, Sigma- K-, Sigma_{5c}0 to D_s- p, D_{s0}*- p and Xi_{5c}0 to D_s- Sigma+, D_{s0}^{*-} Sigma+ with Sigma_{5c} Xi_{5c} being antisextet charmed pentaquarks and D_{s0}* a scalar strange charmed meson. The ratio of Gamma(P_c to Baryon D_{s0}*)/Gamma(P_c to Baryon D_s) is very useful for verifying the parity of the antisextet charmed pentaquark P_c. It is expected to be of order unity for an even parity P_c and much less than one for an odd parity pentaquark.
|
hep-ph/0112035
|
Cosmin Macesanu
|
Cosmin Macesanu
|
The Top Quark at Linear Colliders: QCD Corrections
|
Ph. D. thesis, 110 pages, 18 figures
| null | null | null |
hep-ph
| null |
We present a computation of QCD next-to-leading order corrections to the top
production and decay process at linear colliders. The top quarks are allowed to
be off-shell and the production and decay subprocesses are treated together,
thus allowing for interference effects. Real gluon radiation effects as well as
virtual corrections are evaluated. The framework employed for this computation
is the double pole approximation (DPA).The results discussed include studies of
the gluon radiation properties, interference between production- and decay-
stage radiation, and top mass reconstruction.
|
[
{
"created": "Mon, 3 Dec 2001 19:37:53 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Macesanu",
"Cosmin",
""
]
] |
We present a computation of QCD next-to-leading order corrections to the top production and decay process at linear colliders. The top quarks are allowed to be off-shell and the production and decay subprocesses are treated together, thus allowing for interference effects. Real gluon radiation effects as well as virtual corrections are evaluated. The framework employed for this computation is the double pole approximation (DPA).The results discussed include studies of the gluon radiation properties, interference between production- and decay- stage radiation, and top mass reconstruction.
|
hep-ph/0007065
|
Robert Foot
|
R. Foot
|
Is the $\nu_\mu --> \nu_s$ oscillation solution to the atmospheric
neutrino anomaly excluded by the superKamiokande data?
|
new improved version, 6 pages with figs
|
Phys.Lett. B496 (2000) 169-174
|
10.1016/S0370-2693(00)01290-9
| null |
hep-ph hep-ex
| null |
Recently the SuperKamiokande collaboration have claimed that their data
exclude the $\nu_\mu --> \nu_s$ solution to the atmospheric neutrino anomaly at
more than 99% C.L. We critically examine this claim.
|
[
{
"created": "Fri, 7 Jul 2000 05:36:09 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Sep 2000 06:49:32 GMT",
"version": "v2"
}
] |
2009-10-31
|
[
[
"Foot",
"R.",
""
]
] |
Recently the SuperKamiokande collaboration have claimed that their data exclude the $\nu_\mu --> \nu_s$ solution to the atmospheric neutrino anomaly at more than 99% C.L. We critically examine this claim.
|
hep-ph/9303220
| null |
P.Colangelo, G.Nardulli and N.Paver
|
QCD Sum Rules and B Decays
|
25 pages, 1 figure (not included) available upon request, TeX,
BARI-TH/92-132, UTS-UFT-93-3
| null | null | null |
hep-ph
| null |
We review some recent applications of QCD sum rules to $B$-decays. These
include the determination of the leptonic constant $f_B$ and of the
semileptonic transition amplitudes of the $B$-meson into negative and positive
parity charmed states.
|
[
{
"created": "Thu, 4 Mar 1993 13:54:00 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Colangelo",
"P.",
""
],
[
"Nardulli",
"G.",
""
],
[
"Paver",
"N.",
""
]
] |
We review some recent applications of QCD sum rules to $B$-decays. These include the determination of the leptonic constant $f_B$ and of the semileptonic transition amplitudes of the $B$-meson into negative and positive parity charmed states.
|
0909.4943
|
Hiroaki Sugiyama
|
Takeshi Fukuyama (Ritsumeikan U., Kusatsu), Hiroaki Sugiyama
(Ritsumeikan U., Kusatsu), Koji Tsumura (ICTP, Trieste)
|
Constraints from muon g-2 and LFV processes in the Higgs Triplet Model
|
18 pages, 16 figures
|
JHEP 1003:044,2010
|
10.1007/JHEP03(2010)044
|
IC/2009/076
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Constraints from the muon anomalous magnetic dipole moment and lepton flavor
violating processes are translated into lower bounds on v_Delta*m_H++ in the
Higgs Triplet Model by considering correlations through the neutrino mass
matrix. The discrepancy of the sign of the contribution to the muon anomalous
magnetic dipole moment between the measurement and the prediction in the model
is clarified. It is shown that mu to e gamma, tau decays (especially, tau to mu
e e), and the muonium conversion can give a more stringent bound on
v_Delta*m_H++ than the bound from mu to eee which is expected naively to give
the most stringent one.
|
[
{
"created": "Sun, 27 Sep 2009 15:26:43 GMT",
"version": "v1"
}
] |
2010-03-19
|
[
[
"Fukuyama",
"Takeshi",
"",
"Ritsumeikan U., Kusatsu"
],
[
"Sugiyama",
"Hiroaki",
"",
"Ritsumeikan U., Kusatsu"
],
[
"Tsumura",
"Koji",
"",
"ICTP, Trieste"
]
] |
Constraints from the muon anomalous magnetic dipole moment and lepton flavor violating processes are translated into lower bounds on v_Delta*m_H++ in the Higgs Triplet Model by considering correlations through the neutrino mass matrix. The discrepancy of the sign of the contribution to the muon anomalous magnetic dipole moment between the measurement and the prediction in the model is clarified. It is shown that mu to e gamma, tau decays (especially, tau to mu e e), and the muonium conversion can give a more stringent bound on v_Delta*m_H++ than the bound from mu to eee which is expected naively to give the most stringent one.
|
1505.04466
|
Michal Deak Dr.
|
Michal Deak
|
The role of the kinematical constraint and non-linear effects in the
CCFM equation
|
prepared for Excited QCD 2015 proceedings
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We report on recent study [1] of the role of the kinematical constraint in
the CCFM equation and its non-linear extension. We compare numerical results
obtained by solving the CCFM equation and argue that kinematical constraint
represents an important correction.
|
[
{
"created": "Sun, 17 May 2015 22:04:11 GMT",
"version": "v1"
},
{
"created": "Tue, 19 May 2015 11:05:23 GMT",
"version": "v2"
}
] |
2015-05-20
|
[
[
"Deak",
"Michal",
""
]
] |
We report on recent study [1] of the role of the kinematical constraint in the CCFM equation and its non-linear extension. We compare numerical results obtained by solving the CCFM equation and argue that kinematical constraint represents an important correction.
|
1312.3742
|
Mikhail Galynskii
|
M.V. Galynskii and E.A. Kuraev
|
Alternative way to understand the unexpected results of the JLab
polarization experiments to measure the Sachs form factors ratio
|
Version, published in Phys. Rev. D. arXiv admin note: substantial
text overlap with arXiv:1210.0634
|
Phys. Rev. D, vol. 89, iss. 5, p. 054005 (2014)
|
10.1103/PhysRevD.89.054005
| null |
hep-ph nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In the one-photon exchange approximation we discuss questions related to the
interpretation of unexpected results of the JLab polarization experiments to
measure the Sachs form factors ratio $G_E/G_M$ in the region $1. 0 \leq Q^2
\leq 8.5$ GeV$^2$. For this purpose, we developed an approach which essentially
is a generalization of the constituent-counting rules of the perturbative QCD
(pQCD) for the case of massive quarks. We assume that at the lower boundary of
the considered region the hard-scattering mechanism of pQCD is realized. Within
the framework of the developed approach we calculated the hard kernel of the
proton current matrix elements $J^{\pm \delta, \delta }_{p}$ for the full set
of spin combinations corresponding to the number of the spin-flipped quarks,
which contribute to the proton transition without spin-flip ($J^{\delta, \delta
}_{p}$) and with the spin-flip ($J^{-\delta, \delta }_{p}$). This allows us to
state that (i) around the lower boundary of the considered region, the leading
scaling behavior of the Sachs form factors has the form $G_E, G_M \sim 1/Q^6$,
(ii) the dipole dependence ($G_E, G_M \sim 1/Q^4$) is realized in the
asymptotic regime of pQCD when $\tau \gg 1$ ($\tau=Q^2/4M^2$) in the case when
the quark transitions with spin-flip dominate, (iii) the asymptotic regime of
pQCD in the JLab experiments has not yet been achieved, and (iv) the linear
decrease of the ratio $G_{E}/G_{M}$ at $\tau < 1$ is due to additional
contributions to $J^{\delta, \delta }_{p}$ by spin-flip transitions of two
quarks and an additional contribution to $J^{-\delta, \delta }_{p}$ by
spin-flip transitions of three quarks.
|
[
{
"created": "Fri, 13 Dec 2013 09:31:08 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Feb 2014 14:30:47 GMT",
"version": "v2"
},
{
"created": "Tue, 18 Mar 2014 21:37:47 GMT",
"version": "v3"
}
] |
2014-03-20
|
[
[
"Galynskii",
"M. V.",
""
],
[
"Kuraev",
"E. A.",
""
]
] |
In the one-photon exchange approximation we discuss questions related to the interpretation of unexpected results of the JLab polarization experiments to measure the Sachs form factors ratio $G_E/G_M$ in the region $1. 0 \leq Q^2 \leq 8.5$ GeV$^2$. For this purpose, we developed an approach which essentially is a generalization of the constituent-counting rules of the perturbative QCD (pQCD) for the case of massive quarks. We assume that at the lower boundary of the considered region the hard-scattering mechanism of pQCD is realized. Within the framework of the developed approach we calculated the hard kernel of the proton current matrix elements $J^{\pm \delta, \delta }_{p}$ for the full set of spin combinations corresponding to the number of the spin-flipped quarks, which contribute to the proton transition without spin-flip ($J^{\delta, \delta }_{p}$) and with the spin-flip ($J^{-\delta, \delta }_{p}$). This allows us to state that (i) around the lower boundary of the considered region, the leading scaling behavior of the Sachs form factors has the form $G_E, G_M \sim 1/Q^6$, (ii) the dipole dependence ($G_E, G_M \sim 1/Q^4$) is realized in the asymptotic regime of pQCD when $\tau \gg 1$ ($\tau=Q^2/4M^2$) in the case when the quark transitions with spin-flip dominate, (iii) the asymptotic regime of pQCD in the JLab experiments has not yet been achieved, and (iv) the linear decrease of the ratio $G_{E}/G_{M}$ at $\tau < 1$ is due to additional contributions to $J^{\delta, \delta }_{p}$ by spin-flip transitions of two quarks and an additional contribution to $J^{-\delta, \delta }_{p}$ by spin-flip transitions of three quarks.
|
hep-ph/9604344
|
Passarino Giampiero
|
Giampiero Passarino (Univ., INFN Torino)
|
LEP1 - LEP2: Theory versus Experiment
|
8 pages, 10 Postscript figures, Talk given at PADLEP 96, Padova,
April 9-11 1996 and at the One Day Meeting on Open Problems in High Energy
Physics, Frascati, April 10, 1996
| null | null | null |
hep-ph
| null |
The status of the standard model is briefly reviewed in the light of the most
recent set of experimental data, with particular emphasis to the limits on the
Higgs boson mass. The search for a light Higgs boson at LEP~2 is also briefly
analyzed.
|
[
{
"created": "Wed, 17 Apr 1996 08:59:34 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Passarino",
"Giampiero",
"",
"Univ., INFN Torino"
]
] |
The status of the standard model is briefly reviewed in the light of the most recent set of experimental data, with particular emphasis to the limits on the Higgs boson mass. The search for a light Higgs boson at LEP~2 is also briefly analyzed.
|
2003.00427
|
Takuya Mizoguchi
|
Takuya Mizoguchi and Minoru Biyajima
|
Analysis of Bose-Einstein correlation at 7 TeV by LHCb collaboration
based on stochastic approach
| null | null |
10.1142/S0217751X20500529
| null |
hep-ph hep-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The Bose-Einstein correlation (BEC) in forward region ($2.0<\eta<4.8$)
measured at 7 TeV in the Large Hadron Collider (LHC) by the LHCb collaboration
is analyzed using two conventional formulas of different types named CF$_{\rm
I}$ and CF$_{\rm II}$. The first formula is well known and contains the degree
of coherence ($\lambda$) and the exchange function $E_{\rm BE}^2$ from the BE
statistics. The second formula is an extended formula (CF$_{\rm II}$) that
contains the second degree of coherence $\lambda_2$ and the second exchange
function $E_{\rm BE_2}^2$ in addition to CF$_{\rm I}$. To examine the physical
meaning of the parameters estimated by CF$_{\rm II}$, we analyze the LHCb BEC
data by using a stochastic approach of the three-negative binomial distribution
and the three-generalized Glauber-Lachs formula. Our results reveal that the
BEC at 7 TeV consisted of three activity intervals defined by the multiplicity
$n$ ([8, 18], [19, 35], and [36, 96]) can be well explained by CF$_{\rm II}$.
|
[
{
"created": "Sun, 1 Mar 2020 07:23:25 GMT",
"version": "v1"
},
{
"created": "Tue, 31 Mar 2020 16:02:18 GMT",
"version": "v2"
}
] |
2020-05-20
|
[
[
"Mizoguchi",
"Takuya",
""
],
[
"Biyajima",
"Minoru",
""
]
] |
The Bose-Einstein correlation (BEC) in forward region ($2.0<\eta<4.8$) measured at 7 TeV in the Large Hadron Collider (LHC) by the LHCb collaboration is analyzed using two conventional formulas of different types named CF$_{\rm I}$ and CF$_{\rm II}$. The first formula is well known and contains the degree of coherence ($\lambda$) and the exchange function $E_{\rm BE}^2$ from the BE statistics. The second formula is an extended formula (CF$_{\rm II}$) that contains the second degree of coherence $\lambda_2$ and the second exchange function $E_{\rm BE_2}^2$ in addition to CF$_{\rm I}$. To examine the physical meaning of the parameters estimated by CF$_{\rm II}$, we analyze the LHCb BEC data by using a stochastic approach of the three-negative binomial distribution and the three-generalized Glauber-Lachs formula. Our results reveal that the BEC at 7 TeV consisted of three activity intervals defined by the multiplicity $n$ ([8, 18], [19, 35], and [36, 96]) can be well explained by CF$_{\rm II}$.
|
hep-ph/0102274
|
Manmohan Gupta
|
Monika Randhawa and Manmohan Gupta
|
Constructing "Reference" Triangle through Unitarity of CKM Matrix
|
Latex, 10 pages, 1 eps figure
| null | null | null |
hep-ph
| null |
Motivated by the possibility of the low value of sin2\beta in the
measurements of BABAR and BELLE collaborations, a reference unitarity triangle
is constructed using the unitarity of the CKM matrix and the experimental
values of the well known CKM elements, without involving any inputs from the
processes which might include the new physics effects. The angles of the
triangle are evaluated by finding the CP violating phase \delta through the
Jarlskog's rephasing invariant parameter J. The present data and the unitarity
of the CKM matrix gives for \delta the range 28^o to 152^o, which for sin2\beta
translates to the range 0.21 to 0.88. This range is broadly in agreement with
the recent BABAR and BELLE results. However, a value of sin2\beta \leq 0.2,
advocated by Silva and Wolfenstein as a benchmark for new physics, would imply
a violation in the three generation unitarity and would hint towards the
existence of a fourth generation Further, the future refinements in the CKM
elements will push the lower limit on sin2\beta still higher.
|
[
{
"created": "Thu, 22 Feb 2001 11:04:39 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Randhawa",
"Monika",
""
],
[
"Gupta",
"Manmohan",
""
]
] |
Motivated by the possibility of the low value of sin2\beta in the measurements of BABAR and BELLE collaborations, a reference unitarity triangle is constructed using the unitarity of the CKM matrix and the experimental values of the well known CKM elements, without involving any inputs from the processes which might include the new physics effects. The angles of the triangle are evaluated by finding the CP violating phase \delta through the Jarlskog's rephasing invariant parameter J. The present data and the unitarity of the CKM matrix gives for \delta the range 28^o to 152^o, which for sin2\beta translates to the range 0.21 to 0.88. This range is broadly in agreement with the recent BABAR and BELLE results. However, a value of sin2\beta \leq 0.2, advocated by Silva and Wolfenstein as a benchmark for new physics, would imply a violation in the three generation unitarity and would hint towards the existence of a fourth generation Further, the future refinements in the CKM elements will push the lower limit on sin2\beta still higher.
|
2204.10173
|
Jonathan Mo
|
X. Chen, T. Gehrmann, E.W.N. Glover, A. Huss, J. Mo
|
NNLO QCD corrections in full colour for jet production observables at
the LHC
|
31 pages, 16 figures, data for figures included as auxiliary files
| null |
10.1007/JHEP09(2022)025
|
ZU-TH 11/22, KA-TP-07-2022, IPPP/22/20, P3H-22-037, CERN-TH-2022-067
|
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
Calculations for processes involving a high multiplicity of coloured
particles often employ a leading colour approximation, where only the leading
terms in the expansion of the number of colours $N_c$ and the number of
flavours $n_f$ are retained. This approximation of the full colour result is
motivated by the $1/N_c^2$ suppression of the first subleading terms and by the
increasing complexity of including subleading colour contributions to the
calculation. In this work, we present the calculations using the antenna
subtraction method in the NNLOJET framework for the NNLO QCD corrections at
full colour for several jet observables at the LHC. The single jet inclusive
cross section is calculated doubly differential in transverse momentum and
absolute rapidity and compared with the CMS measurement at 13 TeV. A
calculation for dijet production doubly differential in dijet mass and rapidity
difference is also performed and compared with the ATLAS 7 TeV data. Lastly, a
triply differential dijet cross section in average transverse momentum,
rapidity separation and dijet system boost is calculated and compared with the
CMS 8 TeV data. The impact of the subleading colour contributions to the
leading colour approximation is assessed in detail for all three types of
observables and as a function of the jet cone size. The subleading colour
contributions play a potentially sizable role in the description of the triply
differential distributions, which probe kinematical configurations that are not
easily accessed by any of the other observables.
|
[
{
"created": "Thu, 21 Apr 2022 15:34:33 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Sep 2022 19:22:43 GMT",
"version": "v2"
}
] |
2022-09-21
|
[
[
"Chen",
"X.",
""
],
[
"Gehrmann",
"T.",
""
],
[
"Glover",
"E. W. N.",
""
],
[
"Huss",
"A.",
""
],
[
"Mo",
"J.",
""
]
] |
Calculations for processes involving a high multiplicity of coloured particles often employ a leading colour approximation, where only the leading terms in the expansion of the number of colours $N_c$ and the number of flavours $n_f$ are retained. This approximation of the full colour result is motivated by the $1/N_c^2$ suppression of the first subleading terms and by the increasing complexity of including subleading colour contributions to the calculation. In this work, we present the calculations using the antenna subtraction method in the NNLOJET framework for the NNLO QCD corrections at full colour for several jet observables at the LHC. The single jet inclusive cross section is calculated doubly differential in transverse momentum and absolute rapidity and compared with the CMS measurement at 13 TeV. A calculation for dijet production doubly differential in dijet mass and rapidity difference is also performed and compared with the ATLAS 7 TeV data. Lastly, a triply differential dijet cross section in average transverse momentum, rapidity separation and dijet system boost is calculated and compared with the CMS 8 TeV data. The impact of the subleading colour contributions to the leading colour approximation is assessed in detail for all three types of observables and as a function of the jet cone size. The subleading colour contributions play a potentially sizable role in the description of the triply differential distributions, which probe kinematical configurations that are not easily accessed by any of the other observables.
|
1506.03360
|
Alfredo Urbano
|
Luigi Delle Rose, Carlo Marzo, Alfredo Urbano
|
On the stability of the electroweak vacuum in the presence of low-scale
seesaw models
|
32 pages, 9 figures. Minor changes, references added
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The scale of neutrino masses and the Planck scale are separated by more than
twenty-seven order of magnitudes. However, they can be linked by imposing the
stability of the electroweak (EW) vacuum. The crucial ingredient is provided by
the generation of neutrino masses via a seesaw mechanism triggered by Yukawa
interactions between the standard model (SM) Higgs and lepton doublets and
additional heavy right-handed neutrinos. These neutrinos participate to the
renormalization group (RG) running of the dimensionless SM couplings, affecting
their high-energy behavior. The Higgs quartic coupling is dragged towards
negative values, thus altering the stability of the EW vacuum. In the usual
type-I seesaw model, this effect is too small to be a threat since, in order to
comply with low-energy neutrino data, one is forced to consider either too
small Yukawa couplings or too heavy right-handed neutrinos. In this paper we
explore this general idea in the context of low-scale seesaw models. These
models are characterized by sizable Yukawa couplings and right-handed neutrinos
with mass of the order of the EW scale, thus maximizing their impact on the RG
flow. As a general result, we find that Yukawa couplings such that ${\rm
Tr}(Y_{\nu}^{\dag}Y_{\nu}) \gtrsim 0.4$ are excluded. We discuss the impact of
this bound on several observables, with a special focus on the lepton flavor
violating process $\mu\to e\gamma$ and the neutrino-less double beta decay.
|
[
{
"created": "Wed, 10 Jun 2015 15:25:35 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Jun 2015 20:23:58 GMT",
"version": "v2"
}
] |
2015-06-18
|
[
[
"Rose",
"Luigi Delle",
""
],
[
"Marzo",
"Carlo",
""
],
[
"Urbano",
"Alfredo",
""
]
] |
The scale of neutrino masses and the Planck scale are separated by more than twenty-seven order of magnitudes. However, they can be linked by imposing the stability of the electroweak (EW) vacuum. The crucial ingredient is provided by the generation of neutrino masses via a seesaw mechanism triggered by Yukawa interactions between the standard model (SM) Higgs and lepton doublets and additional heavy right-handed neutrinos. These neutrinos participate to the renormalization group (RG) running of the dimensionless SM couplings, affecting their high-energy behavior. The Higgs quartic coupling is dragged towards negative values, thus altering the stability of the EW vacuum. In the usual type-I seesaw model, this effect is too small to be a threat since, in order to comply with low-energy neutrino data, one is forced to consider either too small Yukawa couplings or too heavy right-handed neutrinos. In this paper we explore this general idea in the context of low-scale seesaw models. These models are characterized by sizable Yukawa couplings and right-handed neutrinos with mass of the order of the EW scale, thus maximizing their impact on the RG flow. As a general result, we find that Yukawa couplings such that ${\rm Tr}(Y_{\nu}^{\dag}Y_{\nu}) \gtrsim 0.4$ are excluded. We discuss the impact of this bound on several observables, with a special focus on the lepton flavor violating process $\mu\to e\gamma$ and the neutrino-less double beta decay.
|
1705.05385
|
Joshua Eby
|
Joshua Eby, Michael Ma, Peter Suranyi, and L.C.R. Wijewardhana
|
Decay of Ultralight Axion Condensates
|
24 pages, 2 figures. v2: Added brief discussion of angular momentum;
extended Appendix A; typos corrected
|
J. High Energ. Phys. (2018) 2018: 66
|
10.1007/JHEP01(2018)066
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Axion particles can form macroscopic condensates, whose size can be galactic
in scale for models with very small axion masses $m\sim10^{-22}$ eV, and which
are sometimes referred to under the name of Fuzzy Dark Matter. Many analyses of
these condensates are done in the non-interacting limit, due to the weakness of
the self-interaction coupling of axions. We investigate here how certain
results change upon inclusion of these interactions, finding a decreased
maximum mass and a modified mass-radius relationship. Further, these
condensates are, in general, unstable to decay through number-changing
interactions. We analyze the stability of galaxy-sized condensates of
axion-like particles, and sketch the parameter space of stable configurations
as a function of a binding energy parameter. We find a strong lower bound on
the size of Fuzzy Dark Matter condensates which are stable to decay, with
lifetimes longer than the age of the universe.
|
[
{
"created": "Mon, 15 May 2017 18:00:05 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Feb 2018 11:53:51 GMT",
"version": "v2"
}
] |
2018-02-21
|
[
[
"Eby",
"Joshua",
""
],
[
"Ma",
"Michael",
""
],
[
"Suranyi",
"Peter",
""
],
[
"Wijewardhana",
"L. C. R.",
""
]
] |
Axion particles can form macroscopic condensates, whose size can be galactic in scale for models with very small axion masses $m\sim10^{-22}$ eV, and which are sometimes referred to under the name of Fuzzy Dark Matter. Many analyses of these condensates are done in the non-interacting limit, due to the weakness of the self-interaction coupling of axions. We investigate here how certain results change upon inclusion of these interactions, finding a decreased maximum mass and a modified mass-radius relationship. Further, these condensates are, in general, unstable to decay through number-changing interactions. We analyze the stability of galaxy-sized condensates of axion-like particles, and sketch the parameter space of stable configurations as a function of a binding energy parameter. We find a strong lower bound on the size of Fuzzy Dark Matter condensates which are stable to decay, with lifetimes longer than the age of the universe.
|
1907.08942
|
Antoni Szczurek
|
Antoni Szczurek and Piotr Lebiedowicz
|
Searching for odderon in exclusive reactions: $p p \to p p p {\bar p}$,
$p p \to p p \phi \phi$ and $p p \to p p \phi$
|
7 pages, 7 figures, a talk presented by A. Szczurek at DIS2019
workshop, 8-12 April 2019, Torino, Italy
| null | null | null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
There seem to be recently an evidence for $C =$ -1 exchanges in $p p$ and $p
\bar p$ elastic scattering at high energies. The analysis there is difficult as
the two processes were not measured at the same (large) energies. Here we
discuss three different exclusive processes given in the title as a possible
source of information for odderon exchange. A sketch of the formalism is
presented for each of the reactions. We consider low energy processes measured
in the past by the WA102 collaboration and try to make predictions for the LHC.
We discuss possible evidences at the low energies and try to make suggestions
for the LHC.
|
[
{
"created": "Sun, 21 Jul 2019 09:33:12 GMT",
"version": "v1"
}
] |
2019-07-23
|
[
[
"Szczurek",
"Antoni",
""
],
[
"Lebiedowicz",
"Piotr",
""
]
] |
There seem to be recently an evidence for $C =$ -1 exchanges in $p p$ and $p \bar p$ elastic scattering at high energies. The analysis there is difficult as the two processes were not measured at the same (large) energies. Here we discuss three different exclusive processes given in the title as a possible source of information for odderon exchange. A sketch of the formalism is presented for each of the reactions. We consider low energy processes measured in the past by the WA102 collaboration and try to make predictions for the LHC. We discuss possible evidences at the low energies and try to make suggestions for the LHC.
|
0904.1670
|
T. Lappi
|
T. Lappi
|
Initial conditions of heavy ion collisions and high energy factorization
|
15 pages, 5 figures, uses appolb.cls. Talk at the XV Cracow Epiphany
Conference, January 2009. V2: typo corrections. To be published in Acta Phys.
Polon. B
|
Acta Phys.Polon.B40:1997-2012,2009
| null |
IPhT-t09/062
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The Color Glass Condensate is an effective theory description for the small
momentum fraction x degrees of freedom in a high energy hadron or nucleus,
which can be understood in terms of strong classical gluon fields. We discuss
the resulting picture of the initial conditions in a relativistic heavy ion
collision. We describe recent work to show that the leading logarithms of the
collision energy can be factorized into the renormalization group evolution of
the small x wavefunction. We then describe how this framework can be used to
understand the long range rapidity correlations observed by the RHIC
experiments.
|
[
{
"created": "Fri, 10 Apr 2009 09:58:53 GMT",
"version": "v1"
},
{
"created": "Wed, 20 May 2009 09:19:16 GMT",
"version": "v2"
}
] |
2009-10-02
|
[
[
"Lappi",
"T.",
""
]
] |
The Color Glass Condensate is an effective theory description for the small momentum fraction x degrees of freedom in a high energy hadron or nucleus, which can be understood in terms of strong classical gluon fields. We discuss the resulting picture of the initial conditions in a relativistic heavy ion collision. We describe recent work to show that the leading logarithms of the collision energy can be factorized into the renormalization group evolution of the small x wavefunction. We then describe how this framework can be used to understand the long range rapidity correlations observed by the RHIC experiments.
|
2203.03977
|
Kai Murai
|
Tomohiro Fujita, Kai Murai, Ryo Namba
|
Universality of linear perturbations in SU($N$)-natural inflation
|
14 pages, 1 figure
|
Phys. Rev. D 105, 103518 (2022)
|
10.1103/PhysRevD.105.103518
|
RIKEN-iTHEMS-Report-22
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We prove the universality of predictions for linear perturbations from the
entire class of models of inflation driven by a pseudo-scalar field coupled to
an SU($N$) gauge boson, where SU($2$) subgroups in the SU($N$) crossed with the
background spatial SO($3$) spontaneously break into a single SO($3$). The
effect of which SU($2$) subgroup in SU($N$) acquires a VEV through spontaneous
symmetry breaking can be quantified by a single parameter $\lambda$, which
always appears in combination with the gauge coupling constant $g$. In the
linear perturbations, as well as the background system, the same dynamics and
predictions as in the chromo-natural inflation hold for its SU($N$) extension
by replacing $g \to g\lambda$. The latter models thereby draw the same
prediction curve on the $n_s$-$r$ plane as the former at the tree level as long
as $g \lambda$ stays constant during inflation. We briefly discuss possible
transitions from one value of $\lambda$ to another during inflation and the
observational prospects.
|
[
{
"created": "Tue, 8 Mar 2022 10:05:46 GMT",
"version": "v1"
},
{
"created": "Tue, 17 May 2022 07:32:54 GMT",
"version": "v2"
}
] |
2022-05-18
|
[
[
"Fujita",
"Tomohiro",
""
],
[
"Murai",
"Kai",
""
],
[
"Namba",
"Ryo",
""
]
] |
We prove the universality of predictions for linear perturbations from the entire class of models of inflation driven by a pseudo-scalar field coupled to an SU($N$) gauge boson, where SU($2$) subgroups in the SU($N$) crossed with the background spatial SO($3$) spontaneously break into a single SO($3$). The effect of which SU($2$) subgroup in SU($N$) acquires a VEV through spontaneous symmetry breaking can be quantified by a single parameter $\lambda$, which always appears in combination with the gauge coupling constant $g$. In the linear perturbations, as well as the background system, the same dynamics and predictions as in the chromo-natural inflation hold for its SU($N$) extension by replacing $g \to g\lambda$. The latter models thereby draw the same prediction curve on the $n_s$-$r$ plane as the former at the tree level as long as $g \lambda$ stays constant during inflation. We briefly discuss possible transitions from one value of $\lambda$ to another during inflation and the observational prospects.
|
hep-ph/9702363
| null |
X. Song, J. S. McCarthy and H. J. Weber
|
Nucleon spin-flavor structure in SU(3) breaking chiral quark model
|
18 pages, Latex, 4 tables. Phys. Rev. D (in press, submitted/revised
in June/Nov 1996)
|
Phys.Rev.D55:2624-2629,1997
|
10.1103/PhysRevD.55.2624
|
INPP-UVa-96-03 January 1996
|
hep-ph
| null |
The SU(3) symmetric chiral quark model, which describes interactions between
quarks, gluons and the Goldstone bosons, explains reasonably well many aspects
of the flavor and spin structure of the proton, except for the values of
$f_3/f_8$ and $\Delta_3/\Delta_8$. Introducing the SU(3)-breaking effect
suggested by the mass difference between the strange and nonstrange quarks, we
find that this discrepancy can be removed and better overall agreement
obtained.
|
[
{
"created": "Tue, 18 Feb 1997 22:01:34 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Song",
"X.",
""
],
[
"McCarthy",
"J. S.",
""
],
[
"Weber",
"H. J.",
""
]
] |
The SU(3) symmetric chiral quark model, which describes interactions between quarks, gluons and the Goldstone bosons, explains reasonably well many aspects of the flavor and spin structure of the proton, except for the values of $f_3/f_8$ and $\Delta_3/\Delta_8$. Introducing the SU(3)-breaking effect suggested by the mass difference between the strange and nonstrange quarks, we find that this discrepancy can be removed and better overall agreement obtained.
|
hep-ph/0007028
|
Lianshou Liu
|
FENG Shengqin, LIU Feng and LIU Lianshou
|
Thermal Freeze-out and Longitudinally Non-uniform Collective Expansion
Flow in Relativistic Heavy Ion Collisions
|
12 pages, 8 figures
| null | null |
HZPP0005
|
hep-ph
| null |
The non-uniform longitudinal flow model (NUFM) propsed recently is extended
to include also transverse flow. The resulting longitudinally non-uniform
collective expansion model (NUCEM) is applied to the calculation of rapidity
distribution of kaons, lambdas and protons in relativistic heavy ion collisions
at CERN-SPS energies. The model results are compared with the 200 A GeV/$c$ S-S
and 158 A GeV/$c$ Pb-Pb collision data. The central dips observed in
experiments are reproduced in a natural way.
|
[
{
"created": "Tue, 4 Jul 2000 14:02:06 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Shengqin",
"FENG",
""
],
[
"Feng",
"LIU",
""
],
[
"Lianshou",
"LIU",
""
]
] |
The non-uniform longitudinal flow model (NUFM) propsed recently is extended to include also transverse flow. The resulting longitudinally non-uniform collective expansion model (NUCEM) is applied to the calculation of rapidity distribution of kaons, lambdas and protons in relativistic heavy ion collisions at CERN-SPS energies. The model results are compared with the 200 A GeV/$c$ S-S and 158 A GeV/$c$ Pb-Pb collision data. The central dips observed in experiments are reproduced in a natural way.
|
1008.4325
|
Roman Pasechnik
|
Roman Pasechnik, Antoni Szczurek, and Oleg Teryaev
|
Polarisation effects in the central exclusive $\chi_c$ production and
the $J/\psi$ angular distributions
|
20 pages, 8 figures, discrepancies with Durham group results
clarified, numerics corrected, overall presentation and conclusions
significantly improved
|
Phys.Rev.D83:074017,2011
|
10.1103/PhysRevD.83.074017
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss exclusive elastic double diffractive axial-vector $\chi_c(1^+)$
and tensor $\chi_c(2^+)$ mesons production for different meson polarisations in
proton-(anti)proton collisions at the Tevatron energy. The amplitude for the
process is derived within the $k_t$-factorisation approach using unintegrated
gluon distributions (UGDFs). Differential cross sections for different $\chi_c$
polarisations are calculated. Angular distributions of $J/\psi$ meson from the
radiative $\chi_c(1^+,2^+)$ decays are derived. Prospects for experimental
selection of different spin states of $\chi_c$ mesons are discussed.
|
[
{
"created": "Wed, 25 Aug 2010 18:00:27 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Oct 2010 21:21:45 GMT",
"version": "v2"
}
] |
2011-04-28
|
[
[
"Pasechnik",
"Roman",
""
],
[
"Szczurek",
"Antoni",
""
],
[
"Teryaev",
"Oleg",
""
]
] |
We discuss exclusive elastic double diffractive axial-vector $\chi_c(1^+)$ and tensor $\chi_c(2^+)$ mesons production for different meson polarisations in proton-(anti)proton collisions at the Tevatron energy. The amplitude for the process is derived within the $k_t$-factorisation approach using unintegrated gluon distributions (UGDFs). Differential cross sections for different $\chi_c$ polarisations are calculated. Angular distributions of $J/\psi$ meson from the radiative $\chi_c(1^+,2^+)$ decays are derived. Prospects for experimental selection of different spin states of $\chi_c$ mesons are discussed.
|
2012.09865
|
Nirmal Raj
|
David McKeen, Maxim Pospelov, Nirmal Raj
|
Cosmological and astrophysical probes of dark baryons
|
10 pages + refs revtex4, 4 figures
|
Phys. Rev. D 103, 115002 (2021)
|
10.1103/PhysRevD.103.115002
| null |
hep-ph astro-ph.CO astro-ph.HE hep-ex
|
http://creativecommons.org/licenses/by/4.0/
|
We examine the cosmological and astrophysical signatures of a "dark baryon,"
a neutral fermion that mixes with the neutron. As the mixing is through a
higher-dimensional operator at the quark level, production of the dark baryon
at high energies is enhanced so that its abundance in the early universe may be
significant. Treating its initial abundance as a free parameter, we derive new,
powerful limits on the properties of the dark baryon. Primordial
nucleosynthesis and the cosmic microwave background provide strong constraints
due to the inter-conversion of neutrons to dark baryons through their induced
transition dipole, and due to late decays of the dark baryon. Additionally,
neutrons in a neutron star could decay slowly to dark baryons, providing a
novel source of heat that is constrained by measurements of pulsar
temperatures. Taking all the constraints into account, we identify parameter
space where the dark baryon can be a viable dark matter candidate and discuss
promising avenues for probing it.
|
[
{
"created": "Thu, 17 Dec 2020 19:00:00 GMT",
"version": "v1"
}
] |
2021-06-09
|
[
[
"McKeen",
"David",
""
],
[
"Pospelov",
"Maxim",
""
],
[
"Raj",
"Nirmal",
""
]
] |
We examine the cosmological and astrophysical signatures of a "dark baryon," a neutral fermion that mixes with the neutron. As the mixing is through a higher-dimensional operator at the quark level, production of the dark baryon at high energies is enhanced so that its abundance in the early universe may be significant. Treating its initial abundance as a free parameter, we derive new, powerful limits on the properties of the dark baryon. Primordial nucleosynthesis and the cosmic microwave background provide strong constraints due to the inter-conversion of neutrons to dark baryons through their induced transition dipole, and due to late decays of the dark baryon. Additionally, neutrons in a neutron star could decay slowly to dark baryons, providing a novel source of heat that is constrained by measurements of pulsar temperatures. Taking all the constraints into account, we identify parameter space where the dark baryon can be a viable dark matter candidate and discuss promising avenues for probing it.
|
1410.7298
|
Paul Mansfield
|
Paul Mansfield
|
The Fermion Content of the Standard Model
|
3 pages
| null | null |
DCPT-14/51
|
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We describe a simple model that automatically generates the sum over gauge
group representations and chiralities of a single generation of fermions in the
Standard Model, augmented by a sterile neutrino. The model is a modification of
the world-line approach to chiral fermions.
|
[
{
"created": "Mon, 27 Oct 2014 16:30:12 GMT",
"version": "v1"
}
] |
2014-10-28
|
[
[
"Mansfield",
"Paul",
""
]
] |
We describe a simple model that automatically generates the sum over gauge group representations and chiralities of a single generation of fermions in the Standard Model, augmented by a sterile neutrino. The model is a modification of the world-line approach to chiral fermions.
|
2110.07219
|
Yasaman Farzan
|
Yasaman Farzan
|
A dark matter solution for the XENON1T electron excess and the galactic
center 511 keV line
|
15 page, Presented at 16th Marcel Grossmann meeting (MG16)
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The excess of the 511 keV line from the Milky Way galactic bulge, confirmed
by the INTEGRAL detector, is a longstanding mystery. The morphology of the line
appears to be proportional to the square of the dark matter density, hinting
towards a dark matter origin. On the other hand, in 2020, XENON1T has reported
an excess of electrons with a recoil energy of $2-4$ keV. We present a model
based on a dark matter of a few MeV mass that decays into a pair of
pico-charged particles with a lifetime much larger than the age of the
Universe. The magnetic field of the galaxy accumulates these relativistic
pico-charged particles whose scattering on the electrons can explain the signal
reported by XENON1T. The annihilation of the pico-charged particles in the
galactic bulge leads to $e^-e^+$ production and therefore to an excess of the
511 keV line. We review the present observational bounds and the strategies to
test the model.
|
[
{
"created": "Thu, 14 Oct 2021 08:34:34 GMT",
"version": "v1"
}
] |
2021-10-15
|
[
[
"Farzan",
"Yasaman",
""
]
] |
The excess of the 511 keV line from the Milky Way galactic bulge, confirmed by the INTEGRAL detector, is a longstanding mystery. The morphology of the line appears to be proportional to the square of the dark matter density, hinting towards a dark matter origin. On the other hand, in 2020, XENON1T has reported an excess of electrons with a recoil energy of $2-4$ keV. We present a model based on a dark matter of a few MeV mass that decays into a pair of pico-charged particles with a lifetime much larger than the age of the Universe. The magnetic field of the galaxy accumulates these relativistic pico-charged particles whose scattering on the electrons can explain the signal reported by XENON1T. The annihilation of the pico-charged particles in the galactic bulge leads to $e^-e^+$ production and therefore to an excess of the 511 keV line. We review the present observational bounds and the strategies to test the model.
|
1707.09980
|
Reuven Balkin
|
Reuven Balkin, Gilad Perez, Andreas Weiler
|
Little composite dark matter
|
27 pages + appendices and references, 7 figures
|
Eur.Phys.J. C78 (2018) no.2, 104
|
10.1140/epjc/s10052-018-5552-3
|
TUM-HEP-1092-17
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We examine the dark matter phenomenology of a composite electroweak singlet
state. This singlet belongs to the Goldstone sector of a well-motivated
extension of the Littlest Higgs with $T$-parity. A viable parameter space,
consistent with the observed dark matter relic abundance as well as with the
various collider, electroweak precision and dark matter direct detection
experimental constraints is found for this scenario. $T$-parity implies a rich
LHC phenomenology, which forms an interesting interplay between conventional
natural SUSY type of signals involving third generation quarks and missing
energy, from stop-like particle production and decay, and composite Higgs type
of signals involving third generation quarks associated with Higgs and
electroweak gauge boson, from vector-like top-partners production and decay.
The composite features of the dark matter phenomenology allows the composite
singlet the produce the correct relic abundance while interacting weakly with
the Higgs via the usual Higgs portal coupling $\lambda_{\text{DM}} \sim
O(1\%)$, thus evading direct detection.
|
[
{
"created": "Mon, 31 Jul 2017 17:59:47 GMT",
"version": "v1"
}
] |
2018-02-13
|
[
[
"Balkin",
"Reuven",
""
],
[
"Perez",
"Gilad",
""
],
[
"Weiler",
"Andreas",
""
]
] |
We examine the dark matter phenomenology of a composite electroweak singlet state. This singlet belongs to the Goldstone sector of a well-motivated extension of the Littlest Higgs with $T$-parity. A viable parameter space, consistent with the observed dark matter relic abundance as well as with the various collider, electroweak precision and dark matter direct detection experimental constraints is found for this scenario. $T$-parity implies a rich LHC phenomenology, which forms an interesting interplay between conventional natural SUSY type of signals involving third generation quarks and missing energy, from stop-like particle production and decay, and composite Higgs type of signals involving third generation quarks associated with Higgs and electroweak gauge boson, from vector-like top-partners production and decay. The composite features of the dark matter phenomenology allows the composite singlet the produce the correct relic abundance while interacting weakly with the Higgs via the usual Higgs portal coupling $\lambda_{\text{DM}} \sim O(1\%)$, thus evading direct detection.
|
1807.03690
|
Osvaldo Civitarese
|
M.Mosquera, O. Civitarese
|
Decoherence-effects in the neutrino-mixing mechanism: active and sterile
neutrinos in the three flavor scheme
|
8 pages, 5 figures
| null | null | null |
hep-ph astro-ph.HE
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this work we analyze the effects of quantum decoherence upon the
precession of the neutrino polarization vector in a supernovae-like
environment. In order to perform the study we have determined the
time-dependence of the polarization vector by solving the equation of motion
for different neutrino-mixing schemes. The results of the calculations show
that the onset of decoherence depends strongly on the parameters of the adopted
mixing scheme. As examples we have considered : a) the mixing between active
neutrinos and b) the mixing between active end sterile neutrinos.
|
[
{
"created": "Tue, 10 Jul 2018 14:57:39 GMT",
"version": "v1"
}
] |
2018-07-11
|
[
[
"Mosquera",
"M.",
""
],
[
"Civitarese",
"O.",
""
]
] |
In this work we analyze the effects of quantum decoherence upon the precession of the neutrino polarization vector in a supernovae-like environment. In order to perform the study we have determined the time-dependence of the polarization vector by solving the equation of motion for different neutrino-mixing schemes. The results of the calculations show that the onset of decoherence depends strongly on the parameters of the adopted mixing scheme. As examples we have considered : a) the mixing between active neutrinos and b) the mixing between active end sterile neutrinos.
|
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