id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1906.11800 | Francesco Giovanni Celiberto | Andr\`ee Dafne Bolognino, Francesco Giovanni Celiberto, Dmitry Yu.
Ivanov, Mohammed M.A. Mohammed, Alessandro Papa | High-energy effects in forward inclusive dijet and hadron-jet production | 6 pages, 2 figures; contribution to the proceedings of the XXVII
International Workshop on Deep Inelastic Scattering and Related Subjects
(DIS2019), Torino, Italy, 8-12 April, 2019; to appear on Proceedings of
Science | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Pursuing the goal to single out the validity region of the high-energy
resummation, better known as BFKL approach, and to possibly disentangle BFKL
effects from the ones coming from a DGLAP-inspired, fixed-order description,
new predictions for the forward inclusive hadron-jet production, tailored on
the CMS and CASTOR acceptances, are given.
| [
{
"created": "Thu, 27 Jun 2019 17:14:53 GMT",
"version": "v1"
}
] | 2019-06-28 | [
[
"Bolognino",
"Andrèe Dafne",
""
],
[
"Celiberto",
"Francesco Giovanni",
""
],
[
"Ivanov",
"Dmitry Yu.",
""
],
[
"Mohammed",
"Mohammed M. A.",
""
],
[
"Papa",
"Alessandro",
""
]
] | Pursuing the goal to single out the validity region of the high-energy resummation, better known as BFKL approach, and to possibly disentangle BFKL effects from the ones coming from a DGLAP-inspired, fixed-order description, new predictions for the forward inclusive hadron-jet production, tailored on the CMS and CASTOR acceptances, are given. |
2402.18870 | Vinod Chandra | Vinod Chandra and Santosh K. Das | B-mesons as essential probes of hot QCD matter | 17 Pages, 3 Figures, Invited Review for The European Physical Journal
Special Topics | Eur. Phys. J. Spec. Top. (2024) | 10.1140/epjs/s11734-024-01123-4 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | This article elucidates the pivotal role of b-mesons and bottomonium states
in exploring the existence and properties of hot QCD matter (commonly known as
quark-gluon-plasma (QGP) produced within the crucible heavy-ion collision
experiments). Owing to the complex and confounding nature of strong interaction
force the direct detection of probing the hot QCD matter is not feasible. In
light of this, investigating the dynamics of b-quarks and anti-quarks within
the hot QCD medium emerges as an invaluable indirect probe. The impact of
b-quarks and the mesons spans a spectrum of interesting domains regarding the
physics of QCD at finite temperature, encompassing the QCD phase transition,
color screening, quarkonia dissociation, heavy quark energy loss and collective
flow, anisotropic aspects, and strongly coupled nature of hot QCD medium. These
aspects underscore the indispensable nature of B-mesons in the quest to create
and explore the complex nature of strong interaction force through the QGP/hot
QCD matter. In this context, we mainly focus on works related to transport
studies of b-mesons in hot QCD medium, lattice QCD, and effective field theory
studies on bottomonium states, and finally, open quantum system frameworks to
quarkonia to explore the properties of hot QCD medium in relativistic heavy-ion
collision experiments.
| [
{
"created": "Thu, 29 Feb 2024 05:39:33 GMT",
"version": "v1"
}
] | 2024-03-01 | [
[
"Chandra",
"Vinod",
""
],
[
"Das",
"Santosh K.",
""
]
] | This article elucidates the pivotal role of b-mesons and bottomonium states in exploring the existence and properties of hot QCD matter (commonly known as quark-gluon-plasma (QGP) produced within the crucible heavy-ion collision experiments). Owing to the complex and confounding nature of strong interaction force the direct detection of probing the hot QCD matter is not feasible. In light of this, investigating the dynamics of b-quarks and anti-quarks within the hot QCD medium emerges as an invaluable indirect probe. The impact of b-quarks and the mesons spans a spectrum of interesting domains regarding the physics of QCD at finite temperature, encompassing the QCD phase transition, color screening, quarkonia dissociation, heavy quark energy loss and collective flow, anisotropic aspects, and strongly coupled nature of hot QCD medium. These aspects underscore the indispensable nature of B-mesons in the quest to create and explore the complex nature of strong interaction force through the QGP/hot QCD matter. In this context, we mainly focus on works related to transport studies of b-mesons in hot QCD medium, lattice QCD, and effective field theory studies on bottomonium states, and finally, open quantum system frameworks to quarkonia to explore the properties of hot QCD medium in relativistic heavy-ion collision experiments. |
2309.07840 | Vishvas Pandey | V. Pandey | Recent Progress in Low Energy Neutrino Scattering Physics and Its
Implications for the Standard and Beyond the Standard Model Physics | Invited review article for the Progress in Particle and Nuclear
Physics. Published version. 58 pages, 11 figures, 5 tables | Prog. Part. Nucl. Phys. 134, 104078 (2024) | 10.1016/j.ppnp.2023.104078 | FERMILAB-PUB-23-245-ND | hep-ph hep-ex nucl-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | Neutrinos continue to provide a testing ground for the structure of the
standard model of particle physics as well as hints towards the physics beyond
the standard model. Neutrinos of energies spanning over several orders of
magnitude, originating in many terrestrial and astrophysical processes, have
been detected via various decay and interaction mechanisms. At MeV scales,
there has been one elusive process, until a few years ago, known as coherent
elastic neutrino-nucleus scattering (CEvNS) that was theoretically predicted
over five decades ago but was never observed experimentally. The recent
experimental observation of the CEvNS process by the COHERENT collaboration at
a stopped pion neutrino source has inspired physicists across many subfields.
This has vital implications for nuclear physics, high-energy physics,
astrophysics, and beyond. CEvNS, being a low-energy process, provides a natural
window to study light, weakly-coupled, new physics in the neutrino sector.
In this review, we intend to provide the current status of low energy
neutrino scattering physics and its implications for the standard and beyond
the standard model physics. We discuss the general formalism of calculating the
tree-level CEvNS cross section and present estimated theoretical uncertainties
on the CEvNS cross section stemming from different sources. We also discuss the
inelastic scattering of tens of MeV neutrinos that have implications for
supernova detection in future neutrino experiments. We discuss how the CEvNS
experiments can be used as a testing ground for the Standard Model (SM) weak
physics as well as in searching for the Beyond the Standard Model (BSM) physics
signals. Any deviation from the SM predicted event rate either with a change in
the total event rate or with a change in the shape of the recoil spectrum,
could indicate new contributions to the interaction cross-section.
| [
{
"created": "Thu, 14 Sep 2023 16:36:36 GMT",
"version": "v1"
}
] | 2023-12-19 | [
[
"Pandey",
"V.",
""
]
] | Neutrinos continue to provide a testing ground for the structure of the standard model of particle physics as well as hints towards the physics beyond the standard model. Neutrinos of energies spanning over several orders of magnitude, originating in many terrestrial and astrophysical processes, have been detected via various decay and interaction mechanisms. At MeV scales, there has been one elusive process, until a few years ago, known as coherent elastic neutrino-nucleus scattering (CEvNS) that was theoretically predicted over five decades ago but was never observed experimentally. The recent experimental observation of the CEvNS process by the COHERENT collaboration at a stopped pion neutrino source has inspired physicists across many subfields. This has vital implications for nuclear physics, high-energy physics, astrophysics, and beyond. CEvNS, being a low-energy process, provides a natural window to study light, weakly-coupled, new physics in the neutrino sector. In this review, we intend to provide the current status of low energy neutrino scattering physics and its implications for the standard and beyond the standard model physics. We discuss the general formalism of calculating the tree-level CEvNS cross section and present estimated theoretical uncertainties on the CEvNS cross section stemming from different sources. We also discuss the inelastic scattering of tens of MeV neutrinos that have implications for supernova detection in future neutrino experiments. We discuss how the CEvNS experiments can be used as a testing ground for the Standard Model (SM) weak physics as well as in searching for the Beyond the Standard Model (BSM) physics signals. Any deviation from the SM predicted event rate either with a change in the total event rate or with a change in the shape of the recoil spectrum, could indicate new contributions to the interaction cross-section. |
0807.3775 | Hitoshi Murayama | Hitoshi Murayama | Looking up at seesaw and GUT scales from TeV | Proceedings of "Grand Unified Theories: Current Status and Future
Prospects: An International Workshop", Kusatsu, Shiga, Japan, 17-19 December
2007 | AIP Conference Proceedings, High Energy Physics, Vol. 1015, 2008 | 10.1063/1.2939052 | IPMU08-0018 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk, I discuss how we may approach physics at the seesaw- and
GUT-scales using data from the TeV scale. Even though we cannot hope to
directly reach these energy scales using particle accelerators, we may get
convinced of grand unification and seesaw mechanism based on experimental data
if Nature is kind to us. In addition, we may find compelling reason to believe
in leptogenesis based on experimental data. This cannot be achieved by a single
experiment, but rather a collection of them, based on LHC, ILC, neutrino
oscillation, neutrinoless double beta decay, direct dark matter detection, CMB
power spectrum and its tensor mode.
| [
{
"created": "Thu, 24 Jul 2008 01:27:45 GMT",
"version": "v1"
}
] | 2009-11-13 | [
[
"Murayama",
"Hitoshi",
""
]
] | In this talk, I discuss how we may approach physics at the seesaw- and GUT-scales using data from the TeV scale. Even though we cannot hope to directly reach these energy scales using particle accelerators, we may get convinced of grand unification and seesaw mechanism based on experimental data if Nature is kind to us. In addition, we may find compelling reason to believe in leptogenesis based on experimental data. This cannot be achieved by a single experiment, but rather a collection of them, based on LHC, ILC, neutrino oscillation, neutrinoless double beta decay, direct dark matter detection, CMB power spectrum and its tensor mode. |
hep-ph/0602027 | Shrihari Gopalakrishna | Shrihari Gopalakrishna, Andre de Gouvea, Werner Porod | Right-handed Sneutrinos as Nonthermal Dark Matter | 17 pages v.2: References added | JCAP 0605 (2006) 005 | 10.1088/1475-7516/2006/05/005 | IFIC/06-01, NUHEP-TH/06-01 | hep-ph astro-ph | null | When the minimal supersymmetric standard model is augmented by three
right-handed neutrino superfields, one generically predicts that the neutrinos
acquire Majorana masses. We postulate that all supersymmetry (SUSY) breaking
masses as well as the Majorana masses of the right-handed neutrinos are around
the electroweak scale and, motivated by the smallness of neutrino masses,
assume that the lightest supersymmetric particle (LSP) is an almost-pure
right-handed sneutrino. We discuss the conditions under which this LSP is a
successful dark matter candidate. In general, such an LSP has to be nonthermal
in order not to overclose the universe, and we find the conditions under which
this is indeed the case by comparing the Hubble expansion rate with the rates
of the relevant thermalizing processes, including self-annihilation and
co-annihilation with other SUSY and standard model particles.
| [
{
"created": "Thu, 2 Feb 2006 20:53:04 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Feb 2006 00:45:52 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Gopalakrishna",
"Shrihari",
""
],
[
"de Gouvea",
"Andre",
""
],
[
"Porod",
"Werner",
""
]
] | When the minimal supersymmetric standard model is augmented by three right-handed neutrino superfields, one generically predicts that the neutrinos acquire Majorana masses. We postulate that all supersymmetry (SUSY) breaking masses as well as the Majorana masses of the right-handed neutrinos are around the electroweak scale and, motivated by the smallness of neutrino masses, assume that the lightest supersymmetric particle (LSP) is an almost-pure right-handed sneutrino. We discuss the conditions under which this LSP is a successful dark matter candidate. In general, such an LSP has to be nonthermal in order not to overclose the universe, and we find the conditions under which this is indeed the case by comparing the Hubble expansion rate with the rates of the relevant thermalizing processes, including self-annihilation and co-annihilation with other SUSY and standard model particles. |
1512.08221 | Hyung Do Kim | Dongjin Chway, Radovan Dermisek, Tae Hyun Jung, Hyung Do Kim | Glue to light signal of a new particle | 5 pages, 8 figures, resummation of gluon exchanges near the threshold
and discussion added | Phys. Rev. Lett. 117, 061801 (2016) | 10.1103/PhysRevLett.117.061801 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Any new particle charged under $SU(3)_C$ and carrying electric charge will
leave an imprint in the di-photon invariant mass spectrum as it can mediate $gg
\to \gamma \gamma$ process through loops. The combination of properties of loop
functions, threshold resummation and gluon pdfs can result in a peak-like
feature in the di-photon invariant mass around twice the mass of a given
particle even if the particle is short-lived and thus it doesn't form a narrow
bound state. Using recent ATLAS analysis, we set upper limits on the combined
$SU(3)_C$ and electric charge of new particles and indicate future prospects.
We also discuss the possibility that the excess of events in the di-photon
invariant mass spectrum around 750 GeV originates from loops of a particle with
mass around 375 GeV.
| [
{
"created": "Sun, 27 Dec 2015 13:55:02 GMT",
"version": "v1"
},
{
"created": "Sun, 1 May 2016 14:28:27 GMT",
"version": "v2"
}
] | 2016-08-10 | [
[
"Chway",
"Dongjin",
""
],
[
"Dermisek",
"Radovan",
""
],
[
"Jung",
"Tae Hyun",
""
],
[
"Kim",
"Hyung Do",
""
]
] | Any new particle charged under $SU(3)_C$ and carrying electric charge will leave an imprint in the di-photon invariant mass spectrum as it can mediate $gg \to \gamma \gamma$ process through loops. The combination of properties of loop functions, threshold resummation and gluon pdfs can result in a peak-like feature in the di-photon invariant mass around twice the mass of a given particle even if the particle is short-lived and thus it doesn't form a narrow bound state. Using recent ATLAS analysis, we set upper limits on the combined $SU(3)_C$ and electric charge of new particles and indicate future prospects. We also discuss the possibility that the excess of events in the di-photon invariant mass spectrum around 750 GeV originates from loops of a particle with mass around 375 GeV. |
hep-ph/9908391 | Bogdan A. Dobrescu | Bogdan A. Dobrescu | Minimal Composite Higgs Model with Light Bosons | 33 pages, latex. Corrections in eqs. 3.21, 3.23, 4.1, 4.5-10. One
figure added | Phys.Rev. D63 (2001) 015004 | 10.1103/PhysRevD.63.015004 | FERMILAB-PUB-99-234-T | hep-ph | null | We analyze a composite Higgs model with the minimal content that allows a
light Standard-Model-like Higgs boson, potentially just above the current LEP
limit. The Higgs boson is a bound state made up of the top quark and a heavy
vector-like quark. The model predicts that only one other bound state may be
lighter than the electroweak scale, namely a CP-odd neutral scalar. Several
other composite scalars are expected to have masses in the TeV range. If the
Higgs decay into a pair of CP-odd scalars is kinematically open, then this
decay mode is dominant, with important implications for Higgs searches. The
lower bound on the CP-odd scalar mass is loose, in some cases as low as $\sim$
100 MeV, being set only by astrophysical constraints.
| [
{
"created": "Tue, 17 Aug 1999 22:54:33 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Sep 1999 21:08:34 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Dobrescu",
"Bogdan A.",
""
]
] | We analyze a composite Higgs model with the minimal content that allows a light Standard-Model-like Higgs boson, potentially just above the current LEP limit. The Higgs boson is a bound state made up of the top quark and a heavy vector-like quark. The model predicts that only one other bound state may be lighter than the electroweak scale, namely a CP-odd neutral scalar. Several other composite scalars are expected to have masses in the TeV range. If the Higgs decay into a pair of CP-odd scalars is kinematically open, then this decay mode is dominant, with important implications for Higgs searches. The lower bound on the CP-odd scalar mass is loose, in some cases as low as $\sim$ 100 MeV, being set only by astrophysical constraints. |
0911.3694 | Xiang Liu | Xiang Liu, Zhi-Gang Luo and Zhi-Feng Sun | X(3915) and X(4350) as new members in P-wave charmonium family | 4 pages, 2 figures, 2 tables. More references and discussions added,
typos corrected. Accepted for publication in Phys. Rev. Lett. | Phys.Rev.Lett.104:122001,2010 | 10.1103/PhysRevLett.104.122001 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The analysis of the mass spectrum and the calculation of the strong decay of
P-wave charmonium states strongly support to explain the newly observed X(3915)
and X(4350) as new members in P-wave charmonium family, i.e.,
$\chi_{c0}^\prime$ for X(3915) and $\chi_{c2}^{\prime\prime}$ for X(4350).
Under the P-wave charmonium assignment to X(3915) and X(4350), the $J^{PC}$
quantum numbers of X(3915) and X(4350) must be $0^{++}$ and $2^{++}$
respectively, which provide the important criterion to test P-wave charmonium
explanation for X(3915) and X(4350) proposed by this letter. The decay behavior
of the remaining two P-wave charmonium states with the second radial excitation
is predicted, and experimental search for them is suggested.
| [
{
"created": "Thu, 19 Nov 2009 13:52:52 GMT",
"version": "v1"
},
{
"created": "Sun, 3 Jan 2010 07:52:57 GMT",
"version": "v2"
},
{
"created": "Sat, 6 Mar 2010 08:27:02 GMT",
"version": "v3"
}
] | 2010-04-06 | [
[
"Liu",
"Xiang",
""
],
[
"Luo",
"Zhi-Gang",
""
],
[
"Sun",
"Zhi-Feng",
""
]
] | The analysis of the mass spectrum and the calculation of the strong decay of P-wave charmonium states strongly support to explain the newly observed X(3915) and X(4350) as new members in P-wave charmonium family, i.e., $\chi_{c0}^\prime$ for X(3915) and $\chi_{c2}^{\prime\prime}$ for X(4350). Under the P-wave charmonium assignment to X(3915) and X(4350), the $J^{PC}$ quantum numbers of X(3915) and X(4350) must be $0^{++}$ and $2^{++}$ respectively, which provide the important criterion to test P-wave charmonium explanation for X(3915) and X(4350) proposed by this letter. The decay behavior of the remaining two P-wave charmonium states with the second radial excitation is predicted, and experimental search for them is suggested. |
hep-ph/0008328 | Shinji Tsujikawa | Bruce A. Bassett (Portsmouth), Shinji Tsujikawa (Waseda) | Inflationary preheating and primordial black holes | 7 pages, 6 figures. Fig 6 is added to show the weak dependence of the
mass variance on the initial condition | Phys.Rev. D63 (2001) 123503 | 10.1103/PhysRevD.63.123503 | RCG-00/27, WUAP-00/22 | hep-ph astro-ph gr-qc hep-th | null | Preheating after inflation may over-produce primordial black holes (PBH's) in
many regions of parameter space. As an example we study two-field models with a
massless self-interacting inflaton, taking into account second order field and
metric backreaction effects as spatial averages. We find that a complex quilt
of parameter regions above the Gaussian PBH over-production threshold emerges
due to the enhancement of curvature perturbations on all scales. It should be
possible to constrain realistic models of inflation through PBH over-production
although many issues, such as rescattering and non-Gaussianity, remain unsolved
or unexplored.
| [
{
"created": "Thu, 31 Aug 2000 09:09:09 GMT",
"version": "v1"
},
{
"created": "Thu, 11 Jan 2001 04:28:30 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Bassett",
"Bruce A.",
"",
"Portsmouth"
],
[
"Tsujikawa",
"Shinji",
"",
"Waseda"
]
] | Preheating after inflation may over-produce primordial black holes (PBH's) in many regions of parameter space. As an example we study two-field models with a massless self-interacting inflaton, taking into account second order field and metric backreaction effects as spatial averages. We find that a complex quilt of parameter regions above the Gaussian PBH over-production threshold emerges due to the enhancement of curvature perturbations on all scales. It should be possible to constrain realistic models of inflation through PBH over-production although many issues, such as rescattering and non-Gaussianity, remain unsolved or unexplored. |
1708.02047 | Kimberley Keri Vos | Rebecca Klein, Thomas Mannel, Javier Virto and K. Keri Vos | CP Violation in Multibody $B$ Decays from QCD Factorization | 17 pages, 6 figures, added references | JHEP 10, 117 (2017) | 10.1007/JHEP10(2017)117 | SI-HEP-2017-15, QFET-2017-13, MIT-CTP-4926, NIOBE-2017-03,
TUM-1095/17 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We test a data-driven approach based on QCD factorization for charmless
three-body $B$-decays by confronting it to measurements of CP violation in $B^-
\to \pi^- \pi^+ \pi^-$. While some of the needed non-perturbative objects can
be directly extracted from data, some others can, so far, only be modelled.
Although this approach is currently model dependent, we comment on the
perspectives to reduce this model dependence. While our model naturally
accommodates the gross features of the Dalitz distribution, it cannot
quantitatively explain the details seen in the current experimental data on
local CP asymmetries. We comment on possible refinements of our simple model
and conclude by briefly discussing a possible extension of the model to large
invariant masses, where large local CP asymmetries have been measured.
| [
{
"created": "Mon, 7 Aug 2017 09:14:33 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Oct 2017 13:57:35 GMT",
"version": "v2"
}
] | 2017-10-23 | [
[
"Klein",
"Rebecca",
""
],
[
"Mannel",
"Thomas",
""
],
[
"Virto",
"Javier",
""
],
[
"Vos",
"K. Keri",
""
]
] | We test a data-driven approach based on QCD factorization for charmless three-body $B$-decays by confronting it to measurements of CP violation in $B^- \to \pi^- \pi^+ \pi^-$. While some of the needed non-perturbative objects can be directly extracted from data, some others can, so far, only be modelled. Although this approach is currently model dependent, we comment on the perspectives to reduce this model dependence. While our model naturally accommodates the gross features of the Dalitz distribution, it cannot quantitatively explain the details seen in the current experimental data on local CP asymmetries. We comment on possible refinements of our simple model and conclude by briefly discussing a possible extension of the model to large invariant masses, where large local CP asymmetries have been measured. |
hep-ph/0509312 | Leonard Gamberg | Leonard P. Gamberg and Gary R. Goldstein | Transversity Properties of Quarks and Hadrons in SIDIS and Drell-Yan | 4 pages, 8 figures. To appear in the proceedings of the XIII
International Workshop on Deep Inelastic Scattering (DIS 2005, Madison) | null | 10.1063/1.2122192 | null | hep-ph | null | We consider the leading twist $T$-odd contributions as the dominant source of
the azimuthal and transverse single spin asymmetries in SIDIS and dilepton
production in Drell-Yan Scattering. These asymmetries contain information on
the distribution of quark transverse spin in (un)polarized protons. In the
spectator framework we estimate these asymmetries at HERMES kinematics and at
$50\ {\rm GeV}$ for the proposed experiments at GSI, where an anti-proton beam
is ideal for studying the transversity properties of quarks due to the
dominance of {\em valence} quark effects.
| [
{
"created": "Tue, 27 Sep 2005 18:18:30 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Gamberg",
"Leonard P.",
""
],
[
"Goldstein",
"Gary R.",
""
]
] | We consider the leading twist $T$-odd contributions as the dominant source of the azimuthal and transverse single spin asymmetries in SIDIS and dilepton production in Drell-Yan Scattering. These asymmetries contain information on the distribution of quark transverse spin in (un)polarized protons. In the spectator framework we estimate these asymmetries at HERMES kinematics and at $50\ {\rm GeV}$ for the proposed experiments at GSI, where an anti-proton beam is ideal for studying the transversity properties of quarks due to the dominance of {\em valence} quark effects. |
2406.08143 | Cornelis J.G. Mommers | Cornelis J.G. Mommers, Marc Vanderhaeghen | Constraining the axial-vector X17 interpretation with ${}^{12}$C data | 1 figure | null | null | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | Recent findings of an unexpected, narrow resonance in the $e^+e^-$ decay
spectra of excited states of $^8$Be, $^4$He and $^{12}$C by the ATOMKI
collaboration have received considerable experimental and theoretical
attention, whereby a new, 17-MeV vector-like or axial-vector-like boson termed
X17 was conjectured as an explanation of the anomaly. Further analysis of all
existing constraints disfavors a vector X17 scenario. For a similar analysis of
the axial-vector scenario, a calculation of the reduced matrix element of a
spin-dipole operator between the excited nuclear state ${}^{12}$C(17.23) and
the carbon ground state is required. In the present work, we compute the
aforementioned reduced matrix element under the assumption that the state
${}^{12}$C(17.23) is well represented by the $2s_{1/2}1p^{-1}_{3/2}$
particle-hole shell-model excitation of the ground state, as supported by
experimental data. Within such a framework, our results indicate that, like the
vector scenario, the axial-vector interpretation of X17 shows strong tensions
with the other existing constraints on the nucleon coupling of a conjectured
X17.
| [
{
"created": "Wed, 12 Jun 2024 12:34:44 GMT",
"version": "v1"
}
] | 2024-06-13 | [
[
"Mommers",
"Cornelis J. G.",
""
],
[
"Vanderhaeghen",
"Marc",
""
]
] | Recent findings of an unexpected, narrow resonance in the $e^+e^-$ decay spectra of excited states of $^8$Be, $^4$He and $^{12}$C by the ATOMKI collaboration have received considerable experimental and theoretical attention, whereby a new, 17-MeV vector-like or axial-vector-like boson termed X17 was conjectured as an explanation of the anomaly. Further analysis of all existing constraints disfavors a vector X17 scenario. For a similar analysis of the axial-vector scenario, a calculation of the reduced matrix element of a spin-dipole operator between the excited nuclear state ${}^{12}$C(17.23) and the carbon ground state is required. In the present work, we compute the aforementioned reduced matrix element under the assumption that the state ${}^{12}$C(17.23) is well represented by the $2s_{1/2}1p^{-1}_{3/2}$ particle-hole shell-model excitation of the ground state, as supported by experimental data. Within such a framework, our results indicate that, like the vector scenario, the axial-vector interpretation of X17 shows strong tensions with the other existing constraints on the nucleon coupling of a conjectured X17. |
hep-ph/9809350 | null | Ignazio Scimemi | NLO corrections to Delta F=2 effective Hamiltonians and SUSY
contribution to FCNC | 4 pages. Talk given at International Euroconference on Quantum
Chromodynamics (QCD98), Montpellier, France, 2-8 july 1998. Submitted to
Nucl. Phys. B (Proc. Suppl.) | Nucl.Phys.Proc.Suppl.74:243-246,1999 | 10.1016/S0920-5632(99)00172-3 | null | hep-ph | null | The most general QCD-NLO Anomalous-Dimension Matrix of all four-fermion
dimension six Delta F=2 operators is presented. Two applications of this
Anomalous-Dimension Matrix to the study of SUSY contribution to K- Kbar mixing
are also discussed.
| [
{
"created": "Sat, 12 Sep 1998 13:31:06 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Scimemi",
"Ignazio",
""
]
] | The most general QCD-NLO Anomalous-Dimension Matrix of all four-fermion dimension six Delta F=2 operators is presented. Two applications of this Anomalous-Dimension Matrix to the study of SUSY contribution to K- Kbar mixing are also discussed. |
1402.3087 | Tai Li | Tai Li and Yu-Feng Zhou | Strongly first order phase transition in the singlet fermionic dark
matter model after LUX | 37 pages, 9 figures; v4: the version accepted by JHEP | null | 10.1007/JHEP07(2014)006 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate an extension of the standard model (SM) with a singlet
fermionic dark matter (DM) particle which interacts with the SM sector through
a real singlet scalar. The presence of a new scalar provides the possibility of
generating a strongly first order phase transition needed for electroweak
baryogenesis. Taking into account the latest Higgs search results at the LHC
and the upper limits from the DM direct detection experiments especially that
from the LUX experiment, and combining the constraints from the LEP experiment
and the electroweak precision test, we explore the parameter space of this
model which can lead to the strongly first order phase transition. Both the
tree- and loop-level barriers are included in the calculations. We find that
the allowed mass of the second Higgs particle is in the range $\sim
30-350\hbox{ GeV}$. The allowed mixing angle $\alpha$ between the SM-like Higgs
particle and the second Higgs particle is constrained to $\alpha \lesssim
28^{\circ}$. The DM particle mass is predicted to be in the range $\sim
15-350\hbox{ GeV}$. The future XENON1T experiment can rule out a significant
proportion of the parameter space of this model. The constraint can be relaxed
only when the mass of the SM-like Higgs particle is degenerate with that of the
second Higgs particle, or the mixing angle is small enough.
| [
{
"created": "Thu, 13 Feb 2014 11:02:35 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Feb 2014 14:06:15 GMT",
"version": "v2"
},
{
"created": "Mon, 23 Jun 2014 09:22:30 GMT",
"version": "v3"
},
{
"created": "Tue, 24 Jun 2014 11:46:54 GMT",
"version": "v4"
}
] | 2015-06-18 | [
[
"Li",
"Tai",
""
],
[
"Zhou",
"Yu-Feng",
""
]
] | We investigate an extension of the standard model (SM) with a singlet fermionic dark matter (DM) particle which interacts with the SM sector through a real singlet scalar. The presence of a new scalar provides the possibility of generating a strongly first order phase transition needed for electroweak baryogenesis. Taking into account the latest Higgs search results at the LHC and the upper limits from the DM direct detection experiments especially that from the LUX experiment, and combining the constraints from the LEP experiment and the electroweak precision test, we explore the parameter space of this model which can lead to the strongly first order phase transition. Both the tree- and loop-level barriers are included in the calculations. We find that the allowed mass of the second Higgs particle is in the range $\sim 30-350\hbox{ GeV}$. The allowed mixing angle $\alpha$ between the SM-like Higgs particle and the second Higgs particle is constrained to $\alpha \lesssim 28^{\circ}$. The DM particle mass is predicted to be in the range $\sim 15-350\hbox{ GeV}$. The future XENON1T experiment can rule out a significant proportion of the parameter space of this model. The constraint can be relaxed only when the mass of the SM-like Higgs particle is degenerate with that of the second Higgs particle, or the mixing angle is small enough. |
1108.0890 | Feng Feng | Juan Zhang, Hairong Dong, and Feng Feng | Exclusive decay of P-wave Bottomonium into double J/\psi | 16 pages, 2 figures, published version. arXiv admin note: text
overlap with arXiv:0912.5498 and arXiv:hep-ph/0611130v2 | null | 10.1103/PhysRevD.84.094031 | Phys. Rev. D 84, 094031 (2011) | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the order-v^2 relativistic correction of J/\psi, including
electromagnetic correction, to \chi_{bJ}-> J/\psi J/\psi, in the framework of
NRQCD factorization formula. The relativistic order-v^2 effect is found to
increase the lower-order prediction for the decay width by about 10%, while the
electromagnetism contribution is very small about 0.2% for \chi_{b0} and
\chi_{b2}. The total branching ratios are predicted to be of order 10^{-5} for
\chi_{b0,b2}-> J/\psi J/\psi, but 10^{-11} for \chi_{b1}-> J/\psi J/\psi, since
there is only electromagnetism contribution in this channel. We predict it is
possible to observe these reactions in LHC. Finally, we estimate the decay
width and branch ratio of \chi_{cJ}-> \omega\omega,\phi\phi) in the constituent
quark model by our formula at the leading-order of relativistic correction and
electromagnetic correction. The obtained branch ratio of \chi_{c0,2}-> \phi\phi
is in agreement with the experimental measurement in the order of magnitude.
| [
{
"created": "Wed, 3 Aug 2011 16:47:00 GMT",
"version": "v1"
},
{
"created": "Fri, 5 Aug 2011 16:52:46 GMT",
"version": "v2"
},
{
"created": "Mon, 8 Aug 2011 14:27:03 GMT",
"version": "v3"
},
{
"created": "Wed, 30 Nov 2011 11:33:05 GMT",
"version": "v4"
}
] | 2012-04-01 | [
[
"Zhang",
"Juan",
""
],
[
"Dong",
"Hairong",
""
],
[
"Feng",
"Feng",
""
]
] | We calculate the order-v^2 relativistic correction of J/\psi, including electromagnetic correction, to \chi_{bJ}-> J/\psi J/\psi, in the framework of NRQCD factorization formula. The relativistic order-v^2 effect is found to increase the lower-order prediction for the decay width by about 10%, while the electromagnetism contribution is very small about 0.2% for \chi_{b0} and \chi_{b2}. The total branching ratios are predicted to be of order 10^{-5} for \chi_{b0,b2}-> J/\psi J/\psi, but 10^{-11} for \chi_{b1}-> J/\psi J/\psi, since there is only electromagnetism contribution in this channel. We predict it is possible to observe these reactions in LHC. Finally, we estimate the decay width and branch ratio of \chi_{cJ}-> \omega\omega,\phi\phi) in the constituent quark model by our formula at the leading-order of relativistic correction and electromagnetic correction. The obtained branch ratio of \chi_{c0,2}-> \phi\phi is in agreement with the experimental measurement in the order of magnitude. |
hep-ph/0301199 | Juergen Wentz | J. Wentz, I.M. Brancus, A. Bercuci, D. Heck, J. Oehlschl\"ager, H.
Rebel, B. Vulpescu | Simulation of Atmospheric Muon and Neutrino Fluxes with CORSIKA | revtex, 19 pages, 19 Postscript figures, submitted to Phys. Rev. D | Phys.Rev. D67 (2003) 073020 | 10.1103/PhysRevD.67.073020 | null | hep-ph | null | The fluxes of atmospheric muons and neutrinos are calculated by a three
dimensional Monte Carlo simulation with the air shower code CORSIKA using the
hadronic interaction models DPMJET, VENUS, GHEISHA, and UrQMD. For the
simulation of low energy primary particles the original CORSIKA has been
extended by a parametrization of the solar modulation and a microscopic
calculation of the directional dependence of the geomagnetic cut-off functions.
An accurate description for the geography of the Earth has been included by a
digital elevation model, tables for the local magnetic field in the atmosphere,
and various atmospheric models for different geographic latitudes and annual
seasons. CORSIKA is used to calculate atmospheric muon fluxes for different
locations and the neutrino fluxes for Kamioka. The results of CORSIKA for the
muon fluxes are verified by an extensive comparison with recent measurements.
The obtained neutrino fluxes are compared with other calculations and the
influence of the hadronic interaction model, the geomagnetic cut-off and the
local magnetic field on the neutrino fluxes is investigated.
| [
{
"created": "Thu, 23 Jan 2003 12:36:35 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Feb 2003 15:57:04 GMT",
"version": "v2"
}
] | 2016-08-16 | [
[
"Wentz",
"J.",
""
],
[
"Brancus",
"I. M.",
""
],
[
"Bercuci",
"A.",
""
],
[
"Heck",
"D.",
""
],
[
"Oehlschläger",
"J.",
""
],
[
"Rebel",
"H.",
""
],
[
"Vulpescu",
"B.",
""
]
] | The fluxes of atmospheric muons and neutrinos are calculated by a three dimensional Monte Carlo simulation with the air shower code CORSIKA using the hadronic interaction models DPMJET, VENUS, GHEISHA, and UrQMD. For the simulation of low energy primary particles the original CORSIKA has been extended by a parametrization of the solar modulation and a microscopic calculation of the directional dependence of the geomagnetic cut-off functions. An accurate description for the geography of the Earth has been included by a digital elevation model, tables for the local magnetic field in the atmosphere, and various atmospheric models for different geographic latitudes and annual seasons. CORSIKA is used to calculate atmospheric muon fluxes for different locations and the neutrino fluxes for Kamioka. The results of CORSIKA for the muon fluxes are verified by an extensive comparison with recent measurements. The obtained neutrino fluxes are compared with other calculations and the influence of the hadronic interaction model, the geomagnetic cut-off and the local magnetic field on the neutrino fluxes is investigated. |
hep-ph/0210303 | Mark Strikman | L. Frankfurt (TAU), M. Strikman (PSU), M. Zhalov (PNPI) | Predictions of the Generalized Glauber Model for the coherent
$\rho$-production at RHIC and the STAR data | a typo after Eq.6 is corrected | Phys.Rev.C67:034901,2003 | 10.1103/PhysRevC.67.034901 | null | hep-ph nucl-ex nucl-th | null | We calculate the rapidity distribution and the total cross section of
coherent and incoherent $\rho$-production in the heavy ion ultraperipheral
collisions (UPC) at $\surd s_{NN}=130$ GeV using the generalized vector
dominance model(GVDM) and the Gribov- Glauber approach. We find the coherent
cross section of $\rho $-production $\sigma_{coh}=490$ mb compared to the
$\sigma_{coh}=370\pm 170\pm 80$ mb recently reported by the STAR collaboration
at RHIC. The predicted cross section inside the acceptance of the experiment,
$|y|\le 1$, agrees with the data. It is emphasized that measurements of the
rapidity distribution will provide a much more stringent test of the model.
| [
{
"created": "Wed, 23 Oct 2002 13:05:36 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Oct 2002 15:07:50 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Dec 2002 18:47:06 GMT",
"version": "v3"
}
] | 2011-07-19 | [
[
"Frankfurt",
"L.",
"",
"TAU"
],
[
"Strikman",
"M.",
"",
"PSU"
],
[
"Zhalov",
"M.",
"",
"PNPI"
]
] | We calculate the rapidity distribution and the total cross section of coherent and incoherent $\rho$-production in the heavy ion ultraperipheral collisions (UPC) at $\surd s_{NN}=130$ GeV using the generalized vector dominance model(GVDM) and the Gribov- Glauber approach. We find the coherent cross section of $\rho $-production $\sigma_{coh}=490$ mb compared to the $\sigma_{coh}=370\pm 170\pm 80$ mb recently reported by the STAR collaboration at RHIC. The predicted cross section inside the acceptance of the experiment, $|y|\le 1$, agrees with the data. It is emphasized that measurements of the rapidity distribution will provide a much more stringent test of the model. |
1008.0917 | Stefan Groote | S. Groote, H. Liivat, I. Ots | Symmetries and similarities for spin orientation parameters in e^+ e^-
-> ZH, Z\gamma, ZZ at SM thresholds | 16 pages, 3 figures, published version | Nucl.Phys.B843:213-222,2010 | 10.1016/j.nuclphysb.2010.10.002 | MZ-TH/10-29 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the spin orentation of the final Z bosons for the processes in
the Standard Model. We demonstrate that at the threshold energies of these
processes the analytical expressions for the Z boson polarization vectors and
alignment tensors coincide (e^+ e^- -> ZH, Z\gamma) or are very similar (e^+
e^- -> ZZ). In addition, we present interesting symmetry properties for the
spin orientation parameters.
| [
{
"created": "Thu, 5 Aug 2010 06:27:03 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Oct 2010 07:05:30 GMT",
"version": "v2"
}
] | 2011-03-28 | [
[
"Groote",
"S.",
""
],
[
"Liivat",
"H.",
""
],
[
"Ots",
"I.",
""
]
] | We consider the spin orentation of the final Z bosons for the processes in the Standard Model. We demonstrate that at the threshold energies of these processes the analytical expressions for the Z boson polarization vectors and alignment tensors coincide (e^+ e^- -> ZH, Z\gamma) or are very similar (e^+ e^- -> ZZ). In addition, we present interesting symmetry properties for the spin orientation parameters. |
1212.1304 | Victor Chernyak | Victor L. Chernyak | Hard two photon processes \gamma\gamma --> M_2 M_1 in QCD | 19 pages, 22 figures, talk given at the Taipei International Workshop
"QCD in two photon processes", 2 - 4 October 2012, Taipei, Taiwan | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/3.0/ | A short review of leading term QCD predictions vs those of the handbag model
for large angle cross sections \gamma\gamma --> P_2 P_1 (P is the pseudoscalar
meson \pi^{\pm,o}, K^{\pm,o}, \eta), and for \gamma\gamma --> V_2 V_1 (V is the
neutral vector meson \rho^o, \omega, \phi), in comparison with Belle
Collaboration measuments
| [
{
"created": "Thu, 6 Dec 2012 12:05:42 GMT",
"version": "v1"
}
] | 2012-12-07 | [
[
"Chernyak",
"Victor L.",
""
]
] | A short review of leading term QCD predictions vs those of the handbag model for large angle cross sections \gamma\gamma --> P_2 P_1 (P is the pseudoscalar meson \pi^{\pm,o}, K^{\pm,o}, \eta), and for \gamma\gamma --> V_2 V_1 (V is the neutral vector meson \rho^o, \omega, \phi), in comparison with Belle Collaboration measuments |
2203.00702 | Julian Heeck | Julian Heeck, Robert Szafron, Yuichi Uesaka | Isotope dependence of muon-to-electron conversion | 13 pages, matches NPB version; table included as ancillary file | Nucl. Phys. B 980 (2022) 115833 | 10.1016/j.nuclphysb.2022.115833 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The lepton-flavor-violating conversion of a muon into an electron in the
field of a nucleus is one of the most sensitive probes of physics beyond the
Standard Model and the experiments Mu2e, COMET, and DeeMe will explore
uncharted terrain in the near future. An observation of this $\mu^-\to e^-$
conversion process opens up the possibility to distinguish the underlying
operator or new-physics model by exploiting the target-nucleus dependence of
the conversion rate. To facilitate the choice of optimal targets we provide
$\mu^-\to e^-$ conversion rates for all stable isotopes and estimate
nuclear-structure uncertainties. Our results enable studies of mixed or
enriched target materials that are particularly promising for distinguishing
scenarios in which the muon converts either on protons or neutrons.
| [
{
"created": "Tue, 1 Mar 2022 19:00:08 GMT",
"version": "v1"
},
{
"created": "Mon, 16 May 2022 19:26:36 GMT",
"version": "v2"
}
] | 2022-05-18 | [
[
"Heeck",
"Julian",
""
],
[
"Szafron",
"Robert",
""
],
[
"Uesaka",
"Yuichi",
""
]
] | The lepton-flavor-violating conversion of a muon into an electron in the field of a nucleus is one of the most sensitive probes of physics beyond the Standard Model and the experiments Mu2e, COMET, and DeeMe will explore uncharted terrain in the near future. An observation of this $\mu^-\to e^-$ conversion process opens up the possibility to distinguish the underlying operator or new-physics model by exploiting the target-nucleus dependence of the conversion rate. To facilitate the choice of optimal targets we provide $\mu^-\to e^-$ conversion rates for all stable isotopes and estimate nuclear-structure uncertainties. Our results enable studies of mixed or enriched target materials that are particularly promising for distinguishing scenarios in which the muon converts either on protons or neutrons. |
1605.07164 | Le Tho Hue | K. H. Phan, H.T. Hung, L.T. Hue | One loop contributions to neutral Higgs decay h-->mu tau | Improved version accepted by PTEP. New discussions and references are
added | Prog. Theor. Exp. Phys. (2016) 113B03 | 10.1093/ptep/ptw158 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In calculating one-loop contributions to amplitudes of the lepton-flavor
violating decays of the neutral Higgses (LFVHD) to different flavor charged
leptons, the analytic expressions can be written in term of Passarino-Veltman
functions. Then, they can be computed numerically by Looptools [1]. Another
approach is using suitable analytic expressions established for just this
particular case. We compare numerical results obtained from Looptools and those
computed by different expressions that have been applied recently. Then we
derive the preferable ones that are applicable for the large ranges of free
parameters introduced in the models beyond the Standard Model (SM). For
illustration, the LFVHD in a simple model, which has been discussed recently,
will be investigated more precisely.
| [
{
"created": "Mon, 23 May 2016 19:56:07 GMT",
"version": "v1"
},
{
"created": "Thu, 27 Oct 2016 03:37:12 GMT",
"version": "v2"
}
] | 2016-11-17 | [
[
"Phan",
"K. H.",
""
],
[
"Hung",
"H. T.",
""
],
[
"Hue",
"L. T.",
""
]
] | In calculating one-loop contributions to amplitudes of the lepton-flavor violating decays of the neutral Higgses (LFVHD) to different flavor charged leptons, the analytic expressions can be written in term of Passarino-Veltman functions. Then, they can be computed numerically by Looptools [1]. Another approach is using suitable analytic expressions established for just this particular case. We compare numerical results obtained from Looptools and those computed by different expressions that have been applied recently. Then we derive the preferable ones that are applicable for the large ranges of free parameters introduced in the models beyond the Standard Model (SM). For illustration, the LFVHD in a simple model, which has been discussed recently, will be investigated more precisely. |
1909.04994 | Xun Chen Mr | Yan-Qing Zhao, Zhou-Run Zhu and Xun Chen | The effect of gluon condensate on imaginary potential and thermal width
from holography | 6 pages, 6 figures | null | 10.1140/epja/s10050-020-00072-5 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By the use of the gauge/gravity duality, we calculate the imaginary part of
heavy quarkonium potential and thermal width with the effect of gluon
condensate which is absent in AdS$_{5}$ background. Our results show that the
dropping gluon condensate reduces the absolute value of imaginary potential and
therefore decreases the thermal width both in "exact" and "approximate"
approach implying that the heavy quarkonium has a weaker bound with the
increase of gluon condensate. In addition, the thermal width will disappear at
a critical condensate value, which indicates the dissociation of quarkonium. We
conclude that increasing gluon condensate will lead to easier dissociation of
heavy quarkonium for fixed temperature.
| [
{
"created": "Wed, 11 Sep 2019 12:05:00 GMT",
"version": "v1"
},
{
"created": "Sat, 2 Nov 2019 10:09:25 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Mar 2020 02:30:41 GMT",
"version": "v3"
}
] | 2020-03-18 | [
[
"Zhao",
"Yan-Qing",
""
],
[
"Zhu",
"Zhou-Run",
""
],
[
"Chen",
"Xun",
""
]
] | By the use of the gauge/gravity duality, we calculate the imaginary part of heavy quarkonium potential and thermal width with the effect of gluon condensate which is absent in AdS$_{5}$ background. Our results show that the dropping gluon condensate reduces the absolute value of imaginary potential and therefore decreases the thermal width both in "exact" and "approximate" approach implying that the heavy quarkonium has a weaker bound with the increase of gluon condensate. In addition, the thermal width will disappear at a critical condensate value, which indicates the dissociation of quarkonium. We conclude that increasing gluon condensate will lead to easier dissociation of heavy quarkonium for fixed temperature. |
0903.4409 | James Gainer | R. C. Cotta, J. S. Gainer, J. L. Hewett, T. G. Rizzo | Dark Matter in the MSSM | 27 pages, 19 figs; Journal version in NJP issue "Focus on Dark Matter
and Particle Physics". Previous version had 26 pages, 19 figures. Text and
some figures have been updated | New J.Phys.11:105026,2009 | 10.1088/1367-2630/11/10/105026 | SLAC-PUB-13562 | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have recently examined a large number of points in the parameter space of
the phenomenological MSSM, the 19-dimensional parameter space of the
CP-conserving MSSM with Minimal Flavor Violation. We determined whether each of
these points satisfied existing experimental and theoretical constraints. This
analysis provides insight into general features of the MSSM without reference
to a particular SUSY breaking scenario or any other assumptions at the GUT
scale. This study opens up new possibilities for SUSY phenomenology both in
colliders and in astrophysical experiments. Here we shall discuss the
implications of this analysis relevant to the study of dark matter.
| [
{
"created": "Wed, 25 Mar 2009 17:53:06 GMT",
"version": "v1"
},
{
"created": "Sat, 24 Oct 2009 02:01:28 GMT",
"version": "v2"
}
] | 2014-11-18 | [
[
"Cotta",
"R. C.",
""
],
[
"Gainer",
"J. S.",
""
],
[
"Hewett",
"J. L.",
""
],
[
"Rizzo",
"T. G.",
""
]
] | We have recently examined a large number of points in the parameter space of the phenomenological MSSM, the 19-dimensional parameter space of the CP-conserving MSSM with Minimal Flavor Violation. We determined whether each of these points satisfied existing experimental and theoretical constraints. This analysis provides insight into general features of the MSSM without reference to a particular SUSY breaking scenario or any other assumptions at the GUT scale. This study opens up new possibilities for SUSY phenomenology both in colliders and in astrophysical experiments. Here we shall discuss the implications of this analysis relevant to the study of dark matter. |
1810.00016 | Mikhail Mikhasenko | JPAC Collaboration: M.Mikhasenko, A.Pilloni, M.Albaladejo,
C.Fernandez-Ramirez, A.Jackura, V.Mathieu, J.Nys, A.Rodas, B.Ketzer,
A.P.Szczepaniak | Pole position of the $a_1(1260)$ from $\tau$-decay | 20 pages, 22 figures | Phys. Rev. D 98, 096021 (2018) | 10.1103/PhysRevD.98.096021 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform an analysis of the three-pion system with quantum numbers
$J^{PC}=1^{++}$ produced in the weak decay of $\tau$ leptons. The interaction
is known to be dominated by the axial meson $a_1(1260)$. We build a model based
on approximate three-body unitarity and fix the free parameters by fitting it
to the ALEPH data on $\tau^-\to \pi^-\pi^+\pi^-\,\nu_\tau$ decay. We then
perform the analytic continuation of the amplitude to the complex energy plane.
The singularity structures related to the $\pi\pi$ subchannel resonances are
carefully addressed. Finally, we extract the $a_1(1260)$ pole position
$m_p^{(a_1(1260))}-i\Gamma_p^{(a_1(1260))}/2$ with $m_p^{(a_1(1260))} = (1209
\pm 4^{+12}_{-9})\text{MeV}$, $\Gamma_p^{(a_1(1260))} = (576 \pm 11
^{+89}_{-20})\text{MeV}$}.
| [
{
"created": "Fri, 28 Sep 2018 18:01:15 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Jan 2019 09:18:13 GMT",
"version": "v2"
}
] | 2019-01-11 | [
[
"JPAC Collaboration",
"",
""
],
[
"Mikhasenko",
"M.",
""
],
[
"Pilloni",
"A.",
""
],
[
"Albaladejo",
"M.",
""
],
[
"Fernandez-Ramirez",
"C.",
""
],
[
"Jackura",
"A.",
""
],
[
"Mathieu",
"V.",
""
],
[
... | We perform an analysis of the three-pion system with quantum numbers $J^{PC}=1^{++}$ produced in the weak decay of $\tau$ leptons. The interaction is known to be dominated by the axial meson $a_1(1260)$. We build a model based on approximate three-body unitarity and fix the free parameters by fitting it to the ALEPH data on $\tau^-\to \pi^-\pi^+\pi^-\,\nu_\tau$ decay. We then perform the analytic continuation of the amplitude to the complex energy plane. The singularity structures related to the $\pi\pi$ subchannel resonances are carefully addressed. Finally, we extract the $a_1(1260)$ pole position $m_p^{(a_1(1260))}-i\Gamma_p^{(a_1(1260))}/2$ with $m_p^{(a_1(1260))} = (1209 \pm 4^{+12}_{-9})\text{MeV}$, $\Gamma_p^{(a_1(1260))} = (576 \pm 11 ^{+89}_{-20})\text{MeV}$}. |
hep-ph/0211152 | David Rayner | V. Di Clemente, S. F. King and D. A. J. Rayner | Supersymmetric Higgs Bosons in a 5D Orbifold Model | 5 pages, 3 eps figures, ws-procs9x6.cls included. Based on a talk
given by V.D.C. at 1st International Conference on String Phenomenology,
Oxford, England, 6-11 Jul 2002 | null | null | SHEP 02-31 | hep-ph | null | We analyze the phenomenology of the Higgs sector in a 5D model compactified
on an $S_1/Z_2$ orbifold with a compactification scale $M_C \sim {\mathcal
O}(TeV)$ where supersymmetry breaking is localized on a brane at one of the
fixed points. We show that the conventional MSSM Higgs boson mass bounds in 4D
can be violated when we allow the gauge sector, Higgs and third family
multiplets to live in the fifth extra dimension.
| [
{
"created": "Mon, 11 Nov 2002 14:38:45 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Di Clemente",
"V.",
""
],
[
"King",
"S. F.",
""
],
[
"Rayner",
"D. A. J.",
""
]
] | We analyze the phenomenology of the Higgs sector in a 5D model compactified on an $S_1/Z_2$ orbifold with a compactification scale $M_C \sim {\mathcal O}(TeV)$ where supersymmetry breaking is localized on a brane at one of the fixed points. We show that the conventional MSSM Higgs boson mass bounds in 4D can be violated when we allow the gauge sector, Higgs and third family multiplets to live in the fifth extra dimension. |
1509.04164 | Junya Nakamura | Junya Nakamura | A simple merging algorithm for jet angular correlation studies | 15 pages, 2 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A tree level merging algorithm which guarantees the leading order (LO)
accuracy of angular correlations between jets is proposed and studied. The
algorithm is designed so that n-jet events are generated exclusively according
to the LO n-parton production cross section and each of the n-jet is close to
each of the n-parton in terms of the jet measure. As a result, the LO accuracy
of angular correlations between the n-jet is robust. Furthermore, as long as
the n-jet events are exclusively subjects to a study, only the LO n-parton
production cross section is needed and hence event generation is efficient.
Correlations in the azimuthal angle difference between the two highest
transverse momentum jets with large rapidity separations in the top quark pair
production are evaluated as examples. The algorithm is validated by discussing
numerical differences between its predictions and the predictions of a
well-established merging algorithm.
| [
{
"created": "Mon, 14 Sep 2015 15:43:12 GMT",
"version": "v1"
}
] | 2015-09-15 | [
[
"Nakamura",
"Junya",
""
]
] | A tree level merging algorithm which guarantees the leading order (LO) accuracy of angular correlations between jets is proposed and studied. The algorithm is designed so that n-jet events are generated exclusively according to the LO n-parton production cross section and each of the n-jet is close to each of the n-parton in terms of the jet measure. As a result, the LO accuracy of angular correlations between the n-jet is robust. Furthermore, as long as the n-jet events are exclusively subjects to a study, only the LO n-parton production cross section is needed and hence event generation is efficient. Correlations in the azimuthal angle difference between the two highest transverse momentum jets with large rapidity separations in the top quark pair production are evaluated as examples. The algorithm is validated by discussing numerical differences between its predictions and the predictions of a well-established merging algorithm. |
hep-ph/9903421 | A. Khodjamirian | A. Khodjamirian, R. R\"uckl, S. Weinzierl, O.Yakovlev | Perturbative QCD Correction to the Light-Cone Sum Rule for the $B^*B\pi
$ and $D^*D\pi$ Couplings | 11 pages, 1 figure, Latex, epsfig | Phys.Lett. B457 (1999) 245-252 | 10.1016/S0370-2693(99)00518-3 | WUE-ITP-98-043 | hep-ph | null | The $B^*B\pi$ and $D^*D\pi$ couplings have previously been derived from a QCD
light-cone sum rule in leading order. Here, we describe the calculation of the
$O(\alpha_s)$ correction to the twist 2 term of this sum rule. The result is
used for a first next-to-leading order analysis. We obtain $g_{B^*B\pi}= 22\pm
7$ and $g_{D^*D\pi}=10.5\pm 3$, where the error indicates the remaining
theoretical uncertainty.
| [
{
"created": "Sat, 20 Mar 1999 20:44:24 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Khodjamirian",
"A.",
""
],
[
"Rückl",
"R.",
""
],
[
"Weinzierl",
"S.",
""
],
[
"Yakovlev",
"O.",
""
]
] | The $B^*B\pi$ and $D^*D\pi$ couplings have previously been derived from a QCD light-cone sum rule in leading order. Here, we describe the calculation of the $O(\alpha_s)$ correction to the twist 2 term of this sum rule. The result is used for a first next-to-leading order analysis. We obtain $g_{B^*B\pi}= 22\pm 7$ and $g_{D^*D\pi}=10.5\pm 3$, where the error indicates the remaining theoretical uncertainty. |
hep-ph/0202013 | Subir Sarkar | Subir Sarkar (Oxford U.) | Ultra-high energy cosmic rays and new physics | 15 pages (LaTeX), 6 figures; Invited talk at COSMO-01 Workshop,
Rovaniemi, Finland, August 30-September 4, 2001; Changes: typos fixed,
references added | null | null | null | hep-ph astro-ph | null | Cosmic rays with energies beyond the Greisen-Zatsepin-Kuzmin `cutoff' at
$\sim 4 \times 10^{10}$ GeV pose a conundrum, the solution of which requires
either drastic revision of our astrophysical understanding, or new physics
beyond the Standard Model. Nucleons of such energies must originate within the
local supercluster in order to avoid excessive energy losses through photopion
production on the cosmic microwave background. However they do not point back
towards possible nearby sources, e.g. the active galaxy Cen A or M87 in the
Virgo cluster, so such an astrophysical origin requires intergalactic magnetic
fields to be a hundred times stronger than previously believed, in order to
isotropise their arrival directions. Alternatively the primaries may be high
energy neutrinos, say from distant gamma-ray bursts, which annihilate on the
local relic background neutrinos to create ``Z-bursts''. A related possibility
is that the primary neutinos may initiate the observed air showers directly if
their interaction cross-sections are boosted to hadronic strength through
non-perturbative physics such as TeV-scale quantum gravity. Or the primaries
may instead be new strongly interacting neutral particles with a longer mean
free path than nucleons, coming perhaps from distant BL-Lac objects or FR-II
radio galaxies. Yet another possibility is that Lorentz invariance is violated
at high energies thus suppressing the energy loss processes altogether. The
idea that has perhaps been studied in most detail is that such cosmic rays
originate from the decays of massive relic particles (``wimpzillas'') clustered
as dark matter in the galactic halo. All these hypotheses will soon be
critically tested by the Pierre Auger Observatory, presently under construction
in Argentina, and by proposed satellite experiments such as EUSO.
| [
{
"created": "Sun, 3 Feb 2002 23:47:20 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Feb 2002 16:09:32 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Sarkar",
"Subir",
"",
"Oxford U."
]
] | Cosmic rays with energies beyond the Greisen-Zatsepin-Kuzmin `cutoff' at $\sim 4 \times 10^{10}$ GeV pose a conundrum, the solution of which requires either drastic revision of our astrophysical understanding, or new physics beyond the Standard Model. Nucleons of such energies must originate within the local supercluster in order to avoid excessive energy losses through photopion production on the cosmic microwave background. However they do not point back towards possible nearby sources, e.g. the active galaxy Cen A or M87 in the Virgo cluster, so such an astrophysical origin requires intergalactic magnetic fields to be a hundred times stronger than previously believed, in order to isotropise their arrival directions. Alternatively the primaries may be high energy neutrinos, say from distant gamma-ray bursts, which annihilate on the local relic background neutrinos to create ``Z-bursts''. A related possibility is that the primary neutinos may initiate the observed air showers directly if their interaction cross-sections are boosted to hadronic strength through non-perturbative physics such as TeV-scale quantum gravity. Or the primaries may instead be new strongly interacting neutral particles with a longer mean free path than nucleons, coming perhaps from distant BL-Lac objects or FR-II radio galaxies. Yet another possibility is that Lorentz invariance is violated at high energies thus suppressing the energy loss processes altogether. The idea that has perhaps been studied in most detail is that such cosmic rays originate from the decays of massive relic particles (``wimpzillas'') clustered as dark matter in the galactic halo. All these hypotheses will soon be critically tested by the Pierre Auger Observatory, presently under construction in Argentina, and by proposed satellite experiments such as EUSO. |
1904.08271 | Wei-Hong Liang | Sheng-Juan Jiang, S. Sakai, Wei-Hong Liang, E. Oset | The $\chi_{cJ}$ decay to $\phi K^* \bar K, \phi h_1(1380)$ testing the
nature of axial vector meson resonances | 11 pages, 3 figures; V2: version accepted for publication in Phys.
Lett. B | null | 10.1016/j.physletb.2019.134831 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a theoretical study of the $\chi_{cJ} \to \phi K^* \bar K \to \phi
K\pi \bar K$ reaction taking into account the $K^* \bar K$ final state
interaction, which in the chiral unitary approach is responsible, together with
its coupled channels, for the formation of the low lying axial vector mesons,
in this case the $h_1(1380)$ given the selection of quantum numbers. Based on
this picture we can easily explain why in the $\chi_{c0}$ decay the $h_1(1380)$
resonance is not produced, and, in the case of $\chi_{c1}$ and $\chi_{c2}$
decay, why a dip in the $K^+ \pi^0 K^-$ mass distribution appears in the
1550-1600 MeV region, that in our picture comes from a destructive interference
between the tree level mechanism and the rescattering that generates the
$h_1(1380)$ state. Such a dip is not reproduced in pictures where the nominal
$h_1(1380)$ signal is added incoherently to a background, which provides
support to the picture where the resonance appears from rescattering of
vector-pseudoscalar components.
| [
{
"created": "Wed, 17 Apr 2019 13:43:30 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Aug 2019 15:45:07 GMT",
"version": "v2"
}
] | 2019-08-14 | [
[
"Jiang",
"Sheng-Juan",
""
],
[
"Sakai",
"S.",
""
],
[
"Liang",
"Wei-Hong",
""
],
[
"Oset",
"E.",
""
]
] | We perform a theoretical study of the $\chi_{cJ} \to \phi K^* \bar K \to \phi K\pi \bar K$ reaction taking into account the $K^* \bar K$ final state interaction, which in the chiral unitary approach is responsible, together with its coupled channels, for the formation of the low lying axial vector mesons, in this case the $h_1(1380)$ given the selection of quantum numbers. Based on this picture we can easily explain why in the $\chi_{c0}$ decay the $h_1(1380)$ resonance is not produced, and, in the case of $\chi_{c1}$ and $\chi_{c2}$ decay, why a dip in the $K^+ \pi^0 K^-$ mass distribution appears in the 1550-1600 MeV region, that in our picture comes from a destructive interference between the tree level mechanism and the rescattering that generates the $h_1(1380)$ state. Such a dip is not reproduced in pictures where the nominal $h_1(1380)$ signal is added incoherently to a background, which provides support to the picture where the resonance appears from rescattering of vector-pseudoscalar components. |
hep-ph/0209310 | Tai-Fu Feng | Tai-Fu Feng, Xue-Qian Li, Yan-An Luo | Neutrinoless Double Beta Decay in Supersymmetric Seesaw model | latex, 25 pages, include 5 figures, final version in Phys. Rev. D | Phys.Rev. D66 (2002) 056011 | 10.1103/PhysRevD.66.056011 | BIHEP-TH-2002-33 | hep-ph | null | Inspired by the recent HEIDELBERG-MOSCOW double beta decay experiment, we
discuss the neutrinoless double beta decay in the supersymmetric seesaw model.
Our numerical analysis indicates that we can naturally explain the data of the
observed neutrinoless double beta decay, as well as that of the solar and
atmospheric neutrino experiments with at least one Majorana-like sneutrino of
middle energy scale in the model.
| [
{
"created": "Thu, 26 Sep 2002 02:24:23 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Feng",
"Tai-Fu",
""
],
[
"Li",
"Xue-Qian",
""
],
[
"Luo",
"Yan-An",
""
]
] | Inspired by the recent HEIDELBERG-MOSCOW double beta decay experiment, we discuss the neutrinoless double beta decay in the supersymmetric seesaw model. Our numerical analysis indicates that we can naturally explain the data of the observed neutrinoless double beta decay, as well as that of the solar and atmospheric neutrino experiments with at least one Majorana-like sneutrino of middle energy scale in the model. |
2206.01148 | Ziyan Yuwen | Shao-Jiang Wang, Zi-Yan Yuwen | The energy budget of cosmological first-order phase transitions beyond
the bag equation of state | 34 pages, 9 figures | JCAP10(2022)047 | 10.1088/1475-7516/2022/10/047 | null | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The stochastic gravitational-wave backgrounds (SGWBs) from the cosmological
first-order phase transitions (FOPTs) serve as a promising probe for the new
physics beyond the standard model of particle physics. When most of the bubble
walls collide with each other long after they had reached the terminal wall
velocity, the dominated contribution to the SGWBs comes from the sound waves
characterized by the efficiency factor of inserting the released vacuum energy
into the bulk fluid motions. However, the previous works of estimating this
efficiency factor have only considered the simplified case of the constant
sound velocities in both symmetric and broken phases, either for the bag model
with equal sound velocities or $\nu$-model with different sound velocities in
the symmetric and broken phases, which is unrealistic from a viewpoint of
particle physics. In this paper, we propose to solve the fluid EoM with an
iteration method when taking into account the sound-velocity variation across
the bubble wall for a general and realistic equation of state (EoS) beyond the
simple bag model and $\nu$-model. We have found a suppression effect for the
efficiency factor of bulk fluid motions, though such a suppression effect could
be negligible for the strong FOPT, in which case the previous estimation from a
bag EoS on the efficiency factor of bulk fluid motions still works as a good
approximation.
| [
{
"created": "Thu, 2 Jun 2022 16:58:32 GMT",
"version": "v1"
},
{
"created": "Sat, 15 Oct 2022 10:54:10 GMT",
"version": "v2"
}
] | 2022-10-18 | [
[
"Wang",
"Shao-Jiang",
""
],
[
"Yuwen",
"Zi-Yan",
""
]
] | The stochastic gravitational-wave backgrounds (SGWBs) from the cosmological first-order phase transitions (FOPTs) serve as a promising probe for the new physics beyond the standard model of particle physics. When most of the bubble walls collide with each other long after they had reached the terminal wall velocity, the dominated contribution to the SGWBs comes from the sound waves characterized by the efficiency factor of inserting the released vacuum energy into the bulk fluid motions. However, the previous works of estimating this efficiency factor have only considered the simplified case of the constant sound velocities in both symmetric and broken phases, either for the bag model with equal sound velocities or $\nu$-model with different sound velocities in the symmetric and broken phases, which is unrealistic from a viewpoint of particle physics. In this paper, we propose to solve the fluid EoM with an iteration method when taking into account the sound-velocity variation across the bubble wall for a general and realistic equation of state (EoS) beyond the simple bag model and $\nu$-model. We have found a suppression effect for the efficiency factor of bulk fluid motions, though such a suppression effect could be negligible for the strong FOPT, in which case the previous estimation from a bag EoS on the efficiency factor of bulk fluid motions still works as a good approximation. |
1411.2843 | Max Zoller | Max F. Zoller | Standard Model beta-functions to three-loop order and vacuum stability | Contribution to the proceedings of the 42nd ITEP Winter School of
Physics, Moscow | null | null | TTP14-030, SFB/CPP-14-87 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Since the discovery of a Higgs particle the effective Higgs potential of the
Standard Model or extensions and the stability of the ground state
corresponding to its minimum at the electroweak scale have been subject to a
lot of investigation. The vacuum expectation value of the scalar SU(2) doublet
field in the Standard Model, which is responsible for the masses of elementary
particles, may in fact not be at the global minimum of the effective Higgs
potential. The question whether there is a deeper minimum at some large scale
is closely linked to the behaviour of the running quartic Higgs
self-interaction $\lambda(\mu)$. In this talk an update on the analysis of the
evolution of this coupling is given. We use three-loop beta-functions for the
Standard Model couplings, two-loop matching between on-shell and MSbar
quantities and compare the theoretical precision achieved in this way to the
precision in the latest experimental values for the key parameters.
| [
{
"created": "Tue, 11 Nov 2014 15:05:25 GMT",
"version": "v1"
}
] | 2014-11-12 | [
[
"Zoller",
"Max F.",
""
]
] | Since the discovery of a Higgs particle the effective Higgs potential of the Standard Model or extensions and the stability of the ground state corresponding to its minimum at the electroweak scale have been subject to a lot of investigation. The vacuum expectation value of the scalar SU(2) doublet field in the Standard Model, which is responsible for the masses of elementary particles, may in fact not be at the global minimum of the effective Higgs potential. The question whether there is a deeper minimum at some large scale is closely linked to the behaviour of the running quartic Higgs self-interaction $\lambda(\mu)$. In this talk an update on the analysis of the evolution of this coupling is given. We use three-loop beta-functions for the Standard Model couplings, two-loop matching between on-shell and MSbar quantities and compare the theoretical precision achieved in this way to the precision in the latest experimental values for the key parameters. |
1911.03111 | Rafiqul Rahaman | Rafiqul Rahaman and Ritesh K. Singh | Unravelling the anomalous gauge boson couplings in $ZW^\pm$ production
at the LHC and the role of spin-$1$ polarizations | 32 pages, 13 figures and 6 tables | null | 10.1007/JHEP04(2020)075 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the anomalous triple gauge boson couplings (aTGC) in $ZW^\pm$
production in $3l$ + missing $E_T$ channel at the LHC for $\sqrt{s}=13$ TeV. We
use cross sections, azimuthal asymmetry, forward-backward asymmetry, and
polarization asymmetries of $Z$ and reconstructed $W$ to estimate simultaneous
limits on the anomalous couplings for both the effective vertex formalism as
well as the effective operator approach using the Markov-chain--Monte-Carlo
(MCMC) method for luminosities $35.9$ fb$^{-1}$, $100$ fb$^{-1}$, $300$
fb$^{-1}$, $1000$ fb$^{-1}$, and $3000$ fb$^{-1}$. The trilepton invariant mass
($m_{3l}$)and the transverse momentum of $Z$ ($p_T(Z)$) are found to be
sensitive to the aTGC for the cross sections as well as for the asymmetries. We
observed that the asymmetries significantly improve the measurement of
anomalous couplings at the high-luminosity large hadron collider (LHC) if a
deviation from the Standard Model (SM) is observed.
| [
{
"created": "Fri, 8 Nov 2019 08:01:28 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Jul 2020 07:52:12 GMT",
"version": "v2"
}
] | 2020-07-16 | [
[
"Rahaman",
"Rafiqul",
""
],
[
"Singh",
"Ritesh K.",
""
]
] | We study the anomalous triple gauge boson couplings (aTGC) in $ZW^\pm$ production in $3l$ + missing $E_T$ channel at the LHC for $\sqrt{s}=13$ TeV. We use cross sections, azimuthal asymmetry, forward-backward asymmetry, and polarization asymmetries of $Z$ and reconstructed $W$ to estimate simultaneous limits on the anomalous couplings for both the effective vertex formalism as well as the effective operator approach using the Markov-chain--Monte-Carlo (MCMC) method for luminosities $35.9$ fb$^{-1}$, $100$ fb$^{-1}$, $300$ fb$^{-1}$, $1000$ fb$^{-1}$, and $3000$ fb$^{-1}$. The trilepton invariant mass ($m_{3l}$)and the transverse momentum of $Z$ ($p_T(Z)$) are found to be sensitive to the aTGC for the cross sections as well as for the asymmetries. We observed that the asymmetries significantly improve the measurement of anomalous couplings at the high-luminosity large hadron collider (LHC) if a deviation from the Standard Model (SM) is observed. |
hep-ph/9605393 | Andreas Blumhofer | Andreas Blumhofer and Marcus Hutter | Family Structure from Periodic Solutions of an Improved Gap Equation | 19 pages, 8 figures | Nucl.Phys. B484 (1997) 80-96; Erratum-ibid. B494 (1997) 485 | 10.1016/S0550-3213(97)00228-9 | LMU-05/96 | hep-ph | null | Fermion mass models usually contain a horizontal symmetry and therefore fail
to predict the exponential mass spectrum of the Standard Model in a natural
way. In dynamical symmetry breaking there are different concepts to introduce a
fermion mass spectrum, which automatically has the desired hierarchy. In
constructing a specific model we show that in some modified gap equations
periodic solutions with several fermion poles appear. The stability of these
excitations and the application of this toy model are discussed. The mass
ratios turn out to be approximately $e^\pi$ and $e^{2\pi}$. Thus the model
explains the large ratios of fermion masses between successive generations in
the Standard Model without introducing large or small numbers by hand.
| [
{
"created": "Fri, 24 May 1996 14:11:56 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Blumhofer",
"Andreas",
""
],
[
"Hutter",
"Marcus",
""
]
] | Fermion mass models usually contain a horizontal symmetry and therefore fail to predict the exponential mass spectrum of the Standard Model in a natural way. In dynamical symmetry breaking there are different concepts to introduce a fermion mass spectrum, which automatically has the desired hierarchy. In constructing a specific model we show that in some modified gap equations periodic solutions with several fermion poles appear. The stability of these excitations and the application of this toy model are discussed. The mass ratios turn out to be approximately $e^\pi$ and $e^{2\pi}$. Thus the model explains the large ratios of fermion masses between successive generations in the Standard Model without introducing large or small numbers by hand. |
0810.3889 | Chong Sheng Li | Jia Jun Zhang, Chong Sheng Li, Jun Gao, Hao Zhang, Zhao Li, C.-P. Yuan
and Tzu-Chiang Yuan | Next-to-leading order QCD corrections to the top quark decay via
model-independent FCNC couplings | 4 pages, 3 figures, minor changes, typos corrected | Phys.Rev.Lett.102:072001,2009 | 10.1103/PhysRevLett.102.072001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | D0 and CDF collaborations at the Fermilab Tevatron have searched for
non-standard-model single top-quark production and set upper limits on the
anomalous top quark flavor-changing neutral current (FCNC) couplings
$\kappa^g_{tc}/\Lambda$ and $\kappa^g_{tu}/\Lambda$ using the measurement of
total cross section calculated at the next-to-leading order (NLO) in QCD. In
this Letter, we report on the effect of anomalous FCNC couplings to various
decay branching ratios of the top quark, calculated at the NLO. This result is
not only mandatory for a consistent treatment of both the top quark production
and decay via FCNC couplings by D0 and CDF at the Tevatron but is also
important for the study of ATLAS and CMS sensitivity to these anomalous
couplings at the CERN LHC. We find that the NLO corrections to the partial
decay widths of the three decay channels $ t\to q + g$, $ t\to q + \gamma$ and
$ t\to q + Z$ are at the order of 10% in magnitude and modify their branching
ratios by about 20%, 0.4% and 2%, respectively, as compared to their leading
order predictions.
| [
{
"created": "Tue, 21 Oct 2008 18:10:05 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Oct 2008 16:39:34 GMT",
"version": "v2"
},
{
"created": "Wed, 5 Nov 2008 10:25:07 GMT",
"version": "v3"
},
{
"created": "Sat, 3 Jan 2009 14:55:54 GMT",
"version": "v4"
}
] | 2009-02-27 | [
[
"Zhang",
"Jia Jun",
""
],
[
"Li",
"Chong Sheng",
""
],
[
"Gao",
"Jun",
""
],
[
"Zhang",
"Hao",
""
],
[
"Li",
"Zhao",
""
],
[
"Yuan",
"C. -P.",
""
],
[
"Yuan",
"Tzu-Chiang",
""
]
] | D0 and CDF collaborations at the Fermilab Tevatron have searched for non-standard-model single top-quark production and set upper limits on the anomalous top quark flavor-changing neutral current (FCNC) couplings $\kappa^g_{tc}/\Lambda$ and $\kappa^g_{tu}/\Lambda$ using the measurement of total cross section calculated at the next-to-leading order (NLO) in QCD. In this Letter, we report on the effect of anomalous FCNC couplings to various decay branching ratios of the top quark, calculated at the NLO. This result is not only mandatory for a consistent treatment of both the top quark production and decay via FCNC couplings by D0 and CDF at the Tevatron but is also important for the study of ATLAS and CMS sensitivity to these anomalous couplings at the CERN LHC. We find that the NLO corrections to the partial decay widths of the three decay channels $ t\to q + g$, $ t\to q + \gamma$ and $ t\to q + Z$ are at the order of 10% in magnitude and modify their branching ratios by about 20%, 0.4% and 2%, respectively, as compared to their leading order predictions. |
1308.1426 | Thomas J. Weiler | Thomas J. Weiler (Vanderbilt University) | Likely Dominance of WIMP Annihilation to Fermion Pair + W/Z | Talk presented at ICRC2013, July 2-9, Rio de Janeiro, Brazil; 4
pages, includes two paneled figures and two tables | null | null | null | hep-ph astro-ph.CO astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Arguably, the most popular candidate for Dark Matter (DM) is a massive,
stable, Majorana fermion. However, annihilation of Majorana DM to two fermions
features a helicity-suppressed s-wave rate. The process radiating a gauge boson
via electroweak (EW) and electromagnetic (EM) bremsstrahlung removes this
s-wave suppression, and is likely to be the dominant modes of gauge-singlet
Majorana DM annihilation. Given their enhanced annihilation rate with radiatedW
and Z gauge bosons, and the subsequent dominant W/Z decays via hadronic
channels, Majorana DM tends to produce more antiprotons than positrons. This
result contrasts with observations, thereby presenting a challenge to model
building with Majorana DM.
| [
{
"created": "Tue, 6 Aug 2013 21:37:53 GMT",
"version": "v1"
}
] | 2013-08-08 | [
[
"Weiler",
"Thomas J.",
"",
"Vanderbilt University"
]
] | Arguably, the most popular candidate for Dark Matter (DM) is a massive, stable, Majorana fermion. However, annihilation of Majorana DM to two fermions features a helicity-suppressed s-wave rate. The process radiating a gauge boson via electroweak (EW) and electromagnetic (EM) bremsstrahlung removes this s-wave suppression, and is likely to be the dominant modes of gauge-singlet Majorana DM annihilation. Given their enhanced annihilation rate with radiatedW and Z gauge bosons, and the subsequent dominant W/Z decays via hadronic channels, Majorana DM tends to produce more antiprotons than positrons. This result contrasts with observations, thereby presenting a challenge to model building with Majorana DM. |
0810.3899 | Vadim Guzey | V. Guzey (Jefferson Lab), T. Teckentrup (Ruhr U., Bochum) | On the mistake in the implementation of the minimal model of the dual
parameterization and resulting inability to describe the high-energy DVCS
data | 8 pages, 1 figure | Phys.Rev.D79:017501,2009 | 10.1103/PhysRevD.79.017501 | JLAB-THY-08-897 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We correct the mistaken claim made in \cite{Guzey:2005ec,Guzey:2006xi} that
the minimal model of the dual parameterization of nucleon generalized parton
distributions (GPDs) gives a good, essentially model-independent description of
high-energy data on deeply virtual Compton scattering (DVCS). In the
implementation of the dual parameterization in
\cite{Guzey:2005ec,Guzey:2006xi}, the numerical prefactor of two in front of
the DVCS amplitude was missing. We show that the corrected minimal model of the
dual parameterization significantly overestimates the HERA data (H1 and ZEUS)
on the DVCS cross section.
| [
{
"created": "Tue, 21 Oct 2008 18:55:33 GMT",
"version": "v1"
}
] | 2009-01-16 | [
[
"Guzey",
"V.",
"",
"Jefferson Lab"
],
[
"Teckentrup",
"T.",
"",
"Ruhr U., Bochum"
]
] | We correct the mistaken claim made in \cite{Guzey:2005ec,Guzey:2006xi} that the minimal model of the dual parameterization of nucleon generalized parton distributions (GPDs) gives a good, essentially model-independent description of high-energy data on deeply virtual Compton scattering (DVCS). In the implementation of the dual parameterization in \cite{Guzey:2005ec,Guzey:2006xi}, the numerical prefactor of two in front of the DVCS amplitude was missing. We show that the corrected minimal model of the dual parameterization significantly overestimates the HERA data (H1 and ZEUS) on the DVCS cross section. |
0811.1812 | Yonglu Liu | Yong-Lu Liu and Ming-Qiu Huang | Distribution amplitudes of $\Sigma$ and $\Lambda$ and their
electromagnetic form factors | 40 pages, 19 figures | Nucl.Phys.A821:80-105, 2009 | 10.1016/j.nuclphysa.2009.02.003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based on QCD conformal partial wave expansion to leading order conformal spin
accuracy, we present the light-cone distribution amplitudes (DAs) of $\Sigma$
and $\Lambda$ baryons up to twist 6. It is concluded that fourteen ndependent
DAs are needed to describe the valence three-quark states of the baryons at
small transverse separations. The nonperturbative parameters relevant to the
DAs are determined within the framework of QCD sum rule method. With the
obtained DAs, a simple investigation on the electromagnetic form factors of
these baryons are given. The magnetic moments of the baryons are estimated by
fitting the magnetic form factor with the dipole formula.
| [
{
"created": "Wed, 12 Nov 2008 03:44:20 GMT",
"version": "v1"
},
{
"created": "Sat, 21 Mar 2009 04:50:12 GMT",
"version": "v2"
}
] | 2009-03-24 | [
[
"Liu",
"Yong-Lu",
""
],
[
"Huang",
"Ming-Qiu",
""
]
] | Based on QCD conformal partial wave expansion to leading order conformal spin accuracy, we present the light-cone distribution amplitudes (DAs) of $\Sigma$ and $\Lambda$ baryons up to twist 6. It is concluded that fourteen ndependent DAs are needed to describe the valence three-quark states of the baryons at small transverse separations. The nonperturbative parameters relevant to the DAs are determined within the framework of QCD sum rule method. With the obtained DAs, a simple investigation on the electromagnetic form factors of these baryons are given. The magnetic moments of the baryons are estimated by fitting the magnetic form factor with the dipole formula. |
1012.2806 | Pere Masjuan | Pere Masjuan | Hunting resonance poles with Rational Approximants | 8 pages, 4 figures. This letter partially covers the material
presented by the author at the 15th International QCD Conference: QCD 10
(25th anniversary), Montpellier, France, 28 Jun - 3 Jul 2010 and at the Quark
Confinement and the Hadron Spectrum IX, 30 August - 3 September 2010, Madrid,
Spain | null | null | UGFT-279/10, CAFPE-149/10 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based on the mathematically well defined Pad\'e Theory, a theoretically safe
new procedure for the extraction of the pole mass and width of resonances is
proposed. In particular, thanks to the Montessus de Ballore's theorem we are
able to unfold the Second Riemann sheet of an amplitude to search the position
of the resonant pole in the complex plane. The method is systematic and
provides a model-independent treatment of the prediction and the corresponding
errors of the approximation. This letter partially covers the material
presented by the author at the 15th International QCD Conference: QCD 10 (25th
anniversary), Montpellier, France, 28 Jun - 3 Jul 2010 and at the Quark
Confinement and the Hadron Spectrum IX, 30 August - 3 September 2010, Madrid,
Spain.
| [
{
"created": "Mon, 13 Dec 2010 17:21:06 GMT",
"version": "v1"
}
] | 2010-12-14 | [
[
"Masjuan",
"Pere",
""
]
] | Based on the mathematically well defined Pad\'e Theory, a theoretically safe new procedure for the extraction of the pole mass and width of resonances is proposed. In particular, thanks to the Montessus de Ballore's theorem we are able to unfold the Second Riemann sheet of an amplitude to search the position of the resonant pole in the complex plane. The method is systematic and provides a model-independent treatment of the prediction and the corresponding errors of the approximation. This letter partially covers the material presented by the author at the 15th International QCD Conference: QCD 10 (25th anniversary), Montpellier, France, 28 Jun - 3 Jul 2010 and at the Quark Confinement and the Hadron Spectrum IX, 30 August - 3 September 2010, Madrid, Spain. |
hep-ph/9707425 | Jisuke Kubo | Tatsuo Kobayashi, Jisuke Kubo, Myriam Mondragon, George Zoupanos | Constraints on Finite Soft Supersymmetry-Breaking Terms | 34 pages | Nucl.Phys. B511 (1998) 45-68 | 10.1016/S0550-3213(97)00765-7 | Kanazawa University Report, KANAZAWA-97-12 | hep-ph | null | Requiring the soft supersymmetry-breaking (SSB) parameters in finite
gauge-Yukawa unified models to be finite up to and including two-loop order, we
derive a two-loop sum rule for the soft scalar-masses. It is shown that this
sum rule coincides with that of a certain class of string models in which the
massive string states are organized into N=4 supermultiplets. We investigate
the SSB sector of two finite SU(5) models. Using the sum rule which allows the
non-universality of the SSB terms and requiring that the lightest superparticle
particleis neutral, we constrain the parameter space of the SSB sector in each
model.
| [
{
"created": "Tue, 22 Jul 1997 14:38:06 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Kobayashi",
"Tatsuo",
""
],
[
"Kubo",
"Jisuke",
""
],
[
"Mondragon",
"Myriam",
""
],
[
"Zoupanos",
"George",
""
]
] | Requiring the soft supersymmetry-breaking (SSB) parameters in finite gauge-Yukawa unified models to be finite up to and including two-loop order, we derive a two-loop sum rule for the soft scalar-masses. It is shown that this sum rule coincides with that of a certain class of string models in which the massive string states are organized into N=4 supermultiplets. We investigate the SSB sector of two finite SU(5) models. Using the sum rule which allows the non-universality of the SSB terms and requiring that the lightest superparticle particleis neutral, we constrain the parameter space of the SSB sector in each model. |
hep-ph/0408123 | Morimitsu Tanimoto | Walter Grimus, Anjan S.Joshipura, Satoru Kaneko, Lu\'is Lavoura,
Hideyuki Sawanaka, Morimitsu Tanimoto | Non-vanishing $U_{e3}$ and $\cos{2 \theta_{23}}$ from a broken $Z_2$
symmetry | 28 pages, 12 figures, Some discussions are revised, references are
corrected, Conclusions are unchanged | Nucl.Phys.B713:151-172,2005 | 10.1016/j.nuclphysb.2005.01.049 | UWThPh-2004-19, OCHA-PP-244 | hep-ph | null | It is shown that the neutrino mass matrices in the flavour basis yielding a
vanishing $U_{e3}$ are characterized by invariance under a class of $Z_2$
symmetries. A specific $Z_2$ in this class also leads to a maximal atmospheric
mixing angle $\theta_{23}$. The breaking of that $Z_2$ can be parameterized by
two dimensionless quantities, $\e$ and $\e'$; the effects of $\e, \e' \neq 0$
are studied perturbatively and numerically. The induced value of $\ue3$
strongly depends on the neutrino mass hierarchy. We find that $\ue3$ is less
than 0.07 for a normal mass hierarchy, even when $\e, \e' \sim 30 %$. For an
inverted mass hierarchy $\ue3$ tends to be around 0.1 but can be as large as
0.17. In the case of quasi-degenerate neutrinos, $\ue3$ could be close to its
experimental upper bound 0.2. In contrast, $| \cos{2\theta_{23}} |$ can always
reach its experimental upper bound 0.28. We propose a specific model, based on
electroweak radiative corrections in the MSSM, for $\e$ and $\e'$. In that
model, both $\ue3$ and $| \cos{2 \theta_{23}} |$, could be close to their
respective experimental upper bounds if neutrinos are quasi-degenerate.
| [
{
"created": "Tue, 10 Aug 2004 05:40:27 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Aug 2004 01:15:56 GMT",
"version": "v2"
},
{
"created": "Fri, 3 Dec 2004 09:34:24 GMT",
"version": "v3"
},
{
"created": "Wed, 19 Jan 2005 09:22:54 GMT",
"version": "v4"
}
] | 2016-08-16 | [
[
"Grimus",
"Walter",
""
],
[
"Joshipura",
"Anjan S.",
""
],
[
"Kaneko",
"Satoru",
""
],
[
"Lavoura",
"Luís",
""
],
[
"Sawanaka",
"Hideyuki",
""
],
[
"Tanimoto",
"Morimitsu",
""
]
] | It is shown that the neutrino mass matrices in the flavour basis yielding a vanishing $U_{e3}$ are characterized by invariance under a class of $Z_2$ symmetries. A specific $Z_2$ in this class also leads to a maximal atmospheric mixing angle $\theta_{23}$. The breaking of that $Z_2$ can be parameterized by two dimensionless quantities, $\e$ and $\e'$; the effects of $\e, \e' \neq 0$ are studied perturbatively and numerically. The induced value of $\ue3$ strongly depends on the neutrino mass hierarchy. We find that $\ue3$ is less than 0.07 for a normal mass hierarchy, even when $\e, \e' \sim 30 %$. For an inverted mass hierarchy $\ue3$ tends to be around 0.1 but can be as large as 0.17. In the case of quasi-degenerate neutrinos, $\ue3$ could be close to its experimental upper bound 0.2. In contrast, $| \cos{2\theta_{23}} |$ can always reach its experimental upper bound 0.28. We propose a specific model, based on electroweak radiative corrections in the MSSM, for $\e$ and $\e'$. In that model, both $\ue3$ and $| \cos{2 \theta_{23}} |$, could be close to their respective experimental upper bounds if neutrinos are quasi-degenerate. |
1706.07648 | Olga I. Piskounova | Olga I. Piskounova | Baryon Production at LHC Experiments: Average pt of Hyperons vs. Energy | 12 pages, 10 .eps figures, arXiv admin note: text overlap with
arXiv:1602.08003 | International Journal of Modern Physics A Vol. 35, No. 13 (2020)
2050067 (12 pages) | 10.1142/S0217-75X12(05)00670 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This paper examines the transverse momentum spectra of baryons in the
multi-particle production at modern colliders using Quark-Gluon String Model
(QGSM). It discusses 1) the difference in \Lambda^0 hyperon spectra at
antiproton-proton vs. proton-proton reactions; 2) the growth of average
transverse momenta of \Lambda hyperon with proton-proton collision energies and
3) the dependence of average p_t on the masses of mesons and baryons at the LHC
energy 7 TeV. This analysis of baryon spectra led to the following conclusions.
First, the fragmentation of antidiquark-diquark side of the pomeron diagram
makes the major contribution to baryon production spectra in the asymmetric
antiproton-proton reaction. Second, the average p_t's of hyperons steadily grow
with energy on the range from 53 GeV to 7 TeV. Since no dramatic changes were
seen in the characteristics of baryon production, the hadroproduction processes
do not cause the "knee" in the cosmic ray proton spectra at the energies
between Tevatron and LHC.
| [
{
"created": "Fri, 23 Jun 2017 11:49:41 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Apr 2020 13:26:19 GMT",
"version": "v10"
},
{
"created": "Tue, 2 Jun 2020 11:15:12 GMT",
"version": "v11"
},
{
"created": "Tue, 4 Jul 2017 10:25:10 GMT",
"version": "v2"
},
{
"cr... | 2020-06-03 | [
[
"Piskounova",
"Olga I.",
""
]
] | This paper examines the transverse momentum spectra of baryons in the multi-particle production at modern colliders using Quark-Gluon String Model (QGSM). It discusses 1) the difference in \Lambda^0 hyperon spectra at antiproton-proton vs. proton-proton reactions; 2) the growth of average transverse momenta of \Lambda hyperon with proton-proton collision energies and 3) the dependence of average p_t on the masses of mesons and baryons at the LHC energy 7 TeV. This analysis of baryon spectra led to the following conclusions. First, the fragmentation of antidiquark-diquark side of the pomeron diagram makes the major contribution to baryon production spectra in the asymmetric antiproton-proton reaction. Second, the average p_t's of hyperons steadily grow with energy on the range from 53 GeV to 7 TeV. Since no dramatic changes were seen in the characteristics of baryon production, the hadroproduction processes do not cause the "knee" in the cosmic ray proton spectra at the energies between Tevatron and LHC. |
hep-ph/0412049 | Cristian Pisano | M.Gl\"uck, C.Pisano, E. Reya | Probing the Perturbative NLO Parton Evolution in the Small-$x$ Region | Revised version, to appear in EPJC | Eur.Phys.J.C40:515-517,2005 | 10.1140/epjc/s2005-02167-3 | DO-TH 2004/13 | hep-ph hep-ex | null | A dedicated test of the perturbative QCD NLO parton evolution in the very
small-$x$ region is performed. We find a good agreement with recent precision
HERA-data for $F_2^p(x,Q^2)$, as well as with the present determination of the
curvature of $F_2^p$. Characteristically, perturbative QCD evolutions result in
a positive curvature which increases as $x$ decreases. Future precision
measurements in the very small $x$-region, $x<10^{-4}$, could provide a
sensitive test of the range of validity of perturbative QCD
| [
{
"created": "Fri, 3 Dec 2004 15:38:19 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Feb 2005 10:24:13 GMT",
"version": "v2"
}
] | 2009-04-15 | [
[
"Glück",
"M.",
""
],
[
"Pisano",
"C.",
""
],
[
"Reya",
"E.",
""
]
] | A dedicated test of the perturbative QCD NLO parton evolution in the very small-$x$ region is performed. We find a good agreement with recent precision HERA-data for $F_2^p(x,Q^2)$, as well as with the present determination of the curvature of $F_2^p$. Characteristically, perturbative QCD evolutions result in a positive curvature which increases as $x$ decreases. Future precision measurements in the very small $x$-region, $x<10^{-4}$, could provide a sensitive test of the range of validity of perturbative QCD |
hep-ph/0410122 | Sabine Hossenfelder | Sabine Hossenfelder | The Minimal Length and Large Extra Dimensions | 18 pages, 5 figures, brief review to appear in Mod. Phys. Let. A | Mod.Phys.Lett. A19 (2004) 2727-2744 | 10.1142/S0217732304015919 | null | hep-ph hep-th | null | Planck scale physics represents a future challenge, located between particle
physics and general relativity. The Planck scale marks a threshold beyond which
the old description of spacetime breaks down and conceptually new phenomena
must appear. Little is known about the fundamental theory valid at Planckian
energies, except that it necessarily seems to imply the occurrence of a minimal
length scale, providing a natural ultraviolet cutoff and a limit to the
possible resolution of spacetime.
Motivated by String Theory, the models of large extra dimensions lower the
Planck scale to values soon accessible. These models predict a vast number of
quantum gravity effects at the lowered Planck scale, among them the production
of TeV-mass black holes and gravitons. Within the extra dimensional scenario,
also the minimal length comes into the reach of experiment and sets a
fundamental limit to short distance physics.
We review the status of Planck scale physics in these effective models.
| [
{
"created": "Fri, 8 Oct 2004 00:49:41 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Hossenfelder",
"Sabine",
""
]
] | Planck scale physics represents a future challenge, located between particle physics and general relativity. The Planck scale marks a threshold beyond which the old description of spacetime breaks down and conceptually new phenomena must appear. Little is known about the fundamental theory valid at Planckian energies, except that it necessarily seems to imply the occurrence of a minimal length scale, providing a natural ultraviolet cutoff and a limit to the possible resolution of spacetime. Motivated by String Theory, the models of large extra dimensions lower the Planck scale to values soon accessible. These models predict a vast number of quantum gravity effects at the lowered Planck scale, among them the production of TeV-mass black holes and gravitons. Within the extra dimensional scenario, also the minimal length comes into the reach of experiment and sets a fundamental limit to short distance physics. We review the status of Planck scale physics in these effective models. |
2201.08577 | Tian-Xing Bai | Wei-Jie Xu, Tian-Xing Bai and Chun-Gui Duan | Atomic mass, Bjorken variable and scale dependence of quark transport
coefficient in Drell-Yan process for proton incident on nucleus | arXiv admin note: text overlap with arXiv:2012.03167 | Chin. Phys. C 47, (2023) | 10.1088/1674-1137/acb8a4 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | By means of the nuclear parton distributions determined without the
fixed-target Drell-Yan experimental data and the analytic expression of
quenching weight based on BDMPS formalism, a next-to-leading order analyses are
performed on the Drell-Yan differential cross section ratios from Fermilab E906
and E866 Collaborations. It is found that the calculated results with only the
nuclear effects of parton distribution are not in agreement with the E866 and
E906 experimental data. The incoming parton energy loss effect can not be
ignored in the nuclear Drell-Yan reactions. The predicted results indicate that
with the quark transport coefficient as a constant, the suppression due to the
target nuclear geometry effect is approximately 19.24% for the quark transport
coefficient. It is shown that we should consider the target nuclear geometry
effect in studying the Drell-Yan reaction on nuclear targets. On the basis of
Bjorken variable and scale dependence of the quark transport coefficient, the
atomic mass dependence is incorporated. The quark transport coefficient is
determined as a function of the atomic mass, Bjorken variable $x_2$ and scale
$Q^2$ by the global fit of the experimental data. The determined constant
factor $\hat{q}_0$ of the quark transport coefficient is $0.061\pm0.004 {\rm
GeV^2/fm}$. It is found that the atomic mass dependence has a remarkable impact
on the constant factor $\hat{q}_0$ in the quark transport coefficient in cold
nuclear matter.
| [
{
"created": "Fri, 21 Jan 2022 07:43:49 GMT",
"version": "v1"
}
] | 2023-02-10 | [
[
"Xu",
"Wei-Jie",
""
],
[
"Bai",
"Tian-Xing",
""
],
[
"Duan",
"Chun-Gui",
""
]
] | By means of the nuclear parton distributions determined without the fixed-target Drell-Yan experimental data and the analytic expression of quenching weight based on BDMPS formalism, a next-to-leading order analyses are performed on the Drell-Yan differential cross section ratios from Fermilab E906 and E866 Collaborations. It is found that the calculated results with only the nuclear effects of parton distribution are not in agreement with the E866 and E906 experimental data. The incoming parton energy loss effect can not be ignored in the nuclear Drell-Yan reactions. The predicted results indicate that with the quark transport coefficient as a constant, the suppression due to the target nuclear geometry effect is approximately 19.24% for the quark transport coefficient. It is shown that we should consider the target nuclear geometry effect in studying the Drell-Yan reaction on nuclear targets. On the basis of Bjorken variable and scale dependence of the quark transport coefficient, the atomic mass dependence is incorporated. The quark transport coefficient is determined as a function of the atomic mass, Bjorken variable $x_2$ and scale $Q^2$ by the global fit of the experimental data. The determined constant factor $\hat{q}_0$ of the quark transport coefficient is $0.061\pm0.004 {\rm GeV^2/fm}$. It is found that the atomic mass dependence has a remarkable impact on the constant factor $\hat{q}_0$ in the quark transport coefficient in cold nuclear matter. |
1312.0307 | Toshitaka Tatsumi | T. Tatsumi, K. Nishiyama and S. Karasawa | Inhomogeneous chiral phase in the magnetic field | 8 pages, 3 figures, Proc. of the 2nd International Conference on New
Frontiers in Physics (ICNFP 2013) | null | 10.1051/epjconf/20147100131 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inhomogeneous chiral phase is discussed in the presence of the magnetic
field. A topological aspect is pointed out for the complex order parameter, in
relation to the spectral asymmetry of the Dirac operator. It induces an
anomalous baryon number and extremely extends the region of the inhomogeneous
chiral phase in the QCD phase diagram. It is also shown that the novel
tricritical point appears at zero chemical potential, which should be examined
by the lattice QCD simulation.
| [
{
"created": "Mon, 2 Dec 2013 02:40:58 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Tatsumi",
"T.",
""
],
[
"Nishiyama",
"K.",
""
],
[
"Karasawa",
"S.",
""
]
] | Inhomogeneous chiral phase is discussed in the presence of the magnetic field. A topological aspect is pointed out for the complex order parameter, in relation to the spectral asymmetry of the Dirac operator. It induces an anomalous baryon number and extremely extends the region of the inhomogeneous chiral phase in the QCD phase diagram. It is also shown that the novel tricritical point appears at zero chemical potential, which should be examined by the lattice QCD simulation. |
1404.7139 | Andreas Papaefstathiou | Danilo Enoque Ferreira de Lima, Andreas Papaefstathiou, Michael
Spannowsky | Standard Model Higgs boson pair production in the $(b\bar{b})(b\bar{b})$
final state | 19 pages, 9 figures, matches published JHEP version | null | 10.1007/JHEP08(2014)030 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Measuring the Higgs boson couplings as precisely as possible is one of the
major goals of the High Luminosity LHC. We show that the $(b\bar{b})(b\bar{b})$
final state in Higgs boson pair production can be exploited in the boosted
regime to give constraints on the trilinear Higgs boson self-coupling. In these
exclusive phase space regions, novel jet substructure techniques can be used to
separate the signal from the large QCD and electroweak backgrounds. New
developments on trigger and b-tagging strategies for the upcoming LHC runs are
necessary in order to reconstruct the Higgs bosons in boosted final states,
where the trilinear self-coupling sensitivity is reduced. We find that using
our approach one can set a limit for $\lambda \leq 1.2$ at $95 \%$ CL after
$3000~\mathrm{fb}^{-1}$. As the signal-to-background ratio is small we propose
a data-driven side-band analysis to improve on the coupling measurement.
| [
{
"created": "Mon, 28 Apr 2014 20:00:19 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Aug 2014 15:28:34 GMT",
"version": "v2"
}
] | 2014-08-14 | [
[
"de Lima",
"Danilo Enoque Ferreira",
""
],
[
"Papaefstathiou",
"Andreas",
""
],
[
"Spannowsky",
"Michael",
""
]
] | Measuring the Higgs boson couplings as precisely as possible is one of the major goals of the High Luminosity LHC. We show that the $(b\bar{b})(b\bar{b})$ final state in Higgs boson pair production can be exploited in the boosted regime to give constraints on the trilinear Higgs boson self-coupling. In these exclusive phase space regions, novel jet substructure techniques can be used to separate the signal from the large QCD and electroweak backgrounds. New developments on trigger and b-tagging strategies for the upcoming LHC runs are necessary in order to reconstruct the Higgs bosons in boosted final states, where the trilinear self-coupling sensitivity is reduced. We find that using our approach one can set a limit for $\lambda \leq 1.2$ at $95 \%$ CL after $3000~\mathrm{fb}^{-1}$. As the signal-to-background ratio is small we propose a data-driven side-band analysis to improve on the coupling measurement. |
1911.10596 | Mikhail Vysotsky | M.A. Andreichikov, M.I. Eides, V.A. Novikov and M.I. Vysotsky | The physics of the $\eta$--$\eta'$ system versus $B^0 \rightarrow J/\Psi
\ \eta (\eta')$ and $B_s \rightarrow J/\Psi \ \eta (\eta')$ decays | 8 pages | null | 10.1142/S0217751X20501110 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An approach to the properties of the $\eta$--$\eta'$ system developed to
solve the famous $U(1)$ problem is used to calculate the partial widths ratios
to $\eta$ and $\eta'$ in the $B^0 \rightarrow J/\Psi \ \eta(\eta',\ \pi^0)$ and
$B_s \rightarrow J/\Psi \ \eta(\eta')$ decays. We obtain the results in
agreement with the experimental data.
| [
{
"created": "Sun, 24 Nov 2019 19:35:10 GMT",
"version": "v1"
}
] | 2020-08-26 | [
[
"Andreichikov",
"M. A.",
""
],
[
"Eides",
"M. I.",
""
],
[
"Novikov",
"V. A.",
""
],
[
"Vysotsky",
"M. I.",
""
]
] | An approach to the properties of the $\eta$--$\eta'$ system developed to solve the famous $U(1)$ problem is used to calculate the partial widths ratios to $\eta$ and $\eta'$ in the $B^0 \rightarrow J/\Psi \ \eta(\eta',\ \pi^0)$ and $B_s \rightarrow J/\Psi \ \eta(\eta')$ decays. We obtain the results in agreement with the experimental data. |
hep-ph/0401046 | Zhi-Gang Wang | Zhi-Gang Wang (CCAST, Ncepu), Wei-Min Yang (USTC) and Shao-Long Wan
(USTC) | Structures of the $f_0(980)$, $a_0(980)$ mesons and the strong coupling
constants $g_{f_0 K^+ K^-}$, $g_{a_0 K^+ K^-}$ with the light-cone QCD sum
rules | 14 pages; Revised version | Eur.Phys.J.C37:223-231,2004 | 10.1140/epjc/s2004-01992-0 | null | hep-ph | null | In this article, with the assumption of explicit isospin violation arising
from the $f_0(980)-a_0(980)$ mixing, we take the point of view that the scalar
mesons $f_0(980)$ and $a_0(980)$ have both strange and non-strange
quark-antiquark components and evaluate the strong coupling constants $g_{f_0
K^+ K^-}$ and $g_{a_0 K^+ K^-}$ within the framework of the light-cone QCD sum
rules approach. The large strong scalar-$KK$ couplings through both the
$n\bar{n}$ and $s\bar{s}$ components $g^{\bar{n}n}_{f_0 K^+ K^-}$,
$g^{\bar{s}s}_{f_0 K^+ K^-}$,
$g^{\bar{n}n}_{a_0 K^+ K^-}$ and $g^{\bar{s}s}_{a_0 K^+ K^-}$will support the
hadronic dressing mechanism, furthermore, in spite of the constituent structure
differences between the $f_0(980)$ and $a_0(980)$ mesons, the strange
components have larger strong coupling constants with the $K^+K^-$ state than
the corresponding non-strange ones, $g_{f_0 K^+ K^-}^{\bar{s}s}\approx
\sqrt{2}g_{f_0 K^+ K^-}^{\bar{n}n}$ and $g_{a_0 K^+ K^-}^{\bar{s}s}\approx
\sqrt{2} g_{a_0 K^+ K^-}^{\bar{n}n}$. From the existing controversial values,
we can not reach a general consensus on the strong coupling constants $g_{f_0
K^+ K^-}$, $g_{a_0 K^+ K^-}$ and the mixing angles.
| [
{
"created": "Fri, 9 Jan 2004 02:07:12 GMT",
"version": "v1"
},
{
"created": "Mon, 15 Mar 2004 02:11:28 GMT",
"version": "v2"
},
{
"created": "Sun, 25 Jul 2004 02:57:38 GMT",
"version": "v3"
}
] | 2016-09-06 | [
[
"Wang",
"Zhi-Gang",
"",
"CCAST, Ncepu"
],
[
"Yang",
"Wei-Min",
"",
"USTC"
],
[
"Wan",
"Shao-Long",
"",
"USTC"
]
] | In this article, with the assumption of explicit isospin violation arising from the $f_0(980)-a_0(980)$ mixing, we take the point of view that the scalar mesons $f_0(980)$ and $a_0(980)$ have both strange and non-strange quark-antiquark components and evaluate the strong coupling constants $g_{f_0 K^+ K^-}$ and $g_{a_0 K^+ K^-}$ within the framework of the light-cone QCD sum rules approach. The large strong scalar-$KK$ couplings through both the $n\bar{n}$ and $s\bar{s}$ components $g^{\bar{n}n}_{f_0 K^+ K^-}$, $g^{\bar{s}s}_{f_0 K^+ K^-}$, $g^{\bar{n}n}_{a_0 K^+ K^-}$ and $g^{\bar{s}s}_{a_0 K^+ K^-}$will support the hadronic dressing mechanism, furthermore, in spite of the constituent structure differences between the $f_0(980)$ and $a_0(980)$ mesons, the strange components have larger strong coupling constants with the $K^+K^-$ state than the corresponding non-strange ones, $g_{f_0 K^+ K^-}^{\bar{s}s}\approx \sqrt{2}g_{f_0 K^+ K^-}^{\bar{n}n}$ and $g_{a_0 K^+ K^-}^{\bar{s}s}\approx \sqrt{2} g_{a_0 K^+ K^-}^{\bar{n}n}$. From the existing controversial values, we can not reach a general consensus on the strong coupling constants $g_{f_0 K^+ K^-}$, $g_{a_0 K^+ K^-}$ and the mixing angles. |
2110.00286 | Tsuneo Uematsu | Ken Sasaki, Tsuneo Uematsu | Timelike Transition Form Factor for CP-odd Higgs Boson Production | 9 pages PDFLatex, SciPost.cls used, 6 figures (12 PDFs) and 1 jpeg
file, Contribution to the Proceedings of Radcor and LoopFest 2021 | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We investigate the production of CP-odd Higgs boson $A^0$ associated with a
real $\gamma$ in $e^+e^-$ collisions. Because of the properties of $A^0$
coupling to the other fields, the main contribution comes from the top-quark
triangle loop diagrams. We obtain the timelike transition form factor which
describes the production amplitude of $A^0$ in the $e^+e^-$ collisions. This
timelike transition form factor is related to the spacelike transition form
factor relevant for the $A^0$ production in $e^-\gamma$ collisions. It turns
out that the possible extra contributions from chargino-sneutrino and
neutralino-selectron box diagrams do not give sizable effects.
| [
{
"created": "Fri, 1 Oct 2021 09:47:39 GMT",
"version": "v1"
}
] | 2021-10-04 | [
[
"Sasaki",
"Ken",
""
],
[
"Uematsu",
"Tsuneo",
""
]
] | We investigate the production of CP-odd Higgs boson $A^0$ associated with a real $\gamma$ in $e^+e^-$ collisions. Because of the properties of $A^0$ coupling to the other fields, the main contribution comes from the top-quark triangle loop diagrams. We obtain the timelike transition form factor which describes the production amplitude of $A^0$ in the $e^+e^-$ collisions. This timelike transition form factor is related to the spacelike transition form factor relevant for the $A^0$ production in $e^-\gamma$ collisions. It turns out that the possible extra contributions from chargino-sneutrino and neutralino-selectron box diagrams do not give sizable effects. |
1708.09518 | Alexander Parada Dr. | B. C. Ca\~nas, E. A. Garc\'es, O. G. Miranda, and A. Parada | The reactor antineutrino anomaly and low energy threshold neutrino
experiments | 9 pages, 6 figures, 1 table, matches published version | null | 10.1016/j.physletb.2017.11.074 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Short distance reactor antineutrino experiments measure an antineutrino
spectrum a few percent lower than expected from theoretical predictions. In
this work we study the potential of low energy threshold reactor experiments in
the context of a light sterile neutrino signal. We discuss the perspectives of
the recently detected coherent elastic neutrino-nucleus scattering in future
reactor antineutrino experiments. We find that the expectations to improve the
current constraints on the mixing with sterile neutrinos are promising. We also
analyse the measurements of antineutrino scattering off electrons from short
distance reactor experiments. In this case, the statistics is not competitive
with inverse beta decay experiments, although future experiments might play a
role when compare it with the Gallium anomaly.
| [
{
"created": "Thu, 31 Aug 2017 01:08:41 GMT",
"version": "v1"
},
{
"created": "Sat, 17 Aug 2019 16:02:31 GMT",
"version": "v2"
}
] | 2019-08-20 | [
[
"Cañas",
"B. C.",
""
],
[
"Garcés",
"E. A.",
""
],
[
"Miranda",
"O. G.",
""
],
[
"Parada",
"A.",
""
]
] | Short distance reactor antineutrino experiments measure an antineutrino spectrum a few percent lower than expected from theoretical predictions. In this work we study the potential of low energy threshold reactor experiments in the context of a light sterile neutrino signal. We discuss the perspectives of the recently detected coherent elastic neutrino-nucleus scattering in future reactor antineutrino experiments. We find that the expectations to improve the current constraints on the mixing with sterile neutrinos are promising. We also analyse the measurements of antineutrino scattering off electrons from short distance reactor experiments. In this case, the statistics is not competitive with inverse beta decay experiments, although future experiments might play a role when compare it with the Gallium anomaly. |
1508.07923 | Sergey Alekhin | S. Alekhin, J. Bluemlein, S. Moch, R. Placakyte | Iso-spin asymmetry of quark distributions and implications for single
top-quark production at the LHC | 21 pages, 13 figures | Phys. Rev. D 94, 114038 (2016) | 10.1103/PhysRevD.94.114038 | DESY 15-161 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an improved determination of the up- and down-quark distributions
in the proton using recent data on charged lepton asymmetries from $W^\pm$
gauge-boson production at the LHC and Tevatron. The analysis is performed in
the framework of a global fit of parton distribution functions. The fit results
are consistent with a non-zero iso-spin asymmetry of the sea, $x(\bar d - \bar
u)$, at small values of Bjorken $x\sim 10^{-4}$ indicating a delayed onset of
the Regge asymptotics of a vanishing $(\bar d - \bar u)$-asymmetry at
small-$x$. We compare with up- and down-quark distributions available in the
literature and provide accurate predictions for the production of single
top-quarks at the LHC, a process which can serve as a standard candle for the
light quark flavor content of the proton.
| [
{
"created": "Mon, 31 Aug 2015 17:18:23 GMT",
"version": "v1"
}
] | 2017-01-04 | [
[
"Alekhin",
"S.",
""
],
[
"Bluemlein",
"J.",
""
],
[
"Moch",
"S.",
""
],
[
"Placakyte",
"R.",
""
]
] | We present an improved determination of the up- and down-quark distributions in the proton using recent data on charged lepton asymmetries from $W^\pm$ gauge-boson production at the LHC and Tevatron. The analysis is performed in the framework of a global fit of parton distribution functions. The fit results are consistent with a non-zero iso-spin asymmetry of the sea, $x(\bar d - \bar u)$, at small values of Bjorken $x\sim 10^{-4}$ indicating a delayed onset of the Regge asymptotics of a vanishing $(\bar d - \bar u)$-asymmetry at small-$x$. We compare with up- and down-quark distributions available in the literature and provide accurate predictions for the production of single top-quarks at the LHC, a process which can serve as a standard candle for the light quark flavor content of the proton. |
1308.0166 | Alfonso Zerwekh | Bastian Diaz and Alfonso R. Zerwekh | Axigluon Phenomenology using ATLAS dijet data | null | null | 10.1142/S0217751X13501339 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In recent years, there has been a renewed interest on axigluons as part of a
possible extension of strong interactions at high energies. In this work, we
use recent ATLAS measurements of the dijet spectrum in order to set limits on
the axigluon mass and coupling to quarks. We pay special attention to the
methodology used to extract the resonant contribution from theoretical
simulations. Finally, we present some predictions for the next LHC run at
$\sqrt{s}=14$ TeV.
| [
{
"created": "Thu, 1 Aug 2013 12:13:26 GMT",
"version": "v1"
}
] | 2015-06-16 | [
[
"Diaz",
"Bastian",
""
],
[
"Zerwekh",
"Alfonso R.",
""
]
] | In recent years, there has been a renewed interest on axigluons as part of a possible extension of strong interactions at high energies. In this work, we use recent ATLAS measurements of the dijet spectrum in order to set limits on the axigluon mass and coupling to quarks. We pay special attention to the methodology used to extract the resonant contribution from theoretical simulations. Finally, we present some predictions for the next LHC run at $\sqrt{s}=14$ TeV. |
hep-ph/0502150 | Yasaman Farzan | Y. Farzan, G. Gelmini and A. Kusenko | Pulsar Kicks from Majoron Emission | 4 pages, no figures | Phys.Lett.B621:22-27,2005 | 10.1016/j.physletb.2005.06.060 | UCLA/05/TEP/6 and IPM/P-2005/008 | hep-ph astro-ph | null | We show that Majoron emission from a hot nascent neutron star can be
anisotropic in the presence of a strong magnetic field. If Majorons carry a
non-negligible fraction of the supernova energy, the resulting recoil velocity
of a neutron star can explain the observed velocities of pulsars.
| [
{
"created": "Wed, 16 Feb 2005 14:47:29 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Farzan",
"Y.",
""
],
[
"Gelmini",
"G.",
""
],
[
"Kusenko",
"A.",
""
]
] | We show that Majoron emission from a hot nascent neutron star can be anisotropic in the presence of a strong magnetic field. If Majorons carry a non-negligible fraction of the supernova energy, the resulting recoil velocity of a neutron star can explain the observed velocities of pulsars. |
1910.06279 | Mikael Mieskolainen | Mikael Mieskolainen | Combinatorial Superstatistics for Soft QCD | 51 pages, 14 figures, v2 minor corrections | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | High energy diffraction and soft QCD span exciting final state topologies and
fluctuations which have not yet been measured or characterized in a fully
exhaustive way. In this work, we go beyond the standard measures and formulate
a new framework to generalize rapidity gap counting with emphasis on abstract
structure, fiducial observables, experimental limitations and factorizing model
dependence. The construction is based on a higher dimensional Bernoulli vector
statistics with a combinatorial incidence algebra structure, independent of the
underlying field theory. This is the first experimentally feasible framework
designed to probe the seemingly arcane sign alternating scattering amplitude
cutting rules of style Abramovski-Gribov-Kancheli, rules being of interest in
Regge theory, perturbative QCD and even in stringy black hole calculus. As an
additional novel show case, we pose, construct and solve a highly related
combinatorial stochastic superposition Poisson inverse problem using the
M\"obius inversion theorem.
| [
{
"created": "Mon, 14 Oct 2019 17:04:58 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Oct 2019 16:02:33 GMT",
"version": "v2"
}
] | 2019-10-16 | [
[
"Mieskolainen",
"Mikael",
""
]
] | High energy diffraction and soft QCD span exciting final state topologies and fluctuations which have not yet been measured or characterized in a fully exhaustive way. In this work, we go beyond the standard measures and formulate a new framework to generalize rapidity gap counting with emphasis on abstract structure, fiducial observables, experimental limitations and factorizing model dependence. The construction is based on a higher dimensional Bernoulli vector statistics with a combinatorial incidence algebra structure, independent of the underlying field theory. This is the first experimentally feasible framework designed to probe the seemingly arcane sign alternating scattering amplitude cutting rules of style Abramovski-Gribov-Kancheli, rules being of interest in Regge theory, perturbative QCD and even in stringy black hole calculus. As an additional novel show case, we pose, construct and solve a highly related combinatorial stochastic superposition Poisson inverse problem using the M\"obius inversion theorem. |
1707.08366 | Rafal Maciula | Rafal Maciula and Antoni Szczurek | Double-parton scattering effects in associated production of charm
mesons and dijets at the LHC | 18 pages, 11 figures | Phys. Rev. D 96, 074013 (2017) | 10.1103/PhysRevD.96.074013 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate several differential distributions for the production of charm
and dijets. Both single-parton scattering (SPS) and double-parton scattering
(DPS) contributions are calculated in the $k_T$-factorization approach. The
Kimber-Martin-Ryskin unintegrated parton distributions are used in our
calculations. Relatively low cuts on jet transverse momenta are imposed to
enhance the double-parton scattering mechanism contribution. We find dominance
of the DPS contribution over the SPS one. We have found regions of the phase
space where the SPS contribution is negligible compared to the DPS
contribution. The distribution in transverse momentum of charm quark/antiquark
or charmed mesons can be used to observe transition from the dominance of DPS
at low transvsverse momenta to the dominance of SPS at large transverse
momenta. Very distinct azimuthal correlation patterns (for $c \bar{c}$,
$c\mathrm{\textit{-jet}}$, $\mathrm{\textit{jet-jet}}$,
$D^0\mathrm{\textit{-jet}}$, $D^0 D^0$) are predicted as a result of the
competition of the SPS and DPS mechanisms.
| [
{
"created": "Wed, 26 Jul 2017 10:45:11 GMT",
"version": "v1"
}
] | 2017-10-25 | [
[
"Maciula",
"Rafal",
""
],
[
"Szczurek",
"Antoni",
""
]
] | We calculate several differential distributions for the production of charm and dijets. Both single-parton scattering (SPS) and double-parton scattering (DPS) contributions are calculated in the $k_T$-factorization approach. The Kimber-Martin-Ryskin unintegrated parton distributions are used in our calculations. Relatively low cuts on jet transverse momenta are imposed to enhance the double-parton scattering mechanism contribution. We find dominance of the DPS contribution over the SPS one. We have found regions of the phase space where the SPS contribution is negligible compared to the DPS contribution. The distribution in transverse momentum of charm quark/antiquark or charmed mesons can be used to observe transition from the dominance of DPS at low transvsverse momenta to the dominance of SPS at large transverse momenta. Very distinct azimuthal correlation patterns (for $c \bar{c}$, $c\mathrm{\textit{-jet}}$, $\mathrm{\textit{jet-jet}}$, $D^0\mathrm{\textit{-jet}}$, $D^0 D^0$) are predicted as a result of the competition of the SPS and DPS mechanisms. |
2304.13665 | Bing-Long Zhang | Jian Tang, Bing-Long Zhang | Asymptotic Analysis on Binned Likelihood and Neutrino Floor | 29 pages, 8 figures, github repository:
https://github.com/zhangblong/AsymptoticAnalysisAndNeutrinoFog | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Observations of suspected coherent elastic neutrino-nucleus scatterings by
dark matter direct detection experiments highlight the need for an
investigation into the so-called "neutrino floor". We focus on the discovery
limit, a statistical concept to identify the neutrino floor, and analyze the
asymptotic behaviour of the profile binned likelihood ratio test statistic
where the likelihood is constructed by variate from events in each bin and pull
terms from neutrino fluxes. To achieve the asymptotic result, we propose two
novel methods: i) Asymptotic-Analytic method, which furnishes the analytic
result for large statistics, is applicable for more extra nuisance parameters,
and enables the identification of the most relevant parameters in the
statistical analysis; ii) Quasi-Asimov dataset, which is analogous to Asimov
dataset but with improved speed. Applying our methods to the neutrino floor, we
significantly accelerate the computation procedure compared to the previous
literature, and successfully address cases where Asimov dataset fails. Our
derivation on the asymptotic behavior of the test statistic not only
facilitates research into the impact of neutrinos on the search for dark
matter, but may also prove relevant in similar application scenarios.
| [
{
"created": "Wed, 26 Apr 2023 16:39:32 GMT",
"version": "v1"
},
{
"created": "Wed, 10 May 2023 07:35:24 GMT",
"version": "v2"
},
{
"created": "Tue, 8 Aug 2023 01:50:14 GMT",
"version": "v3"
}
] | 2023-08-09 | [
[
"Tang",
"Jian",
""
],
[
"Zhang",
"Bing-Long",
""
]
] | Observations of suspected coherent elastic neutrino-nucleus scatterings by dark matter direct detection experiments highlight the need for an investigation into the so-called "neutrino floor". We focus on the discovery limit, a statistical concept to identify the neutrino floor, and analyze the asymptotic behaviour of the profile binned likelihood ratio test statistic where the likelihood is constructed by variate from events in each bin and pull terms from neutrino fluxes. To achieve the asymptotic result, we propose two novel methods: i) Asymptotic-Analytic method, which furnishes the analytic result for large statistics, is applicable for more extra nuisance parameters, and enables the identification of the most relevant parameters in the statistical analysis; ii) Quasi-Asimov dataset, which is analogous to Asimov dataset but with improved speed. Applying our methods to the neutrino floor, we significantly accelerate the computation procedure compared to the previous literature, and successfully address cases where Asimov dataset fails. Our derivation on the asymptotic behavior of the test statistic not only facilitates research into the impact of neutrinos on the search for dark matter, but may also prove relevant in similar application scenarios. |
1305.2407 | Magno Machado | M.B. Gay Ducati, M.T. Griep, M.V.T. Machado | Diffractive photoproduction of radially excited psi(2S) mesons in
photon-Pomeron reactions in PbPb collisions at the CERN LHC | 06 pages, 3 figures. Version to be published in Physical Review C | Phys. Rev. C 88, 014910 (2013) | 10.1103/PhysRevC.88.014910 | null | hep-ph hep-ex nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we investigate the photoproduction of radially excited vector
mesons off nuclei in heavy ion relativistic collisions. In particular, we
analyze the exclusive photoproduction of psi(2S) off nuclei, evaluating the
coherent and the incoherent contributions to that process. The theoretical
framework used in the present analysis is the light-cone dipole formalism and
predictions are done for PbPb collisions at the CERN-LHC energy of 2.76 TeV.
The theoretical uncertainties are analyzed and comparison is also done to the
recent ALICE Collaboration data for the psi(1S) state photoproduction.
| [
{
"created": "Fri, 10 May 2013 19:29:03 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Jul 2013 19:04:29 GMT",
"version": "v2"
},
{
"created": "Wed, 18 Jun 2014 16:40:38 GMT",
"version": "v3"
}
] | 2014-06-19 | [
[
"Ducati",
"M. B. Gay",
""
],
[
"Griep",
"M. T.",
""
],
[
"Machado",
"M. V. T.",
""
]
] | In this work we investigate the photoproduction of radially excited vector mesons off nuclei in heavy ion relativistic collisions. In particular, we analyze the exclusive photoproduction of psi(2S) off nuclei, evaluating the coherent and the incoherent contributions to that process. The theoretical framework used in the present analysis is the light-cone dipole formalism and predictions are done for PbPb collisions at the CERN-LHC energy of 2.76 TeV. The theoretical uncertainties are analyzed and comparison is also done to the recent ALICE Collaboration data for the psi(1S) state photoproduction. |
2301.07571 | Baisakhi Mitra | B. Mitra | Search for CPT and Lorentz Invariance Violation in the Muon g-2
Experiment at Fermilab | Presented at the Ninth Meeting on CPT and Lorentz Symmetry,
Bloomington, Indiana, May 17-26, 2022 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Muon g-2 data can be used to study sidereal variation of anomalous muon
precession rate, which is one of the important signatures of CPT and Lorentz
invariance violation. The discussion in this proceeding will focus on the
framework which has been used to study sidereal variation of anomalous muon
precession rate in Muon g-2 Run 2 data. Also, a brief introduction will be
given about the blinding framework which will be used on Run 2/3 data of Muon
g-2 experiment. This blinding framework will keep the actual result of the
experiment masked from the analyzer during the analysis process.
| [
{
"created": "Tue, 17 Jan 2023 17:06:25 GMT",
"version": "v1"
},
{
"created": "Sat, 21 Jan 2023 00:26:47 GMT",
"version": "v2"
}
] | 2023-01-24 | [
[
"Mitra",
"B.",
""
]
] | Muon g-2 data can be used to study sidereal variation of anomalous muon precession rate, which is one of the important signatures of CPT and Lorentz invariance violation. The discussion in this proceeding will focus on the framework which has been used to study sidereal variation of anomalous muon precession rate in Muon g-2 Run 2 data. Also, a brief introduction will be given about the blinding framework which will be used on Run 2/3 data of Muon g-2 experiment. This blinding framework will keep the actual result of the experiment masked from the analyzer during the analysis process. |
1204.1735 | Robert Fleischer | Kristof De Bruyn, Robert Fleischer, Robert Knegjens, Patrick
Koppenburg, Marcel Merk, Niels Tuning | Branching Ratio Measurements of $B_s$ Decays | 7 pages, 1 figure, title matches published version in Physical Review
D | Phys. Rev. D 86, 014027 (2012) | 10.1103/PhysRevD.86.014027 | Nikhef-2012-005 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have just entered an era of precision measurements for $B_s$-decay
observables. A characteristic feature of the $B_s$-meson system is
$B^0_s$--$\bar B^0_s$ mixing, which exhibits a sizable decay width difference.
The latter feature leads to a subtle complication for the extraction of
branching ratios of $B_s$ decays from untagged data samples, leading to
systematic biases as large as O(10%) that depend on the dynamics of the
considered decay. We point out that this effect can only be corrected for using
information from a time-dependent analysis and suggest the use of the effective
$B_s$ decay lifetime, which can already be extracted from the untagged data
sample, for this purpose. We also address several experimental issues that can
play a role in the extraction of effective lifetimes at a hadron collider, and
advocate the use of the $B_s$ branching ratios, as presented in this note, for
consistent comparisons of theoretical calculations and experimental
measurements in particle listings.
| [
{
"created": "Sun, 8 Apr 2012 15:10:01 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Apr 2012 16:21:44 GMT",
"version": "v2"
},
{
"created": "Thu, 12 Jul 2012 15:04:12 GMT",
"version": "v3"
},
{
"created": "Fri, 27 Jul 2012 09:00:12 GMT",
"version": "v4"
}
] | 2012-07-30 | [
[
"De Bruyn",
"Kristof",
""
],
[
"Fleischer",
"Robert",
""
],
[
"Knegjens",
"Robert",
""
],
[
"Koppenburg",
"Patrick",
""
],
[
"Merk",
"Marcel",
""
],
[
"Tuning",
"Niels",
""
]
] | We have just entered an era of precision measurements for $B_s$-decay observables. A characteristic feature of the $B_s$-meson system is $B^0_s$--$\bar B^0_s$ mixing, which exhibits a sizable decay width difference. The latter feature leads to a subtle complication for the extraction of branching ratios of $B_s$ decays from untagged data samples, leading to systematic biases as large as O(10%) that depend on the dynamics of the considered decay. We point out that this effect can only be corrected for using information from a time-dependent analysis and suggest the use of the effective $B_s$ decay lifetime, which can already be extracted from the untagged data sample, for this purpose. We also address several experimental issues that can play a role in the extraction of effective lifetimes at a hadron collider, and advocate the use of the $B_s$ branching ratios, as presented in this note, for consistent comparisons of theoretical calculations and experimental measurements in particle listings. |
0901.4175 | Seung-il Nam | Seung-il Nam, Daisuke Jido | Lambda(1405) photoprodcution with p-wave contributions | 10 pages, 7 figures, Talk given at the Workshop "Strangeness in
Multi-Quark Systems", 29 ~ 31 Oct 2008, Kaga, Japan | null | null | YITP-09-03 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this report, we present our recent studies on the
Lambda(1405,1/2-)=Lambda* photoproduction via the gamma p -> K+ pi Sigma
scattering process, employing a coupled-channel formalism, i.e., the chiral
unitary model, which respects chiral dynamics in terms of the Weinberg-Tomozawa
meson baryon interaction. In addition to the dynamically generated s-wave
resonance, Lambda*, we include the p-wave resonance contribution from
Sigma(1385,3/2+). We observe that the p-wave contribution provides considerable
effects on the pi-Sigma invariant-mass spectrum. It also turns out that, within
the present level of calculations, we can reproduce hardly the recent Lambda*
photoproduction experiment by LEPS collaboration at SPring-8.
| [
{
"created": "Tue, 27 Jan 2009 04:57:20 GMT",
"version": "v1"
}
] | 2009-01-28 | [
[
"Nam",
"Seung-il",
""
],
[
"Jido",
"Daisuke",
""
]
] | In this report, we present our recent studies on the Lambda(1405,1/2-)=Lambda* photoproduction via the gamma p -> K+ pi Sigma scattering process, employing a coupled-channel formalism, i.e., the chiral unitary model, which respects chiral dynamics in terms of the Weinberg-Tomozawa meson baryon interaction. In addition to the dynamically generated s-wave resonance, Lambda*, we include the p-wave resonance contribution from Sigma(1385,3/2+). We observe that the p-wave contribution provides considerable effects on the pi-Sigma invariant-mass spectrum. It also turns out that, within the present level of calculations, we can reproduce hardly the recent Lambda* photoproduction experiment by LEPS collaboration at SPring-8. |
2007.03939 | Amaresh Jaiswal | Partha Pratim Bhaduri, Mubarak Alqahtani, Nicolas Borghini, Amaresh
Jaiswal, Michael Strickland | Fireball tomography from bottomonia elliptic flow in relativistic
heavy-ion collisions | 8 pages, 5 figures, ancillary files with data of the figures are
included in the source | Eur. Phys. J. C 81, 585 (2021) | 10.1140/epjc/s10052-021-09383-3 | null | hep-ph hep-ex hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the elliptic flow of bottomonia produced in Pb$\,+\,$Pb
collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. We consider temperature-dependent
decay widths for the anisotropic escape of various bottomonium states and
observe that the transverse momentum dependence of bottomonia elliptic flow
provides a tomographic information about the QGP fireball at different stages
of its evolution. For the space-time evolution of the fireball, we employ
simulation results from the 3+1D quasiparticle anisotropic hydrodynamic model.
We find that our results for transverse momentum dependence of bottomonia
elliptic flow are in reasonable agreement with experimental results from the
ALICE and CMS collaborations.
| [
{
"created": "Wed, 8 Jul 2020 07:45:01 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Jul 2021 10:03:00 GMT",
"version": "v2"
}
] | 2021-07-09 | [
[
"Bhaduri",
"Partha Pratim",
""
],
[
"Alqahtani",
"Mubarak",
""
],
[
"Borghini",
"Nicolas",
""
],
[
"Jaiswal",
"Amaresh",
""
],
[
"Strickland",
"Michael",
""
]
] | We calculate the elliptic flow of bottomonia produced in Pb$\,+\,$Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. We consider temperature-dependent decay widths for the anisotropic escape of various bottomonium states and observe that the transverse momentum dependence of bottomonia elliptic flow provides a tomographic information about the QGP fireball at different stages of its evolution. For the space-time evolution of the fireball, we employ simulation results from the 3+1D quasiparticle anisotropic hydrodynamic model. We find that our results for transverse momentum dependence of bottomonia elliptic flow are in reasonable agreement with experimental results from the ALICE and CMS collaborations. |
hep-ph/0006311 | Stephen Parke | J. Goldstein, C.S. Hill, J. Incandela, Stephen Parke, D. Rainwater and
D. Stuart | P Pbar to T Tbar H: A Discovery mode for the Higgs boson at the Tevatron | 10 pages, Latex, RevTex, 3 ps figures: Updated reconstruction
efficiency and figures | Phys.Rev.Lett.86:1694-1697,2001 | 10.1103/PhysRevLett.86.1694 | FERMILAB-Pub-00/146-T | hep-ph hep-ex | null | The production of a Standard Model Higgs boson in association with a top
quark pair at the upcoming high luminosity run (15 inverse fb integrated
luminosity) of the Fermilab Tevatron (root s = 2.0 TeV) is revisited. For Higgs
masses below 140 GeV we demonstrate that the production cross section times
branching ratio for H->B Bbar decays yields a significant number of events and
that this mode is competitive with and complementary to the searches using P
Pbar -> WH, ZH associated production. For higher mass Higgs bosons the H -> W+
W- decays are more difficult but have the potential to provide a few
spectacular events.
| [
{
"created": "Tue, 27 Jun 2000 21:15:07 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Jan 2001 23:21:03 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Goldstein",
"J.",
""
],
[
"Hill",
"C. S.",
""
],
[
"Incandela",
"J.",
""
],
[
"Parke",
"Stephen",
""
],
[
"Rainwater",
"D.",
""
],
[
"Stuart",
"D.",
""
]
] | The production of a Standard Model Higgs boson in association with a top quark pair at the upcoming high luminosity run (15 inverse fb integrated luminosity) of the Fermilab Tevatron (root s = 2.0 TeV) is revisited. For Higgs masses below 140 GeV we demonstrate that the production cross section times branching ratio for H->B Bbar decays yields a significant number of events and that this mode is competitive with and complementary to the searches using P Pbar -> WH, ZH associated production. For higher mass Higgs bosons the H -> W+ W- decays are more difficult but have the potential to provide a few spectacular events. |
hep-ph/0008108 | Sven-Olaf Moch | T.O. Eynck, S. Moch (NIKHEF, Amsterdam) | Soft Gluon Resummation for Polarized Deep-inelastic Production of Heavy
Quarks | 11 pages, 5 figures, latex, minor changes | Phys.Lett. B495 (2000) 87-97 | 10.1016/S0370-2693(00)01211-9 | NIKHEF 00-022 | hep-ph | null | We present the threshold resummation for the cross section of heavy quark
production in polarized deep-inelastic scattering to next-to-leading
logarithmic accuracy and in single-particle inclusive kinematics. We expand our
resummed result in alpha_s to next-to-leading and next-to-next-to-leading order
and study the impact of these higher order corrections on the charm structure
function g_1 in the kinematical range accessible to the HERMES and COMPASS
experiments.
| [
{
"created": "Fri, 11 Aug 2000 11:55:28 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Oct 2000 14:31:49 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Eynck",
"T. O.",
"",
"NIKHEF, Amsterdam"
],
[
"Moch",
"S.",
"",
"NIKHEF, Amsterdam"
]
] | We present the threshold resummation for the cross section of heavy quark production in polarized deep-inelastic scattering to next-to-leading logarithmic accuracy and in single-particle inclusive kinematics. We expand our resummed result in alpha_s to next-to-leading and next-to-next-to-leading order and study the impact of these higher order corrections on the charm structure function g_1 in the kinematical range accessible to the HERMES and COMPASS experiments. |
hep-ph/0201020 | Pedro Vieira Alberto | M. Fiolhais, P. Alberto, J. Marques and B. Golli | Roper Electroproduction Amplitudes in a Chiral Confinement Model | 10 pages, 8 figures, uses World Scientific macros. Talk presented at
EMI2001 in Osaka, Japan | null | 10.1142/9789812777218_0025 | null | hep-ph | null | A description of the Roper using the chiral chromodielectric model is
presented and the transverse $A_{1/2}$ and the scalar $S_{1/2}$ helicity
amplitudes for the electromagnetic Nucleon--Roper transition are obtained for
small and moderate $Q^2$. The sign of the amplitudes is correct but the model
predictions underestimate the data at the photon point. Our results do not
indicate a change of sign in any amplitudes up to $Q^2\sim1$ GeV$^2$. The
contribution of the scalar meson excitations to the Roper electroproduction is
taken into account but it turns out to be small in comparison with the quark
contribution. However, it is argued that mesonic excitations may play a more
prominent role in higher excited states.
| [
{
"created": "Fri, 4 Jan 2002 19:42:51 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Fiolhais",
"M.",
""
],
[
"Alberto",
"P.",
""
],
[
"Marques",
"J.",
""
],
[
"Golli",
"B.",
""
]
] | A description of the Roper using the chiral chromodielectric model is presented and the transverse $A_{1/2}$ and the scalar $S_{1/2}$ helicity amplitudes for the electromagnetic Nucleon--Roper transition are obtained for small and moderate $Q^2$. The sign of the amplitudes is correct but the model predictions underestimate the data at the photon point. Our results do not indicate a change of sign in any amplitudes up to $Q^2\sim1$ GeV$^2$. The contribution of the scalar meson excitations to the Roper electroproduction is taken into account but it turns out to be small in comparison with the quark contribution. However, it is argued that mesonic excitations may play a more prominent role in higher excited states. |
1609.03309 | A. Tureanu | Kazuo Fujikawa and Anca Tureanu | Naturalness in see-saw mechanism and Bogoliubov transformation | 14 pages; version published in Phys. Lett. B | Phys.Lett. B767 (2017) 199-204 | 10.1016/j.physletb.2017.01.069 | null | hep-ph cond-mat.str-el cond-mat.supr-con hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an alternative perspective on the see-saw mechanism for the
neutrino mass, according to which the small neutrino mass is given as a
difference of two large masses. This view emerges when an analogue of the
Bogoliubov transformation is used to describe Majorana neutrinos in the
Lagrangian of the see-saw mechanism, which is analogous to the BCS theory. The
Bogoliubov transformation clarifies the natural appearance of Majorana fermions
when C is strongly violated by the right-handed neutrino mass term with good CP
in the single flavor model. Analyzing typical models with $m_{R}$= $10^{4}$ to
$10^{15}$ GeV, it is shown that a hitherto unrecognized fine tuning of the
order $m_{\nu}/m_{R}=10^{-15}$ to $10^{-26}$ is required to make the commonly
perceived see-saw mechanism work in a natural setting, namely, when none of
dimensionless coupling constants are very small.
| [
{
"created": "Mon, 12 Sep 2016 08:46:37 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Jan 2017 11:50:47 GMT",
"version": "v2"
},
{
"created": "Fri, 4 Aug 2017 20:12:54 GMT",
"version": "v3"
}
] | 2017-08-08 | [
[
"Fujikawa",
"Kazuo",
""
],
[
"Tureanu",
"Anca",
""
]
] | We present an alternative perspective on the see-saw mechanism for the neutrino mass, according to which the small neutrino mass is given as a difference of two large masses. This view emerges when an analogue of the Bogoliubov transformation is used to describe Majorana neutrinos in the Lagrangian of the see-saw mechanism, which is analogous to the BCS theory. The Bogoliubov transformation clarifies the natural appearance of Majorana fermions when C is strongly violated by the right-handed neutrino mass term with good CP in the single flavor model. Analyzing typical models with $m_{R}$= $10^{4}$ to $10^{15}$ GeV, it is shown that a hitherto unrecognized fine tuning of the order $m_{\nu}/m_{R}=10^{-15}$ to $10^{-26}$ is required to make the commonly perceived see-saw mechanism work in a natural setting, namely, when none of dimensionless coupling constants are very small. |
2310.12023 | Kunio Kaneta | Shinya Kanemura and Kunio Kaneta | Gravitational Waves from Particle Decays during Reheating | 7 pages, 2 figures, error fixed, new model added | null | null | OU--HET--1206 | hep-ph astro-ph.CO gr-qc | http://creativecommons.org/licenses/by/4.0/ | Gravitational waves have become an irreplaceable tool for exploring the
post-inflationary universe. Their cosmological and astrophysical origins have
been attracting numerous attention. In this Letter, we point out a novel source
of ultra-high frequency gravitational waves: the decay of particles produced
during the reheating era. We highlight the decay of the Higgs boson as a
representative case, showing how it yields a testable gravitational wave
spectrum by future observations.
| [
{
"created": "Wed, 18 Oct 2023 14:57:19 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Mar 2024 05:09:53 GMT",
"version": "v2"
}
] | 2024-03-19 | [
[
"Kanemura",
"Shinya",
""
],
[
"Kaneta",
"Kunio",
""
]
] | Gravitational waves have become an irreplaceable tool for exploring the post-inflationary universe. Their cosmological and astrophysical origins have been attracting numerous attention. In this Letter, we point out a novel source of ultra-high frequency gravitational waves: the decay of particles produced during the reheating era. We highlight the decay of the Higgs boson as a representative case, showing how it yields a testable gravitational wave spectrum by future observations. |
2008.06494 | Fabian Lange | Jonas Klappert, Fabian Lange, Philipp Maierh\"ofer, and Johann
Usovitsch | Integral Reduction with Kira 2.0 and Finite Field Methods | 32 pages, v2: minor changes and clarifications, matches published
version except for another fixed typo in Eq. (7) | Comput. Phys. Commun. 266 (2021) 108024 | 10.1016/j.cpc.2021.108024 | TTK-20-24, P3H-20-041, FR-PHENO-2020-11, MITP/20-044 | hep-ph hep-th | http://creativecommons.org/licenses/by/4.0/ | We present the new version 2.0 of the Feynman integral reduction program Kira
and describe the new features. The primary new feature is the reconstruction of
the final coefficients in integration-by-parts reductions by means of finite
field methods with the help of FireFly. This procedure can be parallelized on
computer clusters with MPI. Furthermore, the support for user-provided systems
of equations has been significantly improved. This mode provides the
flexibility to integrate Kira into projects that employ specialized reduction
formulas, direct reduction of amplitudes, or to problems involving linear
system of equations not limited to relations among standard Feynman integrals.
We show examples from state-of-the-art Feynman integral reduction problems and
provide benchmarks of the new features, demonstrating significantly reduced
main memory usage and improved performance w.r.t. previous versions of Kira.
| [
{
"created": "Fri, 14 Aug 2020 17:58:33 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Feb 2023 22:51:09 GMT",
"version": "v2"
}
] | 2023-02-24 | [
[
"Klappert",
"Jonas",
""
],
[
"Lange",
"Fabian",
""
],
[
"Maierhöfer",
"Philipp",
""
],
[
"Usovitsch",
"Johann",
""
]
] | We present the new version 2.0 of the Feynman integral reduction program Kira and describe the new features. The primary new feature is the reconstruction of the final coefficients in integration-by-parts reductions by means of finite field methods with the help of FireFly. This procedure can be parallelized on computer clusters with MPI. Furthermore, the support for user-provided systems of equations has been significantly improved. This mode provides the flexibility to integrate Kira into projects that employ specialized reduction formulas, direct reduction of amplitudes, or to problems involving linear system of equations not limited to relations among standard Feynman integrals. We show examples from state-of-the-art Feynman integral reduction problems and provide benchmarks of the new features, demonstrating significantly reduced main memory usage and improved performance w.r.t. previous versions of Kira. |
hep-ph/0610099 | Nicolas Matagne SE | N. Matagne, Fl. Stancu | New look at the $[{\bf 70},1^-]$ baryon multiplet in the $1/N_c$
expansion | 12 pages, 7 tables, to be published in Nuclear Physics A | Nucl.Phys.A811:291-305,2008 | 10.1016/j.nuclphysa.2008.07.006 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | So far, the masses of excited states of mixed orbital symmetry and in
particular those of nonstrange $[{\bf 70},1^-]$ baryons derived in the $1/N_c$
expansion were based on the separation of a system of $N_c$ quarks into a
symmetric core and an excited quark. Here we avoid this separation and show
that an advantage of this new approach is to substantially reduce the number of
linearly independent operators entering the mass formula. A novelty is that the
isospin-isospin term becomes as dominant in $\Delta$ as the spin-spin term in
$N$ resonances.
| [
{
"created": "Mon, 9 Oct 2006 14:59:20 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Nov 2006 14:06:34 GMT",
"version": "v2"
},
{
"created": "Thu, 4 Jan 2007 16:31:03 GMT",
"version": "v3"
},
{
"created": "Wed, 16 Jul 2008 14:59:48 GMT",
"version": "v4"
}
] | 2008-11-26 | [
[
"Matagne",
"N.",
""
],
[
"Stancu",
"Fl.",
""
]
] | So far, the masses of excited states of mixed orbital symmetry and in particular those of nonstrange $[{\bf 70},1^-]$ baryons derived in the $1/N_c$ expansion were based on the separation of a system of $N_c$ quarks into a symmetric core and an excited quark. Here we avoid this separation and show that an advantage of this new approach is to substantially reduce the number of linearly independent operators entering the mass formula. A novelty is that the isospin-isospin term becomes as dominant in $\Delta$ as the spin-spin term in $N$ resonances. |
hep-ph/0102150 | Zhang Zhao-xi | Chao-Hsi Chang, Yu-Qi Chen, Guo-Li Wang and Hong-Shi Zong | Semileptonic Decays of $B_c$ Meson to a P-Wave Charmonium State $\chi_c$
or $h_c$ | 8 pages, 2 figures | Commun.Theor.Phys.35:395-398,2001 | 10.1088/0253-6102/35/4/395 | null | hep-ph | null | The semileptonic decays of meson $B_c$ to a P-wave charmonium state
$\chi_c(^3P_J)$ or $h_c(^1P_1)$ are computed. The results show that the decays
are sizable so they are accessible in Tevatron and in LHC, especially, with the
detectors LHCB and BTeV in the foreseeable future, and of them, the one to the
$^1P_1$ charmonium state potentially offers us a novel window to see the
unconfirmed $h_c$ particle. In addition, it is pointed out that since the two
charmonium radiative decays $\chi_c(^3P_{1,2}) \to J/\psi+\gamma$ have sizable
branching ratios, the cascade decays of the concerned decays and the charmonium
radiative decays may affect the result of the observing the $B_c$ meson through
the semileptonic decays $B_{c}\to {J/\psi}+{l}+\nu_{l}$ substantially.
| [
{
"created": "Tue, 13 Feb 2001 12:19:59 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Feb 2001 03:48:45 GMT",
"version": "v2"
}
] | 2018-01-17 | [
[
"Chang",
"Chao-Hsi",
""
],
[
"Chen",
"Yu-Qi",
""
],
[
"Wang",
"Guo-Li",
""
],
[
"Zong",
"Hong-Shi",
""
]
] | The semileptonic decays of meson $B_c$ to a P-wave charmonium state $\chi_c(^3P_J)$ or $h_c(^1P_1)$ are computed. The results show that the decays are sizable so they are accessible in Tevatron and in LHC, especially, with the detectors LHCB and BTeV in the foreseeable future, and of them, the one to the $^1P_1$ charmonium state potentially offers us a novel window to see the unconfirmed $h_c$ particle. In addition, it is pointed out that since the two charmonium radiative decays $\chi_c(^3P_{1,2}) \to J/\psi+\gamma$ have sizable branching ratios, the cascade decays of the concerned decays and the charmonium radiative decays may affect the result of the observing the $B_c$ meson through the semileptonic decays $B_{c}\to {J/\psi}+{l}+\nu_{l}$ substantially. |
2111.02091 | C. Q. Geng | Chia-Wei Liu and Chao-Qiang Geng | Sizable Time-reversal violating effects in bottom baryon decays | 15 pages, 2 figures, revised version accepted by JHEP | null | 10.1007/JHEP01(2022)128 | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We study time-reversal~(T) asymmetries in the charmless two-body decays of
antitriplet bottom baryons. We find that in ${\bf B}_b \to {\bf B}_n P$ with
${\bf B}_b = (\Xi _b ^- , \,\Xi_b^0, \,\Lambda_b)$ and ${\bf B}_n(P)$ a octet
baryon (pseudoscalar meson), the positive and negative helicity amplitudes are
both sizable, resulting in the large T-violating effects. Particularly, the
T-odd parameters, $\beta_w$, for the color-enhanced channels are expected to be
around $40\%$ and $-25\%$ in $b\to s $ and $b\to d $ transitions for the
standard model, which can be measured by the experiments at LHCb, respectively.
On the other hand, in ${\bf B}_b \to {\bf B}_n V(\gamma)$ with $V(\gamma)$ a
vector meson~(photon), the decays are predominated by a single helicity
amplitude, and the T violating effects by the correlations among spins are
suppressed. We also explore the T violating observables for the $\Xi_b$ decays
based on the angular distributions.
| [
{
"created": "Wed, 3 Nov 2021 09:19:20 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Jan 2022 05:36:20 GMT",
"version": "v2"
}
] | 2022-02-09 | [
[
"Liu",
"Chia-Wei",
""
],
[
"Geng",
"Chao-Qiang",
""
]
] | We study time-reversal~(T) asymmetries in the charmless two-body decays of antitriplet bottom baryons. We find that in ${\bf B}_b \to {\bf B}_n P$ with ${\bf B}_b = (\Xi _b ^- , \,\Xi_b^0, \,\Lambda_b)$ and ${\bf B}_n(P)$ a octet baryon (pseudoscalar meson), the positive and negative helicity amplitudes are both sizable, resulting in the large T-violating effects. Particularly, the T-odd parameters, $\beta_w$, for the color-enhanced channels are expected to be around $40\%$ and $-25\%$ in $b\to s $ and $b\to d $ transitions for the standard model, which can be measured by the experiments at LHCb, respectively. On the other hand, in ${\bf B}_b \to {\bf B}_n V(\gamma)$ with $V(\gamma)$ a vector meson~(photon), the decays are predominated by a single helicity amplitude, and the T violating effects by the correlations among spins are suppressed. We also explore the T violating observables for the $\Xi_b$ decays based on the angular distributions. |
2403.07981 | Neil Christensen | Neil Christensen | SPINAS: Spinor Amplitude Subroutines for Constructive Diagram
Evaluations | 39 pages, 0 figures | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | SPINAS is a C++ package created for the implementation and numerical
computation of phase-space points of constructive amplitudes in particle
physics. This package contains a suite of classes and methods for handling
particles, propagators, spinor products, and processes. SPINAS is structured to
offer straightforward usability while ensuring maximum efficiency. This is
achieved through a design that emphasizes the storage and reuse of intermediate
results within amplitude calculations for each phase-space point. We include a
user guide describing how to use the components, a complete example of how to
use SPINAS for a scattering amplitude, a discussion of the design and
implementation useful for those wishing to contribute, and a discussion of our
validation of this package, including both a validation of individual
components of the package and a comparison of a complete set of Standard Model
processes with Feynman diagrams.
| [
{
"created": "Tue, 12 Mar 2024 18:00:03 GMT",
"version": "v1"
}
] | 2024-03-14 | [
[
"Christensen",
"Neil",
""
]
] | SPINAS is a C++ package created for the implementation and numerical computation of phase-space points of constructive amplitudes in particle physics. This package contains a suite of classes and methods for handling particles, propagators, spinor products, and processes. SPINAS is structured to offer straightforward usability while ensuring maximum efficiency. This is achieved through a design that emphasizes the storage and reuse of intermediate results within amplitude calculations for each phase-space point. We include a user guide describing how to use the components, a complete example of how to use SPINAS for a scattering amplitude, a discussion of the design and implementation useful for those wishing to contribute, and a discussion of our validation of this package, including both a validation of individual components of the package and a comparison of a complete set of Standard Model processes with Feynman diagrams. |
1603.09527 | Simone Pacetti | Earle L. Lomon and Simone Pacetti | Analytic pion form factor | 10 pages, 7 figures | Phys. Rev. D 94, 056002 (2016) | 10.1103/PhysRevD.94.056002 | MIT-CTP/4795 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The pion electromagnetic form factor and two-pion production in
electron-positron collisions are simultaneously fitted by a vector dominance
model evolving to perturbative QCD at large momentum transfer. This model was
previously successful in simultaneously fitting the nucleon electromagnetic
form factors (spacelike region) and the electromagnetic production of
nucleon-antinucleon pairs (timelike region). For this pion case dispersion
relations are used to produce the analytic connection of the spacelike and
timelike regions. The fit to all the data is good, especially for the newer
sets of time-like data. The description of high-$q^2$ data, in the time-like
region, requires one more meson with $\rho$ quantum numbers than listed in the
2014 Particle Data Group review.
| [
{
"created": "Thu, 31 Mar 2016 11:21:55 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Aug 2016 05:22:44 GMT",
"version": "v2"
},
{
"created": "Fri, 9 Sep 2016 08:35:24 GMT",
"version": "v3"
}
] | 2016-09-14 | [
[
"Lomon",
"Earle L.",
""
],
[
"Pacetti",
"Simone",
""
]
] | The pion electromagnetic form factor and two-pion production in electron-positron collisions are simultaneously fitted by a vector dominance model evolving to perturbative QCD at large momentum transfer. This model was previously successful in simultaneously fitting the nucleon electromagnetic form factors (spacelike region) and the electromagnetic production of nucleon-antinucleon pairs (timelike region). For this pion case dispersion relations are used to produce the analytic connection of the spacelike and timelike regions. The fit to all the data is good, especially for the newer sets of time-like data. The description of high-$q^2$ data, in the time-like region, requires one more meson with $\rho$ quantum numbers than listed in the 2014 Particle Data Group review. |
2102.04280 | Guo-Yuan Huang | Guo-yuan Huang and Werner Rodejohann | Solving the Hubble tension without spoiling Big Bang Nucleosynthesis | 9 pages, 4 figures | Phys. Rev. D 103, 123007 (2021) | 10.1103/PhysRevD.103.123007 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Hubble parameter inferred from cosmic microwave background observations
is consistently lower than that from local measurements, which could hint
towards new physics. Solutions to the Hubble tension typically require a
sizable amount of extra radiation $\Delta N^{}_{\rm eff}$ during recombination.
However, the amount of $\Delta N^{}_{\rm eff}$ in the early Universe is
unavoidably constrained by Big Bang Nucleosynthesis (BBN), which causes
problems for such solutions. We present a possibility to evade this problem by
introducing neutrino self-interactions via a simple Majoron-like coupling. The
scalar is slightly heavier than $1~{\rm MeV}$ and allowed to be fully
thermalized throughout the BBN era. The rise of neutrino temperature due to the
entropy transfer via $\phi \to \nu\overline{\nu}$ reactions compensates the
effect of a large $\Delta N^{}_{\rm eff}$ on BBN. Values of $\Delta N^{}_{\rm
eff}$ as large as $0.7$ are in this case compatible with BBN. We perform a fit
to the parameter space of the model.
| [
{
"created": "Mon, 8 Feb 2021 15:33:31 GMT",
"version": "v1"
}
] | 2021-06-16 | [
[
"Huang",
"Guo-yuan",
""
],
[
"Rodejohann",
"Werner",
""
]
] | The Hubble parameter inferred from cosmic microwave background observations is consistently lower than that from local measurements, which could hint towards new physics. Solutions to the Hubble tension typically require a sizable amount of extra radiation $\Delta N^{}_{\rm eff}$ during recombination. However, the amount of $\Delta N^{}_{\rm eff}$ in the early Universe is unavoidably constrained by Big Bang Nucleosynthesis (BBN), which causes problems for such solutions. We present a possibility to evade this problem by introducing neutrino self-interactions via a simple Majoron-like coupling. The scalar is slightly heavier than $1~{\rm MeV}$ and allowed to be fully thermalized throughout the BBN era. The rise of neutrino temperature due to the entropy transfer via $\phi \to \nu\overline{\nu}$ reactions compensates the effect of a large $\Delta N^{}_{\rm eff}$ on BBN. Values of $\Delta N^{}_{\rm eff}$ as large as $0.7$ are in this case compatible with BBN. We perform a fit to the parameter space of the model. |
2305.11775 | Rinku Maji | Rinku Maji, Wan-Il Park, Qaisar Shafi | Gravitational waves from walls bounded by strings in $SO(10)$ model of
pseudo-Goldstone dark matter | 8 pages, 3 figures, version published in PLB | Physics Letters B 845 (2023) 138127 | 10.1016/j.physletb.2023.138127 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore the gravitational wave spectrum generated by string-wall
structures in an $SO(10)$ ($Spin(10)$) based scenario of pseudo-Goldstone boson
dark matter (pGDM) particle. This dark matter candidate is a linear combination
of the Standard Model (SM) singlets present in the 126 and 16 dimensional Higgs
fields. The Higgs $126$-plet vacuum expectation value (VEV)
$\left<126_H\right>$ leaves unbroken the $\mathbb{Z}_2$ subgroup of
$\mathbb{Z}_4$, the center of $SO(10)$. Among other things, this yields
topologically stable cosmic strings with a string tension $\mu \sim
\left<126_H\right>^2$. The subsequent (spontaneous) breaking of $\mathbb{Z}_2$
at a significantly lower scale by the $16$-plet VEV $\left<16_H\right>$ leads
to the appearance of domain walls bounded by the strings produced earlier. We
display the gravitational wave spectrum for $G \mu$ values varying between
$10^{-15}$ and $10^{-9}$ ($\left<126_H\right>\sim 10^{11}$ - $10^{14}$ GeV),
and $\left<16_H\right>\sim 0.1$ - $10^2$ TeV range ($G$ denotes Newton's
constant.) These predictions can be tested, as we show, by a variety of
(proposed) experiments including LISA, ET, CE and others.
| [
{
"created": "Fri, 19 May 2023 16:03:39 GMT",
"version": "v1"
},
{
"created": "Mon, 4 Sep 2023 03:16:40 GMT",
"version": "v2"
}
] | 2023-09-07 | [
[
"Maji",
"Rinku",
""
],
[
"Park",
"Wan-Il",
""
],
[
"Shafi",
"Qaisar",
""
]
] | We explore the gravitational wave spectrum generated by string-wall structures in an $SO(10)$ ($Spin(10)$) based scenario of pseudo-Goldstone boson dark matter (pGDM) particle. This dark matter candidate is a linear combination of the Standard Model (SM) singlets present in the 126 and 16 dimensional Higgs fields. The Higgs $126$-plet vacuum expectation value (VEV) $\left<126_H\right>$ leaves unbroken the $\mathbb{Z}_2$ subgroup of $\mathbb{Z}_4$, the center of $SO(10)$. Among other things, this yields topologically stable cosmic strings with a string tension $\mu \sim \left<126_H\right>^2$. The subsequent (spontaneous) breaking of $\mathbb{Z}_2$ at a significantly lower scale by the $16$-plet VEV $\left<16_H\right>$ leads to the appearance of domain walls bounded by the strings produced earlier. We display the gravitational wave spectrum for $G \mu$ values varying between $10^{-15}$ and $10^{-9}$ ($\left<126_H\right>\sim 10^{11}$ - $10^{14}$ GeV), and $\left<16_H\right>\sim 0.1$ - $10^2$ TeV range ($G$ denotes Newton's constant.) These predictions can be tested, as we show, by a variety of (proposed) experiments including LISA, ET, CE and others. |
hep-ph/9710398 | Alexander L. Bondarev | Alexander L. Bondarev (NC PHEP, Minsk, Belarus) | Methods of Minimization of Calculations in High Energy Physics: 1. A
Covariant Method of the Calculation of Amplitudes of Processes Involving
Polarized Dirac Particles | 38 pages, LaTeX | null | null | null | hep-ph hep-th | null | The article deals with a number of the existings variants of direct
calculation of amplitudes of processes with polarized Dirac particles. It is
shown, that all of them are special cases of one and the same mathematical
scheme. The advantages and disadvantages of this scheme are considered. A new
variant of the method of calculation of amplitudes, keeping all the advantages
of this scheme, but free from disadvantages, is proposed. In particular, this
variant is suitable for the evaluation of amplitudes of processes with
interfering diagrams and does not need any additional calculations, that are
necessary in the general case. Expressions for the amplitudes of processes
involving both massive and massless particles are presented. These expressions
make it possible to create in an easy way the computer programs for automatic
calculation of amplitudes. The existing computer programs for calculation of
amplitudes, their limitations and disadvantages are briefly considered.
| [
{
"created": "Sat, 18 Oct 1997 19:44:49 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Feb 1998 20:09:43 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Bondarev",
"Alexander L.",
"",
"NC PHEP, Minsk, Belarus"
]
] | The article deals with a number of the existings variants of direct calculation of amplitudes of processes with polarized Dirac particles. It is shown, that all of them are special cases of one and the same mathematical scheme. The advantages and disadvantages of this scheme are considered. A new variant of the method of calculation of amplitudes, keeping all the advantages of this scheme, but free from disadvantages, is proposed. In particular, this variant is suitable for the evaluation of amplitudes of processes with interfering diagrams and does not need any additional calculations, that are necessary in the general case. Expressions for the amplitudes of processes involving both massive and massless particles are presented. These expressions make it possible to create in an easy way the computer programs for automatic calculation of amplitudes. The existing computer programs for calculation of amplitudes, their limitations and disadvantages are briefly considered. |
hep-ph/9911321 | Yosef Nir | Yosef Nir | CP Violation In and Beyond the Standard Model | 85 pages, harvmac, Lectures given in the XXVII SLAC Summer Institute
on Particle Physics, July 7 - 16, 1999. v2: references added | null | null | IASSNS-HEP-99-96 | hep-ph | null | The special features of CP violation in the Standard Model are presented. The
significance of measuring CP violation in B, K and D decays is explained. The
predictions of the Standard Model for CP asymmetries in B decays are analyzed
in detail. Then, four frameworks of new physics are reviewed: (i) Supersymmetry
provides an excellent demonstration of the power of CP violation as a probe of
new physics. (ii) Left-right symmetric models are discussed as an example of an
extension of the gauge sector. CP violation suggests that the scale of LRS
breaking is low. (iii) The variety of extensions of the scalar sector are
presented and their unique CP violating signatures are emphasized. (iv)
Vector-like down quarks are presented as an example of an extension of the
fermion sector. Their implications for CP asymmetries in B decays are highly
interesting.
| [
{
"created": "Thu, 11 Nov 1999 22:11:05 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Nov 1999 19:17:02 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Nir",
"Yosef",
""
]
] | The special features of CP violation in the Standard Model are presented. The significance of measuring CP violation in B, K and D decays is explained. The predictions of the Standard Model for CP asymmetries in B decays are analyzed in detail. Then, four frameworks of new physics are reviewed: (i) Supersymmetry provides an excellent demonstration of the power of CP violation as a probe of new physics. (ii) Left-right symmetric models are discussed as an example of an extension of the gauge sector. CP violation suggests that the scale of LRS breaking is low. (iii) The variety of extensions of the scalar sector are presented and their unique CP violating signatures are emphasized. (iv) Vector-like down quarks are presented as an example of an extension of the fermion sector. Their implications for CP asymmetries in B decays are highly interesting. |
2109.01015 | Luciano Abreu | Luciano M. Abreu and Felipe J. Llanes-Estrada | Triangle singularities waning in Heavy Ion Collisions: the case of
$Y(4260)\to \pi (\pi J/\psi)$ | 5 pages, 4 figures. Contribution to the proceedings of the 24th
High-Energy Physics International Conference in Quantum ChromoDynamics
(QCD21), 5-9 Jul 2021 Montpellier-France | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have recently observed that hadron triangle singularities, that can mock
new exotic hadrons, can be significanttly suppressed in relativistic heavy ion
collisions, provided two conditions are met: these are, first, that the
fireball lives long enough so that the triangle process has enough time to
complete in the Norton-Coleman classical sense, and second, that the mass
and/or width of the particles in the triangle diagram are sufficiently modified
from their vacuum values. Here we add a very interesting example to the canon,
which is $Y(4260) \to D_1 D \to \pi D^* D \to \pi + J/\psi \pi$. This reaction
has been proposed as a mechanism to explain the appearance of $Z_c(3900)$ in
the $J/\psi \pi$ spectrum. If the two muons and two pions reconstructing the
initial-state $Y$ can be isolated from the combinatorial background, then the
mechanism can provide a spectroscopy test: presence of $Y(4260)$ but absence of
$Z_c(3900)$ would be more indicative of such triangle mechanism, while presence
of both would rather point out to $Z_c$ being an exotic hadron.
| [
{
"created": "Thu, 2 Sep 2021 15:22:48 GMT",
"version": "v1"
}
] | 2021-09-03 | [
[
"Abreu",
"Luciano M.",
""
],
[
"Llanes-Estrada",
"Felipe J.",
""
]
] | We have recently observed that hadron triangle singularities, that can mock new exotic hadrons, can be significanttly suppressed in relativistic heavy ion collisions, provided two conditions are met: these are, first, that the fireball lives long enough so that the triangle process has enough time to complete in the Norton-Coleman classical sense, and second, that the mass and/or width of the particles in the triangle diagram are sufficiently modified from their vacuum values. Here we add a very interesting example to the canon, which is $Y(4260) \to D_1 D \to \pi D^* D \to \pi + J/\psi \pi$. This reaction has been proposed as a mechanism to explain the appearance of $Z_c(3900)$ in the $J/\psi \pi$ spectrum. If the two muons and two pions reconstructing the initial-state $Y$ can be isolated from the combinatorial background, then the mechanism can provide a spectroscopy test: presence of $Y(4260)$ but absence of $Z_c(3900)$ would be more indicative of such triangle mechanism, while presence of both would rather point out to $Z_c$ being an exotic hadron. |
2011.08313 | Bahram Shakerin | B. Shakerin, B.F.L. Ward | IR-improved DGLAP parton shower effects for associated production of a W
boson and jets in pp collisions at $\sqrt{s}=$8 and 13 TeV | 42 pages, 38 figures. To appear in IJMPA | International Journal of Modern Physics A Vol. 35 (2020) 2050197 | 10.1142/S0217751X20501973 | BU-HEPP-19-05 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a previous paper, hereafter referred to as I, we have analyzed the 7 TeV
LHC data on W + jets events from the standpoint of IR-improved DGLAP parton
shower effects, using the IR-improved Herwiri1.031 parton shower MC in
comparison with the Herwig6.5 parton shower MC in the context of the exact
$O(\alpha_s)$ matrix element matched parton shower framework provided by
MG5\_aMC@NLO. In the current paper, we extend this analysis to the LHC 8 and 13
TeV data to investigate the energy dependence of the results obtained in I.
Specifically, W~+ jet events are generated in the MADGRAPH5\_aMC@NLO framework
and showered by HERWIG6.521 and HERWIRI1.031 with $\mathtt{PTRMS}=2.2$ and 0
GeV, respectively. The differential cross sections are reported as functions of
jet multiplicity, transverse linear momenta ($P_{T}$), the jet pesudo-rapidity
($\eta$) and the scalar sum of jet transverse momenta ($H_{T}$) for different
jet multiplicities 1--3. The dijet cross sections as functions of transverse
linear momenta, invariant mass of the dijet and the jet separation are shown as
well. Distributions of angular correlations between the jets and the muon are
examined as well and the corresponding cross sections are presented. The
respective measured cross sections are compared with the exact
next-to-leading-order (NLO) matrix element matched parton shower theoretical
predictions provided by MADGRAPH5\_aMC@NLO/HERWIRI1.031~($\mathtt{PTRMS}=0)$
and MADGRAPH5\_aMC@NLO/HERWIG6.521~($\mathtt{PTRMS}=2.2~\mathrm{GeV})$ and the
phenomenological consequences are discussed with an eye toward their energy
dependence.
| [
{
"created": "Mon, 16 Nov 2020 22:24:47 GMT",
"version": "v1"
}
] | 2020-11-18 | [
[
"Shakerin",
"B.",
""
],
[
"Ward",
"B. F. L.",
""
]
] | In a previous paper, hereafter referred to as I, we have analyzed the 7 TeV LHC data on W + jets events from the standpoint of IR-improved DGLAP parton shower effects, using the IR-improved Herwiri1.031 parton shower MC in comparison with the Herwig6.5 parton shower MC in the context of the exact $O(\alpha_s)$ matrix element matched parton shower framework provided by MG5\_aMC@NLO. In the current paper, we extend this analysis to the LHC 8 and 13 TeV data to investigate the energy dependence of the results obtained in I. Specifically, W~+ jet events are generated in the MADGRAPH5\_aMC@NLO framework and showered by HERWIG6.521 and HERWIRI1.031 with $\mathtt{PTRMS}=2.2$ and 0 GeV, respectively. The differential cross sections are reported as functions of jet multiplicity, transverse linear momenta ($P_{T}$), the jet pesudo-rapidity ($\eta$) and the scalar sum of jet transverse momenta ($H_{T}$) for different jet multiplicities 1--3. The dijet cross sections as functions of transverse linear momenta, invariant mass of the dijet and the jet separation are shown as well. Distributions of angular correlations between the jets and the muon are examined as well and the corresponding cross sections are presented. The respective measured cross sections are compared with the exact next-to-leading-order (NLO) matrix element matched parton shower theoretical predictions provided by MADGRAPH5\_aMC@NLO/HERWIRI1.031~($\mathtt{PTRMS}=0)$ and MADGRAPH5\_aMC@NLO/HERWIG6.521~($\mathtt{PTRMS}=2.2~\mathrm{GeV})$ and the phenomenological consequences are discussed with an eye toward their energy dependence. |
hep-ph/9907480 | Max Chaves | M. Chaves and H. Morales | The Standard Model and the Generalized Covariant Derivative | 8 pages, no figures. To be published in the proceedings of the
International Workshop "Lorentz Group, CPT and Neutrinos", (Zacatecas,
Mexico, June 23-26, 1999) | null | null | null | hep-ph hep-th | null | The generalized covariant derivative, that uses both scalar and vector
bosons, is defined. It is shown how a grand unified theory of the Standard
Model can be constructed using a generalized Yang-Mills theory.
| [
{
"created": "Fri, 23 Jul 1999 23:07:59 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Chaves",
"M.",
""
],
[
"Morales",
"H.",
""
]
] | The generalized covariant derivative, that uses both scalar and vector bosons, is defined. It is shown how a grand unified theory of the Standard Model can be constructed using a generalized Yang-Mills theory. |
1808.08358 | Bao-Xi Sun | Da-Ming Wan, Si-Yu Zhao and Bao-Xi Sun | The $K\bar{K}^*$ interaction in the unitary coupled-channel
approximation | 10 pages, 1 figure and 1 table | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $K\bar{K}^*$ interaction Lagrangian is constructed when the $SU(3)$
hidden gauge symmetry is taken into account, and then the $K\bar{K}^*$
potential is obtained. In the low energy region, the $K\bar{K}^*$ potential
mainly comes from the contribution of the $t-$channel interaction by exchanging
$\rho$,$\omega$ and $\varphi$ mesons, respectively. The $K\bar{K}^*$ amplitude
is investigated by solving the Bethe-Salpeter equation in the unitary
coupled-channel approximation, where the loop function of the vector and
pseudoscalar mesons are evaluated in the dimensional regularization scheme, and
the contribution of the longitudinal part of the intermediate vector meson
propagator is included in the calculation. Finally, it is found that a
resonance state of $K\bar{K}^*$ is generated in the isospin $I=0$ sector, which
might correspond to the $f_1(1420)$ particle in the review of the particle data
group(PDG). Moreover, in the isospin $I=1$ sector, a pole of the $K\bar{K}^*$
amplitude is detected at $1425-i316$MeV on the complex plane of the total
energy in the center of mass system, which is higher than the $K\bar{K}^*$
threshold. Thus this pole might be a resonance state of $K\bar{K}^*$ although
no counterpart has been found in the PDG review.
| [
{
"created": "Sat, 25 Aug 2018 05:44:06 GMT",
"version": "v1"
}
] | 2018-08-28 | [
[
"Wan",
"Da-Ming",
""
],
[
"Zhao",
"Si-Yu",
""
],
[
"Sun",
"Bao-Xi",
""
]
] | The $K\bar{K}^*$ interaction Lagrangian is constructed when the $SU(3)$ hidden gauge symmetry is taken into account, and then the $K\bar{K}^*$ potential is obtained. In the low energy region, the $K\bar{K}^*$ potential mainly comes from the contribution of the $t-$channel interaction by exchanging $\rho$,$\omega$ and $\varphi$ mesons, respectively. The $K\bar{K}^*$ amplitude is investigated by solving the Bethe-Salpeter equation in the unitary coupled-channel approximation, where the loop function of the vector and pseudoscalar mesons are evaluated in the dimensional regularization scheme, and the contribution of the longitudinal part of the intermediate vector meson propagator is included in the calculation. Finally, it is found that a resonance state of $K\bar{K}^*$ is generated in the isospin $I=0$ sector, which might correspond to the $f_1(1420)$ particle in the review of the particle data group(PDG). Moreover, in the isospin $I=1$ sector, a pole of the $K\bar{K}^*$ amplitude is detected at $1425-i316$MeV on the complex plane of the total energy in the center of mass system, which is higher than the $K\bar{K}^*$ threshold. Thus this pole might be a resonance state of $K\bar{K}^*$ although no counterpart has been found in the PDG review. |
0706.3987 | Cristina Manuel | Massimo Mannarelli and Cristina Manuel | Exciting the quark-gluon plasma with a relativistic jet | 2 pages, 2 figures. Presented at "Heavy Ion Collisions at the LHC:
Last Call for Predictions", CERN, Geneva, May-June 2007 | null | null | null | hep-ph | null | We discuss the properties of a system composed by a static plasma traversed
by a jet of particles. Assuming that both the jet and the plasma can be
described using a hydrodynamical approach, and in the conformal limit, we find
that unstable modes arise when the velocity of the jet is larger than the speed
of the sound of the plasma and only modes with momenta smaller than a certain
values are unstable. Moreover, for ultrarelativistic velocities of the jet the
most unstable modes correspond to relative angles between the velocity of the
jet and momentum of the collective mode ~ pi/4. Our results suggest an
alternative mechanism for the description of the jet quenching phenomenon,
where the jet crossing the plasma loses energy exciting colored unstable modes.
In LHC this effect should be seen with an enhanced production of hadrons for
some specific values of their momenta and in certain directions of momenta
space.
| [
{
"created": "Wed, 27 Jun 2007 09:20:35 GMT",
"version": "v1"
}
] | 2007-06-28 | [
[
"Mannarelli",
"Massimo",
""
],
[
"Manuel",
"Cristina",
""
]
] | We discuss the properties of a system composed by a static plasma traversed by a jet of particles. Assuming that both the jet and the plasma can be described using a hydrodynamical approach, and in the conformal limit, we find that unstable modes arise when the velocity of the jet is larger than the speed of the sound of the plasma and only modes with momenta smaller than a certain values are unstable. Moreover, for ultrarelativistic velocities of the jet the most unstable modes correspond to relative angles between the velocity of the jet and momentum of the collective mode ~ pi/4. Our results suggest an alternative mechanism for the description of the jet quenching phenomenon, where the jet crossing the plasma loses energy exciting colored unstable modes. In LHC this effect should be seen with an enhanced production of hadrons for some specific values of their momenta and in certain directions of momenta space. |
2007.00029 | Kre\v{s}imir Kumeri\v{c}ki | Marija Cuic, Kresimir Kumericki and Andreas Schafer | Separation of Quark Flavors using DVCS Data | 6 pages, 5 figures | null | null | ZTF-EP-20-04 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the available data on deeply virtual Compton scattering (DVCS) off
protons and utilizing neural networks enhanced by the dispersion relation
constraint, we determine six out of eight leading Compton form factors in the
valence quark kinematic region. Furthermore, adding recent data on DVCS off
neutrons, we separate contributions of up and down quarks to the dominant form
factor, thus paving the way towards a three-dimensional picture of the nucleon.
| [
{
"created": "Tue, 30 Jun 2020 18:02:00 GMT",
"version": "v1"
}
] | 2020-07-02 | [
[
"Cuic",
"Marija",
""
],
[
"Kumericki",
"Kresimir",
""
],
[
"Schafer",
"Andreas",
""
]
] | Using the available data on deeply virtual Compton scattering (DVCS) off protons and utilizing neural networks enhanced by the dispersion relation constraint, we determine six out of eight leading Compton form factors in the valence quark kinematic region. Furthermore, adding recent data on DVCS off neutrons, we separate contributions of up and down quarks to the dominant form factor, thus paving the way towards a three-dimensional picture of the nucleon. |
hep-ph/9308280 | null | J. Garriga | Nucleation Rates in Flat and Curved Space | 57 pages, TUTP-10-93 | Phys.Rev.D49:6327-6342,1994 | 10.1103/PhysRevD.49.6327 | null | hep-ph gr-qc hep-th | null | Nucleation rates for tunneling processes in Minkowski and de Sitter space are
investigated, taking into account one loop prefactors. In particular, we con-
sider the creation of membranes by an antisymmetric tensor field, analogous to
Schwinger pair production. This can be viewed as a model for the decay of false
(or true) vacuum at zero temperature, in the thin wall limit. Also considered
is the spontaneous nucleation of strings, domain walls and monopoles during
inflation. The instantons for these processes are spherical world-sheets or
world-lines embedded in flat or de Sitter backgrounds. We find the contribution
of such instantons to the semiclassical partition function, including one loop
corrections due to small fluctuations around the spherical worldsheet. We sug-
gest a prescription for obtaining the distribution of objects nucleated during
inflation. This can be seen as an extension of the usual formula, valid in flat
space, according to which the nucleation rate is twice the imaginary part of
the free energy. In addition, we use the method of Bogolubov transformations to
compute the rate of pair production by an electric field in 1+1 dimensional de
Sitter space, and compare the results to those obtained using the instanton me-
thod. Both results agree where they are expected to, not only in the exponen-
tial dependence but also in the prefactor, confirming the validity of instanton
techniques in de Sitter space. Throughout the paper, both the gravitational
field and the antisymmetric tensor field are assumed external.
| [
{
"created": "Mon, 16 Aug 1993 20:39:00 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Garriga",
"J.",
""
]
] | Nucleation rates for tunneling processes in Minkowski and de Sitter space are investigated, taking into account one loop prefactors. In particular, we con- sider the creation of membranes by an antisymmetric tensor field, analogous to Schwinger pair production. This can be viewed as a model for the decay of false (or true) vacuum at zero temperature, in the thin wall limit. Also considered is the spontaneous nucleation of strings, domain walls and monopoles during inflation. The instantons for these processes are spherical world-sheets or world-lines embedded in flat or de Sitter backgrounds. We find the contribution of such instantons to the semiclassical partition function, including one loop corrections due to small fluctuations around the spherical worldsheet. We sug- gest a prescription for obtaining the distribution of objects nucleated during inflation. This can be seen as an extension of the usual formula, valid in flat space, according to which the nucleation rate is twice the imaginary part of the free energy. In addition, we use the method of Bogolubov transformations to compute the rate of pair production by an electric field in 1+1 dimensional de Sitter space, and compare the results to those obtained using the instanton me- thod. Both results agree where they are expected to, not only in the exponen- tial dependence but also in the prefactor, confirming the validity of instanton techniques in de Sitter space. Throughout the paper, both the gravitational field and the antisymmetric tensor field are assumed external. |
1501.03283 | Poulose Poulose Dr. | Satendra Kumar, P. Poulose, Shibananda Sahoo | Study of Higgs-gauge boson anomalous couplings through $e^-e^+
\rightarrow W^-W^+H$ at ILC | pdflatex, 15 pages, 11 figures, 3 tables. arXiv admin note: text
overlap with arXiv:1408.3563. published version with minor changes in the
figure presentation, updated references | null | 10.1103/PhysRevD.91.073016 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, Higgs couplings with gauge bosons is probed through $e^-e^+
\rightarrow W^-W^+H$ in an effective Lagrangian framework. An ILC of 500 $GeV$
center of mass energy with possible beam polarization is considered for this
purpose. The reach of ILC with integrated luminosity of 300 $fb^{-1}$ in the
determination of both the CP-conserving and CP-violating parameters are
obtained. Sensitivity of the probe of each of these couplings on the presence
of other couplings is investigated. The most influential couplings parameters
are $\bar c_W=-\bar c_B$. Other parameters of significant effect are $\bar
c_{HW}$ and $\bar c_{HB}$ among the CP-conserving ones, and $\tilde c_{HW}$ and
$\tilde c_{HB}$ among the CP-violating ones. CP-violating parameter, $\tilde
c_\gamma$ seems to have very little influence on the process considered.
Detailed study of the angular distributions have presented a way to disentangle
the effect of some of these couplings.
| [
{
"created": "Wed, 14 Jan 2015 08:50:14 GMT",
"version": "v1"
},
{
"created": "Tue, 19 May 2015 07:36:03 GMT",
"version": "v2"
}
] | 2015-06-11 | [
[
"Kumar",
"Satendra",
""
],
[
"Poulose",
"P.",
""
],
[
"Sahoo",
"Shibananda",
""
]
] | In this work, Higgs couplings with gauge bosons is probed through $e^-e^+ \rightarrow W^-W^+H$ in an effective Lagrangian framework. An ILC of 500 $GeV$ center of mass energy with possible beam polarization is considered for this purpose. The reach of ILC with integrated luminosity of 300 $fb^{-1}$ in the determination of both the CP-conserving and CP-violating parameters are obtained. Sensitivity of the probe of each of these couplings on the presence of other couplings is investigated. The most influential couplings parameters are $\bar c_W=-\bar c_B$. Other parameters of significant effect are $\bar c_{HW}$ and $\bar c_{HB}$ among the CP-conserving ones, and $\tilde c_{HW}$ and $\tilde c_{HB}$ among the CP-violating ones. CP-violating parameter, $\tilde c_\gamma$ seems to have very little influence on the process considered. Detailed study of the angular distributions have presented a way to disentangle the effect of some of these couplings. |
1207.6812 | Ramona Vogt | R. Vogt (LLNL and UC Davis), R. E. Nelson (LLNL and UC Davis) and A.
D. Frawley (Florida State) | Improving the J/psi Production Baseline at RHIC and the LHC | Proceedings for Hard Probes 2012, Cagliari, Italy | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We assess the theoretical uncertainties on the inclusive J/psi production
cross section in the Color Evaporation Model (CEM) using values for the charm
quark mass, renormalization and factorization scales obtained from a fit to the
charm production data. We use our new results to provide improved baseline
comparison calculations at RHIC and the LHC. We also study cold matter effects
on J/psi production at leading relative to next-to-leading order in the CEM
within this approach.
| [
{
"created": "Mon, 30 Jul 2012 00:33:28 GMT",
"version": "v1"
}
] | 2012-07-31 | [
[
"Vogt",
"R.",
"",
"LLNL and UC Davis"
],
[
"Nelson",
"R. E.",
"",
"LLNL and UC Davis"
],
[
"Frawley",
"A. D.",
"",
"Florida State"
]
] | We assess the theoretical uncertainties on the inclusive J/psi production cross section in the Color Evaporation Model (CEM) using values for the charm quark mass, renormalization and factorization scales obtained from a fit to the charm production data. We use our new results to provide improved baseline comparison calculations at RHIC and the LHC. We also study cold matter effects on J/psi production at leading relative to next-to-leading order in the CEM within this approach. |
1201.6305 | Sven Heinemeyer | S. Heinemeyer, F. v. d. Pahlen, H. Rzehak, C. Schappacher | MSSM Higgs Bosons from Stop and Chargino Decays | 7 pages, 2 figures, talk given at the LCWS 2011, September 2011,
Granada, Spain | null | null | CERN-PH-TH/2012-022; KA-TP-03-2012 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Higgs bosons of the MSSM can be produced from the decay of SUSY
particles. We review the evalulation of two decay modes in the MSSM with
complex parameters (cMSSM). The first type is the decay of the heavy scalar top
quark to a lighter scalar quark and a Higgs boson. The second type is the decay
of the heavy chargino to a lighter chargino/neutralino and a Higgs boson. The
evaluation is based on a full one-loop calculation including hard QED and QCD
radiation. We find sizable contributions to many partial decay widths and
branching ratios. They are roughly of O(10%) of the tree-level results, but can
go up to 30% or higher. These contributions are important for the correct
interpretation of scalar top quark decays at a future linear e+e- collider.
| [
{
"created": "Mon, 30 Jan 2012 18:04:39 GMT",
"version": "v1"
}
] | 2015-03-13 | [
[
"Heinemeyer",
"S.",
""
],
[
"Pahlen",
"F. v. d.",
""
],
[
"Rzehak",
"H.",
""
],
[
"Schappacher",
"C.",
""
]
] | The Higgs bosons of the MSSM can be produced from the decay of SUSY particles. We review the evalulation of two decay modes in the MSSM with complex parameters (cMSSM). The first type is the decay of the heavy scalar top quark to a lighter scalar quark and a Higgs boson. The second type is the decay of the heavy chargino to a lighter chargino/neutralino and a Higgs boson. The evaluation is based on a full one-loop calculation including hard QED and QCD radiation. We find sizable contributions to many partial decay widths and branching ratios. They are roughly of O(10%) of the tree-level results, but can go up to 30% or higher. These contributions are important for the correct interpretation of scalar top quark decays at a future linear e+e- collider. |
hep-ph/9502342 | Valentin Khoze | Valentin V. Khoze | Fermion Number Violation in the Background of a Gauge Field in Minkowski
Space | Few misprints are eliminated and the discussion leading to eqs.
(3.31) is reiterated. Accepted in Nucl. Phys. B, 29 Plain TEX pages plus 3
uuencoded PS figures. The hard copies of the figs are available from
valya.khoze@durham.ac.uk | Nucl.Phys. B445 (1995) 270-294 | 10.1016/0550-3213(95)00188-X | DTP/95/16 | hep-ph hep-th | null | Anomalous fermion number violation is studied in the background of a pure
SU(2) gauge field in Minkowski space using the method of N. Christ. It is
demonstrated that the chiral fermion number is violated by at most an integer
amount. Then the method is applied for a spherically symmetric Minkowski space
classical gauge field in the background. These classical gauge fields are
finite energy solutions to pure SU(2) equations of motion with in general
non-integer topological charge. We show that in the classical background which
during a finite time-interval matches such solutions the fermion number
violation is integer and non-zero. In particular, we calculate the violation of
the fermion number in the presence of L\"uscher-Schechter solutions. The
meaning of anomaly equation and applications to QCD and electroweak theory are
briefly discussed. We also comment on the relation of the results of this paper
to the previous work.
| [
{
"created": "Fri, 17 Feb 1995 18:54:05 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Feb 1995 11:19:14 GMT",
"version": "v2"
},
{
"created": "Tue, 16 May 1995 14:54:56 GMT",
"version": "v3"
},
{
"created": "Wed, 17 May 1995 10:02:39 GMT",
"version": "v4"
}
] | 2009-10-28 | [
[
"Khoze",
"Valentin V.",
""
]
] | Anomalous fermion number violation is studied in the background of a pure SU(2) gauge field in Minkowski space using the method of N. Christ. It is demonstrated that the chiral fermion number is violated by at most an integer amount. Then the method is applied for a spherically symmetric Minkowski space classical gauge field in the background. These classical gauge fields are finite energy solutions to pure SU(2) equations of motion with in general non-integer topological charge. We show that in the classical background which during a finite time-interval matches such solutions the fermion number violation is integer and non-zero. In particular, we calculate the violation of the fermion number in the presence of L\"uscher-Schechter solutions. The meaning of anomaly equation and applications to QCD and electroweak theory are briefly discussed. We also comment on the relation of the results of this paper to the previous work. |
1607.01165 | Thomas Becher | Thomas Becher | QCD and High Energy Interactions: Moriond 2016 Theory Summary | 14 pages, 5 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I summarize the theory talks presented at the 50 year anniversary conference.
The talks covered a wide range of topics, but common threads included
next-to-next-to-leading order predictions for many 2 -> 2 processes, beyond QCD
lattice simulations, work on the set of persistent flavor physics anomalies,
and discussions of the significance and possible explanations of the diphoton
excess at 750 GeV.
| [
{
"created": "Tue, 5 Jul 2016 09:31:15 GMT",
"version": "v1"
}
] | 2016-07-06 | [
[
"Becher",
"Thomas",
""
]
] | I summarize the theory talks presented at the 50 year anniversary conference. The talks covered a wide range of topics, but common threads included next-to-next-to-leading order predictions for many 2 -> 2 processes, beyond QCD lattice simulations, work on the set of persistent flavor physics anomalies, and discussions of the significance and possible explanations of the diphoton excess at 750 GeV. |
hep-ph/0605108 | Matteo Beccaria | M. Beccaria, G. Macorini, F.M. Renard, C. Verzegnassi | Single top production in the $t$-channel at LHC: a realistic test of
electroweak models | 28 pages, 10 eps figures | Phys.Rev.D74:013008,2006 | 10.1103/PhysRevD.74.013008 | PTA-06/14 | hep-ph | null | We compute the complete electroweak one-loop effect on the process of
$t$-channel single top production at LHC in the Standard Model and in the MSSM
within the mSUGRA symmetry breaking scheme. We find that the one-loop
electroweak SM effect is large, and decreases the cross section of an amount
that is of the same size as that of the NLO QCD one. The genuine SUSY effect in
the mSUGRA scheme, for a general choice of benchmark points, is rather small.
It might become large and visible in more general scenarios around thresholds
involving light stop and neutralino mass values.
| [
{
"created": "Wed, 10 May 2006 07:55:31 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Beccaria",
"M.",
""
],
[
"Macorini",
"G.",
""
],
[
"Renard",
"F. M.",
""
],
[
"Verzegnassi",
"C.",
""
]
] | We compute the complete electroweak one-loop effect on the process of $t$-channel single top production at LHC in the Standard Model and in the MSSM within the mSUGRA symmetry breaking scheme. We find that the one-loop electroweak SM effect is large, and decreases the cross section of an amount that is of the same size as that of the NLO QCD one. The genuine SUSY effect in the mSUGRA scheme, for a general choice of benchmark points, is rather small. It might become large and visible in more general scenarios around thresholds involving light stop and neutralino mass values. |
hep-ph/9412282 | Ulf Meissner | V. Bernard, N. Kaiser and Ulf-G. Mei{\ss}ner | Novel Pion Electroproduction Low-Energy Theorems | 6 pp, plain LaTeX, one figure available from the authors via fax or
normal mail | Phys.Rev.Lett. 74 (1995) 3752-3755 | 10.1103/PhysRevLett.74.3752 | CRN 94-66 and TK 94 19 | hep-ph nucl-th | null | We present novel low--energy theorems for the P--wave multipoles $2M_{1+} +
M_{1-}$, $M_{1+} -M_{1-}$, $E_{1+}$ and $L_{1\pm}$ for neutral pion
electroproduction off protons. These should be very useful for the analysis of
existing or future threshold data.
| [
{
"created": "Tue, 13 Dec 1994 08:52:14 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Bernard",
"V.",
""
],
[
"Kaiser",
"N.",
""
],
[
"Meißner",
"Ulf-G.",
""
]
] | We present novel low--energy theorems for the P--wave multipoles $2M_{1+} + M_{1-}$, $M_{1+} -M_{1-}$, $E_{1+}$ and $L_{1\pm}$ for neutral pion electroproduction off protons. These should be very useful for the analysis of existing or future threshold data. |
hep-ph/9905337 | Michael Strickland | Jens O. Andersen, Eric Braaten, and Michael Strickland | Hard-thermal-loop Resummation of the Thermodynamics of a Hot Gluon
Plasma | 35 pages, 6 figures | Phys.Rev.D61:014017,2000 | 10.1103/PhysRevD.61.014017 | null | hep-ph | null | We calculate the thermodynamic functions of a hot gluon plasma to leading
order in hard-thermal-loop (HTL) perturbation theory. Effects associated with
screening, gluon quasiparticles, and Landau damping are resummed to all orders.
The ultraviolet divergences generated by the HTL propagator corrections can be
cancelled by a counterterm that depends on the thermal gluon mass parameter.
The HTL thermodynamic functions are compared to those from lattice gauge theory
calculations and from quasiparticle models. For reasonable values of the HTL
parameters, the deviations from lattice results for T > 2 T_c have the correct
sign and roughly the correct magnitude to be accounted for by next-to-leading
order corrections in HTL perturbation theory.
| [
{
"created": "Fri, 14 May 1999 03:15:34 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Aug 1999 16:57:53 GMT",
"version": "v2"
},
{
"created": "Fri, 27 Aug 1999 20:43:43 GMT",
"version": "v3"
}
] | 2016-09-06 | [
[
"Andersen",
"Jens O.",
""
],
[
"Braaten",
"Eric",
""
],
[
"Strickland",
"Michael",
""
]
] | We calculate the thermodynamic functions of a hot gluon plasma to leading order in hard-thermal-loop (HTL) perturbation theory. Effects associated with screening, gluon quasiparticles, and Landau damping are resummed to all orders. The ultraviolet divergences generated by the HTL propagator corrections can be cancelled by a counterterm that depends on the thermal gluon mass parameter. The HTL thermodynamic functions are compared to those from lattice gauge theory calculations and from quasiparticle models. For reasonable values of the HTL parameters, the deviations from lattice results for T > 2 T_c have the correct sign and roughly the correct magnitude to be accounted for by next-to-leading order corrections in HTL perturbation theory. |
1811.08899 | Teppei Kitahara | Syuhei Iguro, Teppei Kitahara, Yuji Omura, Ryoutaro Watanabe, Kei
Yamamoto | $D^{\ast}$ polarization vs. $R_{D^{(\ast)}}$ anomalies in the leptoquark
models | 24 pages, 3 figures, 1 table; references added, version published in
JHEP | JHEP 1902 (2019) 194 | 10.1007/JHEP02(2019)194 | TTP18-037, ZU-TH-39/18 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Polarization measurements in $\bar{B} \to D^{(\ast)} \tau \overline{\nu}$ are
useful to check consistency in new physics explanations for the $R_{D}$ and
$R_{D^{\ast}}$ anomalies. In this paper, we investigate the $D^{\ast}$ and
$\tau$ polarizations and focus on the new physics contributions to the fraction
of a longitudinal $D^{\ast}$ polarization ($F_{L}^{D^{\ast}}$), which is
recently measured by the Belle collaboration $F_{L}^{D^{\ast}} = 0.60 \pm
0.09$, in model-independent manner and in each single leptoquark model (${\rm
R}_2$, ${\rm S}_1$ and ${\rm U}_1$) that can naturally explain the
$R_{D^{(\ast)}}$ anomalies. It is found that $\mathcal{B}(B_c^{+} \to \tau^{+}
\nu)$ severely restricts deviation from the Standard Model (SM) prediction of
$F_{L, \textrm{SM}}^{D^{\ast}} = 0.46 \pm 0.04$ in the leptoquark models:
[0.43, 0.44], [0.42, 0.48], and [0.43, 0.47] are predicted as a range of
$F_{L}^{D^{\ast}}$ for the ${\rm R}_2$, ${\rm S}_1$, and ${\rm U}_1$ leptoquark
models, respectively, where the current data of $R_{D^{(\ast)}}$ is satisfied
at $1\,\sigma$ level. It is also shown that the $\tau$ polarization observables
can much deviate from the SM predictions. The Belle II experiment, therefore,
can check such correlations between $R_{D^{(\ast)}}$ and the polarization
observables, and discriminate among the leptoquark models.
| [
{
"created": "Wed, 21 Nov 2018 19:00:00 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Dec 2018 21:09:27 GMT",
"version": "v2"
},
{
"created": "Mon, 4 Mar 2019 16:25:38 GMT",
"version": "v3"
}
] | 2019-03-05 | [
[
"Iguro",
"Syuhei",
""
],
[
"Kitahara",
"Teppei",
""
],
[
"Omura",
"Yuji",
""
],
[
"Watanabe",
"Ryoutaro",
""
],
[
"Yamamoto",
"Kei",
""
]
] | Polarization measurements in $\bar{B} \to D^{(\ast)} \tau \overline{\nu}$ are useful to check consistency in new physics explanations for the $R_{D}$ and $R_{D^{\ast}}$ anomalies. In this paper, we investigate the $D^{\ast}$ and $\tau$ polarizations and focus on the new physics contributions to the fraction of a longitudinal $D^{\ast}$ polarization ($F_{L}^{D^{\ast}}$), which is recently measured by the Belle collaboration $F_{L}^{D^{\ast}} = 0.60 \pm 0.09$, in model-independent manner and in each single leptoquark model (${\rm R}_2$, ${\rm S}_1$ and ${\rm U}_1$) that can naturally explain the $R_{D^{(\ast)}}$ anomalies. It is found that $\mathcal{B}(B_c^{+} \to \tau^{+} \nu)$ severely restricts deviation from the Standard Model (SM) prediction of $F_{L, \textrm{SM}}^{D^{\ast}} = 0.46 \pm 0.04$ in the leptoquark models: [0.43, 0.44], [0.42, 0.48], and [0.43, 0.47] are predicted as a range of $F_{L}^{D^{\ast}}$ for the ${\rm R}_2$, ${\rm S}_1$, and ${\rm U}_1$ leptoquark models, respectively, where the current data of $R_{D^{(\ast)}}$ is satisfied at $1\,\sigma$ level. It is also shown that the $\tau$ polarization observables can much deviate from the SM predictions. The Belle II experiment, therefore, can check such correlations between $R_{D^{(\ast)}}$ and the polarization observables, and discriminate among the leptoquark models. |
1509.04596 | Xin Liu | Defa Dou, Xin Liu, Jing-Wu Li, and Zhen-Jun Xiao | Large non-factorizable contributions in $B \to a_0 a_0$ decays | 17 pages, 3 figures, and 2 tables; references added, contents
improved, to appear in JPG, matching the published version | null | 10.1088/0954-3899/43/4/045001 | JSNU/PHY-TH-2015 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate three tree-dominated $B \to a_0 a_0$ decays for the first time
in the perturbative QCD(pQCD) approach at leading order in the standard model,
with $a_0$ standing for the light scalar $a_0(980)$ state, which is assumed as
a meson based on the model of conventional two-quark$(q\bar q)$ structure. All
the topologies of the Feynman diagrams such as the non-factorizable spectator
ones and the annihilation ones are calculated in the pQCD approach. It is of
great interest to find that, contrary to the known $B \to \pi \pi$ decays, the
$B \to a_0 a_0$ decays are governed by the large non-factorizable
contributions, which give rise to the large $B \to a_0 a_0$ decay rates in the
order of $10^{-6} \sim 10^{-5}$, although the $a_0$ meson has an extremely
small vector decay constant $f_{a_0}$. Also observed are large direct
CP-violating asymmetries around $15\%$ and $30\%$ for the $B^0 \to a_0^0 a_0^0$
and $a_0^+ a_0^-$ modes. These sizable predictions could be easily examined at
the running Large Hadron Collider and the near future Super-B/Belle-II
experiments. The future precision measurements combined with these pQCD
predictions might be helpful to explore the complicated QCD dynamics and the
inner structure of the light scalar $a_0$, as well as to complementarily
constrain the unitary angle $\alpha$.
| [
{
"created": "Tue, 15 Sep 2015 15:08:55 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Jan 2016 15:16:26 GMT",
"version": "v2"
}
] | 2016-03-23 | [
[
"Dou",
"Defa",
""
],
[
"Liu",
"Xin",
""
],
[
"Li",
"Jing-Wu",
""
],
[
"Xiao",
"Zhen-Jun",
""
]
] | We investigate three tree-dominated $B \to a_0 a_0$ decays for the first time in the perturbative QCD(pQCD) approach at leading order in the standard model, with $a_0$ standing for the light scalar $a_0(980)$ state, which is assumed as a meson based on the model of conventional two-quark$(q\bar q)$ structure. All the topologies of the Feynman diagrams such as the non-factorizable spectator ones and the annihilation ones are calculated in the pQCD approach. It is of great interest to find that, contrary to the known $B \to \pi \pi$ decays, the $B \to a_0 a_0$ decays are governed by the large non-factorizable contributions, which give rise to the large $B \to a_0 a_0$ decay rates in the order of $10^{-6} \sim 10^{-5}$, although the $a_0$ meson has an extremely small vector decay constant $f_{a_0}$. Also observed are large direct CP-violating asymmetries around $15\%$ and $30\%$ for the $B^0 \to a_0^0 a_0^0$ and $a_0^+ a_0^-$ modes. These sizable predictions could be easily examined at the running Large Hadron Collider and the near future Super-B/Belle-II experiments. The future precision measurements combined with these pQCD predictions might be helpful to explore the complicated QCD dynamics and the inner structure of the light scalar $a_0$, as well as to complementarily constrain the unitary angle $\alpha$. |
2008.13304 | Xin-Nian Wang | Yayun He, Longgang Pang and Xin-Nian Wang | Gradient tomography of jet quenching in high-energy heavy-ion collisions | 4 pages in Latex format for POS with 4 PDF figures, prepared for
publication in the proceedings of Hard Probes 2020 conference, 1-6 June 2020,
Austin, Texas | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We illustrate with both a Boltzmann diffusion equation and full simulations
of jet propagation in heavy-ion collisions within the Linear Boltzmann
Transport (LBT) model that the spatial gradient of the jet transport
coefficient perpendicular to the propagation direction can lead to a drift and
asymmetry in the transverse momentum distribution. Such an asymmetry depends on
both the spatial position along the transverse gradience and the propagating
length. It can be used to localize the initial jet production positions for
more detailed studies of jet quenching and properties of the quark-gluon plasma
in heavy-ion collisions.
| [
{
"created": "Mon, 31 Aug 2020 00:23:00 GMT",
"version": "v1"
}
] | 2020-09-01 | [
[
"He",
"Yayun",
""
],
[
"Pang",
"Longgang",
""
],
[
"Wang",
"Xin-Nian",
""
]
] | We illustrate with both a Boltzmann diffusion equation and full simulations of jet propagation in heavy-ion collisions within the Linear Boltzmann Transport (LBT) model that the spatial gradient of the jet transport coefficient perpendicular to the propagation direction can lead to a drift and asymmetry in the transverse momentum distribution. Such an asymmetry depends on both the spatial position along the transverse gradience and the propagating length. It can be used to localize the initial jet production positions for more detailed studies of jet quenching and properties of the quark-gluon plasma in heavy-ion collisions. |
2212.03336 | Rudnei Ramos | Lucas G. C\^amara and Rudnei O. Ramos | Finite size effects in the phase transition patterns of coupled scalar
field systems | 19 pages, 8 figures. Many clarifications added. Version matching the
published one in the Physical Review D | Phys. Rev. D 107, 056021 (2023) | 10.1103/PhysRevD.107.056021 | null | hep-ph cond-mat.stat-mech hep-th | http://creativecommons.org/licenses/by/4.0/ | It is considered in this work the phase transition patterns for a coupled
two-scalar field system model under the combined effects of finite sizes and
temperature. The scalar fields are taken as propagating in a D=4 Euclidean
space with the usual periodic compactification in the Euclidean time direction
(with dimension given by the inverse of the temperature) and also under a
compact dimension in the space direction, which is restricted to size L. In the
latter case, a Dirichlet boundary condition is considered. Finite-size
variation of the critical temperature for the cases of symmetry restoration and
inverse symmetry breaking are studied. At fixed finite-temperature values, the
variation of the inverse correlation lengths with the size L might display a
behavior analogous to reentrant phase transitions. Possible applications of our
results to physical systems of interest are also discussed.
| [
{
"created": "Tue, 6 Dec 2022 21:39:16 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Mar 2023 17:08:50 GMT",
"version": "v2"
}
] | 2023-03-30 | [
[
"Câmara",
"Lucas G.",
""
],
[
"Ramos",
"Rudnei O.",
""
]
] | It is considered in this work the phase transition patterns for a coupled two-scalar field system model under the combined effects of finite sizes and temperature. The scalar fields are taken as propagating in a D=4 Euclidean space with the usual periodic compactification in the Euclidean time direction (with dimension given by the inverse of the temperature) and also under a compact dimension in the space direction, which is restricted to size L. In the latter case, a Dirichlet boundary condition is considered. Finite-size variation of the critical temperature for the cases of symmetry restoration and inverse symmetry breaking are studied. At fixed finite-temperature values, the variation of the inverse correlation lengths with the size L might display a behavior analogous to reentrant phase transitions. Possible applications of our results to physical systems of interest are also discussed. |
2208.03852 | Shinsuke Yoshida | Shinsuke Yoshida, Difei Zheng | Reformulation of the twist-3 gluon Sivers effect toward the application
to the heavy quarkonium production | 15 pages, 6 figures, to be published in Physical Review D | null | 10.1103/PhysRevD.106.034019 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this paper, we propose a new calculation method for the twist-3 gluon
Sivers effect within the collinear factorization approach. The method called
pole calculation has been used to derive the cross section formula for the
single transverse-spin asymmetry(SSA) as a standard method. We point out that
we encounter a problem when we try to apply the pole calculation to the SSA in
the heavy quarkonium production whose hadronization mechanism is described by
non-relativistic QCD(NRQCD) framework. We show that the new calculation method
solves this problem and successfully reproduces known results derived by the
pole calculation. Our new method extends the applicability of the twist-3
calculation technique to heavy quarkonium productions which are ideal
observables for the investigation of the gluon Sivers effect.
| [
{
"created": "Mon, 8 Aug 2022 00:23:32 GMT",
"version": "v1"
}
] | 2022-08-31 | [
[
"Yoshida",
"Shinsuke",
""
],
[
"Zheng",
"Difei",
""
]
] | In this paper, we propose a new calculation method for the twist-3 gluon Sivers effect within the collinear factorization approach. The method called pole calculation has been used to derive the cross section formula for the single transverse-spin asymmetry(SSA) as a standard method. We point out that we encounter a problem when we try to apply the pole calculation to the SSA in the heavy quarkonium production whose hadronization mechanism is described by non-relativistic QCD(NRQCD) framework. We show that the new calculation method solves this problem and successfully reproduces known results derived by the pole calculation. Our new method extends the applicability of the twist-3 calculation technique to heavy quarkonium productions which are ideal observables for the investigation of the gluon Sivers effect. |
1706.03891 | Savely G. Karshenboim | Andrzej Czarnecki, Savely G. Karshenboim | Decay of the dimuonium into a photon and a neutral pion | corrected and extended list of references | null | 10.1103/PhysRevD.96.011302 | Alberta Thy 28-16 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the decay rate of dimuonium into a neutral pion and a photon. We
find that approximately one in 10^5 ortho-dimuonia decays into this channel. We
also determine the contribution of the virtual photon-pion loop to the
hyperfine splitting in dimuonium and reproduce its leading effect in the
anomalous magnetic moment of the muon.
| [
{
"created": "Tue, 13 Jun 2017 02:25:02 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Jun 2017 08:02:55 GMT",
"version": "v2"
}
] | 2017-08-02 | [
[
"Czarnecki",
"Andrzej",
""
],
[
"Karshenboim",
"Savely G.",
""
]
] | We compute the decay rate of dimuonium into a neutral pion and a photon. We find that approximately one in 10^5 ortho-dimuonia decays into this channel. We also determine the contribution of the virtual photon-pion loop to the hyperfine splitting in dimuonium and reproduce its leading effect in the anomalous magnetic moment of the muon. |
2311.06469 | Wei Chao | Wei Chao, Ying-Quan Peng | Majorana Majoron and the Baryon Asymmetry of the Universe | 15 pages, 4 figures, comments are welcome! | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The spontaneous breaking of the global lepton number, an accidental symmetry
in the Standard Model of particle physics, results in a massless goldstone
boson, the Majoron, which can be taken as a cold dark matter candidate with
properties similar to these of the axion. In this letter, we propose a novel
mass generation mechanism for the Majoron via radiative corrections induced by
the interaction of a tiny lepton-number-violating (LNV) Majorana mass term of
right-handed neutrinos in the canonical seesaw mechanism. We show that this LNV
Majorana mass term not only generates the mass of the Majoron but also leads to
a non-zero initial velocity of the Majoron, which subsequently impacts on the
relic abundance of the Majoron generated in the early universe via the
misalignment mechanism. With the assistance of the Weinberg operator, the same
initial velocity may also generate the lepton asymmetry, which is subsequently
transported into the baryon asymmetry of the universe (BAU) via the weak
sphaleron process. As a result, the neutrino masses, dark matter and the BAU
can be addressed in this concise theoretical framework.
| [
{
"created": "Sat, 11 Nov 2023 03:40:01 GMT",
"version": "v1"
}
] | 2023-11-14 | [
[
"Chao",
"Wei",
""
],
[
"Peng",
"Ying-Quan",
""
]
] | The spontaneous breaking of the global lepton number, an accidental symmetry in the Standard Model of particle physics, results in a massless goldstone boson, the Majoron, which can be taken as a cold dark matter candidate with properties similar to these of the axion. In this letter, we propose a novel mass generation mechanism for the Majoron via radiative corrections induced by the interaction of a tiny lepton-number-violating (LNV) Majorana mass term of right-handed neutrinos in the canonical seesaw mechanism. We show that this LNV Majorana mass term not only generates the mass of the Majoron but also leads to a non-zero initial velocity of the Majoron, which subsequently impacts on the relic abundance of the Majoron generated in the early universe via the misalignment mechanism. With the assistance of the Weinberg operator, the same initial velocity may also generate the lepton asymmetry, which is subsequently transported into the baryon asymmetry of the universe (BAU) via the weak sphaleron process. As a result, the neutrino masses, dark matter and the BAU can be addressed in this concise theoretical framework. |
2211.16265 | Berndt Muller | Berndt M\"uller and Andreas Sch\"afer | Quark-Hadron Transition and Entanglement | null | null | null | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | The dual holographic description has enjoyed many successes in explaining
fundamental properties of the early stages of relativistic heavy ion collisions
up to the formation of a minimal-viscosity quark-gluon fluid. However, there
have been few attempts to extend its application beyond this stage. Here we
explore the prospects for such an extension beyond the time of hadronization.
Our discussion makes use of recent insights into the duality of entanglement
properties of field theory states in the edge of Anti-de Sitter space and
non-trivial topologies of horizons in the bulk, often referred to as ER = EPR
duality. We discuss this topic from the point of view of heavy-ion
phenomenology, review several relevant concepts, and map out a path toward
combining them into a comprehensive, at least semiquantitative description of
relativistic heavy ion collisions. We outline possible next steps in this
direction.
| [
{
"created": "Tue, 29 Nov 2022 14:53:01 GMT",
"version": "v1"
}
] | 2022-11-30 | [
[
"Müller",
"Berndt",
""
],
[
"Schäfer",
"Andreas",
""
]
] | The dual holographic description has enjoyed many successes in explaining fundamental properties of the early stages of relativistic heavy ion collisions up to the formation of a minimal-viscosity quark-gluon fluid. However, there have been few attempts to extend its application beyond this stage. Here we explore the prospects for such an extension beyond the time of hadronization. Our discussion makes use of recent insights into the duality of entanglement properties of field theory states in the edge of Anti-de Sitter space and non-trivial topologies of horizons in the bulk, often referred to as ER = EPR duality. We discuss this topic from the point of view of heavy-ion phenomenology, review several relevant concepts, and map out a path toward combining them into a comprehensive, at least semiquantitative description of relativistic heavy ion collisions. We outline possible next steps in this direction. |
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