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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/0501285 | Hongting Yang | Hongting Yang | Flavor-number dependence of QCD vacuum tensor susceptibilities | 7 pages, 3 tables | null | null | null | hep-ph | null | The values of quark condensate and tensor susceptibility of QCD vacuum are
calculated with different number of flavors. It is shown that, the values of
tensor susceptibility are obviously dependent on the flavor numbers while the
flavor-number dependence of quark condensate is undetermined.
| [
{
"created": "Mon, 31 Jan 2005 11:06:29 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Mar 2006 03:19:01 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Yang",
"Hongting",
""
]
] | The values of quark condensate and tensor susceptibility of QCD vacuum are calculated with different number of flavors. It is shown that, the values of tensor susceptibility are obviously dependent on the flavor numbers while the flavor-number dependence of quark condensate is undetermined. |
2408.03019 | Xin Guan | Xin Guan, Franz Herzog, Yao Ma, Bernhard Mistlberger and Adi Suresh | Splitting amplitudes at N$^3$LO in QCD | 17 pages, 4 figures | null | null | null | hep-ph hep-th | http://creativecommons.org/licenses/by/4.0/ | In the limit where partons become collinear to each other, scattering
amplitudes factorize into a product of universal, process-independent building
blocks and scattering amplitudes involving fewer partons. We compute these
universal building blocks -- known as splitting amplitudes -- for two collinear
QCD partons up to third loop order in QCD. Our results describe arbitrary
time-like splitting processes. Due to the violation of strict collinear
factorization in space-like splitting processes, we specifically present
space-like splitting amplitudes for three-parton QCD scattering amplitudes at
third loop order. To achieve our results, we perform a collinear expansion of
three-loop scattering amplitudes using a new expansion-by-subgraph technology,
which is based on the method of regions.
| [
{
"created": "Tue, 6 Aug 2024 08:02:20 GMT",
"version": "v1"
}
] | 2024-08-07 | [
[
"Guan",
"Xin",
""
],
[
"Herzog",
"Franz",
""
],
[
"Ma",
"Yao",
""
],
[
"Mistlberger",
"Bernhard",
""
],
[
"Suresh",
"Adi",
""
]
] | In the limit where partons become collinear to each other, scattering amplitudes factorize into a product of universal, process-independent building blocks and scattering amplitudes involving fewer partons. We compute these universal building blocks -- known as splitting amplitudes -- for two collinear QCD partons up to third loop order in QCD. Our results describe arbitrary time-like splitting processes. Due to the violation of strict collinear factorization in space-like splitting processes, we specifically present space-like splitting amplitudes for three-parton QCD scattering amplitudes at third loop order. To achieve our results, we perform a collinear expansion of three-loop scattering amplitudes using a new expansion-by-subgraph technology, which is based on the method of regions. |
1106.1956 | Pankaj Jain | Naveen K. Singh, Pankaj Jain, Subhadip Mitra, Sukanta Panda | Quantum Treatment of the Weyl Vector Meson | 19 pages, no figures, significantly revised, no change in results or
conclusions | null | 10.1103/PhysRevD.84.105037 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Weyl meson arises in theories with local scale invariance. It acts as a
candidate for dark matter in a generalized Standard Model with local scale
invariance. The Higgs particle is absent from the physical spectrum in this
theory. We consider the quantization of this theory in detail, imposing
suitable gauge fixing conditions. We also consider a further generalization of
this model which includes an additional real scalar field. In this theory a
Higgs like particle remains in the particle spectrum. Since this particle
couples to the Weyl meson, it can lead to interesting phenomenology involving
this vector field in particle colliders.
| [
{
"created": "Fri, 10 Jun 2011 05:11:34 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Oct 2011 10:14:03 GMT",
"version": "v2"
}
] | 2013-05-29 | [
[
"Singh",
"Naveen K.",
""
],
[
"Jain",
"Pankaj",
""
],
[
"Mitra",
"Subhadip",
""
],
[
"Panda",
"Sukanta",
""
]
] | The Weyl meson arises in theories with local scale invariance. It acts as a candidate for dark matter in a generalized Standard Model with local scale invariance. The Higgs particle is absent from the physical spectrum in this theory. We consider the quantization of this theory in detail, imposing suitable gauge fixing conditions. We also consider a further generalization of this model which includes an additional real scalar field. In this theory a Higgs like particle remains in the particle spectrum. Since this particle couples to the Weyl meson, it can lead to interesting phenomenology involving this vector field in particle colliders. |
2203.08166 | Guilllermo Gambini | James M. Cline, Guillermo Gambini | Constraints on Heavy Neutral Leptons interacting with a singlet scalar | 14 pages, 11 figures. v2 matches published version | null | 10.1103/PhysRevD.105.115035 | null | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | Heavy neutral leptons (HNLs) are an attractive minimal extension of the
Standard Model, as is a singlet scalar $s$ mixing with the Higgs boson. If both
are present, it is natural for HNLs to interact with $s$. For a light
singlet,the decay $N\to s\nu$ can dominate over weak HNL decays. We reinterpret
existing constraints on HNL mixing from the DELPHI, CHARM and Belle experiments
for 0.5-100 GeV mass HNLs, taking into account the new decay channel. Although
the constraints are typically weakened, in some cases they can become stronger,
due to observable $s\to\ell^+\ell^-$ decays in the detectors. The method
presented here could be used to recast constraints from other (older)
experiments without resorting to computationally expensive Monte Carlo
simulations. In addition, we update and correct some errors in the analysis of
the original constraints, in the absence of the singlet.
| [
{
"created": "Tue, 15 Mar 2022 18:00:09 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Jun 2022 15:54:01 GMT",
"version": "v2"
}
] | 2022-06-27 | [
[
"Cline",
"James M.",
""
],
[
"Gambini",
"Guillermo",
""
]
] | Heavy neutral leptons (HNLs) are an attractive minimal extension of the Standard Model, as is a singlet scalar $s$ mixing with the Higgs boson. If both are present, it is natural for HNLs to interact with $s$. For a light singlet,the decay $N\to s\nu$ can dominate over weak HNL decays. We reinterpret existing constraints on HNL mixing from the DELPHI, CHARM and Belle experiments for 0.5-100 GeV mass HNLs, taking into account the new decay channel. Although the constraints are typically weakened, in some cases they can become stronger, due to observable $s\to\ell^+\ell^-$ decays in the detectors. The method presented here could be used to recast constraints from other (older) experiments without resorting to computationally expensive Monte Carlo simulations. In addition, we update and correct some errors in the analysis of the original constraints, in the absence of the singlet. |
hep-ph/9712320 | Cheuk-Yin Wong | Cheuk-Yin Wong (ORNL) | Heavy Quarkonium Production and Propagation in Nuclei | 8 pages (REVTeX), to be published in the Proceedings of International
Symposium on Trends in Subatomic Physics, August 7-12, 1997, Taipei | Chin.J.Phys.35:857-865,1997 | null | ORNL-CTP-9703 | hep-ph | null | We describe a precursor in heavy quarkonium production in terms of a coherent
admixture of states of different color, spin, and angular momentum quantum
numbers, and obtain the production amplitudes for different quarkonium bound
states by projecting out this precursor state onto these bound states. The
precursor is absorbed in its passage through a nucleus in a pA reaction, and
the total cross section between this precursor with a nucleon can be calculated
with the two-gluon model of the Pomeron. Such a description of coherent
precursors and their subsequent interactions with nucleons can explain many
salient features of J/psi and psi' production in pA collisions.
| [
{
"created": "Tue, 9 Dec 1997 20:27:00 GMT",
"version": "v1"
}
] | 2011-04-15 | [
[
"Wong",
"Cheuk-Yin",
"",
"ORNL"
]
] | We describe a precursor in heavy quarkonium production in terms of a coherent admixture of states of different color, spin, and angular momentum quantum numbers, and obtain the production amplitudes for different quarkonium bound states by projecting out this precursor state onto these bound states. The precursor is absorbed in its passage through a nucleus in a pA reaction, and the total cross section between this precursor with a nucleon can be calculated with the two-gluon model of the Pomeron. Such a description of coherent precursors and their subsequent interactions with nucleons can explain many salient features of J/psi and psi' production in pA collisions. |
1003.4677 | C. Anastasiou | Charalampos Anastasiou, Radja Boughezal, Elisabetta Furlan | The NNLO gluon fusion Higgs production cross-section with many heavy
quarks | 14 pages, 1 table | JHEP 1006:101,2010 | 10.1007/JHEP06(2010)101 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider extensions of the Standard Model with a number of additional
heavy quarks which couple to the Higgs boson via top-like Yukawa interactions.
We construct an effective theory valid for a Higgs boson mass which is lighter
than twice the lightest heavy quark mass and compute the corresponding Wilson
coefficient through NNLO. We present numerical results for the gluon fusion
cross-section at the Tevatron for an extension of the Standard Model with a
fourth generation of heavy quarks. The gluon fusion cross-section is enhanced
by a factor of roughly 9 with respect to the Standard Model value. Tevatron
experimental data can place stringent exclusion limits for the Higgs mass in
this model.
| [
{
"created": "Wed, 24 Mar 2010 16:05:10 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Anastasiou",
"Charalampos",
""
],
[
"Boughezal",
"Radja",
""
],
[
"Furlan",
"Elisabetta",
""
]
] | We consider extensions of the Standard Model with a number of additional heavy quarks which couple to the Higgs boson via top-like Yukawa interactions. We construct an effective theory valid for a Higgs boson mass which is lighter than twice the lightest heavy quark mass and compute the corresponding Wilson coefficient through NNLO. We present numerical results for the gluon fusion cross-section at the Tevatron for an extension of the Standard Model with a fourth generation of heavy quarks. The gluon fusion cross-section is enhanced by a factor of roughly 9 with respect to the Standard Model value. Tevatron experimental data can place stringent exclusion limits for the Higgs mass in this model. |
1507.03428 | Shinya Matsuzaki | Hidenori S. Fukano, Shinya Matsuzaki and Koichi Yamawaki | Conformal Barrier for New Vector Bosons Decay to the Higgs | latex, 4 pages: some corrections made; version published in MPLA, 4
March 2016 | null | 10.1142/S0217732316300093 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The ATLAS collaboration has recently reported excesses about 2.5 sigma at
mass around 2 TeV in the diboson channels, which can be identified with new
vector bosons as a hint for the new physics. It is shown that spontaneously
broken conformal/scale symmetry prohibits new vector bosons decay to the Higgs,
which is contrasted to the popular "equivalence theorem" valid only in a
special limit not necessarily relevant to the 2 TeV mass. If the decay $V\to
WH/ZH$ is not observed in the ongoing Run II of the LHC, then the 125 GeV Higgs
can be a dilaton.
| [
{
"created": "Mon, 13 Jul 2015 12:43:18 GMT",
"version": "v1"
},
{
"created": "Sun, 19 Jul 2015 09:38:28 GMT",
"version": "v2"
},
{
"created": "Mon, 19 Oct 2015 12:02:32 GMT",
"version": "v3"
},
{
"created": "Thu, 24 Mar 2016 17:21:16 GMT",
"version": "v4"
}
] | 2016-03-25 | [
[
"Fukano",
"Hidenori S.",
""
],
[
"Matsuzaki",
"Shinya",
""
],
[
"Yamawaki",
"Koichi",
""
]
] | The ATLAS collaboration has recently reported excesses about 2.5 sigma at mass around 2 TeV in the diboson channels, which can be identified with new vector bosons as a hint for the new physics. It is shown that spontaneously broken conformal/scale symmetry prohibits new vector bosons decay to the Higgs, which is contrasted to the popular "equivalence theorem" valid only in a special limit not necessarily relevant to the 2 TeV mass. If the decay $V\to WH/ZH$ is not observed in the ongoing Run II of the LHC, then the 125 GeV Higgs can be a dilaton. |
2406.05123 | Abhishek Mohapatra | Fareed Alasiri, Eric Braaten, and Abhishek Mohapatra | Born-Oppenheimer Potentials for $SU(3)$ Gauge Theory | 37 pages, 10 figures, 4 tables | null | null | TUM-EFT 188/24 | hep-ph hep-lat | http://creativecommons.org/licenses/by/4.0/ | We develop parameterizations of 8 of the lowest Born-Oppenheimer potentials
for quarkonium hybrid mesons as functions of the separation $r$ of the static
quark and antiquark sources. The parameters are determined by fitting results
calculated using pure $SU(3)$ lattice gauge theory. The parameterizations have
the correct limiting behavior at small $r$, where the potentials form
multiplets associated with gluelumps. They have the correct limiting behavior
at large $r$, where the potentials form multiplets associated with excitations
of a relativistic string. There is a narrow avoided crossing in the small-$r$
region between two potentials with the same Born-Oppenheimer quantum numbers.
| [
{
"created": "Fri, 7 Jun 2024 17:53:37 GMT",
"version": "v1"
}
] | 2024-06-10 | [
[
"Alasiri",
"Fareed",
""
],
[
"Braaten",
"Eric",
""
],
[
"Mohapatra",
"Abhishek",
""
]
] | We develop parameterizations of 8 of the lowest Born-Oppenheimer potentials for quarkonium hybrid mesons as functions of the separation $r$ of the static quark and antiquark sources. The parameters are determined by fitting results calculated using pure $SU(3)$ lattice gauge theory. The parameterizations have the correct limiting behavior at small $r$, where the potentials form multiplets associated with gluelumps. They have the correct limiting behavior at large $r$, where the potentials form multiplets associated with excitations of a relativistic string. There is a narrow avoided crossing in the small-$r$ region between two potentials with the same Born-Oppenheimer quantum numbers. |
hep-ph/0701184 | Yacine Mehtar-Tani | Yacine Mehtar-Tani | Has saturation physics been observed in deuteron-gold collisions at
RHIC? | 4 pages, 2 figures. Talk given at 41st Rencontres de Moriond: QCD and
Hadronic Interactions, La Thuile, Italy, 18-25 Mar 2006 | null | null | LPT-ORSAY-06-96 | hep-ph | null | We have addressed the question of whether saturation (CGC) has been observed
in deuteron-gold collisions at RHIC. We have made a detailed analysis of the
Cronin peak characteristic of the nuclear modification factor measured for d-Au
collisions at mid-rapidity. The Cronin peak which is obtained around $p_t\simeq
3$ GeV may be reproduced at the proper height only by boosting the saturation
momentum by a huge non-perturbative additional component. At forward rapidity,
we get a quantitative agreement with data, reproducing hadron production
spectra and the $R_{CP}$ ratio using a recently developed description of the
small-x physics.
| [
{
"created": "Mon, 22 Jan 2007 18:01:36 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mehtar-Tani",
"Yacine",
""
]
] | We have addressed the question of whether saturation (CGC) has been observed in deuteron-gold collisions at RHIC. We have made a detailed analysis of the Cronin peak characteristic of the nuclear modification factor measured for d-Au collisions at mid-rapidity. The Cronin peak which is obtained around $p_t\simeq 3$ GeV may be reproduced at the proper height only by boosting the saturation momentum by a huge non-perturbative additional component. At forward rapidity, we get a quantitative agreement with data, reproducing hadron production spectra and the $R_{CP}$ ratio using a recently developed description of the small-x physics. |
1709.04993 | Dennis Perepelitsa | Massimiliano Alvioli, Leonid Frankfurt, Dennis Perepelitsa, Mark
Strikman | Global analysis of color fluctuation effects in proton- and
deuteron-nucleus collisions at RHIC and the LHC | 7 pages, 4 figures; Accepted for publication by Phys. Rev. D (Rapid
Communications) | Phys. Rev. D 98, 071502 (2018) | 10.1103/PhysRevD.98.071502 | null | hep-ph hep-ex nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We test the hypothesis that configurations of a proton with a large-$x$
parton, $x_p \gtrsim 0.1$, have a smaller than average size. The QCD $Q^2$
evolution equations suggest that these small configurations also have a
significantly smaller interaction strength, which has observable consequences
in collisions with nuclei. We perform a global analysis of jet production data
in proton- and deuteron-nucleus collisions at RHIC and the LHC. Using a model
which takes a distribution of interaction strengths into account, we
quantitatively extract the $x_p$-dependence of the average interaction
strength, $\sigma(x_p)$, over a wide kinematic range. By comparing the RHIC and
LHC results, our analysis finds that the interaction strength for small
configurations, while suppressed, grows faster with collision energy than does
that for average configurations. We check that this energy dependence is
consistent with the results of a method which, given $\sigma(x_p)$ at one
energy, can be used to quantitatively predict that at another. This finding
further suggests that at even lower energies, nucleons with a large-$x_p$
parton should interact much more weakly than those in an average configuration,
a phenomenon in line with explanations of the EMC effect for large-$x_p$ quarks
in nuclei based on color screening.
| [
{
"created": "Thu, 14 Sep 2017 22:05:23 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Sep 2018 10:27:56 GMT",
"version": "v2"
}
] | 2018-10-17 | [
[
"Alvioli",
"Massimiliano",
""
],
[
"Frankfurt",
"Leonid",
""
],
[
"Perepelitsa",
"Dennis",
""
],
[
"Strikman",
"Mark",
""
]
] | We test the hypothesis that configurations of a proton with a large-$x$ parton, $x_p \gtrsim 0.1$, have a smaller than average size. The QCD $Q^2$ evolution equations suggest that these small configurations also have a significantly smaller interaction strength, which has observable consequences in collisions with nuclei. We perform a global analysis of jet production data in proton- and deuteron-nucleus collisions at RHIC and the LHC. Using a model which takes a distribution of interaction strengths into account, we quantitatively extract the $x_p$-dependence of the average interaction strength, $\sigma(x_p)$, over a wide kinematic range. By comparing the RHIC and LHC results, our analysis finds that the interaction strength for small configurations, while suppressed, grows faster with collision energy than does that for average configurations. We check that this energy dependence is consistent with the results of a method which, given $\sigma(x_p)$ at one energy, can be used to quantitatively predict that at another. This finding further suggests that at even lower energies, nucleons with a large-$x_p$ parton should interact much more weakly than those in an average configuration, a phenomenon in line with explanations of the EMC effect for large-$x_p$ quarks in nuclei based on color screening. |
1207.1014 | K. S. Babu | A. Albaid, K.S. Babu | Higgs boson of mass 125 GeV in GMSB models with messenger-matter mixing | 31 pages, LaTeX | null | 10.1103/PhysRevD.88.055007 | OSU-HEP-12-07 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the effects of messenger-matter mixing on the lightest CP-even
Higgs boson mass m_h in gauge-mediated supersymmetry breaking models. It is
shown that with such mixings m_h can be raised to about 125 GeV, even when the
superparticles have sub-TeV masses, and when the gravitino has a cosmologically
preferred sub-keV mass. In minimal gauge mediation without messenger-matter
mixing, realizing m_h = 125 GeV would require multi-TeV SUSY spectrum. The
increase in $m_h$ due to messenger-matter mixing is maximal in the case of
messengers belonging to 10+\bar{10} of SU(5) unification, while it is still
significant when they belong to $5+\bar{5}$ of SU(5). Our results are
compatible with gauge coupling unification, perturbativity, and the unification
of messenger Yukawa couplings. We embed these models into a grand unification
framework with a U(1) flavor symmetry that addresses the fermion mass hierarchy
and generates naturally large neutrino mixing angles. While SUSY mediated
flavor changing processes are sufficiently suppressed in such an embedding,
small new contributions to K^0-\bar{K^0} mixing can resolve the apparent
discrepancy in the CP asymmetry parameters \sin2\beta and \epsilon_K.
| [
{
"created": "Wed, 4 Jul 2012 15:06:05 GMT",
"version": "v1"
}
] | 2013-09-11 | [
[
"Albaid",
"A.",
""
],
[
"Babu",
"K. S.",
""
]
] | We investigate the effects of messenger-matter mixing on the lightest CP-even Higgs boson mass m_h in gauge-mediated supersymmetry breaking models. It is shown that with such mixings m_h can be raised to about 125 GeV, even when the superparticles have sub-TeV masses, and when the gravitino has a cosmologically preferred sub-keV mass. In minimal gauge mediation without messenger-matter mixing, realizing m_h = 125 GeV would require multi-TeV SUSY spectrum. The increase in $m_h$ due to messenger-matter mixing is maximal in the case of messengers belonging to 10+\bar{10} of SU(5) unification, while it is still significant when they belong to $5+\bar{5}$ of SU(5). Our results are compatible with gauge coupling unification, perturbativity, and the unification of messenger Yukawa couplings. We embed these models into a grand unification framework with a U(1) flavor symmetry that addresses the fermion mass hierarchy and generates naturally large neutrino mixing angles. While SUSY mediated flavor changing processes are sufficiently suppressed in such an embedding, small new contributions to K^0-\bar{K^0} mixing can resolve the apparent discrepancy in the CP asymmetry parameters \sin2\beta and \epsilon_K. |
hep-ph/9907457 | Hyun-Chul Kim | Mario Franz, Hyun-Chul Kim, and Klaus Goeke | Effective Weak Chiral Lagrangian from the Instanton Vacuum | 4 pages, espcrc1 is used. Talk given at PANIC `99, Uppsala Sweden,
June 10, 1999 | Nucl.Phys. A663 (2000) 995-998 | 10.1016/S0375-9474(99)00752-6 | PNU-NTG-03/99, RUB-TPII-10/99 | hep-ph | null | We present in this talk the recent investigation of the effective weak chiral
Lagrangian within the framework of the instanton-induced chiral quark model.
The low energy constants in leading order $g_8$ and $g_{27}$, and their ratio
are determined. The momentum-dependence of the constituent quark mass turns out
to improve the low energy constants to the great extent, respecting the $\Delta
T=1/2$ enhancement.
| [
{
"created": "Thu, 22 Jul 1999 13:03:48 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Franz",
"Mario",
""
],
[
"Kim",
"Hyun-Chul",
""
],
[
"Goeke",
"Klaus",
""
]
] | We present in this talk the recent investigation of the effective weak chiral Lagrangian within the framework of the instanton-induced chiral quark model. The low energy constants in leading order $g_8$ and $g_{27}$, and their ratio are determined. The momentum-dependence of the constituent quark mass turns out to improve the low energy constants to the great extent, respecting the $\Delta T=1/2$ enhancement. |
1405.4762 | Christian Fischer | Christian S. Fischer, Jan Luecker and Christian A. Welzbacher | Phase structure of three and four flavor QCD | 10 pages, 9 figures, v2: typos corrected, minor changes, version
accepted by PRD | Phys. Rev. D 90, 034022 (2014) | 10.1103/PhysRevD.90.034022 | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the phase structure of QCD at finite temperature and
light-quark chemical potential. We improve upon earlier results for N_f=2+1
dynamical quark flavors and investigate the effects of charm quarks in an
extension to N_f=2+1+1. We determine the quark condensate and the Polyakov loop
potential using solutions of a coupled set of (truncated) Dyson-Schwinger
equations for the quark and gluon propagators of Landau gauge QCD. At zero
chemical potential we find excellent agreement with results from lattice-QCD.
With input fixed from physical observables we find only a very small influence
of the charm quark on the resulting phase diagram at finite chemical potential.
We discuss the location of the emerging critical end-point and compare with
expectations from lattice gauge theory.
| [
{
"created": "Mon, 19 May 2014 15:20:44 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Aug 2014 15:18:58 GMT",
"version": "v2"
}
] | 2014-09-05 | [
[
"Fischer",
"Christian S.",
""
],
[
"Luecker",
"Jan",
""
],
[
"Welzbacher",
"Christian A.",
""
]
] | We investigate the phase structure of QCD at finite temperature and light-quark chemical potential. We improve upon earlier results for N_f=2+1 dynamical quark flavors and investigate the effects of charm quarks in an extension to N_f=2+1+1. We determine the quark condensate and the Polyakov loop potential using solutions of a coupled set of (truncated) Dyson-Schwinger equations for the quark and gluon propagators of Landau gauge QCD. At zero chemical potential we find excellent agreement with results from lattice-QCD. With input fixed from physical observables we find only a very small influence of the charm quark on the resulting phase diagram at finite chemical potential. We discuss the location of the emerging critical end-point and compare with expectations from lattice gauge theory. |
1207.5522 | Daniele Alves | Daniele S. M. Alves, Patrick J. Fox and Neal Weiner | Supersymmetry with a Sister Higgs | 36 pages | Phys. Rev. D 91, 055003 (2015) | 10.1103/PhysRevD.91.055003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Within the context of supersymmetric theories, explaining a 125 GeV Higgs
motivates a consideration of a broader range of models. We consider a simple
addition to the MSSM of a "Sister Higgs" ($\Sigma_d$), a Higgs field that
participates in electroweak symmetry breaking but does not give any direct
masses to Standard Model matter fields. While a relatively minor addition, the
phenomenological implications can be important. Such a field can be naturally
charged under an additional symmetry group $G_s$. If gauged, the Higgs mass is
naturally much larger than in the MSSM through an NMSSM-type interaction, but
with $\Sigma_d$ playing the role of $H_d$. The addition of the sister Higgs
allows new R-parity violating operators $\Sigma_d H_d E$, which are less
constrained than conventional leptonic R-parity violation. Considerations of
unification motivates the presence of colored $G_s$-charged fields. Production
of these G-quarks can lead to new b-rich final states and modifications to
decays of gluinos, as well as new opportunities for R-parity violation. Unlike
a conventional fourth generation, G-quarks dominantly decay into a light jet
and a scalar (potentially the Higgs), which then generally decays to b-jets.
The presence of additional sister charges allows the possibilities that
lightest sister-charged particle (LSiP) could be stable. We consider the
possibility of an LSiP dark matter candidate and find it is generally very
constrained.
| [
{
"created": "Mon, 23 Jul 2012 20:10:18 GMT",
"version": "v1"
}
] | 2015-03-11 | [
[
"Alves",
"Daniele S. M.",
""
],
[
"Fox",
"Patrick J.",
""
],
[
"Weiner",
"Neal",
""
]
] | Within the context of supersymmetric theories, explaining a 125 GeV Higgs motivates a consideration of a broader range of models. We consider a simple addition to the MSSM of a "Sister Higgs" ($\Sigma_d$), a Higgs field that participates in electroweak symmetry breaking but does not give any direct masses to Standard Model matter fields. While a relatively minor addition, the phenomenological implications can be important. Such a field can be naturally charged under an additional symmetry group $G_s$. If gauged, the Higgs mass is naturally much larger than in the MSSM through an NMSSM-type interaction, but with $\Sigma_d$ playing the role of $H_d$. The addition of the sister Higgs allows new R-parity violating operators $\Sigma_d H_d E$, which are less constrained than conventional leptonic R-parity violation. Considerations of unification motivates the presence of colored $G_s$-charged fields. Production of these G-quarks can lead to new b-rich final states and modifications to decays of gluinos, as well as new opportunities for R-parity violation. Unlike a conventional fourth generation, G-quarks dominantly decay into a light jet and a scalar (potentially the Higgs), which then generally decays to b-jets. The presence of additional sister charges allows the possibilities that lightest sister-charged particle (LSiP) could be stable. We consider the possibility of an LSiP dark matter candidate and find it is generally very constrained. |
hep-ph/9407238 | Peter Sieber | Dmitri Diakonov, Maxim Polyakov, Pavel Pobylitsa, Peter Sieber, Joerg
Schaldach, Klaus Goeke | Loop corrections to the sphaleron transition rate in the minimal
standard model | 11 pages (LaTex) plus 2 figures (uuencoded postscript files);
RUB-TPII-05/94 | Phys.Lett.B336:457-463,1994 | 10.1016/0370-2693(94)90558-4 | null | hep-ph | null | The baryon number dissipation rate due to sphaleron transitions at high
temperatures in the minimal standard model is evaluated. We find that this rate
can be considerably suppressed by one loop contributions of bosonic and
fermionic fluctuations which are particularly important for a small mass of the
Higgs boson and a large top quark mass. Fixing the latter to its recently
stated value of 174 GeV the complete erasure of the baryon asymmetry is
prevented within the framework of the minimal standard model if the Higgs mass
is less than about 66 GeV.
| [
{
"created": "Wed, 6 Jul 1994 13:11:24 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Diakonov",
"Dmitri",
""
],
[
"Polyakov",
"Maxim",
""
],
[
"Pobylitsa",
"Pavel",
""
],
[
"Sieber",
"Peter",
""
],
[
"Schaldach",
"Joerg",
""
],
[
"Goeke",
"Klaus",
""
]
] | The baryon number dissipation rate due to sphaleron transitions at high temperatures in the minimal standard model is evaluated. We find that this rate can be considerably suppressed by one loop contributions of bosonic and fermionic fluctuations which are particularly important for a small mass of the Higgs boson and a large top quark mass. Fixing the latter to its recently stated value of 174 GeV the complete erasure of the baryon asymmetry is prevented within the framework of the minimal standard model if the Higgs mass is less than about 66 GeV. |
2203.00024 | Federica Pompa | Federica Pompa, Francesco Capozzi, Olga Mena, Michel Sorel | An absolute $\nu$ mass measurement with the DUNE experiment | 5 pages, 3 figures. Version accepted for publication in Phys. Rev.
Lett | Phys. Rev. Lett. 129, 121802 (2022) | 10.1103/PhysRevLett.129.121802 | null | hep-ph astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | Time of flight delay in the supernova neutrino signal offers a unique tool to
set model-independent constraints on the absolute neutrino mass. The presence
of a sharp time structure during a first emission phase, the so-called
neutronization burst in the electron neutrino flavor time distribution, makes
this channel a very powerful one. Large liquid argon underground detectors will
provide precision measurements of the time dependence of the electron neutrino
fluxes. We derive here a new $\nu$ mass sensitivity attainable at the future
DUNE far detector from a future supernova collapse in our galactic
neighborhood, finding a sub-eV reach under favorable scenarios. These values
are competitive with those expected for laboratory direct neutrino mass
searches.
| [
{
"created": "Mon, 28 Feb 2022 19:00:06 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Sep 2022 14:41:12 GMT",
"version": "v2"
}
] | 2022-09-15 | [
[
"Pompa",
"Federica",
""
],
[
"Capozzi",
"Francesco",
""
],
[
"Mena",
"Olga",
""
],
[
"Sorel",
"Michel",
""
]
] | Time of flight delay in the supernova neutrino signal offers a unique tool to set model-independent constraints on the absolute neutrino mass. The presence of a sharp time structure during a first emission phase, the so-called neutronization burst in the electron neutrino flavor time distribution, makes this channel a very powerful one. Large liquid argon underground detectors will provide precision measurements of the time dependence of the electron neutrino fluxes. We derive here a new $\nu$ mass sensitivity attainable at the future DUNE far detector from a future supernova collapse in our galactic neighborhood, finding a sub-eV reach under favorable scenarios. These values are competitive with those expected for laboratory direct neutrino mass searches. |
hep-ph/0512084 | Ayres Freitas | G. A. Blair, A. Freitas, H.-U. Martyn, G. Polesello, W. Porod, P. M.
Zerwas | Reconstructing Supersymmetry at ILC/LHC | published in Proceedings of the Ustron Conference 2005; technical
LaTeX problem corrected | Acta Phys.Polon. B36 (2005) 3445-3462 | null | DESY 05-240, IFIC/05-64, ZH-TH 25/05 | hep-ph | null | Coherent analyses of experimental results from LHC and ILC will allow us to
draw a comprehensive and precise picture of the supersymmetric particle sector.
Based on this platform the fundamental supersymmetric theory can be
reconstructed at the high scale which is potentially close to the Planck scale.
This procedure will be reviewed for three characteristic examples: minimal
supergravity as the paradigm; a left-right symmetric extension incorporating
intermediate mass scales; and a specific realization of string effective
theories.
| [
{
"created": "Wed, 7 Dec 2005 09:57:28 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Dec 2005 14:31:45 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Blair",
"G. A.",
""
],
[
"Freitas",
"A.",
""
],
[
"Martyn",
"H. -U.",
""
],
[
"Polesello",
"G.",
""
],
[
"Porod",
"W.",
""
],
[
"Zerwas",
"P. M.",
""
]
] | Coherent analyses of experimental results from LHC and ILC will allow us to draw a comprehensive and precise picture of the supersymmetric particle sector. Based on this platform the fundamental supersymmetric theory can be reconstructed at the high scale which is potentially close to the Planck scale. This procedure will be reviewed for three characteristic examples: minimal supergravity as the paradigm; a left-right symmetric extension incorporating intermediate mass scales; and a specific realization of string effective theories. |
0709.3744 | Martin W. Gruenewald | Martin W. Grunewald | Combined Electroweak Analysis | 7 pages and 6 figures | J.Phys.Conf.Ser.110:042008,2008 | 10.1088/1742-6596/110/4/042008 | UCD-PHYC/070901 | hep-ph hep-ex | null | Recent developments in the measurement of precision electroweak measurements
are summarised, notably new results on the mass of the top quark and mass and
width of the W boson. Predictions of the Standard Model are compared to the
experimental results which are used to constrain the input parameters of the
Standard Model, in particular the mass of the Higgs boson. The agreement
between measurements and expectations from theory is discussed.
Invited talk presented at the EPS HEP 2007 conference
Manchester, England, July 19th to 25th, 2007
| [
{
"created": "Mon, 24 Sep 2007 13:31:13 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Grunewald",
"Martin W.",
""
]
] | Recent developments in the measurement of precision electroweak measurements are summarised, notably new results on the mass of the top quark and mass and width of the W boson. Predictions of the Standard Model are compared to the experimental results which are used to constrain the input parameters of the Standard Model, in particular the mass of the Higgs boson. The agreement between measurements and expectations from theory is discussed. Invited talk presented at the EPS HEP 2007 conference Manchester, England, July 19th to 25th, 2007 |
0909.4527 | Alexander Bakulev P. | Alexander P. Bakulev | Pion form factor in QCD sum rules, local duality approach, and O(A_2)
fractional analytic perturbation theory | 4 pages, 2 figures, invited talk at the 3rd Joint International
Hadron Structure'09 Conference, Tatranska Strba (Slovak Republic), Aug.
30--Sept. 3, 2009 | Nucl.Phys.Proc.Suppl.198:204-207,2010 | 10.1016/j.nuclphysbps.2009.12.040 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the results on the electromagnetic pion Form Factor (FF) obtained in
the $O(\alpha_s)$ QCD sum rules with non-local condensates \cite{BPS09} we
determine the effective continuum threshold for the local duality approach.
Then we apply it to construct the $O(\alpha_s^2)$ estimation of the pion FF in
the framework of the fractional analytic perturbation theory.
| [
{
"created": "Thu, 24 Sep 2009 19:41:12 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Sep 2009 21:34:45 GMT",
"version": "v2"
}
] | 2010-04-22 | [
[
"Bakulev",
"Alexander P.",
""
]
] | Using the results on the electromagnetic pion Form Factor (FF) obtained in the $O(\alpha_s)$ QCD sum rules with non-local condensates \cite{BPS09} we determine the effective continuum threshold for the local duality approach. Then we apply it to construct the $O(\alpha_s^2)$ estimation of the pion FF in the framework of the fractional analytic perturbation theory. |
hep-ph/0008158 | null | R. N. Mohapatra, A. Perez-Lorenzana and C. A. de S. Pires | Neutrino mass, bulk majoron and neutrinoless double beta decay | 7 pages, one figure embedded; UMD-PP-00-099 | Phys.Lett.B491:143-147,2000 | 10.1016/S0370-2693(00)01031-5 | null | hep-ph | null | A new economical model for neutrino masses is proposed in the context of
brane bulk scenarios for particle physics, where global B-L symmetry of the
standard model is broken spontaneously by a gauge singlet Higgs field in the
bulk. This leads to a bulk majoron whose KK excitations may make it visible if
neutrinoless double beta decay if the string scale is close to a TeV. It also
leads to neutron-anti-neutron oscillation process with transition times which
can be in the range accessible to proposed experiments.
| [
{
"created": "Tue, 15 Aug 2000 20:14:23 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Mohapatra",
"R. N.",
""
],
[
"Perez-Lorenzana",
"A.",
""
],
[
"Pires",
"C. A. de S.",
""
]
] | A new economical model for neutrino masses is proposed in the context of brane bulk scenarios for particle physics, where global B-L symmetry of the standard model is broken spontaneously by a gauge singlet Higgs field in the bulk. This leads to a bulk majoron whose KK excitations may make it visible if neutrinoless double beta decay if the string scale is close to a TeV. It also leads to neutron-anti-neutron oscillation process with transition times which can be in the range accessible to proposed experiments. |
0710.1790 | Jose Maria Verde-Velasco | J.M. Verde-Velasco | Static and dynamic properties of hadronic systems with heavy quarks b
and c | PhD thesis, Supervisors: E. Hernandez, J. Nieves 183 pages | null | null | null | hep-ph | null | This thesis has been devoted to the study of different properties of hadrons
with one and two heavy quarks $c$ and/or $b$. All calculations have been done
in the framework of a nonrelativistic constituent quark model. In order to
check the sensitivity of our results to the inter--quark interaction we have
used five different quark--quark potentials. The spread in results gives an
estimation of theoretical uncertainties and so has been quoted.
Most observables studied change only at the level of a few per cent when
changing the interaction potential.
Another source of theoretical uncertainty is the use of nonrelativistic
kinematics in the evaluation of the orbital wave functions and the construction
of our nonrelativistic states, although we think that a good part of these
relativistic effects are contained in an effective way in the parameters of the
quark-quark potentials, which were adjusted in the original works to reproduce
the experimental spectra of mesons. Mesons wave functions have been evaluated
using a Numerov algorithm, while for baryons the three body problem has been
solved using a variational approach with ansatz wave functions that include
simplifications that arise from HQS and HQSS. To compute hadron decays we have
relied on the impulse approximation, which induces small axial and vector
current conservation violations due to binding effects. These binding effects,
though they affect some of the weak form factors analyzed, have little
influence on the decay widths.
| [
{
"created": "Tue, 9 Oct 2007 15:20:08 GMT",
"version": "v1"
}
] | 2007-10-10 | [
[
"Verde-Velasco",
"J. M.",
""
]
] | This thesis has been devoted to the study of different properties of hadrons with one and two heavy quarks $c$ and/or $b$. All calculations have been done in the framework of a nonrelativistic constituent quark model. In order to check the sensitivity of our results to the inter--quark interaction we have used five different quark--quark potentials. The spread in results gives an estimation of theoretical uncertainties and so has been quoted. Most observables studied change only at the level of a few per cent when changing the interaction potential. Another source of theoretical uncertainty is the use of nonrelativistic kinematics in the evaluation of the orbital wave functions and the construction of our nonrelativistic states, although we think that a good part of these relativistic effects are contained in an effective way in the parameters of the quark-quark potentials, which were adjusted in the original works to reproduce the experimental spectra of mesons. Mesons wave functions have been evaluated using a Numerov algorithm, while for baryons the three body problem has been solved using a variational approach with ansatz wave functions that include simplifications that arise from HQS and HQSS. To compute hadron decays we have relied on the impulse approximation, which induces small axial and vector current conservation violations due to binding effects. These binding effects, though they affect some of the weak form factors analyzed, have little influence on the decay widths. |
1109.0995 | Jihn E. Kim | Jihn E. Kim | The CKM matrix with maximal CP violation from Z(12) symmetry | 7 pages of LaTeX file. No figure | null | 10.1016/j.physletb.2011.09.042 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recent accurate determination of the CKM parameters including the maximal
CP phase 90 degrees enables us to write down the up-type and down-type quark
mass matrices to a high degree of accuracy. The lightest element(the uu
element) of the quark mass texture (not the mass eigenvalue) has a power
lambda**6 where lambda=sin(Cabibbo angle). The CP phase of 360 degrees divided
by an integer hints a discrete symmetry. Since lambda**6 is the highest power
among the quark mass matrix elements, we present as an example a possibility
that the maximal CP phase 90 degrees is obtainable from a supersymmetric Z(12)
discrete symmetry model.
| [
{
"created": "Mon, 5 Sep 2011 20:00:04 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Kim",
"Jihn E.",
""
]
] | The recent accurate determination of the CKM parameters including the maximal CP phase 90 degrees enables us to write down the up-type and down-type quark mass matrices to a high degree of accuracy. The lightest element(the uu element) of the quark mass texture (not the mass eigenvalue) has a power lambda**6 where lambda=sin(Cabibbo angle). The CP phase of 360 degrees divided by an integer hints a discrete symmetry. Since lambda**6 is the highest power among the quark mass matrix elements, we present as an example a possibility that the maximal CP phase 90 degrees is obtainable from a supersymmetric Z(12) discrete symmetry model. |
hep-ph/0008331 | Charanjit Singh Aulakh | Charanjit S. Aulakh | Supersymmetric Unification at the Millenium | Plenary Talk at WHEPP-6, Chennai, India, Jan. 3-15, 2000. ReVTeX. 9
pages. Two pairs of figures as separate postscript file | Pramana 55:137-149,2000 | 10.1007/s12043-000-0090-5 | null | hep-ph | null | We argue that the discovery of neutrino mass effects at Super-Kamiokande
implies a clear logical chain leading from the Standard Model, through the MSSM
and the recently developed Minimal Left Right Supersymmetric models with a
renormalizable see-saw mechanism for neutrino mass, to Left Right symmetric
SUSY GUTS : in particular, SO(10) and $SU(2)_L \times SU(2)_R\times SU(4)_c$.
The progress in constructing such GUTS explicitly is reviewed and their
testability/falsifiability by lepton flavour violation and proton decay
measurements emphasized. Susy violations of the survival principle and the
interplay between third generation Yukawa coupling unification and the
structurally stable IR attractive features of the RG flow in SUSY GUTS are also
discussed .
| [
{
"created": "Thu, 31 Aug 2000 13:30:16 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Aulakh",
"Charanjit S.",
""
]
] | We argue that the discovery of neutrino mass effects at Super-Kamiokande implies a clear logical chain leading from the Standard Model, through the MSSM and the recently developed Minimal Left Right Supersymmetric models with a renormalizable see-saw mechanism for neutrino mass, to Left Right symmetric SUSY GUTS : in particular, SO(10) and $SU(2)_L \times SU(2)_R\times SU(4)_c$. The progress in constructing such GUTS explicitly is reviewed and their testability/falsifiability by lepton flavour violation and proton decay measurements emphasized. Susy violations of the survival principle and the interplay between third generation Yukawa coupling unification and the structurally stable IR attractive features of the RG flow in SUSY GUTS are also discussed . |
1803.08880 | Matteo Fael | Matteo Fael and Thomas Mannel | On the decays $B \to K^{(*)} + $ leptonium | 17 pages | null | 10.1016/j.nuclphysb.2018.05.015 | SI-HEP-2018-12, QFET-2018-06 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We determine the rates of the $B$ meson decays into a $K^{(*)}$ and an
$\ell^+ \ell^-$ bound state, the leptonium, where $\ell = e,\mu,\tau$. The two
spin states of the leptonium, the spin singlet and the spin triplet, couple to
the axial current and to the vector current, respectively, thus probing
different helicity structures of the underlying $b\to s \ell^+\ell^-$ effective
Hamiltonian. Since ortho- and para-leptonia have different decay modes, a
distinction between the two is relatively easy and these decays may become a
cross check for the results of lepton-flavour-violation searches obtained with
free leptons. We find that some of the decays involving muon and tau have a
branching ratio of the order of $10^{-13}$ and they may become accessible at
the LHCb with 50 fb$^{-1}$ of integrated luminosity. In addition, since the
tau-pair threshold lies right between the $J/\psi$ and the $\psi(2S)$
resonances, we estimate the charm-loop contribution to the decays $B \to
K^{(*)} + $tauonium.
| [
{
"created": "Fri, 23 Mar 2018 16:54:49 GMT",
"version": "v1"
}
] | 2018-05-30 | [
[
"Fael",
"Matteo",
""
],
[
"Mannel",
"Thomas",
""
]
] | We determine the rates of the $B$ meson decays into a $K^{(*)}$ and an $\ell^+ \ell^-$ bound state, the leptonium, where $\ell = e,\mu,\tau$. The two spin states of the leptonium, the spin singlet and the spin triplet, couple to the axial current and to the vector current, respectively, thus probing different helicity structures of the underlying $b\to s \ell^+\ell^-$ effective Hamiltonian. Since ortho- and para-leptonia have different decay modes, a distinction between the two is relatively easy and these decays may become a cross check for the results of lepton-flavour-violation searches obtained with free leptons. We find that some of the decays involving muon and tau have a branching ratio of the order of $10^{-13}$ and they may become accessible at the LHCb with 50 fb$^{-1}$ of integrated luminosity. In addition, since the tau-pair threshold lies right between the $J/\psi$ and the $\psi(2S)$ resonances, we estimate the charm-loop contribution to the decays $B \to K^{(*)} + $tauonium. |
hep-ph/9609401 | Alejandro Gangui | Brandon Carter, Patrick Peter and Alejandro Gangui | Avoidance of Collapse by Circular Current-Carrying Cosmic String Loops | 15 pp RevTeX plus 6 PostScript figures | Phys.Rev. D55 (1997) 4647-4662 | 10.1103/PhysRevD.55.4647 | null | hep-ph astro-ph gr-qc hep-th | null | Earlier attempts to calculate the nonlinear dynamical evolution of Witten
type superconducting vacuum vortex defects relied on the use of approximate
conducting string models that were too simple to take proper account of the
effect of current saturation. This effect is however allowed for adequately in
a newly developed class of rather more complicated, though still conveniently
analytic, conducting string models. These more realistic models have recently
been employed by Larsen and Axenides for investigating the collapse of circular
string loops in the case for which angular momentum is absent. The present work
extends this investigation to the generic case of circular string loops for
which angular momentum is present, so that there will be a centrifugal
potential barrier. This barrier will prevent collapse unless the initial
conditions are such that the relevant current saturation limit is attained, in
which case the string description of the vortex defect will break down, so that
its subsequent fate is hard to foresee. On the other hand if saturation is
avoided one would expect that the loop will eventually radiate away its excess
energy and settle down into a vorton type equilibrium state.
| [
{
"created": "Wed, 18 Sep 1996 18:05:59 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Carter",
"Brandon",
""
],
[
"Peter",
"Patrick",
""
],
[
"Gangui",
"Alejandro",
""
]
] | Earlier attempts to calculate the nonlinear dynamical evolution of Witten type superconducting vacuum vortex defects relied on the use of approximate conducting string models that were too simple to take proper account of the effect of current saturation. This effect is however allowed for adequately in a newly developed class of rather more complicated, though still conveniently analytic, conducting string models. These more realistic models have recently been employed by Larsen and Axenides for investigating the collapse of circular string loops in the case for which angular momentum is absent. The present work extends this investigation to the generic case of circular string loops for which angular momentum is present, so that there will be a centrifugal potential barrier. This barrier will prevent collapse unless the initial conditions are such that the relevant current saturation limit is attained, in which case the string description of the vortex defect will break down, so that its subsequent fate is hard to foresee. On the other hand if saturation is avoided one would expect that the loop will eventually radiate away its excess energy and settle down into a vorton type equilibrium state. |
hep-ph/0606303 | Bruno Machet | Quentin Duret (LPTHE), Bruno Machet (LPTHE) | Mixing Angles and Non-Degenerate Systems of Particles | 1 sentence added in the abstract | Phys.Lett.B643:303-310,2006 | 10.1016/j.physletb.2006.09.030 | null | hep-ph hep-th | null | Defining, in the framework of quantum field theory, their mass eigenstates
through their matricial propagator, we show why the mixing matrices of
non-degenerate coupled systems should not be parametrized as unitary. This is
how, for leptonic binary systems, two-angles solutions with discrete values
pi/4 [pi/2] and pi/2 [pi] (in addition to the trivial case 0 [pi]) arise when
weak leptonic currents of mass eigenstates approximately satisfy the two
properties of universality and vanishing of their non-diagonal neutral
components. Charged weak currents are also discussed, which leads to a few
remarks concerning oscillations. We argue that quarks, which cannot be defined
on shell because of the confinement property, are instead more naturally
endowed with unitary Cabibbo-like mixing matrices, involving a single
unconstrained mixing angle. The similarity between neutrinos and neutral kaons
is outlined, together with the role of the symmetry by exchange of families.
| [
{
"created": "Thu, 29 Jun 2006 14:42:54 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Sep 2006 08:43:18 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Duret",
"Quentin",
"",
"LPTHE"
],
[
"Machet",
"Bruno",
"",
"LPTHE"
]
] | Defining, in the framework of quantum field theory, their mass eigenstates through their matricial propagator, we show why the mixing matrices of non-degenerate coupled systems should not be parametrized as unitary. This is how, for leptonic binary systems, two-angles solutions with discrete values pi/4 [pi/2] and pi/2 [pi] (in addition to the trivial case 0 [pi]) arise when weak leptonic currents of mass eigenstates approximately satisfy the two properties of universality and vanishing of their non-diagonal neutral components. Charged weak currents are also discussed, which leads to a few remarks concerning oscillations. We argue that quarks, which cannot be defined on shell because of the confinement property, are instead more naturally endowed with unitary Cabibbo-like mixing matrices, involving a single unconstrained mixing angle. The similarity between neutrinos and neutral kaons is outlined, together with the role of the symmetry by exchange of families. |
1503.05041 | Amir Fariborz | Amir H. Fariborz, Azizollah Azizi, Abdorreza Asrar | Probing the substructure of $f_0(1370)$ | 20 pages, 11 figures | null | 10.1103/PhysRevD.91.073013 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Within an effective nonlinear chiral Lagrangian framework the substructure of
$f_0(1370)$ is studied. The investigation is conducted in the context of a
global picture of scalar mesons in which the importance of the underlying
connections among scalar mesons below and above 1 GeV is recognized and
implemented. These connections are due to the mixings among various
quark-antiquarks, four-quarks and glue components and play a central role in
understanding the properties of scalar mesons. Iterative Monte Carlo
simulations are first performed on the 14-dimensional parameter space of the
model and sets of points in this parameter space (the global sets) that give an
overall agreement with all experimental data on mass spectrum, various decay
widths and decay ratios of all isosinglet scalar states below 2 GeV are
determined. Then within each global set, subsets that give closest agreement
for the properties of $f_0(1370)$ are studied. Unlike the properties of other
isosinglet states that show a range of variation within each global set, it is
found that there is a clear signal for $f_0(1370)$ to be predominantly a
quark-antiquark state with a substantial $s {\bar s}$ component, together with
small remnants of four-quark and glue components.
| [
{
"created": "Tue, 17 Mar 2015 13:40:44 GMT",
"version": "v1"
}
] | 2015-06-24 | [
[
"Fariborz",
"Amir H.",
""
],
[
"Azizi",
"Azizollah",
""
],
[
"Asrar",
"Abdorreza",
""
]
] | Within an effective nonlinear chiral Lagrangian framework the substructure of $f_0(1370)$ is studied. The investigation is conducted in the context of a global picture of scalar mesons in which the importance of the underlying connections among scalar mesons below and above 1 GeV is recognized and implemented. These connections are due to the mixings among various quark-antiquarks, four-quarks and glue components and play a central role in understanding the properties of scalar mesons. Iterative Monte Carlo simulations are first performed on the 14-dimensional parameter space of the model and sets of points in this parameter space (the global sets) that give an overall agreement with all experimental data on mass spectrum, various decay widths and decay ratios of all isosinglet scalar states below 2 GeV are determined. Then within each global set, subsets that give closest agreement for the properties of $f_0(1370)$ are studied. Unlike the properties of other isosinglet states that show a range of variation within each global set, it is found that there is a clear signal for $f_0(1370)$ to be predominantly a quark-antiquark state with a substantial $s {\bar s}$ component, together with small remnants of four-quark and glue components. |
1802.04469 | Mohammad Athar SAJJAD | A. Fatima, M. Sajjad Athar and S. K. Singh | Polarization observables and T-noninvariance in the weak charged current
induced electron proton scattering | 16 pages, 11 figures and regular paper | null | 10.1140/epja/i2018-12534-2 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we have studied the total scattering cross section ($\sigma$),
differential scattering cross section ($d\sigma/dQ^2$) as well as the
longitudinal ($P_L(E_e,Q^2)$), perpendicular ($P_P(E_e,Q^2)$), and transverse
($P_T(E_e,Q^2)$) components of the polarization of the final hadron ($n$, $
\Lambda$ and $\Sigma^0$) produced in the electron proton scattering induced by
the weak charged current. We have not assumed T-invariance which allows the
transverse component of the hadron polarization perpendicular to the production
plane to be non-zero. The numerical results are presented for all the above
observables and their dependence on the axial vector form factor and the weak
electric form factor are discussed. The present study enables the determination
of the axial vector nucleon-hyperon transition form factors at high $ Q^2$ in
the strangeness sector which can provide test of the symmetries of the weak
hadronic currents like T-invariance and SU(3) symmetry while assuming the
hypothesis of conserved vector current and partial conservation of axial vector
current.
| [
{
"created": "Tue, 13 Feb 2018 06:00:29 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Nov 2018 08:05:01 GMT",
"version": "v2"
}
] | 2018-11-19 | [
[
"Fatima",
"A.",
""
],
[
"Athar",
"M. Sajjad",
""
],
[
"Singh",
"S. K.",
""
]
] | In this work, we have studied the total scattering cross section ($\sigma$), differential scattering cross section ($d\sigma/dQ^2$) as well as the longitudinal ($P_L(E_e,Q^2)$), perpendicular ($P_P(E_e,Q^2)$), and transverse ($P_T(E_e,Q^2)$) components of the polarization of the final hadron ($n$, $ \Lambda$ and $\Sigma^0$) produced in the electron proton scattering induced by the weak charged current. We have not assumed T-invariance which allows the transverse component of the hadron polarization perpendicular to the production plane to be non-zero. The numerical results are presented for all the above observables and their dependence on the axial vector form factor and the weak electric form factor are discussed. The present study enables the determination of the axial vector nucleon-hyperon transition form factors at high $ Q^2$ in the strangeness sector which can provide test of the symmetries of the weak hadronic currents like T-invariance and SU(3) symmetry while assuming the hypothesis of conserved vector current and partial conservation of axial vector current. |
2405.07894 | Debajit Bose | Debajit Bose, Rohan Pramanick, and Tirtha Sankar Ray | Neutrinos from captured dark matter in galactic stars | 12 pages, 4 figures | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Sub-GeV neutrinos produced in a stellar core may emerge from main sequence
stars, white dwarfs and brown dwarfs producing possible observable signals of
dark matter capture. A distribution of these stars near the Milky Way galactic
center will produce a neutrino flux that can be probed at Earth based neutrino
observatories like Super-Kamiokande. We demonstrate that this can provide a
handle to probe dark matter masses in the 100 MeV - 2 GeV mass scales that
compares favourably with present day direct detection bounds.
| [
{
"created": "Mon, 13 May 2024 16:29:35 GMT",
"version": "v1"
}
] | 2024-05-14 | [
[
"Bose",
"Debajit",
""
],
[
"Pramanick",
"Rohan",
""
],
[
"Ray",
"Tirtha Sankar",
""
]
] | Sub-GeV neutrinos produced in a stellar core may emerge from main sequence stars, white dwarfs and brown dwarfs producing possible observable signals of dark matter capture. A distribution of these stars near the Milky Way galactic center will produce a neutrino flux that can be probed at Earth based neutrino observatories like Super-Kamiokande. We demonstrate that this can provide a handle to probe dark matter masses in the 100 MeV - 2 GeV mass scales that compares favourably with present day direct detection bounds. |
hep-ph/0605115 | Igor M. Suslov | I. M. Suslov (P.L.Kapitza Institute for Physical Problems, Moscow,
Russia) | On 't Hooft's representation of the \beta-function | LaTex, 9 pages, 2 figures included | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is demonstrated, that 't Hooft's renormalization scheme (in which
\beta-function has exactly the two-loop form) is generally in conflict with the
natural physical requirements and specifies the type of the field theory in an
arbitrary manner. It violates analytic properties in the coupling constant
plane and provokes misleading conclusion on accumulation of singularities near
the origin. It artificially creates renormalon singularities, even if they are
absent in the physical scheme. The 't Hooft scheme can be used in the framework
of perturbation theory but no global conclusions should be drawn from it.
| [
{
"created": "Wed, 10 May 2006 14:14:02 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Feb 2008 18:58:50 GMT",
"version": "v2"
},
{
"created": "Fri, 6 Jun 2008 16:01:56 GMT",
"version": "v3"
}
] | 2008-06-06 | [
[
"Suslov",
"I. M.",
"",
"P.L.Kapitza Institute for Physical Problems, Moscow,\n Russia"
]
] | It is demonstrated, that 't Hooft's renormalization scheme (in which \beta-function has exactly the two-loop form) is generally in conflict with the natural physical requirements and specifies the type of the field theory in an arbitrary manner. It violates analytic properties in the coupling constant plane and provokes misleading conclusion on accumulation of singularities near the origin. It artificially creates renormalon singularities, even if they are absent in the physical scheme. The 't Hooft scheme can be used in the framework of perturbation theory but no global conclusions should be drawn from it. |
2011.02682 | Binoy Patra Krishna | Salman Ahamad Khan and Binoy Krishna Patra | Cumulative effects of collision integral, strong magnetic field, and
quasiparticle description on charge and heat transport in thermal QCD medium | 35 pages, 12 figures | Phys. Rev. D 104, 054024 (2021) | 10.1103/PhysRevD.104.054024 | null | hep-ph cond-mat.soft cond-mat.stat-mech cond-mat.str-el nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Our first aim is to explore the effect of the collision integral with the
insurance of instantaneous conservation of particle number on charge and heat
transport in a thermal QCD medium. The second aim is to see how the dimensional
reduction due to strong magnetic field (B) modulates the transport through the
entangled effects, {\em such as} collision-time and occupation probability etc.
in collision integral. The final aim is to check how the quasiparticle
description through dispersion relation of thermal QCD in strong B, alters the
aforesaid conclusions. We observe that modified collision term expedites both
transport, which is manifested by large magnitudes of electrical ($\sigma_{\rm
el}$) and thermal ($\kappa$) conductivities, in comparison to
relaxation-collision term. As a corollary, Lorenz number is dominated by the
later and Knudsen number is by the former. However, strong B not only flips the
dominance of collision term in heat transport, it also causes drastic
enhancement of both $\sigma_{\rm el}$ and $\kappa$ and reduction in specific
heat. As a result, the equilibration factor, Knudsen number becomes much larger
than one, which defies physical interpretation. Finally, quasiparticle
description in the absence of strong B impedes the transport of charge and
heat, resulting in the meagre decrease of conductivities, however, strong B
does noticeable observations: conductivities now gets reduced to physically
plausible values, T-dependence of $\sigma_{\rm el}$ gets reversed, {\em i.e.}
it now decreases with T, effect of collision integral gets smeared in $\kappa$
etc. Knudsen number thus becomes much smaller than one, implying that the
system be remained in equilibrium. These findings attribute to the fact that
the collective modes in the dispersion relation of thermal QCD in strong B sets
in much larger scale, manifested by large in-medium masses.
| [
{
"created": "Thu, 5 Nov 2020 06:54:23 GMT",
"version": "v1"
},
{
"created": "Sun, 22 Aug 2021 13:52:49 GMT",
"version": "v2"
}
] | 2021-09-29 | [
[
"Khan",
"Salman Ahamad",
""
],
[
"Patra",
"Binoy Krishna",
""
]
] | Our first aim is to explore the effect of the collision integral with the insurance of instantaneous conservation of particle number on charge and heat transport in a thermal QCD medium. The second aim is to see how the dimensional reduction due to strong magnetic field (B) modulates the transport through the entangled effects, {\em such as} collision-time and occupation probability etc. in collision integral. The final aim is to check how the quasiparticle description through dispersion relation of thermal QCD in strong B, alters the aforesaid conclusions. We observe that modified collision term expedites both transport, which is manifested by large magnitudes of electrical ($\sigma_{\rm el}$) and thermal ($\kappa$) conductivities, in comparison to relaxation-collision term. As a corollary, Lorenz number is dominated by the later and Knudsen number is by the former. However, strong B not only flips the dominance of collision term in heat transport, it also causes drastic enhancement of both $\sigma_{\rm el}$ and $\kappa$ and reduction in specific heat. As a result, the equilibration factor, Knudsen number becomes much larger than one, which defies physical interpretation. Finally, quasiparticle description in the absence of strong B impedes the transport of charge and heat, resulting in the meagre decrease of conductivities, however, strong B does noticeable observations: conductivities now gets reduced to physically plausible values, T-dependence of $\sigma_{\rm el}$ gets reversed, {\em i.e.} it now decreases with T, effect of collision integral gets smeared in $\kappa$ etc. Knudsen number thus becomes much smaller than one, implying that the system be remained in equilibrium. These findings attribute to the fact that the collective modes in the dispersion relation of thermal QCD in strong B sets in much larger scale, manifested by large in-medium masses. |
1108.2318 | Radhey Shyam | R. Shyam, O. Scholten and A.W. Thomas | Production of a cascade hyperon in the K^- - proton interaction | 11 pages, 5 figures | Physical Review C 84, 042201(R) (2011) | 10.1103/PhysRevC.84.042201 | ADP-11-21/T743 | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the production of a cascade hyperon (Xi) through the K^- + p
--> K^+ (K^0) + Xi^- (Xi^0) reactions, within an effective Lagrangian model
where these reactions proceed via excitations of Lambda and Sigma resonance
intermediate states in s- and u-channels. The coupling constants at the various
vertices are taken from previous studies and SU(3) symmetry considerations. The
calculated total cross sections of these reactions, which are in good agreement
with the available data, are dominated by the contributions from the
Lambda(1520) intermediate resonant state. However, the K^+ meson angular
distributions show selectivity to other resonant states in different angular
regions and interference among these states leads to their strong backward
peaking.
| [
{
"created": "Thu, 11 Aug 2011 01:35:14 GMT",
"version": "v1"
}
] | 2015-03-19 | [
[
"Shyam",
"R.",
""
],
[
"Scholten",
"O.",
""
],
[
"Thomas",
"A. W.",
""
]
] | We investigate the production of a cascade hyperon (Xi) through the K^- + p --> K^+ (K^0) + Xi^- (Xi^0) reactions, within an effective Lagrangian model where these reactions proceed via excitations of Lambda and Sigma resonance intermediate states in s- and u-channels. The coupling constants at the various vertices are taken from previous studies and SU(3) symmetry considerations. The calculated total cross sections of these reactions, which are in good agreement with the available data, are dominated by the contributions from the Lambda(1520) intermediate resonant state. However, the K^+ meson angular distributions show selectivity to other resonant states in different angular regions and interference among these states leads to their strong backward peaking. |
hep-ph/0407207 | Lech Szymanowski dr | D.Yu. Ivanov, L. Szymanowski, G. Krasnikov | Vector meson electroproduction at next-to-leading order | latex, 6 pages, with corrected Eq. (12) and added remark on
dimensional regularisation | JETP Lett. 80 (2004) 226-230; Pisma Zh.Eksp.Teor.Fiz. 80 (2004)
255-259 | 10.1134/1.1813676 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The process of a light neutral vector meson electroproduction is studied in
the framework of QCD factorization in which the amplitude factorizes in a
convolution of the nonperturbative meson distribution amplitude and the
generalized parton densities with the perturbatively calculable hard-scattering
amplitudes. We derive a complete set of hard-scattering amplitudes at
next-to-leading order for the production of vector mesons, $V=\rho^0, \omega,
\phi$.
| [
{
"created": "Mon, 19 Jul 2004 10:04:58 GMT",
"version": "v1"
},
{
"created": "Tue, 26 May 2015 15:03:21 GMT",
"version": "v2"
}
] | 2015-05-27 | [
[
"Ivanov",
"D. Yu.",
""
],
[
"Szymanowski",
"L.",
""
],
[
"Krasnikov",
"G.",
""
]
] | The process of a light neutral vector meson electroproduction is studied in the framework of QCD factorization in which the amplitude factorizes in a convolution of the nonperturbative meson distribution amplitude and the generalized parton densities with the perturbatively calculable hard-scattering amplitudes. We derive a complete set of hard-scattering amplitudes at next-to-leading order for the production of vector mesons, $V=\rho^0, \omega, \phi$. |
hep-ph/0110341 | Pran Nath | Utpal Chattopadhyay and Pran Nath | $b-\tau$ Unification, $g_{\mu}-2$, the $b\to s+\gamma$ Constraint and
Nonuniversalities | 25 pages,Latex including 10 figs. TIFR/TH/01-04, NUB-TH/3222 | Phys.Rev.D65:075009,2002 | 10.1103/PhysRevD.65.075009 | null | hep-ph | null | An analysis is given of the $b-\tau$ Yukawa coupling unification in view of
the recent result from Brookhaven on $g_{\mu}-2$ and under the constraint of
$b\to s+\gamma$. We explore $b-\tau$ unification under the above constraints
for nonuniversal boundary conditions for the soft SUSY breaking parameters. We
find new regions of the parameter space where significant negative
supersymmetric contribution to the b quark mass can arise and $b-\tau$
unification within SU(5) framework can occur with nonuniversal gaugino masses.
Specifically we find that for the case where the gaugino mass matrix transforms
like a 24 plet one finds a negative contribution to the b quark mass
irrespective of the sign of the Higgs mixing parameter $\mu$ when the
supersymmetric contribution to $g_{\mu}-2$ is positive. We exhibit regions of
the parameter space where $b-\tau$ unification occurs for $\mu>0$ satisfying
the constraints of $b\to s+\gamma$ and $g_\mu-2$. The $\mu<0$ case is also
explored. The dependence of the accuracy of $b-\tau$ unification defined by
$|\lambda_b-\lambda_{\tau}|/\lambda_{\tau}$ on the parameter space is also
investigated and it is shown that unification with an accuracy of a few percent
can be achieved in significant regions of the parameter space. The allowed
parameter space is consistent with the naturalness constraints and the
corresponding sparticle spectrum is accessible at the Large Hadron Collider.
| [
{
"created": "Thu, 25 Oct 2001 20:40:22 GMT",
"version": "v1"
}
] | 2011-07-18 | [
[
"Chattopadhyay",
"Utpal",
""
],
[
"Nath",
"Pran",
""
]
] | An analysis is given of the $b-\tau$ Yukawa coupling unification in view of the recent result from Brookhaven on $g_{\mu}-2$ and under the constraint of $b\to s+\gamma$. We explore $b-\tau$ unification under the above constraints for nonuniversal boundary conditions for the soft SUSY breaking parameters. We find new regions of the parameter space where significant negative supersymmetric contribution to the b quark mass can arise and $b-\tau$ unification within SU(5) framework can occur with nonuniversal gaugino masses. Specifically we find that for the case where the gaugino mass matrix transforms like a 24 plet one finds a negative contribution to the b quark mass irrespective of the sign of the Higgs mixing parameter $\mu$ when the supersymmetric contribution to $g_{\mu}-2$ is positive. We exhibit regions of the parameter space where $b-\tau$ unification occurs for $\mu>0$ satisfying the constraints of $b\to s+\gamma$ and $g_\mu-2$. The $\mu<0$ case is also explored. The dependence of the accuracy of $b-\tau$ unification defined by $|\lambda_b-\lambda_{\tau}|/\lambda_{\tau}$ on the parameter space is also investigated and it is shown that unification with an accuracy of a few percent can be achieved in significant regions of the parameter space. The allowed parameter space is consistent with the naturalness constraints and the corresponding sparticle spectrum is accessible at the Large Hadron Collider. |
1804.11333 | Ying-nan Mao | Shi-Ping He, Ying-nan Mao, Chen Zhang, Shou-hua Zhu | $ZH\eta$-vertex: EFT Analysis and the Behavior in the SLH Model | Talk at the 53rd Rencontres de Moriond (EW 2018); 6 pages;
presentation (especially the abstract part) refined | null | null | NCTS-PH-1806 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We re-analyze the $ZH\eta$-vertex with the form
$Z_{\mu}(\eta\partial^{\mu}H-H\partial^{\mu}\eta)$, where $H$ is the 125 GeV
Higgs boson and $\eta$ is an exotic pseudo-axion, based on the effective field
theory (EFT) analysis and choose the simplest little Higgs (SLH) model as an
example. For a pure gauge singlet pseudoscalar $\eta$, after carefully removing
all off-diagonal two-point transitions, we show that its coefficient
$c_{ZH\eta}$ cannot appear before $\mathcal{O}(\xi^3)$ level, where $\xi$ is
the ratio between the electro-weak scale $v$ and a high scale $f$. The same
behavior arises in the simplest little Higgs (SLH) model, which is quite
different from the result that has already existed for a long time.
| [
{
"created": "Mon, 30 Apr 2018 17:27:07 GMT",
"version": "v1"
},
{
"created": "Mon, 7 May 2018 06:09:02 GMT",
"version": "v2"
}
] | 2018-05-08 | [
[
"He",
"Shi-Ping",
""
],
[
"Mao",
"Ying-nan",
""
],
[
"Zhang",
"Chen",
""
],
[
"Zhu",
"Shou-hua",
""
]
] | We re-analyze the $ZH\eta$-vertex with the form $Z_{\mu}(\eta\partial^{\mu}H-H\partial^{\mu}\eta)$, where $H$ is the 125 GeV Higgs boson and $\eta$ is an exotic pseudo-axion, based on the effective field theory (EFT) analysis and choose the simplest little Higgs (SLH) model as an example. For a pure gauge singlet pseudoscalar $\eta$, after carefully removing all off-diagonal two-point transitions, we show that its coefficient $c_{ZH\eta}$ cannot appear before $\mathcal{O}(\xi^3)$ level, where $\xi$ is the ratio between the electro-weak scale $v$ and a high scale $f$. The same behavior arises in the simplest little Higgs (SLH) model, which is quite different from the result that has already existed for a long time. |
0710.4067 | Eef van Beveren | E. van Beveren, T.A. Rijken, K. Metzger, C. Dullemond, G. Rupp and
J.E. Ribeiro | A low-lying scalar meson nonet in a unitarized meson model | A slightly revised version of Zeitschrift fuer Physik C30, 615 (1986) | Z.Phys.C30:615-620,1986 | 10.1007/BF01571811 | null | hep-ph | null | A unitarized nonrelativistic meson model which is successful for the
description of the heavy and light vector and pseudoscalar mesons yields, in
its extension to the scalar mesons but for the same model parameters, a
complete nonet below 1 GeV. In the unitarization scheme, real and virtual
meson-meson decay channels are coupled to the quark-antiquark confinement
channels. The flavor-dependent harmonic-oscillator confining potential itself
has bound states epsilon(1.3 GeV), S(1.5 GeV), delta(1.3 GeV), kappa(1.4 GeV),
similar to the results of other bound-state qqbar models. However, the full
coupled-channel equations show poles at epsilon(0.5 GeV), S(0.99 GeV),
delta(0.97 GeV), kappa(0.73 GeV). Not only can these pole positions be
calculated in our model, but also cross sections and phase shifts in the
meson-scattering channels, which are in reasonable agreement with the available
data for pion-pion, eta-pion and Kaon-pion in S-wave scattering.
| [
{
"created": "Mon, 22 Oct 2007 14:29:19 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"van Beveren",
"E.",
""
],
[
"Rijken",
"T. A.",
""
],
[
"Metzger",
"K.",
""
],
[
"Dullemond",
"C.",
""
],
[
"Rupp",
"G.",
""
],
[
"Ribeiro",
"J. E.",
""
]
] | A unitarized nonrelativistic meson model which is successful for the description of the heavy and light vector and pseudoscalar mesons yields, in its extension to the scalar mesons but for the same model parameters, a complete nonet below 1 GeV. In the unitarization scheme, real and virtual meson-meson decay channels are coupled to the quark-antiquark confinement channels. The flavor-dependent harmonic-oscillator confining potential itself has bound states epsilon(1.3 GeV), S(1.5 GeV), delta(1.3 GeV), kappa(1.4 GeV), similar to the results of other bound-state qqbar models. However, the full coupled-channel equations show poles at epsilon(0.5 GeV), S(0.99 GeV), delta(0.97 GeV), kappa(0.73 GeV). Not only can these pole positions be calculated in our model, but also cross sections and phase shifts in the meson-scattering channels, which are in reasonable agreement with the available data for pion-pion, eta-pion and Kaon-pion in S-wave scattering. |
1012.4808 | Jamison Galloway | Jared A. Evans, Jamison Galloway, Markus A. Luty, Ruggero Altair
Tacchi | Flavor in Minimal Conformal Technicolor | 37 pages; references added | null | 10.1007/JHEP04(2011)003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a complete, realistic, and natural UV completion of minimal
conformal technicolor that explains the origin of quark and lepton masses and
mixing angles. As in "bosonic technicolor", we embed conformal technicolor in a
supersymmetric theory, with supersymmetry broken at a high scale. The exchange
of heavy scalar doublets generates higher-dimension interactions between
technifermions and quarks and leptons that give rise to quark and lepton masses
at the TeV scale. Obtaining a sufficiently large top quark mass requires strong
dynamics at the supersymmetry breaking scale in both the top and technicolor
sectors. This is natural if the theory above the supersymmetry breaking also
has strong conformal dynamics. We present two models in which the strong top
dynamics is realized in different ways. In both models, constraints from
flavor-changing effects can be easily satisfied. The effective theory below the
supersymmetry breaking scale is minimal conformal technicolor with an
additional light technicolor gaugino. We argue that this light gaugino is a
general consequence of conformal technicolor embedded into a supersymmetric
theory. If the gaugino has mass below the TeV scale it will give rise to an
additional pseudo Nambu-Goldstone boson that is observable at the LHC.
| [
{
"created": "Tue, 21 Dec 2010 21:03:06 GMT",
"version": "v1"
},
{
"created": "Thu, 3 Mar 2011 22:55:02 GMT",
"version": "v2"
}
] | 2015-05-20 | [
[
"Evans",
"Jared A.",
""
],
[
"Galloway",
"Jamison",
""
],
[
"Luty",
"Markus A.",
""
],
[
"Tacchi",
"Ruggero Altair",
""
]
] | We construct a complete, realistic, and natural UV completion of minimal conformal technicolor that explains the origin of quark and lepton masses and mixing angles. As in "bosonic technicolor", we embed conformal technicolor in a supersymmetric theory, with supersymmetry broken at a high scale. The exchange of heavy scalar doublets generates higher-dimension interactions between technifermions and quarks and leptons that give rise to quark and lepton masses at the TeV scale. Obtaining a sufficiently large top quark mass requires strong dynamics at the supersymmetry breaking scale in both the top and technicolor sectors. This is natural if the theory above the supersymmetry breaking also has strong conformal dynamics. We present two models in which the strong top dynamics is realized in different ways. In both models, constraints from flavor-changing effects can be easily satisfied. The effective theory below the supersymmetry breaking scale is minimal conformal technicolor with an additional light technicolor gaugino. We argue that this light gaugino is a general consequence of conformal technicolor embedded into a supersymmetric theory. If the gaugino has mass below the TeV scale it will give rise to an additional pseudo Nambu-Goldstone boson that is observable at the LHC. |
hep-ph/0311135 | Junfeng Sun | Dongsheng Du | Global analysis of B-->PP, PV charmless decays with QCD factorization | Revtex4, 12 pages, 4 figures, Talk given at the International
Conference on Flavour Physics, Seoul, Korea, 6--11 October, 2003 | J.Korean Phys.Soc. 45 (2004) S285-S291 | null | null | hep-ph | null | The global analysis of B-->PP, PV charmless decays with QCD factorization
(QCDF) is presented. The predictions of QCDF are in good agreement with
experiments. The best fitted CKM angel gamma is around 79 degree. The predicted
branching ratios of B --> pi^0 pi^0, omega K^+, omega pi^+, pi^+ K^{{\ast}0}
etc. are also in good agreement with new data of BaBar and Belle
| [
{
"created": "Tue, 11 Nov 2003 03:38:10 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Du",
"Dongsheng",
""
]
] | The global analysis of B-->PP, PV charmless decays with QCD factorization (QCDF) is presented. The predictions of QCDF are in good agreement with experiments. The best fitted CKM angel gamma is around 79 degree. The predicted branching ratios of B --> pi^0 pi^0, omega K^+, omega pi^+, pi^+ K^{{\ast}0} etc. are also in good agreement with new data of BaBar and Belle |
hep-ph/9412271 | null | S.I. Eidelman, E.A. Kuraev, Z.K. Silagadze | $\rho\to 4\pi$ DECAY | 6 pages, LaTeX, without figure. Submitted to Phys. Lett. B | Phys.Lett. B346 (1995) 186-189 | 10.1016/0370-2693(94)01697-B | BudkerINP 94-87 (Novosibirsk) | hep-ph | null | The decay modes $\rho^0 \to 2\pi^+ 2\pi^-$ and $\rho^0 \to 2\pi^0 \pi^+
\pi^-$ are considered in the framework of the low energy effective chiral
Lagrangian. The obtained values of the decay widths $\Gamma(\rho^0\to 2 \pi^+ 2
\pi^-)=$ $(16 \pm 1){\rm keV}$ and $\Gamma(\rho^0\to 2 \pi^0 \pi^+ \pi^-)= (6.0
\pm 0.2)$keV do not contradict the existing upper limits and seem to be big
enough for the corresponding processes to be observed in future high luminosity
experiments.
| [
{
"created": "Sat, 10 Dec 1994 14:02:27 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Eidelman",
"S. I.",
""
],
[
"Kuraev",
"E. A.",
""
],
[
"Silagadze",
"Z. K.",
""
]
] | The decay modes $\rho^0 \to 2\pi^+ 2\pi^-$ and $\rho^0 \to 2\pi^0 \pi^+ \pi^-$ are considered in the framework of the low energy effective chiral Lagrangian. The obtained values of the decay widths $\Gamma(\rho^0\to 2 \pi^+ 2 \pi^-)=$ $(16 \pm 1){\rm keV}$ and $\Gamma(\rho^0\to 2 \pi^0 \pi^+ \pi^-)= (6.0 \pm 0.2)$keV do not contradict the existing upper limits and seem to be big enough for the corresponding processes to be observed in future high luminosity experiments. |
hep-ph/0606095 | Robert Harlander | Robert Harlander | Standard and SUSY Higgs production at the LHC | 9 pages, 3 figures (4 ps-files). Contribution to the proceedings of
WHEPP-9 (Jan 1-14, 2006, Bhubaneswar, India) | Pramana67:875-884,2006 | 10.1007/s12043-006-0099-5 | null | hep-ph | null | Recent theoretical developments concerning Higgs production at the Large
Hadron Collider are reviewed, both in the Standard Model and in the MSSM.
Emphasis is put on the inclusive and exclusive cross sections for gluon fusion,
as well as on the associated production with bottom quarks.
| [
{
"created": "Thu, 8 Jun 2006 13:20:29 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Harlander",
"Robert",
""
]
] | Recent theoretical developments concerning Higgs production at the Large Hadron Collider are reviewed, both in the Standard Model and in the MSSM. Emphasis is put on the inclusive and exclusive cross sections for gluon fusion, as well as on the associated production with bottom quarks. |
2307.15304 | Daiki Suenaga | Hiroto Takada, Daiki Suenaga, Masayasu Harada, Atsushi Hosaka and
Makoto Oka | Axial anomaly effect on three-quark and five-quark singly heavy baryons | 15 pages, 10 figures | Phys. Rev. D108, 054033 (2023) | 10.1103/PhysRevD.108.054033 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | Effects of the $U(1)_A$ axial anomaly on the mass spectrum of singly heavy
baryons (SHBs) is studied in terms of the chiral effective theory based on the
chiral linear representation for light flavors. We consider SHBs made of both
three quarks ($Qqq$) and five quarks ($Qqqq\bar{q}$). For the three-quark SHBs
we prove that the inverse mass hierarchy for the negative-parity $\Lambda_c$
and $\Xi_c$ is realized only when the $U(1)_A$ anomaly is present. For the
five-quark SHBs, in contrast, it is found that the $U(1)_A$ anomaly does not
change the mass spectrum at the leading order, and accordingly their decay
properties induced by emitting a pseudoscalar meson are not affected by the
anomaly. Moreover, taking into account small mixings between the three-quark
and five-quark SHBs, we find that the observed $\Xi_c$ excited state, either
$\Xi_c(2923)$ or $\Xi_c(2930)$, can be consistently regarded as a
negative-parity SHB that is dominated by the five-quark component. We also
predict a new negative-parity five-quark dominant $\Lambda_c$, whose mass is
around $2700$ MeV and the decay width is of order a few MeV, which provides
useful information for future experiments to check our description.
| [
{
"created": "Fri, 28 Jul 2023 04:46:29 GMT",
"version": "v1"
}
] | 2023-10-02 | [
[
"Takada",
"Hiroto",
""
],
[
"Suenaga",
"Daiki",
""
],
[
"Harada",
"Masayasu",
""
],
[
"Hosaka",
"Atsushi",
""
],
[
"Oka",
"Makoto",
""
]
] | Effects of the $U(1)_A$ axial anomaly on the mass spectrum of singly heavy baryons (SHBs) is studied in terms of the chiral effective theory based on the chiral linear representation for light flavors. We consider SHBs made of both three quarks ($Qqq$) and five quarks ($Qqqq\bar{q}$). For the three-quark SHBs we prove that the inverse mass hierarchy for the negative-parity $\Lambda_c$ and $\Xi_c$ is realized only when the $U(1)_A$ anomaly is present. For the five-quark SHBs, in contrast, it is found that the $U(1)_A$ anomaly does not change the mass spectrum at the leading order, and accordingly their decay properties induced by emitting a pseudoscalar meson are not affected by the anomaly. Moreover, taking into account small mixings between the three-quark and five-quark SHBs, we find that the observed $\Xi_c$ excited state, either $\Xi_c(2923)$ or $\Xi_c(2930)$, can be consistently regarded as a negative-parity SHB that is dominated by the five-quark component. We also predict a new negative-parity five-quark dominant $\Lambda_c$, whose mass is around $2700$ MeV and the decay width is of order a few MeV, which provides useful information for future experiments to check our description. |
0911.2669 | Miccola Bondarenco | M.V. Bondarenco | Constituent Quark Rest Energy and Wave Function Across the Light Cone | 4 pages, 2 figures; Talk given at the XIII Workshop on High-Energy
Spin Physics (DSPIN-09), Dubna, Sept. 1-5, 2009, to appear in the proceedings | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that for a constituent quark in the intra-nucleon self-consistent
field the spin-orbit interaction lowers the quark rest energy to values
$\sim100$ MeV, which agrees with the DIS momentum sum rule. The possibility of
violation of the spectral condition for the light-cone momentum component of a
bound quark is discussed.
| [
{
"created": "Fri, 13 Nov 2009 18:11:02 GMT",
"version": "v1"
}
] | 2009-11-16 | [
[
"Bondarenco",
"M. V.",
""
]
] | It is shown that for a constituent quark in the intra-nucleon self-consistent field the spin-orbit interaction lowers the quark rest energy to values $\sim100$ MeV, which agrees with the DIS momentum sum rule. The possibility of violation of the spectral condition for the light-cone momentum component of a bound quark is discussed. |
2311.05391 | Satoshi Nakamura | S.X. Nakamura (Shandong Univ.), Q. Huang (Nanjing Normal Univ.), J.-J.
Wu (UCAS), H.P. Peng (USTC), Y. Zhang (USTC), Y.C. Zhu (USTC) | Three-body unitary coupled-channel approach to radiative $J/\psi$ decays
and $\eta(1405/1475)$ | 23 pages, 19 figures; (v2) minor changes, published version | Phys. Rev. D 109, 014021 (2024) | 10.1103/PhysRevD.109.014021 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent BESIII data on radiative $J/\psi$ decays from $\sim 10^{10}$ $J/\psi$
samples should significantly advance our understanding of the controversial
nature of $\eta(1405/1475)$. This motivates us to develop a three-body unitary
coupled-channel model for radiative $J/\psi$ decays to three-meson final states
of any partial wave ($J^{PC}$). Basic building blocks of the model are bare
resonance states such as $\eta(1405/1475)$ and $f_1(1420)$, and $\pi K$,
$K\bar{K}$, and $\pi\eta$ two-body interactions that generate resonances such
as $K^*(892)$, $K^*_0(700)$, and $a_0(980)$. This model reasonably fits
$K_SK_S\pi^0$ Dalitz plot pseudo data generated from the BESIII's
$J^{PC}=0^{-+}$ amplitude for $J/\psi\to\gamma K_SK_S\pi^0$. The experimental
branching ratios of $\eta(1405/1475)\to\eta\pi\pi$ and
$\eta(1405/1475)\to\gamma\rho$ relative to that of $\eta(1405/1475)\to
K\bar{K}\pi$ are simultaneously fitted. Our $0^{-+}$ amplitude is analytically
continued to find three poles, two of which correspond to $\eta(1405)$ on
different Riemann sheets of the $K^*\bar{K}$ channel, and the third one for
$\eta(1475)$. This is the first pole determination of $\eta(1405/1475)$ and,
furthermore, the first-ever pole determination from analyzing experimental
Dalitz plot distributions with a manifestly three-body unitary coupled-channel
framework. Process-dependent $\eta\pi\pi$, $\gamma\pi^+\pi^-$, and $\pi\pi\pi$
lineshapes of $J/\psi\to\gamma(0^{-+})\to \gamma(\eta\pi\pi)$,
$\gamma(\gamma\rho)$, and $\gamma(\pi\pi\pi)$ are predicted, and are in
reasonable agreement with data. A triangle singularity is shown to play a
crucial role to cause the large isospin violation of
$J/\psi\to\gamma(\pi\pi\pi)$.
| [
{
"created": "Thu, 9 Nov 2023 14:20:19 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Jan 2024 18:48:11 GMT",
"version": "v2"
}
] | 2024-01-23 | [
[
"Nakamura",
"S. X.",
"",
"Shandong Univ."
],
[
"Huang",
"Q.",
"",
"Nanjing Normal Univ."
],
[
"Wu",
"J. -J.",
"",
"UCAS"
],
[
"Peng",
"H. P.",
"",
"USTC"
],
[
"Zhang",
"Y.",
"",
"USTC"
],
[
"Zhu",
"Y. C.",
"",
"USTC"
]
] | Recent BESIII data on radiative $J/\psi$ decays from $\sim 10^{10}$ $J/\psi$ samples should significantly advance our understanding of the controversial nature of $\eta(1405/1475)$. This motivates us to develop a three-body unitary coupled-channel model for radiative $J/\psi$ decays to three-meson final states of any partial wave ($J^{PC}$). Basic building blocks of the model are bare resonance states such as $\eta(1405/1475)$ and $f_1(1420)$, and $\pi K$, $K\bar{K}$, and $\pi\eta$ two-body interactions that generate resonances such as $K^*(892)$, $K^*_0(700)$, and $a_0(980)$. This model reasonably fits $K_SK_S\pi^0$ Dalitz plot pseudo data generated from the BESIII's $J^{PC}=0^{-+}$ amplitude for $J/\psi\to\gamma K_SK_S\pi^0$. The experimental branching ratios of $\eta(1405/1475)\to\eta\pi\pi$ and $\eta(1405/1475)\to\gamma\rho$ relative to that of $\eta(1405/1475)\to K\bar{K}\pi$ are simultaneously fitted. Our $0^{-+}$ amplitude is analytically continued to find three poles, two of which correspond to $\eta(1405)$ on different Riemann sheets of the $K^*\bar{K}$ channel, and the third one for $\eta(1475)$. This is the first pole determination of $\eta(1405/1475)$ and, furthermore, the first-ever pole determination from analyzing experimental Dalitz plot distributions with a manifestly three-body unitary coupled-channel framework. Process-dependent $\eta\pi\pi$, $\gamma\pi^+\pi^-$, and $\pi\pi\pi$ lineshapes of $J/\psi\to\gamma(0^{-+})\to \gamma(\eta\pi\pi)$, $\gamma(\gamma\rho)$, and $\gamma(\pi\pi\pi)$ are predicted, and are in reasonable agreement with data. A triangle singularity is shown to play a crucial role to cause the large isospin violation of $J/\psi\to\gamma(\pi\pi\pi)$. |
1408.6076 | Michael Klasen | M. Klasen | Implications of the Higgs discovery on minimal dark matter | 3 pages, 7 figures, proceedings of ICHEP 2014 | null | null | MS-TP-14-28 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The existence of dark matter provides compelling evidence for physics beyond
the Standard Model. Minimal extensions of the Standard Model with additional
scalars or fermions allow to explain the observed dark matter relic density in
an economic way. We analyse several of these possibilities like the inert Higgs
and radiative seesaw models in the light of the recent Higgs discovery and
study prospects for the direct and indirect detection of dark matter in these
models.
| [
{
"created": "Tue, 26 Aug 2014 11:24:28 GMT",
"version": "v1"
}
] | 2014-08-27 | [
[
"Klasen",
"M.",
""
]
] | The existence of dark matter provides compelling evidence for physics beyond the Standard Model. Minimal extensions of the Standard Model with additional scalars or fermions allow to explain the observed dark matter relic density in an economic way. We analyse several of these possibilities like the inert Higgs and radiative seesaw models in the light of the recent Higgs discovery and study prospects for the direct and indirect detection of dark matter in these models. |
hep-ph/0503013 | Raymond F. Sawyer | R. F. Sawyer | Speed-up of neutrino transformations in a supernova environment | 8 pages, 4 figures | Phys.Rev. D72 (2005) 045003 | 10.1103/PhysRevD.72.045003 | null | hep-ph astro-ph | null | When the neutral current neutrino-neutrino interaction is treated completely,
rather than as an interaction among angle-averaged distributions, or as a set
of flavor-diagonal effective potentials, the result can be flavor mixing at a
speed orders of magnitude faster than that one would anticipate from the
measured neutrino oscillation parameters. It is possible that the energy
spectra of the three active species of neutrinos emerging from a supernova are
nearly identical.
| [
{
"created": "Tue, 1 Mar 2005 17:35:27 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Sawyer",
"R. F.",
""
]
] | When the neutral current neutrino-neutrino interaction is treated completely, rather than as an interaction among angle-averaged distributions, or as a set of flavor-diagonal effective potentials, the result can be flavor mixing at a speed orders of magnitude faster than that one would anticipate from the measured neutrino oscillation parameters. It is possible that the energy spectra of the three active species of neutrinos emerging from a supernova are nearly identical. |
0905.1022 | Yuki Adachi | Yuki Adachi, C. S. Lim (Kobe-U) and Nobuhito Maru (Chuo-U) | Neutron Electric Dipole Moment in the Gauge-Higgs Unification | 18 pages | Phys.Rev.D80:055025,2009 | 10.1103/PhysRevD.80.055025 | KOBE-TH-09-02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the neutron electric dipole moment (EDM) in a five dimensional SU(3)
gauge-Higgs unification compactified on M^4 \times S^1/Z_2 space-time including
a massive fermion. We point out that to realize the CP violation is a
non-trivial task in the gauge-Higgs unification scenario and argue how the CP
symmetry is broken spontaneously by the VEV of the Higgs, the extra space
component of the gauge field. We emphasize the importance of the interplay
between the VEV of the Higgs and the Z_2-odd bulk mass term to get physically
the CP violation. We then calculate the one-loop contributions to the neutron
EDM as the typical example of the CP violating observable and find that the EDM
appears already at the one-loop level, without invoking to the three generation
scheme. We then derive a lower bound for the compactification scale, which is
around 2.6 TeV, by comparing the contribution due to the nonzero Kaluza-Klein
modes with the experimental data.
| [
{
"created": "Thu, 7 May 2009 13:40:53 GMT",
"version": "v1"
},
{
"created": "Mon, 25 May 2009 11:34:00 GMT",
"version": "v2"
}
] | 2009-11-06 | [
[
"Adachi",
"Yuki",
"",
"Kobe-U"
],
[
"Lim",
"C. S.",
"",
"Kobe-U"
],
[
"Maru",
"Nobuhito",
"",
"Chuo-U"
]
] | We study the neutron electric dipole moment (EDM) in a five dimensional SU(3) gauge-Higgs unification compactified on M^4 \times S^1/Z_2 space-time including a massive fermion. We point out that to realize the CP violation is a non-trivial task in the gauge-Higgs unification scenario and argue how the CP symmetry is broken spontaneously by the VEV of the Higgs, the extra space component of the gauge field. We emphasize the importance of the interplay between the VEV of the Higgs and the Z_2-odd bulk mass term to get physically the CP violation. We then calculate the one-loop contributions to the neutron EDM as the typical example of the CP violating observable and find that the EDM appears already at the one-loop level, without invoking to the three generation scheme. We then derive a lower bound for the compactification scale, which is around 2.6 TeV, by comparing the contribution due to the nonzero Kaluza-Klein modes with the experimental data. |
2007.13931 | Bartosz Fornal | Bartosz Fornal, Benjamin Grinstein | Neutron's Dark Secret | 19 pages, 4 figures; Invited review for Modern Physics Letters A | Mod. Phys. Lett. A 35, 2030019 (2020) | 10.1142/S0217732320300190 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The existing discrepancy between neutron lifetime measurements in bottle and
beam experiments has been interpreted as a sign of the neutron decaying to dark
particles. We summarize the current status of this proposal, including a
discussion of particle physics models involving such a portal between the
Standard Model and a baryonic dark sector. We also review further theoretical
developments around this idea and elaborate on the prospects for verifying the
neutron dark decay hypothesis in current and upcoming experiments.
| [
{
"created": "Tue, 28 Jul 2020 01:20:00 GMT",
"version": "v1"
}
] | 2020-10-13 | [
[
"Fornal",
"Bartosz",
""
],
[
"Grinstein",
"Benjamin",
""
]
] | The existing discrepancy between neutron lifetime measurements in bottle and beam experiments has been interpreted as a sign of the neutron decaying to dark particles. We summarize the current status of this proposal, including a discussion of particle physics models involving such a portal between the Standard Model and a baryonic dark sector. We also review further theoretical developments around this idea and elaborate on the prospects for verifying the neutron dark decay hypothesis in current and upcoming experiments. |
1403.2413 | Liang Zheng | L. Zheng, E.C. Aschenauer, J.H. Lee, Bo-Wen Xiao | Probing Gluon Saturation through Dihadron Correlations at an
Electron-Ion Collider | 13 pages, 13 eps figures | Phys. Rev. D 89, 074037 (2014) | 10.1103/PhysRevD.89.074037 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Two-particle azimuthal angle correlations have been proposed to be one of the
most direct and sensitive probes to access the underlying gluon dynamics
involved in hard scatterings. In anticipation of an Electron-Ion Collider
(EIC), detailed studies of dihadron correlation measurements in electron-proton
and electron-ion collisions at an EIC have been performed. The impact of such
measurements on the understanding of the different gluon distribution
functions, as a clean signature for gluon saturation and to constrain
saturation models further, has been explored. It is shown that dihadron
correlation measurements will be one of the key methods to probe gluon
saturation phenomena at a future EIC.
| [
{
"created": "Mon, 10 Mar 2014 21:13:00 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Mar 2014 13:34:33 GMT",
"version": "v2"
},
{
"created": "Mon, 7 Apr 2014 13:37:38 GMT",
"version": "v3"
}
] | 2014-04-30 | [
[
"Zheng",
"L.",
""
],
[
"Aschenauer",
"E. C.",
""
],
[
"Lee",
"J. H.",
""
],
[
"Xiao",
"Bo-Wen",
""
]
] | Two-particle azimuthal angle correlations have been proposed to be one of the most direct and sensitive probes to access the underlying gluon dynamics involved in hard scatterings. In anticipation of an Electron-Ion Collider (EIC), detailed studies of dihadron correlation measurements in electron-proton and electron-ion collisions at an EIC have been performed. The impact of such measurements on the understanding of the different gluon distribution functions, as a clean signature for gluon saturation and to constrain saturation models further, has been explored. It is shown that dihadron correlation measurements will be one of the key methods to probe gluon saturation phenomena at a future EIC. |
hep-ph/0009100 | Boos Edward E. | E.E.Boos | Top Quarks at Photon Colliders | 12 pages, 10 figures, talk given at the International Workshop on
High Energy Photon Colliders, 14-17 June 2000, Hamburg, Germany | Nucl.Instrum.Meth.A472:22-29,2001 | 10.1016/S0168-9002(01)01158-5 | null | hep-ph | null | A review of results on top quark physics expected at the Photon Linear
Colliders is presented.
| [
{
"created": "Fri, 8 Sep 2000 14:23:45 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Boos",
"E. E.",
""
]
] | A review of results on top quark physics expected at the Photon Linear Colliders is presented. |
2403.09144 | Adrian Irles | A. Irles (1), J.P. M\'arquez (1), R. P\"oschl (2), F. Richard (2), A.
Saibel (1), H. Yamamoto (1), N. Yamatsu (3 and 4) ((1) IFIC, Universitat de
Val\`encia and CSIC, C./ Catedr\'atico Jos\'e Beltr\'an 2, Paterna, Spain,
(2) Universit\'e Paris-Saclay, CNRS/IN2P3, IJCLab, Orgsay, France, (3)
Department of Physics, National Taiwan University, Taipei, Taiwan, R.O.C, (4)
Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa
Oiwakecho, Sakyo-ku, Kyoto, Japan) | Probing gauge-Higgs Unification models at the ILC with quark-antiquark
forward-backward asymmetry at center-of-mass energies above the Z mass | null | Eur. Phys. J. C 84, 537 (2024) | 10.1140/epjc/s10052-024-12918-z | ILD-PHYS-2024-001 | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | The International Linear Collider (ILC) will allow the precise study of
$e^{-}e^{+}\rightarrow q\bar{q}$ interactions at different center-of-mass
energies from the $Z$-pole to 1 TeV. In this paper, we discuss the experimental
prospects for measuring differential observables in $e^{-}e^{+}\rightarrow
b\bar{b}$ and $e^{-}e^{+}\rightarrow c\bar{c}$ at the ILC baseline energies,
250 and 500 GeV. The study is based on full simulation and reconstruction of
the International Large Detector (ILD) concept. Two gauge-Higgs unification
models predicting new high-mass resonances beyond the Standard Model are
discussed. These models predict sizable deviations of the forward-backward
observables at the ILC running above the $Z$ mass and with longitudinally
polarized electron and positron beams. The ability of the ILC to probe these
models via high-precision measurements of the forward-backward asymmetry is
discussed. Alternative scenarios at other energies and beam polarization
schemes are also discussed, extrapolating the estimated uncertainties from the
two baseline scenarios.
| [
{
"created": "Thu, 14 Mar 2024 07:43:41 GMT",
"version": "v1"
},
{
"created": "Wed, 29 May 2024 08:58:32 GMT",
"version": "v2"
},
{
"created": "Fri, 31 May 2024 13:53:39 GMT",
"version": "v3"
}
] | 2024-06-03 | [
[
"Irles",
"A.",
"",
"3 and 4"
],
[
"Márquez",
"J. P.",
"",
"3 and 4"
],
[
"Pöschl",
"R.",
"",
"3 and 4"
],
[
"Richard",
"F.",
"",
"3 and 4"
],
[
"Saibel",
"A.",
"",
"3 and 4"
],
[
"Yamamoto",
"H.",
"",
"3 and 4"
],
[
"Yamatsu",
"N.",
"",
"3 and 4"
]
] | The International Linear Collider (ILC) will allow the precise study of $e^{-}e^{+}\rightarrow q\bar{q}$ interactions at different center-of-mass energies from the $Z$-pole to 1 TeV. In this paper, we discuss the experimental prospects for measuring differential observables in $e^{-}e^{+}\rightarrow b\bar{b}$ and $e^{-}e^{+}\rightarrow c\bar{c}$ at the ILC baseline energies, 250 and 500 GeV. The study is based on full simulation and reconstruction of the International Large Detector (ILD) concept. Two gauge-Higgs unification models predicting new high-mass resonances beyond the Standard Model are discussed. These models predict sizable deviations of the forward-backward observables at the ILC running above the $Z$ mass and with longitudinally polarized electron and positron beams. The ability of the ILC to probe these models via high-precision measurements of the forward-backward asymmetry is discussed. Alternative scenarios at other energies and beam polarization schemes are also discussed, extrapolating the estimated uncertainties from the two baseline scenarios. |
2011.14026 | Craig Roberts | Chen Chen, Christian S. Fischer, Craig D. Roberts and Jorge Segovia | Form Factors of the Nucleon Axial Current | 8 pages, 6 figures, 2 tables. Accepted for publication in Phys. Lett.
B | null | 10.1016/j.physletb.2021.136150 | NJU-INP 027/20 | hep-ph hep-ex hep-lat nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A symmetry-preserving Poincar\'e-covariant quark+diquark Faddeev equation
treatment of the nucleon is used to deliver parameter-free predictions for the
nucleon's axial and induced pseudoscalar form factors, $G_A$ and $G_P$,
respectively. The result for $G_A$ can reliably be represented by a dipole form
factor characterised by an axial charge $g_A=G_A(0)=1.25(3)$ and a mass-scale
$M_A = 1.23(3) m_N$, where $m_N$ is the nucleon mass; and regarding $G_P$, the
induced pseudoscalar charge $g_p^\ast = 8.80(23)$, the ratio $g_p^\ast/g_A =
7.04(22)$, and the pion pole dominance Ansatz is found to provide a reliable
estimate of the directly computed result. The ratio of flavour-separated quark
axial charges is also calculated: $g_A^d/g_A^u=-0.16(2)$. This value expresses
a marked suppression of the size of the $d$-quark component relative to that
found in nonrelativistic quark models and owes to the presence of strong
diquark correlations in the nucleon Faddeev wave function -- both scalar and
axial-vector, with the scalar diquark being dominant. The predicted form for
$G_A$ should provide a sound foundation for analyses of the neutrino-nucleus
and antineutrino-nucleus cross-sections that are relevant to modern accelerator
neutrino experiments.
| [
{
"created": "Fri, 27 Nov 2020 23:13:30 GMT",
"version": "v1"
},
{
"created": "Mon, 15 Feb 2021 11:19:40 GMT",
"version": "v2"
}
] | 2021-03-17 | [
[
"Chen",
"Chen",
""
],
[
"Fischer",
"Christian S.",
""
],
[
"Roberts",
"Craig D.",
""
],
[
"Segovia",
"Jorge",
""
]
] | A symmetry-preserving Poincar\'e-covariant quark+diquark Faddeev equation treatment of the nucleon is used to deliver parameter-free predictions for the nucleon's axial and induced pseudoscalar form factors, $G_A$ and $G_P$, respectively. The result for $G_A$ can reliably be represented by a dipole form factor characterised by an axial charge $g_A=G_A(0)=1.25(3)$ and a mass-scale $M_A = 1.23(3) m_N$, where $m_N$ is the nucleon mass; and regarding $G_P$, the induced pseudoscalar charge $g_p^\ast = 8.80(23)$, the ratio $g_p^\ast/g_A = 7.04(22)$, and the pion pole dominance Ansatz is found to provide a reliable estimate of the directly computed result. The ratio of flavour-separated quark axial charges is also calculated: $g_A^d/g_A^u=-0.16(2)$. This value expresses a marked suppression of the size of the $d$-quark component relative to that found in nonrelativistic quark models and owes to the presence of strong diquark correlations in the nucleon Faddeev wave function -- both scalar and axial-vector, with the scalar diquark being dominant. The predicted form for $G_A$ should provide a sound foundation for analyses of the neutrino-nucleus and antineutrino-nucleus cross-sections that are relevant to modern accelerator neutrino experiments. |
hep-ph/0606009 | Stephan J. Huber | Stephan J. Huber | Electroweak Baryogenesis in a Two-Higgs Doublet Model | 5 pages, 2 figures. Proceedings of Moriond 2006, Electroweak Session.
11-18 March, La Thuile (Italy) | null | null | null | hep-ph | null | Electroweak baryogenesis fails in the SM because of too small CP violation
and the lack of a strong first-order phase transition. It has been shown that
supersymmetric models allow for successful baryogenesis, where the Higgsinos
play an important role in the transport processes that generate the asymmetry.
I will demonstrate that also non-supersymmetric models can provide the observed
baryon asymmetry. The top quark takes the role of the Higgsinos. Focusing on
the two-Higgs doublet model, I will discuss details of the phase transition and
consequences for Higgs physics and EDM searches.
| [
{
"created": "Thu, 1 Jun 2006 13:50:07 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Huber",
"Stephan J.",
""
]
] | Electroweak baryogenesis fails in the SM because of too small CP violation and the lack of a strong first-order phase transition. It has been shown that supersymmetric models allow for successful baryogenesis, where the Higgsinos play an important role in the transport processes that generate the asymmetry. I will demonstrate that also non-supersymmetric models can provide the observed baryon asymmetry. The top quark takes the role of the Higgsinos. Focusing on the two-Higgs doublet model, I will discuss details of the phase transition and consequences for Higgs physics and EDM searches. |
hep-ph/0301190 | A. V. Luchinsky | A. V. Luchinsky | On double $1^{--}$ charmonium production through two-photon $\e^+ e^-$
annihilation at $\sqrt{s}=10.6 GeV$ | 4 pages, 2 figures; minor changes | null | null | null | hep-ph | null | Recent measurements of the Belle Collaboration of the exclusive production of
two charmonia in the $e^+e^-$ annihilation differ substantially from
theoretical predictions. Recently it was suggested that a significant part of
this discrepancy can be explained by the process $e^2e^- --> 2J/psi$ and value
for its cross-section was published. In this paper it is shown, that these
results are incorrect and the values for the cross-sections of the production
of different vector charmonia are presented.
| [
{
"created": "Wed, 22 Jan 2003 14:22:10 GMT",
"version": "v1"
},
{
"created": "Sun, 26 Jan 2003 12:47:49 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Luchinsky",
"A. V.",
""
]
] | Recent measurements of the Belle Collaboration of the exclusive production of two charmonia in the $e^+e^-$ annihilation differ substantially from theoretical predictions. Recently it was suggested that a significant part of this discrepancy can be explained by the process $e^2e^- --> 2J/psi$ and value for its cross-section was published. In this paper it is shown, that these results are incorrect and the values for the cross-sections of the production of different vector charmonia are presented. |
hep-ph/9906532 | Schafer | A. Sch\"afer | Physics for a Polarized Electron-Nucleon/Nucleus-Collider | Invited Talk at EPIC-99, Bloomington, Indiana, 8.4.-11.4.99; Latex 15
pages; 6 figures | null | null | null | hep-ph | null | A number of physics arguments for a high-luminosity high energy polarized
Electron- Nucleon/Nucleus-Collider (i.e. with a luminosity of at least 10^{33}
cm^{-2} sec^{-1} and an invariant energy squarred of at least s >= 100 GeV^2)
are presented. The main purpose of this machine would be generally speaking the
investigation of QCD beyond the twist-2 level respectively of nuclear physics
beyond the level of 'effective' models. Specific topics are: twist-2 and
twist-3 spin-asymmetries as probes of both the internal hadron structure and
the hadronization process, Off-Forward-Parton-Distributions as a new dimension
of QCD-physics, nuclear effects for the nucleon structure and nuclear effects
for QCD-dynamics in nuclei. The last two topics are also of direct relevance
for high-energy heavy-ion-collisons. We conclude that the need for such a
collider is clear, if nuclear physics is to continue its development towards a
comprehensive understanding of QCD phenomena.
| [
{
"created": "Tue, 29 Jun 1999 10:32:05 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Schäfer",
"A.",
""
]
] | A number of physics arguments for a high-luminosity high energy polarized Electron- Nucleon/Nucleus-Collider (i.e. with a luminosity of at least 10^{33} cm^{-2} sec^{-1} and an invariant energy squarred of at least s >= 100 GeV^2) are presented. The main purpose of this machine would be generally speaking the investigation of QCD beyond the twist-2 level respectively of nuclear physics beyond the level of 'effective' models. Specific topics are: twist-2 and twist-3 spin-asymmetries as probes of both the internal hadron structure and the hadronization process, Off-Forward-Parton-Distributions as a new dimension of QCD-physics, nuclear effects for the nucleon structure and nuclear effects for QCD-dynamics in nuclei. The last two topics are also of direct relevance for high-energy heavy-ion-collisons. We conclude that the need for such a collider is clear, if nuclear physics is to continue its development towards a comprehensive understanding of QCD phenomena. |
0901.3831 | Helmut Satz | Louis Kluberg and Helmut Satz | Color Deconfinement and Charmonium Production in Nuclear Collisions | 62 pages, 86 figures | null | 10.1007/978-3-642-01539-7_13 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In statistical QCD, color deconfinement and the properties of the quark-gluon
plasma determine the in-medium behavior of heavy quark bound states. In high
energy nuclear collisions, charmonia probe the partonic medium produced in the
early stages of the interaction. We survey the present theoretical status and
provide a critical evaluation of the charmonium production measurements in
experiments at the CERN-SPS and the BNL-RHIC.
| [
{
"created": "Mon, 26 Jan 2009 14:35:27 GMT",
"version": "v1"
}
] | 2019-10-16 | [
[
"Kluberg",
"Louis",
""
],
[
"Satz",
"Helmut",
""
]
] | In statistical QCD, color deconfinement and the properties of the quark-gluon plasma determine the in-medium behavior of heavy quark bound states. In high energy nuclear collisions, charmonia probe the partonic medium produced in the early stages of the interaction. We survey the present theoretical status and provide a critical evaluation of the charmonium production measurements in experiments at the CERN-SPS and the BNL-RHIC. |
0912.3620 | Walter Schmidt-Parzefall | Walter Schmidt-Parzefall | The Neutrino Oscillation Amplitudes | lecture note | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A consistent description of the results of the neutrino oscillation
experiments carried out so far can be obtained from three basic properties of
neutrinos and the parameters of the Hamiltonian matrix. Using these basic
neutrino properties, an exact relation for the oscillation amplitudes of moving
neutrinos is derived.
| [
{
"created": "Fri, 18 Dec 2009 09:36:48 GMT",
"version": "v1"
}
] | 2009-12-21 | [
[
"Schmidt-Parzefall",
"Walter",
""
]
] | A consistent description of the results of the neutrino oscillation experiments carried out so far can be obtained from three basic properties of neutrinos and the parameters of the Hamiltonian matrix. Using these basic neutrino properties, an exact relation for the oscillation amplitudes of moving neutrinos is derived. |
2310.05665 | Simone Devoto | Simone Devoto | $t\bar tH$ production in NNLO QCD | Contribution to the 34th Rencontres de Blois on Particle Physics and
Cosmology (Blois 2023) | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this contribution we present our recent computation of the NNLO QCD
corrections to the production of a Higgs boson associated with a top-antitop
quark pair. This process is of great importance since it allows for a direct
measurement of the top-quark Yukawa coupling, and the inclusion of NNLO
corrections is crucial in order to provide theory predictions with an
uncertainty competitive with the projected accuracy of the experimental
measurements at the end of the high-luminosity phase of the LHC.
| [
{
"created": "Mon, 9 Oct 2023 12:33:31 GMT",
"version": "v1"
}
] | 2023-10-10 | [
[
"Devoto",
"Simone",
""
]
] | In this contribution we present our recent computation of the NNLO QCD corrections to the production of a Higgs boson associated with a top-antitop quark pair. This process is of great importance since it allows for a direct measurement of the top-quark Yukawa coupling, and the inclusion of NNLO corrections is crucial in order to provide theory predictions with an uncertainty competitive with the projected accuracy of the experimental measurements at the end of the high-luminosity phase of the LHC. |
1611.06374 | Takayuki Matsuki | Yubing Dong, Qi-Fang L\"u, Takayuki Matsuki | String point of view for heavy-light mesons | 4 pages, 5 figures, talk at XII Quark Confinement and the Hadron
Spectrum | null | 10.1051/epjconf/201713706016 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An approximate rotational symmetry of a heavy-light meson is viewed from a
string picture. Using a simple string configuration, we derive a formula,
$(M-m_c)^2=\pi\sigma L$, whose coefficient of the r.h.s. is just 1/2 of that of
a light meson with two light quarks. A numerical plot is obtained for $D$
mesons of experimental data as well as several theoretical models, which shows
good agreement with this formula.
| [
{
"created": "Sat, 19 Nov 2016 14:58:14 GMT",
"version": "v1"
}
] | 2017-04-05 | [
[
"Dong",
"Yubing",
""
],
[
"Lü",
"Qi-Fang",
""
],
[
"Matsuki",
"Takayuki",
""
]
] | An approximate rotational symmetry of a heavy-light meson is viewed from a string picture. Using a simple string configuration, we derive a formula, $(M-m_c)^2=\pi\sigma L$, whose coefficient of the r.h.s. is just 1/2 of that of a light meson with two light quarks. A numerical plot is obtained for $D$ mesons of experimental data as well as several theoretical models, which shows good agreement with this formula. |
1103.2571 | Pyungwon Ko | Taeil Hur and P. Ko | Scale invariant extension of the standard model with strongly
interacting hidden sector | Accepted for publication in Phys. Rev. Lett | Phys.Rev.Lett.106:141802,2011 | 10.1103/PhysRevLett.106.141802 | KIAS Preprint: P11010 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a scale invariant extension of the standard model with new
QCD-like strong interaction in the hidden sector. A scale $\Lambda_H$ is
dynamically generated in the hidden sector by dimensional transmutation, and
chiral symmetry breaking occurs in the hidden sector. This scale is transmitted
to the SM sector by a real singlet scalar messenger S, and can trigger
electroweak symmetry breaking (EWSB). Thus all the mass scales in this model
arises from the hidden sector scale $\Lambda_H$ which has quantum mechanical
origin. Furthermore the lightest hadrons in the hidden sector is stable by the
flavor conservation of the hidden sector strong interaction, could be the cold
dark matter (CDM). We study collider phenomenology, and relic density and
direct detection rates of the CDM of this model.
| [
{
"created": "Mon, 14 Mar 2011 01:36:10 GMT",
"version": "v1"
}
] | 2011-04-20 | [
[
"Hur",
"Taeil",
""
],
[
"Ko",
"P.",
""
]
] | We present a scale invariant extension of the standard model with new QCD-like strong interaction in the hidden sector. A scale $\Lambda_H$ is dynamically generated in the hidden sector by dimensional transmutation, and chiral symmetry breaking occurs in the hidden sector. This scale is transmitted to the SM sector by a real singlet scalar messenger S, and can trigger electroweak symmetry breaking (EWSB). Thus all the mass scales in this model arises from the hidden sector scale $\Lambda_H$ which has quantum mechanical origin. Furthermore the lightest hadrons in the hidden sector is stable by the flavor conservation of the hidden sector strong interaction, could be the cold dark matter (CDM). We study collider phenomenology, and relic density and direct detection rates of the CDM of this model. |
hep-ph/0112360 | Daniel J. H. Chung | Daniel J. H. Chung and Thomas Dent | Standard Model baryogenesis through four-fermion operators in
braneworlds | 39 pages, 5 figures v2: typos, presentational changes, references and
acknowledgments added | Phys.Rev. D66 (2002) 023501 | 10.1103/PhysRevD.66.023501 | MCTP-01-64, CERN-TH/2002-002 | hep-ph astro-ph hep-th | null | We study a new baryogenesis scenario in a class of braneworld models with low
fundamental scale, which typically have difficulty with baryogenesis. The
scenario is characterized by its minimal nature: the field content is that of
the Standard Model and all interactions consistent with the gauge symmetry are
admitted. Baryon number is violated via a dimension-6 proton decay operator,
suppressed today by the mechanism of quark-lepton separation in extra
dimensions; we assume that this operator was unsuppressed in the early Universe
due to a time-dependent quark-lepton separation. The source of CP violation is
the CKM matrix, in combination with the dimension-6 operators. We find that
almost independently of cosmology, sufficient baryogenesis is nearly impossible
in such a scenario if the fundamental scale is above 100 TeV, as required by an
unsuppressed neutron-antineutron oscillation operator. The only exception
producing sufficient baryon asymmetry is a scenario involving
out-of-equilibrium c quarks interacting with equilibrium b quarks.
| [
{
"created": "Sun, 30 Dec 2001 07:56:11 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Jan 2002 16:53:30 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Chung",
"Daniel J. H.",
""
],
[
"Dent",
"Thomas",
""
]
] | We study a new baryogenesis scenario in a class of braneworld models with low fundamental scale, which typically have difficulty with baryogenesis. The scenario is characterized by its minimal nature: the field content is that of the Standard Model and all interactions consistent with the gauge symmetry are admitted. Baryon number is violated via a dimension-6 proton decay operator, suppressed today by the mechanism of quark-lepton separation in extra dimensions; we assume that this operator was unsuppressed in the early Universe due to a time-dependent quark-lepton separation. The source of CP violation is the CKM matrix, in combination with the dimension-6 operators. We find that almost independently of cosmology, sufficient baryogenesis is nearly impossible in such a scenario if the fundamental scale is above 100 TeV, as required by an unsuppressed neutron-antineutron oscillation operator. The only exception producing sufficient baryon asymmetry is a scenario involving out-of-equilibrium c quarks interacting with equilibrium b quarks. |
1204.1021 | Arcadi Santamaria | Alberto Aparici, Juan Herrero-Garc\'ia, Nuria Rius, Arcadi Santamaria | On the nature of the fourth generation neutrino and its implications | To be published. Few typos corrected, references updated | null | 10.1007/JHEP07(2012)030 | IFIC/12-22; FTUV-12-0404 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the neutrino sector of a Standard Model with four generations.
While the three light neutrinos can obtain their masses from a variety of
mechanisms with or without new neutral fermions, fourth-generation neutrinos
need at least one new relatively light right-handed neutrino. If lepton number
is not conserved this neutrino must have a Majorana mass term whose size
depends on the underlying mechanism for lepton number violation. Majorana
masses for the fourth generation neutrinos induce relative large two-loop
contributions to the light neutrino masses which could be even larger than the
cosmological bounds. This sets strong limits on the mass parameters and mixings
of the fourth generation neutrinos.
| [
{
"created": "Wed, 4 Apr 2012 18:10:10 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Jul 2012 18:54:38 GMT",
"version": "v2"
}
] | 2015-06-04 | [
[
"Aparici",
"Alberto",
""
],
[
"Herrero-García",
"Juan",
""
],
[
"Rius",
"Nuria",
""
],
[
"Santamaria",
"Arcadi",
""
]
] | We consider the neutrino sector of a Standard Model with four generations. While the three light neutrinos can obtain their masses from a variety of mechanisms with or without new neutral fermions, fourth-generation neutrinos need at least one new relatively light right-handed neutrino. If lepton number is not conserved this neutrino must have a Majorana mass term whose size depends on the underlying mechanism for lepton number violation. Majorana masses for the fourth generation neutrinos induce relative large two-loop contributions to the light neutrino masses which could be even larger than the cosmological bounds. This sets strong limits on the mass parameters and mixings of the fourth generation neutrinos. |
1202.6580 | Konstantin Matchev | K. Matchev, R. Remington | Updated templates for the interpretation of LHC results on supersymmetry
in the context of mSUGRA | added references; 13 pages, 18 figures, root and C macros available
as ancillary files with this submission | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this short note, we describe the preparation of updated templates for the
interpretation of SUSY results from the LHC in the context of mSUGRA. The
standard (m_0,m_{1/2}) plane is shown for fixed mu > 0 and m_t = 173.2 GeV. Two
scenarios are considered: (1) A_0 = 0 GeV and tan(beta)=10 and (2) A_0 = -500
GeV and tan(beta)=40. In each case, the universal scalar mass parameter m_0
varies in the range [40,3000] GeV, while the universal gaugino mass parameter
m_{1/2} varies in the range [100,1000] GeV. We delineate notable regions in
parameter space, including the region with a charged LSP (stau), the LEP2
reach, and the cosmologically preferred region with 100% neutralino dark
matter. The templates also show mass contours for a few key particles (gluino,
squark and Higgs boson). The mass spectrum is calculated with the
SoftSusy-3.2.4 package, while the neutralino relic density is obtained with
MicrOMEGAs version 2.4.
| [
{
"created": "Wed, 29 Feb 2012 15:50:33 GMT",
"version": "v1"
},
{
"created": "Thu, 24 May 2012 13:55:23 GMT",
"version": "v2"
}
] | 2015-03-20 | [
[
"Matchev",
"K.",
""
],
[
"Remington",
"R.",
""
]
] | In this short note, we describe the preparation of updated templates for the interpretation of SUSY results from the LHC in the context of mSUGRA. The standard (m_0,m_{1/2}) plane is shown for fixed mu > 0 and m_t = 173.2 GeV. Two scenarios are considered: (1) A_0 = 0 GeV and tan(beta)=10 and (2) A_0 = -500 GeV and tan(beta)=40. In each case, the universal scalar mass parameter m_0 varies in the range [40,3000] GeV, while the universal gaugino mass parameter m_{1/2} varies in the range [100,1000] GeV. We delineate notable regions in parameter space, including the region with a charged LSP (stau), the LEP2 reach, and the cosmologically preferred region with 100% neutralino dark matter. The templates also show mass contours for a few key particles (gluino, squark and Higgs boson). The mass spectrum is calculated with the SoftSusy-3.2.4 package, while the neutralino relic density is obtained with MicrOMEGAs version 2.4. |
1610.07745 | Neetika Sharma | Neetika Sharma | Momentum transfer dependence of generalized parton distributions | null | EPJA (2016) | 10.1140/epja/i2016-16338-0 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit the model for parametrization of momentum dependence of nucleon
generalized parton distributions in the light of recent MRST measurements of
parton distribution functions. Our parametrization method with minimum set of
free parameters give a sufficiently good description of data for Dirac and
Pauli electromagnetic form factors of proton and neutron at small and
intermediate values of momentum transfer. We also calculate the GPDs for up and
down quark by decomposing the electromagnetic form factors for nucleon using
the charge and isospin symmetry and also study the evolution of GPDs to a
higher scale. We further investigate the transverse charge densities for both
the unpolarized and transversely polarized nucleon and compare our results with
the Kelly's distribution.
| [
{
"created": "Tue, 25 Oct 2016 06:58:35 GMT",
"version": "v1"
}
] | 2016-12-21 | [
[
"Sharma",
"Neetika",
""
]
] | We revisit the model for parametrization of momentum dependence of nucleon generalized parton distributions in the light of recent MRST measurements of parton distribution functions. Our parametrization method with minimum set of free parameters give a sufficiently good description of data for Dirac and Pauli electromagnetic form factors of proton and neutron at small and intermediate values of momentum transfer. We also calculate the GPDs for up and down quark by decomposing the electromagnetic form factors for nucleon using the charge and isospin symmetry and also study the evolution of GPDs to a higher scale. We further investigate the transverse charge densities for both the unpolarized and transversely polarized nucleon and compare our results with the Kelly's distribution. |
2108.10774 | Felix Hekhorn | Alessandro Candido, Stefano Forte and Felix Hekhorn | Can $\overline{MS}$ parton distributions be negative? | 5 pages, 3 figures. Contribution to the XXVIII International Workshop
on Deep-Inelastic Scattering and Related Subjects (DIS2021), April 12-16,
2021. Submission to SciPost Physics Proceedings | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review our recent paper, where we proved Parton distributions functions
(PDFs) to be positive at NLO in the $\overline{MS}$ factorization scheme. We
present some additional material that was useful in completing the steps for
the actual proof, but we won't attempt to report on the full proof, but
referring the reader to the paper itself.
| [
{
"created": "Tue, 24 Aug 2021 14:42:33 GMT",
"version": "v1"
}
] | 2021-08-25 | [
[
"Candido",
"Alessandro",
""
],
[
"Forte",
"Stefano",
""
],
[
"Hekhorn",
"Felix",
""
]
] | We review our recent paper, where we proved Parton distributions functions (PDFs) to be positive at NLO in the $\overline{MS}$ factorization scheme. We present some additional material that was useful in completing the steps for the actual proof, but we won't attempt to report on the full proof, but referring the reader to the paper itself. |
hep-ph/9804310 | Raymond R. Volkas | J P Bowes and R R Volkas | Maximal mixing neutrino models | 23 pages, no figures, ReVTeX. Original version written in March 1997;
revised and updated in March 1998. To appear in J Phys G | J.Phys.G24:1249-1260,1998 | 10.1088/0954-3899/24/7/007 | UM-P-97/09 | hep-ph | null | We account for the solar and atmospheric neutrino problems by introducing
maximal mixing between conventional and sterile neutrino partners. We achieve
this by invoking a seesaw-like mechanism which not only provides us with
maximally mixed neutrino/sterile-neutrino mass eigenstates but also accounts
for the relative suppression of the neutrino masses compared to the charged
fermion masses. In obtaining such an extended seesaw mechanism we are required
to introduce a new U(1) global symmetry together with an extended Higgs sector.
| [
{
"created": "Fri, 17 Apr 1998 01:15:44 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Bowes",
"J P",
""
],
[
"Volkas",
"R R",
""
]
] | We account for the solar and atmospheric neutrino problems by introducing maximal mixing between conventional and sterile neutrino partners. We achieve this by invoking a seesaw-like mechanism which not only provides us with maximally mixed neutrino/sterile-neutrino mass eigenstates but also accounts for the relative suppression of the neutrino masses compared to the charged fermion masses. In obtaining such an extended seesaw mechanism we are required to introduce a new U(1) global symmetry together with an extended Higgs sector. |
hep-ph/0304107 | Xiangdong Ji | Xiangdong Ji, Jian-Ping Ma, and Feng Yuan | Classification and Asymptotic Scaling of Hadron Light-Cone Wave-Function
Amplitudes | 28 pages, no figure | Eur.Phys.J. C33 (2004) 75-90 | 10.1140/epjc/s2003-01563-y | null | hep-ph | null | We classify the hadron light-cone wave-function amplitudes in terms of parton
helicity, orbital angular momentum, and quark flavor and color symmetries. We
show in detail how this is done for the pion, $\rho$ meson, nucleon, and delta
resonance up to and including three partons. For the pion and nucleon, we also
consider four-parton amplitudes. Using the scaling law derived recently, we
show how these amplitudes scale in the limit that all parton transverse momenta
become large.
| [
{
"created": "Fri, 11 Apr 2003 19:09:04 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Ji",
"Xiangdong",
""
],
[
"Ma",
"Jian-Ping",
""
],
[
"Yuan",
"Feng",
""
]
] | We classify the hadron light-cone wave-function amplitudes in terms of parton helicity, orbital angular momentum, and quark flavor and color symmetries. We show in detail how this is done for the pion, $\rho$ meson, nucleon, and delta resonance up to and including three partons. For the pion and nucleon, we also consider four-parton amplitudes. Using the scaling law derived recently, we show how these amplitudes scale in the limit that all parton transverse momenta become large. |
1703.02157 | Zhang Xiao-Bing | Fu-Ping Peng, Xiao-Bing Zhang, Yi Zhang | Magnetic-induced condensate, vortices and vortons in
color-flavor-locked-type matter | 3 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By considering Higgs modes within the Ginzburg-Landau framework, we study
influences of a rotated magnetic field on the color-flavor-locked-type matter
of dense QCD. We demonstrate, in a model-independent way, that a diquark
condensate may be triggered by the magnetic response of rotated-charged Higgs
modes, in addition to the known color-flavor-locked condensate. Moreover, the
condensate is applied to explore formations of vortices in the presence of
external magnetic fields. The superfluid-like vortices are constructed for the
magnetic-induced condensate. In the situation including both kinds of
condensates, the theoretical possibility of vortons is suggested and the
formation condition and the energy stability are investigated semi-classically.
| [
{
"created": "Tue, 7 Mar 2017 00:37:23 GMT",
"version": "v1"
}
] | 2017-03-08 | [
[
"Peng",
"Fu-Ping",
""
],
[
"Zhang",
"Xiao-Bing",
""
],
[
"Zhang",
"Yi",
""
]
] | By considering Higgs modes within the Ginzburg-Landau framework, we study influences of a rotated magnetic field on the color-flavor-locked-type matter of dense QCD. We demonstrate, in a model-independent way, that a diquark condensate may be triggered by the magnetic response of rotated-charged Higgs modes, in addition to the known color-flavor-locked condensate. Moreover, the condensate is applied to explore formations of vortices in the presence of external magnetic fields. The superfluid-like vortices are constructed for the magnetic-induced condensate. In the situation including both kinds of condensates, the theoretical possibility of vortons is suggested and the formation condition and the energy stability are investigated semi-classically. |
hep-ph/9412280 | null | K.D. Lane, F.E. Paige, T. Skwarnicki, and W.J. Womersley | Simulations of Supercollider Physics | 99 pages, Plain TeX (macros included), includes gzipped tar file with
56/60 EPS figures for dvips. Get complete version from
http://penguin.phy.bnl.gov/www/hetpapers.html or
ftp://penguin.phy.bnl.gov/pub/papers/gemreview.ps.Z | Phys.Rept.278:291-371,1997 | 10.1016/S0370-1573(96)00018-X | BNL-61138, BUHEP-94-31, Fermilab Pub-94/392-E | hep-ph hep-ex | null | The Standard Model of particle physics makes it possible to simulate complete
events for physics signatures and their backgrounds in high energy collisions.
Knowledge of how the produced particles interact with the materials in a
detector makes it possible to simulate the response of any particular detector
design to these events and so determine whether the detector could observe the
signal. The combination of these techniques has played an important role in the
design of new detectors, particularly those for hadron supercolliders where the
high rates and small signal cross sections make the experiments very difficult.
The technique is reviewed here and illustrated using the simulations of the GEM
detector proposed for the Superconducting Super Collider. Although the
simulations and results described here are somewhat detector-specific, we
believe that they can serve as a useful model for this component of detector
design for future hadron supercolliders.
| [
{
"created": "Mon, 12 Dec 1994 21:13:41 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Lane",
"K. D.",
""
],
[
"Paige",
"F. E.",
""
],
[
"Skwarnicki",
"T.",
""
],
[
"Womersley",
"W. J.",
""
]
] | The Standard Model of particle physics makes it possible to simulate complete events for physics signatures and their backgrounds in high energy collisions. Knowledge of how the produced particles interact with the materials in a detector makes it possible to simulate the response of any particular detector design to these events and so determine whether the detector could observe the signal. The combination of these techniques has played an important role in the design of new detectors, particularly those for hadron supercolliders where the high rates and small signal cross sections make the experiments very difficult. The technique is reviewed here and illustrated using the simulations of the GEM detector proposed for the Superconducting Super Collider. Although the simulations and results described here are somewhat detector-specific, we believe that they can serve as a useful model for this component of detector design for future hadron supercolliders. |
0903.4249 | Alexander E. Dorokhov | A. E. Dorokhov, M. A. Ivanov, S. G. Kovalenko | Complete structure dependent analysis of the decay $P \to l^{+}l^{-}$ | 11 pages, 1 figure | Phys.Lett.B677:145-149,2009 | 10.1016/j.physletb.2009.05.033 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use the Mellin-Barnes representation in order to improve the theoretical
estimate of mass corrections to the width of light pseudoscalar meson decays
into a lepton pair, $P\to l^{+}l^{-}$ . The full resummation of the terms
$(M^{2}/\Lambda^{2}) ^{n},$ $(m^{2}/M^{2}) ^{n}$and $(m^{2}/\Lambda^{2}) ^{n}$
to the decay amplitude is performed, where $m$ is the lepton mass, $M$ is the
meson mass and $\Lambda\approx m_{\rho}$ is the characteristic scale of the
$P\to \gamma^{\ast}\gamma^{\ast}$ form factor. The total effect of mass
corrections is quite important for $\eta(\eta^{\prime})$ decays. We also
comment on the estimation of the hadronic light-by-light scattering
contribution to the muon anomalous magnetic moment in the chiral perturbation
theory.
| [
{
"created": "Wed, 25 Mar 2009 07:04:38 GMT",
"version": "v1"
}
] | 2009-06-19 | [
[
"Dorokhov",
"A. E.",
""
],
[
"Ivanov",
"M. A.",
""
],
[
"Kovalenko",
"S. G.",
""
]
] | We use the Mellin-Barnes representation in order to improve the theoretical estimate of mass corrections to the width of light pseudoscalar meson decays into a lepton pair, $P\to l^{+}l^{-}$ . The full resummation of the terms $(M^{2}/\Lambda^{2}) ^{n},$ $(m^{2}/M^{2}) ^{n}$and $(m^{2}/\Lambda^{2}) ^{n}$ to the decay amplitude is performed, where $m$ is the lepton mass, $M$ is the meson mass and $\Lambda\approx m_{\rho}$ is the characteristic scale of the $P\to \gamma^{\ast}\gamma^{\ast}$ form factor. The total effect of mass corrections is quite important for $\eta(\eta^{\prime})$ decays. We also comment on the estimation of the hadronic light-by-light scattering contribution to the muon anomalous magnetic moment in the chiral perturbation theory. |
1104.1095 | Vasyl' Rubish V. | V.Yu. Lazur, O.K. Reity, V.V. Rubish | The quasiclassical theory of the Dirac equation with a scalar-vector
interaction and its applications in the theory of heavy-light mesons | 22 pages, 6 figures | Phys.Rev.D83:076003,2011 | 10.1103/PhysRevD.83.076003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a relativistic potential quark model of $D$, $D_s$, $B$, and
$B_s$ mesons in which the light quark motion is described by the Dirac equation
with a scalar-vector interaction and the heavy quark is considered a local
source of the gluon field. The effective interquark interaction is described by
a combination of the perturbative one-gluon exchange potential
$V_{\mathrm{Coul}}(r)=-\xi/r$ and the long-range Lorentz-scalar and
Lorentz-vector linear potentials $S_{\mathrm{l.r.}}(r)=(1-\lambda)(\sigma
r+V_0)$ and $V_{\mathrm{l.r.}}(r)=\lambda(\sigma r+V_0)$, where
$0\leqslant\lambda<1/2$. Within the quasiclassical approximation, we obtain
simple asymptotic formulas for the energy and mass spectra and for the mean
radii of $D$, $D_s$, $B$, and $B_s$ mesons, which ensure a high accuracy of
calculations even for states with the radial quantum number $n_r\sim 1$. We
show that the fine structure of P-wave states in heavy-light mesons is
primarily sensitive to the choice of two parameters: the strong-coupling
constant $\alpha_s$ and the coefficient $\lambda$ of mixing of the long-range
scalar and vector potentials $S_{\mathrm{l.r.}}(r)$ and $V_{\mathrm{l.r.}}(r)$.
The quasiclassical formulas for asymptotic coefficients of wave function at
zero and infinity are obtained.
| [
{
"created": "Wed, 6 Apr 2011 13:38:52 GMT",
"version": "v1"
}
] | 2015-03-19 | [
[
"Lazur",
"V. Yu.",
""
],
[
"Reity",
"O. K.",
""
],
[
"Rubish",
"V. V.",
""
]
] | We construct a relativistic potential quark model of $D$, $D_s$, $B$, and $B_s$ mesons in which the light quark motion is described by the Dirac equation with a scalar-vector interaction and the heavy quark is considered a local source of the gluon field. The effective interquark interaction is described by a combination of the perturbative one-gluon exchange potential $V_{\mathrm{Coul}}(r)=-\xi/r$ and the long-range Lorentz-scalar and Lorentz-vector linear potentials $S_{\mathrm{l.r.}}(r)=(1-\lambda)(\sigma r+V_0)$ and $V_{\mathrm{l.r.}}(r)=\lambda(\sigma r+V_0)$, where $0\leqslant\lambda<1/2$. Within the quasiclassical approximation, we obtain simple asymptotic formulas for the energy and mass spectra and for the mean radii of $D$, $D_s$, $B$, and $B_s$ mesons, which ensure a high accuracy of calculations even for states with the radial quantum number $n_r\sim 1$. We show that the fine structure of P-wave states in heavy-light mesons is primarily sensitive to the choice of two parameters: the strong-coupling constant $\alpha_s$ and the coefficient $\lambda$ of mixing of the long-range scalar and vector potentials $S_{\mathrm{l.r.}}(r)$ and $V_{\mathrm{l.r.}}(r)$. The quasiclassical formulas for asymptotic coefficients of wave function at zero and infinity are obtained. |
hep-ph/0703212 | Yutaka Sakamura | Yutaka Hosotani and Yutaka Sakamura | Anomalous Higgs Couplings in the $SO(5)\times U(1)_{B-L}$ Gauge-Higgs
Unification in Warped Spacetime | 34 pages, 3 eps files, published version | Prog.Theor.Phys.118:935-968,2007 | 10.1143/PTP.118.935 | OU-HET 577/2007 | hep-ph | null | The gauge couplings $WWZ$, $WWWW$, and $WWZZ$ in the gauge-Higgs unification
scenario in the Randall-Sundrum warped spacetime remain almost universal as in
the standard model, but substantial deviation results for the Higgs couplings.
In the $SO(5)\times U(1)_{B-L}$ model, the couplings $WWH$ and $ZZH$ are
suppressed by a factor $\cos \theta_H$ from the values in the standard model,
while the bare couplings $WWHH$ and $ZZHH$ are suppressed by a factor
$1-(2/3)\sin^2 \theta_H$. Here $\theta_H$ is the Yang-Mills AB phase (Wilson
line phase) along the fifth dimension, which characterizes the electroweak
symmetry breaking. The suppression can be used to test the gauge-Higgs
unification scenario at LHC and ILC. It is also shown that the $WWZ$ coupling
in flat spacetime deviates from the standard model value at moderate values of
$\theta_H$, contradicting with the LEP2 data.
| [
{
"created": "Tue, 20 Mar 2007 06:44:51 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Aug 2007 09:18:09 GMT",
"version": "v2"
},
{
"created": "Thu, 8 Nov 2007 06:44:52 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Hosotani",
"Yutaka",
""
],
[
"Sakamura",
"Yutaka",
""
]
] | The gauge couplings $WWZ$, $WWWW$, and $WWZZ$ in the gauge-Higgs unification scenario in the Randall-Sundrum warped spacetime remain almost universal as in the standard model, but substantial deviation results for the Higgs couplings. In the $SO(5)\times U(1)_{B-L}$ model, the couplings $WWH$ and $ZZH$ are suppressed by a factor $\cos \theta_H$ from the values in the standard model, while the bare couplings $WWHH$ and $ZZHH$ are suppressed by a factor $1-(2/3)\sin^2 \theta_H$. Here $\theta_H$ is the Yang-Mills AB phase (Wilson line phase) along the fifth dimension, which characterizes the electroweak symmetry breaking. The suppression can be used to test the gauge-Higgs unification scenario at LHC and ILC. It is also shown that the $WWZ$ coupling in flat spacetime deviates from the standard model value at moderate values of $\theta_H$, contradicting with the LEP2 data. |
1412.4836 | J. A. R. Cembranos | Alfredo Aranda, and Jose A. R. Cembranos | The right generations | 5 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Standard Model has three generations of fermions and although it does not
contain any explicit reason for this, the existence of additional generations
is now very constrained by experiment. Present measurements are saturating
perturbative unitarity limits. The main idea of this work is to show that those
restrictions can be relaxed if the new generations experience different
interactions. This new setup leads to the presence of additional stable degrees
of freedom that give rise to a very rich phenomenology for cosmology,
astrophysics and particle physics. The stability is a consequence of the
conservation of new accidental baryon and lepton numbers. We present an
explicit example by introducing a fourth generation charged under a new
$SU(2)_R$ gauge interaction instead of the standard $SU(2)_L$. The simplest
implementations lead to models that contain stable quarks, leptons and
neutrinos. We show that these new particles can have a wide range of masses
within a non-standard cosmological set-up. Indeed, the new neutrinos (and {\it
neutral leptons}) constitute viable dark matter candidates if they are the
lightest of these new particles.
| [
{
"created": "Mon, 15 Dec 2014 23:34:42 GMT",
"version": "v1"
}
] | 2014-12-17 | [
[
"Aranda",
"Alfredo",
""
],
[
"Cembranos",
"Jose A. R.",
""
]
] | The Standard Model has three generations of fermions and although it does not contain any explicit reason for this, the existence of additional generations is now very constrained by experiment. Present measurements are saturating perturbative unitarity limits. The main idea of this work is to show that those restrictions can be relaxed if the new generations experience different interactions. This new setup leads to the presence of additional stable degrees of freedom that give rise to a very rich phenomenology for cosmology, astrophysics and particle physics. The stability is a consequence of the conservation of new accidental baryon and lepton numbers. We present an explicit example by introducing a fourth generation charged under a new $SU(2)_R$ gauge interaction instead of the standard $SU(2)_L$. The simplest implementations lead to models that contain stable quarks, leptons and neutrinos. We show that these new particles can have a wide range of masses within a non-standard cosmological set-up. Indeed, the new neutrinos (and {\it neutral leptons}) constitute viable dark matter candidates if they are the lightest of these new particles. |
hep-ph/0308011 | Amilcar Benjamim Ribeiro Rodrigues | J. Dias de Deus and A. Rodrigues | Transverse Momentum Fluctuations from Clustering and Percolation of
Strings | 4 pages, 3 figures | null | null | null | hep-ph | null | Transverse momentum fluctuations can be understood as resulting from
clustering of strings or partons. Data allows to distinguish clustering without
percolation, from clustering with percolation. Percolation is clearly favored
by data.
| [
{
"created": "Fri, 1 Aug 2003 11:50:50 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"de Deus",
"J. Dias",
""
],
[
"Rodrigues",
"A.",
""
]
] | Transverse momentum fluctuations can be understood as resulting from clustering of strings or partons. Data allows to distinguish clustering without percolation, from clustering with percolation. Percolation is clearly favored by data. |
0809.3873 | Yun Guo | Yun Guo | Gluon Propagator and Heavy Quark Potential in an Anisotropic QCD Plasma | 4 pages, to be published in the proceedings of SEWM 2008, Nucl. Phys.
A, in print | Nucl.Phys.A820:275c-278c,2009 | 10.1016/j.nuclphysa.2009.01.068 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The hard-loop resummed propagator in an anisotropic QCD plasma in general
linear gauges are computed. We get the explicit expressions of the gluon
propagator in covariant gauge, Coulomb gauge and temporal axial gauge.
Considering one gluon exchange, the potential between heavy quarks is defined
through the Fourier transform of the static propagator. We find that the
potential exhibits angular dependence and that there is stronger attraction on
distance scales on the order of the inverse Debye mass for quark pairs aligned
along the direction of anisotropy than for transverse alignment.
| [
{
"created": "Tue, 23 Sep 2008 09:44:51 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Guo",
"Yun",
""
]
] | The hard-loop resummed propagator in an anisotropic QCD plasma in general linear gauges are computed. We get the explicit expressions of the gluon propagator in covariant gauge, Coulomb gauge and temporal axial gauge. Considering one gluon exchange, the potential between heavy quarks is defined through the Fourier transform of the static propagator. We find that the potential exhibits angular dependence and that there is stronger attraction on distance scales on the order of the inverse Debye mass for quark pairs aligned along the direction of anisotropy than for transverse alignment. |
1601.04154 | Gernot Eichmann | Gernot Eichmann | Towards a microscopic understanding of nucleon polarizabilities | 6 pages, 5 figures. Proceedings of Light Cone 2015, INFN Frascati,
September 21-25, 2015 | null | 10.1007/s00601-016-1046-8 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We outline a microscopic framework to calculate nucleon Compton scattering
from the level of quarks and gluons within the covariant Faddeev approach. We
explain the connection with hadronic expansions of the Compton scattering
amplitude and discuss the obstacles in maintaining electromagnetic gauge
invariance. Finally we give preliminary results for the nucleon
polarizabilities.
| [
{
"created": "Sat, 16 Jan 2016 10:55:00 GMT",
"version": "v1"
}
] | 2016-03-23 | [
[
"Eichmann",
"Gernot",
""
]
] | We outline a microscopic framework to calculate nucleon Compton scattering from the level of quarks and gluons within the covariant Faddeev approach. We explain the connection with hadronic expansions of the Compton scattering amplitude and discuss the obstacles in maintaining electromagnetic gauge invariance. Finally we give preliminary results for the nucleon polarizabilities. |
hep-ph/0204224 | Gregory W. Carter | D. M. Ostrovsky, G. W. Carter, and E. V. Shuryak | Forced Tunneling and Turning State Explosion in Pure Yang-Mills Theory | 17 pages, 17 figures, revtex, references amended | Phys.Rev. D66 (2002) 036004 | 10.1103/PhysRevD.66.036004 | NT@UW-02-008 | hep-ph nucl-th | null | We consider forced tunneling in QCD, described semiclassically by
instanton-antiinstanton field configurations. By separating topologically
different minima we obtain details of the effective potential and study the
turning states, which are similar to the sphaleron solution in electroweak
theory. These states are alternatively derived as minima of the energy under
the constraints of fixed size and Chern-Simons number. We study, both
analytically and numerically, the subsequent evolution of such states by
solving the classical Yang-Mills equations in real time, and find that the
gauge field strength is quickly localized into an expanding shell of radiating
gluons. The relevance to high-energy collisions of hadrons and nuclei is
briefly discussed.
| [
{
"created": "Thu, 18 Apr 2002 16:02:35 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Apr 2002 17:18:34 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Ostrovsky",
"D. M.",
""
],
[
"Carter",
"G. W.",
""
],
[
"Shuryak",
"E. V.",
""
]
] | We consider forced tunneling in QCD, described semiclassically by instanton-antiinstanton field configurations. By separating topologically different minima we obtain details of the effective potential and study the turning states, which are similar to the sphaleron solution in electroweak theory. These states are alternatively derived as minima of the energy under the constraints of fixed size and Chern-Simons number. We study, both analytically and numerically, the subsequent evolution of such states by solving the classical Yang-Mills equations in real time, and find that the gauge field strength is quickly localized into an expanding shell of radiating gluons. The relevance to high-energy collisions of hadrons and nuclei is briefly discussed. |
hep-ph/9506395 | My Account | N. Mavromatos and T. Ruf (for the collaboration: J. Ellis, J. Lopez,
N. Mavromatos, D. Nanopoulos, and the CPLEAR Collaboration) | Experimental tests of CPT symmetry and quantum mechanics at CPLEAR | 20 pages (LaTeX), 2 figures (uuencoded) | null | null | ENSLAPP-A-530/95 | hep-ph hep-th | null | We review a phenomenological parametrization of an open quantum-mechanical
formalism for CPT violation in the neutral kaon system, and constrain the
parameters using fits to recent CPLEAR data.
| [
{
"created": "Thu, 22 Jun 1995 15:16:22 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mavromatos",
"N.",
"",
"for the collaboration: J. Ellis, J. Lopez,\n N. Mavromatos, D. Nanopoulos, and the CPLEAR Collaboration"
],
[
"Ruf",
"T.",
"",
"for the collaboration: J. Ellis, J. Lopez,\n N. Mavromatos, D. Nanopoulos, and the CPLEAR Collaboration"
]
] | We review a phenomenological parametrization of an open quantum-mechanical formalism for CPT violation in the neutral kaon system, and constrain the parameters using fits to recent CPLEAR data. |
1009.5551 | Alexey Kiselev | N.N. Achasov and A.V. Kiselev | Analytical properties of the $\pi\pi$ scattering amplitude and the light
scalar mesons | 8 pages, 6 figures. The talk given by A.V. Kiselev at the
International Seminar "Quarks-2010", Kolomna, Russia, June 6-12, 2010 | null | null | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $\pi\pi$ scattering amplitude with regular analytical properties in the
$s$ complex plane has been constructed. It describes simultaneously the data on
the $\pi\pi$ scattering, $\phi\to\pi^0\pi^0\gamma$ decay and $\pi\pi\to K\bar
K$ reaction. The chiral shielding of the $\sigma (600)$ meson and it's mixing
with the $f_0(980)$ meson are taken into account also. The data agrees with the
four-quark nature of the $\sigma (600)$ and $f_0(980)$ mesons.
The amplitude in the range $-5 m_\pi^2 < s < 0.64$ GeV$^2$ also agrees with
results, obtained on the base of the chiral expansion, dispersion relations and
the Roy equations.
| [
{
"created": "Tue, 28 Sep 2010 12:38:04 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Nov 2010 15:30:07 GMT",
"version": "v2"
}
] | 2010-11-22 | [
[
"Achasov",
"N. N.",
""
],
[
"Kiselev",
"A. V.",
""
]
] | The $\pi\pi$ scattering amplitude with regular analytical properties in the $s$ complex plane has been constructed. It describes simultaneously the data on the $\pi\pi$ scattering, $\phi\to\pi^0\pi^0\gamma$ decay and $\pi\pi\to K\bar K$ reaction. The chiral shielding of the $\sigma (600)$ meson and it's mixing with the $f_0(980)$ meson are taken into account also. The data agrees with the four-quark nature of the $\sigma (600)$ and $f_0(980)$ mesons. The amplitude in the range $-5 m_\pi^2 < s < 0.64$ GeV$^2$ also agrees with results, obtained on the base of the chiral expansion, dispersion relations and the Roy equations. |
1401.7420 | Nodoka Yamanaka | Nodoka Yamanaka, Takahiro M. Doi, Shotaro Imai, Hideo Suganuma | Quark tensor and axial charges within the Schwinger-Dyson formalism | 5 pages, 4 figures, Contribution of proceedings of XV International
Conference on Hadron Spectroscopy-Hadron 2013 (Hadron 2013) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the tensor and axial charges of the quark in the Schwinger-Dyson
formalism of Landau gauge QCD. It is found that the dressed tensor and
isovector axial charges of the quark are suppressed against the bare quark
contribution, and the result agrees qualitatively with the experimental data.
We show that this is due to the superposition of the spin flip of the quark
arising from the successive emission of gluons which dress the vertex. For the
isoscalar quark axial charge, we have analyzed the Schwinger-Dyson equation by
including the leading unquenching quark-loop effect. It is found that the
suppression is more significant, due to the axial anomaly effect.
| [
{
"created": "Wed, 29 Jan 2014 07:19:23 GMT",
"version": "v1"
}
] | 2014-01-30 | [
[
"Yamanaka",
"Nodoka",
""
],
[
"Doi",
"Takahiro M.",
""
],
[
"Imai",
"Shotaro",
""
],
[
"Suganuma",
"Hideo",
""
]
] | We calculate the tensor and axial charges of the quark in the Schwinger-Dyson formalism of Landau gauge QCD. It is found that the dressed tensor and isovector axial charges of the quark are suppressed against the bare quark contribution, and the result agrees qualitatively with the experimental data. We show that this is due to the superposition of the spin flip of the quark arising from the successive emission of gluons which dress the vertex. For the isoscalar quark axial charge, we have analyzed the Schwinger-Dyson equation by including the leading unquenching quark-loop effect. It is found that the suppression is more significant, due to the axial anomaly effect. |
1209.5992 | Kanchan Khemchandani | A. Mart\'inez Torres, K. P. Khemchandani, M. Nielsen, F. S. Navarra | Predicting the existence of a 2.9 GeV $Df_0(980)$ molecular state | Improved error estimation made, which lead to better conclusions.
Version accepted for publication in PRD | null | 10.1103/PhysRevD.87.034025 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A $D$-like meson resonance with mass around 2.9 GeV has been found in the
$DK\bar K$ system using two independent and different model calculations based
on: (1) QCD sum rules and (2) solution of Fadeev equations with input
interactions obtained from effective field theories built by considering both
chiral and heavy quark symmetries. The QCD sum rules have been used to study
the $D_{s^*0}(2317) \bar{K}$ and $D f_0(980)$ molecular currents. A resonance
of mass 2.926 GeV is found with the $D f_0(980)$ current. Although a state in
the $D_{s^*0}(2317) \bar{K}$ current is also obtained, with mass around 2.9
GeV, the coupling of this state is found to be two times weaker than the one
formed in $D f_0(980)$. On the other hand, few-body equations are solved for
the $D K \bar{K}$ system and its coupled channels with the input $t$-matrices
obtained by solving Bethe-Salpeter equations for the $D K$, $D\bar{K}$ and $K
\bar{K}$ subsystems. In this study a $D$-like meson with mass 2.890 GeV and
full width $\sim$ 55 MeV is found to get dynamically generated when $D K
\bar{K}$ gets reorganized as $D f_0(980)$. However, no clear signal appears for
the $D_{s^*0}(2317) \bar{K}$ configuration. The striking similarity between the
results obtained in the two different models indicates strongly towards the
existence of a $D f_0 (980)$ molecule with mass nearly 2.9 GeV.
| [
{
"created": "Wed, 26 Sep 2012 16:32:25 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Feb 2013 20:23:05 GMT",
"version": "v2"
}
] | 2013-03-14 | [
[
"Torres",
"A. Martínez",
""
],
[
"Khemchandani",
"K. P.",
""
],
[
"Nielsen",
"M.",
""
],
[
"Navarra",
"F. S.",
""
]
] | A $D$-like meson resonance with mass around 2.9 GeV has been found in the $DK\bar K$ system using two independent and different model calculations based on: (1) QCD sum rules and (2) solution of Fadeev equations with input interactions obtained from effective field theories built by considering both chiral and heavy quark symmetries. The QCD sum rules have been used to study the $D_{s^*0}(2317) \bar{K}$ and $D f_0(980)$ molecular currents. A resonance of mass 2.926 GeV is found with the $D f_0(980)$ current. Although a state in the $D_{s^*0}(2317) \bar{K}$ current is also obtained, with mass around 2.9 GeV, the coupling of this state is found to be two times weaker than the one formed in $D f_0(980)$. On the other hand, few-body equations are solved for the $D K \bar{K}$ system and its coupled channels with the input $t$-matrices obtained by solving Bethe-Salpeter equations for the $D K$, $D\bar{K}$ and $K \bar{K}$ subsystems. In this study a $D$-like meson with mass 2.890 GeV and full width $\sim$ 55 MeV is found to get dynamically generated when $D K \bar{K}$ gets reorganized as $D f_0(980)$. However, no clear signal appears for the $D_{s^*0}(2317) \bar{K}$ configuration. The striking similarity between the results obtained in the two different models indicates strongly towards the existence of a $D f_0 (980)$ molecule with mass nearly 2.9 GeV. |
hep-ph/9904280 | Sharon Jensen | Stanley J. Brodsky, Johan Rathsman, Carlos Merino | Odderon-Pomeron Interference | 12 pages, 4 figures, Minor corrections, Main results unchanged,
Contribution from photon exchange added, Numerical estimates updated and
uncertainties clarified. To appear in Physics Letters B | Phys.Lett.B461:114-122,1999 | 10.1016/S0370-2693(99)00807-2 | SLAC-PUB-8095 | hep-ph | null | We show that the asymmetry in the fractional energy of charm versus anticharm
jets produced in high energy diffractive photoproduction is sensitive to the
interference of the Odderon $(C = -)$ and Pomeron $(C = +)$ exchange amplitudes
in QCD. We predict the dynamical shape of the asymmetry in a simple model and
estimate its magnitude to be of the order 15% using an Odderon coupling to the
proton which saturates constraints from proton-proton vs. proton-antiproton
elastic scattering. Measurements of this asymmetry at HERA could provide firm
experimental evidence for the presence of Odderon exchange in the high energy
limit of strong interactions.
| [
{
"created": "Thu, 8 Apr 1999 21:03:42 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Jul 1999 21:36:51 GMT",
"version": "v2"
}
] | 2009-09-11 | [
[
"Brodsky",
"Stanley J.",
""
],
[
"Rathsman",
"Johan",
""
],
[
"Merino",
"Carlos",
""
]
] | We show that the asymmetry in the fractional energy of charm versus anticharm jets produced in high energy diffractive photoproduction is sensitive to the interference of the Odderon $(C = -)$ and Pomeron $(C = +)$ exchange amplitudes in QCD. We predict the dynamical shape of the asymmetry in a simple model and estimate its magnitude to be of the order 15% using an Odderon coupling to the proton which saturates constraints from proton-proton vs. proton-antiproton elastic scattering. Measurements of this asymmetry at HERA could provide firm experimental evidence for the presence of Odderon exchange in the high energy limit of strong interactions. |
hep-ph/9502209 | null | T.S.Evans and A.C.Pearson (Imperial College, London) | Thermalisation of Gauge Bosons in the Abelian Higgs Model | 13 pages, latex, 3 eps figures available through anonymous ftp from
ftp://euclid.tp.ph.ic.ac.uk/papers/94-5_16.tex or at
http://euclid.tp.ph.ic.ac.uk/Papers/index.html | Phys.Rev.D55:3748-3755,1997 | 10.1103/PhysRevD.55.3748 | Imperial/TP/94-95/16 | hep-ph | null | The thermalisation rate for long wavelength fluctuations of the gauge field
in the abelian Higgs model is calculated from the imaginary part of the self
energy. The calculation is performed for both the symmetric and symmetry broken
phase of the theory.
| [
{
"created": "Wed, 1 Feb 1995 15:57:48 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Evans",
"T. S.",
"",
"Imperial College, London"
],
[
"Pearson",
"A. C.",
"",
"Imperial College, London"
]
] | The thermalisation rate for long wavelength fluctuations of the gauge field in the abelian Higgs model is calculated from the imaginary part of the self energy. The calculation is performed for both the symmetric and symmetry broken phase of the theory. |
2403.18010 | Andreas Gei{\ss}el | Andreas Gei{\ss}el, Tyler Gorda, Jens Braun | Pressure and speed of sound in two-flavor color-superconducting quark
matter at next-to-leading order | 20 pages, 9 figures, 1 table | Phys. Rev. D 110, 014034 (2024) | 10.1103/PhysRevD.110.014034 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Deconfined quark matter at asymptotically high densities is weakly coupled,
due to the asymptotic freedom of Quantum Chromodynamics. In this weak-coupling
regime, bulk thermodynamic properties of quark matter, assuming a trivial
ground state, are currently known to partial next-to-next-to-next-to-leading
order. However, the ground state at high densities is expected to be a color
superconductor, in which the excitation spectrum of (at least some) quarks
exhibit a gap with a non-perturbative dependence on the strong coupling. In
this work, we calculate the thermodynamic properties of color-superconducting
quark matter at high densities and zero temperature at next-to-leading order
(NLO) in the coupling in the presence of a finite gap. We work in the limit of
two massless quark flavors, which corresponds to deconfined symmetric nuclear
matter, and further assume that the gap is small compared to the quark chemical
potential. In these limits, we find that the NLO corrections to the pressure
and speed of sound are comparable in size to the leading-order effects of the
gap, and further increase both quantities above their values for
non-superconducting quark matter. We also provide a parameterization of the NLO
speed of sound to guide phenomenology in the high-density region, and we
furthermore comment on whether our findings should be expected to extend to the
case of three-flavor quark matter of relevance to neutron stars.
| [
{
"created": "Tue, 26 Mar 2024 18:01:18 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Jul 2024 12:27:52 GMT",
"version": "v2"
}
] | 2024-07-25 | [
[
"Geißel",
"Andreas",
""
],
[
"Gorda",
"Tyler",
""
],
[
"Braun",
"Jens",
""
]
] | Deconfined quark matter at asymptotically high densities is weakly coupled, due to the asymptotic freedom of Quantum Chromodynamics. In this weak-coupling regime, bulk thermodynamic properties of quark matter, assuming a trivial ground state, are currently known to partial next-to-next-to-next-to-leading order. However, the ground state at high densities is expected to be a color superconductor, in which the excitation spectrum of (at least some) quarks exhibit a gap with a non-perturbative dependence on the strong coupling. In this work, we calculate the thermodynamic properties of color-superconducting quark matter at high densities and zero temperature at next-to-leading order (NLO) in the coupling in the presence of a finite gap. We work in the limit of two massless quark flavors, which corresponds to deconfined symmetric nuclear matter, and further assume that the gap is small compared to the quark chemical potential. In these limits, we find that the NLO corrections to the pressure and speed of sound are comparable in size to the leading-order effects of the gap, and further increase both quantities above their values for non-superconducting quark matter. We also provide a parameterization of the NLO speed of sound to guide phenomenology in the high-density region, and we furthermore comment on whether our findings should be expected to extend to the case of three-flavor quark matter of relevance to neutron stars. |
hep-ph/9911311 | Florian Krajewski | J.G. Koerner, F. Krajewski, A.A. Pivovarov | Asymptotic structure of perturbative series for $\tau$ lepton decay
observables: $m_s^2$ corrections | 25 pages | Eur.Phys.J.C14:123-132,2000 | 10.1007/s100520050739 | MZ-TH/99-46 | hep-ph | null | In a previous paper we performed an analysis of asymptotic structure of
perturbation theory series for semileptonic $\tau$-lepton decays in massless
limit. We extend our analysis to the Cabibbo suppressed $\Delta S=1$ decay
modes of the $\tau$ lepton. In particular we address the problem of $m_s^2$
corrections to theoretical formulas. The properties of the asymptotic behavior
of the finite order perturbation theory series for the coefficient functions of
the $m_s^2$ corrections are studied.
| [
{
"created": "Thu, 11 Nov 1999 11:38:59 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Koerner",
"J. G.",
""
],
[
"Krajewski",
"F.",
""
],
[
"Pivovarov",
"A. A.",
""
]
] | In a previous paper we performed an analysis of asymptotic structure of perturbation theory series for semileptonic $\tau$-lepton decays in massless limit. We extend our analysis to the Cabibbo suppressed $\Delta S=1$ decay modes of the $\tau$ lepton. In particular we address the problem of $m_s^2$ corrections to theoretical formulas. The properties of the asymptotic behavior of the finite order perturbation theory series for the coefficient functions of the $m_s^2$ corrections are studied. |
2307.16486 | Anh Dung Le | Tuomas Lappi (1 and 2), Anh Dung Le (1 and 2), Heikki M\"antysaari (1
and 2) ((1) Department of Physics, University of Jyv\"askyl\"a, (2) Helsinki
Institute of Physics) | Rapidity gap distribution of diffractive small-$x_{I\hspace{-0.3em}P}$
events at HERA and at the EIC | 18 pages, 16 figures, 1 table | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We use the Kovchegov-Levin equation to resum contributions of large invariant
mass diffractive final states to diffractive structure functions in the dipole
picture of deep inelastic scattering. For protons we use a (modified)
McLerran-Venugopalan model as the initial condition for the evolution, with
free parameters obtained from fits to the HERA inclusive data. We obtain an
adequate agreement to the HERA diffractive data in the moderately high-mass
regimes when the proton density profile is fitted to the diffractive structure
function data in the low-mass region. The HERA data is found to prefer a proton
shape that is steeper than a Gaussian. The initial conditions are generalized
to the nuclear case using the optical Glauber model. Strong nuclear
modification effects are predicted in diffractive scattering off a nuclear
target in kinematics accessible at the future Electron-Ion collider. In
particular, the Kovchegov-Levin evolution has a strong effect on the Q 2
-dependence of the diffractive cross section.
| [
{
"created": "Mon, 31 Jul 2023 08:31:11 GMT",
"version": "v1"
}
] | 2023-08-01 | [
[
"Lappi",
"Tuomas",
"",
"1 and 2"
],
[
"Le",
"Anh Dung",
"",
"1 and 2"
],
[
"Mäntysaari",
"Heikki",
"",
"1\n and 2"
]
] | We use the Kovchegov-Levin equation to resum contributions of large invariant mass diffractive final states to diffractive structure functions in the dipole picture of deep inelastic scattering. For protons we use a (modified) McLerran-Venugopalan model as the initial condition for the evolution, with free parameters obtained from fits to the HERA inclusive data. We obtain an adequate agreement to the HERA diffractive data in the moderately high-mass regimes when the proton density profile is fitted to the diffractive structure function data in the low-mass region. The HERA data is found to prefer a proton shape that is steeper than a Gaussian. The initial conditions are generalized to the nuclear case using the optical Glauber model. Strong nuclear modification effects are predicted in diffractive scattering off a nuclear target in kinematics accessible at the future Electron-Ion collider. In particular, the Kovchegov-Levin evolution has a strong effect on the Q 2 -dependence of the diffractive cross section. |
hep-ph/9602261 | Sin Kyu Kang | Kyungsik Kang, Sin Kyu Kang | Critical Review of The Electroweak Precision Tests | 10 pages, talk presented by K. Kang at the International Symposium on
Heavy Flavor and Electroweak Theory, Beijing, China, 17 - 19 August 1995.
Plain TeX, uses vanilla.sty, eight.tex, nine.tex and table.tex | null | null | BROWN-HET-1033, BROWN-TA-532 | hep-ph | null | There have been a great deal of works on the precision test of the standard
model (SM) because of the incredibly precise data obtained at the LEP and the
new measurements of $M_W$ and $m_t$ at the Fermilab Tevatron as well as the
recent theoretical progress in the higher order radiative corrections. We will
discuss some of the hidden inputs and theoretical uncertainties involved in
making the predictions of the observables in the SM. From the minimal
$\chi^2$-fit to the experimental Z-decay parameters (with the aid of a modified
ZFITTER program) in a scheme where $M_Z$, $G_{\mu}$ and $\alpha (M_Z)$ are
taken as inputs, we can predict $M_W$ for given values of $m_H$ and $m_t$. The
current world average value of $M_W$ definitely favor nonvanishing electroweak
radiative corrections and is consistent with a heavy $m_t$ as measured by the
recent CDF report but with a heavy Higgs scalar of about 500 GeV within the
context of the minimal SM. The sensitivity of and the errors in the best fit
solutions due to the uncertainties in the gluonic coupling $\alpha_s(M_Z)$ and
$\alpha (M_Z)$ are examined carefully and any trace of new physics beyond the
SM implied by the data, in a particular $R_b$ and $R_c$, is also touched upon.
In addition we discuss how the future precision measurements of $M_W$ and $Z$
decay parameters can determine the Higgs boson mass and distinguish the SM with
radiative corrections from the minimal supersymmetric standard model (MSSM) and
other extended model.
| [
{
"created": "Fri, 9 Feb 1996 03:30:34 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kang",
"Kyungsik",
""
],
[
"Kang",
"Sin Kyu",
""
]
] | There have been a great deal of works on the precision test of the standard model (SM) because of the incredibly precise data obtained at the LEP and the new measurements of $M_W$ and $m_t$ at the Fermilab Tevatron as well as the recent theoretical progress in the higher order radiative corrections. We will discuss some of the hidden inputs and theoretical uncertainties involved in making the predictions of the observables in the SM. From the minimal $\chi^2$-fit to the experimental Z-decay parameters (with the aid of a modified ZFITTER program) in a scheme where $M_Z$, $G_{\mu}$ and $\alpha (M_Z)$ are taken as inputs, we can predict $M_W$ for given values of $m_H$ and $m_t$. The current world average value of $M_W$ definitely favor nonvanishing electroweak radiative corrections and is consistent with a heavy $m_t$ as measured by the recent CDF report but with a heavy Higgs scalar of about 500 GeV within the context of the minimal SM. The sensitivity of and the errors in the best fit solutions due to the uncertainties in the gluonic coupling $\alpha_s(M_Z)$ and $\alpha (M_Z)$ are examined carefully and any trace of new physics beyond the SM implied by the data, in a particular $R_b$ and $R_c$, is also touched upon. In addition we discuss how the future precision measurements of $M_W$ and $Z$ decay parameters can determine the Higgs boson mass and distinguish the SM with radiative corrections from the minimal supersymmetric standard model (MSSM) and other extended model. |
2103.13401 | Michael Baker | Michael J. Baker, Peter Cox, Raymond R. Volkas | Radiative Muon Mass Models and $(g-2)_\mu$ | 14 pages, 5 figures; v2: references added, updated experimental g-2
measurement, matches published version | null | 10.1007/JHEP05(2021)174 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent measurements of the Higgs-muon coupling are directly probing muon mass
generation for the first time. We classify minimal models with a one-loop
radiative mass mechanism and show that benchmark models are consistent with
current experimental results. We find that these models are best probed by
measurements of $(g-2)_\mu$, even when taking into account the precision of
Higgs measurements expected at future colliders. The current $(g-2)_\mu$
anomaly, if confirmed, could therefore be a first hint that the muon mass has a
radiative origin.
| [
{
"created": "Wed, 24 Mar 2021 18:00:04 GMT",
"version": "v1"
},
{
"created": "Mon, 24 May 2021 00:39:35 GMT",
"version": "v2"
}
] | 2023-01-11 | [
[
"Baker",
"Michael J.",
""
],
[
"Cox",
"Peter",
""
],
[
"Volkas",
"Raymond R.",
""
]
] | Recent measurements of the Higgs-muon coupling are directly probing muon mass generation for the first time. We classify minimal models with a one-loop radiative mass mechanism and show that benchmark models are consistent with current experimental results. We find that these models are best probed by measurements of $(g-2)_\mu$, even when taking into account the precision of Higgs measurements expected at future colliders. The current $(g-2)_\mu$ anomaly, if confirmed, could therefore be a first hint that the muon mass has a radiative origin. |
0909.5086 | Johan Bijnens | Johan Bijnens and Lisa Carloni (Lund) | Leading Logarithms in the Massive O(N) Nonlinear Sigma Model | 22 pages | Nucl.Phys.B827:237-255,2010 | 10.1016/j.nuclphysb.2009.10.028 | LU TP 09-26 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review Buchler and Colangelo's result that leading divergences at any loop
order can be calculated using only one-loop calculations and we provide an
alternative proof. We then use this method to calculate the leading divergences
of and thus the leading logarithmic corrections to the meson mass in the
massive O(N) nonlinear sigma model to five-loop order. We also calculate the
all-loop result to leading order in the large $N$ expansion by showing that
only cactus diagrams contribute and by summing these via a generalized gap
equation.
| [
{
"created": "Mon, 28 Sep 2009 13:10:42 GMT",
"version": "v1"
}
] | 2010-01-08 | [
[
"Bijnens",
"Johan",
"",
"Lund"
],
[
"Carloni",
"Lisa",
"",
"Lund"
]
] | We review Buchler and Colangelo's result that leading divergences at any loop order can be calculated using only one-loop calculations and we provide an alternative proof. We then use this method to calculate the leading divergences of and thus the leading logarithmic corrections to the meson mass in the massive O(N) nonlinear sigma model to five-loop order. We also calculate the all-loop result to leading order in the large $N$ expansion by showing that only cactus diagrams contribute and by summing these via a generalized gap equation. |
1507.01018 | Don Colladay | Don Colladay and Patrick McDonald | Singular Lorentz-Violating Lagrangians and Associated Finsler Structures | 11 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Several lagrangians associated to classical limits of lorenz-violating
fermions in the Standard Model extension (SME) have been shown to yield Finsler
functions when the theory is expressed in Euclidean space. When spin-couplings
are present, the lagrangian can develop singularities that obstruct the
construction of a globally defined Legendre transformation, leading to singular
Finsler spaces. A specific sector of the SME where such problems arise is
studied. It is found that the singular behavior can be eliminated by an
appropriate lifting of the problem to an associated algebraic variety. This
provides a smooth classical model for the singular problem. In Euclidean space,
the procedure involves combining two related singular Finsler functions into a
single smooth function with a semi-positive definite quadratic form defined on
a desingularized variety.
| [
{
"created": "Fri, 3 Jul 2015 20:24:40 GMT",
"version": "v1"
}
] | 2015-07-07 | [
[
"Colladay",
"Don",
""
],
[
"McDonald",
"Patrick",
""
]
] | Several lagrangians associated to classical limits of lorenz-violating fermions in the Standard Model extension (SME) have been shown to yield Finsler functions when the theory is expressed in Euclidean space. When spin-couplings are present, the lagrangian can develop singularities that obstruct the construction of a globally defined Legendre transformation, leading to singular Finsler spaces. A specific sector of the SME where such problems arise is studied. It is found that the singular behavior can be eliminated by an appropriate lifting of the problem to an associated algebraic variety. This provides a smooth classical model for the singular problem. In Euclidean space, the procedure involves combining two related singular Finsler functions into a single smooth function with a semi-positive definite quadratic form defined on a desingularized variety. |
1408.1723 | Richard Keith Ellis | John M. Campbell, R. Keith Ellis and Ciaran Williams | Bounding the Higgs width at the LHC | 8 pages, 7 figures | null | null | FERMILAB-CONF-14-275-T | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present results for the Standard model description of the four-lepton
production, mediated both by Higgs boson production and by other one-loop
standard model processes. The description of four-lepton final states in MCFM
v6.8 is reviewed, with special reference to the interference effects that can
occur for identical species of leptons. We present results both for
interference in the $l^+l^- l^- l^+$ and in the $l^-l^+ \nu_l \bar{\nu}_l$
final state. Prospects for further improvement in the theoretical description
of four lepton production are also reviewed.
| [
{
"created": "Thu, 7 Aug 2014 22:04:04 GMT",
"version": "v1"
}
] | 2014-08-11 | [
[
"Campbell",
"John M.",
""
],
[
"Ellis",
"R. Keith",
""
],
[
"Williams",
"Ciaran",
""
]
] | We present results for the Standard model description of the four-lepton production, mediated both by Higgs boson production and by other one-loop standard model processes. The description of four-lepton final states in MCFM v6.8 is reviewed, with special reference to the interference effects that can occur for identical species of leptons. We present results both for interference in the $l^+l^- l^- l^+$ and in the $l^-l^+ \nu_l \bar{\nu}_l$ final state. Prospects for further improvement in the theoretical description of four lepton production are also reviewed. |
1308.3735 | Beranger Dumont | Genevieve Belanger, Guillaume Drieu La Rochelle, Beranger Dumont,
Rohini M. Godbole, Sabine Kraml, Suchita Kulkarni | LHC constraints on light neutralino dark matter in the MSSM | 18 pages, 6 figures; matches version accepted for publication in
Physics Letters B | Physics Letters B 726 (2013), pp. 773-780 | 10.1016/j.physletb.2013.09.059 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Light neutralino dark matter can be achieved in the Minimal Supersymmetric
Standard Model if staus are rather light, with mass around 100 GeV. We perform
a detailed analysis of the relevant supersymmetric parameter space, including
also the possibility of light selectons and smuons, and of light higgsino- or
wino-like charginos. In addition to the latest limits from direct and indirect
detection of dark matter, ATLAS and CMS constraints on electroweak-inos and on
sleptons are taken into account using a "simplified models" framework.
Measurements of the properties of the Higgs boson at 125 GeV, which constrain
amongst others the invisible decay of the Higgs boson into a pair of
neutralinos, are also implemented in the analysis. We show that viable
neutralino dark matter can be achieved for masses as low as 15 GeV. In this
case, light charginos close to the LEP bound are required in addition to light
right-chiral staus. Significant deviations are observed in the couplings of the
125 GeV Higgs boson. These constitute a promising way to probe the light
neutralino dark matter scenario in the next run of the LHC.
| [
{
"created": "Fri, 16 Aug 2013 23:00:14 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Sep 2013 08:47:00 GMT",
"version": "v2"
},
{
"created": "Wed, 2 Oct 2013 19:36:17 GMT",
"version": "v3"
}
] | 2013-11-07 | [
[
"Belanger",
"Genevieve",
""
],
[
"La Rochelle",
"Guillaume Drieu",
""
],
[
"Dumont",
"Beranger",
""
],
[
"Godbole",
"Rohini M.",
""
],
[
"Kraml",
"Sabine",
""
],
[
"Kulkarni",
"Suchita",
""
]
] | Light neutralino dark matter can be achieved in the Minimal Supersymmetric Standard Model if staus are rather light, with mass around 100 GeV. We perform a detailed analysis of the relevant supersymmetric parameter space, including also the possibility of light selectons and smuons, and of light higgsino- or wino-like charginos. In addition to the latest limits from direct and indirect detection of dark matter, ATLAS and CMS constraints on electroweak-inos and on sleptons are taken into account using a "simplified models" framework. Measurements of the properties of the Higgs boson at 125 GeV, which constrain amongst others the invisible decay of the Higgs boson into a pair of neutralinos, are also implemented in the analysis. We show that viable neutralino dark matter can be achieved for masses as low as 15 GeV. In this case, light charginos close to the LEP bound are required in addition to light right-chiral staus. Significant deviations are observed in the couplings of the 125 GeV Higgs boson. These constitute a promising way to probe the light neutralino dark matter scenario in the next run of the LHC. |
hep-ph/0110079 | Zhang Ailin | Zhi-yong Wang and Ailin Zhang | New interpretation to zitterbewegung | 5 pages, no figures, revtex | null | null | null | hep-ph | null | In previous investigations on zitterbewegung(zbw) of electron, it is believed
that the zbw results from some internal motion of electron. However, all the
analyses are made at relativistic quantum mechanical level. In framework of
quantum field theory (QFT), we find that the origin of zbw is different from
previous conclusion. Especially, some new interesting conclusions are derived
at this level: 1) the zbw arises from the rapid to-and-fro polarization of the
vacuum in the range of the Compton wavelength (divided by $4\pi$) of the
electron, which offer the four-dimensional(4D) spin and intrinsic
electromagnetic-moment tensor to the electron; 2) Any attempt that attributes
spin (rather than double the spin) of the electron to some kind of orbital
angular momentum would not be successful; 3) the macroscopic classical speed of
the Dirac vacuum medium vanish in all inertial systems.
| [
{
"created": "Fri, 5 Oct 2001 03:01:30 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Wang",
"Zhi-yong",
""
],
[
"Zhang",
"Ailin",
""
]
] | In previous investigations on zitterbewegung(zbw) of electron, it is believed that the zbw results from some internal motion of electron. However, all the analyses are made at relativistic quantum mechanical level. In framework of quantum field theory (QFT), we find that the origin of zbw is different from previous conclusion. Especially, some new interesting conclusions are derived at this level: 1) the zbw arises from the rapid to-and-fro polarization of the vacuum in the range of the Compton wavelength (divided by $4\pi$) of the electron, which offer the four-dimensional(4D) spin and intrinsic electromagnetic-moment tensor to the electron; 2) Any attempt that attributes spin (rather than double the spin) of the electron to some kind of orbital angular momentum would not be successful; 3) the macroscopic classical speed of the Dirac vacuum medium vanish in all inertial systems. |
1210.3019 | Azar Mustafayev | Howard Baer, Vernon Barger, Peisi Huang, Dan Mickelson, Azar
Mustafayev and Xerxes Tata | Post-LHC7 fine-tuning in the mSUGRA/CMSSM model with a 125 GeV Higgs
boson | 22 pages, 11 figures; added references and LHCb constraint. version
to appear in PRD | null | 10.1103/PhysRevD.87.035017 | UH-511-1202-12 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recent discovery of a 125 GeV Higgs-like resonance at LHC, coupled with
the lack of evidence for weak scale supersymmetry (SUSY), have severely
constrained SUSY models such as mSUGRA/CMSSM. As LHC probes deeper into SUSY
model parameter space, the little hierarchy problem -- how to reconcile the Z
and Higgs boson mass scale with the scale of SUSY breaking -- will become
increasingly exacerbated unless a sparticle signal is found. We evaluate two
different measures of fine-tuning in the mSUGRA/CMSSM model. The more stringent
of these, \Delta_{HS}, includes effects that arise from the high scale origin
of the mSUGRA parameters while the second measure, \Delta_{EW}, is determined
only by weak scale parameters: hence, it is universal to any model with the
same particle spectrum and couplings. Our results incorporate the latest
constraints from LHC7 sparticle searches, LHCb limits from B_s ->\mu^+\mu^- and
also require a light Higgs scalar with m_h ~123-127 GeV. We present fine-tuning
contours in the m_0 vs. m_{1/2} plane for several sets of A_0 and tan(\beta)
values. We also present results for \Delta_{HS} and \Delta_{EW} from a scan
over the entire viable model parameter space. We find a \Delta_{HS} > 10^3, or
at best 0.1% fine-tuning. For the less stringent electroweak fine tuning, we
find \Delta_{EW} > 10^2, or at best 1% fine-tuning. Two benchmark points are
presented that have the lowest values of \Delta_{HS} and \Delta_{EW}. Our
results provide a quantitative measure for ascertaining whether or not the
remaining mSUGRA/CMSSM model parameter space is excessively fine-tuned, and so
could provide impetus for considering alternative SUSY models.
| [
{
"created": "Wed, 10 Oct 2012 19:59:25 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Jan 2013 20:36:57 GMT",
"version": "v2"
}
] | 2015-06-11 | [
[
"Baer",
"Howard",
""
],
[
"Barger",
"Vernon",
""
],
[
"Huang",
"Peisi",
""
],
[
"Mickelson",
"Dan",
""
],
[
"Mustafayev",
"Azar",
""
],
[
"Tata",
"Xerxes",
""
]
] | The recent discovery of a 125 GeV Higgs-like resonance at LHC, coupled with the lack of evidence for weak scale supersymmetry (SUSY), have severely constrained SUSY models such as mSUGRA/CMSSM. As LHC probes deeper into SUSY model parameter space, the little hierarchy problem -- how to reconcile the Z and Higgs boson mass scale with the scale of SUSY breaking -- will become increasingly exacerbated unless a sparticle signal is found. We evaluate two different measures of fine-tuning in the mSUGRA/CMSSM model. The more stringent of these, \Delta_{HS}, includes effects that arise from the high scale origin of the mSUGRA parameters while the second measure, \Delta_{EW}, is determined only by weak scale parameters: hence, it is universal to any model with the same particle spectrum and couplings. Our results incorporate the latest constraints from LHC7 sparticle searches, LHCb limits from B_s ->\mu^+\mu^- and also require a light Higgs scalar with m_h ~123-127 GeV. We present fine-tuning contours in the m_0 vs. m_{1/2} plane for several sets of A_0 and tan(\beta) values. We also present results for \Delta_{HS} and \Delta_{EW} from a scan over the entire viable model parameter space. We find a \Delta_{HS} > 10^3, or at best 0.1% fine-tuning. For the less stringent electroweak fine tuning, we find \Delta_{EW} > 10^2, or at best 1% fine-tuning. Two benchmark points are presented that have the lowest values of \Delta_{HS} and \Delta_{EW}. Our results provide a quantitative measure for ascertaining whether or not the remaining mSUGRA/CMSSM model parameter space is excessively fine-tuned, and so could provide impetus for considering alternative SUSY models. |
1409.4283 | Christopher Deans | Christopher S. Deans | Closure testing the NNPDF3.0 methodology | 4 pages, 4 figures, to appear in the proceedings of the 17th
High-Energy Physics International Conference in Quantum Chromodynamics
(QCD14), Montpellier, 30 June - 4 July, 2014 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A thorough understanding of the issues surrounding the determination of
parton distributions is crucial due to their importance to calculations of LHC
observables. However, it is still not fully understood how much of an impact
methodological bias has on PDF fits. Closure tests, where a fit is performed to
pseudo-data generated using an existing PDF set, provide a way of directly
investigating whether current PDF fitting methodologies are successful. Here,
we present a sample of results from closure tests applying the NNPDF
methodology to data created using a variety of different PDF sets. The results
validate our methodology by showing that the initial PDFs can be reproduced
within uncertainties. We also briefly discuss our latest PDF determination,
NNPDF3.0, which has been developed making extensive use of the closure test
technique.
| [
{
"created": "Mon, 15 Sep 2014 14:55:33 GMT",
"version": "v1"
}
] | 2014-09-16 | [
[
"Deans",
"Christopher S.",
""
]
] | A thorough understanding of the issues surrounding the determination of parton distributions is crucial due to their importance to calculations of LHC observables. However, it is still not fully understood how much of an impact methodological bias has on PDF fits. Closure tests, where a fit is performed to pseudo-data generated using an existing PDF set, provide a way of directly investigating whether current PDF fitting methodologies are successful. Here, we present a sample of results from closure tests applying the NNPDF methodology to data created using a variety of different PDF sets. The results validate our methodology by showing that the initial PDFs can be reproduced within uncertainties. We also briefly discuss our latest PDF determination, NNPDF3.0, which has been developed making extensive use of the closure test technique. |
hep-ph/9607388 | Tadashi Kon | Alfred Bartl (Vienna U.), Helmut Eberl (Vienna, OAW), Keisho Hidaka
(Tokyo-Gakugei U.), Tadashi Kon (Seikei U.), Walter Majerotto (Vienna, OAW)
and Yoichi Yamada (U. Wisconsin) | Impact of squark pair decay modes on search for supersymmetric neutral
Higgs bosons | 15 pages, LaTeX, also available at
ftp://physics.ge.seikei.ac.jp/Pub/preprint/itpsu9603.uu (uuencoded
postscript) | Phys.Lett. B389 (1996) 538-544 | 10.1016/S0370-2693(96)01312-3 | UWThPh-1996-44, HEPHY-PUB 650/96, TGU-18, ITP-SU-96/03, MADPH-96-952 | hep-ph | null | We present a detailed study of the decays of the neutral Higgs bosons $H^0$
and $A^0$ within the Minimal Supersymmetric Standard Model. We find that the
supersymmetric modes ${\tilde{t}}\bar{\tilde{t}}$ and
${\tilde{b}}\bar{\tilde{b}}$ can dominate the $H^0$ and $A^0$ decays in a wide
range of the model parameters due to large Yukawa couplings and mixings of
${\tilde{t}}$ and ${\tilde{b}}$. Compared to the conventional modes $t\bar{t}$
and $b\bar{b}$, these modes have very distinctive signatures. This could have a
decisive impact on the neutral Higgs boson searches at future colliders.
| [
{
"created": "Tue, 23 Jul 1996 04:14:01 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Bartl",
"Alfred",
"",
"Vienna U."
],
[
"Eberl",
"Helmut",
"",
"Vienna, OAW"
],
[
"Hidaka",
"Keisho",
"",
"Tokyo-Gakugei U."
],
[
"Kon",
"Tadashi",
"",
"Seikei U."
],
[
"Majerotto",
"Walter",
"",
"Vienna, OAW"
],
[
"Yamada",
"Yoichi",
"",
"U. Wisconsin"
]
] | We present a detailed study of the decays of the neutral Higgs bosons $H^0$ and $A^0$ within the Minimal Supersymmetric Standard Model. We find that the supersymmetric modes ${\tilde{t}}\bar{\tilde{t}}$ and ${\tilde{b}}\bar{\tilde{b}}$ can dominate the $H^0$ and $A^0$ decays in a wide range of the model parameters due to large Yukawa couplings and mixings of ${\tilde{t}}$ and ${\tilde{b}}$. Compared to the conventional modes $t\bar{t}$ and $b\bar{b}$, these modes have very distinctive signatures. This could have a decisive impact on the neutral Higgs boson searches at future colliders. |
hep-ph/9703357 | Vladimir Smirnov | V.A. Smirnov | Asymptotic expansions of two-loop Feynman diagrams in the Sudakov limit | 9 pages, LaTeX with axodraw.sty | Phys.Lett. B404 (1997) 101-107 | 10.1016/S0370-2693(97)00545-5 | null | hep-ph hep-th | null | Recently presented explicit formulae for asymptotic expansions of Feynman
diagrams in the Sudakov limit are applied to typical two-loop diagrams. For a
diagram with one non-zero mass these formulae provide an algorithm for
analytical calculation of all powers and logarithms, i.e. coefficients in the
corresponding expansion $(Q^2)^{-2} \sum_{n,j=0} c_{nj} t^{-n} \ln^j t$, with
$t=Q^2/m^2$ and $j \leq 4$. Results for the coefficients at several first
powers are presented. For a diagram with two non-zero masses, results for all
the logarithms and the leading power, i.e. the coefficients $c_{nj}$ for n=0
and j=4,3,2,1,0 are obtained. A typical feature of these explicit formulae
(written through a sum over a specific family of subgraphs of a given graph,
similar to asymptotic expansions for off-shell limits of momenta and masses) is
an interplay between ultraviolet, collinear and infrared divergences which
represent themselves as poles in the parameter $\eps=(4-d)/2$ of dimensional
regularization. In particular, in the case of the second diagram, which is free
from the divergences, individual terms of the asymptotic expansion involve all
the three kinds of divergences resulting in poles, up to $1/\eps^4$, which are
successfully canceled in the sum.
| [
{
"created": "Tue, 18 Mar 1997 15:11:58 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Smirnov",
"V. A.",
""
]
] | Recently presented explicit formulae for asymptotic expansions of Feynman diagrams in the Sudakov limit are applied to typical two-loop diagrams. For a diagram with one non-zero mass these formulae provide an algorithm for analytical calculation of all powers and logarithms, i.e. coefficients in the corresponding expansion $(Q^2)^{-2} \sum_{n,j=0} c_{nj} t^{-n} \ln^j t$, with $t=Q^2/m^2$ and $j \leq 4$. Results for the coefficients at several first powers are presented. For a diagram with two non-zero masses, results for all the logarithms and the leading power, i.e. the coefficients $c_{nj}$ for n=0 and j=4,3,2,1,0 are obtained. A typical feature of these explicit formulae (written through a sum over a specific family of subgraphs of a given graph, similar to asymptotic expansions for off-shell limits of momenta and masses) is an interplay between ultraviolet, collinear and infrared divergences which represent themselves as poles in the parameter $\eps=(4-d)/2$ of dimensional regularization. In particular, in the case of the second diagram, which is free from the divergences, individual terms of the asymptotic expansion involve all the three kinds of divergences resulting in poles, up to $1/\eps^4$, which are successfully canceled in the sum. |
1506.03970 | Roman Zwicky | James Gratrex, Markus Hopfer, and Roman Zwicky | Generalised helicity formalism, higher moments and the $B \to
K_{J_K}(\to K \pi) \bar{\ell}_1 \ell_2$ angular distributions | identical to version appeared in PRD. typo in Eq below C.9 corrected,
includes Mathematica notebook with angular distribution same as v2 | Phys. Rev. D 93, 054008 (2016) | 10.1103/PhysRevD.93.054008 | CP3-Origins-2015-017 DNRF90, DIAS-2015-17 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We generalise the Jacob-Wick helicity formalism, which applies to sequential
decays, to effective field theories of rare decays of the type $B \to
K_{J_K}(\to K \pi) \bar{\ell}_1 \ell_2$. This is achieved by reinterpreting
local interaction vertices $\bar b \Gamma'_{\mu_1 ..\mu_n} s \bar \ell
\Gamma^{\mu_1 ..\mu_n} \ell$ as a coherent sum of $1 \to 2$ processes mediated
by particles whose spin ranges between zero and $n$. We illustrate the
framework by deriving the full angular distributions for $B \to K\bar{\ell}_1
\ell_2$ and $B \to K^*(\to K \pi) \bar{\ell}_1 \ell_2$ for the complete
dimension-six effective Hamiltonian for non-equal lepton masses. Amplitudes and
decay rates are expressed in terms of Wigner rotation matrices, leading
naturally to the method of moments in various forms. We discuss how higher-spin
operators and QED corrections alter the standard angular distribution used
throughout the literature, potentially leading to differences between the
method of moments and the likelihood fits. We propose to diagnose these effects
by assessing higher angular moments. These could be relevant in investigating
the nature of the current LHCb anomalies in $R_K = {\cal B}( B \to K
\mu^+\mu^-) /{\cal B}( B \to K e^+e^-)$ as well as angular observables in $B
\to K^* \mu^+\mu^-$.
| [
{
"created": "Fri, 12 Jun 2015 10:27:32 GMT",
"version": "v1"
},
{
"created": "Sat, 10 Oct 2015 19:26:44 GMT",
"version": "v2"
},
{
"created": "Fri, 11 Mar 2016 00:26:41 GMT",
"version": "v3"
}
] | 2021-07-05 | [
[
"Gratrex",
"James",
""
],
[
"Hopfer",
"Markus",
""
],
[
"Zwicky",
"Roman",
""
]
] | We generalise the Jacob-Wick helicity formalism, which applies to sequential decays, to effective field theories of rare decays of the type $B \to K_{J_K}(\to K \pi) \bar{\ell}_1 \ell_2$. This is achieved by reinterpreting local interaction vertices $\bar b \Gamma'_{\mu_1 ..\mu_n} s \bar \ell \Gamma^{\mu_1 ..\mu_n} \ell$ as a coherent sum of $1 \to 2$ processes mediated by particles whose spin ranges between zero and $n$. We illustrate the framework by deriving the full angular distributions for $B \to K\bar{\ell}_1 \ell_2$ and $B \to K^*(\to K \pi) \bar{\ell}_1 \ell_2$ for the complete dimension-six effective Hamiltonian for non-equal lepton masses. Amplitudes and decay rates are expressed in terms of Wigner rotation matrices, leading naturally to the method of moments in various forms. We discuss how higher-spin operators and QED corrections alter the standard angular distribution used throughout the literature, potentially leading to differences between the method of moments and the likelihood fits. We propose to diagnose these effects by assessing higher angular moments. These could be relevant in investigating the nature of the current LHCb anomalies in $R_K = {\cal B}( B \to K \mu^+\mu^-) /{\cal B}( B \to K e^+e^-)$ as well as angular observables in $B \to K^* \mu^+\mu^-$. |
hep-ph/9609367 | William Kilgore | William B. Kilgore (Fermilab) | Gluonic Three Jet Production at Next to Leading Order | 4 pages, 2 figures, LaTeX, uses sprocl.sty and epsf.sty | null | null | Fermilab-Conf-96/315-T | hep-ph | null | I report results from a next-to-leading order event generator of purely
gluonic jet production. This calculation, is the first step in the construction
of a full next-to-leading order calculation of three jet production at hadron
colliders.
| [
{
"created": "Mon, 16 Sep 1996 15:03:57 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kilgore",
"William B.",
"",
"Fermilab"
]
] | I report results from a next-to-leading order event generator of purely gluonic jet production. This calculation, is the first step in the construction of a full next-to-leading order calculation of three jet production at hadron colliders. |
hep-ph/0412327 | Kim Maltman | K. Maltman | Heavy Antiquark Pentaquarks in the CM and GB Models | 4 pages. Prepared for the Proceedings of MENU'04, Beijing, Aug.
29-Sept. 04, 2004 | Int.J.Mod.Phys. A20 (2005) 1977-1980 | 10.1142/S0217751X05023773 | null | hep-ph | null | The splittings between positive parity pentaquarks containing a single heavy
(c,b) antiquark and four light (u,d) quarks are investigated in models having
spin-dependent interactions generated by either effective Goldstone boson
exchange or effective color magnetic exchange. Model-independent features of
these splittings are emphasized. Overlaps to the ``fall-apart'' decay
configurations ND, ND* or NB, NB*, relevant to decay couplings for the various
2-body pentaquark decays, are also computed.
| [
{
"created": "Wed, 22 Dec 2004 03:44:53 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Maltman",
"K.",
""
]
] | The splittings between positive parity pentaquarks containing a single heavy (c,b) antiquark and four light (u,d) quarks are investigated in models having spin-dependent interactions generated by either effective Goldstone boson exchange or effective color magnetic exchange. Model-independent features of these splittings are emphasized. Overlaps to the ``fall-apart'' decay configurations ND, ND* or NB, NB*, relevant to decay couplings for the various 2-body pentaquark decays, are also computed. |
hep-ph/9712393 | Avto Kharchilava | I. Iashvili and A. Kharchilava (Institute of Physics, Georgian Academy
of Sciences, Tbilisi) | Search for the next-to-lightest neutralino | LaTeX, 10 pages, 7 eps figures; submitted to Nuclear Physics B; a
more detailed version is available under
ftp://cmsdoc.cern.ch/documents/97/note97_065.ps.Z | Nucl.Phys. B526 (1998) 153-162 | 10.1016/S0550-3213(98)00417-9 | null | hep-ph hep-ex | null | We study the inclusive production of the next-to-lightest neutralino chi2,
decaying directly, or via slepton, into two leptons and the lightest
neutralino. The dilepton invariant mass spectrum in these decays has a
characteristic sharp edge near the kinematical upper limit. We propose to
exploit this feature as a search strategy for the chi2, and thereby for SUSY.
The possibilities to determine neutralinos and slepton masses are also
discussed.
| [
{
"created": "Tue, 16 Dec 1997 09:20:19 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Iashvili",
"I.",
"",
"Institute of Physics, Georgian Academy\n of Sciences, Tbilisi"
],
[
"Kharchilava",
"A.",
"",
"Institute of Physics, Georgian Academy\n of Sciences, Tbilisi"
]
] | We study the inclusive production of the next-to-lightest neutralino chi2, decaying directly, or via slepton, into two leptons and the lightest neutralino. The dilepton invariant mass spectrum in these decays has a characteristic sharp edge near the kinematical upper limit. We propose to exploit this feature as a search strategy for the chi2, and thereby for SUSY. The possibilities to determine neutralinos and slepton masses are also discussed. |
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