id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1507.08673 | Daniel Schmeier | Jong Soo Kim, Oleg Lebedev and Daniel Schmeier | Higgsophilic gauge bosons and monojets at the LHC | 18 pages, 4 figures | null | 10.1007/JHEP11(2015)128 | IFT-UAM/CSIC-15-078 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a generic framework where the Standard Model (SM) coexists with a
hidden sector endowed with some additional gauge symmetry. When this symmetry
is broken by a scalar field charged under the hidden gauge group, the
corresponding scalar boson generally mixes with the SM Higgs boson. In
addition, massive hidden gauge bosons emerge and via the mixing, the observed
Higgs-like mass eigenstate is the only known particle that couples to these
hidden gauge bosons directly.
We study the LHC monojet signatures of this scenario and the corresponding
constraints on the gauge coupling of the hidden gauge group as well as the
mixing of the Higgs scalars.
| [
{
"created": "Thu, 30 Jul 2015 20:15:24 GMT",
"version": "v1"
}
] | 2016-01-20 | [
[
"Kim",
"Jong Soo",
""
],
[
"Lebedev",
"Oleg",
""
],
[
"Schmeier",
"Daniel",
""
]
] | We consider a generic framework where the Standard Model (SM) coexists with a hidden sector endowed with some additional gauge symmetry. When this symmetry is broken by a scalar field charged under the hidden gauge group, the corresponding scalar boson generally mixes with the SM Higgs boson. In addition, massive hidden gauge bosons emerge and via the mixing, the observed Higgs-like mass eigenstate is the only known particle that couples to these hidden gauge bosons directly. We study the LHC monojet signatures of this scenario and the corresponding constraints on the gauge coupling of the hidden gauge group as well as the mixing of the Higgs scalars. |
1706.08437 | Rusa Mandal | Debajyoti Choudhury, Anirban Kundu, Rusa Mandal and Rahul Sinha | Minimal unified resolution to $R_{K^{(*)}}$ and $R(D^{(*)})$ anomalies
with lepton mixing | Matches with the published version | Phys. Rev. Lett. 119, 151801 (2017) | 10.1103/PhysRevLett.119.151801 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is a challenging task to explain, in terms of a simple and compelling new
physics scenario, the intriguing discrepancies between the standard model
expectations and the data for the neutral-current observables $R_K$ and
$R_{K^*}$, as well as the charged-current observables $R(D)$ and $R(D^*)$. We
show that this can be achieved in an effective theory with only two unknown
parameters. In addition, this class of models predicts some interesting
signatures in the context of both $B$ decays as well as high-energy collisions.
| [
{
"created": "Mon, 26 Jun 2017 15:24:31 GMT",
"version": "v1"
},
{
"created": "Sat, 9 Sep 2017 20:43:55 GMT",
"version": "v2"
},
{
"created": "Mon, 16 Oct 2017 10:45:40 GMT",
"version": "v3"
}
] | 2017-10-18 | [
[
"Choudhury",
"Debajyoti",
""
],
[
"Kundu",
"Anirban",
""
],
[
"Mandal",
"Rusa",
""
],
[
"Sinha",
"Rahul",
""
]
] | It is a challenging task to explain, in terms of a simple and compelling new physics scenario, the intriguing discrepancies between the standard model expectations and the data for the neutral-current observables $R_K$ and $R_{K^*}$, as well as the charged-current observables $R(D)$ and $R(D^*)$. We show that this can be achieved in an effective theory with only two unknown parameters. In addition, this class of models predicts some interesting signatures in the context of both $B$ decays as well as high-energy collisions. |
hep-ph/9305344 | null | N.K. Mondal and D.P. Roy | An Effective $p_T$ Cutoff for the Isolalated Lepton Background from
Bottom Decay -- | TIFR/TH/93-23 (LATEX, 20 pages, 7 figures available on request) | Phys.Rev.D49:183-189,1994 | 10.1103/PhysRevD.49.183 | null | hep-ph | null | There is a strong correlation between the $p_T$ and isolation of the lepton
coming from $B$ decay. Consequently the isolated lepton background from $B$
decay goes down rapidly with increasing lepton $p_T$; and there is a $p_T$
cutoff beyond which it effectively vanishes. For the isolation cut of $E^{AC}_T
< 10$ GeV, appropriate for LHC, the lepton $p_T$ cutoff is 80 GeV. This can be
exploited to effectively eliminate the $B$ background from the like sign
dilepton channel apropriate for Majorana particle searches, as well as the
unlike sign dilepton and the single lepton channels appropriate for the top
quark search. We illustrate this with a detailed analysis of the $B$ background
in these channels along with the signals at LHC energy using both parton level
MC and ISAJET programs.
| [
{
"created": "Fri, 28 May 1993 09:38:00 GMT",
"version": "v1"
}
] | 2011-01-13 | [
[
"Mondal",
"N. K.",
""
],
[
"Roy",
"D. P.",
""
]
] | There is a strong correlation between the $p_T$ and isolation of the lepton coming from $B$ decay. Consequently the isolated lepton background from $B$ decay goes down rapidly with increasing lepton $p_T$; and there is a $p_T$ cutoff beyond which it effectively vanishes. For the isolation cut of $E^{AC}_T < 10$ GeV, appropriate for LHC, the lepton $p_T$ cutoff is 80 GeV. This can be exploited to effectively eliminate the $B$ background from the like sign dilepton channel apropriate for Majorana particle searches, as well as the unlike sign dilepton and the single lepton channels appropriate for the top quark search. We illustrate this with a detailed analysis of the $B$ background in these channels along with the signals at LHC energy using both parton level MC and ISAJET programs. |
1004.2037 | Philip Tanedo | Csaba Cs\'aki, Yuval Grossman, Philip Tanedo, Yuhsin Tsai | Warped Penguins | 29 pages + appendices (55 pages total). 11 figures. Corrected typos,
updated references. Corrected diagrams, main conclusions unchanged | Phys.Rev.D83:073002,2011 | 10.1103/PhysRevD.83.073002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an analysis of the loop-induced magnetic dipole operator in the
Randall-Sundrum model of a warped extra dimension with anarchic bulk fermions
and an IR brane localized Higgs. These operators are finite at one-loop order
and we explicitly calculate the branching ratio for mu to e gamma using the
mixed position/momentum space formalism. The particular bound on the anarchic
Yukawa and KK scales can depend on the flavor structure of the anarchic
matrices. It is possible for a generic model to either be ruled out or
unaffected by these bounds without any fine tuning. We quantify how these
models realize this surprising behavior. We also review tree-level lepton
flavor bounds in these models and show that these are are in mild tension with
the penguin bounds from typical models with a 3 TeV Kaluza-Klein scale.
Further, we illuminate the nature of the one-loop finiteness of these diagrams
and show how to accurately determine the degree of divergence of a 5D loop
diagram using both the 5D and KK formalism. This power counting can be
obfuscated in the 4D Kaluza-Klein formalism and we explicitly point out
subtleties that ensure that the two formalisms agree. Finally, we remark on the
existence of a perturbative regime in which these one-loop results give the
dominant contribution.
| [
{
"created": "Mon, 12 Apr 2010 20:00:00 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Jan 2011 20:34:08 GMT",
"version": "v2"
},
{
"created": "Thu, 5 Jan 2012 22:02:35 GMT",
"version": "v3"
},
{
"created": "Wed, 18 Apr 2012 04:23:01 GMT",
"version": "v4"
}
] | 2015-03-14 | [
[
"Csáki",
"Csaba",
""
],
[
"Grossman",
"Yuval",
""
],
[
"Tanedo",
"Philip",
""
],
[
"Tsai",
"Yuhsin",
""
]
] | We present an analysis of the loop-induced magnetic dipole operator in the Randall-Sundrum model of a warped extra dimension with anarchic bulk fermions and an IR brane localized Higgs. These operators are finite at one-loop order and we explicitly calculate the branching ratio for mu to e gamma using the mixed position/momentum space formalism. The particular bound on the anarchic Yukawa and KK scales can depend on the flavor structure of the anarchic matrices. It is possible for a generic model to either be ruled out or unaffected by these bounds without any fine tuning. We quantify how these models realize this surprising behavior. We also review tree-level lepton flavor bounds in these models and show that these are are in mild tension with the penguin bounds from typical models with a 3 TeV Kaluza-Klein scale. Further, we illuminate the nature of the one-loop finiteness of these diagrams and show how to accurately determine the degree of divergence of a 5D loop diagram using both the 5D and KK formalism. This power counting can be obfuscated in the 4D Kaluza-Klein formalism and we explicitly point out subtleties that ensure that the two formalisms agree. Finally, we remark on the existence of a perturbative regime in which these one-loop results give the dominant contribution. |
0809.3453 | Eduardo Pont\'on | Puneet Batra and Eduardo Ponton | The Supersymmetric Higgs | 34 pages, 5 figures | Phys.Rev.D79:035001,2009 | 10.1103/PhysRevD.79.035001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the Minimal Supersymmetric Standard Model (the MSSM), the electroweak
symmetry is restored as supersymmetry-breaking terms are turned off. We
describe a generic extension of the MSSM where the electroweak symmetry is
broken in the supersymmetric limit. We call this limit the "sEWSB" phase, short
for supersymmetric electroweak symmetry breaking. We define this phase in an
effective field theory that only contains the MSSM degrees of freedom. The
sEWSB vacua naturally have an inverted scalar spectrum, where the heaviest
CP-even Higgs state has Standard Model-like couplings to the massive vector
bosons; experimental constraints in the scalar Higgs sector are more easily
satisfied than in the MSSM.
| [
{
"created": "Mon, 22 Sep 2008 11:07:54 GMT",
"version": "v1"
}
] | 2009-02-20 | [
[
"Batra",
"Puneet",
""
],
[
"Ponton",
"Eduardo",
""
]
] | In the Minimal Supersymmetric Standard Model (the MSSM), the electroweak symmetry is restored as supersymmetry-breaking terms are turned off. We describe a generic extension of the MSSM where the electroweak symmetry is broken in the supersymmetric limit. We call this limit the "sEWSB" phase, short for supersymmetric electroweak symmetry breaking. We define this phase in an effective field theory that only contains the MSSM degrees of freedom. The sEWSB vacua naturally have an inverted scalar spectrum, where the heaviest CP-even Higgs state has Standard Model-like couplings to the massive vector bosons; experimental constraints in the scalar Higgs sector are more easily satisfied than in the MSSM. |
hep-ph/0408340 | Sven Heinemeyer | S. Heinemeyer | MSSM Higgs Physics: Theoretical Developments | 5 pages, 1 figure. Talk given at the LCWS Paris, France, April 2004 | null | null | CERN-PH-TH/2004-158 | hep-ph | null | The corrections to the MSSM Higgs boson masses and couplings performed in
this millennium are briefly reviewed. For the lightest MSSM Higgs boson mass,
m_h, we list the current status of the intrinsic uncertainties (due to unknown
higher-order corrections) and the parametric uncertainties (due to the
imperfect experimental knowledge of the input parameters). The need for
high-precision calculations in the MSSM Higgs boson sector is exemplified in a
realistic example.
| [
{
"created": "Mon, 30 Aug 2004 20:03:16 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Heinemeyer",
"S.",
""
]
] | The corrections to the MSSM Higgs boson masses and couplings performed in this millennium are briefly reviewed. For the lightest MSSM Higgs boson mass, m_h, we list the current status of the intrinsic uncertainties (due to unknown higher-order corrections) and the parametric uncertainties (due to the imperfect experimental knowledge of the input parameters). The need for high-precision calculations in the MSSM Higgs boson sector is exemplified in a realistic example. |
hep-ph/0209341 | Alex Krasnitz | Alex Krasnitz, Yasushi Nara, Raju Venugopalan | Elliptic Flow from Color Glass Condensate | 4 pages, 2 figures, talk contributed to Quark Matter-2002 conference
(Nantes, France, July 2002) | Nucl.Phys.A715:669-672,2003 | 10.1016/S0375-9474(02)01463-X | null | hep-ph | null | We show that an observable fraction of the measured elliptic flow may
originate in classical gluon fields at the initial stage of a peripheral
high-energy nuclear collision. This mechanism complements the contribution of
late stage mechanisms, such as those described by hydrodynamics, to the
observed elliptic flow.
| [
{
"created": "Fri, 27 Sep 2002 22:58:42 GMT",
"version": "v1"
}
] | 2010-11-30 | [
[
"Krasnitz",
"Alex",
""
],
[
"Nara",
"Yasushi",
""
],
[
"Venugopalan",
"Raju",
""
]
] | We show that an observable fraction of the measured elliptic flow may originate in classical gluon fields at the initial stage of a peripheral high-energy nuclear collision. This mechanism complements the contribution of late stage mechanisms, such as those described by hydrodynamics, to the observed elliptic flow. |
1506.01386 | Peter Stoffer | Gilberto Colangelo, Martin Hoferichter, Massimiliano Procura, Peter
Stoffer | Dispersion relation for hadronic light-by-light scattering: theoretical
foundations | 59 pages, 11 figures. Draws on and substantially extends
arXiv:1412.5171 [hep-ph] and arXiv:1402.7081 [hep-ph]. Version accepted for
publication in JHEP | null | 10.1007/JHEP09(2015)074 | INT-PUB-15-019, UWTHPH-2015-10 | hep-ph hep-ex hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we make a further step towards a dispersive description of the
hadronic light-by-light (HLbL) tensor, which should ultimately lead to a
data-driven evaluation of its contribution to $(g-2)_\mu$. We first provide a
Lorentz decomposition of the HLbL tensor performed according to the general
recipe by Bardeen, Tung, and Tarrach, generalizing and extending our previous
approach, which was constructed in terms of a basis of helicity amplitudes.
Such a tensor decomposition has several advantages: the role of gauge
invariance and crossing symmetry becomes fully transparent; the scalar
coefficient functions are free of kinematic singularities and zeros, and thus
fulfill a Mandelstam double-dispersive representation; and the explicit
relation for the HLbL contribution to $(g-2)_\mu$ in terms of the coefficient
functions simplifies substantially. We demonstrate explicitly that the
dispersive approach defines both the pion-pole and the pion-loop contribution
unambiguously and in a model-independent way. The pion loop, dispersively
defined as pion-box topology, is proven to coincide exactly with the one-loop
scalar QED amplitude, multiplied by the appropriate pion vector form factors.
| [
{
"created": "Wed, 3 Jun 2015 20:01:44 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Sep 2015 08:21:47 GMT",
"version": "v2"
}
] | 2015-09-23 | [
[
"Colangelo",
"Gilberto",
""
],
[
"Hoferichter",
"Martin",
""
],
[
"Procura",
"Massimiliano",
""
],
[
"Stoffer",
"Peter",
""
]
] | In this paper we make a further step towards a dispersive description of the hadronic light-by-light (HLbL) tensor, which should ultimately lead to a data-driven evaluation of its contribution to $(g-2)_\mu$. We first provide a Lorentz decomposition of the HLbL tensor performed according to the general recipe by Bardeen, Tung, and Tarrach, generalizing and extending our previous approach, which was constructed in terms of a basis of helicity amplitudes. Such a tensor decomposition has several advantages: the role of gauge invariance and crossing symmetry becomes fully transparent; the scalar coefficient functions are free of kinematic singularities and zeros, and thus fulfill a Mandelstam double-dispersive representation; and the explicit relation for the HLbL contribution to $(g-2)_\mu$ in terms of the coefficient functions simplifies substantially. We demonstrate explicitly that the dispersive approach defines both the pion-pole and the pion-loop contribution unambiguously and in a model-independent way. The pion loop, dispersively defined as pion-box topology, is proven to coincide exactly with the one-loop scalar QED amplitude, multiplied by the appropriate pion vector form factors. |
1805.08198 | Luis Hernandez | Alejandro Ayala, C. A. Dominguez, Saul Hernandez-Ortiz, L. A.
Hernandez, M. Loewe, D. Manreza Paret and R. Zamora | Thermo-magnetic evolution of the QCD strong coupling | 5 pages, 1 figure, typo in eq.(13) fixed, conclusions unchanged | Phys. Rev. D 98, 031501 (2018) | 10.1103/PhysRevD.98.031501 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the one-loop gluon polarization tensor at zero and finite
temperature in the presence of a magnetic field, to extract the thermo-magnetic
evolution of the strong coupling $\alpha_s$. We analyze four distinct regimes,
to wit, the small and large field cases, both at zero and at high temperature.
From a renormalization group analysis we show that at zero temperature, either
for small or large magnetic fields, and for a fixed transferred momentum $Q^2$,
$\alpha_s$ grows with the field strength with respect to its vacuum value.
However, at high temperature and also for a fixed value of $Q^2$ we find two
different cases: When the magnetic field is even larger than the squared
temperature, $\alpha_s$ also grows with the field strength. On the contrary,
when the squared temperature is larger than the magnetic field, a turnover
behavior occurs and $\alpha_s$ decreases with the field strength. This
thermo-magnetic behavior of $\alpha_s$ can help explain the inverse magnetic
catalysis phenomenon found by lattice QCD calculations.
| [
{
"created": "Mon, 21 May 2018 17:44:39 GMT",
"version": "v1"
},
{
"created": "Fri, 25 May 2018 19:40:23 GMT",
"version": "v2"
}
] | 2018-08-29 | [
[
"Ayala",
"Alejandro",
""
],
[
"Dominguez",
"C. A.",
""
],
[
"Hernandez-Ortiz",
"Saul",
""
],
[
"Hernandez",
"L. A.",
""
],
[
"Loewe",
"M.",
""
],
[
"Paret",
"D. Manreza",
""
],
[
"Zamora",
"R.",
""
]
] | We study the one-loop gluon polarization tensor at zero and finite temperature in the presence of a magnetic field, to extract the thermo-magnetic evolution of the strong coupling $\alpha_s$. We analyze four distinct regimes, to wit, the small and large field cases, both at zero and at high temperature. From a renormalization group analysis we show that at zero temperature, either for small or large magnetic fields, and for a fixed transferred momentum $Q^2$, $\alpha_s$ grows with the field strength with respect to its vacuum value. However, at high temperature and also for a fixed value of $Q^2$ we find two different cases: When the magnetic field is even larger than the squared temperature, $\alpha_s$ also grows with the field strength. On the contrary, when the squared temperature is larger than the magnetic field, a turnover behavior occurs and $\alpha_s$ decreases with the field strength. This thermo-magnetic behavior of $\alpha_s$ can help explain the inverse magnetic catalysis phenomenon found by lattice QCD calculations. |
hep-ph/9402256 | Jochen Rau | Jochen Rau (Duke U.) | Pair Production in the Quantum Boltzmann Equation | 13 pages + 2 PostScript figures, LaTeX, DUKE-TH-93-55 | Phys.Rev. D50 (1994) 6911-6916 | 10.1103/PhysRevD.50.6911 | null | hep-ph hep-th nucl-th | null | A source term in the quantum Boltzmann equation, which accounts for the
spontaneous creation of $e^+e^-$-pairs in external electric fields, is derived
from first principles and evaluated numerically. Careful analysis of time
scales reveals that this source term is generally non-Markovian. This implies
in particular that there may be temporary violations of the $H$-theorem.
| [
{
"created": "Wed, 9 Feb 1994 17:19:40 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Rau",
"Jochen",
"",
"Duke U."
]
] | A source term in the quantum Boltzmann equation, which accounts for the spontaneous creation of $e^+e^-$-pairs in external electric fields, is derived from first principles and evaluated numerically. Careful analysis of time scales reveals that this source term is generally non-Markovian. This implies in particular that there may be temporary violations of the $H$-theorem. |
1808.03720 | Jonathan Rosner | Michael Gronau, Jonathan L. Rosner, and Charles G. Wohl | Addendum to "Overview of $\Lambda_c$ decays'' | 5 pages, 2 figures. Minor corrections to title, abstract, and
introduction | Phys. Rev. D 98, 073003 (2018) | 10.1103/PhysRevD.98.073003 | EFI 18-10, TECHNION-2018-PH-6 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An earlier analysis of observed and anticipated $\Lambda_c$ decays [M. Gronau
and J. L. Rosner, Phys.\ Rev.\ D {\bf 97}, 116015 (2018)] is provided with a
table of inputs and a figure denoting branching fractions. This addendum is
based on the 2018 Particle Data Group compilation and employs a statistical
isospin model to estimate branching fractions for as-yet-unseen decay modes.
| [
{
"created": "Fri, 10 Aug 2018 22:18:22 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Aug 2018 21:17:16 GMT",
"version": "v2"
},
{
"created": "Fri, 21 Sep 2018 20:34:46 GMT",
"version": "v3"
}
] | 2018-10-17 | [
[
"Gronau",
"Michael",
""
],
[
"Rosner",
"Jonathan L.",
""
],
[
"Wohl",
"Charles G.",
""
]
] | An earlier analysis of observed and anticipated $\Lambda_c$ decays [M. Gronau and J. L. Rosner, Phys.\ Rev.\ D {\bf 97}, 116015 (2018)] is provided with a table of inputs and a figure denoting branching fractions. This addendum is based on the 2018 Particle Data Group compilation and employs a statistical isospin model to estimate branching fractions for as-yet-unseen decay modes. |
hep-ph/0406312 | Igor Strakovsky | Ya.I. Azimov (PNPI, JLab), I.I. Strakovsky (GWU) | Resonances, and mechanisms of Theta-production | 6 pages | Phys.Rev.C70:035210,2004 | 10.1103/PhysRevC.70.035210 | null | hep-ph hep-ex nucl-ex nucl-th | null | After explaining necessity of exotic hadrons, we discuss mechanisms which
could determine production of the exotic Theta-baryon. A possible important
role of resonances (producing the Theta in real or virtual decays) is
emphasized for various processes. Several experimental directions for studies
of such resonances, and the Theta itself, are suggested. We briefly discuss
also recent negative results on the Theta-baryon.
| [
{
"created": "Mon, 28 Jun 2004 19:53:39 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Azimov",
"Ya. I.",
"",
"PNPI, JLab"
],
[
"Strakovsky",
"I. I.",
"",
"GWU"
]
] | After explaining necessity of exotic hadrons, we discuss mechanisms which could determine production of the exotic Theta-baryon. A possible important role of resonances (producing the Theta in real or virtual decays) is emphasized for various processes. Several experimental directions for studies of such resonances, and the Theta itself, are suggested. We briefly discuss also recent negative results on the Theta-baryon. |
hep-ph/0506098 | Namit Mahajan | Namit Mahajan (Harish-Chandra Res. Inst.) | Revisiting 5D chiral symmetry breaking and holographic QCD models | Latex, 9 pages including 6eps figures. More discussion added and
minor rewording done. To appear in PLB | Phys.Lett. B623 (2005) 119-125 | 10.1016/j.physletb.2005.07.049 | null | hep-ph hep-th | null | We take a closer look at the recently discussed models of hadrons based on
holographic ideas and chiral symmetry breaking in five dimensions. We study the
two point correlator in detail and look at the field theoretic properties
needed to be satisfied by the correlator. It is shown that the spectral density
becomes negative, violating the basic requirements for the Kallen-Lehmann
representation. We briefly discuss the implications of this violation of the
positivity of the spectral density and also discuss possible origin of such a
violation in these models. Put simply this means that such models are not
physical descriptions of the hadron spectrum.
| [
{
"created": "Fri, 10 Jun 2005 03:33:08 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Jul 2005 09:34:04 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Mahajan",
"Namit",
"",
"Harish-Chandra Res. Inst."
]
] | We take a closer look at the recently discussed models of hadrons based on holographic ideas and chiral symmetry breaking in five dimensions. We study the two point correlator in detail and look at the field theoretic properties needed to be satisfied by the correlator. It is shown that the spectral density becomes negative, violating the basic requirements for the Kallen-Lehmann representation. We briefly discuss the implications of this violation of the positivity of the spectral density and also discuss possible origin of such a violation in these models. Put simply this means that such models are not physical descriptions of the hadron spectrum. |
1801.09506 | Jan Kalinowski | Abdelhak Djouadi, Jan Kalinowski, Margarete Muehlleitner, Michael
Spira | HDECAY: Twenty++ Years After | LaTeX, 41 pages | null | 10.1016/j.cpc.2018.12.010 | CERN-TH-2017-262, LPT-Orsay-18-04, KA-TP-03-2018, PSI-PR-18-02 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The program HDECAY determines the partial decay widths and branching ratios
of the Higgs bosons within the Standard Model with three and four generations
of fermions, including the case when the Higgs couplings are rescaled, a
general two--Higgs doublet model where the Higgs sector is extended and
incorporates five physical states and its most studied incarnation, the minimal
supersymmetric Standard Model (MSSM). The program addresses all decay channels
including the dominant higher-order effects such as radiative corrections and
multi-body channels. Since the first launch of the program, more than twenty
years ago, important aspects and new ingredients have been incorporated. In
this update of the program description, some of the developments are summarized
while others are discussed in some detail.
| [
{
"created": "Mon, 29 Jan 2018 13:57:13 GMT",
"version": "v1"
}
] | 2019-03-27 | [
[
"Djouadi",
"Abdelhak",
""
],
[
"Kalinowski",
"Jan",
""
],
[
"Muehlleitner",
"Margarete",
""
],
[
"Spira",
"Michael",
""
]
] | The program HDECAY determines the partial decay widths and branching ratios of the Higgs bosons within the Standard Model with three and four generations of fermions, including the case when the Higgs couplings are rescaled, a general two--Higgs doublet model where the Higgs sector is extended and incorporates five physical states and its most studied incarnation, the minimal supersymmetric Standard Model (MSSM). The program addresses all decay channels including the dominant higher-order effects such as radiative corrections and multi-body channels. Since the first launch of the program, more than twenty years ago, important aspects and new ingredients have been incorporated. In this update of the program description, some of the developments are summarized while others are discussed in some detail. |
hep-ph/0209355 | Alexei Yu. Illarionov | Alexei Yu. Illarionov, Anatoli G. Litvinenko, Gennady I. Lykasov | Probing the deuteron structure at small N-N distances by cumulative pion
production | 3 pages, 2 postscript figures; to appear in the proceedings of
Conference on Quarks and Nuclear Physics (QNP 2002), Julich, Germany, 9-14
Jun 2002 | null | 10.1140/epja/i2002-10224-4 | null | hep-ph nucl-th | null | The fragmentation of deuterons into pions emitted forward in the kinematic
region forbidden for free nucleon-nucleon collisions is analyzed. It is shown
that the inclusion of the non-nucleonic degrees of freedom in a deuteron
results in a satisfactory description of the data for the inclusive pion
spectrum and improves the description of the data about $T_{20}$. According to
the data, $T_{20}$ has very small positive values, less than 0.2, which
contradicts the theoretical calculations ignoring these degrees of freedom.
| [
{
"created": "Mon, 30 Sep 2002 05:12:51 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Illarionov",
"Alexei Yu.",
""
],
[
"Litvinenko",
"Anatoli G.",
""
],
[
"Lykasov",
"Gennady I.",
""
]
] | The fragmentation of deuterons into pions emitted forward in the kinematic region forbidden for free nucleon-nucleon collisions is analyzed. It is shown that the inclusion of the non-nucleonic degrees of freedom in a deuteron results in a satisfactory description of the data for the inclusive pion spectrum and improves the description of the data about $T_{20}$. According to the data, $T_{20}$ has very small positive values, less than 0.2, which contradicts the theoretical calculations ignoring these degrees of freedom. |
1701.01453 | Alessandro Strumia | Giulio Maria Pelaggi, Francesco Sannino, Alessandro Strumia, Elena
Vigiani | Naturalness of asymptotically safe Higgs | 17 pages. v2: final version; extra argument in the conclusions makes
obvious why our claims are correct | null | null | CERN-PH-TH-2017-001, CP3-Origins-2017-001, IFUP-TH/2017 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We extend the list of theories featuring a rigorous interacting ultraviolet
fixed point by constructing the first theory featuring a Higgs-like scalar with
gauge, Yukawa and quartic interactions. We show that the theory enters a
perturbative asymptotically safe regime at energies above a physical scale
$\Lambda$. We determine the salient properties of the theory and use it as a
concrete example to test whether scalars masses unavoidably receive quantum
correction of order $\Lambda$. Having at our dispose a calculable model
allowing us to precisely relate the IR and UV of the theory we demonstrate that
the scalars can be lighter than $\Lambda$. Although we do not have an answer to
whether the Standard Model hypercharge coupling growth towards a Landau pole at
around $\Lambda \sim 10^{40}$ GeV can be tamed by non-perturbative asymptotic
safety, our results indicate that such a possibility is worth exploring. In
fact, if successful, it might also offer an explanation for the unbearable
lightness of the Higgs.
| [
{
"created": "Thu, 5 Jan 2017 19:07:27 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Sep 2017 11:56:56 GMT",
"version": "v2"
}
] | 2017-09-28 | [
[
"Pelaggi",
"Giulio Maria",
""
],
[
"Sannino",
"Francesco",
""
],
[
"Strumia",
"Alessandro",
""
],
[
"Vigiani",
"Elena",
""
]
] | We extend the list of theories featuring a rigorous interacting ultraviolet fixed point by constructing the first theory featuring a Higgs-like scalar with gauge, Yukawa and quartic interactions. We show that the theory enters a perturbative asymptotically safe regime at energies above a physical scale $\Lambda$. We determine the salient properties of the theory and use it as a concrete example to test whether scalars masses unavoidably receive quantum correction of order $\Lambda$. Having at our dispose a calculable model allowing us to precisely relate the IR and UV of the theory we demonstrate that the scalars can be lighter than $\Lambda$. Although we do not have an answer to whether the Standard Model hypercharge coupling growth towards a Landau pole at around $\Lambda \sim 10^{40}$ GeV can be tamed by non-perturbative asymptotic safety, our results indicate that such a possibility is worth exploring. In fact, if successful, it might also offer an explanation for the unbearable lightness of the Higgs. |
hep-ph/9510422 | Zhen Cao | Zhen Cao and Rudolph C. Hwa | Chaotic Behavior of Particle Production in Branching Processes | 18 pages, latex, 15 figures in uuencode ps files; hard copy sent upon
request to hwa@oregon.uoregon.edu | Phys.Rev.D53:6608-6618,1996 | 10.1103/PhysRevD.53.6608 | OITS-586 | hep-ph nucl-th | null | The notion of chaotic behavior is examined for particle production in
branching processes. Two types of branching are considered: non-Abelian gauge
interaction and an Abelian cascade model. Properties of the production
processes are investigated by Monte Carlo stimulation. The ``temporal''
behavior is studied by following the fluctuations in the multiplicities of each
generation as the branching evolves. The ``spatial'' behavior is described in
terms of the fluctuations of the normalized factorial moments from event to
event. The information dimension and a new entropy index are determined. When
all the measures are taken together, they collectively give a strong suggestion
that the QCD branching process is chaotic, while the Abelian cascade model is
not.
| [
{
"created": "Thu, 26 Oct 1995 19:32:09 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Cao",
"Zhen",
""
],
[
"Hwa",
"Rudolph C.",
""
]
] | The notion of chaotic behavior is examined for particle production in branching processes. Two types of branching are considered: non-Abelian gauge interaction and an Abelian cascade model. Properties of the production processes are investigated by Monte Carlo stimulation. The ``temporal'' behavior is studied by following the fluctuations in the multiplicities of each generation as the branching evolves. The ``spatial'' behavior is described in terms of the fluctuations of the normalized factorial moments from event to event. The information dimension and a new entropy index are determined. When all the measures are taken together, they collectively give a strong suggestion that the QCD branching process is chaotic, while the Abelian cascade model is not. |
1710.10850 | Chao Wang | Chao Wang, Liang-Liang Liu, Xian-Wei Kang, Xin-Heng Guo, and Rui-Wu
Wang | Possible open-charmed pentaquark molecule $\Omega_c(3188)$ --- the $D
\Xi$ bound state --- in the Bethe-Salpeter formalism | 8 pages, 4 figures, accepted by Eur. Phys. J. C | Eur. Phys. J. C (2018) 78: 407 | 10.1140/epjc/s10052-018-5874-1 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the $S$-wave $D\Xi$ bound state in the Bethe-Salpeter formalism in
the ladder and instantaneous approximations. With the kernel generated by the
hadronic effective Lagrangian, two open-charmed bound states, which quantum
numbers are $I=0$, $J^P=(\frac{1}{2})^-$ and $I=1$, $J^P=(\frac{1}{2})^-$,
respectively, are predicted as new candidates of hadronic pentaquark molecules
in our formalism. If existing, they could contribute to the broad 3188 eV
structure near the five new narrow $\Omega_c$ states observed recently by the
LHCb Collaboration.
| [
{
"created": "Mon, 30 Oct 2017 10:22:21 GMT",
"version": "v1"
},
{
"created": "Sat, 5 May 2018 01:12:44 GMT",
"version": "v2"
}
] | 2018-05-29 | [
[
"Wang",
"Chao",
""
],
[
"Liu",
"Liang-Liang",
""
],
[
"Kang",
"Xian-Wei",
""
],
[
"Guo",
"Xin-Heng",
""
],
[
"Wang",
"Rui-Wu",
""
]
] | We study the $S$-wave $D\Xi$ bound state in the Bethe-Salpeter formalism in the ladder and instantaneous approximations. With the kernel generated by the hadronic effective Lagrangian, two open-charmed bound states, which quantum numbers are $I=0$, $J^P=(\frac{1}{2})^-$ and $I=1$, $J^P=(\frac{1}{2})^-$, respectively, are predicted as new candidates of hadronic pentaquark molecules in our formalism. If existing, they could contribute to the broad 3188 eV structure near the five new narrow $\Omega_c$ states observed recently by the LHCb Collaboration. |
2405.18599 | Henrique Boschi-Filho | Rafael A. Costa-Silva and Henrique Boschi-Filho | Anomalous and linear holographic hard wall models for light unflavored
mesons | 20 pages, 3 figures, 4 tables | null | null | null | hep-ph hep-th | http://creativecommons.org/licenses/by/4.0/ | In this work we consider anomalous and linear holographic hard wall (HW)
models for light unflavored mesons inspired by the AdS/CFT correspondence. The
anomalous dimensions depend on the logarithm of the spin $S$ of the meson state
and come from a semiclassical analysis of gauge/string duality. The anomalous
HW model produces very good masses and good Regge trajectories for mesons
compared with PDG data. Inspired by this anomalous HW model we also propose a
phenomenological modification of the dimension of the boundary operators such
that the model produces asymptotic linear Regge trajectories.
| [
{
"created": "Tue, 28 May 2024 21:26:51 GMT",
"version": "v1"
}
] | 2024-05-30 | [
[
"Costa-Silva",
"Rafael A.",
""
],
[
"Boschi-Filho",
"Henrique",
""
]
] | In this work we consider anomalous and linear holographic hard wall (HW) models for light unflavored mesons inspired by the AdS/CFT correspondence. The anomalous dimensions depend on the logarithm of the spin $S$ of the meson state and come from a semiclassical analysis of gauge/string duality. The anomalous HW model produces very good masses and good Regge trajectories for mesons compared with PDG data. Inspired by this anomalous HW model we also propose a phenomenological modification of the dimension of the boundary operators such that the model produces asymptotic linear Regge trajectories. |
0902.0502 | Yuri Andreev | Yu. M. Andreev, N. V. Krasnikov and A. N. Toropin (Institute for
Nuclear Research RAS, Moscow, Russia) | The MSSM with Large Gluino Mass | 9 pages, 4 figures | Mod.Phys.Lett.A24:1317-1324,2009 | 10.1142/S0217732309030771 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the Minimal Supersymmetric Standard Model (MSSM) with large gluino
mass m_{\tilde{g}} >> 1 TeV. In particular, we discuss the LHC supersymmetry
discovery signatures with n leptons + jets + E^{miss}_T, n >= 0 for the MSSM
with large gluino mass. We show that for some relations among squark and
neutralino masses leptonic signatures with n leptons + jets + E^{miss}_T, n >=
1 do not allow to discover supersymmetry at the LHC and the only supersymmetry
discovery signature remains the signature with no leptons + jets + E^{miss}_T.
Moreover, for LSP mass close to squark masses the LHC discovery potential for
this signature is strongly reduced.
| [
{
"created": "Tue, 3 Feb 2009 13:25:16 GMT",
"version": "v1"
}
] | 2010-04-21 | [
[
"Andreev",
"Yu. M.",
"",
"Institute for\n Nuclear Research RAS, Moscow, Russia"
],
[
"Krasnikov",
"N. V.",
"",
"Institute for\n Nuclear Research RAS, Moscow, Russia"
],
[
"Toropin",
"A. N.",
"",
"Institute for\n Nuclear Research RAS, Moscow, Russia"
]
] | We study the Minimal Supersymmetric Standard Model (MSSM) with large gluino mass m_{\tilde{g}} >> 1 TeV. In particular, we discuss the LHC supersymmetry discovery signatures with n leptons + jets + E^{miss}_T, n >= 0 for the MSSM with large gluino mass. We show that for some relations among squark and neutralino masses leptonic signatures with n leptons + jets + E^{miss}_T, n >= 1 do not allow to discover supersymmetry at the LHC and the only supersymmetry discovery signature remains the signature with no leptons + jets + E^{miss}_T. Moreover, for LSP mass close to squark masses the LHC discovery potential for this signature is strongly reduced. |
1911.12244 | Matthias Vereecken | Matthias Vereecken | Aspects of astrophysical particle production and beyond the Standard
Model phenomenology | PhD thesis, 463 pages. Based on the publications arXiv:1506.08803,
arXiv:1608.00028 and arXiv:1612.02648, which have been updated using more
recent data, as well as currently unpublished work on obscured neutrino
sources (Chapter 4) | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This PhD thesis deals with various aspects of (astro)particle physics
phenomenology and consists out of two parts: beyond the Standard Model physics
and neutrino astronomy. In the first part, I focus on beyond the Standard Model
physics at the Large Hadron collider. Concretely, I discuss the interpretation
of a 2015 excess seen by ATLAS in events with jets, missing transverse momentum
and 2 same-flavour, opposite-charge leptons within a model of gauge-mediated
supersymmetry breaking. Our model, which features supersymmetry breaking in
multiple hidden sectors, was able to explain the 2015 data because of the
appearance of an additional massive neutral particle at the bottom of the
spectrum, with couplings dictated by supersymmetry. However, using more recent
data, I show that this specific implementation of the model is now ruled out.
In the second part, I focus on astroparticle physics and neutrino astronomy.
This part consists of two projects. The first and largest of these investigates
the possibility that the neutrinos seen by IceCube are produced by sources
obscured by matter. We show that, in this case, existing bounds from the
extragalactic gamma-ray background can be evaded. In addition, we apply our
model to a set of sources selected for possible obscuration and obtain relevant
bounds on the parameter space. In the final project, I investigate current
constraints on neutrino emission from binary black hole mergers. While no such
neutrinos are typically expected, current constraints are not yet able to rule
out a substantial contribution of such events to the astrophysical neutrino
flux. I show that in the near future, this possibility will be constrained.
Both parts are preceded by an extensive introduction and review of their
respective fields, written to be of general interest.
| [
{
"created": "Tue, 26 Nov 2019 17:41:43 GMT",
"version": "v1"
}
] | 2019-11-28 | [
[
"Vereecken",
"Matthias",
""
]
] | This PhD thesis deals with various aspects of (astro)particle physics phenomenology and consists out of two parts: beyond the Standard Model physics and neutrino astronomy. In the first part, I focus on beyond the Standard Model physics at the Large Hadron collider. Concretely, I discuss the interpretation of a 2015 excess seen by ATLAS in events with jets, missing transverse momentum and 2 same-flavour, opposite-charge leptons within a model of gauge-mediated supersymmetry breaking. Our model, which features supersymmetry breaking in multiple hidden sectors, was able to explain the 2015 data because of the appearance of an additional massive neutral particle at the bottom of the spectrum, with couplings dictated by supersymmetry. However, using more recent data, I show that this specific implementation of the model is now ruled out. In the second part, I focus on astroparticle physics and neutrino astronomy. This part consists of two projects. The first and largest of these investigates the possibility that the neutrinos seen by IceCube are produced by sources obscured by matter. We show that, in this case, existing bounds from the extragalactic gamma-ray background can be evaded. In addition, we apply our model to a set of sources selected for possible obscuration and obtain relevant bounds on the parameter space. In the final project, I investigate current constraints on neutrino emission from binary black hole mergers. While no such neutrinos are typically expected, current constraints are not yet able to rule out a substantial contribution of such events to the astrophysical neutrino flux. I show that in the near future, this possibility will be constrained. Both parts are preceded by an extensive introduction and review of their respective fields, written to be of general interest. |
1512.00471 | Peter Cox | Peter Cox, Anibal D. Medina, Tirtha Sankar Ray, Andrew Spray | Novel Collider and Dark Matter Phenomenology of a Top-philic Z' | 30 pages, 11 figures; v2: version published in JHEP | JHEP 06 (2016) 110 | 10.1007/JHEP06(2016)110 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider extending the Standard Model by including an additional Abelian
gauge group broken at low energies under which the right-handed top quark is
the only effectively charged Standard Model fermion. The associated gauge boson
$(Z')$ is then naturally top-philic and couples only to the rest of the SM
particle content at loop-level or via kinetic mixing with the hypercharge gauge
boson which is assumed to be small. Working at the effective theory level, we
demonstrate that such a minimal extension allows for an improved fitting of the
$\sim 2\sigma$ excess observed in $t\bar{t}h$ searches at the LHC in a region
of parameter space that satisfies existing collider constraints. We also
present the reach of the LHC at 13 TeV in constraining the relevant region of
parameter space. Additionally we show that within the same framework a suitably
chosen fermion charged only under the exotic Abelian group can, in the region
of parameter space preferred by the $\bar{t}th$ measurements, simultaneously
explain the dark matter relic density and the $\gamma$-ray excess at the
galactic center observed by the Fermi-LAT experiment.
| [
{
"created": "Tue, 1 Dec 2015 21:00:11 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Jul 2016 04:53:43 GMT",
"version": "v2"
}
] | 2016-07-07 | [
[
"Cox",
"Peter",
""
],
[
"Medina",
"Anibal D.",
""
],
[
"Ray",
"Tirtha Sankar",
""
],
[
"Spray",
"Andrew",
""
]
] | We consider extending the Standard Model by including an additional Abelian gauge group broken at low energies under which the right-handed top quark is the only effectively charged Standard Model fermion. The associated gauge boson $(Z')$ is then naturally top-philic and couples only to the rest of the SM particle content at loop-level or via kinetic mixing with the hypercharge gauge boson which is assumed to be small. Working at the effective theory level, we demonstrate that such a minimal extension allows for an improved fitting of the $\sim 2\sigma$ excess observed in $t\bar{t}h$ searches at the LHC in a region of parameter space that satisfies existing collider constraints. We also present the reach of the LHC at 13 TeV in constraining the relevant region of parameter space. Additionally we show that within the same framework a suitably chosen fermion charged only under the exotic Abelian group can, in the region of parameter space preferred by the $\bar{t}th$ measurements, simultaneously explain the dark matter relic density and the $\gamma$-ray excess at the galactic center observed by the Fermi-LAT experiment. |
hep-ph/0111391 | Ma Jian-ping | J.P.Ma and J.S. Xu | Soft Gluon Approach for Diffractive Photoproduction of J/psi | 25 pages, 6 figures. Tiny changes in two figures, conclusion and text
unchanged, accpeted by Nucl. Phys. B | Nucl.Phys. B640 (2002) 283-308 | 10.1016/S0550-3213(02)00500-X | As-ITP-2001-018 | hep-ph hep-ex | null | We study diffractive photoproduction of $J/\psi$ by taking the charm quark as
a heavy quark. A description of nonperturbative effect related to $J/\psi$ can
be made by using NRQCD. In the forward region of the kinematics, the
interaction between the $c\bar c$-pair and the initial hadron is due to
exchange of soft gluons. The effect of the exchange can be studied by using the
expansion in the inverse of the quark mass $m_c$. At the leading order we find
that the nonperturbative effect related to the initial hadron is represented by
a matrix element of field strength operators, which are separated in the moving
direction of $J/\psi$ in the space-time. The S-matrix element is then obtained
without using perturbative QCD and the results are not based on any model.
Corrections to the results can be systematically added. Keeping the dominant
contribution of the S-matrix element in the large energy limit we find that the
imaginary part of the S-matrix element is related to the gluon distribution for
$x\to 0$ with a reasonable assumption, the real part can be obtained with
another approximation or with dispersion relation. Our approach is different
than previous approaches and also our results are different than those in these
approaches. The differences are discussed in detail. A comparison with
experiment is also made and a qualitative agreement is found.
| [
{
"created": "Thu, 29 Nov 2001 16:45:30 GMT",
"version": "v1"
},
{
"created": "Sat, 9 Mar 2002 02:38:16 GMT",
"version": "v2"
},
{
"created": "Mon, 13 May 2002 06:20:16 GMT",
"version": "v3"
},
{
"created": "Thu, 20 Jun 2002 01:00:19 GMT",
"version": "v4"
}
] | 2010-04-05 | [
[
"Ma",
"J. P.",
""
],
[
"Xu",
"J. S.",
""
]
] | We study diffractive photoproduction of $J/\psi$ by taking the charm quark as a heavy quark. A description of nonperturbative effect related to $J/\psi$ can be made by using NRQCD. In the forward region of the kinematics, the interaction between the $c\bar c$-pair and the initial hadron is due to exchange of soft gluons. The effect of the exchange can be studied by using the expansion in the inverse of the quark mass $m_c$. At the leading order we find that the nonperturbative effect related to the initial hadron is represented by a matrix element of field strength operators, which are separated in the moving direction of $J/\psi$ in the space-time. The S-matrix element is then obtained without using perturbative QCD and the results are not based on any model. Corrections to the results can be systematically added. Keeping the dominant contribution of the S-matrix element in the large energy limit we find that the imaginary part of the S-matrix element is related to the gluon distribution for $x\to 0$ with a reasonable assumption, the real part can be obtained with another approximation or with dispersion relation. Our approach is different than previous approaches and also our results are different than those in these approaches. The differences are discussed in detail. A comparison with experiment is also made and a qualitative agreement is found. |
hep-ph/0508272 | Arttu Rajantie | M. Donaire and A. Rajantie | Heavy cosmic strings | 4 pages, updated to match the published version | Phys.Rev. D73 (2006) 063517 | 10.1103/PhysRevD.73.063517 | DAMTP-2005-76, Imperial-TP | hep-ph astro-ph hep-lat hep-th | null | We argue that cosmic strings with high winding numbers generally form in
first-order gauge symmetry breaking phase transitions, and we demonstrate this
using computer simulations. These strings are heavier than single-winding
strings and therefore more easily observable. Their cosmological evolution may
also be very different.
| [
{
"created": "Fri, 26 Aug 2005 12:40:43 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Mar 2006 14:45:41 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Donaire",
"M.",
""
],
[
"Rajantie",
"A.",
""
]
] | We argue that cosmic strings with high winding numbers generally form in first-order gauge symmetry breaking phase transitions, and we demonstrate this using computer simulations. These strings are heavier than single-winding strings and therefore more easily observable. Their cosmological evolution may also be very different. |
2001.01490 | Luc Darm\'e | Luc Darm\'e, Sebastian A. R. Ellis, Tevong You | Light Dark Sectors through the Fermion Portal | 56 pages, 15 figures, DarkEFT public code available at
https://github.com/Luc-Darme/DarkEFT. References added, matches published
version on JHEP | null | 10.1007/JHEP07(2020)053 | CERN-TH-2020-003 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Pairs of Standard Model fermions form dimension-3 singlet operators that can
couple to new dark sector states. This "fermion portal" is to be contrasted
with the lower-dimensional Higgs, vector and neutrino singlet portals. We
characterise its distinct phenomenology and place effective field theory bounds
on this framework, focusing on the case of fermion portals to a pair of light
dark sector fermions. We obtain current and projected limits on the dimension-6
effective operator scale from a variety of meson decay experiments, missing
energy and long-lived particle searches at colliders, as well as astrophysical
and cosmological bounds. The DarkEFT public code is made available for
recasting these limits, which we illustrate with various examples including an
integrated-out heavy dark photon.
| [
{
"created": "Mon, 6 Jan 2020 11:28:18 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Jul 2020 10:04:28 GMT",
"version": "v2"
}
] | 2020-08-26 | [
[
"Darmé",
"Luc",
""
],
[
"Ellis",
"Sebastian A. R.",
""
],
[
"You",
"Tevong",
""
]
] | Pairs of Standard Model fermions form dimension-3 singlet operators that can couple to new dark sector states. This "fermion portal" is to be contrasted with the lower-dimensional Higgs, vector and neutrino singlet portals. We characterise its distinct phenomenology and place effective field theory bounds on this framework, focusing on the case of fermion portals to a pair of light dark sector fermions. We obtain current and projected limits on the dimension-6 effective operator scale from a variety of meson decay experiments, missing energy and long-lived particle searches at colliders, as well as astrophysical and cosmological bounds. The DarkEFT public code is made available for recasting these limits, which we illustrate with various examples including an integrated-out heavy dark photon. |
1106.4652 | Massimiliano Grazzini | S. Catani and M. Grazzini | Higgs boson production at hadron colliders: hard-collinear coefficients
at the NNLO | Few technical details added in Eqs.(34)-(38) and accompanying text,
typos corrected in Eq.(23) | null | 10.1140/epjc/s10052-012-2013-2 | ZU-TH 12/11 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the production of the Standard Model Higgs boson through the
gluon fusion mechanism in hadron collisions. We present the
next-to-next-to-leading order (NNLO) QCD result of the hard-collinear
coefficient function for the all-order resummation of logarithmically-enhanced
contributions at small transverse momentum. The coefficient function controls
NNLO contributions in resummed calculations at full next-to-next-to-leading
logarithmic accuracy. The same coefficient function is used in applications of
the subtraction method to perform fully-exclusive perturbative calculations up
to NNLO.
| [
{
"created": "Thu, 23 Jun 2011 08:49:28 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Jun 2012 13:27:52 GMT",
"version": "v2"
}
] | 2015-05-28 | [
[
"Catani",
"S.",
""
],
[
"Grazzini",
"M.",
""
]
] | We consider the production of the Standard Model Higgs boson through the gluon fusion mechanism in hadron collisions. We present the next-to-next-to-leading order (NNLO) QCD result of the hard-collinear coefficient function for the all-order resummation of logarithmically-enhanced contributions at small transverse momentum. The coefficient function controls NNLO contributions in resummed calculations at full next-to-next-to-leading logarithmic accuracy. The same coefficient function is used in applications of the subtraction method to perform fully-exclusive perturbative calculations up to NNLO. |
1208.0032 | Gary Steigman | Gary Steigman | Neutrinos And Big Bang Nucleosynthesis | Invited Review article for the Special Issue on Neutrino Physics,
Advances in High Energy Physics, 25 pages, 10 figures | Advances in High Energy Physics, 2012 (2012) 268321 | 10.1155/2012/268321 | null | hep-ph astro-ph.CO nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | According to the standard models of particle physics and cosmology, there
should be a background of cosmic neutrinos in the present Universe, similar to
the cosmic microwave photon background. The weakness of the weak interactions
renders this neutrino background undetectable with current technology. The
cosmic neutrino background can, however, be probed indirectly through its
cosmological effects on big bang nucleosynthesis (BBN) and the cosmic microwave
background (CMB) radiation. In this BBN review, focused on neutrinos and, more
generally on dark radiation, the BBN constraints on the number of "equivalent
neutrinos" (dark radiation), on the baryon asymmetry (baryon density), and on a
possible lepton asymmetry (neutrino degeneracy) are reviewed and updated. The
BBN constraints on dark radiation and on the baryon density following from
considerations of the primordial abundances of deuterium and helium-4 are in
excellent agreement with the complementary results from the CMB, providing a
suggestive, but currently inconclusive, hint of the presence of dark radiation
and, they constrain any lepton asymmetry. For all the cases considered here
there is a "lithium problem": the BBN-predicted lithium abundance exceeds the
observationally inferred primordial value by a factor of ~3.
| [
{
"created": "Tue, 31 Jul 2012 21:10:54 GMT",
"version": "v1"
}
] | 2013-05-27 | [
[
"Steigman",
"Gary",
""
]
] | According to the standard models of particle physics and cosmology, there should be a background of cosmic neutrinos in the present Universe, similar to the cosmic microwave photon background. The weakness of the weak interactions renders this neutrino background undetectable with current technology. The cosmic neutrino background can, however, be probed indirectly through its cosmological effects on big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) radiation. In this BBN review, focused on neutrinos and, more generally on dark radiation, the BBN constraints on the number of "equivalent neutrinos" (dark radiation), on the baryon asymmetry (baryon density), and on a possible lepton asymmetry (neutrino degeneracy) are reviewed and updated. The BBN constraints on dark radiation and on the baryon density following from considerations of the primordial abundances of deuterium and helium-4 are in excellent agreement with the complementary results from the CMB, providing a suggestive, but currently inconclusive, hint of the presence of dark radiation and, they constrain any lepton asymmetry. For all the cases considered here there is a "lithium problem": the BBN-predicted lithium abundance exceeds the observationally inferred primordial value by a factor of ~3. |
1507.06424 | Gautam Bhattacharyya | Gautam Bhattacharyya and Dipankar Das | Scalar sector of Two-Higgs-Doublet models: A mini-review | 18 pages; Invited Review to be published in a special issue (theme
`Higgs') of PRAMANA | null | 10.1007/s12043-016-1252-4 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A vast literature on the theory and phenomenology of Two-Higgs-Doublet models
(2HDM) exists since long. However, the present situation demands a revisit of
some 2HDM properties. Now that a 125 GeV scalar resonance has been discovered
at the LHC, with its couplings to other particles showing increasing affinity
to the Standard Model Higgs-like behavior, the 2HDM parameter space is more
squeezed than ever. We briefly review the different parametrizations of the
2HDM potential and discuss the constraints on the parameter space arising from
the unitarity and stability of the potential together with constraints from the
oblique electroweak $T$-parameter. We also differentiate the consequences of
imposing a global continuous U(1) symmetry on the potential from a discrete
$Z_2$ symmetry.
| [
{
"created": "Thu, 23 Jul 2015 09:35:31 GMT",
"version": "v1"
}
] | 2016-09-21 | [
[
"Bhattacharyya",
"Gautam",
""
],
[
"Das",
"Dipankar",
""
]
] | A vast literature on the theory and phenomenology of Two-Higgs-Doublet models (2HDM) exists since long. However, the present situation demands a revisit of some 2HDM properties. Now that a 125 GeV scalar resonance has been discovered at the LHC, with its couplings to other particles showing increasing affinity to the Standard Model Higgs-like behavior, the 2HDM parameter space is more squeezed than ever. We briefly review the different parametrizations of the 2HDM potential and discuss the constraints on the parameter space arising from the unitarity and stability of the potential together with constraints from the oblique electroweak $T$-parameter. We also differentiate the consequences of imposing a global continuous U(1) symmetry on the potential from a discrete $Z_2$ symmetry. |
hep-ph/9505329 | Peter Cho | Peter Cho and Adam Leibovich | Color-octet quarkonia production | 23 pages, harvmac, 11 uuencoded figures | Phys.Rev.D53:150-162,1996 | 10.1103/PhysRevD.53.150 | CALT-68-1988 | hep-ph | null | Gluon fragmentation represents the dominant source of high energy prompt
quarkonia at hadron colliders. Fragmentation approximations break down,
however, when a quarkonium's transverse momentum becomes comparable to its
mass. In this paper, we identify a large class of color-octet diagrams that
mediate quarkonia production at all energies and reduce to the dominant set of
gluon fragmentation graphs in the high $p_\perp$ limit. They contribute to
quarkonia differential cross sections at the same order as color-singlet
diagrams and bring theoretical predictions for Upsilon and Psi production at
the Tevatron into agreement with experimental measurements. Using recent CDF
data, we extract numerical values for bottomonia and charmonia color-octet
matrix elements which are consistent with NRQCD scaling rules. We also find
that quarkonia generated via the color-octet mechanism are strongly polarized
at low as well as high energies. Spin alignment measurements can thus test the
color-octet quarkonia production picture.
| [
{
"created": "Wed, 17 May 1995 19:04:23 GMT",
"version": "v1"
}
] | 2010-11-19 | [
[
"Cho",
"Peter",
""
],
[
"Leibovich",
"Adam",
""
]
] | Gluon fragmentation represents the dominant source of high energy prompt quarkonia at hadron colliders. Fragmentation approximations break down, however, when a quarkonium's transverse momentum becomes comparable to its mass. In this paper, we identify a large class of color-octet diagrams that mediate quarkonia production at all energies and reduce to the dominant set of gluon fragmentation graphs in the high $p_\perp$ limit. They contribute to quarkonia differential cross sections at the same order as color-singlet diagrams and bring theoretical predictions for Upsilon and Psi production at the Tevatron into agreement with experimental measurements. Using recent CDF data, we extract numerical values for bottomonia and charmonia color-octet matrix elements which are consistent with NRQCD scaling rules. We also find that quarkonia generated via the color-octet mechanism are strongly polarized at low as well as high energies. Spin alignment measurements can thus test the color-octet quarkonia production picture. |
hep-ph/0203144 | Lokhtin | I.P.Lokhtin, L.I.Sarycheva, A.M.Snigirev | A method for analysing the jet azimuthal anisotropy in ultrarelativistic
heavy ion collisions | 11 pages including 1 figure, LaTeX, epsfig.sty | Phys.Lett. B537 (2002) 261-267 | 10.1016/S0370-2693(02)01913-5 | null | hep-ph | null | The azimuthal anisotropy of jet spectra due to energy loss of jet partons in
azimuthally non-symmetric volume of dense quark-gluon matter is considered for
semi-central nuclear interactions at collider energies. We develop the
techniques for event-by-event analysing the jet azimuthal anisotropy using
particle and energy elliptic flow, and suggest a method for calculation of
coefficient of jet azimuthal anisotropy without reconstruction of nuclear
reaction plane.
| [
{
"created": "Fri, 15 Mar 2002 12:28:47 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Apr 2002 11:28:09 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Lokhtin",
"I. P.",
""
],
[
"Sarycheva",
"L. I.",
""
],
[
"Snigirev",
"A. M.",
""
]
] | The azimuthal anisotropy of jet spectra due to energy loss of jet partons in azimuthally non-symmetric volume of dense quark-gluon matter is considered for semi-central nuclear interactions at collider energies. We develop the techniques for event-by-event analysing the jet azimuthal anisotropy using particle and energy elliptic flow, and suggest a method for calculation of coefficient of jet azimuthal anisotropy without reconstruction of nuclear reaction plane. |
2111.08027 | Adil Jueid | Genevi\`eve Belanger, Aoife Bharucha, Benjamin Fuks, Andreas Goudelis,
Jan Heisig, Adil Jueid, Andre Lessa, Kirtimaan A. Mohan, Giacomo Polesello,
Priscilla Pani, Alexander Pukhov, Dipan Sengupta, Jos\'e Zurita | Leptoquark manoeuvres in the dark: a simultaneous solution of the dark
matter problem and the $R_{D^{(*)}}$ anomalies | v2: 60 pages, minor changes, added references. Matches the published
version | null | 10.1007/JHEP02(2022)042 | KIAS-Q21013, MSUHEP-21-031, IFIC/21-46, TTK-21-44, P3H-21-091 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The measured branching fractions of $B$-mesons into leptonic final states
derived by the LHCb collaboration hint towards the breakdown of lepton flavour
universality. In this work we take at face value the so-called $R_{D^{(*)}}$
observables that are defined as the ratios of neutral $B$-meson charged-current
decays into a charged $D$-meson, a charged lepton and a neutrino final state in
the tau and muon channels. A well-studied and simple solution to this charged
current anomaly is to introduce a scalar leptoquark $S_1$ that couples to the
second and third generation of fermions. We investigate how $S_1$ can also
serve as a mediator between the Standard Model and a dark sector. We study this
scenario in detail and estimate the constraints arising from collider searches
for leptoquarks, collider searches for missing energy signals, direct detection
experiments and the dark matter relic abundance. We stress that the production
of a pair of leptoquarks that decays into different final states (i.e. the
commonly called "mixed" channels) provides critical information for identifying
the underlying dynamics, and we exemplify this by studying the $t \tau b \nu$
and the resonant $S_1$ plus missing energy channels. We find that direct
detection data provides non-negligible constraints on the leptoquark coupling
to the dark sector, which in turn affects the relic abundance. We also show
that the correct relic abundance can not only arise via standard freeze-out,
but also through conversion-driven freeze-out. We illustrate the rich
phenomenology of the model with a few selected benchmark points, providing a
broad stroke of the interesting connection between lepton flavour violation and
dark matter.
| [
{
"created": "Mon, 15 Nov 2021 19:00:05 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Feb 2022 10:18:20 GMT",
"version": "v2"
}
] | 2022-02-23 | [
[
"Belanger",
"Geneviève",
""
],
[
"Bharucha",
"Aoife",
""
],
[
"Fuks",
"Benjamin",
""
],
[
"Goudelis",
"Andreas",
""
],
[
"Heisig",
"Jan",
""
],
[
"Jueid",
"Adil",
""
],
[
"Lessa",
"Andre",
""
],
[
"Mohan",
"Kirtimaan A.",
""
],
[
"Polesello",
"Giacomo",
""
],
[
"Pani",
"Priscilla",
""
],
[
"Pukhov",
"Alexander",
""
],
[
"Sengupta",
"Dipan",
""
],
[
"Zurita",
"José",
""
]
] | The measured branching fractions of $B$-mesons into leptonic final states derived by the LHCb collaboration hint towards the breakdown of lepton flavour universality. In this work we take at face value the so-called $R_{D^{(*)}}$ observables that are defined as the ratios of neutral $B$-meson charged-current decays into a charged $D$-meson, a charged lepton and a neutrino final state in the tau and muon channels. A well-studied and simple solution to this charged current anomaly is to introduce a scalar leptoquark $S_1$ that couples to the second and third generation of fermions. We investigate how $S_1$ can also serve as a mediator between the Standard Model and a dark sector. We study this scenario in detail and estimate the constraints arising from collider searches for leptoquarks, collider searches for missing energy signals, direct detection experiments and the dark matter relic abundance. We stress that the production of a pair of leptoquarks that decays into different final states (i.e. the commonly called "mixed" channels) provides critical information for identifying the underlying dynamics, and we exemplify this by studying the $t \tau b \nu$ and the resonant $S_1$ plus missing energy channels. We find that direct detection data provides non-negligible constraints on the leptoquark coupling to the dark sector, which in turn affects the relic abundance. We also show that the correct relic abundance can not only arise via standard freeze-out, but also through conversion-driven freeze-out. We illustrate the rich phenomenology of the model with a few selected benchmark points, providing a broad stroke of the interesting connection between lepton flavour violation and dark matter. |
2102.11346 | Greger Torgrimsson | Greger Torgrimsson | Resummation of quantum radiation reaction in plane waves | 7 pages, 4 figures | Phys. Rev. Lett. 127, 111602 (2021) | 10.1103/PhysRevLett.127.111602 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new approach to obtain the momentum expectation value of an
electron in a high-intensity laser, including multiple photon emissions and
loops. We find a recursive formula that allows us to obtain the
$\mathcal{O}(\alpha^n)$ term from $\mathcal{O}(\alpha^{n-1})$, which can also
be expressed as an integro-differential equation. In the classical limit we
obtain the solution to the Landau-Lifshitz equation to all orders. We show how
spin-dependent quantum radiation reaction can be obtained by resumming both the
energy expansion as well as the $\alpha$ expansion.
| [
{
"created": "Mon, 22 Feb 2021 20:39:51 GMT",
"version": "v1"
}
] | 2021-09-15 | [
[
"Torgrimsson",
"Greger",
""
]
] | We propose a new approach to obtain the momentum expectation value of an electron in a high-intensity laser, including multiple photon emissions and loops. We find a recursive formula that allows us to obtain the $\mathcal{O}(\alpha^n)$ term from $\mathcal{O}(\alpha^{n-1})$, which can also be expressed as an integro-differential equation. In the classical limit we obtain the solution to the Landau-Lifshitz equation to all orders. We show how spin-dependent quantum radiation reaction can be obtained by resumming both the energy expansion as well as the $\alpha$ expansion. |
1306.4581 | Massimiliano Grazzini | M. Grazzini and H. Sargsyan | Heavy-quark mass effects in Higgs boson production at the LHC | Minor modifications, results unchanged. Discussion on uncertainties
added. Version published on JHEP | JHEP 09 (2013) 129 | 10.1007/JHEP09(2013)129 | ZU-TH 10/13 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the impact of heavy-quark masses in Higgs boson production through
gluon fusion at the LHC. We extend previous computations of the fully
differential cross section and of the transverse momentum spectrum of the Higgs
boson by taking into account the finite top- and bottom-quark masses up to
O(alpha_S^3). We also discuss the issues arising when the heavy-quark mass is
much smaller than the Higgs mass. Our results are implemented in updated
versions of the HNNLO and HRes numerical programs.
| [
{
"created": "Wed, 19 Jun 2013 15:29:20 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Sep 2013 10:17:25 GMT",
"version": "v2"
}
] | 2015-06-16 | [
[
"Grazzini",
"M.",
""
],
[
"Sargsyan",
"H.",
""
]
] | We study the impact of heavy-quark masses in Higgs boson production through gluon fusion at the LHC. We extend previous computations of the fully differential cross section and of the transverse momentum spectrum of the Higgs boson by taking into account the finite top- and bottom-quark masses up to O(alpha_S^3). We also discuss the issues arising when the heavy-quark mass is much smaller than the Higgs mass. Our results are implemented in updated versions of the HNNLO and HRes numerical programs. |
hep-ph/9810363 | Theodore J. Allen | T.J. Allen, M.G. Olsson, S. Veseli | Adiabatic string shape for non-uniform rotation | 17 pages LaTeX, 4 figures. Version to appear in Phys Rev D | Phys.Rev. D59 (1999) 094011 | 10.1103/PhysRevD.59.094011 | MADPH-98-1086, FERMILAB-PUB-98/316-T | hep-ph hep-th | null | It is well known that a straight Nambu-Goto string is an exact solution of
the equations of motion when its end moves in a circular orbit. In this paper
we investigate the shape of a confining relativistic string for a general
motion of its end. We determine analytically the shape of the curved string to
leading order in deviation from straightness, and show that it reduces to an
expected non-relativistic result. We also demonstrate numerically that in
realistic meson models this deviation is always small. We further find that the
angular momentum and energy are the same as for the straight string, but that
the curved string has a small radial momentum not present in a straight string.
Our results justify the common assumption of straight strings usually made in
hadron models.
| [
{
"created": "Wed, 14 Oct 1998 21:31:45 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Feb 1999 22:27:27 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Allen",
"T. J.",
""
],
[
"Olsson",
"M. G.",
""
],
[
"Veseli",
"S.",
""
]
] | It is well known that a straight Nambu-Goto string is an exact solution of the equations of motion when its end moves in a circular orbit. In this paper we investigate the shape of a confining relativistic string for a general motion of its end. We determine analytically the shape of the curved string to leading order in deviation from straightness, and show that it reduces to an expected non-relativistic result. We also demonstrate numerically that in realistic meson models this deviation is always small. We further find that the angular momentum and energy are the same as for the straight string, but that the curved string has a small radial momentum not present in a straight string. Our results justify the common assumption of straight strings usually made in hadron models. |
hep-ph/0002247 | null | E.-M. Ilgenfritz, B. V. Martemyanov and M. Muller-Preussker | Field strength correlators in the instanton gas: The importance of the
two-instanton contribution | 20 pages, 3 figures | Phys.Rev. D62 (2000) 096004 | 10.1103/PhysRevD.62.096004 | null | hep-ph hep-lat | null | The field strength correlators at zero temperature are semi-classically
evaluated fitting the random instanton liquid model to lattice data for
quenched SU(3) lattice gauge theory. We restrict ourselves to the lowest order
in an instanton density expansion necessary to explain the difference between
transverse and longitudinal correlation functions. In the instanton-instanton
and instanton-antiinstanton contributions the Schwinger line factors neglected
in a previous analysis are numerically taken into account in a weighted Monte
Carlo evaluation. This leads to different estimates for instanton size and
density. A reasonable description of the correlators within the intermediate
range from 0.4 fm to 1 fm is obtained.
| [
{
"created": "Thu, 24 Feb 2000 08:59:07 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Ilgenfritz",
"E. -M.",
""
],
[
"Martemyanov",
"B. V.",
""
],
[
"Muller-Preussker",
"M.",
""
]
] | The field strength correlators at zero temperature are semi-classically evaluated fitting the random instanton liquid model to lattice data for quenched SU(3) lattice gauge theory. We restrict ourselves to the lowest order in an instanton density expansion necessary to explain the difference between transverse and longitudinal correlation functions. In the instanton-instanton and instanton-antiinstanton contributions the Schwinger line factors neglected in a previous analysis are numerically taken into account in a weighted Monte Carlo evaluation. This leads to different estimates for instanton size and density. A reasonable description of the correlators within the intermediate range from 0.4 fm to 1 fm is obtained. |
1406.5625 | Jos\'e Daniel Madrigal | M. Hentschinski, J.D. Madrigal, B. Murdaca and A. Sabio Vera | The quark induced Mueller-Tang jet impact factor at next-to-leading
order | 29 pages, many figures | null | 10.1016/j.nuclphysb.2014.08.010 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the NLO corrections for the quark induced forward production of a
jet with an associated rapidity gap. We make use of Lipatov's QCD high energy
effective action to calculate the real emission contributions to the so-called
Mueller-Tang impact factor. We combine them with the previously calculated
virtual corrections and verify ultraviolet and collinear finiteness of the
final result.
| [
{
"created": "Sat, 21 Jun 2014 15:07:07 GMT",
"version": "v1"
}
] | 2015-06-22 | [
[
"Hentschinski",
"M.",
""
],
[
"Madrigal",
"J. D.",
""
],
[
"Murdaca",
"B.",
""
],
[
"Vera",
"A. Sabio",
""
]
] | We present the NLO corrections for the quark induced forward production of a jet with an associated rapidity gap. We make use of Lipatov's QCD high energy effective action to calculate the real emission contributions to the so-called Mueller-Tang impact factor. We combine them with the previously calculated virtual corrections and verify ultraviolet and collinear finiteness of the final result. |
0711.2299 | Vesna Borka Jovanovi\'c | Vesna Borka Jovanovi\'c | Masses and Mixing of $c q \bar{q} \bar{q}$ Tetraquarks Using
Glozman-Riska Hyperfine Interaction | 10 pages, 6 tables, 6 figures. Accepted for publication in Phys. Rev.
D | Phys.Rev.D76:105011,2007 | 10.1103/PhysRevD.76.105011 | null | hep-ph | null | In this paper we perform a detailed study of the masses and mixing of the
single charmed scalar tetraquarks: $c q \bar{q} \bar{q}$. We also give a
systematic analysis of these tetraquark states by weight diagrams, quantum
numbers and flavor wave functions. Tetraquark masses are calculated using four
different fits. The following SU(3)$_\mathrm{F}$ representations are discussed:
$\bar{15}_\mathrm{S}$, $\bar{3}_\mathrm{S}$, $6_\mathrm{A}$ and
$\bar{3}_\mathrm{A}$. We use the flavor-spin Glozman-Riska interaction
Hamiltonian with SU(3) flavor symmetry breaking. There are 27 different
tetraquarks composed of a charm quark $c$ and of the three light flavors $u, d,
s$: 11 cryptoexotic (3 D$_\mathrm{s}^{+}$, 4 D$^{+}$, 4 D$^{0}$) and 16
explicit exotic states. We discuss D$_\mathrm{s}$ and its isospin partners in
the same multiplet, as well as all the other four-quark states. Some explicit
exotic states appear in the spectrum with the same masses as
D$_\mathrm{s}^{+}$(2632) in $\bar{15}_\mathrm{S}$ and with the same masses as
D$_\mathrm{s}^{+}$(2317) in $6_\mathrm{A}$ representation, which confirm the
tetraquark nature of these states.
| [
{
"created": "Wed, 14 Nov 2007 20:45:34 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Jovanović",
"Vesna Borka",
""
]
] | In this paper we perform a detailed study of the masses and mixing of the single charmed scalar tetraquarks: $c q \bar{q} \bar{q}$. We also give a systematic analysis of these tetraquark states by weight diagrams, quantum numbers and flavor wave functions. Tetraquark masses are calculated using four different fits. The following SU(3)$_\mathrm{F}$ representations are discussed: $\bar{15}_\mathrm{S}$, $\bar{3}_\mathrm{S}$, $6_\mathrm{A}$ and $\bar{3}_\mathrm{A}$. We use the flavor-spin Glozman-Riska interaction Hamiltonian with SU(3) flavor symmetry breaking. There are 27 different tetraquarks composed of a charm quark $c$ and of the three light flavors $u, d, s$: 11 cryptoexotic (3 D$_\mathrm{s}^{+}$, 4 D$^{+}$, 4 D$^{0}$) and 16 explicit exotic states. We discuss D$_\mathrm{s}$ and its isospin partners in the same multiplet, as well as all the other four-quark states. Some explicit exotic states appear in the spectrum with the same masses as D$_\mathrm{s}^{+}$(2632) in $\bar{15}_\mathrm{S}$ and with the same masses as D$_\mathrm{s}^{+}$(2317) in $6_\mathrm{A}$ representation, which confirm the tetraquark nature of these states. |
2104.12795 | Lara Mason | Alan S. Cornell, Aldo Deandrea, Thomas Flacke, Benjamin Fuks, Lara
Mason | Contact interactions and top-philic scalar dark matter | 27 pages, 12 figures. Version accepted for publication in JHEP | JHEP 07 (2021) 026 | 10.1007/JHEP07(2021)026 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the phenomenology of a scalar top-philic dark matter candidate
when adding a dimension-five contact interaction term, as motivated by possible
underlying extensions of the Standard Model such as composite Higgs models. We
show that the presence of contact interactions can have a major impact on the
dark matter relic density as well as on its direct and indirect detection
prospects, while the collider phenomenology of the model is unaffected. This
underlines the complementarity of collider and cosmological constraints on dark
matter models.
| [
{
"created": "Mon, 26 Apr 2021 18:00:15 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Jun 2021 16:41:21 GMT",
"version": "v2"
}
] | 2021-07-09 | [
[
"Cornell",
"Alan S.",
""
],
[
"Deandrea",
"Aldo",
""
],
[
"Flacke",
"Thomas",
""
],
[
"Fuks",
"Benjamin",
""
],
[
"Mason",
"Lara",
""
]
] | We investigate the phenomenology of a scalar top-philic dark matter candidate when adding a dimension-five contact interaction term, as motivated by possible underlying extensions of the Standard Model such as composite Higgs models. We show that the presence of contact interactions can have a major impact on the dark matter relic density as well as on its direct and indirect detection prospects, while the collider phenomenology of the model is unaffected. This underlines the complementarity of collider and cosmological constraints on dark matter models. |
1012.5065 | Sergey Afonin | S.S. Afonin | No-Wall Holographic Model for QCD | 10 pages, the paper is significantly modified, the relevance of dim2
operator is emphasized | null | 10.1142/S0217751X11053997 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new type of bottom-up holographic model describing the Regge
like spectrum of mesons. This type of spectrum emerges due to condensation of a
scalar field in the bulk anti-de Sitter space. The gauge invariance of the
action describing the vector mesons requires that the bulk scalar field must
correspond to an operator of canonical dimension two. This is not necessary for
the description of the scalar sector where the generation of the mass spectrum
can be directly related to the formation of gluon condensate in QCD. It is also
demonstrated that such an explicit introduction of local dim2 operator into the
model leads to disappearance of the corresponding contribution from the dim2
condensate in the power expansion of the gauge-invariant vector correlator as
required by QCD.
| [
{
"created": "Wed, 22 Dec 2010 18:17:34 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Dec 2010 19:10:59 GMT",
"version": "v2"
},
{
"created": "Wed, 2 Mar 2011 09:49:38 GMT",
"version": "v3"
},
{
"created": "Thu, 3 Mar 2011 07:28:48 GMT",
"version": "v4"
}
] | 2015-05-20 | [
[
"Afonin",
"S. S.",
""
]
] | We propose a new type of bottom-up holographic model describing the Regge like spectrum of mesons. This type of spectrum emerges due to condensation of a scalar field in the bulk anti-de Sitter space. The gauge invariance of the action describing the vector mesons requires that the bulk scalar field must correspond to an operator of canonical dimension two. This is not necessary for the description of the scalar sector where the generation of the mass spectrum can be directly related to the formation of gluon condensate in QCD. It is also demonstrated that such an explicit introduction of local dim2 operator into the model leads to disappearance of the corresponding contribution from the dim2 condensate in the power expansion of the gauge-invariant vector correlator as required by QCD. |
0806.3414 | Michelangelo Mangano | J. Ellis, G. Giudice, M.L. Mangano, I. Tkachev, U. Wiedemann | Review of the Safety of LHC Collisions | This revised version incorporates the "Addendum on strangelets" as
Appendix, and updates the bibliography | J.Phys.G35:115004,2008 | 10.1088/0954-3899/35/11/115004 | CERN-PH-TH/2008-136 | hep-ph hep-ex hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The safety of collisions at the Large Hadron Collider (LHC) was studied in
2003 by the LHC Safety Study Group, who concluded that they presented no
danger. Here we review their 2003 analysis in light of additional experimental
results and theoretical understanding, which enable us to confirm, update and
extend the conclusions of the LHC Safety Study Group. The LHC reproduces in the
laboratory, under controlled conditions, collisions at centre-of-mass energies
less than those reached in the atmosphere by some of the cosmic rays that have
been bombarding the Earth for billions of years. We recall the rates for the
collisions of cosmic rays with the Earth, Sun, neutron stars, white dwarfs and
other astronomical bodies at energies higher than the LHC. The stability of
astronomical bodies indicates that such collisions cannot be dangerous.
Specifically, we study the possible production at the LHC of hypothetical
objects such as vacuum bubbles, magnetic monopoles, microscopic black holes and
strangelets, and find no associated risks. Any microscopic black holes produced
at the LHC are expected to decay by Hawking radiation before they reach the
detector walls. If some microscopic black holes were stable, those produced by
cosmic rays would be stopped inside the Earth or other astronomical bodies. The
stability of astronomical bodies constrains strongly the possible rate of
accretion by any such microscopic black holes, so that they present no
conceivable danger. In the case of strangelets, the good agreement of
measurements of particle production at RHIC with simple thermodynamic models
constrains severely the production of strangelets in heavy-ion collisions at
the LHC, which also present no danger.
| [
{
"created": "Fri, 20 Jun 2008 15:30:29 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Sep 2008 14:21:37 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Ellis",
"J.",
""
],
[
"Giudice",
"G.",
""
],
[
"Mangano",
"M. L.",
""
],
[
"Tkachev",
"I.",
""
],
[
"Wiedemann",
"U.",
""
]
] | The safety of collisions at the Large Hadron Collider (LHC) was studied in 2003 by the LHC Safety Study Group, who concluded that they presented no danger. Here we review their 2003 analysis in light of additional experimental results and theoretical understanding, which enable us to confirm, update and extend the conclusions of the LHC Safety Study Group. The LHC reproduces in the laboratory, under controlled conditions, collisions at centre-of-mass energies less than those reached in the atmosphere by some of the cosmic rays that have been bombarding the Earth for billions of years. We recall the rates for the collisions of cosmic rays with the Earth, Sun, neutron stars, white dwarfs and other astronomical bodies at energies higher than the LHC. The stability of astronomical bodies indicates that such collisions cannot be dangerous. Specifically, we study the possible production at the LHC of hypothetical objects such as vacuum bubbles, magnetic monopoles, microscopic black holes and strangelets, and find no associated risks. Any microscopic black holes produced at the LHC are expected to decay by Hawking radiation before they reach the detector walls. If some microscopic black holes were stable, those produced by cosmic rays would be stopped inside the Earth or other astronomical bodies. The stability of astronomical bodies constrains strongly the possible rate of accretion by any such microscopic black holes, so that they present no conceivable danger. In the case of strangelets, the good agreement of measurements of particle production at RHIC with simple thermodynamic models constrains severely the production of strangelets in heavy-ion collisions at the LHC, which also present no danger. |
1102.0416 | Kazem Azizi | T. M. Aliev, K. Azizi, M. Savci, V. S. Zamiralov | Analysis of heavy spin--3/2 baryon--heavy spin--1/2 baryon--light vector
meson vertices in QCD | 17 Pages, 6 Figures and 4 Tables | Phys.Rev.D83:096007,2011 | 10.1103/PhysRevD.83.096007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The heavy spin--3/2 baryon--heavy spin--1/2 baryon vertices with light vector
mesons are studied within the light cone QCD sum rules method. These vertices
are parametrized in terms of three coupling constants. These couplings are
calculated for all possible transitions. It is shown that correlation functions
for these transitions are described by only one invariant function for every
Lorenz structure. The obtained relations between the correlation functions of
the different transitions are structure independent while explicit expressions
of invariant functions depend on the Lorenz structure.
| [
{
"created": "Wed, 2 Feb 2011 12:24:32 GMT",
"version": "v1"
},
{
"created": "Thu, 5 May 2011 17:11:32 GMT",
"version": "v2"
}
] | 2011-05-25 | [
[
"Aliev",
"T. M.",
""
],
[
"Azizi",
"K.",
""
],
[
"Savci",
"M.",
""
],
[
"Zamiralov",
"V. S.",
""
]
] | The heavy spin--3/2 baryon--heavy spin--1/2 baryon vertices with light vector mesons are studied within the light cone QCD sum rules method. These vertices are parametrized in terms of three coupling constants. These couplings are calculated for all possible transitions. It is shown that correlation functions for these transitions are described by only one invariant function for every Lorenz structure. The obtained relations between the correlation functions of the different transitions are structure independent while explicit expressions of invariant functions depend on the Lorenz structure. |
1003.3677 | Azar Mustafayev | John Ellis, Azar Mustafayev and Keith A. Olive | What if Supersymmetry Breaking Unifies beyond the GUT Scale? | 24 pages with 11 eps figures; references added, some figures
corrected, discussion extended and figure added; version to appear in EPJC | null | 10.1140/epjc/s10052-010-1373-8 | CERN-PH-TH/2010-065, UMN-TH-2840/10, FTPI-MINN-10/09 | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study models in which soft supersymmetry-breaking parameters of the MSSM
become universal at some unification scale, $M_{in}$, above the GUT scale,
$\mgut$. We assume that the scalar masses and gaugino masses have common
values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$. We use the
renormalization-group equations of the minimal supersymmetric SU(5) GUT to
evaluate their evolutions down to $\mgut$, studying their dependences on the
unknown parameters of the SU(5) superpotential. After displaying some generic
examples of the evolutions of the soft supersymmetry-breaking parameters, we
discuss the effects on physical sparticle masses in some specific examples. We
note, for example, that near-degeneracy between the lightest neutralino and the
lighter stau is progressively disfavoured as $M_{in}$ increases. This has the
consequence, as we show in $(m_{1/2}, m_0)$ planes for several different values
of $\tan \beta$, that the stau coannihilation region shrinks as $M_{in}$
increases, and we delineate the regions of the $(M_{in}, \tan \beta)$ plane
where it is absent altogether. Moreover, as $M_{in}$ increases, the focus-point
region recedes to larger values of $m_0$ for any fixed $\tan \beta$ and
$m_{1/2}$. We conclude that the regions of the $(m_{1/2}, m_0)$ plane that are
commonly favoured in phenomenological analyses tend to disappear at large
$M_{in}$.
| [
{
"created": "Thu, 18 Mar 2010 20:29:30 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Jun 2010 17:34:22 GMT",
"version": "v2"
}
] | 2015-05-18 | [
[
"Ellis",
"John",
""
],
[
"Mustafayev",
"Azar",
""
],
[
"Olive",
"Keith A.",
""
]
] | We study models in which soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, $M_{in}$, above the GUT scale, $\mgut$. We assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$. We use the renormalization-group equations of the minimal supersymmetric SU(5) GUT to evaluate their evolutions down to $\mgut$, studying their dependences on the unknown parameters of the SU(5) superpotential. After displaying some generic examples of the evolutions of the soft supersymmetry-breaking parameters, we discuss the effects on physical sparticle masses in some specific examples. We note, for example, that near-degeneracy between the lightest neutralino and the lighter stau is progressively disfavoured as $M_{in}$ increases. This has the consequence, as we show in $(m_{1/2}, m_0)$ planes for several different values of $\tan \beta$, that the stau coannihilation region shrinks as $M_{in}$ increases, and we delineate the regions of the $(M_{in}, \tan \beta)$ plane where it is absent altogether. Moreover, as $M_{in}$ increases, the focus-point region recedes to larger values of $m_0$ for any fixed $\tan \beta$ and $m_{1/2}$. We conclude that the regions of the $(m_{1/2}, m_0)$ plane that are commonly favoured in phenomenological analyses tend to disappear at large $M_{in}$. |
1807.10288 | Sacha Davidson | Sacha Davidson, Albert Saporta | Constraints on 2l2q operators from $\mu - e$ flavour-changing meson
decays | 11 pages, + 6 pages appendices; new discussion of how to update
bounds, version submitted to journal | Phys. Rev. D 99, 015032 (2019) | 10.1103/PhysRevD.99.015032 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study lepton flavour violating two- and three-body decays of pseudoscalar
mesons in Effective Field Theory (EFT). We give analytic formulae for the decay
rates in the presence of a complete basis of QED and QCD-invariant operators.
The constraints are obtained at the experimental scale, then translated to the
weak scale via one-loop RGEs. The large RG-mixing between tensor and
(pseudo)scalar operators weakens the constraints on scalar and pseudoscalar
operators at the weak scale.
| [
{
"created": "Thu, 26 Jul 2018 18:00:02 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Nov 2018 19:11:41 GMT",
"version": "v2"
}
] | 2019-01-30 | [
[
"Davidson",
"Sacha",
""
],
[
"Saporta",
"Albert",
""
]
] | We study lepton flavour violating two- and three-body decays of pseudoscalar mesons in Effective Field Theory (EFT). We give analytic formulae for the decay rates in the presence of a complete basis of QED and QCD-invariant operators. The constraints are obtained at the experimental scale, then translated to the weak scale via one-loop RGEs. The large RG-mixing between tensor and (pseudo)scalar operators weakens the constraints on scalar and pseudoscalar operators at the weak scale. |
hep-ph/9912281 | Tibor Torma | T. Torma (Univ. of Toronto) | A systematic analysis of new physics effects in spin correlations in q
qbar to t tbar | 16 pages RevTeX, 2 embedded figures | JHEP 0111 (2001) 055 | 10.1088/1126-6708/2001/11/055 | null | hep-ph | null | I show that there are eight new physics operators that contribute to top pair
production and subsequent decay in interference with the leading SM process at
the Tevatron and estimate their expected statistical inaccuracies. All fully
differential cross sections are calculated in the {6-particle} phase space. The
observation of angular correlations dramatically improves the accuracy of the
extraction.
| [
{
"created": "Thu, 9 Dec 1999 19:04:29 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Torma",
"T.",
"",
"Univ. of Toronto"
]
] | I show that there are eight new physics operators that contribute to top pair production and subsequent decay in interference with the leading SM process at the Tevatron and estimate their expected statistical inaccuracies. All fully differential cross sections are calculated in the {6-particle} phase space. The observation of angular correlations dramatically improves the accuracy of the extraction. |
hep-ph/0312230 | Nicholas Kersting | Nick Kersting and Yong-Liang Ma | Can a Nonsymmetric Metric mimic NCQFT in $e^+e^- \to \gamma \gamma$ ? | 15 pages, 3 figures. Expanded discussion of Seiberg-Witten map
included | Eur.Phys.J. C38 (2004) 379-388 | 10.1140/epjc/s2004-02043-8 | TUHEP-TH-03145 | hep-ph | null | In the nonsymmetric gravitational theory (NGT) the space-time metric
$g_{\mu\nu}$ departs from the flat-space Minkowski form $\eta_{\mu\nu}$ such
that it is no longer symmetric, $i.e.$ $g_{\mu\nu} \ne g_{\nu\mu}$. We find
that in the most conservative such scenario coupled to quantum field theory,
which we call Minimally Nonsymmetric Quantum Field Theory (MNQFT), there are
experimentally measurable consequences similar to those from noncommutative
quantum field theory (NCQFT). This can be expected from the Seiberg-Witten map
which has recently been interpreted as equating gauge theories on
noncommutative spacetimes with those in a field dependent gravitational
background. In particular, in scattering processes such as the pair
annihilation $e^+e^- \to \gamma\gamma$, both theories make the same striking
prediction that the azimuthal cross section oscillates in $\phi$. However the
predicted number of oscillations differs in the two theories: MNQFT predicts
between one and four, whereas NCQFT has no such restriction.
| [
{
"created": "Wed, 17 Dec 2003 02:17:09 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Mar 2004 16:30:08 GMT",
"version": "v2"
},
{
"created": "Mon, 24 Jan 2005 08:01:02 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Kersting",
"Nick",
""
],
[
"Ma",
"Yong-Liang",
""
]
] | In the nonsymmetric gravitational theory (NGT) the space-time metric $g_{\mu\nu}$ departs from the flat-space Minkowski form $\eta_{\mu\nu}$ such that it is no longer symmetric, $i.e.$ $g_{\mu\nu} \ne g_{\nu\mu}$. We find that in the most conservative such scenario coupled to quantum field theory, which we call Minimally Nonsymmetric Quantum Field Theory (MNQFT), there are experimentally measurable consequences similar to those from noncommutative quantum field theory (NCQFT). This can be expected from the Seiberg-Witten map which has recently been interpreted as equating gauge theories on noncommutative spacetimes with those in a field dependent gravitational background. In particular, in scattering processes such as the pair annihilation $e^+e^- \to \gamma\gamma$, both theories make the same striking prediction that the azimuthal cross section oscillates in $\phi$. However the predicted number of oscillations differs in the two theories: MNQFT predicts between one and four, whereas NCQFT has no such restriction. |
1905.08115 | Jean-Philippe Guillet | J. Ph. Guillet (1), E. Pilon (1), Y. Shimizu (2) and M. S. Zidi (3)
((1) LAPTH, France (2) KEK, Japan (3) LPTh, Alg\'erie) | Framework for a novel mixed analytical/numerical approach for the
computation of two-loop $N$-point Feynman diagrams | 24 pages, 8 figures, changes in the title, addition of a new section
on the decomposition of polytopes into simplexes, the appendix A has been
completed | Prog Theor Exp Phys (2020) | 10.1093/ptep/ptaa020 | LAPTH-029/19 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A framework to represent and compute two-loop $N$-point Feynman diagrams as
double-integrals is discussed. The integrands are 'generalised one-loop type"
multi-point functions multiplied by simple weighting factors. The final
integrations over these two variables are to be performed numerically, whereas
the ingredients involved in the integrands, in particular the "generalised
one-loop type" functions, are computed analytically. The idea is illustrated on
a few examples of scalar three- and four-point functions.
| [
{
"created": "Mon, 20 May 2019 13:55:21 GMT",
"version": "v1"
},
{
"created": "Thu, 27 Jun 2019 13:08:59 GMT",
"version": "v2"
},
{
"created": "Mon, 10 Feb 2020 14:15:08 GMT",
"version": "v3"
}
] | 2020-04-15 | [
[
"Guillet",
"J. Ph.",
"",
"LAPTH, France"
],
[
"Pilon",
"E.",
"",
"LAPTH, France"
],
[
"Shimizu",
"Y.",
"",
"KEK, Japan"
],
[
"Zidi",
"M. S.",
"",
"LPTh, Algérie"
]
] | A framework to represent and compute two-loop $N$-point Feynman diagrams as double-integrals is discussed. The integrands are 'generalised one-loop type" multi-point functions multiplied by simple weighting factors. The final integrations over these two variables are to be performed numerically, whereas the ingredients involved in the integrands, in particular the "generalised one-loop type" functions, are computed analytically. The idea is illustrated on a few examples of scalar three- and four-point functions. |
hep-ph/0007236 | Salgado Carlos | A. Capella and C.A. Salgado | Hyperon Enhancement in the Dual Parton Model | 6 pages, 2 eps-figures | NewJ.Phys.2:30,2000 | 10.1088/1367-2630/2/1/330 | LPT Orsay 00-66 | hep-ph | null | We review the two sources of hyperon enhancement in the dual parton model:
strings originating from diquark-antidiquark pairs in the nucleon sea and net
baryons containing two or three sea quarks with a yield controlled by the
observed stopping. We show that adding final state interactions (including
strangeness exchange reactions as well as the inverse reactions required by
detailed balance) with a single averaged cross-section $\sigma=0.2$ mb, we can
explain the observed hyperon enhancement in PbPb collisions at CERN SPS.
| [
{
"created": "Fri, 21 Jul 2000 09:50:49 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Capella",
"A.",
""
],
[
"Salgado",
"C. A.",
""
]
] | We review the two sources of hyperon enhancement in the dual parton model: strings originating from diquark-antidiquark pairs in the nucleon sea and net baryons containing two or three sea quarks with a yield controlled by the observed stopping. We show that adding final state interactions (including strangeness exchange reactions as well as the inverse reactions required by detailed balance) with a single averaged cross-section $\sigma=0.2$ mb, we can explain the observed hyperon enhancement in PbPb collisions at CERN SPS. |
2110.15854 | Arnab Chaudhuri | Arnab Chaudhuri and Maxim Yu. Khlopov | Dark matter dilution scenarios in the early universe | 12 pages, 2 figures. arXiv admin note: text overlap with
arXiv:1711.01801, arXiv:2001.11219 | null | 10.1142/S0218271821400083 | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | When the vacuum like energy of the Higgs potential within the standard model
undergoes electroweak phase transition, an influx of entropy into the
primordial plasma can lead to a significant dilution of frozen out dark matter
density that was already present before the onset of the phase transition. The
same effect can take place, if the early Universe was dominated by primordial
black holes of small mass, evaporating before the period of Big Bang
Nucleosynthesis. In this paper we calculate the dilution factor for the above
mentioned scenarios.
| [
{
"created": "Fri, 29 Oct 2021 15:27:21 GMT",
"version": "v1"
}
] | 2022-02-16 | [
[
"Chaudhuri",
"Arnab",
""
],
[
"Khlopov",
"Maxim Yu.",
""
]
] | When the vacuum like energy of the Higgs potential within the standard model undergoes electroweak phase transition, an influx of entropy into the primordial plasma can lead to a significant dilution of frozen out dark matter density that was already present before the onset of the phase transition. The same effect can take place, if the early Universe was dominated by primordial black holes of small mass, evaporating before the period of Big Bang Nucleosynthesis. In this paper we calculate the dilution factor for the above mentioned scenarios. |
hep-ph/9510462 | Sergey Goloskokov | S.V.Goloskokov (BLTP JINR, Dubna, Russia) | Study of Single-Spin Asymmetry in Diffractive High- $p_t$-Jet Production | 10 pages, Latex, 3 PS figures in one uuencode compressed file, talk
at 2nd Meeting on Possible Measurements of Singly Polarized pp and pn
Collisions at HERA (DESY-IfH Zeuthen, Aug 31- Sep 2, 1995) | null | null | null | hep-ph | null | It is shown that the transverse single spin asymmetry in polarized
diffractive $Q \bar Q$ production depends strongly on the spin structure of the
pomeron coupling. It is concluded that the spin properties of quark-pomeron and
proton-pomeron vertices can be studied in future HERA-N experiments.
| [
{
"created": "Tue, 31 Oct 1995 20:17:05 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Goloskokov",
"S. V.",
"",
"BLTP JINR, Dubna, Russia"
]
] | It is shown that the transverse single spin asymmetry in polarized diffractive $Q \bar Q$ production depends strongly on the spin structure of the pomeron coupling. It is concluded that the spin properties of quark-pomeron and proton-pomeron vertices can be studied in future HERA-N experiments. |
2104.09772 | Tanmay Kumar Poddar | Tanmay Kumar Poddar | Constraints on axionic fuzzy dark matter from light bending and Shapiro
time delay | 22 pages, 6 figures, 1 table, comments are welcome | JCAP09(2021)041 | 10.1088/1475-7516/2021/09/041 | null | hep-ph astro-ph.CO gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Ultralight axion like particles (ALPs) of mass $m_a\in
(10^{-21}\rm{eV}-10^{-22}\rm{eV})$ with axion decay constant $f_a\sim
10^{17}\rm{GeV}$ can be candidates for fuzzy dark matter (FDM). If celestial
bodies like Earth and Sun are immersed in a low mass axionic FDM potential and
if the ALPs have coupling with nucleons then the coherent oscillation of the
axionic field results a long range axion hair outside of the celestial bodies.
The range of the axion mediated Yukawa type fifth force is determined by the
distance between the Earth and the Sun which fixes the upper bound of the mass
of axion as $m_a\lesssim10^{-18}\rm{eV}$. The long range axionic Yukawa
potential between the Earth and Sun changes the gravitational potential between
them and contribute to the light bending and the Shapiro time delay. From the
observational uncertainties of those experiments, we put an upper bound on the
axion decay constant as $f_a\lesssim 9.85\times 10^{6}\rm{GeV}$, which is the
stronger bound obtained from Shapiro time delay. This implies if ALPs are FDM,
then they do not couple to nucleons.
| [
{
"created": "Tue, 20 Apr 2021 06:00:43 GMT",
"version": "v1"
}
] | 2021-10-08 | [
[
"Poddar",
"Tanmay Kumar",
""
]
] | Ultralight axion like particles (ALPs) of mass $m_a\in (10^{-21}\rm{eV}-10^{-22}\rm{eV})$ with axion decay constant $f_a\sim 10^{17}\rm{GeV}$ can be candidates for fuzzy dark matter (FDM). If celestial bodies like Earth and Sun are immersed in a low mass axionic FDM potential and if the ALPs have coupling with nucleons then the coherent oscillation of the axionic field results a long range axion hair outside of the celestial bodies. The range of the axion mediated Yukawa type fifth force is determined by the distance between the Earth and the Sun which fixes the upper bound of the mass of axion as $m_a\lesssim10^{-18}\rm{eV}$. The long range axionic Yukawa potential between the Earth and Sun changes the gravitational potential between them and contribute to the light bending and the Shapiro time delay. From the observational uncertainties of those experiments, we put an upper bound on the axion decay constant as $f_a\lesssim 9.85\times 10^{6}\rm{GeV}$, which is the stronger bound obtained from Shapiro time delay. This implies if ALPs are FDM, then they do not couple to nucleons. |
1706.08985 | Alessandro Davoli | Alessandro Davoli, Andrea De Simone, Thomas Jacques, Ver\'onica Sanz | Displaced Vertices from Pseudo-Dirac Dark Matter | 23 pages, 4 figures, 2 tables | JHEP 1711 (2017) 025 | 10.1007/JHEP11(2017)025 | SISSA 29/2017/FISI | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Displaced vertices are relatively unusual signatures for dark matter searches
at the LHC. We revisit the model of pseudo-Dirac dark matter (pDDM), which can
accommodate the correct relic density, evade direct detection constraints, and
generically provide observable collider signatures in the form of displaced
vertices. We use this model as a benchmark to illustrate the general techniques
involved in the analysis, the complementarity between monojet and displaced
vertex searches, and provide a comprehensive study of the current bounds and
prospective reach.
| [
{
"created": "Tue, 27 Jun 2017 18:02:50 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Nov 2017 12:49:42 GMT",
"version": "v2"
},
{
"created": "Thu, 21 Jun 2018 19:09:26 GMT",
"version": "v3"
}
] | 2018-06-25 | [
[
"Davoli",
"Alessandro",
""
],
[
"De Simone",
"Andrea",
""
],
[
"Jacques",
"Thomas",
""
],
[
"Sanz",
"Verónica",
""
]
] | Displaced vertices are relatively unusual signatures for dark matter searches at the LHC. We revisit the model of pseudo-Dirac dark matter (pDDM), which can accommodate the correct relic density, evade direct detection constraints, and generically provide observable collider signatures in the form of displaced vertices. We use this model as a benchmark to illustrate the general techniques involved in the analysis, the complementarity between monojet and displaced vertex searches, and provide a comprehensive study of the current bounds and prospective reach. |
1711.06717 | Johannes Bl\"umlein | J. Ablinger, J. Bl\"umlein, A. De Freitas, C. Schneider, and K.
Sch\"onwald | The two-mass contribution to the three-loop pure singlet operator matrix
element | 28 papges Latex, 3 figures | null | 10.1016/j.nuclphysb.2017.12.018 | DESY 17--195, DO--TH 17/32 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the two-mass QCD contributions to the pure singlet operator matrix
element at three loop order in x-space. These terms are relevant for
calculating the structure function $F_2(x,Q^2)$ at $O(\alpha_s^3)$ as well as
for the matching relations in the variable flavor number scheme and the heavy
quark distribution functions at the same order. The result for the operator
matrix element is given in terms of generalized iterated integrals that include
square root letters in the alphabet, depending also on the mass ratio through
the main argument. Numerical results are presented.
| [
{
"created": "Fri, 17 Nov 2017 20:27:30 GMT",
"version": "v1"
}
] | 2018-02-01 | [
[
"Ablinger",
"J.",
""
],
[
"Blümlein",
"J.",
""
],
[
"De Freitas",
"A.",
""
],
[
"Schneider",
"C.",
""
],
[
"Schönwald",
"K.",
""
]
] | We present the two-mass QCD contributions to the pure singlet operator matrix element at three loop order in x-space. These terms are relevant for calculating the structure function $F_2(x,Q^2)$ at $O(\alpha_s^3)$ as well as for the matching relations in the variable flavor number scheme and the heavy quark distribution functions at the same order. The result for the operator matrix element is given in terms of generalized iterated integrals that include square root letters in the alphabet, depending also on the mass ratio through the main argument. Numerical results are presented. |
1102.5028 | Daniel Almeida Fagundes | D.A. Fagundes, M.J. Menon, G.L.P. Silva | Model-independent data reductions of elastic proton-proton scattering | 14 pages, 7 figures, typos corrected, published version | Eur.Phys.J.C71:1637,2011 | 10.1140/epjc/s10052-011-1637-y | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | New developments in empirical analyses of the proton-proton differential
cross section data at high energies are reported. Making use of an
unconstrained model-independent parametrization for the scattering amplitude
and two different fit procedures, all the experimental data in the
center-of-mass energy interval 19.4 - 62.5 GeV are quite well described
(optical point and data above the region of Coulomb-nuclear interference). The
contributions from the real and imaginary parts of the amplitude beyond the
forward direction are discussed and compared with the results from previous
analyses and phenomenological models. Extracted overlap functions (impact
parameter space) are outlined and a critical discussion on model-independent
analyses and results are also presented.
| [
{
"created": "Thu, 24 Feb 2011 16:31:42 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Feb 2011 13:43:41 GMT",
"version": "v2"
},
{
"created": "Tue, 19 Apr 2011 14:38:37 GMT",
"version": "v3"
},
{
"created": "Thu, 26 May 2011 15:30:56 GMT",
"version": "v4"
}
] | 2011-05-27 | [
[
"Fagundes",
"D. A.",
""
],
[
"Menon",
"M. J.",
""
],
[
"Silva",
"G. L. P.",
""
]
] | New developments in empirical analyses of the proton-proton differential cross section data at high energies are reported. Making use of an unconstrained model-independent parametrization for the scattering amplitude and two different fit procedures, all the experimental data in the center-of-mass energy interval 19.4 - 62.5 GeV are quite well described (optical point and data above the region of Coulomb-nuclear interference). The contributions from the real and imaginary parts of the amplitude beyond the forward direction are discussed and compared with the results from previous analyses and phenomenological models. Extracted overlap functions (impact parameter space) are outlined and a critical discussion on model-independent analyses and results are also presented. |
2007.13691 | Oleksandr Sobol Dr. | A. Boyarsky, V. Cheianov, O. Ruchayskiy, and O. Sobol | Evolution of the Primordial Axial Charge across Cosmic Times | 7 pages, 3 figures + Supplementary Material (3 pages) | Phys. Rev. Lett. 126, 021801 (2021) | 10.1103/PhysRevLett.126.021801 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate collisional decay of the axial charge in an electron-photon
plasma at temperatures 10 MeV - 100 GeV. We demonstrate that the decay rate of
the axial charge is first order in the fine-structure constant $\Gamma_{\rm
flip}\propto \alpha m_{e}^{2}/T$ and thus orders of magnitude greater than the
naive estimate which has been in use for decades. This counterintuitive result
arises through infrared divergences regularized at high temperature by
environmental effects. The decay of axial charge plays an important role in the
problems of leptogenesis and cosmic magnetogenesis.
| [
{
"created": "Mon, 27 Jul 2020 17:08:17 GMT",
"version": "v1"
},
{
"created": "Sat, 1 Aug 2020 22:06:25 GMT",
"version": "v2"
},
{
"created": "Tue, 12 Jan 2021 18:09:25 GMT",
"version": "v3"
}
] | 2021-01-20 | [
[
"Boyarsky",
"A.",
""
],
[
"Cheianov",
"V.",
""
],
[
"Ruchayskiy",
"O.",
""
],
[
"Sobol",
"O.",
""
]
] | We investigate collisional decay of the axial charge in an electron-photon plasma at temperatures 10 MeV - 100 GeV. We demonstrate that the decay rate of the axial charge is first order in the fine-structure constant $\Gamma_{\rm flip}\propto \alpha m_{e}^{2}/T$ and thus orders of magnitude greater than the naive estimate which has been in use for decades. This counterintuitive result arises through infrared divergences regularized at high temperature by environmental effects. The decay of axial charge plays an important role in the problems of leptogenesis and cosmic magnetogenesis. |
hep-ph/9801382 | null | N. G. Marchuk | A model of the composite structure of quarks and leptons with SU(4)
gauge symmetry | Plain TeX, 8 pages | null | null | Steklov Mathematical Institute MATH-18.1.98 | hep-ph | null | A model in which quarks and leptons consist of three "more elementary"
particles of spin 1/2 is proposed. A gauge field theory with SU(4) symmetry
that corresponds to this model predicts the existence of two new bosons.
| [
{
"created": "Wed, 21 Jan 1998 19:34:41 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Marchuk",
"N. G.",
""
]
] | A model in which quarks and leptons consist of three "more elementary" particles of spin 1/2 is proposed. A gauge field theory with SU(4) symmetry that corresponds to this model predicts the existence of two new bosons. |
1005.3116 | Alexander Merle | Manfred Lindner, Alexander Merle, Viviana Niro | Enhancing Dark Matter Annihilation into Neutrinos | 33 pages, 2 figures | Phys.Rev.D82:123529,2010 | 10.1103/PhysRevD.82.123529 | null | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a detailed and quasi model-independent analysis of direct
annihilation of Dark Matter into neutrinos. Considering different cases for
scalar and fermionic Dark Matter, we identify several settings in which this
annihilation is enhanced, contrary to some statements in the literature. They
key point is that several restrictions of, e.g., a supersymmetric framework do
not hold in general. The mass generation mechanism of the neutrinos plays an
important role, too. We illustrate our considerations by two examples that are
not (as usually) suppressed by the smallness of the neutrino mass, for which we
also present a numerical analysis. Our results can be easily used as guidelines
for model building.
| [
{
"created": "Tue, 18 May 2010 07:45:31 GMT",
"version": "v1"
}
] | 2011-01-20 | [
[
"Lindner",
"Manfred",
""
],
[
"Merle",
"Alexander",
""
],
[
"Niro",
"Viviana",
""
]
] | We perform a detailed and quasi model-independent analysis of direct annihilation of Dark Matter into neutrinos. Considering different cases for scalar and fermionic Dark Matter, we identify several settings in which this annihilation is enhanced, contrary to some statements in the literature. They key point is that several restrictions of, e.g., a supersymmetric framework do not hold in general. The mass generation mechanism of the neutrinos plays an important role, too. We illustrate our considerations by two examples that are not (as usually) suppressed by the smallness of the neutrino mass, for which we also present a numerical analysis. Our results can be easily used as guidelines for model building. |
hep-ph/0203201 | Taekoon Lee | Carlos Contreras, Gorazd Cvetic, Kwang Sik Jeong, and Taekoon Lee | Extraction of alpha_s from the Gross--Llewellyn Smith sum rule using
Borel resummation | 22 pages, version to appear in Phys. Rev. D | Phys.Rev. D66 (2002) 054006 | 10.1103/PhysRevD.66.054006 | null | hep-ph hep-ex | null | Using the CCFR data for the Gross--Llewellyn Smith (GLS) sum rule, we extract
the strong coupling constant via Borel resummation of the perturbative QCD
calculation. The method incorporates the correct nature of the first infrared
renormalon singularity, and employs a conformal mapping to improve the
convergence of the QCD perturbation expansion. The important twist-four
contribution is calculated from resummation of the perturbation theory, which
is based on the ansatz that the higher--twist contribution has a cut
singularity only along the positive real axis on the complex coupling plane.
Thus obtained, the strong coupling constant corresponding to the central GLS
experimental value is in good agreement with the world average.
| [
{
"created": "Thu, 21 Mar 2002 01:51:41 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Jul 2002 09:12:10 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Contreras",
"Carlos",
""
],
[
"Cvetic",
"Gorazd",
""
],
[
"Jeong",
"Kwang Sik",
""
],
[
"Lee",
"Taekoon",
""
]
] | Using the CCFR data for the Gross--Llewellyn Smith (GLS) sum rule, we extract the strong coupling constant via Borel resummation of the perturbative QCD calculation. The method incorporates the correct nature of the first infrared renormalon singularity, and employs a conformal mapping to improve the convergence of the QCD perturbation expansion. The important twist-four contribution is calculated from resummation of the perturbation theory, which is based on the ansatz that the higher--twist contribution has a cut singularity only along the positive real axis on the complex coupling plane. Thus obtained, the strong coupling constant corresponding to the central GLS experimental value is in good agreement with the world average. |
hep-ph/9408250 | Debajyoti Choudhury | Debajyoti Choudhury | Leptoquark Search at $e^+ e^-$ Colliders | 12 pages (LaTeX), 4 figures (uuencoded postscript file submitted
through `figures option'), MPI preprint MPI-PhT/94-50 | Phys.Lett. B346 (1995) 291-296 | 10.1016/0370-2693(95)00018-G | null | hep-ph | null | We investigate the possibility of detecting a scalar leptoquark, coupling to
the electron and the top, at a linear collider. For coupling strength equalling
the weak coupling constant, the present mass bounds are of the order of 300
GeV. We demonstrate that at the NLC, one could detect such particles if their
mass were less than a few TeV's.
| [
{
"created": "Mon, 8 Aug 1994 13:37:08 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Choudhury",
"Debajyoti",
""
]
] | We investigate the possibility of detecting a scalar leptoquark, coupling to the electron and the top, at a linear collider. For coupling strength equalling the weak coupling constant, the present mass bounds are of the order of 300 GeV. We demonstrate that at the NLC, one could detect such particles if their mass were less than a few TeV's. |
2207.08576 | Meril Reboud | M\'eril Reboud | EOS -- A Software for Flavor Physics Phenomenology | 9 pages, 4 figures | PoS Volume 409 - Computational Tools for High Energy Physics and
Cosmology (CompTools2021) | 10.22323/1.409.0012 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I present EOS, an open-source software dedicated to a variety of tasks in the
processing of flavor physics observables. EOS is written in C++ and offers both
a C++ and a Python interface. It is developed for three main tasks, the
production of theoretical predictions for flavor physics observables; the
inference of theoretical parameters from an extensible database of likelihoods;
and the production of Monte Carlo samples of flavor processes for sensitivity
studies.
| [
{
"created": "Mon, 18 Jul 2022 13:00:16 GMT",
"version": "v1"
}
] | 2022-12-19 | [
[
"Reboud",
"Méril",
""
]
] | I present EOS, an open-source software dedicated to a variety of tasks in the processing of flavor physics observables. EOS is written in C++ and offers both a C++ and a Python interface. It is developed for three main tasks, the production of theoretical predictions for flavor physics observables; the inference of theoretical parameters from an extensible database of likelihoods; and the production of Monte Carlo samples of flavor processes for sensitivity studies. |
hep-ph/9609442 | Rachel Jeannerot | R. Jeannerot (DAMTP, Cambridge, UK) | New mechanism for leptogenesis | 9 pages, uses Revtex, includes one figure | Phys.Rev.Lett. 77 (1996) 3292-3295 | 10.1103/PhysRevLett.77.3292 | DAMTP-96-67 | hep-ph | null | Unified theories containing a $U(1)_{B-L}$ gauge symmetry predict heavy
Majorana right-handed neutrinos. In such theories, cosmic strings may form at
the $B-L$ breaking scale. If the Higgs field forming the strings is also the
Higgs field which gives mass to the right-handed neutrinos, there are
right-handed neutrinos trapped as transverse zero modes in the core of the
strings. When cosmic string loops decay, they release these neutrinos. This is
an out-of-equilibrium process. The released neutrinos acquire heavy Majorana
mass and decay into massless leptons and electroweak Higgs particles to produce
a lepton asymmetry, which is converted into a baryon asymmetry via sphaleron
transitions.
| [
{
"created": "Mon, 23 Sep 1996 16:07:28 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Jeannerot",
"R.",
"",
"DAMTP, Cambridge, UK"
]
] | Unified theories containing a $U(1)_{B-L}$ gauge symmetry predict heavy Majorana right-handed neutrinos. In such theories, cosmic strings may form at the $B-L$ breaking scale. If the Higgs field forming the strings is also the Higgs field which gives mass to the right-handed neutrinos, there are right-handed neutrinos trapped as transverse zero modes in the core of the strings. When cosmic string loops decay, they release these neutrinos. This is an out-of-equilibrium process. The released neutrinos acquire heavy Majorana mass and decay into massless leptons and electroweak Higgs particles to produce a lepton asymmetry, which is converted into a baryon asymmetry via sphaleron transitions. |
2109.07336 | Manuel Masip | Antonio J. Cuesta, Mario E. G\'omez, Jos\'e I. Illana, Manuel Masip | Cosmology of an Axion-Like Majoron | 23 pages, version to appear in JCAP | null | 10.1088/1475-7516/2022/04/009 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a singlet majoron model that defines an inverse seesaw mechanism
in the $\nu$ sector. The majoron $\phi$ has a mass $m_\phi\approx 0.5$ eV and a
coupling to the $\tau$ lepton similar to the one to neutrinos. In the early
universe it is initially in thermal equilibrium, then it decouples at $T\approx
500$ GeV and contributes with just $\Delta N_{\rm eff}=0.026$ during BBN. At
$T=26$ keV (final stages of BBN) a primordial magnetic field induces resonant
$\gamma \leftrightarrow \phi$ oscillations that transfer 6% of the photon
energy into majorons, implying $\Delta N_{\rm eff}=0.55$ and a 4.7% increase in
the baryon to photon ratio. At $T\approx m_\phi$ the majoron enters in thermal
contact with the heaviest neutrino and it finally decays into $\nu \bar \nu$
pairs near recombination, setting $\Delta N_{\rm eff}=0.85$. The boost in the
expansion rate at later times may relax the Hubble tension (we obtain
$H_0=(71.4\pm 0.5)$ km/s/Mpc), while the processes $ \nu\bar \nu
\leftrightarrow \phi$ suppress the free streaming of these particles and make
the model consistent with large scale structure observations. Its lifetime and
the fact that it decays into neutrinos instead of photons lets this axion-like
majoron avoid the strong bounds that affect other axion-like particles of
similar mass and coupling to photons.
| [
{
"created": "Wed, 15 Sep 2021 14:44:26 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Sep 2021 08:23:30 GMT",
"version": "v2"
},
{
"created": "Fri, 8 Oct 2021 13:47:36 GMT",
"version": "v3"
},
{
"created": "Tue, 5 Apr 2022 13:02:09 GMT",
"version": "v4"
}
] | 2022-04-13 | [
[
"Cuesta",
"Antonio J.",
""
],
[
"Gómez",
"Mario E.",
""
],
[
"Illana",
"José I.",
""
],
[
"Masip",
"Manuel",
""
]
] | We propose a singlet majoron model that defines an inverse seesaw mechanism in the $\nu$ sector. The majoron $\phi$ has a mass $m_\phi\approx 0.5$ eV and a coupling to the $\tau$ lepton similar to the one to neutrinos. In the early universe it is initially in thermal equilibrium, then it decouples at $T\approx 500$ GeV and contributes with just $\Delta N_{\rm eff}=0.026$ during BBN. At $T=26$ keV (final stages of BBN) a primordial magnetic field induces resonant $\gamma \leftrightarrow \phi$ oscillations that transfer 6% of the photon energy into majorons, implying $\Delta N_{\rm eff}=0.55$ and a 4.7% increase in the baryon to photon ratio. At $T\approx m_\phi$ the majoron enters in thermal contact with the heaviest neutrino and it finally decays into $\nu \bar \nu$ pairs near recombination, setting $\Delta N_{\rm eff}=0.85$. The boost in the expansion rate at later times may relax the Hubble tension (we obtain $H_0=(71.4\pm 0.5)$ km/s/Mpc), while the processes $ \nu\bar \nu \leftrightarrow \phi$ suppress the free streaming of these particles and make the model consistent with large scale structure observations. Its lifetime and the fact that it decays into neutrinos instead of photons lets this axion-like majoron avoid the strong bounds that affect other axion-like particles of similar mass and coupling to photons. |
hep-ph/0511086 | Farida Iddir | F. Iddir and L. Semlala | 1^{-+}\pi_{1}(1400) cannot be hybrid meson | 4 pages | null | null | null | hep-ph | null | We expose arguments concerning the \pi_{1}(1400) observed decaying into
\eta\pi and claimed to be an exotic meson. We conclude that this object cannot
be a qqbar-g hybrid meson.
| [
{
"created": "Tue, 8 Nov 2005 08:13:37 GMT",
"version": "v1"
},
{
"created": "Sat, 12 Nov 2005 09:09:13 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Iddir",
"F.",
""
],
[
"Semlala",
"L.",
""
]
] | We expose arguments concerning the \pi_{1}(1400) observed decaying into \eta\pi and claimed to be an exotic meson. We conclude that this object cannot be a qqbar-g hybrid meson. |
hep-ph/9804215 | Andrzej Czarnecki | Andrzej Czarnecki and Kirill Melnikov | Two-loop QCD corrections to semileptonic b decays at an intermediate
recoil | 8 pages, revtex | Phys.Rev.D59:014036,1999 | 10.1103/PhysRevD.59.014036 | BNL-HET-98/12, TTP98-14 | hep-ph | null | We present complete O(alpha_s^2) corrections to the decay b-->c+l+nu at the
point where the invariant mass of the leptons sqrt{q^2} equals the c quark
mass. We use this result, together with previously obtained corrections at the
ends of the q^2 spectrum, to estimate the total width of the semileptonic b-->c
decay with O(alpha_s^2) accuracy, essential for the |V_{cb}| determination.
| [
{
"created": "Thu, 2 Apr 1998 14:26:43 GMT",
"version": "v1"
}
] | 2011-01-25 | [
[
"Czarnecki",
"Andrzej",
""
],
[
"Melnikov",
"Kirill",
""
]
] | We present complete O(alpha_s^2) corrections to the decay b-->c+l+nu at the point where the invariant mass of the leptons sqrt{q^2} equals the c quark mass. We use this result, together with previously obtained corrections at the ends of the q^2 spectrum, to estimate the total width of the semileptonic b-->c decay with O(alpha_s^2) accuracy, essential for the |V_{cb}| determination. |
0905.3471 | Xiang Liu | Xiang Liu | Towards the decays of $\bar{N}_X(1625)$ in the molecular picture | 5 pages, 6 figures, 2 tables. Contribution to the Workshop on the
Physics of Excited Nucleon-NSTAR2009, Beijing April 19-22, 2009 | Chin. Phys. C33 (2009) 1307-1311 | 10.1088/1674-1137/33/12/043 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk, we firstly overview the experimental status of
$\bar{N}_X(1625)$, which is an enhancement structure observed in
$K^{-}\bar{\Lambda}$ invariant mass spectrum of $J/\psi\to pK^{-}\bar{\Lambda}$
process. Then we present the result of the decay of $\bar{N}_X(1625)$ under the
two molecular assumptions, i.e. S-wave $\bar\Lambda K^-$ and S-wave
$\bar{\Sigma}^0K^-$ molecular states. Several experimental suggestions for
$\bar{N}_X(1625)$ are proposed.
| [
{
"created": "Thu, 21 May 2009 11:21:35 GMT",
"version": "v1"
}
] | 2015-05-13 | [
[
"Liu",
"Xiang",
""
]
] | In this talk, we firstly overview the experimental status of $\bar{N}_X(1625)$, which is an enhancement structure observed in $K^{-}\bar{\Lambda}$ invariant mass spectrum of $J/\psi\to pK^{-}\bar{\Lambda}$ process. Then we present the result of the decay of $\bar{N}_X(1625)$ under the two molecular assumptions, i.e. S-wave $\bar\Lambda K^-$ and S-wave $\bar{\Sigma}^0K^-$ molecular states. Several experimental suggestions for $\bar{N}_X(1625)$ are proposed. |
hep-ph/9609521 | Mike Seymour | Stefano Catani (Firenze), Michael H. Seymour (CERN) | NLO QCD calculations in DIS at HERA based on the dipole formalism | 5 pages, 2 figures. Presented at the Workshop on Future Physics at
HERA, DESY, Hamburg, Germany. This paper can also be obtained from
http://surya11.cern.ch/users/seymour/pubs/hera.ps.Z | null | null | CERN-TH/96-240 | hep-ph | null | We briefly describe a new general algorithm for carrying out QCD calculations
to next-to-leading order in perturbation theory. The algorithm can be used for
computing arbitrary jet cross sections in arbitrary processes and can be
straightforwardly implemented in general-purpose Monte Carlo programs. We show
numerical results for the specific case of jet cross sections in deep inelastic
scattering at HERA energies.
| [
{
"created": "Mon, 30 Sep 1996 14:35:22 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Catani",
"Stefano",
"",
"Firenze"
],
[
"Seymour",
"Michael H.",
"",
"CERN"
]
] | We briefly describe a new general algorithm for carrying out QCD calculations to next-to-leading order in perturbation theory. The algorithm can be used for computing arbitrary jet cross sections in arbitrary processes and can be straightforwardly implemented in general-purpose Monte Carlo programs. We show numerical results for the specific case of jet cross sections in deep inelastic scattering at HERA energies. |
hep-ph/9903264 | Stephen J. Puglia | M.J. Ramsey-Musolf | Low-Energy Parity-Violation and New Physics | 37 pages, 2 figures. Omissions to Tables I and V corrected along with
some minor typographical errors. To appear in Phys. Rev. C | Phys.Rev. C60 (1999) 015501 | 10.1103/PhysRevC.60.015501 | DOE/ER/40561-49 | hep-ph | null | The new physics sensitivity of a variety of low-energy parity-violating (PV)
observables is analyzed. A comparison is made between atomic PV for a single
isotope, atomic PV using isotope ratios, and PV electron-hadron and
electron-electron scattering. The complementarity among these observables, as
well as with high-energy processes, is emphasized. Theoretical uncertainties
entering the interpretation of low-energy measurements are discussed.
| [
{
"created": "Fri, 5 Mar 1999 00:47:00 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Apr 1999 16:11:40 GMT",
"version": "v2"
},
{
"created": "Tue, 20 Apr 1999 20:18:30 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Ramsey-Musolf",
"M. J.",
""
]
] | The new physics sensitivity of a variety of low-energy parity-violating (PV) observables is analyzed. A comparison is made between atomic PV for a single isotope, atomic PV using isotope ratios, and PV electron-hadron and electron-electron scattering. The complementarity among these observables, as well as with high-energy processes, is emphasized. Theoretical uncertainties entering the interpretation of low-energy measurements are discussed. |
1508.07809 | Elmar Biernat P | Elmar P. Biernat, Franz Gross, M. T. Pe\~na, Alfred Stadler | Charge-conjugation symmetric complete impulse approximation for the pion
electromagnetic form factor in the Covariant Spectator Theory | 14 pages, 6 figures; some typos corrected; version published in Phys.
Rev. D | Phys. Rev. D92 (2015), 076011 | 10.1103/PhysRevD.92.076011 | CFTP/15-009, JLAB-THY-15-2125 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The pion form factor is calculated in the framework of the charge-conjugation
invariant Covariant Spectator Theory. This formalism is established in
Minkowski space and the calculation is set up in momentum space. In a previous
calculation we included only the leading pole coming from the spectator quark
(referred to as the relativistic impulse approximation). In this paper we also
include the contributions from the poles of the quark which interacts with the
photon and average over all poles in both the upper and lower half planes in
order to preserve charge conjugation invariance (referred to as the
$C$-symmetric complete impulse approximation). We find that for small pion mass
these contributions are significant at all values of the four-momentum transfer
$Q^2$ but, surprisingly, do not alter the shape obtained from the spectator
poles alone.
| [
{
"created": "Mon, 31 Aug 2015 13:06:02 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Oct 2015 15:22:45 GMT",
"version": "v2"
}
] | 2015-10-27 | [
[
"Biernat",
"Elmar P.",
""
],
[
"Gross",
"Franz",
""
],
[
"Peña",
"M. T.",
""
],
[
"Stadler",
"Alfred",
""
]
] | The pion form factor is calculated in the framework of the charge-conjugation invariant Covariant Spectator Theory. This formalism is established in Minkowski space and the calculation is set up in momentum space. In a previous calculation we included only the leading pole coming from the spectator quark (referred to as the relativistic impulse approximation). In this paper we also include the contributions from the poles of the quark which interacts with the photon and average over all poles in both the upper and lower half planes in order to preserve charge conjugation invariance (referred to as the $C$-symmetric complete impulse approximation). We find that for small pion mass these contributions are significant at all values of the four-momentum transfer $Q^2$ but, surprisingly, do not alter the shape obtained from the spectator poles alone. |
2112.10888 | Vicente Pleitez | V. Pleitez | Challenges for the 3-3-1 models | 58 pages; New references added | null | null | null | hep-ph hep-ex | http://creativecommons.org/publicdomain/zero/1.0/ | The so-called 3-3-1 models have been widely studied in the literature.
However, in almost all cases, as with other models, just simplified versions
have been considered. On the other hand, the LHC has not neither confirmed nor
rejected any model. In this paper we discuss some aspects of the 3-3-1 models
that must be investigated, or be re-analyzed, firstly theoretically and,
eventually, experimentally. Some of these issues are independent of the
representation content of the particular model, that is, they are independent
of the value of the $\beta$ parameter. However, others strongly depend on the
particular model considered.
| [
{
"created": "Mon, 20 Dec 2021 22:28:28 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Jan 2022 20:59:04 GMT",
"version": "v2"
},
{
"created": "Sun, 3 Jul 2022 18:08:08 GMT",
"version": "v3"
}
] | 2022-07-05 | [
[
"Pleitez",
"V.",
""
]
] | The so-called 3-3-1 models have been widely studied in the literature. However, in almost all cases, as with other models, just simplified versions have been considered. On the other hand, the LHC has not neither confirmed nor rejected any model. In this paper we discuss some aspects of the 3-3-1 models that must be investigated, or be re-analyzed, firstly theoretically and, eventually, experimentally. Some of these issues are independent of the representation content of the particular model, that is, they are independent of the value of the $\beta$ parameter. However, others strongly depend on the particular model considered. |
hep-ph/9408346 | Harold W. Fearing | H. W. Fearing and S. Scherer | Extension of the Chiral Perturbation Theory Meson Lagrangian to Order
$P^6$ | 59 pages in LaTex, using RevTex macro, TRIUMF preprint TRI-PP-94-68 | Phys.Rev. D53 (1996) 315-348 | 10.1103/PhysRevD.53.315 | null | hep-ph hep-th nucl-th | null | We have derived the most general chirally invariant Lagrangian ${\cal L}_6$
for the meson sector at order $p^6$. The result provides an extension of the
standard Gasser-Leutwyler Lagrangian ${\cal L}_4$ to one higher order,
including as well all the odd intrinsic parity terms in the Lagrangian. The
most difficult part of the derivation was developing a systematic strategy so
as to get all of the independent terms and eliminate the redundant ones in an
efficient way. The 'equation of motion' terms, which are redundant in the sense
that they can be transformed away via field transformations, are separated out
explicitly. The resulting Lagrangian has been separated into groupings of terms
contributing to increasingly more complicated processes, so that one does not
have to deal with the full result when calculating $p^6$ contributions to
simple processes.
| [
{
"created": "Mon, 22 Aug 1994 20:24:01 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Fearing",
"H. W.",
""
],
[
"Scherer",
"S.",
""
]
] | We have derived the most general chirally invariant Lagrangian ${\cal L}_6$ for the meson sector at order $p^6$. The result provides an extension of the standard Gasser-Leutwyler Lagrangian ${\cal L}_4$ to one higher order, including as well all the odd intrinsic parity terms in the Lagrangian. The most difficult part of the derivation was developing a systematic strategy so as to get all of the independent terms and eliminate the redundant ones in an efficient way. The 'equation of motion' terms, which are redundant in the sense that they can be transformed away via field transformations, are separated out explicitly. The resulting Lagrangian has been separated into groupings of terms contributing to increasingly more complicated processes, so that one does not have to deal with the full result when calculating $p^6$ contributions to simple processes. |
hep-ph/9911400 | Hartmut Wittig | Hartmut Wittig | Lattice Gauge Theory | 20 pages, 12 postscript figures, plenary talk presented at
International Europhysics Conference on High-Energy Physics, Tampere,
Finland, 15--21 July 1999; more references added | null | null | OUTP-99-60P | hep-ph hep-lat | null | The status of lattice calculations in Quantum Field Theory is reviewed. A
major part is devoted to recent progress in formulating exact chiral symmetry
on the lattice. Another topic which has received a lot of attention is the
influence of dynamical quark effects. Attempts to quantify these effects for
the light hadron spectrum and flavour singlet amplitudes are discussed, as well
as other expected qualitative features of simulations with dynamical quarks.
The remaining parts of the review include recent results for the light quark
masses using non-perturbative renormalisation and the spectrum of glueballs and
heavy hybrids computed using anisotropic lattices.
| [
{
"created": "Thu, 18 Nov 1999 12:44:39 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Dec 1999 18:36:50 GMT",
"version": "v2"
},
{
"created": "Sun, 19 Dec 1999 17:58:16 GMT",
"version": "v3"
}
] | 2007-05-23 | [
[
"Wittig",
"Hartmut",
""
]
] | The status of lattice calculations in Quantum Field Theory is reviewed. A major part is devoted to recent progress in formulating exact chiral symmetry on the lattice. Another topic which has received a lot of attention is the influence of dynamical quark effects. Attempts to quantify these effects for the light hadron spectrum and flavour singlet amplitudes are discussed, as well as other expected qualitative features of simulations with dynamical quarks. The remaining parts of the review include recent results for the light quark masses using non-perturbative renormalisation and the spectrum of glueballs and heavy hybrids computed using anisotropic lattices. |
1212.4887 | Farvah Mahmoudi | A. Arbey, M. Battaglia, F. Mahmoudi, D. Martinez Santos | Supersymmetry confronts Bs -> mu+mu-: Present and future status | 19 pages, 11 figures, 2 tables. v2: references added | Phys. Rev. D87 (2013) 035026 | 10.1103/PhysRevD.87.035026 | CERN-PH-TH/2012-346 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The purely leptonic rare decay Bs -> mu+mu- is very sensitive to
supersymmetric contributions which are free from the helicity suppression of
its Standard Model diagrams. The recent observation of the decay by the LHCb
experiment and the first determination of its branching fraction motivate a
review of their impact on the viable parameter space of supersymmetry. In this
paper we discuss the implications of the present and expected future accuracy
on BR(Bs -> mu+mu-) for constrained and unconstrained MSSM scenarios, in
relation to the results from direct SUSY searches and the Higgs data at the
LHC. While the constraints from BR(Bs -> mu+mu-) can be very important in
specific SUSY regions, we show that the current result, and even foreseen
future improvements in its accuracy, will leave a major fraction of the SUSY
parameter space, compatible with the results of direct searches, unconstrained.
We also highlight the complementarity of the Bs -> mu+mu- decay with direct
SUSY searches.
| [
{
"created": "Thu, 20 Dec 2012 00:04:44 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Feb 2013 20:02:37 GMT",
"version": "v2"
}
] | 2013-02-25 | [
[
"Arbey",
"A.",
""
],
[
"Battaglia",
"M.",
""
],
[
"Mahmoudi",
"F.",
""
],
[
"Santos",
"D. Martinez",
""
]
] | The purely leptonic rare decay Bs -> mu+mu- is very sensitive to supersymmetric contributions which are free from the helicity suppression of its Standard Model diagrams. The recent observation of the decay by the LHCb experiment and the first determination of its branching fraction motivate a review of their impact on the viable parameter space of supersymmetry. In this paper we discuss the implications of the present and expected future accuracy on BR(Bs -> mu+mu-) for constrained and unconstrained MSSM scenarios, in relation to the results from direct SUSY searches and the Higgs data at the LHC. While the constraints from BR(Bs -> mu+mu-) can be very important in specific SUSY regions, we show that the current result, and even foreseen future improvements in its accuracy, will leave a major fraction of the SUSY parameter space, compatible with the results of direct searches, unconstrained. We also highlight the complementarity of the Bs -> mu+mu- decay with direct SUSY searches. |
hep-ph/9402228 | Derek Leinweber | Derek B. Leinweber | Hadron Electromagnetic Structure: Shedding Light on Models and their
Mechanisms | Lattice '93 presentation. UU-File is a single postscript file of a 3
page manuscript including figures. Ohio State U. PP #93-1122 | null | 10.1016/0920-5632(94)90397-2 | null | hep-ph hep-lat | null | Strange quark contributions to the proton magnetic moment are estimated from
a consideration of baryon magnetic moment sum rules. The environment
sensitivity of quark contributions to baryon moments is emphasized. Pion cloud
contributions to proton charge radii are examined in the framework of Chiral
Perturbation Theory. The absence of scalar-diquark clustering in the nucleon is
discussed.
| [
{
"created": "Fri, 4 Feb 1994 14:58:22 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Leinweber",
"Derek B.",
""
]
] | Strange quark contributions to the proton magnetic moment are estimated from a consideration of baryon magnetic moment sum rules. The environment sensitivity of quark contributions to baryon moments is emphasized. Pion cloud contributions to proton charge radii are examined in the framework of Chiral Perturbation Theory. The absence of scalar-diquark clustering in the nucleon is discussed. |
hep-ph/0411274 | Andre de Gouvea | Andre de Gouvea (Northwestern U.) | 2004 TASI Lectures on Neutrino Physics | 62 pages, 17 figures | null | null | NUHEP-TH/04-17 | hep-ph | null | I discuss, in a semi-pedagogical way, our current understanding of neutrino
physics. I present a brief history of how the neutrino came to be ``invented''
and observed, and discuss the evidence that led to the recent discovery that
neutrinos change flavor. I then spend some time presenting mass-induced
neutrino flavor change (neutrino oscillation), and how it pieces all the
neutrino puzzles except for the LSND anomaly, which is also briefly discussed.
I conclude by highlighting the importance of determining the nature of the
neutrinos, i.e., are they Dirac or Majorana fermions.
| [
{
"created": "Sat, 20 Nov 2004 17:12:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"de Gouvea",
"Andre",
"",
"Northwestern U."
]
] | I discuss, in a semi-pedagogical way, our current understanding of neutrino physics. I present a brief history of how the neutrino came to be ``invented'' and observed, and discuss the evidence that led to the recent discovery that neutrinos change flavor. I then spend some time presenting mass-induced neutrino flavor change (neutrino oscillation), and how it pieces all the neutrino puzzles except for the LSND anomaly, which is also briefly discussed. I conclude by highlighting the importance of determining the nature of the neutrinos, i.e., are they Dirac or Majorana fermions. |
1507.07985 | Xiang Liu | Bo Wang, Hao Xu, Xiang Liu, Dian-Yong Chen, Susana Coito and Estia
Eichten | Using $X(3823)\to J/\psi\pi^+\pi^-$ to identify coupled-channel effects | 8 pages, 1 table, 5 figures. Accepted by Frontiers of Physics | Front. Phys. 11, 111402 (2016) | 10.1007/s11467-016-0564-7 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Very recently, the Belle and BESIII experiments observed a new
charmonium-like state $X(3823)$, which is a good candidate for the $D$-wave
charmonium $\psi(1^3D_2)$. Because the $X(3823)$ is just near the $D\bar{D}^*$
threshold, the decay $X(3823)\to J/\psi\pi^+\pi^-$ can be a golden channel to
test the significance of coupled-channel effects. In this work, this decay is
considered including both the hidden-charm dipion and the usual quantum
chromodynamics multipole expansion (QCDME) contributions. The partial decay
width, the dipion invariant mass spectrum distribution
$\mathrm{d}\Gamma[X(3823)\to J/\psi\pi^+\pi^-]/\mathrm{d}m_{\pi^+\pi^-}$, and
the corresponding $\mathrm{d}\Gamma[X(3823)\to
J/\psi\pi^+\pi^-]/\mathrm{d}\cos\theta$ distribution are computed. Many
parameters are determined from existing experimental data, so the results
depend mainly only on one unknown phase between the QCDME and hidden-charm
dipion amplitudes.
| [
{
"created": "Tue, 28 Jul 2015 23:28:44 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Jul 2015 02:41:14 GMT",
"version": "v2"
},
{
"created": "Thu, 28 Jan 2016 03:45:26 GMT",
"version": "v3"
},
{
"created": "Tue, 2 Feb 2016 08:28:36 GMT",
"version": "v4"
}
] | 2016-03-01 | [
[
"Wang",
"Bo",
""
],
[
"Xu",
"Hao",
""
],
[
"Liu",
"Xiang",
""
],
[
"Chen",
"Dian-Yong",
""
],
[
"Coito",
"Susana",
""
],
[
"Eichten",
"Estia",
""
]
] | Very recently, the Belle and BESIII experiments observed a new charmonium-like state $X(3823)$, which is a good candidate for the $D$-wave charmonium $\psi(1^3D_2)$. Because the $X(3823)$ is just near the $D\bar{D}^*$ threshold, the decay $X(3823)\to J/\psi\pi^+\pi^-$ can be a golden channel to test the significance of coupled-channel effects. In this work, this decay is considered including both the hidden-charm dipion and the usual quantum chromodynamics multipole expansion (QCDME) contributions. The partial decay width, the dipion invariant mass spectrum distribution $\mathrm{d}\Gamma[X(3823)\to J/\psi\pi^+\pi^-]/\mathrm{d}m_{\pi^+\pi^-}$, and the corresponding $\mathrm{d}\Gamma[X(3823)\to J/\psi\pi^+\pi^-]/\mathrm{d}\cos\theta$ distribution are computed. Many parameters are determined from existing experimental data, so the results depend mainly only on one unknown phase between the QCDME and hidden-charm dipion amplitudes. |
2304.13325 | Shilpa Jangid | Shilpa Jangid, Hiroshi Okada | Exploring CP-violation in $Y=0$ inert triplet with real singlet | 25 pages, 7 figures | Phys.Rev.D 108 (2023) 5, 055025 | 10.1103/PhysRevD.108.055025 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article, we examine the Standard Model extended with a $Y=0$ Higgs
triplet and a real singlet. We consider the Higgs triplet to be odd under the
$Z_2$ symmetry, and hence the lightest stable particle from the inert triplet
becomes the dark matter candidate, whereas the real singlet is considered to be
even under the $Z_2$ symmetry. A dimension-5 effective term is introduced with
the help of a real singlet, which breaks the CP symmetry and gives an
additional source of CP-violation in the fermion sector. The phase transition
proceeds in two-steps, with the symmetry breaking in the singlet direction
occurring first and later leading to the usual electroweak symmetry breaking
minima, while electroweak baryogenesis is associated with the second step. The
parameters chosen for the electroweak phase transition are found to be
consistent with the Planck scale stability and the perturbativity using
two-loop $\beta$-functions. The DM mass bound for inert triplet, i.e., 1.2 TeV
(below which it is under abundance), also comes out to be consistent with the
strongly first-order phase transition, which was not possible solely with inert
triplet. The upper bound on the triplet mass comes out to be $\leq 3.8$ TeV,
which satisfies the strongly first-order phase transition. This particular
benchmark point also satisfies the correct baryon asymmetry of the Universe
$(6.13 \times 10^{-11})$, and the gravitational wave spectrum also lies within
the detectable frequency range of LISA $(6.978 \times 10^{-4} - 1.690 \times
10^{-2} )$ Hz and BBO $(2.80\times 10^{-3}-1.096)$ Hz experiments.
| [
{
"created": "Wed, 26 Apr 2023 06:55:35 GMT",
"version": "v1"
},
{
"created": "Sun, 1 Oct 2023 09:04:15 GMT",
"version": "v2"
}
] | 2023-10-03 | [
[
"Jangid",
"Shilpa",
""
],
[
"Okada",
"Hiroshi",
""
]
] | In this article, we examine the Standard Model extended with a $Y=0$ Higgs triplet and a real singlet. We consider the Higgs triplet to be odd under the $Z_2$ symmetry, and hence the lightest stable particle from the inert triplet becomes the dark matter candidate, whereas the real singlet is considered to be even under the $Z_2$ symmetry. A dimension-5 effective term is introduced with the help of a real singlet, which breaks the CP symmetry and gives an additional source of CP-violation in the fermion sector. The phase transition proceeds in two-steps, with the symmetry breaking in the singlet direction occurring first and later leading to the usual electroweak symmetry breaking minima, while electroweak baryogenesis is associated with the second step. The parameters chosen for the electroweak phase transition are found to be consistent with the Planck scale stability and the perturbativity using two-loop $\beta$-functions. The DM mass bound for inert triplet, i.e., 1.2 TeV (below which it is under abundance), also comes out to be consistent with the strongly first-order phase transition, which was not possible solely with inert triplet. The upper bound on the triplet mass comes out to be $\leq 3.8$ TeV, which satisfies the strongly first-order phase transition. This particular benchmark point also satisfies the correct baryon asymmetry of the Universe $(6.13 \times 10^{-11})$, and the gravitational wave spectrum also lies within the detectable frequency range of LISA $(6.978 \times 10^{-4} - 1.690 \times 10^{-2} )$ Hz and BBO $(2.80\times 10^{-3}-1.096)$ Hz experiments. |
hep-ph/9508331 | Urjit A Yajnik | U. A. yajnik (IIT Bombay) | Baryogenesis at the Electroweak Scale | 20 pages. Plain TeX. Figures available upon requaest | null | null | IITB-Th-9503 | hep-ph | null | The realisation that the electroweak anomaly can induce significant baryon
number violation at high temperature and that the standard models of particle
physics and cosmology contain all the ingredients needed for baryogenesis has
led to vigourous search for viable models. The conclusions so far are that the
Standard Model of particle physics cannot produce baryon asymmetry of required
magnitude. It has too little $CP$ violation and sphaleronic transitions wipe
out any asymmetry produced if the Higgs is heavier than about 50 GeV, a range
already excluded by accelerator experiments. We review the sphaleron solution,
its connection to the high temperature anomalous rate and then summarise
possibilities where phenomenologically testable extensions of the Standard
Model may yet explain the baryon asymmetry of the Universe.
| [
{
"created": "Mon, 21 Aug 1995 06:11:12 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"yajnik",
"U. A.",
"",
"IIT Bombay"
]
] | The realisation that the electroweak anomaly can induce significant baryon number violation at high temperature and that the standard models of particle physics and cosmology contain all the ingredients needed for baryogenesis has led to vigourous search for viable models. The conclusions so far are that the Standard Model of particle physics cannot produce baryon asymmetry of required magnitude. It has too little $CP$ violation and sphaleronic transitions wipe out any asymmetry produced if the Higgs is heavier than about 50 GeV, a range already excluded by accelerator experiments. We review the sphaleron solution, its connection to the high temperature anomalous rate and then summarise possibilities where phenomenologically testable extensions of the Standard Model may yet explain the baryon asymmetry of the Universe. |
2111.07421 | David London | C.P. Burgess, Serge Hamoudou, Jacky Kumar and David London | Beyond SMEFT with $b \to c \,\tau^- {\bar\nu}$ | 6 pages, 1 figure. Changes: a few oversights corrected (thanks to
Christopher Murphy), conclusions unchanged. Mar. 29: references added | null | null | UdeM-GPP-TH-21-290 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Electroweak interactions assign a central role to the gauge group $SU(2)_L
\times U(1)_Y$, which is either realized linearly (SMEFT) or nonlinearly (e.g.,
HEFT) in the effective theory obtained when new physics above the electroweak
scale is integrated out. Although the discovery of the Higgs boson has made
SMEFT the default assumption, nonlinear realization remains possible. The two
can be distinguished through their predictions for the size of certain
low-energy dimension-6 four-fermion operators: for these, HEFT predicts $O(1)$
couplings, while in SMEFT they are suppressed by a factor $v^2/\Lambda_{\rm
NP}^2$, where $v$ is the Higgs vev. One such operator, $O_V^{LR} \equiv ({\bar
\tau} \gamma^\mu P_L \nu )\, ( {\bar c} \gamma_\mu P_R b )$, contributes to $b
\to c \,\tau^- {\bar\nu}$. We show that present constraints permit its
non-SMEFT coefficient to have a HEFTy size. We also note that the angular
distribution in ${\bar B} \to D^* (\to D \pi') \, \tau^{-} (\to \pi^- \nu_\tau)
{\bar\nu}_\tau$ contains enough information to extract the coefficients of all
new-physics operators. Future measurements of this angular distribution can
therefore tell us if non-SMEFT new physics is really necessary.
| [
{
"created": "Sun, 14 Nov 2021 19:03:54 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Nov 2021 18:05:13 GMT",
"version": "v2"
},
{
"created": "Tue, 29 Mar 2022 15:27:47 GMT",
"version": "v3"
}
] | 2022-03-30 | [
[
"Burgess",
"C. P.",
""
],
[
"Hamoudou",
"Serge",
""
],
[
"Kumar",
"Jacky",
""
],
[
"London",
"David",
""
]
] | Electroweak interactions assign a central role to the gauge group $SU(2)_L \times U(1)_Y$, which is either realized linearly (SMEFT) or nonlinearly (e.g., HEFT) in the effective theory obtained when new physics above the electroweak scale is integrated out. Although the discovery of the Higgs boson has made SMEFT the default assumption, nonlinear realization remains possible. The two can be distinguished through their predictions for the size of certain low-energy dimension-6 four-fermion operators: for these, HEFT predicts $O(1)$ couplings, while in SMEFT they are suppressed by a factor $v^2/\Lambda_{\rm NP}^2$, where $v$ is the Higgs vev. One such operator, $O_V^{LR} \equiv ({\bar \tau} \gamma^\mu P_L \nu )\, ( {\bar c} \gamma_\mu P_R b )$, contributes to $b \to c \,\tau^- {\bar\nu}$. We show that present constraints permit its non-SMEFT coefficient to have a HEFTy size. We also note that the angular distribution in ${\bar B} \to D^* (\to D \pi') \, \tau^{-} (\to \pi^- \nu_\tau) {\bar\nu}_\tau$ contains enough information to extract the coefficients of all new-physics operators. Future measurements of this angular distribution can therefore tell us if non-SMEFT new physics is really necessary. |
1804.06140 | Anton Rebhan | R. Baier, A. Rebhan, M. W\"odlinger | Light-by-Light Scattering in the Presence of Magnetic Fields | 23 pages, 6 figures (v3: minor improvements, references added) | Phys. Rev. D 98, 056001 (2018) | 10.1103/PhysRevD.98.056001 | BI-TP 2018/02, TUW-18-04 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The low-energy light-by-light cross section as determined by the nonlinear
Euler-Heisenberg QED Lagrangian is evaluated in the presence of constant
magnetic fields in the center-of-mass system of the colliding photons. This
cross section has a complicated dependence on directions and polarizations. The
overall magnitude decreases as the magnetic field is increased from zero, but
this trend is reversed for ultrastrong magnetic fields $B\gtrsim B_c$, where
the cross section eventually grows quadratically with the magnetic field
strength perpendicular to the collision axis. This effect is due to
interactions involving the lowest Landau level of virtual Dirac particles; it
is absent in scalar QED. An even more dramatic effect is found for virtual
charged vector mesons where the one-loop cross section diverges at the critical
field strength due to an instability of the lowest Landau level and the
possibility of the formation of a superconducting vacuum state. We also discuss
(the absence of) implications for the recent observation of light-by-light
scattering in heavy-ion collisions.
| [
{
"created": "Tue, 17 Apr 2018 09:56:10 GMT",
"version": "v1"
},
{
"created": "Thu, 3 May 2018 17:24:47 GMT",
"version": "v2"
},
{
"created": "Tue, 14 Aug 2018 09:33:10 GMT",
"version": "v3"
}
] | 2018-09-12 | [
[
"Baier",
"R.",
""
],
[
"Rebhan",
"A.",
""
],
[
"Wödlinger",
"M.",
""
]
] | The low-energy light-by-light cross section as determined by the nonlinear Euler-Heisenberg QED Lagrangian is evaluated in the presence of constant magnetic fields in the center-of-mass system of the colliding photons. This cross section has a complicated dependence on directions and polarizations. The overall magnitude decreases as the magnetic field is increased from zero, but this trend is reversed for ultrastrong magnetic fields $B\gtrsim B_c$, where the cross section eventually grows quadratically with the magnetic field strength perpendicular to the collision axis. This effect is due to interactions involving the lowest Landau level of virtual Dirac particles; it is absent in scalar QED. An even more dramatic effect is found for virtual charged vector mesons where the one-loop cross section diverges at the critical field strength due to an instability of the lowest Landau level and the possibility of the formation of a superconducting vacuum state. We also discuss (the absence of) implications for the recent observation of light-by-light scattering in heavy-ion collisions. |
hep-ph/9307295 | null | J. Bernabeu, J. Korner, A. Pilaftsis, K. Schilcher | Universality-Breaking Effects in Leptonic Z Decays | MZ-TH/93-04 #, LaTeX, 14 p. (2 Figs) | Phys.Rev.Lett. 71 (1993) 2695-2698 | 10.1103/PhysRevLett.71.2695 | null | hep-ph | null | We analyze the possibility of universality violation in diagonal leptonic
decays of the $Z$ boson, in the context of interfamily "see-saw" models. In a
minimal extension of the Standard Model with right-handed neutrino fields, we
find that universality-breaking effects increase quadratically with the heavy
Majorana neutrino mass and may be observed in the running $LEP$ experiments.
| [
{
"created": "Mon, 19 Jul 1993 14:22:00 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Bernabeu",
"J.",
""
],
[
"Korner",
"J.",
""
],
[
"Pilaftsis",
"A.",
""
],
[
"Schilcher",
"K.",
""
]
] | We analyze the possibility of universality violation in diagonal leptonic decays of the $Z$ boson, in the context of interfamily "see-saw" models. In a minimal extension of the Standard Model with right-handed neutrino fields, we find that universality-breaking effects increase quadratically with the heavy Majorana neutrino mass and may be observed in the running $LEP$ experiments. |
1809.10058 | A. V. Luchinsky | A. V. Berezhnoy, A. K. Likhoded, A. V. Luchinsky | Doubly heavy baryons at LHC | Minor changes; some references added | Phys. Rev. D 98, 113004 (2018) | 10.1103/PhysRevD.98.113004 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The theoretical analysis of production, lifetime, and decays of doubly heavy
baryons is presented. The lifetime of $\Xi_{cc}^{++}$ baryon recently measured
by the LHCb Collaboration is used to estimate the lifetimes of other doubly
heavy baryons. The production and the possibility of observation of $\Xi_{bc}$
baryon at LHC are discussed.
| [
{
"created": "Wed, 26 Sep 2018 15:15:26 GMT",
"version": "v1"
},
{
"created": "Thu, 4 Oct 2018 14:26:10 GMT",
"version": "v2"
},
{
"created": "Tue, 27 Nov 2018 14:47:24 GMT",
"version": "v3"
}
] | 2018-12-19 | [
[
"Berezhnoy",
"A. V.",
""
],
[
"Likhoded",
"A. K.",
""
],
[
"Luchinsky",
"A. V.",
""
]
] | The theoretical analysis of production, lifetime, and decays of doubly heavy baryons is presented. The lifetime of $\Xi_{cc}^{++}$ baryon recently measured by the LHCb Collaboration is used to estimate the lifetimes of other doubly heavy baryons. The production and the possibility of observation of $\Xi_{bc}$ baryon at LHC are discussed. |
1204.5782 | Sergey Sibiryakov | Grigory Rubtsov, Petr Satunin and Sergey Sibiryakov | On calculation of cross sections in Lorentz violating theories | 23 pages, 1 figure | null | 10.1103/PhysRevD.86.085012 | null | hep-ph astro-ph.HE hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We develop a systematic approach to the calculation of scattering cross
sections in theories with violation of the Lorentz invariance taking into
account the whole information about the theory Lagrangian. As an illustration
we derive the Feynman rules and formulas for sums over polarizations in spinor
electrodynamics with Lorentz violating operators of dimensions four and six.
These rules are applied to compute the probabilities of several astrophysically
relevant processes. We calculate the rates of photon decay and vacuum Cherenkov
radiation along with the cross sections of electron-positron pair production on
background radiation and in the Coulomb field. The latter process is essential
for detection of photon-induced air showers in the atmosphere.
| [
{
"created": "Wed, 25 Apr 2012 21:54:15 GMT",
"version": "v1"
}
] | 2015-06-04 | [
[
"Rubtsov",
"Grigory",
""
],
[
"Satunin",
"Petr",
""
],
[
"Sibiryakov",
"Sergey",
""
]
] | We develop a systematic approach to the calculation of scattering cross sections in theories with violation of the Lorentz invariance taking into account the whole information about the theory Lagrangian. As an illustration we derive the Feynman rules and formulas for sums over polarizations in spinor electrodynamics with Lorentz violating operators of dimensions four and six. These rules are applied to compute the probabilities of several astrophysically relevant processes. We calculate the rates of photon decay and vacuum Cherenkov radiation along with the cross sections of electron-positron pair production on background radiation and in the Coulomb field. The latter process is essential for detection of photon-induced air showers in the atmosphere. |
1012.0258 | Roberto Bonciani | R. Bonciani, A. Ferroglia, T. Gehrmann, A. von Manteuffel, C. Studerus | Two-Loop Corrections to Top-Antitop Production at Hadron Colliders | Talk presented at the 35th International Conference of High Energy
Physics - ICHEP2010, July 22-28, 2010, Paris France | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The status of the theoretical predictions for the top-anti top production in
hadronic collisions is shortly reviewed, paying a articular attention to the
analytic calculation of the two-loop QCD corrections to the parton-level matrix
elements.
| [
{
"created": "Wed, 1 Dec 2010 17:52:32 GMT",
"version": "v1"
}
] | 2010-12-02 | [
[
"Bonciani",
"R.",
""
],
[
"Ferroglia",
"A.",
""
],
[
"Gehrmann",
"T.",
""
],
[
"von Manteuffel",
"A.",
""
],
[
"Studerus",
"C.",
""
]
] | The status of the theoretical predictions for the top-anti top production in hadronic collisions is shortly reviewed, paying a articular attention to the analytic calculation of the two-loop QCD corrections to the parton-level matrix elements. |
2405.19447 | Giulio Barni Mr | Aleksandr Azatov, Giulio Barni, Rudin Petrossian-Byrne | NLO friction in symmetry restoring phase transitions | 17 pages + appendices | null | null | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Interactions between bubbles/domain walls and the surrounding medium are a
topic of active research, particularly as they apply to friction effects on
accelerated expansion during first-order phase transitions. In this paper, we
analyze for the first time friction pressure on relativistic walls in phase
transitions where gauge symmetry is restored, particularly motivated by the
observation that this pressure can, in principle, be negative at leading order,
since some particles lose mass by definition as they cross into the new phase.
We find, however, that at NLO, the soft emission of vectors from a charged
current leads to positive pressure scaling as the wall's Lorentz boost factor
$\gamma_w$, similar to the case of gauge symmetry breaking. Contrary to the
latter case, we find that the dominant contribution in single emission is safe
from IR divergences and exhibits a much stronger dependence on the wall shape.
Finally, we argue that in any phase transition, no multi-particle process on
the wall can impart negative pressure greater than the leading order result, in
the asymptotic limit of large velocity.
| [
{
"created": "Wed, 29 May 2024 18:47:24 GMT",
"version": "v1"
}
] | 2024-05-31 | [
[
"Azatov",
"Aleksandr",
""
],
[
"Barni",
"Giulio",
""
],
[
"Petrossian-Byrne",
"Rudin",
""
]
] | Interactions between bubbles/domain walls and the surrounding medium are a topic of active research, particularly as they apply to friction effects on accelerated expansion during first-order phase transitions. In this paper, we analyze for the first time friction pressure on relativistic walls in phase transitions where gauge symmetry is restored, particularly motivated by the observation that this pressure can, in principle, be negative at leading order, since some particles lose mass by definition as they cross into the new phase. We find, however, that at NLO, the soft emission of vectors from a charged current leads to positive pressure scaling as the wall's Lorentz boost factor $\gamma_w$, similar to the case of gauge symmetry breaking. Contrary to the latter case, we find that the dominant contribution in single emission is safe from IR divergences and exhibits a much stronger dependence on the wall shape. Finally, we argue that in any phase transition, no multi-particle process on the wall can impart negative pressure greater than the leading order result, in the asymptotic limit of large velocity. |
0901.3818 | Wenyu Wang | Wenyu Wang, Zhaohua Xiong, Jin Min Yang | Residual effects of heavy sparticles in the bottom quark Yukawa
coupling: a comparative study for the MSSM and NMSSM | Version in PLB (discussions added) | Phys.Lett.B680:167-171,2009 | 10.1016/j.physletb.2009.08.048 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | If the sparticles are relatively heavy (a few TeV) while the Higgs sector is
not so heavy ($m_A$ is not so large), the Higgs boson Yukawa couplings can
harbor sizable quantum effects of sparticles and these large residual effects
may play a special role in probing supersymmetry at foreseeable colliders. In
this work, focusing on the supersymmetric QCD effects in the hbb coupling (h is
the lightest CP-even Higgs boson), we give a comparative study for the two
popular supersymmetric models: the MSSM and NMSSM. While for both models the
supersymmetric QCD can leave over large residual quantum effects in hbb
coupling, the NMSSM can allow for a much broader region of such effects. Since
these residual effects can be over 20% for the hbb coupling (and thus over 40%
for the ratio $Br(h->bb)/Br(h->\tau \tau)), future measurements may unravel the
effects of heavy sparticles or even distinguish the two models.
| [
{
"created": "Sat, 24 Jan 2009 10:14:38 GMT",
"version": "v1"
},
{
"created": "Thu, 27 Aug 2009 14:51:42 GMT",
"version": "v2"
}
] | 2010-04-05 | [
[
"Wang",
"Wenyu",
""
],
[
"Xiong",
"Zhaohua",
""
],
[
"Yang",
"Jin Min",
""
]
] | If the sparticles are relatively heavy (a few TeV) while the Higgs sector is not so heavy ($m_A$ is not so large), the Higgs boson Yukawa couplings can harbor sizable quantum effects of sparticles and these large residual effects may play a special role in probing supersymmetry at foreseeable colliders. In this work, focusing on the supersymmetric QCD effects in the hbb coupling (h is the lightest CP-even Higgs boson), we give a comparative study for the two popular supersymmetric models: the MSSM and NMSSM. While for both models the supersymmetric QCD can leave over large residual quantum effects in hbb coupling, the NMSSM can allow for a much broader region of such effects. Since these residual effects can be over 20% for the hbb coupling (and thus over 40% for the ratio $Br(h->bb)/Br(h->\tau \tau)), future measurements may unravel the effects of heavy sparticles or even distinguish the two models. |
2303.12630 | Vadim Guzey | K.J. Eskola (Jyvaskyla U. and Helsinki U.), V. Guzey (Jyvaskyla U. and
Helsinki U.), T. L\"oyt\"ainen (Jyvaskyla U. and Helsinki U.), H. Paukkunen
(Jyvaskyla U. and Helsinki U.), C.A. Flett (IJCLab, Orsay) | Exclusive heavy vector meson photoproduction on nuclei in NLO
perturbative QCD | 10 pages, 6 figures. Contribution to Proceedings of XXIX Cracow
EPIPHANY Conference on Physics at the Electron-Ion Collider and Future
Facilities, Cracow, Poland, January 16-19, 2023 | null | null | null | hep-ph hep-ex nucl-ex | http://creativecommons.org/licenses/by/4.0/ | We make predictions for the cross section of coherent $J/\psi$
photoproduction in Pb-Pb and O-O ultraperipheral collisions (UPCs) at the LHC
as a function of the $J/\psi$ rapidity $y$ in the framework of collinear
factorization and next-to-leading order (NLO) perturbative QCD. We quantify the
strong scale dependence and significant uncertainties due to nuclear PDFs and
show that our approach provides a reasonable description of the LHC data on
coherent $J/\psi$ photoproduction in Pb-Pb UPCs. We demonstrate that these
uncertainties are reduced by approximately a factor of 10 in the scaled ratio
of the O-O and Pb-Pb UPC cross sections. Our analysis indicates the dominance
of the quark contribution to the UPC cross section at central rapidities, which
affects the interpretation of the UPC data.
| [
{
"created": "Wed, 22 Mar 2023 15:10:47 GMT",
"version": "v1"
}
] | 2023-03-23 | [
[
"Eskola",
"K. J.",
"",
"Jyvaskyla U. and Helsinki U."
],
[
"Guzey",
"V.",
"",
"Jyvaskyla U. and\n Helsinki U."
],
[
"Löytäinen",
"T.",
"",
"Jyvaskyla U. and Helsinki U."
],
[
"Paukkunen",
"H.",
"",
"Jyvaskyla U. and Helsinki U."
],
[
"Flett",
"C. A.",
"",
"IJCLab, Orsay"
]
] | We make predictions for the cross section of coherent $J/\psi$ photoproduction in Pb-Pb and O-O ultraperipheral collisions (UPCs) at the LHC as a function of the $J/\psi$ rapidity $y$ in the framework of collinear factorization and next-to-leading order (NLO) perturbative QCD. We quantify the strong scale dependence and significant uncertainties due to nuclear PDFs and show that our approach provides a reasonable description of the LHC data on coherent $J/\psi$ photoproduction in Pb-Pb UPCs. We demonstrate that these uncertainties are reduced by approximately a factor of 10 in the scaled ratio of the O-O and Pb-Pb UPC cross sections. Our analysis indicates the dominance of the quark contribution to the UPC cross section at central rapidities, which affects the interpretation of the UPC data. |
1201.2920 | Jacopo Ghiglieri | Jacopo Ghiglieri | Effective Field Theories of QCD for Heavy Quarkonia at Finite
Temperature | PhD thesis, Technical University of Munich. 230 pages | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Quarkonium suppression is one of the most investigated probes of the medium
produced in heavy-ion collisions. In this thesis we extend the well-established
and successful zero temperature framework of Non-Relativistic (NR) Effective
Field Theories (EFTs) (NRQCD, pNRQCD) for the study of heavy quarkonia
(production, spectroscopy, decays, ...) to finite temperatures. This is
achieved by integrating out in sequence the scales that characterize a NR bound
state and those that are typical of a thermal medium, in the possible
hierarchies that are relevant for quarkonia in the quark-gluon plasma. Within
this framework we show how the potential that governs the evolution of the
quark-antiquark pair is derived from QCD in a modern and rigorous way, thereby
bridging the gap between phenomenological potential models and QCD. We show how
the EFTs can be systematically improved and how effects that cannot be encoded
in a potential arise naturally in the EFT, giving rise to new mechanisms of
dissociation. We use this EFT framework to compute the spectrum and width of
quarkonia in a particular setting that is relevant for the phenomenology of the
ground states of bottomonium at the LHC. We also analyze within this framework
the correlator of Polyakov loops, which is related to the thermodynamical free
energy of heavy quark-antiquark pairs in the medium. As such, lattice
computations thereof were frequently used as input for potential models. With
our approach we are able to clarify the relation between these free energies
and the real-time potential describing the dynamics of quarkonia, finding that
the two are different not only in the important imaginary parts, that the
former completely lack, but also in the real parts.
| [
{
"created": "Fri, 13 Jan 2012 19:18:23 GMT",
"version": "v1"
}
] | 2012-01-16 | [
[
"Ghiglieri",
"Jacopo",
""
]
] | Quarkonium suppression is one of the most investigated probes of the medium produced in heavy-ion collisions. In this thesis we extend the well-established and successful zero temperature framework of Non-Relativistic (NR) Effective Field Theories (EFTs) (NRQCD, pNRQCD) for the study of heavy quarkonia (production, spectroscopy, decays, ...) to finite temperatures. This is achieved by integrating out in sequence the scales that characterize a NR bound state and those that are typical of a thermal medium, in the possible hierarchies that are relevant for quarkonia in the quark-gluon plasma. Within this framework we show how the potential that governs the evolution of the quark-antiquark pair is derived from QCD in a modern and rigorous way, thereby bridging the gap between phenomenological potential models and QCD. We show how the EFTs can be systematically improved and how effects that cannot be encoded in a potential arise naturally in the EFT, giving rise to new mechanisms of dissociation. We use this EFT framework to compute the spectrum and width of quarkonia in a particular setting that is relevant for the phenomenology of the ground states of bottomonium at the LHC. We also analyze within this framework the correlator of Polyakov loops, which is related to the thermodynamical free energy of heavy quark-antiquark pairs in the medium. As such, lattice computations thereof were frequently used as input for potential models. With our approach we are able to clarify the relation between these free energies and the real-time potential describing the dynamics of quarkonia, finding that the two are different not only in the important imaginary parts, that the former completely lack, but also in the real parts. |
1904.10061 | Emerson Luna | M. Broilo, D. A. Fagundes, E. G. S. Luna and M. J. Menon | Proton-proton forward scattering at the LHC | 5 pages, 2 figures, 1 table. Phenomenological approach revised,
results and conclusions changed, suggesting now the presence of Odderon
effects in forward scattering (once confirmed the TOTEM data at 13 TeV) | null | 10.1016/j.physletb.2019.135047 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently the TOTEM experiment at the LHC has released measurements at
$\sqrt{s} = 13$ TeV of the proton-proton total cross section, $\sigma_{tot}$,
and the ratio of the real to imaginary parts of the forward elastic amplitude,
$\rho$. Since then an intense debate on the $C$-parity asymptotic nature of the
scattering amplitude was initiated. We examine the proton-proton and the
antiproton-proton forward data above 10 GeV in the context of an eikonal
QCD-based model, where nonperturbative effects are readily included via a QCD
effective charge. We show that, despite an overall satisfactory description of
the forward data is obtained by a model in which the scattering amplitude is
dominated by only crossing-even elastic terms, there is evidence that the
introduction of a crossing-odd term may improve the agreement with the
measurements of $\rho$ at $\sqrt{s} = 13$ TeV. In the Regge language the
dominant even(odd)-under-crossing object is the so called Pomeron (Odderon).
| [
{
"created": "Mon, 22 Apr 2019 20:43:09 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Jun 2019 19:16:36 GMT",
"version": "v2"
},
{
"created": "Tue, 17 Sep 2019 17:24:43 GMT",
"version": "v3"
}
] | 2019-10-30 | [
[
"Broilo",
"M.",
""
],
[
"Fagundes",
"D. A.",
""
],
[
"Luna",
"E. G. S.",
""
],
[
"Menon",
"M. J.",
""
]
] | Recently the TOTEM experiment at the LHC has released measurements at $\sqrt{s} = 13$ TeV of the proton-proton total cross section, $\sigma_{tot}$, and the ratio of the real to imaginary parts of the forward elastic amplitude, $\rho$. Since then an intense debate on the $C$-parity asymptotic nature of the scattering amplitude was initiated. We examine the proton-proton and the antiproton-proton forward data above 10 GeV in the context of an eikonal QCD-based model, where nonperturbative effects are readily included via a QCD effective charge. We show that, despite an overall satisfactory description of the forward data is obtained by a model in which the scattering amplitude is dominated by only crossing-even elastic terms, there is evidence that the introduction of a crossing-odd term may improve the agreement with the measurements of $\rho$ at $\sqrt{s} = 13$ TeV. In the Regge language the dominant even(odd)-under-crossing object is the so called Pomeron (Odderon). |
hep-ph/0007032 | Vladimir Smirnov | V.A. Smirnov | Analytical Result for Dimensionally Regularized Massless Master Double
Box with One Leg off Shell | 10 pages, LaTeX with axodraw.sty, one reference is corrected | Phys.Lett.B491:130-136,2000 | 10.1016/S0370-2693(00)00997-7 | null | hep-ph hep-th | null | The dimensionally regularized massless double box Feynman diagram with powers
of propagators equal to one, one leg off the mass shell, i.e. with non-zero
q^2=p_1^2, and three legs on shell, p_i^2=0, i=2,3,4, is analytically
calculated for general values of q^2 and the Mandelstam variables s and t. An
explicit result is expressed through (generalized) polylogarithms, up to the
fourth order, dependent on rational combinations of q^2,s and t, and a
one-dimensional integral with a simple integrand consisting of logarithms and
dilogarithms.
| [
{
"created": "Tue, 4 Jul 2000 18:07:43 GMT",
"version": "v1"
},
{
"created": "Fri, 3 Nov 2000 18:35:07 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Smirnov",
"V. A.",
""
]
] | The dimensionally regularized massless double box Feynman diagram with powers of propagators equal to one, one leg off the mass shell, i.e. with non-zero q^2=p_1^2, and three legs on shell, p_i^2=0, i=2,3,4, is analytically calculated for general values of q^2 and the Mandelstam variables s and t. An explicit result is expressed through (generalized) polylogarithms, up to the fourth order, dependent on rational combinations of q^2,s and t, and a one-dimensional integral with a simple integrand consisting of logarithms and dilogarithms. |
hep-ph/0312345 | Cliff Burgess | C.P. Burgess N.S. Dzhalilov, M. Maltoni, T.I. Rashba, V.B. Semikoz, M.
Tortola and J.W.F. Valle | Neutrino Oscillations, Fluctuations and Solar Magneto-gravity Waves | Plenary talk presented at AHEP 2003, Valencia, Spain, October 2003 | null | null | McGill-03/29 | hep-ph | null | This review has two parts. The first part summarizes the current
observational constraints on fluctuations in the solar medium deep within the
solar Radiative Zone, and shows how the KamLAND and SNO-salt data combine to
make the experimental determination of the neutrino oscillation parameters
largely insensitive to prior assumptions about the nature of these
oscillations. As part of a search for plausible sources of solar fluctuations
to which neutrinos could be sensitive, the second part of the talk summarizes a
preliminary analysis of the influence of magnetic fields on helioseismic waves.
Using simplifying assumptions which should apply to modes in the solar
radiative zone, we find a resonance between Alfven waves and helioseismic
g-modes which potentially modifies the solar density profile fairly
significantly over comparatively short distance scales, too narrow to be ruled
out by present-day analyses of p-wave helioseismic spectra.
| [
{
"created": "Wed, 24 Dec 2003 21:18:28 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dzhalilov",
"C. P. Burgess N. S.",
""
],
[
"Maltoni",
"M.",
""
],
[
"Rashba",
"T. I.",
""
],
[
"Semikoz",
"V. B.",
""
],
[
"Tortola",
"M.",
""
],
[
"Valle",
"J. W. F.",
""
]
] | This review has two parts. The first part summarizes the current observational constraints on fluctuations in the solar medium deep within the solar Radiative Zone, and shows how the KamLAND and SNO-salt data combine to make the experimental determination of the neutrino oscillation parameters largely insensitive to prior assumptions about the nature of these oscillations. As part of a search for plausible sources of solar fluctuations to which neutrinos could be sensitive, the second part of the talk summarizes a preliminary analysis of the influence of magnetic fields on helioseismic waves. Using simplifying assumptions which should apply to modes in the solar radiative zone, we find a resonance between Alfven waves and helioseismic g-modes which potentially modifies the solar density profile fairly significantly over comparatively short distance scales, too narrow to be ruled out by present-day analyses of p-wave helioseismic spectra. |
1206.4233 | Berthold Stech | Berthold Stech | The mass of the Higgs boson in the trinification subgroup of E6 | 5 pages, version appearing in Phys. Rev. D | null | 10.1103/PhysRevD.86.055003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The extension of the standard model to SU(3)_L x SU(3)_R x SU(3)_C is
considered. Spontaneous symmetry breaking requires two Higgs field multiplets
with a strong hierarchical structure of vacuum expectation values. These vacuum
expectation values, some of them known from experiment, are used to construct
invariant potentials in form of a sum of individual potentials relevant at the
weak scale. As in a previous suggestion one may normalize the most important
individual potentials such that their mass eigenvalues agree with their very
large vacuum expectation values. In this case (for a wide class of parameters)
the scalar field corresponding to the standard model Higgs turns out to have
the precise mass value m_Higgs = v/sqrt(2) = 123 GeV at the weak scale. The
physical mass (pole mass) is larger and found to be 125 +/- 1.4 GeV.
| [
{
"created": "Tue, 19 Jun 2012 15:19:41 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Jul 2012 11:12:43 GMT",
"version": "v2"
},
{
"created": "Thu, 30 Aug 2012 18:31:46 GMT",
"version": "v3"
}
] | 2013-05-30 | [
[
"Stech",
"Berthold",
""
]
] | The extension of the standard model to SU(3)_L x SU(3)_R x SU(3)_C is considered. Spontaneous symmetry breaking requires two Higgs field multiplets with a strong hierarchical structure of vacuum expectation values. These vacuum expectation values, some of them known from experiment, are used to construct invariant potentials in form of a sum of individual potentials relevant at the weak scale. As in a previous suggestion one may normalize the most important individual potentials such that their mass eigenvalues agree with their very large vacuum expectation values. In this case (for a wide class of parameters) the scalar field corresponding to the standard model Higgs turns out to have the precise mass value m_Higgs = v/sqrt(2) = 123 GeV at the weak scale. The physical mass (pole mass) is larger and found to be 125 +/- 1.4 GeV. |
1107.0941 | Shabbar Raza | Nobuchika Okada, Shabbar Raza and Qaisar Shafi | Particle Spectroscopy of Supersymmetric SO(10) with Non-Universal
Gaugino Masses | 18 pages,10 figures, 9 tables | null | 10.1103/PhysRevD.84.095018 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the low scale particle spectroscopy of an SO(10) (or equivalently
SU(5)) inspired supersymmetric model with non-universal gaugino masses. The
model assumes minimal supergravity and contains the same number of fundamental
parameters as the constrained minimal supersymmetric model (CMSSM.) Realistic
solutions compatible with dark matter and other applicable experimental
constraints are shown to exist for both positive and negative signs of the MSSM
parameter mu. We present several benchmark points which will be tested at the
LHC and by the ongoing direct and indirect dark matter detection experiments.
| [
{
"created": "Tue, 5 Jul 2011 18:49:49 GMT",
"version": "v1"
}
] | 2013-05-29 | [
[
"Okada",
"Nobuchika",
""
],
[
"Raza",
"Shabbar",
""
],
[
"Shafi",
"Qaisar",
""
]
] | We examine the low scale particle spectroscopy of an SO(10) (or equivalently SU(5)) inspired supersymmetric model with non-universal gaugino masses. The model assumes minimal supergravity and contains the same number of fundamental parameters as the constrained minimal supersymmetric model (CMSSM.) Realistic solutions compatible with dark matter and other applicable experimental constraints are shown to exist for both positive and negative signs of the MSSM parameter mu. We present several benchmark points which will be tested at the LHC and by the ongoing direct and indirect dark matter detection experiments. |
1407.4588 | Nikonov Victor A. | V.V. Anisovich, M.A. Matveev, V.A. Nikonov | Hadron diffractive production at ultrahigh energies | 13 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Diffractive production is considered in the ultrahigh energy region where
pomeron exchange amplitudes are transformed into black disk ones due to
rescattering corrections. The corresponding corrections in hadron reactions
$h_1+h_3\to h_1+h_2+h_3$ with small momenta transferred ($q^2_{1\to 1}\sim
m^2/\ln^2s$, $q^2_{3\to 3}\sim m^2/\ln^2s$) are calculated in terms of the
$K$-matrix technique modified for ultrahigh energies. Small values of the
momenta transferred are crucial for introducing equations for amplitudes. The
three-body equation for hadron diffractive production reaction $h_1+h_3\to
h_1+h_2+h_3$ is written and solved precisely in the eikonal approach. In the
black disk regime final state scattering processes do not change the shapes of
amplitudes principally but dump amplitudes in a factor $\sim\frac 14$.
| [
{
"created": "Thu, 17 Jul 2014 07:35:19 GMT",
"version": "v1"
}
] | 2014-07-18 | [
[
"Anisovich",
"V. V.",
""
],
[
"Matveev",
"M. A.",
""
],
[
"Nikonov",
"V. A.",
""
]
] | Diffractive production is considered in the ultrahigh energy region where pomeron exchange amplitudes are transformed into black disk ones due to rescattering corrections. The corresponding corrections in hadron reactions $h_1+h_3\to h_1+h_2+h_3$ with small momenta transferred ($q^2_{1\to 1}\sim m^2/\ln^2s$, $q^2_{3\to 3}\sim m^2/\ln^2s$) are calculated in terms of the $K$-matrix technique modified for ultrahigh energies. Small values of the momenta transferred are crucial for introducing equations for amplitudes. The three-body equation for hadron diffractive production reaction $h_1+h_3\to h_1+h_2+h_3$ is written and solved precisely in the eikonal approach. In the black disk regime final state scattering processes do not change the shapes of amplitudes principally but dump amplitudes in a factor $\sim\frac 14$. |
hep-ph/9902385 | K. Matsuda | H.Nishiura, K.Matsuda, T.Fukuyama | Lepton and Quark Mass Matrices | 15pp, REVTeX, 3 Figures | Phys.Rev. D60 (1999) 013006 | 10.1103/PhysRevD.60.013006 | null | hep-ph | null | We propose a model that all quark and lepton mass matrices have the same zero
texture. Namely their (1,1), (1,3) and (3,1) components are zeros. The mass
matrices are classified into two types I and II. Type I is consistent with the
experimental data in quark sector. For lepton sector, if seesaw mechanism is
not used, Type II allows a large $\nu_\mu - \nu_\tau$ mixing angle. However,
severe compatibility with all neutrino oscillation experiments forces us to use
the seesaw mechanism. If we adopt the seesaw mechanism, it turns out that Type
I instead of II can be consistent with experimental data in the lepton sector
too.
| [
{
"created": "Thu, 18 Feb 1999 07:40:22 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Nishiura",
"H.",
""
],
[
"Matsuda",
"K.",
""
],
[
"Fukuyama",
"T.",
""
]
] | We propose a model that all quark and lepton mass matrices have the same zero texture. Namely their (1,1), (1,3) and (3,1) components are zeros. The mass matrices are classified into two types I and II. Type I is consistent with the experimental data in quark sector. For lepton sector, if seesaw mechanism is not used, Type II allows a large $\nu_\mu - \nu_\tau$ mixing angle. However, severe compatibility with all neutrino oscillation experiments forces us to use the seesaw mechanism. If we adopt the seesaw mechanism, it turns out that Type I instead of II can be consistent with experimental data in the lepton sector too. |
2112.15531 | Shi Pu | Cong Yi, Shi Pu, Jian-Hua Gao, Di-Lun Yang | Hydrodynamic helicity polarization in relativistic heavy ion collisions | 27 pages, 9 figures | null | 10.1103/PhysRevC.105.044911 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | We study helicity polarization through the (3+1) dimensional relativistic
viscous hydrodynamic models at $\sqrt{s_{NN}}=200$GeV Au+Au collisions. Similar
to the local spin polarization, we consider the helicity polarization beyond
global equilibrium and investigate the contributions induced by thermal
vorticity, shear viscous tensor, and the fluid acceleration. We find that the
local helicity polarization induced by thermal vorticity dominates over other
contributions. It also implies that in the low-energy collisions, the the fluid
vorticity as part of thermal vorticity may play the crucial role to the total
helicity polarization. Such a finding could be useful for probing the local
strength of vorticity in rotational quark gluon plasmas by measuring helicity
polarization. Our simulation confirms the strict space reversal symmetry,
whereas we also compare our numerical results with approximated relations
derived from ideal Bjorken flow. Our studies also provide a baseline for the
future investigation on local parity violation through the correlations of
helicity polarization.
| [
{
"created": "Fri, 31 Dec 2021 16:16:19 GMT",
"version": "v1"
},
{
"created": "Mon, 2 May 2022 10:16:44 GMT",
"version": "v2"
}
] | 2022-05-03 | [
[
"Yi",
"Cong",
""
],
[
"Pu",
"Shi",
""
],
[
"Gao",
"Jian-Hua",
""
],
[
"Yang",
"Di-Lun",
""
]
] | We study helicity polarization through the (3+1) dimensional relativistic viscous hydrodynamic models at $\sqrt{s_{NN}}=200$GeV Au+Au collisions. Similar to the local spin polarization, we consider the helicity polarization beyond global equilibrium and investigate the contributions induced by thermal vorticity, shear viscous tensor, and the fluid acceleration. We find that the local helicity polarization induced by thermal vorticity dominates over other contributions. It also implies that in the low-energy collisions, the the fluid vorticity as part of thermal vorticity may play the crucial role to the total helicity polarization. Such a finding could be useful for probing the local strength of vorticity in rotational quark gluon plasmas by measuring helicity polarization. Our simulation confirms the strict space reversal symmetry, whereas we also compare our numerical results with approximated relations derived from ideal Bjorken flow. Our studies also provide a baseline for the future investigation on local parity violation through the correlations of helicity polarization. |
0910.2720 | Jorge de Blas Mateo | F. del Aguila, J.A. Aguilar-Saavedra and J. de Blas | Trilepton signals: the golden channel for seesaw searches at LHC | Latex 11 pages, 7 eps figures. Contribution to the Proceedings of the
XXXIII International School of Theoretical Physics "Matter To The Deepest",
Ustron, Poland, September 11-16, 2009 | Acta Phys.Polon.B40:2901-2911,2009 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The comparison of samples with different number of charged leptons shows that
trilepton signals are the most significant ones for seesaw mediators. As
previously pointed out, this is indeed the case for scalar (type II) and
fermion (type III) triplets at LHC, which can be discovered in this channel for
masses up to 500-700 GeV and an integrated luminosity of 30 fb^-1; whereas
fermion singlets (type I) are marginally observable if there are no further new
physics near the TeV scale. However, if there are new gauge interactions at
this scale coupling to right-handed neutrinos, as in left-right models, heavy
neutrinos are observable up to masses ~ 2 TeV for new gauge boson masses up to
~ 4 TeV, as we discuss in some detail.
| [
{
"created": "Thu, 15 Oct 2009 14:37:28 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"del Aguila",
"F.",
""
],
[
"Aguilar-Saavedra",
"J. A.",
""
],
[
"de Blas",
"J.",
""
]
] | The comparison of samples with different number of charged leptons shows that trilepton signals are the most significant ones for seesaw mediators. As previously pointed out, this is indeed the case for scalar (type II) and fermion (type III) triplets at LHC, which can be discovered in this channel for masses up to 500-700 GeV and an integrated luminosity of 30 fb^-1; whereas fermion singlets (type I) are marginally observable if there are no further new physics near the TeV scale. However, if there are new gauge interactions at this scale coupling to right-handed neutrinos, as in left-right models, heavy neutrinos are observable up to masses ~ 2 TeV for new gauge boson masses up to ~ 4 TeV, as we discuss in some detail. |
hep-ph/0412396 | Raju Venugopalan | Raju Venugopalan | The Color Glass Condensate: A summary of key ideas and recent
developments | 48 pages, 22 figures, lectures at various summer schools; revised
version with corrected typos and added references | null | null | null | hep-ph nucl-ex nucl-th | null | We summarize the theory and phenomenology of the Color Glass Condensate
reviewed previously by E. Iancu and the author in hep-ph/0303204. In addition,
we discuss some of the subsequent developments in the past year both in theory
and in phenomenological applications.
| [
{
"created": "Wed, 29 Dec 2004 15:52:45 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Jan 2005 15:59:22 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Venugopalan",
"Raju",
""
]
] | We summarize the theory and phenomenology of the Color Glass Condensate reviewed previously by E. Iancu and the author in hep-ph/0303204. In addition, we discuss some of the subsequent developments in the past year both in theory and in phenomenological applications. |
1901.04441 | Roman Nikolaevich Lee | Roman N. Lee and Kirill T. Mingulov | Master integrals for two-loop $C$-odd contribution to $e^+e^-\to
\ell^+\ell^-$ process | 14 pages, 3 figures, 4 ancillary files, v2 minor stylistic changes | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate two-loop master integrals for the process of heavy lepton pair
production in $e^+e^-$ collisions. We consider the $C$-odd diagrams with three
photons in the intermediate state and evaluate the corresponding families of
the master integrals in the limit of zero electron mass. Our results for the
master integrals are directly applicable in the whole physical region
corresponding to the annihilation channel.
| [
{
"created": "Mon, 14 Jan 2019 18:15:25 GMT",
"version": "v1"
},
{
"created": "Wed, 23 Jan 2019 10:17:55 GMT",
"version": "v2"
}
] | 2019-01-24 | [
[
"Lee",
"Roman N.",
""
],
[
"Mingulov",
"Kirill T.",
""
]
] | We calculate two-loop master integrals for the process of heavy lepton pair production in $e^+e^-$ collisions. We consider the $C$-odd diagrams with three photons in the intermediate state and evaluate the corresponding families of the master integrals in the limit of zero electron mass. Our results for the master integrals are directly applicable in the whole physical region corresponding to the annihilation channel. |
hep-ph/9408205 | Fontannaz | M.Fontannaz | Probing the Photon Structure Function in Photoproduction | 11 p., LPTHE Orsay 94-65 | null | null | null | hep-ph | null | We show how the parton distributions in the photon can be accurately measured
in the photoproduction of large-pt jets at HERA. A short review is given of the
beyond Leading Logarithm formalism for the photon structure function, with a
discussion of the factorization scheme and of the non-perturbative input.
| [
{
"created": "Mon, 1 Aug 1994 18:20:55 GMT",
"version": "v1"
},
{
"created": "Thu, 4 Aug 1994 12:48:41 GMT",
"version": "v2"
}
] | 2009-09-25 | [
[
"Fontannaz",
"M.",
""
]
] | We show how the parton distributions in the photon can be accurately measured in the photoproduction of large-pt jets at HERA. A short review is given of the beyond Leading Logarithm formalism for the photon structure function, with a discussion of the factorization scheme and of the non-perturbative input. |
1904.09756 | Halil Mutuk | Halil Mutuk | Neural Network Study of Hidden-Charm Pentaquark Resonances | 10 pages, 3 figures, 7 tables, Accepted in Chinese Physics C | Chinese Phys. C 43 093103; 2019 | 10.1088/1674-1137/43/9/093103 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Very recently, LHCb experiment announced the observation of hidden-charm
pentaquark states $P_c(4312)$, $P_c(4440)$, and $P_c(4457)$ near the $ \Sigma_c
\bar{D}$ and $ \Sigma_c \bar{D}^\ast$ thresholds, respectively. In this present
work, we studied thesepentaquarks in the framework of the nonrelativistic quark
model with four types of potential. We solved 5-body Schr\"odinger equation by
using artificial neural network method and made predictions of parities for
these states which are not determined in the experiment yet. The mass of
another possible pentaquark state near the $\bar{D}^\ast \Sigma_c^\ast$ with
$J^P=5/2^-$ is also calculated.
| [
{
"created": "Mon, 22 Apr 2019 07:35:13 GMT",
"version": "v1"
},
{
"created": "Thu, 9 May 2019 07:54:17 GMT",
"version": "v2"
},
{
"created": "Tue, 9 Jul 2019 09:00:36 GMT",
"version": "v3"
}
] | 2019-09-10 | [
[
"Mutuk",
"Halil",
""
]
] | Very recently, LHCb experiment announced the observation of hidden-charm pentaquark states $P_c(4312)$, $P_c(4440)$, and $P_c(4457)$ near the $ \Sigma_c \bar{D}$ and $ \Sigma_c \bar{D}^\ast$ thresholds, respectively. In this present work, we studied thesepentaquarks in the framework of the nonrelativistic quark model with four types of potential. We solved 5-body Schr\"odinger equation by using artificial neural network method and made predictions of parities for these states which are not determined in the experiment yet. The mass of another possible pentaquark state near the $\bar{D}^\ast \Sigma_c^\ast$ with $J^P=5/2^-$ is also calculated. |
1301.6887 | Chris White | C. D. White | New insights into soft gluons and gravitons | 6 pages, 3 figures; Proceedings of 36th International Conference on
High Energy Physics, July 4-11, 2012, Melbourne, Australia | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The study of gluon radiation in QCD, in the limit of small ("soft") momentum,
remains an active research area, with a variety of phenomenological and
theoretical applications. Soft gluon emission leads to large logarithms in
perturbation theory which have to be summed up to all orders in the coupling,
and also governs the structure of infrared singularities. Recently, new
techniques and mathematical structures have been discovered, which enhance our
understanding of these all-order properties. This contribution will review a
number of key topics, including the relationship between QCD and gravity.
| [
{
"created": "Tue, 29 Jan 2013 10:31:33 GMT",
"version": "v1"
}
] | 2013-01-30 | [
[
"White",
"C. D.",
""
]
] | The study of gluon radiation in QCD, in the limit of small ("soft") momentum, remains an active research area, with a variety of phenomenological and theoretical applications. Soft gluon emission leads to large logarithms in perturbation theory which have to be summed up to all orders in the coupling, and also governs the structure of infrared singularities. Recently, new techniques and mathematical structures have been discovered, which enhance our understanding of these all-order properties. This contribution will review a number of key topics, including the relationship between QCD and gravity. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.