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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2210.03108 | Andrea Tesi | Michele Redi, Andrea Tesi | Jump Starting the Dark Sector with a Phase Transition | 25 pages, 4 figures. v2) refs added, typos fixed, minor corrections | null | 10.1007/JHEP01(2023)085 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the possibility to populate the dark sector through a phase
transition. We will consider secluded dark sectors made of gauge theories,
Randall-Sundrum scenarios and conformally coupled elementary particles. These
sectors have in common the fact that the action is approximately Weyl
invariant, implying that particle production due to time dependent background
is strongly suppressed. In particular no significant production takes place
during inflation allowing to avoid strong isocurvature constraints from CMB. As
we will show, if the scale of inflation is large compared to the dynamical mass
scale, these sectors automatically undergo a phase transition that in the
simplest cases is controlled by the Hubble parameter. If the phase transition
takes place during reheating or radiation the abundance obtained can be larger
than particle production and production from the SM plasma. For phase
transitions completing during radiation domination, the DM mass is predicted in
the range $10^8$ GeV while larger values are required for phase transitions
occurring during reheating.
| [
{
"created": "Thu, 6 Oct 2022 17:58:33 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Jan 2023 10:49:59 GMT",
"version": "v2"
}
] | 2023-02-01 | [
[
"Redi",
"Michele",
""
],
[
"Tesi",
"Andrea",
""
]
] | We study the possibility to populate the dark sector through a phase transition. We will consider secluded dark sectors made of gauge theories, Randall-Sundrum scenarios and conformally coupled elementary particles. These sectors have in common the fact that the action is approximately Weyl invariant, implying that particle production due to time dependent background is strongly suppressed. In particular no significant production takes place during inflation allowing to avoid strong isocurvature constraints from CMB. As we will show, if the scale of inflation is large compared to the dynamical mass scale, these sectors automatically undergo a phase transition that in the simplest cases is controlled by the Hubble parameter. If the phase transition takes place during reheating or radiation the abundance obtained can be larger than particle production and production from the SM plasma. For phase transitions completing during radiation domination, the DM mass is predicted in the range $10^8$ GeV while larger values are required for phase transitions occurring during reheating. |
1507.02520 | Majid Monemzadeh Dr. | N. Tazimi, M. Monemzadeh, M. R. Hadizadeh | Heavy Mesons Spectroscopy | null | Int. J. Theor. Phys. 52, 2329 ( 2013) | 10.1007/s10773-013-1516-4 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this paper, we use Martin and Coulomb-Linear potentials and solve
Lippman-Schwinger equation and then identify $b\bar{c}$ energy levels.
Moreover, we predict results for such energy levels as that of $t\bar{t}$ (in
its short half-life) which is not observed. We showed our results are
consistent with previous findings in literature. Also investigating spectrum of
eigen-values, we obtain stability interval for Yukawa-Linear potential.
| [
{
"created": "Thu, 9 Jul 2015 14:15:27 GMT",
"version": "v1"
},
{
"created": "Sat, 1 Aug 2015 20:20:39 GMT",
"version": "v2"
}
] | 2015-08-04 | [
[
"Tazimi",
"N.",
""
],
[
"Monemzadeh",
"M.",
""
],
[
"Hadizadeh",
"M. R.",
""
]
] | In this paper, we use Martin and Coulomb-Linear potentials and solve Lippman-Schwinger equation and then identify $b\bar{c}$ energy levels. Moreover, we predict results for such energy levels as that of $t\bar{t}$ (in its short half-life) which is not observed. We showed our results are consistent with previous findings in literature. Also investigating spectrum of eigen-values, we obtain stability interval for Yukawa-Linear potential. |
hep-ph/0406093 | Giancarlo D'Ambrosio | Giancarlo D'Ambrosio | CP, CPT and Rare Decays | Invited talk at Alghero DAFNE Workshop, 10-13 September 2003, 5
pages, 1 figure | null | null | DSF-13/2004 | hep-ph | null | We describe possible kaon physics goals to achieve with a high luminosity
phi-factory. We motivate the relevance to improve the present bounds on CPT
kaon physics quantities. Also, the interferometer machine phi-factory is useful
to study CP violating/conserving effects in kaon decays. Thus we investigate K
--> 3 pi amplitudes: charge asymmetries are interesting in charged kaon decays.
In the case of neutral kaon decays one can study directely K_S --> 3 pi or
interferences effects. Interference may also be used to study the CP even K_S
-->pi+ pi- pi0 and final state interactions.
| [
{
"created": "Tue, 8 Jun 2004 12:28:49 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"D'Ambrosio",
"Giancarlo",
""
]
] | We describe possible kaon physics goals to achieve with a high luminosity phi-factory. We motivate the relevance to improve the present bounds on CPT kaon physics quantities. Also, the interferometer machine phi-factory is useful to study CP violating/conserving effects in kaon decays. Thus we investigate K --> 3 pi amplitudes: charge asymmetries are interesting in charged kaon decays. In the case of neutral kaon decays one can study directely K_S --> 3 pi or interferences effects. Interference may also be used to study the CP even K_S -->pi+ pi- pi0 and final state interactions. |
hep-ph/0310096 | Sergei Shulga | A.Belkov, S.Shulga | Studies of Angular Correlations in the Decays $B^0_s\to J/\psi \phi$ by
Using the SIMUB Generator | 34 pages, 5 figures, accepted for publication in Comp. Phys. Comm. at
27/07/2003 | Comput.Phys.Commun. 156 (2004) 221-240 | 10.1016/S0010-4655(03)00465-X | null | hep-ph | null | The performance of the method of angular moments on the $\Delta\Gamma_s$
determination from analysis of untagged decays $B^0_s(t),\bar{B}^0_s(t)\to
J/\psi (\to l^+l^-) \phi (\to K^+K^-)$ is examined by using the SIMUB
generator.
The results of Monte Carlo studies with evaluation of measurement errors are
presented.
The method of angular moments gives stable results for the estimate of
$\Delta\Gamma_s$ and is found to be an efficient and flexible tool for the
quantitative investigation of the $B^0_s\to J/\psi \phi$ decay.
The statistical error of the ratio $\Delta\Gamma_s/\Gamma_s$ for values of
this ratio in the interval [0.03, 0.3] was found to be independent on this
value, being 0.015 for $10^5$ events.
| [
{
"created": "Wed, 8 Oct 2003 05:29:37 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Belkov",
"A.",
""
],
[
"Shulga",
"S.",
""
]
] | The performance of the method of angular moments on the $\Delta\Gamma_s$ determination from analysis of untagged decays $B^0_s(t),\bar{B}^0_s(t)\to J/\psi (\to l^+l^-) \phi (\to K^+K^-)$ is examined by using the SIMUB generator. The results of Monte Carlo studies with evaluation of measurement errors are presented. The method of angular moments gives stable results for the estimate of $\Delta\Gamma_s$ and is found to be an efficient and flexible tool for the quantitative investigation of the $B^0_s\to J/\psi \phi$ decay. The statistical error of the ratio $\Delta\Gamma_s/\Gamma_s$ for values of this ratio in the interval [0.03, 0.3] was found to be independent on this value, being 0.015 for $10^5$ events. |
1007.4449 | Jeppe R. Andersen | Jeppe R. Andersen (CERN) and Jennifer M. Smillie (UCL) | High Energy Description of Processes with Multiple Hard Jets | Talk presented at Loop and Legs in Quantum Field Theory, W\"{o}rlitz,
Germany, 25th-30th April 2010 | Nucl.Phys.Proc.Suppl.205-206:205-210,2010 | 10.1016/j.nuclphysbps.2010.08.044 | CERN-PH-TH/2010-167 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | High Energy Jets (HEJ) is a new framework for approximating the all-order
perturbative corrections to multi-jet processes, with a focus on the hard,
wide-angle QCD emissions, which underpins the perturbative description of hard
jets. In this contribution we review the basic concepts of HEJ, and present
some new predictions for observables in dijet-production, and for W-boson
production in association with at least 3 jets.
| [
{
"created": "Mon, 26 Jul 2010 13:20:19 GMT",
"version": "v1"
}
] | 2010-12-13 | [
[
"Andersen",
"Jeppe R.",
"",
"CERN"
],
[
"Smillie",
"Jennifer M.",
"",
"UCL"
]
] | High Energy Jets (HEJ) is a new framework for approximating the all-order perturbative corrections to multi-jet processes, with a focus on the hard, wide-angle QCD emissions, which underpins the perturbative description of hard jets. In this contribution we review the basic concepts of HEJ, and present some new predictions for observables in dijet-production, and for W-boson production in association with at least 3 jets. |
hep-ph/0011147 | Jisuke Kubo | Jisuke Kubo and Masanori Nunami | Extra dimensions prefer large $\tan\beta$ | 26 pages, TeX, 7 figures | Phys.Rev. D63 (2001) 116011 | 10.1103/PhysRevD.63.116011 | KANAZAWA-00-11 | hep-ph | null | Assuming that the recent result obtained from the Monte Carlo simulations on
the nonperturbative existence of the pure SU(2) Yang-Mills theory in five
dimensions can be applied to a more general class of higher-dimensional gauge
theories, we derive the conditions imposed by the nontriviality requirement on
the theories. We find that the supersymmetric grand unified theories with extra
dimensions prefer a large value ($\gsim 2$) of $\tan\beta$ of the minimal
supersymmetric standard model, in accord with today's possible observation of
the Higgs particle at LEP2.
| [
{
"created": "Fri, 10 Nov 2000 09:49:40 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Nov 2000 08:50:25 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kubo",
"Jisuke",
""
],
[
"Nunami",
"Masanori",
""
]
] | Assuming that the recent result obtained from the Monte Carlo simulations on the nonperturbative existence of the pure SU(2) Yang-Mills theory in five dimensions can be applied to a more general class of higher-dimensional gauge theories, we derive the conditions imposed by the nontriviality requirement on the theories. We find that the supersymmetric grand unified theories with extra dimensions prefer a large value ($\gsim 2$) of $\tan\beta$ of the minimal supersymmetric standard model, in accord with today's possible observation of the Higgs particle at LEP2. |
1210.6975 | Franck Sabati\'e | Peter Kroll, Herv\'e Moutarde, Franck Sabati\'e | From hard exclusive meson electroproduction to deeply virtual Compton
scattering | 37 pages, 12 figures v2 : fixed typos, updated to future published
version (EPJC). v3 : fixed typo in Eq. (59) | Eur. Phys. J. C (2013) 73:2278 | 10.1140/epjc/s10052-013-2278-0 | IRFU-12-174; WUB/12-22 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We systematically evaluate observables for hard exclusive electroproduction
of real photons and compare them to experiment using a set of Generalized
Parton Distributions (GPDs) whose parameters are constrained by Deeply Virtual
Meson Production data, nucleon form factors and parton distributions. The
Deeply Virtual Compton Scattering amplitudes are calculated to leading-twist
accuracy and leading order in QCD perturbation theory while the leptonic tensor
is treated exactly, without any approximation. This study constitutes a check
of the universality of the GPDs. We summarize all relevant details on the
parametrizations of the GPDs and describe its use in the handbag approach of
the aforementioned hard scattering processes. We observe a good agreement
between predictions and measurements of deeply virtual Compton scattering on a
wide kinematic range, including most data from H1, ZEUS, HERMES, Hall A and
CLAS collaborations for unpolarized and polarized targets when available. We
also give predictions relevant for future experiments at COMPASS and JLab after
the 12 GeV upgrade.
| [
{
"created": "Thu, 25 Oct 2012 19:58:47 GMT",
"version": "v1"
},
{
"created": "Wed, 2 Jan 2013 13:20:48 GMT",
"version": "v2"
},
{
"created": "Tue, 23 Apr 2013 14:55:33 GMT",
"version": "v3"
}
] | 2013-04-24 | [
[
"Kroll",
"Peter",
""
],
[
"Moutarde",
"Hervé",
""
],
[
"Sabatié",
"Franck",
""
]
] | We systematically evaluate observables for hard exclusive electroproduction of real photons and compare them to experiment using a set of Generalized Parton Distributions (GPDs) whose parameters are constrained by Deeply Virtual Meson Production data, nucleon form factors and parton distributions. The Deeply Virtual Compton Scattering amplitudes are calculated to leading-twist accuracy and leading order in QCD perturbation theory while the leptonic tensor is treated exactly, without any approximation. This study constitutes a check of the universality of the GPDs. We summarize all relevant details on the parametrizations of the GPDs and describe its use in the handbag approach of the aforementioned hard scattering processes. We observe a good agreement between predictions and measurements of deeply virtual Compton scattering on a wide kinematic range, including most data from H1, ZEUS, HERMES, Hall A and CLAS collaborations for unpolarized and polarized targets when available. We also give predictions relevant for future experiments at COMPASS and JLab after the 12 GeV upgrade. |
hep-ph/9711488 | Daniel Boer | D. Boer, R. Jakob, P.J. Mulders | Leading asymmetries in two-hadron production in e^+e^- annihilation at
the Z pole | 8 pages, Revtex, 2 Postscript figures, uses epsf.sty. Some typos
corrected, minor clarifying changes, one reference added, including a comment
at the end | Phys.Lett.B424:143-151,1998 | 10.1016/S0370-2693(98)00136-1 | NIKHEF 97-046, VUTH 97-19, FNT/T-97/14 | hep-ph | null | We present the leading unpolarized and single spin asymmetries in inclusive
two-hadron production in electron-positron annihilation at the Z pole. The
azimuthal dependence in the unpolarized differential cross section of almost
back-to-back hadrons is a leading cos(2 phi) asymmetry, which arises solely due
to the intrinsic transverse momenta of the quarks. An extensive discussion on
how to measure this asymmetry and the accompanying time-reversal odd
fragmentation functions is given. A simple estimate indicates that the
asymmetry could be of the order of a percent.
| [
{
"created": "Thu, 27 Nov 1997 09:37:16 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Jan 1998 12:13:23 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Boer",
"D.",
""
],
[
"Jakob",
"R.",
""
],
[
"Mulders",
"P. J.",
""
]
] | We present the leading unpolarized and single spin asymmetries in inclusive two-hadron production in electron-positron annihilation at the Z pole. The azimuthal dependence in the unpolarized differential cross section of almost back-to-back hadrons is a leading cos(2 phi) asymmetry, which arises solely due to the intrinsic transverse momenta of the quarks. An extensive discussion on how to measure this asymmetry and the accompanying time-reversal odd fragmentation functions is given. A simple estimate indicates that the asymmetry could be of the order of a percent. |
hep-ph/9610312 | Terry Goldman | L. S. Kisslinger (CMU), T. Goldman (LANL) and Z. Li (CMU) | QED Penguin Contributions To Isospin Splittings of Heavy-Light Quark
Systems | 9 pages, latex, 2 figures | Phys.Lett.B416:263-267,1998 | 10.1016/S0370-2693(97)01321-X | null | hep-ph nucl-th | null | Recent experiments show that the isospin-violating mass splitting of the B
mesons is very small, but the best fits with a QCD sum rule analysis give a
splitting of at least 1.0 MeV. The isospin-violating mass splittings of the
charmed mesons, on the other hand, are in agreement with experiment. In this
letter we show that the inclusion of 2$^{nd}$ kind QED penguin diagrams can
account for this discrepancy within the errors in the QCD sum rule method.
| [
{
"created": "Thu, 10 Oct 1996 15:29:38 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Kisslinger",
"L. S.",
"",
"CMU"
],
[
"Goldman",
"T.",
"",
"LANL"
],
[
"Li",
"Z.",
"",
"CMU"
]
] | Recent experiments show that the isospin-violating mass splitting of the B mesons is very small, but the best fits with a QCD sum rule analysis give a splitting of at least 1.0 MeV. The isospin-violating mass splittings of the charmed mesons, on the other hand, are in agreement with experiment. In this letter we show that the inclusion of 2$^{nd}$ kind QED penguin diagrams can account for this discrepancy within the errors in the QCD sum rule method. |
1806.04488 | Shankha Banerjee | Shankha Banerjee, Genevi\`eve B\'elanger, Avirup Ghosh and Biswarup
Mukhopadhyaya | Long-lived stau, sneutrino dark matter and right-slepton spectrum | v2: 25 pages, 4 figures and 6 tables; Freeze-in contribution to relic
included; detection prospects at MoEDAL included; text expanded; references
added; conclusions unchanged; version accepted for publication in JHEP | JHEP 1809 (2018) 143 | 10.1007/JHEP09(2018)143 | IPPP/18/44, LAPTH-021/18, HRI-RECAPP-2018-004 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The minimal supersymmetric (SUSY) standard model (MSSM) augmented by right
chiral sneutrinos may lead to one such sneutrino serving as the lightest
supersymmetric particle and a non-thermal dark matter candidate, especially if
neutrinos have Dirac masses only. In such cases, if the lightest MSSM particle
is a stau, the signal of SUSY at the LHC consists in stable charged tracks
which are distinguishable from backgrounds through their time delay between the
inner tracker and the muon chamber. We show how to determine in such scenarios
the mass hierarchy between the lightest neutralino and right sleptons of the
first two families. The techniques of neutralino reconstruction, developed in
earlier works, are combined with the endpoint of the variable $M_{T2}$ in smuon
(selectron) decays for this purpose. We show that one can thus determine the
mass hierarchy for smuons (selectrons) and neutralinos up to 1 TeV, to the
level of 5-10\%.
| [
{
"created": "Tue, 12 Jun 2018 13:16:25 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Sep 2018 19:19:17 GMT",
"version": "v2"
}
] | 2018-09-27 | [
[
"Banerjee",
"Shankha",
""
],
[
"Bélanger",
"Geneviève",
""
],
[
"Ghosh",
"Avirup",
""
],
[
"Mukhopadhyaya",
"Biswarup",
""
]
] | The minimal supersymmetric (SUSY) standard model (MSSM) augmented by right chiral sneutrinos may lead to one such sneutrino serving as the lightest supersymmetric particle and a non-thermal dark matter candidate, especially if neutrinos have Dirac masses only. In such cases, if the lightest MSSM particle is a stau, the signal of SUSY at the LHC consists in stable charged tracks which are distinguishable from backgrounds through their time delay between the inner tracker and the muon chamber. We show how to determine in such scenarios the mass hierarchy between the lightest neutralino and right sleptons of the first two families. The techniques of neutralino reconstruction, developed in earlier works, are combined with the endpoint of the variable $M_{T2}$ in smuon (selectron) decays for this purpose. We show that one can thus determine the mass hierarchy for smuons (selectrons) and neutralinos up to 1 TeV, to the level of 5-10\%. |
hep-ph/9708336 | Mariana Kirchbach | M. Kirchbach | On the Parity Degeneracy of Baryons | 9 pages, LaTex, 1 figure; published in Mod.Phys.Lett. A12 (1997)
2373; minor misprints corrected, no statement changes | Mod.Phys.Lett. A12 (1997) 2373-2386 | 10.1142/S0217732397002466 | null | hep-ph nucl-th | null | The gross features of the observed baryon excitation spectrum below 2 GeV are
well explained if the spectrum generating algebra of its intrinsic orbital
angular momentum states is o(4)*su(2)_I. The spins of the resonances are
obtained through the coupling of a Lorentz bi-spinor (1/2,0)+ (0,1/ 2) to a
multiplet of the type (j,j) in its O(4)/O(3) reduction. The parities of the
resonances follow from those of the O(3) members of the (j,j) multiplets. In
this way relativistic SL(2,C) representations are constructed. For example, the
first S11, P11, and D13 states with masses around 1500 MeV fit into the (1/2,
1/2)* [(1/2,0)+(0,1/2)] representation. The observed parities of the resonances
correspond to natural parities of the (1/2,1/2) states. The second P11, S11,
D13- together with the first P13, F15, D15, and (a predicted) F17 -resonances,
centered around 1700 MeV, are organized into the (3/2,3/2)*[(1/2,0)+(0,1/2)]
representation. I argue that the members of the (3/2,3/2) multiplet carry
unnatural parities and that in this region chiral symmetry is restored. In the
N(939)- N(1650) transition the chiral symmetry mode is changed, and therefore,
a chiral phase transition is predicted to take place.
| [
{
"created": "Wed, 13 Aug 1997 10:32:15 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Dec 1997 13:39:41 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Kirchbach",
"M.",
""
]
] | The gross features of the observed baryon excitation spectrum below 2 GeV are well explained if the spectrum generating algebra of its intrinsic orbital angular momentum states is o(4)*su(2)_I. The spins of the resonances are obtained through the coupling of a Lorentz bi-spinor (1/2,0)+ (0,1/ 2) to a multiplet of the type (j,j) in its O(4)/O(3) reduction. The parities of the resonances follow from those of the O(3) members of the (j,j) multiplets. In this way relativistic SL(2,C) representations are constructed. For example, the first S11, P11, and D13 states with masses around 1500 MeV fit into the (1/2, 1/2)* [(1/2,0)+(0,1/2)] representation. The observed parities of the resonances correspond to natural parities of the (1/2,1/2) states. The second P11, S11, D13- together with the first P13, F15, D15, and (a predicted) F17 -resonances, centered around 1700 MeV, are organized into the (3/2,3/2)*[(1/2,0)+(0,1/2)] representation. I argue that the members of the (3/2,3/2) multiplet carry unnatural parities and that in this region chiral symmetry is restored. In the N(939)- N(1650) transition the chiral symmetry mode is changed, and therefore, a chiral phase transition is predicted to take place. |
hep-ph/0701093 | David Rainwater | D. Rainwater and T. Tait | Testing Grand Unification at the (S)LHC | 12 pages, 7 embedded ps figures, submitted to PRD | Phys.Rev.D75:115014,2007 | 10.1103/PhysRevD.75.115014 | null | hep-ph | null | We examine the possibility of measuring the three gauge couplings at high
scales at the LHC, in order to see the first steps as they run toward Grand
Unification at much higher energies. Using the MSSM with sparticle masses of
several hundred GeV as an example of a theory in which the couplings do unify
at very high energies, we find that the processes pp->lv, pp->l+l- and
pp->gamma+j can be useful to discriminate the SM from the MSSM with masses at
the few hundred GeV scale, and determine that the couplings are converging at
better than the SM prediction toward the GUT scale. Such measurements
indirectly probe the existence of lower mass states, charged under the SM gauge
groups, but which may be difficult to produce directly or extract from
backgrounds at the LHC.
| [
{
"created": "Thu, 11 Jan 2007 23:30:50 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Rainwater",
"D.",
""
],
[
"Tait",
"T.",
""
]
] | We examine the possibility of measuring the three gauge couplings at high scales at the LHC, in order to see the first steps as they run toward Grand Unification at much higher energies. Using the MSSM with sparticle masses of several hundred GeV as an example of a theory in which the couplings do unify at very high energies, we find that the processes pp->lv, pp->l+l- and pp->gamma+j can be useful to discriminate the SM from the MSSM with masses at the few hundred GeV scale, and determine that the couplings are converging at better than the SM prediction toward the GUT scale. Such measurements indirectly probe the existence of lower mass states, charged under the SM gauge groups, but which may be difficult to produce directly or extract from backgrounds at the LHC. |
2107.12266 | Amir Fariborz | Amir H. Fariborz and Mars Lyukova | Spinless mesons and glueballs mixing patterns in SU(3) flavor limit | 35 pages, 19 figures. arXiv admin note: text overlap with
arXiv:1810.10624 | null | 10.1016/j.nuclphysa.2021.122286 | null | hep-ph hep-ex hep-lat nucl-ex nucl-th | http://creativecommons.org/licenses/by-nc-nd/4.0/ | We present a detailed study of the interactions among scalar and pseudoscalar
mesons and glueballs within the framework of the generalized linear sigma model
in the SU(3) flavor limit. The basis of our approach is to develop a global
understanding of light scalar and pseudoscalar mesons (up to around 2 GeV) and
thereby explore the underlying mixings among composite quark matter fields and
glueballs. The chiral sector of the Lagrangian is formulated in terms of two
chiral nonets representing quark-antiquarks and tetraquarks (in the leading
order, this sector contains terms with eight or fewer number of quak or
antiquark lines). The Lagrangian also contains a sector that represents scalar
and pseudoscalar glueballs and their interactions with the matter chiral
fields, in a manner that the axial and trace anomalies of QCD are exactly
realized. In this construct, the model has two scalar octets and two
pdeudoscalar octets (each a linear combination of two- and four-quark
components), as well as three scalar SU(3) singlets and three pseudoscalar
SU(3) singlets (each a linear combination of two- and four-quark components as
well as a glueball component). With the inputs of the experimental masses of
$a_0(980)$, $a_0(1450)$, and the masses of $\pi(137)$, $\pi(1300)$ and their
decay constants, we perform an extensive numerical simulation to determine the
boundaries of the parameter space of the model. We further incorporate
experimental data on the mass spectrum of eta states as well as on several
decay widths and decay ratios of $f_0$ states to zoom in on the parameter space
and make predictions for the substructure of pseudoscalar and scalar SU(3)
octets and singlets as well as for the pseudoscalar and scalar glueball masses.
We find the scalar and pseudoscalar glueball masses around 1.6 and 2.0 GeV,
respectively.
| [
{
"created": "Mon, 26 Jul 2021 15:16:27 GMT",
"version": "v1"
}
] | 2021-08-25 | [
[
"Fariborz",
"Amir H.",
""
],
[
"Lyukova",
"Mars",
""
]
] | We present a detailed study of the interactions among scalar and pseudoscalar mesons and glueballs within the framework of the generalized linear sigma model in the SU(3) flavor limit. The basis of our approach is to develop a global understanding of light scalar and pseudoscalar mesons (up to around 2 GeV) and thereby explore the underlying mixings among composite quark matter fields and glueballs. The chiral sector of the Lagrangian is formulated in terms of two chiral nonets representing quark-antiquarks and tetraquarks (in the leading order, this sector contains terms with eight or fewer number of quak or antiquark lines). The Lagrangian also contains a sector that represents scalar and pseudoscalar glueballs and their interactions with the matter chiral fields, in a manner that the axial and trace anomalies of QCD are exactly realized. In this construct, the model has two scalar octets and two pdeudoscalar octets (each a linear combination of two- and four-quark components), as well as three scalar SU(3) singlets and three pseudoscalar SU(3) singlets (each a linear combination of two- and four-quark components as well as a glueball component). With the inputs of the experimental masses of $a_0(980)$, $a_0(1450)$, and the masses of $\pi(137)$, $\pi(1300)$ and their decay constants, we perform an extensive numerical simulation to determine the boundaries of the parameter space of the model. We further incorporate experimental data on the mass spectrum of eta states as well as on several decay widths and decay ratios of $f_0$ states to zoom in on the parameter space and make predictions for the substructure of pseudoscalar and scalar SU(3) octets and singlets as well as for the pseudoscalar and scalar glueball masses. We find the scalar and pseudoscalar glueball masses around 1.6 and 2.0 GeV, respectively. |
hep-ph/9809327 | null | U. Baur (SUNY Buffalo) | Electroweak Radiative Corrections to W Boson Production at the Tevatron | 6 pages, LaTeX, uses ltwol2e_ub style file (included), 3 postscript
figures, talk given at ICHEP98 | null | null | UB-HET-98-02 | hep-ph | null | We discuss the O(alpha) electroweak radiative corrections to W boson
production at the Tevatron and their effect on the W boson mass extracted by
experiment. The results of a new calculation of the O(alpha) corrections are
presented and compared with those of a previous calculation. We also briefly
discuss the O(alpha) corrections to Z boson production at the Tevatron and
two-photon radiation in W and Z events.
| [
{
"created": "Thu, 10 Sep 1998 20:27:20 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Baur",
"U.",
"",
"SUNY Buffalo"
]
] | We discuss the O(alpha) electroweak radiative corrections to W boson production at the Tevatron and their effect on the W boson mass extracted by experiment. The results of a new calculation of the O(alpha) corrections are presented and compared with those of a previous calculation. We also briefly discuss the O(alpha) corrections to Z boson production at the Tevatron and two-photon radiation in W and Z events. |
hep-ph/0311036 | Jusak Tandean | Jusak Tandean | New Physics and CP Violation in Hyperon Nonleptonic Decays | 12 pages, 2 figures | Phys.Rev. D69 (2004) 076008 | 10.1103/PhysRevD.69.076008 | SMU-HEP-03-11 | hep-ph hep-ex | null | The sum of the CP-violating asymmetries A(Lambda_-^0) and A(Xi_-^-) in
hyperon nonleptonic decays is presently being measured by the E871 experiment.
We evaluate contributions to the asymmetries induced by chromomagnetic-penguin
operators, whose coefficients can be enhanced in certain models of new physics.
Incorporating recent information on the strong phases in Xi->Lambda pi decay,
we show that new-physics contributions to the two asymmetries can be
comparable. We explore how the upcoming results of E871 may constrain the
coefficients of the operators. We find that its preliminary measurement is
already better than the epsilon parameter of K-Kbar mixing in bounding the
parity-conserving contributions.
| [
{
"created": "Tue, 4 Nov 2003 20:53:53 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Tandean",
"Jusak",
""
]
] | The sum of the CP-violating asymmetries A(Lambda_-^0) and A(Xi_-^-) in hyperon nonleptonic decays is presently being measured by the E871 experiment. We evaluate contributions to the asymmetries induced by chromomagnetic-penguin operators, whose coefficients can be enhanced in certain models of new physics. Incorporating recent information on the strong phases in Xi->Lambda pi decay, we show that new-physics contributions to the two asymmetries can be comparable. We explore how the upcoming results of E871 may constrain the coefficients of the operators. We find that its preliminary measurement is already better than the epsilon parameter of K-Kbar mixing in bounding the parity-conserving contributions. |
1801.02652 | Xiaojun Yao | Xiaojun Yao and Berndt M\"uller | Doubly charmed baryon production in heavy ion collisions | 9 pages, 3 figures, add a discussion of productions of other doubly
heavy baryons and doubly heavy tetraquarks; add a discussion on diquark free
energy on the lattice; add a comment on experimental feasibility; published
version | Phys. Rev. D 97, 074003 (2018) | 10.1103/PhysRevD.97.074003 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We give an estimate of $\Xi_{cc}^{++}$ production rate and transverse
momentum spectra in relativistic heavy ion collisions. We use Boltzmann
transport equations to describe the dynamical evolution of charm quarks and
diquarks inside quark-gluon plasma. In-medium formation and dissociation rates
of charm diquarks are calculated from potential non-relativistic QCD for the
diquark sector. We solve the transport equations by Monte Carlo simulations.
For $2.76$ TeV Pb-Pb collisions with $0-10\%$ centrality, the number of
$\Xi_{cc}^{++}$ produced in the transverse momentum range $0-5$ GeV and
rapidity from $-1$ to $1$ is roughly $0.02$ per collision. We repeat the
calculation with a melting temperature $250$ MeV above which no diquarks can be
formed. The number of $\Xi_{cc}^{++}$ produced in the same kinematic region is
about $0.0125$ per collision. We discuss how to study diquarks at finite
temperature on a lattice and construct the anti-triplet free energy in a gauge
invariant but path dependent way. We also comment on extensions of the
calculation to other doubly heavy baryons and doubly heavy tetraquarks and the
feasibility of experimental measurements.
| [
{
"created": "Mon, 8 Jan 2018 19:24:45 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Jan 2018 21:02:47 GMT",
"version": "v2"
},
{
"created": "Wed, 24 Jan 2018 16:03:19 GMT",
"version": "v3"
},
{
"created": "Mon, 12 Mar 2018 00:29:07 GMT",
"version": "v4"
},
{
"cr... | 2018-04-05 | [
[
"Yao",
"Xiaojun",
""
],
[
"Müller",
"Berndt",
""
]
] | We give an estimate of $\Xi_{cc}^{++}$ production rate and transverse momentum spectra in relativistic heavy ion collisions. We use Boltzmann transport equations to describe the dynamical evolution of charm quarks and diquarks inside quark-gluon plasma. In-medium formation and dissociation rates of charm diquarks are calculated from potential non-relativistic QCD for the diquark sector. We solve the transport equations by Monte Carlo simulations. For $2.76$ TeV Pb-Pb collisions with $0-10\%$ centrality, the number of $\Xi_{cc}^{++}$ produced in the transverse momentum range $0-5$ GeV and rapidity from $-1$ to $1$ is roughly $0.02$ per collision. We repeat the calculation with a melting temperature $250$ MeV above which no diquarks can be formed. The number of $\Xi_{cc}^{++}$ produced in the same kinematic region is about $0.0125$ per collision. We discuss how to study diquarks at finite temperature on a lattice and construct the anti-triplet free energy in a gauge invariant but path dependent way. We also comment on extensions of the calculation to other doubly heavy baryons and doubly heavy tetraquarks and the feasibility of experimental measurements. |
1402.6287 | Alessandro Strumia | Andrea De Simone, Gian Francesco Giudice, Alessandro Strumia | Benchmarks for Dark Matter Searches at the LHC | 22 pages. v3: references added, factors of 2 fixed in section 2.1 | JHEP 1406:081,2014 | 10.1007/JHEP06(2014)081 | CERN-PH-TH/2014-008, SISSA 01/2014/FISI | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose some scenarios to pursue dark matter searches at the LHC in a
fairly model-independent way. The first benchmark case is dark matter
co-annihilations with coloured particles (gluinos or squarks being special
examples). We determine the masses that lead to the correct thermal relic
density including, for the first time, strong Sommerfeld corrections taking
into account colour decomposition. In the second benchmark case we consider
dark matter that couples to SM particles via the Z or the Higgs. We determine
the couplings allowed by present experiments and discuss future prospects.
Finally we present the case of dark matter that freezes out via decays and
apply our results to invisible Z and Higgs decays.
| [
{
"created": "Tue, 25 Feb 2014 19:33:38 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Feb 2014 08:32:54 GMT",
"version": "v2"
},
{
"created": "Wed, 30 Apr 2014 19:42:18 GMT",
"version": "v3"
}
] | 2014-06-24 | [
[
"De Simone",
"Andrea",
""
],
[
"Giudice",
"Gian Francesco",
""
],
[
"Strumia",
"Alessandro",
""
]
] | We propose some scenarios to pursue dark matter searches at the LHC in a fairly model-independent way. The first benchmark case is dark matter co-annihilations with coloured particles (gluinos or squarks being special examples). We determine the masses that lead to the correct thermal relic density including, for the first time, strong Sommerfeld corrections taking into account colour decomposition. In the second benchmark case we consider dark matter that couples to SM particles via the Z or the Higgs. We determine the couplings allowed by present experiments and discuss future prospects. Finally we present the case of dark matter that freezes out via decays and apply our results to invisible Z and Higgs decays. |
hep-ph/9508379 | Mikko Laine | K.Kajantie, M.Laine, K.Rummukainen and M.Shaposhnikov | Generic Rules for High Temperature Dimensional Reduction and Their
Application to the Standard Model | 44 pages of LaTeX, 9 figures as uuencoded compressed postscript | Nucl.Phys.B458:90-136,1996 | 10.1016/0550-3213(95)00549-8 | CERN-TH/95-226, HU-TFT-95-50, IUHET-312 | hep-ph | null | We formulate the rules for dimensional reduction of a generic finite
temperature gauge theory to a simpler three-dimensional effective bosonic
theory in terms of a matching of Green's functions in the full and the
effective theory, and present a computation of a generic set of 1- and 2-loop
graphs needed for the application of these rules. As a concrete application we
determine the explicit mapping of the physical parameters of the standard
electroweak theory to a three-dimensional SU(2)xU(1) gauge-Higgs theory. We
argue that this three-dimensional theory has a universal character and appears
as an effective theory for many extensions of the Standard Model.
| [
{
"created": "Sun, 27 Aug 1995 17:00:19 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Kajantie",
"K.",
""
],
[
"Laine",
"M.",
""
],
[
"Rummukainen",
"K.",
""
],
[
"Shaposhnikov",
"M.",
""
]
] | We formulate the rules for dimensional reduction of a generic finite temperature gauge theory to a simpler three-dimensional effective bosonic theory in terms of a matching of Green's functions in the full and the effective theory, and present a computation of a generic set of 1- and 2-loop graphs needed for the application of these rules. As a concrete application we determine the explicit mapping of the physical parameters of the standard electroweak theory to a three-dimensional SU(2)xU(1) gauge-Higgs theory. We argue that this three-dimensional theory has a universal character and appears as an effective theory for many extensions of the Standard Model. |
1503.04140 | Andrea Giuseppe Di Iura | Andrea Di Iura, Claudia Hagedorn, Davide Meloni | Lepton mixing from the interplay of the alternating group A5 and CP | 1+26 pages, 1 table, 2 figures; v2: matches version published in JHEP | null | 10.1007/JHEP08(2015)037 | RM3-TH/15-1 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Assuming three generations of Majorana neutrinos, we study the different
mixing patterns that arise from the non-trivial breaking of the flavor group A5
and CP to the residual symmetries Z3, Z5 or Z2 x Z2 in the charged lepton and
to Z2 x CP in the neutrino sector. All patterns contain only one free parameter
theta and thus mixing angles as well as the Dirac and the two Majorana phases
are strongly correlated. We perform an analytical and a numerical study of all
possible mixing patterns. It turns out that only four patterns can describe the
experimentally measured values of the mixing angles for a particular choice of
theta well. All of them predict trivial Majorana phases, while the Dirac phase
delta is maximal for two patterns and trivial for the two remaining ones. If
delta is maximal, also the atmospheric mixing angle is fixed to be maximal.
| [
{
"created": "Fri, 13 Mar 2015 16:50:03 GMT",
"version": "v1"
},
{
"created": "Mon, 31 Aug 2015 19:21:46 GMT",
"version": "v2"
}
] | 2015-09-30 | [
[
"Di Iura",
"Andrea",
""
],
[
"Hagedorn",
"Claudia",
""
],
[
"Meloni",
"Davide",
""
]
] | Assuming three generations of Majorana neutrinos, we study the different mixing patterns that arise from the non-trivial breaking of the flavor group A5 and CP to the residual symmetries Z3, Z5 or Z2 x Z2 in the charged lepton and to Z2 x CP in the neutrino sector. All patterns contain only one free parameter theta and thus mixing angles as well as the Dirac and the two Majorana phases are strongly correlated. We perform an analytical and a numerical study of all possible mixing patterns. It turns out that only four patterns can describe the experimentally measured values of the mixing angles for a particular choice of theta well. All of them predict trivial Majorana phases, while the Dirac phase delta is maximal for two patterns and trivial for the two remaining ones. If delta is maximal, also the atmospheric mixing angle is fixed to be maximal. |
hep-ph/0202166 | Sven Heinemeyer | M. Frank, S. Heinemeyer, W. Hollik, G. Weiglein | FeynHiggs1.2: Hybrid MSbar/on-shell Renormalization for the CP-even
Higgs Boson Sector in the MSSM | 4 pages, 3 figures, contribution to the workshop "Physics at TeV
Colliders", Les Houches, France May 2001 | null | null | BNL-HET-01/38, DCPT/02/22, IPPP/02/10, KA-TP-2-2002 | hep-ph | null | An updated version is presented of the Fortran code FeynHiggs for the
evaluation of the neutral CP-even Higgs sector masses and mixing angles. It
differs from the previous version by a modification of the renormalization
scheme concerning the treatment of subleading terms at the one-loop level; the
two-loop corrections, for which the leading contributions of O(alpha_t alphas)
and O(alpha_t^2) are implemented, are not affected by the modified
renormalization prescription. Besides stabilizing the Higgs mass calculations
and avoiding unphysically large threshold effects, the mass of the lightest
MSSM Higgs boson, m_h, is increased by 1-2 GeV for most parts of the MSSM
parameter space.
| [
{
"created": "Sat, 16 Feb 2002 22:07:20 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Frank",
"M.",
""
],
[
"Heinemeyer",
"S.",
""
],
[
"Hollik",
"W.",
""
],
[
"Weiglein",
"G.",
""
]
] | An updated version is presented of the Fortran code FeynHiggs for the evaluation of the neutral CP-even Higgs sector masses and mixing angles. It differs from the previous version by a modification of the renormalization scheme concerning the treatment of subleading terms at the one-loop level; the two-loop corrections, for which the leading contributions of O(alpha_t alphas) and O(alpha_t^2) are implemented, are not affected by the modified renormalization prescription. Besides stabilizing the Higgs mass calculations and avoiding unphysically large threshold effects, the mass of the lightest MSSM Higgs boson, m_h, is increased by 1-2 GeV for most parts of the MSSM parameter space. |
1708.01889 | Ai-Jun Ma | Ai-Jun Ma, Ya Li, Wen-Fei Wang, Zhen-Jun Xiao | Quasi-two-body decays $B_{(s)} \to D (\rho(1450),\rho(1700)) \to D \pi
\pi$ in the perturbative QCD factorization approach | 8 pages, 1 figure and 3 tables. Some modifications, matching the
published version | Phys. Rev. D 96, 093011 (2017) | 10.1103/PhysRevD.96.093011 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By employing a framework for the quasi-two-body decays in the perturbative
QCD (PQCD) factorization approach, we calculate the branching ratios of the
decays $B_{(s)} \to D (\rho(1450),\rho(1700))\to D \pi \pi$ with $D=(D_{(s)},
\bar{D}_{(s)})$. The pion vector form factor $F_\pi$, acquired from a {\it
BABAR} Collaboration analysis of $e^+ e^- \to \pi^+ \pi^-(\gamma)$ data, is
involved in the two-pion distribution amplitudes $\Phi^{I=1}_{\pi\pi}$. The
PQCD predictions for the branching ratios of the considered quasi-two-body
decays are in the range of $10^{-10} \sim 10^{-4}$. The PQCD predictions for
${\cal B}(B^0\to \bar{D}^0 (\rho^0(1450),\rho^0(1700)) \to \bar{D}^0
\pi^+\pi^-)$ agree well with the measured values as reported by LHCb if one
takes still large theoretical errors into account. Unlike the traditional way
of the PQCD approach, one can extract the decay rates for the two-body decays
$B_{(s)} \to D (\rho(1450),\rho(1700))$ from the results of the corresponding
quasi-two-body decays. The PQCD predictions for ${\cal B}(B_{(s)} \to D
\rho(1450))$ and ${\cal B}(B_{(s)} \to D \rho(770))$ are similar in magnitude:
an interesting relation to be tested by future experimental measurements.
| [
{
"created": "Sun, 6 Aug 2017 13:38:11 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Nov 2017 03:29:22 GMT",
"version": "v2"
}
] | 2017-11-30 | [
[
"Ma",
"Ai-Jun",
""
],
[
"Li",
"Ya",
""
],
[
"Wang",
"Wen-Fei",
""
],
[
"Xiao",
"Zhen-Jun",
""
]
] | By employing a framework for the quasi-two-body decays in the perturbative QCD (PQCD) factorization approach, we calculate the branching ratios of the decays $B_{(s)} \to D (\rho(1450),\rho(1700))\to D \pi \pi$ with $D=(D_{(s)}, \bar{D}_{(s)})$. The pion vector form factor $F_\pi$, acquired from a {\it BABAR} Collaboration analysis of $e^+ e^- \to \pi^+ \pi^-(\gamma)$ data, is involved in the two-pion distribution amplitudes $\Phi^{I=1}_{\pi\pi}$. The PQCD predictions for the branching ratios of the considered quasi-two-body decays are in the range of $10^{-10} \sim 10^{-4}$. The PQCD predictions for ${\cal B}(B^0\to \bar{D}^0 (\rho^0(1450),\rho^0(1700)) \to \bar{D}^0 \pi^+\pi^-)$ agree well with the measured values as reported by LHCb if one takes still large theoretical errors into account. Unlike the traditional way of the PQCD approach, one can extract the decay rates for the two-body decays $B_{(s)} \to D (\rho(1450),\rho(1700))$ from the results of the corresponding quasi-two-body decays. The PQCD predictions for ${\cal B}(B_{(s)} \to D \rho(1450))$ and ${\cal B}(B_{(s)} \to D \rho(770))$ are similar in magnitude: an interesting relation to be tested by future experimental measurements. |
1809.02616 | Andrzej Buras | Andrzej J. Buras | The Dual QCD @ Work | Talk given at QCD @ Work 2018, Matera, June 2018. 12 pages | null | 10.1051/epjconf/201819200048 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Dual QCD (DQCD) framework, based on the ideas of 't Hooft and Witten, and
developed by Bill Bardeen, Jean-Marc Gerard and myself in the 1980s is not QCD,
a theory of quarks and gluons, but a successful low energy approximation of it
when applied to $K\to\pi\pi$ decays and $K^0-\bar K^0$ mixing. After years of
silence, starting with 2014, this framework has been further developed in order
to improve the SM prediction for the ratio $\epsilon'/\epsilon$, the $\Delta
I=1/2$ rule and $\hat B_K$. Most importantly, this year it has been used for
the calculation of all $K\to\pi\pi$ hadronic matrix elements of BSM operators
which opened the road for the general study of $\epsilon'/\epsilon$ in the
context of the SM effective theory (SMEFT). This talk summarizes briefly the
past successes of this framework and discusses recent developments which lead
to a master formula for $\epsilon'/\epsilon$ valid in any extension of the SM.
This formula should facilitate the search for new physics responsible for the
$\epsilon'/\epsilon$ anomaly hinted by 2015 results from lattice QCD and DQCD.
| [
{
"created": "Fri, 7 Sep 2018 18:00:01 GMT",
"version": "v1"
}
] | 2018-12-05 | [
[
"Buras",
"Andrzej J.",
""
]
] | The Dual QCD (DQCD) framework, based on the ideas of 't Hooft and Witten, and developed by Bill Bardeen, Jean-Marc Gerard and myself in the 1980s is not QCD, a theory of quarks and gluons, but a successful low energy approximation of it when applied to $K\to\pi\pi$ decays and $K^0-\bar K^0$ mixing. After years of silence, starting with 2014, this framework has been further developed in order to improve the SM prediction for the ratio $\epsilon'/\epsilon$, the $\Delta I=1/2$ rule and $\hat B_K$. Most importantly, this year it has been used for the calculation of all $K\to\pi\pi$ hadronic matrix elements of BSM operators which opened the road for the general study of $\epsilon'/\epsilon$ in the context of the SM effective theory (SMEFT). This talk summarizes briefly the past successes of this framework and discusses recent developments which lead to a master formula for $\epsilon'/\epsilon$ valid in any extension of the SM. This formula should facilitate the search for new physics responsible for the $\epsilon'/\epsilon$ anomaly hinted by 2015 results from lattice QCD and DQCD. |
hep-ph/0403033 | Valery Lyubovitskij | Amand Faessler (Tuebingen U.), Th. Gutsche (Tuebingen U.), Sergey
Kovalenko (Santa Maria U., Valparaiso), V. E. Lyubovitskij (Tuebingen U.),
Ivan Schmidt (Santa Maria U., Valparaiso), F. Simkovic (Tuebingen U.) | Vector mesons in nuclear mu-e conversion | 11 pages, 1 figure, to be published in Phys. Lett. B | Phys.Lett.B590:57-62,2004 | 10.1016/j.physletb.2004.03.068 | USM-TH-151 | hep-ph | null | We study nuclear mu-e conversion in the general framework of an effective
Lagrangian approach without referring to any specific realization of the
physics beyond the standard model (SM) responsible for lepton flavor violation
(LFV). We show that vector meson exchange between lepton and nucleon currents
plays an important role in this process. A new issue of this mechanism is the
presence of the strange quark vector current contribution induced by the phi
meson. This allows us to extract new limits on the LFV lepton-quark effective
couplings from the existing experimental data.
| [
{
"created": "Wed, 3 Mar 2004 08:13:04 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Mar 2004 07:58:43 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Faessler",
"Amand",
"",
"Tuebingen U."
],
[
"Gutsche",
"Th.",
"",
"Tuebingen U."
],
[
"Kovalenko",
"Sergey",
"",
"Santa Maria U., Valparaiso"
],
[
"Lyubovitskij",
"V. E.",
"",
"Tuebingen U."
],
[
"Schmidt",
"Ivan",
"",
... | We study nuclear mu-e conversion in the general framework of an effective Lagrangian approach without referring to any specific realization of the physics beyond the standard model (SM) responsible for lepton flavor violation (LFV). We show that vector meson exchange between lepton and nucleon currents plays an important role in this process. A new issue of this mechanism is the presence of the strange quark vector current contribution induced by the phi meson. This allows us to extract new limits on the LFV lepton-quark effective couplings from the existing experimental data. |
hep-ph/9402231 | null | David O. Caldwell and Rabindra N. Mohapatra | Accomodating Solar and Atmospheric Neutrino Deficits, Hot Dark Matter,
and a Double Beta Decay Signal | UCSB-HEP-94-03 and UMD-PP-94-90; { Tex File; 14 pages } (File jnl.tex
included and minor misprints corrected.) | Phys.Rev. D50 (1994) 3477-3483 | 10.1103/PhysRevD.50.3477 | null | hep-ph | null | Neutrino mass explanations of the solar and atmospheric neutrino deficits and
a hot dark matter component require one of three patterns of those masses, as
already pointed out by us. Recently there have been indications of a
non-vanishing amplitude for neutrinoless double beta decay. If this additional
hint of neutrino mass is true, it would make even less likely the one unfavored
pattern (a sterile neutrino giving warm, rather than hot dark matter), would
alter another by making the $\nu_e$ a contributor to the hot dark matter, and
would make the third ($\nu_e$, $\nu_\mu$, and $\nu_\tau$ approximately
degenerate) much more likely than previously. For this third case we construct
a gauge model consistent with other weak interaction data. This model utilizes
a more general version of the see-saw mechanism, which is very likely to be the
source of neutrino mass, if this degenerate pattern is correct. A new supernova
constraint is utilized, and implications and tests of the different mass
matrices are noted.
| [
{
"created": "Fri, 4 Feb 1994 20:51:41 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Feb 1994 16:18:38 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Caldwell",
"David O.",
""
],
[
"Mohapatra",
"Rabindra N.",
""
]
] | Neutrino mass explanations of the solar and atmospheric neutrino deficits and a hot dark matter component require one of three patterns of those masses, as already pointed out by us. Recently there have been indications of a non-vanishing amplitude for neutrinoless double beta decay. If this additional hint of neutrino mass is true, it would make even less likely the one unfavored pattern (a sterile neutrino giving warm, rather than hot dark matter), would alter another by making the $\nu_e$ a contributor to the hot dark matter, and would make the third ($\nu_e$, $\nu_\mu$, and $\nu_\tau$ approximately degenerate) much more likely than previously. For this third case we construct a gauge model consistent with other weak interaction data. This model utilizes a more general version of the see-saw mechanism, which is very likely to be the source of neutrino mass, if this degenerate pattern is correct. A new supernova constraint is utilized, and implications and tests of the different mass matrices are noted. |
1611.01394 | Kalliopi Petraki | Kalliopi Petraki, Marieke Postma and Jordy de Vries | Radiative bound-state-formation cross-sections for dark matter
interacting via a Yukawa potential | v1: 53 pages, many figures; v2: discussion and references added,
results unchanged, published version, 61 pages | null | 10.1007/JHEP04(2017)077 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the cross-sections for the radiative formation of bound states
by dark matter whose interactions are described in the non-relativistic regime
by a Yukawa potential. These cross-sections are important for cosmological and
phenomenological studies of dark matter with long-range interactions, residing
in a hidden sector, as well as for TeV-scale WIMP dark matter. We provide the
leading-order contributions to the cross-sections for the dominant capture
processes occurring via emission of a vector or a scalar boson. We offer a
detailed inspection of their features, including their velocity dependence
within and outside the Coulomb regime, and their resonance structure. For pairs
of annihilating particles, we compare bound-state formation with annihilation.
| [
{
"created": "Fri, 4 Nov 2016 14:25:57 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Apr 2017 17:55:49 GMT",
"version": "v2"
}
] | 2017-04-24 | [
[
"Petraki",
"Kalliopi",
""
],
[
"Postma",
"Marieke",
""
],
[
"de Vries",
"Jordy",
""
]
] | We calculate the cross-sections for the radiative formation of bound states by dark matter whose interactions are described in the non-relativistic regime by a Yukawa potential. These cross-sections are important for cosmological and phenomenological studies of dark matter with long-range interactions, residing in a hidden sector, as well as for TeV-scale WIMP dark matter. We provide the leading-order contributions to the cross-sections for the dominant capture processes occurring via emission of a vector or a scalar boson. We offer a detailed inspection of their features, including their velocity dependence within and outside the Coulomb regime, and their resonance structure. For pairs of annihilating particles, we compare bound-state formation with annihilation. |
0903.1708 | Mohammadmehdi Ettefaghi | M. M. Ettefaghi | Singlet particles as cold dark matter in noncommutative space-time | 14 pages, to appear in Phys. Rev. D | Phys.Rev.D79:065022,2009 | 10.1103/PhysRevD.79.065022 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We extend the noncommutative (NC) standard model to incorporate singlet
particles as cold dark matter. In the NC space-time, the singlet particles can
be coupled to the U(1) gauge field in the adjoint representation. We Study the
relic density of the singlet particles due to the NC induced interaction.
Demanding either the singlet fermion or the singlet scalar to serve as cold
dark matter and the NC induced interactions to be relevant to the dark matter
production, we obtain the corresponding relations between the NC scale and the
dark matter masses, which are consistent with some existing bounds.
| [
{
"created": "Tue, 10 Mar 2009 08:30:16 GMT",
"version": "v1"
}
] | 2010-04-28 | [
[
"Ettefaghi",
"M. M.",
""
]
] | We extend the noncommutative (NC) standard model to incorporate singlet particles as cold dark matter. In the NC space-time, the singlet particles can be coupled to the U(1) gauge field in the adjoint representation. We Study the relic density of the singlet particles due to the NC induced interaction. Demanding either the singlet fermion or the singlet scalar to serve as cold dark matter and the NC induced interactions to be relevant to the dark matter production, we obtain the corresponding relations between the NC scale and the dark matter masses, which are consistent with some existing bounds. |
1502.03385 | Monika Blanke | Monika Blanke | Non-minimally flavour violating dark matter | Proceedings for DISCRETE 2014: Fourth Symposium on Prospects in the
Physics of Discrete Symmetries, 2-6 December 2014, King's College London | null | 10.1088/1742-6596/631/1/012022 | CERN-PH-TH-2015-028, TTP15-004 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Flavour symmetries provide an appealing mechanism to stabilize the dark
matter particle. I present a simple model of quark flavoured dark matter that
goes beyond the framework of minimal flavour violation. I discuss the
phenomenological implications for direct and indirect dark matter detection
experiments, high energy collider searches as well as flavour violating
precision data.
| [
{
"created": "Wed, 11 Feb 2015 17:19:55 GMT",
"version": "v1"
}
] | 2015-08-18 | [
[
"Blanke",
"Monika",
""
]
] | Flavour symmetries provide an appealing mechanism to stabilize the dark matter particle. I present a simple model of quark flavoured dark matter that goes beyond the framework of minimal flavour violation. I discuss the phenomenological implications for direct and indirect dark matter detection experiments, high energy collider searches as well as flavour violating precision data. |
hep-ph/9208216 | null | D. B. DeLaney, S. Jadach, C. Shio, G. Siopsis, and B. F. L. Ward | Multiple photon effects in $pp$ scattering at SSC energies | LaTeX file, uses phyzzx, 7pp + 5 LaTeX figures | Phys.Lett. B292 (1992) 413-416; Erratum-ibid. B302 (1993) 540 | 10.1016/0370-2693(92)91196-G | null | hep-ph | null | The Monte Carlo program SSCYFS2 is used in conjunction with available parton
distribution functions to calculate the effects of multiple photon radiation on
pp scattering at SSC energies. Effects relevant to precision SSC physics such
as Higgs discovery and exploration are illustrated.
| [
{
"created": "Mon, 10 Aug 1992 17:38:20 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"DeLaney",
"D. B.",
""
],
[
"Jadach",
"S.",
""
],
[
"Shio",
"C.",
""
],
[
"Siopsis",
"G.",
""
],
[
"Ward",
"B. F. L.",
""
]
] | The Monte Carlo program SSCYFS2 is used in conjunction with available parton distribution functions to calculate the effects of multiple photon radiation on pp scattering at SSC energies. Effects relevant to precision SSC physics such as Higgs discovery and exploration are illustrated. |
2402.10503 | Ansgar Denner | Ansgar Denner and Stefan Rode | Automated resummation of electroweak Sudakov logarithms in diboson
production at future colliders | 75 pages, 69 pdf figure files, some extra comments added, version
that appeared in Eur. Phys. J. C | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | At energies that are large with respect to the electroweak scale, the
electroweak corrections to scattering processes involve large logarithms that
have to be resummed to obtain decent predictions. Soft-collinear effective
theory (SCET) has been proposed as a suitable framework to allow for this
resummation, while retaining non-logarithmic corrections in a consistent way.
In this paper, we investigate the approximations needed to use this approach
for the calculation of electroweak corrections to off-shell diboson production
at high-energy colliders. Upon implementing the method into a Monte-Carlo
integration code, we provide resummed predictions for cross sections and
distributions at a 3 TeV lepton collider and a 100 TeV proton collider.
| [
{
"created": "Fri, 16 Feb 2024 08:24:09 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Jun 2024 09:42:00 GMT",
"version": "v2"
}
] | 2024-06-04 | [
[
"Denner",
"Ansgar",
""
],
[
"Rode",
"Stefan",
""
]
] | At energies that are large with respect to the electroweak scale, the electroweak corrections to scattering processes involve large logarithms that have to be resummed to obtain decent predictions. Soft-collinear effective theory (SCET) has been proposed as a suitable framework to allow for this resummation, while retaining non-logarithmic corrections in a consistent way. In this paper, we investigate the approximations needed to use this approach for the calculation of electroweak corrections to off-shell diboson production at high-energy colliders. Upon implementing the method into a Monte-Carlo integration code, we provide resummed predictions for cross sections and distributions at a 3 TeV lepton collider and a 100 TeV proton collider. |
1102.2113 | Alberto Tonero | M. Fabbrichesi, R. Percacci, A. Tonero and L. Vecchi | The electroweak S and T parameters from a fixed point condition | 4 pages, 2 figures | Phys.Rev.Lett.107:021803,2011 | 10.1103/PhysRevLett.107.021803 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the standard model without the Higgs boson, where the Goldstone
modes are described by a nonlinear sigma model. We study the renormalization
group flow of the sigma model coupling f and of the electroweak parameters S
and T. The condition that the couplings reach a fixed point at high energy
leaves the low energy values of f and T arbitrary (to be determined
experimentally) and fixes S to a value compatible with electroweak precision
data.
| [
{
"created": "Thu, 10 Feb 2011 13:35:34 GMT",
"version": "v1"
}
] | 2011-07-29 | [
[
"Fabbrichesi",
"M.",
""
],
[
"Percacci",
"R.",
""
],
[
"Tonero",
"A.",
""
],
[
"Vecchi",
"L.",
""
]
] | We consider the standard model without the Higgs boson, where the Goldstone modes are described by a nonlinear sigma model. We study the renormalization group flow of the sigma model coupling f and of the electroweak parameters S and T. The condition that the couplings reach a fixed point at high energy leaves the low energy values of f and T arbitrary (to be determined experimentally) and fixes S to a value compatible with electroweak precision data. |
1211.6818 | Jarah Evslin | Emilio Ciuffoli, Jarah Evslin, Zhimin Wang, Changgen Yang, Xinmin
Zhang and Weili Zhong | Medium Baseline Reactor Neutrino Experiments with 2 Identical Detectors | 17 pages, 7 jpg figures | Phys.Lett. B736 (2014) 110-118 | 10.1016/j.physletb.2014.07.007 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the next 10 years medium baseline reactor neutrino experiments will
attempt to determine the neutrino mass hierarchy and to precisely measure
{\theta}_12. Both of these determinations will be more reliable if data from
identical detectors at distinct baselines are combined. While interference
effects can be eliminated by choosing detector sites orthogonal to the reactor
arrays, one of the greatest challenges facing a determination of the mass
hierarchy is the detector's unknown energy response. By comparing peaks at
similar energies at two identical detectors at distinct baselines, one
eliminates any correlated dependence upon a monotonic energy response. In
addition, a second detector leads to new hierarchy-dependent observables, such
as the ratio of the locations of the maxima of the Fourier cosine transforms.
Simultaneously, one may determine the hierarchy by comparing the {\chi}^2 best
fits of {\Delta}M^2_32 at the two detectors using the spectra associated to
both hierarchies. A second detector at a distinct baseline also breaks the
degeneracy between {\theta}_12 and the background neutrino flux from, for
example, distant reactors and increases the effective target mass, which is
limited by current designs to about 20 kton/detector.
| [
{
"created": "Thu, 29 Nov 2012 06:36:35 GMT",
"version": "v1"
}
] | 2015-11-05 | [
[
"Ciuffoli",
"Emilio",
""
],
[
"Evslin",
"Jarah",
""
],
[
"Wang",
"Zhimin",
""
],
[
"Yang",
"Changgen",
""
],
[
"Zhang",
"Xinmin",
""
],
[
"Zhong",
"Weili",
""
]
] | In the next 10 years medium baseline reactor neutrino experiments will attempt to determine the neutrino mass hierarchy and to precisely measure {\theta}_12. Both of these determinations will be more reliable if data from identical detectors at distinct baselines are combined. While interference effects can be eliminated by choosing detector sites orthogonal to the reactor arrays, one of the greatest challenges facing a determination of the mass hierarchy is the detector's unknown energy response. By comparing peaks at similar energies at two identical detectors at distinct baselines, one eliminates any correlated dependence upon a monotonic energy response. In addition, a second detector leads to new hierarchy-dependent observables, such as the ratio of the locations of the maxima of the Fourier cosine transforms. Simultaneously, one may determine the hierarchy by comparing the {\chi}^2 best fits of {\Delta}M^2_32 at the two detectors using the spectra associated to both hierarchies. A second detector at a distinct baseline also breaks the degeneracy between {\theta}_12 and the background neutrino flux from, for example, distant reactors and increases the effective target mass, which is limited by current designs to about 20 kton/detector. |
1101.1272 | Chang Qin | Qin Chang | Probe a family non-universal Z' boson effects in B(s)-> phi mu(+)
mu(-)decay | 16 pages, 3 figures, 4 table; accepted by Nucl. Phys. B | Nucl.Phys.B845:179-189,2011 | 10.1016/j.nuclphysb.2010.12.003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the recent measurement on ${\cal B}(\bar{B}_s\to \phi
\mu^+\mu^-)$ by CDF collaboration, we study the effects of a family
non-universal $Z^{\prime}$ boson on rare semileptonic $\bar{B}_s \to
\phi\mu^+\mu^-$ decay. In our evaluations, we analyze the dependences of the
dimuon invariant mass spectrum and normalized forward-backward asymmetry on
$Z^{\prime}$ couplings and show that these observables are highly sensitive to
new $Z^{\prime}$ contributions. Three limiting scenarios are presented in the
detailed analyses. Numerically, within the allowed ranges of $Z^{\prime}$
couplings under the constraints from $\bar{B}_s-B_s$ mixing, $B\to\pi K$,
$\bar{B}_d\to(X_s,K,K^{\ast})\mu^+\mu^-$ decays and so on, ${\cal
B}(\bar{B}_s\to \phi \mu^+\mu^-)$ and $A_{FB}^{(L)}(\bar{B}_s\to \phi
\mu^+\mu^-)$ could be enhanced by about 96% and $17%\,(133%)$ respectively at
most by $Z^{\prime}$ contributions. However, ${\cal B}(\bar{B}_s\to \phi
\mu^+\mu^-)$ is hardly to be reduced. Furthermore, the zero crossing in
$A_{FB}(\bar{B}_s\to \phi \mu^+\mu^-)$ spectrum at low dimuon mass always
exists.
| [
{
"created": "Thu, 6 Jan 2011 18:39:17 GMT",
"version": "v1"
}
] | 2015-03-17 | [
[
"Chang",
"Qin",
""
]
] | Motivated by the recent measurement on ${\cal B}(\bar{B}_s\to \phi \mu^+\mu^-)$ by CDF collaboration, we study the effects of a family non-universal $Z^{\prime}$ boson on rare semileptonic $\bar{B}_s \to \phi\mu^+\mu^-$ decay. In our evaluations, we analyze the dependences of the dimuon invariant mass spectrum and normalized forward-backward asymmetry on $Z^{\prime}$ couplings and show that these observables are highly sensitive to new $Z^{\prime}$ contributions. Three limiting scenarios are presented in the detailed analyses. Numerically, within the allowed ranges of $Z^{\prime}$ couplings under the constraints from $\bar{B}_s-B_s$ mixing, $B\to\pi K$, $\bar{B}_d\to(X_s,K,K^{\ast})\mu^+\mu^-$ decays and so on, ${\cal B}(\bar{B}_s\to \phi \mu^+\mu^-)$ and $A_{FB}^{(L)}(\bar{B}_s\to \phi \mu^+\mu^-)$ could be enhanced by about 96% and $17%\,(133%)$ respectively at most by $Z^{\prime}$ contributions. However, ${\cal B}(\bar{B}_s\to \phi \mu^+\mu^-)$ is hardly to be reduced. Furthermore, the zero crossing in $A_{FB}(\bar{B}_s\to \phi \mu^+\mu^-)$ spectrum at low dimuon mass always exists. |
2203.08892 | Amir N. Khan | Amir N. Khan | $\sin^2\theta_W$ and neutrino electromagnetic interactions in
CE$\bar{\nu}_e$NS with different quenching factors | 23 pages, 7 figures and 1 table; More quenching factor models were
added; Analysis extended | null | null | null | hep-ph hep-ex | http://creativecommons.org/publicdomain/zero/1.0/ | Recently, evidence for the observation of about 2 keV and below nuclear
recoils from the coherent scattering of reactor anti-neutrinos off the
germanium nuclei has been reported. We analyze the observed data to estimate
the value of the weak mixing angle and constrain the neutrino millicharge,
magnetic moment, charge radius and anapole moment contributing to the coherent
scattering process. Currently, there is no definite model available for the
quenching factor at such low energies. To this end, we consider various models
of the quenching factor and show how it affects the interpretation of the
obtained results. We find that the bounds obtained are stronger in some cases
while comparable or weaker in other cases which show a strong dependence on the
choice and accuracy of a particular quenching factor model. The results are the
first at such low-energy nuclear recoils. We present an exhaustive list of
analytical functions for the different quenching factors corresponding to the
existing models and to the data from various experiments. Such functions will
be useful for any new physics study using the nuclear recoils due to the
reactor neutrinos.
| [
{
"created": "Wed, 16 Mar 2022 19:07:15 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Jun 2022 20:54:48 GMT",
"version": "v2"
}
] | 2022-06-16 | [
[
"Khan",
"Amir N.",
""
]
] | Recently, evidence for the observation of about 2 keV and below nuclear recoils from the coherent scattering of reactor anti-neutrinos off the germanium nuclei has been reported. We analyze the observed data to estimate the value of the weak mixing angle and constrain the neutrino millicharge, magnetic moment, charge radius and anapole moment contributing to the coherent scattering process. Currently, there is no definite model available for the quenching factor at such low energies. To this end, we consider various models of the quenching factor and show how it affects the interpretation of the obtained results. We find that the bounds obtained are stronger in some cases while comparable or weaker in other cases which show a strong dependence on the choice and accuracy of a particular quenching factor model. The results are the first at such low-energy nuclear recoils. We present an exhaustive list of analytical functions for the different quenching factors corresponding to the existing models and to the data from various experiments. Such functions will be useful for any new physics study using the nuclear recoils due to the reactor neutrinos. |
0905.3028 | Sho Ozaki | S. Ozaki, H. Nagahiro, A. Hosaka, O. Scholten | A coupled-channel analysis for phi-photoproduction with Lambda(1520) | 28 pages, 21 figures | Phys.Rev.C80:035201,2009; Erratum-ibid.C81:059901,2010 | 10.1103/PhysRevC.80.035201 10.1103/PhysRevC.81.059901 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate photoproduction of $\phi$-mesons off protons within a
coupled-channel effective-Lagrangian method which is based on the K-matrix
approach. Since the threshold energy of the $K\Lambda(1520)$ channel is close
to that of $\phi N$, the contribution of this channel to $\phi$-photoproduction
near the threshold energy region may give rise to some unexpected structures.
In the transition amplitude $K\Lambda(1520) \to \phi N$, the kinematics allows
an intermediate kaon to be on-shell. This happens in the energy region where a
peak structure has been observed in $\phi$-photoproduction. In our calculations
the on-shell kaon effect indeed reproduces a peak structure, however, with a
magnitude that is far too small to explain the observed effect. As a following
step we introduce a nucleon resonance in our model. The coupling of the
resonance to the $K\Lambda(1520)$ and $\phi N$ channels is not suppressed by
the OZI rule if the resonance contains a dominant hidden strangeness component.
We find that the resonance can reproduce a peak structure of the correct
magnitude at the right energy. We also investigate the effects of coupled
channels and the resonance on the angular distribution and the spin density
matrices for $\phi$ photoproduction.
| [
{
"created": "Tue, 19 May 2009 06:33:15 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Ozaki",
"S.",
""
],
[
"Nagahiro",
"H.",
""
],
[
"Hosaka",
"A.",
""
],
[
"Scholten",
"O.",
""
]
] | We investigate photoproduction of $\phi$-mesons off protons within a coupled-channel effective-Lagrangian method which is based on the K-matrix approach. Since the threshold energy of the $K\Lambda(1520)$ channel is close to that of $\phi N$, the contribution of this channel to $\phi$-photoproduction near the threshold energy region may give rise to some unexpected structures. In the transition amplitude $K\Lambda(1520) \to \phi N$, the kinematics allows an intermediate kaon to be on-shell. This happens in the energy region where a peak structure has been observed in $\phi$-photoproduction. In our calculations the on-shell kaon effect indeed reproduces a peak structure, however, with a magnitude that is far too small to explain the observed effect. As a following step we introduce a nucleon resonance in our model. The coupling of the resonance to the $K\Lambda(1520)$ and $\phi N$ channels is not suppressed by the OZI rule if the resonance contains a dominant hidden strangeness component. We find that the resonance can reproduce a peak structure of the correct magnitude at the right energy. We also investigate the effects of coupled channels and the resonance on the angular distribution and the spin density matrices for $\phi$ photoproduction. |
hep-ph/0110198 | Pelaez | J. R. Pelaez and A. Gomez Nicola | Complete meson-meson scattering within one loop in Chiral Perturbation
Theory: Unitarization and resonances | 4 pages, To appear in the Proceedings of the IX International
Conference on Hadron Spectroscopy, HADRON2001, IHEP, Protvino, Russia, August
2001 | AIP Conf.Proc. 619 (2002) 739-742 | 10.1063/1.1482530 | null | hep-ph | null | We review our recent one-loop calculation of all the two meson scattering
amplitudes within SU(3) Chiral Perturbation Theory, i.e. with pions, kaons and
etas. By unitarizing these amplitudes we are able to generate dynamically the
lightest resonances in meson-meson scattering. We thus obtain a remarkable
description of the meson-meson scattering data right from threshold up to 1.2
GeV, in terms of chiral parameters in good agreement with previous
determinations.
| [
{
"created": "Mon, 15 Oct 2001 18:40:56 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Pelaez",
"J. R.",
""
],
[
"Nicola",
"A. Gomez",
""
]
] | We review our recent one-loop calculation of all the two meson scattering amplitudes within SU(3) Chiral Perturbation Theory, i.e. with pions, kaons and etas. By unitarizing these amplitudes we are able to generate dynamically the lightest resonances in meson-meson scattering. We thus obtain a remarkable description of the meson-meson scattering data right from threshold up to 1.2 GeV, in terms of chiral parameters in good agreement with previous determinations. |
1101.0325 | C. Pallis | C. Pallis and N. Toumbas | Non-Minimal Sneutrino Inflation, Peccei-Quinn Phase Transition and
non-Thermal Leptogenesis | 21 pages including 3 figures; Final version | JCAP 1102:019,2011 | 10.1088/1475-7516/2011/02/019 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a phenomenological extension of the minimal supersymmetric
standard model which incorporates non-minimal chaotic inflation, driven by a
quartic potential associated with the lightest right-handed sneutrino.
Inflation is followed by a Peccei-Quinn phase transition based on
renormalizable superpotential terms, which resolves the strong CP and mu
problems of the minimal supersymmetric standard model provided that one related
parameter of the superpotential is somewhat small. Baryogenesis occurs via
non-thermal leptogenesis, which is realized by the inflaton decay. Confronting
our scenario with the current observational data on the inflationary
observables, the baryon assymetry of the universe, the gravitino limit on the
reheating temperature and the upper bound on the light neutrino masses, we
constrain the effective Yukawa coupling involved in the decay of the inflaton
to relatively small values and the inflaton mass to values lower than 10^12
GeV.
| [
{
"created": "Sat, 1 Jan 2011 06:11:57 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Feb 2011 15:50:58 GMT",
"version": "v2"
},
{
"created": "Sun, 14 Aug 2011 03:33:58 GMT",
"version": "v3"
}
] | 2015-03-17 | [
[
"Pallis",
"C.",
""
],
[
"Toumbas",
"N.",
""
]
] | We consider a phenomenological extension of the minimal supersymmetric standard model which incorporates non-minimal chaotic inflation, driven by a quartic potential associated with the lightest right-handed sneutrino. Inflation is followed by a Peccei-Quinn phase transition based on renormalizable superpotential terms, which resolves the strong CP and mu problems of the minimal supersymmetric standard model provided that one related parameter of the superpotential is somewhat small. Baryogenesis occurs via non-thermal leptogenesis, which is realized by the inflaton decay. Confronting our scenario with the current observational data on the inflationary observables, the baryon assymetry of the universe, the gravitino limit on the reheating temperature and the upper bound on the light neutrino masses, we constrain the effective Yukawa coupling involved in the decay of the inflaton to relatively small values and the inflaton mass to values lower than 10^12 GeV. |
0808.1906 | Thomas G. Rizzo | Thomas G Rizzo | Z' Physics at the LHC and the LHeC | 4 pages, 4 figs; talk given at ICHEP08, Philadelphia PA, 30 July-5
Aug. 2008 | null | null | slac-PUB-13370 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The methods which can be employed to determine the properties of new neutral
resonant states that may be observed in the Drell-Yan channel at the LHC are
reviewed. If these states are sufficiently light we discuss how polarized $ep$
scattering at the LHeC can assist in the determination of their couplings to
the Standard Model (SM) fermions.
| [
{
"created": "Wed, 13 Aug 2008 21:52:52 GMT",
"version": "v1"
}
] | 2008-08-15 | [
[
"Rizzo",
"Thomas G",
""
]
] | The methods which can be employed to determine the properties of new neutral resonant states that may be observed in the Drell-Yan channel at the LHC are reviewed. If these states are sufficiently light we discuss how polarized $ep$ scattering at the LHeC can assist in the determination of their couplings to the Standard Model (SM) fermions. |
1412.6025 | Jens Braun | Jens Braun, Walid Ahmed Mian, Stefan Rechenberger | Delayed Magnetic Catalysis | 5 pages, 3 figures | null | null | null | hep-ph cond-mat.str-el hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the effect of an external magnetic field on the chiral phase
transition in the theory of the strong interaction by means of a
renormalization-group (RG) fixed-point analysis, relying on only one physical
input parameter, the strong coupling at a given large momentum scale. To be
specific, we consider the interplay of the RG flow of four-quark interactions
and the running gauge coupling. Depending on the temperature and the strength
of the magnetic field, the gauge coupling can drive the quark sector to
criticality, resulting in chiral symmetry breaking. In accordance with lattice
Monte-Carlo simulations, we find that the chiral phase transition temperature
decreases for small values of the external magnetic field. For large magnetic
field strengths, however, our fixed-point study predicts that the phase
transition temperature increases monotonically.
| [
{
"created": "Thu, 18 Dec 2014 19:43:52 GMT",
"version": "v1"
}
] | 2014-12-19 | [
[
"Braun",
"Jens",
""
],
[
"Mian",
"Walid Ahmed",
""
],
[
"Rechenberger",
"Stefan",
""
]
] | We study the effect of an external magnetic field on the chiral phase transition in the theory of the strong interaction by means of a renormalization-group (RG) fixed-point analysis, relying on only one physical input parameter, the strong coupling at a given large momentum scale. To be specific, we consider the interplay of the RG flow of four-quark interactions and the running gauge coupling. Depending on the temperature and the strength of the magnetic field, the gauge coupling can drive the quark sector to criticality, resulting in chiral symmetry breaking. In accordance with lattice Monte-Carlo simulations, we find that the chiral phase transition temperature decreases for small values of the external magnetic field. For large magnetic field strengths, however, our fixed-point study predicts that the phase transition temperature increases monotonically. |
2003.01657 | Tom Steele | F.A. Chishtie, Zhuo-Ran Huang, M. Reimer, T.G. Steele, Zhi-Wei Wang | Transformation of scalar couplings between Coleman-Weinberg and MS
schemes | 12 pages, 5 figures. V2 has additional figures, extended discussion,
and additional references | Phys. Rev. D 102, 076021 (2020) | 10.1103/PhysRevD.102.076021 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Coleman-Weinberg (CW) renormalization scheme for renormalization-group
improvement of the effective potential is particularly valuable for CW
symmetry-breaking mechanisms (including the challenging case of models with
multiple scalar fields). CW mechanism is typically studied using models with
classical scale invariance which not only provide a possibility for an
alternative symmetry breaking mechanism but also partially address the gauge
hierarchies through dimensional transmutation. As outlined in our discussion
section, when the couplings are not large, models with CW symmetry-breaking
mechanisms have also been shown to naturally provide the strong first-order
phase transition necessary for stochastic gravitational wave signals. A full
understanding of the CW-MS scheme transformation of couplings thus becomes
important in the era of gravitational wave detection and precision coupling
measurements. A generalized Coleman-Weinberg (GCW) renormalization scheme is
formulated and methods for transforming scalar self-couplings between the GCW
and MS (minimal-subtraction) renormalization schemes are developed. Scalar
$\lambda\Phi^4$ theory with global $O(4)$ symmetry is explicitly studied up to
six-loop order to explore the magnitude of this scheme transformation effect on
the couplings. The dynamical rescaling of renormalization scales between the
GCW and MS schemes can lead to significant (order of 10\%) differences in the
coupling at any order, and consequently GCW-MS scheme transformation effects
must be considered within precision determinations of scalar couplings in
extensions of the Standard Model.
| [
{
"created": "Tue, 3 Mar 2020 17:34:23 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Oct 2020 16:37:32 GMT",
"version": "v2"
}
] | 2020-11-04 | [
[
"Chishtie",
"F. A.",
""
],
[
"Huang",
"Zhuo-Ran",
""
],
[
"Reimer",
"M.",
""
],
[
"Steele",
"T. G.",
""
],
[
"Wang",
"Zhi-Wei",
""
]
] | The Coleman-Weinberg (CW) renormalization scheme for renormalization-group improvement of the effective potential is particularly valuable for CW symmetry-breaking mechanisms (including the challenging case of models with multiple scalar fields). CW mechanism is typically studied using models with classical scale invariance which not only provide a possibility for an alternative symmetry breaking mechanism but also partially address the gauge hierarchies through dimensional transmutation. As outlined in our discussion section, when the couplings are not large, models with CW symmetry-breaking mechanisms have also been shown to naturally provide the strong first-order phase transition necessary for stochastic gravitational wave signals. A full understanding of the CW-MS scheme transformation of couplings thus becomes important in the era of gravitational wave detection and precision coupling measurements. A generalized Coleman-Weinberg (GCW) renormalization scheme is formulated and methods for transforming scalar self-couplings between the GCW and MS (minimal-subtraction) renormalization schemes are developed. Scalar $\lambda\Phi^4$ theory with global $O(4)$ symmetry is explicitly studied up to six-loop order to explore the magnitude of this scheme transformation effect on the couplings. The dynamical rescaling of renormalization scales between the GCW and MS schemes can lead to significant (order of 10\%) differences in the coupling at any order, and consequently GCW-MS scheme transformation effects must be considered within precision determinations of scalar couplings in extensions of the Standard Model. |
1906.08641 | Valery Lyubovitskij | Thomas Gutsche, Valery E. Lyubovitskij, Ivan Schmidt | Electromagnetic properties of the nucleon and the Roper resonance in
soft-wall AdS/QCD at finite temperature | 14 pages. arXiv admin note: text overlap with arXiv:1712.08410 | Nucl. Phys. B952 (2020) 114934 | 10.1016/j.nuclphysb.2020.114934 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a study of the nucleon electromagnetic form factors and of the
Roper-nucleon transition at finite small temperature $T$, using an extended
version of a soft-wall AdS/QCD approach developed by us previously. In the
action we introduce the effective potential, which has quadratic dependence on
the holographic coordinate $z$ and depends on both the gluon and quark
condensates. Choosing the AdS geometry we restrict ourselves to the AdS
Poincar\'e metric, because the contribution of the AdS-Schwarzschild geometry
starts at next-to-leading order ${\cal O}(T^4)$. Hence, one can neglect the
temperature dependence of the AdS geometry at small $T$. This is consistent
with the Hawking-Page phase transition at a critical temperature representing
the transition between thermal AdS/QCD and AdS-Schwarzschild geometry. In the
small temperature regime we base our analysis on the temperature dependence of
the effective potential, which starts at order ${\cal O}(T^2)$, due to the
leading contribution from the quark condensate. As applications we present the
analysis of properties of the nucleon and Roper resonance (masses, form
factors, and helicity amplitudes) at low temperatures.
| [
{
"created": "Wed, 19 Jun 2019 09:03:28 GMT",
"version": "v1"
},
{
"created": "Fri, 31 Jan 2020 15:14:07 GMT",
"version": "v2"
}
] | 2020-02-04 | [
[
"Gutsche",
"Thomas",
""
],
[
"Lyubovitskij",
"Valery E.",
""
],
[
"Schmidt",
"Ivan",
""
]
] | We present a study of the nucleon electromagnetic form factors and of the Roper-nucleon transition at finite small temperature $T$, using an extended version of a soft-wall AdS/QCD approach developed by us previously. In the action we introduce the effective potential, which has quadratic dependence on the holographic coordinate $z$ and depends on both the gluon and quark condensates. Choosing the AdS geometry we restrict ourselves to the AdS Poincar\'e metric, because the contribution of the AdS-Schwarzschild geometry starts at next-to-leading order ${\cal O}(T^4)$. Hence, one can neglect the temperature dependence of the AdS geometry at small $T$. This is consistent with the Hawking-Page phase transition at a critical temperature representing the transition between thermal AdS/QCD and AdS-Schwarzschild geometry. In the small temperature regime we base our analysis on the temperature dependence of the effective potential, which starts at order ${\cal O}(T^2)$, due to the leading contribution from the quark condensate. As applications we present the analysis of properties of the nucleon and Roper resonance (masses, form factors, and helicity amplitudes) at low temperatures. |
2112.02232 | Rishabh Jain | Howard Baer, Vernon Barger, Rishabh Jain, Chung Kao and Dibyashree
Sengupta, Xerxes Tata | Detecting Heavy Higgs Bosons from Natural SUSY at a 100 TeV Hadron
Collider | 20 pages, 11 figures Substantial revision in version.2 includes heavy
Higgs boson production from bottom quark fusion processes. Results and
conclusions are considerably changed from version.1 | null | 10.1103/PhysRevD.105.095039 | OU-HEP-211202 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Supersymmetric models with radiatively-driven naturalness (RNS) enjoy low
electroweak fine-tuning whilst respecting LHC search limits on gluinos and top
squarks and allowing for $m_h\simeq 125$ GeV. While the heavier Higgs bosons
$H,\ A$ may have TeV-scale masses, the SUSY conserving $\mu$ parameter must lie
in the few hundred GeV range. Thus, in natural SUSY models there should occur
large heavy Higgs boson branching fractions to electroweakinos, with Higgs
boson decays to higgsino plus gaugino dominating when they are kinematically
accessible. These SUSY decays can open up new avenues for discovery. We
investigate the prospects of discovering heavy neutral Higgs bosons $H$ and $A$
decaying into light plus heavy chargino pairs which can yield a four isolated
lepton plus missing transverse energy signature at the LHC and at a future 100
TeV $pp$ collider. We find that discovery of heavy Higgs decay to
electroweakinos via its $4\ell$ decay mode is very difficult at HL-LHC. For
FCC-hh or SPPC, we study the $H,\ A \to $ SUSY reaction along with dominant
physics backgrounds from the Standard Model and devise suitable selection
requirements to extract a clean signal for FCC-hh or SPPC with $\sqrt{s}=100$
TeV, assuming an integrated luminosity of 15 $ab^{-1}$. We find that while a
conventional cut-and-count analysis yields a signal statistical significance
greater than $5\sigma$ for $m_{A,H}\sim 1.1-1.65$ TeV, a boosted-decision-tree
analysis allows for heavy Higgs signal discovery at FCC-hh or SPPC for
$m_{A,H}\sim 1-2$ TeV.
| [
{
"created": "Sat, 4 Dec 2021 03:50:45 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Apr 2022 08:38:36 GMT",
"version": "v2"
},
{
"created": "Wed, 4 May 2022 13:27:11 GMT",
"version": "v3"
}
] | 2022-06-08 | [
[
"Baer",
"Howard",
""
],
[
"Barger",
"Vernon",
""
],
[
"Jain",
"Rishabh",
""
],
[
"Kao",
"Chung",
""
],
[
"Sengupta",
"Dibyashree",
""
],
[
"Tata",
"Xerxes",
""
]
] | Supersymmetric models with radiatively-driven naturalness (RNS) enjoy low electroweak fine-tuning whilst respecting LHC search limits on gluinos and top squarks and allowing for $m_h\simeq 125$ GeV. While the heavier Higgs bosons $H,\ A$ may have TeV-scale masses, the SUSY conserving $\mu$ parameter must lie in the few hundred GeV range. Thus, in natural SUSY models there should occur large heavy Higgs boson branching fractions to electroweakinos, with Higgs boson decays to higgsino plus gaugino dominating when they are kinematically accessible. These SUSY decays can open up new avenues for discovery. We investigate the prospects of discovering heavy neutral Higgs bosons $H$ and $A$ decaying into light plus heavy chargino pairs which can yield a four isolated lepton plus missing transverse energy signature at the LHC and at a future 100 TeV $pp$ collider. We find that discovery of heavy Higgs decay to electroweakinos via its $4\ell$ decay mode is very difficult at HL-LHC. For FCC-hh or SPPC, we study the $H,\ A \to $ SUSY reaction along with dominant physics backgrounds from the Standard Model and devise suitable selection requirements to extract a clean signal for FCC-hh or SPPC with $\sqrt{s}=100$ TeV, assuming an integrated luminosity of 15 $ab^{-1}$. We find that while a conventional cut-and-count analysis yields a signal statistical significance greater than $5\sigma$ for $m_{A,H}\sim 1.1-1.65$ TeV, a boosted-decision-tree analysis allows for heavy Higgs signal discovery at FCC-hh or SPPC for $m_{A,H}\sim 1-2$ TeV. |
hep-ph/9609435 | Xiang Qian Luo | Lian Hu, Xiang-Qian Luo, Qi-Zhou Chen, Xi-Yan Fang, Shuo-Hong Guo | Glueball Masses from Hamiltonian Lattice QCD | 12 pages, Latex, figures to be sent upon request | Commun.Theor.Phys. 28 (1997) 327-332 | 10.1088/0253-6102/28/3/327 | null | hep-ph hep-lat | null | We calculate the masses of the $0^{++}$, $0^{--}$ and $1^{+-}$ glueballs from
QCD in 3+1 dimensions using an eigenvalue equation method for Hamiltonian
lattice QCD developed and described elsewhere by the authors. The mass ratios
become approximately constants in the coupling region $6/g^2 \in [6.0,6.4]$,
from which we estimate $M(0^{--})/M(0^{++})=2.44 \pm 0.05 \pm 0.20$ and
$M(1^{+-})/M(0^{++})=1.91 \pm 0.05 \pm 0.12$.
| [
{
"created": "Mon, 23 Sep 1996 08:16:31 GMT",
"version": "v1"
}
] | 2018-01-17 | [
[
"Hu",
"Lian",
""
],
[
"Luo",
"Xiang-Qian",
""
],
[
"Chen",
"Qi-Zhou",
""
],
[
"Fang",
"Xi-Yan",
""
],
[
"Guo",
"Shuo-Hong",
""
]
] | We calculate the masses of the $0^{++}$, $0^{--}$ and $1^{+-}$ glueballs from QCD in 3+1 dimensions using an eigenvalue equation method for Hamiltonian lattice QCD developed and described elsewhere by the authors. The mass ratios become approximately constants in the coupling region $6/g^2 \in [6.0,6.4]$, from which we estimate $M(0^{--})/M(0^{++})=2.44 \pm 0.05 \pm 0.20$ and $M(1^{+-})/M(0^{++})=1.91 \pm 0.05 \pm 0.12$. |
hep-ph/9807526 | Xerxes Tata | Xerxes Tata (University of Hawaii) | Developments in Supersymmetry Phenomenology | 9 pages, 3 figures, uses psfig.sty, sprocl.sty, Talk presented at
PASCOS-98, March 1998 | null | null | UH-511-911-98 | hep-ph | null | We survey strategies generally employed for SUSY discovery at colliders and
then discuss how these may have to be altered for SUSY searches at the Tevatron
if $\tan\beta$ is large. We also discuss the reach of the Tevatron and the LHC
in gauge-mediated SUSY breaking scenarios, assuming that the NLSP decays into
photons. Finally, we briefly recapitulate measurements (which serve to guide us
to the underlying theory) that might be possible at future colliders if
supersymmetry is discovered.
| [
{
"created": "Wed, 29 Jul 1998 00:48:10 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Tata",
"Xerxes",
"",
"University of Hawaii"
]
] | We survey strategies generally employed for SUSY discovery at colliders and then discuss how these may have to be altered for SUSY searches at the Tevatron if $\tan\beta$ is large. We also discuss the reach of the Tevatron and the LHC in gauge-mediated SUSY breaking scenarios, assuming that the NLSP decays into photons. Finally, we briefly recapitulate measurements (which serve to guide us to the underlying theory) that might be possible at future colliders if supersymmetry is discovered. |
hep-ph/0402120 | Michael Trott | Michael Trott | Improving Extractions of |Vcb| and mb from the Hadronic Invariant Mass
Moments of Semileptonic Inclusive B decay | 28 pages, 2 figures, Final Version, to appear in Phys. Rev. D. Some
discussion modified, functional form of Eqn (8) simplified and typos fixed | Phys.Rev.D70:073003,2004 | 10.1103/PhysRevD.70.073003 | null | hep-ph | null | We calculate the hadronic tensor for inclusive semileptonic B decay to
O(alpha_s). This allows O(alpha_s Lambda_{QCD}/mb) corrections to hadronic
invariant mass observables to be directly evaluated with experimentally
required cuts on phase space. Several moments of phenomenological interest are
presented to O(alpha_s Lambda_{QCD}/mb) and O(Lambda_{QCD}^3/mb^3), allowing a
consistent extraction of the HQET parameters up to O(Lambda_{QCD}^3/mb^3) and
the b quark mass with theoretical error ~ 50 MeV. The hadronic invariant mass
spectrum is examined with a general moment to obtain observables that test the
theoretical error estimate assigned to these parameters; in particular,
fractional moments that directly test the OPE for inconsistencies in the
hadronic invariant mass spectrum are reported. The mb Lambda_{QCD}/mc^2
expansion present for fractional moments of the hadronic invariant mass spectum
is discussed and shown to introduce a numerically suppressed uncertainty of
O(mb^4 Lambda_{QCD}^4/mc^8).
| [
{
"created": "Wed, 11 Feb 2004 20:06:46 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Mar 2004 22:40:36 GMT",
"version": "v2"
},
{
"created": "Wed, 15 Sep 2004 14:18:25 GMT",
"version": "v3"
}
] | 2014-11-17 | [
[
"Trott",
"Michael",
""
]
] | We calculate the hadronic tensor for inclusive semileptonic B decay to O(alpha_s). This allows O(alpha_s Lambda_{QCD}/mb) corrections to hadronic invariant mass observables to be directly evaluated with experimentally required cuts on phase space. Several moments of phenomenological interest are presented to O(alpha_s Lambda_{QCD}/mb) and O(Lambda_{QCD}^3/mb^3), allowing a consistent extraction of the HQET parameters up to O(Lambda_{QCD}^3/mb^3) and the b quark mass with theoretical error ~ 50 MeV. The hadronic invariant mass spectrum is examined with a general moment to obtain observables that test the theoretical error estimate assigned to these parameters; in particular, fractional moments that directly test the OPE for inconsistencies in the hadronic invariant mass spectrum are reported. The mb Lambda_{QCD}/mc^2 expansion present for fractional moments of the hadronic invariant mass spectum is discussed and shown to introduce a numerically suppressed uncertainty of O(mb^4 Lambda_{QCD}^4/mc^8). |
1205.5727 | Sven-Olaf Moch | H. Kawamura, N. A. Lo Presti, S. Moch, A. Vogt | On the next-to-next-to-leading order QCD corrections to heavy-quark
production in deep-inelastic scattering | 62 pages, LaTeX, 13 figures. Erratum for eq.(B.7) | null | 10.1016/j.nuclphysb.2012.07.001 | KEK-TH 1378; LTH 944; DESY 12-050; LPN 12-048; SFB/CPP-12-21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The contribution of quarks with masses m >> Lambda_QCD is the only part of
the structure functions in deep-inelastic scattering (DIS) which is not yet
known at the next-to-next-to-leading order (NNLO) of perturbative QCD. We
present improved partial NNLO results for the most important structure function
F_2(x,Q^2) near the partonic threshold, in the high-energy (small-x) limit and
at high scales Q^2 >> m^2; and employ these results to construct approximations
for the gluon and quark coefficient functions which cover the full kinematic
plane. The approximation uncertainties are carefully investigated, and found to
be large only at very small values, x smaller about 10^-3, of the Bjorken
variable.
| [
{
"created": "Fri, 25 May 2012 15:24:11 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Aug 2016 15:05:53 GMT",
"version": "v2"
}
] | 2016-08-09 | [
[
"Kawamura",
"H.",
""
],
[
"Presti",
"N. A. Lo",
""
],
[
"Moch",
"S.",
""
],
[
"Vogt",
"A.",
""
]
] | The contribution of quarks with masses m >> Lambda_QCD is the only part of the structure functions in deep-inelastic scattering (DIS) which is not yet known at the next-to-next-to-leading order (NNLO) of perturbative QCD. We present improved partial NNLO results for the most important structure function F_2(x,Q^2) near the partonic threshold, in the high-energy (small-x) limit and at high scales Q^2 >> m^2; and employ these results to construct approximations for the gluon and quark coefficient functions which cover the full kinematic plane. The approximation uncertainties are carefully investigated, and found to be large only at very small values, x smaller about 10^-3, of the Bjorken variable. |
2308.05743 | Berndt Muller | John W. Harris and Berndt M\"uller | "QGP Signatures" Revisited | 42 pages, 47 figures | null | null | null | hep-ph nucl-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | We revisit the graphic table of QCD signatures in our 1996 Annual Reviews
article "The Search for the Quark-Gluon Plasma" and assess the progress that
has been made since its publication towards providing quantitative evidence for
the formation of a quark-gluon plasma in relativistic heavy-ion collisions and
its characteristic properties.
| [
{
"created": "Thu, 10 Aug 2023 17:59:31 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Aug 2023 16:04:38 GMT",
"version": "v2"
},
{
"created": "Tue, 6 Feb 2024 20:21:47 GMT",
"version": "v3"
}
] | 2024-02-08 | [
[
"Harris",
"John W.",
""
],
[
"Müller",
"Berndt",
""
]
] | We revisit the graphic table of QCD signatures in our 1996 Annual Reviews article "The Search for the Quark-Gluon Plasma" and assess the progress that has been made since its publication towards providing quantitative evidence for the formation of a quark-gluon plasma in relativistic heavy-ion collisions and its characteristic properties. |
hep-ph/0205283 | F. . Krauss | F. Krauss | Matrix Elements and Parton Showers in Hadronic Interactions | 14 pages, 8 figures | JHEP 0208:015,2002 | 10.1088/1126-6708/2002/08/015 | null | hep-ph | null | A method is suggested to combine tree level QCD matrix for the production of
multi jet final states and the parton shower in hadronic interactions. The
method follows closely an algorithm developed recently for the case of $e^+e^-$
annihilations.
| [
{
"created": "Fri, 24 May 2002 16:45:05 GMT",
"version": "v1"
}
] | 2011-05-05 | [
[
"Krauss",
"F.",
""
]
] | A method is suggested to combine tree level QCD matrix for the production of multi jet final states and the parton shower in hadronic interactions. The method follows closely an algorithm developed recently for the case of $e^+e^-$ annihilations. |
1504.04371 | Matti Heikinheimo | Matti Heikinheimo, Martti Raidal, Christian Spethmann and Hardi
Veerm\"ae | Evidence for Dark Matter Self-Interactions via Collisionless Shocks in
Cluster Mergers | Matches the version to be published in Physics Letters B | null | 10.1016/j.physletb.2015.08.012 | null | hep-ph astro-ph.HE physics.plasm-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | While dark matter self-interactions may solve several problems with structure
formation, so far only the effects of two-body scatterings of dark matter
particles have been considered. We show that, if a subdominant component of
dark matter is charged under an unbroken $U(1)$ gauge group, collective dark
plasma effects need to be taken into account to understand its dynamics. Plasma
instabilities can lead to collisionless dark matter shocks in galaxy cluster
mergers which might have been already observed in the Abell 3827 and 520
clusters. As a concrete model we propose a thermally produced dark pair plasma
of vectorlike fermions. In this scenario the interacting dark matter component
is expected to be separated from the stars and the non-interacting dark matter
halos in cluster collisions. In addition, the missing satellite problem is
softened, while constraints from all other astrophysical and cosmological
observations are avoided.
| [
{
"created": "Thu, 16 Apr 2015 20:00:26 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Jun 2015 13:49:47 GMT",
"version": "v2"
},
{
"created": "Thu, 6 Aug 2015 08:15:59 GMT",
"version": "v3"
}
] | 2015-09-30 | [
[
"Heikinheimo",
"Matti",
""
],
[
"Raidal",
"Martti",
""
],
[
"Spethmann",
"Christian",
""
],
[
"Veermäe",
"Hardi",
""
]
] | While dark matter self-interactions may solve several problems with structure formation, so far only the effects of two-body scatterings of dark matter particles have been considered. We show that, if a subdominant component of dark matter is charged under an unbroken $U(1)$ gauge group, collective dark plasma effects need to be taken into account to understand its dynamics. Plasma instabilities can lead to collisionless dark matter shocks in galaxy cluster mergers which might have been already observed in the Abell 3827 and 520 clusters. As a concrete model we propose a thermally produced dark pair plasma of vectorlike fermions. In this scenario the interacting dark matter component is expected to be separated from the stars and the non-interacting dark matter halos in cluster collisions. In addition, the missing satellite problem is softened, while constraints from all other astrophysical and cosmological observations are avoided. |
hep-ph/9603275 | Kuang-Ta Chao | Cong-Feng Qiao, Chong Sheng Li, Kuang-Ta Chao (Peking University) | Top Quark Decays into Heavy Quark Mesons | 15 pages in LaTex form, 4 figures included | Phys.Rev.D54:5606-5610,1996 | 10.1103/PhysRevD.54.5606 | PUTP-96-03 | hep-ph | null | For top quark decays into heavy quark mesons $\Upsilon$ and $\bar{B}_c^*$ , a
complete calculation to the leading order both in QCD coupling constant
$\alpha_s$ and in $v$, the typical velocity of the heavy quarks inside the
mesons, is performed. Relatons between the top quark mass and the decay
branching ratios are studied. Comparion with the results which are obtained by
using the quark frangmentation functions is also discussed. The branching
ratios are consistent (within a factor of $2\sim 3 $) with that obtained using
fragmentation functions at $m_t\sim 150$ GeV.
| [
{
"created": "Tue, 12 Mar 1996 04:28:03 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Qiao",
"Cong-Feng",
"",
"Peking University"
],
[
"Li",
"Chong Sheng",
"",
"Peking University"
],
[
"Chao",
"Kuang-Ta",
"",
"Peking University"
]
] | For top quark decays into heavy quark mesons $\Upsilon$ and $\bar{B}_c^*$ , a complete calculation to the leading order both in QCD coupling constant $\alpha_s$ and in $v$, the typical velocity of the heavy quarks inside the mesons, is performed. Relatons between the top quark mass and the decay branching ratios are studied. Comparion with the results which are obtained by using the quark frangmentation functions is also discussed. The branching ratios are consistent (within a factor of $2\sim 3 $) with that obtained using fragmentation functions at $m_t\sim 150$ GeV. |
2404.08733 | Stephen Parke | Stephen J. Parke and Renata Zukanovich Funchal | A Mass Ordering Sum Rule for the Neutrino Disappearance Channels in T2K,
NOvA and JUNO | 7 pages, 2 figures | null | null | FERMILAB-PUB-24-0117-T | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We revisit a method for determining the neutrino mass ordering by using
precision measurements of the atmospheric $\Delta m^2$'s in both electron
neutrino and muon neutrino disappearance channels, proposed by the authors in
2005 (hep-ph/0503283). The mass ordering is a very important outstanding
question for our understanding of the elusive neutrino and determination of the
mass ordering has consequences for other neutrino experiments. The JUNO reactor
experiment will start data taking this year, and the precision of the
atmospheric $\Delta m^2$'s from electron anti-neutrino measurements will
improve by a factor of three from Daya Bay's 2.4 % to 0.8 % within a year. This
measurement, when combined with the atmospheric $\Delta m^2$'s measurements
from T2K and NOvA for muon neutrino disappearance, will contribute
substantially to the $\Delta \chi^2$ between the two remaining neutrino mass
orderings. In this paper we derive a mass ordering sum rule that can be used to
address the possibility that JUNO's atmospheric $\Delta m^2$'s measurement,
when combined with other experiments in particular T2K and NOvA, can determine
the neutrino mass ordering at the 3 $\sigma$ confidence level within one year
of operation. For a confidence level of 5 $\sigma$ in a single experiment we
will have to wait until the middle of the next decade when the DUNE experiment
is operating.
| [
{
"created": "Fri, 12 Apr 2024 18:00:03 GMT",
"version": "v1"
}
] | 2024-04-16 | [
[
"Parke",
"Stephen J.",
""
],
[
"Funchal",
"Renata Zukanovich",
""
]
] | We revisit a method for determining the neutrino mass ordering by using precision measurements of the atmospheric $\Delta m^2$'s in both electron neutrino and muon neutrino disappearance channels, proposed by the authors in 2005 (hep-ph/0503283). The mass ordering is a very important outstanding question for our understanding of the elusive neutrino and determination of the mass ordering has consequences for other neutrino experiments. The JUNO reactor experiment will start data taking this year, and the precision of the atmospheric $\Delta m^2$'s from electron anti-neutrino measurements will improve by a factor of three from Daya Bay's 2.4 % to 0.8 % within a year. This measurement, when combined with the atmospheric $\Delta m^2$'s measurements from T2K and NOvA for muon neutrino disappearance, will contribute substantially to the $\Delta \chi^2$ between the two remaining neutrino mass orderings. In this paper we derive a mass ordering sum rule that can be used to address the possibility that JUNO's atmospheric $\Delta m^2$'s measurement, when combined with other experiments in particular T2K and NOvA, can determine the neutrino mass ordering at the 3 $\sigma$ confidence level within one year of operation. For a confidence level of 5 $\sigma$ in a single experiment we will have to wait until the middle of the next decade when the DUNE experiment is operating. |
hep-ph/9602331 | null | Thomas G. Rizzo | Z Anomalous Couplings and the Polarization Asymmetry in $\gamma e \to
Ze$ | 24 pages, 8 figures, uuencoded gz-compressed postscript file. To
obtain a copy of this paper send e-mail to techpub@slac.stanford.edu | Phys.Rev.D54:3057-3064,1996 | 10.1103/PhysRevD.54.3057 | SLAC-PUB-7109 | hep-ph | null | We extend our previous analysis of the sensitivity of the energy dependence
of the polarization asymmetry in $\gamma e \to W\nu$ to the possible existence
of anomalous trilinear gauge couplings to the $\gamma e \to Ze$ case. We find
that by combining the constraints imposed by both the energy dependence of the
total cross section and polarization asymmetry, strong limits on the anomalous
$\gamma ZZ$ couplings are obtainable at the Next Linear Collider. Further
constraints obtained from a consideration of the angular distribution are
briefly discussed.
| [
{
"created": "Fri, 16 Feb 1996 19:31:37 GMT",
"version": "v1"
}
] | 2009-12-30 | [
[
"Rizzo",
"Thomas G.",
""
]
] | We extend our previous analysis of the sensitivity of the energy dependence of the polarization asymmetry in $\gamma e \to W\nu$ to the possible existence of anomalous trilinear gauge couplings to the $\gamma e \to Ze$ case. We find that by combining the constraints imposed by both the energy dependence of the total cross section and polarization asymmetry, strong limits on the anomalous $\gamma ZZ$ couplings are obtainable at the Next Linear Collider. Further constraints obtained from a consideration of the angular distribution are briefly discussed. |
0910.3939 | Kuang-Ta Chao | Zhi-Guo He, Ying Fan, Kuang-Ta Chao | NRQCD Predictions of D-Wave Quarkonia $^3D_{J}(J=1,2,3)$ Decay into
Light Hadrons at Order $\alpha_{s}^{3}$ | 12 figures, references added, published version in PRD | Phys.Rev.D81:074032,2010 | 10.1103/PhysRevD.81.074032 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, in the framework of NRQCD we study the light hadron (LH)
decays of the spin-triplet (S=1) D-wave heavy quarkonia. The short distance
coefficients of all Fock states in the $^3D_J(J=1,2,3)$ quarkonia including
D-wave color-singlet, P-wave color-octet and S-wave color-singlet and
color-octet are calculated perturbatively at $\alpha_{s}^3$ order. The operator
evolution equations of the four-fermion operators are also derived and are used
to estimate the numerical values of the long distance matrix elements. We find
that for the $c\bar{c}$ system, the LH decay widths of $\psi(1^3D_J)$ predicted
by NRQCD is about $2\sim3$ times larger than the phenomenological potential
model results, while for the $b\bar{b}$ system the two theoretical estimations
of $\Gamma(\Upsilon(1^3D_J)\to LH)$ are in coincidence with each other. Our
predictions for $\psi(1^3D_J)$ LH decay widths are $\Gamma(\psi(1^3D_J)\to
LH)=(0.43,0.05,0.17)$MeV for J=1,2,3; and for $\Upsilon(1^3D_J)$,
$\Gamma(\Upsilon(1^3D_J)\to LH)=(6.91,0.75,2.75)$KeV for J=1,2,3.
| [
{
"created": "Tue, 20 Oct 2009 19:41:09 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Apr 2010 15:02:41 GMT",
"version": "v2"
}
] | 2010-05-12 | [
[
"He",
"Zhi-Guo",
""
],
[
"Fan",
"Ying",
""
],
[
"Chao",
"Kuang-Ta",
""
]
] | In this paper, in the framework of NRQCD we study the light hadron (LH) decays of the spin-triplet (S=1) D-wave heavy quarkonia. The short distance coefficients of all Fock states in the $^3D_J(J=1,2,3)$ quarkonia including D-wave color-singlet, P-wave color-octet and S-wave color-singlet and color-octet are calculated perturbatively at $\alpha_{s}^3$ order. The operator evolution equations of the four-fermion operators are also derived and are used to estimate the numerical values of the long distance matrix elements. We find that for the $c\bar{c}$ system, the LH decay widths of $\psi(1^3D_J)$ predicted by NRQCD is about $2\sim3$ times larger than the phenomenological potential model results, while for the $b\bar{b}$ system the two theoretical estimations of $\Gamma(\Upsilon(1^3D_J)\to LH)$ are in coincidence with each other. Our predictions for $\psi(1^3D_J)$ LH decay widths are $\Gamma(\psi(1^3D_J)\to LH)=(0.43,0.05,0.17)$MeV for J=1,2,3; and for $\Upsilon(1^3D_J)$, $\Gamma(\Upsilon(1^3D_J)\to LH)=(6.91,0.75,2.75)$KeV for J=1,2,3. |
0901.3463 | Yue Chongxing | Wei Liu, Chong-Xing Yue, Hui-Di Yang | Rare decays $B_s\to l^+l^-$ and $B\to Kl^+l^-$ in \the topcolor-assisted
technicolor model | 29 pages, 9 figure, corrected typos, the version to appear in PRD | Phys.Rev.D79:034008,2009 | 10.1103/PhysRevD.79.034008 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the rare decays $B_s\to l^+l^-$ and $B\to Kl^+l^-$ in the
framework of the topcolor-assisted technicolor ($TC2$) model. The contributions
of the new particles predicted by this model to these rare decay processes are
evaluated. We find that the values of their branching ratios are larger than
the standard model predictions by one order of magnitude in wide range of the
parameter space. The longitudinal polarization asymmetry of leptons in $B_s \to
l^+l^-$ can approach $\ord(10^{-2})$. The forward-backward asymmetry of leptons
in $B \to Kl^+l^-$ is not large enough to be measured in future experiments. We
also give some discussions about the branching ratios and the asymmetry
observables related to these rare decay processes in the littlest Higgs model
with T-parity.
| [
{
"created": "Thu, 22 Jan 2009 12:13:07 GMT",
"version": "v1"
},
{
"created": "Sun, 8 Feb 2009 12:16:53 GMT",
"version": "v2"
},
{
"created": "Sat, 30 May 2009 02:44:49 GMT",
"version": "v3"
}
] | 2014-11-18 | [
[
"Liu",
"Wei",
""
],
[
"Yue",
"Chong-Xing",
""
],
[
"Yang",
"Hui-Di",
""
]
] | We examine the rare decays $B_s\to l^+l^-$ and $B\to Kl^+l^-$ in the framework of the topcolor-assisted technicolor ($TC2$) model. The contributions of the new particles predicted by this model to these rare decay processes are evaluated. We find that the values of their branching ratios are larger than the standard model predictions by one order of magnitude in wide range of the parameter space. The longitudinal polarization asymmetry of leptons in $B_s \to l^+l^-$ can approach $\ord(10^{-2})$. The forward-backward asymmetry of leptons in $B \to Kl^+l^-$ is not large enough to be measured in future experiments. We also give some discussions about the branching ratios and the asymmetry observables related to these rare decay processes in the littlest Higgs model with T-parity. |
1412.6103 | Austin Purves | Burt A. Ovrut, Austin Purves and Sogee Spinner | A Statistical Analysis of the Minimal SUSY B-L Theory | 16 pages, 6 figures | Mod. Phys. Lett. A, Vol. 30, No. 18 (2015) 1550085 | 10.1142/S0217732315500856 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The structure of the B-L MSSM theory--specifically, the relevant mass scales
and soft supersymmetric breaking parameters--is discussed. The space of initial
soft parameters is explored at the high scale using random statistical sampling
subject to a constraint on the range of dimensionful parameters. For every
chosen initial point, the complete set of renormalization group equations is
solved. The low energy results are then constrained to be consistent with
present experimental data. It is shown that a large set of initial conditions
satisfy these constraints and lead to acceptable low energy particle physics.
Each such initial point has explicit predictions, such as the exact physical
sparticle spectrum--which is presented for two such points. There are also
statistical predictions for the masses of the sparticles and the LSP species
which are displayed as histograms. Finally, the fine-tuning of the $\mu$
parameter--which is always equivalent to or smaller than in the MSSM--is
discussed.
| [
{
"created": "Thu, 18 Dec 2014 21:00:12 GMT",
"version": "v1"
}
] | 2015-05-21 | [
[
"Ovrut",
"Burt A.",
""
],
[
"Purves",
"Austin",
""
],
[
"Spinner",
"Sogee",
""
]
] | The structure of the B-L MSSM theory--specifically, the relevant mass scales and soft supersymmetric breaking parameters--is discussed. The space of initial soft parameters is explored at the high scale using random statistical sampling subject to a constraint on the range of dimensionful parameters. For every chosen initial point, the complete set of renormalization group equations is solved. The low energy results are then constrained to be consistent with present experimental data. It is shown that a large set of initial conditions satisfy these constraints and lead to acceptable low energy particle physics. Each such initial point has explicit predictions, such as the exact physical sparticle spectrum--which is presented for two such points. There are also statistical predictions for the masses of the sparticles and the LSP species which are displayed as histograms. Finally, the fine-tuning of the $\mu$ parameter--which is always equivalent to or smaller than in the MSSM--is discussed. |
0904.1547 | Joerg Jaeckel | Joerg Jaeckel | Probing Minicharged Particles with Tests of Coulomb's Law | 10 pages, 1 figure | Phys.Rev.Lett.103:080402,2009 | 10.1103/PhysRevLett.103.080402 | IPPP/09/30; DCPT/09/60 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Minicharged particles arise in many extensions of the Standard Model. Their
contribution to the vacuum polarization modifies Coulomb's law via the Uehling
potential. In this note we argue that tests for electromagnetic fifth forces
can therefore be a sensitive probe of minicharged particles. In the low mass
range <~micro-eV existing constraints from Cavendish type experiments provide
the best model-independent bounds on minicharged particles.
| [
{
"created": "Thu, 9 Apr 2009 15:19:45 GMT",
"version": "v1"
}
] | 2009-09-02 | [
[
"Jaeckel",
"Joerg",
""
]
] | Minicharged particles arise in many extensions of the Standard Model. Their contribution to the vacuum polarization modifies Coulomb's law via the Uehling potential. In this note we argue that tests for electromagnetic fifth forces can therefore be a sensitive probe of minicharged particles. In the low mass range <~micro-eV existing constraints from Cavendish type experiments provide the best model-independent bounds on minicharged particles. |
hep-ph/9512277 | Gautam Bhattacharyya | Gautam Bhattacharyya and Amitava Raychaudhuri | Searching $R$-parity-violating supersymmetry in semileptonic $B$-decays | 12 pages, Latex, 3 uucompressed figures added through 'figures'
option | Phys.Lett. B374 (1996) 93-99 | 10.1016/0370-2693(96)00176-1 | CERN-TH/95-320, CUPP-95/7 | hep-ph | null | If $R$-parity is broken and the photino, although unstable, does not decay
within the detector, then in new semileptonic $B$-decay modes a light ($\sim$
2--3 GeV) photino can be produced carrying missing energy. However, the
photino, being massive, arranges a different kinematical configuration for the
visible decay products as compared to a standard semileptonic event where the
neutrino carries the missing energy. We study the above kinematic distributions
in an attempt to explore the above scenario.
| [
{
"created": "Mon, 11 Dec 1995 17:22:42 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Bhattacharyya",
"Gautam",
""
],
[
"Raychaudhuri",
"Amitava",
""
]
] | If $R$-parity is broken and the photino, although unstable, does not decay within the detector, then in new semileptonic $B$-decay modes a light ($\sim$ 2--3 GeV) photino can be produced carrying missing energy. However, the photino, being massive, arranges a different kinematical configuration for the visible decay products as compared to a standard semileptonic event where the neutrino carries the missing energy. We study the above kinematic distributions in an attempt to explore the above scenario. |
hep-ph/9911491 | D. R. T. Jones | I. Jack and D.R.T. Jones | Renormalisation of the Fayet-Iliopoulos D-term | 11 pages, TeX, Uses Harvmac (big). References added, minor
corrections (including a sign error for the zeta(3) terms), and discussion of
scheme dependence corrected and amplified | Phys.Lett. B473 (2000) 102-108 | 10.1016/S0370-2693(99)01484-7 | LTH 468 | hep-ph | null | We consider the renormalisation of the Fayet-Iliopoulos D-term in a
softly-broken Abelian supersymmetric theory. We show that there exists (at
least through three loops) a renormalisation group invariant trajectory for the
coefficient of the D-term, corresponding to the conformal anomaly solution for
the soft masses and couplings.
| [
{
"created": "Thu, 25 Nov 1999 16:08:10 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Nov 1999 16:50:12 GMT",
"version": "v2"
},
{
"created": "Wed, 22 Dec 1999 15:18:27 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Jack",
"I.",
""
],
[
"Jones",
"D. R. T.",
""
]
] | We consider the renormalisation of the Fayet-Iliopoulos D-term in a softly-broken Abelian supersymmetric theory. We show that there exists (at least through three loops) a renormalisation group invariant trajectory for the coefficient of the D-term, corresponding to the conformal anomaly solution for the soft masses and couplings. |
2201.00460 | Hai-Yang Cheng | Hai-Yang Cheng, Cheng-Wei Chiang, Zhi-Qing Zhang | Hadronic three-body D decays mediated by scalar resonances | 30 pages, 2 figures, references and discussions added, version
accepted by PRD | null | 10.1103/PhysRevD.105.033006 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the quasi-two-body $D\to SP$ decays and the three-body $D$ decays
proceeding through intermediate scalar resonances, where $S$ and $P$ denote
scalar and pseudoscalar mesons, respectively. Our main results are: (i) Certain
external and internal $W$-emission diagrams with the emitted meson being a
scalar meson are na{\"i}vely expected to vanish, but they actually receive
contributions from vertex and hard spectator-scattering corrections beyond the
factorization approximation. (ii) For light scalars with masses below or close
to 1~GeV, it is more sensible to study three-body decays directly and compare
with experiment as the two-body branching fractions are either unavailable or
subject to large finite-width effects of the scalar meson. (iii) We consider
the two-quark (scheme I) and four-quark (scheme II) descriptions of the light
scalar mesons, and find the latter generally in better agreement with
experiment. This is in line with recent BESIII measurements of semileptonic
charm decays that prefer the tetraquark description of light scalars produced
in charmed meson decays. (iv) The topological amplitude approach fails here as
the $D\to SP$ decay branching fractions cannot be reliably inferred from the
measurements of three-body decays, mainly because the decay rates cannot be
factorized into the topological amplitude squared and the phase space factor.
(v) The predicted rates for $D^0\to f_0 P, a_0 P$ are generally smaller than
experimental data by one order of magnitude, presumably implying the
significance of $W$-exchange amplitudes. (vi) The $W$-annihilation amplitude is
found to be very sizable in the $SP$ sector with $|A/T|_{SP}\sim 1/2$, contrary
to its suppression in the $PP$ sector with $|A/T|_{PP}\sim 0.18$.
| [
{
"created": "Mon, 3 Jan 2022 03:12:35 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Jan 2022 08:09:18 GMT",
"version": "v2"
}
] | 2022-03-14 | [
[
"Cheng",
"Hai-Yang",
""
],
[
"Chiang",
"Cheng-Wei",
""
],
[
"Zhang",
"Zhi-Qing",
""
]
] | We study the quasi-two-body $D\to SP$ decays and the three-body $D$ decays proceeding through intermediate scalar resonances, where $S$ and $P$ denote scalar and pseudoscalar mesons, respectively. Our main results are: (i) Certain external and internal $W$-emission diagrams with the emitted meson being a scalar meson are na{\"i}vely expected to vanish, but they actually receive contributions from vertex and hard spectator-scattering corrections beyond the factorization approximation. (ii) For light scalars with masses below or close to 1~GeV, it is more sensible to study three-body decays directly and compare with experiment as the two-body branching fractions are either unavailable or subject to large finite-width effects of the scalar meson. (iii) We consider the two-quark (scheme I) and four-quark (scheme II) descriptions of the light scalar mesons, and find the latter generally in better agreement with experiment. This is in line with recent BESIII measurements of semileptonic charm decays that prefer the tetraquark description of light scalars produced in charmed meson decays. (iv) The topological amplitude approach fails here as the $D\to SP$ decay branching fractions cannot be reliably inferred from the measurements of three-body decays, mainly because the decay rates cannot be factorized into the topological amplitude squared and the phase space factor. (v) The predicted rates for $D^0\to f_0 P, a_0 P$ are generally smaller than experimental data by one order of magnitude, presumably implying the significance of $W$-exchange amplitudes. (vi) The $W$-annihilation amplitude is found to be very sizable in the $SP$ sector with $|A/T|_{SP}\sim 1/2$, contrary to its suppression in the $PP$ sector with $|A/T|_{PP}\sim 0.18$. |
0810.4899 | Paul Frampton | David A. Eby, Paul H. Frampton and Shinya Matsuzaki | Predictions of Neutrino Mixing Angles in a T'Model | Typos. Reference added | Phys.Lett.B671:386-390,2009 | 10.1016/j.physletb.2008.11.074 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Flavor symmetry ($T^{'} \times Z_2$) where $T^{'}$ is the binary tetrahedral
group predicts for neutrino mixing angles $\theta_{13} = \sqrt{2}
(\frac{\pi}{4} - \theta_{23})$ and, with one phenomenological input, provides
upper and lower bounds on both $\theta_{13}$ and $\theta_{23}$. The predictions
arise from the deviation of the Cabibbo angle $\Theta_{12}$ from its
lowest-order value $\tan 2\Theta_{12} = (\sqrt{2})/3$ and from the $T^{'}$
mechanism which relates mixing of $(\nu_{\tau}, \nu_{\mu}, \nu_e)$ neutrinos to
mixing of $(s, d)$ quarks.
| [
{
"created": "Mon, 27 Oct 2008 18:37:00 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Nov 2008 18:26:34 GMT",
"version": "v2"
}
] | 2010-04-21 | [
[
"Eby",
"David A.",
""
],
[
"Frampton",
"Paul H.",
""
],
[
"Matsuzaki",
"Shinya",
""
]
] | Flavor symmetry ($T^{'} \times Z_2$) where $T^{'}$ is the binary tetrahedral group predicts for neutrino mixing angles $\theta_{13} = \sqrt{2} (\frac{\pi}{4} - \theta_{23})$ and, with one phenomenological input, provides upper and lower bounds on both $\theta_{13}$ and $\theta_{23}$. The predictions arise from the deviation of the Cabibbo angle $\Theta_{12}$ from its lowest-order value $\tan 2\Theta_{12} = (\sqrt{2})/3$ and from the $T^{'}$ mechanism which relates mixing of $(\nu_{\tau}, \nu_{\mu}, \nu_e)$ neutrinos to mixing of $(s, d)$ quarks. |
1707.00522 | Zhi-Long Han | Shu-Yuan Guo, Zhi-Long Han, Bin Li, Yi Liao, Xiao-Dong Ma | Interpreting the $R_{K^{(*)}}$ Anomaly in the Colored Zee-Babu Model | 16 pages, 6 figures, accepted by NPB | null | 10.1016/j.nuclphysb.2018.01.024 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the feasibility of interpreting the $R_{K^{(*)}}$ anomaly in the
colored Zee-Babu model. The model generates neutrino masses at two loops with
the help of a scalar leptoquark $S\sim(3,3,-\frac{1}{3})$ and a scalar diquark
$\omega\sim(6,1,-\frac{2}{3})$, and contributes to the transition $b\to
s\ell\ell$ via the exchange of a leptoquark $S$ at tree level. Under
constraints from lepton flavor violating (LFV) and flavor changing neutral
current (FCNC) processes, and direct collider searches for heavy particles, we
acquire certain parameter space that can accommodate the $R_{K^{(*)}}$ anomaly
for both normal (NH) and inverted (IH) hierarchies of neutrino masses. We
further examine the LFV decays of the $B$ meson, and find its strong
correlation with the neutrino mass hierarchy, i.e., $\text{Br}(B^+ \to K^+
\mu^\pm\tau^\mp)\gtrsim\text{Br}(B^+ \to K^+ \mu^\pm e^\mp)\approx\text{Br}(B^+
\to K^+ \tau^\pm e^\mp)$ for NH, while $\text{Br}(B^+ \to K^+ \mu^\pm
\tau^\mp)\ll\text{Br}(B^+ \to K^+ \mu^\pm e^\mp)\approx\text{Br}(B^+ \to K^+
\tau^\pm e^\mp)$ for IH. Among these decays, only $B^+ \to K^+ \mu^\pm e^\mp$
in the case of NH is promising at the LHCb RUN II, while for IH all LFV decays
are hard to detect in the near future.
| [
{
"created": "Mon, 3 Jul 2017 13:05:03 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Jul 2017 06:24:38 GMT",
"version": "v2"
},
{
"created": "Fri, 29 Sep 2017 06:28:11 GMT",
"version": "v3"
},
{
"created": "Fri, 2 Feb 2018 01:35:39 GMT",
"version": "v4"
}
] | 2018-03-14 | [
[
"Guo",
"Shu-Yuan",
""
],
[
"Han",
"Zhi-Long",
""
],
[
"Li",
"Bin",
""
],
[
"Liao",
"Yi",
""
],
[
"Ma",
"Xiao-Dong",
""
]
] | We consider the feasibility of interpreting the $R_{K^{(*)}}$ anomaly in the colored Zee-Babu model. The model generates neutrino masses at two loops with the help of a scalar leptoquark $S\sim(3,3,-\frac{1}{3})$ and a scalar diquark $\omega\sim(6,1,-\frac{2}{3})$, and contributes to the transition $b\to s\ell\ell$ via the exchange of a leptoquark $S$ at tree level. Under constraints from lepton flavor violating (LFV) and flavor changing neutral current (FCNC) processes, and direct collider searches for heavy particles, we acquire certain parameter space that can accommodate the $R_{K^{(*)}}$ anomaly for both normal (NH) and inverted (IH) hierarchies of neutrino masses. We further examine the LFV decays of the $B$ meson, and find its strong correlation with the neutrino mass hierarchy, i.e., $\text{Br}(B^+ \to K^+ \mu^\pm\tau^\mp)\gtrsim\text{Br}(B^+ \to K^+ \mu^\pm e^\mp)\approx\text{Br}(B^+ \to K^+ \tau^\pm e^\mp)$ for NH, while $\text{Br}(B^+ \to K^+ \mu^\pm \tau^\mp)\ll\text{Br}(B^+ \to K^+ \mu^\pm e^\mp)\approx\text{Br}(B^+ \to K^+ \tau^\pm e^\mp)$ for IH. Among these decays, only $B^+ \to K^+ \mu^\pm e^\mp$ in the case of NH is promising at the LHCb RUN II, while for IH all LFV decays are hard to detect in the near future. |
1209.0211 | Amol Upadhye | Amol Upadhye | Dark energy fifth forces in torsion pendulum experiments | 15 pages, 17 figures; matches version accepted by PRD | null | 10.1103/PhysRevD.86.102003 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The chameleon scalar field is a matter-coupled dark energy candidate whose
nonlinear self-interaction partially screens its fifth force at laboratory
scales. Nevertheless, small-scale experiments such as the torsion pendulum can
provide powerful constraints on chameleon models. Here we develop a simple
approximation for computing chameleon fifth forces in torsion pendulum
experiments such as Eot-Wash. We show that our approximation agrees well with
published constraints on the quartic chameleon, and we use it to extend these
constraints to a much wider range of models. Finally, we forecast the
constraints which will result from the next-generation Eot-Wash experiment, and
show that this experiment will exclude a wide range of quantum-stable models.
| [
{
"created": "Sun, 2 Sep 2012 20:04:12 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Oct 2012 22:58:16 GMT",
"version": "v2"
}
] | 2013-05-30 | [
[
"Upadhye",
"Amol",
""
]
] | The chameleon scalar field is a matter-coupled dark energy candidate whose nonlinear self-interaction partially screens its fifth force at laboratory scales. Nevertheless, small-scale experiments such as the torsion pendulum can provide powerful constraints on chameleon models. Here we develop a simple approximation for computing chameleon fifth forces in torsion pendulum experiments such as Eot-Wash. We show that our approximation agrees well with published constraints on the quartic chameleon, and we use it to extend these constraints to a much wider range of models. Finally, we forecast the constraints which will result from the next-generation Eot-Wash experiment, and show that this experiment will exclude a wide range of quantum-stable models. |
1911.03670 | Konstantin Toms | A. Danilina, N. Nikitin, K. Toms | Decays of charged $B$-mesons into three charged leptons and a neutrino | 24 pages, 24 figures | Phys. Rev. D 101, 096007 (2020) | 10.1103/PhysRevD.101.096007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of the Standard Model we present predictions for partial
widths, double and single differential distributions, and forward--backward
lepton asymmetries for four-leptonic decays $B^- \to \mu^+\mu^- {\bar \nu}_e\,
e^-$, $B^- \to e^+ e^- {\bar
\nu}_\mu\,\mu^-$, $B^- \to \mu^+ \mu^-{\bar \nu}_\mu\,\mu^-$, and $B^- \to
e^+ e^- {\bar \nu}_e\, e^-$. We consider the contributions of virtual photon
emission from the light and heavy quarks of the $B^-$--meson, and we include
bremsstrahlung of a virtual photon from the charged lepton in the final state.
We use the model of vector meson dominance for calculation of virtual photon
emission by the light quark of the $B^-$--meson and take into account the
isotopic correction.
| [
{
"created": "Sat, 9 Nov 2019 11:26:33 GMT",
"version": "v1"
}
] | 2020-05-20 | [
[
"Danilina",
"A.",
""
],
[
"Nikitin",
"N.",
""
],
[
"Toms",
"K.",
""
]
] | In the framework of the Standard Model we present predictions for partial widths, double and single differential distributions, and forward--backward lepton asymmetries for four-leptonic decays $B^- \to \mu^+\mu^- {\bar \nu}_e\, e^-$, $B^- \to e^+ e^- {\bar \nu}_\mu\,\mu^-$, $B^- \to \mu^+ \mu^-{\bar \nu}_\mu\,\mu^-$, and $B^- \to e^+ e^- {\bar \nu}_e\, e^-$. We consider the contributions of virtual photon emission from the light and heavy quarks of the $B^-$--meson, and we include bremsstrahlung of a virtual photon from the charged lepton in the final state. We use the model of vector meson dominance for calculation of virtual photon emission by the light quark of the $B^-$--meson and take into account the isotopic correction. |
2308.01353 | Alessandro Morandini | Alessandro Morandini, Torben Ferber, Felix Kahlhoefer | Reconstructing axion-like particles from beam dumps with
simulation-based inference | 34 pages, 18 figures, 2 columns, matches published version | Eur. Phys. J. C 84, 200 (2024) | 10.1140/epjc/s10052-024-12557-4 | TTP23-031, P3H-23-054 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Axion-like particles (ALPs) that decay into photon pairs pose a challenge for
experiments that rely on the construction of a decay vertex in order to search
for long-lived particles. This is particularly true for beam-dump experiments,
where the distance between the unknown decay position and the calorimeter can
be very large. In this work we use machine learning to explore the possibility
to reconstruct the ALP properties, in particular its mass and lifetime, from
such inaccurate observations. We use a simulation-based inference approach
based on conditional invertible neural networks to reconstruct the posterior
probability of the ALP parameters for a given set of events. We find that for
realistic angular and energy resolution, such a neural network significantly
outperforms parameter reconstruction from conventional high-level variables
while at the same time providing reliable uncertainty estimates. Moreover, the
neural network can quickly be re-trained for different detector properties,
making it an ideal framework for optimizing experimental design.
| [
{
"created": "Wed, 2 Aug 2023 18:00:13 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Jul 2024 14:07:25 GMT",
"version": "v2"
}
] | 2024-07-30 | [
[
"Morandini",
"Alessandro",
""
],
[
"Ferber",
"Torben",
""
],
[
"Kahlhoefer",
"Felix",
""
]
] | Axion-like particles (ALPs) that decay into photon pairs pose a challenge for experiments that rely on the construction of a decay vertex in order to search for long-lived particles. This is particularly true for beam-dump experiments, where the distance between the unknown decay position and the calorimeter can be very large. In this work we use machine learning to explore the possibility to reconstruct the ALP properties, in particular its mass and lifetime, from such inaccurate observations. We use a simulation-based inference approach based on conditional invertible neural networks to reconstruct the posterior probability of the ALP parameters for a given set of events. We find that for realistic angular and energy resolution, such a neural network significantly outperforms parameter reconstruction from conventional high-level variables while at the same time providing reliable uncertainty estimates. Moreover, the neural network can quickly be re-trained for different detector properties, making it an ideal framework for optimizing experimental design. |
1706.01336 | Vladimir V. Anisovich | V.V. Anisovich, M.A. Matveev, J. Nyiri, A.N. Semenova | Narrow pentaquarks as diquark-diquark-antiquark systems | null | Mod. Phys. Lett. A, Vol. 32, No. 29 (2017) 1750154 | 10.1142/S0217732317501541 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The diquark-diquark-antiquark model describes pentaquark states both in terms
of quarks and hadrons. The latest LHCb data for pentaquarks with open charm
emphasize the importance of hadron components in the structure of pentaquarks.
We discuss pentaquark states with hidden charm $P(\bar c cuud)$ and those with
open charm $P(\bar uussc)$ which were discovered recently in LHCb data ($J/\Psi
p$ and $\Xi_c^+ K^-$ spectra correspondingly). Considering the observed states
as members of the lowest (s-wave) multiplet we discuss the mass splitting of
states and the dumping of their widths.
| [
{
"created": "Mon, 5 Jun 2017 14:10:40 GMT",
"version": "v1"
},
{
"created": "Thu, 31 Aug 2017 15:31:20 GMT",
"version": "v2"
}
] | 2017-09-01 | [
[
"Anisovich",
"V. V.",
""
],
[
"Matveev",
"M. A.",
""
],
[
"Nyiri",
"J.",
""
],
[
"Semenova",
"A. N.",
""
]
] | The diquark-diquark-antiquark model describes pentaquark states both in terms of quarks and hadrons. The latest LHCb data for pentaquarks with open charm emphasize the importance of hadron components in the structure of pentaquarks. We discuss pentaquark states with hidden charm $P(\bar c cuud)$ and those with open charm $P(\bar uussc)$ which were discovered recently in LHCb data ($J/\Psi p$ and $\Xi_c^+ K^-$ spectra correspondingly). Considering the observed states as members of the lowest (s-wave) multiplet we discuss the mass splitting of states and the dumping of their widths. |
1308.0254 | Oscar Cata | Oscar Cata (LMU, Munich) | Recent developments in nonleptonic kaon decays | 10 pages, 1 figure. Based on a review talk given at the 2013 Kaon
Physics International Conference (KAON13) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I review the current status of nonleptonic kaon decays, placing special
emphasis on the recent theoretical progress. In particular, I concentrate on 3
points: (i) the improved determination of \epsilon_K, including both
perturbative and nonperturbative contributions; (ii) the efforts to tame (K ->
2\pi) transitions in lattice QCD; and (iii) the use of holographic methods to
solve the vector meson dominance puzzle in (K -> 3\pi).
| [
{
"created": "Thu, 1 Aug 2013 15:55:26 GMT",
"version": "v1"
}
] | 2013-08-02 | [
[
"Cata",
"Oscar",
"",
"LMU, Munich"
]
] | I review the current status of nonleptonic kaon decays, placing special emphasis on the recent theoretical progress. In particular, I concentrate on 3 points: (i) the improved determination of \epsilon_K, including both perturbative and nonperturbative contributions; (ii) the efforts to tame (K -> 2\pi) transitions in lattice QCD; and (iii) the use of holographic methods to solve the vector meson dominance puzzle in (K -> 3\pi). |
1609.06941 | Frank Wilczek | Frank Wilczek | Theory Vision, LHCP 2016 | 14 pages, 3 figures, invited talk at LHCP Conference, Lund, June
2016; PoS(LHCP2016)047. v2: Microscopic stylistic changes and typo
correction, added reference | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I give my perspective on promising directions for high energy physics in
coming years.
| [
{
"created": "Thu, 22 Sep 2016 12:35:32 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Oct 2016 07:49:40 GMT",
"version": "v2"
}
] | 2016-10-05 | [
[
"Wilczek",
"Frank",
""
]
] | I give my perspective on promising directions for high energy physics in coming years. |
1112.2813 | Sergey Goloskokov | S. V. Goloskokov (JINR Dubna) | Hard Meson Electroproduction And Twist-3 Effects | 6 pages, 7 figures, report at Workshop on High Energy Spin Physics
Dubna, Russia, 2011 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze light meson electroproduction within the handbag model. We study
cross sections and spin asymmetries for various mesons. The essential role of
the transversity $\tilde H_T$ and $\tilde E_T$ GPDs in electroproduction of
pseudoscalar mesons is found. Our results are in good agrement with experiment.
| [
{
"created": "Tue, 13 Dec 2011 07:53:27 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Dec 2012 06:09:19 GMT",
"version": "v2"
}
] | 2012-12-27 | [
[
"Goloskokov",
"S. V.",
"",
"JINR Dubna"
]
] | We analyze light meson electroproduction within the handbag model. We study cross sections and spin asymmetries for various mesons. The essential role of the transversity $\tilde H_T$ and $\tilde E_T$ GPDs in electroproduction of pseudoscalar mesons is found. Our results are in good agrement with experiment. |
1601.08033 | Oleksandr Tomalak | O. Tomalak | Two-photon exchange corrections in elastic electron-proton scattering | 9 pages, 4 figures, Contribution to the 53 International Winter
Meeting on Nuclear Physics. in PoS Bormio2015 (2015) 015 | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We apply a subtracted dispersion relation (DR) formalism with the aim to
improve predictions for the two-photon exchange (TPE) corrections to elastic
electron-proton scattering observables at small momentum transfers. We study
the formalism on the elastic TPE contribution in comparison with existing data
for unpolarized cross sections. We extend the general formalism of TPE to
elastic scattering with massive lepton and perform a numerical estimate of the
muon-proton scattering at low momentum transfer in view of the upcoming
muon-proton scattering experiment (MUSE). We study the influence of the
double-virtual Compton scattering (VVCS) subtraction function on the
unpolarized lepton-proton scattering cross-section. We show that the resulting
TPE correction is negligible in the electron-proton scattering and smaller than
planned uncertainties of the MUSE experiment for the subtraction functions
evaluated in chiral perturbation theory.
| [
{
"created": "Fri, 29 Jan 2016 10:26:09 GMT",
"version": "v1"
}
] | 2016-02-01 | [
[
"Tomalak",
"O.",
""
]
] | We apply a subtracted dispersion relation (DR) formalism with the aim to improve predictions for the two-photon exchange (TPE) corrections to elastic electron-proton scattering observables at small momentum transfers. We study the formalism on the elastic TPE contribution in comparison with existing data for unpolarized cross sections. We extend the general formalism of TPE to elastic scattering with massive lepton and perform a numerical estimate of the muon-proton scattering at low momentum transfer in view of the upcoming muon-proton scattering experiment (MUSE). We study the influence of the double-virtual Compton scattering (VVCS) subtraction function on the unpolarized lepton-proton scattering cross-section. We show that the resulting TPE correction is negligible in the electron-proton scattering and smaller than planned uncertainties of the MUSE experiment for the subtraction functions evaluated in chiral perturbation theory. |
1005.5122 | Suryanarayana V.S. Saraswatula | S V Suryanarayana | Gluon emission in Quark-Gluon Plasma | 7 pages, 12 figures | null | null | null | hep-ph hep-ex hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Gluon radiation is an important mechanism for parton energy loss as the
parton traverses the quark gluon plasma (QGP) medium. We studied the gluon
emission in QGP using AMY formalism. In the present work, we obtained gluon
emission amplitude {\bf F}({\bf h},p,k) function, which is a solution of the
integral equations describing gluon radiation including
Landau-Pomeranchuk-Migdal (LPM) effects, using iterations method. We define a
new dynamical scale for gluon emission denoted by $x$. The gluon emission rate
is obtained by integrating these amplitude function over {\bf h}. We show that
these obey a simple scaling in terms of this dynamical variable $x$. We define
the gluon emission function $g(x)$ for gluon radiation for the three processes
$g\rightarrow gg$, $q\rightarrow gq$ and $g\rightarrow q\bar{q}$. In terms of
this $g(x)$ function, the parton energy loss calculations, due to medium
induced gluon radiation, may become simplified.
| [
{
"created": "Thu, 27 May 2010 17:11:22 GMT",
"version": "v1"
}
] | 2010-05-28 | [
[
"Suryanarayana",
"S V",
""
]
] | Gluon radiation is an important mechanism for parton energy loss as the parton traverses the quark gluon plasma (QGP) medium. We studied the gluon emission in QGP using AMY formalism. In the present work, we obtained gluon emission amplitude {\bf F}({\bf h},p,k) function, which is a solution of the integral equations describing gluon radiation including Landau-Pomeranchuk-Migdal (LPM) effects, using iterations method. We define a new dynamical scale for gluon emission denoted by $x$. The gluon emission rate is obtained by integrating these amplitude function over {\bf h}. We show that these obey a simple scaling in terms of this dynamical variable $x$. We define the gluon emission function $g(x)$ for gluon radiation for the three processes $g\rightarrow gg$, $q\rightarrow gq$ and $g\rightarrow q\bar{q}$. In terms of this $g(x)$ function, the parton energy loss calculations, due to medium induced gluon radiation, may become simplified. |
hep-ph/0302051 | Matthias Steinhauser | Kay Bieri, Christoph Greub, Matthias Steinhauser | Fermionic NNLL corrections to b -> s \gamma | 38 pages, result extended to allow for an explicit photon energy
cut-off, appendix and references added, final result and conlclusions
unchanged | Phys.Rev.D67:114019,2003 | 10.1103/PhysRevD.67.114019 | BUTP-2003/03, DESY 03-013, version to be published in PRD | hep-ph | null | In this paper we take the first step towards a complete
next-to-next-to-leading logarithmic (NNLL) calculation of the inclusive decay
rate for $B \to X_s\gamma$. We consider the virtual corrections of order
$\alphas^2 n_f$ to the matrix elements of the operators ${O}_1$, ${O}_2$ and
${O}_8$ and evaluate the real and virtual contributions to ${O}_7$. These
corrections are expected to be numerically important. We observe a strong
cancelation between the contributions from the current-current operators and
$O_7$ and obtain, after applying naive non-abelianization, a reduction of the
branching ratio of 3.9% (for $\mu=3.0$ GeV) and an increase of 3.4% (for
$\mu=9.6$ GeV).
| [
{
"created": "Fri, 7 Feb 2003 06:52:39 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Jun 2003 11:08:59 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Bieri",
"Kay",
""
],
[
"Greub",
"Christoph",
""
],
[
"Steinhauser",
"Matthias",
""
]
] | In this paper we take the first step towards a complete next-to-next-to-leading logarithmic (NNLL) calculation of the inclusive decay rate for $B \to X_s\gamma$. We consider the virtual corrections of order $\alphas^2 n_f$ to the matrix elements of the operators ${O}_1$, ${O}_2$ and ${O}_8$ and evaluate the real and virtual contributions to ${O}_7$. These corrections are expected to be numerically important. We observe a strong cancelation between the contributions from the current-current operators and $O_7$ and obtain, after applying naive non-abelianization, a reduction of the branching ratio of 3.9% (for $\mu=3.0$ GeV) and an increase of 3.4% (for $\mu=9.6$ GeV). |
1307.0711 | Ivo de Medeiros Varzielas | Ivo de Medeiros Varzielas, Daniel Pidt | Towards realistic models of quark masses with geometrical CP violation | 4 pages, 2 figures. v2: accepted by J. Phys. G | null | 10.1088/0954-3899/41/2/025004 | DO-TH-13/18 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a model for quark masses and mixing, featuring geometrical CP
violation through a \Delta(27) triplet. By employing a single U(1)_F or Z_N
symmetry in addition to \Delta(27), we forbid all terms in the scalar potential
that would spoil the calculable phases the triple acquires. The quark sector is
realised by mimicking an existing scheme that reproduces the masses and CKM
mixing, with the extra symmetry enabling the hierarchies in the Yukawa
couplings through a Froggatt-Nielsen mechanism.
| [
{
"created": "Tue, 2 Jul 2013 14:12:18 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Feb 2014 13:13:26 GMT",
"version": "v2"
}
] | 2015-06-16 | [
[
"Varzielas",
"Ivo de Medeiros",
""
],
[
"Pidt",
"Daniel",
""
]
] | We present a model for quark masses and mixing, featuring geometrical CP violation through a \Delta(27) triplet. By employing a single U(1)_F or Z_N symmetry in addition to \Delta(27), we forbid all terms in the scalar potential that would spoil the calculable phases the triple acquires. The quark sector is realised by mimicking an existing scheme that reproduces the masses and CKM mixing, with the extra symmetry enabling the hierarchies in the Yukawa couplings through a Froggatt-Nielsen mechanism. |
1602.06448 | Aftab Ahmad | Aftab Ahmad and Alfredo Raya | Inverse magnetic catalysis and confinement within a contact interaction
model for quarks | 14 pages,10 Figures | J. Phys. G: Nucl. Part. Phys. 43 (2016) 065002 | 10.1088/0954-3899/43/6/065002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We evaluate the impact of an external magnetic field on the chiral symmetry
and confinement-deconfinement transition temperatures by using a vector-vector
contact interaction model for quarks regularized so as to include an explicit
confining scale in the corresponding gap equation. Exploring the evolution of
the chiral condensate and the confining scale with temperature $T$ and magnetic
field strength $eB$ ($e$ represents the fundamental electric charge), we
determine the pseudo-critical temperatures for the chiral ($T_c^\chi$) and
deconfinement ($T_c^c$) transitions from their inflection points, respectively.
By construction, $T_c^\chi= T_c^c$ in the chiral limit. Within a mean field
approximation, we observe the magnetic catalysis phenomenon, characterized by a
rising behavior of $T_c^\chi$ and $T_c^c$ with growing $eB$. Considering a
lattice inspired running coupling which monotonically decreases with $eB$,
inverse magnetic catalysis takes place in our model. We explore the role of the
magnetic field in the traits of the confinement-deconfinement transition
described by the model. Our findings are also in agreement with predictions
derived from effective models of strong interactions.
| [
{
"created": "Sat, 20 Feb 2016 20:11:44 GMT",
"version": "v1"
},
{
"created": "Tue, 17 May 2016 22:56:17 GMT",
"version": "v2"
}
] | 2016-05-19 | [
[
"Ahmad",
"Aftab",
""
],
[
"Raya",
"Alfredo",
""
]
] | We evaluate the impact of an external magnetic field on the chiral symmetry and confinement-deconfinement transition temperatures by using a vector-vector contact interaction model for quarks regularized so as to include an explicit confining scale in the corresponding gap equation. Exploring the evolution of the chiral condensate and the confining scale with temperature $T$ and magnetic field strength $eB$ ($e$ represents the fundamental electric charge), we determine the pseudo-critical temperatures for the chiral ($T_c^\chi$) and deconfinement ($T_c^c$) transitions from their inflection points, respectively. By construction, $T_c^\chi= T_c^c$ in the chiral limit. Within a mean field approximation, we observe the magnetic catalysis phenomenon, characterized by a rising behavior of $T_c^\chi$ and $T_c^c$ with growing $eB$. Considering a lattice inspired running coupling which monotonically decreases with $eB$, inverse magnetic catalysis takes place in our model. We explore the role of the magnetic field in the traits of the confinement-deconfinement transition described by the model. Our findings are also in agreement with predictions derived from effective models of strong interactions. |
2102.11551 | Gr\'egoire Uhlrich | G. Uhlrich, F. Mahmoudi, A. Arbey | Semi-automated BSM model building procedures in MARTY-1.1 through a 2HDM
example | Contribution to the proceedings of "Tools for High Energy Physics and
Cosmology" - TOOLS2020, 14 pages, 2 figures | PoS(TOOLS2020)042 | null | CERN-TH-2021-025 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | MARTY is a C++ computer algebra system specialized for High Energy Physics
that can calculate amplitudes, squared amplitudes and Wilson coefficients in a
large variety of beyond the Standard Model scenarios up to the one-loop order.
It is fully independent of any other framework and its main development
guideline is generality, in order to be adapted easily to any type of model.
The calculations are fully automated from the Lagrangian up to the generation
of the C++ code evaluating the theoretical results (numerically, depending on
the model parameters). Once a phenomenological tool chain has been set up -
from a Lagrangian to observable analysis - it can be used in a model
independent way leaving only model building, with MARTY, as the task to be
performed by physicists. Here we present the main steps to build a general new
physics model, namely gauge group, particle content, representations,
replacements, rotations and symmetry breaking, using the example of a 2 Higgs
Doublet Model. The sample codes that are shown for this example can be easily
generalized to any Beyond the Standard Model scenario written with MARTY.
| [
{
"created": "Tue, 23 Feb 2021 08:44:54 GMT",
"version": "v1"
}
] | 2021-02-24 | [
[
"Uhlrich",
"G.",
""
],
[
"Mahmoudi",
"F.",
""
],
[
"Arbey",
"A.",
""
]
] | MARTY is a C++ computer algebra system specialized for High Energy Physics that can calculate amplitudes, squared amplitudes and Wilson coefficients in a large variety of beyond the Standard Model scenarios up to the one-loop order. It is fully independent of any other framework and its main development guideline is generality, in order to be adapted easily to any type of model. The calculations are fully automated from the Lagrangian up to the generation of the C++ code evaluating the theoretical results (numerically, depending on the model parameters). Once a phenomenological tool chain has been set up - from a Lagrangian to observable analysis - it can be used in a model independent way leaving only model building, with MARTY, as the task to be performed by physicists. Here we present the main steps to build a general new physics model, namely gauge group, particle content, representations, replacements, rotations and symmetry breaking, using the example of a 2 Higgs Doublet Model. The sample codes that are shown for this example can be easily generalized to any Beyond the Standard Model scenario written with MARTY. |
hep-ph/9605344 | Gabriel Lopez Castro | J. L. Diaz-Cruz, G. Lopez Castro and J. H. Munoz | Isospin corrections to charmless semileptonic $B \to V$ transitions | Latex, 8 pages, no figures | Phys.Rev.D54:2388-2390,1996 | 10.1103/PhysRevD.54.2388 | CINVESTAV-FIS-01/96 | hep-ph | null | We compute isospin corrections to the charmless semileptonic $B \rightarrow
V$ transitions arising from $\rho-\omega$ mixing and discuss its relevance in
the determination of $V_{ub}$.
| [
{
"created": "Fri, 17 May 1996 18:14:31 GMT",
"version": "v1"
}
] | 2010-11-23 | [
[
"Diaz-Cruz",
"J. L.",
""
],
[
"Castro",
"G. Lopez",
""
],
[
"Munoz",
"J. H.",
""
]
] | We compute isospin corrections to the charmless semileptonic $B \rightarrow V$ transitions arising from $\rho-\omega$ mixing and discuss its relevance in the determination of $V_{ub}$. |
1410.8063 | Moritz Meinecke | J. Harz, B. Herrmann, M. Klasen, K. Kova\v{r}\'ik and M. Meinecke | SUSY-QCD corrections to stop annihilation into electroweak final states
including Coulomb enhancement effects | 20 pages, 13 figures, updated to version published in Phys. Rev. D | Phys. Rev. D 91, 034012 (2015) | 10.1103/PhysRevD.91.034012 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the full $\mathcal{O}(\alpha_s)$ supersymmetric QCD corrections
for stop-anti-stop annihilation into electroweak final states within the
Minimal Supersymmetric Standard Model (MSSM). We also incorporate Coulomb
corrections due to gluon exchange between the incoming stops. Numerical results
for the annihilation cross sections and the predicted neutralino relic density
are presented. We show that the impact of the radiative corrections on the
cosmologically preferred region of the parameter space can become larger than
the current experimental uncertainty, shifting the relic bands within the
considered regions of the parameter space by up to a few tens of GeV.
| [
{
"created": "Wed, 29 Oct 2014 17:18:29 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Nov 2014 09:41:38 GMT",
"version": "v2"
},
{
"created": "Mon, 17 Nov 2014 11:58:31 GMT",
"version": "v3"
},
{
"created": "Tue, 17 Feb 2015 22:44:19 GMT",
"version": "v4"
}
] | 2015-02-19 | [
[
"Harz",
"J.",
""
],
[
"Herrmann",
"B.",
""
],
[
"Klasen",
"M.",
""
],
[
"Kovařík",
"K.",
""
],
[
"Meinecke",
"M.",
""
]
] | We present the full $\mathcal{O}(\alpha_s)$ supersymmetric QCD corrections for stop-anti-stop annihilation into electroweak final states within the Minimal Supersymmetric Standard Model (MSSM). We also incorporate Coulomb corrections due to gluon exchange between the incoming stops. Numerical results for the annihilation cross sections and the predicted neutralino relic density are presented. We show that the impact of the radiative corrections on the cosmologically preferred region of the parameter space can become larger than the current experimental uncertainty, shifting the relic bands within the considered regions of the parameter space by up to a few tens of GeV. |
hep-ph/0609013 | Xiang Liu | Bo Zhang, Xiang Liu, Wei-Zhen Deng and Shi-Lin Zhu | $D_{sJ}(2860)$ and $D_{sJ}(2715)$ | 18 pages, 7 figures, 2 tables. Some discussions added. The final
version to appear at EPJC | Eur.Phys.J.C50:617-628,2007 | 10.1140/epjc/s10052-007-0221-y | null | hep-ph hep-ex | null | Recently Babar Collaboration reported a new $c\bar{s}$ state $D_{sJ}(2860)$
and Belle Collaboration observed $D_{sJ}(2715)$. We investigate the strong
decays of the excited $c\bar{s}$ states using the $^{3}P_{0}$ model. After
comparing the theoretical decay widths and decay patterns with the available
experimental data, we tend to conclude: (1) $D_{sJ}(2715)$ is probably the
$1^{-}(1^{3}D_{1})$ $c\bar{s}$ state although the $1^{-}(2^{3}S_{1})$
assignment is not completely excluded; (2) $D_{sJ}(2860)$ seems unlikely to be
the $1^{-}(2^{3}S_{1})$ and $1^{-}(1^{3}D_{1})$ candidate; (3) $D_{sJ}(2860)$
as either a $0^{+}(2^{3}P_{0})$ or $3^{-}(1^{3}D_{3})$ $c\bar{s}$ state is
consistent with the experimental data; (4) experimental search of
$D_{sJ}(2860)$ in the channels $D_s\eta$, $DK^{*}$, $D^{*}K$ and
$D_{s}^{*}\eta$ will be crucial to distinguish the above two possibilities.
| [
{
"created": "Mon, 4 Sep 2006 12:30:32 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Jan 2007 02:27:57 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Zhang",
"Bo",
""
],
[
"Liu",
"Xiang",
""
],
[
"Deng",
"Wei-Zhen",
""
],
[
"Zhu",
"Shi-Lin",
""
]
] | Recently Babar Collaboration reported a new $c\bar{s}$ state $D_{sJ}(2860)$ and Belle Collaboration observed $D_{sJ}(2715)$. We investigate the strong decays of the excited $c\bar{s}$ states using the $^{3}P_{0}$ model. After comparing the theoretical decay widths and decay patterns with the available experimental data, we tend to conclude: (1) $D_{sJ}(2715)$ is probably the $1^{-}(1^{3}D_{1})$ $c\bar{s}$ state although the $1^{-}(2^{3}S_{1})$ assignment is not completely excluded; (2) $D_{sJ}(2860)$ seems unlikely to be the $1^{-}(2^{3}S_{1})$ and $1^{-}(1^{3}D_{1})$ candidate; (3) $D_{sJ}(2860)$ as either a $0^{+}(2^{3}P_{0})$ or $3^{-}(1^{3}D_{3})$ $c\bar{s}$ state is consistent with the experimental data; (4) experimental search of $D_{sJ}(2860)$ in the channels $D_s\eta$, $DK^{*}$, $D^{*}K$ and $D_{s}^{*}\eta$ will be crucial to distinguish the above two possibilities. |
hep-ph/9701357 | Werner Bernreuther | Werner Bernreuther | CP vioation in weak decays and elsewhere | 15 pages, Latex | null | null | PITHA 97/3 | hep-ph | null | A brief overview is given on the status and prospects of searches for CP
nonconservation effects in weak decays of strange, charmed, and beauty hadrons,
on the search for permanent electric dipole moments of particles, and on
present and future high energy CP tests at colliders.
| [
{
"created": "Thu, 23 Jan 1997 13:20:59 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bernreuther",
"Werner",
""
]
] | A brief overview is given on the status and prospects of searches for CP nonconservation effects in weak decays of strange, charmed, and beauty hadrons, on the search for permanent electric dipole moments of particles, and on present and future high energy CP tests at colliders. |
hep-ph/0001081 | Sergei Chekanov | S. V. Chekanov, A. De Roeck, E. A. De Wolf | Bose-Einstein Correlations in e+e- -> W+W- at a Linear Collider | 5 pages, 2 eps figures, Proccedings of the Workshop "Physics Studies
for a Future Linear Collider", QCD Working Group, 2000, DESY 123F | null | null | ANL-HEP-CP-00-03 | hep-ph | null | We show that the most popular method to simulate Bose-Einstein (BE)
interference effects predicts negligible correlations between identical pions
originating from the hadronic decay of different W's produced in e+e- -> W+W-
-> 4 jets at typical linear collider energies.
| [
{
"created": "Tue, 11 Jan 2000 12:27:46 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Chekanov",
"S. V.",
""
],
[
"De Roeck",
"A.",
""
],
[
"De Wolf",
"E. A.",
""
]
] | We show that the most popular method to simulate Bose-Einstein (BE) interference effects predicts negligible correlations between identical pions originating from the hadronic decay of different W's produced in e+e- -> W+W- -> 4 jets at typical linear collider energies. |
2008.13616 | Raghunath Sahoo | Neelkamal Mallick, Raghunath Sahoo, Sushanta Tripathy, and Antonio
Ortiz | Study of Transverse Spherocity and Azimuthal Anisotropy in Pb-Pb
collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV using A Multi-Phase Transport
Model | Same as the published version. arXiv admin note: text overlap with
arXiv:2001.06849 | J. Phys. G: Nucl. Part. Phys. 48, 045104 (2021) | 10.1088/1361-6471/abeb59 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Transverse spherocity is an event shape observable having a very unique
capability to separate the events based on their geometrical shapes. Recent
results from experiments at the LHC suggest that transverse spherocity is an
important event classifier in small collision systems. In this work, we use
transverse spherocity for the first time in heavy-ion collisions and perform an
extensive study on azimuthal anisotropy of charged particles produced in Pb-Pb
collisions at $\sqrt{s_{\rm{NN}}} = 5.02$ TeV using A Multi-Phase Transport
Model (AMPT). The azimuthal anisotropy is estimated using the 2-particle
correlation method, which suppresses the non-flow effects significantly with an
appropriate pseudorapidity gap of particle pairs. The results from AMPT are
compared with estimations from PYTHIA8 (Angantyr) model and it is found that
with the chosen pseudorapidity gap the residual non-flow effects become
negligible. We found that the high spherocity events have nearly zero elliptic
flow while low spherocity events contribute significantly to elliptic flow of
spherocity-integrated events. Our studies indicate that using transverse
spherocity in heavy-ion collisions, one can enhance and/or suppress the
collective effects.
| [
{
"created": "Thu, 27 Aug 2020 18:10:46 GMT",
"version": "v1"
},
{
"created": "Fri, 2 Apr 2021 09:49:13 GMT",
"version": "v2"
}
] | 2021-04-05 | [
[
"Mallick",
"Neelkamal",
""
],
[
"Sahoo",
"Raghunath",
""
],
[
"Tripathy",
"Sushanta",
""
],
[
"Ortiz",
"Antonio",
""
]
] | Transverse spherocity is an event shape observable having a very unique capability to separate the events based on their geometrical shapes. Recent results from experiments at the LHC suggest that transverse spherocity is an important event classifier in small collision systems. In this work, we use transverse spherocity for the first time in heavy-ion collisions and perform an extensive study on azimuthal anisotropy of charged particles produced in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}} = 5.02$ TeV using A Multi-Phase Transport Model (AMPT). The azimuthal anisotropy is estimated using the 2-particle correlation method, which suppresses the non-flow effects significantly with an appropriate pseudorapidity gap of particle pairs. The results from AMPT are compared with estimations from PYTHIA8 (Angantyr) model and it is found that with the chosen pseudorapidity gap the residual non-flow effects become negligible. We found that the high spherocity events have nearly zero elliptic flow while low spherocity events contribute significantly to elliptic flow of spherocity-integrated events. Our studies indicate that using transverse spherocity in heavy-ion collisions, one can enhance and/or suppress the collective effects. |
hep-ph/0401033 | Ferruccio Feruglio | Ferruccio Feruglio | Extra Dimensions in Particle Physics | Talk given at the International Europhysics Conference on High Energy
Physics (July 17th-23rd 2003) Aachen, Germany; 16 pages, 10 figures | Eur.Phys.J.C33:s114-s128,2004 | 10.1140/epjcd/s2004-03-1699-8 | null | hep-ph hep-th | null | Current problems in particle physics are reviewed from the viewpoint of
theories possessing extra spatial dimensions.
| [
{
"created": "Wed, 7 Jan 2004 18:12:08 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Feruglio",
"Ferruccio",
""
]
] | Current problems in particle physics are reviewed from the viewpoint of theories possessing extra spatial dimensions. |
0711.3829 | Pietro Faccioli | M.C. Tichy and P. Faccioli | The Scalar Glueball in the Instanton Vacuum | Version accepted for publication on EPJ C | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the contribution of instantons to the binding and the mass of the
lightest scalar glueball, in gluondynamics. We show that the short-range
correlations introduced by such non-perturbative vacuum fluctuations are
sufficient to give raise to a scalar glueball bound-state, with mass in good
agreement with the results of recent lattice calculations.
| [
{
"created": "Sat, 24 Nov 2007 10:08:21 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Apr 2008 10:45:05 GMT",
"version": "v2"
},
{
"created": "Sat, 18 Jul 2009 20:47:53 GMT",
"version": "v3"
}
] | 2009-07-18 | [
[
"Tichy",
"M. C.",
""
],
[
"Faccioli",
"P.",
""
]
] | We study the contribution of instantons to the binding and the mass of the lightest scalar glueball, in gluondynamics. We show that the short-range correlations introduced by such non-perturbative vacuum fluctuations are sufficient to give raise to a scalar glueball bound-state, with mass in good agreement with the results of recent lattice calculations. |
1809.06353 | Fayez Abu-Ajamieh | Fayez M. Abu-Ajamieh | 4-Gluon Vertex Splitting Function and Jet Observables | The results are have errors. The paper needs fixing as the results
are not reliable | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I generalize the Altarelli-Parisi approach to finding the QCD splitting
functions to the case of 4-vertex interactions. I apply the results to the
4-gluon interaction and use them to define several jet observables. I estimate
the correction associated with the 4-gluon interaction compared with QCD
3-vertex interactions, and find that such a correction can be significant,
especially at low energies. For instance, it is estimated that at energy scales
between 100 GeV and 1 TeV, the corrections associated with the 4-g vertex could
range between ~ 6% - 10%, however, the correction becomes smaller at the TeV
scale and 3-vertex interactions become significantly more dominant.
| [
{
"created": "Mon, 17 Sep 2018 17:43:49 GMT",
"version": "v1"
},
{
"created": "Sun, 21 Oct 2018 17:42:35 GMT",
"version": "v2"
},
{
"created": "Tue, 23 Oct 2018 02:03:55 GMT",
"version": "v3"
}
] | 2018-10-24 | [
[
"Abu-Ajamieh",
"Fayez M.",
""
]
] | I generalize the Altarelli-Parisi approach to finding the QCD splitting functions to the case of 4-vertex interactions. I apply the results to the 4-gluon interaction and use them to define several jet observables. I estimate the correction associated with the 4-gluon interaction compared with QCD 3-vertex interactions, and find that such a correction can be significant, especially at low energies. For instance, it is estimated that at energy scales between 100 GeV and 1 TeV, the corrections associated with the 4-g vertex could range between ~ 6% - 10%, however, the correction becomes smaller at the TeV scale and 3-vertex interactions become significantly more dominant. |
2210.01280 | A. Bashir | L. Albino, A. Bashir, A.J. Mizher, A. Raya | Electron-Photon Vertex and Dynamical Chiral Symmetry Breaking in Reduced
QED: An Advanced Study of Gauge Invariance | 11 pages, 7 figures | null | 10.1103/PhysRevD.106.096007 | null | hep-ph cond-mat.str-el hep-th | http://creativecommons.org/licenses/by/4.0/ | We study the effect of a refined electron-photon vertex on the dynamical
breaking of chiral symmetry in reduced quantum electrodynamics. We construct an
educated {\em ansatz} for this vertex which satisfies the required discrete
symmetries under parity, time reversal and charge conjugation operations.
Furthermore, it reproduces its asymptotic perturbative limit in the weak
coupling regime and ensures the massless electron propagator is
multiplicatively renormalizable in its leading logarithmic expansion. Employing
this vertex {\em ansatz}, we solve the gap equation to compute dynamically
generated electron mass whose dependence on the electromagnetic coupling is
found to satisfy Miransky scaling law. We also investigate the gauge dependence
of this dynamical mass as well as that of the critical coupling above which
chiral symmetry is dynamically broken. As a litmus test of our vertex
construction, both these quantities are rendered virtually gauge independent
within a certain interval of values considered for the covariant gauge
parameter.
| [
{
"created": "Tue, 4 Oct 2022 00:02:00 GMT",
"version": "v1"
}
] | 2022-11-23 | [
[
"Albino",
"L.",
""
],
[
"Bashir",
"A.",
""
],
[
"Mizher",
"A. J.",
""
],
[
"Raya",
"A.",
""
]
] | We study the effect of a refined electron-photon vertex on the dynamical breaking of chiral symmetry in reduced quantum electrodynamics. We construct an educated {\em ansatz} for this vertex which satisfies the required discrete symmetries under parity, time reversal and charge conjugation operations. Furthermore, it reproduces its asymptotic perturbative limit in the weak coupling regime and ensures the massless electron propagator is multiplicatively renormalizable in its leading logarithmic expansion. Employing this vertex {\em ansatz}, we solve the gap equation to compute dynamically generated electron mass whose dependence on the electromagnetic coupling is found to satisfy Miransky scaling law. We also investigate the gauge dependence of this dynamical mass as well as that of the critical coupling above which chiral symmetry is dynamically broken. As a litmus test of our vertex construction, both these quantities are rendered virtually gauge independent within a certain interval of values considered for the covariant gauge parameter. |
hep-ph/0612313 | Tomislav Prokopec | Sietse van der Post, Tomislav Prokopec (Utrecht University) | Baryogenesis in Brans-Dicke theory | 12 pages, 2 figures | null | null | ITP-UU-06/53, SPIN-06/43 | hep-ph astro-ph gr-qc hep-th | null | A new mechanism for baryogenesis is proposed in the context of an extended
Brans-Dicke (BD) theory. We generalize the BD scalar to complex field with CP
violating coupling to curvature and show that the charged BD current can be
enhanced during inflationary epoch. After inflation the current decays (via
tree level interactions) into the standard model particles. When the BD scalar
is charged under baryon and/or lepton number, the decay produces a net baryon
number. Rather generically a sufficiently large scalar current can be produced
during inflation to account for the observed baryon asymmetry of the Universe.
Our baryogensis scenario can in an elegant way be incorporated into a model of
extended inflation.
| [
{
"created": "Fri, 22 Dec 2006 19:06:09 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"van der Post",
"Sietse",
"",
"Utrecht University"
],
[
"Prokopec",
"Tomislav",
"",
"Utrecht University"
]
] | A new mechanism for baryogenesis is proposed in the context of an extended Brans-Dicke (BD) theory. We generalize the BD scalar to complex field with CP violating coupling to curvature and show that the charged BD current can be enhanced during inflationary epoch. After inflation the current decays (via tree level interactions) into the standard model particles. When the BD scalar is charged under baryon and/or lepton number, the decay produces a net baryon number. Rather generically a sufficiently large scalar current can be produced during inflation to account for the observed baryon asymmetry of the Universe. Our baryogensis scenario can in an elegant way be incorporated into a model of extended inflation. |
1306.3556 | Weijian Wang | Weijian Wang | Neutrino mass textures with one vanishing minor and two equal cofactors | 18 pages, 2 figures | Eur.Phys.J.C,73(2013) 2551 | 10.1140/epjc/s10052-013-2551-2 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we carry out a numerical and systematic analysis of the
neutrino mass textures, which contain one vanishing minor and an equality
between two cofactors. Among 60 logically possible textures, only eight of them
are excluded for both normal and inverted hierarchy by the current experimental
data at 3\sigma level. We also demonstrate that the future long-baseline
neutrino oscillation experiments, especially for the measurement of \theta 23
mixing angle, will play the important role in the model selection. The
phenomenological implications from neutrinoless double beta decay and the
cosmology observation are also examined. A discussion on the flavor symmetry
realization of the textures is also given.
| [
{
"created": "Sat, 15 Jun 2013 08:22:53 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Aug 2013 00:00:45 GMT",
"version": "v2"
},
{
"created": "Tue, 20 May 2014 03:28:18 GMT",
"version": "v3"
}
] | 2014-05-21 | [
[
"Wang",
"Weijian",
""
]
] | In this paper, we carry out a numerical and systematic analysis of the neutrino mass textures, which contain one vanishing minor and an equality between two cofactors. Among 60 logically possible textures, only eight of them are excluded for both normal and inverted hierarchy by the current experimental data at 3\sigma level. We also demonstrate that the future long-baseline neutrino oscillation experiments, especially for the measurement of \theta 23 mixing angle, will play the important role in the model selection. The phenomenological implications from neutrinoless double beta decay and the cosmology observation are also examined. A discussion on the flavor symmetry realization of the textures is also given. |
2305.02218 | Fa Peng Huang | Siyu Jiang, Fa Peng Huang, and Chong Sheng Li | Hydrodynamic effects on the filtered dark matter produced by a
first-order phase transition | Published version in Physical Review D, 39 pages, 13 figures, 4
tables | Phys. Rev. D 108, 063508(2023) | 10.1103/PhysRevD.108.063508 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Motivated by current status of dark matter (DM) search, a new type of DM
production mechanism is proposed based on thedynamical process of a strong
first-order phase transition in the early universe, namely, the filtered DM
mechanism. We study the hydrodynamic effects on the DM relic density. By
detailed calculations, we demonstrate that the hydrodynamic modes with the
corresponding hydrodynamic heating effects play essential roles in determining
the DM relic density. The corresponding phase transition gravitational wave
could help to probe this new mechanism.
| [
{
"created": "Wed, 3 May 2023 15:56:10 GMT",
"version": "v1"
},
{
"created": "Mon, 12 Jun 2023 15:39:28 GMT",
"version": "v2"
},
{
"created": "Mon, 11 Sep 2023 15:42:05 GMT",
"version": "v3"
}
] | 2023-09-12 | [
[
"Jiang",
"Siyu",
""
],
[
"Huang",
"Fa Peng",
""
],
[
"Li",
"Chong Sheng",
""
]
] | Motivated by current status of dark matter (DM) search, a new type of DM production mechanism is proposed based on thedynamical process of a strong first-order phase transition in the early universe, namely, the filtered DM mechanism. We study the hydrodynamic effects on the DM relic density. By detailed calculations, we demonstrate that the hydrodynamic modes with the corresponding hydrodynamic heating effects play essential roles in determining the DM relic density. The corresponding phase transition gravitational wave could help to probe this new mechanism. |
2006.13872 | Ligong Bian | Ruiyu Zhou, Ligong Bian | Gravitational waves from cosmic strings and first-order phase transition | 14 pages, 1 figures, comments welcome! | null | null | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Cosmic strings and first-order phase transition are two main sources for the
stochastic gravitational wave background (SGWB). In this work, we study the
stochastic gravitational wave radiation from cosmic string which is formed
after the first-order phase transition. For the first-order phase transition
occurs at temperature far beyond the electroweak scale, the gravitational wave
signal cannot be reached by the future gravitational wave interferometers. The
gravitational waves from cosmic strings that formed after the phase transition
can be detected by future gravitational wave detectors in a wide range of
frequency, and therefore its imprints can serve to search for firs-order phase
transitions at high scales with the phase transition temperature: $
\mathcal{O}(10^8)$ GeV $ \leq T_n$ $\leq \mathcal{O}(10^{11})$ GeV.
| [
{
"created": "Wed, 24 Jun 2020 16:54:37 GMT",
"version": "v1"
}
] | 2020-06-25 | [
[
"Zhou",
"Ruiyu",
""
],
[
"Bian",
"Ligong",
""
]
] | Cosmic strings and first-order phase transition are two main sources for the stochastic gravitational wave background (SGWB). In this work, we study the stochastic gravitational wave radiation from cosmic string which is formed after the first-order phase transition. For the first-order phase transition occurs at temperature far beyond the electroweak scale, the gravitational wave signal cannot be reached by the future gravitational wave interferometers. The gravitational waves from cosmic strings that formed after the phase transition can be detected by future gravitational wave detectors in a wide range of frequency, and therefore its imprints can serve to search for firs-order phase transitions at high scales with the phase transition temperature: $ \mathcal{O}(10^8)$ GeV $ \leq T_n$ $\leq \mathcal{O}(10^{11})$ GeV. |
0712.2954 | Rumin Wang | C. S. Kim, Ru-Min Wang | Study of the exclusive $b \to u \ell^- \bar{\nu}_{\ell}$ decays in the
MSSM with and without R-parity violation | 28 pages and 10 figures | Phys.Rev.D77:094006,2008 | 10.1103/PhysRevD.77.094006 | null | hep-ph | null | We study the exclusive $b \to u \ell^- \bar{\nu}_{\ell} (\ell=\tau,\mu,e)$
decays in the MSSM with and without R-parity violation. From the experimental
measurements of branching ratios $\mathcal{B}(B^-_u \to \tau^-
\bar{\nu}_{\tau})$, $\mathcal{B}(B^-_u \to M'^0 \ell'^- \bar{\nu}_{\ell'})$ and
$\mathcal{B}(\bar{B}^0_d \to M'^+ \ell'^- \bar{\nu}_{\ell'})$ $(\ell'=\mu,e,
M'=\pi,\rho)$, we derive new upper bounds on the relevant new physics
parameters within the decays. Using the constrained new physics parameter
spaces, we predict the charged Higgs effects and the R-parity violating effects
on the branching ratios, the normalized forward-backward asymmetries of charged
leptons, and the ratios of longitudinal to transverse polarization of the
vector mesons, which have not been measured or have not been well measured yet.
We find that the charged Higgs effects and the R-parity violating effects could
be large and measurable in some cases. Our results could be used to probe new
physics effects in the leptonic decays as well as the semileptonic decays, and
will correlate with searches for direct supersymmetric signals in future
experiments.
| [
{
"created": "Tue, 18 Dec 2007 13:19:55 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Kim",
"C. S.",
""
],
[
"Wang",
"Ru-Min",
""
]
] | We study the exclusive $b \to u \ell^- \bar{\nu}_{\ell} (\ell=\tau,\mu,e)$ decays in the MSSM with and without R-parity violation. From the experimental measurements of branching ratios $\mathcal{B}(B^-_u \to \tau^- \bar{\nu}_{\tau})$, $\mathcal{B}(B^-_u \to M'^0 \ell'^- \bar{\nu}_{\ell'})$ and $\mathcal{B}(\bar{B}^0_d \to M'^+ \ell'^- \bar{\nu}_{\ell'})$ $(\ell'=\mu,e, M'=\pi,\rho)$, we derive new upper bounds on the relevant new physics parameters within the decays. Using the constrained new physics parameter spaces, we predict the charged Higgs effects and the R-parity violating effects on the branching ratios, the normalized forward-backward asymmetries of charged leptons, and the ratios of longitudinal to transverse polarization of the vector mesons, which have not been measured or have not been well measured yet. We find that the charged Higgs effects and the R-parity violating effects could be large and measurable in some cases. Our results could be used to probe new physics effects in the leptonic decays as well as the semileptonic decays, and will correlate with searches for direct supersymmetric signals in future experiments. |
2407.15606 | Yigal Shamir | Maarten Golterman and Yigal Shamir | Power counting of the pion-dilaton effective field theory | RevTeX, 17 pages | null | null | null | hep-ph hep-lat | http://creativecommons.org/licenses/by/4.0/ | Confining QCD-like theories close to the conformal window have a ``walking''
coupling. This is believed to lead to a light singlet scalar meson in the
low-energy spectrum, a dilaton, which is the pseudo Nambu--Goldstone boson for
the approximate scale symmetry. Extending chiral perturbation theory to include
the dilaton requires a new small parameter to control the dilaton mass and its
interactions. In our previous work we derived a systematic power counting for
the dilaton couplings by matching the effective low-energy theory to the
underlying theory using mild assumptions. In this paper we examine two
alternative power countings which were proposed in the literature based on a
phenomenological picture for the conformal transition. We find that one of
these power countings fails, in fact, to generate a systematic expansion; the
other coincides with the power counting we derived. We also point out that the
so-called $\Delta$-potential coincides with the tree-level potential of the
former, invalid, power counting.
| [
{
"created": "Mon, 22 Jul 2024 13:03:35 GMT",
"version": "v1"
}
] | 2024-07-23 | [
[
"Golterman",
"Maarten",
""
],
[
"Shamir",
"Yigal",
""
]
] | Confining QCD-like theories close to the conformal window have a ``walking'' coupling. This is believed to lead to a light singlet scalar meson in the low-energy spectrum, a dilaton, which is the pseudo Nambu--Goldstone boson for the approximate scale symmetry. Extending chiral perturbation theory to include the dilaton requires a new small parameter to control the dilaton mass and its interactions. In our previous work we derived a systematic power counting for the dilaton couplings by matching the effective low-energy theory to the underlying theory using mild assumptions. In this paper we examine two alternative power countings which were proposed in the literature based on a phenomenological picture for the conformal transition. We find that one of these power countings fails, in fact, to generate a systematic expansion; the other coincides with the power counting we derived. We also point out that the so-called $\Delta$-potential coincides with the tree-level potential of the former, invalid, power counting. |
hep-ph/0208192 | Armen Oganesian | B.L.Ioffe (ITEP) and A.G.Oganesian (ITEP) | Valence quark distributions in nucleon at low $Q^2$ in QCD | 22 pages, LaTeX 2e, 9 eps figures included, revised version (no
changes in text, only 1 LATEX command is changed) | Nucl.Phys. A714 (2003) 145-160 | 10.1016/S0375-9474(02)01322-2 | null | hep-ph | null | Valence u- and d-quarks distributions in proton are calculated in QCD at low
$Q^2$ and intermediate x, basing on the operator product expansion (OPE). The
imaginary part of the virtual photon scattering amplitude on quark current with
proton quantum numbers is considered. The initial and final virtualities
$p^2_1$ and $p^2_2$ of the currents are assumed to be large, negative and
different, $p^2_1 \not= p^2_2$. The OPE in $p^2_1$, $p^2_2$ up to dimension 6
operators was performed. Double dispersion representations in $p^2_1, p^2_2$ of
the amplitudes in terms of physical states contributions are used. Putting them
to be equal to those calculated in QCD, the sum rules for quark distributions
are found. The double Borel transformations are applied to the sum rules.
Leading order perturbative corrections are accounted. Valence quark
distributions are found: $u(x)_v$ at $0.15<x<65$,~ $d(x)_v$ at $0.25<x<0.55$
with an accuracy $\sim 30%$ in the middles and $\sim 50%$ at the ends of these
intervals. The quark distributions obtained are in agreement with those found
from the analysis of hard processes data.
| [
{
"created": "Wed, 21 Aug 2002 15:39:20 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Aug 2002 09:10:59 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Ioffe",
"B. L.",
"",
"ITEP"
],
[
"Oganesian",
"A. G.",
"",
"ITEP"
]
] | Valence u- and d-quarks distributions in proton are calculated in QCD at low $Q^2$ and intermediate x, basing on the operator product expansion (OPE). The imaginary part of the virtual photon scattering amplitude on quark current with proton quantum numbers is considered. The initial and final virtualities $p^2_1$ and $p^2_2$ of the currents are assumed to be large, negative and different, $p^2_1 \not= p^2_2$. The OPE in $p^2_1$, $p^2_2$ up to dimension 6 operators was performed. Double dispersion representations in $p^2_1, p^2_2$ of the amplitudes in terms of physical states contributions are used. Putting them to be equal to those calculated in QCD, the sum rules for quark distributions are found. The double Borel transformations are applied to the sum rules. Leading order perturbative corrections are accounted. Valence quark distributions are found: $u(x)_v$ at $0.15<x<65$,~ $d(x)_v$ at $0.25<x<0.55$ with an accuracy $\sim 30%$ in the middles and $\sim 50%$ at the ends of these intervals. The quark distributions obtained are in agreement with those found from the analysis of hard processes data. |
hep-ph/9905449 | J. R. Fleitas | J.Bellandi, J.R.Fleitas, J.Dias de Deus | Leading nucleon and the proton-nucleus inelasticity | 4 pages, 2 figures | null | null | null | hep-ph | null | We present in this paper a calculation of the average proton-nucleus
inelasticity. Using an Iterative Leading Particle Model and the Glauber model,
we relate the leading particle distribution in nucleon-nucleus interactions
with the respective one in nucleon- proton collisions. To describe the leading
particle distribution in nucleon-proton collisions, we use the Regge Mueller
formalism.
Contribution to 26th ICRC - Salt Lake City, Utah. August, 1999.
HE 1.1.14
| [
{
"created": "Fri, 21 May 1999 19:24:59 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bellandi",
"J.",
""
],
[
"Fleitas",
"J. R.",
""
],
[
"de Deus",
"J. Dias",
""
]
] | We present in this paper a calculation of the average proton-nucleus inelasticity. Using an Iterative Leading Particle Model and the Glauber model, we relate the leading particle distribution in nucleon-nucleus interactions with the respective one in nucleon- proton collisions. To describe the leading particle distribution in nucleon-proton collisions, we use the Regge Mueller formalism. Contribution to 26th ICRC - Salt Lake City, Utah. August, 1999. HE 1.1.14 |
1506.08468 | Matt Severson | Matthew Severson | Neutrino Sector and Proton Lifetime in a Realistic SUSY SO(10) Model | 51 pages, 9 figures, 7 tables, 1 appendix; v2 - added references in
Section I, updated eqs. (18), (20), and (30) for clarity and consistency; v3
- addressed minor concerns from referee, reconsidered timeline for model
testing, updated notation in eqs. (39) and (40) for consistency, addressed
some formatting difficulties present in previous versions | Phys. Rev. D 92, 095026 (2015) | 10.1103/PhysRevD.92.095026 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work I present a full analysis of proton decay in an $SO(10)$ model
previously proposed by Dutta, Mimura, and Mohapatra. The $\bf{10}$,
$\overline{\bf{126}}$, and $\bf{120}$ Yukawa couplings contributing to fermion
masses in this model have well-motivated restrictions on their textures
intended to give favorable results for proton lifetime as well as a realistic
fermion sector without the need for fine-tuning and for either type-I or
type-II dominance in the neutrino mass matrix. I obtain a valid fit for the
entire fermion sector for both types of seesaw dominance, including
$\theta_{13}$ in good agreement with the most recent data. For the case with
type-II seesaw, I find that using the Yukawa couplings fixed by the successful
fermion sector fit, proton partial lifetime limits are satisfied for nearly
every pertinent decay mode, even for nearly arbitrary values of the triplet
Higgs mixing parameters, with only the $K^+ \bar\nu$ mode requiring a minor
${\cal O}(10^{-1})$ cancellation in order to satisfy the experimental limit. I
also find a maximum lifetime for that mode of $\tau(K^+ \bar\nu) \sim 10^{36}$
years, which should be tested by eventual experiments. For the type-I seesaw
case, I find that all six pertinent decay modes of interest are satisfied for
values of the triplet mixing parameters giving no major enhancement, with modes
other than $K^+ \bar\nu$ easily satisfied for arbitrary mixing values, and with
a maximum lifetime for $K^+ \bar\nu$ of nearly $10^{38}$ years.
| [
{
"created": "Sun, 28 Jun 2015 22:56:08 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Jul 2015 20:29:45 GMT",
"version": "v2"
},
{
"created": "Mon, 19 Oct 2015 18:26:00 GMT",
"version": "v3"
}
] | 2015-12-09 | [
[
"Severson",
"Matthew",
""
]
] | In this work I present a full analysis of proton decay in an $SO(10)$ model previously proposed by Dutta, Mimura, and Mohapatra. The $\bf{10}$, $\overline{\bf{126}}$, and $\bf{120}$ Yukawa couplings contributing to fermion masses in this model have well-motivated restrictions on their textures intended to give favorable results for proton lifetime as well as a realistic fermion sector without the need for fine-tuning and for either type-I or type-II dominance in the neutrino mass matrix. I obtain a valid fit for the entire fermion sector for both types of seesaw dominance, including $\theta_{13}$ in good agreement with the most recent data. For the case with type-II seesaw, I find that using the Yukawa couplings fixed by the successful fermion sector fit, proton partial lifetime limits are satisfied for nearly every pertinent decay mode, even for nearly arbitrary values of the triplet Higgs mixing parameters, with only the $K^+ \bar\nu$ mode requiring a minor ${\cal O}(10^{-1})$ cancellation in order to satisfy the experimental limit. I also find a maximum lifetime for that mode of $\tau(K^+ \bar\nu) \sim 10^{36}$ years, which should be tested by eventual experiments. For the type-I seesaw case, I find that all six pertinent decay modes of interest are satisfied for values of the triplet mixing parameters giving no major enhancement, with modes other than $K^+ \bar\nu$ easily satisfied for arbitrary mixing values, and with a maximum lifetime for $K^+ \bar\nu$ of nearly $10^{38}$ years. |
0704.1355 | Xavier Calmet | Xavier Calmet and Martin Kober | Lowest Landau Level of Relativistic Field Theories in a Strong
Background Field | Submitted for the SUSY07 proceedings,4 pages | Proceedings of the 15th International Conference on Supersymmetry
and the Unification of Fundamental Interactions (SUSY 07). Eds. W. de Boer
and I. Gebauer, Vol. II, pp. 702-705, 2008 | null | null | hep-ph astro-ph hep-th | null | We consider gauge theories in a strong external magnetic like field. This
situation can appear either in conventional four-dimensional theories, but also
naturally in extra-dimensional theories and especially in brane world models.
We show that in the lowest Landau level approximation, some of the coordinates
become non-commutative. We find physical reasons to formal problems with
non-commutative gauge theories such as the issue with SU(N) gauge symmetries.
Our construction is applied to a minimal extension of the standard model. It is
shown that the Higgs sector might be non-commutative whereas the remaining
sectors of the standard model remain commutative. Signatures of this model at
the LHC are discussed. We then discuss an application to a dark matter sector
coupled to the Higgs sector of the standard model and show that here again,
dark matter could be non-commutative, the standard model fields remaining
commutative.
| [
{
"created": "Wed, 11 Apr 2007 07:11:01 GMT",
"version": "v1"
},
{
"created": "Sat, 15 Sep 2007 17:29:16 GMT",
"version": "v2"
}
] | 2008-04-23 | [
[
"Calmet",
"Xavier",
""
],
[
"Kober",
"Martin",
""
]
] | We consider gauge theories in a strong external magnetic like field. This situation can appear either in conventional four-dimensional theories, but also naturally in extra-dimensional theories and especially in brane world models. We show that in the lowest Landau level approximation, some of the coordinates become non-commutative. We find physical reasons to formal problems with non-commutative gauge theories such as the issue with SU(N) gauge symmetries. Our construction is applied to a minimal extension of the standard model. It is shown that the Higgs sector might be non-commutative whereas the remaining sectors of the standard model remain commutative. Signatures of this model at the LHC are discussed. We then discuss an application to a dark matter sector coupled to the Higgs sector of the standard model and show that here again, dark matter could be non-commutative, the standard model fields remaining commutative. |
hep-ph/9604261 | Sergey Goloskokov | S.V.Goloskokov | Diffractive Contribution to $g_1$ Structure Function at Small $x$ | 7 pages, latex, 3 Ps figures | null | null | null | hep-ph | null | We study the small $x$ diffractive contribution to the spin--dependent proton
structure function $g_1(x)$. We find that the $x\to 0$ behaviour of $ g_1(x)$
has a singular form like $1/(x^\alpha \ln^2(x))$ with $\alpha \sim 0.2-0.3$.
| [
{
"created": "Mon, 8 Apr 1996 05:46:10 GMT",
"version": "v1"
},
{
"created": "Wed, 10 Apr 1996 08:49:15 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Goloskokov",
"S. V.",
""
]
] | We study the small $x$ diffractive contribution to the spin--dependent proton structure function $g_1(x)$. We find that the $x\to 0$ behaviour of $ g_1(x)$ has a singular form like $1/(x^\alpha \ln^2(x))$ with $\alpha \sim 0.2-0.3$. |
0901.4711 | Vadim Guzey | K. Goeke (Ruhr U., Bochum), V. Guzey (Jefferson Lab), M. Siddikov
(Santa Maria U., Valparaiso & Ruhr U., Bochum & Uzbekistan Natl. U.) | Leading twist nuclear shadowing, nuclear generalized parton
distributions and nuclear DVCS at small x | 37 pages, 12 figures. Matches the published version, Phys. Rev. 79,
035210 (2009) | Phys.Rev.C79:035210,2009 | 10.1103/PhysRevC.79.035210 | USM-TH-243, JLAB-THY-09-941 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We generalize the leading twist theory of nuclear shadowing and calculate
quark and gluon generalized parton distributions (GPDs) of spinless nuclei. We
predict very large nuclear shadowing for nuclear GPDs. In the limit of the
purely transverse momentum transfer, our nuclear GPDs become
impact-parameter-dependent nuclear parton distributions (PDFs). Nuclear
shadowing induces nontrivial correlations between the impact parameter b and
the light-cone fraction x. We make predictions for the deeply virtual Compton
scattering (DVCS) amplitude and the DVCS cross section on Pb-208 at high
energies. We calculate the cross section of the Bethe-Heitler (BH) process and
address the issue of the extraction of the DVCS signal from the e A \to e
\gamma A cross section. We find that the e A \to e \gamma A differential cross
section is dominated by DVCS at the momentum transfer t near the minima of the
nuclear form factor. We also find that nuclear shadowing leads to dramatic
oscillations of the DVCS beam-spin asymmetry, A_{LU}, as a function of t. The
position of the points where A_{LU} changes sign is directly related to the
magnitude of nuclear shadowing.
| [
{
"created": "Thu, 29 Jan 2009 16:06:08 GMT",
"version": "v1"
},
{
"created": "Tue, 5 May 2009 20:08:50 GMT",
"version": "v2"
}
] | 2009-05-05 | [
[
"Goeke",
"K.",
"",
"Ruhr U., Bochum"
],
[
"Guzey",
"V.",
"",
"Jefferson Lab"
],
[
"Siddikov",
"M.",
"",
"Santa Maria U., Valparaiso & Ruhr U., Bochum & Uzbekistan Natl. U."
]
] | We generalize the leading twist theory of nuclear shadowing and calculate quark and gluon generalized parton distributions (GPDs) of spinless nuclei. We predict very large nuclear shadowing for nuclear GPDs. In the limit of the purely transverse momentum transfer, our nuclear GPDs become impact-parameter-dependent nuclear parton distributions (PDFs). Nuclear shadowing induces nontrivial correlations between the impact parameter b and the light-cone fraction x. We make predictions for the deeply virtual Compton scattering (DVCS) amplitude and the DVCS cross section on Pb-208 at high energies. We calculate the cross section of the Bethe-Heitler (BH) process and address the issue of the extraction of the DVCS signal from the e A \to e \gamma A cross section. We find that the e A \to e \gamma A differential cross section is dominated by DVCS at the momentum transfer t near the minima of the nuclear form factor. We also find that nuclear shadowing leads to dramatic oscillations of the DVCS beam-spin asymmetry, A_{LU}, as a function of t. The position of the points where A_{LU} changes sign is directly related to the magnitude of nuclear shadowing. |
1008.5151 | Matthew Buckley | Matthew R. Buckley and Michael J. Ramsey-Musolf | Diagnosing Spin at the LHC via Vector Boson Fusion | 5 pages, 4 figures | JHEP 1109:094,2011 | 10.1007/JHEP09(2011)094 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new technique for determining the spin of new massive particles
that might be discovered at the Large Hadron Collider. The method relies on
pair-production of the new particles in a kinematic regime where the vector
boson fusion production mechanism is enhanced. For this regime, we show that
the distribution of the leading jets as a function of their relative azimuthal
angle can be used to distinguish spin-0 from spin-1/2 particles. We illustrate
this effect by considering the particular cases of (i) strongly-interacting,
stable particles and (ii) supersymmetric particles carrying color charge. We
argue that this method should be applicable in a wide range of new physics
scenarios.
| [
{
"created": "Mon, 30 Aug 2010 20:00:04 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Oct 2010 18:06:56 GMT",
"version": "v2"
},
{
"created": "Wed, 23 Mar 2011 21:09:12 GMT",
"version": "v3"
}
] | 2011-09-23 | [
[
"Buckley",
"Matthew R.",
""
],
[
"Ramsey-Musolf",
"Michael J.",
""
]
] | We propose a new technique for determining the spin of new massive particles that might be discovered at the Large Hadron Collider. The method relies on pair-production of the new particles in a kinematic regime where the vector boson fusion production mechanism is enhanced. For this regime, we show that the distribution of the leading jets as a function of their relative azimuthal angle can be used to distinguish spin-0 from spin-1/2 particles. We illustrate this effect by considering the particular cases of (i) strongly-interacting, stable particles and (ii) supersymmetric particles carrying color charge. We argue that this method should be applicable in a wide range of new physics scenarios. |
1107.0696 | Peinado Eduardo | S. Morisi, Ketan M. Patel and E. Peinado | Model for T2K indication with maximal atmospheric angle and tri-maximal
solar angle | 7 pages, 2 figures, some references added and text improved | Phys.Rev.D84:053002,2011 | 10.1103/PhysRevD.84.053002 | IFIC/11-30 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently T2K gives hint in favor of large reactor angle. Most of the models,
with tri-bimaximal mixing at the leading order, can not reproduce such a large
mixing angle since they predict typically corrections for the reactor angle of
the order of the Cabibbo angle. In this letter, we discuss the possibility to
have large reactor angle within the T2K region with maximal atmospheric mixing
angle and trimaximal solar mixing angle, through the deviation from
tri-bimaximal. We derive the structure of neutrino mass matrix that leads to
the large reactor angle leaving maximal atmospheric angle and trimaximal solar
angle. It is shown that such a structure of neutrino mass matrix can arise in a
model with S4 flavor symmetry.
| [
{
"created": "Mon, 4 Jul 2011 18:23:13 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Jul 2011 17:20:52 GMT",
"version": "v2"
}
] | 2011-10-18 | [
[
"Morisi",
"S.",
""
],
[
"Patel",
"Ketan M.",
""
],
[
"Peinado",
"E.",
""
]
] | Recently T2K gives hint in favor of large reactor angle. Most of the models, with tri-bimaximal mixing at the leading order, can not reproduce such a large mixing angle since they predict typically corrections for the reactor angle of the order of the Cabibbo angle. In this letter, we discuss the possibility to have large reactor angle within the T2K region with maximal atmospheric mixing angle and trimaximal solar mixing angle, through the deviation from tri-bimaximal. We derive the structure of neutrino mass matrix that leads to the large reactor angle leaving maximal atmospheric angle and trimaximal solar angle. It is shown that such a structure of neutrino mass matrix can arise in a model with S4 flavor symmetry. |
1501.07696 | Wei-Tou Ni | Wei-Tou Ni | Searches for the role of spin and polarization in gravity: a five-year
update | 12 pages, 2 tables; Plenary talk presented in the 21st International
Symposium on Spin Physics (Spin2014), 19 October 2014 - 24 October 2014,
Peking University, Beijing, China; Based partly on arXiv:1411.0460,
arXiv:1410.0126 and arXiv:0912.5057 | null | 10.1142/S2010194516600107 | null | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Searches for the role of spin in gravitation dated before the firm
establishment of the electron spin in 1925. Since mass and spin, or helicity in
the case of zero mass, are the Casimir invariants of the Poincar\'e group and
mass participates in universal gravitation, these searches are natural steps to
pursue. In this update, we report on the progress on this topic in the last
five years after our last review. We begin with how is Lorentz/Poincar\'e group
in local physics arisen from spacetime structure as seen by photon and matter
through experiments/observations. The cosmic verification of the Galileo
Equivalence Principle for photons/electromagnetic wave packets (Universality of
Propagation in spacetime independent of photon energy and polarization, i.e.
nonbirefringence) constrains the spacetime constitutive tensor to high
precision to a core metric form with an axion degree and a dilaton degree of
freedom. Hughes-Drever-type experiments then constrain this core metric to
agree with the matter metric. Thus comes the metric with axion and dilation. In
local physics this metric gives the Lorentz/Poincar\'e covariance. Constraints
on axion and dilaton from polarized/unpolarized laboratory/astrophysical/cosmic
experiments/observations are presented. In the end, we review the theoretical
progress on the issue of gyrogravitational ratio for fundamental particles and
the experimental progress on the measurements of possible long
range/intermediate range spin-spin, spin-monopole and spin-cosmos interactions.
| [
{
"created": "Fri, 30 Jan 2015 08:36:21 GMT",
"version": "v1"
}
] | 2016-03-16 | [
[
"Ni",
"Wei-Tou",
""
]
] | Searches for the role of spin in gravitation dated before the firm establishment of the electron spin in 1925. Since mass and spin, or helicity in the case of zero mass, are the Casimir invariants of the Poincar\'e group and mass participates in universal gravitation, these searches are natural steps to pursue. In this update, we report on the progress on this topic in the last five years after our last review. We begin with how is Lorentz/Poincar\'e group in local physics arisen from spacetime structure as seen by photon and matter through experiments/observations. The cosmic verification of the Galileo Equivalence Principle for photons/electromagnetic wave packets (Universality of Propagation in spacetime independent of photon energy and polarization, i.e. nonbirefringence) constrains the spacetime constitutive tensor to high precision to a core metric form with an axion degree and a dilaton degree of freedom. Hughes-Drever-type experiments then constrain this core metric to agree with the matter metric. Thus comes the metric with axion and dilation. In local physics this metric gives the Lorentz/Poincar\'e covariance. Constraints on axion and dilaton from polarized/unpolarized laboratory/astrophysical/cosmic experiments/observations are presented. In the end, we review the theoretical progress on the issue of gyrogravitational ratio for fundamental particles and the experimental progress on the measurements of possible long range/intermediate range spin-spin, spin-monopole and spin-cosmos interactions. |
hep-ph/9608446 | Hai-Yang Cheng | Hai-Yang Cheng | Mesonic Form Factors in the Light-Front Quark Model | To appear in proceedings of the 1996 DPF Meeting of the American
Physical Society, Minneapolis, Minnesota, Aug 10-15, 1996, 4 pages | null | null | null | hep-ph | null | Form factors for $P\to P$ and $P\to V$ transitions due to the valence-quark
configuration are calculated directly in the physical time-like range of
momentum transfer within the light-front quark model. It is pointed out that
the Bauer-Stech-Wirbel type of light-front wave function fails to give a
correct normalization for the Isgur-Wise function at zero recoil in $P\to V$
transition. Some of the $P\to V$ form factors are found to depend on the
recoiling direction of the daughter mesons relative to their parents. Thus, the
inclusion of the non-valence contribution arising from quark-pair creation is
mandatory in order to ensure that the physical form factors are independent of
the recoiling direction.
| [
{
"created": "Mon, 26 Aug 1996 23:07:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Cheng",
"Hai-Yang",
""
]
] | Form factors for $P\to P$ and $P\to V$ transitions due to the valence-quark configuration are calculated directly in the physical time-like range of momentum transfer within the light-front quark model. It is pointed out that the Bauer-Stech-Wirbel type of light-front wave function fails to give a correct normalization for the Isgur-Wise function at zero recoil in $P\to V$ transition. Some of the $P\to V$ form factors are found to depend on the recoiling direction of the daughter mesons relative to their parents. Thus, the inclusion of the non-valence contribution arising from quark-pair creation is mandatory in order to ensure that the physical form factors are independent of the recoiling direction. |
hep-ph/0104201 | Masaaki Kuroda | Yoshimasa Kurihara, Masaaki Kuroda and Dieter Schildknecht | On e+e- --> W+W- --> 4f(+gamma) at LEP2 | 11 pages, latex | Phys.Lett. B509 (2001) 87-94 | 10.1016/S0370-2693(01)00531-7 | BI-TP 2001/05 | hep-ph | null | The results on e+e- --> W+W- --> 4f(+gamma) obtained by different groups are
compared with each other. Differences in the results for the total cross
section of up to about 0.6% are traced back to different ways of implementing
the double-pole approximation.
| [
{
"created": "Fri, 20 Apr 2001 05:13:00 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Kurihara",
"Yoshimasa",
""
],
[
"Kuroda",
"Masaaki",
""
],
[
"Schildknecht",
"Dieter",
""
]
] | The results on e+e- --> W+W- --> 4f(+gamma) obtained by different groups are compared with each other. Differences in the results for the total cross section of up to about 0.6% are traced back to different ways of implementing the double-pole approximation. |
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