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
hep-ph/0512098
Sergey Gevorkyan
S.R. Gevorkyan, A.V. Tarasov
Challenge of lepton pair production in peripheral collisions of relativistic ions
9 pages, 1 figure
Physics of Particles and Nuclei Letters 10: 167-174, 2013
null
null
hep-ph
null
The new approach to the lepton pair production in the Coulomb field of two highly relativistic nuclei was developed.Solving the operator equation for lepton scattering in arbitrary Coulomb field, we obtain the amplitudes for lepton scattering in the Coulomb potential in terms of light cone variables. Using the Watson expansion for the amplitude of lepton scattering on two centers we propose prescription which allows one to construct the amplitude for lepton pair production in the Coulomb field of two highly relativistic ions. We show that for the certain sums of finite terms of the Watson series numerous cancellations lead to infrared stability of amplitude.
[ { "created": "Thu, 8 Dec 2005 10:48:35 GMT", "version": "v1" } ]
2013-07-23
[ [ "Gevorkyan", "S. R.", "" ], [ "Tarasov", "A. V.", "" ] ]
The new approach to the lepton pair production in the Coulomb field of two highly relativistic nuclei was developed.Solving the operator equation for lepton scattering in arbitrary Coulomb field, we obtain the amplitudes for lepton scattering in the Coulomb potential in terms of light cone variables. Using the Watson expansion for the amplitude of lepton scattering on two centers we propose prescription which allows one to construct the amplitude for lepton pair production in the Coulomb field of two highly relativistic ions. We show that for the certain sums of finite terms of the Watson series numerous cancellations lead to infrared stability of amplitude.
1312.0592
Zvi Bern
Z. Bern, L. J. Dixon, F. Febres Cordero, S. Hoeche, H. Ita, D. A. Kosower, N. A. Lo Presti and D. Maitre
Next-to-leading order diphoton+2-jet production at the LHC
10 pages, 4 figures, Presented at 11th International Symposium on Radiative Corrections (RADCOR 2013), 22-27 September 2013, Lumley Castle Hotel, Durham, UK
null
null
IPhT--T13/269, SLAC--PUB--15847, UCLA/13/TEP/110, IPPP/13/96
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present results from a recent calculation of prompt photon-pair production in association with two jets to next-to-leading order (NLO) at the LHC. The virtual contribution is evaluated using the BlackHat library, a numerical implementation of on-shell methods for one-loop amplitudes, in conjunction with SHERPA. We study four sets of cuts: standard jet cuts, a set of Higgs-related cuts suggested by ATLAS, and corresponding sets which isolate the kinematic region where the process becomes the largest background to Higgs production via vector-boson fusion.
[ { "created": "Mon, 2 Dec 2013 20:59:09 GMT", "version": "v1" } ]
2013-12-03
[ [ "Bern", "Z.", "" ], [ "Dixon", "L. J.", "" ], [ "Cordero", "F. Febres", "" ], [ "Hoeche", "S.", "" ], [ "Ita", "H.", "" ], [ "Kosower", "D. A.", "" ], [ "Presti", "N. A. Lo", "" ], [ "Maitre", "D.", "" ] ]
We present results from a recent calculation of prompt photon-pair production in association with two jets to next-to-leading order (NLO) at the LHC. The virtual contribution is evaluated using the BlackHat library, a numerical implementation of on-shell methods for one-loop amplitudes, in conjunction with SHERPA. We study four sets of cuts: standard jet cuts, a set of Higgs-related cuts suggested by ATLAS, and corresponding sets which isolate the kinematic region where the process becomes the largest background to Higgs production via vector-boson fusion.
2108.02779
Andrew Larkoski
Kees Benkendorfer and Andrew J. Larkoski
Grooming at the Cusp: All-Orders Predictions for the Transition Region of Jet Groomers
20 pages + appendices, 6 figures; v2: added an appendix with plots of the cusp for 1 TeV collisions; v3: JHEP version, added some more discussion of the accuracy and validity of the factorization
null
10.1007/JHEP11(2021)188
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Jet grooming has emerged as a necessary and vital tool for mitigating contamination radiation in jets. The additional restrictions on emissions imposed by the groomer can result in non-smooth behavior of resulting fixed-order distributions of observables measured on groomed jets. As a concrete example, we study the cusp in the hemisphere mass distribution of $e^+e^-\to$ hadrons events groomed with soft drop. We identify the leading emissions that contribute in the region about the cusp and formulate an all-orders factorization theorem that describes how the cusp is resolved through arbitrary strongly-ordered soft and collinear emissions. The factorization theorem exhibits numerous novel features such as contributions from collinear modes that can cross hemisphere boundaries as well as requiring explicit subtraction of the limit in which resolved emissions become collinear to the hard core. We present resummation of the cusp region through next-to-leading logarithmic accuracy and describe how it can be matched with established factorization theorems that describe other groomed phase space regions.
[ { "created": "Thu, 5 Aug 2021 18:00:00 GMT", "version": "v1" }, { "created": "Thu, 19 Aug 2021 17:44:30 GMT", "version": "v2" }, { "created": "Wed, 27 Oct 2021 12:50:10 GMT", "version": "v3" } ]
2021-12-08
[ [ "Benkendorfer", "Kees", "" ], [ "Larkoski", "Andrew J.", "" ] ]
Jet grooming has emerged as a necessary and vital tool for mitigating contamination radiation in jets. The additional restrictions on emissions imposed by the groomer can result in non-smooth behavior of resulting fixed-order distributions of observables measured on groomed jets. As a concrete example, we study the cusp in the hemisphere mass distribution of $e^+e^-\to$ hadrons events groomed with soft drop. We identify the leading emissions that contribute in the region about the cusp and formulate an all-orders factorization theorem that describes how the cusp is resolved through arbitrary strongly-ordered soft and collinear emissions. The factorization theorem exhibits numerous novel features such as contributions from collinear modes that can cross hemisphere boundaries as well as requiring explicit subtraction of the limit in which resolved emissions become collinear to the hard core. We present resummation of the cusp region through next-to-leading logarithmic accuracy and describe how it can be matched with established factorization theorems that describe other groomed phase space regions.
1501.03781
Alberto Salvio
Alberto Salvio
A Simple Motivated Completion of the Standard Model below the Planck Scale: Axions and Right-Handed Neutrinos
8 pages, 4 figures. Phys. Lett. B version: references and discussion on light right-handed neutrinos added
null
10.1016/j.physletb.2015.03.015
IFT-UAM/CSIC-15-003
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study a simple Standard Model (SM) extension, which includes three families of right-handed neutrinos with generic non-trivial flavor structure and an economic implementation of the invisible axion idea. We find that in some regions of the parameter space this model accounts for all experimentally confirmed pieces of evidence for physics beyond the SM: it explains neutrino masses (via the type-I see-saw mechanism), dark matter, baryon asymmetry (through leptogenesis), solve the strong CP problem and has a stable electroweak vacuum. The last property may allow us to identify the Higgs field with the inflaton.
[ { "created": "Thu, 15 Jan 2015 19:16:39 GMT", "version": "v1" }, { "created": "Mon, 26 Jan 2015 11:57:42 GMT", "version": "v2" }, { "created": "Wed, 11 Mar 2015 10:19:47 GMT", "version": "v3" } ]
2015-04-14
[ [ "Salvio", "Alberto", "" ] ]
We study a simple Standard Model (SM) extension, which includes three families of right-handed neutrinos with generic non-trivial flavor structure and an economic implementation of the invisible axion idea. We find that in some regions of the parameter space this model accounts for all experimentally confirmed pieces of evidence for physics beyond the SM: it explains neutrino masses (via the type-I see-saw mechanism), dark matter, baryon asymmetry (through leptogenesis), solve the strong CP problem and has a stable electroweak vacuum. The last property may allow us to identify the Higgs field with the inflaton.
hep-ph/9509370
Michael Martin Nieto
Michael Martin Nieto
Quantum Interference: From Kaons to Neutrinos (with Quantum Beats in between)
12 pages, LaTeX, 3 figures
Hyperfine Interact. 100 (1996) 193
10.1007/BF02059943
LA-UR-95-2030
hep-ph quant-ph
null
Using the vehicle of resolving an apparent paradox, a discussion of quantum interference is presented. The understanding of a number of different physical phenomena can be unified, in this context. These range from the neutral kaon system to massive neutrinos, not to mention quantum beats, Rydberg wave packets, and neutron gravity.
[ { "created": "Fri, 22 Sep 1995 21:42:55 GMT", "version": "v1" } ]
2009-10-28
[ [ "Nieto", "Michael Martin", "" ] ]
Using the vehicle of resolving an apparent paradox, a discussion of quantum interference is presented. The understanding of a number of different physical phenomena can be unified, in this context. These range from the neutral kaon system to massive neutrinos, not to mention quantum beats, Rydberg wave packets, and neutron gravity.
2005.07222
Navin McGinnis
Radovan Dermisek, Enrico Lunghi, Navin McGinnis, Seodong Shin
Signals with six bottom quarks for charged and neutral Higgs bosons
21 pages, 12 figures, 4 tables. v2: Minor mistakes and typos corrected, main results unchanged, matches published version
null
10.1007/JHEP07(2020)241
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In extensions of two Higgs doublet models with vectorlike quarks, the decays of vectorlike quarks may easily be dominated by cascade decays through charged or neutral Higgs bosons leading to signatures with 6 top or bottom quarks. Since top quark decays also contain bottom quarks, a common signature for many possible decay chains is 6 bottom quarks in the final state. We present a search strategy focusing on this final state and find the mass ranges of vectorlike quarks and Higgs bosons that can be explored at the Large Hadron Collider. Among other results, the sensitivity to the charged and neutral Higgs bosons, extending to about 2 TeV, stands out when compared to models without vectorlike matter.
[ { "created": "Thu, 14 May 2020 18:52:18 GMT", "version": "v1" }, { "created": "Sun, 2 Aug 2020 22:52:13 GMT", "version": "v2" } ]
2020-08-26
[ [ "Dermisek", "Radovan", "" ], [ "Lunghi", "Enrico", "" ], [ "McGinnis", "Navin", "" ], [ "Shin", "Seodong", "" ] ]
In extensions of two Higgs doublet models with vectorlike quarks, the decays of vectorlike quarks may easily be dominated by cascade decays through charged or neutral Higgs bosons leading to signatures with 6 top or bottom quarks. Since top quark decays also contain bottom quarks, a common signature for many possible decay chains is 6 bottom quarks in the final state. We present a search strategy focusing on this final state and find the mass ranges of vectorlike quarks and Higgs bosons that can be explored at the Large Hadron Collider. Among other results, the sensitivity to the charged and neutral Higgs bosons, extending to about 2 TeV, stands out when compared to models without vectorlike matter.
0710.1454
Yue Zhang
Yue Zhang (Peking U. & Maryland U.), Haipeng An (Maryland U.), Xiangdong Ji (Maryland U. & Peking U.)
Constraining Right-Handed Scale Through Kaon Mixing in SUSY Left-Right Model
12 pages, new figures added
Phys.Rev.D78:035006,2008
10.1103/PhysRevD.78.035006
null
hep-ph
null
We study flavor-changing neutral current and CP violations in the minimal supersymmetric left-right model. We calculate the beyond-standard-model contributions to the neutral kaon mixing $\Delta M_K$ and $\epsilon$, and find possible to have a numerical cancelation between the contributions from the right-handed gauge boson and supersymmetric box diagram. With the cancelation, the right-handed $W$-boson mass scale can be lowered to about 2 TeV, well within the search limit of LHC.
[ { "created": "Mon, 8 Oct 2007 01:45:16 GMT", "version": "v1" }, { "created": "Fri, 23 May 2008 02:07:49 GMT", "version": "v2" } ]
2008-11-26
[ [ "Zhang", "Yue", "", "Peking U. & Maryland U." ], [ "An", "Haipeng", "", "Maryland U." ], [ "Ji", "Xiangdong", "", "Maryland U. & Peking U." ] ]
We study flavor-changing neutral current and CP violations in the minimal supersymmetric left-right model. We calculate the beyond-standard-model contributions to the neutral kaon mixing $\Delta M_K$ and $\epsilon$, and find possible to have a numerical cancelation between the contributions from the right-handed gauge boson and supersymmetric box diagram. With the cancelation, the right-handed $W$-boson mass scale can be lowered to about 2 TeV, well within the search limit of LHC.
hep-ph/0406120
Mairi Sakellariadou
Jonathan Rocher and Mairi Sakellariadou
Constraints on Supersymmetric Grand Unified Theories from Cosmology
32 pages, 7 figures. To match published version
JCAP0503:004,2005
10.1088/1475-7516/2005/03/004
null
hep-ph astro-ph gr-qc hep-th
null
Within the context of SUSY GUTs, cosmic strings are generically formed at the end of hybrid inflation. However, the WMAP CMB measurements strongly constrain the possible cosmic strings contribution to the angular power spectrum of anisotropies. We investigate the parameter space of SUSY hybrid (F- and D- term) inflation, to get the conditions under which theoretical predictions are in agreement with data. The predictions of F-term inflation are in agreement with data, only if the superpotential coupling $\kappa$ is small. In particular, for SUSY SO(10), the upper bound is $\kappa\lsim 7\times 10^{-7}$. This fine tuning problem can be lifted if we employ the curvaton mechanism, in which case $\kappa\lsim 8\times 10^{-3}$; higher values are not allowed by the gravitino constraint. The constraint on $\kappa$ is equivalent to a constraint on the SSB mass scale $M$, namely $M \lsim 2\times 10^{15}$ GeV. The study of D-term inflation shows that the inflaton field is of the order of the Planck scale; one should therefore consider SUGRA. We find that the cosmic strings contribution to the CMB anisotropies is not constant, but it is strongly dependent on the gauge coupling $g$ and on the superpotential coupling $\lambda$. We obtain $g\lsim 2\times 10^{-2}$ and $\lambda \lsim 3\times 10^{-5}$. SUGRA corrections induce also a lower limit for $\lambda$. Equivalently, the Fayet-Iliopoulos term $\xi$ must satisfy $\sqrt\xi \lsim 2\times 10^{15}$ GeV. This constraint holds for all allowed values of $g$.
[ { "created": "Thu, 10 Jun 2004 11:18:56 GMT", "version": "v1" }, { "created": "Thu, 24 Mar 2005 15:03:17 GMT", "version": "v2" } ]
2008-11-26
[ [ "Rocher", "Jonathan", "" ], [ "Sakellariadou", "Mairi", "" ] ]
Within the context of SUSY GUTs, cosmic strings are generically formed at the end of hybrid inflation. However, the WMAP CMB measurements strongly constrain the possible cosmic strings contribution to the angular power spectrum of anisotropies. We investigate the parameter space of SUSY hybrid (F- and D- term) inflation, to get the conditions under which theoretical predictions are in agreement with data. The predictions of F-term inflation are in agreement with data, only if the superpotential coupling $\kappa$ is small. In particular, for SUSY SO(10), the upper bound is $\kappa\lsim 7\times 10^{-7}$. This fine tuning problem can be lifted if we employ the curvaton mechanism, in which case $\kappa\lsim 8\times 10^{-3}$; higher values are not allowed by the gravitino constraint. The constraint on $\kappa$ is equivalent to a constraint on the SSB mass scale $M$, namely $M \lsim 2\times 10^{15}$ GeV. The study of D-term inflation shows that the inflaton field is of the order of the Planck scale; one should therefore consider SUGRA. We find that the cosmic strings contribution to the CMB anisotropies is not constant, but it is strongly dependent on the gauge coupling $g$ and on the superpotential coupling $\lambda$. We obtain $g\lsim 2\times 10^{-2}$ and $\lambda \lsim 3\times 10^{-5}$. SUGRA corrections induce also a lower limit for $\lambda$. Equivalently, the Fayet-Iliopoulos term $\xi$ must satisfy $\sqrt\xi \lsim 2\times 10^{15}$ GeV. This constraint holds for all allowed values of $g$.
hep-ph/0604209
Jean-Paul Blaizot
G. Baym, J.-P. Blaizot, F. Gelis, T. Matsui
Landau-Pomeranchuck-Migdal effect in a quark-gluon plasma and the Boltzmann equation
17 pages, 4 figures Minor rewriting. In particular, the specific small angle behavior of the collision term involved in the LPM effect is better explained. Version accepted for publication in Physics Letters B
Phys.Lett.B644:48-53,2007
10.1016/j.physletb.2006.11.011
ECT*-05_21, SPhT-T06-010, UT-Komaba/06-3
hep-ph cond-mat.other nucl-th
null
We show how the Landau-Pomeranchuk-Migdal effect on photon production rates in a quark-gluon plasma can be derived via the usual Boltzmann equation. To do this, we first derive the electromagnetic polarization tensor using linear response theory, and then formulate the Boltzmann equation including the collisions mediated by soft gluon exchanges. We then identify the resulting expression for the production rate with that obtained by the field-theoretic formalism recently proposed by Arnold, Moore and Yaffe. To illustrate the LPM effect we solve the Boltzmann equation in the diffusion approximation.
[ { "created": "Tue, 25 Apr 2006 07:09:18 GMT", "version": "v1" }, { "created": "Sat, 2 Dec 2006 18:52:22 GMT", "version": "v2" } ]
2011-07-19
[ [ "Baym", "G.", "" ], [ "Blaizot", "J. -P.", "" ], [ "Gelis", "F.", "" ], [ "Matsui", "T.", "" ] ]
We show how the Landau-Pomeranchuk-Migdal effect on photon production rates in a quark-gluon plasma can be derived via the usual Boltzmann equation. To do this, we first derive the electromagnetic polarization tensor using linear response theory, and then formulate the Boltzmann equation including the collisions mediated by soft gluon exchanges. We then identify the resulting expression for the production rate with that obtained by the field-theoretic formalism recently proposed by Arnold, Moore and Yaffe. To illustrate the LPM effect we solve the Boltzmann equation in the diffusion approximation.
hep-ph/0401204
Akaki Rusetsky
J. Gasser (Bern University), A. Rusetsky (Bonn University and Tbilisi University), J. Schacher (Bern University)
HadAtom03
46 pages, 16 postscript figures, Proceedings of the workshop "HadAtom03," 13-17 October Trento, Italy
null
null
Preprints ECT*-04-01, HISKP-TH-04/02
hep-ph
null
These are the proceedings of the workshop "HadAtom03," held at the European Centre for Theoretical Nuclear Physics and Related Studies (ECT*), Trento (Italy), October 13 - 17, 2003. The main topics discussed at the workshop were the physics of hadronic atoms and in this context recent results in experiment and theory. Included here are the list of participants, the scientific program and a short contribution from each speaker.
[ { "created": "Mon, 26 Jan 2004 15:25:59 GMT", "version": "v1" } ]
2007-05-23
[ [ "Gasser", "J.", "", "Bern University" ], [ "Rusetsky", "A.", "", "Bonn University and Tbilisi\n University" ], [ "Schacher", "J.", "", "Bern University" ] ]
These are the proceedings of the workshop "HadAtom03," held at the European Centre for Theoretical Nuclear Physics and Related Studies (ECT*), Trento (Italy), October 13 - 17, 2003. The main topics discussed at the workshop were the physics of hadronic atoms and in this context recent results in experiment and theory. Included here are the list of participants, the scientific program and a short contribution from each speaker.
1407.8448
Rick Gupta
Rick S. Gupta
BSM Primary Effects: The complete set of predictions from the dimension-6 BSM Lagrangian
Based on talk given at DIS 2014. This talk was completely based on arXiv:1405.0181, which was written in collaboration with A. Pomarol and F. Riva
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a physical parameterization of the leading effects beyond the SM (BSM), that give us, at present, the best way to constrain heavy new-physics at low-energies. We call these effects that constrain all possible interactions at the dimension 6 level, BSM Primary effects; there are 8 primaries related to Higgs physics, 3 related to Triple Gauge Couplings and 7 related to Z- pole measurements at LEP. Starting from these experimentally measurable deformations (and not operators), we construct the dimension 6 Lagrangian in a bottom up way. We, thus, show that other BSM effects are not independent from the primary ones and we provide the explicit correlations. We also discuss the theoretical expectation for the size of these BSM primaries in some well-motivated BSM theories.
[ { "created": "Thu, 31 Jul 2014 15:05:43 GMT", "version": "v1" } ]
2014-08-01
[ [ "Gupta", "Rick S.", "" ] ]
We present a physical parameterization of the leading effects beyond the SM (BSM), that give us, at present, the best way to constrain heavy new-physics at low-energies. We call these effects that constrain all possible interactions at the dimension 6 level, BSM Primary effects; there are 8 primaries related to Higgs physics, 3 related to Triple Gauge Couplings and 7 related to Z- pole measurements at LEP. Starting from these experimentally measurable deformations (and not operators), we construct the dimension 6 Lagrangian in a bottom up way. We, thus, show that other BSM effects are not independent from the primary ones and we provide the explicit correlations. We also discuss the theoretical expectation for the size of these BSM primaries in some well-motivated BSM theories.
hep-ph/9707337
Hoang
A.H. Hoang (University of California, San Diego), P. Labelle, S.M. Zebarjad (McGill University, Montreal)
The Single Photon Annihilation Contributions to the Positronium Hyperfine Splitting to Order $m_e\alpha^6$
8 pages, latex, two eps figures included
Phys.Rev.Lett. 79 (1997) 3387-3390
10.1103/PhysRevLett.79.3387
McGill/97-15, UCSD/PTH 97-15
hep-ph physics.atom-ph
null
The single photon annihilation contributions for the positronium ground state hyperfine splitting are calculated analytically to order $m_e\alpha^6$ using NRQED. Based on intuitive physical arguments the same result can also be determined by a trivial calculation using results from existing literature. Our result completes the hyperfine splitting calculation to order $m_e\alpha^6$. We compare the theoretical prediction with the most recent experimental measurement.
[ { "created": "Sun, 13 Jul 1997 23:44:54 GMT", "version": "v1" } ]
2009-10-30
[ [ "Hoang", "A. H.", "", "University of California, San Diego" ], [ "Labelle", "P.", "", "McGill University, Montreal" ], [ "Zebarjad", "S. M.", "", "McGill University, Montreal" ] ]
The single photon annihilation contributions for the positronium ground state hyperfine splitting are calculated analytically to order $m_e\alpha^6$ using NRQED. Based on intuitive physical arguments the same result can also be determined by a trivial calculation using results from existing literature. Our result completes the hyperfine splitting calculation to order $m_e\alpha^6$. We compare the theoretical prediction with the most recent experimental measurement.
2406.20067
Diego Lopez Gutierrez
Innes Bigaran, P. S. Bhupal Dev, Diego Lopez Gutierrez, Pedro A. N. Machado
Tau Tridents at Accelerator Neutrino Facilities
14 pages, 12 figures, 1 table
null
null
FERMILAB-PUB-24-0318-T
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We present the first detailed study of Standard Model (SM) neutrino tridents involving tau leptons at the near detectors of accelerator neutrino facilities. These processes were previously thought to be negligible, even at future facilities like DUNE, based on approximations that underestimated the tau trident cross sections. Our full $2\to 4$ calculation, including both coherent and incoherent scatterings, reveals that the DUNE near detector will actually get a non-negligible number of tau tridents, which is an important background to new physics searches. We identify promising kinematic features that may allow distinction of tau tridents from the usual neutrino charged-current background at DUNE, and thus could establish the observation of tau tridents for the first time. We also comment on the detection prospects at other accelerator and collider neutrino experiments.
[ { "created": "Fri, 28 Jun 2024 17:23:44 GMT", "version": "v1" } ]
2024-07-01
[ [ "Bigaran", "Innes", "" ], [ "Dev", "P. S. Bhupal", "" ], [ "Gutierrez", "Diego Lopez", "" ], [ "Machado", "Pedro A. N.", "" ] ]
We present the first detailed study of Standard Model (SM) neutrino tridents involving tau leptons at the near detectors of accelerator neutrino facilities. These processes were previously thought to be negligible, even at future facilities like DUNE, based on approximations that underestimated the tau trident cross sections. Our full $2\to 4$ calculation, including both coherent and incoherent scatterings, reveals that the DUNE near detector will actually get a non-negligible number of tau tridents, which is an important background to new physics searches. We identify promising kinematic features that may allow distinction of tau tridents from the usual neutrino charged-current background at DUNE, and thus could establish the observation of tau tridents for the first time. We also comment on the detection prospects at other accelerator and collider neutrino experiments.
hep-ph/9612442
null
P. Binetruy, N. Irges, S. Lavignac and P. Ramond
Anomalous U(1) and low-energy physics: the power of D-flatness and holomorphy
16 pages, latex, no figures
Phys.Lett.B403:38-46,1997
10.1016/S0370-2693(97)00408-5
LBNL-39745, UCB-PTH-96/62, UFIFT-HEP-96-32, LPTHE-ORSAY 96/101
hep-ph
null
In models with an anomalous abelian symmetry broken at a very large scale, we study which requirements to impose on the anomalous charges in order to prevent standard model fields from acquiring large vacuum expectation values. The use of holomorphic invariants to study D-flat directions for the anomalous symmetry, proves to be a very powerful tool. We find that in order to forbid unphysical vacuum configurations at that scale, the superpotential must contain many interaction terms, including the usual Yukawa terms. Our analysis suggests that the anomalous charge of the \mu-term is zero. It is remarkable that, together with the seesaw mechanism, and mass hierarchies, this implies a natural conservation of R-parity.
[ { "created": "Sat, 21 Dec 1996 03:05:37 GMT", "version": "v1" } ]
2014-11-17
[ [ "Binetruy", "P.", "" ], [ "Irges", "N.", "" ], [ "Lavignac", "S.", "" ], [ "Ramond", "P.", "" ] ]
In models with an anomalous abelian symmetry broken at a very large scale, we study which requirements to impose on the anomalous charges in order to prevent standard model fields from acquiring large vacuum expectation values. The use of holomorphic invariants to study D-flat directions for the anomalous symmetry, proves to be a very powerful tool. We find that in order to forbid unphysical vacuum configurations at that scale, the superpotential must contain many interaction terms, including the usual Yukawa terms. Our analysis suggests that the anomalous charge of the \mu-term is zero. It is remarkable that, together with the seesaw mechanism, and mass hierarchies, this implies a natural conservation of R-parity.
1310.8419
Wojciech Broniowski
Wojciech Broniowski, Enrique Ruiz Arriola
Valence double parton distributions of the nucleon in a simple model
6 pages, talk presented at Light Cone 2013, Skiathos, Greece, 20-24 May 3013
null
10.1007/s00601-014-0840-4
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Valence double parton distribution functions of the nucleon are evaluated in the framework of a simple model, where the conservation of the longitudinal momentum is taken into account. The leading-order DGLAP QCD evolution from the low quark-model scale to higher renormalization scales is carried out via the Mellin moments of the distributions. Results of the valence quark correlation function show that in general the double distributions cannot be approximated as a product of the single-particle distributions.
[ { "created": "Thu, 31 Oct 2013 08:04:16 GMT", "version": "v1" } ]
2015-06-17
[ [ "Broniowski", "Wojciech", "" ], [ "Arriola", "Enrique Ruiz", "" ] ]
Valence double parton distribution functions of the nucleon are evaluated in the framework of a simple model, where the conservation of the longitudinal momentum is taken into account. The leading-order DGLAP QCD evolution from the low quark-model scale to higher renormalization scales is carried out via the Mellin moments of the distributions. Results of the valence quark correlation function show that in general the double distributions cannot be approximated as a product of the single-particle distributions.
1608.04186
Dian-Yong Chen
Jun-Zhang Wang, Dian-Yong Chen, Qin-Tao Song, Xiang Liu, Takayuki Matsuki
Revealing the inner structure of the newly observed $D_2^*(3000)$
7 pages, 4 figures, 3 tables, minor revision, accepted by Phys. Rev. D
Phys. Rev. D 94, 094044 (2016)
10.1103/PhysRevD.94.094044
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Stimulated by the recent observation of the $D_2^\ast(3000)$, we study the decay behaviors of the $3P$ and $2F$ charmed mesons in the present work. By comparing the masses and decay properties of the $3^3P_2$ and $2^3F_2$ charmed mesons with the observation of the $D_2^\ast(3000)$, we conclude that the most possible assignment of the $D_2^\ast(3000)$ is the $3^3P_2$ charmed meson, while the assignment of the $2^3F_2$ charmed meson could not be fully exclude. The results of the unobserved $3P$ and $2F$ charmed mesons in this work could provide some fundamental information of searching for these charmed mesons in the further experiments by LHCb and forthcoming Belle II.
[ { "created": "Mon, 15 Aug 2016 06:18:34 GMT", "version": "v1" }, { "created": "Tue, 23 Aug 2016 14:35:57 GMT", "version": "v2" }, { "created": "Tue, 1 Nov 2016 02:47:03 GMT", "version": "v3" }, { "created": "Thu, 3 Nov 2016 01:56:18 GMT", "version": "v4" }, { "created": "Tue, 29 Nov 2016 02:24:55 GMT", "version": "v5" } ]
2016-12-07
[ [ "Wang", "Jun-Zhang", "" ], [ "Chen", "Dian-Yong", "" ], [ "Song", "Qin-Tao", "" ], [ "Liu", "Xiang", "" ], [ "Matsuki", "Takayuki", "" ] ]
Stimulated by the recent observation of the $D_2^\ast(3000)$, we study the decay behaviors of the $3P$ and $2F$ charmed mesons in the present work. By comparing the masses and decay properties of the $3^3P_2$ and $2^3F_2$ charmed mesons with the observation of the $D_2^\ast(3000)$, we conclude that the most possible assignment of the $D_2^\ast(3000)$ is the $3^3P_2$ charmed meson, while the assignment of the $2^3F_2$ charmed meson could not be fully exclude. The results of the unobserved $3P$ and $2F$ charmed mesons in this work could provide some fundamental information of searching for these charmed mesons in the further experiments by LHCb and forthcoming Belle II.
0911.2642
Egle Tomasi-Gustafsson
Egle Tomasi-Gustafsson
Charge asymmetry and symmetry properties
Contribution to XIII Workshop On High Energy Spin Physics (DSPIN), Dubna, Russia September 1 - 5, 2009 8 pages 3 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Applying general symmetry properties of electromagnetic interaction, information from electron proton elastic scattering data can be related to charge asymmetry in the annihilation channels $e^++e^-\leftrightarrow \bar p + p$ and to the ratio of the cross section of elastic electron and positron scattering on the proton. A compared analysis of the existing data allows to draw conclusions on the reaction mechanism.
[ { "created": "Fri, 13 Nov 2009 16:03:55 GMT", "version": "v1" } ]
2009-11-16
[ [ "Tomasi-Gustafsson", "Egle", "" ] ]
Applying general symmetry properties of electromagnetic interaction, information from electron proton elastic scattering data can be related to charge asymmetry in the annihilation channels $e^++e^-\leftrightarrow \bar p + p$ and to the ratio of the cross section of elastic electron and positron scattering on the proton. A compared analysis of the existing data allows to draw conclusions on the reaction mechanism.
hep-ph/0609205
Agnes Mocsy
Agnes Mocsy, Peter Petreczky, Jorge Casalderrey-Solana
Ground State Quarkonium Spectral Functions Above Deconfinement
Contribution to proceedings of "Strong and Electroweak Matter 2006", Brookhaven, NY, May 2006 and "Hard Probes 2006" Asilomar, CA, June 2006
Nucl.Phys.A783:485-488,2007; Nucl.Phys.A785:266-269,2007
10.1016/j.nuclphysa.2006.11.100 10.1016/j.nuclphysa.2006.11.147
null
hep-ph
null
We discuss the temperature-dependence of S-wave quarkonium spectral functions in a nonrelativistic Green's function approach and compare these to lattice QCD results.
[ { "created": "Wed, 20 Sep 2006 19:15:46 GMT", "version": "v1" } ]
2008-11-26
[ [ "Mocsy", "Agnes", "" ], [ "Petreczky", "Peter", "" ], [ "Casalderrey-Solana", "Jorge", "" ] ]
We discuss the temperature-dependence of S-wave quarkonium spectral functions in a nonrelativistic Green's function approach and compare these to lattice QCD results.
hep-ph/9701408
null
Michael C. Birse, Thomas D. Cohen and Judith A. McGovern
Relations Among Correlation Functions in the High Temperature Phase of QCD with Broken SU(3)
8 pages
Phys.Lett. B399 (1997) 263-266
10.1016/S0370-2693(97)00279-7
U. of MD PP\#97-076
hep-ph
null
Group-theoretic arguments are used to determine the dependence of two-point correlators of quark bilinears on the current quark masses. The leading difference between $\pi$ and $\delta$ correlators is found to be of order $m_s$ times a U(1)$_{\scriptscriptstyle A}$-violating correlator. These general arguments are consistent with Schaefer's observation that if U(1)$_{\scriptscriptstyle A}$ violation persists to high enough temperatures then the strange $\eta$ can be lighter than the non-strange one.
[ { "created": "Wed, 29 Jan 1997 14:52:19 GMT", "version": "v1" } ]
2009-10-30
[ [ "Birse", "Michael C.", "" ], [ "Cohen", "Thomas D.", "" ], [ "McGovern", "Judith A.", "" ] ]
Group-theoretic arguments are used to determine the dependence of two-point correlators of quark bilinears on the current quark masses. The leading difference between $\pi$ and $\delta$ correlators is found to be of order $m_s$ times a U(1)$_{\scriptscriptstyle A}$-violating correlator. These general arguments are consistent with Schaefer's observation that if U(1)$_{\scriptscriptstyle A}$ violation persists to high enough temperatures then the strange $\eta$ can be lighter than the non-strange one.
hep-ph/9607331
null
Keiichi Akama (Saitama Medical College) and Takashi Hattori (Kanagawa Dental College)
Compositeness Condition for Dynamically Induced Gauge Theories
7 pages, revtex, 3 Postscript figures
Phys.Lett.B392:383-388,1997
10.1016/S0370-2693(96)01580-8
null
hep-ph
null
We show that the compositeness condition for the induced gauge boson in the four-fermion interaction theory actually works beyond the one-loop approximation. The next-to-leading contributions are calculated, and turn out to be reasonably suppressed, so that the leading-order approximation is justified.
[ { "created": "Tue, 16 Jul 1996 06:12:54 GMT", "version": "v1" }, { "created": "Tue, 13 Aug 1996 04:27:42 GMT", "version": "v2" } ]
2014-11-17
[ [ "Akama", "Keiichi", "", "Saitama Medical College" ], [ "Hattori", "Takashi", "", "Kanagawa\n Dental College" ] ]
We show that the compositeness condition for the induced gauge boson in the four-fermion interaction theory actually works beyond the one-loop approximation. The next-to-leading contributions are calculated, and turn out to be reasonably suppressed, so that the leading-order approximation is justified.
2005.07762
Pier Francesco Monni
K. Becker, F. Caola, A. Massironi, B. Mistlberger, P. F. Monni, X. Chen, S. Frixione, T. Gehrmann, N. Glover, K. Hamilton, A. Huss, S. P. Jones, A. Karlberg, M. Kerner, K. Kudashkin, J. M. Lindert, G. Luisoni, M. L. Mangano, S. Pozzorini, E. Re, G. P. Salam, E. Vryonidou, C. Wever
Precise predictions for boosted Higgs production
Journal version
SciPost Phys.Core 7 (2024) 001
10.21468/SciPostPhysCore.7.1.001
CERN-TH-2020-074
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inclusive Higgs boson production at large transverse momentum is induced by different production channels. We focus on the leading production through gluon fusion, and perform a consistent combination of the state of the art calculations obtained in the infinite-top-mass effective theory at next-to-next-to-leading order (NNLO) and in the full Standard Model (SM) at next-to-leading order (NLO). We thus present approximate QCD predictions for this process at NNLO, and a study of the corresponding perturbative uncertainties. This calculation is then compared with those obtained with commonly used event generators, and we observe that the description of the considered kinematic regime provided by these tools is in good agreement with state of the art calculations. Finally, we present accurate predictions for other production channels such as vector boson fusion, and associated production with a gauge boson, and with a $t\bar{t}$ pair. We find that, at large transverse momentum, the contribution of other production modes is substantial, and therefore must be included for a precise theory prediction of this observable.
[ { "created": "Fri, 15 May 2020 19:41:29 GMT", "version": "v1" }, { "created": "Mon, 3 May 2021 08:55:48 GMT", "version": "v2" }, { "created": "Mon, 5 Feb 2024 07:35:33 GMT", "version": "v3" } ]
2024-06-14
[ [ "Becker", "K.", "" ], [ "Caola", "F.", "" ], [ "Massironi", "A.", "" ], [ "Mistlberger", "B.", "" ], [ "Monni", "P. F.", "" ], [ "Chen", "X.", "" ], [ "Frixione", "S.", "" ], [ "Gehrmann", "T.", "" ], [ "Glover", "N.", "" ], [ "Hamilton", "K.", "" ], [ "Huss", "A.", "" ], [ "Jones", "S. P.", "" ], [ "Karlberg", "A.", "" ], [ "Kerner", "M.", "" ], [ "Kudashkin", "K.", "" ], [ "Lindert", "J. M.", "" ], [ "Luisoni", "G.", "" ], [ "Mangano", "M. L.", "" ], [ "Pozzorini", "S.", "" ], [ "Re", "E.", "" ], [ "Salam", "G. P.", "" ], [ "Vryonidou", "E.", "" ], [ "Wever", "C.", "" ] ]
Inclusive Higgs boson production at large transverse momentum is induced by different production channels. We focus on the leading production through gluon fusion, and perform a consistent combination of the state of the art calculations obtained in the infinite-top-mass effective theory at next-to-next-to-leading order (NNLO) and in the full Standard Model (SM) at next-to-leading order (NLO). We thus present approximate QCD predictions for this process at NNLO, and a study of the corresponding perturbative uncertainties. This calculation is then compared with those obtained with commonly used event generators, and we observe that the description of the considered kinematic regime provided by these tools is in good agreement with state of the art calculations. Finally, we present accurate predictions for other production channels such as vector boson fusion, and associated production with a gauge boson, and with a $t\bar{t}$ pair. We find that, at large transverse momentum, the contribution of other production modes is substantial, and therefore must be included for a precise theory prediction of this observable.
hep-ph/0101023
Andreas S. Kronfeld
Aida X. El-Khadra, Andreas S. Kronfeld, Paul B. Mackenzie, Sinead M. Ryan and James N. Simone
The Semileptonic Decays $B\to\pi l\nu$ and $D\to\pi l\nu$ from Lattice QCD
35 pp, 12 figs
Phys.Rev.D64:014502,2001
10.1103/PhysRevD.64.014502
FERMILAB-PUB-00/346-T
hep-ph hep-lat
null
We present a lattice QCD calculation of the form factors and differential decay rates for semileptonic decays of the heavy-light mesons $B$ and $D$ to the final state $\pi l\nu$. The results are obtained with three methodological improvements over previous lattice calculations: a matching procedure that reduces heavy-quark lattice artifacts, the first study of lattice-spacing dependence, and the introduction of kinematic cuts to reduce model dependence. We show that the main systematics are controllable (within the quenched approximation) and outline how the calculations could be improved to aid current experiments in the determination of~$|V_{ub}|$ and~$|V_{cd}|$.
[ { "created": "Tue, 2 Jan 2001 22:35:37 GMT", "version": "v1" } ]
2010-11-19
[ [ "El-Khadra", "Aida X.", "" ], [ "Kronfeld", "Andreas S.", "" ], [ "Mackenzie", "Paul B.", "" ], [ "Ryan", "Sinead M.", "" ], [ "Simone", "James N.", "" ] ]
We present a lattice QCD calculation of the form factors and differential decay rates for semileptonic decays of the heavy-light mesons $B$ and $D$ to the final state $\pi l\nu$. The results are obtained with three methodological improvements over previous lattice calculations: a matching procedure that reduces heavy-quark lattice artifacts, the first study of lattice-spacing dependence, and the introduction of kinematic cuts to reduce model dependence. We show that the main systematics are controllable (within the quenched approximation) and outline how the calculations could be improved to aid current experiments in the determination of~$|V_{ub}|$ and~$|V_{cd}|$.
0901.2236
Alfredo Urbano
Paolo Ciafaloni, Marco Picariello, Emilio Torrente-Lujan, Alfredo Urbano
Neutrino masses and tribimaximal mixing in the minimal renormalizable supersymmetric SU(5) grand unified model with A4 flavor symmetry
V1: 22 pages, V2: 16 pages, published version, results unchanged
Phys.Rev.D79:116010,2009
10.1103/PhysRevD.79.116010
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze all possible extensions of the recently proposed minimal renormalizable SUSY SU(5) grand unified model with the inclusion of an additional A4 flavor symmetry. We find that there are five possible cases but only one of them is phenomenologically interesting. We develop in detail such case and we show how the fermion masses and mixing angles come out. As a prediction we obtain the neutrino masses of order of 0.1 eV with an inverted hierarchy.
[ { "created": "Thu, 15 Jan 2009 12:27:52 GMT", "version": "v1" }, { "created": "Tue, 30 Jun 2009 09:58:32 GMT", "version": "v2" } ]
2009-07-09
[ [ "Ciafaloni", "Paolo", "" ], [ "Picariello", "Marco", "" ], [ "Torrente-Lujan", "Emilio", "" ], [ "Urbano", "Alfredo", "" ] ]
We analyze all possible extensions of the recently proposed minimal renormalizable SUSY SU(5) grand unified model with the inclusion of an additional A4 flavor symmetry. We find that there are five possible cases but only one of them is phenomenologically interesting. We develop in detail such case and we show how the fermion masses and mixing angles come out. As a prediction we obtain the neutrino masses of order of 0.1 eV with an inverted hierarchy.
1312.1796
Hongshi Zong
Yi-lun Du, Zhu-fang Cui, Yong-hui Xia and Hong-shi Zong
Discussions on the crossover property within the Nambu--Jona-Lasinio model
null
Phys. Rev. D 88, 114019 (2013)
10.1103/PhysRevD.88.114019
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, chiral symmetry breaking and its restoration are investigated in the mean field approximation of Nambu--Jona-Lasinio model. A first-order phase transition exists at low temperature, but is smeared out at high temperature. We discuss the rationality of using susceptibilities as the criteria to determine the crossover region as well as the critical point. Based on our results, it is found that to define a critical band instead of an exclusive line in this region might be a more suitable choice.
[ { "created": "Fri, 6 Dec 2013 08:17:42 GMT", "version": "v1" } ]
2013-12-09
[ [ "Du", "Yi-lun", "" ], [ "Cui", "Zhu-fang", "" ], [ "Xia", "Yong-hui", "" ], [ "Zong", "Hong-shi", "" ] ]
In this paper, chiral symmetry breaking and its restoration are investigated in the mean field approximation of Nambu--Jona-Lasinio model. A first-order phase transition exists at low temperature, but is smeared out at high temperature. We discuss the rationality of using susceptibilities as the criteria to determine the crossover region as well as the critical point. Based on our results, it is found that to define a critical band instead of an exclusive line in this region might be a more suitable choice.
2005.13968
Manjit Kaur Dr.
A. Kaur, M. Kaur and R. Aggarwal
Investigation of particle production in $h{\text -}A$ collisions using statistical distributions
21 pages, 10 figures 9 Tables
null
10.1142/S0218301321500075
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Study of the characteristic properties of charged particle production in hadron-nucleus collisions at high energies, by utilising the approaches from different statistical models is performed.~Predictions from different approaches using the Negative Binomial distribution, shifted Gompertz distribution, Weibull distribution and the Krasznovszky-Wagner distribution are utilised for a comparative study of the relative successes of these models.~These distributions derived from a variety of functional forms are based on either phenomenological parameterizations or some model of the underlying dynamics.~Some of these have have also been used to study the data at the LHC for both proton-proton and nucleus-nucleus collisions.~Various physical and derived observables have been used for the analysis.
[ { "created": "Thu, 28 May 2020 13:16:17 GMT", "version": "v1" }, { "created": "Fri, 21 Aug 2020 10:39:36 GMT", "version": "v2" } ]
2021-04-07
[ [ "Kaur", "A.", "" ], [ "Kaur", "M.", "" ], [ "Aggarwal", "R.", "" ] ]
Study of the characteristic properties of charged particle production in hadron-nucleus collisions at high energies, by utilising the approaches from different statistical models is performed.~Predictions from different approaches using the Negative Binomial distribution, shifted Gompertz distribution, Weibull distribution and the Krasznovszky-Wagner distribution are utilised for a comparative study of the relative successes of these models.~These distributions derived from a variety of functional forms are based on either phenomenological parameterizations or some model of the underlying dynamics.~Some of these have have also been used to study the data at the LHC for both proton-proton and nucleus-nucleus collisions.~Various physical and derived observables have been used for the analysis.
0712.3963
Rom\'an Linares
Roman Linares, Hugo A. Morales-Tecotl, Omar Pedraza
Casimir force for a scalar field in warped brane worlds
22 pages, 2 figures
Phys.Rev.D77:066012,2008
10.1103/PhysRevD.77.066012
null
hep-ph
null
In looking for imprints of extra dimensions in brane world models one usually builts these so that they are compatible with known low energy physics and thus focuses on high energy effects. Nevertheless, just as submillimeter Newton's law tests probe the mode structure of gravity other low energy tests might apply to matter. As a model example, in this work we determine the 4D Casimir force corresponding to a scalar field subject to Dirichlet boundary conditions on two parallel planes lying within the single brane of a Randall-Sundrum scenario extended by one compact extra dimension. Using the Green's function method such a force picks the contribution of each field mode as if it acted individually but with a weight given by the square of the mode wave functions on the brane. In the low energy regime one regains the standard 4D Casimir force that is associated to a zero mode in the massless case or to a quasilocalized or resonant mode in the massive one whilst the effect of the extra dimensions gets encoded as an additional term.
[ { "created": "Mon, 24 Dec 2007 02:27:20 GMT", "version": "v1" } ]
2008-11-26
[ [ "Linares", "Roman", "" ], [ "Morales-Tecotl", "Hugo A.", "" ], [ "Pedraza", "Omar", "" ] ]
In looking for imprints of extra dimensions in brane world models one usually builts these so that they are compatible with known low energy physics and thus focuses on high energy effects. Nevertheless, just as submillimeter Newton's law tests probe the mode structure of gravity other low energy tests might apply to matter. As a model example, in this work we determine the 4D Casimir force corresponding to a scalar field subject to Dirichlet boundary conditions on two parallel planes lying within the single brane of a Randall-Sundrum scenario extended by one compact extra dimension. Using the Green's function method such a force picks the contribution of each field mode as if it acted individually but with a weight given by the square of the mode wave functions on the brane. In the low energy regime one regains the standard 4D Casimir force that is associated to a zero mode in the massless case or to a quasilocalized or resonant mode in the massive one whilst the effect of the extra dimensions gets encoded as an additional term.
hep-ph/9511365
Paulo Bedaque
Paulo F. Bedaque (MIT,USA)
Chiral perturbation theory analysis of baryon temperature mass shifts
8 pages + 4 uuencoded figures (or available from the Author upon request), REVTEX. Figures previously corrupted are corrected
Phys.Lett.B387:1-8,1996
10.1016/0370-2693(96)00985-9
null
hep-ph nucl-th
null
We compute the finite temperature pole mass shifts of the octet and decuplet baryons using heavy baryon chiral perturbation theory and the 1/N_c expansion, where N_c is the number of QCD colors. We consider temperatures of the order of the pion mass m_\pi, and truncate the chiral and 1/N_c expansions assuming that m_\pi \sim 1/N_c. There are three scales in the problem: the temperature T, the pion mass m_\pi, and the octet--decuplet mass difference. Therefore, the result is not simply a power series in T. We find that the nucleon and \Delta temperature mass shifts are opposite in sign, and that their mass difference changes by 20% in the temperature range 90 MeV < T < 130 MeV, that is the range where the freeze out in relativistic heavy ion collisions is expected to occur. We argue that our results are insensitive to the neglect of 1/N_c- supressed effects; the main purpose of the 1/N_c expansion in this work is to justify our treatment of the decuplet states.
[ { "created": "Sat, 18 Nov 1995 00:23:22 GMT", "version": "v1" }, { "created": "Thu, 30 Nov 1995 21:00:04 GMT", "version": "v2" } ]
2014-11-17
[ [ "Bedaque", "Paulo F.", "", "MIT,USA" ] ]
We compute the finite temperature pole mass shifts of the octet and decuplet baryons using heavy baryon chiral perturbation theory and the 1/N_c expansion, where N_c is the number of QCD colors. We consider temperatures of the order of the pion mass m_\pi, and truncate the chiral and 1/N_c expansions assuming that m_\pi \sim 1/N_c. There are three scales in the problem: the temperature T, the pion mass m_\pi, and the octet--decuplet mass difference. Therefore, the result is not simply a power series in T. We find that the nucleon and \Delta temperature mass shifts are opposite in sign, and that their mass difference changes by 20% in the temperature range 90 MeV < T < 130 MeV, that is the range where the freeze out in relativistic heavy ion collisions is expected to occur. We argue that our results are insensitive to the neglect of 1/N_c- supressed effects; the main purpose of the 1/N_c expansion in this work is to justify our treatment of the decuplet states.
2310.17978
Shohei Takada
Shota Kikuchi, Tatsuo Kobayashi, Kaito Nasu, Shohei Takada, Hikaru Uchida
$Sp(6,Z)$ modular symmetry in flavor structures: quark flavor models and Siegel modular forms for $\widetilde{\Delta}(96)$
54 pages
null
null
EPHOU-23-018
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
We study an approach to construct Siegel modular forms from $Sp(6,Z)$. Zero-mode wave functions on $T^6$ with magnetic flux background behave Siegel modular forms at the origin. Then $T$-symmetries partially break depending on the form of background magnetic flux. We study the background such that three $T$-symmetries $T_I$, $T_{II}$ and $T_{III}$ as well as the $S$-symmetry remain.Consequently, we obtain Siegel modular forms with three moduli parameters $(\omega_1,\omega_2,\omega_3)$, which are multiplets of finite modular groups. We show several examples. As one of examples, we study Siegel modular forms for $\widetilde{\Delta}(96)$ in detail. Then, as a phenomenological applicantion, we study quark flavor models using Siegel modular forms for $\widetilde{\Delta}(96)$. Around the cusp, $\omega_1=i\infty$, the Siegel modular forms have hierarchical values depending on their $T_I$-charges. We show the deviation of $\omega_1$ from the cusp can generate large quark mass hierarchies without fine-tuning. Furthermore CP violation is induced by deviation of $\omega_2$ from imaginary axis.
[ { "created": "Fri, 27 Oct 2023 08:48:51 GMT", "version": "v1" } ]
2023-10-30
[ [ "Kikuchi", "Shota", "" ], [ "Kobayashi", "Tatsuo", "" ], [ "Nasu", "Kaito", "" ], [ "Takada", "Shohei", "" ], [ "Uchida", "Hikaru", "" ] ]
We study an approach to construct Siegel modular forms from $Sp(6,Z)$. Zero-mode wave functions on $T^6$ with magnetic flux background behave Siegel modular forms at the origin. Then $T$-symmetries partially break depending on the form of background magnetic flux. We study the background such that three $T$-symmetries $T_I$, $T_{II}$ and $T_{III}$ as well as the $S$-symmetry remain.Consequently, we obtain Siegel modular forms with three moduli parameters $(\omega_1,\omega_2,\omega_3)$, which are multiplets of finite modular groups. We show several examples. As one of examples, we study Siegel modular forms for $\widetilde{\Delta}(96)$ in detail. Then, as a phenomenological applicantion, we study quark flavor models using Siegel modular forms for $\widetilde{\Delta}(96)$. Around the cusp, $\omega_1=i\infty$, the Siegel modular forms have hierarchical values depending on their $T_I$-charges. We show the deviation of $\omega_1$ from the cusp can generate large quark mass hierarchies without fine-tuning. Furthermore CP violation is induced by deviation of $\omega_2$ from imaginary axis.
1307.1958
Ignasi Rosell
Antonio Pich, Ignasi Rosell and Juan Jose Sanz-Cillero
Strongly Coupled Models with a Higgs-like Boson
5 pages, 2 figures. Talk given at LHCP 2013, the Large Hadron Collider Physics Conference, May 13-18th (2013), Barcelona (Spain)
null
10.1051/epjconf/20136019009
IFIC/13-38, FTUV/13-0708, FTUAM-13-18, IFT-UAM/CSIC-13-079
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Considering the one-loop calculation of the oblique S and T parameters, we have presented a study of the viability of strongly-coupled scenarios of electroweak symmetry breaking with a light Higgs-like boson. The calculation has been done by using an effective Lagrangian, being short-distance constraints and dispersive relations the main ingredients of the estimation. Contrary to a widely spread believe, we have demonstrated that strongly coupled electroweak models with massive resonances are not in conflict with experimental constraints on these parameters and the recently observed Higgs-like resonance. So there is room for these models, but they are stringently constrained. The vector and axial-vector states should be heavy enough (with masses above the TeV scale), the mass splitting between them is highly preferred to be small and the Higgs-like scalar should have a WW coupling close to the Standard Model one. It is important to stress that these conclusions do not depend critically on the inclusion of the second Weinberg sum rule.
[ { "created": "Mon, 8 Jul 2013 06:41:26 GMT", "version": "v1" } ]
2015-06-16
[ [ "Pich", "Antonio", "" ], [ "Rosell", "Ignasi", "" ], [ "Sanz-Cillero", "Juan Jose", "" ] ]
Considering the one-loop calculation of the oblique S and T parameters, we have presented a study of the viability of strongly-coupled scenarios of electroweak symmetry breaking with a light Higgs-like boson. The calculation has been done by using an effective Lagrangian, being short-distance constraints and dispersive relations the main ingredients of the estimation. Contrary to a widely spread believe, we have demonstrated that strongly coupled electroweak models with massive resonances are not in conflict with experimental constraints on these parameters and the recently observed Higgs-like resonance. So there is room for these models, but they are stringently constrained. The vector and axial-vector states should be heavy enough (with masses above the TeV scale), the mass splitting between them is highly preferred to be small and the Higgs-like scalar should have a WW coupling close to the Standard Model one. It is important to stress that these conclusions do not depend critically on the inclusion of the second Weinberg sum rule.
hep-ph/9905429
Stephen J. Puglia
M.J. Ramsey-Musolf
Electric Dipole Moments and the Mass Scale of New T-Violating, P-Conserving Interactions
9 pages, 2 figures. To appear in PRL
Phys.Rev.Lett. 83 (1999) 3997-4000; Erratum-ibid. 84 (2000) 5681
10.1103/PhysRevLett.83.3997
null
hep-ph
null
We consider the implications of experimental limits on the permanent electric dipole moment (EDM) of the electron and neutron for possible new parity-conserving (PC) time-reversal violating (TV) interactions. We show that the constraints derived from one-loop contributions to the EDM exceed previously reported two-loop limits by more than an order of magnitude and imply a lower bound on the new TVPC mass scale $\lamtv$ of 100 TeV for new TVPC strong interactions. These results imply a value of $10^{-15}$ or smaller for the ratio of low-energy TVPC matrix elements to those of the residual strong interaction.
[ { "created": "Thu, 20 May 1999 23:13:38 GMT", "version": "v1" }, { "created": "Wed, 20 Oct 1999 15:57:11 GMT", "version": "v2" } ]
2009-10-31
[ [ "Ramsey-Musolf", "M. J.", "" ] ]
We consider the implications of experimental limits on the permanent electric dipole moment (EDM) of the electron and neutron for possible new parity-conserving (PC) time-reversal violating (TV) interactions. We show that the constraints derived from one-loop contributions to the EDM exceed previously reported two-loop limits by more than an order of magnitude and imply a lower bound on the new TVPC mass scale $\lamtv$ of 100 TeV for new TVPC strong interactions. These results imply a value of $10^{-15}$ or smaller for the ratio of low-energy TVPC matrix elements to those of the residual strong interaction.
0710.2809
Barbara Mele
Barbara Mele
Rescuing H -> bb in VBF at the LHC by requiring a central photon
5 pages, 1 figure, invited talk at IFAE 2007, April 11-13, Naples, Italy, to appear in the Proceedings
null
null
null
hep-ph
null
The LHC potential for a measurement of the Higgs boson coupling to the b quark in the standard model is not well established yet. We show that requiring a large transverse momentum photon in the light Higgs boson production via vector-boson fusion (with subsequent H->bb decay) could provide a further handle on the Hbb coupling determination, and on the measurement of the HWW coupling as well.
[ { "created": "Mon, 15 Oct 2007 13:33:05 GMT", "version": "v1" } ]
2007-10-16
[ [ "Mele", "Barbara", "" ] ]
The LHC potential for a measurement of the Higgs boson coupling to the b quark in the standard model is not well established yet. We show that requiring a large transverse momentum photon in the light Higgs boson production via vector-boson fusion (with subsequent H->bb decay) could provide a further handle on the Hbb coupling determination, and on the measurement of the HWW coupling as well.
hep-ph/9211328
Osamu Yasuda
Kazuhito Iida, Hisakazu Minakata and Osamu Yasuda
A test of the equivalence principle by long-baseline neutrino-oscillation experiments
LaTeX, 13 pages and 5 figures appended as PostScript files, TMUP-HEL-9207
Mod. Phys. Lett. A8 (1993) 1037-1046
10.1142/S021773239300252X
null
hep-ph
null
We show that a breakdown of the universality of the gravitational couplings to different neutrino flavors can be tested in long-baseline neutrino-oscillation experiments. In particular we have analyzed in detail a proposed experiment at SOUDAN 2 with $\nu_\mu$ beams from the Fermilab Main Injector. It turns out that we can study both masses of neutrinos and such a breakdown with sensitivity to the order of $10^{-14}$ by investigating the energy spectrum of the resulting muons.
[ { "created": "Sat, 28 Nov 1992 14:55:02 GMT", "version": "v1" } ]
2015-06-25
[ [ "Iida", "Kazuhito", "" ], [ "Minakata", "Hisakazu", "" ], [ "Yasuda", "Osamu", "" ] ]
We show that a breakdown of the universality of the gravitational couplings to different neutrino flavors can be tested in long-baseline neutrino-oscillation experiments. In particular we have analyzed in detail a proposed experiment at SOUDAN 2 with $\nu_\mu$ beams from the Fermilab Main Injector. It turns out that we can study both masses of neutrinos and such a breakdown with sensitivity to the order of $10^{-14}$ by investigating the energy spectrum of the resulting muons.
hep-ph/0404237
Jose Santiago
S. A. Abel, J. Santiago
Constraining the string scale: from Planck to Weak and back again
Invited review aimed at an experimental audience
J.Phys.G30:R83-R111,2004
10.1088/0954-3899/30/3/R01
null
hep-ph hep-ex
null
String and field theory ideas have greatly influenced each other since the so called second string revolution. We review this interrelation paying particular attention to its phenomenological implications. Our guiding principle is the radical shift in the way that we think about the fundamental scale, in particular the way in which string models have been able to accommodate values from the Planck $M_\mathrm{Pl}\sim 10^{18}$ GeV down to the electroweak scale $M_{EW}\sim $ TeV.
[ { "created": "Tue, 27 Apr 2004 12:11:50 GMT", "version": "v1" } ]
2010-01-08
[ [ "Abel", "S. A.", "" ], [ "Santiago", "J.", "" ] ]
String and field theory ideas have greatly influenced each other since the so called second string revolution. We review this interrelation paying particular attention to its phenomenological implications. Our guiding principle is the radical shift in the way that we think about the fundamental scale, in particular the way in which string models have been able to accommodate values from the Planck $M_\mathrm{Pl}\sim 10^{18}$ GeV down to the electroweak scale $M_{EW}\sim $ TeV.
1110.1238
M. E. Carrington
M.E. Carrington
Transport Coefficients and nPI Methods
10 pages, 5 figures, contribution to the proceedings of the HIC for FAIR Workshop and XXVIII Max Born Symposium "Three Days on Quarkyonic Island," Wroclaw, May 19-21, 2011
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Transport coefficients can be obtained from 2-point correlators using the Kubo formulae. It has been shown that the full leading order result for electrical conductivity and (QCD) shear viscosity is contained in the re-summed 2-point function that is obtained from the 3-loop 3PI effective action. The theory produces all leading order contributions without the necessity for power counting, and in this sense it provides a natural framework for the calculation and suggests that one can calculate the next-to-leading contribution to transport coefficients from the 4-loop 4PI effective action. The integral equations have been derived for shear viscosity for a scalar theory with cubic and quartic interactions, with a non-vanishing field expectation value. We review these results, and explain how the calculation could be done at higher orders.
[ { "created": "Thu, 6 Oct 2011 12:15:00 GMT", "version": "v1" } ]
2011-10-07
[ [ "Carrington", "M. E.", "" ] ]
Transport coefficients can be obtained from 2-point correlators using the Kubo formulae. It has been shown that the full leading order result for electrical conductivity and (QCD) shear viscosity is contained in the re-summed 2-point function that is obtained from the 3-loop 3PI effective action. The theory produces all leading order contributions without the necessity for power counting, and in this sense it provides a natural framework for the calculation and suggests that one can calculate the next-to-leading contribution to transport coefficients from the 4-loop 4PI effective action. The integral equations have been derived for shear viscosity for a scalar theory with cubic and quartic interactions, with a non-vanishing field expectation value. We review these results, and explain how the calculation could be done at higher orders.
hep-ph/0607293
Christian Fischer
Reinhard Alkofer, Christian S. Fischer and Felipe J. Llanes-Estrada
Dynamically induced scalar quark confinement
12 pages, 2 figures; v2: clarifications added and typos corrected, version to be published by MPLA
Mod.Phys.Lett.A23:1105-1113,2008
10.1142/S021773230802700X
null
hep-ph hep-lat hep-th nucl-th
null
We employ a functional approach to investigate the confinement problem in quenched Landau gauge QCD. We demonstrate analytically that a linear rising potential between massive quarks is generated by infrared singularities in the dressed quark-gluon vertex. The selfconsistent mechanism that generates these singularities is driven by the scalar Dirac amplitudes of the full vertex and the quark propagator. These can only be present when chiral symmetry is broken. We have thus uncovered a novel mechanism that directly links chiral symmetry breaking with confinement.
[ { "created": "Wed, 26 Jul 2006 14:50:52 GMT", "version": "v1" }, { "created": "Wed, 7 May 2008 19:02:05 GMT", "version": "v2" } ]
2010-10-27
[ [ "Alkofer", "Reinhard", "" ], [ "Fischer", "Christian S.", "" ], [ "Llanes-Estrada", "Felipe J.", "" ] ]
We employ a functional approach to investigate the confinement problem in quenched Landau gauge QCD. We demonstrate analytically that a linear rising potential between massive quarks is generated by infrared singularities in the dressed quark-gluon vertex. The selfconsistent mechanism that generates these singularities is driven by the scalar Dirac amplitudes of the full vertex and the quark propagator. These can only be present when chiral symmetry is broken. We have thus uncovered a novel mechanism that directly links chiral symmetry breaking with confinement.
1205.2752
Giulia Ricciardi
Giulia Ricciardi
CP violation with Bs
4 pages. To appear in Proceedings of Rencontres de Moriond, QCD and High Energy Interactions, La Thuile, March 10-17, 2012
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The observation of CP violation effects is becoming more and more significant in a variety of channels, due to the impressive experimental effort of the last years. We review recent progress in Bs semileptonic decays and in Bs decays into CP eigenstates.
[ { "created": "Sat, 12 May 2012 08:17:11 GMT", "version": "v1" } ]
2012-05-15
[ [ "Ricciardi", "Giulia", "" ] ]
The observation of CP violation effects is becoming more and more significant in a variety of channels, due to the impressive experimental effort of the last years. We review recent progress in Bs semileptonic decays and in Bs decays into CP eigenstates.
hep-ph/0005212
Gideon Alexander
Gideon Alexander and Edward Sarkisyan
The effect of many sources on the genuine multiparticle correlations
null
Phys.Lett. B487 (2000) 215-223
10.1016/S0370-2693(00)00820-0
TAUP 2630-2000
hep-ph
null
We report on a study aimed to explore the dependence of the genuine multiparticle correlations on the number of sources when the influence of other possible factors during multihadron production are avoided. The analysis utilised the normalised cumulants calculated in three-dimensional phase space of the reaction ee -> Z -> hadrons using a large Monte Carlo sample. The multi-sources events were simulated by overlaying a few independent single ee annihilation events. It was found that as the number of sources increases, the cumulants do not change significantly their structure, but those of an order higher than two decrease fast in their magnitude. This reduction and its amount can be understood in terms of combinatorial considerations of source mixing which dilutes the correlations. The diminishing of the genuine correlations is consistent with recent cumulant measurements in hadron and nucleus induced reactions and should also be relevant to other dynamical correlations like the Bose-Einstein one, in ee -> WW -> hadrons and in nucleus-nucleus reactions.
[ { "created": "Mon, 22 May 2000 07:12:25 GMT", "version": "v1" }, { "created": "Mon, 26 Jun 2000 10:57:48 GMT", "version": "v2" }, { "created": "Tue, 27 Jun 2000 06:54:33 GMT", "version": "v3" } ]
2016-09-06
[ [ "Alexander", "Gideon", "" ], [ "Sarkisyan", "Edward", "" ] ]
We report on a study aimed to explore the dependence of the genuine multiparticle correlations on the number of sources when the influence of other possible factors during multihadron production are avoided. The analysis utilised the normalised cumulants calculated in three-dimensional phase space of the reaction ee -> Z -> hadrons using a large Monte Carlo sample. The multi-sources events were simulated by overlaying a few independent single ee annihilation events. It was found that as the number of sources increases, the cumulants do not change significantly their structure, but those of an order higher than two decrease fast in their magnitude. This reduction and its amount can be understood in terms of combinatorial considerations of source mixing which dilutes the correlations. The diminishing of the genuine correlations is consistent with recent cumulant measurements in hadron and nucleus induced reactions and should also be relevant to other dynamical correlations like the Bose-Einstein one, in ee -> WW -> hadrons and in nucleus-nucleus reactions.
hep-ph/0402078
Peter Zeiler Skands
T. Sj\"ostrand and P. Skands
Multiple Interactions and the Structure of Beam Remnants
69pp, 33 figures
JHEP 0403:053,2004
10.1088/1126-6708/2004/03/053
LU-TP-04-08
hep-ph
null
Recent experimental data have established some of the basic features of multiple interactions in hadron-hadron collisions. The emphasis is therefore now shifting, to one of exploring more detailed aspects. Starting from a brief review of the current situation, a next-generation model is developed, wherein a detailed account is given of correlated flavour, colour, longitudinal and transverse momentum distributions, encompassing both the partons initiating perturbative interactions and the partons left in the beam remnants. Some of the main features are illustrated for the Tevatron and the LHC.
[ { "created": "Sat, 7 Feb 2004 22:40:24 GMT", "version": "v1" }, { "created": "Wed, 19 May 2004 13:05:28 GMT", "version": "v2" } ]
2009-12-15
[ [ "Sjöstrand", "T.", "" ], [ "Skands", "P.", "" ] ]
Recent experimental data have established some of the basic features of multiple interactions in hadron-hadron collisions. The emphasis is therefore now shifting, to one of exploring more detailed aspects. Starting from a brief review of the current situation, a next-generation model is developed, wherein a detailed account is given of correlated flavour, colour, longitudinal and transverse momentum distributions, encompassing both the partons initiating perturbative interactions and the partons left in the beam remnants. Some of the main features are illustrated for the Tevatron and the LHC.
1812.09682
Martin Rohrmoser
Martin Rohrmoser, Pol Gossiaux, Thierry Gousset, Joerg Aichelin, Iurii Karpenko
Effects of jet-medium interactions on angular correlations of jet-particle pairs at different energy scales
proceedings for a seminar talk at the "Hard Probes 2018" conference in Aix Les Bains, 4 pages, 1 figure
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The energy-loss of hard probes within the hot and dense medium of a quark gluon plasma (QGP) can be described by theoretical models based on radiative energy loss as well as combinations of collisional and radiative energy loss. In a search for observables that allow to disentangle these energy-loss mechanisms, we introduced a set of effective models that allows to investigate the consequences on jets of both types of jet-medium interactions within a consistent framework. We particularly studied angular jet-broadening via angular two-particle correlations. Distinguishing contributions from pairs at different scales of particle momenta, we found qualitative differences between radiative and collisional approaches.
[ { "created": "Sun, 23 Dec 2018 10:09:14 GMT", "version": "v1" } ]
2018-12-27
[ [ "Rohrmoser", "Martin", "" ], [ "Gossiaux", "Pol", "" ], [ "Gousset", "Thierry", "" ], [ "Aichelin", "Joerg", "" ], [ "Karpenko", "Iurii", "" ] ]
The energy-loss of hard probes within the hot and dense medium of a quark gluon plasma (QGP) can be described by theoretical models based on radiative energy loss as well as combinations of collisional and radiative energy loss. In a search for observables that allow to disentangle these energy-loss mechanisms, we introduced a set of effective models that allows to investigate the consequences on jets of both types of jet-medium interactions within a consistent framework. We particularly studied angular jet-broadening via angular two-particle correlations. Distinguishing contributions from pairs at different scales of particle momenta, we found qualitative differences between radiative and collisional approaches.
2302.03324
Duc Ninh Le
Thi Nhung Dao, Duc Ninh Le
Enhancing the doubly-longitudinal polarization in WZ production at the LHC
13 pages, 3 figures, 3 tables. arXiv admin note: text overlap with arXiv:2208.09232
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We present new results for the theoretical prediction of doubly-polarized cross sections of $WZ$ events at the LHC using leptonic decays. Compared to the previous studies, two new kinematic cuts are considered. These cuts are designed to enhance the doubly-longitudinal (LL) polarization and, at the same time, study the Radiation Amplitude Zero effect. We found a new cut on the rapidity separation between the $Z$ boson and the electron from the $W$ decay which makes the LL fraction largest, namely $|\Delta y_{Z,e}| < 0.5$. This result is obtained at the next-to-leading order in the strong and electroweak couplings.
[ { "created": "Tue, 7 Feb 2023 09:04:07 GMT", "version": "v1" } ]
2023-02-08
[ [ "Dao", "Thi Nhung", "" ], [ "Le", "Duc Ninh", "" ] ]
We present new results for the theoretical prediction of doubly-polarized cross sections of $WZ$ events at the LHC using leptonic decays. Compared to the previous studies, two new kinematic cuts are considered. These cuts are designed to enhance the doubly-longitudinal (LL) polarization and, at the same time, study the Radiation Amplitude Zero effect. We found a new cut on the rapidity separation between the $Z$ boson and the electron from the $W$ decay which makes the LL fraction largest, namely $|\Delta y_{Z,e}| < 0.5$. This result is obtained at the next-to-leading order in the strong and electroweak couplings.
hep-ph/9703341
Kiselev
A.V.Berezhnoy, V.V.Kiselev, A.K.Likhoded, A.I.Onischenko
$B_c$ Meson at LHC
27 pages, Latex file, epsf-style, 6 ps-figures
Phys.Atom.Nucl.60:1729-1740,1997; Yad.Fiz.60N10:1889-1900.1997
null
IHEP 97-2
hep-ph
null
In the framework of perturbative QCD and potential models of heavy quarkonium, total cross-sections and differential characteristics of hadronic production for different spin states of the $B_c$-meson family are calculated at energies of LHC. Theoretical predictions for masses and branching ratios of $B_c$ decays are given, which allows one to make estimates for an expected number of reconstructed events with $B_c$.
[ { "created": "Mon, 17 Mar 1997 15:58:05 GMT", "version": "v1" } ]
2014-11-17
[ [ "Berezhnoy", "A. V.", "" ], [ "Kiselev", "V. V.", "" ], [ "Likhoded", "A. K.", "" ], [ "Onischenko", "A. I.", "" ] ]
In the framework of perturbative QCD and potential models of heavy quarkonium, total cross-sections and differential characteristics of hadronic production for different spin states of the $B_c$-meson family are calculated at energies of LHC. Theoretical predictions for masses and branching ratios of $B_c$ decays are given, which allows one to make estimates for an expected number of reconstructed events with $B_c$.
hep-ph/0102133
Vadim Guzey
V. Guzey (Adelaide U.), K. Saito (Tohoku Coll., Pharmacy), M. Strikman (Penn State U.), A.W. Thomas and K. Tsushima (Adelaide U.)
Non-singlet structure function of the 3He-3H system and divergence of the Gottfried integral
29 pages, 6 figures, RevTex
Phys.Rev.D64:054503,2001
10.1103/PhysRevD.64.054503
ADP-01-03/T438
hep-ph hep-ex nucl-ex nucl-th
null
We study shadowing and antishadowing corrections to the flavor non-singlet structure function F_2(3He)-F_2(3H) and show that the difference between the one-particle density distributions of 3He and 3H plays an important role at very small x. We find that the flavor non-singlet structure function in these mirror nuclei is enhanced at small x by nuclear shadowing, which increases the nuclear Gottfried integral, integrated from 10^{-4} to 1, by 11-36 %. When integrated from zero, the Gottfried integral is divergent for these mirror nuclei. It seems likely that, as a consequence of charge symmetry breaking, this may also apply to the proton-neutron system.
[ { "created": "Mon, 12 Feb 2001 00:22:35 GMT", "version": "v1" } ]
2010-02-17
[ [ "Guzey", "V.", "", "Adelaide U." ], [ "Saito", "K.", "", "Tohoku Coll., Pharmacy" ], [ "Strikman", "M.", "", "Penn State U." ], [ "Thomas", "A. W.", "", "Adelaide U." ], [ "Tsushima", "K.", "", "Adelaide U." ] ]
We study shadowing and antishadowing corrections to the flavor non-singlet structure function F_2(3He)-F_2(3H) and show that the difference between the one-particle density distributions of 3He and 3H plays an important role at very small x. We find that the flavor non-singlet structure function in these mirror nuclei is enhanced at small x by nuclear shadowing, which increases the nuclear Gottfried integral, integrated from 10^{-4} to 1, by 11-36 %. When integrated from zero, the Gottfried integral is divergent for these mirror nuclei. It seems likely that, as a consequence of charge symmetry breaking, this may also apply to the proton-neutron system.
0907.0949
Andrea Achilli
A. Achilli, R. Godbole, A. Grau, G. Pancheri, Y.N. Srivastava
QCD Mini-jet contribution to the total cross section
7 pages, 3 figures, presented at MPI08, Perugia, October 27-31, 2008
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the predictions of a model for proton-proton total cross-section at LHC. It takes into account both hard partonic processes and soft gluon emission effects to describe the proper high energy behavior and to respect the Froissart bound.
[ { "created": "Mon, 6 Jul 2009 09:49:41 GMT", "version": "v1" } ]
2009-07-07
[ [ "Achilli", "A.", "" ], [ "Godbole", "R.", "" ], [ "Grau", "A.", "" ], [ "Pancheri", "G.", "" ], [ "Srivastava", "Y. N.", "" ] ]
We present the predictions of a model for proton-proton total cross-section at LHC. It takes into account both hard partonic processes and soft gluon emission effects to describe the proper high energy behavior and to respect the Froissart bound.
1302.0960
Satyanarayan Mukhopadhyay
Kaoru Hagiwara, Satyanarayan Mukhopadhyay
Azimuthal correlation among jets produced in association with a bottom or top quark pair at the LHC
15 pages, 5 figures; v2: minor additions to text, references added, version as published in JHEP
JHEP05(2013)019
10.1007/JHEP05(2013)019
KEK-TH-1597, IPMU 13-0025
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Angular correlation of jets produced in association with a massive scalar, vector or tensor boson is crucial in the determination of their spin and CP properties. We study jet angular correlations in events with a high mass bottom quark pair or a top quark pair and two jets at the LHC, whose cross-section is dominated by the virtual gluon fusion sub-processes when appropriate kinematic selection cuts (vector-boson fusion cuts) are applied. We evaluate helicity amplitudes for sub-processes initiated by qq, qg and gg collisions in the limit where the intermediate gluons are collinear to the initial partons. We first obtain a general expression for the azimuthal angle correlations among the dijets and t t-bar or b b-bar, in terms of the gg to t t-bar or b b-bar helicity amplitudes in the real gluon approximation of the full matrix elements, and find simple analytic expressions in the two kinematic limits, the production of a heavy quark pair near the threshold, and in the relativistic limit where the invariant mass of the heavy quark pair is much larger than the quark mass. For b b-bar + 2 jets we find strong azimuthal angle correlations which are distinct from those expected for events with a CP-even or odd scalar boson which may decay into a b b-bar pair. For t t-bar + 2 jets we find that the angular correlations are similar to that of a CP-odd scalar+2 jets near the threshold M_(t t-bar) ~ 2 m_t, while in the relativistic limit they resemble the distribution for b b-bar + 2 jets. These correlations in the standard QCD processes will help establish the experimental technique to measure the spin and CP properties of new particles produced via gluon fusion at the LHC.
[ { "created": "Tue, 5 Feb 2013 08:46:42 GMT", "version": "v1" }, { "created": "Tue, 7 May 2013 07:39:39 GMT", "version": "v2" } ]
2013-05-08
[ [ "Hagiwara", "Kaoru", "" ], [ "Mukhopadhyay", "Satyanarayan", "" ] ]
Angular correlation of jets produced in association with a massive scalar, vector or tensor boson is crucial in the determination of their spin and CP properties. We study jet angular correlations in events with a high mass bottom quark pair or a top quark pair and two jets at the LHC, whose cross-section is dominated by the virtual gluon fusion sub-processes when appropriate kinematic selection cuts (vector-boson fusion cuts) are applied. We evaluate helicity amplitudes for sub-processes initiated by qq, qg and gg collisions in the limit where the intermediate gluons are collinear to the initial partons. We first obtain a general expression for the azimuthal angle correlations among the dijets and t t-bar or b b-bar, in terms of the gg to t t-bar or b b-bar helicity amplitudes in the real gluon approximation of the full matrix elements, and find simple analytic expressions in the two kinematic limits, the production of a heavy quark pair near the threshold, and in the relativistic limit where the invariant mass of the heavy quark pair is much larger than the quark mass. For b b-bar + 2 jets we find strong azimuthal angle correlations which are distinct from those expected for events with a CP-even or odd scalar boson which may decay into a b b-bar pair. For t t-bar + 2 jets we find that the angular correlations are similar to that of a CP-odd scalar+2 jets near the threshold M_(t t-bar) ~ 2 m_t, while in the relativistic limit they resemble the distribution for b b-bar + 2 jets. These correlations in the standard QCD processes will help establish the experimental technique to measure the spin and CP properties of new particles produced via gluon fusion at the LHC.
2312.05992
Tisa Biswas
Tisa Biswas
Probing the Interactions of Axion-Like Particles with Electroweak Bosons and the Higgs Boson in the High Energy Regime at LHC
33 pages, 16 figures, 7 Tables; version accepted for publication in JHEP
JHEP 05 (2024) 081
10.1007/JHEP05(2024)081
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study the interactions of Axion-Like Particles (ALPs) with the Standard Model particles, aiming to probe their phenomenology via non-resonant searches at the LHC. These interactions are mediated by higher dimensional effective operators within two possible frameworks of linearly and non-linearly realised electroweak symmetry breaking. We consider the ALPs to be light enough to be produced on-shell and exploit their derivative couplings with the SM Higgs boson and the gauge bosons. We will use the high momentum transfer processes, namely $hZ, Z\gamma, WW$ and $WW\gamma$ production from $pp$ collisions. We derive upper limits on the gauge-invariant interactions of ALPs with the electroweak bosons and/or Higgs boson that contribute to these processes, from the re-interpretation of the latest Run 2 available LHC data. The constraints we obtain are strong for ALP masses below 100 GeV. These allowed effective interactions in the ALP parameter space yield better significance at HL-LHC and thus, offer promising avenues for subsequent studies. Furthermore, we augment our cut-based analysis with gradient-boosted decision trees, which improve the statistical significance distinctly across these interaction channels. We briefly compare the results with the complementary probe of these couplings via direct production of ALPs in association with the Higgs boson or a vector boson.
[ { "created": "Sun, 10 Dec 2023 20:41:40 GMT", "version": "v1" }, { "created": "Mon, 8 Apr 2024 17:54:52 GMT", "version": "v2" } ]
2024-05-09
[ [ "Biswas", "Tisa", "" ] ]
We study the interactions of Axion-Like Particles (ALPs) with the Standard Model particles, aiming to probe their phenomenology via non-resonant searches at the LHC. These interactions are mediated by higher dimensional effective operators within two possible frameworks of linearly and non-linearly realised electroweak symmetry breaking. We consider the ALPs to be light enough to be produced on-shell and exploit their derivative couplings with the SM Higgs boson and the gauge bosons. We will use the high momentum transfer processes, namely $hZ, Z\gamma, WW$ and $WW\gamma$ production from $pp$ collisions. We derive upper limits on the gauge-invariant interactions of ALPs with the electroweak bosons and/or Higgs boson that contribute to these processes, from the re-interpretation of the latest Run 2 available LHC data. The constraints we obtain are strong for ALP masses below 100 GeV. These allowed effective interactions in the ALP parameter space yield better significance at HL-LHC and thus, offer promising avenues for subsequent studies. Furthermore, we augment our cut-based analysis with gradient-boosted decision trees, which improve the statistical significance distinctly across these interaction channels. We briefly compare the results with the complementary probe of these couplings via direct production of ALPs in association with the Higgs boson or a vector boson.
hep-ph/0102248
Christof Wetterich
C.Wetterich
Phase transition between three- and two-flavor QCD?
published version, new section on heavy quark potential,29 pages,LaTex
null
null
HD-THEP-01-09
hep-ph
null
We explore the possibility that QCD may undergo a phase transition as a function of the strange quark mass. This would hint towards models with ``spontaneous color symmetry breaking'' in the vacuum. For two light quark flavors we classify possible colored quark-antiquark, diquark and gluon condensates that are compatible with a spectrum of integer charged states and conserved isospin and baryon number. The ``quark mass phase transition'' would be linked to an unusual realization of baryon number in QCD$_2$ and could be tested in lattice simulations. We emphasize, however, that at the present stage the Higgs picture of the vacuum cannot predict a quark mass phase transition - a smooth crossover remains as a realistic alternative. Implications of the Higgs picture for the high density phase transition in QCD$_2$ suggest that this transition is characterized by the spontaneous breaking of isospin for nuclear and quark matter.
[ { "created": "Tue, 20 Feb 2001 13:25:09 GMT", "version": "v1" }, { "created": "Mon, 5 May 2003 11:02:32 GMT", "version": "v2" } ]
2016-09-06
[ [ "Wetterich", "C.", "" ] ]
We explore the possibility that QCD may undergo a phase transition as a function of the strange quark mass. This would hint towards models with ``spontaneous color symmetry breaking'' in the vacuum. For two light quark flavors we classify possible colored quark-antiquark, diquark and gluon condensates that are compatible with a spectrum of integer charged states and conserved isospin and baryon number. The ``quark mass phase transition'' would be linked to an unusual realization of baryon number in QCD$_2$ and could be tested in lattice simulations. We emphasize, however, that at the present stage the Higgs picture of the vacuum cannot predict a quark mass phase transition - a smooth crossover remains as a realistic alternative. Implications of the Higgs picture for the high density phase transition in QCD$_2$ suggest that this transition is characterized by the spontaneous breaking of isospin for nuclear and quark matter.
1604.00335
Bj\"orn Schenke
Francois Gelis and Bjoern Schenke
Initial State Quantum Fluctuations in the Little Bang
17 pages, 9 figures, Manuscript accepted by Annual Reviews of Nuclear and Particle Science
null
10.1146/annurev-nucl-102115-044651
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We review recent developments in the ab-initio theoretical description of the initial state in heavy-ion collisions. We emphasize the importance of fluctuations, both for the phenomenological description of experimental data from the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), and the theoretical understanding of the non-equilibrium early time dynamics and thermalization of the medium.
[ { "created": "Fri, 1 Apr 2016 17:38:48 GMT", "version": "v1" } ]
2016-11-23
[ [ "Gelis", "Francois", "" ], [ "Schenke", "Bjoern", "" ] ]
We review recent developments in the ab-initio theoretical description of the initial state in heavy-ion collisions. We emphasize the importance of fluctuations, both for the phenomenological description of experimental data from the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), and the theoretical understanding of the non-equilibrium early time dynamics and thermalization of the medium.
hep-ph/9608258
Geoffrey B. West
Geoffrey B. West
The Glueball; The Fundamental Particle of Non-Perturbative QCD
14 pages. Talk given at the Montpelier Conference and Paris Workshop on QCD
null
null
null
hep-ph
null
Theoretical ideas related to the existence of glueballs in QCD are reviewed. These include non-perturbative phenomena such as confinement, instantons, vacuum condensates and renormalons. We also discuss glueball dominance of the trace of the stress-tensor, the mass content of the nucleon and a theorem on the lightest glueball state.
[ { "created": "Wed, 7 Aug 1996 20:46:54 GMT", "version": "v1" } ]
2007-05-23
[ [ "West", "Geoffrey B.", "" ] ]
Theoretical ideas related to the existence of glueballs in QCD are reviewed. These include non-perturbative phenomena such as confinement, instantons, vacuum condensates and renormalons. We also discuss glueball dominance of the trace of the stress-tensor, the mass content of the nucleon and a theorem on the lightest glueball state.
1108.0661
Juan Gonzalez-Fraile
O.J.P. Eboli, J. Gonzalez-Fraile and M.C. Gonzalez-Garcia
Neutrino Masses at LHC: Minimal Lepton Flavour Violation in Type-III See-saw
31 pages, 11 Figures, matches published version
null
10.1007/JHEP12(2011)009
YITP-SB-11-28 ICCUB-11-163
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the signatures of minimal lepton flavour violation in a simple Type-III see - saw model in which the flavour scale is given by the new fermion triplet mass and it can be naturally light enough to be produced at the LHC. In this model the flavour structure of the lepton number conserving couplings of the triplet fermions to the Standard Model leptons can be reconstructed from the neutrino mass matrix and the smallness of the neutrino mass is associated with a tiny violation of total lepton number. Characteristic signatures of this model include suppressed lepton number violation decays of the triplet fermions, absence of displaced vertices in their decays and predictable lepton flavour composition of the states produced in their decays. We study the observability of these signals in the processes $pp\rightarrow 3\ell + 2j +\Sla{E_T}$ and $pp\rightarrow 2\ell + 4j$ with $\ell =e$ or $\mu$ taking into account the present low energy data on neutrino physics and the corresponding Standard Model backgrounds. Our results indicate that the new fermionic states can be observed for masses up to 500 GeV depending on the CP violating Majorana phase for an integrated luminosity of 30 fb$^{-1}$. Moreover, the flavour of the final state leptons in the above processes can shed light on the neutrino mass ordering.
[ { "created": "Tue, 2 Aug 2011 20:00:00 GMT", "version": "v1" }, { "created": "Wed, 9 Nov 2011 11:18:35 GMT", "version": "v2" } ]
2015-05-30
[ [ "Eboli", "O. J. P.", "" ], [ "Gonzalez-Fraile", "J.", "" ], [ "Gonzalez-Garcia", "M. C.", "" ] ]
We study the signatures of minimal lepton flavour violation in a simple Type-III see - saw model in which the flavour scale is given by the new fermion triplet mass and it can be naturally light enough to be produced at the LHC. In this model the flavour structure of the lepton number conserving couplings of the triplet fermions to the Standard Model leptons can be reconstructed from the neutrino mass matrix and the smallness of the neutrino mass is associated with a tiny violation of total lepton number. Characteristic signatures of this model include suppressed lepton number violation decays of the triplet fermions, absence of displaced vertices in their decays and predictable lepton flavour composition of the states produced in their decays. We study the observability of these signals in the processes $pp\rightarrow 3\ell + 2j +\Sla{E_T}$ and $pp\rightarrow 2\ell + 4j$ with $\ell =e$ or $\mu$ taking into account the present low energy data on neutrino physics and the corresponding Standard Model backgrounds. Our results indicate that the new fermionic states can be observed for masses up to 500 GeV depending on the CP violating Majorana phase for an integrated luminosity of 30 fb$^{-1}$. Moreover, the flavour of the final state leptons in the above processes can shed light on the neutrino mass ordering.
1702.07288
G\"oran F\"aldt
G\"oran F\"aldt, Andrzej Kupsc
Hadronic structure functions in the $e^+ e^- \rightarrow \bar{\Lambda} \Lambda$ reaction
4 pages, 3 figures
null
10.1016/j.physletb.2017.06.011
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cross-section distributions are calculated for the reaction $e^+ e^- \rightarrow J/\psi\rightarrow \bar{\Lambda}(\rightarrow \bar{p}\pi^+) \Lambda(\rightarrow p\pi^-)$, and related annihilation reactions mediated by vector mesons. The hyperon-decay distributions depend on a number of structure functions that are bilinear in the, possibly complex, psionic form factors $G_M^\psi$ and $G_E^\psi$ of the Lambda hyperon. The relative size and relative phase of these form factors can be uniquely determined from the unpolarized joint-decay distributions of the Lambda and anti-Lambda hyperons. Also the decay-asymmetry parameters of Lambda and anti-Lambda hyperons can be determined.
[ { "created": "Thu, 23 Feb 2017 16:51:37 GMT", "version": "v1" }, { "created": "Mon, 15 May 2017 12:49:00 GMT", "version": "v2" } ]
2017-06-14
[ [ "Fäldt", "Göran", "" ], [ "Kupsc", "Andrzej", "" ] ]
Cross-section distributions are calculated for the reaction $e^+ e^- \rightarrow J/\psi\rightarrow \bar{\Lambda}(\rightarrow \bar{p}\pi^+) \Lambda(\rightarrow p\pi^-)$, and related annihilation reactions mediated by vector mesons. The hyperon-decay distributions depend on a number of structure functions that are bilinear in the, possibly complex, psionic form factors $G_M^\psi$ and $G_E^\psi$ of the Lambda hyperon. The relative size and relative phase of these form factors can be uniquely determined from the unpolarized joint-decay distributions of the Lambda and anti-Lambda hyperons. Also the decay-asymmetry parameters of Lambda and anti-Lambda hyperons can be determined.
0811.2728
Stefan Groote
S. Groote, J.G. K\"orner
Analytical results for O(\alpha_s) radiative corrections to e+ e- -> tbar t(pol.) up to a given gluon energy cut
49 pages in LaTeX, including 17 encapsulated PostScript figures
Physical Review D80(3) (2009) 034001
10.1103/PhysRevD.80.034001
MZ-TH/98-23
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We determine the O(\alpha_s) radiative corrections to polarized top quark pair production in e+ e- -annihilations with a specified gluon energy cut. We write down fully analytical results for the unpolarized and polarized O(\alpha_s) cross sections e+ e- -> tbar t (G) and e+ e- -> tbar t(pol.) (G) including their polar orientation dependence relative to the beam direction. In the soft gluon limit we recover the usual factorizing form known from the soft gluon approximation. In the limit when the gluon energy cut takes its maximum value we recover the totally inclusive unpolarized and polarized cross sections calculated previously. We provide some numerical results on the cut-off dependence of the various polarized and unpolarized cross sections and discuss how the exact results numerically differ from the approximate soft-gluon results.
[ { "created": "Mon, 17 Nov 2008 15:34:30 GMT", "version": "v1" }, { "created": "Wed, 5 Aug 2009 09:33:49 GMT", "version": "v2" } ]
2009-08-05
[ [ "Groote", "S.", "" ], [ "Körner", "J. G.", "" ] ]
We determine the O(\alpha_s) radiative corrections to polarized top quark pair production in e+ e- -annihilations with a specified gluon energy cut. We write down fully analytical results for the unpolarized and polarized O(\alpha_s) cross sections e+ e- -> tbar t (G) and e+ e- -> tbar t(pol.) (G) including their polar orientation dependence relative to the beam direction. In the soft gluon limit we recover the usual factorizing form known from the soft gluon approximation. In the limit when the gluon energy cut takes its maximum value we recover the totally inclusive unpolarized and polarized cross sections calculated previously. We provide some numerical results on the cut-off dependence of the various polarized and unpolarized cross sections and discuss how the exact results numerically differ from the approximate soft-gluon results.
hep-ph/9902405
B. Ananthanarayan
B. Ananthanarayan (Bangalore), and P. N. Pandita (Hamburg, Shillong)
Infra-red stable fixed points of R-parity violating Yukawa couplings in supersymmetric models
Plain latex to be run twice, 12 pages. Replaced with version to appear in Physics Letters B
Phys.Lett. B454 (1999) 84-91
10.1016/S0370-2693(99)00322-6
DESY 99-019, IISc-CTS-3/99
hep-ph
null
We investigate the infra-red stable fixed points of the Yukawa couplings in the minimal version of the supersymmetric standard model with R-parity violation. Retaining only the R-parity violating couplings of higher generations, we analytically study the solutions of the renormalization group equations of these couplings together with the top- and b-quark Yukawa couplings. We show that only the B-violating coupling $\lambda^{''}_{233}$ approaches a non-trivial infra-red stable fixed point, whereas all other non-trivial fixed point solutions are either unphysical or unstable in the infra-red region. However, this fixed point solution predicts a top-quark Yukawa coupling which is incompatible with the top quark mass for any value of $\tan\beta$.
[ { "created": "Fri, 19 Feb 1999 16:13:54 GMT", "version": "v1" }, { "created": "Mon, 22 Feb 1999 03:56:14 GMT", "version": "v2" }, { "created": "Tue, 30 Mar 1999 09:32:08 GMT", "version": "v3" } ]
2009-10-31
[ [ "Ananthanarayan", "B.", "", "Bangalore" ], [ "Pandita", "P. N.", "", "Hamburg, Shillong" ] ]
We investigate the infra-red stable fixed points of the Yukawa couplings in the minimal version of the supersymmetric standard model with R-parity violation. Retaining only the R-parity violating couplings of higher generations, we analytically study the solutions of the renormalization group equations of these couplings together with the top- and b-quark Yukawa couplings. We show that only the B-violating coupling $\lambda^{''}_{233}$ approaches a non-trivial infra-red stable fixed point, whereas all other non-trivial fixed point solutions are either unphysical or unstable in the infra-red region. However, this fixed point solution predicts a top-quark Yukawa coupling which is incompatible with the top quark mass for any value of $\tan\beta$.
hep-ph/9702362
Robert D. Pisarski
Robert D. Pisarski, T.L. Trueman and Michel H.G. Tytgat
How pi0 -> gamma gamma changes with temperature
12 pages, ReVTeX, 4 figures, to be published in Phys. Rev. D. New section 5 with proof of the Adler-Bardeen theorem at low T
Phys.Rev.D56:7077-7088,1997
10.1103/PhysRevD.56.7077
null
hep-ph nucl-th
null
At zero temperature, in the chiral limit the amplitude for pi0 to decay into two photons is directly related to the coefficient of the axial anomaly. At any nonzero temperature, this direct relationship is lost: while the coefficient of the axial anomaly is independent of temperature, in a thermal bath the anomalous Ward identities do not uniquely constrain the amplitude for pi0 -> gamma gamma. Explicit calculation shows that to lowest order about zero temperature, this amplitude decreases.
[ { "created": "Tue, 18 Feb 1997 19:12:25 GMT", "version": "v1" }, { "created": "Wed, 23 Jul 1997 18:52:08 GMT", "version": "v2" } ]
2014-11-17
[ [ "Pisarski", "Robert D.", "" ], [ "Trueman", "T. L.", "" ], [ "Tytgat", "Michel H. G.", "" ] ]
At zero temperature, in the chiral limit the amplitude for pi0 to decay into two photons is directly related to the coefficient of the axial anomaly. At any nonzero temperature, this direct relationship is lost: while the coefficient of the axial anomaly is independent of temperature, in a thermal bath the anomalous Ward identities do not uniquely constrain the amplitude for pi0 -> gamma gamma. Explicit calculation shows that to lowest order about zero temperature, this amplitude decreases.
hep-ph/9904356
Borisov
A.V.Borisov and P.E.Sizin
Propagation of axions in a strongly magnetized medium
RevTex, no figures, 13 pages, Revised version of the paper published in J. Exp. Theor. Phys. {\bf 88}, 1 (1999)
J.Exp.Theor.Phys. 88 (1999) 1-5; Zh.Eksp.Teor.Fiz. 115 (1999) 3-11
10.1134/1.558755
null
hep-ph
null
The polarization operator of an axion in a degenerate gas of electrons occupying the ground-state Landau level in a superstrong magnetic field $H\gg H_0=m_e^2c^3/e\hbar =4.41\cdot 10^{13}$ G is investigated in a model with a tree-level axion-electron coupling. It is shown that a dynamic axion mass, which can fall within the allowed range of values $(10^{-5} eV \lesssim m_a\lesssim 10^{-2} eV)$, is generated under the conditions of strongly magnetized neutron stars. As a result, the dispersion relation for axions is appreciably different from that in a vacuum.
[ { "created": "Fri, 16 Apr 1999 07:31:52 GMT", "version": "v1" } ]
2009-10-31
[ [ "Borisov", "A. V.", "" ], [ "Sizin", "P. E.", "" ] ]
The polarization operator of an axion in a degenerate gas of electrons occupying the ground-state Landau level in a superstrong magnetic field $H\gg H_0=m_e^2c^3/e\hbar =4.41\cdot 10^{13}$ G is investigated in a model with a tree-level axion-electron coupling. It is shown that a dynamic axion mass, which can fall within the allowed range of values $(10^{-5} eV \lesssim m_a\lesssim 10^{-2} eV)$, is generated under the conditions of strongly magnetized neutron stars. As a result, the dispersion relation for axions is appreciably different from that in a vacuum.
0904.2213
Pavel Fileviez Perez
Pavel Fileviez Perez, Sogee Spinner
Spontaneous R-Parity Breaking in SUSY Models
9 pages, typos corrected, to appear in Physical Review D
Phys.Rev.D80:015004,2009
10.1103/PhysRevD.80.015004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate a mechanism for spontaneous R-parity breaking in a class of extensions of the minimal supersymmetric standard model with an extra Abelian gauge symmetry which is a linear combination of B-L and weak hypercharge. Both U(1)_X and R-parity are broken by the vacuum expectation value of the right-handed sneutrinos which is proportional to the soft SUSY masses. In these models the mechanism for spontaneous R-parity violation can be realized even with positive soft masses. In this context one has a realistic mechanism for generating neutrino masses as well as a realistic spectrum. We briefly discuss the possible collider signals which could be used to test the theory, the contributions for proton decay and the possibility of a gravitino as a dark matter candidate.
[ { "created": "Tue, 14 Apr 2009 22:10:26 GMT", "version": "v1" }, { "created": "Tue, 23 Jun 2009 16:02:24 GMT", "version": "v2" } ]
2009-07-10
[ [ "Perez", "Pavel Fileviez", "" ], [ "Spinner", "Sogee", "" ] ]
We investigate a mechanism for spontaneous R-parity breaking in a class of extensions of the minimal supersymmetric standard model with an extra Abelian gauge symmetry which is a linear combination of B-L and weak hypercharge. Both U(1)_X and R-parity are broken by the vacuum expectation value of the right-handed sneutrinos which is proportional to the soft SUSY masses. In these models the mechanism for spontaneous R-parity violation can be realized even with positive soft masses. In this context one has a realistic mechanism for generating neutrino masses as well as a realistic spectrum. We briefly discuss the possible collider signals which could be used to test the theory, the contributions for proton decay and the possibility of a gravitino as a dark matter candidate.
hep-ph/0512340
Jiri Chyla
Jiri Chyla
On higher order corrections to photon structure functions
14 pages, 2 eps figures, couple of typos and misprints corrected
null
null
null
hep-ph
null
The QCD corrections to photon structure functions are defined in a way consistent with the factorization scheme invariance. It is shown that the conventional DIS$_{\gamma}$ factorization scheme does not respect this invariance and is thus deeply flawed. The origins of the divergent behavior of photonic coefficient function at large $x$ are analyzed and recipe to remove it is suggested.
[ { "created": "Tue, 27 Dec 2005 15:36:07 GMT", "version": "v1" }, { "created": "Tue, 3 Jan 2006 13:01:30 GMT", "version": "v2" } ]
2007-05-23
[ [ "Chyla", "Jiri", "" ] ]
The QCD corrections to photon structure functions are defined in a way consistent with the factorization scheme invariance. It is shown that the conventional DIS$_{\gamma}$ factorization scheme does not respect this invariance and is thus deeply flawed. The origins of the divergent behavior of photonic coefficient function at large $x$ are analyzed and recipe to remove it is suggested.
1011.6470
Alfredo Aranda
Alfredo Aranda, Cesar Bonilla, Raymundo Ramos, Alma D. Rojas
A renormalizable fermion mass model with the double tetrahedral group
14 pages, 2 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a renormalizable model for fermion masses based solely on the double tetrahedral group T'. It does not include right handed neutrinos and majorana neutrino masses are generated radiatively. The scalar sector of the model involves three SU(2) doublets and a set of lepton number violating (charged) scalars needed to give mass to the neutrinos. In the quark sector the model leads to a Fritzsch type scenario that is consistent with all the existing data. In the lepton sector, the model leads to tribimaximal (and near tribimaximal) mixing, and an inverted mass hierarchy.
[ { "created": "Tue, 30 Nov 2010 06:59:12 GMT", "version": "v1" } ]
2010-12-01
[ [ "Aranda", "Alfredo", "" ], [ "Bonilla", "Cesar", "" ], [ "Ramos", "Raymundo", "" ], [ "Rojas", "Alma D.", "" ] ]
We present a renormalizable model for fermion masses based solely on the double tetrahedral group T'. It does not include right handed neutrinos and majorana neutrino masses are generated radiatively. The scalar sector of the model involves three SU(2) doublets and a set of lepton number violating (charged) scalars needed to give mass to the neutrinos. In the quark sector the model leads to a Fritzsch type scenario that is consistent with all the existing data. In the lepton sector, the model leads to tribimaximal (and near tribimaximal) mixing, and an inverted mass hierarchy.
hep-ph/0612314
Carlos Luis Schat
Dan Pirjol and Carlos Schat
Positive parity pentaquark towers in large Nc QCD
21 pages, 2 figures, 5 tables
Phys.Rev.D75:076004,2007
10.1103/PhysRevD.75.076004
null
hep-ph
null
We construct the complete set of positive parity pentaquarks, which correspond in the quark model to {\bar s} q^{Nc+1} states with one unit of orbital angular momentum L=1. In the large Nc limit they fall into the K=1/2 and K=3/2 irreps (towers) of the contracted SU(4)c symmetry. We derive predictions for the mass spectrum and the axial couplings of these states at leading order in 1/Nc. The strong decay width of the lowest-lying positive parity exotic state is of order O(1/Nc), such that this state is narrow in the large Nc limit. Replacing the antiquark with a heavy antiquark {\bar Q} q^{Nc+1}, the two towers become degenerate, split only by O(1/mQ) hyperfine interactions. We obtain predictions for the strong decay widths of heavy pentaquarks to ordinary baryons and heavy H(*)_{\bar Q} mesons at leading order in 1/Nc and 1/mQ.
[ { "created": "Fri, 22 Dec 2006 20:04:30 GMT", "version": "v1" } ]
2008-11-26
[ [ "Pirjol", "Dan", "" ], [ "Schat", "Carlos", "" ] ]
We construct the complete set of positive parity pentaquarks, which correspond in the quark model to {\bar s} q^{Nc+1} states with one unit of orbital angular momentum L=1. In the large Nc limit they fall into the K=1/2 and K=3/2 irreps (towers) of the contracted SU(4)c symmetry. We derive predictions for the mass spectrum and the axial couplings of these states at leading order in 1/Nc. The strong decay width of the lowest-lying positive parity exotic state is of order O(1/Nc), such that this state is narrow in the large Nc limit. Replacing the antiquark with a heavy antiquark {\bar Q} q^{Nc+1}, the two towers become degenerate, split only by O(1/mQ) hyperfine interactions. We obtain predictions for the strong decay widths of heavy pentaquarks to ordinary baryons and heavy H(*)_{\bar Q} mesons at leading order in 1/Nc and 1/mQ.
hep-ph/9709512
null
John McDonald
Spontaneous Discrete Symmetry Breaking During Inflation and the NMSSM Domain Wall Problem
LaTex, 30 pages, revised version
Nucl.Phys. B530 (1998) 325-345
10.1016/S0550-3213(98)00414-3
null
hep-ph
null
The Next to Minimal Supersymmetric Standard Model (NMSSM), proposed as a solution of the mu problem of the Minimal Supersymmetric Standard Model, has a discrete Z_{3} symmetry which is spontaneously broken at the electroweak phase transition, resulting in a cosmological domain wall problem. In most cases this domain wall problem cannot be solved by explicit Z_{3} breaking without introducing supergravity tadpole corrections which destabilize the weak scale hierarchy. Here we consider the possibility of solving the domain wall problem of the NMSSM via spontaneous discrete symmetry breaking occuring during inflation. For the case where the discrete symmetry breaking field has renormalizible couplings to the NMSSM fields, we find that the couplings must be less than 10^{-5} if the reheating temperature is larger than 10^{7}GeV, but can be up to 10^{-3} for reheating temperatures of the order of the electroweak phase transition temperature. For the case of non-renormalizible couplings, we present a model which can solve the domain wall problem for large reheating temperatures without requiring any very small coupling constants. In this model the domain walls are eliminated by a pressure coming from their interaction with a coherently oscillating scalar field whose phase is fixed during inflation. This oscillating scalar field typically decays after the electroweak phase transition but before nucleosynthesis, leaving no additional Z_{3} symmetry breaking in the zero-temperature theory.
[ { "created": "Tue, 30 Sep 1997 19:22:45 GMT", "version": "v1" }, { "created": "Wed, 8 Oct 1997 13:04:48 GMT", "version": "v2" }, { "created": "Thu, 2 Apr 1998 09:50:25 GMT", "version": "v3" } ]
2016-09-06
[ [ "McDonald", "John", "" ] ]
The Next to Minimal Supersymmetric Standard Model (NMSSM), proposed as a solution of the mu problem of the Minimal Supersymmetric Standard Model, has a discrete Z_{3} symmetry which is spontaneously broken at the electroweak phase transition, resulting in a cosmological domain wall problem. In most cases this domain wall problem cannot be solved by explicit Z_{3} breaking without introducing supergravity tadpole corrections which destabilize the weak scale hierarchy. Here we consider the possibility of solving the domain wall problem of the NMSSM via spontaneous discrete symmetry breaking occuring during inflation. For the case where the discrete symmetry breaking field has renormalizible couplings to the NMSSM fields, we find that the couplings must be less than 10^{-5} if the reheating temperature is larger than 10^{7}GeV, but can be up to 10^{-3} for reheating temperatures of the order of the electroweak phase transition temperature. For the case of non-renormalizible couplings, we present a model which can solve the domain wall problem for large reheating temperatures without requiring any very small coupling constants. In this model the domain walls are eliminated by a pressure coming from their interaction with a coherently oscillating scalar field whose phase is fixed during inflation. This oscillating scalar field typically decays after the electroweak phase transition but before nucleosynthesis, leaving no additional Z_{3} symmetry breaking in the zero-temperature theory.
1412.1485
Wei Xue
Jia Liu, Neal Weiner and Wei Xue
Signals of a Light Dark Force in the Galactic Center
39 pages, 14 figures, references updated and discussion of CMB constraints included
JHEP 08 (2015) 050
10.1007/JHEP08(2015)050
MIT-CTP/4616, MITP/14-100
hep-ph astro-ph.GA astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent evidence for an excess of gamma rays in the GeV energy range about the Galactic Center have refocused attention on models of dark matter in the low mass regime ($m_\chi \lesssim m_Z/2$). Because this is an experimentally well-trod energy range, it can be a challenge to develop simple models that explain this excess, consistent with other experimental constraints. We reconsider models where the dark matter couples to dark photon, which has a weak kinetic mixing to the Standard Model photon, or scalars with a weak mixing with the Higgs boson. We focus on the light ($\lesssim 1.5 GeV$) dark mediator mass regime. Annihilations into the dark mediators can produce observable gamma rays through decays to $\pi^0$, through radiative processes when decaying to charged particles ($e^+e^-, \mu^+\mu^-,...$), and subsequent interactions of high energy $e^+e^-$ with gas and light. However, these models have no signals of $\bar p$ production, which is kinematically forbidden. We find that in these models, the shape of resulting gamma-ray spectrum can provide a good fit to the excess at Galactic Center. We discuss further constraints from AMS-02, and find regions of compatibility.
[ { "created": "Wed, 3 Dec 2014 21:03:16 GMT", "version": "v1" }, { "created": "Tue, 30 Jun 2015 23:24:59 GMT", "version": "v2" } ]
2015-08-21
[ [ "Liu", "Jia", "" ], [ "Weiner", "Neal", "" ], [ "Xue", "Wei", "" ] ]
Recent evidence for an excess of gamma rays in the GeV energy range about the Galactic Center have refocused attention on models of dark matter in the low mass regime ($m_\chi \lesssim m_Z/2$). Because this is an experimentally well-trod energy range, it can be a challenge to develop simple models that explain this excess, consistent with other experimental constraints. We reconsider models where the dark matter couples to dark photon, which has a weak kinetic mixing to the Standard Model photon, or scalars with a weak mixing with the Higgs boson. We focus on the light ($\lesssim 1.5 GeV$) dark mediator mass regime. Annihilations into the dark mediators can produce observable gamma rays through decays to $\pi^0$, through radiative processes when decaying to charged particles ($e^+e^-, \mu^+\mu^-,...$), and subsequent interactions of high energy $e^+e^-$ with gas and light. However, these models have no signals of $\bar p$ production, which is kinematically forbidden. We find that in these models, the shape of resulting gamma-ray spectrum can provide a good fit to the excess at Galactic Center. We discuss further constraints from AMS-02, and find regions of compatibility.
2006.11217
William J. Torres Bobadilla Dr.
J. Jesus Aguilera-Verdugo, Roger J. Hernandez-Pinto, German Rodrigo, German F. R. Sborlini, William J. Torres Bobadilla
Causal representation of multi-loop Feynman integrands within the loop-tree duality
24 pages, 8 figures. v2: references added; matches published version
null
10.1007/JHEP01(2021)069
IFIC/20-27
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
The numerical evaluation of multi-loop scattering amplitudes in the Feynman representation usually requires to deal with both physical (causal) and unphysical (non-causal) singularities. The loop-tree duality (LTD) offers a powerful framework to easily characterise and distinguish these two types of singularities, and then simplify analytically the underling expressions. In this paper, we work explicitly on the dual representation of multi-loop Feynman integrals generated from three parent topologies, which we refer to as Maximal, Next-to-Maximal and Next-to-Next-to-Maximal loop topologies. In particular, we aim at expressing these dual contributions, independently of the number of loops and internal configurations, in terms of causal propagators only. Thus, providing very compact and causal integrand representations to all orders. In order to do so, we reconstruct their analytic expressions from numerical evaluation over finite fields. This procedure implicitly cancels out all unphysical singularities. We also interpret the result in terms of entangled causal thresholds. In view of the simple structure of the dual expressions, we integrate them numerically up to four loops in integer space-time dimensions, taking advantage of their smooth behaviour at integrand level.
[ { "created": "Fri, 19 Jun 2020 16:42:36 GMT", "version": "v1" }, { "created": "Tue, 22 Jun 2021 16:08:33 GMT", "version": "v2" } ]
2021-06-23
[ [ "Aguilera-Verdugo", "J. Jesus", "" ], [ "Hernandez-Pinto", "Roger J.", "" ], [ "Rodrigo", "German", "" ], [ "Sborlini", "German F. R.", "" ], [ "Bobadilla", "William J. Torres", "" ] ]
The numerical evaluation of multi-loop scattering amplitudes in the Feynman representation usually requires to deal with both physical (causal) and unphysical (non-causal) singularities. The loop-tree duality (LTD) offers a powerful framework to easily characterise and distinguish these two types of singularities, and then simplify analytically the underling expressions. In this paper, we work explicitly on the dual representation of multi-loop Feynman integrals generated from three parent topologies, which we refer to as Maximal, Next-to-Maximal and Next-to-Next-to-Maximal loop topologies. In particular, we aim at expressing these dual contributions, independently of the number of loops and internal configurations, in terms of causal propagators only. Thus, providing very compact and causal integrand representations to all orders. In order to do so, we reconstruct their analytic expressions from numerical evaluation over finite fields. This procedure implicitly cancels out all unphysical singularities. We also interpret the result in terms of entangled causal thresholds. In view of the simple structure of the dual expressions, we integrate them numerically up to four loops in integer space-time dimensions, taking advantage of their smooth behaviour at integrand level.
2204.12542
Jo\~ao Pedro Pino Gon\c{c}alves
Felipe F. Freitas and Jo\~ao Gon\c{c}alves and Ant\'onio P. Morais and Roman Pasechnik
Phenomenology at the Large Hadron Collider with Deep Learning: the case of vector-like quarks decaying to light jets
24 pages, 4 tables and 8 figures. Matches version to be published in EPJC
null
10.1140/epjc/s10052-022-10799-8
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this work, we continue our exploration of TeV-scale vector-like fermion signatures inspired by a Grand Unification scenario based on the trinification gauge group. A particular focus is given to pair-production topologies of vector-like quarks (VLQs) at the LHC, in a multi-jet plus a charged lepton and a missing energy signature. We employ Deep Learning methods and techniques based in evolutive algorithms that optimize hyper-parameters in the neural network construction, whose objective is to maximise the Asimov estimate for distinct VLQ masses. In this article, we consider the implications of an innovative approach by simultaneously combining detector images (also known as jet images) and tabular data containing kinematic information from the final states. With this technique we are able to exclude VLQs, that are specific for the considered model, to up a mass of 800 GeV in both the high-luminosity the Run-III phases of the LHC programme.
[ { "created": "Tue, 26 Apr 2022 18:50:02 GMT", "version": "v1" }, { "created": "Thu, 11 Aug 2022 13:56:16 GMT", "version": "v2" }, { "created": "Mon, 12 Sep 2022 08:15:22 GMT", "version": "v3" } ]
2022-09-28
[ [ "Freitas", "Felipe F.", "" ], [ "Gonçalves", "João", "" ], [ "Morais", "António P.", "" ], [ "Pasechnik", "Roman", "" ] ]
In this work, we continue our exploration of TeV-scale vector-like fermion signatures inspired by a Grand Unification scenario based on the trinification gauge group. A particular focus is given to pair-production topologies of vector-like quarks (VLQs) at the LHC, in a multi-jet plus a charged lepton and a missing energy signature. We employ Deep Learning methods and techniques based in evolutive algorithms that optimize hyper-parameters in the neural network construction, whose objective is to maximise the Asimov estimate for distinct VLQ masses. In this article, we consider the implications of an innovative approach by simultaneously combining detector images (also known as jet images) and tabular data containing kinematic information from the final states. With this technique we are able to exclude VLQs, that are specific for the considered model, to up a mass of 800 GeV in both the high-luminosity the Run-III phases of the LHC programme.
2011.08053
Amin Aboubrahim
Amin Aboubrahim, Michael Klasen, and Pran Nath
Xenon-1T excess as a possible signal of a sub-GeV hidden sector dark matter
21 pages, 4 figures, 1 table. Accepted for publication in JHEP
null
10.1007/JHEP02(2021)229
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We present a particle physics model to explain the observed enhancement in the Xenon-1T data at an electron recoil energy of 2.5 keV. The model is based on a $U(1)$ extension of the Standard Model where the dark sector consists of two essentially mass degenerate Dirac fermions in the sub-GeV region with a small mass splitting interacting with a dark photon. The dark photon is unstable and decays before the big bang nucleosynthesis, which leads to the dark matter constituted of two essentially mass degenerate Dirac fermions. The Xenon-1T excess is computed via the inelastic exothermic scattering of the heavier dark fermion from a bound electron in xenon to the lighter dark fermion producing the observed excess events in the recoil electron energy. The model can be tested with further data from Xenon-1T and in future experiments such as SuperCDMS.
[ { "created": "Mon, 16 Nov 2020 16:06:48 GMT", "version": "v1" }, { "created": "Mon, 25 Jan 2021 20:40:46 GMT", "version": "v2" } ]
2021-03-17
[ [ "Aboubrahim", "Amin", "" ], [ "Klasen", "Michael", "" ], [ "Nath", "Pran", "" ] ]
We present a particle physics model to explain the observed enhancement in the Xenon-1T data at an electron recoil energy of 2.5 keV. The model is based on a $U(1)$ extension of the Standard Model where the dark sector consists of two essentially mass degenerate Dirac fermions in the sub-GeV region with a small mass splitting interacting with a dark photon. The dark photon is unstable and decays before the big bang nucleosynthesis, which leads to the dark matter constituted of two essentially mass degenerate Dirac fermions. The Xenon-1T excess is computed via the inelastic exothermic scattering of the heavier dark fermion from a bound electron in xenon to the lighter dark fermion producing the observed excess events in the recoil electron energy. The model can be tested with further data from Xenon-1T and in future experiments such as SuperCDMS.
1610.08549
Zhongwen Feng
Zhong-Wen Feng, Shu-Zheng Yang, Hui-Ling Li, Xiao-Tao Zu
Constraining the generalized uncertainty principle with the gravitational wave event GW150914
8 pages, 2 Tables
Physics Letters B 768 (2017) 81-85
10.1016/j.physletb.2017.02.043
null
hep-ph gr-qc hep-th
http://creativecommons.org/licenses/by/4.0/
In this letter, we show that the dimensionless parameter in the generalized uncertainty principle (GUP) can be constrained by the gravitational wave event GW150914, which was discovered by the LIGO Scientific and Virgo Collaborations. Firstly, according to the Heisenberg uncertainty principle (HUP) and the data of gravitational wave event GW150914, we derive the standard energy-momentum dispersion relation and calculate the difference between the propagation speed of gravitons and the speed of light, i.e., $\Delta \upsilon$. Next, using two proposals regarding the GUP, we also generalize our study to the quantum gravity case and obtain the modified speed of gravitons. Finally, based on the modified speed of gravitons and $\Delta \upsilon$, the improved upper bounds on the GUP parameters are obtained. The results show that the upper limits of the GUP parameters $\beta_0$ and $\alpha_0$ are $2.3 \times 10^ {60}$ and $1.8 \times 10^{20}$.
[ { "created": "Sat, 22 Oct 2016 10:08:14 GMT", "version": "v1" }, { "created": "Wed, 9 Nov 2016 13:01:05 GMT", "version": "v2" }, { "created": "Fri, 17 Feb 2017 03:25:06 GMT", "version": "v3" }, { "created": "Fri, 3 Mar 2017 07:07:02 GMT", "version": "v4" } ]
2017-03-06
[ [ "Feng", "Zhong-Wen", "" ], [ "Yang", "Shu-Zheng", "" ], [ "Li", "Hui-Ling", "" ], [ "Zu", "Xiao-Tao", "" ] ]
In this letter, we show that the dimensionless parameter in the generalized uncertainty principle (GUP) can be constrained by the gravitational wave event GW150914, which was discovered by the LIGO Scientific and Virgo Collaborations. Firstly, according to the Heisenberg uncertainty principle (HUP) and the data of gravitational wave event GW150914, we derive the standard energy-momentum dispersion relation and calculate the difference between the propagation speed of gravitons and the speed of light, i.e., $\Delta \upsilon$. Next, using two proposals regarding the GUP, we also generalize our study to the quantum gravity case and obtain the modified speed of gravitons. Finally, based on the modified speed of gravitons and $\Delta \upsilon$, the improved upper bounds on the GUP parameters are obtained. The results show that the upper limits of the GUP parameters $\beta_0$ and $\alpha_0$ are $2.3 \times 10^ {60}$ and $1.8 \times 10^{20}$.
0903.4978
Joan Sola
Nicolas Bernal, David Lopez-Val, Joan Sola
Single Higgs-boson production through gamma-gamma scattering within the general 2HDM
References and comments added. Accepted in Phys. Lett. B
Phys.Lett.B677:39-47,2009
10.1016/j.physletb.2009.05.013
UB-ECM-PF-09/06
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The production of a single neutral Higgs boson h through (loop-induced) gamma-gamma collisions is explored in the context of the linear colliders within the general Two-Higgs-Doublet Model (2HDM). Two different mechanisms are analyzed: on the one hand, the scattering gamma gamma-> h of two real photons in a gamma-gamma collider; on the other, the more traditional mechanism of virtual photon fusion, e+e- -->e+e- + h. Owing to the peculiar properties of the Higgs boson self-interactions within the general 2HDM, we find that the overall production rates can be boosted up significantly, provided the charged Higgs mass is not too heavy. For example, if the latter is slightly above 100 GeV and, in addition, the lightest CP-even Higgs boson falls in the ballpark of the LEP bound on the SM Higgs mass up to a few hundred GeV, the cross-sections may typically render \sigma(gamma gamma-> h)= 0.1-1 pb and \sigma(e+e- --> e+e- + h)\sim 0.01 pb -- in both cases well above the SM prediction. Although for charged Higgs masses above 300 GeV the rates become virtually insensitive to the Higgs boson self-couplings, a significant tail of non-SM effects produced by the combined contribution of the Yukawa couplings and gauge bosons could still reveal a smoking gun.
[ { "created": "Sat, 28 Mar 2009 17:44:07 GMT", "version": "v1" }, { "created": "Thu, 2 Apr 2009 19:40:42 GMT", "version": "v2" }, { "created": "Thu, 7 May 2009 07:02:20 GMT", "version": "v3" } ]
2014-11-18
[ [ "Bernal", "Nicolas", "" ], [ "Lopez-Val", "David", "" ], [ "Sola", "Joan", "" ] ]
The production of a single neutral Higgs boson h through (loop-induced) gamma-gamma collisions is explored in the context of the linear colliders within the general Two-Higgs-Doublet Model (2HDM). Two different mechanisms are analyzed: on the one hand, the scattering gamma gamma-> h of two real photons in a gamma-gamma collider; on the other, the more traditional mechanism of virtual photon fusion, e+e- -->e+e- + h. Owing to the peculiar properties of the Higgs boson self-interactions within the general 2HDM, we find that the overall production rates can be boosted up significantly, provided the charged Higgs mass is not too heavy. For example, if the latter is slightly above 100 GeV and, in addition, the lightest CP-even Higgs boson falls in the ballpark of the LEP bound on the SM Higgs mass up to a few hundred GeV, the cross-sections may typically render \sigma(gamma gamma-> h)= 0.1-1 pb and \sigma(e+e- --> e+e- + h)\sim 0.01 pb -- in both cases well above the SM prediction. Although for charged Higgs masses above 300 GeV the rates become virtually insensitive to the Higgs boson self-couplings, a significant tail of non-SM effects produced by the combined contribution of the Yukawa couplings and gauge bosons could still reveal a smoking gun.
2102.03050
Zhi-zhong Xing
Zhi-zhong Xing
A translational flavor symmetry in the mass terms of Dirac and Majorana fermions
15 pages. A proof is given to show that the translation of a massless neutrino field, which assures the Dirac equation to be invariant, is equivalent to the translational transformations of three neutrino flavor states in the flavor space as a consequence of flavor mixing. More discussions are added. Accepted for publication in JPG
null
10.1088/1361-6471/ac421e
null
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
Requiring the effective mass term for a category of fundamental Dirac or Majorana fermions of the same electric charge to be invariant under the translational transformations $\psi^{}_{\alpha \rm L (R)} \to \psi^{}_{\alpha \rm L (R)} + n^{}_{\alpha} z^{}_{\psi \rm L(R)}$ in the flavor space, where $n^{}_\alpha$ and $z^{}_{\psi \rm L(R)}$ stand respectively for the flavor-dependent complex numbers and a constant spinor field anticommuting with the fermion fields, we show that $n^{}_\alpha$ can be identified as the elements $U^{}_{\alpha i}$ in the $i$-th column of the unitary matrix $U$ used to diagonalize the corresponding Hermitian or symmetric fermion mass matrix $M^{}_\psi$, and $m^{}_i = 0$ holds accordingly. We find that the reverse is also true. Now that the mass spectra of charged leptons, up- and down-type quarks are all strongly hierarchical and current experimental data allow the lightest neutrino to be massless, we argue that the zero mass limit for the first-family fermions and the translational flavor symmetry behind it should be a natural starting point for building viable fermion mass models.
[ { "created": "Fri, 5 Feb 2021 08:24:28 GMT", "version": "v1" }, { "created": "Sat, 11 Dec 2021 08:29:18 GMT", "version": "v2" } ]
2022-01-19
[ [ "Xing", "Zhi-zhong", "" ] ]
Requiring the effective mass term for a category of fundamental Dirac or Majorana fermions of the same electric charge to be invariant under the translational transformations $\psi^{}_{\alpha \rm L (R)} \to \psi^{}_{\alpha \rm L (R)} + n^{}_{\alpha} z^{}_{\psi \rm L(R)}$ in the flavor space, where $n^{}_\alpha$ and $z^{}_{\psi \rm L(R)}$ stand respectively for the flavor-dependent complex numbers and a constant spinor field anticommuting with the fermion fields, we show that $n^{}_\alpha$ can be identified as the elements $U^{}_{\alpha i}$ in the $i$-th column of the unitary matrix $U$ used to diagonalize the corresponding Hermitian or symmetric fermion mass matrix $M^{}_\psi$, and $m^{}_i = 0$ holds accordingly. We find that the reverse is also true. Now that the mass spectra of charged leptons, up- and down-type quarks are all strongly hierarchical and current experimental data allow the lightest neutrino to be massless, we argue that the zero mass limit for the first-family fermions and the translational flavor symmetry behind it should be a natural starting point for building viable fermion mass models.
hep-ph/9608330
Gregory Gabadadze
Glennys R. Farrar and G.T. Gabadadze (Rutgers Univ.)
Light Gluino Mass and Condensate from Properties of $\eta$ and $\eta'$
14 pages, LATEX file, 1 PS fig. Some discussions are added, to be published in Phys. Lett. B
Phys.Lett. B397 (1997) 104-111
10.1016/S0370-2693(97)00151-2
null
hep-ph
null
We investigate whether known properties of the $\eta'$ meson are consistent with its being the Goldstone boson of the spontaneously broken anomaly-free R symmetry required in the light gluino scenario. We fit the masses and $2\gamma$ decays of the $\eta$ and $\eta'$ mesons, and also their production in radiative $J/\psi$ decays. We find that the $\eta-\eta'$ system is well-described in the light gluino scenario, if $m_\lambda\simeq (84-144) MeV$ and $<{\bar\lambda}\lambda> \simeq -(0.15-0.36) GeV^3$. These values are in the range expected when the gluino gets its mass entirely from radiative corrections.
[ { "created": "Thu, 15 Aug 1996 02:07:13 GMT", "version": "v1" }, { "created": "Fri, 7 Feb 1997 22:09:01 GMT", "version": "v2" } ]
2009-10-28
[ [ "Farrar", "Glennys R.", "", "Rutgers Univ." ], [ "Gabadadze", "G. T.", "", "Rutgers Univ." ] ]
We investigate whether known properties of the $\eta'$ meson are consistent with its being the Goldstone boson of the spontaneously broken anomaly-free R symmetry required in the light gluino scenario. We fit the masses and $2\gamma$ decays of the $\eta$ and $\eta'$ mesons, and also their production in radiative $J/\psi$ decays. We find that the $\eta-\eta'$ system is well-described in the light gluino scenario, if $m_\lambda\simeq (84-144) MeV$ and $<{\bar\lambda}\lambda> \simeq -(0.15-0.36) GeV^3$. These values are in the range expected when the gluino gets its mass entirely from radiative corrections.
2207.07737
Tom Steudtner
Gudrun Hiller, Tim H\"ohne, Daniel F. Litim, Tom Steudtner
Portals into Higgs vacuum stability
18 pages, 16 figures. v2: match published version
null
10.1103/PhysRevD.106.115004
DO-TH 21/08
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address the notorious metastability of the standard model (SM) and promote it to a model building task: What are the new ingredients required to stabilize the SM up to the Planck scale without encountering subplanckian Landau poles? Using the SM extended by vector-like fermions (VLFs), we chart out the corresponding landscape of Higgs stability. We find that the gauge portal mechanism, triggered by new SM charge carriers, opens up sizeable room for stability in a minimally invasive manner. We also find models with Higgs criticality, and Yukawa portals opening up at stronger coupling. Several models allow for VLFs in the TeV-range, which can be searched for at the LHC. For nontrivial flavor structure severe flavor-changing neutral current constraints arise which complement those from stability, and push lower fermion masses up to $\mathcal{O}(10^3\,\text{TeV})$.
[ { "created": "Fri, 15 Jul 2022 20:22:35 GMT", "version": "v1" }, { "created": "Wed, 30 Nov 2022 20:02:39 GMT", "version": "v2" } ]
2022-12-14
[ [ "Hiller", "Gudrun", "" ], [ "Höhne", "Tim", "" ], [ "Litim", "Daniel F.", "" ], [ "Steudtner", "Tom", "" ] ]
We address the notorious metastability of the standard model (SM) and promote it to a model building task: What are the new ingredients required to stabilize the SM up to the Planck scale without encountering subplanckian Landau poles? Using the SM extended by vector-like fermions (VLFs), we chart out the corresponding landscape of Higgs stability. We find that the gauge portal mechanism, triggered by new SM charge carriers, opens up sizeable room for stability in a minimally invasive manner. We also find models with Higgs criticality, and Yukawa portals opening up at stronger coupling. Several models allow for VLFs in the TeV-range, which can be searched for at the LHC. For nontrivial flavor structure severe flavor-changing neutral current constraints arise which complement those from stability, and push lower fermion masses up to $\mathcal{O}(10^3\,\text{TeV})$.
2211.08838
Melih Arslan Ozcelik
Samuel Abreu, Matteo Becchetti, Claude Duhr, Melih A. Ozcelik
Two-loop form factors for pseudo-scalar quarkonium production and decay
37 pages, 1 figure, v2: version published in JHEP
null
10.1007/JHEP02(2023)250
BONN-TH-2022-23, CERN-TH-2022-187, TTP22-068
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the analytic expressions for the two-loop form factors for the production or decay of pseudo-scalar quarkonia, in a scheme where the quarks are produced at threshold. We consider the two-loop amplitude for the process $\gamma \gamma \leftrightarrow {^1S_0^{[1]}}$, that was previously known only numerically, as well as for the processes $gg \leftrightarrow {^1S_0^{[1]}}$, $\gamma g \leftrightarrow {^1S_0^{[8]}}$ and $gg \leftrightarrow {^1S_0^{[8]}}$, which have not been computed before. The two-loop corrections to $gg \leftrightarrow {^1S_0^{[1]}}$ are the last missing ingredients for a full NNLO calculation of $\eta_Q$ hadro-production. We discuss how the singularity structure of the amplitudes is affected by the threshold kinematics, which in particular introduces Coulomb singularities. In this context, we first show how the usual structure of the infrared singularities degenerates at threshold kinematics, and then extract the anomalous dimensions governing the Coulomb singularities for colour-singlet and octet channels, the latter being presented here for the first time. We give high-precision numerical results for the hard functions, which can be used for phenomenological studies of $\eta_Q$ production and decay at NNLO.
[ { "created": "Wed, 16 Nov 2022 11:27:26 GMT", "version": "v1" }, { "created": "Wed, 1 Mar 2023 10:49:27 GMT", "version": "v2" } ]
2023-03-22
[ [ "Abreu", "Samuel", "" ], [ "Becchetti", "Matteo", "" ], [ "Duhr", "Claude", "" ], [ "Ozcelik", "Melih A.", "" ] ]
We present the analytic expressions for the two-loop form factors for the production or decay of pseudo-scalar quarkonia, in a scheme where the quarks are produced at threshold. We consider the two-loop amplitude for the process $\gamma \gamma \leftrightarrow {^1S_0^{[1]}}$, that was previously known only numerically, as well as for the processes $gg \leftrightarrow {^1S_0^{[1]}}$, $\gamma g \leftrightarrow {^1S_0^{[8]}}$ and $gg \leftrightarrow {^1S_0^{[8]}}$, which have not been computed before. The two-loop corrections to $gg \leftrightarrow {^1S_0^{[1]}}$ are the last missing ingredients for a full NNLO calculation of $\eta_Q$ hadro-production. We discuss how the singularity structure of the amplitudes is affected by the threshold kinematics, which in particular introduces Coulomb singularities. In this context, we first show how the usual structure of the infrared singularities degenerates at threshold kinematics, and then extract the anomalous dimensions governing the Coulomb singularities for colour-singlet and octet channels, the latter being presented here for the first time. We give high-precision numerical results for the hard functions, which can be used for phenomenological studies of $\eta_Q$ production and decay at NNLO.
hep-ph/0311028
Larry McLerran
Larry McLerran
The Quark Gluon Plasma and The Color Glass Condensate: 4 Lectures
null
null
null
null
hep-ph
null
The purpose of these lectures is to provide an introduction to the physics issues which are being studied in the RHIC heavy ion program. These center around the production of new states of matter. The Quark Gluon Plasma is thermal matter which once existed in the big bang which may be made at RHIC. The Color Glass Condensate is a universal form of matter which controls the high energy limit of strong interactions. Both such forms of matter might be produced and probed at RHIC.
[ { "created": "Mon, 3 Nov 2003 19:00:45 GMT", "version": "v1" } ]
2007-05-23
[ [ "McLerran", "Larry", "" ] ]
The purpose of these lectures is to provide an introduction to the physics issues which are being studied in the RHIC heavy ion program. These center around the production of new states of matter. The Quark Gluon Plasma is thermal matter which once existed in the big bang which may be made at RHIC. The Color Glass Condensate is a universal form of matter which controls the high energy limit of strong interactions. Both such forms of matter might be produced and probed at RHIC.
1512.05617
Fredy Ochoa
R. Martinez, F. Ochoa, C.F. Sierra
Diphoton decay for a $750$ GeV scalar boson in an $U(1)_{X}$ model
5 figures, discussion extended, 2 new figures
null
10.1016/j.nuclphysb.2016.09.004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the context of a nonuniversal and anomaly free $U(1)_{X}$ extension of the standard model, we examine the decay of a $750$GeV scalar singlet state, $\xi_{\chi}$, as a possible explanation of the observed diphoton excess announced by the ATLAS and CMS collaborations at CERN-LHC collider. One-loop decay to photons is allowed through three heavy singlet quarks and one charged Higgs boson into the loop. We obtain, for different width approximations and for masses of the exotic singlet quarks in the region $[900,\,3000]$ GeV, a production cross section $\sigma(pp\to\xi_{\chi}\to\gamma\gamma)$ compatible with ATLAS and CMS collaborations data. We also include another scalar singlet, $\sigma$, as a dark matter candidate that may couple with the 750 GeV scalar at tree level with production cross sections in agreement with ATLAS and CMS.
[ { "created": "Thu, 17 Dec 2015 15:01:58 GMT", "version": "v1" }, { "created": "Mon, 21 Dec 2015 03:11:07 GMT", "version": "v2" }, { "created": "Sat, 27 Feb 2016 03:02:54 GMT", "version": "v3" }, { "created": "Wed, 27 Jul 2016 15:09:20 GMT", "version": "v4" } ]
2016-10-12
[ [ "Martinez", "R.", "" ], [ "Ochoa", "F.", "" ], [ "Sierra", "C. F.", "" ] ]
In the context of a nonuniversal and anomaly free $U(1)_{X}$ extension of the standard model, we examine the decay of a $750$GeV scalar singlet state, $\xi_{\chi}$, as a possible explanation of the observed diphoton excess announced by the ATLAS and CMS collaborations at CERN-LHC collider. One-loop decay to photons is allowed through three heavy singlet quarks and one charged Higgs boson into the loop. We obtain, for different width approximations and for masses of the exotic singlet quarks in the region $[900,\,3000]$ GeV, a production cross section $\sigma(pp\to\xi_{\chi}\to\gamma\gamma)$ compatible with ATLAS and CMS collaborations data. We also include another scalar singlet, $\sigma$, as a dark matter candidate that may couple with the 750 GeV scalar at tree level with production cross sections in agreement with ATLAS and CMS.
hep-ph/0309176
Aneesh Manohar
Aneesh V. Manohar
Deep inelastic scattering as x -> 1 using soft-collinear effective theory
19 pages, minor typos fixed, and a comment added on the longitudinal structure function
Phys.Rev. D68 (2003) 114019
10.1103/PhysRevD.68.114019
null
hep-ph
null
Soft-collinear effective theory (SCET) is used to sum Sudakov double-logarithms in the x ->1 endpoint region for the deep inelastic scattering structure function. The calculations are done in both the target rest frame and the Breit frame. The separation of scales in the effective theory implies that the anomalous dimension of the SCET current is linear in ln mu, and the anomalous dimension for the Nth moment of the structure function is linear in ln N, to all orders in perturbation theory. The SCET formulation is shown to be free of Landau pole singularities. Some important differences between the deep inelastic structure function and the shape function in B decay are discussed.
[ { "created": "Tue, 16 Sep 2003 19:27:52 GMT", "version": "v1" }, { "created": "Tue, 6 Jan 2004 21:47:31 GMT", "version": "v2" } ]
2009-11-10
[ [ "Manohar", "Aneesh V.", "" ] ]
Soft-collinear effective theory (SCET) is used to sum Sudakov double-logarithms in the x ->1 endpoint region for the deep inelastic scattering structure function. The calculations are done in both the target rest frame and the Breit frame. The separation of scales in the effective theory implies that the anomalous dimension of the SCET current is linear in ln mu, and the anomalous dimension for the Nth moment of the structure function is linear in ln N, to all orders in perturbation theory. The SCET formulation is shown to be free of Landau pole singularities. Some important differences between the deep inelastic structure function and the shape function in B decay are discussed.
hep-ph/9604429
Chi-Sing Lam
Y.J. Feng, O. Hamidi-Ravari, and C. S. Lam
Cut Diagrams for High Energy Scatterings
uu-encoded file containing a latex manuscript with 14 postscript figures
Phys.Rev.D54:3114-3124,1996
10.1103/PhysRevD.54.3114
McGill/96-13
hep-ph
null
A new approach is introduced to study QCD amplitudes at high energy and comparatively small momentum transfer. Novel cut diagrams, representing resummation of Feynman diagrams, are used to simplify calculation and to avoid delicate cancellations encountered in the usual approach. Explicit calculation to the 6th order is carried out to demonstrate the advantage of cut diagrams over Feynman diagrams.
[ { "created": "Mon, 29 Apr 1996 15:33:17 GMT", "version": "v1" } ]
2014-11-17
[ [ "Feng", "Y. J.", "" ], [ "Hamidi-Ravari", "O.", "" ], [ "Lam", "C. S.", "" ] ]
A new approach is introduced to study QCD amplitudes at high energy and comparatively small momentum transfer. Novel cut diagrams, representing resummation of Feynman diagrams, are used to simplify calculation and to avoid delicate cancellations encountered in the usual approach. Explicit calculation to the 6th order is carried out to demonstrate the advantage of cut diagrams over Feynman diagrams.
0712.4187
Chun-Khiang Chua
Chun-Khiang Chua
Rescattering effects in charmless B_{u,d,s} to P P decays
33 pages, 6 figures, version to appear in Phys. Rev. D
Phys.Rev.D78:076002,2008
10.1103/PhysRevD.78.076002
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the final-state interaction (FSI) effects in charmless B_{u,d,s} to PP decays. We consider a FSI approach with both short- and long-distance contributions, where the former are from in-elastic channels and are contained in factorization amplitudes, while the latter are from the residual rescattering among PP states. Flavor SU(3) symmetry is used to constrain the residual rescattering S-matrix. We fit to all available data on the CP-averaged decay rates and CP asymmetries, and make predictions on unmeasured ones. Our main results are as follows: (i) Results are in agreement with data in the presence of FSI. (ii) For B decays, the pi^+pi^- and pi^0pi^0 rates are suppressed and enhanced respectively by FSI. (iii) The FSI has a large impact on direct CP asymmetries of many modes. (iv) The deviation (Delta A) between A(B{bar}^0 to K^-pi^+) and A(B^-to K^-\pi^0) can be understood in the FSI approach. (v) Sizable and complex color-suppressed tree amplitudes, which are crucial for the large \pi^0\pi^0 rate and Delta A, are generated through exchange rescattering. The correlation of the ratio B(pi^0pi^0)/B(pi^+pi^-) and Delta A is studied. (vi) The B^- to pi^-pi^0 direct CP violation is very small and is not affected by FSI. (vii) Several B_s decay rates are enhanced. In particular, the eta'eta' branching ratio is enhanced to the level of 1.0X10^{-4}, which can be checked experimentally. (viii) Time-dependent CP asymmetries S in B_{d,s} decays are studied. CP asymmetries in these modes will be useful to test the SM.
[ { "created": "Thu, 27 Dec 2007 13:42:14 GMT", "version": "v1" }, { "created": "Wed, 9 Jan 2008 12:14:36 GMT", "version": "v2" }, { "created": "Tue, 9 Sep 2008 07:32:20 GMT", "version": "v3" } ]
2008-11-26
[ [ "Chua", "Chun-Khiang", "" ] ]
We study the final-state interaction (FSI) effects in charmless B_{u,d,s} to PP decays. We consider a FSI approach with both short- and long-distance contributions, where the former are from in-elastic channels and are contained in factorization amplitudes, while the latter are from the residual rescattering among PP states. Flavor SU(3) symmetry is used to constrain the residual rescattering S-matrix. We fit to all available data on the CP-averaged decay rates and CP asymmetries, and make predictions on unmeasured ones. Our main results are as follows: (i) Results are in agreement with data in the presence of FSI. (ii) For B decays, the pi^+pi^- and pi^0pi^0 rates are suppressed and enhanced respectively by FSI. (iii) The FSI has a large impact on direct CP asymmetries of many modes. (iv) The deviation (Delta A) between A(B{bar}^0 to K^-pi^+) and A(B^-to K^-\pi^0) can be understood in the FSI approach. (v) Sizable and complex color-suppressed tree amplitudes, which are crucial for the large \pi^0\pi^0 rate and Delta A, are generated through exchange rescattering. The correlation of the ratio B(pi^0pi^0)/B(pi^+pi^-) and Delta A is studied. (vi) The B^- to pi^-pi^0 direct CP violation is very small and is not affected by FSI. (vii) Several B_s decay rates are enhanced. In particular, the eta'eta' branching ratio is enhanced to the level of 1.0X10^{-4}, which can be checked experimentally. (viii) Time-dependent CP asymmetries S in B_{d,s} decays are studied. CP asymmetries in these modes will be useful to test the SM.
1812.09258
Andrei Kataev
A.L. Kataev and V.S. Molokoedov
The least squares method: application to analysis of the flavor dependence of the QCD relation between pole and $\rm{\overline{MS}}$-scheme running heavy quark masses
9 pages, 1 Table
null
10.1134/S0040577919090101
INR-TH-2018-034
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The features of the ordinary least squares method, which gives a possible way to a solution of the overdetermined systems of algebraic equations and allows to estimate the uncertainties of the obtained solutions, are considered. As the important physical example we define four-loop QCD coefficients in the dependence of the relation between pole and running heavy quarks masses on the number of light flavors, using the existing results of numerical supercomputer based calculations of the corresponding four-loop contributions at different fixed numbers of light flavors. Stability of the found solutions to the number of the considered equations and unknowns is demonstrated and supported by the Pearsons's $\chi$-squared test.
[ { "created": "Thu, 20 Dec 2018 15:26:31 GMT", "version": "v1" } ]
2019-10-23
[ [ "Kataev", "A. L.", "" ], [ "Molokoedov", "V. S.", "" ] ]
The features of the ordinary least squares method, which gives a possible way to a solution of the overdetermined systems of algebraic equations and allows to estimate the uncertainties of the obtained solutions, are considered. As the important physical example we define four-loop QCD coefficients in the dependence of the relation between pole and running heavy quarks masses on the number of light flavors, using the existing results of numerical supercomputer based calculations of the corresponding four-loop contributions at different fixed numbers of light flavors. Stability of the found solutions to the number of the considered equations and unknowns is demonstrated and supported by the Pearsons's $\chi$-squared test.
hep-ph/0010276
Josep Taron
A.A. Andrianov, R.Tarrach, J.Taron
Neutral Kaons in Medium: Decoherence Effects
null
Phys.Lett. B507 (2001) 200-206
10.1016/S0370-2693(01)00463-4
null
hep-ph quant-ph
null
We consider departures from hamiltonian dynamics in the evolution of neutral kaons due to their interactions with environment that generate entanglement among them. We propose a phenomenological model of stochastic re-scattering and estimate the coefficients of the effective hamiltonian and decoherence terms. Finally we analyze the interplay between the weak interaction and matter effects and propose the observables suitable to measure the matter characteristics of CPT violation and decoherence.
[ { "created": "Tue, 24 Oct 2000 15:51:48 GMT", "version": "v1" }, { "created": "Wed, 25 Oct 2000 13:14:14 GMT", "version": "v2" } ]
2009-10-31
[ [ "Andrianov", "A. A.", "" ], [ "Tarrach", "R.", "" ], [ "Taron", "J.", "" ] ]
We consider departures from hamiltonian dynamics in the evolution of neutral kaons due to their interactions with environment that generate entanglement among them. We propose a phenomenological model of stochastic re-scattering and estimate the coefficients of the effective hamiltonian and decoherence terms. Finally we analyze the interplay between the weak interaction and matter effects and propose the observables suitable to measure the matter characteristics of CPT violation and decoherence.
2110.06824
Sergiy Akkelin
M.D. Adzhymambetov, S.V. Akkelin, Yu.M. Sinyukov
Fixed particle number constraint in a simple model of a thermal expanding system and $pp$ collisions at the LHC
21 pages, 6 figures
Phys. Rev. D 105, 096035 (2022)
10.1103/PhysRevD.105.096035
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Two-boson momentum correlations at fixed particle number constraint are studied in a simple analytically solvable model of a thermal expanding system. We show that the increase of expansion rate, as well as increase of particle multiplicity, enhances the ground-state contribution to particle momentum spectra and leads to suppression of the Bose-Einstein momentum correlations. The relations of these findings to the multiplicity-dependent measurements of the Bose-Einstein momentum correlations in high-multiplicity $p+p$ collision events at the LHC are discussed.
[ { "created": "Wed, 13 Oct 2021 16:11:02 GMT", "version": "v1" }, { "created": "Sat, 5 Feb 2022 14:56:57 GMT", "version": "v2" }, { "created": "Mon, 30 May 2022 12:37:22 GMT", "version": "v3" } ]
2022-05-31
[ [ "Adzhymambetov", "M. D.", "" ], [ "Akkelin", "S. V.", "" ], [ "Sinyukov", "Yu. M.", "" ] ]
Two-boson momentum correlations at fixed particle number constraint are studied in a simple analytically solvable model of a thermal expanding system. We show that the increase of expansion rate, as well as increase of particle multiplicity, enhances the ground-state contribution to particle momentum spectra and leads to suppression of the Bose-Einstein momentum correlations. The relations of these findings to the multiplicity-dependent measurements of the Bose-Einstein momentum correlations in high-multiplicity $p+p$ collision events at the LHC are discussed.
2112.07274
Jorge De Blas
J. de Blas, M. Ciuchini, E. Franco, A. Goncalves, S. Mishima, M. Pierini, L. Reina and L. Silvestrini
Global analysis of electroweak data in the Standard Model
11 pages, 4 tables, 3 figures
null
10.1103/PhysRevD.106.033003
KEK-TH-2378
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform a global fit of electroweak data within the Standard Model, using state-of-the art experimental and theoretical results, including a determination of the electromagnetic coupling at the electroweak scale based on recent lattice calculations. In addition to the posteriors for all parameters and observables obtained from the global fit, we present indirect determinations for all parameters and predictions for all observables. Furthermore, we present full predictions, obtained using only the experimental information on Standard Model parameters, and a fully indirect determination of Standard Model parameters using only experimental information on electroweak data. Finally, we discuss in detail the compatibility of experimental data with the Standard Model and find a global p-value of 0.5.
[ { "created": "Tue, 14 Dec 2021 10:10:00 GMT", "version": "v1" } ]
2022-08-17
[ [ "de Blas", "J.", "" ], [ "Ciuchini", "M.", "" ], [ "Franco", "E.", "" ], [ "Goncalves", "A.", "" ], [ "Mishima", "S.", "" ], [ "Pierini", "M.", "" ], [ "Reina", "L.", "" ], [ "Silvestrini", "L.", "" ] ]
We perform a global fit of electroweak data within the Standard Model, using state-of-the art experimental and theoretical results, including a determination of the electromagnetic coupling at the electroweak scale based on recent lattice calculations. In addition to the posteriors for all parameters and observables obtained from the global fit, we present indirect determinations for all parameters and predictions for all observables. Furthermore, we present full predictions, obtained using only the experimental information on Standard Model parameters, and a fully indirect determination of Standard Model parameters using only experimental information on electroweak data. Finally, we discuss in detail the compatibility of experimental data with the Standard Model and find a global p-value of 0.5.
hep-ph/9806280
Jos Vermaseren
J. A. M. Vermaseren
Harmonic sums, Mellin transforms and Integrals
31 pages LaTeX, for programs, see http://norma.nikhef.nl/~t68/summer
Int.J.Mod.Phys.A14:2037-2076,1999
10.1142/S0217751X99001032
FTUAM-98-7, NIKHEF-98-14
hep-ph
null
This paper describes algorithms to deal with nested symbolic sums over combinations of harmonic series, binomial coefficients and denominators. In addition it treats Mellin transforms and the inverse Mellin transformation for functions that are encountered in Feynman diagram calculations. Together with results for the values of the higher harmonic series at infinity the presented algorithms can be used for the symbolic evaluation of whole classes of integrals that were thus far intractable. Also many of the sums that had to be evaluated seem to involve new results. Most of the algorithms have been programmed in the language of FORM. The resulting set of procedures is called SUMMER.
[ { "created": "Fri, 5 Jun 1998 14:31:34 GMT", "version": "v1" } ]
2008-11-26
[ [ "Vermaseren", "J. A. M.", "" ] ]
This paper describes algorithms to deal with nested symbolic sums over combinations of harmonic series, binomial coefficients and denominators. In addition it treats Mellin transforms and the inverse Mellin transformation for functions that are encountered in Feynman diagram calculations. Together with results for the values of the higher harmonic series at infinity the presented algorithms can be used for the symbolic evaluation of whole classes of integrals that were thus far intractable. Also many of the sums that had to be evaluated seem to involve new results. Most of the algorithms have been programmed in the language of FORM. The resulting set of procedures is called SUMMER.
1805.00198
Yigal Shamir
Maarten Golterman and Yigal Shamir
The large-mass regime of the dilaton-pion low-energy effective theory
RevTeX, 16 pages. Major revision, more insight into the nature of the expansion in the large-mass regime
Phys. Rev. D 98, 056025 (2018)
10.1103/PhysRevD.98.056025
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Numerical data of the SU(3) gauge theory with $N_f=8$ fermions in the fundamental representation suggest the existence of a large-mass regime, where the fermion mass is not small relative to the confinement scale, but nevertheless the dilaton-pion low-energy theory is applicable thanks to the parametric proximity of the conformal window. In this regime, the leading hyperscaling relations are similar to those of a mass-deformed conformal theory, so that distinguishing infrared conformality from confinement requires the study of subleading effects. Assuming that the $N_f=8$ theory confines, we estimate how light the fermion mass should be to enter the small-mass regime, where the pions become much lighter than the dilatonic scalar meson.
[ { "created": "Tue, 1 May 2018 06:18:55 GMT", "version": "v1" }, { "created": "Tue, 7 Aug 2018 07:17:28 GMT", "version": "v2" } ]
2018-10-03
[ [ "Golterman", "Maarten", "" ], [ "Shamir", "Yigal", "" ] ]
Numerical data of the SU(3) gauge theory with $N_f=8$ fermions in the fundamental representation suggest the existence of a large-mass regime, where the fermion mass is not small relative to the confinement scale, but nevertheless the dilaton-pion low-energy theory is applicable thanks to the parametric proximity of the conformal window. In this regime, the leading hyperscaling relations are similar to those of a mass-deformed conformal theory, so that distinguishing infrared conformality from confinement requires the study of subleading effects. Assuming that the $N_f=8$ theory confines, we estimate how light the fermion mass should be to enter the small-mass regime, where the pions become much lighter than the dilatonic scalar meson.
0812.1299
Chung-I Tan
Richard C. Brower, Marko Djuric, and Chung-I Tan
Saturation and Confinement: Analyticity, Unitarity and AdS/CFT Correspondence
more references added. presented at ISMD 2008, 15-20 Sept. 2008
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In $1/N_c$ expansion, analyticity and crossing lead to crossing even and odd ($C=\pm 1$) vacuum exchanges at high-energy, the {\em Pomeron} and the {\em Odderon}. We discuss how, using {\em String/Gauge duality}, these can be identified with a reggeized {\em Graviton} and the anti-symmetric {\em Kalb-Ramond fields} in $AdS$ background. With confinement, these Regge singularities interpolate with glueball states. We also discuss unitarization based on eikonal sum in $AdS$.
[ { "created": "Sat, 6 Dec 2008 22:22:12 GMT", "version": "v1" }, { "created": "Wed, 10 Dec 2008 20:16:56 GMT", "version": "v2" } ]
2008-12-10
[ [ "Brower", "Richard C.", "" ], [ "Djuric", "Marko", "" ], [ "Tan", "Chung-I", "" ] ]
In $1/N_c$ expansion, analyticity and crossing lead to crossing even and odd ($C=\pm 1$) vacuum exchanges at high-energy, the {\em Pomeron} and the {\em Odderon}. We discuss how, using {\em String/Gauge duality}, these can be identified with a reggeized {\em Graviton} and the anti-symmetric {\em Kalb-Ramond fields} in $AdS$ background. With confinement, these Regge singularities interpolate with glueball states. We also discuss unitarization based on eikonal sum in $AdS$.
hep-ph/0512297
Mar\'ia Catalina Espinoza Hern\'andez
J. Bernabeu, J. Burguet-Castell, C. Espinoza and M. Lindroos
Physics Reach with a Monochromatic Neutrino Beam from Electron Capture
4 pages, 1 figure. Talk given at the International Europhysics Conference on High Energy Physics, HEP-EPS 2005, Lisbon, Portugal, July 21-27, 2005
null
null
null
hep-ph
null
Neutrino oscillation experiments from different sources have demonstrated non-vanishing neutrino masses and flavour mixings. The next experiments have to address the determination of the connecting mixing U(e3) and the existence of the CP violating phase. Whereas U(e3) measures the strength of the oscillation probability in appearance experiments, the CP phase acts as a phase-shift in the interference pattern. Here we propose to separate these two parameters by energy dependence, using the novel idea of a monochromatic neutrino beam facility based on the acceleration of ions that decay fast through electron capture. Fine tuning of the boosted neutrino energy allows precision measurements able to open a window for the discovery of CP violation, even for a mixing as small as 1 degree.
[ { "created": "Thu, 22 Dec 2005 12:59:22 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bernabeu", "J.", "" ], [ "Burguet-Castell", "J.", "" ], [ "Espinoza", "C.", "" ], [ "Lindroos", "M.", "" ] ]
Neutrino oscillation experiments from different sources have demonstrated non-vanishing neutrino masses and flavour mixings. The next experiments have to address the determination of the connecting mixing U(e3) and the existence of the CP violating phase. Whereas U(e3) measures the strength of the oscillation probability in appearance experiments, the CP phase acts as a phase-shift in the interference pattern. Here we propose to separate these two parameters by energy dependence, using the novel idea of a monochromatic neutrino beam facility based on the acceleration of ions that decay fast through electron capture. Fine tuning of the boosted neutrino energy allows precision measurements able to open a window for the discovery of CP violation, even for a mixing as small as 1 degree.
2312.05776
Rie Inumiya
Gi-Chol Cho, Chikako Idegawa and Rie Inumiya
A complex singlet extension of the Standard Model with a singlet fermion dark matter
16 pages, 4 figures
null
null
OCHA-PP-378
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine a complex singlet scalar extension of the Standard Model (CxSM) with an extra singlet fermion. Both the singlet scalar and fermion are dark matter (DM) candidates. It is known that although the scalar potential in the CxSM can realize strong first-order electroweak phase transition, the scalar DM included in the model gives only a tiny amount of the relic density compared to the observed one. Therefore, a fermion DM is introduced to compensate for the lack of relic density. We find that the scattering of the fermion DM and nucleons is sufficiently suppressed when the masses of scalar mediators are degenerate, as well as in the case of the scalar DM. We show the range of a combination of the mass and the Yukawa coupling of the fermion DM, which satisfies both the observed relic density and conditions of strong first-order electroweak phase transition.
[ { "created": "Sun, 10 Dec 2023 05:50:26 GMT", "version": "v1" } ]
2023-12-12
[ [ "Cho", "Gi-Chol", "" ], [ "Idegawa", "Chikako", "" ], [ "Inumiya", "Rie", "" ] ]
We examine a complex singlet scalar extension of the Standard Model (CxSM) with an extra singlet fermion. Both the singlet scalar and fermion are dark matter (DM) candidates. It is known that although the scalar potential in the CxSM can realize strong first-order electroweak phase transition, the scalar DM included in the model gives only a tiny amount of the relic density compared to the observed one. Therefore, a fermion DM is introduced to compensate for the lack of relic density. We find that the scattering of the fermion DM and nucleons is sufficiently suppressed when the masses of scalar mediators are degenerate, as well as in the case of the scalar DM. We show the range of a combination of the mass and the Yukawa coupling of the fermion DM, which satisfies both the observed relic density and conditions of strong first-order electroweak phase transition.
hep-ph/9501318
null
Eugene Golowich and Joachim Kambor
Two-Loop Analysis of Vector Current Propagators in Chiral Perturbation Theory
To appear in Nucl. Phys. B (Changes in Sects. 4,8)
Nucl.Phys. B447 (1995) 373-404
10.1016/0550-3213(95)00234-J
UMHEP-414
hep-ph
null
We perform a calculation of the isospin and hypercharge vector current propagators ($\Delta_{V33}^{\mu\nu}(q^2)$ and $\Delta_{V88}^{\mu\nu}(q^2)$) to two loops in chiral perturbation theory. The analysis is carried out with straightforward Feynman diagram methods by making appropriate use of external vector sources. Counterterms from the ${\cal O}(q^6)$ chiral lagrangian, required to absorb divergences and scale dependence encountered at the two-loop level, are constructed. Our final results are finite, covariant, and scale-independent. Several applications are described, including a comparison of the two-loop isospin vector spectral function with data and the construction of new chiral sum rules.
[ { "created": "Tue, 17 Jan 1995 14:15:04 GMT", "version": "v1" }, { "created": "Mon, 22 May 1995 14:56:59 GMT", "version": "v2" }, { "created": "Tue, 23 May 1995 21:04:18 GMT", "version": "v3" } ]
2009-10-28
[ [ "Golowich", "Eugene", "" ], [ "Kambor", "Joachim", "" ] ]
We perform a calculation of the isospin and hypercharge vector current propagators ($\Delta_{V33}^{\mu\nu}(q^2)$ and $\Delta_{V88}^{\mu\nu}(q^2)$) to two loops in chiral perturbation theory. The analysis is carried out with straightforward Feynman diagram methods by making appropriate use of external vector sources. Counterterms from the ${\cal O}(q^6)$ chiral lagrangian, required to absorb divergences and scale dependence encountered at the two-loop level, are constructed. Our final results are finite, covariant, and scale-independent. Several applications are described, including a comparison of the two-loop isospin vector spectral function with data and the construction of new chiral sum rules.
2003.00640
Avik Roy
Avik Roy, Nikiforos Nikiforou, Nuno Castro, Timothy Andeen
Novel Interpretation Strategy for Searches of Singly Produced Vector-like Quarks at the LHC
22 pages, 8 figures, 4 tables
Phys. Rev. D 101, 115027 (2020)
10.1103/PhysRevD.101.115027
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Vector-like Quarks (VLQs) are potential signatures of physics beyond the Standard Model at the TeV energy scale and major efforts have been put forward at both ATLAS and CMS experiments in search of these particles. In order to make these search results more relatable in the context of most plausible theories of VLQs, it is deemed important to present the analysis results in a general fashion. We investigate the challenges associated with such interpretations of singly produced VLQ searches and propose a generalized, semi-analytical framework that allows a model-independent casting of the results in terms of unconstrained, free parameters of the VLQ Lagrangian. We also propose a simple parameterization of the correction factor to the single VLQ production cross-section at large decay widths. We illustrate how the proposed framework can be used to conveniently represent statistical limits by numerically reinterpreting results from benchmark ATLAS and CMS analyses.
[ { "created": "Mon, 2 Mar 2020 03:19:42 GMT", "version": "v1" }, { "created": "Wed, 3 Jun 2020 18:02:07 GMT", "version": "v2" }, { "created": "Wed, 24 Jun 2020 15:23:00 GMT", "version": "v3" } ]
2020-07-01
[ [ "Roy", "Avik", "" ], [ "Nikiforou", "Nikiforos", "" ], [ "Castro", "Nuno", "" ], [ "Andeen", "Timothy", "" ] ]
Vector-like Quarks (VLQs) are potential signatures of physics beyond the Standard Model at the TeV energy scale and major efforts have been put forward at both ATLAS and CMS experiments in search of these particles. In order to make these search results more relatable in the context of most plausible theories of VLQs, it is deemed important to present the analysis results in a general fashion. We investigate the challenges associated with such interpretations of singly produced VLQ searches and propose a generalized, semi-analytical framework that allows a model-independent casting of the results in terms of unconstrained, free parameters of the VLQ Lagrangian. We also propose a simple parameterization of the correction factor to the single VLQ production cross-section at large decay widths. We illustrate how the proposed framework can be used to conveniently represent statistical limits by numerically reinterpreting results from benchmark ATLAS and CMS analyses.
hep-ph/0201047
Nelly Goguitidze
N. Gogitidze (on behalf of the H1 and ZEUS collaborations)
Determination of the longitudinal structure function $F_{L}$ at HERA
16 pages, 11 figures (requires iopart, iopams and epsfig); Talk presented in the Intern. Workshop on New Trends in HERA Physics 2001, 17-22 June 2001, Ringberg Castle, Tegernsee, Germany; To appear in the Proceedings
J.Phys.G28:751-766,2002
10.1088/0954-3899/28/5/303
null
hep-ph
null
Recent results from the HERA experiment H1 on the longitudinal stucture function $F_{L}$ of the proton are presented. They include proton structure function analyses with particular emphasis on those kinematic regions which are sensitive to $F_{L}$. All results can be consistently described within the framework of perturbative QCD.
[ { "created": "Tue, 8 Jan 2002 12:37:11 GMT", "version": "v1" } ]
2008-11-26
[ [ "Gogitidze", "N.", "", "on behalf of the H1 and ZEUS collaborations" ] ]
Recent results from the HERA experiment H1 on the longitudinal stucture function $F_{L}$ of the proton are presented. They include proton structure function analyses with particular emphasis on those kinematic regions which are sensitive to $F_{L}$. All results can be consistently described within the framework of perturbative QCD.
hep-ph/0003035
Michael Kraemer
Michael Kr\"amer, Fredrick I. Olness, Davison E. Soper
Treatment of Heavy Quarks in Deeply Inelastic Scattering
14 pages, 5 figures
Phys.Rev.D62:096007,2000
10.1103/PhysRevD.62.096007
Edinburgh 2000/02
hep-ph
null
We investigate a simplified version of the ACOT prescription for calculating deeply inelastic scattering from Q^2 values near the squared mass M_H^2 of a heavy quark to Q^2 much larger than M_H^2.
[ { "created": "Sun, 5 Mar 2000 13:59:24 GMT", "version": "v1" } ]
2008-11-26
[ [ "Krämer", "Michael", "" ], [ "Olness", "Fredrick I.", "" ], [ "Soper", "Davison E.", "" ] ]
We investigate a simplified version of the ACOT prescription for calculating deeply inelastic scattering from Q^2 values near the squared mass M_H^2 of a heavy quark to Q^2 much larger than M_H^2.
hep-ph/0103052
Steve Geer
V. Barger, et al
Oscillation Measurements with Upgraded Conventional Neutrino Beams
42 pages, 20 figures
null
null
FERMILAB-FN-703
hep-ph
null
We consider the nu_mu to nu_e oscillation measurements that would be possible at upgraded 1 GeV and multi-GeV conventional neutrino sources driven by future megawatt-scale proton drivers. If these neutrino superbeams are used together with detectors that are an order of magnitude larger than those presently foreseen, we find that the sensitivity to nu_mu to nu_e oscillations can be improved by an order of magnitude beyond the next generation of accelerator based experiments. In addition, over a limited region of parameter space, the neutrino mass hierarchy can be determined with a multi-GeV long baseline beam. If the Large Mixing Angle MSW solution correctly describes the solar neutrino deficit, there is a small corner of allowed parameter space in which maximal CP-violation in the lepton sector might be observable at a 1 GeV medium baseline experiment. Superbeams with massive detectors would therefore provide a useful tool en route to a neutrino factory, which would permit a further order of magnitude improvement in sensitivity, together with a more comprehensive check of CP-violation and the oscillation framework.
[ { "created": "Mon, 5 Mar 2001 22:57:45 GMT", "version": "v1" }, { "created": "Tue, 6 Mar 2001 18:51:55 GMT", "version": "v2" } ]
2007-05-23
[ [ "Barger", "V.", "" ] ]
We consider the nu_mu to nu_e oscillation measurements that would be possible at upgraded 1 GeV and multi-GeV conventional neutrino sources driven by future megawatt-scale proton drivers. If these neutrino superbeams are used together with detectors that are an order of magnitude larger than those presently foreseen, we find that the sensitivity to nu_mu to nu_e oscillations can be improved by an order of magnitude beyond the next generation of accelerator based experiments. In addition, over a limited region of parameter space, the neutrino mass hierarchy can be determined with a multi-GeV long baseline beam. If the Large Mixing Angle MSW solution correctly describes the solar neutrino deficit, there is a small corner of allowed parameter space in which maximal CP-violation in the lepton sector might be observable at a 1 GeV medium baseline experiment. Superbeams with massive detectors would therefore provide a useful tool en route to a neutrino factory, which would permit a further order of magnitude improvement in sensitivity, together with a more comprehensive check of CP-violation and the oscillation framework.
hep-ph/9509428
null
Amol S. Dighe, Michael Gronau and Jonathan L. Rosner
Amplitude relations for $B$ decays involving $\eta$ and $\eta'$
7 pages, latex, 1 uuencoded figure
Phys.Lett.B367:357-361,1996; ERRATUM-ibid.B377:325,1996
10.1016/0370-2693(95)01341-5
TECHNION-PH-95-27, EFI-95-60
hep-ph
null
A class of amplitude relations for decays of $B$ mesons is discussed. Processes involving $\eta$ and $\eta'$ in the final state are shown to provide useful information about weak phases in some cases even in the presence of octet-singlet mixing in these states. Some of the relations are unaffected by first-order SU(3) breaking.
[ { "created": "Fri, 29 Sep 1995 20:24:39 GMT", "version": "v1" } ]
2011-07-19
[ [ "Dighe", "Amol S.", "" ], [ "Gronau", "Michael", "" ], [ "Rosner", "Jonathan L.", "" ] ]
A class of amplitude relations for decays of $B$ mesons is discussed. Processes involving $\eta$ and $\eta'$ in the final state are shown to provide useful information about weak phases in some cases even in the presence of octet-singlet mixing in these states. Some of the relations are unaffected by first-order SU(3) breaking.
2107.07074
Naoki Yamamoto
Akihiro Yamada, Naoki Yamamoto
Floquet vacuum engineering: Laser-driven chiral soliton lattice in the QCD vacuum
7 pages; v2: added discussion of Weyl/Dirac semimetals, typos fixed, published version
Phys. Rev. D 104, 054041 (2021)
10.1103/PhysRevD.104.054041
null
hep-ph cond-mat.str-el hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
What happens to the QCD vacuum when a time-periodic circularly polarized laser field with a sufficiently large intensity and frequency is applied? Based on the Floquet formalism for periodically driven systems and the systematic low-energy effective theory of QCD, we show that for a sufficiently large frequency and above a critical intensity, the QCD vacuum is unstable against the chiral soliton lattice of pions; a crystalline structure of topological solitons that spontaneously breaks parity and continuous translational symmetries. Our work would pave the way for novel "Floquet vacuum engineering."
[ { "created": "Thu, 15 Jul 2021 02:11:03 GMT", "version": "v1" }, { "created": "Thu, 30 Sep 2021 13:28:05 GMT", "version": "v2" } ]
2021-10-01
[ [ "Yamada", "Akihiro", "" ], [ "Yamamoto", "Naoki", "" ] ]
What happens to the QCD vacuum when a time-periodic circularly polarized laser field with a sufficiently large intensity and frequency is applied? Based on the Floquet formalism for periodically driven systems and the systematic low-energy effective theory of QCD, we show that for a sufficiently large frequency and above a critical intensity, the QCD vacuum is unstable against the chiral soliton lattice of pions; a crystalline structure of topological solitons that spontaneously breaks parity and continuous translational symmetries. Our work would pave the way for novel "Floquet vacuum engineering."
2107.09671
Dario Bettoni
Dario Bettoni, Asier Lopez-Eiguren, Javier Rubio
Hubble-induced phase transitions on the lattice with applications to Ricci reheating
26 pages, 12 figures, 1 appendix. Minor revisions, updated references, matches published version. Computer generated movies of the simulation are available at https://youtube.com/playlist?list=PLl1K9-81ct6yHh6boyTiZAfNv_zlwux7-
null
10.1088/1475-7516/2022/01/002
null
hep-ph astro-ph.CO gr-qc hep-lat
http://creativecommons.org/licenses/by/4.0/
Using 3+1 classical lattice simulations, we follow the symmetry breaking pattern and subsequent non-linear evolution of a spectator field non-minimally coupled to gravity when the post-inflationary dynamics is given in terms of a stiff equation-of-state parameter. We find that the gradient energy density immediately after the transition represents a non-negligible fraction of the total energy budget, steadily growing to equal the kinetic counterpart. This behaviour is reflected on the evolution of the associated equation-of-state parameter, which approaches a universal value $1/3$, independently of the shape of non-linear interactions. Combined with kination, this observation allows for the generic onset of radiation domination for arbitrary self-interacting potentials, significantly extending previous results in the literature. The produced spectrum at that time is, however, non-thermal, precluding the naive extraction of thermodynamical quantities like temperature. Potential identifications of the spectator field with the Standard Model Higgs are also discussed.
[ { "created": "Tue, 20 Jul 2021 16:39:55 GMT", "version": "v1" }, { "created": "Mon, 10 Jan 2022 09:43:56 GMT", "version": "v2" } ]
2022-01-11
[ [ "Bettoni", "Dario", "" ], [ "Lopez-Eiguren", "Asier", "" ], [ "Rubio", "Javier", "" ] ]
Using 3+1 classical lattice simulations, we follow the symmetry breaking pattern and subsequent non-linear evolution of a spectator field non-minimally coupled to gravity when the post-inflationary dynamics is given in terms of a stiff equation-of-state parameter. We find that the gradient energy density immediately after the transition represents a non-negligible fraction of the total energy budget, steadily growing to equal the kinetic counterpart. This behaviour is reflected on the evolution of the associated equation-of-state parameter, which approaches a universal value $1/3$, independently of the shape of non-linear interactions. Combined with kination, this observation allows for the generic onset of radiation domination for arbitrary self-interacting potentials, significantly extending previous results in the literature. The produced spectrum at that time is, however, non-thermal, precluding the naive extraction of thermodynamical quantities like temperature. Potential identifications of the spectator field with the Standard Model Higgs are also discussed.
2006.08758
Kamel Khelifa-Kerfa
Kamel Khelifa-Kerfa, Yazid Delenda
Eikonal amplitudes for three-hard legs processes at finite-N$_c$
6 pages. Published version
Physics Letters B 809 (2020) 135768
10.1016/j.physletb.2020.135768
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend our previous work on scattering amplitudes [1] to hadron collisions. We provide a general formalism for the computation of eikonal amplitudes squared for the radiation of soft and energy-ordered gluons off three hard-legs at finite-N$_c$ to any order in the perturbative expansion. Examples of three-hard legs processes include vector/Higgs boson production in association with a single hard jet and dijet production in DIS. Explicit expressions for the radiation of up to four gluons are provided as an illustration of the formalism.
[ { "created": "Mon, 15 Jun 2020 20:50:32 GMT", "version": "v1" }, { "created": "Mon, 14 Sep 2020 11:23:15 GMT", "version": "v2" } ]
2020-09-15
[ [ "Khelifa-Kerfa", "Kamel", "" ], [ "Delenda", "Yazid", "" ] ]
We extend our previous work on scattering amplitudes [1] to hadron collisions. We provide a general formalism for the computation of eikonal amplitudes squared for the radiation of soft and energy-ordered gluons off three hard-legs at finite-N$_c$ to any order in the perturbative expansion. Examples of three-hard legs processes include vector/Higgs boson production in association with a single hard jet and dijet production in DIS. Explicit expressions for the radiation of up to four gluons are provided as an illustration of the formalism.
1407.6010
Mark Hertzberg
Mark P. Hertzberg, Frank Wilczek
Inflation Driven by Unification Energy
5 double column pages, 1 figure. V2: Updated to resemble version published in PRD
Phys. Rev. D 95, 063516 (2017)
10.1103/PhysRevD.95.063516
MIT-CTP 4551
hep-ph astro-ph.CO gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the hypothesis that inflation is primarily driven by vacuum energy at a scale indicated by gauge coupling unification. Concretely, we consider a class of hybrid inflation models wherein the vacuum energy associated with a grand unified theory condensate provides the dominant energy during inflation, while a second "inflaton" scalar slow-rolls. We show that it is possible to obtain significant tensor-to-scalar ratios while fitting the observed spectral index.
[ { "created": "Tue, 22 Jul 2014 20:00:26 GMT", "version": "v1" }, { "created": "Sun, 26 Mar 2017 03:25:56 GMT", "version": "v2" } ]
2017-03-28
[ [ "Hertzberg", "Mark P.", "" ], [ "Wilczek", "Frank", "" ] ]
We examine the hypothesis that inflation is primarily driven by vacuum energy at a scale indicated by gauge coupling unification. Concretely, we consider a class of hybrid inflation models wherein the vacuum energy associated with a grand unified theory condensate provides the dominant energy during inflation, while a second "inflaton" scalar slow-rolls. We show that it is possible to obtain significant tensor-to-scalar ratios while fitting the observed spectral index.
hep-ph/0008236
Adam K. Leibovich
Adam K Leibovich
Quarkonium production and NRQCD matrix elements
6 pages, 1 figure, talk given at 4th International Conference on Hyperons, Charm and Beauty Hadrons, Valencia, Spain, 27-30 Jun 2000
Nucl.Phys.Proc.Suppl. 93 (2001) 182-187
10.1016/S0920-5632(00)01099-9
null
hep-ph
null
Most recent calculations of quarkonium production are based on the NRQCD factorization formalism. This formalism is reviewed. To make predictions about specific cross section, universal NRQCD matrix elements need to be extracted from experiments. Extractions from different experimental situations are compared, with some emphasis on the extraction from LEP.
[ { "created": "Tue, 22 Aug 2000 18:11:43 GMT", "version": "v1" } ]
2009-10-31
[ [ "Leibovich", "Adam K", "" ] ]
Most recent calculations of quarkonium production are based on the NRQCD factorization formalism. This formalism is reviewed. To make predictions about specific cross section, universal NRQCD matrix elements need to be extracted from experiments. Extractions from different experimental situations are compared, with some emphasis on the extraction from LEP.
1310.7471
Jianhui Zhang
Xiaonu Xiong, Xiangdong Ji, Jian-Hui Zhang, Yong Zhao
One-Loop Matching for Parton Distributions: Non-Singlet Case
10 pages, 1 figure
Phys. Rev. D 90, 014051 (2014)
10.1103/PhysRevD.90.014051
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive one-loop matching condition for non-singlet quark distributions in transverse-momentum cut-off scheme, including unpolarized, helicity and transversity distributions. The matching is between the quasi-distribution defined by static correlation at finite nucleon momentum and the light-cone distribution measurable in experiments. The result is useful for extracting the latter from the former in a lattice QCD calculation.
[ { "created": "Mon, 28 Oct 2013 15:59:23 GMT", "version": "v1" } ]
2014-08-13
[ [ "Xiong", "Xiaonu", "" ], [ "Ji", "Xiangdong", "" ], [ "Zhang", "Jian-Hui", "" ], [ "Zhao", "Yong", "" ] ]
We derive one-loop matching condition for non-singlet quark distributions in transverse-momentum cut-off scheme, including unpolarized, helicity and transversity distributions. The matching is between the quasi-distribution defined by static correlation at finite nucleon momentum and the light-cone distribution measurable in experiments. The result is useful for extracting the latter from the former in a lattice QCD calculation.
0905.2596
Alexey Gulov
A.V.Gulov and V.V.Skalozub
Model independent search for Z'-boson signals
60 pages, 14 figures. Minor corrections in the text
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An approach to the model-independent searching for the Z' gauge boson as a virtual state in scattering processes is developed. It accounts for as a basic requirement the renormalizability of underlying unspecified in other respects model. This results in a set of relations between low energy couplings of Z' to fermions that reduces in an essential way the number of parameters to be fitted in experiments. On this ground the observables which uniquely pick out the Z' boson in leptonic processes are introduced and the data of LEP experiments analyzed. The Z' couplings to leptons and quarks are estimated at 95% confidence level. These estimates may serve as a guide for experiments at the Tevatron and/or LHC. A comparison with other approaches and results is given.
[ { "created": "Fri, 15 May 2009 18:21:41 GMT", "version": "v1" }, { "created": "Mon, 22 Jun 2009 06:08:29 GMT", "version": "v2" } ]
2009-06-22
[ [ "Gulov", "A. V.", "" ], [ "Skalozub", "V. V.", "" ] ]
An approach to the model-independent searching for the Z' gauge boson as a virtual state in scattering processes is developed. It accounts for as a basic requirement the renormalizability of underlying unspecified in other respects model. This results in a set of relations between low energy couplings of Z' to fermions that reduces in an essential way the number of parameters to be fitted in experiments. On this ground the observables which uniquely pick out the Z' boson in leptonic processes are introduced and the data of LEP experiments analyzed. The Z' couplings to leptons and quarks are estimated at 95% confidence level. These estimates may serve as a guide for experiments at the Tevatron and/or LHC. A comparison with other approaches and results is given.
hep-ph/0409074
Maurizio Piai
Maurizio Piai
Composite Vector Mesons and the Little Higgs Mechanism
4 pages, 2 figures, Talk given at the 12th International Conference on Supersymmetry and Unification of Fundamental Interactions, June 17-23, 2004, Tsukuba, Japan
null
null
null
hep-ph
null
I review a technique to embed vector mesons in the chiral Lagrangian of QCD, and apply it to more general coset spaces, relevant for Little Higgs models. The implementation of heavy spin-1 fields in Little Higgs models allows for a better control over previously non calculable, ultra-violate sensitive quantities, such as the Higgs couplings. A relevant application is the study of vacuum alignment in the SU(6)/Sp(6) models.
[ { "created": "Tue, 7 Sep 2004 14:44:00 GMT", "version": "v1" } ]
2007-05-23
[ [ "Piai", "Maurizio", "" ] ]
I review a technique to embed vector mesons in the chiral Lagrangian of QCD, and apply it to more general coset spaces, relevant for Little Higgs models. The implementation of heavy spin-1 fields in Little Higgs models allows for a better control over previously non calculable, ultra-violate sensitive quantities, such as the Higgs couplings. A relevant application is the study of vacuum alignment in the SU(6)/Sp(6) models.
1910.09640
Umberto D'Alesio
Umberto D'Alesio, Francesco Murgia, Cristian Pisano, and Sangem Rajesh
Single-spin asymmetries in $p^\uparrow p \to J/\psi +X$ within a TMD approach: role of the color octet mechanism
10 pages, 6 figures (12 plots)
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the transverse single-spin asymmetry (SSA) for $J/\psi$ production in proton-proton collisions, within non-relativistic QCD, employing the transverse momentum dependent, generalized parton model, which includes both spin and intrinsic motion effects. In particular, we study the role of the color octet mechanism in accessing the gluon Sivers function. In doing that, we also show, within this approach, how the singularities coming from color octet terms in the low-$P_T$ region can be handled, leading to finite cross sections. Predictions for both unpolarized cross sections and SSAs are given and compared against PHENIX data. Estimates for LHCb in the fixed target mode are also presented.
[ { "created": "Mon, 21 Oct 2019 20:38:20 GMT", "version": "v1" } ]
2019-10-23
[ [ "D'Alesio", "Umberto", "" ], [ "Murgia", "Francesco", "" ], [ "Pisano", "Cristian", "" ], [ "Rajesh", "Sangem", "" ] ]
We calculate the transverse single-spin asymmetry (SSA) for $J/\psi$ production in proton-proton collisions, within non-relativistic QCD, employing the transverse momentum dependent, generalized parton model, which includes both spin and intrinsic motion effects. In particular, we study the role of the color octet mechanism in accessing the gluon Sivers function. In doing that, we also show, within this approach, how the singularities coming from color octet terms in the low-$P_T$ region can be handled, leading to finite cross sections. Predictions for both unpolarized cross sections and SSAs are given and compared against PHENIX data. Estimates for LHCb in the fixed target mode are also presented.
1405.0938
Marlene Nahrgang
Marlene Nahrgang, J\"org Aichelin, Pol Bernard Gossiaux, Klaus Werner
D mesons in non-central heavy-ion collisions: fluctuating vs. averaged initial conditions
Contribution to the Hard Probes 2013 Conference
null
10.1016/j.nuclphysa.2014.07.017
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The suppression of D mesons in non-central heavy-ion collisions is investigated. The anisotropy in collisions at finite impact parameter leads to an ordering of all-angle, in- and out-of-plane nuclear modification factors due to the different in-medium path lengths. Within our MC@sHQ+EPOS model of heavy-quark propagation in the QGP we demonstrate that fluctuating initial conditions lead to an effective reduction of the energy loss of heavy quarks, which is seen in a larger nuclear modification factor at intermediate and high transverse momenta. The elliptic flow at small transverse momenta is reduced.
[ { "created": "Mon, 5 May 2014 15:55:04 GMT", "version": "v1" } ]
2015-10-28
[ [ "Nahrgang", "Marlene", "" ], [ "Aichelin", "Jörg", "" ], [ "Gossiaux", "Pol Bernard", "" ], [ "Werner", "Klaus", "" ] ]
The suppression of D mesons in non-central heavy-ion collisions is investigated. The anisotropy in collisions at finite impact parameter leads to an ordering of all-angle, in- and out-of-plane nuclear modification factors due to the different in-medium path lengths. Within our MC@sHQ+EPOS model of heavy-quark propagation in the QGP we demonstrate that fluctuating initial conditions lead to an effective reduction of the energy loss of heavy quarks, which is seen in a larger nuclear modification factor at intermediate and high transverse momenta. The elliptic flow at small transverse momenta is reduced.
0909.2498
Wojciech Krolikowski
Wojciech Krolikowski (University of Warsaw)
Is the electromagnetic field a source of a mediating field in hidden sector?
1+9 pages, two unpleasant misprints are corrected
null
null
IFT-09/9
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We continue the discussion of a proposed model of hidden sector of the Universe, consisting of sterile spin-1/2 Dirac fermions ("sterinos"), sterile spin-0 bosons ("sterons") with spontaneously nonzero vacuum expectation value, and sterile nongauge mediating bosons ("A bosons") described by an antisymmetric-tensor field (of dimension one). The Standard-Model electromagnetic field (of dimension two) multiplied by the steron vacuum expectation value becomes in a spontaneous way a source of A-boson field mediating new weak interactions in hidden sector and providing - due to the action of electromagnetic field in both sectors - a weak coupling between hidden and Standard-Model sectors ("photonic portal"). The proposed photonic portal emphasizes even more the role of electromagnetic field in the structure of the Universe.
[ { "created": "Mon, 14 Sep 2009 09:42:25 GMT", "version": "v1" }, { "created": "Wed, 9 Dec 2009 10:15:01 GMT", "version": "v2" } ]
2009-12-09
[ [ "Krolikowski", "Wojciech", "", "University of Warsaw" ] ]
We continue the discussion of a proposed model of hidden sector of the Universe, consisting of sterile spin-1/2 Dirac fermions ("sterinos"), sterile spin-0 bosons ("sterons") with spontaneously nonzero vacuum expectation value, and sterile nongauge mediating bosons ("A bosons") described by an antisymmetric-tensor field (of dimension one). The Standard-Model electromagnetic field (of dimension two) multiplied by the steron vacuum expectation value becomes in a spontaneous way a source of A-boson field mediating new weak interactions in hidden sector and providing - due to the action of electromagnetic field in both sectors - a weak coupling between hidden and Standard-Model sectors ("photonic portal"). The proposed photonic portal emphasizes even more the role of electromagnetic field in the structure of the Universe.