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1412.1108
Toru Kojo
Toru Kojo, Philip D. Powell, Yifan Song, Gordon Baym
Phenomenological QCD equation of state for massive neutron stars
14 pages, 14 figures; v2 published version in PRD
Phys. Rev. D 91, 045003 (2015)
10.1103/PhysRevD.91.045003
null
hep-ph astro-ph.SR hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We construct an equation of state for massive neutron stars based on quantum chromodynamics phenomenology. Our primary purpose is to delineate the relevant ingredients of equations of state that simultaneously have the required stiffness and satisfy constraints from thermodynamics and causality. These ingredients are: (i) a repulsive density-density interaction, universal for all flavors; (ii) the color-magnetic interaction active from low to high densities; (iii) confining effects, which become increasingly important as the baryon density decreases; (iv) non-perturbative gluons, which are not very sensitive to changes of the quark density. We use the following "3-window" description: At baryon densities below about twice normal nuclear density, 2n_0, we use the Akmal-Pandharipande-Ravenhall (APR) equation of state, and at high densities, > (4-7)n_0, we use the three-flavor Nambu-Jona-Lasinio (NJL) model supplemented by vector and diquark interactions. In the transition density region, we smoothly interpolate the hadronic and quark equations of state in the chemical potential-pressure plane. Requiring that the equation of state approach APR at low densities, we find that the quark pressure in non-confining models can be larger than the hadronic pressure, unlike in conventional equations of state. We show that consistent equations of state of stiffness sufficient to allow massive neutron stars are reasonably tightly constrained, suggesting that gluon dynamics remains non-perturbative even at baryon densities ~10n_0.
[ { "created": "Tue, 2 Dec 2014 21:33:56 GMT", "version": "v1" }, { "created": "Mon, 19 Jan 2015 17:59:29 GMT", "version": "v2" } ]
2015-03-05
[ [ "Kojo", "Toru", "" ], [ "Powell", "Philip D.", "" ], [ "Song", "Yifan", "" ], [ "Baym", "Gordon", "" ] ]
We construct an equation of state for massive neutron stars based on quantum chromodynamics phenomenology. Our primary purpose is to delineate the relevant ingredients of equations of state that simultaneously have the required stiffness and satisfy constraints from thermodynamics and causality. These ingredients are: (i) a repulsive density-density interaction, universal for all flavors; (ii) the color-magnetic interaction active from low to high densities; (iii) confining effects, which become increasingly important as the baryon density decreases; (iv) non-perturbative gluons, which are not very sensitive to changes of the quark density. We use the following "3-window" description: At baryon densities below about twice normal nuclear density, 2n_0, we use the Akmal-Pandharipande-Ravenhall (APR) equation of state, and at high densities, > (4-7)n_0, we use the three-flavor Nambu-Jona-Lasinio (NJL) model supplemented by vector and diquark interactions. In the transition density region, we smoothly interpolate the hadronic and quark equations of state in the chemical potential-pressure plane. Requiring that the equation of state approach APR at low densities, we find that the quark pressure in non-confining models can be larger than the hadronic pressure, unlike in conventional equations of state. We show that consistent equations of state of stiffness sufficient to allow massive neutron stars are reasonably tightly constrained, suggesting that gluon dynamics remains non-perturbative even at baryon densities ~10n_0.
2311.18811
Michel Stillger
Philipp B\"oer, Patrick Hager, Matthias Neubert, Michel Stillger, Xiaofeng Xu (JGU Mainz)
Glauber Phases in Non-Global LHC Observables: Resummation for Gluon-Initiated Processes
38 pages, 5 figures
null
null
MITP-23-064
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The resummation of the ''Glauber series'' in non-global LHC observables is extended to processes with gluons in the initial state. This series simultaneously incorporates large double-logarithmic corrections, the so-called ''super-leading logarithms'', together with higher-order exchanges of pairs of Glauber gluons associated with the large numerical factor $(i\pi)^2$. On a technical level, the main part of this work is devoted to the systematic reduction of the appearing color traces and construction of basis structures, which consist of thirteen elements for $gg$ and eleven elements for $qg$ scattering. Numerical estimates for wide-angle gap-between-jet cross sections at the parton level show that, in particular for $gg$ scattering at relatively small vetoes $Q_0$, the contribution involving four Glauber exchanges gives a sizeable correction and should not be neglected.
[ { "created": "Thu, 30 Nov 2023 18:52:53 GMT", "version": "v1" } ]
2023-12-01
[ [ "Böer", "Philipp", "", "JGU Mainz" ], [ "Hager", "Patrick", "", "JGU Mainz" ], [ "Neubert", "Matthias", "", "JGU Mainz" ], [ "Stillger", "Michel", "", "JGU Mainz" ], [ "Xu", "Xiaofeng", "", "JGU Mainz" ] ]
The resummation of the ''Glauber series'' in non-global LHC observables is extended to processes with gluons in the initial state. This series simultaneously incorporates large double-logarithmic corrections, the so-called ''super-leading logarithms'', together with higher-order exchanges of pairs of Glauber gluons associated with the large numerical factor $(i\pi)^2$. On a technical level, the main part of this work is devoted to the systematic reduction of the appearing color traces and construction of basis structures, which consist of thirteen elements for $gg$ and eleven elements for $qg$ scattering. Numerical estimates for wide-angle gap-between-jet cross sections at the parton level show that, in particular for $gg$ scattering at relatively small vetoes $Q_0$, the contribution involving four Glauber exchanges gives a sizeable correction and should not be neglected.
1806.03358
Sony Martins
M. B. Gay Ducati and S. Martins
Exclusive Photoproduction $J/\psi$ in Peripheral Pb-Pb
Poster presented at the XIV International Workshop on Hadron Physics, Florian\'opolis, Brazil, March 2018
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The exclusive photoproduction of the $J/\psi$ state is investigated in peripheral AA collisions for the energies available at the LHC, $\sqrt{s}=2.76$ TeV and $\sqrt{s}=5.02$ TeV. In order to evaluate the robustness of the light-cone color dipole formalism, previously tested in the ultraperipheral regime, the rapidity distribution and the nuclear modification factor ($R_{AA}$) were calculated for three centrality classes: 30%-50%, 50%-70% and 70%-90%. In the peripheral regime, three scenarios were considered. In the scenario 1, a similar formalism adopted in the UPC regime is used; in the scenario 2, one considers that only the spectators in the target are the ones that interact coherently with the photon; in the scenario 3, the photonuclear cross section is modified using the same geometrical constraints applyed in the scenario 2. The results obtained from the three scenarios were compared with the ALICE measurements (only $J/\psi$ at the moment), showing a better agreement in the more complete approach (scenario 3), mainly in the more central regions (30%-50% and 50%-70%) where the incertainty is smaller.
[ { "created": "Fri, 8 Jun 2018 21:25:27 GMT", "version": "v1" } ]
2018-06-12
[ [ "Ducati", "M. B. Gay", "" ], [ "Martins", "S.", "" ] ]
The exclusive photoproduction of the $J/\psi$ state is investigated in peripheral AA collisions for the energies available at the LHC, $\sqrt{s}=2.76$ TeV and $\sqrt{s}=5.02$ TeV. In order to evaluate the robustness of the light-cone color dipole formalism, previously tested in the ultraperipheral regime, the rapidity distribution and the nuclear modification factor ($R_{AA}$) were calculated for three centrality classes: 30%-50%, 50%-70% and 70%-90%. In the peripheral regime, three scenarios were considered. In the scenario 1, a similar formalism adopted in the UPC regime is used; in the scenario 2, one considers that only the spectators in the target are the ones that interact coherently with the photon; in the scenario 3, the photonuclear cross section is modified using the same geometrical constraints applyed in the scenario 2. The results obtained from the three scenarios were compared with the ALICE measurements (only $J/\psi$ at the moment), showing a better agreement in the more complete approach (scenario 3), mainly in the more central regions (30%-50% and 50%-70%) where the incertainty is smaller.
hep-ph/9808461
Giorgio Papini
C.X. Chen, G. Papini, N. Mobed and G. Lambiase, G. Scarpetta
Maximal Acceleration Corrections to the Lamb Shift of Muonic Hydrogen
LaTex file, 9 pages, to be published in Il Nuovo Cimento B
Nuovo Cim. B114 (1999) 199-205
null
null
hep-ph
null
The maximal acceleration corrections to the Lamb shift of muonic hydrogen are calculated by using the relativistic Dirac wave functions. The correction for the $2S-2P$ transition is $\sim 0.38$ meV and is higher than the accuracy of present QED calculations and of the expected accuracy of experiments in preparation.
[ { "created": "Fri, 28 Aug 1998 16:21:32 GMT", "version": "v1" } ]
2007-05-23
[ [ "Chen", "C. X.", "" ], [ "Papini", "G.", "" ], [ "Mobed", "N.", "" ], [ "Lambiase", "G.", "" ], [ "Scarpetta", "G.", "" ] ]
The maximal acceleration corrections to the Lamb shift of muonic hydrogen are calculated by using the relativistic Dirac wave functions. The correction for the $2S-2P$ transition is $\sim 0.38$ meV and is higher than the accuracy of present QED calculations and of the expected accuracy of experiments in preparation.
2302.14200
Mohsen Khodadi
Mohsen Khodadi, Gaetano Lambiase and Leonardo Mastrototaro
Spontaneous Lorentz symmetry breaking effects on GRBs jets arising from neutrino pair annihilation process near a black hole
12 pages (two columns), 4 figures, 1 table, accepted for publication in EPJC
Eur.Phys.J.C (2023) 83:239
10.1140/epjc/s10052-023-11369-2
null
hep-ph astro-ph.HE gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study of neutrino pair annihilation into electron-positron pairs ($\nu{\bar \nu}\to e^-e^+$) is astrophysically well-motivated because it is a possible powering mechanism for the gamma-ray bursts (GRBs). In this paper, we estimate the gamma-ray energy deposition rate (EDR) arising from the annihilation of the neutrino pairs in the equatorial plane of a slowly rotating black hole geometry modified by the broken Lorentz symmetry (induced by a background bumblebee vector field). More specifically, owing to the presence of a dimensionless Lorentz symmetry breaking (LSB) parameter $l$ arising from nonminimal coupling between the bumblebee field with nonzero vacuum expectation value and gravity, the metric solution in question differs from the standard slowly rotating Kerr black hole. By idealizing the thin accretion disk temperature profile in the two forms of isothermal and gradient around the bumblebee gravity-based slow rotating black hole, we investigate the influence of spontaneous LSB on the $\nu{\bar \nu}$-annihilation efficiency. For both profiles, we find that positive values of LSB parameter $l>0$ induce an enhancement of the EDR associated with the neutrino-antineutrino annihilation. Therefore, the process of powering the GRBs jets around bumblebee gravity modified slowly rotating geometry is more efficient in comparison with standard metric. Using the observed gamma-ray luminosity associated with different GRBs types (short, long, and ultra-long), we find, through the analysis of the EDR in the parameter space $l-a$ ($a^2\ll1$), some allowed ranges for the LSB parameter $l$.
[ { "created": "Mon, 27 Feb 2023 23:35:41 GMT", "version": "v1" }, { "created": "Wed, 22 Mar 2023 10:48:11 GMT", "version": "v2" } ]
2023-03-23
[ [ "Khodadi", "Mohsen", "" ], [ "Lambiase", "Gaetano", "" ], [ "Mastrototaro", "Leonardo", "" ] ]
The study of neutrino pair annihilation into electron-positron pairs ($\nu{\bar \nu}\to e^-e^+$) is astrophysically well-motivated because it is a possible powering mechanism for the gamma-ray bursts (GRBs). In this paper, we estimate the gamma-ray energy deposition rate (EDR) arising from the annihilation of the neutrino pairs in the equatorial plane of a slowly rotating black hole geometry modified by the broken Lorentz symmetry (induced by a background bumblebee vector field). More specifically, owing to the presence of a dimensionless Lorentz symmetry breaking (LSB) parameter $l$ arising from nonminimal coupling between the bumblebee field with nonzero vacuum expectation value and gravity, the metric solution in question differs from the standard slowly rotating Kerr black hole. By idealizing the thin accretion disk temperature profile in the two forms of isothermal and gradient around the bumblebee gravity-based slow rotating black hole, we investigate the influence of spontaneous LSB on the $\nu{\bar \nu}$-annihilation efficiency. For both profiles, we find that positive values of LSB parameter $l>0$ induce an enhancement of the EDR associated with the neutrino-antineutrino annihilation. Therefore, the process of powering the GRBs jets around bumblebee gravity modified slowly rotating geometry is more efficient in comparison with standard metric. Using the observed gamma-ray luminosity associated with different GRBs types (short, long, and ultra-long), we find, through the analysis of the EDR in the parameter space $l-a$ ($a^2\ll1$), some allowed ranges for the LSB parameter $l$.
1004.4368
Eef van Beveren
Eef van Beveren and George Rupp
Evidence for further charmonium vector resonances
5 pages, 5 figures
Chinese Physics C35, 319-324 (2011)
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the shape of threshold signals in production cross sections of the reaction e+ + e- --> D* + antiD*, at the opening of the D(s)* antiD(s)* and Lambda(c)+ Lambda(c)- channels. Furthermore, evidence for the 3D, 5S, 4D, 6S, 5D, 7S, 6D, and 8S charmonium vector resonances is presented, on the basis of data recently published by the BaBar Collaboration. Central masses and resonance widths are estimated. Confirmation of these resonances would be a huge step in lifting the precision level of hadron spectroscopy towards that of atomic spectroscopy, with far-reaching consequences for theory.
[ { "created": "Sun, 25 Apr 2010 17:54:26 GMT", "version": "v1" } ]
2011-03-16
[ [ "van Beveren", "Eef", "" ], [ "Rupp", "George", "" ] ]
We discuss the shape of threshold signals in production cross sections of the reaction e+ + e- --> D* + antiD*, at the opening of the D(s)* antiD(s)* and Lambda(c)+ Lambda(c)- channels. Furthermore, evidence for the 3D, 5S, 4D, 6S, 5D, 7S, 6D, and 8S charmonium vector resonances is presented, on the basis of data recently published by the BaBar Collaboration. Central masses and resonance widths are estimated. Confirmation of these resonances would be a huge step in lifting the precision level of hadron spectroscopy towards that of atomic spectroscopy, with far-reaching consequences for theory.
1306.2703
Stefan H\"oche
Stefan Hoeche, Junwu Huang, Gionata Luisoni, Marek Schoenherr, Jan Winter
Zero and one jet combined NLO analysis of the top quark forward-backward asymmetry
16 pages, 2 tables, 3 figures
null
10.1103/PhysRevD.88.014040
SLAC-PUB 15553, MPP-2013-154, IPPP/13/39, DCPT/13/78, MCNET/13/07, LPN13-035
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present an analysis of the forward-backward asymmetry in the production of top quark pairs at the Tevatron collider. We use novel Monte Carlo methods for merging matrix elements and parton showers to combine NLO QCD predictions for tt and tt+jet production. Theoretical uncertainties are quantified in detail. We find agreement with experimental data on the transverse momentum dependence of the asymmetry.
[ { "created": "Wed, 12 Jun 2013 03:39:40 GMT", "version": "v1" }, { "created": "Wed, 17 Jul 2013 07:50:24 GMT", "version": "v2" } ]
2013-08-09
[ [ "Hoeche", "Stefan", "" ], [ "Huang", "Junwu", "" ], [ "Luisoni", "Gionata", "" ], [ "Schoenherr", "Marek", "" ], [ "Winter", "Jan", "" ] ]
We present an analysis of the forward-backward asymmetry in the production of top quark pairs at the Tevatron collider. We use novel Monte Carlo methods for merging matrix elements and parton showers to combine NLO QCD predictions for tt and tt+jet production. Theoretical uncertainties are quantified in detail. We find agreement with experimental data on the transverse momentum dependence of the asymmetry.
hep-ph/0104045
Jose Maria Martinez Resco
J.M. Martinez Resco, M.A. Valle Basagoiti
Matter-induced vertices for photon splitting in a weakly magnetized plasma
14 pages, 1 figure. Accepted for publication in PRD
Phys.Rev. D64 (2001) 016006
10.1103/PhysRevD.64.016006
null
hep-ph
null
We evaluate the three-photon vertex functions at order $B$ and $B^{2}$ in a weak constant magnetic field at finite temperature and density with on shell external lines. Their application to the study of the photon splitting process leads to consider high energy photons whose dispersion relations are not changed significantly by the plasma effects. The absorption coefficient is computed and compared with the perturbative vacuum result. For the values of temperature and density of some astrophysical objects with a weak magnetic field, the matter effects are negligible.
[ { "created": "Wed, 4 Apr 2001 09:53:57 GMT", "version": "v1" } ]
2009-11-07
[ [ "Resco", "J. M. Martinez", "" ], [ "Basagoiti", "M. A. Valle", "" ] ]
We evaluate the three-photon vertex functions at order $B$ and $B^{2}$ in a weak constant magnetic field at finite temperature and density with on shell external lines. Their application to the study of the photon splitting process leads to consider high energy photons whose dispersion relations are not changed significantly by the plasma effects. The absorption coefficient is computed and compared with the perturbative vacuum result. For the values of temperature and density of some astrophysical objects with a weak magnetic field, the matter effects are negligible.
1711.00787
Matthias Jamin
Matthias Jamin and Ramon Miravitllas
Absence of even-integer $\zeta$-function values in Euclidean physical quantities in QCD
5 pages; 2 refs added, version published in Phys. Lett. B
Phys. Lett. B779 (2018) 452-455
10.1016/j.physletb.2018.02.030
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
At order $\alpha_s^4$ in perturbative quantum chromodynamics, even-integer $\zeta$-function values are present in Euclidean physical correlation functions like the scalar quark correlation function or the scalar gluonium correlator. We demonstrate that these contributions cancel when the perturbative expansion is expressed in terms of the so-called $C$-scheme coupling $\hat\alpha_s$ which has recently been introduced in Ref. [1]. It is furthermore conjectured that a $\zeta_4$ term should arise in the Adler function at order $\alpha_s^5$ in the $\overline{\rm MS}$-scheme, and that this term is expected to disappear in the $C$-scheme as well.
[ { "created": "Thu, 2 Nov 2017 15:43:51 GMT", "version": "v1" }, { "created": "Tue, 6 Mar 2018 07:03:15 GMT", "version": "v2" } ]
2018-03-07
[ [ "Jamin", "Matthias", "" ], [ "Miravitllas", "Ramon", "" ] ]
At order $\alpha_s^4$ in perturbative quantum chromodynamics, even-integer $\zeta$-function values are present in Euclidean physical correlation functions like the scalar quark correlation function or the scalar gluonium correlator. We demonstrate that these contributions cancel when the perturbative expansion is expressed in terms of the so-called $C$-scheme coupling $\hat\alpha_s$ which has recently been introduced in Ref. [1]. It is furthermore conjectured that a $\zeta_4$ term should arise in the Adler function at order $\alpha_s^5$ in the $\overline{\rm MS}$-scheme, and that this term is expected to disappear in the $C$-scheme as well.
hep-ph/9504328
Michael P. Mattis
Nick Dorey and Michael Mattis
The Large-N_c Renormalization Group
Talk presented at the 1995 Int'l Workshop on Nuclear & Particle Physics, Seoul, Korea. Accompanied by uu-compressed figures, automatically inserted into LaTeX file
null
null
null
hep-ph
null
In this talk we review how effective theories of mesons and baryons become exactly soluble in the large-N_c limit. We start with a generic hadron Lagrangian constrained only by certain well-known large-N_c selection rules. The bare vertices of the theory are dressed by an infinite class of UV divergent Feynman diagrams at leading order in 1/N_c. We show how all these leading-order diagrams can be summed exactly using semiclassical techniques. The saddle-point field configuration is reminiscent of the chiral bag: hedgehog pions outside a sphere of radius \Lambda^{-1} (\Lambda being the UV cutoff of the effective theory) matched onto nucleon degrees of freedom for r < \Lambda^{-1}. The effect of this pion cloud is to renormalize the bare nucleon mass, nucleon-\Delta hyperfine mass splitting, and Yukawa couplings of the theory. The corresponding large-N_c renormalization group equations for these parameters are presented, and solved explicitly in a series of simple models. We explain under what conditions the Skyrmion emerges as a UV fixed-point of the RG flow as \Lambda --> \infty.
[ { "created": "Tue, 18 Apr 1995 23:14:14 GMT", "version": "v1" } ]
2007-05-23
[ [ "Dorey", "Nick", "" ], [ "Mattis", "Michael", "" ] ]
In this talk we review how effective theories of mesons and baryons become exactly soluble in the large-N_c limit. We start with a generic hadron Lagrangian constrained only by certain well-known large-N_c selection rules. The bare vertices of the theory are dressed by an infinite class of UV divergent Feynman diagrams at leading order in 1/N_c. We show how all these leading-order diagrams can be summed exactly using semiclassical techniques. The saddle-point field configuration is reminiscent of the chiral bag: hedgehog pions outside a sphere of radius \Lambda^{-1} (\Lambda being the UV cutoff of the effective theory) matched onto nucleon degrees of freedom for r < \Lambda^{-1}. The effect of this pion cloud is to renormalize the bare nucleon mass, nucleon-\Delta hyperfine mass splitting, and Yukawa couplings of the theory. The corresponding large-N_c renormalization group equations for these parameters are presented, and solved explicitly in a series of simple models. We explain under what conditions the Skyrmion emerges as a UV fixed-point of the RG flow as \Lambda --> \infty.
2211.02028
Vedran Brdar
Vedran Brdar, Ying-Ying Li
Neutrino Origin of LHAASO's 18 TeV GRB221009A Photon
5 pages, 2 figures, published version
Phys. Lett. B 839 (2023) 137763
10.1016/j.physletb.2023.137763
USTC-ICTS/PCFT-22-30
hep-ph astro-ph.CO astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
LHAASO collaboration detected photons with energy above 10 TeV from the most recent gamma-ray burst (GRB), GRB221009A. Given the redshift of this event, $z\sim 0.15$, photons of such energy are expected to interact with the diffuse extragalactic background light (EBL) well before reaching Earth. In this paper we provide a novel neutrino-related explanation of the most energetic 18 TeV event reported by LHAASO. We find that the minimal viable scenario involves both mixing and transition magnetic moment portal between light and sterile neutrinos. The production of sterile neutrinos occurs efficiently via mixing while the transition magnetic moment portal governs the decay rate in the parameter space where tree-level decays via mixing to non-photon final states are suppressed. Our explanation of this event, while being consistent with the terrestrial constraints, points to the non-standard cosmology.
[ { "created": "Thu, 3 Nov 2022 17:47:24 GMT", "version": "v1" }, { "created": "Wed, 15 Feb 2023 13:52:37 GMT", "version": "v2" } ]
2023-02-16
[ [ "Brdar", "Vedran", "" ], [ "Li", "Ying-Ying", "" ] ]
LHAASO collaboration detected photons with energy above 10 TeV from the most recent gamma-ray burst (GRB), GRB221009A. Given the redshift of this event, $z\sim 0.15$, photons of such energy are expected to interact with the diffuse extragalactic background light (EBL) well before reaching Earth. In this paper we provide a novel neutrino-related explanation of the most energetic 18 TeV event reported by LHAASO. We find that the minimal viable scenario involves both mixing and transition magnetic moment portal between light and sterile neutrinos. The production of sterile neutrinos occurs efficiently via mixing while the transition magnetic moment portal governs the decay rate in the parameter space where tree-level decays via mixing to non-photon final states are suppressed. Our explanation of this event, while being consistent with the terrestrial constraints, points to the non-standard cosmology.
hep-ph/0608066
Gouranga Nayak
Gouranga C. Nayak (SUNY, Stony Brook), Jian-Wei Qiu (Iowa State U.), George Sterman (SUNY, Stony Brook)
NRQCD Factorization and Velocity-dependence of NNLO Poles in Heavy Quarkonium Production
23pages latex, 2 figures
Phys.Rev.D74:074007,2006
10.1103/PhysRevD.74.074007
YITP-SB-06-23
hep-ph hep-th nucl-th
null
We study the transition of a heavy quark pair from octet to singlet color configurations at next-to-next-to-leading order (NNLO) in heavy quarkonium production. We show that the infrared singularities in this process are consistent with NRQCD factorization to all orders in the heavy quark relative velocity v. This factorization requires the gauge-completed matrix elements that we introduced previously to prove NNLO factorization to order v ^2.
[ { "created": "Sat, 5 Aug 2006 17:40:03 GMT", "version": "v1" } ]
2008-11-26
[ [ "Nayak", "Gouranga C.", "", "SUNY, Stony Brook" ], [ "Qiu", "Jian-Wei", "", "Iowa State U." ], [ "Sterman", "George", "", "SUNY, Stony Brook" ] ]
We study the transition of a heavy quark pair from octet to singlet color configurations at next-to-next-to-leading order (NNLO) in heavy quarkonium production. We show that the infrared singularities in this process are consistent with NRQCD factorization to all orders in the heavy quark relative velocity v. This factorization requires the gauge-completed matrix elements that we introduced previously to prove NNLO factorization to order v ^2.
hep-ph/9605337
Dr. Ivica Picek
J.O. Eeg, K. Kumericki and I. Picek
On the dispersive two-photon K_L -> \mu^+ \mu^- amplitude
7 pages, 6 PS figures, uses psfig, revised version with important numerical error corrected, to appear in Z.f.Phys.C (and one additional reference)
Eur.Phys.J.C1:531-537,1998
10.1007/s100520050102
BI - TP 96/08, Oslo-TP-2-96 and ZTF - 96/03
hep-ph
null
We present a full account of the two-loop electroweak, two-photon mediated short-distance dispersive $K_L \to\mu^+\mu^-$ decay amplitude. QCD corrections change the sign of this amplitude and reduce it by an order of magnitude. Thus, the QCD-corrected two-loop amplitude represents only a small fraction (with the central value of 5 %) of the one-loop weak short-distance contribution, and has the same sign. In combination with a recent measurement, the standard-model prediction of the short-distance amplitude, completed in this paper, provides a constraint on the otherwise uncertain long-distance dispersive amplitude.
[ { "created": "Fri, 17 May 1996 09:59:25 GMT", "version": "v1" }, { "created": "Wed, 27 Aug 1997 12:29:37 GMT", "version": "v2" } ]
2011-09-13
[ [ "Eeg", "J. O.", "" ], [ "Kumericki", "K.", "" ], [ "Picek", "I.", "" ] ]
We present a full account of the two-loop electroweak, two-photon mediated short-distance dispersive $K_L \to\mu^+\mu^-$ decay amplitude. QCD corrections change the sign of this amplitude and reduce it by an order of magnitude. Thus, the QCD-corrected two-loop amplitude represents only a small fraction (with the central value of 5 %) of the one-loop weak short-distance contribution, and has the same sign. In combination with a recent measurement, the standard-model prediction of the short-distance amplitude, completed in this paper, provides a constraint on the otherwise uncertain long-distance dispersive amplitude.
1802.07237
Gauthier Durieux
J. A. Aguilar Saavedra, C. Degrande, G. Durieux, F. Maltoni, E. Vryonidou, C. Zhang (editors), D. Barducci, I. Brivio, V. Cirigliano, W. Dekens, J. de Vries, C. Englert, M. Fabbrichesi, C. Grojean, U. Haisch, Y. Jiang, J. Kamenik, M. Mangano, D. Marzocca, E. Mereghetti, K. Mimasu, L. Moore, G. Perez, T. Plehn, F. Riva, M. Russell, J. Santiago, M. Schulze, Y. Soreq, A. Tonero, M. Trott, S. Westhoff, C. White, A. Wulzer, J. Zupan
Interpreting top-quark LHC measurements in the standard-model effective field theory
LHC TOP WG note, 10 pages of main text, 5 appendices, 1 figure, 21 tables
null
null
CERN-LPCC-2018-01
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
This note proposes common standards and prescriptions for the effective-field-theory interpretation of top-quark measurements at the LHC.
[ { "created": "Tue, 20 Feb 2018 18:31:50 GMT", "version": "v1" } ]
2018-02-21
[ [ "Saavedra", "J. A. Aguilar", "", "editors" ], [ "Degrande", "C.", "", "editors" ], [ "Durieux", "G.", "", "editors" ], [ "Maltoni", "F.", "", "editors" ], [ "Vryonidou", "E.", "", "editors" ], [ "Zhang", "C.", "", "editors" ], [ "Barducci", "D.", "" ], [ "Brivio", "I.", "" ], [ "Cirigliano", "V.", "" ], [ "Dekens", "W.", "" ], [ "de Vries", "J.", "" ], [ "Englert", "C.", "" ], [ "Fabbrichesi", "M.", "" ], [ "Grojean", "C.", "" ], [ "Haisch", "U.", "" ], [ "Jiang", "Y.", "" ], [ "Kamenik", "J.", "" ], [ "Mangano", "M.", "" ], [ "Marzocca", "D.", "" ], [ "Mereghetti", "E.", "" ], [ "Mimasu", "K.", "" ], [ "Moore", "L.", "" ], [ "Perez", "G.", "" ], [ "Plehn", "T.", "" ], [ "Riva", "F.", "" ], [ "Russell", "M.", "" ], [ "Santiago", "J.", "" ], [ "Schulze", "M.", "" ], [ "Soreq", "Y.", "" ], [ "Tonero", "A.", "" ], [ "Trott", "M.", "" ], [ "Westhoff", "S.", "" ], [ "White", "C.", "" ], [ "Wulzer", "A.", "" ], [ "Zupan", "J.", "" ] ]
This note proposes common standards and prescriptions for the effective-field-theory interpretation of top-quark measurements at the LHC.
hep-ph/0009119
Klaus Werner
G. Bossard, H.J. Drescher, N.N. Kalmykov, S. Ostapchenko, A.I. Pavlov, T. Pierog, E.A. Vishnevskaya, K. Werner
Cosmic Ray Air Shower Characteristics in the Framework of the Parton-Based Gribov-Regge Model NEXUS
15 pages, 8 figures
Phys.Rev. D63 (2001) 054030
10.1103/PhysRevD.63.054030
SUBATECH 00-13
hep-ph astro-ph nucl-th
null
The purpose of this paper is twofold: first we want to introduce a new type of hadronic interaction model (NEXUS), which has a much more solid theoretical basis as, for example, presently used models like QGSJET and VENUS, and ensures therefore a much more reliable extrapolation towards high energies. Secondly, we want to promote an extensive air shower (EAS) calculation scheme, based on cascade equations rather than explicit Monte Carlo simulations, which is very accurate in calculations of main EAS characteristics and extremely fast concerning computing time. We employ the NEXUS model to provide the necessary data on particle production in hadron-air collisions and present the average EAS characteristics for energies 10^14 - 10^17 eV. The experimental data of the casa-blanka group are analyzed in the framework of the new model.
[ { "created": "Mon, 11 Sep 2000 12:09:03 GMT", "version": "v1" } ]
2009-10-31
[ [ "Bossard", "G.", "" ], [ "Drescher", "H. J.", "" ], [ "Kalmykov", "N. N.", "" ], [ "Ostapchenko", "S.", "" ], [ "Pavlov", "A. I.", "" ], [ "Pierog", "T.", "" ], [ "Vishnevskaya", "E. A.", "" ], [ "Werner", "K.", "" ] ]
The purpose of this paper is twofold: first we want to introduce a new type of hadronic interaction model (NEXUS), which has a much more solid theoretical basis as, for example, presently used models like QGSJET and VENUS, and ensures therefore a much more reliable extrapolation towards high energies. Secondly, we want to promote an extensive air shower (EAS) calculation scheme, based on cascade equations rather than explicit Monte Carlo simulations, which is very accurate in calculations of main EAS characteristics and extremely fast concerning computing time. We employ the NEXUS model to provide the necessary data on particle production in hadron-air collisions and present the average EAS characteristics for energies 10^14 - 10^17 eV. The experimental data of the casa-blanka group are analyzed in the framework of the new model.
hep-ph/0209368
Thomas Schwetz
M. Maltoni, T. Schwetz, M.A. Tortola, J.W.F. Valle
Global analysis of neutrino oscillation data in four-neutrino schemes
5 pages, 4 figures, Talk by T. Schwetz at XXX Int. Meeting on Fundamental Physics, Jaca, Spain, 28 Jan-1 Feb 2002
Nucl.Phys.Proc.Suppl.114:203-207,2003
10.1016/S0920-5632(02)01906-0
UWThPh-2002-29
hep-ph
null
We present an analysis of the global neutrino oscillation data in terms of four-neutrino mass schemes. We find that the strong preference of oscillations into active neutrinos implied by the latest solar as well as atmospheric neutrino data allows to rule out (2+2) mass schemes, whereas (3+1) schemes are strongly disfavoured by short-baseline experiments. Our analysis shows that four-neutrino oscillations do not provide a satisfactory description of the global neutrino oscillation data including the LSND result.
[ { "created": "Mon, 30 Sep 2002 13:17:09 GMT", "version": "v1" } ]
2009-09-17
[ [ "Maltoni", "M.", "" ], [ "Schwetz", "T.", "" ], [ "Tortola", "M. A.", "" ], [ "Valle", "J. W. F.", "" ] ]
We present an analysis of the global neutrino oscillation data in terms of four-neutrino mass schemes. We find that the strong preference of oscillations into active neutrinos implied by the latest solar as well as atmospheric neutrino data allows to rule out (2+2) mass schemes, whereas (3+1) schemes are strongly disfavoured by short-baseline experiments. Our analysis shows that four-neutrino oscillations do not provide a satisfactory description of the global neutrino oscillation data including the LSND result.
2401.05258
Siyuan Li
D. Harnett, Siyuan Li, T.G. Steele
Numerically Computing Finite Temperature Loop Integrals using pySecDec
16 pages, 9 figures
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Finite-temperature quantum field theory provides the foundation for many important phenomena in the Standard Model and extensions, including phase transitions, baryogenesis, and gravitational waves. Methods are developed to enable application of pySecDec (a Python-language-based package designed for numerical calculation of dimensionally-regulated loop integrals) to numerically evaluate finite-temperature loop integrals in the imaginary time (Matsubara) formalism. These methods consist of two main elements: an inverse Wick rotation that converts a finite-temperature loop integral into a form applicable to pySecDec, and asymptotic techniques to regulate and accelerate convergence of the Matsubara frequency summations. Numerical pySecDec evaluation of finite-temperature, two-point and three-point, one-loop topologies for scalar fields is used to illustrate and validate these new methodologies. Advantages of these finite-temperature pySecDec numerical methods are illustrated by the inclusion of multiple mass and external momentum scales.
[ { "created": "Wed, 10 Jan 2024 16:37:12 GMT", "version": "v1" } ]
2024-01-11
[ [ "Harnett", "D.", "" ], [ "Li", "Siyuan", "" ], [ "Steele", "T. G.", "" ] ]
Finite-temperature quantum field theory provides the foundation for many important phenomena in the Standard Model and extensions, including phase transitions, baryogenesis, and gravitational waves. Methods are developed to enable application of pySecDec (a Python-language-based package designed for numerical calculation of dimensionally-regulated loop integrals) to numerically evaluate finite-temperature loop integrals in the imaginary time (Matsubara) formalism. These methods consist of two main elements: an inverse Wick rotation that converts a finite-temperature loop integral into a form applicable to pySecDec, and asymptotic techniques to regulate and accelerate convergence of the Matsubara frequency summations. Numerical pySecDec evaluation of finite-temperature, two-point and three-point, one-loop topologies for scalar fields is used to illustrate and validate these new methodologies. Advantages of these finite-temperature pySecDec numerical methods are illustrated by the inclusion of multiple mass and external momentum scales.
0901.0720
Jing Shu
Seong Chan Park, Jing Shu
Split-UED and Dark Matter
4 pages, 3 figures, 1 table
Phys.Rev.D79:091702,2009
10.1103/PhysRevD.79.091702
IPMU 09-0003
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the recent observation of the high energy electron and positron excesses in cosmic ray by PAMELA and ATIC/PPB-BETS, we suggest an anomaly-free scenario for the universal extra dimension that localizes the SM quarks and splits the spectrum of KK quarks from KK leptons. When the SM quarks are "well localized" at the boundaries, the most stringent bound of the model ($1/R > 510$ GeV) comes from the resonance search for the Tevatron dijet channels. Even at the early stage of LHC, one can discover the second KK gluon for masses up to 4 TeV.
[ { "created": "Wed, 7 Jan 2009 11:55:42 GMT", "version": "v1" }, { "created": "Tue, 12 May 2009 13:22:35 GMT", "version": "v2" } ]
2010-04-14
[ [ "Park", "Seong Chan", "" ], [ "Shu", "Jing", "" ] ]
Motivated by the recent observation of the high energy electron and positron excesses in cosmic ray by PAMELA and ATIC/PPB-BETS, we suggest an anomaly-free scenario for the universal extra dimension that localizes the SM quarks and splits the spectrum of KK quarks from KK leptons. When the SM quarks are "well localized" at the boundaries, the most stringent bound of the model ($1/R > 510$ GeV) comes from the resonance search for the Tevatron dijet channels. Even at the early stage of LHC, one can discover the second KK gluon for masses up to 4 TeV.
2101.08916
Yalu Hu
YaLu Hu, ChuanLe Sun, Xiao-Min Shen, Jun Gao
Hadronic decays of Higgs boson at NNLO matched with parton shower
28 pages, 12 figures; published version
null
10.1007/JHEP08(2021)122
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present predictions for hadronic decays of the Higgs boson at next-to-next-to-leading order (NNLO) in QCD matched with parton shower based on the POWHEG framework. Those include decays into bottom quarks with full bottom-quark mass dependence, light quarks, and gluons in the heavy top quark effective theory. Our calculations describe exclusive decays of the Higgs boson with leading logarithmic accuracy in the Sudakov region and next-to-leading order (NLO) accuracy matched with parton shower in the three-jet region, with normalizations fixed to the partial width at NNLO. We estimated remaining perturbative uncertainties taking typical event shape variables as an example and demonstrated the need of future improvements on both parton shower and matrix element calculations. The calculations can be used immediately in evaluations of the physics performances of detector designs for future Higgs factories.
[ { "created": "Fri, 22 Jan 2021 01:51:31 GMT", "version": "v1" }, { "created": "Fri, 29 Oct 2021 06:21:08 GMT", "version": "v2" } ]
2021-11-01
[ [ "Hu", "YaLu", "" ], [ "Sun", "ChuanLe", "" ], [ "Shen", "Xiao-Min", "" ], [ "Gao", "Jun", "" ] ]
We present predictions for hadronic decays of the Higgs boson at next-to-next-to-leading order (NNLO) in QCD matched with parton shower based on the POWHEG framework. Those include decays into bottom quarks with full bottom-quark mass dependence, light quarks, and gluons in the heavy top quark effective theory. Our calculations describe exclusive decays of the Higgs boson with leading logarithmic accuracy in the Sudakov region and next-to-leading order (NLO) accuracy matched with parton shower in the three-jet region, with normalizations fixed to the partial width at NNLO. We estimated remaining perturbative uncertainties taking typical event shape variables as an example and demonstrated the need of future improvements on both parton shower and matrix element calculations. The calculations can be used immediately in evaluations of the physics performances of detector designs for future Higgs factories.
hep-ph/9407275
Oleg Selyugin
S.V.Goloskokov, O.V.Selyugin
Spin Effects in pp-scattering at difraction range and RHIC energies
10 pages, LaTex, two Tables, 3 figs. {files .ps in the end this file} JINR preprint E2-94-262
Phys.Atom.Nucl. 58 (1995) 1791-1794; Yad.Fiz. 58 (1995) 1894-1897
null
null
hep-ph
null
The spin effects in nucleon-nucleon scattering are calculated in the framework of the dynamic model taking into account interactions at large distances and the strong form factors; the model factorization of the $NN$ amplitude into the spin-dependent hadron-pomeron vertex and high-energy spinless pomeron is obtained. Theoretical predictions for polarization and $A_{nn}$ are made for the diffraction range at the RHIC energies.
[ { "created": "Tue, 12 Jul 1994 11:00:18 GMT", "version": "v1" } ]
2009-09-25
[ [ "Goloskokov", "S. V.", "" ], [ "Selyugin", "O. V.", "" ] ]
The spin effects in nucleon-nucleon scattering are calculated in the framework of the dynamic model taking into account interactions at large distances and the strong form factors; the model factorization of the $NN$ amplitude into the spin-dependent hadron-pomeron vertex and high-energy spinless pomeron is obtained. Theoretical predictions for polarization and $A_{nn}$ are made for the diffraction range at the RHIC energies.
1905.02615
Christian Fischer
Paul C. Wallbott, Gernot Eichmann and Christian S. Fischer
$X(3872)$ as a four-quark state in a Dyson-Schwinger/Bethe-Salpeter approach
8 pages, 2 figures; v2: minor typos corrected
Phys. Rev. D 100, 014033 (2019)
10.1103/PhysRevD.100.014033
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We generalise the framework of Dyson-Schwinger and Bethe-Salpeter equations for four-quark states to accommodate the case of unequal quark masses. As a first application, we consider the quantum numbers $I(J^{PC})=0(1^{++})$ of the $X(3872)$ and study the four-quark states with quark contents $cq\bar{q}\bar{c}$ and $cs\bar{s}\bar{c}$. Their Bethe-Salpeter amplitudes are represented by a basis of heavy-light meson-meson, hadro-charmonium and diquark-antidiquark operators, which allows for a dynamical distinction between different internal configurations. In both cases we find the heavy-light meson-meson component to be dominant. For the putative $X(3872)$ we obtain a mass of $3916(74)$ MeV; the corresponding $cs\bar{s}\bar{c}$ state is predicted at $4068(61)$ MeV.
[ { "created": "Tue, 7 May 2019 14:38:38 GMT", "version": "v1" }, { "created": "Wed, 17 Jul 2019 13:12:33 GMT", "version": "v2" } ]
2019-08-07
[ [ "Wallbott", "Paul C.", "" ], [ "Eichmann", "Gernot", "" ], [ "Fischer", "Christian S.", "" ] ]
We generalise the framework of Dyson-Schwinger and Bethe-Salpeter equations for four-quark states to accommodate the case of unequal quark masses. As a first application, we consider the quantum numbers $I(J^{PC})=0(1^{++})$ of the $X(3872)$ and study the four-quark states with quark contents $cq\bar{q}\bar{c}$ and $cs\bar{s}\bar{c}$. Their Bethe-Salpeter amplitudes are represented by a basis of heavy-light meson-meson, hadro-charmonium and diquark-antidiquark operators, which allows for a dynamical distinction between different internal configurations. In both cases we find the heavy-light meson-meson component to be dominant. For the putative $X(3872)$ we obtain a mass of $3916(74)$ MeV; the corresponding $cs\bar{s}\bar{c}$ state is predicted at $4068(61)$ MeV.
2311.13941
Simone Rodini
Valerio Bertone, Rafael F. del Castillo, Miguel G. Echevarria, \'Oscar del R\'io, Simone Rodini
One-loop evolution of twist-2 generalized parton distributions
Updated list of references
null
null
DESY-23-188, IPARCOS-UCM-23-128
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the evolution of generalised parton distributions (GPDs) at the leading order in the strong coupling constant $\alpha_s$ for all of the twist-2 quark and gluon operators. We rederive the relevant one-loop evolution kernels, expressing them in a form suitable for implementation, and check analytically that some basic properties, such as DGLAP/ERBL limits and polynomiality conservation, are fulfilled. We also present a number of numerical results obtained with a public implementation of the evolution in the library {\tt APFEL++} and available within the {\tt PARTONS} framework.
[ { "created": "Thu, 23 Nov 2023 11:44:34 GMT", "version": "v1" }, { "created": "Tue, 13 Feb 2024 14:22:04 GMT", "version": "v2" }, { "created": "Thu, 15 Feb 2024 08:18:21 GMT", "version": "v3" } ]
2024-02-16
[ [ "Bertone", "Valerio", "" ], [ "del Castillo", "Rafael F.", "" ], [ "Echevarria", "Miguel G.", "" ], [ "del Río", "Óscar", "" ], [ "Rodini", "Simone", "" ] ]
We revisit the evolution of generalised parton distributions (GPDs) at the leading order in the strong coupling constant $\alpha_s$ for all of the twist-2 quark and gluon operators. We rederive the relevant one-loop evolution kernels, expressing them in a form suitable for implementation, and check analytically that some basic properties, such as DGLAP/ERBL limits and polynomiality conservation, are fulfilled. We also present a number of numerical results obtained with a public implementation of the evolution in the library {\tt APFEL++} and available within the {\tt PARTONS} framework.
2011.10434
Svetlana Belokurova
S.Belokurova
Study of strongly intense quantities and robust variances in multi-particle production at LHC energies
8 pages, 4 figures, reported at LXX International conference NUCLEUS - 2020. Nuclear physics and elementary particle physics. Nuclear physics technologies
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The strongly intense quantities and robust variances in processes of multi-particle production in pp and AA interactions at LHC energies was studied. The Monte Carlo and analytic modelling of these quantities in the framework of a quark-gluon string model were implies. The string fusion effects were also taken into account by implementing of a lattice (grid) in the impact parameter plane. Strongly intensive variable $\Sigma(n_F,\ n_B)$ was calculated for different energies for two values of the width of the observation rapidity windows as a function of the distance between the centres of this windows. Scaled variance $\omega_n$ and robust variance $R_n$ for different energies and for different width of the observation rapidity window was calculated by MC simulations.
[ { "created": "Fri, 20 Nov 2020 14:55:18 GMT", "version": "v1" } ]
2020-11-23
[ [ "Belokurova", "S.", "" ] ]
The strongly intense quantities and robust variances in processes of multi-particle production in pp and AA interactions at LHC energies was studied. The Monte Carlo and analytic modelling of these quantities in the framework of a quark-gluon string model were implies. The string fusion effects were also taken into account by implementing of a lattice (grid) in the impact parameter plane. Strongly intensive variable $\Sigma(n_F,\ n_B)$ was calculated for different energies for two values of the width of the observation rapidity windows as a function of the distance between the centres of this windows. Scaled variance $\omega_n$ and robust variance $R_n$ for different energies and for different width of the observation rapidity window was calculated by MC simulations.
1705.00001
Don Bunk
Don Bunk, Jay Hubisz, Bithika Jain
A Perturbative RS I Cosmological Phase Transition
34pp, 12 figures
null
10.1140/epjc/s10052-018-5529-2
null
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We identify a class of Randall-Sundrum type models with a successful first order cosmological phase transition during which a 5D dual of approximate conformal symmetry is spontaneously broken. Our focus is on soft-wall models that naturally realize a light radion/dilaton and suppressed dynamical contribution to the cosmological constant. We discuss phenomenology of the phase transition after developing a theoretical and numerical analysis of these models both at zero and finite temperature. We demonstrate a model with a TeV-Planck hierarchy and with a successful cosmological phase transition where the UV value of the curvature corresponds, via AdS/CFT, to an $N$ of $20$, where 5D gravity is expected to be firmly in the perturbative regime.
[ { "created": "Thu, 27 Apr 2017 18:00:13 GMT", "version": "v1" } ]
2018-03-14
[ [ "Bunk", "Don", "" ], [ "Hubisz", "Jay", "" ], [ "Jain", "Bithika", "" ] ]
We identify a class of Randall-Sundrum type models with a successful first order cosmological phase transition during which a 5D dual of approximate conformal symmetry is spontaneously broken. Our focus is on soft-wall models that naturally realize a light radion/dilaton and suppressed dynamical contribution to the cosmological constant. We discuss phenomenology of the phase transition after developing a theoretical and numerical analysis of these models both at zero and finite temperature. We demonstrate a model with a TeV-Planck hierarchy and with a successful cosmological phase transition where the UV value of the curvature corresponds, via AdS/CFT, to an $N$ of $20$, where 5D gravity is expected to be firmly in the perturbative regime.
1010.4185
Aleksandrs Aleksejevs
A. Aleksejevs, S. Barkanova, A. Ilyichev, Y. Kolomensky, V. Zykunov
One-loop electroweak corrections for polarized Moller scattering at different renormalization schemes and conditions
14 pages, 9 figures, extended analysis in CDR scheme
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using two different approaches, we perform updated and detailed calculations of the complete one-loop (Next-to-Leading Order (NLO)) set of electroweak radiative corrections to the parity violating e- e- -> e- e- (gamma) scattering asymmetry. Our first approach, more classical, relies on calculations "by hand" with reasonable approximations. Our second approach relies on program packages FeynArts, FormCalc, LoopTools, and FORM. The detailed numerical analysis of the various contributions is provided for a wide range of energies relevant for the ultra-precise 11 GeV MOLLER experiment planned at the Jefferson Laboratory, as well as future experiments at the International Linear Collider (ILC). The numerical results obtained within the on-shell renormalization scheme using two different sets of renormalization conditions are in excellent agreement. We also calculate the total NLO correction in the Constrained Differential Renormalization (CDR) scheme. Analysis of the results, along with the increasing experimental precision, shows that it is feasible that the corrections at the Next-to-Next-to-Leading Order (NNLO) level may be important for the next generation of high-precision experiments.
[ { "created": "Wed, 20 Oct 2010 12:50:16 GMT", "version": "v1" }, { "created": "Sat, 23 Oct 2010 23:06:17 GMT", "version": "v2" }, { "created": "Tue, 16 Aug 2011 20:42:25 GMT", "version": "v3" } ]
2011-08-18
[ [ "Aleksejevs", "A.", "" ], [ "Barkanova", "S.", "" ], [ "Ilyichev", "A.", "" ], [ "Kolomensky", "Y.", "" ], [ "Zykunov", "V.", "" ] ]
Using two different approaches, we perform updated and detailed calculations of the complete one-loop (Next-to-Leading Order (NLO)) set of electroweak radiative corrections to the parity violating e- e- -> e- e- (gamma) scattering asymmetry. Our first approach, more classical, relies on calculations "by hand" with reasonable approximations. Our second approach relies on program packages FeynArts, FormCalc, LoopTools, and FORM. The detailed numerical analysis of the various contributions is provided for a wide range of energies relevant for the ultra-precise 11 GeV MOLLER experiment planned at the Jefferson Laboratory, as well as future experiments at the International Linear Collider (ILC). The numerical results obtained within the on-shell renormalization scheme using two different sets of renormalization conditions are in excellent agreement. We also calculate the total NLO correction in the Constrained Differential Renormalization (CDR) scheme. Analysis of the results, along with the increasing experimental precision, shows that it is feasible that the corrections at the Next-to-Next-to-Leading Order (NNLO) level may be important for the next generation of high-precision experiments.
1412.1744
Sushant Raut
Monojit Ghosh, Srubabati Goswami, Sushant K. Raut
Maximising the DUNE early physics output with current experiments
Version accepted for publication in Eur. Phys. J. C
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Deep Underground Neutrino Experiment (DUNE) is a proposed next generation superbeam experiment at Fermilab. Its aims include measuring the unknown neutrino oscillation parameters -- the neutrino mass hierarchy, the octant of the mixing angle $\theta_{23}$ and the CP violating phase $\delta_{CP}$. The current and upcoming experiments T2K, NOvA and ICAL@INO will also be collecting data for the same measurements. In this paper, we explore the sensitivity reach of DUNE in combination with these other experiments. We evaluate the least exposure required by DUNE to determine the above three unknown parameters with reasonable confidence. We find that for each case, the inclusion of data from T2K, NOvA and ICAL@INO help to achieve the same sensitivity with a reduced exposure from DUNE thereby helping to economize the configuration. Further, we quantify the effect of the proposed near detector on systematic errors and study the consequent improvement in sensitivity. We also examine the role played by the second oscillation cycle in furthering the physics reach of DUNE. Finally, we present an optimization study of the neutrino-antineutrino running of DUNE.
[ { "created": "Thu, 4 Dec 2014 17:55:58 GMT", "version": "v1" }, { "created": "Tue, 1 Mar 2016 14:25:18 GMT", "version": "v2" }, { "created": "Thu, 3 Mar 2016 09:18:15 GMT", "version": "v3" } ]
2016-03-04
[ [ "Ghosh", "Monojit", "" ], [ "Goswami", "Srubabati", "" ], [ "Raut", "Sushant K.", "" ] ]
The Deep Underground Neutrino Experiment (DUNE) is a proposed next generation superbeam experiment at Fermilab. Its aims include measuring the unknown neutrino oscillation parameters -- the neutrino mass hierarchy, the octant of the mixing angle $\theta_{23}$ and the CP violating phase $\delta_{CP}$. The current and upcoming experiments T2K, NOvA and ICAL@INO will also be collecting data for the same measurements. In this paper, we explore the sensitivity reach of DUNE in combination with these other experiments. We evaluate the least exposure required by DUNE to determine the above three unknown parameters with reasonable confidence. We find that for each case, the inclusion of data from T2K, NOvA and ICAL@INO help to achieve the same sensitivity with a reduced exposure from DUNE thereby helping to economize the configuration. Further, we quantify the effect of the proposed near detector on systematic errors and study the consequent improvement in sensitivity. We also examine the role played by the second oscillation cycle in furthering the physics reach of DUNE. Finally, we present an optimization study of the neutrino-antineutrino running of DUNE.
hep-ph/0606148
Jens Erler
Jens Erler
Fit to Electroweak Precision Data
4 pages, presented at the 2006 Conference on the Intersections of Particle and Nuclear Physics (CIPANP 2006), Rio Grande, Puerto Rico, May 30 -- June 3, 2006
null
10.1063/1.2402624
null
hep-ph hep-ex
null
A brief review of electroweak precision data from LEP, SLC, the Tevatron, and low energies is presented. The global fit to all data including the most recent results on the masses of the top quark and the W boson reinforces the preference for a relatively light Higgs boson. I will also give an outlook on future developments at the Tevatron Run II, CEBAF, the LHC, and the ILC.
[ { "created": "Mon, 12 Jun 2006 22:01:59 GMT", "version": "v1" } ]
2009-11-11
[ [ "Erler", "Jens", "" ] ]
A brief review of electroweak precision data from LEP, SLC, the Tevatron, and low energies is presented. The global fit to all data including the most recent results on the masses of the top quark and the W boson reinforces the preference for a relatively light Higgs boson. I will also give an outlook on future developments at the Tevatron Run II, CEBAF, the LHC, and the ILC.
1311.7392
Krzysztof Golec-Biernat
Krzysztof Golec-Biernat and Emilia Lewandowska
Initial conditions for evolution of double parton distributions
presented at DIS2013 at Marseilles, France, 22-26 April, 2013, one reference added
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Double parton distribution functions (DPDFs) are used in the QCD description of double parton scattering. The DPDFs evolve with hard scales through relatively new QCD evolution equations which obey nontrivial momentum and valence quark number sum rules. Based on the constructed numerical program, we present results on the QCD evolution of the DPDFs. In particular, we discuss the problem how to specify initial conditions for the evolution equations which exactly fulfill the sum rules.
[ { "created": "Thu, 28 Nov 2013 18:13:48 GMT", "version": "v1" }, { "created": "Thu, 19 Dec 2013 15:28:35 GMT", "version": "v2" } ]
2013-12-20
[ [ "Golec-Biernat", "Krzysztof", "" ], [ "Lewandowska", "Emilia", "" ] ]
Double parton distribution functions (DPDFs) are used in the QCD description of double parton scattering. The DPDFs evolve with hard scales through relatively new QCD evolution equations which obey nontrivial momentum and valence quark number sum rules. Based on the constructed numerical program, we present results on the QCD evolution of the DPDFs. In particular, we discuss the problem how to specify initial conditions for the evolution equations which exactly fulfill the sum rules.
hep-ph/0512187
Frank Wilczek
Frank Wilczek
Enlightenment, Knowledge, Ignorance, Temptation
10 pages, 5 figures. Summary talk at ``Expectations of a Final Theory'', Trinity College, Cambridge, September 2005. v2: date of earlier conference corrected (2003->2001)
null
null
null
hep-ph astro-ph hep-th
null
I discuss the historical and conceptual roots of reasoning about the parameters of fundamental physics and cosmology based on selection effects. I argue concretely that such reasoning can and should be combined with arguments based on symmetry and dynamics; it supplements them, but does not replace them.
[ { "created": "Wed, 14 Dec 2005 20:46:29 GMT", "version": "v1" }, { "created": "Sat, 17 Dec 2005 23:05:34 GMT", "version": "v2" } ]
2007-05-23
[ [ "Wilczek", "Frank", "" ] ]
I discuss the historical and conceptual roots of reasoning about the parameters of fundamental physics and cosmology based on selection effects. I argue concretely that such reasoning can and should be combined with arguments based on symmetry and dynamics; it supplements them, but does not replace them.
hep-ph/9909561
David London
B. Kayser and D. London
Exploring CP Violation with B_d -> D K_s Decays
15 pages, LaTeX, no figures
Phys.Rev.D61:116013,2000
10.1103/PhysRevD.61.116013
NSF-PT-99-5, UdeM-GPP-TH-98-47
hep-ph
null
We (re)examine CP violation in the decays B_d -> D K_s, where D represents D^0, D(bar), or one of their excited states. The quantity $\sin^2(2\beta + \gamma)$ can be extracted from the time-dependent rates for $B_d(t) -> {\bar D}^{**0} K_s$ and $B_d(t) -> D^{**0} K_s$, where the $D^{**0}$ decays to $D^{(*)+}\pi^-$. If one considers a non-CP-eigenstate hadronic final state to which both D(bar) and D^0 can decay (e.g. $K^+\pi^-$), then one can obtain two of the angles of the unitarity triangle from measurements of the time-dependent rates for $B_d(t) -> (K^+\pi^-)_{D K_s}$ and $B_d(t) -> (K^-\pi^+)_{D K_s}$. There are no penguin contributions to these decays, so all measurements are theoretically clean.
[ { "created": "Wed, 29 Sep 1999 20:09:13 GMT", "version": "v1" } ]
2014-11-17
[ [ "Kayser", "B.", "" ], [ "London", "D.", "" ] ]
We (re)examine CP violation in the decays B_d -> D K_s, where D represents D^0, D(bar), or one of their excited states. The quantity $\sin^2(2\beta + \gamma)$ can be extracted from the time-dependent rates for $B_d(t) -> {\bar D}^{**0} K_s$ and $B_d(t) -> D^{**0} K_s$, where the $D^{**0}$ decays to $D^{(*)+}\pi^-$. If one considers a non-CP-eigenstate hadronic final state to which both D(bar) and D^0 can decay (e.g. $K^+\pi^-$), then one can obtain two of the angles of the unitarity triangle from measurements of the time-dependent rates for $B_d(t) -> (K^+\pi^-)_{D K_s}$ and $B_d(t) -> (K^-\pi^+)_{D K_s}$. There are no penguin contributions to these decays, so all measurements are theoretically clean.
0712.2176
Georg Raffelt
Andreu Esteban-Pretel, Sergio Pastor, Ricard Tomas, Georg Raffelt, Gunter Sigl
Multi-angle effects in collective supernova neutrino oscillations
Contribution to TAUP 07, Sendai, Japan
J.Phys.Conf.Ser.120:052021,2008
10.1088/1742-6596/120/5/052021
MPP-2007-188
hep-ph
null
We study two-flavor collective neutrino oscillations in the dense-neutrino region above the neutrino sphere in a supernova (SN). The angular dependence of the neutrino-neutrino interaction potential causes "multi-angle" effects that can lead either to complete kinematical decoherence in flavor space or only to small differences between different trajectories. This nonlinear system switches abruptly between "self-maintained coherence" and "self-induced decoherence" among the angular modes, depending on the strength of the deleptonization flux. For a realistic SN the quasi single-angle behavior is probably typical, simplifying the numerical treatment and probably allowing for the survival of observational features of flavor oscillations.
[ { "created": "Thu, 13 Dec 2007 15:48:08 GMT", "version": "v1" } ]
2008-11-26
[ [ "Esteban-Pretel", "Andreu", "" ], [ "Pastor", "Sergio", "" ], [ "Tomas", "Ricard", "" ], [ "Raffelt", "Georg", "" ], [ "Sigl", "Gunter", "" ] ]
We study two-flavor collective neutrino oscillations in the dense-neutrino region above the neutrino sphere in a supernova (SN). The angular dependence of the neutrino-neutrino interaction potential causes "multi-angle" effects that can lead either to complete kinematical decoherence in flavor space or only to small differences between different trajectories. This nonlinear system switches abruptly between "self-maintained coherence" and "self-induced decoherence" among the angular modes, depending on the strength of the deleptonization flux. For a realistic SN the quasi single-angle behavior is probably typical, simplifying the numerical treatment and probably allowing for the survival of observational features of flavor oscillations.
hep-ph/0309202
Massimo Blasone Dr
Massimo Blasone, Giuseppe Vitiello
Quantum Field Theory of particle mixing and oscillations
24 pages, 3 figures. Presented at "Symmetries in Science XIII", Kloster Mehrerau, Bregenz, Austria - July 20-24, 2003
null
null
null
hep-ph
null
We report on recent results on the Quantum Field Theory of mixed particles. The quantization procedure is discussed in detail, both for fermions and for bosons and the unitary inequivalence of the flavor and mass representations is proved. Oscillation formulas exhibiting corrections with respect to the usual quantum mechanical ones are then derived.
[ { "created": "Wed, 17 Sep 2003 16:39:30 GMT", "version": "v1" } ]
2007-05-23
[ [ "Blasone", "Massimo", "" ], [ "Vitiello", "Giuseppe", "" ] ]
We report on recent results on the Quantum Field Theory of mixed particles. The quantization procedure is discussed in detail, both for fermions and for bosons and the unitary inequivalence of the flavor and mass representations is proved. Oscillation formulas exhibiting corrections with respect to the usual quantum mechanical ones are then derived.
0706.4443
Hendrik van Hees
H. van Hees and R. Rapp
Thermal Dileptons at LHC
2 pages, 2 figures, contributed to Workshop on Heavy Ion Collisions at the LHC: Last Call for Predictions, Geneva, Switzerland, 14 May - 8 Jun 2007 v2: acknowledgment included
Journal of Physics G 35, 1 (2008), p 153
10.1088/0954-3899/35/5/054001
null
hep-ph nucl-ex nucl-th
null
We predict dilepton invariant-mass spectra for central 5.5 ATeV Pb-Pb collisions at LHC. Hadronic emission in the low-mass region is calculated using in-medium spectral functions of light vector mesons within hadronic many-body theory. In the intermediate-mass region thermal radiation from the Quark-Gluon Plasma, evaluated perturbatively with hard-thermal loop corrections, takes over. An important source over the entire mass range are decays of correlated open-charm hadrons, rendering the nuclear modification of charm and bottom spectra a critical ingredient.
[ { "created": "Fri, 29 Jun 2007 15:35:36 GMT", "version": "v1" }, { "created": "Sat, 30 Jun 2007 22:23:44 GMT", "version": "v2" } ]
2008-04-22
[ [ "van Hees", "H.", "" ], [ "Rapp", "R.", "" ] ]
We predict dilepton invariant-mass spectra for central 5.5 ATeV Pb-Pb collisions at LHC. Hadronic emission in the low-mass region is calculated using in-medium spectral functions of light vector mesons within hadronic many-body theory. In the intermediate-mass region thermal radiation from the Quark-Gluon Plasma, evaluated perturbatively with hard-thermal loop corrections, takes over. An important source over the entire mass range are decays of correlated open-charm hadrons, rendering the nuclear modification of charm and bottom spectra a critical ingredient.
1605.09359
Hua-Sheng Shao
Goutam Das, Celine Degrande, Valentin Hirschi, Fabio Maltoni, Hua-Sheng Shao
NLO predictions for the production of a spin-two particle at the LHC
10 pages, 5 figures, 1 table; v2: update references, rewrite the introduction, add mass scanning, remove all 750 GeV references, the model file can be found http://feynrules.irmp.ucl.ac.be/wiki/NLOModels
null
10.1016/j.physletb.2017.05.007
CERN-TH-2016-122, CP3-16-25, IPPP/16/42, MCnet-16-17, SLAC-PUB-16528
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We obtain predictions accurate at the next-to-leading order in QCD for the production of a generic spin-two particle in the most relevant channels at the LHC: production in association with coloured particles (inclusive, one jet, two jets and $t\bar t$), with vector bosons ($Z,W^\pm,\gamma$) and with the Higgs boson. We present total and differential cross sections as well as branching ratios as a function of the mass and the collision energy also considering the case of non-universal couplings to standard model particles. We find that the next-to-leading order corrections give rise to sizeable $K$ factors for many channels, in some cases exposing the unitarity-violating behaviour of non-universal couplings scenarios, and in general greatly reduce the theoretical uncertainties. Our predictions are publicly available in the MadGraph5\_aMC@NLO framework and can, therefore, be directly used in experimental simulations of spin-two particle production for arbitrary values of the mass and couplings.
[ { "created": "Mon, 30 May 2016 19:23:02 GMT", "version": "v1" }, { "created": "Mon, 10 Apr 2017 19:18:48 GMT", "version": "v2" } ]
2017-05-10
[ [ "Das", "Goutam", "" ], [ "Degrande", "Celine", "" ], [ "Hirschi", "Valentin", "" ], [ "Maltoni", "Fabio", "" ], [ "Shao", "Hua-Sheng", "" ] ]
We obtain predictions accurate at the next-to-leading order in QCD for the production of a generic spin-two particle in the most relevant channels at the LHC: production in association with coloured particles (inclusive, one jet, two jets and $t\bar t$), with vector bosons ($Z,W^\pm,\gamma$) and with the Higgs boson. We present total and differential cross sections as well as branching ratios as a function of the mass and the collision energy also considering the case of non-universal couplings to standard model particles. We find that the next-to-leading order corrections give rise to sizeable $K$ factors for many channels, in some cases exposing the unitarity-violating behaviour of non-universal couplings scenarios, and in general greatly reduce the theoretical uncertainties. Our predictions are publicly available in the MadGraph5\_aMC@NLO framework and can, therefore, be directly used in experimental simulations of spin-two particle production for arbitrary values of the mass and couplings.
2004.13762
Pritam Das
Lavina Sarma, Pritam Das, Mrinal Kumar Das
Scalar dark matter and leptogenesis in the minimal scotogenic model
Newly added analysis and references. Version accepted for publication in NPB
null
10.1016/j.nuclphysb.2020.115300
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the minimal scotogenic model constituting an additional inert Higgs doublet and three sets of right-handed neutrinos. The scotogenic model connects dark matter, baryon asymmetry of the Universe and neutrino oscillation data. In our work, we obtain baryogenesis by the decay of TeV scale heavy neutral singlet fermion ($N_{2}$). We primarily focus on the intermediate-mass region of dark matter within $M_W<M_{DM}\le550$ GeV, where observed relic density is suppressed due to co-annihilation processes. We consider thermal as well as the non-thermal approach of dark matter production and explore the possibility of the lightest stable candidate being a dark matter candidate. Within the inert Higgs doublet (IHD) desert, we explore a new allowed region of dark matter masses for the non-thermal generation of dark matter with a mass splitting of 10 GeV among the inert scalars. We also see the variation of relic abundance for unequal mass splitting among the scalars. The KamLand-Zen bound on the effective mass of the active neutrinos is also verified in this study.
[ { "created": "Tue, 28 Apr 2020 18:21:48 GMT", "version": "v1" }, { "created": "Sun, 12 Jul 2020 15:22:06 GMT", "version": "v2" }, { "created": "Sun, 27 Dec 2020 07:04:24 GMT", "version": "v3" } ]
2021-02-24
[ [ "Sarma", "Lavina", "" ], [ "Das", "Pritam", "" ], [ "Das", "Mrinal Kumar", "" ] ]
We study the minimal scotogenic model constituting an additional inert Higgs doublet and three sets of right-handed neutrinos. The scotogenic model connects dark matter, baryon asymmetry of the Universe and neutrino oscillation data. In our work, we obtain baryogenesis by the decay of TeV scale heavy neutral singlet fermion ($N_{2}$). We primarily focus on the intermediate-mass region of dark matter within $M_W<M_{DM}\le550$ GeV, where observed relic density is suppressed due to co-annihilation processes. We consider thermal as well as the non-thermal approach of dark matter production and explore the possibility of the lightest stable candidate being a dark matter candidate. Within the inert Higgs doublet (IHD) desert, we explore a new allowed region of dark matter masses for the non-thermal generation of dark matter with a mass splitting of 10 GeV among the inert scalars. We also see the variation of relic abundance for unequal mass splitting among the scalars. The KamLand-Zen bound on the effective mass of the active neutrinos is also verified in this study.
2111.02536
Alfredo Walter Mario Guerrera
Jorge Alda Gallo, Alfredo Walter Mario Guerrera, Siannah Pe\~naranda, Stefano Rigolin
Leptonic Meson Decays into Invisible ALP
15 pages, 5 figures, 2 tables
null
10.1016/j.nuclphysb.2022.115791
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The theoretical calculation of pseudo-scalar leptonic decay widths into an invisible ALP, $M \to \ell\, \nu_\ell\, a$, is reviewed. Assuming generic flavour-conserving ALP couplings to SM fermions and a generic ALP mass, $m_a$, the latest experimental results for pseudo-scalar leptonic decays are used to provide updated bounds on the ALP-fermion Lagrangian sector. Constrains on the ALP-quark couplings obtained from these channels are not yet competitive with the ones derived from FCNC processes, like $M\to P\,a$ decays. These leptonic decays can, however, provide the most stringent model-independent upper bounds on ALP-leptons couplings for $m_a$ in the (sub)-GeV range.
[ { "created": "Wed, 3 Nov 2021 21:43:13 GMT", "version": "v1" } ]
2022-05-11
[ [ "Gallo", "Jorge Alda", "" ], [ "Guerrera", "Alfredo Walter Mario", "" ], [ "Peñaranda", "Siannah", "" ], [ "Rigolin", "Stefano", "" ] ]
The theoretical calculation of pseudo-scalar leptonic decay widths into an invisible ALP, $M \to \ell\, \nu_\ell\, a$, is reviewed. Assuming generic flavour-conserving ALP couplings to SM fermions and a generic ALP mass, $m_a$, the latest experimental results for pseudo-scalar leptonic decays are used to provide updated bounds on the ALP-fermion Lagrangian sector. Constrains on the ALP-quark couplings obtained from these channels are not yet competitive with the ones derived from FCNC processes, like $M\to P\,a$ decays. These leptonic decays can, however, provide the most stringent model-independent upper bounds on ALP-leptons couplings for $m_a$ in the (sub)-GeV range.
2106.11320
Konstantin Springmann
Reuven Balkin, Javi Serra, Konstantin Springmann, Stefan Stelzl and Andreas Weiler
Runaway Relaxion from Finite Density
30 pages, 5 figures and several appendices
null
10.1007/JHEP06(2022)023
TUM-HEP-1348/21
hep-ph astro-ph.CO astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Finite density effects can destabilize the metastable vacua in relaxion models. Focusing on stars as nucleation seeds, we derive the conditions that lead to the formation and runaway of a relaxion bubble of a lower energy minimum than in vacuum. The resulting late-time phase transition in the universe allows us to set new constraints on the parameter space of relaxion models. We also find that similar instabilities can be triggered by the large electromagnetic fields around rotating neutron stars.
[ { "created": "Mon, 21 Jun 2021 18:00:01 GMT", "version": "v1" } ]
2022-06-22
[ [ "Balkin", "Reuven", "" ], [ "Serra", "Javi", "" ], [ "Springmann", "Konstantin", "" ], [ "Stelzl", "Stefan", "" ], [ "Weiler", "Andreas", "" ] ]
Finite density effects can destabilize the metastable vacua in relaxion models. Focusing on stars as nucleation seeds, we derive the conditions that lead to the formation and runaway of a relaxion bubble of a lower energy minimum than in vacuum. The resulting late-time phase transition in the universe allows us to set new constraints on the parameter space of relaxion models. We also find that similar instabilities can be triggered by the large electromagnetic fields around rotating neutron stars.
1210.5415
York Schroder
Ioan Ghisoiu, York Schroder
Automated computation meets hot QCD
8 pages, to appear in the Proceedings of the 11th Workshop 'Loops and Legs in Quantum Field Theory', Wernigerode, Germany, 2012
null
null
BI-TP 2012/45
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We give a short review on recent progress in the field of automated calculations in finite-temperature field theory, where integration-by-parts techniques have proven (almost) as useful as in the zero-temperature case. Furthermore, we provide one concrete example of an evaluation of a new three-loop master sum-integral that exhibits maximal divergence.
[ { "created": "Fri, 19 Oct 2012 13:29:17 GMT", "version": "v1" } ]
2012-10-22
[ [ "Ghisoiu", "Ioan", "" ], [ "Schroder", "York", "" ] ]
We give a short review on recent progress in the field of automated calculations in finite-temperature field theory, where integration-by-parts techniques have proven (almost) as useful as in the zero-temperature case. Furthermore, we provide one concrete example of an evaluation of a new three-loop master sum-integral that exhibits maximal divergence.
1004.3449
Vladimir Pascalutsa
Tim Ledwig, Vladimir Pascalutsa, Marc Vanderhaeghen (Kernphysik, Mainz U.)
A dispersion relation for the pion-mass dependence of hadron properties
8 pages, 4 figs
Phys.Lett.B690:129-134,2010
10.1016/j.physletb.2010.05.023
MKPH-T-10-02
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a dispersion relation in the pion-mass squared, which static quantities (nucleon mass, magnetic moment, etc.) obey under the assumption of analyticity in the entire complex $m_\pi^2$ plane modulo a cut at negative $m_\pi^2$ associated with pion production. The relation is verified here in a number of examples of nucleon and $\Delta$-isobar properties computed in chiral perturbation theory up to order $p^3$. We outline a method to obtain relations for other mass-dependencies, and illustrate it on a two-loop example.
[ { "created": "Tue, 20 Apr 2010 13:47:58 GMT", "version": "v1" } ]
2014-11-20
[ [ "Ledwig", "Tim", "", "Kernphysik, Mainz\n U." ], [ "Pascalutsa", "Vladimir", "", "Kernphysik, Mainz\n U." ], [ "Vanderhaeghen", "Marc", "", "Kernphysik, Mainz\n U." ] ]
We present a dispersion relation in the pion-mass squared, which static quantities (nucleon mass, magnetic moment, etc.) obey under the assumption of analyticity in the entire complex $m_\pi^2$ plane modulo a cut at negative $m_\pi^2$ associated with pion production. The relation is verified here in a number of examples of nucleon and $\Delta$-isobar properties computed in chiral perturbation theory up to order $p^3$. We outline a method to obtain relations for other mass-dependencies, and illustrate it on a two-loop example.
hep-ph/0508115
Mohamad Ali Gomshi Nobary
M.A. Gomshi Nobary and R. Sepahvand
An ivestigation of triply heavy baryon production at hadron colliders
9 pages, 5 figures, To appear in Nuclear Physics B
Nucl.Phys.B741:34-41,2006
10.1016/j.nuclphysb.2006.01.043
Razi-hep-124
hep-ph
null
The triply heavy baryons have a rather diverse mass range. While some of them possess considerable production rates at existing facilities, others need to be produced at future high energy colliders. Here we study the direct fragmentation production of the$\Omega_{ccc}$ and $\Omega_{bbb}$ baryons as the prototypes of triply heavy baryons at the hadron colliders with different $\sqrt{s}$. We present and compare the transverse momentum distributions of the differential cross sections, $p_T^{\rm min}$ distributions of total cross sections and the integrated total cross sections of these states at the RHIC, the Tevatron Run II and the CERN LHC.
[ { "created": "Wed, 10 Aug 2005 09:36:09 GMT", "version": "v1" }, { "created": "Wed, 1 Feb 2006 05:48:53 GMT", "version": "v2" }, { "created": "Mon, 6 Feb 2006 18:42:45 GMT", "version": "v3" } ]
2008-11-26
[ [ "Nobary", "M. A. Gomshi", "" ], [ "Sepahvand", "R.", "" ] ]
The triply heavy baryons have a rather diverse mass range. While some of them possess considerable production rates at existing facilities, others need to be produced at future high energy colliders. Here we study the direct fragmentation production of the$\Omega_{ccc}$ and $\Omega_{bbb}$ baryons as the prototypes of triply heavy baryons at the hadron colliders with different $\sqrt{s}$. We present and compare the transverse momentum distributions of the differential cross sections, $p_T^{\rm min}$ distributions of total cross sections and the integrated total cross sections of these states at the RHIC, the Tevatron Run II and the CERN LHC.
hep-ph/9907335
Alexander lanyov
A.A.Bel'kov, G.Bohm, A.V.Lanyov, A.A.Moshkin
Phenomenological analysis of epsilon'/epsilon within an effective chiral lagrangian approach at O(p^6)
35 pages, 17 Postscript figures, uses epsf.sty; Discussion of paper by S.Bertolini and M.Fabbrichesi was added into conclusion, no other changes
null
null
JINR E2-99-236
hep-ph
null
We have combined a new systematic calculation of mesonic matrix elements at O(p^6) from an effective chiral lagrangian approach with Wilson coefficients taken from paper by G.Buchalla et al. Rev.Mod.Phys. 68 (1996) 1125, derived in the framework of perturbative QCD, and restricted partly by experimental data. We derive complete expressions for K-->2pi amplitudes and compare the results for epsilon'/epsilon with experiment.
[ { "created": "Tue, 13 Jul 1999 13:35:09 GMT", "version": "v1" }, { "created": "Wed, 8 Sep 1999 12:09:51 GMT", "version": "v2" }, { "created": "Tue, 28 Sep 1999 15:40:19 GMT", "version": "v3" } ]
2007-05-23
[ [ "Bel'kov", "A. A.", "" ], [ "Bohm", "G.", "" ], [ "Lanyov", "A. V.", "" ], [ "Moshkin", "A. A.", "" ] ]
We have combined a new systematic calculation of mesonic matrix elements at O(p^6) from an effective chiral lagrangian approach with Wilson coefficients taken from paper by G.Buchalla et al. Rev.Mod.Phys. 68 (1996) 1125, derived in the framework of perturbative QCD, and restricted partly by experimental data. We derive complete expressions for K-->2pi amplitudes and compare the results for epsilon'/epsilon with experiment.
hep-ph/0212151
John F. Gunion
J. Gunion (UCD), T. Han (Wisconsin), J. Jiang (ANL), A. Sopczak (Lancaster)
Determining $\tan\beta$ with Neutral and Charged Higgs Bosons at a Future $e^+e^-$ Linear Collider
25 pages, 8 figures, revtex4
Phys.Lett. B565 (2003) 42-60
10.1016/S0370-2693(03)00763-9
UCD-02-16
hep-ph
null
The ratio of neutral Higgs field vacuum expectation values, tan(beta), is one of the most important parameters to determine in either the Minimal Supersymmetric Standard Model (MSSM) or a general type-II Two-Higgs Doublet Model (2HDM). Assuming an energy and integrated luminosity of sqrts=500 GeV and L=2000 fb-1 at a future linear collider (LC), we show that a very accurate determination of tan(beta) will be possible for low and high tan(beta) values by measuring the production rates of Higgs bosons and reconstructing Higgs boson decays. In particular, based on a TESLA simulation, and assuming no other light Higgs bosons and 100<=mA<=200 GeV, we find that the rate for the process e+e- --> bbA --> bbbb provides a good determination of tan(beta) at high tan(beta). In the MSSM Higgs sector, in the sample case of mA = 200 GeV, we find that the rates for e+e- --> bbA+bbH --> bbbb and for e+e- --> HA --> bbbb provide a good determination of tan(beta) at high and low tan(beta), respectively. We also show that the direct measurement of the average total widths of the H and A in e+e- --> HA --> bbbb events provides an excellent determination of tan(beta) at large values. In addition, the charged Higgs boson process e+e- --> H+H- --> tbtb has been studied. The sensitivity to tan(beta) at the LHC obtained directly from heavy Higgs boson production is briefly compared to the LC results.
[ { "created": "Wed, 11 Dec 2002 18:30:26 GMT", "version": "v1" } ]
2009-11-07
[ [ "Gunion", "J.", "", "UCD" ], [ "Han", "T.", "", "Wisconsin" ], [ "Jiang", "J.", "", "ANL" ], [ "Sopczak", "A.", "", "Lancaster" ] ]
The ratio of neutral Higgs field vacuum expectation values, tan(beta), is one of the most important parameters to determine in either the Minimal Supersymmetric Standard Model (MSSM) or a general type-II Two-Higgs Doublet Model (2HDM). Assuming an energy and integrated luminosity of sqrts=500 GeV and L=2000 fb-1 at a future linear collider (LC), we show that a very accurate determination of tan(beta) will be possible for low and high tan(beta) values by measuring the production rates of Higgs bosons and reconstructing Higgs boson decays. In particular, based on a TESLA simulation, and assuming no other light Higgs bosons and 100<=mA<=200 GeV, we find that the rate for the process e+e- --> bbA --> bbbb provides a good determination of tan(beta) at high tan(beta). In the MSSM Higgs sector, in the sample case of mA = 200 GeV, we find that the rates for e+e- --> bbA+bbH --> bbbb and for e+e- --> HA --> bbbb provide a good determination of tan(beta) at high and low tan(beta), respectively. We also show that the direct measurement of the average total widths of the H and A in e+e- --> HA --> bbbb events provides an excellent determination of tan(beta) at large values. In addition, the charged Higgs boson process e+e- --> H+H- --> tbtb has been studied. The sensitivity to tan(beta) at the LHC obtained directly from heavy Higgs boson production is briefly compared to the LC results.
1204.0451
Marko Djuri\'c
Richard Brower, Marko Djuri\'c, Chung-I Tan
Holographic Double Diffractive Production of Higgs and the AdS Graviton/Pomeron
Talk at the Eleventh Workshop on Non-Perturbative Quantum Chromodynamics at l'Institut d'Astrophysique de Paris, June 6-10, 2011
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The holographic approach to double diffractive Higgs production is presented for the AdS graviton/Pomeron. The goal is to provide a predictive phenomenology for the strong coupling expansion of QCD. This is the first step to set up the framework for the double diffractive Higgs production in anticipation of experimental observations at the LHC. Comparisons are made with the weak coupling approach based on the BFKL Pomeron models and soft Regge parameterizations.
[ { "created": "Mon, 2 Apr 2012 16:18:43 GMT", "version": "v1" } ]
2012-04-03
[ [ "Brower", "Richard", "" ], [ "Djurić", "Marko", "" ], [ "Tan", "Chung-I", "" ] ]
The holographic approach to double diffractive Higgs production is presented for the AdS graviton/Pomeron. The goal is to provide a predictive phenomenology for the strong coupling expansion of QCD. This is the first step to set up the framework for the double diffractive Higgs production in anticipation of experimental observations at the LHC. Comparisons are made with the weak coupling approach based on the BFKL Pomeron models and soft Regge parameterizations.
1007.3454
Steffen Schumann
Steffen Schumann
W+jets as a background to top physics: the quest for many jets
Talk given at Top 2010, Bruges, Belgium, May 31 - June 4, 2010
null
10.1393/ncc/i2010-10660-7
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The latest progress in calculating electroweak gauge boson production in association with QCD jets at hadron colliders is summarized. Particular emphasis is given to the recently completed QCD one-loop calculations of W+3jets and Wb final states. Furthermore recent developments in improving Monte Carlo event generators by means of combining tree-level matrix elements with parton showers is reviewed.
[ { "created": "Tue, 20 Jul 2010 15:47:55 GMT", "version": "v1" } ]
2022-03-02
[ [ "Schumann", "Steffen", "" ] ]
The latest progress in calculating electroweak gauge boson production in association with QCD jets at hadron colliders is summarized. Particular emphasis is given to the recently completed QCD one-loop calculations of W+3jets and Wb final states. Furthermore recent developments in improving Monte Carlo event generators by means of combining tree-level matrix elements with parton showers is reviewed.
0902.3615
Joerg Jaeckel
Felix Bruemmer and Joerg Jaeckel
Minicharges and Magnetic Monopoles
9 pages, 1 figure
Phys.Lett.B675:360-364,2009
10.1016/j.physletb.2009.04.041
DCPT/09/20; IPPP/09/10
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Minicharged particles arise naturally in extensions of the Standard Model with a kinetic mixing term between the ordinary electromagnetic U(1) and an extra "hidden sector" U(1). In this note we study the compatibility of these particles with the existence of magnetic monopoles. We find that angular momentum quantization allows only certain combinations of ordinary and hidden monopole charge. Using the example where one of the U(1)s originates from a spontaneously broken SU(2), we demonstrate that exactly the allowed types of monopoles arise as 't Hooft-Polyakov monopoles.
[ { "created": "Fri, 20 Feb 2009 16:55:58 GMT", "version": "v1" } ]
2014-11-18
[ [ "Bruemmer", "Felix", "" ], [ "Jaeckel", "Joerg", "" ] ]
Minicharged particles arise naturally in extensions of the Standard Model with a kinetic mixing term between the ordinary electromagnetic U(1) and an extra "hidden sector" U(1). In this note we study the compatibility of these particles with the existence of magnetic monopoles. We find that angular momentum quantization allows only certain combinations of ordinary and hidden monopole charge. Using the example where one of the U(1)s originates from a spontaneously broken SU(2), we demonstrate that exactly the allowed types of monopoles arise as 't Hooft-Polyakov monopoles.
1511.03548
Grigorios Chachamis
G. Chachamis, A. Sabio Vera
A Monte Carlo study of double logarithms in the small x region
12 pages, 5 figures
Phys. Rev. D 93, 074004 (2016)
10.1103/PhysRevD.93.074004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the effect of the resummation of collinear double logarithms in the BFKL gluon Green function using the Monte Carlo event generator BFKLex. The resummed collinear terms in transverse momentum space were calculated in Ref. [1] and correspond to the addition to the NLO BFKL kernel of a Bessel function of the first kind whose argument contains the strong coupling and a double logarithm of the ratio of the squared transverse momenta of the reggeized gluons. We discuss how these additional terms improve the collinear convergence of the whole approach and reduce the asymptotic growth with energy of cross sections. Taking advantage of the Monte Carlo implementation, we show how the new results reduce the diffusion of the gluon ladder into infrared and ultraviolet transverse momentum scales, while strongly affecting final state configurations by reducing the mini-jet multiplicity.
[ { "created": "Wed, 11 Nov 2015 16:01:51 GMT", "version": "v1" } ]
2016-04-13
[ [ "Chachamis", "G.", "" ], [ "Vera", "A. Sabio", "" ] ]
We investigate the effect of the resummation of collinear double logarithms in the BFKL gluon Green function using the Monte Carlo event generator BFKLex. The resummed collinear terms in transverse momentum space were calculated in Ref. [1] and correspond to the addition to the NLO BFKL kernel of a Bessel function of the first kind whose argument contains the strong coupling and a double logarithm of the ratio of the squared transverse momenta of the reggeized gluons. We discuss how these additional terms improve the collinear convergence of the whole approach and reduce the asymptotic growth with energy of cross sections. Taking advantage of the Monte Carlo implementation, we show how the new results reduce the diffusion of the gluon ladder into infrared and ultraviolet transverse momentum scales, while strongly affecting final state configurations by reducing the mini-jet multiplicity.
2303.05182
Vadim Guzey
V. Guzey (Jyvaskyla U. and Helsinki U.), M. Klasen (Munster U., ITP)
Inclusive and diffractive dijet photoproduction at the Electron-Ion Collider in NLO QCD
10 pages, 5 figures. Contribution to Proceedings of XXIX Cracow EPIPHANY Conference on Physics at the Electron-Ion Collider and Future Facilities, Cracow, Poland, January 16-19, 2023
null
null
MS-TP-23-08
hep-ph hep-ex nucl-ex
http://creativecommons.org/licenses/by/4.0/
In the framework of collinear factorization and next-to-leading order (NLO) perturbative QCD, we make predictions for inclusive and diffractive dijet photoproduction in electron-proton and electron-nucleus scattering in the EIC kinematics. We establish kinematic ranges in the ${\bar p}_T$, ${\bar \eta}$, $x_A^{\rm obs}$ and $x_{\gamma}^{\rm obs}$ variables, quantify sensitivity to small-$x$ nuclear PDFs, and analyze various scenarios of factorization breaking in the case of diffractive scattering.
[ { "created": "Thu, 9 Mar 2023 11:21:56 GMT", "version": "v1" }, { "created": "Mon, 20 Mar 2023 08:43:36 GMT", "version": "v2" } ]
2023-03-21
[ [ "Guzey", "V.", "", "Jyvaskyla U. and Helsinki U." ], [ "Klasen", "M.", "", "Munster U., ITP" ] ]
In the framework of collinear factorization and next-to-leading order (NLO) perturbative QCD, we make predictions for inclusive and diffractive dijet photoproduction in electron-proton and electron-nucleus scattering in the EIC kinematics. We establish kinematic ranges in the ${\bar p}_T$, ${\bar \eta}$, $x_A^{\rm obs}$ and $x_{\gamma}^{\rm obs}$ variables, quantify sensitivity to small-$x$ nuclear PDFs, and analyze various scenarios of factorization breaking in the case of diffractive scattering.
1308.6828
Bob Holdom
B. Holdom
Soft asymptotics with mass gap
10 pages, 4 figures, improved discussion, version to appear in Physics Letters B
Physics Letters B728 (2014) 467
10.1016/j.physletb.2013.12.017
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
From the operator product expansion the gluon condensate controls a certain power law correction to the ultraviolet behavior of the gauge theory. This is reflected by the asymptotic behavior of the effective gluon mass function as determined by its Schwinger-Dyson equation. We show that the current state of the art determination of the gluon mass function by Binosi, Ibanez and Papavassiliou points to a vanishing gluon condensate. If this is correct then the vacuum energy also vanishes in massless QCD. This result can be interpreted as a statement about a softness in the ultraviolet behavior and the consistency of this behavior with a mass gap.
[ { "created": "Fri, 30 Aug 2013 19:41:00 GMT", "version": "v1" }, { "created": "Thu, 5 Dec 2013 17:34:40 GMT", "version": "v2" } ]
2014-05-21
[ [ "Holdom", "B.", "" ] ]
From the operator product expansion the gluon condensate controls a certain power law correction to the ultraviolet behavior of the gauge theory. This is reflected by the asymptotic behavior of the effective gluon mass function as determined by its Schwinger-Dyson equation. We show that the current state of the art determination of the gluon mass function by Binosi, Ibanez and Papavassiliou points to a vanishing gluon condensate. If this is correct then the vacuum energy also vanishes in massless QCD. This result can be interpreted as a statement about a softness in the ultraviolet behavior and the consistency of this behavior with a mass gap.
1103.1269
Vladimir Braun M
V.M. Braun, T. Lautenschlager, A.N. Manashov and B. Pirnay
Higher twist parton distributions from light-cone wave functions
22 pages, 11 figures
Phys.Rev.D83:094023,2011
10.1103/PhysRevD.83.094023
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the possibility to construct higher-twist parton distributions in a nucleon at some low reference scale from convolution integrals of the light-cone wave functions (WFs). To this end we introduce simple models for the four-particle nucleon WFs involving three valence quarks and a gluon with total orbital momentum zero, and estimate their normalization (WF at the origin) using QCD sum rules. We demonstrate that these WFs provide one with a reasonable description of both polarized and unpolarized gluon parton densities at large values of Bjorken variable x > 0.5. Twist-three parton distributions are then constructed as convolution integrals of qqqg and usual three-quark WFs. The cases of the polarized structure function g_2(x,Q^2) and single transverse spin asymmetries are considered in detail. We find that the so-called gluon-pole contribution to twist-three distributions relevant for single spin asymmetry vanishes in this model, but is generated perturbatively at higher scales by the evolution, in the spirit of GRV parton distributions.
[ { "created": "Mon, 7 Mar 2011 13:32:20 GMT", "version": "v1" } ]
2011-07-08
[ [ "Braun", "V. M.", "" ], [ "Lautenschlager", "T.", "" ], [ "Manashov", "A. N.", "" ], [ "Pirnay", "B.", "" ] ]
We explore the possibility to construct higher-twist parton distributions in a nucleon at some low reference scale from convolution integrals of the light-cone wave functions (WFs). To this end we introduce simple models for the four-particle nucleon WFs involving three valence quarks and a gluon with total orbital momentum zero, and estimate their normalization (WF at the origin) using QCD sum rules. We demonstrate that these WFs provide one with a reasonable description of both polarized and unpolarized gluon parton densities at large values of Bjorken variable x > 0.5. Twist-three parton distributions are then constructed as convolution integrals of qqqg and usual three-quark WFs. The cases of the polarized structure function g_2(x,Q^2) and single transverse spin asymmetries are considered in detail. We find that the so-called gluon-pole contribution to twist-three distributions relevant for single spin asymmetry vanishes in this model, but is generated perturbatively at higher scales by the evolution, in the spirit of GRV parton distributions.
hep-ph/0112175
Ismd31
I.M. Dremin, P. Ed\'en
Parton and dipole approaches in QCD
6 pages, 1 figures in gif, talk given at XXXI International Symposium on Multiparticle Dynamics, Sept 1-7, 2001, Datong China. See http://ismd31.ccnu.edu.cn/
null
10.1142/9789812778048_0045
null
hep-ph
null
Here, we discuss QCD predictions on multiplicities in parton and dipole approaches. The most general treatment is based on the notion of the generating functions. The generating function G is defined as $G(u,y)=\sum_nu^nP_n(y)$, where $P_n$ is the probability of the n-particle production at energy denoted by y, u is an auxiliary variable. The mean multiplicity and higher moments of the multiplicity distribution $P_n$ are given by the u-derivatives of G at u=1.
[ { "created": "Thu, 13 Dec 2001 09:08:24 GMT", "version": "v1" } ]
2017-08-23
[ [ "Dremin", "I. M.", "" ], [ "Edén", "P.", "" ] ]
Here, we discuss QCD predictions on multiplicities in parton and dipole approaches. The most general treatment is based on the notion of the generating functions. The generating function G is defined as $G(u,y)=\sum_nu^nP_n(y)$, where $P_n$ is the probability of the n-particle production at energy denoted by y, u is an auxiliary variable. The mean multiplicity and higher moments of the multiplicity distribution $P_n$ are given by the u-derivatives of G at u=1.
hep-ph/9805219
Ernest Ma
Ernest Ma (UC Riverside)
Pathways to Naturally Small Neutrino Masses
12 pages including 5 figures; corrected minus signs in Eqs.(5)-(6), no result is affected
Phys.Rev.Lett.81:1171-1174,1998
10.1103/PhysRevLett.81.1171
UCRHEP-T222 (April 1998)
hep-ph
null
In the minimal standard electroweak gauge model, there is an effective dimension-five operator which generates neutrino masses, and it has only three tree-level realizations. One is the canonical seesaw mechanism with a right-handed neutrino. Another is having a heavy Higgs triplet as recently proposed. The third is to have a heavy Majorana fermion triplet, an example of which is presented here in the context of supersymmetric SU(5) grand unification. The three generic one-loop realizations of this operator are also discussed.
[ { "created": "Mon, 4 May 1998 20:21:26 GMT", "version": "v1" }, { "created": "Wed, 6 May 1998 00:14:01 GMT", "version": "v2" }, { "created": "Fri, 22 May 1998 18:02:05 GMT", "version": "v3" }, { "created": "Sat, 23 May 1998 15:53:59 GMT", "version": "v4" } ]
2008-11-26
[ [ "Ma", "Ernest", "", "UC Riverside" ] ]
In the minimal standard electroweak gauge model, there is an effective dimension-five operator which generates neutrino masses, and it has only three tree-level realizations. One is the canonical seesaw mechanism with a right-handed neutrino. Another is having a heavy Higgs triplet as recently proposed. The third is to have a heavy Majorana fermion triplet, an example of which is presented here in the context of supersymmetric SU(5) grand unification. The three generic one-loop realizations of this operator are also discussed.
2305.07075
Zhongtian Dong
Zhongtian Dong, Dorival Gon\c{c}alves, Kyoungchul Kong, Alberto Navarro
When the Machine Chimes the Bell: Entanglement and Bell Inequalities with Boosted $t\bar{t}$
12 pages, 6 figures, 2 tables. Updated to match with the published version
Phys. Rev. D (Vol. 109, No. 11), 2024
10.1103/PhysRevD.109.115023
null
hep-ph hep-ex quant-ph
http://creativecommons.org/licenses/by/4.0/
The Large Hadron Collider provides a unique opportunity to study quantum entanglement and violation of Bell inequalities at the highest energy available today. In this paper, we will investigate these quantum correlations with top quark pair production, which represents a system of two-qubits. The spacelike separation requirement for the two causally disconnected top quarks requires they fly relativistically away from each other, which motivates the use of the boosted top-tagging with the semi-leptonic top pair channel. Although measuring the spin polarization of the hadronic top quark is known to be challenging, our study indicates that it is feasible to reconstruct the spin density matrix of the two-qubit system using an optimal hadronic polarimeter. This is achieved with the aid of jet substructure techniques and NN-inspired reconstruction methods, which improve the mapping between subjets and quarks. We find that entanglement can already be observed at more than $5\sigma$ level with existing data, and violation of Bell inequalities may be probed above 4$\sigma$ level at the HL-LHC with 3 ab$^{-1}$ of data.
[ { "created": "Thu, 11 May 2023 18:24:21 GMT", "version": "v1" }, { "created": "Mon, 29 Jan 2024 21:08:16 GMT", "version": "v2" }, { "created": "Fri, 5 Jul 2024 15:34:34 GMT", "version": "v3" } ]
2024-07-08
[ [ "Dong", "Zhongtian", "" ], [ "Gonçalves", "Dorival", "" ], [ "Kong", "Kyoungchul", "" ], [ "Navarro", "Alberto", "" ] ]
The Large Hadron Collider provides a unique opportunity to study quantum entanglement and violation of Bell inequalities at the highest energy available today. In this paper, we will investigate these quantum correlations with top quark pair production, which represents a system of two-qubits. The spacelike separation requirement for the two causally disconnected top quarks requires they fly relativistically away from each other, which motivates the use of the boosted top-tagging with the semi-leptonic top pair channel. Although measuring the spin polarization of the hadronic top quark is known to be challenging, our study indicates that it is feasible to reconstruct the spin density matrix of the two-qubit system using an optimal hadronic polarimeter. This is achieved with the aid of jet substructure techniques and NN-inspired reconstruction methods, which improve the mapping between subjets and quarks. We find that entanglement can already be observed at more than $5\sigma$ level with existing data, and violation of Bell inequalities may be probed above 4$\sigma$ level at the HL-LHC with 3 ab$^{-1}$ of data.
hep-ph/9611269
null
G. Calucci, R. Ragazzon, D. Treleani
Rapidity gaps in minijets production at Tevatron energies
7 pages, TeX file, 2 figures; presented at XXVI Symposium on Multiparticle Dynamics FARO 1-5 September 1996
null
null
null
hep-ph
null
Multiparton interactions modify the high energy hadronic cross section to produce minijets with a rapidity gap in the distribution of secondaries. At Tevatron energy the correction to the single scattering term is large for transverse momenta smaller than 6 GeV.
[ { "created": "Thu, 7 Nov 1996 18:02:36 GMT", "version": "v1" } ]
2007-05-23
[ [ "Calucci", "G.", "" ], [ "Ragazzon", "R.", "" ], [ "Treleani", "D.", "" ] ]
Multiparton interactions modify the high energy hadronic cross section to produce minijets with a rapidity gap in the distribution of secondaries. At Tevatron energy the correction to the single scattering term is large for transverse momenta smaller than 6 GeV.
hep-ph/0205238
Thomas Dent
Thomas Dent (MCTP, University of Michigan)
CP from strings: ideas and problems
6 p., 1 epsfig, moriond.sty. Contribution to Moriond Electroweak Interactions and Unified Theories, 2002. Typos, discussion and ref.s added
null
null
null
hep-ph
null
CP has a natural embedding in superstring models as a gauge symmetry involving inversion of the compactified space. Hence the source of CP violation could be geometrical. Such models face the problem of how to suppress contributions to fermion electric dipole moments from softly-broken supersymmetry, as well as other problems of string phenomenology. Stringy symmetries are useful in evaluating models, and rule out some scenarios.
[ { "created": "Tue, 21 May 2002 19:59:18 GMT", "version": "v1" }, { "created": "Thu, 23 May 2002 14:09:27 GMT", "version": "v2" } ]
2007-05-23
[ [ "Dent", "Thomas", "", "MCTP, University of Michigan" ] ]
CP has a natural embedding in superstring models as a gauge symmetry involving inversion of the compactified space. Hence the source of CP violation could be geometrical. Such models face the problem of how to suppress contributions to fermion electric dipole moments from softly-broken supersymmetry, as well as other problems of string phenomenology. Stringy symmetries are useful in evaluating models, and rule out some scenarios.
hep-ph/9301205
null
John F. Gunion and Howard E. Haber
Errata for Higgs Bosons in Supersymmetric Models: I, II and III
4 pages, UCD-92-31 and SCIPP-92/59, PHYZZX format
null
null
null
hep-ph
null
Errata are given for J.F. Gunion and H.E. Haber, Nucl. Phys. B272 (1986) 1, Nucl. Phys. B278 (1986) 449, and Nucl. Phys. B307 (1988) 445.
[ { "created": "Tue, 5 Jan 1993 00:09:00 GMT", "version": "v1" } ]
2007-05-23
[ [ "Gunion", "John F.", "" ], [ "Haber", "Howard E.", "" ] ]
Errata are given for J.F. Gunion and H.E. Haber, Nucl. Phys. B272 (1986) 1, Nucl. Phys. B278 (1986) 449, and Nucl. Phys. B307 (1988) 445.
hep-ph/0004108
Gautam Bhattacharyya
Gautam Bhattacharyya, Subhendu Rakshit, Amitava Raychaudhuri
Cosmological constraints on R-parity violation from neutrino decay
13 pages, Latex, uses axodraw.sty; version to appear in Physical Review D
Phys.Rev. D62 (2000) 093007
10.1103/PhysRevD.62.093007
SINP/TNP/00-7, CUPP-00/2
hep-ph
null
If the neutrino mass is non-zero, as hinted by several experiments, then R-parity-violating supersymmetric Yukawa couplings can drive a heavy neutrino decay into lighter states. The heavy neutrino may either decay radiatively into a lighter neutrino, or it may decay into three light neutrinos through a Z-mediated penguin. For a given mass of the decaying neutrino, we calculate its lifetime for the various modes, each mode requiring certain pairs of R-parity-violating couplings be non-zero. We then check whether the calculated lifetimes fall in zones allowed or excluded by cosmological requirements. For the latter case, we derive stringent new constraints on the corresponding products of R-parity-violating couplings for given values of the decaying neutrino mass.
[ { "created": "Wed, 12 Apr 2000 09:54:17 GMT", "version": "v1" }, { "created": "Mon, 17 Apr 2000 09:55:15 GMT", "version": "v2" }, { "created": "Fri, 30 Jun 2000 17:27:21 GMT", "version": "v3" } ]
2009-10-31
[ [ "Bhattacharyya", "Gautam", "" ], [ "Rakshit", "Subhendu", "" ], [ "Raychaudhuri", "Amitava", "" ] ]
If the neutrino mass is non-zero, as hinted by several experiments, then R-parity-violating supersymmetric Yukawa couplings can drive a heavy neutrino decay into lighter states. The heavy neutrino may either decay radiatively into a lighter neutrino, or it may decay into three light neutrinos through a Z-mediated penguin. For a given mass of the decaying neutrino, we calculate its lifetime for the various modes, each mode requiring certain pairs of R-parity-violating couplings be non-zero. We then check whether the calculated lifetimes fall in zones allowed or excluded by cosmological requirements. For the latter case, we derive stringent new constraints on the corresponding products of R-parity-violating couplings for given values of the decaying neutrino mass.
1103.2757
Gustavo Marques Tavares
Zoltan Ligeti, Gustavo Marques Tavares, Martin Schmaltz
Explaining the t tbar forward-backward asymmetry without dijet or flavor anomalies
7 pages, 6 figures; v2: notation clarified, references added
null
10.1007/JHEP06(2011)109
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider new physics explanations of the anomaly in the top quark forward-backward asymmetry measured at the Tevatron, in the context of flavor conserving models. The recently measured LHC dijet distributions strongly constrain many otherwise viable models. A new scalar particle in the antitriplet representation of flavor and color can fit the t tbar asymmetry and cross section data at the Tevatron and avoid both low- and high-energy bounds from flavor physics and the LHC. An s-channel resonance in uc to uc scattering at the LHC is predicted to be not far from the current sensitivity. This model also predicts rich top quark physics for the early LHC from decays of the new scalar particles. Single production gives t tbar j signatures with high transverse momentum jet, pair production leads to t tbar j j and 4 jet final states.
[ { "created": "Mon, 14 Mar 2011 19:48:42 GMT", "version": "v1" }, { "created": "Mon, 28 Mar 2011 18:17:30 GMT", "version": "v2" } ]
2015-05-27
[ [ "Ligeti", "Zoltan", "" ], [ "Tavares", "Gustavo Marques", "" ], [ "Schmaltz", "Martin", "" ] ]
We consider new physics explanations of the anomaly in the top quark forward-backward asymmetry measured at the Tevatron, in the context of flavor conserving models. The recently measured LHC dijet distributions strongly constrain many otherwise viable models. A new scalar particle in the antitriplet representation of flavor and color can fit the t tbar asymmetry and cross section data at the Tevatron and avoid both low- and high-energy bounds from flavor physics and the LHC. An s-channel resonance in uc to uc scattering at the LHC is predicted to be not far from the current sensitivity. This model also predicts rich top quark physics for the early LHC from decays of the new scalar particles. Single production gives t tbar j signatures with high transverse momentum jet, pair production leads to t tbar j j and 4 jet final states.
2408.01123
Alex Keshavarzi
Luca Di Luzio, Alexander Keshavarzi, Antonio Masiero, Paride Paradisi
Model Independent Tests of the Hadronic Vacuum Polarization Contribution to the Muon $g$$-$$2$
8 pages, 2 figures
null
null
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The hadronic vacuum polarization (HVP) contributions to the muon $g$$-$$2$ are the crucial quantity to resolve whether new physics is present or not in the comparison between the Standard Model (SM) prediction and experimental measurements at Fermilab. They are commonly and historically determined via dispersion relations using a vast catalogue of experimentally measured, low-energy $e^+e^-\to \,\rm{hadrons}$ cross section data as input. These dispersive estimates result in a SM prediction that exhibits a muon $g$$-$$2$ discrepancy of more than $5\sigma$ when compared to experiment. However, recent lattice QCD evaluations of the HVP and a new hadronic cross section measurement from the CMD-3 experiment favor a no-new-physics scenario and, therefore, exhibit a common tension with the previous $e^+e^-\to \,\rm{hadrons}$ data. This study explores the current and future implications of these two scenarios on other observables that are also sensitive to the HVP contributions in the hope that they may provide independent tests of the current tensions observed in the muon $g$$-$$2$.
[ { "created": "Fri, 2 Aug 2024 09:06:58 GMT", "version": "v1" } ]
2024-08-05
[ [ "Di Luzio", "Luca", "" ], [ "Keshavarzi", "Alexander", "" ], [ "Masiero", "Antonio", "" ], [ "Paradisi", "Paride", "" ] ]
The hadronic vacuum polarization (HVP) contributions to the muon $g$$-$$2$ are the crucial quantity to resolve whether new physics is present or not in the comparison between the Standard Model (SM) prediction and experimental measurements at Fermilab. They are commonly and historically determined via dispersion relations using a vast catalogue of experimentally measured, low-energy $e^+e^-\to \,\rm{hadrons}$ cross section data as input. These dispersive estimates result in a SM prediction that exhibits a muon $g$$-$$2$ discrepancy of more than $5\sigma$ when compared to experiment. However, recent lattice QCD evaluations of the HVP and a new hadronic cross section measurement from the CMD-3 experiment favor a no-new-physics scenario and, therefore, exhibit a common tension with the previous $e^+e^-\to \,\rm{hadrons}$ data. This study explores the current and future implications of these two scenarios on other observables that are also sensitive to the HVP contributions in the hope that they may provide independent tests of the current tensions observed in the muon $g$$-$$2$.
2002.06686
Ulrich Nierste
Ulrich Nierste
Charm decays
Talk at "Beauty 2019", 29 September -- 4 October 2019, Ljubljana, Slovenia, 10 pages, 4 figures
null
null
TTP20-009
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I discuss hadronic decays of $D$ mesons with emphasis on the recent discovery of charm CP violation in $D^0\to K^+K^-,\pi^+\pi^-$ decays. The measured difference $\Delta a_{CP} \, \equiv \; a_{CP}^{\mathrm{dir}}(D^0\rightarrow K^+K^-) - a_{CP}^{\mathrm{dir}}(D^0\rightarrow\pi^+\pi^-) = \; (-15.4\pm 2.9)\cdot 10^{-4}$ of two direct CP asymmetries exceeds the SM prediction by a factor of 7. A possible explanation is an enhancement of the penguin amplitude entering $ a_{CP}^{\mathrm{dir}}$ by QCD effects which are not understood yet. Alternatively, $\Delta a_{CP}$ could be dominated by contributions from new physics. In order to distinguish these two hypotheses further CP asymmetries should be measured. To this end CP asymmetries resulting from the interference of two tree-level amplitudes auch as $a_{CP}^{\mathrm{dir}}(D^0\rightarrow K_SK_S)$ or $a_{CP}^{\mathrm{dir}}(D^0 \to K^{*0} K_S)$ are especially interesting.
[ { "created": "Sun, 16 Feb 2020 21:40:33 GMT", "version": "v1" } ]
2020-02-18
[ [ "Nierste", "Ulrich", "" ] ]
I discuss hadronic decays of $D$ mesons with emphasis on the recent discovery of charm CP violation in $D^0\to K^+K^-,\pi^+\pi^-$ decays. The measured difference $\Delta a_{CP} \, \equiv \; a_{CP}^{\mathrm{dir}}(D^0\rightarrow K^+K^-) - a_{CP}^{\mathrm{dir}}(D^0\rightarrow\pi^+\pi^-) = \; (-15.4\pm 2.9)\cdot 10^{-4}$ of two direct CP asymmetries exceeds the SM prediction by a factor of 7. A possible explanation is an enhancement of the penguin amplitude entering $ a_{CP}^{\mathrm{dir}}$ by QCD effects which are not understood yet. Alternatively, $\Delta a_{CP}$ could be dominated by contributions from new physics. In order to distinguish these two hypotheses further CP asymmetries should be measured. To this end CP asymmetries resulting from the interference of two tree-level amplitudes auch as $a_{CP}^{\mathrm{dir}}(D^0\rightarrow K_SK_S)$ or $a_{CP}^{\mathrm{dir}}(D^0 \to K^{*0} K_S)$ are especially interesting.
0704.3153
Zhi-Zhong Xing
Aik Hui Chan, Harald Fritzsch, Shu Luo, Zhi-zhong Xing
Deviations from Tri-bimaximal Neutrino Mixing in Type-II Seesaw and Leptogenesis
RevTeX 14 pages, 2 figures. Title and authors changed, and discussions on the minimal type-II seesaw and leptogenesis added. Accepted for publication in Phys. Rev. D
Phys.Rev.D76:073009,2007
10.1103/PhysRevD.76.073009
null
hep-ph
null
Current experimental data allow the zero value for one neutrino mass, either m_1 = 0 or m_3 = 0. This observation implies that a realistic neutrino mass texture can be established by starting from the limit (a) m_1 = m_2 = 0 and m_3 \neq 0 or (b) m_1 = m_2 \neq 0 and m_3 = 0. In both cases, we may introduce a particular perturbation which ensures the resultant neutrino mixing matrix to be the tri-bimaximal mixing pattern or its viable variations with all entries being formed from small integers and their square roots. We find that it is natural to incorporate this kind of neutrino mass matrix in the minimal Type-II seesaw model with only one heavy right-handed Majorana neutrino N in addition to the SU(2)_L Higgs triplet \Delta_L. We show that it is possible to account for the cosmological baryon number asymmetry in the m_3 =0 case via thermal leptogenesis, in which the one-loop vertex correction to N decays is mediated by \Delta_L and the CP-violating asymmetry of N decays is attributed to the electron flavor.
[ { "created": "Tue, 24 Apr 2007 10:08:25 GMT", "version": "v1" }, { "created": "Wed, 5 Sep 2007 10:28:03 GMT", "version": "v2" } ]
2008-11-26
[ [ "Chan", "Aik Hui", "" ], [ "Fritzsch", "Harald", "" ], [ "Luo", "Shu", "" ], [ "Xing", "Zhi-zhong", "" ] ]
Current experimental data allow the zero value for one neutrino mass, either m_1 = 0 or m_3 = 0. This observation implies that a realistic neutrino mass texture can be established by starting from the limit (a) m_1 = m_2 = 0 and m_3 \neq 0 or (b) m_1 = m_2 \neq 0 and m_3 = 0. In both cases, we may introduce a particular perturbation which ensures the resultant neutrino mixing matrix to be the tri-bimaximal mixing pattern or its viable variations with all entries being formed from small integers and their square roots. We find that it is natural to incorporate this kind of neutrino mass matrix in the minimal Type-II seesaw model with only one heavy right-handed Majorana neutrino N in addition to the SU(2)_L Higgs triplet \Delta_L. We show that it is possible to account for the cosmological baryon number asymmetry in the m_3 =0 case via thermal leptogenesis, in which the one-loop vertex correction to N decays is mediated by \Delta_L and the CP-violating asymmetry of N decays is attributed to the electron flavor.
0907.0545
Masaaki Kuroda
Dieter Schildknecht
The Color-dipole Picture and FL
Presented at DIS2009, Madrid, April 25-30,2009
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The prediction of FL(x,Q2)=0.27F2(x,Q2) in the color-dipole picture based on color-transparency and transverse-size reduction, is consistent with the experimental results from HERA.
[ { "created": "Fri, 3 Jul 2009 06:59:00 GMT", "version": "v1" } ]
2009-07-06
[ [ "Schildknecht", "Dieter", "" ] ]
The prediction of FL(x,Q2)=0.27F2(x,Q2) in the color-dipole picture based on color-transparency and transverse-size reduction, is consistent with the experimental results from HERA.
1204.6251
Martin Hoferichter
M. Hoferichter, C. Ditsche, B. Kubis, U.-G. Mei{\ss}ner
Dispersive analysis of the scalar form factor of the nucleon
24 pages, 6 figures; version published in JHEP
JHEP 1206:063,2012
10.1007/JHEP06(2012)063
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Based on the recently proposed Roy-Steiner equations for pion-nucleon scattering, we derive a system of coupled integral equations for the pi pi --> N-bar N and K-bar K --> N-bar N S-waves. These equations take the form of a two-channel Muskhelishvili-Omnes problem, whose solution in the presence of a finite matching point is discussed. We use these results to update the dispersive analysis of the scalar form factor of the nucleon fully including K-bar K intermediate states. In particular, we determine the correction Delta_sigma=sigma(2M_pi^2)-sigma_{pi N}, which is needed for the extraction of the pion-nucleon sigma term from pi N scattering, as a function of pion-nucleon subthreshold parameters and the pi N coupling constant.
[ { "created": "Fri, 27 Apr 2012 15:40:12 GMT", "version": "v1" }, { "created": "Tue, 12 Jun 2012 12:09:03 GMT", "version": "v2" } ]
2012-06-13
[ [ "Hoferichter", "M.", "" ], [ "Ditsche", "C.", "" ], [ "Kubis", "B.", "" ], [ "Meißner", "U. -G.", "" ] ]
Based on the recently proposed Roy-Steiner equations for pion-nucleon scattering, we derive a system of coupled integral equations for the pi pi --> N-bar N and K-bar K --> N-bar N S-waves. These equations take the form of a two-channel Muskhelishvili-Omnes problem, whose solution in the presence of a finite matching point is discussed. We use these results to update the dispersive analysis of the scalar form factor of the nucleon fully including K-bar K intermediate states. In particular, we determine the correction Delta_sigma=sigma(2M_pi^2)-sigma_{pi N}, which is needed for the extraction of the pion-nucleon sigma term from pi N scattering, as a function of pion-nucleon subthreshold parameters and the pi N coupling constant.
1805.08591
Roman Ryutin Dr
R.A. Ryutin
ExDiff Monte Carlo generator for Exclusive Diffraction. Version 2.0. Physics and manual
34 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:1704.04387
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
ExDiff2.0 is a Monte Carlo event generator for simulation of Exclusive Diffractive processes in proton-proton collisions. The present version includes reactions: elastic scattering $pp\to pp$ at 7, 8, 13, 14~TeV; $pp\to p+R+p$, $R = f_0(1500)$, $f_0(1710)$, $f_2(1950)$ at 8 and 13~TeV, $f_2(1270)$ at 8~TeV, $f_2(2220)$ at 13~TeV. In the future versions many processes of Central Exclusive Diffractive Production will be added. This version is linked to PYTHIA 8 (to make resonance decays and hadronization) and also to ROOT and HEPMC output via PYTHIA 8 interface. Also some test files of Born distributions for CEDP of two pions are added.
[ { "created": "Mon, 14 May 2018 11:12:12 GMT", "version": "v1" } ]
2018-05-23
[ [ "Ryutin", "R. A.", "" ] ]
ExDiff2.0 is a Monte Carlo event generator for simulation of Exclusive Diffractive processes in proton-proton collisions. The present version includes reactions: elastic scattering $pp\to pp$ at 7, 8, 13, 14~TeV; $pp\to p+R+p$, $R = f_0(1500)$, $f_0(1710)$, $f_2(1950)$ at 8 and 13~TeV, $f_2(1270)$ at 8~TeV, $f_2(2220)$ at 13~TeV. In the future versions many processes of Central Exclusive Diffractive Production will be added. This version is linked to PYTHIA 8 (to make resonance decays and hadronization) and also to ROOT and HEPMC output via PYTHIA 8 interface. Also some test files of Born distributions for CEDP of two pions are added.
1910.04761
Andreas Papaefstathiou
Andreas Papaefstathiou, Simon Pl\"atzer, Kazuki Sakurai
On the phenomenology of sphaleron-induced processes at the LHC and beyond
23 pages, 12 figures
null
10.1007/JHEP12(2019)017
Nikhef 2019-045, UWTHPH-2019-30, MCnet-19-23
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the phenomenological aspects of non-perturbative baryon- and lepton-number-violating processes at hadron colliders. Such processes, induced by instanton/sphaleron configurations of the electroweak gauge fields, are believed to play a crucial role in the generation of baryon asymmetry in the early Universe at finite temperature. On the other hand, at colliders (that represent the zero-temperature high-energy regime) the rate and observability of such processes are still under debate. Motivated by current theoretical considerations, we construct a modern event generator within the general-purpose Herwig Monte Carlo framework, that aims to capture the most relevant features of the dominant processes. We perform a detailed phenomenological analysis focussing on the Large Hadron Collider, at 13 TeV proton-proton centre-of-mass energy, a potential high-energy upgrade at 27 TeV and the proposed Future Circular Collider (FCC-hh) at 100 TeV. We derive constraints on the expected rates for various parametrisations of our model. We find that all three colliders are capable of providing meaningful information on the nature of instanton/sphaleron-induced processes at various energy scales.
[ { "created": "Thu, 10 Oct 2019 18:00:00 GMT", "version": "v1" } ]
2020-01-29
[ [ "Papaefstathiou", "Andreas", "" ], [ "Plätzer", "Simon", "" ], [ "Sakurai", "Kazuki", "" ] ]
We investigate the phenomenological aspects of non-perturbative baryon- and lepton-number-violating processes at hadron colliders. Such processes, induced by instanton/sphaleron configurations of the electroweak gauge fields, are believed to play a crucial role in the generation of baryon asymmetry in the early Universe at finite temperature. On the other hand, at colliders (that represent the zero-temperature high-energy regime) the rate and observability of such processes are still under debate. Motivated by current theoretical considerations, we construct a modern event generator within the general-purpose Herwig Monte Carlo framework, that aims to capture the most relevant features of the dominant processes. We perform a detailed phenomenological analysis focussing on the Large Hadron Collider, at 13 TeV proton-proton centre-of-mass energy, a potential high-energy upgrade at 27 TeV and the proposed Future Circular Collider (FCC-hh) at 100 TeV. We derive constraints on the expected rates for various parametrisations of our model. We find that all three colliders are capable of providing meaningful information on the nature of instanton/sphaleron-induced processes at various energy scales.
2203.13403
Stefano Profumo
Logan Morrison, Stefano Profumo, Nolan Smyth, John Tamanas
Simulation Based Inference for Efficient Theory Space Sampling: an Application to Supersymmetric Explanations of the Anomalous Muon (g-2)
10 pages, 7 figures, version to appear in Phys. Rev. D
Physical Review D, Vol. 106, No. 11 (2022)
10.1103/PhysRevD.106.115016
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
For the purpose of minimizing the number of sample model evaluations, we propose and study algorithms that utilize (sequential) versions of likelihood-to-evidence ratio neural estimation.We apply our algorithms to a supersymmetric interpretation of the anomalous muon magnetic dipole moment in the context of a phenomenological minimal supersymmetric extension of the standard model, and recover non-trivial models in an experimentally-constrained theory space. Finally we summarize further potential possible uses of these algorithms in future studies.
[ { "created": "Fri, 25 Mar 2022 01:11:06 GMT", "version": "v1" }, { "created": "Sat, 3 Dec 2022 23:08:27 GMT", "version": "v2" } ]
2022-12-15
[ [ "Morrison", "Logan", "" ], [ "Profumo", "Stefano", "" ], [ "Smyth", "Nolan", "" ], [ "Tamanas", "John", "" ] ]
For the purpose of minimizing the number of sample model evaluations, we propose and study algorithms that utilize (sequential) versions of likelihood-to-evidence ratio neural estimation.We apply our algorithms to a supersymmetric interpretation of the anomalous muon magnetic dipole moment in the context of a phenomenological minimal supersymmetric extension of the standard model, and recover non-trivial models in an experimentally-constrained theory space. Finally we summarize further potential possible uses of these algorithms in future studies.
2211.08103
Liang Zheng
Lian Liu, Zhong-Bao Yin, Liang Zheng
The universal scaling of kinetic freeze-out parameters across different collision systems at the LHC energy
15 pages, 8 figures
Chinese Physics C Vol. 47, No. 2 (2023) 024103
10.1088/1674-1137/aca38d
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
In this paper, we perform the Tsallis Blast-Wave analysis on the transverse momentum spectra of identified hadrons produced in a wide range of collision systems at the Large Hadron Collider (LHC) including pp, pPb, XeXe and PbPb collisions. The kinetic freeze-out properties are investigated across these systems varying with the event multiplicity. We find that the extracted kinetic freeze-out temperature, radial flow velocity and the non-extensive parameter exhibit a universal scaling behavior for these systems with very different geometric size, especially when the independent baryon Tsallis non-extensive parameter is considered. This universality may indicate the existence of a unified partonic evolution stage in different collision systems at the LHC energies.
[ { "created": "Tue, 15 Nov 2022 12:49:37 GMT", "version": "v1" }, { "created": "Sat, 6 May 2023 13:16:25 GMT", "version": "v2" } ]
2023-05-09
[ [ "Liu", "Lian", "" ], [ "Yin", "Zhong-Bao", "" ], [ "Zheng", "Liang", "" ] ]
In this paper, we perform the Tsallis Blast-Wave analysis on the transverse momentum spectra of identified hadrons produced in a wide range of collision systems at the Large Hadron Collider (LHC) including pp, pPb, XeXe and PbPb collisions. The kinetic freeze-out properties are investigated across these systems varying with the event multiplicity. We find that the extracted kinetic freeze-out temperature, radial flow velocity and the non-extensive parameter exhibit a universal scaling behavior for these systems with very different geometric size, especially when the independent baryon Tsallis non-extensive parameter is considered. This universality may indicate the existence of a unified partonic evolution stage in different collision systems at the LHC energies.
1912.02197
Maximilian Ruhdorfer
Csaba Csaki, Maximilian Ruhdorfer, and Yuri Shirman
UV Sensitivity of the Axion Mass from Instantons in Partially Broken Gauge Groups
30 pages, LaTeX, 4 figures; v2: minor modifications, references added
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the contribution of small instantons to the axion mass in various UV completions of QCD. We show that the reason behind the potential dominance of such contributions is the non-trivial embedding of QCD into the UV theory. The effects from instantons in the partially broken gauge group appear as "fractional instanton" corrections in the effective theory. These will exhibit unusual dependences on the various scales in the problem whenever the index of embedding is non-trivial. We present a full one-instanton calculation of the axion mass in the simplest product group models, carefully keeping track of numerical prefactors. Rather than using a 't Hooft operator approximation we directly evaluate the contributions to the vacuum bubble, automatically capturing the effects of closing up external fermion lines with Higgs loops. This approach is manifestly finite and removes the uncertainty associated with introducing a cutoff scale for the Higgs loops. We verify that the small instantons may dominate over the QCD contribution for very high breaking scales and at least three group factors.
[ { "created": "Wed, 4 Dec 2019 19:00:04 GMT", "version": "v1" }, { "created": "Tue, 18 Feb 2020 08:36:15 GMT", "version": "v2" } ]
2020-02-19
[ [ "Csaki", "Csaba", "" ], [ "Ruhdorfer", "Maximilian", "" ], [ "Shirman", "Yuri", "" ] ]
We examine the contribution of small instantons to the axion mass in various UV completions of QCD. We show that the reason behind the potential dominance of such contributions is the non-trivial embedding of QCD into the UV theory. The effects from instantons in the partially broken gauge group appear as "fractional instanton" corrections in the effective theory. These will exhibit unusual dependences on the various scales in the problem whenever the index of embedding is non-trivial. We present a full one-instanton calculation of the axion mass in the simplest product group models, carefully keeping track of numerical prefactors. Rather than using a 't Hooft operator approximation we directly evaluate the contributions to the vacuum bubble, automatically capturing the effects of closing up external fermion lines with Higgs loops. This approach is manifestly finite and removes the uncertainty associated with introducing a cutoff scale for the Higgs loops. We verify that the small instantons may dominate over the QCD contribution for very high breaking scales and at least three group factors.
1702.07885
Monojit Ghosh
Monojit Ghosh
Why T2K should run in dominant neutrino mode to discover CP violation ?
3 pages, 3 figures, Prepared for the proceedings of XXII DAE-BRNS High Energy Physics Symposium, University of Delhi, India, 12-16 December, 2016
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The first hint of the leptonic CP phase $\delta_{CP}=-90^\circ$ has already came from the long-baseline neutrino oscillation experiment T2K. This hint is derived from the neutrino data of T2K and currently it is running in the antineutrino mode. In this work we ask the question what should be the proportion of neutrino and antineutrino running of the T2K experiment to discover CP violation in the leptonic sector.
[ { "created": "Sat, 25 Feb 2017 12:51:38 GMT", "version": "v1" } ]
2017-02-28
[ [ "Ghosh", "Monojit", "" ] ]
The first hint of the leptonic CP phase $\delta_{CP}=-90^\circ$ has already came from the long-baseline neutrino oscillation experiment T2K. This hint is derived from the neutrino data of T2K and currently it is running in the antineutrino mode. In this work we ask the question what should be the proportion of neutrino and antineutrino running of the T2K experiment to discover CP violation in the leptonic sector.
0901.4812
Kentaro Kojima
Kentaro Kojima and Hideyuki Sawanaka
Probing neutrino masses and tri-bimaximality with lepton flavor violation searches
17 pages, references and clarifications added, typos corrected
Phys.Lett.B678:373-379,2009
10.1016/j.physletb.2009.06.046
KYUSHU-HET-116
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine relation between neutrino oscillation parameters and prediction of lepton flavor violation, in light of deviations from tri-bimaximal mixing. Our study shows that upcoming experimental searches for lepton flavor violation process can provide useful implications for neutrino mass spectrum and mixing angles. With simple structure of heavy right-handed neutrino and supersymmetry breaking sectors, the discovery of tau \to mu gamma decay determines neutrino mass hierarchy if large (order 0.1) reactor angle is established.
[ { "created": "Fri, 30 Jan 2009 12:19:55 GMT", "version": "v1" }, { "created": "Mon, 9 Feb 2009 12:34:33 GMT", "version": "v2" }, { "created": "Tue, 14 Jul 2009 02:54:13 GMT", "version": "v3" } ]
2010-04-15
[ [ "Kojima", "Kentaro", "" ], [ "Sawanaka", "Hideyuki", "" ] ]
We examine relation between neutrino oscillation parameters and prediction of lepton flavor violation, in light of deviations from tri-bimaximal mixing. Our study shows that upcoming experimental searches for lepton flavor violation process can provide useful implications for neutrino mass spectrum and mixing angles. With simple structure of heavy right-handed neutrino and supersymmetry breaking sectors, the discovery of tau \to mu gamma decay determines neutrino mass hierarchy if large (order 0.1) reactor angle is established.
1308.4025
Mariano Quiros
Luis Cort, Mateo Garcia and Mariano Quiros
Supersymmetric Custodial Triplets
33 pages, 9 figures. v2: Version to appear in PRD. Typos corrected and references added. Figs. 9 and 10 improved
Phys. Rev. D 88, 075010 (2013)
10.1103/PhysRevD.88.075010
UAB-FT-742
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the extension of the Minimal Supersymmetric Standard Model which includes extra Y=(0,\pm 1) supersymmetric triplets with a global SU(2)_L \otimes SU(2)_R symmetry spontaneousy broken to the custodial SU(2)_V by the vacuum expectation value of the neutral scalar components of doublets and triplets. The model is the supersymmetrization of the non-supersymmetric model introduced long ago by Georgi and Machacek where the \rho-parameter is kept to unity at the tree-level by the custodial symmetry. Accordingly the scalar sector is classified into degenerate SU(2)_V multiplets: singlets, triplets (including the one containing the Godstone bosons) and fiveplets. The singly and doubly charged chiral superfields play a key role in the unitarization of the theory. The couplings of the Standard Model-like Higgs to vector bosons (including \gamma\gamma) and fermions, and the corresponding Higgs signal strengths, are in agreement with LHC experimental data for a large region of the parameter space. Breaking of custodial invariance by radiative corrections suggests a low-scale mechanism of supersymmetry breaking.
[ { "created": "Mon, 19 Aug 2013 14:04:43 GMT", "version": "v1" }, { "created": "Mon, 14 Oct 2013 16:00:50 GMT", "version": "v2" } ]
2013-10-30
[ [ "Cort", "Luis", "" ], [ "Garcia", "Mateo", "" ], [ "Quiros", "Mariano", "" ] ]
We analyze the extension of the Minimal Supersymmetric Standard Model which includes extra Y=(0,\pm 1) supersymmetric triplets with a global SU(2)_L \otimes SU(2)_R symmetry spontaneousy broken to the custodial SU(2)_V by the vacuum expectation value of the neutral scalar components of doublets and triplets. The model is the supersymmetrization of the non-supersymmetric model introduced long ago by Georgi and Machacek where the \rho-parameter is kept to unity at the tree-level by the custodial symmetry. Accordingly the scalar sector is classified into degenerate SU(2)_V multiplets: singlets, triplets (including the one containing the Godstone bosons) and fiveplets. The singly and doubly charged chiral superfields play a key role in the unitarization of the theory. The couplings of the Standard Model-like Higgs to vector bosons (including \gamma\gamma) and fermions, and the corresponding Higgs signal strengths, are in agreement with LHC experimental data for a large region of the parameter space. Breaking of custodial invariance by radiative corrections suggests a low-scale mechanism of supersymmetry breaking.
hep-ph/9708363
Markus Thoma
Magaret E. Carrington, Hou Defu, Markus H. Thoma
Equilibrium and Non-Equilibrium Hard Thermal Loop Resummation in the Real Time Formalism
23 pages, REVTEX, 5 PostScript figures, revised version to be published in Eur. Phys. J. C
Eur.Phys.J.C7:347-354,1999
10.1007/s100520050412
UGI-97-12
hep-ph hep-th nucl-th
null
We investigate the use of the hard thermal loop (HTL) resummation technique in non-equilibrium field theory. We use the Keldysh representation of the real time formalism (RTF). We derive the HTL photon self energy and the resummed photon propagator. We show that no pinch singularities appear in the non-equilibrium HTL effective propagator. We discuss a possible regularization mechanism for these singularities at higher orders. As an example of the application of the HTL resummation method within the RTF we discuss the damping rate of a hard electron.
[ { "created": "Fri, 15 Aug 1997 11:27:46 GMT", "version": "v1" }, { "created": "Mon, 24 Aug 1998 14:36:10 GMT", "version": "v2" } ]
2011-09-13
[ [ "Carrington", "Magaret E.", "" ], [ "Defu", "Hou", "" ], [ "Thoma", "Markus H.", "" ] ]
We investigate the use of the hard thermal loop (HTL) resummation technique in non-equilibrium field theory. We use the Keldysh representation of the real time formalism (RTF). We derive the HTL photon self energy and the resummed photon propagator. We show that no pinch singularities appear in the non-equilibrium HTL effective propagator. We discuss a possible regularization mechanism for these singularities at higher orders. As an example of the application of the HTL resummation method within the RTF we discuss the damping rate of a hard electron.
0806.3174
Claude Semay
N. Boulanger, F. Buisseret, V. Mathieu, C. Semay
Constituent gluon interpretation of glueballs and gluelumps
3 figures, use of package youngtab
Eur.Phys.J.A38:317-330,2008
10.1140/epja/i2008-10675-5
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Arguments are given that support the interpretation of the lattice QCD glueball and gluelump spectra in terms of bound states of massless constituent gluons with helicity-1. In this scheme, the mass hierarchy of the currently known gluelumps and glueballs is mainly due to the number of constituent gluons and can be understood within a simple flux tube model. It is also argued that the lattice QCD $0^{+-}$ glueball should be seen as a four-gluon bound state. The flux tube model allows for a parameter-free computation of its mass, which is in good agreement with lattice QCD.
[ { "created": "Thu, 19 Jun 2008 11:34:02 GMT", "version": "v1" }, { "created": "Mon, 18 Aug 2008 07:22:14 GMT", "version": "v2" } ]
2008-12-18
[ [ "Boulanger", "N.", "" ], [ "Buisseret", "F.", "" ], [ "Mathieu", "V.", "" ], [ "Semay", "C.", "" ] ]
Arguments are given that support the interpretation of the lattice QCD glueball and gluelump spectra in terms of bound states of massless constituent gluons with helicity-1. In this scheme, the mass hierarchy of the currently known gluelumps and glueballs is mainly due to the number of constituent gluons and can be understood within a simple flux tube model. It is also argued that the lattice QCD $0^{+-}$ glueball should be seen as a four-gluon bound state. The flux tube model allows for a parameter-free computation of its mass, which is in good agreement with lattice QCD.
hep-ph/0508280
Hannes Jung
John Collins (Physics Department, Penn State University, USA), Hannes Jung (DESY, Hamburg, FRG)
Need for fully unintegrated parton densities
to appear in the proceedings of the HERA-LHC workshop (2004-2005)
null
null
null
hep-ph
null
Associated with the use of conventional integrated parton densities are kinematic approximations on parton momenta which result in unphysical differential distributions for final-state particles. We argue that it is important to reformulate perturbative QCD results in terms of fully unintegrated parton densities, differential in all components of the parton momentum.
[ { "created": "Sat, 27 Aug 2005 06:05:55 GMT", "version": "v1" } ]
2007-05-23
[ [ "Collins", "John", "", "Physics Department, Penn State University, USA" ], [ "Jung", "Hannes", "", "DESY, Hamburg, FRG" ] ]
Associated with the use of conventional integrated parton densities are kinematic approximations on parton momenta which result in unphysical differential distributions for final-state particles. We argue that it is important to reformulate perturbative QCD results in terms of fully unintegrated parton densities, differential in all components of the parton momentum.
hep-ph/0410011
Joaquim Matias
David London, Joaquim Matias and Javier Virto
Bd^0(t)->pi^+pi^- and Bs^0(t)-> K^+ K^- Decays: A Tool to Measure New-Physics Parameters
12 pages, 2 figures, LaTeX. Changed references
Phys.Rev. D71 (2005) 014024
10.1103/PhysRevD.71.014024
UdeM-GPP-TH-04-126,McGill 20/04,UAB-FT-573
hep-ph
null
If physics beyond the standard model is present in B decays, experimental measurements seem to suggest that it principally affects those processes with significant b->s penguin amplitudes. It was recently argued that, in general, such new-physics (NP) effects can be parametrized in terms of a single NP amplitude A^q and phase \Phi_q, for q=u,d,s,c. In this paper, we show that the study of the decays Bs(t) -> K^+ K^- and Bd(t) -> \pi^+\pi^- allows one to measure the NP parameters A^u and \Phi_u. We examine the implications for this method of the latest experimental results on these decays. If NP is found in Bs(t) -> K^+ K^-, it can be partially identified through measurements of Bs(t)-> K^0 \bar K^0.
[ { "created": "Fri, 1 Oct 2004 10:23:53 GMT", "version": "v1" }, { "created": "Thu, 13 Jan 2005 16:21:40 GMT", "version": "v2" } ]
2009-11-10
[ [ "London", "David", "" ], [ "Matias", "Joaquim", "" ], [ "Virto", "Javier", "" ] ]
If physics beyond the standard model is present in B decays, experimental measurements seem to suggest that it principally affects those processes with significant b->s penguin amplitudes. It was recently argued that, in general, such new-physics (NP) effects can be parametrized in terms of a single NP amplitude A^q and phase \Phi_q, for q=u,d,s,c. In this paper, we show that the study of the decays Bs(t) -> K^+ K^- and Bd(t) -> \pi^+\pi^- allows one to measure the NP parameters A^u and \Phi_u. We examine the implications for this method of the latest experimental results on these decays. If NP is found in Bs(t) -> K^+ K^-, it can be partially identified through measurements of Bs(t)-> K^0 \bar K^0.
2112.01992
Diego Teca Wellmann
Cesar Ayala, Gorazd Cvetic, Diego Teca
Using improved Operator Product Expansion in Borel-Laplace Sum Rules with ALEPH $\tau$ decay data, and determination of pQCD coupling
v3: 20 pages, 6 figures; corrected list of references
Eur.Phys.J.C82(2022)362
10.1140/epjc/s10052-022-10298-w
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use improved truncated Operator Product Expansion (OPE) for the Adler function, involving two types of terms with dimension $D=6$, in the double-pinched Borel-Laplace Sum Rules and Finite Energy Sum Rules for the V+A channel strangeless semihadronic $\tau$ decays. The generation of the higher order perturbative QCD terms of the $D=0$ part of the Adler function is carried out using a renormalon-motivated ansatz incorporating the leading UV renormalon and the first two leading IR renormalons. The trunacted $D=0$ part of the Sum Rules is evaluated by two variants of the fixed-order perturbation theory (FO), by Principal Value of the Borel resummation (PV), and by contour-improved perturbation theory (CI). For the experimental V+A channel spectral function we use the ALEPH $\tau$-decay data. We point out that the truncated FO and PV evaluation methods account correctly for the renormalon structure of the Sum Rules, while this is not the case for the truncated CI evaluation. We extract the value of the ${\overline {\rm MS}}$ coupling $\alpha_s(m_{\tau}^2) = 0.3235^{+0.0138}_{-0.0126}$ [$\alpha_s(M_Z^2)=0.1191 \pm 0.0016$] for the average of the two FO methods and the PV method, which we consider as our main result. If we included in the average also CI extraction, the value would be $\alpha_s(m_{\tau}^2) = 0.3299^{+0.0232}_{-0.0225}$ [$\alpha_s(M_Z^2)=0.1199^{+0.0026}_{-0.0028}$]. This work is an extension and improvement of our previous work [Eur.Phys.J.C81 (2021) 10, 930] where we used for the truncated OPE a more naive (and widely used) form and where the extracted values for $\alpha_s(M_Z^2)$ were somewhat lower.
[ { "created": "Fri, 3 Dec 2021 16:09:36 GMT", "version": "v1" }, { "created": "Tue, 1 Mar 2022 19:21:19 GMT", "version": "v2" }, { "created": "Mon, 2 May 2022 18:19:47 GMT", "version": "v3" } ]
2022-05-04
[ [ "Ayala", "Cesar", "" ], [ "Cvetic", "Gorazd", "" ], [ "Teca", "Diego", "" ] ]
We use improved truncated Operator Product Expansion (OPE) for the Adler function, involving two types of terms with dimension $D=6$, in the double-pinched Borel-Laplace Sum Rules and Finite Energy Sum Rules for the V+A channel strangeless semihadronic $\tau$ decays. The generation of the higher order perturbative QCD terms of the $D=0$ part of the Adler function is carried out using a renormalon-motivated ansatz incorporating the leading UV renormalon and the first two leading IR renormalons. The trunacted $D=0$ part of the Sum Rules is evaluated by two variants of the fixed-order perturbation theory (FO), by Principal Value of the Borel resummation (PV), and by contour-improved perturbation theory (CI). For the experimental V+A channel spectral function we use the ALEPH $\tau$-decay data. We point out that the truncated FO and PV evaluation methods account correctly for the renormalon structure of the Sum Rules, while this is not the case for the truncated CI evaluation. We extract the value of the ${\overline {\rm MS}}$ coupling $\alpha_s(m_{\tau}^2) = 0.3235^{+0.0138}_{-0.0126}$ [$\alpha_s(M_Z^2)=0.1191 \pm 0.0016$] for the average of the two FO methods and the PV method, which we consider as our main result. If we included in the average also CI extraction, the value would be $\alpha_s(m_{\tau}^2) = 0.3299^{+0.0232}_{-0.0225}$ [$\alpha_s(M_Z^2)=0.1199^{+0.0026}_{-0.0028}$]. This work is an extension and improvement of our previous work [Eur.Phys.J.C81 (2021) 10, 930] where we used for the truncated OPE a more naive (and widely used) form and where the extracted values for $\alpha_s(M_Z^2)$ were somewhat lower.
1208.2010
Victo Dos Santos Filho
Edson O. da Silva, J. P. B. C. de Melo, Victo S. Filho and Bruno El-Bennich
The Electromagnetic Form Factor of the Kaon in the Light-Front Approach
Paper with 4 pages, 1 figure, reference: XII HADRON PHYSICS Conference - to appear in AIP Conference Proceedings
null
10.1063/1.4796029
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The kaon electromagnetic form factor is calculated within a light-front constituent quark model (LFCQM). The electromagnetic components of the current are extracted from the Feynman triangle diagram within the light-front approach. We also obtain the electroweak decay constant and the charge radius for the kaon in the light-front approach. In this work, the kaon observables are calculated and a fairly good agreement is obtained with a very higher accuracy when compared with the experimental data.
[ { "created": "Thu, 9 Aug 2012 19:19:47 GMT", "version": "v1" }, { "created": "Wed, 20 Feb 2013 15:37:37 GMT", "version": "v2" } ]
2015-06-11
[ [ "da Silva", "Edson O.", "" ], [ "de Melo", "J. P. B. C.", "" ], [ "Filho", "Victo S.", "" ], [ "El-Bennich", "Bruno", "" ] ]
The kaon electromagnetic form factor is calculated within a light-front constituent quark model (LFCQM). The electromagnetic components of the current are extracted from the Feynman triangle diagram within the light-front approach. We also obtain the electroweak decay constant and the charge radius for the kaon in the light-front approach. In this work, the kaon observables are calculated and a fairly good agreement is obtained with a very higher accuracy when compared with the experimental data.
hep-ph/0503234
Francesco Caravaglios
Francesco Caravaglios and Stefano Morisi
Neutrino masses and mixings with an S3 family permutation symmetry
6 pages
null
null
ifum-832-ft
hep-ph
null
Large neutrino mixing angles suggest that the Yukawa sector is invariant under permutations of the fermion families. This S_{3} permutation symmetry is broken at a large energy scale but much below the unification scale. Assuming that the lepton mass matrix is approximately diagonal, all neutrino mixing angles naturally come from the breaking of S_{3}-> S_{2}. In the neutrino sector, S_{2} remains (approximately) unbroken. As a consequence, we have a large atmospheric neutrino angle and U_{e3}=0. The S_{3} symmetry at the unification scale can also explain the large solar mixing angle. We give an explicit expression of the solar mixing angle in terms of the left-handed neutrino masses. We observe that this family permutation symmetry comes very naturally from a quantized theory of functionals [1], that is an extension of quantum field theory.
[ { "created": "Wed, 23 Mar 2005 11:13:58 GMT", "version": "v1" }, { "created": "Thu, 24 Mar 2005 11:34:30 GMT", "version": "v2" } ]
2007-05-23
[ [ "Caravaglios", "Francesco", "" ], [ "Morisi", "Stefano", "" ] ]
Large neutrino mixing angles suggest that the Yukawa sector is invariant under permutations of the fermion families. This S_{3} permutation symmetry is broken at a large energy scale but much below the unification scale. Assuming that the lepton mass matrix is approximately diagonal, all neutrino mixing angles naturally come from the breaking of S_{3}-> S_{2}. In the neutrino sector, S_{2} remains (approximately) unbroken. As a consequence, we have a large atmospheric neutrino angle and U_{e3}=0. The S_{3} symmetry at the unification scale can also explain the large solar mixing angle. We give an explicit expression of the solar mixing angle in terms of the left-handed neutrino masses. We observe that this family permutation symmetry comes very naturally from a quantized theory of functionals [1], that is an extension of quantum field theory.
hep-ph/9706201
Alessandro
Elena Accomando, Alessandro Ballestrero and Marco Pizzio
Semileptonic six fermion processes at future $e^+ e^-$ colliders: signal and irreducible background for top and WWZ physics
28 pages including 8 figures (7 ps). Latex. Uses Axodraw. Minor changes and some typos corrected
Nucl.Phys. B512 (1998) 19-41
10.1016/S0550-3213(97)00745-1
DFTT 74/96
hep-ph
null
We compute several total and differential cross sections relevant to top and WWZ physics at future $e^+e^-$ colliders taking into account the full set of Feynman diagrams for six fermion final states. We also include in our calculations initial state radiation and beamstrahlung effects, and the most important QCD corrections in an approximate (naive) form. We compare such a complete approach with "production x decay" approximation and we suggest that in many physical studies the former is needed.
[ { "created": "Mon, 2 Jun 1997 16:26:20 GMT", "version": "v1" }, { "created": "Mon, 9 Jun 1997 17:08:58 GMT", "version": "v2" } ]
2009-10-30
[ [ "Accomando", "Elena", "" ], [ "Ballestrero", "Alessandro", "" ], [ "Pizzio", "Marco", "" ] ]
We compute several total and differential cross sections relevant to top and WWZ physics at future $e^+e^-$ colliders taking into account the full set of Feynman diagrams for six fermion final states. We also include in our calculations initial state radiation and beamstrahlung effects, and the most important QCD corrections in an approximate (naive) form. We compare such a complete approach with "production x decay" approximation and we suggest that in many physical studies the former is needed.
1102.1680
Jusak Tandean
Sechul Oh, Jusak Tandean
Constraints on a New Light Spin-One Particle from Rare b -> s Transitions
19 pages, 5 figures
Phys.Rev.D83:095006,2011
10.1103/PhysRevD.83.095006
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The anomalously large like-sign dimuon charge asymmetry in semileptonic b-hadron decays recently measured by the D0 Collaboration may be hinting at the presence of CP-violating new physics in the mixing of B_s mesons. It has been suggested that the effect of a nonstandard spin-1 particle lighter than the b quark with flavor-changing couplings to b and s quarks can reproduce the D0 result within its one-sigma range. Here we explore the possibility that the new particle also couples to charged leptons l=e,mu and thus contributes to rare b -> s processes involving the leptons. We consider in particular constraints on its couplings from existing experimental data on the inclusive B -> X_s l^+ l^- and exclusive B -> K^{(*)} l^+ l^- decays, as well as the anomalous magnetic moments of the leptons. We find that there is parameter space of the particle that is allowed by the current data. Future measurements of these B transitions and rare decays of the B_s meson, such as B_s -> (phi,eta,eta') l^+ l^- and B_s -> l^+ l^-, at LHCb and next-generation B factories can probe its presence or couplings more stringently.
[ { "created": "Tue, 8 Feb 2011 18:38:54 GMT", "version": "v1" } ]
2015-03-18
[ [ "Oh", "Sechul", "" ], [ "Tandean", "Jusak", "" ] ]
The anomalously large like-sign dimuon charge asymmetry in semileptonic b-hadron decays recently measured by the D0 Collaboration may be hinting at the presence of CP-violating new physics in the mixing of B_s mesons. It has been suggested that the effect of a nonstandard spin-1 particle lighter than the b quark with flavor-changing couplings to b and s quarks can reproduce the D0 result within its one-sigma range. Here we explore the possibility that the new particle also couples to charged leptons l=e,mu and thus contributes to rare b -> s processes involving the leptons. We consider in particular constraints on its couplings from existing experimental data on the inclusive B -> X_s l^+ l^- and exclusive B -> K^{(*)} l^+ l^- decays, as well as the anomalous magnetic moments of the leptons. We find that there is parameter space of the particle that is allowed by the current data. Future measurements of these B transitions and rare decays of the B_s meson, such as B_s -> (phi,eta,eta') l^+ l^- and B_s -> l^+ l^-, at LHCb and next-generation B factories can probe its presence or couplings more stringently.
2004.08399
Pierluca Carenza
Pierluca Carenza (Bari Univ. & INFN Bari), Oscar Straniero (INAF), Babette D\"obrich (CERN), Maurizio Giannotti (Barry Univ.), Giuseppe Lucente (Bari Univ.), Alessandro Mirizzi (Bari Univ. & INFN Bari)
Constraints on the coupling with photons of heavy axion-like-particles from Globular Clusters
10 pages, 5 figures. v2: Revised version. Matches the version published on PLB. Improved the discussion on axion energy transfer in HB stars. Added two Appendices on photon-axion transition rate from Primakoff conversion and on photon coalescence
Physics Letters B, Volume 809, 10 October 2020, 135709
10.1016/j.physletb.2020.135709
null
hep-ph astro-ph.SR hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We update the globular cluster bound on massive ($m_a$ up to a few 100 keV) axion-like particles (ALP) interacting with photons. The production of such particles in the stellar core is dominated by the Primakoff $\gamma + Ze\to Ze +a$ and by the photon coalescence process $\gamma+\gamma\to a$. The latter, which is predominant at high masses, was not included in previous estimations. Furthermore, we account for the possibility that axions decay inside the stellar core, a non-negligible effect at the masses and couplings we are considering here. Consequently, our result modifies considerably the previous constraint, especially for $m_a \gtrsim 50$ keV. The combined constraints from Globular Cluster stars, SN 1987A, and beam-dump experiments leave a small triangularly shaped region open in the parameter space around $m_a \sim 0.5-1\,$ MeV and $g_{a\gamma} \sim 10^{-5}$ GeV$^{-1}$. This is informally known as the ALP "cosmological triangle" since it can be excluded only using standard cosmological arguments. As we shall mention, however, there are viable cosmological models that are compatible with axion-like particles with parameters in such region. We also discuss possibilities to explore the cosmological triangle experimentally in upcoming accelerator experiments.
[ { "created": "Fri, 17 Apr 2020 18:00:06 GMT", "version": "v1" }, { "created": "Thu, 3 Sep 2020 06:13:12 GMT", "version": "v2" } ]
2020-09-04
[ [ "Carenza", "Pierluca", "", "Bari Univ. & INFN Bari" ], [ "Straniero", "Oscar", "", "INAF" ], [ "Döbrich", "Babette", "", "CERN" ], [ "Giannotti", "Maurizio", "", "Barry Univ." ], [ "Lucente", "Giuseppe", "", "Bari Univ." ], [ "Mirizzi", "Alessandro", "", "Bari Univ. & INFN Bari" ] ]
We update the globular cluster bound on massive ($m_a$ up to a few 100 keV) axion-like particles (ALP) interacting with photons. The production of such particles in the stellar core is dominated by the Primakoff $\gamma + Ze\to Ze +a$ and by the photon coalescence process $\gamma+\gamma\to a$. The latter, which is predominant at high masses, was not included in previous estimations. Furthermore, we account for the possibility that axions decay inside the stellar core, a non-negligible effect at the masses and couplings we are considering here. Consequently, our result modifies considerably the previous constraint, especially for $m_a \gtrsim 50$ keV. The combined constraints from Globular Cluster stars, SN 1987A, and beam-dump experiments leave a small triangularly shaped region open in the parameter space around $m_a \sim 0.5-1\,$ MeV and $g_{a\gamma} \sim 10^{-5}$ GeV$^{-1}$. This is informally known as the ALP "cosmological triangle" since it can be excluded only using standard cosmological arguments. As we shall mention, however, there are viable cosmological models that are compatible with axion-like particles with parameters in such region. We also discuss possibilities to explore the cosmological triangle experimentally in upcoming accelerator experiments.
0903.3640
Yukinari Sumino
Y. Sumino
Family Gauge Symmetry as an Origin of Koide's Mass Formula and Charged Lepton Spectrum
17 pages, 12 figures
null
null
TU-842
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently we have proposed mechanisms to explain origins of the charged lepton spectrum as well as Koide's mass formula, on the basis of U(3)\times O(3) family gauge symmetry. In this note, we review the basic ideas of these mechanisms. Without technical details, and adding some speculations, we give a sketch of the mechanisms, what the important points are and what assumptions are involved. We adopt a known scenario, in which the charged lepton spectrum is determined by the vacuum expectation value of a scalar field that takes values on 3-by-3 matrix. Within this scenario, we propose a mechanism, in which the radiative correction induced by U(3) family gauge interaction cancels the QED radiative correction to Koide's mass formula. We consider SU(9)\times U(1) symmetry broken down to U(3)\times O(3) symmetry. This leads to a potential model which predicts Koide's mass formula and the charged lepton spectrum consistent with the experimental values, by largely avoiding fine tuning of parameters. These are discussed within an effective theory, and we argue for its validity and usefulness.
[ { "created": "Sat, 21 Mar 2009 07:44:05 GMT", "version": "v1" } ]
2016-04-26
[ [ "Sumino", "Y.", "" ] ]
Recently we have proposed mechanisms to explain origins of the charged lepton spectrum as well as Koide's mass formula, on the basis of U(3)\times O(3) family gauge symmetry. In this note, we review the basic ideas of these mechanisms. Without technical details, and adding some speculations, we give a sketch of the mechanisms, what the important points are and what assumptions are involved. We adopt a known scenario, in which the charged lepton spectrum is determined by the vacuum expectation value of a scalar field that takes values on 3-by-3 matrix. Within this scenario, we propose a mechanism, in which the radiative correction induced by U(3) family gauge interaction cancels the QED radiative correction to Koide's mass formula. We consider SU(9)\times U(1) symmetry broken down to U(3)\times O(3) symmetry. This leads to a potential model which predicts Koide's mass formula and the charged lepton spectrum consistent with the experimental values, by largely avoiding fine tuning of parameters. These are discussed within an effective theory, and we argue for its validity and usefulness.
hep-ph/9311348
null
S.Balk, A.Ilakovac, J.G.Korner and D.Pirjol
Two Heavy Quark Effective Theories
12 pages, 2 figures (available upon request), LaTeX (no macros required), minor typos corrected MZ-TH/93-33
null
null
null
hep-ph
null
We point out that there exist two different formulations of the Heavy Quark Effective Theory (HQET). One formulation of HQET was mostly developed at Harvard and involves the use of the equation of motion to eliminate the small components of the heavy quark field. The second formulation, developed in Mainz, involves a series of Foldy-Wouthuysen-type field transformations which diagonalizes the heavy quark Lagrangian. Starting at O($1/m_Q^2$) the two formulations are different in that their effective Lagrangians, their effective currents, and their fields differ. However, when these three differences are properly taken into account, the two alternative formulations lead to identical S-matrix elements. This is demonstrated in an explicit example at O($1/m_Q^2$). We point to an essential difficulty of the Harvard HQET in that the Harvard effective fields are not properly normalized starting at order $O(1/m_Q^2)$.
[ { "created": "Tue, 23 Nov 1993 20:21:07 GMT", "version": "v1" }, { "created": "Thu, 2 Dec 1993 16:34:51 GMT", "version": "v2" } ]
2009-09-25
[ [ "Balk", "S.", "" ], [ "Ilakovac", "A.", "" ], [ "Korner", "J. G.", "" ], [ "Pirjol", "D.", "" ] ]
We point out that there exist two different formulations of the Heavy Quark Effective Theory (HQET). One formulation of HQET was mostly developed at Harvard and involves the use of the equation of motion to eliminate the small components of the heavy quark field. The second formulation, developed in Mainz, involves a series of Foldy-Wouthuysen-type field transformations which diagonalizes the heavy quark Lagrangian. Starting at O($1/m_Q^2$) the two formulations are different in that their effective Lagrangians, their effective currents, and their fields differ. However, when these three differences are properly taken into account, the two alternative formulations lead to identical S-matrix elements. This is demonstrated in an explicit example at O($1/m_Q^2$). We point to an essential difficulty of the Harvard HQET in that the Harvard effective fields are not properly normalized starting at order $O(1/m_Q^2)$.
1310.3887
Stefan Meinel
Ronald R. Horgan, Zhaofeng Liu, Stefan Meinel, Matthew Wingate
Calculation of $B^0 \to K^{*0} \mu^+ \mu^-$ and $B_s^0 \to \phi \mu^+ \mu^-$ observables using form factors from lattice QCD
6 pages. Updated form factors according to arXiv:1310.3722v3. New discussion of charmonium resonances. Accepted by PRL
Phys. Rev. Lett. 112, 212003 (2014)
10.1103/PhysRevLett.112.212003
DAMTP-2013-55, MIT-CTP 4508
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the differential branching fractions and angular distributions of the rare decays $B^0 \to K^{*0} \mu^+ \mu^-$ and $B_s^0 \to \phi \mu^+ \mu^-$, using for the first time form factors from unquenched lattice QCD. We focus on the kinematic region where the $K^*$ or $\phi$ recoils softly; there the newly available form factors are most precise and the nonlocal matrix elements can be included via an operator product expansion. Our results for the differential branching fractions calculated in the Standard Model are higher than the experimental data. We consider the possibility that the deviations are caused by new physics, and perform a fit of the Wilson coefficients $C_9$ and $C_9^\prime$ to the experimental data for multiple $B^0 \to K^{*0} \mu^+ \mu^-$ and $B_s^0 \to \phi \mu^+ \mu^-$ observables. In agreement with recent results from complementary studies, we obtain $C_9-C_9^{SM} = -1.0 \pm 0.6$ and $C_9^\prime = 1.2 \pm 1.0$, whose deviations from zero would indicate the presence of non-standard fundamental interactions.
[ { "created": "Tue, 15 Oct 2013 00:33:52 GMT", "version": "v1" }, { "created": "Fri, 25 Oct 2013 19:33:15 GMT", "version": "v2" }, { "created": "Wed, 7 May 2014 15:08:39 GMT", "version": "v3" } ]
2014-06-02
[ [ "Horgan", "Ronald R.", "" ], [ "Liu", "Zhaofeng", "" ], [ "Meinel", "Stefan", "" ], [ "Wingate", "Matthew", "" ] ]
We calculate the differential branching fractions and angular distributions of the rare decays $B^0 \to K^{*0} \mu^+ \mu^-$ and $B_s^0 \to \phi \mu^+ \mu^-$, using for the first time form factors from unquenched lattice QCD. We focus on the kinematic region where the $K^*$ or $\phi$ recoils softly; there the newly available form factors are most precise and the nonlocal matrix elements can be included via an operator product expansion. Our results for the differential branching fractions calculated in the Standard Model are higher than the experimental data. We consider the possibility that the deviations are caused by new physics, and perform a fit of the Wilson coefficients $C_9$ and $C_9^\prime$ to the experimental data for multiple $B^0 \to K^{*0} \mu^+ \mu^-$ and $B_s^0 \to \phi \mu^+ \mu^-$ observables. In agreement with recent results from complementary studies, we obtain $C_9-C_9^{SM} = -1.0 \pm 0.6$ and $C_9^\prime = 1.2 \pm 1.0$, whose deviations from zero would indicate the presence of non-standard fundamental interactions.
hep-ph/0010273
Thomas Teubner
A. Hebecker and T. Teubner
Skewed Parton Distributions and F_2^D at beta -> 1
11 pages, LaTeX, including five PostScript figures
Phys.Lett.B498:16-22,2001
10.1016/S0370-2693(00)01372-1
CERN-TH/2000-306, PITHA 00/26
hep-ph
null
We show that the diffractive structure function is perturbatively calculable in the domain where the diffractive mass is small but still outside the resonance region. In this domain, which can be characterized by Lambda^2/Q^2 << 1-beta << (Lambda^2/Q^2)^1/2, the structure function represents a new observable, which is highly sensitive to the small-x skewed gluon distribution. Our leading order calculation and the estimate of next-to-leading order corrections are consistent with available data and demonstrate the potential of more precise data to put further constraints on skewing effects.
[ { "created": "Tue, 24 Oct 2000 13:29:16 GMT", "version": "v1" } ]
2009-02-20
[ [ "Hebecker", "A.", "" ], [ "Teubner", "T.", "" ] ]
We show that the diffractive structure function is perturbatively calculable in the domain where the diffractive mass is small but still outside the resonance region. In this domain, which can be characterized by Lambda^2/Q^2 << 1-beta << (Lambda^2/Q^2)^1/2, the structure function represents a new observable, which is highly sensitive to the small-x skewed gluon distribution. Our leading order calculation and the estimate of next-to-leading order corrections are consistent with available data and demonstrate the potential of more precise data to put further constraints on skewing effects.
1705.05789
Kai Ma
Kai Ma
Constrains of Charge-to-Mass Ratios on Noncommutative Phase Space
6pages; v2: text are improved and several references are added. v3: match to the published version
Adv.High Energy Phys. 2017 (2017) 1945156
10.1155/2017/1945156
null
hep-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Based on recent measurements on the charge-to-mass ratios of proton and anti-proton, we study constraints on the parameters of noncommutative phase space. We find that while the limit on the parameter of coordinate noncommutativity is weak, it is very strong on the parameter of momentum noncommutativity, $\sqrt{\xi} \lesssim {\rm 1\mu eV}$. Therefore, the charge-to-mass ratio experiment has a strong sensitivity on the momentum noncommutativity, and enhancement of future experimental achievement can further pin down the momentum noncommutativity.
[ { "created": "Tue, 16 May 2017 16:19:23 GMT", "version": "v1" }, { "created": "Sat, 27 May 2017 02:38:01 GMT", "version": "v2" }, { "created": "Sun, 18 Feb 2018 10:34:06 GMT", "version": "v3" } ]
2018-02-20
[ [ "Ma", "Kai", "" ] ]
Based on recent measurements on the charge-to-mass ratios of proton and anti-proton, we study constraints on the parameters of noncommutative phase space. We find that while the limit on the parameter of coordinate noncommutativity is weak, it is very strong on the parameter of momentum noncommutativity, $\sqrt{\xi} \lesssim {\rm 1\mu eV}$. Therefore, the charge-to-mass ratio experiment has a strong sensitivity on the momentum noncommutativity, and enhancement of future experimental achievement can further pin down the momentum noncommutativity.
0809.1329
Alexander V. Kuznetsov
A.V. Kuznetsov and N.V. Mikheev (Yaroslavl State (P.G. Demidov) University, Russia)
Plasma induced fermion spin-flip conversion $f_L \to f_R + \gamma$
5 pages, LaTeX, 1 PS figure, based on the talk presented by A.V. Kuznetsov at the XV International Seminar Quarks'2008, Sergiev Posad, Moscow Region, May 23-29, 2008, to appear in the Proceedings
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The fermion spin-flip conversion $f_L \to f_R + \gamma$ is considered, caused by the difference of the additional energies of the electroweak origin, acquired by left- and right-handed fermions (neutrino, electron) in medium. An accurate taking account of the fermion and photon dispersion in medium is shown to be important.
[ { "created": "Mon, 8 Sep 2008 13:04:40 GMT", "version": "v1" } ]
2008-09-09
[ [ "Kuznetsov", "A. V.", "", "Yaroslavl State" ], [ "Mikheev", "N. V.", "", "Yaroslavl State" ] ]
The fermion spin-flip conversion $f_L \to f_R + \gamma$ is considered, caused by the difference of the additional energies of the electroweak origin, acquired by left- and right-handed fermions (neutrino, electron) in medium. An accurate taking account of the fermion and photon dispersion in medium is shown to be important.
hep-ph/0201027
Saleev
V.A. Saleev
Photoproduction of J/psi mesons at high energies in parton model and k_t-faktorization approach
LaTeX2e, 11 pages plus 8 fig. using epsfig.sty
Phys.Rev.D65:054041,2002
10.1103/PhysRevD.65.054041
SSU-HEP-01/2002
hep-ph
null
We consider J/psi meson photoproduction on protons at high energies at the leading order in alpha_s using conventional parton model and k_t-factorization approach of QCD. It is shown that in the both cases the colour singlet mechanism gives correct description for experimental data from HERA for the total cross section and for the J/psi meson z-spectrum at realistic values of a c-quark mass and meson wave function at the origin Psi (0). At the same time our predictions for p_t-spectrum of J/psi meson and for p_t dependence of the spin parameter alpha obtained in k_t-factorization approach are very different from the results obtained in conventional parton model. Such a way the experimental study of a polarized J/psi meson production at the large p_t should be a direct test of BFKL gluons.
[ { "created": "Sat, 5 Jan 2002 13:44:31 GMT", "version": "v1" }, { "created": "Mon, 14 Jan 2002 13:44:17 GMT", "version": "v2" } ]
2011-03-23
[ [ "Saleev", "V. A.", "" ] ]
We consider J/psi meson photoproduction on protons at high energies at the leading order in alpha_s using conventional parton model and k_t-factorization approach of QCD. It is shown that in the both cases the colour singlet mechanism gives correct description for experimental data from HERA for the total cross section and for the J/psi meson z-spectrum at realistic values of a c-quark mass and meson wave function at the origin Psi (0). At the same time our predictions for p_t-spectrum of J/psi meson and for p_t dependence of the spin parameter alpha obtained in k_t-factorization approach are very different from the results obtained in conventional parton model. Such a way the experimental study of a polarized J/psi meson production at the large p_t should be a direct test of BFKL gluons.
1608.00472
Sergiy Akkelin
S.V. Akkelin
Hot origin of the Little Bang
17 pages
Eur. Phys. J. A (2017) 53: 232
10.1140/epja/i2017-12432-1
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Ultrarelativistic heavy ion collisions produce a quark-gluon matter which lies in the future light cone originating from given points on the $t=z=0$ plane of the Minkowski spacetime manifold. We show that in a weak coupling regime the Minkowski vacuum of massless fields presents itself in the "Little Bang" region as a thermal state of low $p_{T}$ particles, in close analogy to the Unruh effect for uniformly accelerated observers which are causally restricted to a Rindler wedge. It can shed some light on the mechanisms of early time thermalization in ultrarelativistic heavy ion collisions.
[ { "created": "Mon, 1 Aug 2016 15:32:24 GMT", "version": "v1" }, { "created": "Tue, 6 Sep 2016 13:33:50 GMT", "version": "v2" }, { "created": "Thu, 27 Oct 2016 16:05:11 GMT", "version": "v3" }, { "created": "Fri, 14 Jul 2017 10:20:42 GMT", "version": "v4" }, { "created": "Fri, 1 Dec 2017 14:05:36 GMT", "version": "v5" } ]
2017-12-04
[ [ "Akkelin", "S. V.", "" ] ]
Ultrarelativistic heavy ion collisions produce a quark-gluon matter which lies in the future light cone originating from given points on the $t=z=0$ plane of the Minkowski spacetime manifold. We show that in a weak coupling regime the Minkowski vacuum of massless fields presents itself in the "Little Bang" region as a thermal state of low $p_{T}$ particles, in close analogy to the Unruh effect for uniformly accelerated observers which are causally restricted to a Rindler wedge. It can shed some light on the mechanisms of early time thermalization in ultrarelativistic heavy ion collisions.
hep-ph/0202273
Ilicheva Tatiana
T.P.Ilichova, S.G Shulga
Nucleon electromagnetic form factors in a single-time constituent quark model
6 pages, 1 figures, VIth International School-Seminar ``Actual Problems of Particle Physics'', July 30 - August 8, 1999, Gomel, Belarus
null
null
null
hep-ph
null
The main statement of the nucleon constituent quark model with a fixed number of particles as basic ansatz are considered in a framework of the single-time (quasipotential) approach to the bound state problem. The scaling law breacking for the proton form factor is investigated for Q^2 = 0 -- 2 Gev^2.
[ { "created": "Thu, 28 Feb 2002 08:59:02 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ilichova", "T. P.", "" ], [ "Shulga", "S. G", "" ] ]
The main statement of the nucleon constituent quark model with a fixed number of particles as basic ansatz are considered in a framework of the single-time (quasipotential) approach to the bound state problem. The scaling law breacking for the proton form factor is investigated for Q^2 = 0 -- 2 Gev^2.
0909.1547
Johannes Bluemlein
J. Bl\"umlein, S. Klein, and B. T\"odtli
$O(\alpha_s^2)$ and $O(\alpha_s^3)$ Heavy Flavor Contributions to Transversity at $Q^2 \gg m^2$
25 papes, 5 figures, 1 style file
Phys.Rev.D80:094010,2009
10.1103/PhysRevD.80.094010
DESY 09-60, SFB/CPP-09-073
hep-ph hep-ex hep-lat hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In deep-inelastic processes the heavy flavor Wilson coefficients factorize for $Q^2 \gg m^2$ into the light flavor Wilson coefficients of the corresponding process and the massive operator matrix elements (OMEs). We calculate the $O(\alpha_s^2)$ and $O(\alpha_s^3)$ massive OME for the flavor non-singlet transversity distribution. At $O(\alpha_s^2)$ the OME is obtained for general values of the Mellin variable $N$, while at $O(\alpha_s^3)$ the moments $N = 1$ to 13 are computed. The terms $\propto T_F$ of the 3--loop transversity anomalous dimension are obtained and results in the literature are confirmed. We discuss the relation of these contributions to the Soffer bound for transversity.
[ { "created": "Tue, 8 Sep 2009 19:47:21 GMT", "version": "v1" } ]
2009-11-30
[ [ "Blümlein", "J.", "" ], [ "Klein", "S.", "" ], [ "Tödtli", "B.", "" ] ]
In deep-inelastic processes the heavy flavor Wilson coefficients factorize for $Q^2 \gg m^2$ into the light flavor Wilson coefficients of the corresponding process and the massive operator matrix elements (OMEs). We calculate the $O(\alpha_s^2)$ and $O(\alpha_s^3)$ massive OME for the flavor non-singlet transversity distribution. At $O(\alpha_s^2)$ the OME is obtained for general values of the Mellin variable $N$, while at $O(\alpha_s^3)$ the moments $N = 1$ to 13 are computed. The terms $\propto T_F$ of the 3--loop transversity anomalous dimension are obtained and results in the literature are confirmed. We discuss the relation of these contributions to the Soffer bound for transversity.
hep-ph/0211345
Erler
Jens Erler
Electroweak Radiative Corrections to Semileptonic Tau Decays
3 pages
Rev.Mex.Fis. 50 (2004) 200-202
null
null
hep-ph hep-ex
null
I present an update on the electroweak radiative correction factor to semileptonic tau decays, including a next-to-leading order resummation of large logarithms. My result differs both qualitatively and quantitatively from the one recently obtained by Davier et al. As two consequences, (i) the discrepancy between the predictions for the muon g-2 based on tau decay data and electron-positron annihilation data increases, and (ii) the g-2 prediction based on tau decay data appears to be consistent (within about one standard deviation) with the experimental result from BNL.
[ { "created": "Fri, 22 Nov 2002 02:35:56 GMT", "version": "v1" }, { "created": "Mon, 25 Nov 2002 00:05:55 GMT", "version": "v2" } ]
2007-05-23
[ [ "Erler", "Jens", "" ] ]
I present an update on the electroweak radiative correction factor to semileptonic tau decays, including a next-to-leading order resummation of large logarithms. My result differs both qualitatively and quantitatively from the one recently obtained by Davier et al. As two consequences, (i) the discrepancy between the predictions for the muon g-2 based on tau decay data and electron-positron annihilation data increases, and (ii) the g-2 prediction based on tau decay data appears to be consistent (within about one standard deviation) with the experimental result from BNL.
1110.5909
Erich Weihs
Erich Weihs and Jose Zurita
Dark Higgs Models at the 7 TeV LHC
20 pages, 8 figures; references, clarification and note added; conclusions unaltered; version accepted for publication in JHEP; v3: added references
JHEP 1202 (2012) 041
10.1007/JHEP02(2012)041
ZU-TH 20/11; LPN11-56
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study how collider data and electroweak precision observables affect the parameter space of models including a new dark force mediated by a massive U(1) gauge boson. It acquires mass via a Higgs mechanism in the dark sector which is connected to the Standard Model through kinetic mixing of the two U(1) gauge bosons and the Higgs potential. We assess the impact of the 7 TeV LHC and show that most of the parameter space of the model can be probed with an integrated luminosity of 15 fb^-1.
[ { "created": "Wed, 26 Oct 2011 20:00:02 GMT", "version": "v1" }, { "created": "Fri, 16 Mar 2012 12:31:26 GMT", "version": "v2" }, { "created": "Mon, 7 May 2012 10:48:17 GMT", "version": "v3" } ]
2012-05-08
[ [ "Weihs", "Erich", "" ], [ "Zurita", "Jose", "" ] ]
We study how collider data and electroweak precision observables affect the parameter space of models including a new dark force mediated by a massive U(1) gauge boson. It acquires mass via a Higgs mechanism in the dark sector which is connected to the Standard Model through kinetic mixing of the two U(1) gauge bosons and the Higgs potential. We assess the impact of the 7 TeV LHC and show that most of the parameter space of the model can be probed with an integrated luminosity of 15 fb^-1.
0706.2738
Johannes Bluemlein
I. Bierenbaum, J. Bl\"umlein and S. Klein
Two-Loop Massive Operator Matrix Elements for Polarized and Unpolarized Deep-Inelastic Scattering
1 latex file, 1 style file, Proceedings DIS 2007, Munich, April 2007
null
null
DESY 07/089, SFB/CPP-07-30
hep-ph
null
The $O(\alpha_s^2)$ massive operator matrix elements for unpolarized and polarized heavy flavor production at asymptotic values $Q^2 >> m^2$ are calculated in Mellin space without applying the integration-by-parts method. We confirm previous results given in Refs. \cite{BU1,BU2}, however, obtain much more compact representations.
[ { "created": "Tue, 19 Jun 2007 08:59:23 GMT", "version": "v1" } ]
2007-06-20
[ [ "Bierenbaum", "I.", "" ], [ "Blümlein", "J.", "" ], [ "Klein", "S.", "" ] ]
The $O(\alpha_s^2)$ massive operator matrix elements for unpolarized and polarized heavy flavor production at asymptotic values $Q^2 >> m^2$ are calculated in Mellin space without applying the integration-by-parts method. We confirm previous results given in Refs. \cite{BU1,BU2}, however, obtain much more compact representations.
2402.19086
Konstantinos Dimopoulos
Konstantinos Dimopoulos
Cosmic Inflation, Dark Energy and Gravitational Waves
10 pages, contribution to the 21st Lomonosov conference, August 24-30, 2023
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We briefly discuss cosmic inflation, which is the dominant paradigm for the generation of the large scale structure in the Universe and also for arranging for the initial conditions of the hot Big Bang. We then present quintessential inflation, which also accounts of the observed dark energy. We discuss how quintessential inflation can be successfully modelled in modified gravity in the Palatini formalism. Finally, we focus on the generation of primordial gravitational waves by inflation and how their spectrum can be enhanced when the early Universe goes through periods of stiff equation of state. This results in gravitational waves with a characteristic spectrum, which may well be observed in the near future, providing insights for the background theory.
[ { "created": "Thu, 29 Feb 2024 12:12:38 GMT", "version": "v1" } ]
2024-03-01
[ [ "Dimopoulos", "Konstantinos", "" ] ]
We briefly discuss cosmic inflation, which is the dominant paradigm for the generation of the large scale structure in the Universe and also for arranging for the initial conditions of the hot Big Bang. We then present quintessential inflation, which also accounts of the observed dark energy. We discuss how quintessential inflation can be successfully modelled in modified gravity in the Palatini formalism. Finally, we focus on the generation of primordial gravitational waves by inflation and how their spectrum can be enhanced when the early Universe goes through periods of stiff equation of state. This results in gravitational waves with a characteristic spectrum, which may well be observed in the near future, providing insights for the background theory.
hep-ph/9505277
Oleg Tarasov
O. V. TARASOV
AN ALGORITHM FOR SMALL MOMENTUM EXPANSION OF FEYNMAN DIAGRAMS
7 page, Talk presented at the AI-HENP 95 workshop, Pisa, April 1995 (Some minor misprints are corrected)
null
null
BI-TP-95/19
hep-ph
null
An algorithm for obtaining the Taylor coefficients of an expansion of Feynman diagrams is proposed. It is based on recurrence relations which can be applied to the propagator as well as to the vertex diagrams. As an application, several coefficients of the Taylor series expansion for the two-loop propagator and two-loop non-planar vertex diagrams are calculated. The results of the numerical evaluation of these diagrams using conformal mapping and Pade approximants are given.
[ { "created": "Thu, 11 May 1995 03:04:02 GMT", "version": "v1" }, { "created": "Thu, 11 May 1995 21:39:32 GMT", "version": "v2" } ]
2008-02-03
[ [ "TARASOV", "O. V.", "" ] ]
An algorithm for obtaining the Taylor coefficients of an expansion of Feynman diagrams is proposed. It is based on recurrence relations which can be applied to the propagator as well as to the vertex diagrams. As an application, several coefficients of the Taylor series expansion for the two-loop propagator and two-loop non-planar vertex diagrams are calculated. The results of the numerical evaluation of these diagrams using conformal mapping and Pade approximants are given.
hep-ph/0010351
Arash Mafi
Arash Mafi
$\mu$ Problem, SO(10) SUSY GUT and Heavy Gluino LSP
Talk given at The Meeting of The Division of Particles and Fields of The American Physical Society (DPF 2000), Columbus, Ohio, August 9-12, 2000, 3 pp
Int.J.Mod.Phys. A16S1B (2001) 849-851
10.1142/S0217751X0100828X
OHSTPY-HEP-T-00-024
hep-ph
null
We present a solution to the $\mu$ problem in an SO(10) supersymmetric grand unified (SUSY GUT) model with gauge mediated (GMSB) and D-term supersymmetry breaking. A Peccei-Quinn ({\bf PQ}) symmetry is broken at the messenger scale and enables the generation of the $\mu$ term. The invisible axion (Goldstone boson of {\bf PQ} symmetry breaking) is a cold dark matter candidate. At low energy, our model leads to a phenomenologically acceptable version of the minimal supersymmetric standard model (MSSM) with novel particle phenomenology. Either the gluino or the gravitino is the lightest supersymmetric particle (LSP). The phenomenological constraints on the model result in a Higgs with mass $\sim 86 - 91$ GeV and $\tan\beta \sim 9 - 14$.
[ { "created": "Tue, 31 Oct 2000 18:45:00 GMT", "version": "v1" } ]
2009-10-31
[ [ "Mafi", "Arash", "" ] ]
We present a solution to the $\mu$ problem in an SO(10) supersymmetric grand unified (SUSY GUT) model with gauge mediated (GMSB) and D-term supersymmetry breaking. A Peccei-Quinn ({\bf PQ}) symmetry is broken at the messenger scale and enables the generation of the $\mu$ term. The invisible axion (Goldstone boson of {\bf PQ} symmetry breaking) is a cold dark matter candidate. At low energy, our model leads to a phenomenologically acceptable version of the minimal supersymmetric standard model (MSSM) with novel particle phenomenology. Either the gluino or the gravitino is the lightest supersymmetric particle (LSP). The phenomenological constraints on the model result in a Higgs with mass $\sim 86 - 91$ GeV and $\tan\beta \sim 9 - 14$.
1708.04549
Soumitra Maity
Abhijit Bhattacharyya, Sanjay K. Ghosh, Soumitra Maity, Sibaji Raha, Rajarshi Ray, Kinkar Saha, Subhasis Samanta and Sudipa Upadhaya
Thermodynamics of strongly interacting matter in a hybrid model
17 pages, 10 figures. arXiv admin note: text overlap with arXiv:1609.07882
Phys. Rev. C 99, 045207 (2019)
10.1103/PhysRevC.99.045207
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The equation of state and fluctuations of conserved charges in a strongly interacting medium under equilibrium conditions form the baseline upon which various possible scenarios in relativistic heavy-ion collision experiments are built. Many of these quantities have been obtained in the lattice QCD framework with reliable continuum extrapolations. Recently the Polyakov$-$Nambu$-$Jona-Lasinio model has been reparametrized to some extent to reproduce quantitatively the lattice QCD equation of state at vanishing chemical potentials. The agreement was precise except at low temperatures, possibly due to inadequate representation of the hadronic degrees of freedom in the model. This disagreement was also observed for some of the fluctuation and correlations considered. Here we address this issue by introducing the effects of hadrons through the Hadron Resonance Gas model. The total thermodynamic potential is now a weighted sum of the thermodynamic potential of the Polyakov$-$Nambu$-$Jona-Lasinio model and that of the Hadron Resonance Gas model. We find that the equation of state and the fluctuations and correlations obtained in this hybrid model agrees satisfactorily with the lattice QCD data in the low temperature regime.
[ { "created": "Mon, 14 Aug 2017 12:39:00 GMT", "version": "v1" } ]
2019-05-01
[ [ "Bhattacharyya", "Abhijit", "" ], [ "Ghosh", "Sanjay K.", "" ], [ "Maity", "Soumitra", "" ], [ "Raha", "Sibaji", "" ], [ "Ray", "Rajarshi", "" ], [ "Saha", "Kinkar", "" ], [ "Samanta", "Subhasis", "" ], [ "Upadhaya", "Sudipa", "" ] ]
The equation of state and fluctuations of conserved charges in a strongly interacting medium under equilibrium conditions form the baseline upon which various possible scenarios in relativistic heavy-ion collision experiments are built. Many of these quantities have been obtained in the lattice QCD framework with reliable continuum extrapolations. Recently the Polyakov$-$Nambu$-$Jona-Lasinio model has been reparametrized to some extent to reproduce quantitatively the lattice QCD equation of state at vanishing chemical potentials. The agreement was precise except at low temperatures, possibly due to inadequate representation of the hadronic degrees of freedom in the model. This disagreement was also observed for some of the fluctuation and correlations considered. Here we address this issue by introducing the effects of hadrons through the Hadron Resonance Gas model. The total thermodynamic potential is now a weighted sum of the thermodynamic potential of the Polyakov$-$Nambu$-$Jona-Lasinio model and that of the Hadron Resonance Gas model. We find that the equation of state and the fluctuations and correlations obtained in this hybrid model agrees satisfactorily with the lattice QCD data in the low temperature regime.
1409.5885
Wally Melnitchouk
Yusupujiang Salamu, Chueng-Ryong Ji, W. Melnitchouk, P. Wang
$\bar d - \bar u$ asymmetry in the proton in chiral effective theory
5 pages, 3 figures; minor typos corrected; version published in PRL
Phys. Rev. Lett. 114, 122001 (2015)
10.1103/PhysRevLett.114.122001
JLAB-THY-14-1954
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the $\bar d - \bar u$ asymmetry in the proton in chiral effective theory, including both nucleon and $\Delta$ degrees of freedom, within both the relativistic and heavy baryon frameworks. In addition to the distribution at $x>0$, we compute the corrections to the asymmetry arising from zero momentum contributions from pion rainbow and bubble diagrams at $x=0$, which have not been accounted for in previous analyses. We find that the empirical $x$ dependence of $\bar d - \bar u$ as well as the integrated asymmetry can be well reproduced in terms of a transverse momentum cutoff parameter.
[ { "created": "Sat, 20 Sep 2014 13:20:53 GMT", "version": "v1" }, { "created": "Tue, 14 Jul 2015 19:48:04 GMT", "version": "v2" } ]
2015-10-02
[ [ "Salamu", "Yusupujiang", "" ], [ "Ji", "Chueng-Ryong", "" ], [ "Melnitchouk", "W.", "" ], [ "Wang", "P.", "" ] ]
We compute the $\bar d - \bar u$ asymmetry in the proton in chiral effective theory, including both nucleon and $\Delta$ degrees of freedom, within both the relativistic and heavy baryon frameworks. In addition to the distribution at $x>0$, we compute the corrections to the asymmetry arising from zero momentum contributions from pion rainbow and bubble diagrams at $x=0$, which have not been accounted for in previous analyses. We find that the empirical $x$ dependence of $\bar d - \bar u$ as well as the integrated asymmetry can be well reproduced in terms of a transverse momentum cutoff parameter.
1801.06067
Pablo Sanchez Puertas
Karol Kampf, Jiri Novotny, Pablo Sanchez-Puertas
The radiative corrections to double-Dalitz decays revisited
22 pages, 9 figures; minor changes added (results unchanged). Matches the published version in PRD. Results in Mathematica notebooks added as ancillary files
Phys. Rev. D 97, 056010 (2018)
10.1103/PhysRevD.97.056010
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this study, we revisit and complete the full next-to-leading order corrections to pseudoscalar double-Dalitz decays within the soft-photon approximation. Comparing to the previous study, we find small differences, which are nevertheless relevant for extracting information about the pseudoscalar transition form factors. Concerning the latter, these processes could offer the opportunity to test them-for the first time-in their double-virtual regime
[ { "created": "Thu, 18 Jan 2018 14:51:09 GMT", "version": "v1" }, { "created": "Mon, 19 Mar 2018 12:55:41 GMT", "version": "v2" }, { "created": "Thu, 28 Mar 2019 17:34:57 GMT", "version": "v3" } ]
2019-03-29
[ [ "Kampf", "Karol", "" ], [ "Novotny", "Jiri", "" ], [ "Sanchez-Puertas", "Pablo", "" ] ]
In this study, we revisit and complete the full next-to-leading order corrections to pseudoscalar double-Dalitz decays within the soft-photon approximation. Comparing to the previous study, we find small differences, which are nevertheless relevant for extracting information about the pseudoscalar transition form factors. Concerning the latter, these processes could offer the opportunity to test them-for the first time-in their double-virtual regime
1706.02253
Evan Johnson
Eric Braaten, Evan Johnson, Hong Zhang
Zero-Range Effective Field Theory for Resonant Wino Dark Matter I. Framework
63 pages, 22 figures, Corrected typos in version 1
null
10.1007/JHEP11(2017)108
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The most dramatic "Sommerfeld enhancements" of neutral-wino-pair annihilation occur when the wino mass is near a critical value where there is a zero-energy S-wave resonance at the neutral-wino-pair threshold. Near such a critical mass, low-energy winos can be described by a zero-range effective field theory in which the winos interact nonperturbatively through a contact interaction. The effective field theory is controlled by a renormalization-group fixed point at which the neutral and charged winos are degenerate in mass and their scattering length is infinite. The parameters of the zero-range effective field theory can be determined by matching wino-wino scattering amplitudes calculated by solving the Schr\"odinger equation for winos interacting through a potential due to the exchange of weak gauge bosons. If the wino mass is larger than the critical value, the resonance is a wino-pair bound state. The power of the zero-range effective field theory is illustrated by calculating the rate for formation of the bound state in the collision of two neutral winos through the emission of two soft photons.
[ { "created": "Wed, 7 Jun 2017 16:51:10 GMT", "version": "v1" }, { "created": "Wed, 15 Nov 2017 20:48:36 GMT", "version": "v2" } ]
2017-12-06
[ [ "Braaten", "Eric", "" ], [ "Johnson", "Evan", "" ], [ "Zhang", "Hong", "" ] ]
The most dramatic "Sommerfeld enhancements" of neutral-wino-pair annihilation occur when the wino mass is near a critical value where there is a zero-energy S-wave resonance at the neutral-wino-pair threshold. Near such a critical mass, low-energy winos can be described by a zero-range effective field theory in which the winos interact nonperturbatively through a contact interaction. The effective field theory is controlled by a renormalization-group fixed point at which the neutral and charged winos are degenerate in mass and their scattering length is infinite. The parameters of the zero-range effective field theory can be determined by matching wino-wino scattering amplitudes calculated by solving the Schr\"odinger equation for winos interacting through a potential due to the exchange of weak gauge bosons. If the wino mass is larger than the critical value, the resonance is a wino-pair bound state. The power of the zero-range effective field theory is illustrated by calculating the rate for formation of the bound state in the collision of two neutral winos through the emission of two soft photons.