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1007.4206
Jose Santiago
Francisco del Aguila, Adrian Carmona, Jose Santiago
Tau Custodian searches at the LHC
12 pages, 2 figures
Phys.Lett.B695:449-453,2011
10.1016/j.physletb.2010.11.054
CAFPE-143/10,UGFT-273/10
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The tau lepton can be more composite than naively expected in models of strong electroweak symmetry breaking with tri-bimaximal lepton mixing. New leptonic resonances required by custodial symmetry, the tau custodians, can then be the first signal of this lepton flavor realization. Tau custodians can be very light, decaying almost exclusively into taus. The LHC reach for these new leptons is up to masses of 240, 480 and 720 GeV for sqrt{s}=14 TeV and an integrated luminosity of 30, 300 and 3000 fb^{-1}, respectively. Our analysis can be extended to any pair produced particles decaying mostly into taus and Standard Model bosons.
[ { "created": "Fri, 23 Jul 2010 20:09:57 GMT", "version": "v1" } ]
2011-01-04
[ [ "del Aguila", "Francisco", "" ], [ "Carmona", "Adrian", "" ], [ "Santiago", "Jose", "" ] ]
The tau lepton can be more composite than naively expected in models of strong electroweak symmetry breaking with tri-bimaximal lepton mixing. New leptonic resonances required by custodial symmetry, the tau custodians, can then be the first signal of this lepton flavor realization. Tau custodians can be very light, decaying almost exclusively into taus. The LHC reach for these new leptons is up to masses of 240, 480 and 720 GeV for sqrt{s}=14 TeV and an integrated luminosity of 30, 300 and 3000 fb^{-1}, respectively. Our analysis can be extended to any pair produced particles decaying mostly into taus and Standard Model bosons.
hep-ph/9711470
Piotr Chankowski
P.H. Chankowski (Inst. of Theor. Physics, Warsaw Univ.)
Constraints on low energy supersymmetry
16 pages, 8 figures. Talk given at the International Workshop on Quantum Effects in the MSSM, Barcelona, September 1997, to apper in the Proceedings
null
null
IFT-97/18
hep-ph
null
We review the available constraints on the low energy supersymmetry. The bulk of the electroweak data is well screened from supersymmetric loop effects, due to the structure of the theory, even with superpartners generically light, ${\cal O}(M_Z)$. The only exception are the left-handed squarks of the third generation which have to be $\simgt {\cal O}(300$ GeV) to maintain the success of the SM in describing the precision data. The other superpartners can still be light, at their present experimental mass limits. As an application of the derived constraints (supplemented by the requirement of ``naturalness'') we discuss the predictions for the mass of the lighter MSSM Higgs boson in specific scanarios of supersymmetry breaking.
[ { "created": "Tue, 25 Nov 1997 15:19:24 GMT", "version": "v1" } ]
2007-05-23
[ [ "Chankowski", "P. H.", "", "Inst. of Theor. Physics, Warsaw Univ." ] ]
We review the available constraints on the low energy supersymmetry. The bulk of the electroweak data is well screened from supersymmetric loop effects, due to the structure of the theory, even with superpartners generically light, ${\cal O}(M_Z)$. The only exception are the left-handed squarks of the third generation which have to be $\simgt {\cal O}(300$ GeV) to maintain the success of the SM in describing the precision data. The other superpartners can still be light, at their present experimental mass limits. As an application of the derived constraints (supplemented by the requirement of ``naturalness'') we discuss the predictions for the mass of the lighter MSSM Higgs boson in specific scanarios of supersymmetry breaking.
hep-ph/9602208
Paolo Nason
S. Catani, M.L. Mangano, P. Nason and L. Trentadue
The Top Cross Section in Hadronic Collisions
17 pages, Latex, epsfig, 7 figures. Revised version. Updated experimental results. Minor changes in the cross section tables. To appear on Phys. Lett. B
Phys.Lett. B378 (1996) 329-336
10.1016/0370-2693(96)00387-5
CERN-TH/96-21
hep-ph
null
We reexamine the top quark production cross section at the Tevatron and LHC, in the light of recent progress on the resummation of logarithmic soft gluon corrections. We find that resummation effects are much smaller than previously thought. We also compute Coulombic threshold effects, and find them negligible. We update the discussion of uncertainties due to scale dependence, the value of the strong coupling constant, and the parton density parametrization. Our current best estimate of the top production cross section at the Tevatron and its error is $\sigma(\mt=175\,{\rm GeV})=4.75{+0.73\atop-0.62}$.
[ { "created": "Thu, 1 Feb 1996 17:41:02 GMT", "version": "v1" }, { "created": "Mon, 25 Mar 1996 15:37:07 GMT", "version": "v2" } ]
2009-10-28
[ [ "Catani", "S.", "" ], [ "Mangano", "M. L.", "" ], [ "Nason", "P.", "" ], [ "Trentadue", "L.", "" ] ]
We reexamine the top quark production cross section at the Tevatron and LHC, in the light of recent progress on the resummation of logarithmic soft gluon corrections. We find that resummation effects are much smaller than previously thought. We also compute Coulombic threshold effects, and find them negligible. We update the discussion of uncertainties due to scale dependence, the value of the strong coupling constant, and the parton density parametrization. Our current best estimate of the top production cross section at the Tevatron and its error is $\sigma(\mt=175\,{\rm GeV})=4.75{+0.73\atop-0.62}$.
1606.07808
Marek Lewicki
Olga Czerwi\'nska, Zygmunt Lalak, Marek Lewicki, Pawe{\l} Olszewski
The impact of non-minimally coupled gravity on vacuum stability
null
null
10.1007/JHEP10(2016)004
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider vacuum decay in the presence of a non-minimal coupling to gravity. We extend the usual thin-wall solution to include the non-minimal coupling. We also perform a full numerical study and discuss the validity of the new thin-wall approximation. Implications of a large cosmological constant, whose influence on the geometry boosts the tunnelling rate, are discussed. Our results show that the influence of the non-minimal coupling differs significantly between the cases of Minkowski and deSitter backgrounds. In the latter the decay probability quickly decreases when the coupling grows and in fact the vacuum can be made absolutely stable simply due to introduction of the non-minimal coupling. In the case of Minkowski background the effect is much weaker and the decay rate even increases for small values of the non-minimal coupling.
[ { "created": "Fri, 24 Jun 2016 20:00:00 GMT", "version": "v1" } ]
2016-11-03
[ [ "Czerwińska", "Olga", "" ], [ "Lalak", "Zygmunt", "" ], [ "Lewicki", "Marek", "" ], [ "Olszewski", "Paweł", "" ] ]
We consider vacuum decay in the presence of a non-minimal coupling to gravity. We extend the usual thin-wall solution to include the non-minimal coupling. We also perform a full numerical study and discuss the validity of the new thin-wall approximation. Implications of a large cosmological constant, whose influence on the geometry boosts the tunnelling rate, are discussed. Our results show that the influence of the non-minimal coupling differs significantly between the cases of Minkowski and deSitter backgrounds. In the latter the decay probability quickly decreases when the coupling grows and in fact the vacuum can be made absolutely stable simply due to introduction of the non-minimal coupling. In the case of Minkowski background the effect is much weaker and the decay rate even increases for small values of the non-minimal coupling.
1609.09055
BingRan He
Bing-Ran He
Skyrme model study of proton and neutron properties in a strong magnetic field
5 pages, 6 figures
null
10.1016/j.physletb.2016.12.019
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The proton and neutron properties in a uniform magnetic field are investigated. The Gell-Mann-Nishijima formula is shown to be satisfied for baryon states. It is found that with increasing magnetic field strength, the proton mass first decreases and then increases, while the neutron mass always increases. The ratio between magnetic moment of proton and neutron increases with the increase of the magnetic field strength. With increasing magnetic field strength, the size of proton first increases and then decreases, while the size of neutron always decreases. The present analyse implies that in the core part of the magnetar, the equation of state depend on the magnetic field, which modifies the mass limit of the magnetar.
[ { "created": "Wed, 28 Sep 2016 19:56:12 GMT", "version": "v1" } ]
2017-03-08
[ [ "He", "Bing-Ran", "" ] ]
The proton and neutron properties in a uniform magnetic field are investigated. The Gell-Mann-Nishijima formula is shown to be satisfied for baryon states. It is found that with increasing magnetic field strength, the proton mass first decreases and then increases, while the neutron mass always increases. The ratio between magnetic moment of proton and neutron increases with the increase of the magnetic field strength. With increasing magnetic field strength, the size of proton first increases and then decreases, while the size of neutron always decreases. The present analyse implies that in the core part of the magnetar, the equation of state depend on the magnetic field, which modifies the mass limit of the magnetar.
0911.1256
Christoph Schuck
M. Gl\"uck, E. Reya
Parton Models and the elastic scattering of supersymmetric dark matter off nucleons
6 pages
null
null
DO-TH 09/14
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The consequences of a flavor broken SU(3)_f dynamical parton model are studied in the context of the elastic scattering of supersymmetric dark matter off nucleons. It is shown that the predictions of this model differ considerably from those of the commonly applied `standard' parton model. Some notable properties of the dynamical parton model are finally presented and discussed.
[ { "created": "Fri, 6 Nov 2009 14:11:31 GMT", "version": "v1" } ]
2009-11-09
[ [ "Glück", "M.", "" ], [ "Reya", "E.", "" ] ]
The consequences of a flavor broken SU(3)_f dynamical parton model are studied in the context of the elastic scattering of supersymmetric dark matter off nucleons. It is shown that the predictions of this model differ considerably from those of the commonly applied `standard' parton model. Some notable properties of the dynamical parton model are finally presented and discussed.
1511.05249
Kunihiko Terasaki
Kunihiko Terasaki
Decays of Charmed Vector Mesons --- eta-pi^0 mixing as an origin of isospin non-conservation ---
5 pages, 0 figures
null
null
YITP-15-100
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Pion emitting decays and radiative ones of D^{*+,0} and D_s^{*+} are studied. As the result, the full-width of D^{*0} is predicted, by assuming the isospin symmetry. In addition, the isospin non-conserving D_s^{*+} --> D_s^+ pi^0 decay is investigated under the assumption that it proceeds through the eta-pi^0 mixing.
[ { "created": "Tue, 17 Nov 2015 02:12:29 GMT", "version": "v1" } ]
2015-11-18
[ [ "Terasaki", "Kunihiko", "" ] ]
Pion emitting decays and radiative ones of D^{*+,0} and D_s^{*+} are studied. As the result, the full-width of D^{*0} is predicted, by assuming the isospin symmetry. In addition, the isospin non-conserving D_s^{*+} --> D_s^+ pi^0 decay is investigated under the assumption that it proceeds through the eta-pi^0 mixing.
hep-ph/0211253
Dmitri Kharzeev
D. Kharzeev
What are we learning from RHIC?
11 pages, 6 figures, invited talk given at the XX International Symposium on Lattice Field Theory ``Lattice 2002'', Cambridge, MA, June 24 - 29, 2002
null
10.1016/S0920-5632(03)01488-9
BNL-NT-02/26
hep-ph
null
This talk is an attempt to summarize some of the first results obtained at RHIC. I discuss the significance of these measurements for establishing the properties of hot and dense QCD matter and for understanding the dynamics of the theory at the high parton density, strong color field frontier.
[ { "created": "Fri, 15 Nov 2002 21:30:43 GMT", "version": "v1" } ]
2009-11-07
[ [ "Kharzeev", "D.", "" ] ]
This talk is an attempt to summarize some of the first results obtained at RHIC. I discuss the significance of these measurements for establishing the properties of hot and dense QCD matter and for understanding the dynamics of the theory at the high parton density, strong color field frontier.
hep-ph/9406392
Aneesh V. Manohar
Aneesh V. Manohar and Mark B. Wise
Power Suppressed Corrections to Hadronic Event Shape Variables
(12 pages, 2 figures, uses harvmac and uufiles), UCSD/PTH 94-11
Phys.Lett. B344 (1995) 407-412
10.1016/0370-2693(94)01504-6
null
hep-ph
null
For high energy processes ($M\gg \Lambda_{QCD}$) there are infrared safe hadronic shape variables that have a calculable perturbative expansion in $\alpha_s(M^2)$. However, nonperturbative power suppressed corrections to these variables are not well understood. We use the behavior of large orders of the perturbation expansion to gain insight into the nonperturbative corrections. Our results suggest that certain shape variables have nonperturbative corrections suppressed by fractional powers of $\Lambda_{QCD}^2/M^2$.
[ { "created": "Fri, 24 Jun 1994 19:39:01 GMT", "version": "v1" } ]
2009-10-28
[ [ "Manohar", "Aneesh V.", "" ], [ "Wise", "Mark B.", "" ] ]
For high energy processes ($M\gg \Lambda_{QCD}$) there are infrared safe hadronic shape variables that have a calculable perturbative expansion in $\alpha_s(M^2)$. However, nonperturbative power suppressed corrections to these variables are not well understood. We use the behavior of large orders of the perturbation expansion to gain insight into the nonperturbative corrections. Our results suggest that certain shape variables have nonperturbative corrections suppressed by fractional powers of $\Lambda_{QCD}^2/M^2$.
2006.14825
Wei Wang
Long-Bin Chen, Wei Wang, Ruilin Zhu
Next-to-next-to-leading order corrections to quark Quasi parton distribution functions
9 pages, 1 figure; comments and discussions are warmly welcome; v2: 10 pages, 2 figures, an error corrected, and numerical results added
Phys. Rev. Lett. 126, 072002 (2021)
10.1103/PhysRevLett.126.072002
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the next-to-next-to-leading order (NNLO) calculation of quark quasi parton distribution functions (PDFs) in the large momentum effective theory. The nontrivial factorization at this order is established explicitly and the full analytic matching coefficients between the quasi distribution and the lightcone distribution are derived. We demonstrate that the NNLO numerical contributions can improve the behavior of the extracted PDFs sizably. With the unprecedented precision study of nucleon tomography at the planned electron-ion collider, high precision Lattice QCD simulations with our NNLO results implemented will enable to test the QCD theory and more precise results on the PDFs of nucleons will be obtained.
[ { "created": "Fri, 26 Jun 2020 06:55:36 GMT", "version": "v1" }, { "created": "Tue, 7 Jul 2020 09:16:58 GMT", "version": "v2" }, { "created": "Tue, 8 Sep 2020 16:25:39 GMT", "version": "v3" }, { "created": "Sat, 16 Jan 2021 02:38:45 GMT", "version": "v4" } ]
2021-02-24
[ [ "Chen", "Long-Bin", "" ], [ "Wang", "Wei", "" ], [ "Zhu", "Ruilin", "" ] ]
We present the next-to-next-to-leading order (NNLO) calculation of quark quasi parton distribution functions (PDFs) in the large momentum effective theory. The nontrivial factorization at this order is established explicitly and the full analytic matching coefficients between the quasi distribution and the lightcone distribution are derived. We demonstrate that the NNLO numerical contributions can improve the behavior of the extracted PDFs sizably. With the unprecedented precision study of nucleon tomography at the planned electron-ion collider, high precision Lattice QCD simulations with our NNLO results implemented will enable to test the QCD theory and more precise results on the PDFs of nucleons will be obtained.
2311.13578
Daniel Whiteson
Ryan Holder, John Reddick, Matteo Cremonesi, Doug Berry, Kun Cheng, Matthew Low, Tim M.P. Tait, Daniel Whiteson
Hadronic Mono-$W'$ Probes of Dark Matter at Colliders
6 pages, 8 figures. v2 minor textual updates
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Particle collisions at the energy frontier can probe the nature of invisible dark matter via production in association with recoiling visible objects. We propose a new potential production mode, in which dark matter is produced by the decay of a heavy dark Higgs boson radiated from a heavy $W'$ boson. In such a model, motivated by left-right symmetric theories, dark matter would not be pair produced in association with other recoiling objects due to its lack of direct coupling to quarks or gluons. We study the hadronic decay mode via $W'\rightarrow tb$ and estimate the LHC exclusion sensitivity at 95\% confidence level to be $10^2-10^5$ fb for $W'$ boson masses between 250 and 1750 GeV.
[ { "created": "Wed, 22 Nov 2023 18:32:52 GMT", "version": "v1" }, { "created": "Fri, 3 May 2024 23:39:32 GMT", "version": "v2" } ]
2024-05-07
[ [ "Holder", "Ryan", "" ], [ "Reddick", "John", "" ], [ "Cremonesi", "Matteo", "" ], [ "Berry", "Doug", "" ], [ "Cheng", "Kun", "" ], [ "Low", "Matthew", "" ], [ "Tait", "Tim M. P.", "" ], [ "Whiteson", "Daniel", "" ] ]
Particle collisions at the energy frontier can probe the nature of invisible dark matter via production in association with recoiling visible objects. We propose a new potential production mode, in which dark matter is produced by the decay of a heavy dark Higgs boson radiated from a heavy $W'$ boson. In such a model, motivated by left-right symmetric theories, dark matter would not be pair produced in association with other recoiling objects due to its lack of direct coupling to quarks or gluons. We study the hadronic decay mode via $W'\rightarrow tb$ and estimate the LHC exclusion sensitivity at 95\% confidence level to be $10^2-10^5$ fb for $W'$ boson masses between 250 and 1750 GeV.
hep-ph/9707396
Chi-Sing Lam
Y.J. Feng and C.S. Lam (McGill University)
Evaluation of Multiloop Diagrams via Lightcone Integration
14 pages with eight postscript figures; composed in the Revtex widetext format. This is an expanded and a completely rewritten version replacing the previous one
J.Math.Phys.40:5356-5370,1999
10.1063/1.533035
McGill/97-17
hep-ph
null
We present a systematic method to determine the dominant regions of internal momenta contributing to any two-body high-energy near-forward scattering diagram. Such a knowledge is used to evaluate leading high-energy dependences of loop diagrams. It also gives a good idea where dominant multiparticle cross sections occur.
[ { "created": "Fri, 18 Jul 1997 17:04:16 GMT", "version": "v1" }, { "created": "Sun, 3 May 1998 16:49:22 GMT", "version": "v2" } ]
2014-11-17
[ [ "Feng", "Y. J.", "", "McGill University" ], [ "Lam", "C. S.", "", "McGill University" ] ]
We present a systematic method to determine the dominant regions of internal momenta contributing to any two-body high-energy near-forward scattering diagram. Such a knowledge is used to evaluate leading high-energy dependences of loop diagrams. It also gives a good idea where dominant multiparticle cross sections occur.
0807.3493
Pierpaolo Mastrolia
Pierpaolo Mastrolia
On the Cuts of Scattering Amplitudes
To appear in the proceedings of 9th Workshop on Elementary Particle Theory: Loops and Legs in Quantum Field Theory, Sondershausen, Germany, 20-25 Apr 2008
Nucl.Phys.Proc.Suppl.183:54-59,2008
10.1016/j.nuclphysbps.2008.09.082
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The use of complex analysis for computing one-loop scattering amplitudes is naturally induced by generalised unitarity-cut conditions, fulfilled by complex values of the loop variable. We report on two techniques: the cut-integration with spinor-variables as contour integrals of rational functions; and the use of the Discrete Fourier Transform to optimize the reduction of tensor-integrals to master scalar integrals.
[ { "created": "Tue, 22 Jul 2008 14:50:44 GMT", "version": "v1" } ]
2008-11-26
[ [ "Mastrolia", "Pierpaolo", "" ] ]
The use of complex analysis for computing one-loop scattering amplitudes is naturally induced by generalised unitarity-cut conditions, fulfilled by complex values of the loop variable. We report on two techniques: the cut-integration with spinor-variables as contour integrals of rational functions; and the use of the Discrete Fourier Transform to optimize the reduction of tensor-integrals to master scalar integrals.
hep-ph/0205083
D. M. Ghilencea
D.M. Ghilencea, L.E. Ibanez, N. Irges, F. Quevedo
TeV-Scale Z' Bosons from D-branes
46 pages, LaTeX, JHEP.cls, 21 Figures. minor corrections
JHEP 0208:016,2002
10.1088/1126-6708/2002/08/016
null
hep-ph hep-th
null
Generic D-brane string models of particle physics predict the existence of extra U(1) gauge symmetries beyond hypercharge. These symmetries are not of the E_6 class but rather include the gauging of Baryon and Lepton numbers as well as certain Peccei-Quinn-like symmetries. Some of the U(1)'s have triangle anomalies, but they are cancelled by a Green-Schwarz mechanism. The corresponding gauge bosons typically acquire a mass of order the string scale M_S by combining with two-index antisymmetric fields coming from the closed string sector of the theory. We argue that in string models with a low string scale M_S proportional to 1-10 TeV, the presence of these generic U(1)'s may be amenable to experimental test. Present constraints from electroweak precision data already set important bounds on the mass of these extra gauge bosons. In particular, for large classes of models, rho-parameter constraints imply M_S >= 1.5 TeV. In the present scheme some fraction of the experimentally measured Z^0 mass would be due not to the Higgs mechanism, but rather to the mixing with these closed string fields. We give explicit formulae for recently constructed classes of intersecting D6- and D5-brane models yielding the Standard Model (SM) fermion spectrum.
[ { "created": "Wed, 8 May 2002 18:20:12 GMT", "version": "v1" }, { "created": "Thu, 15 Aug 2002 09:27:58 GMT", "version": "v2" } ]
2011-09-29
[ [ "Ghilencea", "D. M.", "" ], [ "Ibanez", "L. E.", "" ], [ "Irges", "N.", "" ], [ "Quevedo", "F.", "" ] ]
Generic D-brane string models of particle physics predict the existence of extra U(1) gauge symmetries beyond hypercharge. These symmetries are not of the E_6 class but rather include the gauging of Baryon and Lepton numbers as well as certain Peccei-Quinn-like symmetries. Some of the U(1)'s have triangle anomalies, but they are cancelled by a Green-Schwarz mechanism. The corresponding gauge bosons typically acquire a mass of order the string scale M_S by combining with two-index antisymmetric fields coming from the closed string sector of the theory. We argue that in string models with a low string scale M_S proportional to 1-10 TeV, the presence of these generic U(1)'s may be amenable to experimental test. Present constraints from electroweak precision data already set important bounds on the mass of these extra gauge bosons. In particular, for large classes of models, rho-parameter constraints imply M_S >= 1.5 TeV. In the present scheme some fraction of the experimentally measured Z^0 mass would be due not to the Higgs mechanism, but rather to the mixing with these closed string fields. We give explicit formulae for recently constructed classes of intersecting D6- and D5-brane models yielding the Standard Model (SM) fermion spectrum.
hep-ph/0304186
Paul Langacker
Paul Langacker
Structure of the Standard Model
22 pages, 6 figures. First appeared in Precision Tests of the Standard Electroweak Model, 1995
Precision Tests of the Standard Electroweak Model, ed. P. Langacker (World, Singapore, 1995), p15
null
null
hep-ph
null
The structure of the standard model is concisely summarized, including the standard model Lagrangian, spontaneous symmetry breaking, the reexpression of the Lagrangian in terms of mass eigenstates after symmetry breaking, and the gauge interactions. The problems of the standard model are described.
[ { "created": "Sat, 19 Apr 2003 14:16:31 GMT", "version": "v1" } ]
2007-05-23
[ [ "Langacker", "Paul", "" ] ]
The structure of the standard model is concisely summarized, including the standard model Lagrangian, spontaneous symmetry breaking, the reexpression of the Lagrangian in terms of mass eigenstates after symmetry breaking, and the gauge interactions. The problems of the standard model are described.
2312.10450
Tobias Hurth
Tobias Hurth and Robert Szafron
Endpoint divergences in inclusive $\bar B \to X_s \gamma$
Based on talks given by R.S. at SCET 2023, Berkeley, March 2023 and by T.H. at FPCP 2023, Lyon, May 2023
null
null
MITP/23-050
hep-ph
http://creativecommons.org/licenses/by/4.0/
The subleading so-called resolved contributions represent the largest uncertainty in the inclusive decay mode $\bar B \to X_s \gamma$. However there had been no complete proof of factorization of these subleading contributions. This failure of factorisation can be traced back to endpoint divergences and cured by recently proposed refactorisation techniques.
[ { "created": "Sat, 16 Dec 2023 13:48:27 GMT", "version": "v1" } ]
2023-12-19
[ [ "Hurth", "Tobias", "" ], [ "Szafron", "Robert", "" ] ]
The subleading so-called resolved contributions represent the largest uncertainty in the inclusive decay mode $\bar B \to X_s \gamma$. However there had been no complete proof of factorization of these subleading contributions. This failure of factorisation can be traced back to endpoint divergences and cured by recently proposed refactorisation techniques.
hep-ph/0612264
Patricia Ball
Patricia Ball
|V_td/V_ts| from QCD Sum Rules on the Light-Cone
Talk given at CKM06
null
null
IPPP/06/94
hep-ph
null
The dominant theoretical uncertainty in extracting $|V_{td}/V_{ts}|$ from the ratio of branching ratios $R_{\rho/\omega}\equiv\bar{\cal B}(B\to (\rho,\omega)\gamma)/\bar{\cal B}(B\to K^* \gamma)$ is given by the ratio of form factors $\xi_{\rho}\equiv T_1^{B\to K^*}(0)/T_1^{B\to \rho}(0)$. We find $\xi_{\rho}= 1.17\pm 0.09$ from QCD sum rules on the light-cone. Using QCD factorisation for the branching ratios, including the most dominant power-suppressed effects beyond QCD factorisation, and the current experimental results for $R_{\rho/\omega}$, this translates into $|V_{td}/V_{ts}|_{\rm BaBar} = 0.199^{+0.023}_{-0.025}({\rm exp})\pm 0.014 ({\rm th})$, which corresponds to $\gamma_{\rm BaBar} = (61.0^{+13.5}_{-16.0}({\rm th}){}^{+8.9}_{-9.3}({\rm th}))$, and $|V_{td}/V_{ts}|_{\rm Belle} = 0.207^{+0.028}_{-0.033}({\rm exp}) ^{+0.014}_{-0.015}({\rm th})$, $\gamma_{\rm Belle} = (65.7^{+17.3}_{-20.7}({\rm exp})^{+8.9}_{-9.2}({\rm th}))^\circ$.
[ { "created": "Wed, 20 Dec 2006 17:46:58 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ball", "Patricia", "" ] ]
The dominant theoretical uncertainty in extracting $|V_{td}/V_{ts}|$ from the ratio of branching ratios $R_{\rho/\omega}\equiv\bar{\cal B}(B\to (\rho,\omega)\gamma)/\bar{\cal B}(B\to K^* \gamma)$ is given by the ratio of form factors $\xi_{\rho}\equiv T_1^{B\to K^*}(0)/T_1^{B\to \rho}(0)$. We find $\xi_{\rho}= 1.17\pm 0.09$ from QCD sum rules on the light-cone. Using QCD factorisation for the branching ratios, including the most dominant power-suppressed effects beyond QCD factorisation, and the current experimental results for $R_{\rho/\omega}$, this translates into $|V_{td}/V_{ts}|_{\rm BaBar} = 0.199^{+0.023}_{-0.025}({\rm exp})\pm 0.014 ({\rm th})$, which corresponds to $\gamma_{\rm BaBar} = (61.0^{+13.5}_{-16.0}({\rm th}){}^{+8.9}_{-9.3}({\rm th}))$, and $|V_{td}/V_{ts}|_{\rm Belle} = 0.207^{+0.028}_{-0.033}({\rm exp}) ^{+0.014}_{-0.015}({\rm th})$, $\gamma_{\rm Belle} = (65.7^{+17.3}_{-20.7}({\rm exp})^{+8.9}_{-9.2}({\rm th}))^\circ$.
hep-ph/9801345
null
B. L. Ioffe and A.G.Oganesian
Proton spin content and QCD topological susceptibility
8 pages, 2 figures (eps), RevTex
Phys.Rev.D57:6590-6593,1998
10.1103/PhysRevD.57.6590
null
hep-ph
null
The part of the proton spin $\Sigma$ carried by $u, d, s$ quarks is calculated in the framework of the QCD sum rules in the external fields. The operators up to dimension 9 are accounted. An important contribution comes from the operator of dimension 3, which in the limit of massless $u, d, s$ quarks is equal to the derivative of QCD topological susceptibility $\chi^{\prime} (0)$. The comparison with the experimental data on $\Sigma$ gives $\chi^{\prime}(0)= (2.3 \pm 0.6) \times 10^{-3} ~ GeV^2$. The limits on $\Sigma$ and $\chi^{\prime}(0)$ are found from selfconsistency of the sum rule, $\Sigma \ga 0.05,~~ \chi^{\prime} (0) \ga 1.6 \times 10^{-3} ~ GeV^2$. The values of $g_A = 1.37 \pm 0.10$ and $g^8_A = 0.65 \pm 0.15$ are also determined.
[ { "created": "Mon, 19 Jan 1998 17:16:31 GMT", "version": "v1" } ]
2009-12-30
[ [ "Ioffe", "B. L.", "" ], [ "Oganesian", "A. G.", "" ] ]
The part of the proton spin $\Sigma$ carried by $u, d, s$ quarks is calculated in the framework of the QCD sum rules in the external fields. The operators up to dimension 9 are accounted. An important contribution comes from the operator of dimension 3, which in the limit of massless $u, d, s$ quarks is equal to the derivative of QCD topological susceptibility $\chi^{\prime} (0)$. The comparison with the experimental data on $\Sigma$ gives $\chi^{\prime}(0)= (2.3 \pm 0.6) \times 10^{-3} ~ GeV^2$. The limits on $\Sigma$ and $\chi^{\prime}(0)$ are found from selfconsistency of the sum rule, $\Sigma \ga 0.05,~~ \chi^{\prime} (0) \ga 1.6 \times 10^{-3} ~ GeV^2$. The values of $g_A = 1.37 \pm 0.10$ and $g^8_A = 0.65 \pm 0.15$ are also determined.
hep-ph/0111065
Brandon Murakami
Brandon Murakami and James D. Wells (University of California, Davis)
Complementarity of muon-conversion and linear collider-based experiments for lepton-flavor violating U(1) gauge bosons
5 pages, 2 figures. Contributed to APS/DPF/DPB Summer Study on the Future of Particle Physics (Snowmass 2001), Snowmass, Colorado, June 30 to July 21, 2001
eConf C010630 (2001) P303
null
UCD-2001-11
hep-ph
null
In general, attempts to extend the standard model will include extra gauge structure. We parameterize string and technicolor models for a Z' boson with primitive lepton flavor violating interactions. Calculations for its muon conversion rate (mu N -> e N) on Titanium are made and used to show the potential of forthcoming experiments MECO at Brookhaven National Laboratory and PRIME at the Japan Hadron Facility (to be renamed). For reasonable choices of parameters, such U(1) bosons with masses the order 10 TeV and mu-e Z' charge as low as ~10^-5 are demonstrated to be accessible for MECO and PRIME. Also, a demonstration of the complementarity of parameter space coverage for future colliders and muon conversion experiments is given.
[ { "created": "Tue, 6 Nov 2001 23:49:56 GMT", "version": "v1" } ]
2007-05-23
[ [ "Murakami", "Brandon", "", "University of California, Davis" ], [ "Wells", "James D.", "", "University of California, Davis" ] ]
In general, attempts to extend the standard model will include extra gauge structure. We parameterize string and technicolor models for a Z' boson with primitive lepton flavor violating interactions. Calculations for its muon conversion rate (mu N -> e N) on Titanium are made and used to show the potential of forthcoming experiments MECO at Brookhaven National Laboratory and PRIME at the Japan Hadron Facility (to be renamed). For reasonable choices of parameters, such U(1) bosons with masses the order 10 TeV and mu-e Z' charge as low as ~10^-5 are demonstrated to be accessible for MECO and PRIME. Also, a demonstration of the complementarity of parameter space coverage for future colliders and muon conversion experiments is given.
1905.06579
H. B. Benaoum
H. B. Benaoum and S. H. Shaglel
$TeV$-Scale Resonant Leptogenesis with New Scaling Ansatz on Neutrino Dirac Mass Matrix from $A_4$ Flavor Symmetry
25 pages, 10 figues, revised version
International Journal of Modern Physics A35, 2050077, 2020
10.1142/S0217751X20500773
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new scaling ansatz in the neutrino Dirac mass matrix to explain the low energy neutrino oscillations data, baryon number asymmetry and neutrinoless double beta decay. In this work, a full reconstruction of the neutrino Dirac mass matrix has been realized from the low energy neutrino oscillations data based on type-I seesaw mechanism. A concrete model based on $A_4$ flavor symmetry has been considered to generate such a neutrino Dirac mass matrix and imposes a relation between the two scaling factors. In this model, the right-handed Heavy Majorana neutrino masses are quasi-degenerate at TeV mass scales. Extensive numerical analysis studies have been carried out to constrain the parameter space of the model from the low energy neutrino oscillations data. It has been found that the parameter space of the Dirac mass matrix elements lies near or below the MeV region and the scaling factor $|\kappa_1|$ has to be less than 10. Furthermore, we have examined the possibility for simultaneous explanation of both neutrino oscillations data and the observed baryon number asymmetry in the Universe. Such an analysis gives further restrictions on the parameter space of the model, thereby explaining the correct neutrino data as well as the baryon number asymmetry via a resonant leptogenesis scenario. Finally, we show that the allowed space for the effective Majorana neutrino mass $m_{ee}$ is also constrained in order to account for the observed baryon asymmetry.
[ { "created": "Thu, 16 May 2019 07:48:00 GMT", "version": "v1" }, { "created": "Tue, 10 Dec 2019 05:09:11 GMT", "version": "v2" } ]
2020-11-10
[ [ "Benaoum", "H. B.", "" ], [ "Shaglel", "S. H.", "" ] ]
We propose a new scaling ansatz in the neutrino Dirac mass matrix to explain the low energy neutrino oscillations data, baryon number asymmetry and neutrinoless double beta decay. In this work, a full reconstruction of the neutrino Dirac mass matrix has been realized from the low energy neutrino oscillations data based on type-I seesaw mechanism. A concrete model based on $A_4$ flavor symmetry has been considered to generate such a neutrino Dirac mass matrix and imposes a relation between the two scaling factors. In this model, the right-handed Heavy Majorana neutrino masses are quasi-degenerate at TeV mass scales. Extensive numerical analysis studies have been carried out to constrain the parameter space of the model from the low energy neutrino oscillations data. It has been found that the parameter space of the Dirac mass matrix elements lies near or below the MeV region and the scaling factor $|\kappa_1|$ has to be less than 10. Furthermore, we have examined the possibility for simultaneous explanation of both neutrino oscillations data and the observed baryon number asymmetry in the Universe. Such an analysis gives further restrictions on the parameter space of the model, thereby explaining the correct neutrino data as well as the baryon number asymmetry via a resonant leptogenesis scenario. Finally, we show that the allowed space for the effective Majorana neutrino mass $m_{ee}$ is also constrained in order to account for the observed baryon asymmetry.
1809.10152
Giovanni Grilli Di Cortona
Hugues Beauchesne, Enrico Bertuzzo and Giovanni Grilli di Cortona
Dark matter in Hidden Valley models with stable and unstable light dark mesons
22 pages, 8 figures, matches published version
JHEP 1904 (2019) 118
10.1007/JHEP04(2019)118
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is a distinct possibility that a Hidden Valley sector would have a spectrum of light particles consisting of both stable and unstable dark mesons. The simultaneous presence of these two types of particles can lead to novel mechanisms for generating the correct dark matter relic abundance, which in turn can reflect themselves into new exotic signatures at colliders. We study the viability of such sectors for various Hidden Valley models and map the valid parameter space to possible collider signatures. Mediators studied include various scalar bifundamentals and a heavy $Z'$. It is shown that in general bounds from direct and indirect detection can easily be avoided. In most of the allowed parameter space, the relic density is determined by stable mesons annihilating to unstable ones which in turn decay quickly to Standard Model particles. Dark mesons that decay mainly to heavier Standard Model fermions allow for more valid parameter space, though dark mesons are still allowed to decay exclusively to some of the lighter fermions. Possible exotic collider signatures include displaced vertices, emerging jets and semivisible jets.
[ { "created": "Wed, 26 Sep 2018 18:00:03 GMT", "version": "v1" }, { "created": "Mon, 6 May 2019 08:54:40 GMT", "version": "v2" } ]
2019-05-07
[ [ "Beauchesne", "Hugues", "" ], [ "Bertuzzo", "Enrico", "" ], [ "di Cortona", "Giovanni Grilli", "" ] ]
It is a distinct possibility that a Hidden Valley sector would have a spectrum of light particles consisting of both stable and unstable dark mesons. The simultaneous presence of these two types of particles can lead to novel mechanisms for generating the correct dark matter relic abundance, which in turn can reflect themselves into new exotic signatures at colliders. We study the viability of such sectors for various Hidden Valley models and map the valid parameter space to possible collider signatures. Mediators studied include various scalar bifundamentals and a heavy $Z'$. It is shown that in general bounds from direct and indirect detection can easily be avoided. In most of the allowed parameter space, the relic density is determined by stable mesons annihilating to unstable ones which in turn decay quickly to Standard Model particles. Dark mesons that decay mainly to heavier Standard Model fermions allow for more valid parameter space, though dark mesons are still allowed to decay exclusively to some of the lighter fermions. Possible exotic collider signatures include displaced vertices, emerging jets and semivisible jets.
1110.1402
Pilar Coloma
Pilar Coloma, Tracey Li and Silvia Pascoli
Long baseline Super-Beam experiments in Europe within LAGUNA
Latest simulation results included. Some changes in the conclusions. Contribution to NUFACT 11, XIIIth International Workshop on Neutrino Factories, Super beams and Beta beams, 1-6 August 2011, CERN and University of Geneva (Submitted to IOP conference series). 4 pages, 2 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the physics reach of several possible configurations for a Super-Beam experiment in Europe, focusing on the possibilities of discovering $\theta_{13}$, CP violation in the leptonic sector and the ordering of neutrino mass eigenstates. We consider the three different detector technologies: Water \v{C}erenkov, Liquid Argon and Liquid Scintillator, and seven possible sites in Europe which would be able to host such a detector underground. The distances to these sites from CERN, where the beam would be originated, go from 130 km to 2300 km. The neutrino flux is optimized in each case as to match the first oscillation peak for each of the baselines under consideration. We also study the impact of several experimental factors in the performance of each detector technology. These include the influence of the spectral information, the rejection efficiencies for the neutral-current backgrounds, the ratio between running times in neutrino and antineutrino modes and the systematic uncertainties on the signal and backgrounds, among others.
[ { "created": "Thu, 6 Oct 2011 21:58:02 GMT", "version": "v1" }, { "created": "Wed, 12 Oct 2011 19:48:16 GMT", "version": "v2" } ]
2011-10-13
[ [ "Coloma", "Pilar", "" ], [ "Li", "Tracey", "" ], [ "Pascoli", "Silvia", "" ] ]
We explore the physics reach of several possible configurations for a Super-Beam experiment in Europe, focusing on the possibilities of discovering $\theta_{13}$, CP violation in the leptonic sector and the ordering of neutrino mass eigenstates. We consider the three different detector technologies: Water \v{C}erenkov, Liquid Argon and Liquid Scintillator, and seven possible sites in Europe which would be able to host such a detector underground. The distances to these sites from CERN, where the beam would be originated, go from 130 km to 2300 km. The neutrino flux is optimized in each case as to match the first oscillation peak for each of the baselines under consideration. We also study the impact of several experimental factors in the performance of each detector technology. These include the influence of the spectral information, the rejection efficiencies for the neutral-current backgrounds, the ratio between running times in neutrino and antineutrino modes and the systematic uncertainties on the signal and backgrounds, among others.
2210.16015
Vladimir Galkin
R.N. Faustov, V.O. Galkin, E.M. Savchenko
Fully-heavy tetraquark spectroscopy in the relativistic quark model
36 pages, 2 figures
Symmetry 2022, 14(12), 2504
10.3390/sym14122504
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Masses of the ground and excited (1P, 2S, 1D, 2P, 3S) states of the fully-heavy tetraquarks, composed of charm ($c$) and bottom ($b$) quarks and antiquarks, are calculated in the diquark-antidiquark picture within the relativistic quark model based on the quasipotential approach and quantum chromodynamics. The quasipotentials of the quark-quark and diquark-antidiquark interactions are constructed similarly to the previous consideration of mesons and baryons. Relativistic effects are consistently taken into account. A tetraquark is considered as a bound state of a diquark and an antidiquark. The finite size of the diquark is taken into account, using the form factors of the diquark-gluon interaction. It is shown that most of the investigated states of tetraquarks lie above the decay thresholds into a meson pair, as a result they can be observed only as broad resonances. The narrow state X(6900) recently discovered in the di-$J/\psi$ production spectrum by the LHCb, CMS and ATLAS Collaborations corresponds to an excited state of the fully-charmed tetraquark. Other recently discovered exotic heavy resonances X(6200), X(6400), X(6600), X(7200), X(7300) can also be interpreted as the different excitations of the fully-charmed tetraquark.
[ { "created": "Fri, 28 Oct 2022 09:41:46 GMT", "version": "v1" } ]
2022-12-14
[ [ "Faustov", "R. N.", "" ], [ "Galkin", "V. O.", "" ], [ "Savchenko", "E. M.", "" ] ]
Masses of the ground and excited (1P, 2S, 1D, 2P, 3S) states of the fully-heavy tetraquarks, composed of charm ($c$) and bottom ($b$) quarks and antiquarks, are calculated in the diquark-antidiquark picture within the relativistic quark model based on the quasipotential approach and quantum chromodynamics. The quasipotentials of the quark-quark and diquark-antidiquark interactions are constructed similarly to the previous consideration of mesons and baryons. Relativistic effects are consistently taken into account. A tetraquark is considered as a bound state of a diquark and an antidiquark. The finite size of the diquark is taken into account, using the form factors of the diquark-gluon interaction. It is shown that most of the investigated states of tetraquarks lie above the decay thresholds into a meson pair, as a result they can be observed only as broad resonances. The narrow state X(6900) recently discovered in the di-$J/\psi$ production spectrum by the LHCb, CMS and ATLAS Collaborations corresponds to an excited state of the fully-charmed tetraquark. Other recently discovered exotic heavy resonances X(6200), X(6400), X(6600), X(7200), X(7300) can also be interpreted as the different excitations of the fully-charmed tetraquark.
0810.0989
Junjie Cao
Junjie Cao, Jin Min Yang
Current experimental constraints on NMSSM with large lambda
Version in PRD (figs and discussions added)
Phys.Rev.D78:115001,2008
10.1103/PhysRevD.78.115001
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The next-to-minimal supersymmetric model (NMSSM) with a large lambda (the mixing parameter between the singlet and doublet Higgs fields) is well motivated since it can significantly push up the upper bound on the SM-like Higgs boson mass to solve the little hierarchy problem. In this work we examine the current experimental constraints on the NMSSM with a large lambda, which include the direct search for Higgs boson and sparticles at colliders, the indirect constraints from precision electroweak measurements, the cosmic dark matter relic density, the muon anomalous magnetic moment, as well as the stability of the Higgs potential. We find that, with the increase of lambda, parameters like tan-beta, M_A, mu and M_2 are becoming more stringently constrained. It turns out that the maximal reach of lambda is limited by the muon anomalous magnetic moment, and for smuon masses of 200 GeV (500 GeV) the parameter space with lambda > 1.5 (0.6) is excluded.
[ { "created": "Mon, 6 Oct 2008 15:42:25 GMT", "version": "v1" }, { "created": "Sun, 16 Nov 2008 08:09:41 GMT", "version": "v2" } ]
2010-04-15
[ [ "Cao", "Junjie", "" ], [ "Yang", "Jin Min", "" ] ]
The next-to-minimal supersymmetric model (NMSSM) with a large lambda (the mixing parameter between the singlet and doublet Higgs fields) is well motivated since it can significantly push up the upper bound on the SM-like Higgs boson mass to solve the little hierarchy problem. In this work we examine the current experimental constraints on the NMSSM with a large lambda, which include the direct search for Higgs boson and sparticles at colliders, the indirect constraints from precision electroweak measurements, the cosmic dark matter relic density, the muon anomalous magnetic moment, as well as the stability of the Higgs potential. We find that, with the increase of lambda, parameters like tan-beta, M_A, mu and M_2 are becoming more stringently constrained. It turns out that the maximal reach of lambda is limited by the muon anomalous magnetic moment, and for smuon masses of 200 GeV (500 GeV) the parameter space with lambda > 1.5 (0.6) is excluded.
1110.1427
Vladimir Dzhunushaliev
Vladimir Dzhunushaliev
SU(3) glueball gluon condensate
4 pages, 4 fig's
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In a scalar approximation the distribution of a gluon condensate in a glueball is calculated. In this approximation the SU(3) gauge fields are separated on two parts: (1) is the $SU(2) \subset SU(3)$ subgroup, (2) is the coset $SU(3) / SU(2)$. Using an approximate nonperturbative quantization technique two scalar fields are applied for the description of the SU(2) and coset degrees of freedom. In this approach 2-point Green's functions are a bilinear combination of scalar fields and 4-point Green's functions are the product of 2-points Green's functions.
[ { "created": "Fri, 7 Oct 2011 04:52:38 GMT", "version": "v1" } ]
2011-10-10
[ [ "Dzhunushaliev", "Vladimir", "" ] ]
In a scalar approximation the distribution of a gluon condensate in a glueball is calculated. In this approximation the SU(3) gauge fields are separated on two parts: (1) is the $SU(2) \subset SU(3)$ subgroup, (2) is the coset $SU(3) / SU(2)$. Using an approximate nonperturbative quantization technique two scalar fields are applied for the description of the SU(2) and coset degrees of freedom. In this approach 2-point Green's functions are a bilinear combination of scalar fields and 4-point Green's functions are the product of 2-points Green's functions.
0802.4353
Walter Grimus
W. Grimus, L. Lavoura, O.M. Ogreid, P. Osland
The oblique parameters in multi-Higgs-doublet models
18 pages, 5 figures
Nucl.Phys.B801:81-96,2008
10.1016/j.nuclphysb.2008.04.019
UWThPh-2008-4
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present general expressions for the oblique parameters S, T, U, V, W, and X in the SU(2)xU(1) electroweak model with an arbitrary number of scalar SU(2) doublets, with hypercharge 1/2, and an arbitrary number of scalar SU(2) singlets.
[ { "created": "Fri, 29 Feb 2008 10:08:32 GMT", "version": "v1" } ]
2008-11-26
[ [ "Grimus", "W.", "" ], [ "Lavoura", "L.", "" ], [ "Ogreid", "O. M.", "" ], [ "Osland", "P.", "" ] ]
We present general expressions for the oblique parameters S, T, U, V, W, and X in the SU(2)xU(1) electroweak model with an arbitrary number of scalar SU(2) doublets, with hypercharge 1/2, and an arbitrary number of scalar SU(2) singlets.
1412.3525
Peter Zeiler Skands
Peter Skands
Modelling hadronic interactions in HEP MC generators
6 pages. Prepared in the context of the 18th International Symposium on Very High Energy Cosmic Ray Interactions, CERN, 2014
null
null
MCNET-14-25
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
HEP event generators aim to describe high-energy collisions in full exclusive detail. They combine perturbative matrix elements and parton showers with dynamical models of less well-understood phenomena such as hadronization, diffraction, and the so-called underlying event. We briefly summarise some of the main concepts relevant to the modelling of soft/inclusive hadron interactions in MC generators, in particular PYTHIA, with emphasis on questions recently highlighted by LHC data.
[ { "created": "Thu, 11 Dec 2014 03:19:05 GMT", "version": "v1" } ]
2014-12-12
[ [ "Skands", "Peter", "" ] ]
HEP event generators aim to describe high-energy collisions in full exclusive detail. They combine perturbative matrix elements and parton showers with dynamical models of less well-understood phenomena such as hadronization, diffraction, and the so-called underlying event. We briefly summarise some of the main concepts relevant to the modelling of soft/inclusive hadron interactions in MC generators, in particular PYTHIA, with emphasis on questions recently highlighted by LHC data.
hep-ph/0410195
Bhaskar Dutta
R. Arnowitt, Bhaskar Dutta, B. Hu
Some Results in M-Theory Inspired Phenomenology
Talk presented at Deserfest: A Celebration of the Life and Works of Stanley Deser, Ann Arbor, Michigan, 3-5 April, 2004
null
null
null
hep-ph
null
We consider string phenomenological models based on 11D Horava-Witten M-theory with 5 branes in the bulk. If the 5-branes cluster close to the distant orbifold plane (d_n\equiv 1-z_n\simeq 0.1) and if the topological charges of the physical plane vanish (\beta^{(0)}_i=0), then the Witten \epsilon terms (to first order) are correctly small and a qualitative picture of the quark and lepton mass hierarchy arises without significant fine tuning. If right handed neutrinos exist, a possible gravitationally induced cubic holomorphic contribution to the Kahler potential can exist scaled by the 11D Planck mass. These terms give rise to Dirac neutrino masses at the electroweak scale. This mechanism (different from the see-saw mechanism) is seen to account for both the atmospheric and solar neutrino oscillations. The model also gives rise to possible non-universal soft breaking A parameters in the u and d second and third generation quark sector (A_{2,3}^{(u,d)}) which naturally can account for the possible (2.4\sigma) break down of the Standard Model predictions in the recent B-factory data for the B->\phi K_s decays.
[ { "created": "Wed, 13 Oct 2004 15:57:41 GMT", "version": "v1" } ]
2007-05-23
[ [ "Arnowitt", "R.", "" ], [ "Dutta", "Bhaskar", "" ], [ "Hu", "B.", "" ] ]
We consider string phenomenological models based on 11D Horava-Witten M-theory with 5 branes in the bulk. If the 5-branes cluster close to the distant orbifold plane (d_n\equiv 1-z_n\simeq 0.1) and if the topological charges of the physical plane vanish (\beta^{(0)}_i=0), then the Witten \epsilon terms (to first order) are correctly small and a qualitative picture of the quark and lepton mass hierarchy arises without significant fine tuning. If right handed neutrinos exist, a possible gravitationally induced cubic holomorphic contribution to the Kahler potential can exist scaled by the 11D Planck mass. These terms give rise to Dirac neutrino masses at the electroweak scale. This mechanism (different from the see-saw mechanism) is seen to account for both the atmospheric and solar neutrino oscillations. The model also gives rise to possible non-universal soft breaking A parameters in the u and d second and third generation quark sector (A_{2,3}^{(u,d)}) which naturally can account for the possible (2.4\sigma) break down of the Standard Model predictions in the recent B-factory data for the B->\phi K_s decays.
hep-ph/0603238
Ivan Schmidt
Stanley J. Brodsky (SLAC), Boris Kopeliovich, Ivan Schmidt (Universidad Tecnica Federico Santa Maria, Valparaiso), Jacques Soffer (CPT, Marseille)
Diffractive Higgs Production from Intrinsic Heavy Flavors in the Proton
30 pages, 5 figures
Phys.Rev.D73:113005,2006
10.1103/PhysRevD.73.113005
USM-TH-181, CPT-2005/P.021, SLAC-PUB-11784
hep-ph
null
We propose a novel mechanism for exclusive diffractive Higgs production $pp \to p H p $ in which the Higgs boson carries a significant fraction of the projectile proton momentum. This mechanism will provide a clear experimental signal for Higgs production due to the small background in this kinematic region. The key assumption underlying our analysis is the presence of intrinsic heavy flavor components of the proton bound state, whose existence at high light-cone momentum fraction $x$ has growing experimental and theoretical support. We also discuss the implications of this picture for exclusive diffractive quarkonium and other channels.
[ { "created": "Wed, 29 Mar 2006 13:51:54 GMT", "version": "v1" }, { "created": "Mon, 3 Apr 2006 14:08:55 GMT", "version": "v2" } ]
2008-11-26
[ [ "Brodsky", "Stanley J.", "", "SLAC" ], [ "Kopeliovich", "Boris", "", "Universidad Tecnica Federico Santa Maria, Valparaiso" ], [ "Schmidt", "Ivan", "", "Universidad Tecnica Federico Santa Maria, Valparaiso" ], [ "Soffer", "Jacques", "", "CPT,\n Marseille" ] ]
We propose a novel mechanism for exclusive diffractive Higgs production $pp \to p H p $ in which the Higgs boson carries a significant fraction of the projectile proton momentum. This mechanism will provide a clear experimental signal for Higgs production due to the small background in this kinematic region. The key assumption underlying our analysis is the presence of intrinsic heavy flavor components of the proton bound state, whose existence at high light-cone momentum fraction $x$ has growing experimental and theoretical support. We also discuss the implications of this picture for exclusive diffractive quarkonium and other channels.
1609.05860
Oleg Boyarkin
O.M.Boyarkin, G.G.Boyarkina
Influence of solar flares on behavior of solar neutrino flux
10 pages, 0 figures
null
10.1016/j.astropartphys.2016.09.006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Limiting ourselves to two flavor approximation the motion of the neutrino flux in the solar matter and twisting magnetic field is considered. For the neutrino system described by the 4-component wave function $\Psi^T = (\nu_{eL}, \nu_{XL}, {\overline\nu}_{eR}, {\overline\nu}_{XL})$, where $X=\mu, \tau$, an evolution equation is found. Our consideration carries general character, that is, it holds for any SM extensions with massive neutrinos. The resonance transitions of the electron neutrinos are investigated. Factors which influence on the electron neutrino flux, crossing a region of solar flares (SF) are defined. When the SF is absent a terrestrial detector records the electron neutrino flux weakened at the cost both of vacuum oscillations and of the MSW resonance conversion only. On the other hand, the electron neutrino flux passed the SF region in preflare period proves to be further weakened in so far as it undergoes one (Majorana neutrino) or two (Dirac neutrino) additional resonance conversions, apart from the MSW resonance and vacuum oscillations. The hypothesis of the $\nu_e$-induced decays which states that decreasing the beta decay rates of some elements of the periodic table is caused by reduction of the solar neutrino flux is discussed as well. PACS number(s): 12.60.Cn, 14.60.Pg, 96.60.Kx, 95.85.Qx, 96.60.Rd.
[ { "created": "Thu, 15 Sep 2016 09:12:49 GMT", "version": "v1" } ]
2016-10-26
[ [ "Boyarkin", "O. M.", "" ], [ "Boyarkina", "G. G.", "" ] ]
Limiting ourselves to two flavor approximation the motion of the neutrino flux in the solar matter and twisting magnetic field is considered. For the neutrino system described by the 4-component wave function $\Psi^T = (\nu_{eL}, \nu_{XL}, {\overline\nu}_{eR}, {\overline\nu}_{XL})$, where $X=\mu, \tau$, an evolution equation is found. Our consideration carries general character, that is, it holds for any SM extensions with massive neutrinos. The resonance transitions of the electron neutrinos are investigated. Factors which influence on the electron neutrino flux, crossing a region of solar flares (SF) are defined. When the SF is absent a terrestrial detector records the electron neutrino flux weakened at the cost both of vacuum oscillations and of the MSW resonance conversion only. On the other hand, the electron neutrino flux passed the SF region in preflare period proves to be further weakened in so far as it undergoes one (Majorana neutrino) or two (Dirac neutrino) additional resonance conversions, apart from the MSW resonance and vacuum oscillations. The hypothesis of the $\nu_e$-induced decays which states that decreasing the beta decay rates of some elements of the periodic table is caused by reduction of the solar neutrino flux is discussed as well. PACS number(s): 12.60.Cn, 14.60.Pg, 96.60.Kx, 95.85.Qx, 96.60.Rd.
1607.06760
Joao Pedro Espadanal
J. Espadanal, L. Cazon, R. Concei\c{c}\~ao
Sensitivity of EAS measurements to the energy spectrum of muons
in Astroparticle Physics
Astroparticle Physics 86 (2017) 32-40
10.1016/j.astropartphys.2016.11.003
null
hep-ph astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have studied how the energy spectrum of muons at production affects some of the most common measurements related to muons in extensive air shower studies, namely, the number of muons at the ground, the slope of the lateral distribution of muons, the apparent muon production depth, and the arrival time delay of muons at ground. We found that by changing the energy spectrum by an amount consistent with the difference between current models (namely EPOS-LHC and QGSjet-II.04), the muon surface density at ground increases $5\%$ at $20^\circ$ zenith angle and $17\%$ at $60^\circ$ zenith angle. This effect introduces a zenith angle dependence on the reconstructed number of muons which might be experimentally observed. The maximum of the muon production depth distribution at $40^\circ$ increases $\sim10\text{ g/cm}^2$ and $\sim0\text{ g/cm}^2$ at $60^\circ$, which, from pure geometrical considerations, increases the arrival time delay of muons. There is an extra contribution to the delay due to the subluminal velocities of muons of the order of $\sim3$ ns at all zenith angles. Finally, changes introduced in the logarithmic slope of the lateral density function are less than 2%.
[ { "created": "Fri, 22 Jul 2016 17:42:18 GMT", "version": "v1" }, { "created": "Thu, 24 Nov 2016 16:38:07 GMT", "version": "v2" } ]
2016-11-28
[ [ "Espadanal", "J.", "" ], [ "Cazon", "L.", "" ], [ "Conceição", "R.", "" ] ]
We have studied how the energy spectrum of muons at production affects some of the most common measurements related to muons in extensive air shower studies, namely, the number of muons at the ground, the slope of the lateral distribution of muons, the apparent muon production depth, and the arrival time delay of muons at ground. We found that by changing the energy spectrum by an amount consistent with the difference between current models (namely EPOS-LHC and QGSjet-II.04), the muon surface density at ground increases $5\%$ at $20^\circ$ zenith angle and $17\%$ at $60^\circ$ zenith angle. This effect introduces a zenith angle dependence on the reconstructed number of muons which might be experimentally observed. The maximum of the muon production depth distribution at $40^\circ$ increases $\sim10\text{ g/cm}^2$ and $\sim0\text{ g/cm}^2$ at $60^\circ$, which, from pure geometrical considerations, increases the arrival time delay of muons. There is an extra contribution to the delay due to the subluminal velocities of muons of the order of $\sim3$ ns at all zenith angles. Finally, changes introduced in the logarithmic slope of the lateral density function are less than 2%.
2406.06708
Damiano Francesco Giuseppe Fiorillo
Damiano F. G. Fiorillo, Georg G. Raffelt
Theory of neutrino fast flavor evolution. I. Linear response theory and stability conditions
31 pages, 1 figure, plus Appendices
null
null
null
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neutrino-neutrino refraction leads to collective flavor evolution that can include fast flavor conversion, an ingredient still missing in numerical simulations of core-collapse supernovae. We provide a theoretical framework for the linear regime of this phenomenon using the language of response theory. In analogy to electromagnetic waves, we introduce a flavor susceptibility as the linear response to an external flavor field. By requiring self-consistency, this approach leads to the usual dispersion relation for growing modes, but differs from the traditional treatment in that it predicts Landau damping of subluminal collective modes. The new dispersion relation has definite analyticity properties and can be expanded for small growth rates. This approach simplifies and intuitively explains Morinaga's proof of sufficiency for the occurrence of growing modes. We show that weakly growing modes arise as soon as an angular crossing is formed, due to their resonant interaction with individual neutrino modes. For longitudinal plasma waves, a similar resonance causes Landau damping or conversely, the two-stream instability.
[ { "created": "Mon, 10 Jun 2024 18:16:28 GMT", "version": "v1" } ]
2024-06-12
[ [ "Fiorillo", "Damiano F. G.", "" ], [ "Raffelt", "Georg G.", "" ] ]
Neutrino-neutrino refraction leads to collective flavor evolution that can include fast flavor conversion, an ingredient still missing in numerical simulations of core-collapse supernovae. We provide a theoretical framework for the linear regime of this phenomenon using the language of response theory. In analogy to electromagnetic waves, we introduce a flavor susceptibility as the linear response to an external flavor field. By requiring self-consistency, this approach leads to the usual dispersion relation for growing modes, but differs from the traditional treatment in that it predicts Landau damping of subluminal collective modes. The new dispersion relation has definite analyticity properties and can be expanded for small growth rates. This approach simplifies and intuitively explains Morinaga's proof of sufficiency for the occurrence of growing modes. We show that weakly growing modes arise as soon as an angular crossing is formed, due to their resonant interaction with individual neutrino modes. For longitudinal plasma waves, a similar resonance causes Landau damping or conversely, the two-stream instability.
1503.03711
Gui-Jun Ding
Cai-Chang Li, Gui-Jun Ding
Lepton Mixing in $A_5$ Family Symmetry and Generalized CP
47 pages, 10 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study lepton mixing patterns which can be derived from the $A_5$ family symmetry and generalized CP. We find five phenomenologically interesting mixing patterns for which one column of the PMNS matrix is $(\sqrt{\frac{5+\sqrt{5}}{10}},\frac{1}{\sqrt{5+\sqrt{5}}},\frac{1}{\sqrt{5+\sqrt{5}}})^{T}$ (the first column of the golden ratio mixing), $(\sqrt{\frac{5-\sqrt{5}}{10}},\frac{1}{\sqrt{5-\sqrt{5}}},\frac{1}{\sqrt{5-\sqrt{5}}})^{T}$ (the second column of the golden ratio mixing), $(1,1,1)^{T}/\sqrt{3}$ or $(\sqrt{5}+1,-2,\sqrt{5}-1)^{T}/4$. The three lepton mixing angles are determined in terms of a single real parameter $\theta$, and agreement with experimental data can be achieved for certain values of $\theta$. The Dirac CP violating phase is predicted to be trivial or maximal while Majorana phases are trivial. We construct a supersymmetric model based on $A_5$ family symmetry and generalized CP. The lepton mixing is exactly the golden ratio pattern at leading order, and the mixing patterns of case III and case IV are reproduced after higher order corrections are considered.
[ { "created": "Thu, 12 Mar 2015 13:36:00 GMT", "version": "v1" } ]
2015-03-13
[ [ "Li", "Cai-Chang", "" ], [ "Ding", "Gui-Jun", "" ] ]
We study lepton mixing patterns which can be derived from the $A_5$ family symmetry and generalized CP. We find five phenomenologically interesting mixing patterns for which one column of the PMNS matrix is $(\sqrt{\frac{5+\sqrt{5}}{10}},\frac{1}{\sqrt{5+\sqrt{5}}},\frac{1}{\sqrt{5+\sqrt{5}}})^{T}$ (the first column of the golden ratio mixing), $(\sqrt{\frac{5-\sqrt{5}}{10}},\frac{1}{\sqrt{5-\sqrt{5}}},\frac{1}{\sqrt{5-\sqrt{5}}})^{T}$ (the second column of the golden ratio mixing), $(1,1,1)^{T}/\sqrt{3}$ or $(\sqrt{5}+1,-2,\sqrt{5}-1)^{T}/4$. The three lepton mixing angles are determined in terms of a single real parameter $\theta$, and agreement with experimental data can be achieved for certain values of $\theta$. The Dirac CP violating phase is predicted to be trivial or maximal while Majorana phases are trivial. We construct a supersymmetric model based on $A_5$ family symmetry and generalized CP. The lepton mixing is exactly the golden ratio pattern at leading order, and the mixing patterns of case III and case IV are reproduced after higher order corrections are considered.
1210.3011
James Maxin
Tianjun Li, James A. Maxin, Dimitri V. Nanopoulos, and Joel W. Walker
Primordial Synthesis: F-SU(5) SUSY Multijets, 145-150 GeV LSP, Proton & Rare Decays, 125 GeV Higgs Boson, and WMAP7
14 Pages, 3 Figures, 3 Tables
null
null
ACT-13-12; MIFPA-12-37
hep-ph astro-ph.CO hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the first ATLAS Collaboration 8 TeV 5.8/fb supersymmetry (SUSY) multijet data observations in the context of No-Scale Flipped SU(5) with extra TeV-Scale vector-like flippon multiplets, dubbed F-SU(5), finding that the recent 8 TeV collider data is statistically consistent with our prior 7 TeV results. Furthermore, we synthesize all currently ongoing experiments searching for beyond the Standard Model (BSM) physics with this fit to the 8 TeV data, establishing a suggestive global coherence within a No-Scale F-SU(5) high-energy framework. The SUSY mass scale consistent with all BSM data consists of the region of the F-SU(5) model space within 660 ~< M_{1/2} ~< 760 GeV, which corresponds to sparticle masses of 133 ~< M(chi_1^0) ~< 160 GeV, 725 ~< M(t_1) ~< 845 GeV, and 890 ~< M(g) ~< 1025 GeV. We suggest that the tight non-trivial correspondence between the SUSY multijets, direct and indirect searches for dark matter, proton decay, rare-decay processes, the observed Higgs boson mass, and the measured dark matter relic density, is strongly indicative of a deeper fundamental relationship. We additionally suggest a simple mechanism for enhancing the capture efficiency of F-SU(5) SUSY multijets, which results in a 93% suppression in ATLAS reported background events, but only a 27% decrease in Monte Carlo simulated F-SU(5) multijet events.
[ { "created": "Wed, 10 Oct 2012 19:35:41 GMT", "version": "v1" } ]
2012-10-11
[ [ "Li", "Tianjun", "" ], [ "Maxin", "James A.", "" ], [ "Nanopoulos", "Dimitri V.", "" ], [ "Walker", "Joel W.", "" ] ]
We examine the first ATLAS Collaboration 8 TeV 5.8/fb supersymmetry (SUSY) multijet data observations in the context of No-Scale Flipped SU(5) with extra TeV-Scale vector-like flippon multiplets, dubbed F-SU(5), finding that the recent 8 TeV collider data is statistically consistent with our prior 7 TeV results. Furthermore, we synthesize all currently ongoing experiments searching for beyond the Standard Model (BSM) physics with this fit to the 8 TeV data, establishing a suggestive global coherence within a No-Scale F-SU(5) high-energy framework. The SUSY mass scale consistent with all BSM data consists of the region of the F-SU(5) model space within 660 ~< M_{1/2} ~< 760 GeV, which corresponds to sparticle masses of 133 ~< M(chi_1^0) ~< 160 GeV, 725 ~< M(t_1) ~< 845 GeV, and 890 ~< M(g) ~< 1025 GeV. We suggest that the tight non-trivial correspondence between the SUSY multijets, direct and indirect searches for dark matter, proton decay, rare-decay processes, the observed Higgs boson mass, and the measured dark matter relic density, is strongly indicative of a deeper fundamental relationship. We additionally suggest a simple mechanism for enhancing the capture efficiency of F-SU(5) SUSY multijets, which results in a 93% suppression in ATLAS reported background events, but only a 27% decrease in Monte Carlo simulated F-SU(5) multijet events.
hep-ph/9408391
null
A.Bottino, N.Fornengo, G.Mignola and L.Moscoso
Signals of Neutralino Dark Matter from Earth and Sun
14 pages in Plain TeX, 14 figures included in a separate uuencoded tarred-compressed Postscript file; Report number: DFTT 34/95; To appear in Astroparticle Physics
Astropart.Phys.3:65-76,1995
10.1016/0927-6505(94)00028-2
null
hep-ph astro-ph
null
We evaluate the fluxes of up--going muons detectable in a neutrino telescope and due to the annihilation of relic neutralinos in the Earth and in the Sun, taking realistically into account the fact that neutralinos might provide only a fraction of the local (solar neighbourhood) dark matter (DM). We determine the relation between the exposure $A t$ of the neutrino telescope ($A$ being the telescope area, $t$ the live time) and the explorable range of the neutralino mass and composition, when the signal--to--background ratio is optimized by an appropriate angular selection.
[ { "created": "Tue, 30 Aug 1994 16:12:16 GMT", "version": "v1" } ]
2011-05-23
[ [ "Bottino", "A.", "" ], [ "Fornengo", "N.", "" ], [ "Mignola", "G.", "" ], [ "Moscoso", "L.", "" ] ]
We evaluate the fluxes of up--going muons detectable in a neutrino telescope and due to the annihilation of relic neutralinos in the Earth and in the Sun, taking realistically into account the fact that neutralinos might provide only a fraction of the local (solar neighbourhood) dark matter (DM). We determine the relation between the exposure $A t$ of the neutrino telescope ($A$ being the telescope area, $t$ the live time) and the explorable range of the neutralino mass and composition, when the signal--to--background ratio is optimized by an appropriate angular selection.
hep-ph/0609312
Alan D. Martin
V.A. Khoze, A.D. Martin and M.G. Ryskin
The extraction of the bare triple-Pomeron vertex; a crucial ingredient for diffraction
10 pages, 3 figures
Phys.Lett.B643:93-97,2006
10.1016/j.physletb.2006.10.031
IPPP/06/65, DCPT/06/130
hep-ph
null
The triple-Pomeron coupling lies at the heart of the predictions for high energy diffractive processes. We explain why the existing determinations, which use single-particle inclusive hadronic data a+b -> a+Y, underestimate the value of the bare coupling, due to the neglect of soft rescattering which populates the rapidity gaps. We describe how data for the process gamma+p -> J/psi +Y can be used to give a much more reliable estimate of the bare coupling. We use the existing, fragmentary, J/psi data from HERA to show that the triple-Pomeron coupling is probably about 3 times larger than the previous determinations. We emphasize the importance of an explicit measurement of the mass spectrum of the Y system which accompanies J/psi production at HERA. The consequences for ultra high energy cosmic ray showers are mentioned.
[ { "created": "Fri, 29 Sep 2006 15:47:06 GMT", "version": "v1" } ]
2008-11-26
[ [ "Khoze", "V. A.", "" ], [ "Martin", "A. D.", "" ], [ "Ryskin", "M. G.", "" ] ]
The triple-Pomeron coupling lies at the heart of the predictions for high energy diffractive processes. We explain why the existing determinations, which use single-particle inclusive hadronic data a+b -> a+Y, underestimate the value of the bare coupling, due to the neglect of soft rescattering which populates the rapidity gaps. We describe how data for the process gamma+p -> J/psi +Y can be used to give a much more reliable estimate of the bare coupling. We use the existing, fragmentary, J/psi data from HERA to show that the triple-Pomeron coupling is probably about 3 times larger than the previous determinations. We emphasize the importance of an explicit measurement of the mass spectrum of the Y system which accompanies J/psi production at HERA. The consequences for ultra high energy cosmic ray showers are mentioned.
hep-ph/0008137
Savely G. Karshenboim
Savely G. Karshenboim (D. I. Mendeleev Institute for Metrology, St. Petersburg and Max-Planck-Institut fuer Quantenoptik, Garching)
The hydrogen Lamb shift and the proton radius
An invited talk presented at workshop `Hadronic Atoms and Positronium in the Stardard Model' (Dubna, 1998) 8 pages, 3 figures
Proceedings of the International Workshop `Hadronic Atoms and Positronium in the Standard Model'. Ed. By M. A. Ivanov et al., Dubna (1998) 224-231
null
null
hep-ph physics.atom-ph
null
The Lamb shift measurement and theory are now both a dynamically developing field and we give a review of the current data. Critical comparison of theory and experiment can be done using a value of the proton charge radius and we pay attention to several results of its determination.
[ { "created": "Mon, 14 Aug 2000 16:07:02 GMT", "version": "v1" } ]
2007-05-23
[ [ "Karshenboim", "Savely G.", "", "D. I. Mendeleev Institute for Metrology, St.\n Petersburg and Max-Planck-Institut fuer Quantenoptik, Garching" ] ]
The Lamb shift measurement and theory are now both a dynamically developing field and we give a review of the current data. Critical comparison of theory and experiment can be done using a value of the proton charge radius and we pay attention to several results of its determination.
2004.03764
Hao Sun
Xuan Luo, Hao Sun
Transverse single spin asymmetry $A_{UT}^{\sin(\phi_h-\phi_S)}$ for single hadron production in SIDIS
12 pages, 9 figures, arxiv version updated
Phys. Rev. D 101, 074016 (2020)
10.1103/PhysRevD.101.074016
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we study the single spin asymmetry $A_{UT}^{\sin(\phi_h-\phi_S)}$ of a single hadron production in semi-inclusive deep inelastic scattering (SIDIS) within the framework of transverse momentum dependent (TMD) factorization up to next-to-leading logarithmic (NLL) order of QCD. The asymmetry is contributed by the convolution of the Sivers function and the unpolarized fragmentation function. Specifically, the Sivers function in the coordinate space and perturbative region can be represented as the convolution of the $C$-coefficients and the corresponding collinear correlation functions, among which the Qiu-Sterman function is the most relevant one. We perform a detailed phenomenological analysis of the Sivers asymmetry at the kinematics of the HERMES and the COMPASS measurements. It is found that the obtained $x_B$-, $z_h$- and $P_{h\perp}$-dependent asymmetries are basically consistent with the HERMES and the COMPASS measurements.
[ { "created": "Wed, 8 Apr 2020 01:19:37 GMT", "version": "v1" }, { "created": "Mon, 13 Apr 2020 00:36:57 GMT", "version": "v2" } ]
2020-04-22
[ [ "Luo", "Xuan", "" ], [ "Sun", "Hao", "" ] ]
In this paper we study the single spin asymmetry $A_{UT}^{\sin(\phi_h-\phi_S)}$ of a single hadron production in semi-inclusive deep inelastic scattering (SIDIS) within the framework of transverse momentum dependent (TMD) factorization up to next-to-leading logarithmic (NLL) order of QCD. The asymmetry is contributed by the convolution of the Sivers function and the unpolarized fragmentation function. Specifically, the Sivers function in the coordinate space and perturbative region can be represented as the convolution of the $C$-coefficients and the corresponding collinear correlation functions, among which the Qiu-Sterman function is the most relevant one. We perform a detailed phenomenological analysis of the Sivers asymmetry at the kinematics of the HERMES and the COMPASS measurements. It is found that the obtained $x_B$-, $z_h$- and $P_{h\perp}$-dependent asymmetries are basically consistent with the HERMES and the COMPASS measurements.
hep-ph/0012150
Gorbunov
D.Gorbunov, V.Ilyin, B.Mele
Sgoldstino events in top decays at LHC
Standard LaTeX, 11 pages, 4 figures, one reference added
Phys.Lett.B502:181-188,2001
10.1016/S0370-2693(01)00157-5
null
hep-ph
null
We study top-quark decays in models with light sgoldstinos. The off-diagonal entries in the squark mass matrices can lead to FCNC top two-body decays into sgoldstinos and u(c) quarks. We compute the rates for these decays and discuss the corresponding signatures that could manifest the presence of sgoldstinos in top decays at LHC. We expect that a supersymmetry breaking scale $\sqrt{F}$ up to a scale of order 10 TeV could be probed through this process, for a maximal squark mixing with the third generation. Justified by our preliminary analysis, a thorough study of the corresponding signal versus background and systematics in the LHC environment would be most welcome, in order to accurately assess the potential of this promising process in determining $\sqrt{F}$.
[ { "created": "Wed, 13 Dec 2000 14:10:05 GMT", "version": "v1" }, { "created": "Wed, 20 Dec 2000 19:54:12 GMT", "version": "v2" } ]
2009-11-19
[ [ "Gorbunov", "D.", "" ], [ "Ilyin", "V.", "" ], [ "Mele", "B.", "" ] ]
We study top-quark decays in models with light sgoldstinos. The off-diagonal entries in the squark mass matrices can lead to FCNC top two-body decays into sgoldstinos and u(c) quarks. We compute the rates for these decays and discuss the corresponding signatures that could manifest the presence of sgoldstinos in top decays at LHC. We expect that a supersymmetry breaking scale $\sqrt{F}$ up to a scale of order 10 TeV could be probed through this process, for a maximal squark mixing with the third generation. Justified by our preliminary analysis, a thorough study of the corresponding signal versus background and systematics in the LHC environment would be most welcome, in order to accurately assess the potential of this promising process in determining $\sqrt{F}$.
2012.11751
Vladimir Baryshevsky
V. G. Baryshevsky and P. I. Porshnev
Pseudoscalar corrections to spin motion equation, search for electric dipole moment and muon magnetic (g-2) factor
27 pages
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The spin dynamics in constant electromagnetic fields is described by the Bargmann-Michel-Telegdi equation which can be upgraded with anomalous magnetic and electric dipole moments. The upgraded equation remains self-consistent, Lorentz-covariant and gauge-invariant. It and its different forms have been confirmed in numerous experiments to high degree of accuracy. We have recently derived the spin motion equation within the Wentzel-Kramers-Brillouin weak-field approximation which adds a pseudoscalar correction to the BMT equation. The upgraded equation is again self-consistent, Lorentz-covariant, gauge-invariant, and free of unwanted artifacts. The pseudoscalar correction is expected to be small, and might become important in hypersensitive experiments, like the measurements of electric dipole moments which are themselves related to pseudoscalar quantities. It also becomes possible to explain why EDMs are so difficult to measure, since this correction term might lead to the effective screening of electric dipole moments. Within the same model, it is possible to explain the discrepancy between experimental and theoretical values of muon magnetic anomaly under assumption that the pseudoscalar correction is the dominant source of this discrepancy.
[ { "created": "Mon, 21 Dec 2020 23:44:36 GMT", "version": "v1" } ]
2021-01-18
[ [ "Baryshevsky", "V. G.", "" ], [ "Porshnev", "P. I.", "" ] ]
The spin dynamics in constant electromagnetic fields is described by the Bargmann-Michel-Telegdi equation which can be upgraded with anomalous magnetic and electric dipole moments. The upgraded equation remains self-consistent, Lorentz-covariant and gauge-invariant. It and its different forms have been confirmed in numerous experiments to high degree of accuracy. We have recently derived the spin motion equation within the Wentzel-Kramers-Brillouin weak-field approximation which adds a pseudoscalar correction to the BMT equation. The upgraded equation is again self-consistent, Lorentz-covariant, gauge-invariant, and free of unwanted artifacts. The pseudoscalar correction is expected to be small, and might become important in hypersensitive experiments, like the measurements of electric dipole moments which are themselves related to pseudoscalar quantities. It also becomes possible to explain why EDMs are so difficult to measure, since this correction term might lead to the effective screening of electric dipole moments. Within the same model, it is possible to explain the discrepancy between experimental and theoretical values of muon magnetic anomaly under assumption that the pseudoscalar correction is the dominant source of this discrepancy.
2103.15185
Muneto Nitta
Yuki Fujimoto and Muneto Nitta
Topological confinement of vortices in two-flavor dense QCD
35 pages, 3 figures
JHEP 2109 (2021) 192
10.1007/JHEP09(2021)192
null
hep-ph cond-mat.supr-con hep-th
http://creativecommons.org/licenses/by/4.0/
We find a novel confinement mechanism in the two-flavor dense quark matter proposed recently, that consists of the 2SC condensates and the $P$-wave diquark condensates of $d$-quarks. This quark matter exhibiting color superconductivity as well as superfluidity is classified into two phases; confined and deconfined phases of vortices. We establish that the criterion of the confinement is color neutrality of Aharonov-Bohm (AB) phases: vortices exhibiting color non-singlet AB phases are confined by the so-called AB defects to form color-singlet bound states. In the deconfined phase, the most stable vortices are non-Abelian Alice strings, which are superfluid vortices with fractional circulation and non-Abelian color magnetic fluxes therein, exhibiting color non-singlet AB phases. On the other hand, in the confined phase, these non-Abelian vortices are confined to either a baryonic or mesonic bound state in which constituent vortices are connected by AB defects. The baryonic bound state consists of three non-Abelian Alice strings with different color magnetic fluxes with the total flux canceled out connected by a domain wall junction, while the mesonic bound state consists of two non-Abelian Alice strings with the same color magnetic fluxes connected by a single domain wall. Interestingly, the latter contains a color magnetic flux in its core, but this can exist because of color neutrality of its AB phase.
[ { "created": "Sun, 28 Mar 2021 17:47:52 GMT", "version": "v1" } ]
2021-10-06
[ [ "Fujimoto", "Yuki", "" ], [ "Nitta", "Muneto", "" ] ]
We find a novel confinement mechanism in the two-flavor dense quark matter proposed recently, that consists of the 2SC condensates and the $P$-wave diquark condensates of $d$-quarks. This quark matter exhibiting color superconductivity as well as superfluidity is classified into two phases; confined and deconfined phases of vortices. We establish that the criterion of the confinement is color neutrality of Aharonov-Bohm (AB) phases: vortices exhibiting color non-singlet AB phases are confined by the so-called AB defects to form color-singlet bound states. In the deconfined phase, the most stable vortices are non-Abelian Alice strings, which are superfluid vortices with fractional circulation and non-Abelian color magnetic fluxes therein, exhibiting color non-singlet AB phases. On the other hand, in the confined phase, these non-Abelian vortices are confined to either a baryonic or mesonic bound state in which constituent vortices are connected by AB defects. The baryonic bound state consists of three non-Abelian Alice strings with different color magnetic fluxes with the total flux canceled out connected by a domain wall junction, while the mesonic bound state consists of two non-Abelian Alice strings with the same color magnetic fluxes connected by a single domain wall. Interestingly, the latter contains a color magnetic flux in its core, but this can exist because of color neutrality of its AB phase.
hep-ph/0009228
Sharon Jensen
Stanley J. Brodsky
The Light-Cone Fock Expansion in Quantum Chromodynamics
Presented at VII Hadron Physics 2000, Caraguatatuba, Sao Paulo, Brazil, April 10-15, 2000
null
10.1142/9789812811653_0001
SLAC-PUB-8627
hep-ph
null
A fundamental question in QCD is the non-perturbative structure of hadrons at the amplitude level--not just the single-particle flavor, momentum, and helicity distributions of the quark constituents, but also the multi-quark, gluonic, and hidden-color correlations intrinsic to hadronic and nuclear wavefunctions. The light-cone Fock-state representation of QCD encodes the properties of a hadrons in terms of frame-independent wavefunctions. A number of applications are discussed, including semileptonic B decays, deeply virtual Compton scattering, and dynamical higher twist effects in inclusive reactions. A new type of jet production reaction, "self-resolving diffractive interactions" can provide direct information on the light-cone wavefunctions of hadrons in terms of their quark and gluon degrees of freedom as well as the composition of nuclei in terms of their nucleon and mesonic degrees of freedom. The relation of the intrinsic sea to the light-cone wavefunctions is discussed. The physics of light-cone wavefunctions is illustrated for the quantum fluctuations of an electron.
[ { "created": "Tue, 19 Sep 2000 23:56:42 GMT", "version": "v1" } ]
2017-08-23
[ [ "Brodsky", "Stanley J.", "" ] ]
A fundamental question in QCD is the non-perturbative structure of hadrons at the amplitude level--not just the single-particle flavor, momentum, and helicity distributions of the quark constituents, but also the multi-quark, gluonic, and hidden-color correlations intrinsic to hadronic and nuclear wavefunctions. The light-cone Fock-state representation of QCD encodes the properties of a hadrons in terms of frame-independent wavefunctions. A number of applications are discussed, including semileptonic B decays, deeply virtual Compton scattering, and dynamical higher twist effects in inclusive reactions. A new type of jet production reaction, "self-resolving diffractive interactions" can provide direct information on the light-cone wavefunctions of hadrons in terms of their quark and gluon degrees of freedom as well as the composition of nuclei in terms of their nucleon and mesonic degrees of freedom. The relation of the intrinsic sea to the light-cone wavefunctions is discussed. The physics of light-cone wavefunctions is illustrated for the quantum fluctuations of an electron.
hep-ph/0503063
Nigel Glover
T.G. Birthwright, E.W.N. Glover, V.V. Khoze and P. Marquard (Durham U., IPPP)
Multi-Gluon Collinear Limits from MHV diagrams
28 pages, six figures, JHEP3 class
JHEP0505:013,2005
10.1088/1126-6708/2005/05/013
DCPT/05/04, IPPP/05/02
hep-ph hep-th
null
We consider the multi-collinear limit of multi-gluon QCD amplitudes at tree level. We use the MHV rules for constructing colour ordered tree amplitudes and the general collinear factorization formula to derive timelike splitting functions that are valid for specific numbers of negative helicity gluons and an arbitrary number of positive helicity gluons (or vice versa). As an example we present new results describing the collinear limits of up to six gluons.
[ { "created": "Mon, 7 Mar 2005 17:02:36 GMT", "version": "v1" } ]
2009-11-11
[ [ "Birthwright", "T. G.", "", "Durham\n U., IPPP" ], [ "Glover", "E. W. N.", "", "Durham\n U., IPPP" ], [ "Khoze", "V. V.", "", "Durham\n U., IPPP" ], [ "Marquard", "P.", "", "Durham\n U., IPPP" ] ]
We consider the multi-collinear limit of multi-gluon QCD amplitudes at tree level. We use the MHV rules for constructing colour ordered tree amplitudes and the general collinear factorization formula to derive timelike splitting functions that are valid for specific numbers of negative helicity gluons and an arbitrary number of positive helicity gluons (or vice versa). As an example we present new results describing the collinear limits of up to six gluons.
1211.1922
Francesco D'Eramo
Francesco D'Eramo, Mindaugas Lekaveckas, Hong Liu, Krishna Rajagopal
Momentum Broadening in Weakly Coupled Quark-Gluon Plasma (with a view to finding the quasiparticles within liquid quark-gluon plasma)
34 pages, 17 figures. v2: discussion extended and Appendix added to connect our calculation to the Boltzmann equation approach and to further connect it to previous results in the literature. References added
null
10.1007/JHEP05(2013)031
MIT-CTP-4400, UCB-PTH-12/14, CERN-PH-TH/2012-303
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate P(k_\perp), the probability distribution for an energetic parton that propagates for a distance L through a medium without radiating to pick up transverse momentum k_\perp, for a medium consisting of weakly coupled quark-gluon plasma. We use full or HTL self-energies in appropriate regimes, resumming each in order to find the leading large-L behavior. The jet quenching parameter \hat q is the second moment of P(k_\perp), and we compare our results to other determinations of this quantity in the literature, although we emphasize the importance of looking at P(k_\perp) in its entirety. We compare our results for P(k_\perp) in weakly coupled quark-gluon plasma to expectations from holographic calculations that assume a plasma that is strongly coupled at all length scales. We find that the shape of P(k_\perp) at modest k_\perp may not be very different in weakly coupled and strongly coupled plasmas, but we find that P(k_\perp) must be parametrically larger in a weakly coupled plasma than in a strongly coupled plasma at large enough k_\perp. This means that by looking for rare (but not exponentially rare) large-angle deflections of the jet resulting from a parton produced initially back-to-back with a hard photon, experimentalists can find the weakly coupled short-distance quark and gluon quasiparticles within the strongly coupled liquid quark-gluon plasma produced in heavy ion collisions, much as Rutherford found nuclei within atoms or Friedman, Kendall and Taylor found quarks within nucleons.
[ { "created": "Thu, 8 Nov 2012 17:51:34 GMT", "version": "v1" }, { "created": "Mon, 17 Dec 2012 21:45:40 GMT", "version": "v2" } ]
2015-06-12
[ [ "D'Eramo", "Francesco", "" ], [ "Lekaveckas", "Mindaugas", "" ], [ "Liu", "Hong", "" ], [ "Rajagopal", "Krishna", "" ] ]
We calculate P(k_\perp), the probability distribution for an energetic parton that propagates for a distance L through a medium without radiating to pick up transverse momentum k_\perp, for a medium consisting of weakly coupled quark-gluon plasma. We use full or HTL self-energies in appropriate regimes, resumming each in order to find the leading large-L behavior. The jet quenching parameter \hat q is the second moment of P(k_\perp), and we compare our results to other determinations of this quantity in the literature, although we emphasize the importance of looking at P(k_\perp) in its entirety. We compare our results for P(k_\perp) in weakly coupled quark-gluon plasma to expectations from holographic calculations that assume a plasma that is strongly coupled at all length scales. We find that the shape of P(k_\perp) at modest k_\perp may not be very different in weakly coupled and strongly coupled plasmas, but we find that P(k_\perp) must be parametrically larger in a weakly coupled plasma than in a strongly coupled plasma at large enough k_\perp. This means that by looking for rare (but not exponentially rare) large-angle deflections of the jet resulting from a parton produced initially back-to-back with a hard photon, experimentalists can find the weakly coupled short-distance quark and gluon quasiparticles within the strongly coupled liquid quark-gluon plasma produced in heavy ion collisions, much as Rutherford found nuclei within atoms or Friedman, Kendall and Taylor found quarks within nucleons.
2003.05433
Michael E. Peskin
Michael E. Peskin
Precision Theory of Electroweak Interactions
24 pages, 13 figures; v2: minor reference corrections
null
null
SLAC-PUB-17516
hep-ph physics.hist-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
As a part of the celebration of 50 years of the Standard Model of particle physics, I present a brief history of the precision theory of electroweak interactions. I emphasize in particular the theoretical preparations for the LEP program and the prediction of m_t and m_h from the electroweak precision data. [to appear in the proceedings of the SM@50 Symposium, Case Western Reserve University, June 1-4, 2018]
[ { "created": "Wed, 11 Mar 2020 17:48:52 GMT", "version": "v1" }, { "created": "Sat, 21 Mar 2020 19:08:28 GMT", "version": "v2" } ]
2020-03-24
[ [ "Peskin", "Michael E.", "" ] ]
As a part of the celebration of 50 years of the Standard Model of particle physics, I present a brief history of the precision theory of electroweak interactions. I emphasize in particular the theoretical preparations for the LEP program and the prediction of m_t and m_h from the electroweak precision data. [to appear in the proceedings of the SM@50 Symposium, Case Western Reserve University, June 1-4, 2018]
2201.07702
Xiaojun Yao
Xiaojun Yao
Quarkonium Suppression in the Open Quantum System Approach
4 pages, leading parallel contribution to the proceedings of the 19th International Conference on Hadron Spectroscopy and Structure (Hadron 2021)
null
null
MIT-CTP/5393
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Quarkonium suppression in relativistic heavy ion collisions has been studied experimentally for decades to probe the properties of the quark-gluon plasma. For this purpose, complete theoretical understanding of the time evolution of quarkonium inside the quark-gluon plasma is needed but challenging. Here I review recent progress in applying the open quantum system framework to describe the real-time dynamics of quarkonium, with a focus on the gauge-invariant chromoelectric field correlators of the plasma that control the dynamics.
[ { "created": "Wed, 19 Jan 2022 16:39:28 GMT", "version": "v1" } ]
2022-01-20
[ [ "Yao", "Xiaojun", "" ] ]
Quarkonium suppression in relativistic heavy ion collisions has been studied experimentally for decades to probe the properties of the quark-gluon plasma. For this purpose, complete theoretical understanding of the time evolution of quarkonium inside the quark-gluon plasma is needed but challenging. Here I review recent progress in applying the open quantum system framework to describe the real-time dynamics of quarkonium, with a focus on the gauge-invariant chromoelectric field correlators of the plasma that control the dynamics.
hep-ph/0105119
Amitava Raychaudhuri
Rathin Adhikari, Arunansu Sil, Amitava Raychaudhuri (University of Calcutta and Jadavpur University)
A new three flavor oscillation solution of the solar neutrino deficit in R-parity violating supersymmetry
Latex, 7 pages, 1 ps figure, Minor changes in presentation, typos corrected
Eur.Phys.J.C25:125-130,2002
10.1007/s10052-002-0946-6
null
hep-ph astro-ph hep-ex
null
We present a solution of the solar neutrino deficit using three flavors of neutrinos within the R-parity non-conserving supersymmetric model. In vacuum, mass and mixing is restricted to the nu(mu)-nu(tau) sector only, which we choose in consistency with the requirements of the atmospheric neutrino anomaly. The nu(e) is massless and unmixed. The flavor changing and flavor diagonal neutral currents present in the model and an energy-dependent resonance-induced nu(e)-nu(mu) mixing in the sun result in the new solution to the solar neutrino problem. The best fit to the solar neutrino rates and spectrum (1258-day SK data) requires a mass square difference of 10^{-5} eV^2 in vacuum between the two lightest neutrinos. This solution cannot accommodate a significant day-night effect for solar neutrinos.
[ { "created": "Mon, 14 May 2001 13:34:21 GMT", "version": "v1" }, { "created": "Sat, 19 May 2001 07:37:19 GMT", "version": "v2" } ]
2009-01-07
[ [ "Adhikari", "Rathin", "", "University of\n Calcutta and Jadavpur University" ], [ "Sil", "Arunansu", "", "University of\n Calcutta and Jadavpur University" ], [ "Raychaudhuri", "Amitava", "", "University of\n Calcutta and Jadavpur University" ] ]
We present a solution of the solar neutrino deficit using three flavors of neutrinos within the R-parity non-conserving supersymmetric model. In vacuum, mass and mixing is restricted to the nu(mu)-nu(tau) sector only, which we choose in consistency with the requirements of the atmospheric neutrino anomaly. The nu(e) is massless and unmixed. The flavor changing and flavor diagonal neutral currents present in the model and an energy-dependent resonance-induced nu(e)-nu(mu) mixing in the sun result in the new solution to the solar neutrino problem. The best fit to the solar neutrino rates and spectrum (1258-day SK data) requires a mass square difference of 10^{-5} eV^2 in vacuum between the two lightest neutrinos. This solution cannot accommodate a significant day-night effect for solar neutrinos.
hep-ph/0203051
Kingman Cheung
Ming-Yang Cheng (NTHU), Kingman Cheung (NCTS)
Zee model and Neutrinoless double beta decay
11 pages, references are added
null
null
NSC-NCTS-020304
hep-ph
null
The original Zee model can easily accommodate a bi-maximal mixing solution for the atmospheric and solar neutrino problems. From the most recent fit to the data we obtain a set of parameters for the Zee model. However, the recent claim on a positive signal observed in a neutrinoless double beta decay, which requires a nonzero $m_{ee}$, cannot be accounted for by the Zee model. Based on the observed neutrino mass-square differences and mixings, we derive a few general patterns for the neutrino mass matrix in the flavor basis, which can correctly describe the atmospheric, solar, and $0\nu\beta\beta$ data. Finally, we investigate a few possible extensions to the Zee model, which can give the required mass patterns.
[ { "created": "Tue, 5 Mar 2002 15:03:03 GMT", "version": "v1" }, { "created": "Tue, 2 Apr 2002 16:58:17 GMT", "version": "v2" } ]
2007-05-23
[ [ "Cheng", "Ming-Yang", "", "NTHU" ], [ "Cheung", "Kingman", "", "NCTS" ] ]
The original Zee model can easily accommodate a bi-maximal mixing solution for the atmospheric and solar neutrino problems. From the most recent fit to the data we obtain a set of parameters for the Zee model. However, the recent claim on a positive signal observed in a neutrinoless double beta decay, which requires a nonzero $m_{ee}$, cannot be accounted for by the Zee model. Based on the observed neutrino mass-square differences and mixings, we derive a few general patterns for the neutrino mass matrix in the flavor basis, which can correctly describe the atmospheric, solar, and $0\nu\beta\beta$ data. Finally, we investigate a few possible extensions to the Zee model, which can give the required mass patterns.
0906.2463
Schoeffel Laurent
Laurent Schoeffel (CEA Saclay, Irfu/SPP)
New developments in QCD analysis of inclusive diffraction at HERA
5 pages, 4 figures, proceedings of the XVII International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2009), 26-30 April 2009, Madrid
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A large collection of results for the diffractive dissociation of virtual photons, $\gamma^{\star}p \to Xp$, have been obtained with the H1 and ZEUS detectors at HERA. Different experimental techniques have been used, by requiring a large rapidity gap between $X$ and the outgoing proton, by analysing the mass distribution, $M_X$, of the hadronic final state, as well as by directly tagging the proton. A reasonable compatibility between those techniques and between H1 and ZEUS results have been observed. Some common fundamental features in the measurements are also present in all data sets. Diffractive PDFs can give a good account of those features. Ideas and new developments are discussed in these proceedings.
[ { "created": "Mon, 15 Jun 2009 09:25:47 GMT", "version": "v1" } ]
2009-06-16
[ [ "Schoeffel", "Laurent", "", "CEA Saclay, Irfu/SPP" ] ]
A large collection of results for the diffractive dissociation of virtual photons, $\gamma^{\star}p \to Xp$, have been obtained with the H1 and ZEUS detectors at HERA. Different experimental techniques have been used, by requiring a large rapidity gap between $X$ and the outgoing proton, by analysing the mass distribution, $M_X$, of the hadronic final state, as well as by directly tagging the proton. A reasonable compatibility between those techniques and between H1 and ZEUS results have been observed. Some common fundamental features in the measurements are also present in all data sets. Diffractive PDFs can give a good account of those features. Ideas and new developments are discussed in these proceedings.
hep-ph/9403229
null
Manuel Drees (Univ. of Wisconsin) and Rohini M. Godbole (Bombay Univ.)
Virtual Photon Strucutre Functions and the Parton Content of the Electron
16 pages and 3 figures (available from DREES@WSICPHEN as topdraw or PS files); LaTeX with equation.sty; MAD/PH/819, BU 94-02
Phys.Rev.D50:3124-3133,1994
10.1103/PhysRevD.50.3124
null
hep-ph
null
We point out that in processes involving the parton content of the photon the usual effective photon approximation should be modified. The reason is that the parton content of virtual photons is logarithmically suppressed compared to real photons. We describe this suppression using several simple, physically motivated ans\"atze. Although the parton content of the electron in general no longer factorizes into an electron flux function and a photon structure function, it can still be expressed as a single integral. Numerical examples are given for the \eplem\ collider TRISTAN as well as the $ep$ collider HERA.
[ { "created": "Fri, 4 Mar 1994 20:16:00 GMT", "version": "v1" } ]
2011-07-19
[ [ "Drees", "Manuel", "", "Univ. of Wisconsin" ], [ "Godbole", "Rohini M.", "", "Bombay Univ." ] ]
We point out that in processes involving the parton content of the photon the usual effective photon approximation should be modified. The reason is that the parton content of virtual photons is logarithmically suppressed compared to real photons. We describe this suppression using several simple, physically motivated ans\"atze. Although the parton content of the electron in general no longer factorizes into an electron flux function and a photon structure function, it can still be expressed as a single integral. Numerical examples are given for the \eplem\ collider TRISTAN as well as the $ep$ collider HERA.
2112.06426
Nijiati Yalikun
Nijiati Yalikun and Bing-Song Zou
Anticharmed strange pentaquarks from the one-boson-exchange model
15 pages, 3 figures and 6 tables
null
10.1103/PhysRevD.105.094026
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
Inspired by the LHCb's discovery of hidden-charm pentaquarks, the anticharmed strange pentaquarks $P_{\bar c s}$ in a favor of the hadronic molecule picture are investigated from the one-boson-exchange model. Similar to the hidden-charm pentaquarks, three molecular bound states, one with spin parity $J^P=1/2^-$ below the $\bar D\Sigma$ threshold and another two with $J^P=\{1/2^-,3/2^-\}$ below the $\bar D^*\Sigma$ threshold, are predicted at $3-3.2$ GeV mass region. The mass ordering of the later two states can be interchanged by different reductions of the $\delta(r)$ term. Furthermore, resonances associated with these three bound states are examined by considering $ D_s^-N-\bar D\Lambda-\bar D \Sigma-\bar D^*\Lambda-\bar D^*\Sigma$ coupled-channel dynamics, and decay widths of them are predicted. Our study indicates that the $ D_s^- p$ invariant mass spectrum in the $\bar B_s^0\to \bar n D_s^- p$ decay is an appropriate place to detect the $P_{\bar c s}$ pentaquarks.
[ { "created": "Mon, 13 Dec 2021 05:45:16 GMT", "version": "v1" }, { "created": "Fri, 17 Dec 2021 04:01:27 GMT", "version": "v2" }, { "created": "Fri, 18 Mar 2022 02:30:48 GMT", "version": "v3" }, { "created": "Mon, 23 May 2022 15:32:59 GMT", "version": "v4" } ]
2022-05-24
[ [ "Yalikun", "Nijiati", "" ], [ "Zou", "Bing-Song", "" ] ]
Inspired by the LHCb's discovery of hidden-charm pentaquarks, the anticharmed strange pentaquarks $P_{\bar c s}$ in a favor of the hadronic molecule picture are investigated from the one-boson-exchange model. Similar to the hidden-charm pentaquarks, three molecular bound states, one with spin parity $J^P=1/2^-$ below the $\bar D\Sigma$ threshold and another two with $J^P=\{1/2^-,3/2^-\}$ below the $\bar D^*\Sigma$ threshold, are predicted at $3-3.2$ GeV mass region. The mass ordering of the later two states can be interchanged by different reductions of the $\delta(r)$ term. Furthermore, resonances associated with these three bound states are examined by considering $ D_s^-N-\bar D\Lambda-\bar D \Sigma-\bar D^*\Lambda-\bar D^*\Sigma$ coupled-channel dynamics, and decay widths of them are predicted. Our study indicates that the $ D_s^- p$ invariant mass spectrum in the $\bar B_s^0\to \bar n D_s^- p$ decay is an appropriate place to detect the $P_{\bar c s}$ pentaquarks.
1008.1156
Berndt Muller
T. Kunihiro, B. M\"uller, A. Ohnishi, A. Sch\"afer, T. T. Takahashi, A Yamamoto
Chaotic behavior in classical Yang-Mills dynamics
null
Phys.Rev.D82:114015,2010
10.1103/PhysRevD.82.114015
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Understanding the underlying mechanisms causing rapid thermalization deduced for high-energy heavy ion collisions is still a challenge. To estimate the thermalization time, entropy growth for classical Yang-Mills theories is studied, based on the determination of Lyapunov exponents. Distinct regimes for short, medium and long sampling times are characterized by different properties of their spectrum of Lyapunov exponents. Clarifying the existence of these regimes and their implications for gauge-field dynamics is one of the results of this contribution. As a phenomenological application we conclude that for pure gauge theories with random initial conditions thermalization occurs within few fm/c, an estimate which can be reduced by the inclusion of fermions, specific initial conditions, etc.
[ { "created": "Fri, 6 Aug 2010 10:36:30 GMT", "version": "v1" } ]
2010-12-28
[ [ "Kunihiro", "T.", "" ], [ "Müller", "B.", "" ], [ "Ohnishi", "A.", "" ], [ "Schäfer", "A.", "" ], [ "Takahashi", "T. T.", "" ], [ "Yamamoto", "A", "" ] ]
Understanding the underlying mechanisms causing rapid thermalization deduced for high-energy heavy ion collisions is still a challenge. To estimate the thermalization time, entropy growth for classical Yang-Mills theories is studied, based on the determination of Lyapunov exponents. Distinct regimes for short, medium and long sampling times are characterized by different properties of their spectrum of Lyapunov exponents. Clarifying the existence of these regimes and their implications for gauge-field dynamics is one of the results of this contribution. As a phenomenological application we conclude that for pure gauge theories with random initial conditions thermalization occurs within few fm/c, an estimate which can be reduced by the inclusion of fermions, specific initial conditions, etc.
hep-ph/9306314
null
Stephen P. Martin and Pierre Ramond
Sparticle Spectrum Constraints
25 pages. NUB-3067-93TH, UFIFT-HEP-93-16, SSCL-Preprint-439, June 1993
Phys.Rev.D48:5365-5375,1993
10.1103/PhysRevD.48.5365
null
hep-ph
null
The supersymmetric standard model with supergravity-inspired soft breaking terms predicts a rich pectrum of sparticles to be discovered at the SSC, LHC and NLC. Because there are more supersymmetric particles than unknown parameters, one can write down sum rules relating their masses. We discuss the pectrum of sparticles from this point of view. Some of the sum rules do not depend on the input parameters and can be used to test the consistency of the model, while others are useful in determining the input parameters of the theory. If supersymmetry is discovered but the sum rules turn out to be violated, it will be evidence of new physics beyond the minimal supersymmetric standard model with universal soft supersymmetry-breaking terms.
[ { "created": "Wed, 23 Jun 1993 01:17:00 GMT", "version": "v1" } ]
2011-03-04
[ [ "Martin", "Stephen P.", "" ], [ "Ramond", "Pierre", "" ] ]
The supersymmetric standard model with supergravity-inspired soft breaking terms predicts a rich pectrum of sparticles to be discovered at the SSC, LHC and NLC. Because there are more supersymmetric particles than unknown parameters, one can write down sum rules relating their masses. We discuss the pectrum of sparticles from this point of view. Some of the sum rules do not depend on the input parameters and can be used to test the consistency of the model, while others are useful in determining the input parameters of the theory. If supersymmetry is discovered but the sum rules turn out to be violated, it will be evidence of new physics beyond the minimal supersymmetric standard model with universal soft supersymmetry-breaking terms.
hep-ph/0102149
Joannis Papavassiliou
Joannis Papavassiliou
Breit-Wigner formalism for non-Abelian theories
10 pages, plain Latex, 4 Figures in a separate ps. file; based on talk presented at ``50 Years of Electroweak Physics: A symposium in honor of Professor Alberto Sirlin's 70th Birthday'', New York University, New York, October 27-28, 2000
J.Phys.G29:153-160,2003
10.1088/0954-3899/29/1/316
null
hep-ph
null
The consistent description of resonant transition amplitudes within the framework of perturbative field theories necessitates the definition and resummation of off-shell Green's functions, which must respect several crucial physical requirements. In particular, the generalization of the usual Breit-Wigner formalism in a non-Abelian context constitutes a highly non-trivial problem, related to the fact that the conventionally defined Green's functions are unphysical. We briefly review the main field-theoretical difficulties arising when attempting to use such Green's functions outside the confines of a fixed order perturbative calculation, and explain how this task has been successfully accomplished in the framework of the pinch technique.
[ { "created": "Tue, 13 Feb 2001 12:18:37 GMT", "version": "v1" } ]
2008-11-26
[ [ "Papavassiliou", "Joannis", "" ] ]
The consistent description of resonant transition amplitudes within the framework of perturbative field theories necessitates the definition and resummation of off-shell Green's functions, which must respect several crucial physical requirements. In particular, the generalization of the usual Breit-Wigner formalism in a non-Abelian context constitutes a highly non-trivial problem, related to the fact that the conventionally defined Green's functions are unphysical. We briefly review the main field-theoretical difficulties arising when attempting to use such Green's functions outside the confines of a fixed order perturbative calculation, and explain how this task has been successfully accomplished in the framework of the pinch technique.
hep-ph/9903213
Joan Sola
J. A. Coarasa, Jaume Guasch, Joan Sola
Gamma(H+ -> t \bar{b}) in the MSSM: a handle for SUSY charged Higgs at the Tevatron and the LHC
15 pages, LaTeX2e, 4 multicomponent figures included. Talk presented at the IVth International Symposium on Radiative Corrections (RADCOR 98), Barcelona, September 8-12, 1998
null
null
UAB-FT-452
hep-ph
null
We compute Gamma(H+ -> t \bar{b}) at one-loop in the MSSM and show how future data at the Tevatron and/or at the LHC could be used to unravel the potential SUSY nature of the charged Higgs.
[ { "created": "Mon, 1 Mar 1999 16:25:53 GMT", "version": "v1" } ]
2007-05-23
[ [ "Coarasa", "J. A.", "" ], [ "Guasch", "Jaume", "" ], [ "Sola", "Joan", "" ] ]
We compute Gamma(H+ -> t \bar{b}) at one-loop in the MSSM and show how future data at the Tevatron and/or at the LHC could be used to unravel the potential SUSY nature of the charged Higgs.
2402.18906
Hrishi Bora
Hrishi Bora, Ng. K. Francis, Bikash Thapa and Shawan Kumar Jha
Neutrino Mixing and Resonant Leptogenesis in Inverse Seesaw and {\Delta}(54) Flavor Symmetry
13 pages, 5 figures, 2 tables
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The current work involves augmenting the $\Delta(54)$ discrete flavor model by incorporating two Standard Model Higgs particles into the Inverse Seesaw mechanism. We introduced Weyl fermions and Vector like fermions, which are gauge singlets in the Standard Model and produces Majorana mass terms in our lagrangian. The resulting mass matrix deviates from the tribimaximal neutrino mixing pattern producing a non-zero reactor angle ($\theta_{13}$) . We have determined the effective Majorana neutrino mass, which is the parameter of relevance in neutrinoless double beta decay investigations, using the model's limited six-dimensional parameter space. We additionally investigate the possibility of baryogenesis in the proposed framework via resonant leptogenesis. We have the non-zero value for resonantly enhanced CP asymmetry originating from the decay of right-handed neutrinos at the TeV scale, accounting for flavor effects. The evolution of lepton asymmetry is systematically analyzed by numerically solving a set of Boltzmann equations, leading to the determination of the baryon asymmetry with a magnitude of $ \lvert \eta_B \rvert \approx 6 \times 10^{-10}$. This outcome is achieved by selecting specific values for the right-handed neutrino mass $M_1 = 10$ TeV and mass splitting, $d \approx 10^{-8}$.
[ { "created": "Thu, 29 Feb 2024 07:02:23 GMT", "version": "v1" } ]
2024-03-01
[ [ "Bora", "Hrishi", "" ], [ "Francis", "Ng. K.", "" ], [ "Thapa", "Bikash", "" ], [ "Jha", "Shawan Kumar", "" ] ]
The current work involves augmenting the $\Delta(54)$ discrete flavor model by incorporating two Standard Model Higgs particles into the Inverse Seesaw mechanism. We introduced Weyl fermions and Vector like fermions, which are gauge singlets in the Standard Model and produces Majorana mass terms in our lagrangian. The resulting mass matrix deviates from the tribimaximal neutrino mixing pattern producing a non-zero reactor angle ($\theta_{13}$) . We have determined the effective Majorana neutrino mass, which is the parameter of relevance in neutrinoless double beta decay investigations, using the model's limited six-dimensional parameter space. We additionally investigate the possibility of baryogenesis in the proposed framework via resonant leptogenesis. We have the non-zero value for resonantly enhanced CP asymmetry originating from the decay of right-handed neutrinos at the TeV scale, accounting for flavor effects. The evolution of lepton asymmetry is systematically analyzed by numerically solving a set of Boltzmann equations, leading to the determination of the baryon asymmetry with a magnitude of $ \lvert \eta_B \rvert \approx 6 \times 10^{-10}$. This outcome is achieved by selecting specific values for the right-handed neutrino mass $M_1 = 10$ TeV and mass splitting, $d \approx 10^{-8}$.
1005.3330
Nikolaos Kidonakis
Nikolaos Kidonakis
Single top quark production cross section at hadron colliders
5 pages, 8 figures; to appear in proceedings of DIS2010
PoS DIS2010:196,2010
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I present results for the theoretical cross section of single top quark production in the s channel and also via associated production with a W boson or a charged Higgs. The calculations include higher-order corrections at NNLL accuracy. Detailed numerical results are provided for Tevatron and LHC energies.
[ { "created": "Tue, 18 May 2010 21:09:46 GMT", "version": "v1" } ]
2010-11-19
[ [ "Kidonakis", "Nikolaos", "" ] ]
I present results for the theoretical cross section of single top quark production in the s channel and also via associated production with a W boson or a charged Higgs. The calculations include higher-order corrections at NNLL accuracy. Detailed numerical results are provided for Tevatron and LHC energies.
hep-ph/9512224
Kurt Riesselmann
Loyal Durand and Kurt Riesselmann
The Goldstone boson equivalence theorem with fermions
32 pages, uses LaTeX2e, epsf and rotate, 7 figures included as separate uuencoded packed file. A complete PostScript version can also be obtained from http://www.physik.tu-muenchen.de/tumphy/d/T30d/PAPERS/TUM-HEP-227-95.ps.gz
Phys.Rev. D55 (1997) 1533-1547
10.1103/PhysRevD.55.1533
TUM-HEP-227/95
hep-ph
null
The calculation of the leading electroweak corrections to physical transition matrix elements in powers of $M_H^2/v^2$ can be greatly simplified in the limit $M_H^2\gg M_W^2,\, M_Z^2$ through the use of the Goldstone boson equivalence theorem. This theorem allows the vector bosons $W^\pm$ and $Z$ to be replaced by the associated scalar Goldstone bosons $w^\pm$, $z$ which appear in the symmetry breaking sector of the Standard Model in the limit of vanishing gauge couplings. In the present paper, we extend the equivalence theorem systematically to include the Yukawa interactions between the fermions and the Higgs and Goldstone bosons of the Standard Model. The corresponding Lagrangian ${\cal L}_{EQT}$ is given, and is formally renormalized to all orders. The renormalization conditions are formulated both to make connection with physical observables and to satisfy the requirements underlying the equivalence theorem. As an application of this framework, we calculate the dominant radiative corrections to fermionic Higgs decays at one loop including the virtual effects of a heavy top quark. We apply the result to the decays $H\rightarrow t\bar{t}$ and $H\rightarrow b\bar{b}$, and find that the equivalence theorem results including fermions are quite accurate numerically for Higgs-boson masses $M_H> 400\,(350)$ GeV, respectively, even for $m_t=175$ GeV.
[ { "created": "Mon, 4 Dec 1995 18:00:37 GMT", "version": "v1" } ]
2009-10-28
[ [ "Durand", "Loyal", "" ], [ "Riesselmann", "Kurt", "" ] ]
The calculation of the leading electroweak corrections to physical transition matrix elements in powers of $M_H^2/v^2$ can be greatly simplified in the limit $M_H^2\gg M_W^2,\, M_Z^2$ through the use of the Goldstone boson equivalence theorem. This theorem allows the vector bosons $W^\pm$ and $Z$ to be replaced by the associated scalar Goldstone bosons $w^\pm$, $z$ which appear in the symmetry breaking sector of the Standard Model in the limit of vanishing gauge couplings. In the present paper, we extend the equivalence theorem systematically to include the Yukawa interactions between the fermions and the Higgs and Goldstone bosons of the Standard Model. The corresponding Lagrangian ${\cal L}_{EQT}$ is given, and is formally renormalized to all orders. The renormalization conditions are formulated both to make connection with physical observables and to satisfy the requirements underlying the equivalence theorem. As an application of this framework, we calculate the dominant radiative corrections to fermionic Higgs decays at one loop including the virtual effects of a heavy top quark. We apply the result to the decays $H\rightarrow t\bar{t}$ and $H\rightarrow b\bar{b}$, and find that the equivalence theorem results including fermions are quite accurate numerically for Higgs-boson masses $M_H> 400\,(350)$ GeV, respectively, even for $m_t=175$ GeV.
1109.3859
Michelangelo Mangano
S. S. AbdusSalam, B. C. Allanach, H. K. Dreiner, J. Ellis, U. Ellwanger, J. Gunion, S. Heinemeyer, M. Kraemer, M. L. Mangano, K. A. Olive, S. Rogerson, L. Roszkowski, M. Schlaffer, G. Weiglein
Benchmark Models, Planes, Lines and Points for Future SUSY Searches at the LHC
30 pages, 4 figures. v2 fixes few typos and bibliography. v3 updates Fig.1 and bibliography
null
10.1140/epjc/s10052-011-1835-7
CERN-PH-TH/2011-224; DAMTP-2011-69; DESY 11-90; FTPI-MINN-11/22; KCL-PH-TH/2011-30; LCTS/2011-15; LPT Orsay 11-76; TTK-11-41; UMN-TH-3012/11
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We define benchmark models for SUSY searches at the LHC, including the CMSSM, NUHM, mGMSB, mAMSB, MM-AMSB and p19MSSM, as well as models with R-parity violation and the NMSSM. Within the parameter spaces of these models, we propose benchmark subspaces, including planes, lines and points along them. The planes may be useful for presenting results of the experimental searches in different SUSY scenarios, while the specific benchmark points may serve for more detailed detector performance tests and comparisons. We also describe algorithms for defining suitable benchmark points along the proposed lines in the parameter spaces, and we define a few benchmark points motivated by recent fits to existing experimental data.
[ { "created": "Sun, 18 Sep 2011 10:49:10 GMT", "version": "v1" }, { "created": "Mon, 7 Nov 2011 15:30:17 GMT", "version": "v2" }, { "created": "Tue, 6 Mar 2012 15:07:10 GMT", "version": "v3" } ]
2015-05-30
[ [ "AbdusSalam", "S. S.", "" ], [ "Allanach", "B. C.", "" ], [ "Dreiner", "H. K.", "" ], [ "Ellis", "J.", "" ], [ "Ellwanger", "U.", "" ], [ "Gunion", "J.", "" ], [ "Heinemeyer", "S.", "" ], [ "Kraemer", "M.", "" ], [ "Mangano", "M. L.", "" ], [ "Olive", "K. A.", "" ], [ "Rogerson", "S.", "" ], [ "Roszkowski", "L.", "" ], [ "Schlaffer", "M.", "" ], [ "Weiglein", "G.", "" ] ]
We define benchmark models for SUSY searches at the LHC, including the CMSSM, NUHM, mGMSB, mAMSB, MM-AMSB and p19MSSM, as well as models with R-parity violation and the NMSSM. Within the parameter spaces of these models, we propose benchmark subspaces, including planes, lines and points along them. The planes may be useful for presenting results of the experimental searches in different SUSY scenarios, while the specific benchmark points may serve for more detailed detector performance tests and comparisons. We also describe algorithms for defining suitable benchmark points along the proposed lines in the parameter spaces, and we define a few benchmark points motivated by recent fits to existing experimental data.
hep-ph/9802446
Alessandro Strumia
Marco Picariello and Alessandro Strumia
Next-to-leading order corrections to gauge-mediated gaugino masses
12 pages
Nucl.Phys.B529:81-95,1998
10.1016/S0550-3213(98)00383-6
IFUP-TH 63/97
hep-ph
null
We compute the next-to-leading order corrections to the gaugino masses $M_i$ in gauge-mediated models for generic values of the messenger masses M and discuss the predictions of unified messenger models. If M<100 TeV there can be up to 10% corrections to the leading order relations $M_i\propto \alpha_i$. If the messengers are heavier there are only few % corrections. We also study the messenger corrections to gauge coupling unification: as a result of cancellations dictated by supersymmetry, the predicted value of the strong coupling constant is typically only negligibly increased.
[ { "created": "Fri, 27 Feb 1998 17:19:13 GMT", "version": "v1" } ]
2009-10-09
[ [ "Picariello", "Marco", "" ], [ "Strumia", "Alessandro", "" ] ]
We compute the next-to-leading order corrections to the gaugino masses $M_i$ in gauge-mediated models for generic values of the messenger masses M and discuss the predictions of unified messenger models. If M<100 TeV there can be up to 10% corrections to the leading order relations $M_i\propto \alpha_i$. If the messengers are heavier there are only few % corrections. We also study the messenger corrections to gauge coupling unification: as a result of cancellations dictated by supersymmetry, the predicted value of the strong coupling constant is typically only negligibly increased.
hep-ph/0411326
Pedro Fernando Simoes Costa
Pedro Costa, M. C. Ruivo, C. A. de Sousa, Yu. L. Kalinovsky
Is the U$_A$(1) symmetry restored at finite temperature or density?
3 pages, 1 figure. Talk given at 6th Conference on Quark Confinement and the Hadron Spectrum, Villasimius, Sardinia, Italy, 21-25 Sep 2004
AIP Conf.Proc. 756 (2005) 351
10.1063/1.1920990
null
hep-ph
null
We investigate the full U(3)$\otimes$U(3) chiral symmetry restoration, at finite temperature and density, on the basis of the three flavor Nambu-Jona-Lasinio model with the anomaly term given by the 't Hooft interaction. We implement a temperature (density) dependence of the anomaly coefficient motivated by lattice results for the topological susceptibility. The results suggest that the axial part of the symmetry is restored before the possible restoration of the full U(3)$\otimes$U(3) chiral symmetry can occur.
[ { "created": "Wed, 24 Nov 2004 16:35:34 GMT", "version": "v1" } ]
2007-05-23
[ [ "Costa", "Pedro", "" ], [ "Ruivo", "M. C.", "" ], [ "de Sousa", "C. A.", "" ], [ "Kalinovsky", "Yu. L.", "" ] ]
We investigate the full U(3)$\otimes$U(3) chiral symmetry restoration, at finite temperature and density, on the basis of the three flavor Nambu-Jona-Lasinio model with the anomaly term given by the 't Hooft interaction. We implement a temperature (density) dependence of the anomaly coefficient motivated by lattice results for the topological susceptibility. The results suggest that the axial part of the symmetry is restored before the possible restoration of the full U(3)$\otimes$U(3) chiral symmetry can occur.
1007.0846
Alexey Novoselov
Alexey Novoselov
A study of charm hadron production in e^+e^- annihilation
21 pages, 15 figures
null
10.1134/S1063778810100091
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The processes of D^{(*)}-mesons and \Lambda_c-baryons production in e^+e^--annihilation at 10.58 GeV and 91.18 GeV energies are concerned. At the 10.58 GeV energy the production of charmed particles via the B-mesons decays is also concerned. Scaling violation of the fragmentation functions is calculated at the NLL-accuracy. Nonperturbative fragmentation functions are retrieved from the experimental data of B-factories and are approximated by simple analytic expressions. It is proved, that the difference between nonperturbative fragmentation functions of mesons and baryons can be easily explained by quark counting.
[ { "created": "Tue, 6 Jul 2010 09:58:32 GMT", "version": "v1" }, { "created": "Wed, 7 Jul 2010 07:14:45 GMT", "version": "v2" } ]
2010-12-30
[ [ "Novoselov", "Alexey", "" ] ]
The processes of D^{(*)}-mesons and \Lambda_c-baryons production in e^+e^--annihilation at 10.58 GeV and 91.18 GeV energies are concerned. At the 10.58 GeV energy the production of charmed particles via the B-mesons decays is also concerned. Scaling violation of the fragmentation functions is calculated at the NLL-accuracy. Nonperturbative fragmentation functions are retrieved from the experimental data of B-factories and are approximated by simple analytic expressions. It is proved, that the difference between nonperturbative fragmentation functions of mesons and baryons can be easily explained by quark counting.
hep-ph/9809211
Chris Michael
Chris Michael
Adiabatic surfaces from the lattice: excited gluonic potentials
19 pages, latex using worldsci.sty, 10 figures, talk presented at the CONFINEMENT III conference in Newport News, Virginia, USA
null
null
LTH 435
hep-ph hep-lat
null
I describe the results from lattice studies of probing the vacuum with static colour sources. Topics include (i) Twang the flux tube: string models and hybrid mesons. (ii) Charge up the flux tube: adjoint and sextet sources. (iii) Several sources: how does the colour flux get arranged?
[ { "created": "Tue, 1 Sep 1998 11:35:15 GMT", "version": "v1" } ]
2016-09-06
[ [ "Michael", "Chris", "" ] ]
I describe the results from lattice studies of probing the vacuum with static colour sources. Topics include (i) Twang the flux tube: string models and hybrid mesons. (ii) Charge up the flux tube: adjoint and sextet sources. (iii) Several sources: how does the colour flux get arranged?
2211.17061
Su-Zhi Wu
Su-Zhi Wu, Pei Wu and You-Wei Li
Production of the triply heavy $\Omega_{ccc}$ and $\Omega_{bbb}$ baryons at $e^+e^-$ colliders
null
PhysRevD.107.116022,2023
10.1103/PhysRevD.107.116022
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Non-relativistic quantum chromodynamics (NRQCD) factorization formulism is an important approach to investigate the production of the heavy quarkonium. In this paper, we study the production of the $\Omega_{ccc}$ and $\Omega_{bbb}$ at the $e^+e^-$ collider, using the NRQCD factorization formulism. We calculate the total and differential cross sections exactly of the processes, $e^+e^-\rightarrow \gamma^*/Z^*\rightarrow \Omega_{ccc}\bar{c}\bar{c}\bar{c}$ and $e^+e^-\rightarrow \gamma^*/Z^*\rightarrow \Omega_{bbb}\bar{b}\bar{b}\bar{b}$, in the leading order at the $e^+e^-$ colliders with different energies. The results show that it is hard to observe them at the $e^+e^-$ collider directly.
[ { "created": "Wed, 30 Nov 2022 15:11:14 GMT", "version": "v1" }, { "created": "Sun, 29 Jan 2023 09:28:48 GMT", "version": "v2" }, { "created": "Tue, 31 Jan 2023 16:29:53 GMT", "version": "v3" }, { "created": "Thu, 4 May 2023 15:47:21 GMT", "version": "v4" }, { "created": "Wed, 28 Jun 2023 08:17:47 GMT", "version": "v5" } ]
2023-06-29
[ [ "Wu", "Su-Zhi", "" ], [ "Wu", "Pei", "" ], [ "Li", "You-Wei", "" ] ]
Non-relativistic quantum chromodynamics (NRQCD) factorization formulism is an important approach to investigate the production of the heavy quarkonium. In this paper, we study the production of the $\Omega_{ccc}$ and $\Omega_{bbb}$ at the $e^+e^-$ collider, using the NRQCD factorization formulism. We calculate the total and differential cross sections exactly of the processes, $e^+e^-\rightarrow \gamma^*/Z^*\rightarrow \Omega_{ccc}\bar{c}\bar{c}\bar{c}$ and $e^+e^-\rightarrow \gamma^*/Z^*\rightarrow \Omega_{bbb}\bar{b}\bar{b}\bar{b}$, in the leading order at the $e^+e^-$ colliders with different energies. The results show that it is hard to observe them at the $e^+e^-$ collider directly.
1808.09550
Volodymyr Vovchenko
Leonid Frankfurt, Mark Strikman, Alexei Larionov, Andreas Lehrach, Rudolf Maier, Hendrik van Hees, Christian Spieles, Volodymyr Vovchenko, Horst Stoecker
Novel physics opportunities at the HESR-Collider with PANDA at FAIR
29 pages, 5 figures. To appear in the memorial volume for Walter Greiner of the Springer-Nature FIAS Interdisciplinary Science series
null
null
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Exciting new scientific opportunities are presented for the PANDA detector at the High Energy Storage Ring in the redefined $\bar{\text{p}} \text{p}(A)$ collider mode, HESR-C, at the Facility for Antiproton and Ion Research (FAIR) in Europe. The high luminosity, $L \sim 10^{31}$ cm$^{-2}$ s$^{-1}$, and a wide range of intermediate and high energies, $\sqrt{s_{\text{NN}}}$ up to 30 GeV for $\bar{\text{p}} \text{p}(A)$ collisions will allow to explore a wide range of exciting topics in QCD, including the study of the production of excited open charm and bottom states, nuclear bound states containing heavy (anti)quarks, the interplay of hard and soft physics in the dilepton production, and the exploration of the regime where gluons -- but not quarks -- experience strong interaction.
[ { "created": "Tue, 28 Aug 2018 21:25:50 GMT", "version": "v1" } ]
2019-08-07
[ [ "Frankfurt", "Leonid", "" ], [ "Strikman", "Mark", "" ], [ "Larionov", "Alexei", "" ], [ "Lehrach", "Andreas", "" ], [ "Maier", "Rudolf", "" ], [ "van Hees", "Hendrik", "" ], [ "Spieles", "Christian", "" ], [ "Vovchenko", "Volodymyr", "" ], [ "Stoecker", "Horst", "" ] ]
Exciting new scientific opportunities are presented for the PANDA detector at the High Energy Storage Ring in the redefined $\bar{\text{p}} \text{p}(A)$ collider mode, HESR-C, at the Facility for Antiproton and Ion Research (FAIR) in Europe. The high luminosity, $L \sim 10^{31}$ cm$^{-2}$ s$^{-1}$, and a wide range of intermediate and high energies, $\sqrt{s_{\text{NN}}}$ up to 30 GeV for $\bar{\text{p}} \text{p}(A)$ collisions will allow to explore a wide range of exciting topics in QCD, including the study of the production of excited open charm and bottom states, nuclear bound states containing heavy (anti)quarks, the interplay of hard and soft physics in the dilepton production, and the exploration of the regime where gluons -- but not quarks -- experience strong interaction.
1709.06352
Raghunath Sahoo
Swatantra Kumar Tiwari, Sushanta Tripathy, Raghunath Sahoo, and Nilotpal Kakati
Dissipative Properties and Isothermal Compressibility of Hot and Dense Hadron Gas using Non-extensive Statistics
Same as published version
Eur. Phys. J. C 78 (2018) 938
10.1140/epjc/s10052-018-6411-y
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We evaluate the transport properties such as shear viscosity ($\eta$), bulk viscosity ($\zeta$) and their ratios over entropy density ($s$) for hadronic matter using relativistic non-extensive Boltzmann transport equation (NBTE) in relaxation time approximation (RTA). In NBTE, we argue that the system far from equilibrium may not reach to an equilibrium described by extensive (Boltzmann-Gibbs (BG)) statistics but to a $q$-equilibrium defined by Tsallis non-extensive statistics after subsequent evolution, where $q$ denotes the degree of non-extensivity. We observe that $\eta/s$ and $\zeta/s$ decrease rapidly with temperature ($T$) for various $q$-values. As $q$ increases, the magnitudes of $\eta/s$ and $\zeta/s$ decrease with $T$. We also show the upper mass cutoff dependence of these ratios for a particular $q$ and find that they decrease with the increase in mass cutoff of hadrons. Further, we present the first estimation of isothermal compressibility ($\kappa_T$) using non-extensive Tsallis statistics at finite baryon chemical potential ($\mu_B$). It is observed that, $\kappa_T$ changes significantly with the degree of non-extensivity. We also study the squared speed of sound ($c_{s}^{2}$) as a function of temperature at finite baryon chemical potential for various $q$ and upper mass cutoffs. It is noticed that there is a strong impact of $q$ and mass cutoff on the behaviour of $c_{s}^{2}$.
[ { "created": "Tue, 19 Sep 2017 11:24:11 GMT", "version": "v1" }, { "created": "Tue, 20 Nov 2018 09:21:13 GMT", "version": "v2" } ]
2018-11-21
[ [ "Tiwari", "Swatantra Kumar", "" ], [ "Tripathy", "Sushanta", "" ], [ "Sahoo", "Raghunath", "" ], [ "Kakati", "Nilotpal", "" ] ]
We evaluate the transport properties such as shear viscosity ($\eta$), bulk viscosity ($\zeta$) and their ratios over entropy density ($s$) for hadronic matter using relativistic non-extensive Boltzmann transport equation (NBTE) in relaxation time approximation (RTA). In NBTE, we argue that the system far from equilibrium may not reach to an equilibrium described by extensive (Boltzmann-Gibbs (BG)) statistics but to a $q$-equilibrium defined by Tsallis non-extensive statistics after subsequent evolution, where $q$ denotes the degree of non-extensivity. We observe that $\eta/s$ and $\zeta/s$ decrease rapidly with temperature ($T$) for various $q$-values. As $q$ increases, the magnitudes of $\eta/s$ and $\zeta/s$ decrease with $T$. We also show the upper mass cutoff dependence of these ratios for a particular $q$ and find that they decrease with the increase in mass cutoff of hadrons. Further, we present the first estimation of isothermal compressibility ($\kappa_T$) using non-extensive Tsallis statistics at finite baryon chemical potential ($\mu_B$). It is observed that, $\kappa_T$ changes significantly with the degree of non-extensivity. We also study the squared speed of sound ($c_{s}^{2}$) as a function of temperature at finite baryon chemical potential for various $q$ and upper mass cutoffs. It is noticed that there is a strong impact of $q$ and mass cutoff on the behaviour of $c_{s}^{2}$.
hep-ph/0602194
Santi Peris
Oscar Cata (UAB-IFAE), Maarten Golterman (UAB-IFAE and SFSU) and Santi Peris (UAB-IFAE)
The operator product expansion does not imply parity doubling of hadrons
9 pages, LateX
Phys.Rev.D74:016001,2006
10.1103/PhysRevD.74.016001
null
hep-ph hep-lat nucl-th
null
We examine whether the fact that QCD is chirally invariant at short distances necessarily leads to the prediction that hadrons form approximate parity doublets, as has been recently put forward by Glozman and collaborators. We show that this is not the case, and we exhibit some of the pitfalls of trying to link the operator product expansion to the hadron spectrum. We illustrate our arguments within a model for scalar and pseudo-scalar mesons used recently by Shifman to argue for parity doubling. We find that, whatever the experimental situation may be, there is no theoretical basis for parity doubling based on the use of the operator product expansion.
[ { "created": "Tue, 21 Feb 2006 15:36:16 GMT", "version": "v1" } ]
2008-11-26
[ [ "Cata", "Oscar", "", "UAB-IFAE" ], [ "Golterman", "Maarten", "", "UAB-IFAE and SFSU" ], [ "Peris", "Santi", "", "UAB-IFAE" ] ]
We examine whether the fact that QCD is chirally invariant at short distances necessarily leads to the prediction that hadrons form approximate parity doublets, as has been recently put forward by Glozman and collaborators. We show that this is not the case, and we exhibit some of the pitfalls of trying to link the operator product expansion to the hadron spectrum. We illustrate our arguments within a model for scalar and pseudo-scalar mesons used recently by Shifman to argue for parity doubling. We find that, whatever the experimental situation may be, there is no theoretical basis for parity doubling based on the use of the operator product expansion.
hep-ph/9709297
John Terning
Bogdan A. Dobrescu and John Terning
Negative contributions to S in an effective field theory
12 pages, 1 fig., LaTeX, typos corrected, improved referencing
Phys.Lett. B416 (1998) 129-136
10.1016/S0370-2693(97)01304-X
BUHEP-97-27, UCB-PTH-97/44
hep-ph
null
We show that an effective field theory that includes non-standard couplings between the electroweak gauge bosons and the top and bottom quarks may yield negative contributions to both the S and T oblique radiative electroweak parameters. We find that that such an effective field theory provides a better fit to data than the standard model (the chi-squared per degree of freedom is half as large). We examine in some detail an illustrative model where the exchange of heavy scalars produces the correct type of non-standard couplings.
[ { "created": "Tue, 9 Sep 1997 23:51:01 GMT", "version": "v1" }, { "created": "Fri, 12 Sep 1997 23:25:24 GMT", "version": "v2" }, { "created": "Fri, 19 Sep 1997 20:17:00 GMT", "version": "v3" } ]
2009-10-30
[ [ "Dobrescu", "Bogdan A.", "" ], [ "Terning", "John", "" ] ]
We show that an effective field theory that includes non-standard couplings between the electroweak gauge bosons and the top and bottom quarks may yield negative contributions to both the S and T oblique radiative electroweak parameters. We find that that such an effective field theory provides a better fit to data than the standard model (the chi-squared per degree of freedom is half as large). We examine in some detail an illustrative model where the exchange of heavy scalars produces the correct type of non-standard couplings.
1607.05571
Mathieu Pellen
Ansgar Denner and Mathieu Pellen
NLO electroweak corrections to off-shell top-antitop production with leptonic decays at the LHC
33 pages,23 eps-figures. Matches the published version. Typo fixed in equations (2.18) and (2.19)
JHEP 1608 (2016) 155
10.1007/JHEP08(2016)155
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For the first time the next-to-leading-order electroweak corrections to the full off-shell production of two top quarks that decay leptonically are presented. This calculation includes all off-shell, non-resonant, and interference effects for the 6-particle phase space. While the electroweak corrections are below one per cent for the integrated cross section, they reach up to 15% in the high-transverse-momentum region of distributions. To support the results of the complete one-loop calculation, we have in addition evaluated the electroweak corrections in two different pole approximations, one requiring two on-shell top quarks and one featuring two on-shell W bosons. While the former deviates by up to 10% from the full calculation for certain distributions, the latter provides a very good description for most observables. The increased centre-of-mass energy of the LHC makes the inclusion of electroweak corrections extremely relevant as they are particularly large in the Sudakov regime where new physics is expected to be probed.
[ { "created": "Tue, 19 Jul 2016 13:43:25 GMT", "version": "v1" }, { "created": "Fri, 2 Sep 2016 10:32:30 GMT", "version": "v2" }, { "created": "Tue, 14 Feb 2017 14:24:47 GMT", "version": "v3" } ]
2017-02-15
[ [ "Denner", "Ansgar", "" ], [ "Pellen", "Mathieu", "" ] ]
For the first time the next-to-leading-order electroweak corrections to the full off-shell production of two top quarks that decay leptonically are presented. This calculation includes all off-shell, non-resonant, and interference effects for the 6-particle phase space. While the electroweak corrections are below one per cent for the integrated cross section, they reach up to 15% in the high-transverse-momentum region of distributions. To support the results of the complete one-loop calculation, we have in addition evaluated the electroweak corrections in two different pole approximations, one requiring two on-shell top quarks and one featuring two on-shell W bosons. While the former deviates by up to 10% from the full calculation for certain distributions, the latter provides a very good description for most observables. The increased centre-of-mass energy of the LHC makes the inclusion of electroweak corrections extremely relevant as they are particularly large in the Sudakov regime where new physics is expected to be probed.
1302.6889
Gilberto Ramalho
G. Ramalho and K. Tsushima
Octet to decuplet electromagnetic transition in a relativistic quark model
Published in PRD. Version accepted for publication. 18 pages, 7 figures and 11 tables
Phys. Rev. D 87, 093011 (2013)
10.1103/PhysRevD.87.093011
ADP-13-07/T827
hep-ph hep-ex hep-lat nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the octet to decuplet baryon electromagnetic transitions using the covariant spectator quark model, and predict the transition magnetic dipole form factors for those involving the strange baryons. Utilizing SU(3) symmetry, the valence quark contributions are supplemented by the pion cloud dressing based on the one estimated in the $\gamma^\ast N \to \Delta$ reaction. Although the valence quark contributions are dominant in general, the pion cloud effects turn out to be very important to describe the experimental data. We also show that, other mesons besides the pion in particular the kaon, may be relevant for some reactions such as $\gamma^\ast \Sigma^+ \to \Sigma^{*+}$, based on our analysis for the radiative decay widths of the strange decuplet baryons.
[ { "created": "Wed, 27 Feb 2013 15:58:23 GMT", "version": "v1" }, { "created": "Thu, 23 May 2013 18:02:06 GMT", "version": "v2" } ]
2013-06-06
[ [ "Ramalho", "G.", "" ], [ "Tsushima", "K.", "" ] ]
We study the octet to decuplet baryon electromagnetic transitions using the covariant spectator quark model, and predict the transition magnetic dipole form factors for those involving the strange baryons. Utilizing SU(3) symmetry, the valence quark contributions are supplemented by the pion cloud dressing based on the one estimated in the $\gamma^\ast N \to \Delta$ reaction. Although the valence quark contributions are dominant in general, the pion cloud effects turn out to be very important to describe the experimental data. We also show that, other mesons besides the pion in particular the kaon, may be relevant for some reactions such as $\gamma^\ast \Sigma^+ \to \Sigma^{*+}$, based on our analysis for the radiative decay widths of the strange decuplet baryons.
2302.06794
J.K. Chen
Jiao-Kai Chen
Regge trajectory relations for the universal description of the heavy-light systems: diquarks, mesons, baryons and tetraquarks
11 pages, 6 figures and 5 tables. V4
Eur. Phys. J. C (2024) 84:356
10.1140/epjc/s10052-024-12706-9
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Two newly proposed Regge trajectory relations are employed to analyze the heavy-light systems. One of the relations is $M=m_1+m_2+C'+\beta_x\sqrt{x+c_{0x}}$, $(x=l,\,n_r)$. Another reads $M=m_1+C'+\sqrt{\beta_x^2(x+c_{0x})+\frac{4}{3}\sqrt{{\pi}{\beta_x}}m^{3/2}_2(x+c_{0x})^{1/4}}$. $M$ is the bound state mass. $m_1$ and $m_2$ are the masses of the heavy constituent and the light constituent, respectively. $l$ is the orbital angular momentum and $n_r$ is the radial quantum number. $\beta_x$ and $c_{0x}$ are fitted. $m_1$, $m_2$ and $C'$ are input parameters. These two formulas consider both of the masses of heavy constituent and light constituent. We find that the heavy-light diquarks, the heavy-light mesons, the heavy-light baryons and the heavy-light tetraquarks satisfy these two formulas. When applying the first formula, the heavy-light systems satisfy the universal description irrespective of both of the masses of the light constituents and the heavy constituent. When using the second relation, the heavy-light systems satisfy the universal description irrespective of the mass of the heavy constituent. The fitted slopes differ distinctively for the heavy-light mesons, baryons and tetraquarks, respectively. When employing the first relation, the average values of $c_{fn_r}$ ($c_{fl}$) are $1.026$, $0.794$ and $0.553$ ($1.026$, $0.749$ and $0.579$) for the heavy-light mesons, the heavy-light baryons and the heavy-light tetraquarks, respectively. Upon application of the second relation, the mean values of $c_{fn_r}$ ($c_{fl}$) are $1.108$, $0.896$ and $0.647$ ($1.114$, $0.855$ and $0.676$) for the heavy-light mesons, the heavy-light baryons and the heavy-light tetraquarks, respectively. Moreover, the fitted results show that the Regge trajectories for the heavy-light systems are concave downwards in the $(M^2,\,n_r)$ and $(M^2,\,l)$ planes.
[ { "created": "Tue, 14 Feb 2023 02:25:54 GMT", "version": "v1" }, { "created": "Sun, 18 Feb 2024 02:05:48 GMT", "version": "v2" }, { "created": "Wed, 20 Mar 2024 13:57:25 GMT", "version": "v3" }, { "created": "Thu, 4 Apr 2024 14:41:40 GMT", "version": "v4" } ]
2024-04-05
[ [ "Chen", "Jiao-Kai", "" ] ]
Two newly proposed Regge trajectory relations are employed to analyze the heavy-light systems. One of the relations is $M=m_1+m_2+C'+\beta_x\sqrt{x+c_{0x}}$, $(x=l,\,n_r)$. Another reads $M=m_1+C'+\sqrt{\beta_x^2(x+c_{0x})+\frac{4}{3}\sqrt{{\pi}{\beta_x}}m^{3/2}_2(x+c_{0x})^{1/4}}$. $M$ is the bound state mass. $m_1$ and $m_2$ are the masses of the heavy constituent and the light constituent, respectively. $l$ is the orbital angular momentum and $n_r$ is the radial quantum number. $\beta_x$ and $c_{0x}$ are fitted. $m_1$, $m_2$ and $C'$ are input parameters. These two formulas consider both of the masses of heavy constituent and light constituent. We find that the heavy-light diquarks, the heavy-light mesons, the heavy-light baryons and the heavy-light tetraquarks satisfy these two formulas. When applying the first formula, the heavy-light systems satisfy the universal description irrespective of both of the masses of the light constituents and the heavy constituent. When using the second relation, the heavy-light systems satisfy the universal description irrespective of the mass of the heavy constituent. The fitted slopes differ distinctively for the heavy-light mesons, baryons and tetraquarks, respectively. When employing the first relation, the average values of $c_{fn_r}$ ($c_{fl}$) are $1.026$, $0.794$ and $0.553$ ($1.026$, $0.749$ and $0.579$) for the heavy-light mesons, the heavy-light baryons and the heavy-light tetraquarks, respectively. Upon application of the second relation, the mean values of $c_{fn_r}$ ($c_{fl}$) are $1.108$, $0.896$ and $0.647$ ($1.114$, $0.855$ and $0.676$) for the heavy-light mesons, the heavy-light baryons and the heavy-light tetraquarks, respectively. Moreover, the fitted results show that the Regge trajectories for the heavy-light systems are concave downwards in the $(M^2,\,n_r)$ and $(M^2,\,l)$ planes.
hep-ph/0302142
Igor Shovkovy
Igor Shovkovy and Mei Huang
Gapless two-flavor color superconductor
6 pages, 4 figures. 1 reference and 1 figure are added; the discussion of the effective potential properties is extended
Phys.Lett. B564 (2003) 205
10.1016/S0370-2693(03)00748-2
null
hep-ph astro-ph hep-th nucl-th
null
A new, gapless two-flavor color superconducting phase that appears under conditions of local charge neutrality and $\beta$-equilibrium is revealed. In this phase, the symmetry of the ground state is the same as in the conventional two-flavor color superconductor. In the low-energy spectrum of this phase, however, there are only two gapped fermionic quasiparticles, and the other four quasiparticles are gapless. The origin and the basic properties of the gapless two-flavor color superconductor are discussed. This phase is a natural candidate for quark matter in cores of compact stars.
[ { "created": "Mon, 17 Feb 2003 18:35:48 GMT", "version": "v1" }, { "created": "Tue, 25 Feb 2003 11:46:53 GMT", "version": "v2" }, { "created": "Tue, 22 Apr 2003 15:13:23 GMT", "version": "v3" } ]
2009-11-10
[ [ "Shovkovy", "Igor", "" ], [ "Huang", "Mei", "" ] ]
A new, gapless two-flavor color superconducting phase that appears under conditions of local charge neutrality and $\beta$-equilibrium is revealed. In this phase, the symmetry of the ground state is the same as in the conventional two-flavor color superconductor. In the low-energy spectrum of this phase, however, there are only two gapped fermionic quasiparticles, and the other four quasiparticles are gapless. The origin and the basic properties of the gapless two-flavor color superconductor are discussed. This phase is a natural candidate for quark matter in cores of compact stars.
hep-ph/0307355
Richard Luddy
M. M. Islam, R. J. Luddy, A. V. Prokudin
pp Elastic Scattering at LHC and Nucleon Structure (Conference Report)
6 pages, 12 figures. Presented by M. M. Islam at the Conf. on Intersections of Particle and Nuclear Physics(N.Y., May 2003), the 8th Int. Wigner Symposium (CUNY, N.Y., May 2003) and the 10th Blois Workshop (Helsinki, June 2003). Details of the paper have appeared in: Mod. Phys. Lett. 18(2003)743; hep-ph/0210437
AIP Conf.Proc.698:142-147,2004
10.1063/1.1664213
null
hep-ph
null
High energy elastic pp differential cross section at LHC at the c.m. energy 14 TeV is predicted using the asymptotic behavior of sigma-tot(s) and rho(s), and the measured pbar-p differential cross section at sqrt{s}=546 GeV. The phenomenological investigation has progressively led to an effective field theory model that describes the nucleon as a chiral bag embedded in a quark-antiquark condensed ground state. The measurement of pp elastic scattering at LHC up to large |t| >~ 10 GeV^2 by the TOTEM group will be crucial to test this structure of the nucleon.
[ { "created": "Tue, 29 Jul 2003 19:20:03 GMT", "version": "v1" }, { "created": "Fri, 15 Aug 2003 15:41:40 GMT", "version": "v2" } ]
2011-03-23
[ [ "Islam", "M. M.", "" ], [ "Luddy", "R. J.", "" ], [ "Prokudin", "A. V.", "" ] ]
High energy elastic pp differential cross section at LHC at the c.m. energy 14 TeV is predicted using the asymptotic behavior of sigma-tot(s) and rho(s), and the measured pbar-p differential cross section at sqrt{s}=546 GeV. The phenomenological investigation has progressively led to an effective field theory model that describes the nucleon as a chiral bag embedded in a quark-antiquark condensed ground state. The measurement of pp elastic scattering at LHC up to large |t| >~ 10 GeV^2 by the TOTEM group will be crucial to test this structure of the nucleon.
1204.4152
Sophia Borowka
Sophia Borowka, Jonathon Carter, Gudrun Heinrich
Numerical evaluation of multi-loop integrals for arbitrary kinematics with SecDec 2.0
34 pages, 11 figures, replaced by published version
Comput.Phys.Commun. 184 (2013) 396-408
10.1016/j.cpc.2012.09.020
IPPP/12/22; DCPT/12/44; MPP-2012-75
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the program SecDec 2.0 which contains various new features: First, it allows the numerical evaluation of multi-loop integrals with no restriction on the kinematics. Dimensionally regulated ultraviolet and infrared singularities are isolated via sector decomposition, while threshold singularities are handled by a deformation of the integration contour in the complex plane. As an application we present numerical results for various massive two-loop four-point diagrams. SecDec 2.0 also contains new useful features for the calculation of more general parameter integrals, related e.g. to phase space integrals.
[ { "created": "Wed, 18 Apr 2012 18:04:37 GMT", "version": "v1" }, { "created": "Wed, 29 May 2013 09:36:06 GMT", "version": "v2" } ]
2015-03-20
[ [ "Borowka", "Sophia", "" ], [ "Carter", "Jonathon", "" ], [ "Heinrich", "Gudrun", "" ] ]
We present the program SecDec 2.0 which contains various new features: First, it allows the numerical evaluation of multi-loop integrals with no restriction on the kinematics. Dimensionally regulated ultraviolet and infrared singularities are isolated via sector decomposition, while threshold singularities are handled by a deformation of the integration contour in the complex plane. As an application we present numerical results for various massive two-loop four-point diagrams. SecDec 2.0 also contains new useful features for the calculation of more general parameter integrals, related e.g. to phase space integrals.
2101.06469
Aniello Quaranta
Antonio Capolupo, Salvatore Marco Giampaolo, Aniello Quaranta
Testing CPT violation, entanglement and gravitational interactions in particle mixing with trapped ions
6 pages, 4 figures
The European Physical Journal C volume 81, Article number: 410 (2021)
10.1140/epjc/s10052-021-09194-6
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
By analyzing the analogies between the effective system of $N$ spins described by the Ising Hamiltonian and the phenomenon of the self--gravity in mixed particle systems, we show that cooled ions held in a segmented ion trap and exposed to a magnetic field gradient can simulate the proposed mechanism of mutual interaction in mixed neutrino system. We show that with trapped ions one can reproduce the expected corrections to the flavor transitions and the $CPT$ violation induced by gravity on flavor fields, which may have played an important role in the early stages of the universe. The results presented are experimentally testable. They indicate that ions confined in microtraps can represent a new tool to test fundamental phenomena of nature.
[ { "created": "Sat, 16 Jan 2021 16:08:47 GMT", "version": "v1" } ]
2022-06-14
[ [ "Capolupo", "Antonio", "" ], [ "Giampaolo", "Salvatore Marco", "" ], [ "Quaranta", "Aniello", "" ] ]
By analyzing the analogies between the effective system of $N$ spins described by the Ising Hamiltonian and the phenomenon of the self--gravity in mixed particle systems, we show that cooled ions held in a segmented ion trap and exposed to a magnetic field gradient can simulate the proposed mechanism of mutual interaction in mixed neutrino system. We show that with trapped ions one can reproduce the expected corrections to the flavor transitions and the $CPT$ violation induced by gravity on flavor fields, which may have played an important role in the early stages of the universe. The results presented are experimentally testable. They indicate that ions confined in microtraps can represent a new tool to test fundamental phenomena of nature.
hep-ph/9809475
Costas
C. Panagiotakopoulos, K. Tamvakis
Stabilized NMSSM without Domain Walls
5 pages
Phys.Lett. B446 (1999) 224-227
10.1016/S0370-2693(98)01493-2
null
hep-ph
null
We reconsider the Next to Minimal Supersymmetric Standard Model (NMSSM) as a natural solution to the $\mu$-problem and show that both the stability and the cosmological domain wall problems are eliminated if we impose a ${\cal {Z}}_2$ $R$-symmetry on the non-renormalizable operators.
[ { "created": "Tue, 22 Sep 1998 10:45:45 GMT", "version": "v1" } ]
2009-10-31
[ [ "Panagiotakopoulos", "C.", "" ], [ "Tamvakis", "K.", "" ] ]
We reconsider the Next to Minimal Supersymmetric Standard Model (NMSSM) as a natural solution to the $\mu$-problem and show that both the stability and the cosmological domain wall problems are eliminated if we impose a ${\cal {Z}}_2$ $R$-symmetry on the non-renormalizable operators.
0911.5273
Jong-Chul Park
Eung Jin Chun, Jong-Chul Park, Stefano Scopel
Dirac gaugino as leptophilic dark matter
24 pages, 10 figures, typos corrected, final version published on JCAP
JCAP 1002:015,2010
10.1088/1475-7516/2010/02/015
null
hep-ph astro-ph.CO astro-ph.HE hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the leptophilic properties of Dirac gauginos in an R--symmetric N=2 supersymmetric model with extended gauge and Higgs sectors. The annihilation of Dirac gauginos to leptons requires no chirality flip in the final states so that it is not suppressed as in the Majorana case. This implies that it can be sizable enough to explain the positron excess observed by the PAMELA experiment with moderate or no boost factors. When squark masses are heavy, the annihilation of Dirac gauginos to hadrons is controlled by their Higgsino fraction and is driven by the $hZ$ and $W^+W^-$ final states. Moreover, at variance with the Majorana case, Dirac gauginos with a non-vanishing higgsino fraction can also have a vector coupling with the $Z$ gauge boson leading to a sizable spin--independent scattering cross section off nuclei. Saturating the current antiproton limit, we show that Dirac gauginos can leave a signal in direct detection experiments at the level of the sensitivity of dark matter searches at present and in the near future.
[ { "created": "Fri, 27 Nov 2009 14:14:23 GMT", "version": "v1" }, { "created": "Tue, 8 Dec 2009 08:25:41 GMT", "version": "v2" }, { "created": "Sun, 28 Feb 2010 08:12:06 GMT", "version": "v3" } ]
2010-09-07
[ [ "Chun", "Eung Jin", "" ], [ "Park", "Jong-Chul", "" ], [ "Scopel", "Stefano", "" ] ]
We investigate the leptophilic properties of Dirac gauginos in an R--symmetric N=2 supersymmetric model with extended gauge and Higgs sectors. The annihilation of Dirac gauginos to leptons requires no chirality flip in the final states so that it is not suppressed as in the Majorana case. This implies that it can be sizable enough to explain the positron excess observed by the PAMELA experiment with moderate or no boost factors. When squark masses are heavy, the annihilation of Dirac gauginos to hadrons is controlled by their Higgsino fraction and is driven by the $hZ$ and $W^+W^-$ final states. Moreover, at variance with the Majorana case, Dirac gauginos with a non-vanishing higgsino fraction can also have a vector coupling with the $Z$ gauge boson leading to a sizable spin--independent scattering cross section off nuclei. Saturating the current antiproton limit, we show that Dirac gauginos can leave a signal in direct detection experiments at the level of the sensitivity of dark matter searches at present and in the near future.
hep-ph/9511435
Georges Grunberg
Georges Grunberg
Renormalons and perturbative fixed points
Invited talk at the International Symposium on Heavy Flavor and Electroweak Theory,17-19 August 1995,Beijing,China
null
null
null
hep-ph
null
The connection between renormalons and power corrections is investigated for the typical infrared renormalon integral assuming the effective coupling constant has an infrared fixed point of an entirely perturbative origin. It is shown the full answer differs from the Borel sum by a power correction.
[ { "created": "Tue, 28 Nov 1995 14:32:07 GMT", "version": "v1" } ]
2007-05-23
[ [ "Grunberg", "Georges", "" ] ]
The connection between renormalons and power corrections is investigated for the typical infrared renormalon integral assuming the effective coupling constant has an infrared fixed point of an entirely perturbative origin. It is shown the full answer differs from the Borel sum by a power correction.
hep-ph/9804327
Gi-Chol Cho
Gi-Chol Cho (Theory group, KEK)
Impacts on searching for signatures of new physics from $K^+ \to \pi^+ \nu \bar{\nu}$ decay
LaTeX, 12 pages, 3 figures, talk given at the workshop on Fermion Mass and CP violation, Hiroshima, Japan, 5-6 March 1998
null
null
KEK-TH-568
hep-ph
null
Impacts on new physics search from $\bbbar, \kkbar$ mixings and the rare decay $\kplusdecay$ are discussed. We show that, in a certain class of new physics models, the extra contributions to those processes can be parametrized by its ratio to the standard model (SM) contribution with the common CKM factors. We introduce two ratios to measure the new physics contributions, $R_1$ for $\xd$ and $\ek$ parameters, and $R_2$ for $\kplusdecay$ decay. Then, the experimentally allowed region for the new physics contributions can be given in terms of $R_1, R_2$ and the CP violating phase $\delta$ of the CKM matrix. We find constraints on $R_1$ and $\cosd$ by taking account of current experimental data and theoretical uncertainties on $\bbbar$ and $\kkbar$ mixings. We also study impacts of future improved measurements on ($R_1,R_2,\cosd$) basis. As typical examples of new physics models, we examine contributions to those processes in the minimal supersymmetric SM and the two Higgs doublet model.
[ { "created": "Mon, 20 Apr 1998 05:51:29 GMT", "version": "v1" } ]
2007-05-23
[ [ "Cho", "Gi-Chol", "", "Theory group, KEK" ] ]
Impacts on new physics search from $\bbbar, \kkbar$ mixings and the rare decay $\kplusdecay$ are discussed. We show that, in a certain class of new physics models, the extra contributions to those processes can be parametrized by its ratio to the standard model (SM) contribution with the common CKM factors. We introduce two ratios to measure the new physics contributions, $R_1$ for $\xd$ and $\ek$ parameters, and $R_2$ for $\kplusdecay$ decay. Then, the experimentally allowed region for the new physics contributions can be given in terms of $R_1, R_2$ and the CP violating phase $\delta$ of the CKM matrix. We find constraints on $R_1$ and $\cosd$ by taking account of current experimental data and theoretical uncertainties on $\bbbar$ and $\kkbar$ mixings. We also study impacts of future improved measurements on ($R_1,R_2,\cosd$) basis. As typical examples of new physics models, we examine contributions to those processes in the minimal supersymmetric SM and the two Higgs doublet model.
hep-ph/0703217
Anne Green
Anne M Green
Determining the WIMP mass using direct detection experiments
19 pages, 8 figures, version to appear in JCAP, minor changes to discussion
JCAP0708:022,2007
10.1088/1475-7516/2007/08/022
null
hep-ph astro-ph hep-ex
null
We study the accuracy with which the WIMP mass could be determined by a superCDMS-like direct detection experiment, given optimistic assumptions about the detector set-up and WIMP properties. We consider WIMPs with an interaction cross-section of \sigma_{\rm p} = 10^{-7} {\rm pb} (just below current exclusion limits) and assume, initially, that the local WIMP velocity distribution and density are known and that the experiment has negligible background. For light WIMPs (mass significantly less than that of the target nuclei) small variations in the WIMP mass lead to significant changes in the energy spectrum. Conversely for heavy WIMPs the energy spectrum depends only weakly on the WIMP mass. Consequently it will be far easier to measure the WIMP mass if it is light than if it is heavy. With exposures of {\cal E}= 3 \times 10^{3}, 3 \times 10^{4} and 3 \times 10^{5} {\rm kg day} (corresponding, roughly, to the three proposed phases of SuperCDMS) it will be possible, given the optimistic assumptions mentioned above, to measure the mass of a light WIMP with an accuracy of roughly 25%, 15% and 2.5 % respectively. These numbers increase with increasing WIMP mass, and for heavy WIMPs, m_{\chi} > {\cal O}(500 {\rm GeV}), even with a large exposure it will only be possible to place a lower limit on the mass. Finally we discuss the validity of the various assumptions made, and the consequences if these assumptions are not valid. In particular if the local WIMP distribution is composed of a number of discrete streams it will not be possible to determine the WIMP mass.
[ { "created": "Tue, 20 Mar 2007 13:52:03 GMT", "version": "v1" }, { "created": "Tue, 7 Aug 2007 21:15:16 GMT", "version": "v2" } ]
2008-11-26
[ [ "Green", "Anne M", "" ] ]
We study the accuracy with which the WIMP mass could be determined by a superCDMS-like direct detection experiment, given optimistic assumptions about the detector set-up and WIMP properties. We consider WIMPs with an interaction cross-section of \sigma_{\rm p} = 10^{-7} {\rm pb} (just below current exclusion limits) and assume, initially, that the local WIMP velocity distribution and density are known and that the experiment has negligible background. For light WIMPs (mass significantly less than that of the target nuclei) small variations in the WIMP mass lead to significant changes in the energy spectrum. Conversely for heavy WIMPs the energy spectrum depends only weakly on the WIMP mass. Consequently it will be far easier to measure the WIMP mass if it is light than if it is heavy. With exposures of {\cal E}= 3 \times 10^{3}, 3 \times 10^{4} and 3 \times 10^{5} {\rm kg day} (corresponding, roughly, to the three proposed phases of SuperCDMS) it will be possible, given the optimistic assumptions mentioned above, to measure the mass of a light WIMP with an accuracy of roughly 25%, 15% and 2.5 % respectively. These numbers increase with increasing WIMP mass, and for heavy WIMPs, m_{\chi} > {\cal O}(500 {\rm GeV}), even with a large exposure it will only be possible to place a lower limit on the mass. Finally we discuss the validity of the various assumptions made, and the consequences if these assumptions are not valid. In particular if the local WIMP distribution is composed of a number of discrete streams it will not be possible to determine the WIMP mass.
hep-ph/0209239
Thorsten Feldmann
Thorsten Feldmann (RWTH Aachen)
Heavy-to-light decays at large recoil: Systematic treatment of short- and long-distance QCD effects
Talk presented at QCD'02 conference, July 2002, Montpellier (France); 4 pages, 1 figure, uses espcrc2.sty
null
10.1016/S0920-5632(03)01861-9
null
hep-ph
null
Heavy quark decays into energetic, collinear quarks and gluons are discussed within an effective theory that accomplishes the factorization of soft and hard strong interaction effects. We derive the relevant effective Lagrangian, and perform the matching of the heavy quark current, including power corrections of order 1/m, where m is the heavy quark mass. We apply our framework to heavy-to-light form factors.
[ { "created": "Fri, 20 Sep 2002 13:49:23 GMT", "version": "v1" } ]
2009-11-07
[ [ "Feldmann", "Thorsten", "", "RWTH Aachen" ] ]
Heavy quark decays into energetic, collinear quarks and gluons are discussed within an effective theory that accomplishes the factorization of soft and hard strong interaction effects. We derive the relevant effective Lagrangian, and perform the matching of the heavy quark current, including power corrections of order 1/m, where m is the heavy quark mass. We apply our framework to heavy-to-light form factors.
hep-ph/9502319
null
R. Engel, J. Ranft, S. Roesler
Hard diffraction in hadron--hadron interactions and in photoproduction
13 pages, Latex, 13 uuencoded figures
Phys.Rev. D52 (1995) 1459-1468
10.1103/PhysRevD.52.1459
SI 95-16
hep-ph
null
Hard single diffractive processes are studied within the framework of the triple--Pomeron approximation. Using a Pomeron structure function motivated by Regge--theory we obtain parton distribution functions which do not obey momentum sum rule. Based on Regge-- factorization cross sections for hard diffraction are calculated. Furthermore, the model is applied to hard diffractive particle production in photoproduction and in $p\bar{p}$ interactions.
[ { "created": "Thu, 16 Feb 1995 13:33:45 GMT", "version": "v1" } ]
2016-09-01
[ [ "Engel", "R.", "" ], [ "Ranft", "J.", "" ], [ "Roesler", "S.", "" ] ]
Hard single diffractive processes are studied within the framework of the triple--Pomeron approximation. Using a Pomeron structure function motivated by Regge--theory we obtain parton distribution functions which do not obey momentum sum rule. Based on Regge-- factorization cross sections for hard diffraction are calculated. Furthermore, the model is applied to hard diffractive particle production in photoproduction and in $p\bar{p}$ interactions.
1407.7963
Michael Klasen
B. Fuks, M. Klasen, D.R. Lamprea, M. Rothering
Precision predictions for direct gaugino and slepton production at the LHC
5 pages, 2 tables, 5 figures, proceedings of ICHEP 2014
null
null
CERN-PH-TH-2014-144, MS-TP-14-26
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The search for electroweak superpartners has recently moved to the centre of interest at the LHC. We provide the currently most precise theoretical predictions for these particles, use them to assess the precision of parton shower simulations, and reanalyse public experimental results assuming more general decompositions of gauginos and sleptons.
[ { "created": "Wed, 30 Jul 2014 07:51:21 GMT", "version": "v1" } ]
2014-07-31
[ [ "Fuks", "B.", "" ], [ "Klasen", "M.", "" ], [ "Lamprea", "D. R.", "" ], [ "Rothering", "M.", "" ] ]
The search for electroweak superpartners has recently moved to the centre of interest at the LHC. We provide the currently most precise theoretical predictions for these particles, use them to assess the precision of parton shower simulations, and reanalyse public experimental results assuming more general decompositions of gauginos and sleptons.
0911.1534
David Blaschke
Jakub Jankowski, David Blaschke, Hovik Grigorian
Quarkonium dissociation in a PNJL quark plasma
6 pages, 1 figure, contribution to EMMI Workshop and XXVI Max-Born Symposium "Three Days of Strong Interactions", Wroclaw, July 9-11, 2009
Acta Phys.Polon.Supp.3:747-752,2010
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the Mott effect for heavy quarkonia due to Debye screening of the heavy quark potential in a plasma of massless quarks and antiquarks. The influence of residual color correlation is investigated by coupling the light quark sector to a temporal gauge field driven by the Polyakov loop potential. This leads to an increase of the Mott dissociation temperatures for quarkonia states which stabilizes in particular the excited states, but has marginal effect on the ground states. The temperature dependence of binding energies suggests that the dissciation of the charmonium (bottomonium) ground state by thermal activation sets in at temperatures of 200 MeV (250 MeV).
[ { "created": "Sun, 8 Nov 2009 15:23:49 GMT", "version": "v1" } ]
2010-11-02
[ [ "Jankowski", "Jakub", "" ], [ "Blaschke", "David", "" ], [ "Grigorian", "Hovik", "" ] ]
We investigate the Mott effect for heavy quarkonia due to Debye screening of the heavy quark potential in a plasma of massless quarks and antiquarks. The influence of residual color correlation is investigated by coupling the light quark sector to a temporal gauge field driven by the Polyakov loop potential. This leads to an increase of the Mott dissociation temperatures for quarkonia states which stabilizes in particular the excited states, but has marginal effect on the ground states. The temperature dependence of binding energies suggests that the dissciation of the charmonium (bottomonium) ground state by thermal activation sets in at temperatures of 200 MeV (250 MeV).
hep-ph/0208262
B. Field
B. Field (Stony Brook, BNL)
Distinguishing scalar from pseudoscalar Higgs production at the LHC
7 pages, REVTeX4, 4 eps figures. Figure 1 and 4 replaced. Typos corrected, additional reference added
Phys.Rev.D66:114007,2002
10.1103/PhysRevD.66.114007
YITP-SB-02-47, BNL-HET-02/19
hep-ph
null
In this letter we examine the production channels for the scalar or pseudoscalar Higgs plus two jets at the CERN Large Hadron Collider (LHC). We identify possible signals for distinguishing between a scalar and a pseudoscalar Higgs boson.
[ { "created": "Thu, 29 Aug 2002 17:24:51 GMT", "version": "v1" }, { "created": "Tue, 24 Sep 2002 15:58:13 GMT", "version": "v2" }, { "created": "Fri, 27 Sep 2002 17:24:52 GMT", "version": "v3" }, { "created": "Thu, 17 Oct 2002 21:50:30 GMT", "version": "v4" } ]
2008-11-26
[ [ "Field", "B.", "", "Stony Brook, BNL" ] ]
In this letter we examine the production channels for the scalar or pseudoscalar Higgs plus two jets at the CERN Large Hadron Collider (LHC). We identify possible signals for distinguishing between a scalar and a pseudoscalar Higgs boson.
1504.01324
Frans Klinkhamer
J.S. Diaz, F.R. Klinkhamer
Parton-model calculation of a nonstandard decay process in isotropic modified Maxwell theory
16 pages, v5: published version
Phys. Rev. D 92, 025007 (2015)
10.1103/PhysRevD.92.025007
KA-TP-06-2015
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have performed a calculation in the parton-model approximation of a nonstandard decay process in isotropic modified Maxwell theory coupled to standard Dirac theory, with a single Lorentz-violating parameter $\kappa$ in the photonic sector. Previous calculations of this process (vacuum Cherenkov radiation by a proton for the theory with $\kappa>0$) were performed for pointlike particles, and an upper bound on $\kappa$ at the $10^{-19}$ level was obtained from experimental data on ultra-high-energy cosmic rays. The parton-model results change the decay rate by about an order of magnitude but give the same upper bound on $\kappa$ because the threshold energy is unchanged. The previous point-particle calculation of photon decay into an electron-positron pair for the theory with $\kappa<0$ remains valid, and experimental results on cosmic gamma rays provide a lower bound on $\kappa$ at the $-10^{-15}$ level.
[ { "created": "Mon, 6 Apr 2015 17:22:05 GMT", "version": "v1" }, { "created": "Thu, 9 Apr 2015 18:47:23 GMT", "version": "v2" }, { "created": "Thu, 16 Apr 2015 15:35:57 GMT", "version": "v3" }, { "created": "Wed, 10 Jun 2015 17:24:38 GMT", "version": "v4" }, { "created": "Thu, 2 Jul 2015 18:26:55 GMT", "version": "v5" } ]
2015-08-06
[ [ "Diaz", "J. S.", "" ], [ "Klinkhamer", "F. R.", "" ] ]
We have performed a calculation in the parton-model approximation of a nonstandard decay process in isotropic modified Maxwell theory coupled to standard Dirac theory, with a single Lorentz-violating parameter $\kappa$ in the photonic sector. Previous calculations of this process (vacuum Cherenkov radiation by a proton for the theory with $\kappa>0$) were performed for pointlike particles, and an upper bound on $\kappa$ at the $10^{-19}$ level was obtained from experimental data on ultra-high-energy cosmic rays. The parton-model results change the decay rate by about an order of magnitude but give the same upper bound on $\kappa$ because the threshold energy is unchanged. The previous point-particle calculation of photon decay into an electron-positron pair for the theory with $\kappa<0$ remains valid, and experimental results on cosmic gamma rays provide a lower bound on $\kappa$ at the $-10^{-15}$ level.
0906.4412
Chien-Wen Hwang
Chien-Wen Hwang
Leading-twist light cone distribution amplitudes for p-wave heavy quarkonium states
25 pages, 2 figures, some details and one reference added; version to appear in JHEP
JHEP 0910:074,2009
10.1088/1126-6708/2009/10/074
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, a study of light-cone distribution amplitudes for p-wave heavy quarkonium states are presented. Within the light-front framework, the leading twist light-cone distribution amplitudes, and their relevant decay constants, have some simple relations. These relations can be further simplified when the non-relativistic limit and the wave function as a function of relative momentum |\vec\kappa| are taken into consideration. In addition, the \kappa_\perp integrations in the equations of LCDAs and \xi-moments can be completed analytically when the Gaussian-type wave function is considered. After fixing the parameters that appear in the wave function, the curves and the corresponding decay constants of the LCDAs are plotted and calculated for the charmonium and bottomonium states. The first three \xi-moments of the LCDAs are estimated and are consistent with those of other theoretical approaches.
[ { "created": "Wed, 24 Jun 2009 07:18:36 GMT", "version": "v1" }, { "created": "Mon, 26 Oct 2009 09:42:12 GMT", "version": "v2" } ]
2009-11-05
[ [ "Hwang", "Chien-Wen", "" ] ]
In this paper, a study of light-cone distribution amplitudes for p-wave heavy quarkonium states are presented. Within the light-front framework, the leading twist light-cone distribution amplitudes, and their relevant decay constants, have some simple relations. These relations can be further simplified when the non-relativistic limit and the wave function as a function of relative momentum |\vec\kappa| are taken into consideration. In addition, the \kappa_\perp integrations in the equations of LCDAs and \xi-moments can be completed analytically when the Gaussian-type wave function is considered. After fixing the parameters that appear in the wave function, the curves and the corresponding decay constants of the LCDAs are plotted and calculated for the charmonium and bottomonium states. The first three \xi-moments of the LCDAs are estimated and are consistent with those of other theoretical approaches.
hep-ph/9308259
Poul H. Damgaard
P.H. Damgaard, H.B. Nielsen and R. Sollacher
Gauge-Symmetric Approach to Effective Lagrangians: The \eta' Meson from QCD
LaTeX, 31 pages, CERN--TH-6959/93
Nucl.Phys. B414 (1994) 541-578
10.1016/0550-3213(94)90254-2
null
hep-ph
null
We present a general scheme for extracting effective degrees of freedom from an underlying fundamental Lagrangian, through a series of well-defined transformations in the functional integral of the cut-off theory. This is done by introducing collective fields in a gauge-symmetric manner. Through appropriate gauge fixings of this symmetry one can remove long-distance degrees of freedom from the underlying theory, replacing them by the collective fields. Applying this technique to QCD, we set out to extract the long-distance dynamics in the pseudoscalar flavour singlet sector through a gauging (and subsequent gauge fixing) of the $U(1)_A$ flavour symmetry which is broken by the anomaly. By this series of exact transformations of a cut-off generating functional for QCD, we arrive at a theory describing the long-distance physics of a pseudoscalar flavour singlet meson coupled to the residual quark-gluon degrees of freedom. As examples of how known low-energy physics can be reproduced in this formulation, we rederive the Witten-Veneziano relation between the $\eta'$ mass and the topological susceptibility, now for any value of the number of colours $N_c$.
[ { "created": "Wed, 11 Aug 1993 14:18:35 GMT", "version": "v1" } ]
2009-10-22
[ [ "Damgaard", "P. H.", "" ], [ "Nielsen", "H. B.", "" ], [ "Sollacher", "R.", "" ] ]
We present a general scheme for extracting effective degrees of freedom from an underlying fundamental Lagrangian, through a series of well-defined transformations in the functional integral of the cut-off theory. This is done by introducing collective fields in a gauge-symmetric manner. Through appropriate gauge fixings of this symmetry one can remove long-distance degrees of freedom from the underlying theory, replacing them by the collective fields. Applying this technique to QCD, we set out to extract the long-distance dynamics in the pseudoscalar flavour singlet sector through a gauging (and subsequent gauge fixing) of the $U(1)_A$ flavour symmetry which is broken by the anomaly. By this series of exact transformations of a cut-off generating functional for QCD, we arrive at a theory describing the long-distance physics of a pseudoscalar flavour singlet meson coupled to the residual quark-gluon degrees of freedom. As examples of how known low-energy physics can be reproduced in this formulation, we rederive the Witten-Veneziano relation between the $\eta'$ mass and the topological susceptibility, now for any value of the number of colours $N_c$.
hep-ph/0310297
Mariana Kirchbach
M. Kirchbach, C. Compean, L. Noriega
Neutral Fermion Phenomenology With Majorana Spinors
24 pages, Elsevier LaTex; upgraded version-several statements reformulated more precisely, new subsection 2.5
null
null
UASLP-IF-04-001
hep-ph
null
We ask the question whether neutrino physics with momentum space Majorana spinors, the eigenvectors of the particle--antiparticle conjugation operator, C=i\gamma_2 K (with K standing for complex conjugation), is different but physics with Dirac spinors. First we analyze properties of Majorana spinors in great detail. We show that four dimensional, (4d), Majorana spinors are unsuited for the construction of a local quantum field because C invariance does not allow for a covariant propagation in four spinor dimensions, a conduct due to \gamma_2\gamma_\mu= -\gamma_\mu * \gamma_2. The way out of this dilemma is finding one more discrete symmetry that respects C invariance and gives rise to covariant propagators. We construct such a symmetry in observing that the parity operator, \gamma_0, ``ladders'' between (4d) rest-frame Majorana spinors, which takes us to eight dimensional spinor spaces. We build up two types of (8d) spaces-- one with a symmetric- and an other with an anti-symmetric off diagonal metric and calculate traces of single beta-- and neutrinoless double beta (0\nu\beta \beta) decays there. We find physics with (8d) Majorana spinors in the former space to be equivalent to physics with Dirac spinors in four dimensions. In the latter space we make the rare observation that in effect of cancellations triggered by the anti-symmetric off diagonal (8d) metric, the neutrino mass drops from the single beta decay trace but reappears in 0\nu \beta\beta, without the neutrino being massless in its free equation-- a curious and in principle experimentally testable signature for a non-trivial impact of Majorana framework.
[ { "created": "Mon, 27 Oct 2003 16:43:41 GMT", "version": "v1" }, { "created": "Sat, 8 May 2004 02:11:45 GMT", "version": "v2" } ]
2007-05-23
[ [ "Kirchbach", "M.", "" ], [ "Compean", "C.", "" ], [ "Noriega", "L.", "" ] ]
We ask the question whether neutrino physics with momentum space Majorana spinors, the eigenvectors of the particle--antiparticle conjugation operator, C=i\gamma_2 K (with K standing for complex conjugation), is different but physics with Dirac spinors. First we analyze properties of Majorana spinors in great detail. We show that four dimensional, (4d), Majorana spinors are unsuited for the construction of a local quantum field because C invariance does not allow for a covariant propagation in four spinor dimensions, a conduct due to \gamma_2\gamma_\mu= -\gamma_\mu * \gamma_2. The way out of this dilemma is finding one more discrete symmetry that respects C invariance and gives rise to covariant propagators. We construct such a symmetry in observing that the parity operator, \gamma_0, ``ladders'' between (4d) rest-frame Majorana spinors, which takes us to eight dimensional spinor spaces. We build up two types of (8d) spaces-- one with a symmetric- and an other with an anti-symmetric off diagonal metric and calculate traces of single beta-- and neutrinoless double beta (0\nu\beta \beta) decays there. We find physics with (8d) Majorana spinors in the former space to be equivalent to physics with Dirac spinors in four dimensions. In the latter space we make the rare observation that in effect of cancellations triggered by the anti-symmetric off diagonal (8d) metric, the neutrino mass drops from the single beta decay trace but reappears in 0\nu \beta\beta, without the neutrino being massless in its free equation-- a curious and in principle experimentally testable signature for a non-trivial impact of Majorana framework.
hep-ph/9507289
null
Kenneth Lane
Color-Singlet Technipions at the Tevatron
12 pages, TeX using harmac macros; two uuencoded figures
Phys.Lett. B357 (1995) 624-629
10.1016/0370-2693(95)00960-S
BUHEP-95-23
hep-ph hep-ex
null
I discuss production and detection at the Tevatron $\pbarp$ collider of pairs of light ($\mpi = 100$--$200\,\gev$) color--singlet technipions that are expected in all nonminimal models of technicolor. Gluon fusion production rates can be as large as $\CO(1\,\pb)$. Topcolor--assisted technicolor is required to prevent top quarks from decaying as $t \ra \tpip b$. An intriguing consequence of this is that the decays $\tpip \ra \tau^+ \nu_\tau$, $c \ol s$ and $\tpiz \ra b \ol b$ may also be suppressed so that $\tpip \ra W^+ \gamma$ and $\tpiz \ra \gamma\gamma$ are significant. These modes have spectactular signatures at the Tevatron.
[ { "created": "Wed, 12 Jul 1995 00:02:01 GMT", "version": "v1" } ]
2009-10-28
[ [ "Lane", "Kenneth", "" ] ]
I discuss production and detection at the Tevatron $\pbarp$ collider of pairs of light ($\mpi = 100$--$200\,\gev$) color--singlet technipions that are expected in all nonminimal models of technicolor. Gluon fusion production rates can be as large as $\CO(1\,\pb)$. Topcolor--assisted technicolor is required to prevent top quarks from decaying as $t \ra \tpip b$. An intriguing consequence of this is that the decays $\tpip \ra \tau^+ \nu_\tau$, $c \ol s$ and $\tpiz \ra b \ol b$ may also be suppressed so that $\tpip \ra W^+ \gamma$ and $\tpiz \ra \gamma\gamma$ are significant. These modes have spectactular signatures at the Tevatron.
1110.3951
Michael Baker
Michael J. Baker, J. Bordes, H. M. Chan, S. T. Tsou
On the Corner Elements of the CKM and PMNS Matrices
9 pages, 2 figures, updated with new experimental data and more details
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent experiments show that the top-right corner element ($U_{e3}$) of the PMNS, like that ($V_{ub}$) of the CKM, matrix is small but nonzero, and suggest further via unitarity that it is smaller than the bottom-left corner element ($U_{\tau 1}$), again as in the CKM case ($V_{ub} < V_{td}$). An attempt in explaining these facts would seem an excellent test for any model of the mixing phenomenon. Here, it is shown that if to the assumption of a universal rank-one mass matrix, long favoured by phenomenologists, one adds that this matrix rotates with scale, then it follows that (A) by inputting the mass ratios $m_c/m_t, m_s/m_b, m_\mu/m_\tau$, and $m_2/m_3$, (i) the corner elements are small but nonzero, (ii) $V_{ub} < V_{td}$, $U_{e 3} < U_{\tau 1}$, (iii) estimates result for the ratios $V_{ub}/V_{td}$ and $U_{e 3}/U_{\tau 1}$, and (B) by inputting further the experimental values of $V_{us}, V_{tb}$ and $U_{e2},U_{\mu 3}$, (iv) estimates result for the values of the corner elements themselves. All the inequalities and estimates obtained are consistent with present data to within expectation for the approximations made.
[ { "created": "Tue, 18 Oct 2011 12:24:45 GMT", "version": "v1" }, { "created": "Fri, 1 Jun 2012 14:45:11 GMT", "version": "v2" } ]
2012-06-04
[ [ "Baker", "Michael J.", "" ], [ "Bordes", "J.", "" ], [ "Chan", "H. M.", "" ], [ "Tsou", "S. T.", "" ] ]
Recent experiments show that the top-right corner element ($U_{e3}$) of the PMNS, like that ($V_{ub}$) of the CKM, matrix is small but nonzero, and suggest further via unitarity that it is smaller than the bottom-left corner element ($U_{\tau 1}$), again as in the CKM case ($V_{ub} < V_{td}$). An attempt in explaining these facts would seem an excellent test for any model of the mixing phenomenon. Here, it is shown that if to the assumption of a universal rank-one mass matrix, long favoured by phenomenologists, one adds that this matrix rotates with scale, then it follows that (A) by inputting the mass ratios $m_c/m_t, m_s/m_b, m_\mu/m_\tau$, and $m_2/m_3$, (i) the corner elements are small but nonzero, (ii) $V_{ub} < V_{td}$, $U_{e 3} < U_{\tau 1}$, (iii) estimates result for the ratios $V_{ub}/V_{td}$ and $U_{e 3}/U_{\tau 1}$, and (B) by inputting further the experimental values of $V_{us}, V_{tb}$ and $U_{e2},U_{\mu 3}$, (iv) estimates result for the values of the corner elements themselves. All the inequalities and estimates obtained are consistent with present data to within expectation for the approximations made.
hep-ph/9506254
null
M. Takizawa (Institute for Nuclear Study, University of Tokyo), and M. Oka (Department of Physics, Tokyo Institute of Technology)
Effects of the $U_A(1)$ Anomaly on $\eta \to 2 \gamma$ Decay
12 pages, 3 Postscript figures
Phys.Lett. B359 (1995) 210-216; Erratum-ibid. B364 (1995) 249
10.1016/0370-2693(95)01362-8
INS-Rep.-1101 and TIT/HEP-295/NP
hep-ph nucl-th
null
We study the $\eta \to 2 \gamma$ decay using an extended three-flavor Nambu-Jona-Lasinio model that includes the 't~Hooft instanton induced interaction. The $\eta$ meson mass and the $\eta \to 2 \gamma$ decay width are reproduced simultaneously with a rather strong instanton induced interaction. The calculated $\eta$ decay constant is $f_\eta = 2.23 f_\pi$ and it suggests that the $\eta$ meson is no longer the Goldstone boson.
[ { "created": "Wed, 7 Jun 1995 05:44:41 GMT", "version": "v1" } ]
2009-10-28
[ [ "Takizawa", "M.", "", "Institute for Nuclear Study, University of Tokyo" ], [ "Oka", "M.", "", "Department of Physics, Tokyo Institute of Technology" ] ]
We study the $\eta \to 2 \gamma$ decay using an extended three-flavor Nambu-Jona-Lasinio model that includes the 't~Hooft instanton induced interaction. The $\eta$ meson mass and the $\eta \to 2 \gamma$ decay width are reproduced simultaneously with a rather strong instanton induced interaction. The calculated $\eta$ decay constant is $f_\eta = 2.23 f_\pi$ and it suggests that the $\eta$ meson is no longer the Goldstone boson.
hep-ph/0211348
Eugene Levin
Michael Kozlov and Eugene Levin
QCD Saturation and $\gamma^*-\gamma^*$ Scattering
19 pages, 8 figures
Eur.Phys.J.C28:483-493,2003
10.1140/epjc/s2003-01174-8
DESY-02-206, TAUP-2727-2002
hep-ph
null
Two photon collisions at high energy have an important theoretical advantage: the simplicity of the initial state, which gives us a unique opportunity to calculate these processes for large virtualities of both photons in perturbative QCD approach. In this paper we study QCD saturation in two photon collisions in the framework of the Glauber-Mueller approach. The Glauber-Mueller formula is derived emphasizing the impact parameter dependence ($b_t$) of the dipole-dipole amplitude. It is shown that non-perturbative QCD contributions are needed to describe large $b_t $-behaviour, and the way how to deal with them is suggested. Our approach can be viewed as the model for the saturation in which the entire impact parameter dependence is determined by the initial conditions. The unitarity bound for the total cross section, its energy dependence as well aspredictions for future experiments are discussed.It is argued that the total cross section increases faster than any power of $ \log(1/x)$ in a wide range of energy or $x$, namely $\sigma(\gamma^*-\gamma^*) \propto (1/Q^2) exp(a \sqrt{\ln(1/x)}) \leq 1/m^2_{\pi}$ where $exp(a \sqrt{\ln(1/x)})$ reflects the $x$ dependence of the gluon density $xG \propto exp(2 a \sqrt{\ln(1/x)})$ and $m_{\pi}$ is the pion mass.
[ { "created": "Fri, 22 Nov 2002 09:21:16 GMT", "version": "v1" }, { "created": "Mon, 10 Feb 2003 09:04:59 GMT", "version": "v2" } ]
2011-09-13
[ [ "Kozlov", "Michael", "" ], [ "Levin", "Eugene", "" ] ]
Two photon collisions at high energy have an important theoretical advantage: the simplicity of the initial state, which gives us a unique opportunity to calculate these processes for large virtualities of both photons in perturbative QCD approach. In this paper we study QCD saturation in two photon collisions in the framework of the Glauber-Mueller approach. The Glauber-Mueller formula is derived emphasizing the impact parameter dependence ($b_t$) of the dipole-dipole amplitude. It is shown that non-perturbative QCD contributions are needed to describe large $b_t $-behaviour, and the way how to deal with them is suggested. Our approach can be viewed as the model for the saturation in which the entire impact parameter dependence is determined by the initial conditions. The unitarity bound for the total cross section, its energy dependence as well aspredictions for future experiments are discussed.It is argued that the total cross section increases faster than any power of $ \log(1/x)$ in a wide range of energy or $x$, namely $\sigma(\gamma^*-\gamma^*) \propto (1/Q^2) exp(a \sqrt{\ln(1/x)}) \leq 1/m^2_{\pi}$ where $exp(a \sqrt{\ln(1/x)})$ reflects the $x$ dependence of the gluon density $xG \propto exp(2 a \sqrt{\ln(1/x)})$ and $m_{\pi}$ is the pion mass.
hep-ph/0211462
Carlo Giunti
S.M. Bilenky, C. Giunti, J.A. Grifols, E. Masso
Absolute Values of Neutrino Masses: Status and Prospects
92 pages. Final version to be published in Phys. Rep., with note on implications of recent WMAP results
Phys.Rept.379:69-148,2003
10.1016/S0370-1573(03)00102-9
UAB-FT-533, KIAS-P02070
hep-ph astro-ph hep-ex
null
Compelling evidences in favor of neutrino masses and mixing obtained in the last years in Super-Kamiokande, SNO, KamLAND and other neutrino experiments made the physics of massive and mixed neutrinos a frontier field of research in particle physics and astrophysics. There are many open problems in this new field. In this review we consider the problem of the absolute values of neutrino masses, which apparently is the most difficult one from the experimental point of view. We discuss the present limits and the future prospects of beta-decay neutrino mass measurements and neutrinoless double-beta decay. We consider the important problem of the calculation of nuclear matrix elements of neutrinoless double-beta decay and discuss the possibility to check the results of different model calculations of the nuclear matrix elements through their comparison with the experimental data. We discuss the upper bound of the total mass of neutrinos that was obtained recently from the data of the 2dF Galaxy Redshift Survey and other cosmological data and we discuss future prospects of the cosmological measurements of the total mass of neutrinos. We discuss also the possibility to obtain information on neutrino masses from the observation of the ultra high-energy cosmic rays (beyond the GZK cutoff). Finally, we review the main aspects of the physics of core-collapse supernovae, the limits on the absolute values of neutrino masses from the observation of SN1987A neutrinos and the future prospects of supernova neutrino detection.
[ { "created": "Fri, 29 Nov 2002 16:35:03 GMT", "version": "v1" }, { "created": "Mon, 3 Feb 2003 10:18:49 GMT", "version": "v2" }, { "created": "Thu, 27 Mar 2003 15:32:32 GMT", "version": "v3" } ]
2008-11-26
[ [ "Bilenky", "S. M.", "" ], [ "Giunti", "C.", "" ], [ "Grifols", "J. A.", "" ], [ "Masso", "E.", "" ] ]
Compelling evidences in favor of neutrino masses and mixing obtained in the last years in Super-Kamiokande, SNO, KamLAND and other neutrino experiments made the physics of massive and mixed neutrinos a frontier field of research in particle physics and astrophysics. There are many open problems in this new field. In this review we consider the problem of the absolute values of neutrino masses, which apparently is the most difficult one from the experimental point of view. We discuss the present limits and the future prospects of beta-decay neutrino mass measurements and neutrinoless double-beta decay. We consider the important problem of the calculation of nuclear matrix elements of neutrinoless double-beta decay and discuss the possibility to check the results of different model calculations of the nuclear matrix elements through their comparison with the experimental data. We discuss the upper bound of the total mass of neutrinos that was obtained recently from the data of the 2dF Galaxy Redshift Survey and other cosmological data and we discuss future prospects of the cosmological measurements of the total mass of neutrinos. We discuss also the possibility to obtain information on neutrino masses from the observation of the ultra high-energy cosmic rays (beyond the GZK cutoff). Finally, we review the main aspects of the physics of core-collapse supernovae, the limits on the absolute values of neutrino masses from the observation of SN1987A neutrinos and the future prospects of supernova neutrino detection.
1103.3645
Franz Herzog
Charalampos Anastasiou, Stephan Buehler, Elisabetta Furlan, Franz Herzog, Achilleas Lazopoulos
Higgs production cross-section in a Standard Model with four generations at the LHC
6 pages, 2 Tables, to appear in the proceedings of the XLVIth Rencontres de Moriond session devoted to Electroweak Interactions and Unified Theories
null
10.1016/j.physletb.2011.06.097
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present theoretical predictions for the Higgs boson production cross-section via gluon fusion at the LHC in a Standard Model with four generations. We include QCD corrections through NLO retaining the full dependence on the quark masses, and the NNLO corrections in the heavy quark effective theory approximation. We also include electroweak corrections through three loops. Electroweak and bottom-quark contributions are suppressed in comparison to the Standard Model with three generations.
[ { "created": "Fri, 18 Mar 2011 15:02:19 GMT", "version": "v1" } ]
2015-05-27
[ [ "Anastasiou", "Charalampos", "" ], [ "Buehler", "Stephan", "" ], [ "Furlan", "Elisabetta", "" ], [ "Herzog", "Franz", "" ], [ "Lazopoulos", "Achilleas", "" ] ]
We present theoretical predictions for the Higgs boson production cross-section via gluon fusion at the LHC in a Standard Model with four generations. We include QCD corrections through NLO retaining the full dependence on the quark masses, and the NNLO corrections in the heavy quark effective theory approximation. We also include electroweak corrections through three loops. Electroweak and bottom-quark contributions are suppressed in comparison to the Standard Model with three generations.
0802.0321
Cristina Manuel
Massimo Mannarelli and Cristina Manuel
Transport theory for cold relativistic superfluids from an analogue model of gravity
14 pages
Phys.Rev.D77:103014,2008
10.1103/PhysRevD.77.103014
null
hep-ph astro-ph gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We write a covariant transport equation for the phonon excitations of a relativistic superfluid valid at small temperatures. The hydrodynamical equations for this system are derived from the effective field theory associated to the superfluid phonons. We describe how to construct the kinetic theory for the phonon quasiparticles using a relativistic generalization of the analogue model of gravity developed by Unruh. This gravity analogy relies on the equivalence between the action of a phonon field moving in a superfluid background with that of a boson propagating in a given curved space-time. Exploiting this analogy we obtain continuity equations for the phonon current, entropy and energy-momentum tensor in a covariant form, valid in any reference frame. Our aim is to shed light on some aspects of transport phenomena of relativistic superfluidity. In particular, we are interested in the low temperature regime of the color flavor locked phase, which is a color superconducting and superfluid phase of high density QCD that may be realized in the core of neutron stars.
[ { "created": "Mon, 4 Feb 2008 14:41:50 GMT", "version": "v1" } ]
2008-11-26
[ [ "Mannarelli", "Massimo", "" ], [ "Manuel", "Cristina", "" ] ]
We write a covariant transport equation for the phonon excitations of a relativistic superfluid valid at small temperatures. The hydrodynamical equations for this system are derived from the effective field theory associated to the superfluid phonons. We describe how to construct the kinetic theory for the phonon quasiparticles using a relativistic generalization of the analogue model of gravity developed by Unruh. This gravity analogy relies on the equivalence between the action of a phonon field moving in a superfluid background with that of a boson propagating in a given curved space-time. Exploiting this analogy we obtain continuity equations for the phonon current, entropy and energy-momentum tensor in a covariant form, valid in any reference frame. Our aim is to shed light on some aspects of transport phenomena of relativistic superfluidity. In particular, we are interested in the low temperature regime of the color flavor locked phase, which is a color superconducting and superfluid phase of high density QCD that may be realized in the core of neutron stars.
2205.09109
Marcos Rodriguez Cardoso
M. C. Rodriguez
Gauge bosons masses in the context of the Supersymmetric $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{N}$ Model
17 pages, 4 tables, 1 figure
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the boson masses and their mixing in the Minimal Supersymmetric $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{N}$ Model, and we will show all the numerical results are in agreement with actual current experimental limits.
[ { "created": "Wed, 18 May 2022 17:57:38 GMT", "version": "v1" }, { "created": "Fri, 10 Jun 2022 17:41:44 GMT", "version": "v2" }, { "created": "Thu, 11 May 2023 16:58:04 GMT", "version": "v3" }, { "created": "Sat, 11 Nov 2023 17:57:45 GMT", "version": "v4" } ]
2023-11-14
[ [ "Rodriguez", "M. C.", "" ] ]
We analyze the boson masses and their mixing in the Minimal Supersymmetric $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{N}$ Model, and we will show all the numerical results are in agreement with actual current experimental limits.
2108.01101
Pablo Escribano
Pablo Escribano, Martin Hirsch, Jacopo Nava, Avelino Vicente
Observable flavor violation from spontaneous lepton number breaking
32 pages, 5 figures, 2 tables; v2: Improved phenomenological analysis, Matches published version
null
10.1007/JHEP01(2022)098
IFIC/22-02
hep-ph
http://creativecommons.org/licenses/by/4.0/
We propose a simple model of spontaneous lepton number violation with potentially large flavor violating decays, including the possibility that majoron emitting decays, such as $\mu \to e \, J$, saturate the experimental bounds. In this model the majoron is a singlet-doublet admixture. It generates a type-I seesaw for neutrino masses and contains also a vector-like lepton. As a by-product, the model can explain the anomalous $(g-2)_{\mu}$ in parts of its parameter space, where one expects that the branching ratio of the Higgs to muons is changed with respect to Standard Model expectations. However, the explanation of the muon $g-2$ anomaly would lead to tension with recent astrophysical bounds on the majoron coupling to muons.
[ { "created": "Mon, 2 Aug 2021 18:01:03 GMT", "version": "v1" }, { "created": "Tue, 18 Jan 2022 08:59:04 GMT", "version": "v2" } ]
2022-02-09
[ [ "Escribano", "Pablo", "" ], [ "Hirsch", "Martin", "" ], [ "Nava", "Jacopo", "" ], [ "Vicente", "Avelino", "" ] ]
We propose a simple model of spontaneous lepton number violation with potentially large flavor violating decays, including the possibility that majoron emitting decays, such as $\mu \to e \, J$, saturate the experimental bounds. In this model the majoron is a singlet-doublet admixture. It generates a type-I seesaw for neutrino masses and contains also a vector-like lepton. As a by-product, the model can explain the anomalous $(g-2)_{\mu}$ in parts of its parameter space, where one expects that the branching ratio of the Higgs to muons is changed with respect to Standard Model expectations. However, the explanation of the muon $g-2$ anomaly would lead to tension with recent astrophysical bounds on the majoron coupling to muons.
hep-ph/9809433
Raju Venugopalan
Alex Krasnitz (University of the Algarve) and Raju Venugopalan (NBI)
Non-perturbative computation of gluon mini-jet production in nuclear collisions at very high energies
50 pages Latex, includes 7 figures, revised version, Nuclear Physics B, in press
Nucl.Phys. B557 (1999) 237
10.1016/S0550-3213(99)00366-1
NBI-98-21, UALG/TP/98-6
hep-ph hep-lat nucl-th
null
At very high energies, in the infinite momentum frame and in light cone gauge, a hard scale proportional to the high parton density arises in QCD. In an effective theory of QCD at small $x$, this scale is of order $\alpha_S\mu$, where $\mu$ is simply related to the gluon density at higher rapidities. The ab initio real time evolution of small $x$ modes in a nuclear collision can be described consistently in the classical effective theory and various features of interest can be studied non-perturbatively. In this paper, we discuss results from a real time lattice computation of the production of gluon jets at very high energies. At very large transverse momenta, $k_t\geq \mu$, our results match the predictions from pQCD based mini-jet calculations. Novel non-perturbative behaviour of the small $x$ modes is seen at smaller momenta $k_t\sim \alpha_S\mu$. Gauge invariant energy-energy correlators are used to estimate energy distributions evolving in proper time.
[ { "created": "Thu, 17 Sep 1998 14:13:35 GMT", "version": "v1" }, { "created": "Fri, 2 Jul 1999 04:45:43 GMT", "version": "v2" } ]
2009-10-31
[ [ "Krasnitz", "Alex", "", "University of the Algarve" ], [ "Venugopalan", "Raju", "", "NBI" ] ]
At very high energies, in the infinite momentum frame and in light cone gauge, a hard scale proportional to the high parton density arises in QCD. In an effective theory of QCD at small $x$, this scale is of order $\alpha_S\mu$, where $\mu$ is simply related to the gluon density at higher rapidities. The ab initio real time evolution of small $x$ modes in a nuclear collision can be described consistently in the classical effective theory and various features of interest can be studied non-perturbatively. In this paper, we discuss results from a real time lattice computation of the production of gluon jets at very high energies. At very large transverse momenta, $k_t\geq \mu$, our results match the predictions from pQCD based mini-jet calculations. Novel non-perturbative behaviour of the small $x$ modes is seen at smaller momenta $k_t\sim \alpha_S\mu$. Gauge invariant energy-energy correlators are used to estimate energy distributions evolving in proper time.
hep-ph/0212347
Valery Lyubovitskij
S. Cheedket (Tuebingen and Suranaree U.), V.E. Lyubovitskij (Tuebingen U.), Th. Gutsche (Tuebingen U.), Amand Faessler (Tuebingen U.), K. Pumsa-ard (Tuebingen U.) and Y. Yan (Suranaree U.)
Electromagnetic form factors of the baryon octet in the perturbative chiral quark model
15 pages, 6 figures, to be published in Eur. Phys. J. A
Eur.Phys.J. A20 (2004) 317-327
10.1140/epja/i2003-10165-4
null
hep-ph
null
We apply the perturbative chiral quark model at one loop to analyze the electromagnetic form factors of the baryon octet. The analytic expressions for baryon form factors, which are given in terms of fundamental parameters of low-energy pion-nucleon physics (weak pion decay constant, axial nucleon coupling, strong pion-nucleon form factor), and the numerical results for baryon magnetic moments, charge and magnetic radii are presented. Our results are in good agreement with experimental data.
[ { "created": "Mon, 23 Dec 2002 20:45:45 GMT", "version": "v1" }, { "created": "Mon, 23 Dec 2002 21:27:30 GMT", "version": "v2" }, { "created": "Thu, 12 Feb 2004 14:14:44 GMT", "version": "v3" } ]
2007-05-23
[ [ "Cheedket", "S.", "", "Tuebingen and Suranaree U." ], [ "Lyubovitskij", "V. E.", "", "Tuebingen\n U." ], [ "Gutsche", "Th.", "", "Tuebingen U." ], [ "Faessler", "Amand", "", "Tuebingen U." ], [ "Pumsa-ard", "K.", "", "Tuebingen U." ], [ "Yan", "Y.", "", "Suranaree U." ] ]
We apply the perturbative chiral quark model at one loop to analyze the electromagnetic form factors of the baryon octet. The analytic expressions for baryon form factors, which are given in terms of fundamental parameters of low-energy pion-nucleon physics (weak pion decay constant, axial nucleon coupling, strong pion-nucleon form factor), and the numerical results for baryon magnetic moments, charge and magnetic radii are presented. Our results are in good agreement with experimental data.