id
stringlengths
9
14
submitter
stringlengths
1
56
authors
stringlengths
5
7.68k
title
stringlengths
3
299
comments
stringlengths
1
1.15k
journal-ref
stringlengths
9
298
doi
stringlengths
12
97
report-no
stringlengths
3
341
categories
stringclasses
869 values
license
stringclasses
9 values
orig_abstract
stringlengths
16
2.44k
versions
listlengths
1
39
update_date
stringlengths
10
10
authors_parsed
listlengths
1
565
abstract
stringlengths
13
2.44k
0705.0565
Sachiko Takeuchi
Sachiko Takeuchi and Kiyotaka Shimizu
Lambda(1405) as a Resonance in the Baryon-Meson Scattering Coupled to the q^3 State in a Quark Model
16 pages and 7 figures
Phys.Rev.C76:035204,2007
10.1103/PhysRevC.76.035204
null
hep-ph
null
In order to describe Lambda(1405) as a resonance in the baryon-meson scattering, we have investigated q^3-q qbar scattering system with the flavor-singlet q^3 (0s)^2(0p) state (the Lambda^1 pole). The scattering is treated by the quark cluster model (QCM). The Lambda^1 pole is treated as a bound state embedded in the continuum. We found that the peak appears below the N Kbar threshold in the spin one half, isospin 0 channel even if the mass of the Lambda^1 pole is above the threshold. This peak disappears when the coupling to the Lambda^1 pole is switched off. To use the observed hadron mass in the kinetic part of QCM is also found to be important to reproduce a peak just below the N Kbar threshold.
[ { "created": "Fri, 4 May 2007 07:04:38 GMT", "version": "v1" } ]
2008-11-26
[ [ "Takeuchi", "Sachiko", "" ], [ "Shimizu", "Kiyotaka", "" ] ]
In order to describe Lambda(1405) as a resonance in the baryon-meson scattering, we have investigated q^3-q qbar scattering system with the flavor-singlet q^3 (0s)^2(0p) state (the Lambda^1 pole). The scattering is treated by the quark cluster model (QCM). The Lambda^1 pole is treated as a bound state embedded in the continuum. We found that the peak appears below the N Kbar threshold in the spin one half, isospin 0 channel even if the mass of the Lambda^1 pole is above the threshold. This peak disappears when the coupling to the Lambda^1 pole is switched off. To use the observed hadron mass in the kinetic part of QCM is also found to be important to reproduce a peak just below the N Kbar threshold.
hep-ph/0610304
Juan Jose Sanz-Cillero
J.J. Sanz-Cillero
Resonance Form-Factors: L8 Determination at Next-to-Leading Order in 1/NC
3 pages, 1 figure; proceedings of the IVth International Conference on Quarks and Nuclear Physics, Madrid, June 5-10 2006
null
null
null
hep-ph
null
This talk presents a systematic procedure for the computation of the SS-PP correlator beyond the large--NC limit. The present calculation is carried on within a perturbative 1/NC framework . By constraining the meson form-factors at leading order in 1/NC, one obtains a one-loop spectral function well behaved at short distances. The Weinberg sum-rules get modified, gaining an extra contribution suppressed by 1/NC. This leads to a prediction for the low energy chiral perturbation theory coupling L8^r(mu) at the one-loop level, i.e., up to next-to-leading order in 1/NC.
[ { "created": "Tue, 24 Oct 2006 06:00:31 GMT", "version": "v1" } ]
2007-05-23
[ [ "Sanz-Cillero", "J. J.", "" ] ]
This talk presents a systematic procedure for the computation of the SS-PP correlator beyond the large--NC limit. The present calculation is carried on within a perturbative 1/NC framework . By constraining the meson form-factors at leading order in 1/NC, one obtains a one-loop spectral function well behaved at short distances. The Weinberg sum-rules get modified, gaining an extra contribution suppressed by 1/NC. This leads to a prediction for the low energy chiral perturbation theory coupling L8^r(mu) at the one-loop level, i.e., up to next-to-leading order in 1/NC.
hep-ph/9704434
Eric S. Swanson
Eric S. Swanson and Adam P. Szczepaniak
Hybrid Decays
13 pages, 1 table, revtex
Phys.Rev. D56 (1997) 5692-5695
10.1103/PhysRevD.56.5692
null
hep-ph
null
The heavy quark expansion of Quantum Chromodynamics and the strong coupling flux tube picture of nonperturbative glue are employed to develop the phenomenology of hybrid meson decays. The decay mechanism explicitly couples gluonic degrees of freedom to the pair produced quarks and hence does not obey the well known, but model-dependent, selection rule which states that hybrids do not decay to pairs of L=0 mesons. However, the nonperturbative nature of gluonic excitations in the flux tube picture leads to a new selection rule: light hybrids do not decay to pairs of identical mesons. New features of the model are highlighted and partial widths are presented for several low lying hybrid states.
[ { "created": "Tue, 29 Apr 1997 13:51:03 GMT", "version": "v1" } ]
2016-09-06
[ [ "Swanson", "Eric S.", "" ], [ "Szczepaniak", "Adam P.", "" ] ]
The heavy quark expansion of Quantum Chromodynamics and the strong coupling flux tube picture of nonperturbative glue are employed to develop the phenomenology of hybrid meson decays. The decay mechanism explicitly couples gluonic degrees of freedom to the pair produced quarks and hence does not obey the well known, but model-dependent, selection rule which states that hybrids do not decay to pairs of L=0 mesons. However, the nonperturbative nature of gluonic excitations in the flux tube picture leads to a new selection rule: light hybrids do not decay to pairs of identical mesons. New features of the model are highlighted and partial widths are presented for several low lying hybrid states.
1011.2112
Lei Wang
Lei Wang, Xiao-Fang Han
Pseudoscalar boson and SM-like Higgs boson productions at LHC in simplest little Higgs model
15 pages, 6 figures. Accepted for publication in Phys. ReV. D
Phys.Rev.D82:095009,2010
10.1103/PhysRevD.82.095009
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the framework of the simplest little Higgs model (SLHM), we perform a comprehensive study for the pair productions of the pseudoscalar boson {\eta} and SM-like Higgs boson h at LHC, namely gg(b\bar{b})-> {\eta}{\eta}, gg(q\bar{q})-> {\eta}h and gg(b\bar{b})-> hh. These production processes provide a way to probe the couplings between Higgs bosons. We find that the cross section of gg-> {\eta}{\eta} always dominates over that of b\bar{b}-> {\eta}{\eta}. When the Higgs boson h which mediates these two processes is on-shell, their cross sections can reach several thousand $fb$ and several hundred $fb$, respectively. When the intermediate state h is off-shell, those two cross sections are reduced by two orders of magnitude, respectively. The cross sections of gg-> {\eta}h and q\bar{q}-> {\eta}h are about in the same order of magnitude, which can reach $\ord{(10^2fb)}$ for a light {\eta} boson. Besides, compared with the SM prediction, the cross section of a pair of SM-like Higgs bosons production at LHC can be enhanced sizably. Finally, we briefly discuss the observable signatures of {\eta}{\eta}, {\eta}h and hh at the LHC, respectively.
[ { "created": "Tue, 9 Nov 2010 15:14:57 GMT", "version": "v1" } ]
2010-12-23
[ [ "Wang", "Lei", "" ], [ "Han", "Xiao-Fang", "" ] ]
In the framework of the simplest little Higgs model (SLHM), we perform a comprehensive study for the pair productions of the pseudoscalar boson {\eta} and SM-like Higgs boson h at LHC, namely gg(b\bar{b})-> {\eta}{\eta}, gg(q\bar{q})-> {\eta}h and gg(b\bar{b})-> hh. These production processes provide a way to probe the couplings between Higgs bosons. We find that the cross section of gg-> {\eta}{\eta} always dominates over that of b\bar{b}-> {\eta}{\eta}. When the Higgs boson h which mediates these two processes is on-shell, their cross sections can reach several thousand $fb$ and several hundred $fb$, respectively. When the intermediate state h is off-shell, those two cross sections are reduced by two orders of magnitude, respectively. The cross sections of gg-> {\eta}h and q\bar{q}-> {\eta}h are about in the same order of magnitude, which can reach $\ord{(10^2fb)}$ for a light {\eta} boson. Besides, compared with the SM prediction, the cross section of a pair of SM-like Higgs bosons production at LHC can be enhanced sizably. Finally, we briefly discuss the observable signatures of {\eta}{\eta}, {\eta}h and hh at the LHC, respectively.
1704.04840
Kentaro Kojima
Kentaro Kojima, Kazunori Takenaga and Toshifumi Yamashita
The Standard Model Gauge Symmetry from Higher-Rank Unified Groups in Grand Gauge-Higgs Unification Models
34 pages, 1 figure, clarifications added in Sec. 6, published version
null
10.1007/JHEP06(2017)018
KYUSHU-HET-176
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study grand unified models in the five-dimensional space-time where the extra dimension is compactified on $S^1/Z_2$. The spontaneous breaking of unified gauge symmetries is achieved via vacuum expectation values of the extra-dimensional components of gauge fields. We derive one-loop effective potentials for the zero modes of the gauge fields in SU(7), SU(8), SO(10), and $E_6$ models. In each model, the rank of the residual gauge symmetry that respects the boundary condition imposed at the orbifold fixed points is higher than that of the standard model. We verify that the residual symmetry is broken to the standard model gauge symmetry at the global minima of the effective potential for certain sets of bulk fermion fields in each model.
[ { "created": "Mon, 17 Apr 2017 00:58:40 GMT", "version": "v1" }, { "created": "Mon, 19 Jun 2017 01:47:34 GMT", "version": "v2" } ]
2017-06-28
[ [ "Kojima", "Kentaro", "" ], [ "Takenaga", "Kazunori", "" ], [ "Yamashita", "Toshifumi", "" ] ]
We study grand unified models in the five-dimensional space-time where the extra dimension is compactified on $S^1/Z_2$. The spontaneous breaking of unified gauge symmetries is achieved via vacuum expectation values of the extra-dimensional components of gauge fields. We derive one-loop effective potentials for the zero modes of the gauge fields in SU(7), SU(8), SO(10), and $E_6$ models. In each model, the rank of the residual gauge symmetry that respects the boundary condition imposed at the orbifold fixed points is higher than that of the standard model. We verify that the residual symmetry is broken to the standard model gauge symmetry at the global minima of the effective potential for certain sets of bulk fermion fields in each model.
2005.06219
Peter Zeiler Skands
Nicholas Hunt-Smith and Peter Skands
String Fragmentation with a Time-Dependent Tension
v2: included predictions for strange baryons
null
10.1140/epjc/s10052-020-08654-9
MCNET-20-14, CoEPP-MN-20-4
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by recent theoretical arguments that expanding strings can be regarded as having a temperature that is inversely proportional to the proper time, tau, we investigate the consequences of adding a term proportional to 1/tau to the string tension in the Lund string-hadronization model. The lattice value for the tension, kappa0 ~ 0.18 GeV^2 ~ 0.9 GeV/fm, is then interpreted as the late-time/equilibrium limit. A generic prediction of this type of model is that early string breaks should be associated with higher strangeness (and baryon) fractions and higher fragmentation <pT> values. It should be possible to use archival ee data sets to provide model-independent constraints on this type of scenario, and we propose a few simple key measurements to do so.
[ { "created": "Wed, 13 May 2020 09:19:48 GMT", "version": "v1" }, { "created": "Mon, 16 Nov 2020 00:45:17 GMT", "version": "v2" } ]
2020-12-30
[ [ "Hunt-Smith", "Nicholas", "" ], [ "Skands", "Peter", "" ] ]
Motivated by recent theoretical arguments that expanding strings can be regarded as having a temperature that is inversely proportional to the proper time, tau, we investigate the consequences of adding a term proportional to 1/tau to the string tension in the Lund string-hadronization model. The lattice value for the tension, kappa0 ~ 0.18 GeV^2 ~ 0.9 GeV/fm, is then interpreted as the late-time/equilibrium limit. A generic prediction of this type of model is that early string breaks should be associated with higher strangeness (and baryon) fractions and higher fragmentation <pT> values. It should be possible to use archival ee data sets to provide model-independent constraints on this type of scenario, and we propose a few simple key measurements to do so.
1306.6420
Dmitri Kazakov
D.I.Kazakov
SUSY Phenomenology today
10 pages, 13 figures, PDFLatex, Talk at EW Rencontres de Moriond, 2013
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The review of the SUSY phenomenology today is given with the emphasis on generic properties of SUSY models, SUSY searches at the LHC and in astrophysics. Due to the absence of any definite SUSY signal at accelerators and other experiments, we describe the allowed regions in the MSSM and NMSSM parameter space and discuss the possibilities of SUSY manifestation in the near future.
[ { "created": "Thu, 27 Jun 2013 07:13:41 GMT", "version": "v1" } ]
2013-06-28
[ [ "Kazakov", "D. I.", "" ] ]
The review of the SUSY phenomenology today is given with the emphasis on generic properties of SUSY models, SUSY searches at the LHC and in astrophysics. Due to the absence of any definite SUSY signal at accelerators and other experiments, we describe the allowed regions in the MSSM and NMSSM parameter space and discuss the possibilities of SUSY manifestation in the near future.
hep-ph/0401169
Hyung Do Kim
Hyung Do Kim, Stuart Raby and Leslie Schradin
Quark Mass Textures and sin 2 beta
1+20 pages, 2 figures, JHEP3 class
Phys.Rev. D69 (2004) 092002
10.1103/PhysRevD.69.092002
OHSTPY-HEP-T-04-002
hep-ph
null
Recent precise measurements of sin 2 beta from the B-factories (BABAR and BELLE) and a better known strange quark mass from lattice QCD make precision tests of predictive texture models possible. The models tested include those hierarchical N-zero textures classified by Ramond, Roberts and Ross, as well as any other hierarchical matrix Ansatz with non-zero 12 = 21 and vanishing 11 and 13 elements. We calculate the maximally allowed value for sin 2 beta in these models and show that all the aforementioned models with vanishing 11 and 13 elements are ruled out at the 3 sigma level. While at present sin 2 beta and |Vub/Vcb| are equally good for testing N-zero texture models, in the near future the former will surpass the latter in constraining power.
[ { "created": "Thu, 22 Jan 2004 20:24:29 GMT", "version": "v1" } ]
2009-11-10
[ [ "Kim", "Hyung Do", "" ], [ "Raby", "Stuart", "" ], [ "Schradin", "Leslie", "" ] ]
Recent precise measurements of sin 2 beta from the B-factories (BABAR and BELLE) and a better known strange quark mass from lattice QCD make precision tests of predictive texture models possible. The models tested include those hierarchical N-zero textures classified by Ramond, Roberts and Ross, as well as any other hierarchical matrix Ansatz with non-zero 12 = 21 and vanishing 11 and 13 elements. We calculate the maximally allowed value for sin 2 beta in these models and show that all the aforementioned models with vanishing 11 and 13 elements are ruled out at the 3 sigma level. While at present sin 2 beta and |Vub/Vcb| are equally good for testing N-zero texture models, in the near future the former will surpass the latter in constraining power.
1401.2162
Muhammad Jamil Aslam
Ishtiaq Ahmed, M. Jamil Aslam and M. Ali Paracha
Effects of neutral $Z^{\prime}$ boson in $B_{s} \to \phi \ell^{+} \ell^{-}$ decay with polarized $\phi$ and the unpolarized and polarized $CP$ violation asymmetry
19 pages, 12 figures, A version close to the one accepted for publication in Physics Review D. Reference 59 is updated
Phys. Rev. D 89 (2014) 015006
10.1103/PhysRevD.89.015006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The effects of new neutral $Z^\prime$ boson in $B_{s}\to\phi\ell^{+}\ell^{-}$, when $\phi$ is longitudinal or transverse polarized, are studied. In addition, the implications of $Z^{\prime}$ boson on the unpolarized and polarized $CP$ violation asymmetries, with reference to lepton, are also presented. It is observed that the branching ratio with polarized $\phi$ are quite sensitive to the $Z^{\prime}$ contributions which are coming through the modification of Wilson coefficients $C^{eff}_{9}$ and $C_{10}$. Moreover, the off-diagonal elements of the chiral $Z^{\prime}$ couplings contain new weak phase $\phi_{sb}$ that provide a new source of $CP$ violation. Keeping in view that in the FCNC transitions the $CP$ violation asymmetries are highly suppressed in the SM, we have studied the unpolarized and polarized $CP$ violation asymmetries in $B_{s}\to\phi\ell^{+}\ell^{-}$ decays. Our results indicate that these $CP$ violation asymmetries are remarkably significant and can attribute the any new physics coming through the $Z^{\prime}$ boson. It is hoped that the accurate measurements of these asymmetries will not only help us to establish NP but will also give a chance to determine the precise values of the coupling parameters of the $Z^{\prime}$ boson.
[ { "created": "Sat, 4 Jan 2014 16:47:01 GMT", "version": "v1" }, { "created": "Fri, 13 Jun 2014 17:39:10 GMT", "version": "v2" } ]
2015-06-18
[ [ "Ahmed", "Ishtiaq", "" ], [ "Aslam", "M. Jamil", "" ], [ "Paracha", "M. Ali", "" ] ]
The effects of new neutral $Z^\prime$ boson in $B_{s}\to\phi\ell^{+}\ell^{-}$, when $\phi$ is longitudinal or transverse polarized, are studied. In addition, the implications of $Z^{\prime}$ boson on the unpolarized and polarized $CP$ violation asymmetries, with reference to lepton, are also presented. It is observed that the branching ratio with polarized $\phi$ are quite sensitive to the $Z^{\prime}$ contributions which are coming through the modification of Wilson coefficients $C^{eff}_{9}$ and $C_{10}$. Moreover, the off-diagonal elements of the chiral $Z^{\prime}$ couplings contain new weak phase $\phi_{sb}$ that provide a new source of $CP$ violation. Keeping in view that in the FCNC transitions the $CP$ violation asymmetries are highly suppressed in the SM, we have studied the unpolarized and polarized $CP$ violation asymmetries in $B_{s}\to\phi\ell^{+}\ell^{-}$ decays. Our results indicate that these $CP$ violation asymmetries are remarkably significant and can attribute the any new physics coming through the $Z^{\prime}$ boson. It is hoped that the accurate measurements of these asymmetries will not only help us to establish NP but will also give a chance to determine the precise values of the coupling parameters of the $Z^{\prime}$ boson.
hep-ph/0212048
Fernando Marchesano
D. Cremades, L.E. Ibanez and F. Marchesano
More about the Standard Model at Intersecting Branes
10 pages, Latex file, 7 figures. Contribution to the proceedings of SUSY-02, Hamburg
null
null
FTUAM-02/29 IFT-UAM/CSIC-02-48
hep-ph hep-th
null
Intersecting D-brane models seem to be one of the most promising avenues to embed the Standard Model physics within the string context. We review here different aspects of these models. Topics include the question of SUSY and quasi-SUSY in intersecting brane models, model-building, the brane recombination interpretation of the SM Higgs mechanism, Yukawa couplings, the lowering of the string scale and possible new Z's accessible to accelerators.
[ { "created": "Tue, 3 Dec 2002 15:21:09 GMT", "version": "v1" } ]
2007-05-23
[ [ "Cremades", "D.", "" ], [ "Ibanez", "L. E.", "" ], [ "Marchesano", "F.", "" ] ]
Intersecting D-brane models seem to be one of the most promising avenues to embed the Standard Model physics within the string context. We review here different aspects of these models. Topics include the question of SUSY and quasi-SUSY in intersecting brane models, model-building, the brane recombination interpretation of the SM Higgs mechanism, Yukawa couplings, the lowering of the string scale and possible new Z's accessible to accelerators.
hep-ph/9706242
Ray Volkas
R. Foot and R. R. Volkas
How neutrino oscillations can induce an effective neutrino number of less than 3 during Big Bang Nucleosynthesis
22 pages, LaTeX, 2 figures
Phys.Rev.D56:6653-6664,1997; Erratum-ibid.D59:029901,1999
10.1103/PhysRevD.56.6653 10.1103/PhysRevD.59.029901
UM-P-97/31
hep-ph astro-ph
null
Ordinary-sterile neutrino oscillations can generate significant neutrino asymmetry in the early Universe. In this paper we extend this work by computing the evolution of neutrino asymmetries and light element abundances during the Big Bang Nucleosynthesis (BBN) epoch. We show that a significant electron-neutrino asymmetry can be generated in a way that is approximately independent of the oscillation parameters $\delta m^2$ and $\sin^2 2\theta$ for a range of parameters in an interesting class of models. The numerical value of the asymmetry leads to the prediction that the effective number of neutrino flavours during BBN is either about 2.5 or 3.4 depending on the sign of the asymmetry. Interestingly, one class of primordial deuterium abundance data favours an effective number of neutrino flavours during the epoch of BBN of less than 3.
[ { "created": "Wed, 4 Jun 1997 06:33:23 GMT", "version": "v1" } ]
2014-11-17
[ [ "Foot", "R.", "" ], [ "Volkas", "R. R.", "" ] ]
Ordinary-sterile neutrino oscillations can generate significant neutrino asymmetry in the early Universe. In this paper we extend this work by computing the evolution of neutrino asymmetries and light element abundances during the Big Bang Nucleosynthesis (BBN) epoch. We show that a significant electron-neutrino asymmetry can be generated in a way that is approximately independent of the oscillation parameters $\delta m^2$ and $\sin^2 2\theta$ for a range of parameters in an interesting class of models. The numerical value of the asymmetry leads to the prediction that the effective number of neutrino flavours during BBN is either about 2.5 or 3.4 depending on the sign of the asymmetry. Interestingly, one class of primordial deuterium abundance data favours an effective number of neutrino flavours during the epoch of BBN of less than 3.
hep-ph/0501033
Per Osland
B. K. Gjelsten, D. J. Miller, P. Osland
Measurement of the Gluino Mass via Cascade Decays for SPS 1a
40 pages; extended discussion of errors
JHEP 0506:015,2005
10.1088/1126-6708/2005/06/015
null
hep-ph hep-ex
null
If R-parity conserving supersymmetry is realised with masses below the TeV scale, sparticles will be produced and decay in cascades at the LHC. In the case of a neutral LSP, which will not be detected, decay chains cannot be fully reconstructed, complicating the mass determination of the new particles. In this paper we extend the method of obtaining masses from kinematical endpoints to include a gluino at the head of a five-sparticle decay chain. This represents a non-trivial extension of the corresponding method for the squark decay chain. We calculate the endpoints of the new distributions and assess their applicability by examining the theoretical distributions for a variety of mass scenarios. The precision with which the gluino mass can be determined by this method is investigated for the mSUGRA point SPS 1a. Finally we estimate the improvement obtained from adding a Linear Collider measurement of the LSP mass.
[ { "created": "Thu, 6 Jan 2005 12:47:53 GMT", "version": "v1" }, { "created": "Tue, 14 Jun 2005 13:10:15 GMT", "version": "v2" } ]
2009-11-11
[ [ "Gjelsten", "B. K.", "" ], [ "Miller", "D. J.", "" ], [ "Osland", "P.", "" ] ]
If R-parity conserving supersymmetry is realised with masses below the TeV scale, sparticles will be produced and decay in cascades at the LHC. In the case of a neutral LSP, which will not be detected, decay chains cannot be fully reconstructed, complicating the mass determination of the new particles. In this paper we extend the method of obtaining masses from kinematical endpoints to include a gluino at the head of a five-sparticle decay chain. This represents a non-trivial extension of the corresponding method for the squark decay chain. We calculate the endpoints of the new distributions and assess their applicability by examining the theoretical distributions for a variety of mass scenarios. The precision with which the gluino mass can be determined by this method is investigated for the mSUGRA point SPS 1a. Finally we estimate the improvement obtained from adding a Linear Collider measurement of the LSP mass.
1507.01570
Maria Vittoria Garzelli
M.V. Garzelli, S. Moch, G. Sigl
Lepton fluxes from atmospheric charm revisited
40 pages, 24 figures
JHEP 1510 (2015) 115
10.1007/JHEP10(2015)115
DESY 15-107, MITP/15-049
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We update predictions for lepton fluxes from the hadroproduction of charm quarks in the scattering of primary cosmic rays with the Earth's atmosphere. The calculation of charm-pair hadroproduction applies the latest results from perturbative QCD through next-to-next-to-leading order and modern parton distributions, together with estimates on various sources of uncertainties. Our predictions for the lepton fluxes turn out to be compatible, within the uncertainty band, with recent results in the literature. However, by taking into account contributions neglected in previous works, our total uncertainties are much larger. The predictions are crucial for the interpretation of results from neutrino experiments like IceCube, when disentangling signals of neutrinos of astrophysical origin from the atmospheric background.
[ { "created": "Mon, 6 Jul 2015 19:29:12 GMT", "version": "v1" } ]
2016-01-01
[ [ "Garzelli", "M. V.", "" ], [ "Moch", "S.", "" ], [ "Sigl", "G.", "" ] ]
We update predictions for lepton fluxes from the hadroproduction of charm quarks in the scattering of primary cosmic rays with the Earth's atmosphere. The calculation of charm-pair hadroproduction applies the latest results from perturbative QCD through next-to-next-to-leading order and modern parton distributions, together with estimates on various sources of uncertainties. Our predictions for the lepton fluxes turn out to be compatible, within the uncertainty band, with recent results in the literature. However, by taking into account contributions neglected in previous works, our total uncertainties are much larger. The predictions are crucial for the interpretation of results from neutrino experiments like IceCube, when disentangling signals of neutrinos of astrophysical origin from the atmospheric background.
hep-ph/9610252
Ann E. Nelson
Andrew G. Cohen, David B. Kaplan, Francois Lepeintre and Ann E. Nelson
B-factory Physics from Effective Supersymmetry
5 pages, 2 figures, revtex, epsf
Phys.Rev.Lett. 78 (1997) 2300-2303
10.1103/PhysRevLett.78.2300
UW/PT-96/22, DOE/ER/40561290-INT96-148, BUHEP-96-38
hep-ph hep-ex
null
We discuss how to extract non-Standard Model effects from B-factory phenomenology. We then analyze the prospects for uncovering evidence for Effective Supersymmetry, a class of supersymmetric models which naturally suppress flavor changing neutral currents and electric dipole moments without squark universality or small CP violating phases, in experiments at BaBar, BELLE, HERA-B, CDF/D0 and LHC-B.
[ { "created": "Sat, 5 Oct 1996 00:14:33 GMT", "version": "v1" }, { "created": "Mon, 7 Oct 1996 00:50:45 GMT", "version": "v2" }, { "created": "Wed, 19 Feb 1997 00:35:00 GMT", "version": "v3" } ]
2009-10-28
[ [ "Cohen", "Andrew G.", "" ], [ "Kaplan", "David B.", "" ], [ "Lepeintre", "Francois", "" ], [ "Nelson", "Ann E.", "" ] ]
We discuss how to extract non-Standard Model effects from B-factory phenomenology. We then analyze the prospects for uncovering evidence for Effective Supersymmetry, a class of supersymmetric models which naturally suppress flavor changing neutral currents and electric dipole moments without squark universality or small CP violating phases, in experiments at BaBar, BELLE, HERA-B, CDF/D0 and LHC-B.
1104.3496
Jos\'e Francisco Zurita
Ezequiel Alvarez, Estefania Coluccio Leskow and Jos\'e Zurita
Collider Bounds on Lee-Wick Higgs Bosons
26 pages, 5 figures, matches version published by PRD
Phys.Rev.D83:115024,2011
10.1103/PhysRevD.83.115024
ZU-TH 06/11
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the constraints on the Lee-Wick Higgs sector arising from direct collider searches. We work in an effective-field theory framework, where all of the Lee-Wick partners are integrated out, with the sole exception of the Lee-Wick Higgs bosons. The resulting theory is a two-Higgs doublet model where the second doublet has wrong-sign kinetic and mass terms. We include the bounds coming from direct Higgs searches at both LEP and Tevatron using the code HiggsBounds, and show the currently excluded parameter space. We also analyze the prospects of LHC Run-I, finding that with a total integrated luminosity of 5 fb $^{-1}$ and a center-of-mass energy of 7 TeV, most of the parameter space for the SM-like CP-even Higgs will be probed.
[ { "created": "Mon, 18 Apr 2011 14:32:28 GMT", "version": "v1" }, { "created": "Sat, 23 Jul 2011 18:51:26 GMT", "version": "v2" } ]
2011-07-26
[ [ "Alvarez", "Ezequiel", "" ], [ "Leskow", "Estefania Coluccio", "" ], [ "Zurita", "José", "" ] ]
We study the constraints on the Lee-Wick Higgs sector arising from direct collider searches. We work in an effective-field theory framework, where all of the Lee-Wick partners are integrated out, with the sole exception of the Lee-Wick Higgs bosons. The resulting theory is a two-Higgs doublet model where the second doublet has wrong-sign kinetic and mass terms. We include the bounds coming from direct Higgs searches at both LEP and Tevatron using the code HiggsBounds, and show the currently excluded parameter space. We also analyze the prospects of LHC Run-I, finding that with a total integrated luminosity of 5 fb $^{-1}$ and a center-of-mass energy of 7 TeV, most of the parameter space for the SM-like CP-even Higgs will be probed.
hep-ph/0105153
Ngee-Pong Chang
Ngee-Pong Chang
Oscillations of Faster than Light Majorana Neutrinos: A Causal Field Theory
12 pages, no figures
Mod.Phys.Lett. A16 (2001) 2129-2142
10.1142/S021773230100562X
CCNY-HEP-01-11
hep-ph hep-th
null
In this paper, we carry out the canonical quantization of the field theory of an interacting tachyonic Majorana neutrino. We show how micro-causality is preserved in the physical scattering matrix elements between the in and out vacua. The phenomenology of this radical proposal is nevertheless compatible with normal timelike oscillations.
[ { "created": "Wed, 16 May 2001 02:44:22 GMT", "version": "v1" } ]
2009-11-07
[ [ "Chang", "Ngee-Pong", "" ] ]
In this paper, we carry out the canonical quantization of the field theory of an interacting tachyonic Majorana neutrino. We show how micro-causality is preserved in the physical scattering matrix elements between the in and out vacua. The phenomenology of this radical proposal is nevertheless compatible with normal timelike oscillations.
1803.11009
Jo\~ao Tiago Neves Penedo
J. T. Penedo, S. T. Petcov, A. V. Titov
Neutrino Mixing and Leptonic CP Violation from $S_4$ and Generalised CP Symmetries
Poster presented at NuPhys2017 (London, 20-22 December 2017). 4 pages, LaTeX, 2 pdf figures
null
null
NuPhys2017-Penedo
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a class of models of neutrino mixing with $S_4$ flavour symmetry and generalised CP symmetry, broken to $Z_2$ and $Z_2 \times {\rm CP}$ residual symmetries in the charged lepton and neutrino sectors, respectively. In this scheme, and up to discrete ambiguities, the neutrino mixing matrix is determined by two angles and one phase. We classify the phenomenologically viable mixing patterns, deriving predictions for the Dirac and Majorana CPV phases and for the effective Majorana mass in neutrinoless double beta decay.
[ { "created": "Thu, 29 Mar 2018 11:11:53 GMT", "version": "v1" } ]
2018-03-30
[ [ "Penedo", "J. T.", "" ], [ "Petcov", "S. T.", "" ], [ "Titov", "A. V.", "" ] ]
We consider a class of models of neutrino mixing with $S_4$ flavour symmetry and generalised CP symmetry, broken to $Z_2$ and $Z_2 \times {\rm CP}$ residual symmetries in the charged lepton and neutrino sectors, respectively. In this scheme, and up to discrete ambiguities, the neutrino mixing matrix is determined by two angles and one phase. We classify the phenomenologically viable mixing patterns, deriving predictions for the Dirac and Majorana CPV phases and for the effective Majorana mass in neutrinoless double beta decay.
hep-ph/0503007
Zhi-Gang Wang
Zhi-Gang Wang (NCEPU), Shao-Long Wan (USTC), Wei-Min Yang (USTC)
Magnetic moment of the pentaquark $\Theta^+(1540)$ as diquark-diquark-antiquark state with QCD sum rules
17 pages, 4 figures, unifing hep-ph/0503007 with hep-ph/0503073 into one article, input parameters changed slightly, add more discussions
Eur.Phys.J.C45:201-209,2006
10.1140/epjc/s2005-02400-1
null
hep-ph
null
In this article, we study the magnetic moment of the pentaquark state $ \Theta^+(1540)$ as diquark-diquark-antiquark ($[ud][ud]\bar{s}$) state with the QCD sum rules in the external weak electromagnetic field (EFSR) and the light-cone QCD sum rules (LCSR) respectively. The numerical results indicate the magnetic moment is about $\mu_{\Theta^+}=-(0.11\pm 0.02)\mu_N$ for the EFSR and $\mu_{\Theta^+}\approx-(0.1-0.5)\mu_N$ for the LCSR. As the values obtained from the EFSR are more stable than the corresponding ones from the LCSR, $\mu_{\Theta^+}=-(0.11\pm 0.02)\mu_N$ is more reliable.
[ { "created": "Tue, 1 Mar 2005 12:25:43 GMT", "version": "v1" }, { "created": "Thu, 17 Mar 2005 02:53:40 GMT", "version": "v2" }, { "created": "Thu, 9 Jun 2005 13:06:57 GMT", "version": "v3" }, { "created": "Mon, 27 Jun 2005 07:57:41 GMT", "version": "v4" } ]
2009-01-07
[ [ "Wang", "Zhi-Gang", "", "NCEPU" ], [ "Wan", "Shao-Long", "", "USTC" ], [ "Yang", "Wei-Min", "", "USTC" ] ]
In this article, we study the magnetic moment of the pentaquark state $ \Theta^+(1540)$ as diquark-diquark-antiquark ($[ud][ud]\bar{s}$) state with the QCD sum rules in the external weak electromagnetic field (EFSR) and the light-cone QCD sum rules (LCSR) respectively. The numerical results indicate the magnetic moment is about $\mu_{\Theta^+}=-(0.11\pm 0.02)\mu_N$ for the EFSR and $\mu_{\Theta^+}\approx-(0.1-0.5)\mu_N$ for the LCSR. As the values obtained from the EFSR are more stable than the corresponding ones from the LCSR, $\mu_{\Theta^+}=-(0.11\pm 0.02)\mu_N$ is more reliable.
1202.3431
Joachim Kopp
Carlos A. Arguelles (Pontificia Universidad Catolica del Peru and Fermilab) and Joachim Kopp (Fermilab)
Sterile neutrinos and indirect dark matter searches in IceCube
13 pages, 5 figures; v2: minor corrections and improvements to numerical results, added section about dependence of IceCube limits on sterile neutrino parameters; v3: minor clarifications and additional references, matches published version
JCAP 07 (2012) 016
10.1088/1475-7516/2012/07/016
FERMILAB-PUB-12-038-T
hep-ph astro-ph.SR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If light sterile neutrinos exist and mix with the active neutrino flavors, this mixing will affect the propagation of high-energy neutrinos from dark matter annihilation in the Sun. In particular, new Mikheyev-Smirnov-Wolfenstein resonances can occur, leading to almost complete conversion of some active neutrino flavors into sterile states. We demonstrate how this can weaken IceCube limits on neutrino capture and annihilation in the Sun and how potential future conflicts between IceCube constraints and direct detection or collider data might be resolved by invoking sterile neutrinos. We also point out that, if the dark matter--nucleon scattering cross section and the allowed annihilation channels are precisely measured in direct detection and collider experiments in the future, IceCube can be used to constrain sterile neutrino models using neutrinos from the dark matter annihilation.
[ { "created": "Wed, 15 Feb 2012 20:55:06 GMT", "version": "v1" }, { "created": "Wed, 28 Mar 2012 16:52:24 GMT", "version": "v2" }, { "created": "Fri, 6 Jul 2012 13:34:19 GMT", "version": "v3" } ]
2012-07-13
[ [ "Arguelles", "Carlos A.", "", "Pontificia Universidad Catolica del Peru and\n Fermilab" ], [ "Kopp", "Joachim", "", "Fermilab" ] ]
If light sterile neutrinos exist and mix with the active neutrino flavors, this mixing will affect the propagation of high-energy neutrinos from dark matter annihilation in the Sun. In particular, new Mikheyev-Smirnov-Wolfenstein resonances can occur, leading to almost complete conversion of some active neutrino flavors into sterile states. We demonstrate how this can weaken IceCube limits on neutrino capture and annihilation in the Sun and how potential future conflicts between IceCube constraints and direct detection or collider data might be resolved by invoking sterile neutrinos. We also point out that, if the dark matter--nucleon scattering cross section and the allowed annihilation channels are precisely measured in direct detection and collider experiments in the future, IceCube can be used to constrain sterile neutrino models using neutrinos from the dark matter annihilation.
1603.06130
Lukas Mitzka
Lukas Mitzka and Werner Porod
Reinterpretation of ATLAS 8 TeV searches for Natural SUSY with a $R$-Sneutrino LSP
27 pages, 9 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The data obtained by the LHC collaborations clearly show that supersymmetric models are not realized in nature in a vanilla form and that in particular strongly interacting supersymmetric particles are most likely heavier than expected. An exception are the partners of the third generation quarks, which also play a dominant role in the breaking of the electroweak symmetry. We consider here an extended class of so-called `natural supersymmetric models' where we allow for a sneutrino as the lightest supersymmetric particle as it appears for example in left-right symmetric models and/or models where supersymmetry is explained via an inverse seesaw mechanism. We evaluate how much existing ATLAS data constrain such scenarios and obtain roughly a bound of 300 GeV on the charginos if the sneutrinos are lighter than about 120 GeV. For the stop we find that only masses up to 300 GeV are excluded independent of the mixing angle. For larger values the exclusion depends on the detail of the scenario and if the mass exceeds 800 GeV no bound is obtained.
[ { "created": "Sat, 19 Mar 2016 18:54:34 GMT", "version": "v1" } ]
2016-03-22
[ [ "Mitzka", "Lukas", "" ], [ "Porod", "Werner", "" ] ]
The data obtained by the LHC collaborations clearly show that supersymmetric models are not realized in nature in a vanilla form and that in particular strongly interacting supersymmetric particles are most likely heavier than expected. An exception are the partners of the third generation quarks, which also play a dominant role in the breaking of the electroweak symmetry. We consider here an extended class of so-called `natural supersymmetric models' where we allow for a sneutrino as the lightest supersymmetric particle as it appears for example in left-right symmetric models and/or models where supersymmetry is explained via an inverse seesaw mechanism. We evaluate how much existing ATLAS data constrain such scenarios and obtain roughly a bound of 300 GeV on the charginos if the sneutrinos are lighter than about 120 GeV. For the stop we find that only masses up to 300 GeV are excluded independent of the mixing angle. For larger values the exclusion depends on the detail of the scenario and if the mass exceeds 800 GeV no bound is obtained.
0806.4799
Yuji Sakai
Yuji Sakai, Kouji Kashiwa, Hiroaki Kouno, Masayuki Matsuzaki, and Masanobu Yahiro
Vector-type four-quark interaction and its impact on QCD phase structure
8 pages, 11 figures
Phys.Rev.D78:076007,2008
10.1103/PhysRevD.78.076007
SAGA-HE-244-08
hep-ph hep-lat hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Effects of the vector-type four-quark interaction on QCD phase structure are investigated in the imaginary chemical potential region, by using the Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model with the extended Z3 symmetry. In the course to this end, we clarify analytically the Roberge-Weiss periodicity and symmetry properties of various quantities under the existence of a vector-type four-quark interaction. In the imaginary chemical potential region, the chiral condensate and the quark number density are sensitive to the strength of the interaction. Based on this result, we propose a possibility to determine the strength of the vector-type interaction, which largely affects QCD phase structure in the real chemical potential region, by comparing the results of lattice simulations and effective model calculations in the imaginary chemical potential region.
[ { "created": "Mon, 30 Jun 2008 04:27:18 GMT", "version": "v1" } ]
2008-11-26
[ [ "Sakai", "Yuji", "" ], [ "Kashiwa", "Kouji", "" ], [ "Kouno", "Hiroaki", "" ], [ "Matsuzaki", "Masayuki", "" ], [ "Yahiro", "Masanobu", "" ] ]
Effects of the vector-type four-quark interaction on QCD phase structure are investigated in the imaginary chemical potential region, by using the Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model with the extended Z3 symmetry. In the course to this end, we clarify analytically the Roberge-Weiss periodicity and symmetry properties of various quantities under the existence of a vector-type four-quark interaction. In the imaginary chemical potential region, the chiral condensate and the quark number density are sensitive to the strength of the interaction. Based on this result, we propose a possibility to determine the strength of the vector-type interaction, which largely affects QCD phase structure in the real chemical potential region, by comparing the results of lattice simulations and effective model calculations in the imaginary chemical potential region.
1311.0040
Jakub Scholtz
Ann E. Nelson and Jakub Scholtz
Heavy Flavor & Dark Sector
27 pages, 10 figures
Phys. Rev. D 91, 014009 (2015)
10.1103/PhysRevD.91.014009
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider some contributions to rare processes in $B$ meson decays from a Dark Sector containing 2 light unstable scalars, with large couplings to each other and small mixings with Standard Model Higgs scalars. We show that existing constraints allow for an exotic contribution to high multiplicity final states with a branching fraction as large as $\mathcal{O}(10^{-4})$, and that exotic particles could appear as narrow resonances or long lived particles which are mainly found in high multiplicity final states from $B$ decays.
[ { "created": "Thu, 31 Oct 2013 21:25:49 GMT", "version": "v1" } ]
2015-01-14
[ [ "Nelson", "Ann E.", "" ], [ "Scholtz", "Jakub", "" ] ]
We consider some contributions to rare processes in $B$ meson decays from a Dark Sector containing 2 light unstable scalars, with large couplings to each other and small mixings with Standard Model Higgs scalars. We show that existing constraints allow for an exotic contribution to high multiplicity final states with a branching fraction as large as $\mathcal{O}(10^{-4})$, and that exotic particles could appear as narrow resonances or long lived particles which are mainly found in high multiplicity final states from $B$ decays.
1307.3508
Alan D. Martin
E.G. de Oliveira, A.D. Martin, M.G. Ryskin and A.G. Shuvaev
Treatment of heavy quarks in QCD
14 pages, 3 figures, references updated, version to be published in EPJC
null
10.1140/epjc/s10052-013-2616-2
IPPP/13/53, DCPT/13/106
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that to correctly describe the effects of the heavy-quark mass, m_h, in DGLAP evolution, it is necessary to work in the so-called `physical' scheme. In this way, we automatically obtain a smooth transition through the heavy-quark thresholds. Moreover, we show that to obtain NLO accuracy, it is sufficient to account for the heavy-quark mass, m_h, just in the LO (one-loop) splitting function. The use of the MS-bar factorisation scheme is not appropriate, since at NLO we deal with a mixture of quarks and gluon (that is, the mass of the heavy parton is not well-defined). The formulae for the explicit m_h dependence of the splitting functions, and for alpha_s, are presented.
[ { "created": "Fri, 12 Jul 2013 16:39:15 GMT", "version": "v1" }, { "created": "Wed, 9 Oct 2013 09:55:01 GMT", "version": "v2" } ]
2015-06-16
[ [ "de Oliveira", "E. G.", "" ], [ "Martin", "A. D.", "" ], [ "Ryskin", "M. G.", "" ], [ "Shuvaev", "A. G.", "" ] ]
We show that to correctly describe the effects of the heavy-quark mass, m_h, in DGLAP evolution, it is necessary to work in the so-called `physical' scheme. In this way, we automatically obtain a smooth transition through the heavy-quark thresholds. Moreover, we show that to obtain NLO accuracy, it is sufficient to account for the heavy-quark mass, m_h, just in the LO (one-loop) splitting function. The use of the MS-bar factorisation scheme is not appropriate, since at NLO we deal with a mixture of quarks and gluon (that is, the mass of the heavy parton is not well-defined). The formulae for the explicit m_h dependence of the splitting functions, and for alpha_s, are presented.
2405.12943
Yi Chen
Yi Chen, Yang Li, C\'edric Lorc\'e, Qun Wang
The nucleon axial radius
6 pages, 3 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We present a systematic study of the relativistic axial-vector four-current distributions inside a nucleon. We show in particular that the slope of the axial form factor $G_A(Q^2)$ in the forward limit -- conventionally denoted as $R^2_A$ in the literature -- does not represent the three-dimensional mean-square axial radius in the Breit frame, but corresponds instead to a contribution to the mean-square spin radius. We derive explicit expressions for the latter in different frames and find in general additional contributions that depend on both the nucleon mass and the forward values of the axial-vector form factors $G_A(0)$ and $G_P(0)$.
[ { "created": "Tue, 21 May 2024 17:16:19 GMT", "version": "v1" } ]
2024-05-22
[ [ "Chen", "Yi", "" ], [ "Li", "Yang", "" ], [ "Lorcé", "Cédric", "" ], [ "Wang", "Qun", "" ] ]
We present a systematic study of the relativistic axial-vector four-current distributions inside a nucleon. We show in particular that the slope of the axial form factor $G_A(Q^2)$ in the forward limit -- conventionally denoted as $R^2_A$ in the literature -- does not represent the three-dimensional mean-square axial radius in the Breit frame, but corresponds instead to a contribution to the mean-square spin radius. We derive explicit expressions for the latter in different frames and find in general additional contributions that depend on both the nucleon mass and the forward values of the axial-vector form factors $G_A(0)$ and $G_P(0)$.
1707.07266
Kazuhiro Watanabe
Yan-Qing Ma, Raju Venugopalan, Kazuhiro Watanabe, Hong-Fei Zhang
$\psi(2S)$ versus $J/\psi$ suppression in proton-nucleus collisions from factorization violating soft color exchanges
16 pages, 12 figures. v2: version accepted for publication in PRC
Phys. Rev. C 97, 014909 (2018)
10.1103/PhysRevC.97.014909
JLAB-THY-17-2528
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We argue that the large suppression of the $\psi(2S)$ inclusive cross-section relative to the $J/\psi$ inclusive cross-section in proton-nucleus (p+A) collisions can be attributed to factorization breaking effects in the formation of quarkonium. These factorization breaking effects arise from soft color exchanges between charm-anticharm pairs undergoing hadronization and comoving partons that are long-lived on time scales of quarkonium formation. We compute the short distance pair production of heavy quarks in the Color Glass Condensate (CGC) effective field theory and employ an improved Color Evaporation model (ICEM) to describe their hadronization into quarkonium at large distances. The combined CGC+ICEM model provides a quantitative description of $J/\psi$ and $\psi(2S)$ data in proton-proton (p+p) collisions from both RHIC and the LHC. Factorization breaking effects in hadronization, due to additional parton comovers in the nucleus, are introduced heuristically by imposing a cutoff $\Lambda$, representing the momentum kick from soft color exchanges, in the ICEM model. Such soft exchanges have no perceptible effect on $J/\psi$ suppression in p+A collisions. In contrast, the interplay of the physics of these soft exchanges at large distances, with the physics of semi-hard rescattering at short distances, causes a significant additional suppression of $\psi(2S)$ yields relative to that of the $J/\psi$. A good fit of all RHIC and LHC $J/\psi$ and $\psi(2S)$ data, for transverse momenta $P_\perp\leq 5$ GeV in p+p and p+A collisions, is obtained for $\Lambda\sim 10$ MeV.
[ { "created": "Sun, 23 Jul 2017 08:24:00 GMT", "version": "v1" }, { "created": "Thu, 1 Feb 2018 02:36:28 GMT", "version": "v2" } ]
2018-02-02
[ [ "Ma", "Yan-Qing", "" ], [ "Venugopalan", "Raju", "" ], [ "Watanabe", "Kazuhiro", "" ], [ "Zhang", "Hong-Fei", "" ] ]
We argue that the large suppression of the $\psi(2S)$ inclusive cross-section relative to the $J/\psi$ inclusive cross-section in proton-nucleus (p+A) collisions can be attributed to factorization breaking effects in the formation of quarkonium. These factorization breaking effects arise from soft color exchanges between charm-anticharm pairs undergoing hadronization and comoving partons that are long-lived on time scales of quarkonium formation. We compute the short distance pair production of heavy quarks in the Color Glass Condensate (CGC) effective field theory and employ an improved Color Evaporation model (ICEM) to describe their hadronization into quarkonium at large distances. The combined CGC+ICEM model provides a quantitative description of $J/\psi$ and $\psi(2S)$ data in proton-proton (p+p) collisions from both RHIC and the LHC. Factorization breaking effects in hadronization, due to additional parton comovers in the nucleus, are introduced heuristically by imposing a cutoff $\Lambda$, representing the momentum kick from soft color exchanges, in the ICEM model. Such soft exchanges have no perceptible effect on $J/\psi$ suppression in p+A collisions. In contrast, the interplay of the physics of these soft exchanges at large distances, with the physics of semi-hard rescattering at short distances, causes a significant additional suppression of $\psi(2S)$ yields relative to that of the $J/\psi$. A good fit of all RHIC and LHC $J/\psi$ and $\psi(2S)$ data, for transverse momenta $P_\perp\leq 5$ GeV in p+p and p+A collisions, is obtained for $\Lambda\sim 10$ MeV.
hep-ph/9412249
Arnd Leike
K. Ko{\l}odziej, A. Leike, R. R\"uckl
Production Mechanisms for $B_c$ Mesons in Photon--Photon Collisions
10 pages Latex, 6 postscript figures (included by epsf)
Phys.Lett.B348:219-225,1995
10.1016/0370-2693(95)00121-Z
MPI-PhT/94-84, LMU-23/94
hep-ph
null
Using photon-photon collisions as a particularly transparent study case we investigate the production mechanisms for $B_c$ mesons. In nonrelativistic approximation and to $O(\alpha^2\alpha_s^2)$ it is shown that recombination of $\bar{b}$- and $c$-quarks dominates by far over $\bar{b}$ and $c$ fragmentation. This dominance persists up to the highest accessible transverse momenta and leads to distributions in energy which differ completely from the spectra expected on the basis of the fragmentation functions. For processes in which a $b \bar{b}$-pair is radiated from a primary $c$-quark, the fragmentation description is found to be inadequate. We anticipate important implications of these results for hadronic production of heavy quark resonances. Using realistic photon spectra we predict two-photon production rates for $B_c$ and $B_c^*$ at present and future $e^+e^-$-machines.
[ { "created": "Tue, 6 Dec 1994 16:56:19 GMT", "version": "v1" } ]
2011-01-25
[ [ "Kołodziej", "K.", "" ], [ "Leike", "A.", "" ], [ "Rückl", "R.", "" ] ]
Using photon-photon collisions as a particularly transparent study case we investigate the production mechanisms for $B_c$ mesons. In nonrelativistic approximation and to $O(\alpha^2\alpha_s^2)$ it is shown that recombination of $\bar{b}$- and $c$-quarks dominates by far over $\bar{b}$ and $c$ fragmentation. This dominance persists up to the highest accessible transverse momenta and leads to distributions in energy which differ completely from the spectra expected on the basis of the fragmentation functions. For processes in which a $b \bar{b}$-pair is radiated from a primary $c$-quark, the fragmentation description is found to be inadequate. We anticipate important implications of these results for hadronic production of heavy quark resonances. Using realistic photon spectra we predict two-photon production rates for $B_c$ and $B_c^*$ at present and future $e^+e^-$-machines.
1908.00207
Masaki Yamada
Ayuki Kamada, Masaki Yamada, Tsutomu T. Yanagida
Unification for the Darkly Charged Dark Matter
6 pages, 2 figures
Phys. Rev. D 102, 015012 (2020)
10.1103/PhysRevD.102.015012
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We provide a simple UV theory for a Dirac dark matter with a massless Abelian gauge boson. We introduce a single fermion transforming as the $\bf{16}$ representation in the SO(10)$'$ gauge group, which is assumed to be spontaneously broken to SU(5)$'\times$U(1)$'$. The SU(5)$'$ gauge interaction becomes strong at an intermediate scale and then we obtain a light composite Dirac fermion with U(1)$'$ gauge interaction at the low-energy scale. Its thermal relic can explain the observed amount of dark matter consistently with other cosmological and astrophysical constraints. We discuss that a nonzero kinetic mixing between the U(1)$'$ gauge boson and the Hypercharge gauge boson is allowed and the temperature of the visible sector and the dark matter sector can be equal to each other.
[ { "created": "Thu, 1 Aug 2019 04:54:50 GMT", "version": "v1" } ]
2020-07-22
[ [ "Kamada", "Ayuki", "" ], [ "Yamada", "Masaki", "" ], [ "Yanagida", "Tsutomu T.", "" ] ]
We provide a simple UV theory for a Dirac dark matter with a massless Abelian gauge boson. We introduce a single fermion transforming as the $\bf{16}$ representation in the SO(10)$'$ gauge group, which is assumed to be spontaneously broken to SU(5)$'\times$U(1)$'$. The SU(5)$'$ gauge interaction becomes strong at an intermediate scale and then we obtain a light composite Dirac fermion with U(1)$'$ gauge interaction at the low-energy scale. Its thermal relic can explain the observed amount of dark matter consistently with other cosmological and astrophysical constraints. We discuss that a nonzero kinetic mixing between the U(1)$'$ gauge boson and the Hypercharge gauge boson is allowed and the temperature of the visible sector and the dark matter sector can be equal to each other.
2009.12067
Kouji Kashiwa
Kouji Kashiwa, Hiroaki Kouno
Information theoretical view of QCD effective model with heavy quarks
8 pages, 3 figures
Phys. Rev. D 103, 014014 (2021)
10.1103/PhysRevD.103.014014
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
To understand the phase transition phenomena, information theoretical approaches can pick up some important properties of the phenomena based on the probability distribution. In this paper, we show information theoretical aspects of the 3-dimensional 3-state Potts model with the external field which is corresponding to the QCD effective model with heavy quarks. The transfer mutual information which represents the information flow of two spin variables is numerically estimated based on the Markov-chain Monte-Carlo method. The transfer mutual information has the peak near the confinement-deconfinement transition, and it may be used to detect the precursors of the transition. Since the transfer mutual information still have the peak even if the Polyakov-loop changes continuously and smoothly, we may pick up some aspects of the confinement-deconfinement nature from the information flow properties. Particularly, the transfer mutual information shows the significantly different behavior below and above the Roberge-Weiss endpoint existed in the pure imaginary chemical potential region, which may indicate the system change by the confinement-deconfinement transition.
[ { "created": "Fri, 25 Sep 2020 07:34:20 GMT", "version": "v1" } ]
2021-01-20
[ [ "Kashiwa", "Kouji", "" ], [ "Kouno", "Hiroaki", "" ] ]
To understand the phase transition phenomena, information theoretical approaches can pick up some important properties of the phenomena based on the probability distribution. In this paper, we show information theoretical aspects of the 3-dimensional 3-state Potts model with the external field which is corresponding to the QCD effective model with heavy quarks. The transfer mutual information which represents the information flow of two spin variables is numerically estimated based on the Markov-chain Monte-Carlo method. The transfer mutual information has the peak near the confinement-deconfinement transition, and it may be used to detect the precursors of the transition. Since the transfer mutual information still have the peak even if the Polyakov-loop changes continuously and smoothly, we may pick up some aspects of the confinement-deconfinement nature from the information flow properties. Particularly, the transfer mutual information shows the significantly different behavior below and above the Roberge-Weiss endpoint existed in the pure imaginary chemical potential region, which may indicate the system change by the confinement-deconfinement transition.
2107.14775
Berndt Muller
Berndt M\"uller
$\eta/s-\hat{q}/T^3$ Relation at Next-to-Leading Order in QCD
Slightly amended version submitted for journal publication
Phys. Rev. D 104, 071501 (2021)
10.1103/PhysRevD.104.L071501
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
The relation between the specific shear viscosity $\eta/s$ and the dimensionless jet quenching parameter $\hat{q}/T^3$ in perturbative QCD is explored at next-to-leading order in the coupling constant. It is shown that the relation changes little, although both transport coefficients independently are subject to large modifications at the NLO level. This finding confirms that the relationship is robust.
[ { "created": "Fri, 30 Jul 2021 17:27:47 GMT", "version": "v1" }, { "created": "Tue, 3 Aug 2021 17:57:59 GMT", "version": "v2" } ]
2021-10-13
[ [ "Müller", "Berndt", "" ] ]
The relation between the specific shear viscosity $\eta/s$ and the dimensionless jet quenching parameter $\hat{q}/T^3$ in perturbative QCD is explored at next-to-leading order in the coupling constant. It is shown that the relation changes little, although both transport coefficients independently are subject to large modifications at the NLO level. This finding confirms that the relationship is robust.
1801.02670
Antonio Morais
Thibault Vieu, Ant\'onio P. Morais and Roman Pasechnik
Electroweak phase transitions in multi-Higgs models: the case of Trinification-inspired THDSM
48 pages, 13 figures
null
10.1088/1475-7516/2018/07/014
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The rich vacuum structure of multi-Higgs extensions of the Standard Model (SM) may have interesting cosmological implications for the electroweak phase transition (EWPT). As an important example of such class of models, we consider a particularly simple low-energy SM-like limit of a recently proposed Grand-Unified Trinification model with the scalar sector composed of two Higgs doublets and a complex singlet and with a global $\mathrm{U}(1)$ family symmetry. The fermion sector of this model is extended with a family of vector-like quarks which enhances CP violation. With the current study, we aim at exploring the generic vacuum structure and uncovering the features of the EWPT in this model relevant for cosmology. We show the existence of different phase transition patterns providing strong departure from thermal equilibrium. Most of these observations are not specific to the considered model and may generically be expected in other multi-Higgs extensions of the SM.
[ { "created": "Mon, 8 Jan 2018 20:10:27 GMT", "version": "v1" } ]
2018-07-18
[ [ "Vieu", "Thibault", "" ], [ "Morais", "António P.", "" ], [ "Pasechnik", "Roman", "" ] ]
The rich vacuum structure of multi-Higgs extensions of the Standard Model (SM) may have interesting cosmological implications for the electroweak phase transition (EWPT). As an important example of such class of models, we consider a particularly simple low-energy SM-like limit of a recently proposed Grand-Unified Trinification model with the scalar sector composed of two Higgs doublets and a complex singlet and with a global $\mathrm{U}(1)$ family symmetry. The fermion sector of this model is extended with a family of vector-like quarks which enhances CP violation. With the current study, we aim at exploring the generic vacuum structure and uncovering the features of the EWPT in this model relevant for cosmology. We show the existence of different phase transition patterns providing strong departure from thermal equilibrium. Most of these observations are not specific to the considered model and may generically be expected in other multi-Higgs extensions of the SM.
hep-ph/0211235
Osamu Kiriyama
O. Kiriyama and A. Hosaka
Chiral phase properties of finite size quark droplets in the Nambu--Jona-Lasinio model
RevTex4, 9 pages, 6 figures, to be published in Phys. Rev. D
Phys.Rev. D67 (2003) 085010
10.1103/PhysRevD.67.085010
RCNP-Th02019
hep-ph astro-ph nucl-th
null
Chiral phase properties of finite size hadronic systems are investigated within the Nambu--Jona-Lasinio model. Finite size effects are taken into account by making use of the multiple reflection expansion. We find that, for droplets with relatively small baryon numbers, chiral symmetry restoration is enhanced by the finite size effects. However the radius of the stable droplet does not change much, as compared to that without the multiple reflection expansion.
[ { "created": "Fri, 15 Nov 2002 03:07:36 GMT", "version": "v1" }, { "created": "Sat, 16 Nov 2002 02:05:39 GMT", "version": "v2" }, { "created": "Tue, 3 Dec 2002 06:13:37 GMT", "version": "v3" }, { "created": "Wed, 19 Feb 2003 07:36:27 GMT", "version": "v4" } ]
2009-11-07
[ [ "Kiriyama", "O.", "" ], [ "Hosaka", "A.", "" ] ]
Chiral phase properties of finite size hadronic systems are investigated within the Nambu--Jona-Lasinio model. Finite size effects are taken into account by making use of the multiple reflection expansion. We find that, for droplets with relatively small baryon numbers, chiral symmetry restoration is enhanced by the finite size effects. However the radius of the stable droplet does not change much, as compared to that without the multiple reflection expansion.
hep-ph/9802206
Xiaotong Song
Xiaotong Song
Orbital Angular Momentum in the Chiral Quark Model
18 pages, 8 tables, revtex; typos corrected, numerical results slightly changed in Eq.(18)-(20) and in Table IV, reference added
null
null
INPP-UVA-97-08, December, 1997 (Revised April 20, 1998)
hep-ph
null
We developed a new and unified scheme for describing both quark spin and orbital angular momenta in symmetry-breaking chiral quark model. The loss of quark spin in the chiral splitting processes is compensated by the gain of the orbital angular momentum carried by quarks and antiquarks. The sum of both spin and orbital angular momenta carried by quarks and antiquarks is 1/2. The analytic and numerical results for the spin and orbital angular momenta carried by quarks and antiquarks in the nucleon are given. Extension to other octet and decuplet baryons is also presented. Possible modification and application are discussed.
[ { "created": "Sat, 31 Jan 1998 22:49:22 GMT", "version": "v1" }, { "created": "Mon, 20 Apr 1998 23:52:15 GMT", "version": "v2" }, { "created": "Wed, 6 May 1998 00:18:48 GMT", "version": "v3" } ]
2007-05-23
[ [ "Song", "Xiaotong", "" ] ]
We developed a new and unified scheme for describing both quark spin and orbital angular momenta in symmetry-breaking chiral quark model. The loss of quark spin in the chiral splitting processes is compensated by the gain of the orbital angular momentum carried by quarks and antiquarks. The sum of both spin and orbital angular momenta carried by quarks and antiquarks is 1/2. The analytic and numerical results for the spin and orbital angular momenta carried by quarks and antiquarks in the nucleon are given. Extension to other octet and decuplet baryons is also presented. Possible modification and application are discussed.
0806.2301
Andrea Ferroglia
R. Bonciani, A. Ferroglia, T. Gehrmann, D. Maitre, and C. Studerus
Two-Loop Fermionic Corrections to Heavy-Quark Pair Production: the Quark-Antiquark Channel
23 pages, 4 figures
JHEP 0807:129,2008
10.1088/1126-6708/2008/07/129
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We evaluate the fermionic two-loop QCD corrections to the heavy-quark pair production process in the quark-antiquark channel. We obtain analytic results which are valid for any value of the Mandelstam invariants s and t, and of the heavy quark mass m. Our findings confirm previous results for the analytic evaluation in the small-mass limit and numerical results for the exact amplitude. We furthermore provide the expansion of the two-loop amplitude at the production threshold s ~ 4m^2.
[ { "created": "Fri, 13 Jun 2008 17:29:46 GMT", "version": "v1" } ]
2009-11-13
[ [ "Bonciani", "R.", "" ], [ "Ferroglia", "A.", "" ], [ "Gehrmann", "T.", "" ], [ "Maitre", "D.", "" ], [ "Studerus", "C.", "" ] ]
We evaluate the fermionic two-loop QCD corrections to the heavy-quark pair production process in the quark-antiquark channel. We obtain analytic results which are valid for any value of the Mandelstam invariants s and t, and of the heavy quark mass m. Our findings confirm previous results for the analytic evaluation in the small-mass limit and numerical results for the exact amplitude. We furthermore provide the expansion of the two-loop amplitude at the production threshold s ~ 4m^2.
hep-ph/0406326
Patricia Ball
Patricia Ball
The Theory of CP-Violation -- in as Much of a Nutshell as Will Fit on 8 Pages
8 pages, review talk given at Daphne 2004, Frascati June 2004
null
null
null
hep-ph
null
Do you know that CP violation is intrinsically linked to the scalar sector of the Standard Model and its extensions? If yes, you need read no further - if no, you may turn over the titlepage and start reading now.
[ { "created": "Tue, 29 Jun 2004 16:10:47 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ball", "Patricia", "" ] ]
Do you know that CP violation is intrinsically linked to the scalar sector of the Standard Model and its extensions? If yes, you need read no further - if no, you may turn over the titlepage and start reading now.
2008.09276
Ya-Peng Zhao
Ya-Peng Zhao, Shu-Yu Zuo, and Cheng-Ming Li
QCD phase diagram and critical exponents within the nonextensive Polyakov-Nambu-Jona-Lasinio model
arXiv admin note: substantial text overlap with arXiv:2004.14556
null
10.1088/1674-1137/abf8a2
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a nonextensive version of the Polyakov-Nambu-Jona-Lasinio model which is based on the nonextentive statistical mechanics. This new statistics is characterized by a dimensionless nonextensivity parameter $q$ that accounts for all possible effects violating the assumptions of the Boltzmann-Gibbs (BG) statistics (when $q\rightarrow1$, it returns to the BG case). Based on the nonextensive Polyakov-Nambu-Jona-Lasinio model, we discussed the influence of the nonextensive effects on the QCD phase transition, especially on the location of the critical end point (CEP). A new and interesting phenomenon we found is that with the increase of $q$, the CEP position initially shifted toward the direction of larger chemical potential and lower temperature. But then, when $q$ is greater than a critical value $q_{c}$, the CEP position moves in the opposite direction. In other words, as $q$ increases, the CEP position moves in the direction of smaller chemical potential and higher temperature. In addition, we calculated the influence of the nonextensive effects on the critical exponents and found that they remain almost constant with $q$.
[ { "created": "Fri, 21 Aug 2020 02:49:28 GMT", "version": "v1" } ]
2021-09-01
[ [ "Zhao", "Ya-Peng", "" ], [ "Zuo", "Shu-Yu", "" ], [ "Li", "Cheng-Ming", "" ] ]
We present a nonextensive version of the Polyakov-Nambu-Jona-Lasinio model which is based on the nonextentive statistical mechanics. This new statistics is characterized by a dimensionless nonextensivity parameter $q$ that accounts for all possible effects violating the assumptions of the Boltzmann-Gibbs (BG) statistics (when $q\rightarrow1$, it returns to the BG case). Based on the nonextensive Polyakov-Nambu-Jona-Lasinio model, we discussed the influence of the nonextensive effects on the QCD phase transition, especially on the location of the critical end point (CEP). A new and interesting phenomenon we found is that with the increase of $q$, the CEP position initially shifted toward the direction of larger chemical potential and lower temperature. But then, when $q$ is greater than a critical value $q_{c}$, the CEP position moves in the opposite direction. In other words, as $q$ increases, the CEP position moves in the direction of smaller chemical potential and higher temperature. In addition, we calculated the influence of the nonextensive effects on the critical exponents and found that they remain almost constant with $q$.
hep-ph/9607310
null
Marion Flanz, Emmanuel A. Paschos, Utpal Sarkar and Jan Weiss
Baryogenesis Through Mixing of Heavy Majorana Neutrinos
15 pages (including 4 eps files)
Phys.Lett. B389 (1996) 693-699
10.1016/S0370-2693(96)01337-8
null
hep-ph
null
A mechanism is presented, in which the mixing of right handed heavy Majorana neutrinos creates a $CP-$asymmetric universe. When these Majorana neutrinos subsequently decay more leptons than anti-leptons are produced. The lepton asymmetry created by this new mechanism can exceed by a few orders of magnitude any lepton asymmetry originating from direct decays. The asymmetry is finally converted into a baryon asymmetry during the electroweak phase transition.
[ { "created": "Mon, 15 Jul 1996 10:35:39 GMT", "version": "v1" } ]
2009-10-28
[ [ "Flanz", "Marion", "" ], [ "Paschos", "Emmanuel A.", "" ], [ "Sarkar", "Utpal", "" ], [ "Weiss", "Jan", "" ] ]
A mechanism is presented, in which the mixing of right handed heavy Majorana neutrinos creates a $CP-$asymmetric universe. When these Majorana neutrinos subsequently decay more leptons than anti-leptons are produced. The lepton asymmetry created by this new mechanism can exceed by a few orders of magnitude any lepton asymmetry originating from direct decays. The asymmetry is finally converted into a baryon asymmetry during the electroweak phase transition.
1403.5717
Yu Gao
Rouzbeh Allahverdi, Bhaskar Dutta, Yu Gao
keV Photon Emission from Light Nonthermal Dark Matter
3 pages, 1 figure
Phys. Rev. D 89, 127305 (2014)
10.1103/PhysRevD.89.127305
MIFPA-14-10
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a possible explanation for the recent claim of an excess at 3.5 keV in the X-ray spectrum within a minimal extension of the standard model that explains dark matter and baryon abundance of the universe. The dark matter mass in this model is ${\cal O}({\rm GeV})$ and its relic density has a non-thermal origin. The model includes two colored scalars of ${\cal O}({\rm TeV})$ mass ($X_{1,2}$), and two singlet fermions that are almost degenerate in mass with the proton ($N_{1,2}$). The heavier fermion $N_2$ undergoes radiative decay to the lighter one $N_1$ that is absolutely stable. Radiative decay with a life time $\sim 10^{23}$ seconds can account for the claimed 3.5 keV line, which requires couplings $\sim 10^{-3}-10^{-1}$ between $X_{1,2}, ~ N_{1,2}$ and the up-type quarks. The model also gives rise to potentially detectable monojet, dijet, and monotop signals at the LHC.
[ { "created": "Sun, 23 Mar 2014 03:31:18 GMT", "version": "v1" } ]
2014-07-09
[ [ "Allahverdi", "Rouzbeh", "" ], [ "Dutta", "Bhaskar", "" ], [ "Gao", "Yu", "" ] ]
We propose a possible explanation for the recent claim of an excess at 3.5 keV in the X-ray spectrum within a minimal extension of the standard model that explains dark matter and baryon abundance of the universe. The dark matter mass in this model is ${\cal O}({\rm GeV})$ and its relic density has a non-thermal origin. The model includes two colored scalars of ${\cal O}({\rm TeV})$ mass ($X_{1,2}$), and two singlet fermions that are almost degenerate in mass with the proton ($N_{1,2}$). The heavier fermion $N_2$ undergoes radiative decay to the lighter one $N_1$ that is absolutely stable. Radiative decay with a life time $\sim 10^{23}$ seconds can account for the claimed 3.5 keV line, which requires couplings $\sim 10^{-3}-10^{-1}$ between $X_{1,2}, ~ N_{1,2}$ and the up-type quarks. The model also gives rise to potentially detectable monojet, dijet, and monotop signals at the LHC.
1310.1627
Vladimir Kovalenko
Evgeniia Bodnia (1 and 2), Denis Derkach (3), Grigory Feofilov (2), Vladimir Kovalenko (2), Andrey Puchkov (2) ((1) University of California, Berkeley, USA, (2) Saint Petersburg State University, Russia, (3) Oxford University, UK)
Multi-pomeron exchange model for $pp$ and $p\bar{p}$ collisions at ultra-high energy
7 pages, 7 figures, to appear in proc. QFTHEP'2013
null
10.22323/1.183.0060
null
hep-ph nucl-th
http://creativecommons.org/licenses/by-nc-sa/3.0/
A new variant of the effective pomeron exchange model is proposed for the description of the correlation, observed in $pp$ and $p\bar{p}$ collisions at center-of-mass energy from SPS to LHC, between mean transverse momentum and charged particles multiplicity. The model is based on the Regge-Gribov approach. Smooth logarithmic growth with the collision energy was established for the parameter k, the mean rapidity density of charged particles produced by a single string. It was obtained in the model by the fitting of the available experimental data on charged particles rapidity density in $pp$ and $p\bar{p}$ collisions. The main effect of the model, a gradual onset of string collectivity with the growth of collision energy, is accounted by a free parameter {\beta} that is responsible in an effective way for the string fusion phenomenon. Another free parameter, t, is used to define string tension. We extract parameters {\beta} and t from the available experimental results on <pt>-multiplicity correlation at nucleon collision energy $\sqrt{s}$ from 17 GeV to 7 TeV. Smooth dependence of both {\beta} and t on energy allows to make predictions for the correlation behavior at the collision energy of 14 TeV. The indications to the string interaction effects in high multiplicity events in $pp$ collisions at the LHC energies are also discussed.
[ { "created": "Sun, 6 Oct 2013 20:45:53 GMT", "version": "v1" } ]
2022-09-21
[ [ "Bodnia", "Evgeniia", "", "1 and 2" ], [ "Derkach", "Denis", "" ], [ "Feofilov", "Grigory", "" ], [ "Kovalenko", "Vladimir", "" ], [ "Puchkov", "Andrey", "" ] ]
A new variant of the effective pomeron exchange model is proposed for the description of the correlation, observed in $pp$ and $p\bar{p}$ collisions at center-of-mass energy from SPS to LHC, between mean transverse momentum and charged particles multiplicity. The model is based on the Regge-Gribov approach. Smooth logarithmic growth with the collision energy was established for the parameter k, the mean rapidity density of charged particles produced by a single string. It was obtained in the model by the fitting of the available experimental data on charged particles rapidity density in $pp$ and $p\bar{p}$ collisions. The main effect of the model, a gradual onset of string collectivity with the growth of collision energy, is accounted by a free parameter {\beta} that is responsible in an effective way for the string fusion phenomenon. Another free parameter, t, is used to define string tension. We extract parameters {\beta} and t from the available experimental results on <pt>-multiplicity correlation at nucleon collision energy $\sqrt{s}$ from 17 GeV to 7 TeV. Smooth dependence of both {\beta} and t on energy allows to make predictions for the correlation behavior at the collision energy of 14 TeV. The indications to the string interaction effects in high multiplicity events in $pp$ collisions at the LHC energies are also discussed.
1111.1849
Yuming Wang
Thomas Mannel and Yu-Ming Wang
Heavy-to-light baryonic form factors at large recoil
19 pages
null
10.1007/JHEP12(2011)067
SI-HEP-2011-12
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze heavy-to-light baryonic form factors at large recoil and derive the scaling behavior of these form factors in the heavy quark limit. It is shown that only one universal form factor is needed to parameterize Lambda_b to p and Lambda_b to Lambda matrix elements in the large recoil limit of light baryons, while hadronic matrix elements of Lambda_b to Sigma transition vanish in the large energy limit of Sigma baryon due to the space-time parity symmetry. The scaling law of the soft form factor eta(P^{\prime} \cdot v), P^{\prime} and v being the momentum of nucleon and the velocity of Lambda_b baryon, responsible for Lambda_b to p transitions is also derived using the nucleon distribution amplitudes in leading conformal spin. In particular, we verify that this scaling behavior is in full agreement with that from light-cone sum rule approach in the heavy-quark limit. With these form factors, we further investigate the Lambda baryon polarization asymmetry alpha in Lambda_b to Lambda gamma and the forward-backward asymmetry A_{FB} in Lambda_b to Lambda l^{+} l^{-}. Both two observables (alpha and A_{FB}) are independent of hadronic form factors in leading power of 1/m_b and in leading order of alpha_s. We also extend the analysis of hadronic matrix elements for Omega_b to Omega transitions to rare Omega_b to Omega gamma and Omega_b to Omega l^{+} l^{-} decays and find that radiative Omega_b to Omega gamma decay is probably the most promising FCNC b to s radiative baryonic decay channel. In addition, it is interesting to notice that the zero-point of forward-backward asymmetry of Omega_b to Omega l^{+} l^{-} is the same as the one for Lambda_b to Lambda l^{+} l^{-} to leading order accuracy provided that the form factors \bar{\zeta}_i (i=3, 4, 5) are numerically as small as indicated from the quark model.
[ { "created": "Tue, 8 Nov 2011 10:05:00 GMT", "version": "v1" } ]
2015-06-03
[ [ "Mannel", "Thomas", "" ], [ "Wang", "Yu-Ming", "" ] ]
We analyze heavy-to-light baryonic form factors at large recoil and derive the scaling behavior of these form factors in the heavy quark limit. It is shown that only one universal form factor is needed to parameterize Lambda_b to p and Lambda_b to Lambda matrix elements in the large recoil limit of light baryons, while hadronic matrix elements of Lambda_b to Sigma transition vanish in the large energy limit of Sigma baryon due to the space-time parity symmetry. The scaling law of the soft form factor eta(P^{\prime} \cdot v), P^{\prime} and v being the momentum of nucleon and the velocity of Lambda_b baryon, responsible for Lambda_b to p transitions is also derived using the nucleon distribution amplitudes in leading conformal spin. In particular, we verify that this scaling behavior is in full agreement with that from light-cone sum rule approach in the heavy-quark limit. With these form factors, we further investigate the Lambda baryon polarization asymmetry alpha in Lambda_b to Lambda gamma and the forward-backward asymmetry A_{FB} in Lambda_b to Lambda l^{+} l^{-}. Both two observables (alpha and A_{FB}) are independent of hadronic form factors in leading power of 1/m_b and in leading order of alpha_s. We also extend the analysis of hadronic matrix elements for Omega_b to Omega transitions to rare Omega_b to Omega gamma and Omega_b to Omega l^{+} l^{-} decays and find that radiative Omega_b to Omega gamma decay is probably the most promising FCNC b to s radiative baryonic decay channel. In addition, it is interesting to notice that the zero-point of forward-backward asymmetry of Omega_b to Omega l^{+} l^{-} is the same as the one for Lambda_b to Lambda l^{+} l^{-} to leading order accuracy provided that the form factors \bar{\zeta}_i (i=3, 4, 5) are numerically as small as indicated from the quark model.
1301.3478
Denis Parganlija
Denis Parganlija (Vienna, Tech. U.), Peter Kovacs (Budapest, RMKI), Gyorgy Wolf (Budapest, RMKI), Francesco Giacosa (Frankfurt U.) and Dirk H. Rischke (Frankfurt U. and Frankfurt U., FIAS)
Eta, Eta' and eLSM
Prepared for Proceedings of Xth Conference on Quark Confinement and the Hadron Spectrum, October 8-12, 2012, TUM Campus Garching, Munich, Germany. 8 pages. v2 contains updated reference list
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the eta-eta' mixing in the Extended Linear Sigma Model (eLSM).
[ { "created": "Tue, 15 Jan 2013 20:33:03 GMT", "version": "v1" }, { "created": "Tue, 26 Mar 2013 18:09:21 GMT", "version": "v2" } ]
2013-03-27
[ [ "Parganlija", "Denis", "", "Vienna, Tech. U." ], [ "Kovacs", "Peter", "", "Budapest, RMKI" ], [ "Wolf", "Gyorgy", "", "Budapest, RMKI" ], [ "Giacosa", "Francesco", "", "Frankfurt U." ], [ "Rischke", "Dirk H.", "", "Frankfurt U. and Frankfurt U., FIAS" ] ]
We discuss the eta-eta' mixing in the Extended Linear Sigma Model (eLSM).
hep-ph/0604123
Ana Julia Mizher
Ana J\'ulia Mizher, Eduardo S. Fraga and Gast\~ao Krein
Langevin dynamics of the deconfinement transition for pure gauge theory
4 pages, 3 figures. To appear in the proceedings of I Latin American Workshop on High Energy Phenomenology (LAWHEP 2005), Porto Alegre, Brazil, 1-3 Dec 2005. v2: minor corrections
Braz.J.Phys.37:605-608,2007
10.1590/S0103-97332007000400022
null
hep-ph hep-lat hep-th
null
We investigate the effects of dissipation in the deconfinement transition for pure SU(2) and SU(3) gauge theories. Using an effective theory for the order parameter, we study its Langevin evolution numerically. Noise effects are included for the case of SU(2). We find that both dissipation and noise have dramatic effects on the spinodal decomposition of the order parameter and delay considerably its thermalization. For SU(3) the effects of dissipation are even larger than for SU(2).
[ { "created": "Thu, 13 Apr 2006 16:30:22 GMT", "version": "v1" }, { "created": "Mon, 17 Apr 2006 18:26:13 GMT", "version": "v2" } ]
2011-08-04
[ [ "Mizher", "Ana Júlia", "" ], [ "Fraga", "Eduardo S.", "" ], [ "Krein", "Gastão", "" ] ]
We investigate the effects of dissipation in the deconfinement transition for pure SU(2) and SU(3) gauge theories. Using an effective theory for the order parameter, we study its Langevin evolution numerically. Noise effects are included for the case of SU(2). We find that both dissipation and noise have dramatic effects on the spinodal decomposition of the order parameter and delay considerably its thermalization. For SU(3) the effects of dissipation are even larger than for SU(2).
1410.3165
Hua Xing Zhu
Jun Gao and Hua Xing Zhu
Top-quark forward-backward asymmetry in e+e- annihilation at NNLO in QCD
6 pages, 5 figures. arXiv admin note: text overlap with arXiv:1408.5150
Phys. Rev. Lett. 113, 262001 (2014)
10.1103/PhysRevLett.113.262001
SLAC-PUB-16101, SMU-HEP-14-08
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report on a complete calculation of electroweak production of top quark pairs in $e^+e^-$ annihilation at next-to-next-to-leading order in Quantum Chromodynamics. Our setup is fully differential and can be used to calculate any infrared-safe observable. Especially we calculated the next-to-next-to-leading order corrections to top-quark forward-backward asymmetry and found sizable effects. Our results show a large reduction of the theoretical uncertainties in predictions of the forward-backward asymmetry, and allow a precision determination of the top quark electroweak couplings at future $e^+e^-$ colliders.
[ { "created": "Sun, 12 Oct 2014 23:25:39 GMT", "version": "v1" } ]
2015-01-07
[ [ "Gao", "Jun", "" ], [ "Zhu", "Hua Xing", "" ] ]
We report on a complete calculation of electroweak production of top quark pairs in $e^+e^-$ annihilation at next-to-next-to-leading order in Quantum Chromodynamics. Our setup is fully differential and can be used to calculate any infrared-safe observable. Especially we calculated the next-to-next-to-leading order corrections to top-quark forward-backward asymmetry and found sizable effects. Our results show a large reduction of the theoretical uncertainties in predictions of the forward-backward asymmetry, and allow a precision determination of the top quark electroweak couplings at future $e^+e^-$ colliders.
1102.4214
Mauro Anselmino
Mauro Anselmino, Vincenzo Barone and Aram Kotzinian
SIDIS in the target fragmentation region: polarized and transverse momentum dependent fracture functions
18 pages, 2 figures. Some equations modified and text shortened; main conclusions unchanged
Phys.Lett.B699:108-118,2011
10.1016/j.physletb.2011.03.067
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The target fragmentation region of semi-inclusive deep inelastic scattering is described at leading twist, taking beam and target polarizations into account. The formalism of polarized and transverse-momentum dependent fracture functions is developed and the observables for some specific processes are presented.
[ { "created": "Mon, 21 Feb 2011 13:13:15 GMT", "version": "v1" }, { "created": "Fri, 25 Feb 2011 15:47:07 GMT", "version": "v2" } ]
2011-04-20
[ [ "Anselmino", "Mauro", "" ], [ "Barone", "Vincenzo", "" ], [ "Kotzinian", "Aram", "" ] ]
The target fragmentation region of semi-inclusive deep inelastic scattering is described at leading twist, taking beam and target polarizations into account. The formalism of polarized and transverse-momentum dependent fracture functions is developed and the observables for some specific processes are presented.
hep-ph/9805213
Yang Chun-Bin
C.B. Yang and X. Cai (Hua-Zhong Normal Univ. China)
Scaling Behavior of Multiplicity Distribution under First-Order Quark-Hadron Phase Transition
5 pages in Revtex, 5 eps figures
J.Phys.G25:485-492,1999
10.1088/0954-3899/25/3/001
null
hep-ph
null
Multiplicity distribution in small bins is studied within the Ginzburg-Landau description for first-order quark-hadron phase transition. Direct comparison of the distribution with a Poisson one (with the same average) is made. Dynamical factor $d_q$ for the distributionand ratio $D_q\equiv d_q/d_1$ are studied, and novel scaling behaviors between $D_q$ are found which can be used to detect the formation of quark-gluon plasma.
[ { "created": "Mon, 4 May 1998 06:34:47 GMT", "version": "v1" } ]
2008-11-26
[ [ "Yang", "C. B.", "", "Hua-Zhong Normal Univ. China" ], [ "Cai", "X.", "", "Hua-Zhong Normal Univ. China" ] ]
Multiplicity distribution in small bins is studied within the Ginzburg-Landau description for first-order quark-hadron phase transition. Direct comparison of the distribution with a Poisson one (with the same average) is made. Dynamical factor $d_q$ for the distributionand ratio $D_q\equiv d_q/d_1$ are studied, and novel scaling behaviors between $D_q$ are found which can be used to detect the formation of quark-gluon plasma.
1712.06450
Felix Karbstein
Holger Gies, Felix Karbstein, Christian Kohlf\"urst, Nico Seegert
Photon-photon scattering at the high-intensity frontier
7 pages, 2 figures; matches journal version
Phys. Rev. D 97, 076002 (2018)
10.1103/PhysRevD.97.076002
null
hep-ph hep-th physics.optics physics.plasm-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The tremendous progress in high-intensity laser technology and the establishment of dedicated high-field laboratories in recent years have paved the way towards a first observation of quantum vacuum nonlinearities at the high-intensity frontier. We advocate a particularly prospective scenario, where three synchronized high-intensity laser pulses are brought into collision, giving rise to signal photons, whose frequency and propagation direction differ from the driving laser pulses, thus providing various means to achieve an excellent signal to background separation. Based on the theoretical concept of vacuum emission, we employ an efficient numerical algorithm which allows us to model the collision of focused high-intensity laser pulses in unprecedented detail. We provide accurate predictions for the numbers of signal photons accessible in experiment. Our study paves the way for a first verification of quantum vacuum nonlinearity in a well-controlled laboratory experiment at one of the many high-intensity laser facilities currently coming online.
[ { "created": "Fri, 15 Dec 2017 14:22:44 GMT", "version": "v1" }, { "created": "Tue, 10 Apr 2018 09:30:41 GMT", "version": "v2" } ]
2018-04-11
[ [ "Gies", "Holger", "" ], [ "Karbstein", "Felix", "" ], [ "Kohlfürst", "Christian", "" ], [ "Seegert", "Nico", "" ] ]
The tremendous progress in high-intensity laser technology and the establishment of dedicated high-field laboratories in recent years have paved the way towards a first observation of quantum vacuum nonlinearities at the high-intensity frontier. We advocate a particularly prospective scenario, where three synchronized high-intensity laser pulses are brought into collision, giving rise to signal photons, whose frequency and propagation direction differ from the driving laser pulses, thus providing various means to achieve an excellent signal to background separation. Based on the theoretical concept of vacuum emission, we employ an efficient numerical algorithm which allows us to model the collision of focused high-intensity laser pulses in unprecedented detail. We provide accurate predictions for the numbers of signal photons accessible in experiment. Our study paves the way for a first verification of quantum vacuum nonlinearity in a well-controlled laboratory experiment at one of the many high-intensity laser facilities currently coming online.
0809.2669
Manuel B\"ahr
Manuel B\"ahr, Stefan Gieseke and Michael H. Seymour
Underlying events in Herwig++
4 pages, 3 figures, to appear in the proceedings of the "HERA and the LHC" workshop
null
null
CERN-PH-TH-2008-195, KA-TP-22-2008, MCnet/08/11
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this contribution we describe the new model of multiple partonic interactions (MPI) that has been implemented in Herwig++. Tuning its two free parameters is enough to find a good description of CDF underlying event data. We show extrapolations to the LHC and compare them to results from other models.
[ { "created": "Tue, 16 Sep 2008 13:36:12 GMT", "version": "v1" } ]
2008-09-17
[ [ "Bähr", "Manuel", "" ], [ "Gieseke", "Stefan", "" ], [ "Seymour", "Michael H.", "" ] ]
In this contribution we describe the new model of multiple partonic interactions (MPI) that has been implemented in Herwig++. Tuning its two free parameters is enough to find a good description of CDF underlying event data. We show extrapolations to the LHC and compare them to results from other models.
hep-ph/9805234
Francesco Murgia
M. Anselmino (1), M. Bertini (1 and 2), F. Murgia (3) and B. Pire (4) ((1) University and INFN, Torino, Italy, (2) IPN, Lyon, France, (3) University and INFN, Cagliari, Italy, (4) CPhT, Ecole Polytechnique, France)
Off-diagonal helicity density matrix elements for heavy vector mesons inclusively produced in N-N, gamma-N, l-N interactions
LaTeX, 10 pages, 1 postscript figure, uses epsfig.sty. Revised version, to be published on Phys. Lett. B. Some statements added to clarify text
Phys.Lett. B438 (1998) 347-352
10.1016/S0370-2693(98)00978-2
DFTT 16/98, CPhT-S610-0498, INFNCA-TH9804
hep-ph
null
Final state interactions in quark fragmentation may give origin to non zero values of the off-diagonal element rho_(1,-1) of the helicity density matrix of vector mesons V produced in current jets, with a large energy fraction x_E; the value of rho_(1,-1)(V) is related to the hard constituent dynamics and tests unusual properties of it. Some recent data on phi, K^* and D^* produced in e^+ e^- annihilations at LEP show such effects. Predictions are given here for rho_(1,-1) of heavy mesons produced in nucleon-nucleon, gamma-nucleon and lepton-nucleon interactions.
[ { "created": "Wed, 6 May 1998 12:33:24 GMT", "version": "v1" }, { "created": "Mon, 3 Aug 1998 13:33:01 GMT", "version": "v2" } ]
2009-10-31
[ [ "Anselmino", "M.", "", "1 and 2" ], [ "Bertini", "M.", "", "1 and 2" ], [ "Murgia", "F.", "" ], [ "Pire", "B.", "" ] ]
Final state interactions in quark fragmentation may give origin to non zero values of the off-diagonal element rho_(1,-1) of the helicity density matrix of vector mesons V produced in current jets, with a large energy fraction x_E; the value of rho_(1,-1)(V) is related to the hard constituent dynamics and tests unusual properties of it. Some recent data on phi, K^* and D^* produced in e^+ e^- annihilations at LEP show such effects. Predictions are given here for rho_(1,-1) of heavy mesons produced in nucleon-nucleon, gamma-nucleon and lepton-nucleon interactions.
1809.09500
Francesco Murgia
M. Anselmino, M. Boglione, U. D'Alesio, F. Murgia, A. Prokudin
Role of transverse momentum dependence of unpolarised parton distribution and fragmentation functions in the analysis of azimuthal spin asymmetries
21 pages, 9 figures (18 eps plots)
Phys. Rev. D 98, 094023 (2018)
10.1103/PhysRevD.98.094023
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Information on the Sivers distribution and the Collins fragmentation functions and their transverse momentum dependence is mainly based on fitting single spin asymmetry data from semi-inclusive deep inelastic scattering (SIDIS). Independent information, respectively on the Sivers distribution and the Collins fragmentation, can be obtained from Drell-Yan and $e^+e^-$ annihilation processes. In the SIDIS case, the transverse momentum of the final observed hadron, which is the quantity measured, is generated both by the average transverse momentum in the distribution and in the fragmentation functions. As a consequence, these are strongly correlated and a separate extraction is made difficult. In this paper we investigate, in a simple kinematical Gaussian configuration, this correlation, its role on the transverse single spin asymmetries in SIDIS and the consequences for predictions of the Sivers asymmetry in Drell-Yan processes and for the Collins asymmetry in $e^+e^-$ annihilation. We find that, in some cases, these effects can be relevant and must be carefully taken into account.
[ { "created": "Tue, 25 Sep 2018 14:03:02 GMT", "version": "v1" } ]
2018-12-05
[ [ "Anselmino", "M.", "" ], [ "Boglione", "M.", "" ], [ "D'Alesio", "U.", "" ], [ "Murgia", "F.", "" ], [ "Prokudin", "A.", "" ] ]
Information on the Sivers distribution and the Collins fragmentation functions and their transverse momentum dependence is mainly based on fitting single spin asymmetry data from semi-inclusive deep inelastic scattering (SIDIS). Independent information, respectively on the Sivers distribution and the Collins fragmentation, can be obtained from Drell-Yan and $e^+e^-$ annihilation processes. In the SIDIS case, the transverse momentum of the final observed hadron, which is the quantity measured, is generated both by the average transverse momentum in the distribution and in the fragmentation functions. As a consequence, these are strongly correlated and a separate extraction is made difficult. In this paper we investigate, in a simple kinematical Gaussian configuration, this correlation, its role on the transverse single spin asymmetries in SIDIS and the consequences for predictions of the Sivers asymmetry in Drell-Yan processes and for the Collins asymmetry in $e^+e^-$ annihilation. We find that, in some cases, these effects can be relevant and must be carefully taken into account.
2012.03839
Joydeep Chakrabortty
Supratim Das Bakshi, Joydeep Chakrabortty, Michael Spannowsky
Classifying Standard Model Extensions Effectively with Precision Observables
19 pages, 9 figures
Phys. Rev. D 103, 056019 (2021)
10.1103/PhysRevD.103.056019
IPPP/20/63
hep-ph hep-ex hep-th
http://creativecommons.org/licenses/by-nc-sa/4.0/
Effective theories are well established theoretical frameworks to describe the effect of energetically widely separated UV models on observables at lower energy scales. Due to the complexity of the effective theory when taking all the Standard Model symmetries and degrees of freedoms into account, tensioning the entire system in a completely agnostic way against experimental measurements results in constraints on the Wilson Coefficients of the effective operators that either bears little information or challenge intrinsic assumptions imposed on the effective field theory framework. In general, a specific high-scale extension of the Standard Model only induces a subset of all possible operators. Thus, by investigating which operators are induced by different classes of the Standard Model extensions and comparing to which precision observables they contribute, we show that it is possible to obtain an improved understanding of which UV model is realised in nature. We consider 15 UV models which are single scalar field extensions of the Standard Model and compute their dimension-6 operators after integrating out the heavy scalars up to 1-loop level. Only very few of these scenarios remain indistinguishable, while most of the models can be phenomenologically separated from one another. Most of these scenarios possess their own characteristic operator signature. Following the approach outlined here, a comparative analysis of a wide range of models will allow to assess at what level the effective field theory series can be truncated and which experimental measurements to prioritise.
[ { "created": "Mon, 7 Dec 2020 16:39:46 GMT", "version": "v1" } ]
2021-03-31
[ [ "Bakshi", "Supratim Das", "" ], [ "Chakrabortty", "Joydeep", "" ], [ "Spannowsky", "Michael", "" ] ]
Effective theories are well established theoretical frameworks to describe the effect of energetically widely separated UV models on observables at lower energy scales. Due to the complexity of the effective theory when taking all the Standard Model symmetries and degrees of freedoms into account, tensioning the entire system in a completely agnostic way against experimental measurements results in constraints on the Wilson Coefficients of the effective operators that either bears little information or challenge intrinsic assumptions imposed on the effective field theory framework. In general, a specific high-scale extension of the Standard Model only induces a subset of all possible operators. Thus, by investigating which operators are induced by different classes of the Standard Model extensions and comparing to which precision observables they contribute, we show that it is possible to obtain an improved understanding of which UV model is realised in nature. We consider 15 UV models which are single scalar field extensions of the Standard Model and compute their dimension-6 operators after integrating out the heavy scalars up to 1-loop level. Only very few of these scenarios remain indistinguishable, while most of the models can be phenomenologically separated from one another. Most of these scenarios possess their own characteristic operator signature. Following the approach outlined here, a comparative analysis of a wide range of models will allow to assess at what level the effective field theory series can be truncated and which experimental measurements to prioritise.
1411.1654
George Rupp
Marco Cardoso, George Rupp, and Eef van Beveren
Unquenched quark-model calculation of X(3872) electromagnetic decays
10 pages, 2 figures (3 plots), 10 tables, SVJOUR style; v2: typos corrected, 2 references added, remarks added on dipole approximation, version accepted for publication in Eur. Phys. J. C
Eur. Phys. J. C 75 (2015) 26
10.1140/epjc/s10052-014-3254-z
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A recent quark-model description of X(3872) as an unquenched $2\,{}^{3\!}P_1$ $c\bar{c}$ state is generalised by now including all relevant meson-meson configurations, in order to calculate the widths of the experimentally observed electromagnetic decays $X(3872) \to \gamma J/\psi$ and $X(3872) \to \gamma\psi(2S)$. Interestingly, the inclusion of additional two-meson channels, most importantly $D^\pm D^{\star\mp}$, leads to a sizeable increase of the $c\bar{c}$ probability in the total wave function, although the $D^0\bar{D}^{\star0}$ component remains the dominant one. As for the electromagnetic decays, unquenching strongly reduces the $\gamma\psi(2S)$ decay rate yet even more sharply enhances the $\gamma J/\psi$ rate, resulting in a decay ratio compatible with one experimental observation but in slight disagreement with two others. Nevertheless, the results show a dramatic improvement as compared to a quenched calculation with the same confinement force and parameters. Concretely, we obtain $\Gamma ( X(3872) \to \gamma \psi(2S) )=28.9$ keV and $\Gamma ( X(3872) \to \gamma J/\psi)=24.7$ keV, with branching ratio $\mathcal{R}_{\gamma\psi}=1.17$.
[ { "created": "Thu, 6 Nov 2014 16:22:14 GMT", "version": "v1" }, { "created": "Tue, 23 Dec 2014 13:20:01 GMT", "version": "v2" } ]
2015-01-28
[ [ "Cardoso", "Marco", "" ], [ "Rupp", "George", "" ], [ "van Beveren", "Eef", "" ] ]
A recent quark-model description of X(3872) as an unquenched $2\,{}^{3\!}P_1$ $c\bar{c}$ state is generalised by now including all relevant meson-meson configurations, in order to calculate the widths of the experimentally observed electromagnetic decays $X(3872) \to \gamma J/\psi$ and $X(3872) \to \gamma\psi(2S)$. Interestingly, the inclusion of additional two-meson channels, most importantly $D^\pm D^{\star\mp}$, leads to a sizeable increase of the $c\bar{c}$ probability in the total wave function, although the $D^0\bar{D}^{\star0}$ component remains the dominant one. As for the electromagnetic decays, unquenching strongly reduces the $\gamma\psi(2S)$ decay rate yet even more sharply enhances the $\gamma J/\psi$ rate, resulting in a decay ratio compatible with one experimental observation but in slight disagreement with two others. Nevertheless, the results show a dramatic improvement as compared to a quenched calculation with the same confinement force and parameters. Concretely, we obtain $\Gamma ( X(3872) \to \gamma \psi(2S) )=28.9$ keV and $\Gamma ( X(3872) \to \gamma J/\psi)=24.7$ keV, with branching ratio $\mathcal{R}_{\gamma\psi}=1.17$.
1910.08561
Ethan Neil
Thomas DeGrand and Ethan T. Neil
Repurposing lattice QCD results for composite phenomenology
36 pages, 14 figures. v2: updated to journal version, including new appendix on pion decay constant conventions
Phys. Rev. D 101, 034504 (2020)
10.1103/PhysRevD.101.034504
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A number of proposed extensions of the Standard Model include new strongly interacting dynamics, in the form of SU(N) gauge fields coupled to various numbers of fermions. Often, these extensions allow N = 3 as a plausible choice, or even require N = 3, such as in twin Higgs models, where the new dynamics is a "copy" of QCD. However, the fermion masses in such a sector are typically different from (often heavier than) the ones of real-world QCD, relative to the confinement scale. Many of the strong interaction masses and matrix elements for SU(3) at heavy fermion masses have already been computed on the lattice, typically as a byproduct of the approach to the physical point of real QCD. We provide a summary of these relevant results for the phenomenological community.
[ { "created": "Fri, 18 Oct 2019 18:00:02 GMT", "version": "v1" }, { "created": "Mon, 24 Feb 2020 18:30:47 GMT", "version": "v2" } ]
2020-02-25
[ [ "DeGrand", "Thomas", "" ], [ "Neil", "Ethan T.", "" ] ]
A number of proposed extensions of the Standard Model include new strongly interacting dynamics, in the form of SU(N) gauge fields coupled to various numbers of fermions. Often, these extensions allow N = 3 as a plausible choice, or even require N = 3, such as in twin Higgs models, where the new dynamics is a "copy" of QCD. However, the fermion masses in such a sector are typically different from (often heavier than) the ones of real-world QCD, relative to the confinement scale. Many of the strong interaction masses and matrix elements for SU(3) at heavy fermion masses have already been computed on the lattice, typically as a byproduct of the approach to the physical point of real QCD. We provide a summary of these relevant results for the phenomenological community.
hep-ph/9802358
Christopher Kolda
Christopher Kolda and John March-Russell (IAS, Princeton)
Supersymmetric D-term Inflation, Reheating and Affleck-Dine Baryogenesis
23 pages LaTeX
Phys.Rev. D60 (1999) 023504
10.1103/PhysRevD.60.023504
IASSNS-HEP-98/007
hep-ph astro-ph
null
The phenomenology of supersymmetric models of inflation, where the inflationary vacuum energy is dominated by D-terms of a U(1), is investigated. Particular attention is paid to the questions of how to arrange for sufficient e-folds of inflation to occur, what kind of thermal history is expected after the end of inflation, and how to implement successful baryogenesis. Such models are argued to require a more restrictive symmetry structure than previously thought. In particular, it is non-trivial that the decays of the fields driving D-inflation can reheat the universe in such a way as to avoid the strong gravitino production constraints. We also show how the initial conditions for Affleck-Dine baryogenesis can arise in these models and that the simplest flat directions along which baryon number is generated can often be ruled out by the constraints coming from decoherence of the condensate in a hot environment. At the end, we find that successful reheating and baryogenesis can take place in a large subset of D-inflationary models.
[ { "created": "Thu, 19 Feb 1998 07:43:05 GMT", "version": "v1" } ]
2009-10-31
[ [ "Kolda", "Christopher", "", "IAS, Princeton" ], [ "March-Russell", "John", "", "IAS, Princeton" ] ]
The phenomenology of supersymmetric models of inflation, where the inflationary vacuum energy is dominated by D-terms of a U(1), is investigated. Particular attention is paid to the questions of how to arrange for sufficient e-folds of inflation to occur, what kind of thermal history is expected after the end of inflation, and how to implement successful baryogenesis. Such models are argued to require a more restrictive symmetry structure than previously thought. In particular, it is non-trivial that the decays of the fields driving D-inflation can reheat the universe in such a way as to avoid the strong gravitino production constraints. We also show how the initial conditions for Affleck-Dine baryogenesis can arise in these models and that the simplest flat directions along which baryon number is generated can often be ruled out by the constraints coming from decoherence of the condensate in a hot environment. At the end, we find that successful reheating and baryogenesis can take place in a large subset of D-inflationary models.
2003.03386
Sudip Jana
Sudip Jana, Vishnu P.K. and Shaikh Saad
Resolving electron and muon $g-2$ within the 2HDM
14 pages, 6 figures, matches published version
Phys. Rev. D 101, 115037 (2020)
10.1103/PhysRevD.101.115037
OSU-HEP-20-01
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent precise measurement of the electron anomalous magnetic moment (AMM) adds to the longstanding tension of the muon AMM and together strongly point towards physics beyond the Standard Model (BSM). In this work, we propose a solution to both anomalies in an economical fashion via a light scalar that emerges from a second Higgs doublet and resides in the $\mathcal{O}(10)$-MeV to $\mathcal{O}(1)$-GeV mass range yielding the right sizes and signs for these deviations due to one-loop and two-loop dominance for the muon and the electron, respectively. A scalar of this type is subject to a number of various experimental constraints, however, as we show, it can remain sufficiently light by evading all experimental bounds and has the great potential to be discovered in the near-future low-energy experiments. The analysis provided here is equally applicable to any BSM scenario for which a light scalar is allowed to have sizable flavor-diagonal couplings to the charged leptons. In addition to the light scalar, our theory predicts the existence of a nearly degenerate charged scalar and a pseudoscalar, which have masses of the order of the electroweak scale. We analyze possible ways to probe new-physics signals at colliders and find that this scenario can be tested at the LHC by looking at the novel process $pp \to H^\pm H^\pm jj \to l^\pm l^\pm j j + {E\!\!\!\!/}_{T}$ via same-sign pair production of charged Higgs bosons.
[ { "created": "Fri, 6 Mar 2020 19:00:05 GMT", "version": "v1" }, { "created": "Wed, 17 Jun 2020 13:44:45 GMT", "version": "v2" } ]
2020-06-30
[ [ "Jana", "Sudip", "" ], [ "K.", "Vishnu P.", "" ], [ "Saad", "Shaikh", "" ] ]
Recent precise measurement of the electron anomalous magnetic moment (AMM) adds to the longstanding tension of the muon AMM and together strongly point towards physics beyond the Standard Model (BSM). In this work, we propose a solution to both anomalies in an economical fashion via a light scalar that emerges from a second Higgs doublet and resides in the $\mathcal{O}(10)$-MeV to $\mathcal{O}(1)$-GeV mass range yielding the right sizes and signs for these deviations due to one-loop and two-loop dominance for the muon and the electron, respectively. A scalar of this type is subject to a number of various experimental constraints, however, as we show, it can remain sufficiently light by evading all experimental bounds and has the great potential to be discovered in the near-future low-energy experiments. The analysis provided here is equally applicable to any BSM scenario for which a light scalar is allowed to have sizable flavor-diagonal couplings to the charged leptons. In addition to the light scalar, our theory predicts the existence of a nearly degenerate charged scalar and a pseudoscalar, which have masses of the order of the electroweak scale. We analyze possible ways to probe new-physics signals at colliders and find that this scenario can be tested at the LHC by looking at the novel process $pp \to H^\pm H^\pm jj \to l^\pm l^\pm j j + {E\!\!\!\!/}_{T}$ via same-sign pair production of charged Higgs bosons.
hep-ph/9406246
null
Carl H. Albright and Satyanarayan Nandi
Comparison of SO(10)-Symmetric Fermion Mass Matrices with and without Degenerate Neutrinos
12 pages, FERMILAB-PUB-94/119-T and OSU Preprint 289, plain LaTeX
null
null
null
hep-ph
null
It has been recently suggested by others that one can simultaneously explain the depletions of solar electron-neutrinos and atmospheric muon-neutrinos along with a 7 eV neutrino component of mixed dark matter by postulating the existence of nearly-degenerate 2 eV neutrinos with the correct mixing parameters. We study this claim in the framework of a simple SO(10)-symmetric model constructed from the low scale data using a bottom-up procedure recently advanced by the authors and compare the results with and without degenerate neutrinos.
[ { "created": "Tue, 7 Jun 1994 18:45:47 GMT", "version": "v1" } ]
2007-05-23
[ [ "Albright", "Carl H.", "" ], [ "Nandi", "Satyanarayan", "" ] ]
It has been recently suggested by others that one can simultaneously explain the depletions of solar electron-neutrinos and atmospheric muon-neutrinos along with a 7 eV neutrino component of mixed dark matter by postulating the existence of nearly-degenerate 2 eV neutrinos with the correct mixing parameters. We study this claim in the framework of a simple SO(10)-symmetric model constructed from the low scale data using a bottom-up procedure recently advanced by the authors and compare the results with and without degenerate neutrinos.
hep-ph/0212188
Schweizer Julia
J. Schweizer (Bern University)
Explicit generating functional for pions and virtual photons
20 pages, 2 figures; version accepted for publication, minor typographical changes, acknowledgments added
JHEP 0302 (2003) 007
10.1088/1126-6708/2003/02/007
Preprint BUTP-02/13
hep-ph
null
We construct the explicit one-loop functional of chiral perturbation theory for two light flavours, including virtual photons. We stick to contributions where 1 or 2 mesons and at most one photon are running in the loops. With the explicit functional at hand, the evaluation of the relevant Green functions boils down to performing traces over the flavour matrices. For illustration, we work out the pi+ pi- -> pi0 pi0 scattering amplitude at threshold at order p^4, e^2p^2.
[ { "created": "Fri, 13 Dec 2002 12:17:25 GMT", "version": "v1" }, { "created": "Mon, 31 Mar 2003 10:38:49 GMT", "version": "v2" } ]
2009-11-07
[ [ "Schweizer", "J.", "", "Bern University" ] ]
We construct the explicit one-loop functional of chiral perturbation theory for two light flavours, including virtual photons. We stick to contributions where 1 or 2 mesons and at most one photon are running in the loops. With the explicit functional at hand, the evaluation of the relevant Green functions boils down to performing traces over the flavour matrices. For illustration, we work out the pi+ pi- -> pi0 pi0 scattering amplitude at threshold at order p^4, e^2p^2.
2306.02118
Leszek Motyka
Leszek Motyka and Mariusz Sadzikowski (Jagiellonian University)
Twist decomposition of non-linear effects in Balitsky-Kovchegov evolution of proton structure functions
21 pages, 3 figures, the final version published in European Physical Journal C
Eur.Phys.J.C 83 (2023) 11, 1062
10.1140/epjc/s10052-023-12241-z
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Effects of non-linear small-x evolution of the gluon distribution given by the Balitsky-Kovchegov equation are analyzed within the collinear approximation framework. We perform a twist decomposition of the proton structure functions F2 and FL obtained from the Balitsky-Kovchegov equation using the Mellin representation of the scattering cross-sections at high energies. In both the structure functions we find strong corrections coming from the non-linear effects in the gluon evolution at twist 2, and strongly suppressed higher twist effects. This implies that unitarization effects of high energy scattering amplitudes are mostly the leading twist effect. Furthermore we consider the double logarithmic limit of the Balitsky--Kovchegov equation for the collinear gluon distribution, and compare the result to the Gribov-Levin-Ryskin equation. We find that these two equations differ by two powers of the hard scale logarithm for the large scales.
[ { "created": "Sat, 3 Jun 2023 14:12:36 GMT", "version": "v1" }, { "created": "Thu, 7 Dec 2023 10:24:37 GMT", "version": "v2" } ]
2023-12-08
[ [ "Motyka", "Leszek", "", "Jagiellonian University" ], [ "Sadzikowski", "Mariusz", "", "Jagiellonian University" ] ]
Effects of non-linear small-x evolution of the gluon distribution given by the Balitsky-Kovchegov equation are analyzed within the collinear approximation framework. We perform a twist decomposition of the proton structure functions F2 and FL obtained from the Balitsky-Kovchegov equation using the Mellin representation of the scattering cross-sections at high energies. In both the structure functions we find strong corrections coming from the non-linear effects in the gluon evolution at twist 2, and strongly suppressed higher twist effects. This implies that unitarization effects of high energy scattering amplitudes are mostly the leading twist effect. Furthermore we consider the double logarithmic limit of the Balitsky--Kovchegov equation for the collinear gluon distribution, and compare the result to the Gribov-Levin-Ryskin equation. We find that these two equations differ by two powers of the hard scale logarithm for the large scales.
1605.07175
Hongxi Xing
Zhong-Bo Kang, Jian-Wei Qiu, Xin-Nian Wang, Hongxi Xing
Next-to-leading order transverse momentum broadening for Drell-Yan production in p+A collisions
18 pages, 12 figures
Phys. Rev. D 94, 074038 (2016)
10.1103/PhysRevD.94.074038
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the nuclear transverse momentum broadening for Drell-Yan lepton pair production in p+A collisions at next-to-leading order (NLO) in powers of strong coupling constant $\alpha_s$. We verify that the transverse momentum weighted differential cross section in NLO perturbative QCD (pQCD) at twist-4 can be factorized into the convolution of parton distribution function of an active parton in the projectile proton, a twist-4 multiparton correlation function of the target nucleus, and perturbatively calculable hard coefficient function. We identify a QCD evolution equation for such a twist-4 nuclear gluon-quark correlation function, and verify its universality -- its process independence. This finding demonstrates the prediction power of pQCD factorization approach for studying parton multiple scattering in nuclear medium.
[ { "created": "Mon, 23 May 2016 20:00:00 GMT", "version": "v1" } ]
2016-11-02
[ [ "Kang", "Zhong-Bo", "" ], [ "Qiu", "Jian-Wei", "" ], [ "Wang", "Xin-Nian", "" ], [ "Xing", "Hongxi", "" ] ]
We present the nuclear transverse momentum broadening for Drell-Yan lepton pair production in p+A collisions at next-to-leading order (NLO) in powers of strong coupling constant $\alpha_s$. We verify that the transverse momentum weighted differential cross section in NLO perturbative QCD (pQCD) at twist-4 can be factorized into the convolution of parton distribution function of an active parton in the projectile proton, a twist-4 multiparton correlation function of the target nucleus, and perturbatively calculable hard coefficient function. We identify a QCD evolution equation for such a twist-4 nuclear gluon-quark correlation function, and verify its universality -- its process independence. This finding demonstrates the prediction power of pQCD factorization approach for studying parton multiple scattering in nuclear medium.
1305.5835
Richard Bonventre
R. Bonventre, A. LaTorre, J.R. Klein, G.D. Orebi Gann, S. Seibert, O. Wasalski
Non-Standard Models, Solar Neutrinos, and Large \theta_{13}
null
null
10.1103/PhysRevD.88.053010
null
hep-ph hep-ex nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Solar neutrino experiments have yet to see directly the transition region between matter-enhanced and vacuum oscillations. The transition region is particularly sensitive to models of non-standard neutrino interactions and propagation. We examine several such non-standard models, which predict a lower-energy transition region and a flatter survival probability for the ^{8}B solar neutrinos than the standard large-mixing angle (LMA) model. We find that while some of the non-standard models provide a better fit to the solar neutrino data set, the large measured value of \theta_{13} and the size of the experimental uncertainties lead to a low statistical significance for these fits. We have also examined whether simple changes to the solar density profile can lead to a flatter ^{8}B survival probability than the LMA prediction, but find that this is not the case for reasonable changes. We conclude that the data in this critical region is still too poor to determine whether any of these models, or LMA, is the best description of the data.
[ { "created": "Fri, 24 May 2013 19:40:56 GMT", "version": "v1" } ]
2015-06-16
[ [ "Bonventre", "R.", "" ], [ "LaTorre", "A.", "" ], [ "Klein", "J. R.", "" ], [ "Gann", "G. D. Orebi", "" ], [ "Seibert", "S.", "" ], [ "Wasalski", "O.", "" ] ]
Solar neutrino experiments have yet to see directly the transition region between matter-enhanced and vacuum oscillations. The transition region is particularly sensitive to models of non-standard neutrino interactions and propagation. We examine several such non-standard models, which predict a lower-energy transition region and a flatter survival probability for the ^{8}B solar neutrinos than the standard large-mixing angle (LMA) model. We find that while some of the non-standard models provide a better fit to the solar neutrino data set, the large measured value of \theta_{13} and the size of the experimental uncertainties lead to a low statistical significance for these fits. We have also examined whether simple changes to the solar density profile can lead to a flatter ^{8}B survival probability than the LMA prediction, but find that this is not the case for reasonable changes. We conclude that the data in this critical region is still too poor to determine whether any of these models, or LMA, is the best description of the data.
1611.05857
Thomas Rink
Thomas Rink and Kai Schmitz
Perturbed Yukawa Textures in the Minimal Seesaw Model
30 pages, 7 figures, 2 tables; v2: updated references, extended discussion in the introduction and conclusions, new title, results unchanged, content matches version published in JHEP
null
10.1007/JHEP03(2017)158
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
\noindent We revisit the \textit{minimal seesaw model}, i.e., the type-I seesaw mechanism involving only two right-handed neutrinos. % This model represents an important minimal benchmark scenario for future experimental updates on neutrino oscillations. % It features four real parameters that cannot be fixed by the current data: two $CP$-violating phases, $\delta$ and $\sigma$, as well as one complex parameter, $z$, that is experimentally inaccessible at low energies. % The parameter $z$ controls the structure of the neutrino Yukawa matrix at high energies, which is why it may be regarded as a label or index for all UV completions of the minimal seesaw model. % The fact that $z$ encompasses only two real degrees of freedom allows us to systematically scan the minimal seesaw model over all of its possible UV completions. % In doing so, we address the following question: Suppose $\delta$ and $\sigma$ should be measured at particular values in the future---to what extent is one then still able to realize approximate textures in the neutrino Yukawa matrix? % Our analysis, thus, generalizes previous studies of the minimal seesaw model based on the assumption of exact texture zeros. % In particular, our study allows us to assess the theoretical uncertainty inherent to the common texture ansatz. % One of our main results is that a normal light-neutrino mass hierarchy is, in fact, still consistent with a two-zero Yukawa texture, provided that the two texture zeros receive corrections at the level of $\mathcal{O}\left(\textrm{10}\,\%\right)$. % While our numerical results pertain to the minimal seesaw model only, our general procedure appears to be applicable to other neutrino mass models as well.
[ { "created": "Thu, 17 Nov 2016 20:59:11 GMT", "version": "v1" }, { "created": "Tue, 4 Apr 2017 07:44:10 GMT", "version": "v2" } ]
2017-04-05
[ [ "Rink", "Thomas", "" ], [ "Schmitz", "Kai", "" ] ]
\noindent We revisit the \textit{minimal seesaw model}, i.e., the type-I seesaw mechanism involving only two right-handed neutrinos. % This model represents an important minimal benchmark scenario for future experimental updates on neutrino oscillations. % It features four real parameters that cannot be fixed by the current data: two $CP$-violating phases, $\delta$ and $\sigma$, as well as one complex parameter, $z$, that is experimentally inaccessible at low energies. % The parameter $z$ controls the structure of the neutrino Yukawa matrix at high energies, which is why it may be regarded as a label or index for all UV completions of the minimal seesaw model. % The fact that $z$ encompasses only two real degrees of freedom allows us to systematically scan the minimal seesaw model over all of its possible UV completions. % In doing so, we address the following question: Suppose $\delta$ and $\sigma$ should be measured at particular values in the future---to what extent is one then still able to realize approximate textures in the neutrino Yukawa matrix? % Our analysis, thus, generalizes previous studies of the minimal seesaw model based on the assumption of exact texture zeros. % In particular, our study allows us to assess the theoretical uncertainty inherent to the common texture ansatz. % One of our main results is that a normal light-neutrino mass hierarchy is, in fact, still consistent with a two-zero Yukawa texture, provided that the two texture zeros receive corrections at the level of $\mathcal{O}\left(\textrm{10}\,\%\right)$. % While our numerical results pertain to the minimal seesaw model only, our general procedure appears to be applicable to other neutrino mass models as well.
1812.05263
Balbeer Singh
Balbeer Singh, Aman Abhishek, Santosh K Das, Hiranmaya Mishra
Heavy quark diffusion in a Polyakov loop plasma
22 pages, 11 figures
Phys. Rev. D 100, 114019 (2019)
10.1103/PhysRevD.100.114019
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the transport coefficients, drag and momentum diffusion, of a heavy quark in a thermalized plasma of light quarks in the background of Polyakov loop. Quark thermal mass and the gluon Debye mass are calculated in a non-trivial Polyakov loop background. The constituent quark masses and the Polyakov loop is estimated within a Polyakov loop quark meson (PQM) model. The relevant scattering amplitudes for heavy quark and light partons in the background of Polyakov loop has been estimated within the matrix model. We have also compared the results with the Polyakov loop parameter estimated from lattice QCD simulations. We have studied the temperature and momentum dependence of heavy quark drag and diffusion coefficients. It is observed that the temperature dependence of the drag coefficient is quite weak which may play a key role to understand heavy quark observables at RHIC and LHC energies.
[ { "created": "Thu, 13 Dec 2018 05:04:02 GMT", "version": "v1" }, { "created": "Sun, 13 Oct 2019 13:46:33 GMT", "version": "v2" } ]
2019-12-18
[ [ "Singh", "Balbeer", "" ], [ "Abhishek", "Aman", "" ], [ "Das", "Santosh K", "" ], [ "Mishra", "Hiranmaya", "" ] ]
We calculate the transport coefficients, drag and momentum diffusion, of a heavy quark in a thermalized plasma of light quarks in the background of Polyakov loop. Quark thermal mass and the gluon Debye mass are calculated in a non-trivial Polyakov loop background. The constituent quark masses and the Polyakov loop is estimated within a Polyakov loop quark meson (PQM) model. The relevant scattering amplitudes for heavy quark and light partons in the background of Polyakov loop has been estimated within the matrix model. We have also compared the results with the Polyakov loop parameter estimated from lattice QCD simulations. We have studied the temperature and momentum dependence of heavy quark drag and diffusion coefficients. It is observed that the temperature dependence of the drag coefficient is quite weak which may play a key role to understand heavy quark observables at RHIC and LHC energies.
hep-ph/0009346
Csli
Ya Sheng Yang (PKU) and Chong Sheng Li (PKU)
Electroweak Corrections to the Deacy $H^+\to W^+h$ in the Minimal Supersymmetric Model
20 pages, including 7 ps figures
Phys.Lett.B497:101-110,2001
10.1016/S0370-2693(00)01306-X
PKU-TH-2000-98
hep-ph
null
We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew} m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the process $H^+\to W^+h$ in the Minimal Supersymmetric Model. These corrections arise from the virtual effects of the third family quaurks (top and bottom) and squarks (top-squark and bottom-squark). We find that for $m_{H^+}>200$GeV at low $\tan\beta(\leq 3)$, the corrections can increase the tree-level decay widths and the branching radios more than 20% and 40%, respectively.
[ { "created": "Fri, 29 Sep 2000 11:49:31 GMT", "version": "v1" } ]
2014-11-17
[ [ "Yang", "Ya Sheng", "", "PKU" ], [ "Li", "Chong Sheng", "", "PKU" ] ]
We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew} m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the process $H^+\to W^+h$ in the Minimal Supersymmetric Model. These corrections arise from the virtual effects of the third family quaurks (top and bottom) and squarks (top-squark and bottom-squark). We find that for $m_{H^+}>200$GeV at low $\tan\beta(\leq 3)$, the corrections can increase the tree-level decay widths and the branching radios more than 20% and 40%, respectively.
1205.1689
Ahmed Ali
Ahmed Ali (DESY), Fernando Barreiro (UAM, Madrid), Javier Llorente (UAM, Madrid), Wei Wang (DESY)
Transverse Energy-Energy Correlations in Next-to-Leading Order in $\alpha_s$ at the LHC
12 pages, 8 figures, several added references; computed a number of parametric and PDF uncertainties and quantified the sensitivity of the correlations to alpha_s(M_Z); version to appear in Physical Review D
null
10.1103/PhysRevD.86.114017
DESY 12-063; FTUAM-2012-10
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the transverse energy-energy correlation (EEC) and its asymmetry (AEEC) in next-to-leading order (NLO) in $\alpha_s$ in proton-proton collisions at the LHC with the center-of-mass energy $E_{\rm c.m.}=7$ TeV. We show that the transverse EEC and the AEEC distributions are insensitive to the QCD factorization- and the renormalization-scales, structure functions of the proton, and for a judicious choice of the jet-size, also the underlying minimum bias events. Hence they can be used to precisely test QCD in hadron colliders and determine the strong coupling $\alpha_s$. We illustrate these features by defining the hadron jets using the anti-$k_T$ jet algorithm and an event selection procedure employed in the analysis of jets at the LHC and show the $\alpha_s(M_Z)$-dependence of the transverse EEC and the AEEC in the anticipated range $0.11 \leq \alpha_s(M_Z) \leq 0.13$.
[ { "created": "Tue, 8 May 2012 13:18:09 GMT", "version": "v1" }, { "created": "Wed, 28 Nov 2012 12:01:18 GMT", "version": "v2" } ]
2015-06-05
[ [ "Ali", "Ahmed", "", "DESY" ], [ "Barreiro", "Fernando", "", "UAM, Madrid" ], [ "Llorente", "Javier", "", "UAM, Madrid" ], [ "Wang", "Wei", "", "DESY" ] ]
We compute the transverse energy-energy correlation (EEC) and its asymmetry (AEEC) in next-to-leading order (NLO) in $\alpha_s$ in proton-proton collisions at the LHC with the center-of-mass energy $E_{\rm c.m.}=7$ TeV. We show that the transverse EEC and the AEEC distributions are insensitive to the QCD factorization- and the renormalization-scales, structure functions of the proton, and for a judicious choice of the jet-size, also the underlying minimum bias events. Hence they can be used to precisely test QCD in hadron colliders and determine the strong coupling $\alpha_s$. We illustrate these features by defining the hadron jets using the anti-$k_T$ jet algorithm and an event selection procedure employed in the analysis of jets at the LHC and show the $\alpha_s(M_Z)$-dependence of the transverse EEC and the AEEC in the anticipated range $0.11 \leq \alpha_s(M_Z) \leq 0.13$.
0710.4504
Thomas A. Trainor
Thomas A. Trainor
Centrality evolution of $p_t$ and $y_t$ spectra from Au-Au collisions at $\sqrt{s_{NN}} = 200$ GeV
21 pages, 18 figures
Int.J.Mod.Phys.E17:1499-1540,2008
10.1142/S021830130801057X
null
hep-ph
null
A two-component analysis of spectra to $p_t = 12$ GeV/c for identified pions and protons from 200 GeV Au-Au collisions is presented. The method is similar to an analysis of the $n_{ch}$ dependence of $p_t$ spectra from p-p collisions at 200 GeV, but applied to Au-Au centrality dependence. The soft-component reference is a L\'evy distribution on transverse mass $m_t$. The hard-component reference is a Gaussian on $y_t$ with exponential ($p_t$ power-law) tail. Deviations of data from the reference are described by hard-component ratio $r_{AA}$ which generalizes nuclear modification factor $R_{AA}$. The analysis suggests that centrality evolution of pion and proton spectra is dominated by changes in parton fragmentation. The structure of $r_{AA}$ suggests that parton energy loss produces a negative boost $\Delta y_t$ of a large fraction (but not all) of the minimum-bias fragment distribution, and that lower-energy partons suffer relatively less energy loss, possibly due to color screening. The analysis also suggests that the anomalous $p/\pi$ ratio may be due to differences in the parton energy-loss process experienced by the two hadron species. This analysis provides no evidence for radial flow.
[ { "created": "Wed, 24 Oct 2007 16:19:01 GMT", "version": "v1" } ]
2008-11-26
[ [ "Trainor", "Thomas A.", "" ] ]
A two-component analysis of spectra to $p_t = 12$ GeV/c for identified pions and protons from 200 GeV Au-Au collisions is presented. The method is similar to an analysis of the $n_{ch}$ dependence of $p_t$ spectra from p-p collisions at 200 GeV, but applied to Au-Au centrality dependence. The soft-component reference is a L\'evy distribution on transverse mass $m_t$. The hard-component reference is a Gaussian on $y_t$ with exponential ($p_t$ power-law) tail. Deviations of data from the reference are described by hard-component ratio $r_{AA}$ which generalizes nuclear modification factor $R_{AA}$. The analysis suggests that centrality evolution of pion and proton spectra is dominated by changes in parton fragmentation. The structure of $r_{AA}$ suggests that parton energy loss produces a negative boost $\Delta y_t$ of a large fraction (but not all) of the minimum-bias fragment distribution, and that lower-energy partons suffer relatively less energy loss, possibly due to color screening. The analysis also suggests that the anomalous $p/\pi$ ratio may be due to differences in the parton energy-loss process experienced by the two hadron species. This analysis provides no evidence for radial flow.
2105.09944
Zurab Silagadze
Abdaljalel Alizzi and Z.K. Silagadze
Ultralight dark photon and Casimir effect
20 pages, no figures, revtex4. Version to be published in International Journal of Theoretical Physics
Int. J. Theor. Phys. 61 (2022), 43
10.1007/s10773-022-05034-9
null
hep-ph hep-th quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the influence of a dark photon on the Casimir effect and calculate the corresponding leading contribution to the Casimir energy. For expected magnitudes of the photon - dark photon mixing parameter, the influence turns out to be negligible. The plasmon dispersion relation is also not noticeably modified by the presence of a dark photon.
[ { "created": "Thu, 20 May 2021 13:31:29 GMT", "version": "v1" }, { "created": "Tue, 25 Jan 2022 13:09:32 GMT", "version": "v2" } ]
2022-02-23
[ [ "Alizzi", "Abdaljalel", "" ], [ "Silagadze", "Z. K.", "" ] ]
We investigate the influence of a dark photon on the Casimir effect and calculate the corresponding leading contribution to the Casimir energy. For expected magnitudes of the photon - dark photon mixing parameter, the influence turns out to be negligible. The plasmon dispersion relation is also not noticeably modified by the presence of a dark photon.
hep-ph/9901318
Carl H. Albright
Carl H. Albright (Northern Illinois U./Fermilab), S.M. Barr (Bartol Research Institute)
Predicting quark and lepton masses and mixings
15 pages, LaTeX
Phys.Lett.B452:287-293,1999
10.1016/S0370-2693(99)00290-7
BA-99-05, FERMILAB-Pub-99/007-T
hep-ph
null
A model is presented that fits the quark and lepton masses and mixings wherein five dimensionless parameters and a phase account for fifteen dimensionless observables. Among these are the Wolfenstein parameters $\rho$ and $\eta$, the $\nu_e-\nu_{\mu}$ and $\nu_e-\nu_{\tau}$ mixing angles which are predicted to be small and comparable while the $\nu_{\mu}-\nu_{\tau}$ mixing angle is predicted to be large. The model is based on supersymmetric SO(10) with the form of the mass matrices motivated by simplicity at the level of grand unification.
[ { "created": "Thu, 14 Jan 1999 23:02:33 GMT", "version": "v1" } ]
2011-05-12
[ [ "Albright", "Carl H.", "", "Northern Illinois U./Fermilab" ], [ "Barr", "S. M.", "", "Bartol\n Research Institute" ] ]
A model is presented that fits the quark and lepton masses and mixings wherein five dimensionless parameters and a phase account for fifteen dimensionless observables. Among these are the Wolfenstein parameters $\rho$ and $\eta$, the $\nu_e-\nu_{\mu}$ and $\nu_e-\nu_{\tau}$ mixing angles which are predicted to be small and comparable while the $\nu_{\mu}-\nu_{\tau}$ mixing angle is predicted to be large. The model is based on supersymmetric SO(10) with the form of the mass matrices motivated by simplicity at the level of grand unification.
2404.16090
Yong Xu
Basabendu Barman, Nicol\'as Bernal, Yong Xu
Resonant Reheating
v1:28 pages, 11 figures; v2: minor modification, version accepted for publication in JCAP
null
null
MITP-24-045
hep-ph astro-ph.CO
http://creativecommons.org/licenses/by/4.0/
We investigate a novel reheating scenario proceeding through $s$-channel inflaton annihilation, mediated by a massive scalar. If the inflaton $\phi$ oscillates around the minimum of a monomial potential $\propto \phi^{n}$, we reveal the emergence of resonance phenomena originating from the dynamic evolution of the inflaton mass for $n>2$. Consequently, a resonance appears in both the radiation and the temperature evolution during the reheating process. By solving the coupled Boltzmann equations, we present solutions for radiation and temperature. We find non-trivial temperature characteristics during reheating, depending on the value of $n$ and the masses of the inflaton and mediator. Some phenomenological aspects of the model are explored. As a concrete example, we show that the same mediator participates in the genesis of dark matter, modifying the standard freeze-in dynamics. In addition, we demonstrate that the resonant reheating scenario could be tested by next-generation low- and high-frequency gravitational wave detectors.
[ { "created": "Wed, 24 Apr 2024 18:00:01 GMT", "version": "v1" }, { "created": "Mon, 29 Jul 2024 07:36:51 GMT", "version": "v2" } ]
2024-07-30
[ [ "Barman", "Basabendu", "" ], [ "Bernal", "Nicolás", "" ], [ "Xu", "Yong", "" ] ]
We investigate a novel reheating scenario proceeding through $s$-channel inflaton annihilation, mediated by a massive scalar. If the inflaton $\phi$ oscillates around the minimum of a monomial potential $\propto \phi^{n}$, we reveal the emergence of resonance phenomena originating from the dynamic evolution of the inflaton mass for $n>2$. Consequently, a resonance appears in both the radiation and the temperature evolution during the reheating process. By solving the coupled Boltzmann equations, we present solutions for radiation and temperature. We find non-trivial temperature characteristics during reheating, depending on the value of $n$ and the masses of the inflaton and mediator. Some phenomenological aspects of the model are explored. As a concrete example, we show that the same mediator participates in the genesis of dark matter, modifying the standard freeze-in dynamics. In addition, we demonstrate that the resonant reheating scenario could be tested by next-generation low- and high-frequency gravitational wave detectors.
2209.13795
Biaogang Wu
Biaogang Wu, Zhanduo Tang, Min He, Ralf Rapp
Charmonium, $B_c$ and X(3872) Transport at the LHC
null
null
10.1051/epjconf/202327602001
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
We deploy a kinetic-rate equation to evaluate the transport of $J/\psi$, $\psi(2S)$, $B_c$ and X(3872) in ultra-relativistic heavy-ion collisions and compare their production yields to experimental data from the Large Hadron Collider. The rate equation has two main transport parameters, i.e., the equilibrium limit and reaction rate for each state. The temperature-dependent equilibrium limits include charm- and bottom-quark fugacities based on their initial production. The reaction rates for charmonia, bottomonia and $B_c$ rely on charm- and bottom-quark masses as well as binding energies from a thermodynamic $T$-matrix approach. For the X(3872) particle, its internal structure information is encoded in reaction rates and initial conditions in the hadronic phase via two different scenarios: a loosely bound hadronic molecule vs. a compact diquark-antidiquark tetraquark.
[ { "created": "Wed, 28 Sep 2022 02:56:45 GMT", "version": "v1" } ]
2023-03-22
[ [ "Wu", "Biaogang", "" ], [ "Tang", "Zhanduo", "" ], [ "He", "Min", "" ], [ "Rapp", "Ralf", "" ] ]
We deploy a kinetic-rate equation to evaluate the transport of $J/\psi$, $\psi(2S)$, $B_c$ and X(3872) in ultra-relativistic heavy-ion collisions and compare their production yields to experimental data from the Large Hadron Collider. The rate equation has two main transport parameters, i.e., the equilibrium limit and reaction rate for each state. The temperature-dependent equilibrium limits include charm- and bottom-quark fugacities based on their initial production. The reaction rates for charmonia, bottomonia and $B_c$ rely on charm- and bottom-quark masses as well as binding energies from a thermodynamic $T$-matrix approach. For the X(3872) particle, its internal structure information is encoded in reaction rates and initial conditions in the hadronic phase via two different scenarios: a loosely bound hadronic molecule vs. a compact diquark-antidiquark tetraquark.
hep-ph/9506404
Jake Lee
C. S. Kim and Jake Lee
Large $p_T$ Hadroproduction of $Z$ as a Probe of Gluon Distribution inside Proton
(a) 13 pages(LaTeX) + 1 figure ps file(3 pages):compressed, uuencoded (b) accepted by Phys.Lett.B. (c) some figures are combined and one is omitted. (d) conclusion part is included into abstract
Phys.Lett. B366 (1996) 293
10.1016/0370-2693(95)01315-6
YUMS 95-014, SNUTP 95-053
hep-ph
null
The transverse momentum distribution of single vector boson production at hadron colliders provides useful ways of testing the Standard Model and searching new physics beyond the Standard Model. We study large $p_{_T}$ hadroproduction of $Z$-boson as a probe of gluon distributions inside proton. We investigate how to get initial gluon-involving contributions, or how to subtract quark-quark (or -antiquark) contributions from total cross section. We also investigated the simultaneous measurement of the rapidity and the transverse momentum of the produced $Z$ boson, to obtain momentum fractions of initial partons. And we extracted relevant uncertainties involving in experimental and theoretical analyses. This large $p_{_T}$ hadroproduction of $Z$ can be used as constraints on analyses of global parton (gluon and quarks) distribution functions inside proton.
[ { "created": "Fri, 23 Jun 1995 12:51:06 GMT", "version": "v1" }, { "created": "Tue, 24 Oct 1995 06:05:34 GMT", "version": "v2" } ]
2009-10-28
[ [ "Kim", "C. S.", "" ], [ "Lee", "Jake", "" ] ]
The transverse momentum distribution of single vector boson production at hadron colliders provides useful ways of testing the Standard Model and searching new physics beyond the Standard Model. We study large $p_{_T}$ hadroproduction of $Z$-boson as a probe of gluon distributions inside proton. We investigate how to get initial gluon-involving contributions, or how to subtract quark-quark (or -antiquark) contributions from total cross section. We also investigated the simultaneous measurement of the rapidity and the transverse momentum of the produced $Z$ boson, to obtain momentum fractions of initial partons. And we extracted relevant uncertainties involving in experimental and theoretical analyses. This large $p_{_T}$ hadroproduction of $Z$ can be used as constraints on analyses of global parton (gluon and quarks) distribution functions inside proton.
0905.2309
Peter Klimai
E.V. Bugaev, P.A. Klimai
About possible contribution of intrinsic charm component to inclusive spectra of charmed mesons
10 pages, 4 figures. Version published in J. Phys. G.
J.Phys.G 37:055004,2010
10.1088/0954-3899/37/5/055004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate differential energy spectra ($x_F$-distributions) of charmed particles produced in proton-nucleus collisions, assuming the existence of intrinsic heavy quark components in the proton wave function. For the calculation, the recently proposed factorization scheme is used, based on the Color Glass Condensate theory and specially suited for predictions of a production of particles with large rapidities. It is argued that the intrinsic charm component can, if it exists, dominate in a sum of two components, intrinsic + extrinsic, of the inclusive spectrum of charmed particles produced in proton-nucleus collisions at high energies, in the region of medium $x_F$, $0.15 < x_F < 0.7$, and can give noticeable contribution to atmospheric fluxes of prompt muons and neutrinos.
[ { "created": "Thu, 14 May 2009 11:43:38 GMT", "version": "v1" }, { "created": "Thu, 1 Apr 2010 09:27:17 GMT", "version": "v2" } ]
2015-03-13
[ [ "Bugaev", "E. V.", "" ], [ "Klimai", "P. A.", "" ] ]
We calculate differential energy spectra ($x_F$-distributions) of charmed particles produced in proton-nucleus collisions, assuming the existence of intrinsic heavy quark components in the proton wave function. For the calculation, the recently proposed factorization scheme is used, based on the Color Glass Condensate theory and specially suited for predictions of a production of particles with large rapidities. It is argued that the intrinsic charm component can, if it exists, dominate in a sum of two components, intrinsic + extrinsic, of the inclusive spectrum of charmed particles produced in proton-nucleus collisions at high energies, in the region of medium $x_F$, $0.15 < x_F < 0.7$, and can give noticeable contribution to atmospheric fluxes of prompt muons and neutrinos.
1506.00766
Hua-Xing Chen
Dan Zhou, Hua-Xing Chen, Li-Sheng Geng, Xiang Liu and Shi-Lin Zhu
F-wave heavy-light meson spectroscopy in QCD sum rules and heavy quark effective theory
10 pages, 8 figures, 3 tables, accepted by PRD
Phys. Rev. D 92, 114015 (2015)
10.1103/PhysRevD.92.114015
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the F-wave c_bar s heavy meson doublets (2+,3+) and (3+,4+). They have large orbital excitations L=3, and may be good challenges (tests) for theoretical studies. To study them we use the method of QCD sum rule in the framework of heavy quark effective theory. Their masses are predicted to be m_{(2+,3+)} = (3.45 \pm 0.25, 3.50 \pm 0.26) GeV and m_{(3+,4+)} = (3.20 \pm 0.22, 3.26 \pm 0.23) GeV, with mass splittings Delta m_{(2+,3+)} = m_{3+} - m_{2+} = 0.046 \pm 0.030 GeV and Delta m_{(3+,4+)} = 0.053 \pm 0.044 GeV, respectively. We note that this is a pioneering work and these results are provisional.
[ { "created": "Tue, 2 Jun 2015 06:32:39 GMT", "version": "v1" }, { "created": "Sat, 21 Nov 2015 06:51:58 GMT", "version": "v2" } ]
2015-12-14
[ [ "Zhou", "Dan", "" ], [ "Chen", "Hua-Xing", "" ], [ "Geng", "Li-Sheng", "" ], [ "Liu", "Xiang", "" ], [ "Zhu", "Shi-Lin", "" ] ]
We study the F-wave c_bar s heavy meson doublets (2+,3+) and (3+,4+). They have large orbital excitations L=3, and may be good challenges (tests) for theoretical studies. To study them we use the method of QCD sum rule in the framework of heavy quark effective theory. Their masses are predicted to be m_{(2+,3+)} = (3.45 \pm 0.25, 3.50 \pm 0.26) GeV and m_{(3+,4+)} = (3.20 \pm 0.22, 3.26 \pm 0.23) GeV, with mass splittings Delta m_{(2+,3+)} = m_{3+} - m_{2+} = 0.046 \pm 0.030 GeV and Delta m_{(3+,4+)} = 0.053 \pm 0.044 GeV, respectively. We note that this is a pioneering work and these results are provisional.
hep-ph/9903386
Jonathan R. Ellis
John Ellis and N.E. Mavromatos
Comments on CP, T and CPT Violation in Neutral Kaon Decays
20 pages LaTeX, Contribution to the Festschrift for L.B. Okun, to appear in a special issue of Physics Reports, eds. V.L. Telegdi and K. Winter
Phys.Rept.320:341-354,1999
10.1016/S0370-1573(99)00058-7
CERN-TH/99-60, OUTP-99-17P
hep-ph hep-ex hep-th
null
We comment on CP, T and CPT violation in the light of interesting new data from the CPLEAR and KTeV Collaborations on neutral kaon decay asymmetries. Other recent data from the CPLEAR experiment, constraining possible violations of CPT and the $\Delta S = \Delta Q$ rule, exclude the possibility that the semileptonic-decay asymmetry $A_{T}$ measured by CPLEAR could be solely due to CPT violation, confirming that their data constitute direct evidence for T violation. The CP-violating asymmetry in $K_L \to e^-e^+\pi^-\pi^+$ recently measured by the KTeV Collaboration does not by itself provide direct evidence for T violation, but we use it to place new bounds on CPT violation.
[ { "created": "Wed, 17 Mar 1999 16:51:08 GMT", "version": "v1" } ]
2009-09-11
[ [ "Ellis", "John", "" ], [ "Mavromatos", "N. E.", "" ] ]
We comment on CP, T and CPT violation in the light of interesting new data from the CPLEAR and KTeV Collaborations on neutral kaon decay asymmetries. Other recent data from the CPLEAR experiment, constraining possible violations of CPT and the $\Delta S = \Delta Q$ rule, exclude the possibility that the semileptonic-decay asymmetry $A_{T}$ measured by CPLEAR could be solely due to CPT violation, confirming that their data constitute direct evidence for T violation. The CP-violating asymmetry in $K_L \to e^-e^+\pi^-\pi^+$ recently measured by the KTeV Collaboration does not by itself provide direct evidence for T violation, but we use it to place new bounds on CPT violation.
1001.2693
Brent D. Nelson
P. Nath, B.D. Nelson, H. Davoudiasl, B. Dutta, D. Feldman, Z. Liu, T. Han, P. Langacker, R. Mohapatra, J. Valle, A. Pilaftsis, D. Zerwas, S. AbdusSalam, C. Adam-Bourdarios, J.A. Aguilar-Saavedra, B. Allanach, B. Altunkaynak, L.A. Anchordoqui, H. Baer, B. Bajc, O. Buchmueller, M. Carena, R. Cavanaugh, S. Chang, K. Choi, C. Csaki, S. Dawson, F. de Campos, A. De Roeck, M. Duhrssen, O.J.P. Eboli, J.R. Ellis, H. Flacher, H. Goldberg, W. Grimus, U. Haisch, S. Heinemeyer, M. Hirsch, M. Holmes, T. Ibrahim, G. Isidori, G. Kane, K. Kong, R. Lafaye, G. Landsberg, L. Lavoura, J.S. Lee, S.J. Lee, M. Lisanti, D. Lust, M.B. Magro, R. Mahbubani, M. Malinsky, F. Maltoni, S. Morisi, M.M. Muhlleitner, B. Mukhopadhyaya, M. Neubert, K.A. Olive, G. Perez, P. Fileviez Perez, T. Plehn, E. Ponton, W. Porod, F. Quevedo, M. Rauch, D. Restrepo, T.G. Rizzo, J.C. Romao, F.J. Ronga, J. Santiago, J. Schechter, G. Senjanovic, J. Shao, M. Spira, S. Stieberger, Z. Sullivan, T.M.P. Tait, X. Tata, T.R. Taylor, M. Toharia, J. Wacker, C.E.M. Wagner, L.-T. Wang, G. Weiglein, D. Zeppenfeld, K. Zurek
The Hunt for New Physics at the Large Hadron Collider
Summary document for international workshop "Beyond the Standard Model at the LHC" (Pre-SUSY09), Northeastern University, Boston, June 2-4, 2009
Nucl.Phys.Proc.Suppl.200-202:185-417,2010
10.1016/j.nuclphysbps.2010.03.001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Large Hadron Collider presents an unprecedented opportunity to probe the realm of new physics in the TeV region and shed light on some of the core unresolved issues of particle physics. These include the nature of electroweak symmetry breaking, the origin of mass, the possible constituent of cold dark matter, new sources of CP violation needed to explain the baryon excess in the universe, the possible existence of extra gauge groups and extra matter, and importantly the path Nature chooses to resolve the hierarchy problem - is it supersymmetry or extra dimensions. Many models of new physics beyond the standard model contain a hidden sector which can be probed at the LHC. Additionally, the LHC will be a top factory and accurate measurements of the properties of the top and its rare decays will provide a window to new physics. Further, the LHC could shed light on the origin of neutralino masses if the new physics associated with their generation lies in the TeV region. Finally, the LHC is also a laboratory to test the hypothesis of TeV scale strings and D-brane models. An overview of these possibilities is presented in the spirit that it will serve as a companion to the Technical Design Reports (TDRs) by the particle detector groups ATLAS and CMS to facilitate the test of the new theoretical ideas at the LHC. Which of these ideas stands the test of the LHC data will govern the course of particle physics in the subsequent decades.
[ { "created": "Thu, 14 Jan 2010 23:03:49 GMT", "version": "v1" } ]
2014-11-20
[ [ "Nath", "P.", "" ], [ "Nelson", "B. D.", "" ], [ "Davoudiasl", "H.", "" ], [ "Dutta", "B.", "" ], [ "Feldman", "D.", "" ], [ "Liu", "Z.", "" ], [ "Han", "T.", "" ], [ "Langacker", "P.", "" ], [ "Mohapatra", "R.", "" ], [ "Valle", "J.", "" ], [ "Pilaftsis", "A.", "" ], [ "Zerwas", "D.", "" ], [ "AbdusSalam", "S.", "" ], [ "Adam-Bourdarios", "C.", "" ], [ "Aguilar-Saavedra", "J. A.", "" ], [ "Allanach", "B.", "" ], [ "Altunkaynak", "B.", "" ], [ "Anchordoqui", "L. A.", "" ], [ "Baer", "H.", "" ], [ "Bajc", "B.", "" ], [ "Buchmueller", "O.", "" ], [ "Carena", "M.", "" ], [ "Cavanaugh", "R.", "" ], [ "Chang", "S.", "" ], [ "Choi", "K.", "" ], [ "Csaki", "C.", "" ], [ "Dawson", "S.", "" ], [ "de Campos", "F.", "" ], [ "De Roeck", "A.", "" ], [ "Duhrssen", "M.", "" ], [ "Eboli", "O. J. P.", "" ], [ "Ellis", "J. R.", "" ], [ "Flacher", "H.", "" ], [ "Goldberg", "H.", "" ], [ "Grimus", "W.", "" ], [ "Haisch", "U.", "" ], [ "Heinemeyer", "S.", "" ], [ "Hirsch", "M.", "" ], [ "Holmes", "M.", "" ], [ "Ibrahim", "T.", "" ], [ "Isidori", "G.", "" ], [ "Kane", "G.", "" ], [ "Kong", "K.", "" ], [ "Lafaye", "R.", "" ], [ "Landsberg", "G.", "" ], [ "Lavoura", "L.", "" ], [ "Lee", "J. S.", "" ], [ "Lee", "S. J.", "" ], [ "Lisanti", "M.", "" ], [ "Lust", "D.", "" ], [ "Magro", "M. B.", "" ], [ "Mahbubani", "R.", "" ], [ "Malinsky", "M.", "" ], [ "Maltoni", "F.", "" ], [ "Morisi", "S.", "" ], [ "Muhlleitner", "M. M.", "" ], [ "Mukhopadhyaya", "B.", "" ], [ "Neubert", "M.", "" ], [ "Olive", "K. A.", "" ], [ "Perez", "G.", "" ], [ "Perez", "P. Fileviez", "" ], [ "Plehn", "T.", "" ], [ "Ponton", "E.", "" ], [ "Porod", "W.", "" ], [ "Quevedo", "F.", "" ], [ "Rauch", "M.", "" ], [ "Restrepo", "D.", "" ], [ "Rizzo", "T. G.", "" ], [ "Romao", "J. C.", "" ], [ "Ronga", "F. J.", "" ], [ "Santiago", "J.", "" ], [ "Schechter", "J.", "" ], [ "Senjanovic", "G.", "" ], [ "Shao", "J.", "" ], [ "Spira", "M.", "" ], [ "Stieberger", "S.", "" ], [ "Sullivan", "Z.", "" ], [ "Tait", "T. M. P.", "" ], [ "Tata", "X.", "" ], [ "Taylor", "T. R.", "" ], [ "Toharia", "M.", "" ], [ "Wacker", "J.", "" ], [ "Wagner", "C. E. M.", "" ], [ "Wang", "L. -T.", "" ], [ "Weiglein", "G.", "" ], [ "Zeppenfeld", "D.", "" ], [ "Zurek", "K.", "" ] ]
The Large Hadron Collider presents an unprecedented opportunity to probe the realm of new physics in the TeV region and shed light on some of the core unresolved issues of particle physics. These include the nature of electroweak symmetry breaking, the origin of mass, the possible constituent of cold dark matter, new sources of CP violation needed to explain the baryon excess in the universe, the possible existence of extra gauge groups and extra matter, and importantly the path Nature chooses to resolve the hierarchy problem - is it supersymmetry or extra dimensions. Many models of new physics beyond the standard model contain a hidden sector which can be probed at the LHC. Additionally, the LHC will be a top factory and accurate measurements of the properties of the top and its rare decays will provide a window to new physics. Further, the LHC could shed light on the origin of neutralino masses if the new physics associated with their generation lies in the TeV region. Finally, the LHC is also a laboratory to test the hypothesis of TeV scale strings and D-brane models. An overview of these possibilities is presented in the spirit that it will serve as a companion to the Technical Design Reports (TDRs) by the particle detector groups ATLAS and CMS to facilitate the test of the new theoretical ideas at the LHC. Which of these ideas stands the test of the LHC data will govern the course of particle physics in the subsequent decades.
1512.02576
Oliver Witzel
R.C. Brower, A. Hasenfratz, C. Rebbi, E. Weinberg, O. Witzel
Composite Higgs model at a conformal fixed point
Updated and with added references to match published version. 6 pages, 3 figures
Phys. Rev. D 93, 075028 (2016)
10.1103/PhysRevD.93.075028
EDINBURGH 2015/31
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose to construct a chirally broken model based on the infrared fixed point of a conformal system by raising the mass of some flavors while keeping the others massless. In the infrared limit the massive fermions decouple and the massless fermions break chiral symmetry. The running coupling of this system "walks" and the energy range of walking can be tuned by the mass of the heavy flavors. Renormalization group considerations predict that the spectrum of such a system shows hyperscaling. We have studied a model with four light and eight heavy flavors coupled to SU(3) gauge fields and verified the above expectations. We determined the mass of several hadronic states and found that some of them are in the 2-3 TeV range if the scale is set by the pseudoscalar decay constant $F_\pi \approx 250$ GeV. The $0^{++}$ scalar state behaves very differently from the other hadronic states. In most of our simulations it is nearly degenerate with the pion and we estimate its mass to be less than half of the vector resonance mass.
[ { "created": "Tue, 8 Dec 2015 18:31:06 GMT", "version": "v1" }, { "created": "Thu, 28 Apr 2016 12:55:40 GMT", "version": "v2" } ]
2016-04-29
[ [ "Brower", "R. C.", "" ], [ "Hasenfratz", "A.", "" ], [ "Rebbi", "C.", "" ], [ "Weinberg", "E.", "" ], [ "Witzel", "O.", "" ] ]
We propose to construct a chirally broken model based on the infrared fixed point of a conformal system by raising the mass of some flavors while keeping the others massless. In the infrared limit the massive fermions decouple and the massless fermions break chiral symmetry. The running coupling of this system "walks" and the energy range of walking can be tuned by the mass of the heavy flavors. Renormalization group considerations predict that the spectrum of such a system shows hyperscaling. We have studied a model with four light and eight heavy flavors coupled to SU(3) gauge fields and verified the above expectations. We determined the mass of several hadronic states and found that some of them are in the 2-3 TeV range if the scale is set by the pseudoscalar decay constant $F_\pi \approx 250$ GeV. The $0^{++}$ scalar state behaves very differently from the other hadronic states. In most of our simulations it is nearly degenerate with the pion and we estimate its mass to be less than half of the vector resonance mass.
1912.09740
Shinya Matsuzaki
Hiroyuki Ishida and Shinya Matsuzaki
A Walking Dilaton Inflation
10 pages, 1 figure; references and footnotes added; some discussion added,version published in PLB
null
10.1016/j.physletb.2020.135390
KEK-TH-2181
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose an inflationary scenario based on a many-flavor hidden QCD with eight flavors, which realizes the almost scale-invariant (walking) gauge dynamics. The theory predicts two types of composite (pseudo) Nambu-Goldstone bosons, the pions and the lightest scalar (dilaton) associated with the spontaneous chiral symmetry breaking and its simultaneous violation of the approximate scale invariance. The dilaton acts as an inflaton, where the inflaton potential is induced by the nonperturbative-scale anomaly linked with the underlying theory. The inflaton potential parameters are highly constrained by the walking nature, which are evaluated by straightforward nonperturbative analyses including lattice simulations. Due to the pseudo Nambu-Goldstone boson's natures and the intrinsic property for the chiral symmetry breaking in the walking gauge dynamics, the inflaton coupled to the pions naturally undergoes the small field inflation consistently with all the cosmological and astrophysical constraints presently placed by Planck 2018 data. When the theory is vector-likely coupled to the standard model in part in a way to realize a dynamical electroweak symmetry breaking, the reheating temperature is determined by the pion decays to electroweak gauge bosons. The proposed inflationary scenario would provide a dynamical origin for the small field inflation as well as the light pions as a smoking-gun to be probed by future experiments.
[ { "created": "Fri, 20 Dec 2019 10:22:19 GMT", "version": "v1" }, { "created": "Tue, 7 Jan 2020 03:50:48 GMT", "version": "v2" }, { "created": "Wed, 25 Mar 2020 04:50:26 GMT", "version": "v3" } ]
2020-03-26
[ [ "Ishida", "Hiroyuki", "" ], [ "Matsuzaki", "Shinya", "" ] ]
We propose an inflationary scenario based on a many-flavor hidden QCD with eight flavors, which realizes the almost scale-invariant (walking) gauge dynamics. The theory predicts two types of composite (pseudo) Nambu-Goldstone bosons, the pions and the lightest scalar (dilaton) associated with the spontaneous chiral symmetry breaking and its simultaneous violation of the approximate scale invariance. The dilaton acts as an inflaton, where the inflaton potential is induced by the nonperturbative-scale anomaly linked with the underlying theory. The inflaton potential parameters are highly constrained by the walking nature, which are evaluated by straightforward nonperturbative analyses including lattice simulations. Due to the pseudo Nambu-Goldstone boson's natures and the intrinsic property for the chiral symmetry breaking in the walking gauge dynamics, the inflaton coupled to the pions naturally undergoes the small field inflation consistently with all the cosmological and astrophysical constraints presently placed by Planck 2018 data. When the theory is vector-likely coupled to the standard model in part in a way to realize a dynamical electroweak symmetry breaking, the reheating temperature is determined by the pion decays to electroweak gauge bosons. The proposed inflationary scenario would provide a dynamical origin for the small field inflation as well as the light pions as a smoking-gun to be probed by future experiments.
1803.09846
Shu-Min Zhao
Shu-Min Zhao, Xue-Qian Li
SUSY Confinement
null
Commun. Theor. Phys. 70 (2018) 175-178
10.1088/0253-6102/70/2/175
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In response to the present status that searching for SUSY particles has been unsuccessful, we propose a bold scenario that SUSY particles are confined inside hadrons with a required condition of $P_R=1$ in analog to the color confinement for quarks. The scenario seems to be able to reconcile the beautiful SUSY theory and non-observation at present experiments. On other aspects, some loopholes in the proposal emerge and require to be answered in the future research.
[ { "created": "Tue, 27 Mar 2018 02:03:50 GMT", "version": "v1" }, { "created": "Fri, 15 Jun 2018 02:55:54 GMT", "version": "v2" } ]
2018-07-24
[ [ "Zhao", "Shu-Min", "" ], [ "Li", "Xue-Qian", "" ] ]
In response to the present status that searching for SUSY particles has been unsuccessful, we propose a bold scenario that SUSY particles are confined inside hadrons with a required condition of $P_R=1$ in analog to the color confinement for quarks. The scenario seems to be able to reconcile the beautiful SUSY theory and non-observation at present experiments. On other aspects, some loopholes in the proposal emerge and require to be answered in the future research.
1011.2703
Eugene Zabrodin
J. Bleibel, L.V. Bravina, E.E. Zabrodin
How many of the scaling trends in $pp$ collisions will be violated at sqrt{s_NN} = 14 TeV ? - Predictions from Monte Carlo quark-gluon string model
null
Phys. Rev. D 93, 114012 (2016)
10.1103/PhysRevD.93.114012
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multiplicity, rapidity and transverse momentum distributions of hadrons produced both in inelastic and nondiffractive $pp$ collisions at energies from $\sqrt{s} = 200$\,GeV to 14\,TeV are studied within the Monte Carlo quark-gluon string model (QGSM). Good agreement with the available experimental data up to $\sqrt{s} = 13$\,TeV is obtained, and predictions are made for the collisions at top LHC energy $\sqrt{s} = 14$\,TeV. The model indicates that Feynman scaling and extended longitudinal scaling remain valid in the fragmentation regions, whereas strong violation of Feynman scaling is observed at midrapidity. The Koba-Nielsen-Olesen (KNO) scaling in multiplicity distributions is violated at LHC also. The origin of both maintenance and violation of the scaling trends is traced to short range correlations of particles in the strings and interplay between the multistring processes at ultrarelativistic energies.
[ { "created": "Thu, 11 Nov 2010 16:44:21 GMT", "version": "v1" }, { "created": "Fri, 10 Jun 2016 15:56:43 GMT", "version": "v2" } ]
2016-06-15
[ [ "Bleibel", "J.", "" ], [ "Bravina", "L. V.", "" ], [ "Zabrodin", "E. E.", "" ] ]
Multiplicity, rapidity and transverse momentum distributions of hadrons produced both in inelastic and nondiffractive $pp$ collisions at energies from $\sqrt{s} = 200$\,GeV to 14\,TeV are studied within the Monte Carlo quark-gluon string model (QGSM). Good agreement with the available experimental data up to $\sqrt{s} = 13$\,TeV is obtained, and predictions are made for the collisions at top LHC energy $\sqrt{s} = 14$\,TeV. The model indicates that Feynman scaling and extended longitudinal scaling remain valid in the fragmentation regions, whereas strong violation of Feynman scaling is observed at midrapidity. The Koba-Nielsen-Olesen (KNO) scaling in multiplicity distributions is violated at LHC also. The origin of both maintenance and violation of the scaling trends is traced to short range correlations of particles in the strings and interplay between the multistring processes at ultrarelativistic energies.
hep-ph/0209011
Masashi Wakamatsu
M. Wakamatsu
Light-flavor sea-quark distributions in the nucleon in the SU(3) chiral quark soliton model (I) -- phenomenological predictions --
36 pages, 20 EPS figures. The revised version accepted for publication in Phys. Rev. D. The title has been changed, and the body of the paper has been divided into two pieces, i.e.. the present one which discusses the main phenomenological predictions of the model and the other one which describes the detailed formulation of the flavor SU(3) chiral quark soliton model to predict light-flavor quark and antiquark distribution functions in the nucleon
null
10.1103/PhysRevD.67.034005
OU-HEP-416
hep-ph nucl-th
null
Theoretical predictions are given for the light-flavor sea-quark distributions including the strange quark ones on the basis of the flavor SU(3) version of the chiral quark soliton model. Careful account is taken here of the SU(3) symmetry breaking effects due to the mass difference between the strange and nonstrange quarks. This effective mass difference $\Delta m_s$ between the strange and nonstrange quarks is the only one parameter necessary for the flavor SU(3) generalization of the model. A particular emphasis of study is put on the {\it light-flavor sea-quark asymmetry} as exemplified by the observables $\bar{d} (x) - \bar{u} (x), \bar{d} (x) / \bar{u} (x), \Delta \bar{u} (x) - \Delta \bar{d} (x)$ as well as on the {\it particle-antiparticle asymmetry} of the strange quark distributions represented by $s (x) - \bar{s} (x), s (x) / \bar{s} (x), \Delta s (x) - \Delta \bar{s} (x)$ etc. As for the unpolarized sea-quark distributions, the predictions of the model seem qualitatively consistent with the available phenomenological information provided by the NMC data for $\bar{d} (x) - \bar{u} (x)$, the E866 data for $\bar{d} (x) / \bar{u} (x)$, the CCFR data and Barone et al.'s fit for $s (x) / \bar{s} (x)$ etc. The model is shown to give several unique predictions also for the spin-dependent sea-quark distribution, such that $\Delta s (x) \ll \Delta \bar{s}(x) \lesssim 0$ and $\Delta \bar{d}(x) < 0 < \Delta \bar{u}(x)$, although the verification of these predictions must await more elaborate experimental investigations in the near future.
[ { "created": "Mon, 2 Sep 2002 03:39:13 GMT", "version": "v1" }, { "created": "Tue, 24 Dec 2002 05:29:43 GMT", "version": "v2" } ]
2009-11-07
[ [ "Wakamatsu", "M.", "" ] ]
Theoretical predictions are given for the light-flavor sea-quark distributions including the strange quark ones on the basis of the flavor SU(3) version of the chiral quark soliton model. Careful account is taken here of the SU(3) symmetry breaking effects due to the mass difference between the strange and nonstrange quarks. This effective mass difference $\Delta m_s$ between the strange and nonstrange quarks is the only one parameter necessary for the flavor SU(3) generalization of the model. A particular emphasis of study is put on the {\it light-flavor sea-quark asymmetry} as exemplified by the observables $\bar{d} (x) - \bar{u} (x), \bar{d} (x) / \bar{u} (x), \Delta \bar{u} (x) - \Delta \bar{d} (x)$ as well as on the {\it particle-antiparticle asymmetry} of the strange quark distributions represented by $s (x) - \bar{s} (x), s (x) / \bar{s} (x), \Delta s (x) - \Delta \bar{s} (x)$ etc. As for the unpolarized sea-quark distributions, the predictions of the model seem qualitatively consistent with the available phenomenological information provided by the NMC data for $\bar{d} (x) - \bar{u} (x)$, the E866 data for $\bar{d} (x) / \bar{u} (x)$, the CCFR data and Barone et al.'s fit for $s (x) / \bar{s} (x)$ etc. The model is shown to give several unique predictions also for the spin-dependent sea-quark distribution, such that $\Delta s (x) \ll \Delta \bar{s}(x) \lesssim 0$ and $\Delta \bar{d}(x) < 0 < \Delta \bar{u}(x)$, although the verification of these predictions must await more elaborate experimental investigations in the near future.
hep-ph/9504336
Jeff Forshaw
J.R. Forshaw R.G. Roberts R.S. Thorne (Rutherford Appleton Lab)
Analytic Approach to Small-X Structure Functions
15 pages Latex + 5 figures which are compressed as a uuencoded file (Physics Letters B -- to appear)
Phys.Lett.B356:79-88,1995
10.1016/0370-2693(95)00812-Y
RAL-95-035
hep-ph
null
We present a method for the analytic solution of small $x$ structure functions. The essential small $x$ logarithms are summed to all orders in the anomalous dimensions and coefficient functions. Although we work at leading logarithmic accuracy, the method is general enough to allow the systematic inclusion of sub-leading logarithms. Results and predictions are presented for the gluon density, and the structure functions $F_2(x,Q^2)$ and $F_L(x,Q^2)$. We find that corrections to the simple double logarithmic calculation are important in the HERA range and obtain good fits to all available data.
[ { "created": "Wed, 19 Apr 1995 13:19:07 GMT", "version": "v1" }, { "created": "Mon, 3 Jul 1995 17:41:54 GMT", "version": "v2" } ]
2010-03-25
[ [ "Thorne", "J. R. Forshaw R. G. Roberts R. S.", "", "Rutherford Appleton Lab" ] ]
We present a method for the analytic solution of small $x$ structure functions. The essential small $x$ logarithms are summed to all orders in the anomalous dimensions and coefficient functions. Although we work at leading logarithmic accuracy, the method is general enough to allow the systematic inclusion of sub-leading logarithms. Results and predictions are presented for the gluon density, and the structure functions $F_2(x,Q^2)$ and $F_L(x,Q^2)$. We find that corrections to the simple double logarithmic calculation are important in the HERA range and obtain good fits to all available data.
2007.13736
Alexander Kartavtsev
A. Kartavtsev
Accounting for the Heisenberg and Pauli principles in the kinetic approach to neutrino oscillations
35 pages, 4 figures, minor refinements in the main text, two appendices added
JHEP11(2020)135
10.1007/JHEP11(2020)135
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
While oscillations of solar neutrinos are usually studied using the single-particle quantum-mechanical approach, flavor conversions of supernovae neutrinos are typically analyzed using the kinetic equation for the matrix of densities due to the necessity of including also the scattering processes. Using the Wigner formulation of quantum mechanics we show the equivalence of the quantum-mechanical and kinetic approaches in the limit of collisionless neutrino propagation (in a background medium). Based on this observation we also argue that solutions of the kinetic equation account for the Heisenberg uncertainty principle and the related effect of wave packet separation (for single neutrinos), as well as the Pauli exclusion principle, if the initial conditions are consistent with these fundamental quantum principles. Such initial conditions can be constructed e.g. by identifying the matrix of densities with the (reduced) single-particle Wigner function computed using initial conditions for the neutrino wave function. Hence the neutrino momentum uncertainty is an integral part of the initial conditions for the matrix of densities, that may have an impact on the phenomenology of supernovae neutrinos via the effect of wave packet separation.
[ { "created": "Sun, 26 Jul 2020 13:22:00 GMT", "version": "v1" }, { "created": "Wed, 25 Nov 2020 14:40:23 GMT", "version": "v2" } ]
2020-11-26
[ [ "Kartavtsev", "A.", "" ] ]
While oscillations of solar neutrinos are usually studied using the single-particle quantum-mechanical approach, flavor conversions of supernovae neutrinos are typically analyzed using the kinetic equation for the matrix of densities due to the necessity of including also the scattering processes. Using the Wigner formulation of quantum mechanics we show the equivalence of the quantum-mechanical and kinetic approaches in the limit of collisionless neutrino propagation (in a background medium). Based on this observation we also argue that solutions of the kinetic equation account for the Heisenberg uncertainty principle and the related effect of wave packet separation (for single neutrinos), as well as the Pauli exclusion principle, if the initial conditions are consistent with these fundamental quantum principles. Such initial conditions can be constructed e.g. by identifying the matrix of densities with the (reduced) single-particle Wigner function computed using initial conditions for the neutrino wave function. Hence the neutrino momentum uncertainty is an integral part of the initial conditions for the matrix of densities, that may have an impact on the phenomenology of supernovae neutrinos via the effect of wave packet separation.
hep-ph/9604244
J. W. F. Valle
J. C. Romao (IST, Lisbon), F. de Campos (IFT, Unesp, Brazil), M. A. Garcia-Jareno, M. B. Magro and J. W. F. Valle (IFIC, U. Valencia)
LEP Sensitivities to Spontaneous R-Parity Violating Signals
28 pages, LaTex file + 6 figures, all compressed by uufiles, also available from anonymous ftp at ftp://neutrinos.uv.es/pub/papers/ps/rpv_lep1.uu
Nucl.Phys.B482:3-23,1996
10.1016/S0550-3213(96)00494-4
FTUV/96-06; IFIC/96-07
hep-ph
null
We illustrate the sensitivities of LEP experiments to leptonic signals associated to models where supersymmetry (SUSY) is realized with spontaneous breaking of R-parity. We focus on missing transverse momentum plus acoplanar muon events arising from lightest neutralino single production $\chi \nu$ as well as pair production $\chi \chi$, followed by $\chi$ decays, where $\chi$ denotes the lightest neutralino. We show that the integrated luminosity achieved at LEP already starts probing the basic parameters of the theory. We discuss the significance of these constraints for the simplest spontaneous R-parity breaking models and their relevance for future searches of SUSY particles.
[ { "created": "Thu, 4 Apr 1996 10:12:48 GMT", "version": "v1" } ]
2009-09-17
[ [ "Romao", "J. C.", "", "IST, Lisbon" ], [ "de Campos", "F.", "", "IFT, Unesp, Brazil" ], [ "Garcia-Jareno", "M. A.", "", "IFIC, U. Valencia" ], [ "Magro", "M. B.", "", "IFIC, U. Valencia" ], [ "Valle", "J. W. F.", "", "IFIC, U. Valencia" ] ]
We illustrate the sensitivities of LEP experiments to leptonic signals associated to models where supersymmetry (SUSY) is realized with spontaneous breaking of R-parity. We focus on missing transverse momentum plus acoplanar muon events arising from lightest neutralino single production $\chi \nu$ as well as pair production $\chi \chi$, followed by $\chi$ decays, where $\chi$ denotes the lightest neutralino. We show that the integrated luminosity achieved at LEP already starts probing the basic parameters of the theory. We discuss the significance of these constraints for the simplest spontaneous R-parity breaking models and their relevance for future searches of SUSY particles.
1610.05144
Edward Shuryak
Edward Shuryak and Ismail Zahed
CP violation during the electroweak sphaleron transitions
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We suggest a specific semiclassical background field, the so called pure gauge sphaleron explosion, to evaluate the magnitude of the CP violation stemming from the standard phase of the CKM matrix. We use it to evaluate the matrix elements of some next-to-leading order effective CP-violating operators suggested in the literature. We also derive the scale dependence of the corresponding coefficients. Finally, we discuss the expected magnitude of the CP violation in the cold electroweak scenario.
[ { "created": "Mon, 17 Oct 2016 14:41:53 GMT", "version": "v1" } ]
2016-10-18
[ [ "Shuryak", "Edward", "" ], [ "Zahed", "Ismail", "" ] ]
We suggest a specific semiclassical background field, the so called pure gauge sphaleron explosion, to evaluate the magnitude of the CP violation stemming from the standard phase of the CKM matrix. We use it to evaluate the matrix elements of some next-to-leading order effective CP-violating operators suggested in the literature. We also derive the scale dependence of the corresponding coefficients. Finally, we discuss the expected magnitude of the CP violation in the cold electroweak scenario.
hep-ph/0009092
Hiroshi Nunokawa
Hiroshi Nunokawa
Status of the solutions to neutrino anomalies based on non-standard neutrino interactions
6 pages with 8 postscript figures, uses espcrc2.sty, Talk presented at ``NuFact'00'' workshop, Monterey, CA, USA, May 22-26, 2000
Nucl.Instrum.Meth. A472 (2000) 443-450
10.1016/S0168-9002(01)01289-X
null
hep-ph
null
We review the status of the solutions to neutrino anomalies by flavor-changing as well as flavor-diagonal neutrino interactions. While it is difficult to explain the atmospheric neutrino data the solar neutrino data can be well accounted for by the massless neutrino oscillation induced by such non-standard neutrino interactions. We also discuss the possibility to test such kind of interactions by the future neutrino oscillation experiments at neutrino factories.
[ { "created": "Thu, 7 Sep 2000 22:00:23 GMT", "version": "v1" } ]
2009-10-31
[ [ "Nunokawa", "Hiroshi", "" ] ]
We review the status of the solutions to neutrino anomalies by flavor-changing as well as flavor-diagonal neutrino interactions. While it is difficult to explain the atmospheric neutrino data the solar neutrino data can be well accounted for by the massless neutrino oscillation induced by such non-standard neutrino interactions. We also discuss the possibility to test such kind of interactions by the future neutrino oscillation experiments at neutrino factories.
hep-ph/0503192
Paulo Rodrigues da Silva
Alex G. Dias, C. A. de S. Pires, V. Pleitez, P. S. Rodrigues da Silva
Dynamically Induced Spontaneous Symmetry Breaking in 3-3-1 Models
12 pages, typos corrected, improved text, conclusions unchanged
Phys.Lett. B621 (2005) 151-159
10.1016/j.physletb.2005.06.048
IFT-P.010/2005
hep-ph
null
We show that in SU(3)_C X SU(3)_L X U(1)_N (3-3-1) models embedded with a singlet scalar playing the role of the axion, after imposing scale invariance, dynamical symmetry breaking of Peccei-Quinn symmetry occurs through the one-loop effective potential for the singlet field. We, then, analyze the structure of spontaneous symmetry breaking by studying the new scalar potential for the model, and verify that electroweak symmetry breaking is tightly connected to the 3-3-1 breaking by the strong constraints among their vacuum expectation values. This offers a valuable guide to write down the correct pattern of symmetry breaking for multi-scalar theories. We also obtained that the accompanying massive pseudo-scalar, instead of acquiring mass of order of Peccei-Quinn scale as we would expect, develops a mass at a much lower scale, a consequence solely of the dynamical breaking.
[ { "created": "Fri, 18 Mar 2005 20:05:44 GMT", "version": "v1" }, { "created": "Fri, 13 May 2005 17:48:01 GMT", "version": "v2" } ]
2009-11-11
[ [ "Dias", "Alex G.", "" ], [ "Pires", "C. A. de S.", "" ], [ "Pleitez", "V.", "" ], [ "da Silva", "P. S. Rodrigues", "" ] ]
We show that in SU(3)_C X SU(3)_L X U(1)_N (3-3-1) models embedded with a singlet scalar playing the role of the axion, after imposing scale invariance, dynamical symmetry breaking of Peccei-Quinn symmetry occurs through the one-loop effective potential for the singlet field. We, then, analyze the structure of spontaneous symmetry breaking by studying the new scalar potential for the model, and verify that electroweak symmetry breaking is tightly connected to the 3-3-1 breaking by the strong constraints among their vacuum expectation values. This offers a valuable guide to write down the correct pattern of symmetry breaking for multi-scalar theories. We also obtained that the accompanying massive pseudo-scalar, instead of acquiring mass of order of Peccei-Quinn scale as we would expect, develops a mass at a much lower scale, a consequence solely of the dynamical breaking.
hep-ph/0006067
William H. Kinney
Martina Brisudova and William H. Kinney (Univ. of Florida)
Back reaction of a long range force on a Friedmann-Robertson-Walker background
14 pages, 6 color Postscript figures, LaTeX
Phys.Rev. D62 (2000) 103516
10.1103/PhysRevD.62.103516
null
hep-ph astro-ph
null
It is possible that there may exist long-range forces in addition to gravity. In this paper we construct a simple model for such a force based on exchange of a massless scalar field and analyze its effect on the evolution of a homogeneous Friedmann-Robertson-Walker cosmology. The presence of such an interaction leads to an equation of state characterized by positive pressure and to resonant particle production similar to that observed in preheating scenarios.
[ { "created": "Wed, 7 Jun 2000 20:01:44 GMT", "version": "v1" } ]
2009-10-31
[ [ "Brisudova", "Martina", "", "Univ. of Florida" ], [ "Kinney", "William H.", "", "Univ. of Florida" ] ]
It is possible that there may exist long-range forces in addition to gravity. In this paper we construct a simple model for such a force based on exchange of a massless scalar field and analyze its effect on the evolution of a homogeneous Friedmann-Robertson-Walker cosmology. The presence of such an interaction leads to an equation of state characterized by positive pressure and to resonant particle production similar to that observed in preheating scenarios.
0804.4711
Thomas D. Cohen
Thomas D. Cohen, Juan A. Ponciano and Norberto N. Scoccola
On Skyrmion semiclassical quantization in the presence of an isospin chemical potential
12 pages, 4 figures
Phys.Rev.D78:034040,2008
10.1103/PhysRevD.78.034040
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The semiclassical description of Skyrmions at small isospin chemical potential $\mu_I$ is carefully analyzed. We show that when the calculation of the energy of a nucleon is performed using the straightforward generalization of the vacuum sector techniques ($\mu_I=0$), together with the "natural" assumption $\mu_I = {\cal O} (N_c^0)$, the proton and neutron masses are nonlinear in $\mu_I$ in the regime $|\mu_I| < m_\pi$. Although these nonlinearities turn out to be numerically quite small, such a result fails to strictly agree with the very robust prediction that for those values of $\mui$ the energy excitations above the vacuum are linear in $\mu_I$. The resolution of this paradox is achieved by studying the realization of the large $N_c$ limit of $QCD$ in the Skyrme model at finite $\mui$. This is done in a simplified context devoid of the technical complications present in the Skyrme model but which fully displays the general scaling behavior with $N_c$. The analysis shows that the paradoxical result appears as a symptom of using the semi-classical approach beyond its regime of validity and that, at a formal level, the standard methods for dealing with the Skyrme model are only strictly justified for states of high isospin $I \sim N_c$.
[ { "created": "Wed, 30 Apr 2008 00:27:20 GMT", "version": "v1" } ]
2008-11-26
[ [ "Cohen", "Thomas D.", "" ], [ "Ponciano", "Juan A.", "" ], [ "Scoccola", "Norberto N.", "" ] ]
The semiclassical description of Skyrmions at small isospin chemical potential $\mu_I$ is carefully analyzed. We show that when the calculation of the energy of a nucleon is performed using the straightforward generalization of the vacuum sector techniques ($\mu_I=0$), together with the "natural" assumption $\mu_I = {\cal O} (N_c^0)$, the proton and neutron masses are nonlinear in $\mu_I$ in the regime $|\mu_I| < m_\pi$. Although these nonlinearities turn out to be numerically quite small, such a result fails to strictly agree with the very robust prediction that for those values of $\mui$ the energy excitations above the vacuum are linear in $\mu_I$. The resolution of this paradox is achieved by studying the realization of the large $N_c$ limit of $QCD$ in the Skyrme model at finite $\mui$. This is done in a simplified context devoid of the technical complications present in the Skyrme model but which fully displays the general scaling behavior with $N_c$. The analysis shows that the paradoxical result appears as a symptom of using the semi-classical approach beyond its regime of validity and that, at a formal level, the standard methods for dealing with the Skyrme model are only strictly justified for states of high isospin $I \sim N_c$.
2210.09780
Boris Altshuler
Boris Altshuler
Quark mixing angles vs quark masses: potential approach
13 pages
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
It is shown that phenomenologically favorable expressions of quark mixing angles through the ratios of current quark masses may be derived as stable points of certain 4-th power in CKM matrix flavor-invariant potentials built with traces of 3x3 quark up and down mass matrices.
[ { "created": "Tue, 18 Oct 2022 11:47:19 GMT", "version": "v1" }, { "created": "Tue, 25 Oct 2022 08:51:37 GMT", "version": "v2" }, { "created": "Mon, 12 Dec 2022 17:10:04 GMT", "version": "v3" } ]
2022-12-13
[ [ "Altshuler", "Boris", "" ] ]
It is shown that phenomenologically favorable expressions of quark mixing angles through the ratios of current quark masses may be derived as stable points of certain 4-th power in CKM matrix flavor-invariant potentials built with traces of 3x3 quark up and down mass matrices.
hep-ph/9801206
Han Meng
Jiang Yi, Zhou Mian-Lai, Ma Wen-Gan, Han Liang, Zhou Hong and Han Meng (USTC P.R.China)
Probing flavor changing interactions in photon-photon collisions
22 pages, LaTeX, including 5 figures in eps files
Phys.Rev.D57:4343-4351,1998
10.1103/PhysRevD.57.4343
null
hep-ph
null
We examine the subprocess $\gamma\gamma \to t\bar{c}+\bar{t}c$ at electron-positron colliders in the two-Higgs-doublet model with flavor-changing scalar couplings, where all the one-loop contribuions are considered, and the results are applicable to the whole mass range of the weakly coupled Higgs bosons. Because of the heavy top quark mass, this process is important in probing the flavor-changing top-charm-scalar vertex and could be detectable at the Next Linear Collider, if the values of the parameters are favorable. The results show that this process is more promising than the direct $e^{+} e^{-}$ process for discovering flavor changing scalar interactions.
[ { "created": "Fri, 2 Jan 1998 02:20:57 GMT", "version": "v1" } ]
2011-07-19
[ [ "Yi", "Jiang", "", "USTC P.R.China" ], [ "Mian-Lai", "Zhou", "", "USTC P.R.China" ], [ "Wen-Gan", "Ma", "", "USTC P.R.China" ], [ "Liang", "Han", "", "USTC P.R.China" ], [ "Hong", "Zhou", "", "USTC P.R.China" ], [ "Meng", "Han", "", "USTC P.R.China" ] ]
We examine the subprocess $\gamma\gamma \to t\bar{c}+\bar{t}c$ at electron-positron colliders in the two-Higgs-doublet model with flavor-changing scalar couplings, where all the one-loop contribuions are considered, and the results are applicable to the whole mass range of the weakly coupled Higgs bosons. Because of the heavy top quark mass, this process is important in probing the flavor-changing top-charm-scalar vertex and could be detectable at the Next Linear Collider, if the values of the parameters are favorable. The results show that this process is more promising than the direct $e^{+} e^{-}$ process for discovering flavor changing scalar interactions.
hep-ph/9308249
Arthur Weldon
H. Arthur Weldon
Cancellation of Infrared Divergences in Thermal QED
6 pages, (Talk presented at Quark Matter '93)
Nucl.Phys. A566 (1994) 581c-584c
10.1016/0375-9474(94)90698-X
null
hep-ph
null
As a preliminary step, the radiation produced by a classical charged current coupled to a quantized $A_{\mu}$ is solved. To each order in $\alpha$, all infrared divergences cancel between the virtual $\gamma$'s and the real $\gamma$'s absorbed from the plasma or emitted into the plasma. When all orders of perturbation theory are summed, the finite answer predicts a suppression of radiation with $\omega< \alpha T$. The analysis of QED then consists of two steps. First, a general probability at $T\neq 0$ is organized so that all the virtual $e^{\pm},\gamma$ are in the amplitudes and all the real $e^{\pm},\gamma$ are in the phase space integrations. Next, the cancellations of IR divergences between virtual and real are demonstrated.
[ { "created": "Mon, 9 Aug 1993 20:45:39 GMT", "version": "v1" } ]
2009-10-22
[ [ "Weldon", "H. Arthur", "" ] ]
As a preliminary step, the radiation produced by a classical charged current coupled to a quantized $A_{\mu}$ is solved. To each order in $\alpha$, all infrared divergences cancel between the virtual $\gamma$'s and the real $\gamma$'s absorbed from the plasma or emitted into the plasma. When all orders of perturbation theory are summed, the finite answer predicts a suppression of radiation with $\omega< \alpha T$. The analysis of QED then consists of two steps. First, a general probability at $T\neq 0$ is organized so that all the virtual $e^{\pm},\gamma$ are in the amplitudes and all the real $e^{\pm},\gamma$ are in the phase space integrations. Next, the cancellations of IR divergences between virtual and real are demonstrated.
hep-ph/9607422
Konstantin Chetyrkin
K.G. Chetyrkin, J.H. K\"uhn, M. Steinhauser
Higher Moments of Heavy Quark Vacuum Polarization
9 pages, LaTeX, no figures, sprocl.sty provided (To appear in the Proceedings of the Second Workshop on Continuous Advances in QCD, Minneapolis, U.S.A., March 1996). Postscript also available at ftp://www-ttp.physik.uni-karlsruhe.de/ttp96-22/ttp96-22.ps or at http://www-ttp.physik.uni-karlsruhe.de/cgi-bin/preprints/
null
10.1016/S0920-5632(96)90008-0
TTP96-22, MPI/PhT/96-66
hep-ph
null
We present analytical calculation of the first seven moments of the heavy quark vacuum polarization function in the three-loop order. The obtained results are compared against the asymptotic formulas following from the threshold singularities. We also discuss the $\mu$ dependence of the moments within the BLM procedure.
[ { "created": "Thu, 25 Jul 1996 07:44:22 GMT", "version": "v1" } ]
2015-06-25
[ [ "Chetyrkin", "K. G.", "" ], [ "Kühn", "J. H.", "" ], [ "Steinhauser", "M.", "" ] ]
We present analytical calculation of the first seven moments of the heavy quark vacuum polarization function in the three-loop order. The obtained results are compared against the asymptotic formulas following from the threshold singularities. We also discuss the $\mu$ dependence of the moments within the BLM procedure.
hep-ph/9906256
Sorin Codoban
S. Codoban, D.I. Kazakov
Approximate Analytic Solutions of RG Equations for Yukawa and Soft Couplings in SUSY Models
14 pages, LaTex, 4 eps figures, some comments added, final version
Eur.Phys.J.C13:671-679,2000
10.1007/s100520050726
null
hep-ph
null
We present simple analytical formulae which describe solutions of the RG equations for Yukawa couplings in SUSY gauge theories with the accuracy of a few per cent. Performing the Grassmannian expansion in these solutions one finds those for all the soft couplings and masses. The solutions clearly exhibit the fixed point behaviour which can be calculated analytically. A comparison with numerical solutions is demonstrated.
[ { "created": "Fri, 4 Jun 1999 13:41:50 GMT", "version": "v1" }, { "created": "Wed, 9 Jun 1999 13:01:14 GMT", "version": "v2" }, { "created": "Wed, 31 May 2000 11:18:49 GMT", "version": "v3" } ]
2011-09-13
[ [ "Codoban", "S.", "" ], [ "Kazakov", "D. I.", "" ] ]
We present simple analytical formulae which describe solutions of the RG equations for Yukawa couplings in SUSY gauge theories with the accuracy of a few per cent. Performing the Grassmannian expansion in these solutions one finds those for all the soft couplings and masses. The solutions clearly exhibit the fixed point behaviour which can be calculated analytically. A comparison with numerical solutions is demonstrated.
1103.4387
Hisakazu Minakata
Katsuhiro Asano, Hisakazu Minakata
Large-Theta(13) Perturbation Theory of Neutrino Oscillation for Long-Baseline Experiments
Fig.2 added, 23 pages. Matches to the published version
JHEP 1106:022,2011
10.1007/JHEP06(2011)022
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Cervera et al. formula, the best known approximate formula of neutrino oscillation probability for long-baseline experiments, can be regarded as a second-order perturbative formula with small expansion parameter epsilon \equiv Delta m^2_{21} / Delta m^2_{31} \simeq 0.03 under the assumption s_{13} \simeq epsilon. If theta_{13} is large, as suggested by a candidate nu_{e} event at T2K as well as the recent global analyses, higher order corrections of s_{13} to the formula would be needed for better accuracy. We compute the corrections systematically by formulating a perturbative framework by taking theta_{13} as s_{13} \sim \sqrt{epsilon} \simeq 0.18, which guarantees its validity in a wide range of theta_{13} below the Chooz limit. We show on general ground that the correction terms must be of order epsilon^2. Yet, they nicely fill the mismatch between the approximate and the exact formulas at low energies and relatively long baselines. General theorems are derived which serve for better understanding of delta-dependence of the oscillation probability. Some interesting implications of the large theta_{13} hypothesis are discussed.
[ { "created": "Tue, 22 Mar 2011 21:28:03 GMT", "version": "v1" }, { "created": "Thu, 7 Apr 2011 09:43:11 GMT", "version": "v2" }, { "created": "Mon, 13 Jun 2011 23:04:20 GMT", "version": "v3" } ]
2015-03-19
[ [ "Asano", "Katsuhiro", "" ], [ "Minakata", "Hisakazu", "" ] ]
The Cervera et al. formula, the best known approximate formula of neutrino oscillation probability for long-baseline experiments, can be regarded as a second-order perturbative formula with small expansion parameter epsilon \equiv Delta m^2_{21} / Delta m^2_{31} \simeq 0.03 under the assumption s_{13} \simeq epsilon. If theta_{13} is large, as suggested by a candidate nu_{e} event at T2K as well as the recent global analyses, higher order corrections of s_{13} to the formula would be needed for better accuracy. We compute the corrections systematically by formulating a perturbative framework by taking theta_{13} as s_{13} \sim \sqrt{epsilon} \simeq 0.18, which guarantees its validity in a wide range of theta_{13} below the Chooz limit. We show on general ground that the correction terms must be of order epsilon^2. Yet, they nicely fill the mismatch between the approximate and the exact formulas at low energies and relatively long baselines. General theorems are derived which serve for better understanding of delta-dependence of the oscillation probability. Some interesting implications of the large theta_{13} hypothesis are discussed.
hep-ph/9406205
J. Wudka
Jose Wudka
Electroweak effective lagrangians
89 pages
Int.J.Mod.Phys. A9 (1994) 2301-2362
10.1142/S0217751X94000959
UCRHEP-T121
hep-ph
null
In this paper I review several aspects of the use of effective lagrangians in (mainly) electroweak physics. The conditions under which this approach is reliable and useful, as well as the limitations of the formalism are detailed. Various applications are also presented.
[ { "created": "Wed, 1 Jun 1994 17:52:21 GMT", "version": "v1" } ]
2015-06-25
[ [ "Wudka", "Jose", "" ] ]
In this paper I review several aspects of the use of effective lagrangians in (mainly) electroweak physics. The conditions under which this approach is reliable and useful, as well as the limitations of the formalism are detailed. Various applications are also presented.
2105.04530
Bin Yan
Bin Yan
Determining Higgs boson width at electron-positron colliders
8 pages, 7 figures, the published version in PLB
null
10.1016/j.physletb.2021.136709
LA-UR-21-24315
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Probing Higgs width $\Gamma_h$ is critical to test the Higgs properties. In this work we propose to measure $\Gamma_h$ at the $e^+e^-$ collider with a model-independent analysis under the Standard Model Effective Field Theory framework. We demonstrate that making use of the cross section measurements from $e^+e^-\to Zh$, $e^+e^-\to \nu_e\bar{\nu}_eh$ production and Higgs decay branching ratios $h\to WW^*/ZZ^*/\gamma\gamma$, one could determine $\Gamma_h$ at a percentage level with a center of mass energy $\sqrt{s}=250$ and 350 GeV and integrated luminosity $5~{\rm ab}^{-1}$. This conclusion would not depend on the assumption of the fermion Yukawa interactions. We further apply this result to constrain the fermion Yukawa couplings and it shows that the couplings could be well constrained.
[ { "created": "Mon, 10 May 2021 17:33:04 GMT", "version": "v1" }, { "created": "Tue, 12 Oct 2021 15:58:30 GMT", "version": "v2" } ]
2021-10-13
[ [ "Yan", "Bin", "" ] ]
Probing Higgs width $\Gamma_h$ is critical to test the Higgs properties. In this work we propose to measure $\Gamma_h$ at the $e^+e^-$ collider with a model-independent analysis under the Standard Model Effective Field Theory framework. We demonstrate that making use of the cross section measurements from $e^+e^-\to Zh$, $e^+e^-\to \nu_e\bar{\nu}_eh$ production and Higgs decay branching ratios $h\to WW^*/ZZ^*/\gamma\gamma$, one could determine $\Gamma_h$ at a percentage level with a center of mass energy $\sqrt{s}=250$ and 350 GeV and integrated luminosity $5~{\rm ab}^{-1}$. This conclusion would not depend on the assumption of the fermion Yukawa interactions. We further apply this result to constrain the fermion Yukawa couplings and it shows that the couplings could be well constrained.
hep-ph/9512369
Bernd Krause
Andrzej Czarnecki, Bernd Krause, and William J. Marciano
Electroweak corrections to the muon anomalous magnetic moment
Revtex, 10 pages. Corrected version, submitted to Phys. Rev. Lett. Two-loop electroweak corrections to anomalous magnetic moments of electron and tau are included
Phys.Rev.Lett.76:3267-3270,1996
10.1103/PhysRevLett.76.3267
TTP95-34
hep-ph
null
The bosonic two-loop electroweak radiative corrections to the muon's anomalous magnetic moment, $a_\mu\equiv (g_\mu-2)/2$, are presented. We find $\Delta a_\mu^{\rm EW}({\rm 2\,loop\, bosonic})/ a_\mu^{\rm EW}({\rm 1\,loop})\approx {\alpha\over \pi}\left(-3.6 \ln\left({M_W^2\over m_\mu^2}\right) +0.10 \right)\approx -0.11$ for $M_{\rm Higgs}\approx 250$ GeV. Combining that result with our previous two-loop fermionic calculation, we obtain an overall 22.6\% reduction in $a_\mu^{\rm EW}$ from $195\times 10^{-11}$ to $151(4)\times 10^{-11}$. Implications for the full standard model prediction and an upcoming high precision measurement of $a_\mu$ are briefly discussed. We also give the two-loop electroweak corrections to the anomalous magnetic moments of electron and tau lepton; they result in a reduction of the one-loop estimates by 35\% and 15\%, respectively.
[ { "created": "Wed, 20 Dec 1995 00:16:31 GMT", "version": "v1" }, { "created": "Fri, 22 Dec 1995 15:34:54 GMT", "version": "v2" }, { "created": "Wed, 13 Mar 1996 17:43:31 GMT", "version": "v3" } ]
2014-11-17
[ [ "Czarnecki", "Andrzej", "" ], [ "Krause", "Bernd", "" ], [ "Marciano", "William J.", "" ] ]
The bosonic two-loop electroweak radiative corrections to the muon's anomalous magnetic moment, $a_\mu\equiv (g_\mu-2)/2$, are presented. We find $\Delta a_\mu^{\rm EW}({\rm 2\,loop\, bosonic})/ a_\mu^{\rm EW}({\rm 1\,loop})\approx {\alpha\over \pi}\left(-3.6 \ln\left({M_W^2\over m_\mu^2}\right) +0.10 \right)\approx -0.11$ for $M_{\rm Higgs}\approx 250$ GeV. Combining that result with our previous two-loop fermionic calculation, we obtain an overall 22.6\% reduction in $a_\mu^{\rm EW}$ from $195\times 10^{-11}$ to $151(4)\times 10^{-11}$. Implications for the full standard model prediction and an upcoming high precision measurement of $a_\mu$ are briefly discussed. We also give the two-loop electroweak corrections to the anomalous magnetic moments of electron and tau lepton; they result in a reduction of the one-loop estimates by 35\% and 15\%, respectively.
2310.16036
Artem Roenko
Victor V. Braguta, Maxim N. Chernodub, Ilya E. Kudrov, Artem A. Roenko, Dmitrii A. Sychev
Negative Barnett effect, negative moment of inertia of gluon plasma and thermal evaporation of chromomagnetic condensate
11 pages, 3 figures; acknowledgements added; discussion added; version accepted for publication in PRD
Phys. Rev. D 110, 014511 (2024)
10.1103/PhysRevD.110.014511
null
hep-ph hep-lat hep-th
http://creativecommons.org/licenses/by/4.0/
We discuss the negativity of the moment of inertia of (quark-)gluon plasma in a window of "supervortical" range of temperatures above the deconfining phase transition, $T \simeq (1\dots 1.5) T_c $ found recently in numerical Monte Carlo simulations by two independent methods. In our work, we confirm numerically that the origin of this effect is rooted in the thermal evaporation of the non-perturbative chromomagnetic condensate. We argue that the negative moment of inertia of gluon plasma indicates the presence of a novel effect, the negative spin-vortical coupling for gluons resulting in a negative gluonic Barnett effect: the spin polarization of gluons exceeds the total angular momentum of rotating plasma, thus forcing the orbital angular momentum to take negative values in the supervortical range of temperatures.
[ { "created": "Tue, 24 Oct 2023 17:50:51 GMT", "version": "v1" }, { "created": "Tue, 26 Mar 2024 16:57:49 GMT", "version": "v2" }, { "created": "Wed, 24 Jul 2024 08:37:46 GMT", "version": "v3" } ]
2024-08-01
[ [ "Braguta", "Victor V.", "" ], [ "Chernodub", "Maxim N.", "" ], [ "Kudrov", "Ilya E.", "" ], [ "Roenko", "Artem A.", "" ], [ "Sychev", "Dmitrii A.", "" ] ]
We discuss the negativity of the moment of inertia of (quark-)gluon plasma in a window of "supervortical" range of temperatures above the deconfining phase transition, $T \simeq (1\dots 1.5) T_c $ found recently in numerical Monte Carlo simulations by two independent methods. In our work, we confirm numerically that the origin of this effect is rooted in the thermal evaporation of the non-perturbative chromomagnetic condensate. We argue that the negative moment of inertia of gluon plasma indicates the presence of a novel effect, the negative spin-vortical coupling for gluons resulting in a negative gluonic Barnett effect: the spin polarization of gluons exceeds the total angular momentum of rotating plasma, thus forcing the orbital angular momentum to take negative values in the supervortical range of temperatures.
1005.2756
V. Sreekanth
Jitesh R. Bhatt, Hiranmaya Mishra and V. Sreekanth
Cavitation and thermal photon production in relativistic heavy ion collisions
9 pages, 11 figures, title changed, Talk given by Sreekanth V. at International School and Workshop, Dense QCD Phases in Heavy-Ion Collisions, August 21st - September 4th, 2010 JINR Dubna, Russia
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the thermal photon production-rates using one dimensional boost-invariant second order relativistic hydrodynamics to find proper time evolution of the energy density and the temperature. The effect of bulk-viscosity and non-ideal equation of state are taken into account in a manner consistent with recent lattice QCD estimates. It is shown that the \textit{non-ideal} gas equation of state i.e $\epsilon-3 P \neq 0$ behaviour of the expanding plasma, which is important near the phase-transition point, can significantly slow down the hydrodynamic expansion and thereby increase the photon production-rates. Inclusion of the bulk viscosity may also have similar effect on the hydrodynamic evolution. However the effect of bulk viscosity is shown to be significantly lower than the \textit{non-ideal} gas equation of state. We also analyze the interesting phenomenon of bulk viscosity induced cavitation making the hydrodynamical description invalid. It is shown that ignoring the cavitiation phenomenon can lead to a very significant over estimation of the photon flux. It is argued that this feature could be relevant in studying signature of cavitation in relativistic heavy ion collisions.
[ { "created": "Sun, 16 May 2010 15:47:59 GMT", "version": "v1" }, { "created": "Mon, 8 Nov 2010 14:56:52 GMT", "version": "v2" } ]
2015-03-17
[ [ "Bhatt", "Jitesh R.", "" ], [ "Mishra", "Hiranmaya", "" ], [ "Sreekanth", "V.", "" ] ]
We investigate the thermal photon production-rates using one dimensional boost-invariant second order relativistic hydrodynamics to find proper time evolution of the energy density and the temperature. The effect of bulk-viscosity and non-ideal equation of state are taken into account in a manner consistent with recent lattice QCD estimates. It is shown that the \textit{non-ideal} gas equation of state i.e $\epsilon-3 P \neq 0$ behaviour of the expanding plasma, which is important near the phase-transition point, can significantly slow down the hydrodynamic expansion and thereby increase the photon production-rates. Inclusion of the bulk viscosity may also have similar effect on the hydrodynamic evolution. However the effect of bulk viscosity is shown to be significantly lower than the \textit{non-ideal} gas equation of state. We also analyze the interesting phenomenon of bulk viscosity induced cavitation making the hydrodynamical description invalid. It is shown that ignoring the cavitiation phenomenon can lead to a very significant over estimation of the photon flux. It is argued that this feature could be relevant in studying signature of cavitation in relativistic heavy ion collisions.
hep-ph/9507283
Atsushi Yamada
A. I. Sanda and Atsushi Yamada
A new method of determining $|V_{ub}|$ by the processes $\bar{B} \to \rho l \bar{\nu}$ and $\bar{B} \to K^* l \lbar$
Latex file 9 page
Phys.Rev.Lett. 75 (1995) 2807-2810
10.1103/PhysRevLett.75.2807
DPNU-95-17 and UT-709
hep-ph
null
The differential decay width of the process $\bar{B} \rightarrow \rho l \bar{\nu}$ is related to that of the process $\bar{B} \rightarrow K^* l \lbar$ by using $SU(3)$-flavor symmetry and the heavy quark symmetry. The ratio of the Kobayashi-Maskawa matrix elements is obtained in the zero recoil limit of $\rho$ and $K^*$, allowing a determination of $|V_{ub}|$.
[ { "created": "Tue, 11 Jul 1995 06:48:53 GMT", "version": "v1" } ]
2009-10-28
[ [ "Sanda", "A. I.", "" ], [ "Yamada", "Atsushi", "" ] ]
The differential decay width of the process $\bar{B} \rightarrow \rho l \bar{\nu}$ is related to that of the process $\bar{B} \rightarrow K^* l \lbar$ by using $SU(3)$-flavor symmetry and the heavy quark symmetry. The ratio of the Kobayashi-Maskawa matrix elements is obtained in the zero recoil limit of $\rho$ and $K^*$, allowing a determination of $|V_{ub}|$.
hep-ph/0603224
Feng-Quan Wu
F. Q. Wu and B. S. Zou
Subthreshold rho contribution in J/psi decay to omega pion pion and Kaon anti-Kaon pion
12 pages, 5 figures
Phys.Rev.D73:114008,2006
10.1103/PhysRevD.73.114008
null
hep-ph nucl-th
null
We carry out a theoretical and Monte Carlo study on the $J/\psi$ decays into $\omega\pi\pi$ and $K\bar{K}\pi$ through intermediate subthreshold $\rho$ meson by using SU(3)-symmetric Lagrangian approach. It is found that the subthreshold $\rho$ contribution is not negligible and may have significant influence on partial wave analysis of resonances in these channels, especially near the $\omega \pi$ and $K \bar{K}$ thresholds.
[ { "created": "Mon, 27 Mar 2006 14:44:53 GMT", "version": "v1" }, { "created": "Thu, 22 Jun 2006 08:39:54 GMT", "version": "v2" } ]
2008-11-26
[ [ "Wu", "F. Q.", "" ], [ "Zou", "B. S.", "" ] ]
We carry out a theoretical and Monte Carlo study on the $J/\psi$ decays into $\omega\pi\pi$ and $K\bar{K}\pi$ through intermediate subthreshold $\rho$ meson by using SU(3)-symmetric Lagrangian approach. It is found that the subthreshold $\rho$ contribution is not negligible and may have significant influence on partial wave analysis of resonances in these channels, especially near the $\omega \pi$ and $K \bar{K}$ thresholds.
hep-ph/0107169
Gi-Chol Cho
Gi-Chol Cho (Ochanomizu Univ.)
Muon g-2 and Minimal Supersymmetric Standard Model
15 pages, latex, 6 figures. Talk given at ``Theory Meeting on Physics at Linear Colliders'', Mar 15-17, 2001, KEK, Tsukuba, Japan
null
null
OCHA-PP-179
hep-ph
null
The supersymmetric contribution to the muon g-2 is studied in light of the finalization of the LEP electroweak precision data. The recent precise measurement of the muon g-2 of E821 experiment is explained well by the relatively light chargino and sleptons. We find that such the MSSM parameter space is also favored from the electroweak precision data, in which the fit to the data is better than that of the SM (\Delta \chi^2_{min} \sim -2), if the lighter chargino has a mixed higgsino-wino character (\mu/M_2 \sim 1). The models with light gauginos (\mu/M_2 > 10) or light higgsinos (\mu/M_2 < 0.1) also show the better fit over the SM, but the improvement is marginal as compared to the case of the mixed higgsino-wino case (\mu/M_2 \sim 1).
[ { "created": "Mon, 16 Jul 2001 07:18:45 GMT", "version": "v1" } ]
2007-05-23
[ [ "Cho", "Gi-Chol", "", "Ochanomizu Univ." ] ]
The supersymmetric contribution to the muon g-2 is studied in light of the finalization of the LEP electroweak precision data. The recent precise measurement of the muon g-2 of E821 experiment is explained well by the relatively light chargino and sleptons. We find that such the MSSM parameter space is also favored from the electroweak precision data, in which the fit to the data is better than that of the SM (\Delta \chi^2_{min} \sim -2), if the lighter chargino has a mixed higgsino-wino character (\mu/M_2 \sim 1). The models with light gauginos (\mu/M_2 > 10) or light higgsinos (\mu/M_2 < 0.1) also show the better fit over the SM, but the improvement is marginal as compared to the case of the mixed higgsino-wino case (\mu/M_2 \sim 1).
hep-ph/9307344
Robert Shrock
Alexander Kusenko and Robert Shrock
A New Model for Fermion Masses in Supersymmetric Grand Unified Theories
Latex, 8 p., ITP-SB-93-37 (revised version contains minor changes in some wording and citations; no changes in analytic or numerical results.)
Phys.Rev.D49:4962-4965,1994
10.1103/PhysRevD.49.4962
null
hep-ph
null
We present a simple model for fermion mass matrices and quark mixing in the context of supersymmetric grand unified theories and show its agreement with experiment. Our model realizes the GUT mass relations $m_d=3m_e$, $m_s= m_\mu/3$, $m_b=m_\tau$ in a new way and is easily consistent with values of $m_t$ suggested by MSSM fits to LEP data.
[ { "created": "Tue, 27 Jul 1993 18:46:28 GMT", "version": "v1" }, { "created": "Sun, 1 Aug 1993 21:35:06 GMT", "version": "v2" } ]
2010-11-01
[ [ "Kusenko", "Alexander", "" ], [ "Shrock", "Robert", "" ] ]
We present a simple model for fermion mass matrices and quark mixing in the context of supersymmetric grand unified theories and show its agreement with experiment. Our model realizes the GUT mass relations $m_d=3m_e$, $m_s= m_\mu/3$, $m_b=m_\tau$ in a new way and is easily consistent with values of $m_t$ suggested by MSSM fits to LEP data.