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1807.03805
Yusuf Gunaydin
Ahmet Nuri Akay (TOBB ETU), Yusuf Oguzhan G\"unaydin (Kahrmanmaras Sutcu Imam University), Mehmet Sahin (Usak University), Saleh Sultansoy (TOBB ETU)
Search for Excited $u$ and $d$ Quarks in Dijet Final States at Future $pp$ Colliders
16 pages, 7 figures, 5 tables
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Resonant production of excited $u$ and $d$ quarks at the Future Circular Collider and Super proton-proton Collider have been researched. Dominant jet-jet decay mode has been considered. It is shown that FCC and SppC have great potential for discovery of excited $u$ ($d$) quark: up to 44.1 (36.3) and 58.4 (47.8) TeV masses, respectively. For degenerate case (M$_{u^{\star}}$ = M$_{d^{\star}}$), these values are 45.9 and 60.9 TeV, respectively. This discovery will also afford an opportunity to determine the compositeness scale up to multi-PeV level.
[ { "created": "Tue, 10 Jul 2018 18:10:57 GMT", "version": "v1" }, { "created": "Mon, 16 Jul 2018 17:52:03 GMT", "version": "v2" }, { "created": "Wed, 18 Jul 2018 12:44:43 GMT", "version": "v3" }, { "created": "Mon, 22 Oct 2018 18:15:06 GMT", "version": "v4" }, { "created": "Mon, 25 Feb 2019 18:17:21 GMT", "version": "v5" } ]
2019-02-26
[ [ "Akay", "Ahmet Nuri", "", "TOBB ETU" ], [ "Günaydin", "Yusuf Oguzhan", "", "Kahrmanmaras\n Sutcu Imam University" ], [ "Sahin", "Mehmet", "", "Usak University" ], [ "Sultansoy", "Saleh", "", "TOBB\n ETU" ] ]
Resonant production of excited $u$ and $d$ quarks at the Future Circular Collider and Super proton-proton Collider have been researched. Dominant jet-jet decay mode has been considered. It is shown that FCC and SppC have great potential for discovery of excited $u$ ($d$) quark: up to 44.1 (36.3) and 58.4 (47.8) TeV masses, respectively. For degenerate case (M$_{u^{\star}}$ = M$_{d^{\star}}$), these values are 45.9 and 60.9 TeV, respectively. This discovery will also afford an opportunity to determine the compositeness scale up to multi-PeV level.
2107.07609
Mikhail Ryskin G
M.G. Ryskin
Two photon exchange contribution to small angle $\mu p$ and $ep$ elastic scattering
null
null
null
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
We consider the role of the two-photon corrections to the small angle $\mu p$ and $ep$ elastic scattering and the expected $\sigma(\mu^- p)/\sigma(\mu^+ p)$ ratio.
[ { "created": "Tue, 13 Jul 2021 07:49:34 GMT", "version": "v1" } ]
2021-07-19
[ [ "Ryskin", "M. G.", "" ] ]
We consider the role of the two-photon corrections to the small angle $\mu p$ and $ep$ elastic scattering and the expected $\sigma(\mu^- p)/\sigma(\mu^+ p)$ ratio.
hep-ph/9705220
null
A. J. Baltz (BNL), Mark Strikman (Penn. State U.)
Suppression of Heavy Ion gamma gamma Production of the Higgs by Coulomb Dissociation
5 pages, latex, revtex source, two postscript figures
Phys.Rev. D57 (1998) 548-549
10.1103/PhysRevD.57.548
null
hep-ph
null
Predicted two-photon Higgs production with heavy ions at LHC is shown to be reduced due to the large Coulomb dissociation cross section. Incorporating the effect of dissociation reduces the production of a 100 GeV Higgs by about a factor of three compared to rates in the literature calculated without this effect.
[ { "created": "Fri, 2 May 1997 20:29:14 GMT", "version": "v1" } ]
2009-10-30
[ [ "Baltz", "A. J.", "", "BNL" ], [ "Strikman", "Mark", "", "Penn. State U." ] ]
Predicted two-photon Higgs production with heavy ions at LHC is shown to be reduced due to the large Coulomb dissociation cross section. Incorporating the effect of dissociation reduces the production of a 100 GeV Higgs by about a factor of three compared to rates in the literature calculated without this effect.
hep-ph/9310281
null
S. Dawson and R. Kauffman (BNL)
QCD Corrections to Higgs Boson Production: Non- Leading Terms in the Heavy Quark Limit
27 pages plus 8 figures in uuencoded tar-compressed format, BNL-DK1
Phys.Rev. D49 (1994) 2298-2309
10.1103/PhysRevD.49.2298
null
hep-ph
null
We compute analytic results for the QCD corrections to Higgs boson production via gluon fusion in hadronic collisions in the limit in which the top quark is much heavier than the Higgs boson. The first non-leading corrections of $\O(\alpha_s^3 \mh^2/m_t^2)$ are given and numerical results presented for both LHC and SSC energies. We confirm earlier numerical results showing that the dominant corrections have the same mass dependence as the Born cross section.
[ { "created": "Wed, 13 Oct 1993 18:12:50 GMT", "version": "v1" } ]
2009-10-22
[ [ "Dawson", "S.", "", "BNL" ], [ "Kauffman", "R.", "", "BNL" ] ]
We compute analytic results for the QCD corrections to Higgs boson production via gluon fusion in hadronic collisions in the limit in which the top quark is much heavier than the Higgs boson. The first non-leading corrections of $\O(\alpha_s^3 \mh^2/m_t^2)$ are given and numerical results presented for both LHC and SSC energies. We confirm earlier numerical results showing that the dominant corrections have the same mass dependence as the Born cross section.
hep-ph/0101304
Nigel Glover
C. Anastasiou, E.W.N. Glover, C. Oleari and M.E. Tejeda-Yeomans
Two-loop QCD corrections to massless quark-gluon scattering
32 pages, LaTeX, JHEP class, typo in Eq.4.6 fixed, typo in Eq 3.2 fixed
Nucl.Phys.B605:486-516,2001
10.1016/S0550-3213(01)00195-X
DCTP/01/04, IPPP/01/02, MADPH-00-1210
hep-ph
null
We present the O(alphas^4) virtual QCD corrections to the scattering process of massless quark qqbar -> gg due to the interference of tree and two-loop amplitudes and to the self-interference of one-loop amplitudes. We work in conventional dimensional regularisation and our results are renormalised in the MSbar scheme. The structure of the infrared divergences agrees with that predicted by Catani while expressions for the finite remainder are given for the qqbar -> gg and the qg -> qg (gqbar -> gqbar) scattering processes in terms of logarithms and polylogarithms that are real in the physical region. These results, together with those previously obtained for quark-quark scattering, are important ingredients in the next-to-next-to-leading order contribution to inclusive jet production at hadron colliders.
[ { "created": "Fri, 26 Jan 2001 22:19:37 GMT", "version": "v1" }, { "created": "Fri, 7 Dec 2001 12:47:49 GMT", "version": "v2" }, { "created": "Tue, 6 May 2003 09:43:39 GMT", "version": "v3" }, { "created": "Fri, 29 Jun 2007 12:46:40 GMT", "version": "v4" } ]
2008-11-26
[ [ "Anastasiou", "C.", "" ], [ "Glover", "E. W. N.", "" ], [ "Oleari", "C.", "" ], [ "Tejeda-Yeomans", "M. E.", "" ] ]
We present the O(alphas^4) virtual QCD corrections to the scattering process of massless quark qqbar -> gg due to the interference of tree and two-loop amplitudes and to the self-interference of one-loop amplitudes. We work in conventional dimensional regularisation and our results are renormalised in the MSbar scheme. The structure of the infrared divergences agrees with that predicted by Catani while expressions for the finite remainder are given for the qqbar -> gg and the qg -> qg (gqbar -> gqbar) scattering processes in terms of logarithms and polylogarithms that are real in the physical region. These results, together with those previously obtained for quark-quark scattering, are important ingredients in the next-to-next-to-leading order contribution to inclusive jet production at hadron colliders.
hep-ph/0103339
Dimitri Melikhov
A. Le Yaouanc, D. Melikhov, V. Morenas, L. Oliver, O. Pene, J.-C. Raynal
Duality in semileptonic inclusive B-decays in potential models: regular versus singular potentials
revtex, 6 pages
Phys.Lett. B517 (2001) 135-141
10.1016/S0370-2693(01)00963-7
null
hep-ph
null
Making use of the nonrelativistic potential model for the description of mesons, and working in the Shifman-Voloshin limit, we compare the integrated rate $\Gamma(B\to X_cl\nu)$ calculated as a sum of the individual decay rates to the quantum-mechanical analog of the OPE. In the case of a potential regular at the origin, we find a well-defined duality violation, which is however exponentially small. It corresponds to the charm resonances kinematically forbidden in the decay process, but apparently picked up by the OPE. For singular potentials, we do not obtain a full OPE series, but only a limited Taylor expansion, since the cofficients become infinite beyond some order. In this case, we do not find an indication of duality violation: the difference is smaller than the last term of the limited expansion. This emphasizes that the case of singular potentials, which may be relevant for QCD, deserves further study.
[ { "created": "Fri, 30 Mar 2001 14:46:21 GMT", "version": "v1" } ]
2009-11-07
[ [ "Yaouanc", "A. Le", "" ], [ "Melikhov", "D.", "" ], [ "Morenas", "V.", "" ], [ "Oliver", "L.", "" ], [ "Pene", "O.", "" ], [ "Raynal", "J. -C.", "" ] ]
Making use of the nonrelativistic potential model for the description of mesons, and working in the Shifman-Voloshin limit, we compare the integrated rate $\Gamma(B\to X_cl\nu)$ calculated as a sum of the individual decay rates to the quantum-mechanical analog of the OPE. In the case of a potential regular at the origin, we find a well-defined duality violation, which is however exponentially small. It corresponds to the charm resonances kinematically forbidden in the decay process, but apparently picked up by the OPE. For singular potentials, we do not obtain a full OPE series, but only a limited Taylor expansion, since the cofficients become infinite beyond some order. In this case, we do not find an indication of duality violation: the difference is smaller than the last term of the limited expansion. This emphasizes that the case of singular potentials, which may be relevant for QCD, deserves further study.
hep-ph/0406032
Robert Shrock
Thomas Appelquist, Maurizio Piai, and Robert Shrock
Quark Dipole Operators in Extended Technicolor Models
9 pages, latex
Phys.Lett. B595 (2004) 442-452
10.1016/j.physletb.2004.06.066
null
hep-ph hep-ex
null
We study diagonal and transition quark dipole operators in a class of extended technicolor (ETC) models, taking account of the multiscale nature of the ETC gauge symmetry breaking and of the mixing among ETC interaction eigenstates. Because of this mixing, terms involving the lowest ETC scale can play an important role in dipole operators, and we focus on these terms. We derive from experiment new correlated constraints on the quark mixing angles and phases. Our bounds yield information on mixing angles individually in the up- and down-sectors, for both left- and right-handed quark fields and thus constrain even quark mixing parameters that do not enter in the CKM matrix. With phases of order unity, we conclude that these mixing angles are small, constraining future ETC model building, but plausibly in the range suggested by the size of the CKM elements. These values still allow substantial deviations from the standard model predictions, in particular for several CP violating quantities, including the asymmetries in $b \to s \gamma$ and $B_{d} \to \phi K_S$, $Re(\epsilon^\prime/\epsilon)$, and the electric dipole moments of the neutron and the ${}^{199}$Hg atom.
[ { "created": "Wed, 2 Jun 2004 20:43:22 GMT", "version": "v1" }, { "created": "Fri, 11 Jun 2004 17:17:04 GMT", "version": "v2" } ]
2009-11-10
[ [ "Appelquist", "Thomas", "" ], [ "Piai", "Maurizio", "" ], [ "Shrock", "Robert", "" ] ]
We study diagonal and transition quark dipole operators in a class of extended technicolor (ETC) models, taking account of the multiscale nature of the ETC gauge symmetry breaking and of the mixing among ETC interaction eigenstates. Because of this mixing, terms involving the lowest ETC scale can play an important role in dipole operators, and we focus on these terms. We derive from experiment new correlated constraints on the quark mixing angles and phases. Our bounds yield information on mixing angles individually in the up- and down-sectors, for both left- and right-handed quark fields and thus constrain even quark mixing parameters that do not enter in the CKM matrix. With phases of order unity, we conclude that these mixing angles are small, constraining future ETC model building, but plausibly in the range suggested by the size of the CKM elements. These values still allow substantial deviations from the standard model predictions, in particular for several CP violating quantities, including the asymmetries in $b \to s \gamma$ and $B_{d} \to \phi K_S$, $Re(\epsilon^\prime/\epsilon)$, and the electric dipole moments of the neutron and the ${}^{199}$Hg atom.
hep-ph/0001179
Sacha Davidson
Sacha Davidson, Steen Hannestad, Georg Raffelt
Updated Bounds on Milli-Charged Particles
15 pages, 1 figure, minor changes, matches version to be published in JHEP
JHEP 0005:003,2000
10.1088/1126-6708/2000/05/003
CERN-TH/99-384
hep-ph
null
We update the bounds on fermions with electric charge $\epsilon e$ and mass $m_\epsilon$. For $m_\epsilon\lsim m_e$ we find $10^{-15}\lsim\epsilon<1$ is excluded by laboratory experiments, astrophysics and cosmology. For larger masses, the limits are less restrictive and depend on $m_\epsilon$. For milli-charged neutrinos, the limits are stronger, especially if the different flavors mix as suggested by current experimental evidence.
[ { "created": "Tue, 18 Jan 2000 11:07:06 GMT", "version": "v1" }, { "created": "Tue, 2 May 2000 07:52:01 GMT", "version": "v2" } ]
2010-04-06
[ [ "Davidson", "Sacha", "" ], [ "Hannestad", "Steen", "" ], [ "Raffelt", "Georg", "" ] ]
We update the bounds on fermions with electric charge $\epsilon e$ and mass $m_\epsilon$. For $m_\epsilon\lsim m_e$ we find $10^{-15}\lsim\epsilon<1$ is excluded by laboratory experiments, astrophysics and cosmology. For larger masses, the limits are less restrictive and depend on $m_\epsilon$. For milli-charged neutrinos, the limits are stronger, especially if the different flavors mix as suggested by current experimental evidence.
1712.02132
Shigeru Odaka
Shigeru Odaka and Yoshimasa Kurihara
GR@PPA 2.9: radiation matching for simulating photon production processes in hadron collisions
11 pages
null
10.1016/j.cpc.2018.05.018
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We release an event generator package, GR@PPA 2.9, for simulating the direct (single) photon and diphoton (double photon) production in hadron collisions. The included programs were used in our previous studies, in which we have explicitly shown large contributions from parton-associated processes. The programs consistently combine simulations based on matrix elements with parton-shower simulations that reproduce the multiple parton radiation and quark fragmentation to photons. The matrix elements include associated parton production processes up to two partons. We provide instructions for the installation and execution of the programs in this article. The practical performance is also presented.
[ { "created": "Wed, 6 Dec 2017 11:15:10 GMT", "version": "v1" }, { "created": "Tue, 19 Jun 2018 02:42:01 GMT", "version": "v2" } ]
2018-08-15
[ [ "Odaka", "Shigeru", "" ], [ "Kurihara", "Yoshimasa", "" ] ]
We release an event generator package, GR@PPA 2.9, for simulating the direct (single) photon and diphoton (double photon) production in hadron collisions. The included programs were used in our previous studies, in which we have explicitly shown large contributions from parton-associated processes. The programs consistently combine simulations based on matrix elements with parton-shower simulations that reproduce the multiple parton radiation and quark fragmentation to photons. The matrix elements include associated parton production processes up to two partons. We provide instructions for the installation and execution of the programs in this article. The practical performance is also presented.
hep-ph/0207091
A. Onishchenko
A.Onishchenko, O.Veretin
Special case of sunset: reduction and epsilon-expansion
LaTeX, 13 pages, 1 figure
Phys.Atom.Nucl. 68 (2005) 1405-1413; Yad.Fiz. 68 (2005) 1461-1469
10.1134/1.2011500
TTP02-15
hep-ph
null
We consider two loop sunset diagrams with two mass scales m and M at the threshold and pseudotreshold that cannot be treated by earlier published formula. The complete reduction to master integrals is given. The master integrals are evaluated as series in ratio m/M and in epsilon with the help of differential equation method. The rules of asymptotic expansion in the case when q^2 is at the (pseudo)threshold are given.
[ { "created": "Fri, 5 Jul 2002 17:02:07 GMT", "version": "v1" } ]
2015-06-25
[ [ "Onishchenko", "A.", "" ], [ "Veretin", "O.", "" ] ]
We consider two loop sunset diagrams with two mass scales m and M at the threshold and pseudotreshold that cannot be treated by earlier published formula. The complete reduction to master integrals is given. The master integrals are evaluated as series in ratio m/M and in epsilon with the help of differential equation method. The rules of asymptotic expansion in the case when q^2 is at the (pseudo)threshold are given.
hep-ph/0202148
Miranda van Iersel
M. van Iersel, B.L.G. Bakker, and F. Pijlman
Relativistic bound-state calculations in Light Front Dynamics
3 pages, proceedings of the Light Cone Meeting Trento 2001, to be published in Nucl. Phys. B - Proceedings Supplements
Nucl.Phys.Proc.Suppl. 108 (2002) 270-272
10.1016/S0920-5632(02)01343-9
null
hep-ph
null
We calculated bound states in the quantum field theoretical approach. Using the Wick-Cutkosky model and an extended version of this model (in which a particle with finite mass is exchanged) we have calculated the bound states in the scalar case.
[ { "created": "Fri, 15 Feb 2002 13:31:46 GMT", "version": "v1" } ]
2009-11-07
[ [ "van Iersel", "M.", "" ], [ "Bakker", "B. L. G.", "" ], [ "Pijlman", "F.", "" ] ]
We calculated bound states in the quantum field theoretical approach. Using the Wick-Cutkosky model and an extended version of this model (in which a particle with finite mass is exchanged) we have calculated the bound states in the scalar case.
1609.06113
Hiroyuki Ishida
Takehiko Asaka and Hiroyuki Ishida
Lepton number violation by heavy Majorana neutrino in $B$ decays
11 pages, 2 figures (Figure 2 is revised), v2: version to appear in Physics Letters B
null
10.1016/j.physletb.2016.10.070
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Heavy Majorana neutrinos are predicted in addition to ordinary active neutrinos in the models with the seesaw mechanism. We investigate the lepton number violation (LNV) in $B$ decays induced by such a heavy neutrino $N$ with GeV-scale mass. Especially, we consider the decay channel $B^+ \to \mu^+ \, N \to \mu^+ \mu^+ \pi^-$ and derive the sensitivity limits on the mixing angle $\Theta_\mu$ by the future search experiments at Belle II and in $e^+ e^-$ collisions at the Future Circular Collider (FCC-ee).
[ { "created": "Tue, 20 Sep 2016 11:40:28 GMT", "version": "v1" }, { "created": "Thu, 10 Nov 2016 06:37:09 GMT", "version": "v2" } ]
2016-11-11
[ [ "Asaka", "Takehiko", "" ], [ "Ishida", "Hiroyuki", "" ] ]
Heavy Majorana neutrinos are predicted in addition to ordinary active neutrinos in the models with the seesaw mechanism. We investigate the lepton number violation (LNV) in $B$ decays induced by such a heavy neutrino $N$ with GeV-scale mass. Especially, we consider the decay channel $B^+ \to \mu^+ \, N \to \mu^+ \mu^+ \pi^-$ and derive the sensitivity limits on the mixing angle $\Theta_\mu$ by the future search experiments at Belle II and in $e^+ e^-$ collisions at the Future Circular Collider (FCC-ee).
1001.1378
Javier L. Albacete
Javier L. Albacete and Cyrille Marquet
Single Inclusive Hadron Production at RHIC and the LHC from the Color Glass Condensate
Abstract and 3 figures modified
Phys.Lett.B687:174-179,2010
10.1016/j.physletb.2010.02.073
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using the unintegrated gluon distribution obtained from numerical simulations of the Balitsky-Kovchegov equation with running coupling, we obtain a very good description of RHIC data on single inclusive hadron production at forward rapidities in both p+p and d+Au collisions. No K-factors are needed for charged hadrons, whereas for pion production a rapidity independent K-factor of order 1/3 is needed. Extrapolating to LHC energies, we calculate nuclear modification factors for light hadrons in p+Pb collision, as well as the contribution of initial state effects to the suppression of the nuclear modification factor in Pb+Pb collisions.
[ { "created": "Fri, 8 Jan 2010 22:58:32 GMT", "version": "v1" }, { "created": "Thu, 28 Jan 2010 08:13:08 GMT", "version": "v2" } ]
2010-05-28
[ [ "Albacete", "Javier L.", "" ], [ "Marquet", "Cyrille", "" ] ]
Using the unintegrated gluon distribution obtained from numerical simulations of the Balitsky-Kovchegov equation with running coupling, we obtain a very good description of RHIC data on single inclusive hadron production at forward rapidities in both p+p and d+Au collisions. No K-factors are needed for charged hadrons, whereas for pion production a rapidity independent K-factor of order 1/3 is needed. Extrapolating to LHC energies, we calculate nuclear modification factors for light hadrons in p+Pb collision, as well as the contribution of initial state effects to the suppression of the nuclear modification factor in Pb+Pb collisions.
1003.4937
Jose Rodriguez-Quintero
M.E. G\'omez, S. Lola, P. Naranjo, J. Rodr\'iguez-Quintero
Suppression of Lepton Flavour Violation from Quantum Corrections above $M_{GUT}$
15 pages, 5 figs.
JHEP 1006:053,2010
10.1007/JHEP06(2010)053
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the predictions for sfermion masses and Lepton Flavour Violation (LFV) for the WMAP preferred parameter space in $b-\tau$ Yukawa-unified models with massive neutrinos. A soft term structure as predicted by an Abelian flavour symmetry combined with SU(5) RGEs for scales above $M_{GUT}$, results to an efficient suppression of the off-diagonal terms in the scalar soft matrices, particularly for $m_0< 100$ GeV. Using the WMAP bounds, this implies $35\le\tan\beta \le 45$, $350\,\mathrm{GeV}\le m_{1/2}\le 1\,\mathrm{TeV}$, with the higher $\tan\beta$ values being favored. Within this framework, SU(5) unification becomes compatible with the current experimental bounds, in contrast to the conventional case where the soft terms are postulated at the GUT scale.
[ { "created": "Thu, 25 Mar 2010 15:40:15 GMT", "version": "v1" } ]
2015-03-13
[ [ "Gómez", "M. E.", "" ], [ "Lola", "S.", "" ], [ "Naranjo", "P.", "" ], [ "Rodríguez-Quintero", "J.", "" ] ]
We study the predictions for sfermion masses and Lepton Flavour Violation (LFV) for the WMAP preferred parameter space in $b-\tau$ Yukawa-unified models with massive neutrinos. A soft term structure as predicted by an Abelian flavour symmetry combined with SU(5) RGEs for scales above $M_{GUT}$, results to an efficient suppression of the off-diagonal terms in the scalar soft matrices, particularly for $m_0< 100$ GeV. Using the WMAP bounds, this implies $35\le\tan\beta \le 45$, $350\,\mathrm{GeV}\le m_{1/2}\le 1\,\mathrm{TeV}$, with the higher $\tan\beta$ values being favored. Within this framework, SU(5) unification becomes compatible with the current experimental bounds, in contrast to the conventional case where the soft terms are postulated at the GUT scale.
hep-ph/0310135
Antonio Pineda
Antonio Pineda
Is there a linear potential at short distances?
6 pages, 5 figures, Invited talk given at QCD03, 2-9 July, Montpellier, France
null
10.1016/j.nuclphysbps.2004.04.163
UB-ECM-PF 03/25
hep-ph hep-lat hep-th
null
We argue that the lattice data of the static potential can be explained by perturbation theory up to energies of the order of 1 GeV once renormalons effects are taken into account
[ { "created": "Fri, 10 Oct 2003 16:29:03 GMT", "version": "v1" } ]
2009-11-10
[ [ "Pineda", "Antonio", "" ] ]
We argue that the lattice data of the static potential can be explained by perturbation theory up to energies of the order of 1 GeV once renormalons effects are taken into account
hep-ph/0304288
Ying Li
Ying Li, Cai-Dian Lu
Study of pure annihilation type decays $B \to D_s^{*} K$
14 pages, 1 figure
J.Phys.G29:2115-2124,2003
10.1088/0954-3899/29/9/307
null
hep-ph
null
In this work, we calculate the rare decays $B^0 \to D_s^{*-} K^+$ and $B^+ \to D_s^{*+} \bar{K}^0$ in perturbative QCD approach with Sudakov resummation. We give the branching ratio of $10^{-5}$ for $B^0 \to D_s^{*-}K^+$, which will be tested soon in $B$ factories. The decay $B^+ \to D_s^{*+} \bar{K}^0$ has a very small branching ratio at ${\cal O}(10^{-8})$, due to the suppression from CKM matrix elements $|V_{ub}^* V_{cd}|$. It may be sensitive to new physics contributions.
[ { "created": "Wed, 30 Apr 2003 12:26:05 GMT", "version": "v1" } ]
2008-11-26
[ [ "Li", "Ying", "" ], [ "Lu", "Cai-Dian", "" ] ]
In this work, we calculate the rare decays $B^0 \to D_s^{*-} K^+$ and $B^+ \to D_s^{*+} \bar{K}^0$ in perturbative QCD approach with Sudakov resummation. We give the branching ratio of $10^{-5}$ for $B^0 \to D_s^{*-}K^+$, which will be tested soon in $B$ factories. The decay $B^+ \to D_s^{*+} \bar{K}^0$ has a very small branching ratio at ${\cal O}(10^{-8})$, due to the suppression from CKM matrix elements $|V_{ub}^* V_{cd}|$. It may be sensitive to new physics contributions.
1308.6039
Chilong Lin
Chilong Lin
Theoretical Origin of CP Violation in a Special FCNC-Free 2HDM with $S_N$ Symmetries
6 pages
null
null
NMNS/HEPPH-1301
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this manuscript, a way solves the FCNC problem in 2HDM radically and leads to CP violation explicitly is demonstrated. The derivation starts from a most general $3 \times 3$ mass matrix $M$ containing eighteen parameters, which applies to all fermion types, and then reduces the number of parameters down to five with a Hermitian condition modified in this manuscript between the real part and imaginary part of $M$. All matrix pairs thus derived will be diagonalized simultaneously by a same $U$ matrix which means FCNCs won't appear at tree-level anymore. Subsequently, an assumption of $A=A_1=A_2=A_3$ is imposed and four special solutions are thus found which reveal $S_3$ and $S_2$ symmetries among fermion generations respectively. Consequently, as a by-product of solving the FCNC problem, complex CKM matrices appear if the symmetries were assigned to up- and down-type quarks suitably. Unfortunately, CKM elements thus derived are very different to the experimentally detected values. The CP strength of this model, estimated by the Jarlskog invariant, is four orders higher than the one predicted by the standard model. This difference is in fact reasonable since we don't see any such symmetries in our present universe. However, if they had appeared in some early stages of our universe, such a strong CP strength may provide a way to account for at least part of the discrepancy between the observed BAU and that predicted by the standard model.
[ { "created": "Wed, 28 Aug 2013 03:05:08 GMT", "version": "v1" }, { "created": "Sat, 15 Sep 2018 10:59:39 GMT", "version": "v2" }, { "created": "Wed, 7 Nov 2018 07:02:07 GMT", "version": "v3" } ]
2018-11-08
[ [ "Lin", "Chilong", "" ] ]
In this manuscript, a way solves the FCNC problem in 2HDM radically and leads to CP violation explicitly is demonstrated. The derivation starts from a most general $3 \times 3$ mass matrix $M$ containing eighteen parameters, which applies to all fermion types, and then reduces the number of parameters down to five with a Hermitian condition modified in this manuscript between the real part and imaginary part of $M$. All matrix pairs thus derived will be diagonalized simultaneously by a same $U$ matrix which means FCNCs won't appear at tree-level anymore. Subsequently, an assumption of $A=A_1=A_2=A_3$ is imposed and four special solutions are thus found which reveal $S_3$ and $S_2$ symmetries among fermion generations respectively. Consequently, as a by-product of solving the FCNC problem, complex CKM matrices appear if the symmetries were assigned to up- and down-type quarks suitably. Unfortunately, CKM elements thus derived are very different to the experimentally detected values. The CP strength of this model, estimated by the Jarlskog invariant, is four orders higher than the one predicted by the standard model. This difference is in fact reasonable since we don't see any such symmetries in our present universe. However, if they had appeared in some early stages of our universe, such a strong CP strength may provide a way to account for at least part of the discrepancy between the observed BAU and that predicted by the standard model.
hep-ph/9508347
Marco Stratmann
M. Gluck, E. Reya, M. Stratmann (Univ. Dortmund), W. Vogelsang (Rutherford)
Next-to-Leading Order Radiative Parton Model Analysis of Polarized Deep Inelastic Scattering
34 pages, LaTeX, 9 figures; Only quantitative results of the original paper have been changed for two reasons: (1) small errors in the calculation of the NLO anom. dimensions (ref. 11); (2) inclusion of new data. Previous LO results (ref. 1) have also been updated
Phys.Rev. D53 (1996) 4775-4786
10.1103/PhysRevD.53.4775
DO-TH 95/13, RAL-TR-95-042
hep-ph
null
A next-to-leading order QCD analysis of spin asymmetries and structure functions in polarized deep inelastic lepton nucleon scattering is presented within the framework of the radiative parton model. A consistent NLO formulation of the $Q^2$-evolution of polarized parton distributions yields two sets of plausible NLO spin dependent parton distributions in the conventional $\overline{\rm{MS}}$ factorization scheme. They respect the fundamental positivity constraints down to the low resolution scale $Q^2=\mu^2_{NLO}=0.34\,{\rm{GeV}}^2$. The $Q^2$-dependence of the spin asymmetries $A_1^{p,n,d}(x,Q^2)$ is similar to the leading-order (LO) one in the range $1\le Q^2\le 20\,{\rm{GeV}}^2$ and is shown to be non-negligible for $x$-values relevant for the analysis of the present data and possibly forthcoming data at HERA.
[ { "created": "Tue, 22 Aug 1995 17:16:01 GMT", "version": "v1" }, { "created": "Tue, 9 Jan 1996 16:46:04 GMT", "version": "v2" } ]
2009-10-28
[ [ "Gluck", "M.", "", "Univ. Dortmund" ], [ "Reya", "E.", "", "Univ. Dortmund" ], [ "Stratmann", "M.", "", "Univ. Dortmund" ], [ "Vogelsang", "W.", "", "Rutherford" ] ]
A next-to-leading order QCD analysis of spin asymmetries and structure functions in polarized deep inelastic lepton nucleon scattering is presented within the framework of the radiative parton model. A consistent NLO formulation of the $Q^2$-evolution of polarized parton distributions yields two sets of plausible NLO spin dependent parton distributions in the conventional $\overline{\rm{MS}}$ factorization scheme. They respect the fundamental positivity constraints down to the low resolution scale $Q^2=\mu^2_{NLO}=0.34\,{\rm{GeV}}^2$. The $Q^2$-dependence of the spin asymmetries $A_1^{p,n,d}(x,Q^2)$ is similar to the leading-order (LO) one in the range $1\le Q^2\le 20\,{\rm{GeV}}^2$ and is shown to be non-negligible for $x$-values relevant for the analysis of the present data and possibly forthcoming data at HERA.
1505.00630
S. Weinzierl
Stefan Weinzierl
Precision on the top mass
9 pages, talk presented at the 50th Rencontres de Moriond EW 2015
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this talk I will focus on theoretical issues related to high precision determinations of the top mass. Several mass definitions are reviewed and their respective advantages and disadvantages are discussed. Precision determinations of the top mass will require a short-distance mass definition. I will summarise current work in this direction.
[ { "created": "Mon, 4 May 2015 13:41:03 GMT", "version": "v1" } ]
2015-05-05
[ [ "Weinzierl", "Stefan", "" ] ]
In this talk I will focus on theoretical issues related to high precision determinations of the top mass. Several mass definitions are reviewed and their respective advantages and disadvantages are discussed. Precision determinations of the top mass will require a short-distance mass definition. I will summarise current work in this direction.
1609.01787
Melina Gomez Bock
R. Espinosa-Casta\~neda, F.V. Flores-Baez, M. G\'omez-Bock and M. Mondrag\'on
Lepton flavor violation in an extended MSSM
8 pages, 1 figure, To be published in Journal of Physics Conference Series (IOP). Joint Proceedings of the XV Mexican Workshop on Particles and Fields & the XXX Annual Meeting of the Division of Particles and Fields of the Mexican Physical Society
null
10.1088/1742-6596/761/1/012062
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we explore a lepton flavor violation effect induced at one loop for a flavor structure in an extended minimal standard supersymmetric model, considering an ansatz for the trilinear term. In particular we find a finite expression which will show the impact of this phenomena in the $h\to \mu \tau$ decay, produced by a mixing in the trilinear coupling of the soft supersymmetric Lagrangian.
[ { "created": "Tue, 6 Sep 2016 23:49:14 GMT", "version": "v1" } ]
2016-11-23
[ [ "Espinosa-Castañeda", "R.", "" ], [ "Flores-Baez", "F. V.", "" ], [ "Gómez-Bock", "M.", "" ], [ "Mondragón", "M.", "" ] ]
In this work we explore a lepton flavor violation effect induced at one loop for a flavor structure in an extended minimal standard supersymmetric model, considering an ansatz for the trilinear term. In particular we find a finite expression which will show the impact of this phenomena in the $h\to \mu \tau$ decay, produced by a mixing in the trilinear coupling of the soft supersymmetric Lagrangian.
hep-ph/9907233
TingLiang Zhuang
T.-L. Zhuang, X. -J. Wang and M.-L. Yan
The Radiative Decay of Vector Mesons
Revtex file, 12 pages, 9 eps figures
Phys.Rev. D62 (2000) 053007
10.1103/PhysRevD.62.053007
null
hep-ph
null
In this paper, radiative decays $\rho^0 \to \pi^+\pi^-\gamma, \pi^0\pi^0\gamma$ ,$\phi \to K^+K^-\gamma, K^0 \bar{K^0}\gamma$ are studied systematically in the U(3)$_L\timesU(3)_R$ chiral theory of mesons. The theoretical differential spectrum with respect to photon energy and branch ratio for $\rho^0 \to \pi^+\pi^-\gamma$ agree well with the experimental data. Differential spectrums and branch ratios for $\rho^0 \to \pi^0\pi^0\gamma, \phi \to K^+ K^-\gamma,\phi \to K^0\bar{K^0}\gamma$ are predicted. The process $\phi \to K^0 \bar{K^0} \gamma$ is relevant to precision measurment of CP-violation parameters in the kaon systerm at a $\phi$-factory. We give a complete estimate of the branch ratio for this decay process by including scalar resonance $f_0, a_0$ poles, nonresonant smooth amplitude and an abnormal parity process with $K^*$ pole which hasn't been considered before. We conclude that processes with intermediate $K^*$ do not pose a potential background problem for $\phi\to K^0\bar{K}^0$ CP violation experiments.
[ { "created": "Mon, 5 Jul 1999 14:17:06 GMT", "version": "v1" }, { "created": "Sat, 29 Jan 2000 09:37:07 GMT", "version": "v2" }, { "created": "Thu, 24 Feb 2000 05:29:39 GMT", "version": "v3" } ]
2009-10-31
[ [ "Zhuang", "T. -L.", "" ], [ "Wang", "X. -J.", "" ], [ "Yan", "M. -L.", "" ] ]
In this paper, radiative decays $\rho^0 \to \pi^+\pi^-\gamma, \pi^0\pi^0\gamma$ ,$\phi \to K^+K^-\gamma, K^0 \bar{K^0}\gamma$ are studied systematically in the U(3)$_L\timesU(3)_R$ chiral theory of mesons. The theoretical differential spectrum with respect to photon energy and branch ratio for $\rho^0 \to \pi^+\pi^-\gamma$ agree well with the experimental data. Differential spectrums and branch ratios for $\rho^0 \to \pi^0\pi^0\gamma, \phi \to K^+ K^-\gamma,\phi \to K^0\bar{K^0}\gamma$ are predicted. The process $\phi \to K^0 \bar{K^0} \gamma$ is relevant to precision measurment of CP-violation parameters in the kaon systerm at a $\phi$-factory. We give a complete estimate of the branch ratio for this decay process by including scalar resonance $f_0, a_0$ poles, nonresonant smooth amplitude and an abnormal parity process with $K^*$ pole which hasn't been considered before. We conclude that processes with intermediate $K^*$ do not pose a potential background problem for $\phi\to K^0\bar{K}^0$ CP violation experiments.
1411.4557
Yonatan Kahn
Yonatan Kahn
Unbinned halo-independent methods for emerging dark matter signals
11 pages, 8 figures, to appear in the proceedings of the Interplay between Particle and Astroparticle Physics (IPA 2014) workshop, 18-22 August 2014, Queen Mary University of London
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Halo-independent methods for analyzing direct detection experiments can provide robust results while making no assumptions about the dark matter halo in our galaxy. We extend existing methods to the case of unbinned data, which is especially well suited to emerging dark matter signals with only a few events in a nearly background-free environment. We show that such methods can easily be generalized to the case of inelastic or exothermic scattering, and provide a useful handle on extracting results independent of the halo model while maximizing the available experimental information.
[ { "created": "Mon, 17 Nov 2014 17:21:58 GMT", "version": "v1" } ]
2014-11-18
[ [ "Kahn", "Yonatan", "" ] ]
Halo-independent methods for analyzing direct detection experiments can provide robust results while making no assumptions about the dark matter halo in our galaxy. We extend existing methods to the case of unbinned data, which is especially well suited to emerging dark matter signals with only a few events in a nearly background-free environment. We show that such methods can easily be generalized to the case of inelastic or exothermic scattering, and provide a useful handle on extracting results independent of the halo model while maximizing the available experimental information.
2110.12339
Jin Hu
Jin Hu
Relativistic kinetic equation for dense gases from quantum field theory
null
null
null
null
hep-ph
http://creativecommons.org/publicdomain/zero/1.0/
We derive the relativistic kinetic equation and collision kernel for dense gases of spin $0$ particles from quantum field theory based on the Wigner-function formalism. The formalism developed by Degroot can be used as an effective way for density expansion of the kinetic equation. The kinetic equation obtained in the lowest order in density recovers the Boltzmann equation with a nonlocal binary collision term. Keeping this expansion procedure, we derive the triple collision term, which can be seen as a relativistic extension of correspondent works on the transport research about dense gases in the non-relativistic cases. Considering the widespread practicability in different physical systems, the kinetic equation for dense gases we obtain shall be put into good use.
[ { "created": "Sun, 24 Oct 2021 03:10:19 GMT", "version": "v1" } ]
2021-10-26
[ [ "Hu", "Jin", "" ] ]
We derive the relativistic kinetic equation and collision kernel for dense gases of spin $0$ particles from quantum field theory based on the Wigner-function formalism. The formalism developed by Degroot can be used as an effective way for density expansion of the kinetic equation. The kinetic equation obtained in the lowest order in density recovers the Boltzmann equation with a nonlocal binary collision term. Keeping this expansion procedure, we derive the triple collision term, which can be seen as a relativistic extension of correspondent works on the transport research about dense gases in the non-relativistic cases. Considering the widespread practicability in different physical systems, the kinetic equation for dense gases we obtain shall be put into good use.
1508.06540
Marc Scott
Nick Evans, Peter Jones, Marc Scott
Soft Walls in Dynamic AdS/QCD and the Techni-dilaton
10 pages, 6 figures,
Phys. Rev. D 92, 106003 (2015)
10.1103/PhysRevD.92.106003
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dynamic AdS/QCD is a modification of AdS/QCD that includes the running of the anomalous dimension of the q-bar q quark bilinear and in which the generation of the constituent quark mass plays the role of an IR wall. The model allows one to move away smoothly from the controlled spectrum of the N=2 super Yang-Mills theory of the D3/probe-D7 system to more QCD-like theories with chiral symmetry breaking. We investigate soft wall behaviour in the model that gives Regge trajectories with M_{n,s}^2 ~ n,s. To achieve these behaviours requires the quark's constituent mass to fall peculiarly sharply in the IR so that meson physics is sensitive to RG scales well below the quark's on-shell mass. Including soft wall behaviour in models of walking gauge dynamics breaks the near conformal symmetry which is present above the quark on-shell mass which can generate a large mass for the techni-dilaton like state. We conclude that the meson spectrum is rather sensitive to the IR decoupling.
[ { "created": "Wed, 26 Aug 2015 15:50:09 GMT", "version": "v1" } ]
2015-11-25
[ [ "Evans", "Nick", "" ], [ "Jones", "Peter", "" ], [ "Scott", "Marc", "" ] ]
Dynamic AdS/QCD is a modification of AdS/QCD that includes the running of the anomalous dimension of the q-bar q quark bilinear and in which the generation of the constituent quark mass plays the role of an IR wall. The model allows one to move away smoothly from the controlled spectrum of the N=2 super Yang-Mills theory of the D3/probe-D7 system to more QCD-like theories with chiral symmetry breaking. We investigate soft wall behaviour in the model that gives Regge trajectories with M_{n,s}^2 ~ n,s. To achieve these behaviours requires the quark's constituent mass to fall peculiarly sharply in the IR so that meson physics is sensitive to RG scales well below the quark's on-shell mass. Including soft wall behaviour in models of walking gauge dynamics breaks the near conformal symmetry which is present above the quark on-shell mass which can generate a large mass for the techni-dilaton like state. We conclude that the meson spectrum is rather sensitive to the IR decoupling.
2101.01921
Teruyuki Kitabayashi
Teruyuki Kitabayashi
Primordial black holes and scotogenic dark matter
29 pages, 10 figures
International Journal of Modern Physics A, Vol. 36, No. 18, 2150139 (2021)
10.1142/S0217751X21501396
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study the effect of the scotogenic dark matter on the primordial black holes (PBHs) and vice versa. We show that if the PBHs evaporate in the radiation dominant era, the upper limit of the initial mass of the PBHs $M_{\rm in}$ should be constrained as $10^4 \lesssim M_{\rm in}/M_{\rm Pl} \lesssim 10^{10}$ for $\mathcal{O}$(1) TeV scotogenic dark matter ($\mathcal{O}$(1) TeV is the most appropriate energy scale in the scotogenic model). On the other hand, if the PBHs evaporate in the PBH dominated era, a quite heavy scotogenic dark matter ($m_{/rm DM} /gtrsim 10^9$ GeV) for $M_{/rm in}/M_{/rm Pl} /sim 10^{13}$ may be allowed.
[ { "created": "Wed, 6 Jan 2021 08:39:50 GMT", "version": "v1" }, { "created": "Thu, 7 Jan 2021 02:31:00 GMT", "version": "v2" }, { "created": "Sun, 18 Apr 2021 05:35:19 GMT", "version": "v3" }, { "created": "Tue, 13 Jul 2021 01:28:02 GMT", "version": "v4" }, { "created": "Wed, 28 Jul 2021 04:48:04 GMT", "version": "v5" } ]
2021-07-29
[ [ "Kitabayashi", "Teruyuki", "" ] ]
We study the effect of the scotogenic dark matter on the primordial black holes (PBHs) and vice versa. We show that if the PBHs evaporate in the radiation dominant era, the upper limit of the initial mass of the PBHs $M_{\rm in}$ should be constrained as $10^4 \lesssim M_{\rm in}/M_{\rm Pl} \lesssim 10^{10}$ for $\mathcal{O}$(1) TeV scotogenic dark matter ($\mathcal{O}$(1) TeV is the most appropriate energy scale in the scotogenic model). On the other hand, if the PBHs evaporate in the PBH dominated era, a quite heavy scotogenic dark matter ($m_{/rm DM} /gtrsim 10^9$ GeV) for $M_{/rm in}/M_{/rm Pl} /sim 10^{13}$ may be allowed.
1207.0493
Spencer Chang
Spencer Chang, Christopher A. Newby, Nirmal Raj, Chaowaroj Wanotayaroj
Revisiting Theories with Enhanced Higgs Couplings to Weak Gauge Bosons
9 pages, 9 figures, revtex4; v2, references added
Phys.Rev. D86 (2012) 095015
10.1103/PhysRevD.86.095015
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Based on recent LHC Higgs analyses and in anticipation of future results we revisit theories where Higgs bosons can couple to weak gauge bosons with enhanced strength relative to the Standard Model value. Specifically, we look at the Georgi-Machacek model and its generalizations where higher "spin" representations of SU(2)_L break electroweak symmetry while maintaining custodial SU(2). In these theories, there is not only a Higgs-like boson but partner Higgs scalars transforming under representations of custodial SU(2), leading to a rich phenomenology. These theories serve as a consistent theoretical and experimental framework to explain enhanced couplings to gauge bosons, including fermiophobic Higgses. We focus on the phenomenology of a neutral scalar partner to the Higgs, which is determined once the Higgs couplings are specified. Depending on the parameter space, this partner could have i) enhanced fermion and gauge boson couplings and should be searched for at high mass (> 600 GeV), ii) have suppressed couplings and could be searched for at lower masses, where the Standard Model Higgs has already been ruled out, and iii) have fermiophilic couplings, where it can be searched for in heavy Higgs and top resonance searches. In the first two regions, the partner also has substantial decay rates into a pair of Higgs bosons. We touch briefly on the more model-dependent effects of the nontrivial SU(2)_C multiplets, which have exotic signals, such as a doubly-charged Higgs. We also discuss how the loop induced effects of these scalars tend to reduce the Higgs decay rate to photons, adding an additional uncertainty when extracting the couplings for the Higgs boson.
[ { "created": "Mon, 2 Jul 2012 20:00:00 GMT", "version": "v1" }, { "created": "Fri, 27 Jul 2012 00:08:07 GMT", "version": "v2" } ]
2013-03-11
[ [ "Chang", "Spencer", "" ], [ "Newby", "Christopher A.", "" ], [ "Raj", "Nirmal", "" ], [ "Wanotayaroj", "Chaowaroj", "" ] ]
Based on recent LHC Higgs analyses and in anticipation of future results we revisit theories where Higgs bosons can couple to weak gauge bosons with enhanced strength relative to the Standard Model value. Specifically, we look at the Georgi-Machacek model and its generalizations where higher "spin" representations of SU(2)_L break electroweak symmetry while maintaining custodial SU(2). In these theories, there is not only a Higgs-like boson but partner Higgs scalars transforming under representations of custodial SU(2), leading to a rich phenomenology. These theories serve as a consistent theoretical and experimental framework to explain enhanced couplings to gauge bosons, including fermiophobic Higgses. We focus on the phenomenology of a neutral scalar partner to the Higgs, which is determined once the Higgs couplings are specified. Depending on the parameter space, this partner could have i) enhanced fermion and gauge boson couplings and should be searched for at high mass (> 600 GeV), ii) have suppressed couplings and could be searched for at lower masses, where the Standard Model Higgs has already been ruled out, and iii) have fermiophilic couplings, where it can be searched for in heavy Higgs and top resonance searches. In the first two regions, the partner also has substantial decay rates into a pair of Higgs bosons. We touch briefly on the more model-dependent effects of the nontrivial SU(2)_C multiplets, which have exotic signals, such as a doubly-charged Higgs. We also discuss how the loop induced effects of these scalars tend to reduce the Higgs decay rate to photons, adding an additional uncertainty when extracting the couplings for the Higgs boson.
1407.7203
Sarbani Majumder
Sanjay K. Ghosh (1), Anirban Lahiri (2), Sarbani Majumder (3), Munshi G. Mustafa (3), Sibaji Raha (1), Rajarshi Ray (1) ((1) Bose Institute, Kolkata, India. (2) Tata Institute of Fundamental Research, Mumbai, India. (3) Saha Institute of Nuclear Physics, Kolkata, India.)
Quark Number Susceptibility : Revisited with Fluctuation-Dissipation Theorem in mean field theories
null
Phys. Rev. D 90, 054030 (2014)
10.1103/PhysRevD.90.054030
TIFR/TH/14-21 ; SINP/TNP/2014/05
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Fluctuations of conserved quantum numbers are associated with the corresponding susceptibilities because of the symmetry of the system. The underlying fact is that these fluctuations as defined through the static correlators become identical to the direct calculation of these susceptibilities defined through the thermodynamic derivatives, due to the fluctuation-dissipation theorem. Through a rigorous exercise we explicitly show that a diagrammatic calculation of the static correlators associated with the conserved quark number fluctuations and the corresponding susceptibilities are possible in case of mean field theories, if the implicit dependence of the mean fields on the quark chemical potential are taken into account appropriately. As an aside we also give an analytical prescription for obtaining the implicit dependence of the mean fields on the quark chemical potential.
[ { "created": "Sun, 27 Jul 2014 09:35:46 GMT", "version": "v1" }, { "created": "Sat, 4 Oct 2014 04:35:48 GMT", "version": "v2" } ]
2014-10-07
[ [ "Ghosh", "Sanjay K.", "" ], [ "Lahiri", "Anirban", "" ], [ "Majumder", "Sarbani", "" ], [ "Mustafa", "Munshi G.", "" ], [ "Raha", "Sibaji", "" ], [ "Ray", "Rajarshi", "" ] ]
Fluctuations of conserved quantum numbers are associated with the corresponding susceptibilities because of the symmetry of the system. The underlying fact is that these fluctuations as defined through the static correlators become identical to the direct calculation of these susceptibilities defined through the thermodynamic derivatives, due to the fluctuation-dissipation theorem. Through a rigorous exercise we explicitly show that a diagrammatic calculation of the static correlators associated with the conserved quark number fluctuations and the corresponding susceptibilities are possible in case of mean field theories, if the implicit dependence of the mean fields on the quark chemical potential are taken into account appropriately. As an aside we also give an analytical prescription for obtaining the implicit dependence of the mean fields on the quark chemical potential.
hep-ph/9904347
Marcos Donizeti Rodrigues Sampaio
O.A.Battistel, G.Dallabona, M.C.Nemes (UFMG-Brazil) and B.Hiller (University of Coimbra-Portugal)
Anomalous pion decay revisited
7 pages, LaTeX, no figures
null
null
null
hep-ph
null
An implicit four dimensional regularization is applied to calculate the axial-vector-vector anomalous amplitude. The present technique always complies with results of Dimensional Regularization and can be easily applied to processes involving odd numbers of $\gamma_5$ matrices. This is illustrated explicitely in the example of this letter.
[ { "created": "Thu, 15 Apr 1999 15:00:19 GMT", "version": "v1" } ]
2007-05-23
[ [ "Battistel", "O. A.", "", "UFMG-Brazil" ], [ "Dallabona", "G.", "", "UFMG-Brazil" ], [ "Nemes", "M. C.", "", "UFMG-Brazil" ], [ "Hiller", "B.", "", "University of Coimbra-Portugal" ] ]
An implicit four dimensional regularization is applied to calculate the axial-vector-vector anomalous amplitude. The present technique always complies with results of Dimensional Regularization and can be easily applied to processes involving odd numbers of $\gamma_5$ matrices. This is illustrated explicitely in the example of this letter.
2407.09593
Ben Stefanek
Ben A. Stefanek
Non-universal probes of composite Higgs models: New bounds and prospects for FCC-ee
References and discussion of FCC theory uncertainties added. Version submitted for publication
null
null
KCL-PH-TH/2024-43
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the leading loop-level phenomenology of composite Higgs models via the effective field theory of a strongly interacting light Higgs and top quark (SILH+TQ). We systematically analyze the renormalization group evolution (RGE) of tree-generated operators in the SILH+TQ scenario, finding large mixings of flavor non-universal operators into those affecting electroweak precision observables. We show that these model-independent RG contributions are more important than typical estimates for finite parts. Flavor non-universal effects are completely captured by examining three options for the top mixing: fully composite $q_L^3$, equal compositeness, and fully composite $t_R$. In the most phenomenologically viable case of a fully composite $t_R$, we show that the strongest bound on the natural parameter space comes from next-to-leading log running of the 4-top operator $O_{tt} = (\bar t_R \gamma_\mu t_R)(\bar t_R \gamma^\mu t_R)$ into the Peskin-Takeuchi $T$ parameter. In general, we find that this 2-loop effect allows existing electroweak precision data to give a better constraint on 4-top operators compared to high-energy probes from top production at the LHC. Independent of the top mixing, we find that a future tera-$Z$ machine such as FCC-ee has the potential to probe composite Higgs models up to a scale of $m_* \gtrsim 25$ TeV, and test the naturalness of the electroweak scale at the $\lesssim 10^{-4}$ level.
[ { "created": "Fri, 12 Jul 2024 18:00:00 GMT", "version": "v1" }, { "created": "Mon, 22 Jul 2024 16:14:29 GMT", "version": "v2" } ]
2024-07-23
[ [ "Stefanek", "Ben A.", "" ] ]
We study the leading loop-level phenomenology of composite Higgs models via the effective field theory of a strongly interacting light Higgs and top quark (SILH+TQ). We systematically analyze the renormalization group evolution (RGE) of tree-generated operators in the SILH+TQ scenario, finding large mixings of flavor non-universal operators into those affecting electroweak precision observables. We show that these model-independent RG contributions are more important than typical estimates for finite parts. Flavor non-universal effects are completely captured by examining three options for the top mixing: fully composite $q_L^3$, equal compositeness, and fully composite $t_R$. In the most phenomenologically viable case of a fully composite $t_R$, we show that the strongest bound on the natural parameter space comes from next-to-leading log running of the 4-top operator $O_{tt} = (\bar t_R \gamma_\mu t_R)(\bar t_R \gamma^\mu t_R)$ into the Peskin-Takeuchi $T$ parameter. In general, we find that this 2-loop effect allows existing electroweak precision data to give a better constraint on 4-top operators compared to high-energy probes from top production at the LHC. Independent of the top mixing, we find that a future tera-$Z$ machine such as FCC-ee has the potential to probe composite Higgs models up to a scale of $m_* \gtrsim 25$ TeV, and test the naturalness of the electroweak scale at the $\lesssim 10^{-4}$ level.
2309.13106
Yu-Dai Tsai
Yu-Dai Tsai, Davide Farnocchia, Marco Micheli, Sunny Vagnozzi, Luca Visinelli
Constraints on fifth forces and ultralight dark matter from OSIRIS-REx target asteroid Bennu
1 figure, 7 pages plus references
Communications Physics - Nature (2024)
null
UCI-HEP-TR-2023-04; FERMILAB-PUB-23-538-T-V; CA21106; CA21136
hep-ph astro-ph.CO gr-qc hep-ex hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using the OSIRIS-REx mission and ground-based tracking data for the asteroid Bennu, we derive new constraints on fifth forces and ultralight dark matter. The bounds we obtain are strongest for mediator masses $m \sim 10^{-18} - 10^{-17}\,{\rm eV}$, where we currently achieve the tightest bounds. Our limits can be translated to a wide class of models leading to Yukawa-type fifth forces, and we demonstrate how they apply to $U(1)_B$ dark photons and baryon-coupled scalars. Our results demonstrate the potential of asteroid tracking in probing well-motivated extensions of the Standard Model and ultralight dark matter satisfying the fuzzy dark matter constraints.
[ { "created": "Fri, 22 Sep 2023 18:00:00 GMT", "version": "v1" } ]
2024-08-15
[ [ "Tsai", "Yu-Dai", "" ], [ "Farnocchia", "Davide", "" ], [ "Micheli", "Marco", "" ], [ "Vagnozzi", "Sunny", "" ], [ "Visinelli", "Luca", "" ] ]
Using the OSIRIS-REx mission and ground-based tracking data for the asteroid Bennu, we derive new constraints on fifth forces and ultralight dark matter. The bounds we obtain are strongest for mediator masses $m \sim 10^{-18} - 10^{-17}\,{\rm eV}$, where we currently achieve the tightest bounds. Our limits can be translated to a wide class of models leading to Yukawa-type fifth forces, and we demonstrate how they apply to $U(1)_B$ dark photons and baryon-coupled scalars. Our results demonstrate the potential of asteroid tracking in probing well-motivated extensions of the Standard Model and ultralight dark matter satisfying the fuzzy dark matter constraints.
0908.3116
Alfonso Zerwekh
Alfonso R. Zerwekh
Axigluon Couplings in the Presence of Extra Color-Octet Spin-One Fields
null
Eur.Phys.J.C65:543-546,2010
10.1140/epjc/s10052-009-1201-1
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we study how the interaction of the axigluon with quarks is modified when we introduce new color-octet spin-one fields in a chiral color model. We show that in this case the strength of this interaction is not completely determined by the gauge symmetry any more and can be significantly weaker than the one predicted in the original chiral color model. In this way, we reinterpret the non-observability of the axigluon at the Tevatron, not as a limit on the axigluon mass, but as a limit on the strength of the axigluon coupling to quarks.
[ { "created": "Fri, 21 Aug 2009 12:46:51 GMT", "version": "v1" } ]
2010-02-11
[ [ "Zerwekh", "Alfonso R.", "" ] ]
In this paper, we study how the interaction of the axigluon with quarks is modified when we introduce new color-octet spin-one fields in a chiral color model. We show that in this case the strength of this interaction is not completely determined by the gauge symmetry any more and can be significantly weaker than the one predicted in the original chiral color model. In this way, we reinterpret the non-observability of the axigluon at the Tevatron, not as a limit on the axigluon mass, but as a limit on the strength of the axigluon coupling to quarks.
hep-ph/0008037
Thomas G. Rizzo
Thomas G. Rizzo
New Physics Beyond the Standard Model at $\gamma \gamma$ Colliders
8 pages, 6 figs, LaTex, Talk Given at the International Workshop on High Energy Photon Colliders, DESY Hamburg, June 14-17, 2000
Nucl.Instrum.Meth. A472 (2001) 37-42
10.1016/S0168-9002(01)01160-3
SLAC-PUB-8544
hep-ph
null
The complementarity of $e^+e^-$ and $\gamma \gamma$ colliders to discover and explore new physics beyond the Standard Model(SM) is discussed. After briefly surveying a number of various new physics scenarios we concentrate in detail on signatures for Large Extra Dimensions via the process $\gamma \gamma \to WW$.
[ { "created": "Thu, 3 Aug 2000 22:01:12 GMT", "version": "v1" } ]
2009-10-31
[ [ "Rizzo", "Thomas G.", "" ] ]
The complementarity of $e^+e^-$ and $\gamma \gamma$ colliders to discover and explore new physics beyond the Standard Model(SM) is discussed. After briefly surveying a number of various new physics scenarios we concentrate in detail on signatures for Large Extra Dimensions via the process $\gamma \gamma \to WW$.
1602.06363
Archil Kobakhidze
Archil Kobakhidze
Solving the Strong CP Problem with High-Colour Quarks and Composite Axion
10 pages
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I propose a new axionic solution to the strong CP problem which involves a hypothetical vector-like quark(s) in a high-colour representation of the conventional QCD. There are two distinct scenarios. If the current mass of the exotic quark is zero, the strong CP phase can be trivially rotated away. The high-colour quark is `hidden' in various bounds states, the lightest being the composite axion field, with properties similar to the standard invisible axion. If the high-colour quark acquire a non-zero current mass due to the spontaneous chiral symmetry breaking, the composite axion can be heavy, while the strong CP phase is still cancelling out in the vacuum. The phenomenology and cosmological implications of the heavy composite axion differs drastically from the standard invisible axion.
[ { "created": "Sat, 20 Feb 2016 04:33:42 GMT", "version": "v1" } ]
2016-02-23
[ [ "Kobakhidze", "Archil", "" ] ]
I propose a new axionic solution to the strong CP problem which involves a hypothetical vector-like quark(s) in a high-colour representation of the conventional QCD. There are two distinct scenarios. If the current mass of the exotic quark is zero, the strong CP phase can be trivially rotated away. The high-colour quark is `hidden' in various bounds states, the lightest being the composite axion field, with properties similar to the standard invisible axion. If the high-colour quark acquire a non-zero current mass due to the spontaneous chiral symmetry breaking, the composite axion can be heavy, while the strong CP phase is still cancelling out in the vacuum. The phenomenology and cosmological implications of the heavy composite axion differs drastically from the standard invisible axion.
2402.12228
Selym Villalba-Chavez Dr.
A. Eckey, A. Golub, F. C. Salgado, S. Villalba-Ch\'avez, A. B. Voitkiv, M. Zepf, C. M\"uller
Impact of laser focussing and radiation reaction on particle spectra from nonlinear Breit-Wheeler pair production in the nonperturbative regime
11 pages, 7 figures
null
null
null
hep-ph physics.atom-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Near-future experiments intend to detect strong-field Breit-Wheeler pair creation from the collision between bremsstrahlung bursts containing GeV-$\gamma$ quanta and high-intensity laser pulses. In this theoretical study, we investigate the influence of laser focusing, radiation reaction and a broad bremsstrahlung $\gamma$ spectrum on the energy and angular distributions of created pairs. Understanding the role of these inherent reaction attributes provides relevant insights for experimental detection strategies and data interpretation. We show that the inclusion of radiation reaction leads to a narrow energy spectrum of the yielded particles, whose maximum is shifted to substantially lower energies as compared to the case in which radiative energy losses are ignored. The broad bremsstrahlung spectrum also has distinct influence on the particle distributions, whereas the impact of laser focusing turns out to be rather moderate in the considered parameter regime.
[ { "created": "Mon, 19 Feb 2024 15:35:01 GMT", "version": "v1" } ]
2024-02-20
[ [ "Eckey", "A.", "" ], [ "Golub", "A.", "" ], [ "Salgado", "F. C.", "" ], [ "Villalba-Chávez", "S.", "" ], [ "Voitkiv", "A. B.", "" ], [ "Zepf", "M.", "" ], [ "Müller", "C.", "" ] ]
Near-future experiments intend to detect strong-field Breit-Wheeler pair creation from the collision between bremsstrahlung bursts containing GeV-$\gamma$ quanta and high-intensity laser pulses. In this theoretical study, we investigate the influence of laser focusing, radiation reaction and a broad bremsstrahlung $\gamma$ spectrum on the energy and angular distributions of created pairs. Understanding the role of these inherent reaction attributes provides relevant insights for experimental detection strategies and data interpretation. We show that the inclusion of radiation reaction leads to a narrow energy spectrum of the yielded particles, whose maximum is shifted to substantially lower energies as compared to the case in which radiative energy losses are ignored. The broad bremsstrahlung spectrum also has distinct influence on the particle distributions, whereas the impact of laser focusing turns out to be rather moderate in the considered parameter regime.
0911.0252
Roman Nikolaevich Lee
R.N. Lee
Space-time dimensionality D as complex variable: calculating loop integrals using dimensional recurrence relation and analytical properties with respect to D
Several misprints corrected
Nucl.Phys.B830:474-492,2010
10.1016/j.nuclphysb.2009.12.025
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that dimensional recurrence relation and analytical properties of the loop integrals as functions of complex variable $\mathcal{D}$ (space-time dimensionality) provide a regular way to derive analytical representations of loop integrals. The representations derived have a form of exponentially converging sums. Several examples of the developed technique are given.
[ { "created": "Mon, 2 Nov 2009 08:02:11 GMT", "version": "v1" }, { "created": "Wed, 18 Nov 2009 12:17:14 GMT", "version": "v2" } ]
2010-02-19
[ [ "Lee", "R. N.", "" ] ]
We show that dimensional recurrence relation and analytical properties of the loop integrals as functions of complex variable $\mathcal{D}$ (space-time dimensionality) provide a regular way to derive analytical representations of loop integrals. The representations derived have a form of exponentially converging sums. Several examples of the developed technique are given.
2209.06793
Kousik Loho
Baradhwaj Coleppa, Kousik Loho, Sujay Shil
Dark Sector extensions of the Littlest Seesaw in the presence of Primordial Black Holes
14 pages, 8 figures, accepted in JCAP
null
10.1088/1475-7516/2023/06/027
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The Littlest Seesaw model is a very well motivated dark matter model. Here we consider an extension of that model with an additional scalar and an additional fermionic particle under the freeze-in scenario. Formation of black hole of a certain mass range at primordial times can act as an alternate production mechanism for the dark matter particles as it evaporates via Hawking radiation. Furthermore, the presence of primordial black holes with substantial energy density gives rise to non-standard cosmology which also modifies the freeze-in production. In this paper, we have investigated the extended Littlest Seesaw model under the freeze-in scenario in the presence of a primordial black hole for various interesting cases and constrained the parameter space accordingly. If the universe is primordial black hole dominated at any point in the evolution of the universe, we find that the final relic in that case is dominated mostly by the evaporation component for a high dark matter mass and by the freeze-in component for a low dark matter mass.
[ { "created": "Wed, 14 Sep 2022 17:22:05 GMT", "version": "v1" }, { "created": "Tue, 30 May 2023 07:48:53 GMT", "version": "v2" } ]
2023-06-28
[ [ "Coleppa", "Baradhwaj", "" ], [ "Loho", "Kousik", "" ], [ "Shil", "Sujay", "" ] ]
The Littlest Seesaw model is a very well motivated dark matter model. Here we consider an extension of that model with an additional scalar and an additional fermionic particle under the freeze-in scenario. Formation of black hole of a certain mass range at primordial times can act as an alternate production mechanism for the dark matter particles as it evaporates via Hawking radiation. Furthermore, the presence of primordial black holes with substantial energy density gives rise to non-standard cosmology which also modifies the freeze-in production. In this paper, we have investigated the extended Littlest Seesaw model under the freeze-in scenario in the presence of a primordial black hole for various interesting cases and constrained the parameter space accordingly. If the universe is primordial black hole dominated at any point in the evolution of the universe, we find that the final relic in that case is dominated mostly by the evaporation component for a high dark matter mass and by the freeze-in component for a low dark matter mass.
hep-ph/9807209
Takashi Nasuno
Jiro Kodaira (Hiroshima Univ.), Takashi Nasuno (Hiroshima Univ.), Stephen Parke (Fermi National Accelerator Laboratory)
QCD Corrections to Spin Correlations in Top Quark Production at Lepton Colliders
32 pages, REVTeX, 13 Postscript figures, psfig.sty and here.sty are required. Several references added, Tables 3, 4 and 5 are changed
Phys.Rev.D59:014023,1998
10.1103/PhysRevD.59.014023
null
hep-ph
null
Spin correlations, using a generic spin basis, are investigated to leading order in QCD for top quark production at lepton colliders. Even though, these radiative corrections induce an anomalous gamma/Z magnetic moment for the top quarks and allow for single, real gluon emission, their effects on the top quark spin orientation are very small. The final results are that the top (or anti-top) quarks are produced in an essentially unique spin configuration in polarized lepton collisions even after including the O(alpha_{s}) QCD corrections.
[ { "created": "Wed, 1 Jul 1998 13:42:48 GMT", "version": "v1" }, { "created": "Thu, 8 Oct 1998 03:18:30 GMT", "version": "v2" } ]
2010-02-03
[ [ "Kodaira", "Jiro", "", "Hiroshima Univ." ], [ "Nasuno", "Takashi", "", "Hiroshima Univ." ], [ "Parke", "Stephen", "", "Fermi National Accelerator Laboratory" ] ]
Spin correlations, using a generic spin basis, are investigated to leading order in QCD for top quark production at lepton colliders. Even though, these radiative corrections induce an anomalous gamma/Z magnetic moment for the top quarks and allow for single, real gluon emission, their effects on the top quark spin orientation are very small. The final results are that the top (or anti-top) quarks are produced in an essentially unique spin configuration in polarized lepton collisions even after including the O(alpha_{s}) QCD corrections.
1107.4467
Shigeru Odaka
Shigeru Odaka, Yoshimasa Kurihara
GR@PPA 2.8: initial-state jet matching for weak boson production processes at hadron collisions
29 pages, 14 figures; minor changes to clarify the discussions, and corrections of typos
null
10.1016/j.cpc.2011.12.023
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The initial-state jet matching method introduced in our previous studies has been applied to the event generation of single $W$ and $Z$ production processes and diboson ($W^{+}W^{-}$, $WZ$ and $ZZ$) production processes at hadron collisions in the framework of the GR@PPA event generator. The generated events reproduce the transverse momentum spectra of weak bosons continuously in the entire kinematical region. The matrix elements (ME) for hard interactions are still at the tree level. As in previous versions, the decays of weak bosons are included in the matrix elements. Therefore, spin correlations and phase-space effects in the decay of weak bosons are exact at the tree level. The program package includes custom-made parton shower programs as well as ME-based hard interaction generators in order to achieve self-consistent jet matching. The generated events can be passed to general-purpose event generators to make the simulation proceed down to the hadron level.
[ { "created": "Fri, 22 Jul 2011 09:53:52 GMT", "version": "v1" }, { "created": "Wed, 18 Jan 2012 05:52:05 GMT", "version": "v2" } ]
2015-05-28
[ [ "Odaka", "Shigeru", "" ], [ "Kurihara", "Yoshimasa", "" ] ]
The initial-state jet matching method introduced in our previous studies has been applied to the event generation of single $W$ and $Z$ production processes and diboson ($W^{+}W^{-}$, $WZ$ and $ZZ$) production processes at hadron collisions in the framework of the GR@PPA event generator. The generated events reproduce the transverse momentum spectra of weak bosons continuously in the entire kinematical region. The matrix elements (ME) for hard interactions are still at the tree level. As in previous versions, the decays of weak bosons are included in the matrix elements. Therefore, spin correlations and phase-space effects in the decay of weak bosons are exact at the tree level. The program package includes custom-made parton shower programs as well as ME-based hard interaction generators in order to achieve self-consistent jet matching. The generated events can be passed to general-purpose event generators to make the simulation proceed down to the hadron level.
hep-ph/0211284
Jeremie Vinet
James M. Cline and J\'er\'emie Vinet
Problems with Time-Varying Extra Dimensions or "Cardassian Expansion" as Alternatives to Dark Energy
8 pages, minor changes. To appear in Physical Review D
Phys.Rev. D68 (2003) 025015
10.1103/PhysRevD.68.025015
McGill-02-38, CERN-2002-340
hep-ph astro-ph hep-th
null
It has recently been proposed that the Universe might be accelerating as a consequence of extra dimensions with time varying size. We show that although these scenarios can lead to acceleration, they run into serious difficulty when taking into account limits on the time variation of the four dimensional Newton's constant. On the other hand, models of ``Cardassian'' expansion based on extra dimensions which have been constructed so far violate the weak energy condition for the bulk stress energy, for parameters that give an accelerating universe.
[ { "created": "Mon, 18 Nov 2002 20:26:45 GMT", "version": "v1" }, { "created": "Thu, 21 Nov 2002 18:31:23 GMT", "version": "v2" }, { "created": "Thu, 29 May 2003 12:14:30 GMT", "version": "v3" } ]
2009-11-07
[ [ "Cline", "James M.", "" ], [ "Vinet", "Jérémie", "" ] ]
It has recently been proposed that the Universe might be accelerating as a consequence of extra dimensions with time varying size. We show that although these scenarios can lead to acceleration, they run into serious difficulty when taking into account limits on the time variation of the four dimensional Newton's constant. On the other hand, models of ``Cardassian'' expansion based on extra dimensions which have been constructed so far violate the weak energy condition for the bulk stress energy, for parameters that give an accelerating universe.
1210.8435
D. V. Ahluwalia
D. V. Ahluwalia, Cheng-Yang Lee
Gamma-ray bursts and the relevance of rotation-induced neutrino sterilization
4 pages
Phys. Lett. B 719 (2013) 218-219
10.1016/j.physletb.2013.01.053
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A la Pontecorvo when one defines electroweak flavour states of neutrinos as a linear superposition of mass eigenstates one ignores the associated spin. If, however, there is a significant rotation between the neutrino source, and the detector, a negative helicity state emitted by the former acquires a non-zero probability amplitude to be perceived as a positive helicity state by the latter. Both of these states are still in the left-Weyl sector of the Lorentz group. The electroweak interaction cross sections for such helicity-flipped states are suppressed by a factor of $(m_\nu/E_\nu)^2$, where $m_\nu$ is the expectation value of the neutrino mass, and $E_\nu$ is the associated energy. Thus, if the detecting process is based on electroweak interactions, and the neutrino source is a highly rotating object, the rotation-induced helicity flip becomes very significant in interpreting the data. The effect immediately generalizes to anti-neutrinos. Motivated by these observations we present a generalization of the Pontecorvo formalism and discuss its relevance in the context of recent data obtained by the IceCube neutrino telescope.
[ { "created": "Wed, 31 Oct 2012 18:51:38 GMT", "version": "v1" } ]
2013-02-21
[ [ "Ahluwalia", "D. V.", "" ], [ "Lee", "Cheng-Yang", "" ] ]
A la Pontecorvo when one defines electroweak flavour states of neutrinos as a linear superposition of mass eigenstates one ignores the associated spin. If, however, there is a significant rotation between the neutrino source, and the detector, a negative helicity state emitted by the former acquires a non-zero probability amplitude to be perceived as a positive helicity state by the latter. Both of these states are still in the left-Weyl sector of the Lorentz group. The electroweak interaction cross sections for such helicity-flipped states are suppressed by a factor of $(m_\nu/E_\nu)^2$, where $m_\nu$ is the expectation value of the neutrino mass, and $E_\nu$ is the associated energy. Thus, if the detecting process is based on electroweak interactions, and the neutrino source is a highly rotating object, the rotation-induced helicity flip becomes very significant in interpreting the data. The effect immediately generalizes to anti-neutrinos. Motivated by these observations we present a generalization of the Pontecorvo formalism and discuss its relevance in the context of recent data obtained by the IceCube neutrino telescope.
1201.3834
Philip Rau
P. Rau, J. Steinheimer, S. Schramm, H. St\"ocker
Resonance States in an Effective Chiral Hadronic Model
Talk given at the international conference on Critical Point and Onset of Deconfinement 2011 in Wuhan, PR China
Central European Journal of Physics, Volume 10, Issue 6 (2012), 1302-1305
10.2478/s11534-012-0039-6
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With an effective chiral flavour SU(3) model we show the effect of hadronic resonances on the QCD phase diagram. We state that varying the resonance couplings to the scalar and vector fields affects the order and location of the phase transition, the possible existence of a critical end point (CEP), and the thermodynamic properties. We present (strange) quark number susceptibilities at zero baryochemical potential and at three different points at the phase transition. Comparing results to lattice QCD, we state that reasonable large vector couplings limit the phase transition to a smooth crossover ruling out a CEP.
[ { "created": "Wed, 18 Jan 2012 16:13:02 GMT", "version": "v1" } ]
2012-12-07
[ [ "Rau", "P.", "" ], [ "Steinheimer", "J.", "" ], [ "Schramm", "S.", "" ], [ "Stöcker", "H.", "" ] ]
With an effective chiral flavour SU(3) model we show the effect of hadronic resonances on the QCD phase diagram. We state that varying the resonance couplings to the scalar and vector fields affects the order and location of the phase transition, the possible existence of a critical end point (CEP), and the thermodynamic properties. We present (strange) quark number susceptibilities at zero baryochemical potential and at three different points at the phase transition. Comparing results to lattice QCD, we state that reasonable large vector couplings limit the phase transition to a smooth crossover ruling out a CEP.
2406.10969
Jingwei Lian
Jingwei Lian
The 95GeV Excesses in the $\mathbb{Z}_3$-symmetric Next-to Minimal Supersymmetric Standard Model
30 pages, 6 figures,
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Recent analyses by CMS and ATLAS suggest a deviation in the di-photon channel at approximately 95 GeV, alongside a previously observed excess in $b\bar{b}$ signals at a similar mass by LEP, potentially hinting at a new scalar particle. This study explores this possibility within the framework of the well-established $\mathbb{Z}_3$-symmetric Next-to-Minimal Supersymmetric Standard Model. A comprehensive parameter scan was conducted, integrating constraints from dark matter relic density, direct detection experiments, and the properties of the observed 125 GeV Higgs boson. The results demonstrate that the model can accommodate the observed excesses with a singlet-dominated CP-even Higgs boson near 95 GeV. The model accurately predicts signal strengths of the di-photon and $b\bar{b}$ channels at a level of $1\sigma$. Furthermore, it accounts for the measured dark matter relic abundance through Bino-dominated neutralinos co-annihilation with Wino-like electroweakinos, all while remaining consistent with existing LHC constraints. These findings pave the way for future validation at the high-luminosity LHC and linear colliders, which may offer crucial tests of the model's predictions.
[ { "created": "Sun, 16 Jun 2024 15:02:13 GMT", "version": "v1" } ]
2024-06-18
[ [ "Lian", "Jingwei", "" ] ]
Recent analyses by CMS and ATLAS suggest a deviation in the di-photon channel at approximately 95 GeV, alongside a previously observed excess in $b\bar{b}$ signals at a similar mass by LEP, potentially hinting at a new scalar particle. This study explores this possibility within the framework of the well-established $\mathbb{Z}_3$-symmetric Next-to-Minimal Supersymmetric Standard Model. A comprehensive parameter scan was conducted, integrating constraints from dark matter relic density, direct detection experiments, and the properties of the observed 125 GeV Higgs boson. The results demonstrate that the model can accommodate the observed excesses with a singlet-dominated CP-even Higgs boson near 95 GeV. The model accurately predicts signal strengths of the di-photon and $b\bar{b}$ channels at a level of $1\sigma$. Furthermore, it accounts for the measured dark matter relic abundance through Bino-dominated neutralinos co-annihilation with Wino-like electroweakinos, all while remaining consistent with existing LHC constraints. These findings pave the way for future validation at the high-luminosity LHC and linear colliders, which may offer crucial tests of the model's predictions.
hep-ph/9803288
Jan Kwiecinski
J. Kwiecinski
Spin Dependent Structure Function $g_1$ at Low $x$
Talk given at the Cracow Epiphany Conference on Spin Effects in Particle Physics, 9-11 January 1998, Cracow, Poland
Acta Phys.Polon.B29:1201-1216,1998
null
null
hep-ph
null
Theoretical expectations concerning small $x$ behaviour of the spin dependent structure function $g_1$ are summarised. This includes discussion of the Regge pole model predictions and of the double $ln^2(1/x)$ effects implied by perturbative QCD. The quantitative implementation of the latter is described within the unified scheme incorporating both Altarelli-Parisi evolution and the double $ln^2(1/x)$ resummation. The double $ln^2(1/x)$ effects are found to be important in the region of $x$ which can possibly be probed at HERA. Predictions for the polarized gluon distribution $\Delta G(x,Q^2)$ at low $x$ are also given.
[ { "created": "Mon, 9 Mar 1998 15:54:26 GMT", "version": "v1" } ]
2014-11-17
[ [ "Kwiecinski", "J.", "" ] ]
Theoretical expectations concerning small $x$ behaviour of the spin dependent structure function $g_1$ are summarised. This includes discussion of the Regge pole model predictions and of the double $ln^2(1/x)$ effects implied by perturbative QCD. The quantitative implementation of the latter is described within the unified scheme incorporating both Altarelli-Parisi evolution and the double $ln^2(1/x)$ resummation. The double $ln^2(1/x)$ effects are found to be important in the region of $x$ which can possibly be probed at HERA. Predictions for the polarized gluon distribution $\Delta G(x,Q^2)$ at low $x$ are also given.
1508.06133
Veronica Sanz
Veronica Sanz and Jack Setford
Composite Higgses with seesaw EWSB
19 pages, 2 figures. v2: JHEP version, mistake corrected, discussion on tuning and top-partners extended
null
10.1007/JHEP12(2015)154
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a new class of Composite Higgs models in which electroweak symmetry is broken by a seesaw-like mechanism. If a global symmetry is broken sequentially at different scales, two sets of pseudo-Goldstone bosons will arise, one set being typically heavier than the other. If two Composite Higgs doublets mix, then the mass-squared of the lighter state can be driven negative, and induce EWSB. We illustrate with the example $SO(6) \rightarrow SO(5) \rightarrow SO(4)$, and derive an estimate of the light Higgs potential. We find that the introduction of an extra scale can ease many of the tensions present in conventional Composite Higgs models, especially those related to fine-tuning. In particular we find that we can significantly raise the upper bound on the mass of the elusive top partners.
[ { "created": "Tue, 25 Aug 2015 12:45:04 GMT", "version": "v1" }, { "created": "Wed, 9 Dec 2015 20:14:27 GMT", "version": "v2" } ]
2016-01-27
[ [ "Sanz", "Veronica", "" ], [ "Setford", "Jack", "" ] ]
We introduce a new class of Composite Higgs models in which electroweak symmetry is broken by a seesaw-like mechanism. If a global symmetry is broken sequentially at different scales, two sets of pseudo-Goldstone bosons will arise, one set being typically heavier than the other. If two Composite Higgs doublets mix, then the mass-squared of the lighter state can be driven negative, and induce EWSB. We illustrate with the example $SO(6) \rightarrow SO(5) \rightarrow SO(4)$, and derive an estimate of the light Higgs potential. We find that the introduction of an extra scale can ease many of the tensions present in conventional Composite Higgs models, especially those related to fine-tuning. In particular we find that we can significantly raise the upper bound on the mass of the elusive top partners.
0706.2753
P. Q. Hung
P. Q. Hung
Implications of right-handed neutrinos with electroweak-scale masses
11 pages, no figures. Prepared for Les Rencontres de Physique de La Vallee d'Aoste, March 4-10, 2007, La Thuile, Vallee d'Aoste, Italy
FrascatiPhys.Ser.44:313-323,2007
null
null
hep-ph
null
The possibility of constructing a model in which right-handed neutrinos have electroweak-scale masses as well as being {\em non-sterile} was espoused in Ref. 1. In this talk, I will review the ideas and results of Ref. 1 and discuss its implications for colliders such as the Tevatron, LHC and ILC.
[ { "created": "Tue, 19 Jun 2007 09:59:16 GMT", "version": "v1" } ]
2008-11-26
[ [ "Hung", "P. Q.", "" ] ]
The possibility of constructing a model in which right-handed neutrinos have electroweak-scale masses as well as being {\em non-sterile} was espoused in Ref. 1. In this talk, I will review the ideas and results of Ref. 1 and discuss its implications for colliders such as the Tevatron, LHC and ILC.
1902.04222
Jesse Thaler
Cari Cesarotti, Yotam Soreq, Matthew J. Strassler, Jesse Thaler, Wei Xue
Searching in CMS Open Data for Dimuon Resonances with Substantial Transverse Momentum
21 pages, 8 figures, 4 tables; v2: approximate version to appear in PRD, with references added and some discussions expanded
Phys. Rev. D 100, 015021 (2019)
10.1103/PhysRevD.100.015021
MIT-CTP/5044, CERN-TH-2018-188
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study dimuon events in 2.11/fb of 7 TeV pp collisions, using CMS Open Data, and search for a narrow dimuon resonance with moderate mass (14-66 GeV) and substantial transverse momentum (pT). Applying dimuon pT cuts of 25 GeV and 60 GeV, we explore two overlapping samples: one with isolated muons, and one with prompt muons without an isolation requirement. Using the latter sample requires information about detector effects and QCD backgrounds, which we obtain directly from the CMS Open Data. We present model-independent limits on the product of cross section, branching fraction, acceptance, and efficiencies. These limits are stronger, relative to a corresponding inclusive search without a pT cut, by factors of as much as nine. Our "pT-enhanced" dimuon search strategy provides improved sensitivity to models in which a new particle is produced mainly in the decay of something heavier, as could occur, for example, in decays of the Higgs boson or of a TeV-scale top partner. An implementation of this method with the current 13 TeV data should improve the sensitivity to such signals further by roughly an order of magnitude.
[ { "created": "Tue, 12 Feb 2019 02:57:56 GMT", "version": "v1" }, { "created": "Fri, 19 Jul 2019 23:37:54 GMT", "version": "v2" } ]
2019-07-24
[ [ "Cesarotti", "Cari", "" ], [ "Soreq", "Yotam", "" ], [ "Strassler", "Matthew J.", "" ], [ "Thaler", "Jesse", "" ], [ "Xue", "Wei", "" ] ]
We study dimuon events in 2.11/fb of 7 TeV pp collisions, using CMS Open Data, and search for a narrow dimuon resonance with moderate mass (14-66 GeV) and substantial transverse momentum (pT). Applying dimuon pT cuts of 25 GeV and 60 GeV, we explore two overlapping samples: one with isolated muons, and one with prompt muons without an isolation requirement. Using the latter sample requires information about detector effects and QCD backgrounds, which we obtain directly from the CMS Open Data. We present model-independent limits on the product of cross section, branching fraction, acceptance, and efficiencies. These limits are stronger, relative to a corresponding inclusive search without a pT cut, by factors of as much as nine. Our "pT-enhanced" dimuon search strategy provides improved sensitivity to models in which a new particle is produced mainly in the decay of something heavier, as could occur, for example, in decays of the Higgs boson or of a TeV-scale top partner. An implementation of this method with the current 13 TeV data should improve the sensitivity to such signals further by roughly an order of magnitude.
1406.7476
Shivani Gupta
Shivani Gupta, Sin Kyu Kang, C. S. Kim
Renormalization Group Evolution of Neutrino Parameters in Presence of Seesaw Threshold Effects and Majorana Phases
Discussion modified in Sec 4, references added. Version to appear in Nucl. Phys. B
null
10.1016/j.nuclphysb.2015.01.026
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the renormalization group evolution (RGE) for different mixing scenarios in the presence of seesaw threshold effects from high energy scale (GUT) to the low electroweak (EW) scale in the Standard Model (SM) and Minimal Supersymmetric Standard Model (MSSM). We consider four mixing scenarios namely Tri-Bimaximal Mixing, Bimaximal Mixing, Hexagonal Mixing and Golden Ratio Mixing which come from different flavor symmetries at the GUT scale. We find that the Majorana phases play an important role in the RGE running of these mixing patterns along with the seesaw threshold corrections. We present a comparative study of the RGE of all these mixing scenarios both with and without Majorana CP phases when seesaw threshold corrections are taken into consideration. We find that in the absence of these Majorana phases both the RGE running and seesaw effects may lead to $\theta_{13}<$ 5$^\circ$ at low energies both in the SM and MSSM. However, if the Majorana phases are incorporated to the mixing matrix the running can be enhanced both in the SM and MSSM. Even by incorporating non zero Majorana CP phases in the SM, we do not get $\theta_{13}$ in its present 3$\sigma$ range. The current values of the two mass squared differences and mixing angles including $\theta_{13}$ can be produced in the MSSM case with tan$\beta$ = 10 and non zero Majorana CP phases at low energy. We also calculate the order of effective Majorana mass and Jarlskog Invariant for each scenario under consideration.
[ { "created": "Sun, 29 Jun 2014 09:07:05 GMT", "version": "v1" }, { "created": "Sun, 1 Feb 2015 06:31:10 GMT", "version": "v2" } ]
2015-05-20
[ [ "Gupta", "Shivani", "" ], [ "Kang", "Sin Kyu", "" ], [ "Kim", "C. S.", "" ] ]
We examine the renormalization group evolution (RGE) for different mixing scenarios in the presence of seesaw threshold effects from high energy scale (GUT) to the low electroweak (EW) scale in the Standard Model (SM) and Minimal Supersymmetric Standard Model (MSSM). We consider four mixing scenarios namely Tri-Bimaximal Mixing, Bimaximal Mixing, Hexagonal Mixing and Golden Ratio Mixing which come from different flavor symmetries at the GUT scale. We find that the Majorana phases play an important role in the RGE running of these mixing patterns along with the seesaw threshold corrections. We present a comparative study of the RGE of all these mixing scenarios both with and without Majorana CP phases when seesaw threshold corrections are taken into consideration. We find that in the absence of these Majorana phases both the RGE running and seesaw effects may lead to $\theta_{13}<$ 5$^\circ$ at low energies both in the SM and MSSM. However, if the Majorana phases are incorporated to the mixing matrix the running can be enhanced both in the SM and MSSM. Even by incorporating non zero Majorana CP phases in the SM, we do not get $\theta_{13}$ in its present 3$\sigma$ range. The current values of the two mass squared differences and mixing angles including $\theta_{13}$ can be produced in the MSSM case with tan$\beta$ = 10 and non zero Majorana CP phases at low energy. We also calculate the order of effective Majorana mass and Jarlskog Invariant for each scenario under consideration.
1506.00623
Luca Vecchi
Luca Vecchi
A dangerous irrelevant UV-completion of the composite Higgs
14 pages, JHEP style, added discussion of vacuum alignment (first presented at https://lattice.llnl.gov/meetings/2015/beyond-standard-model-physics/presentations/2015-04-24/1630_VECCHI.pdf)
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
One of the most challenging hurdles to the construction of realistic composite Higgs models is the generation of Yukawa couplings for the Standard Model fermions. This problem can be successfully addressed in approximate conformal theories that admit a marginally relevant mixing between composite fermionic operators and the SM fermions. I argue that SU(3) gauge theories with light Dirac flavors in the fundamental representation feature all the ingredients under theoretical control, including a strongly-coupled IR fixed point, composite partners for all Standard Model fermions, absence of Landau poles at low energy, and a realistic phenomenology. These models acquire the status of compelling UV-completions of the SM if some spin-1/2 baryon operator has scaling dimension close to 2.5 within the conformal window, a possibility that can only be assessed via non-perturbative methods like lattice QCD. A distinctive collider signature is long-lived hadrons with fractional charges. Vacuum alignment is controlled by the Nambu-Goldstone bosons of the coset SU(4)xSU(4)/SU(4). With a technically natural choice of mixing for the top-quark, the exotic scalars with electro-weak charges acquire large positive masses and a compelling custodial-symmetric phenomenology is obtained. In the decoupling limit the symmetry breaking pattern effectively reduces to SU(4)->Sp(4) with a light Higgs.
[ { "created": "Mon, 1 Jun 2015 19:46:01 GMT", "version": "v1" }, { "created": "Sun, 10 Jul 2016 12:29:04 GMT", "version": "v2" } ]
2016-07-12
[ [ "Vecchi", "Luca", "" ] ]
One of the most challenging hurdles to the construction of realistic composite Higgs models is the generation of Yukawa couplings for the Standard Model fermions. This problem can be successfully addressed in approximate conformal theories that admit a marginally relevant mixing between composite fermionic operators and the SM fermions. I argue that SU(3) gauge theories with light Dirac flavors in the fundamental representation feature all the ingredients under theoretical control, including a strongly-coupled IR fixed point, composite partners for all Standard Model fermions, absence of Landau poles at low energy, and a realistic phenomenology. These models acquire the status of compelling UV-completions of the SM if some spin-1/2 baryon operator has scaling dimension close to 2.5 within the conformal window, a possibility that can only be assessed via non-perturbative methods like lattice QCD. A distinctive collider signature is long-lived hadrons with fractional charges. Vacuum alignment is controlled by the Nambu-Goldstone bosons of the coset SU(4)xSU(4)/SU(4). With a technically natural choice of mixing for the top-quark, the exotic scalars with electro-weak charges acquire large positive masses and a compelling custodial-symmetric phenomenology is obtained. In the decoupling limit the symmetry breaking pattern effectively reduces to SU(4)->Sp(4) with a light Higgs.
0908.3770
Jackson Wu
Jackson Wu
Non-Supersymmetric New Physics from Moeller Scattering
5 pages, 3 figures, talk given at "The 2009 Europhysics Conference on High Energy Physics", 16-22 July 2009, Krakow, Poland
PoS EPS-HEP2009 2009:251,2009
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study in an effective operator approach how the effects of new physics from various scenarios containing extra $Z'$ gauge bosons or doubly charged scalars can affect, and thus be tested by the precision polarized Moeller scattering experiment. We give Wilson coefficients for various classes of models, and we deduce constraints on the parameter space of the relevant coupling constants and mixing angles from the results of the SLAC E158 experiment, and that projected from the future high precision JLAB experiment.
[ { "created": "Wed, 26 Aug 2009 08:51:50 GMT", "version": "v1" } ]
2014-11-20
[ [ "Wu", "Jackson", "" ] ]
We study in an effective operator approach how the effects of new physics from various scenarios containing extra $Z'$ gauge bosons or doubly charged scalars can affect, and thus be tested by the precision polarized Moeller scattering experiment. We give Wilson coefficients for various classes of models, and we deduce constraints on the parameter space of the relevant coupling constants and mixing angles from the results of the SLAC E158 experiment, and that projected from the future high precision JLAB experiment.
hep-ph/0408354
Cristina Manuel
Cristina Manuel
Transport Coefficients in Color Superconducting Quark Matter
5 pages; talk given in Strong and Electroweak Matter (SEWM 2004), Helsini, Finland, June 2004
null
10.1142/9789812702159_0044
null
hep-ph
null
Transport coefficients of dense quark matter are needed to study properties of compact stars. They can tell us about the cooling, vibrational and rotational properties of the star. We report below a computation of the shear viscosity in the CFL phase at low temperature T. CFL quark matter behaves as a superfluid, and at low T its transport properties are dominated by the collisions of superfluid phonons.
[ { "created": "Tue, 31 Aug 2004 14:41:41 GMT", "version": "v1" } ]
2017-08-23
[ [ "Manuel", "Cristina", "" ] ]
Transport coefficients of dense quark matter are needed to study properties of compact stars. They can tell us about the cooling, vibrational and rotational properties of the star. We report below a computation of the shear viscosity in the CFL phase at low temperature T. CFL quark matter behaves as a superfluid, and at low T its transport properties are dominated by the collisions of superfluid phonons.
2307.00394
Mukesh Kumar
Karabo Mosala, Pramod Sharma, Mukesh Kumar, Ashok Goyal
Axion-Like Particles at future $e^- p$ collider
11 pages, 8 figures; Version accepted for publication in EPJC
Eur. Phys. J. C (2024) 84:44
10.1140/epjc/s10052-024-12401-9
null
hep-ph
http://creativecommons.org/publicdomain/zero/1.0/
In this work, we explore the possibilities of producing Axion-Like Particles (ALPs) in a future $e^-p$ collider. Specifically, we focus on the proposed Large Hadron electron collider (LHeC), which can achieve a center-of-mass energy of $\sqrt{s} \approx 1.3$~TeV, enabling us to probe relatively high ALP masses with $m_a \lesssim 300$~GeV. The production of ALPs can occur through various channels, including $W^+W^-$, $\gamma\gamma$, $ZZ$, and $Z\gamma$-fusion within the collider environment. To investigate this, we conduct a comprehensive analysis that involves estimating the production cross section and constraining the limits on the associated couplings of ALPs, namely $g_{WW}$, $g_{\gamma\gamma}$, $g_{ZZ}$, and $g_{Z\gamma}$. To achieve this, we utilize a multiple-bin $\chi^2$ analysis on sensitive differential distributions. Through the analysis of these distributions, we determine upper bounds on the associated couplings within the mass range of 5~GeV $\leq m_a \leq$ 300~GeV. The obtained upper bounds are of the order of ${\cal O}(10^{-1})$ for $g_{\gamma\gamma}$ ($g_{WW}$, $g_{ZZ}$, $g_{Z\gamma}$) in $m_a \in$~[5, 200 (300)]~GeV considering an integrated luminosity of 1~ab$^{-1}$. Furthermore, we compare the results of our study with those obtained from other available experiments. We emphasize the limits obtained through our analysis and showcase the potential of the LHeC in probing the properties of ALPs.
[ { "created": "Sat, 1 Jul 2023 17:45:30 GMT", "version": "v1" }, { "created": "Thu, 11 Jan 2024 18:48:43 GMT", "version": "v2" } ]
2024-01-19
[ [ "Mosala", "Karabo", "" ], [ "Sharma", "Pramod", "" ], [ "Kumar", "Mukesh", "" ], [ "Goyal", "Ashok", "" ] ]
In this work, we explore the possibilities of producing Axion-Like Particles (ALPs) in a future $e^-p$ collider. Specifically, we focus on the proposed Large Hadron electron collider (LHeC), which can achieve a center-of-mass energy of $\sqrt{s} \approx 1.3$~TeV, enabling us to probe relatively high ALP masses with $m_a \lesssim 300$~GeV. The production of ALPs can occur through various channels, including $W^+W^-$, $\gamma\gamma$, $ZZ$, and $Z\gamma$-fusion within the collider environment. To investigate this, we conduct a comprehensive analysis that involves estimating the production cross section and constraining the limits on the associated couplings of ALPs, namely $g_{WW}$, $g_{\gamma\gamma}$, $g_{ZZ}$, and $g_{Z\gamma}$. To achieve this, we utilize a multiple-bin $\chi^2$ analysis on sensitive differential distributions. Through the analysis of these distributions, we determine upper bounds on the associated couplings within the mass range of 5~GeV $\leq m_a \leq$ 300~GeV. The obtained upper bounds are of the order of ${\cal O}(10^{-1})$ for $g_{\gamma\gamma}$ ($g_{WW}$, $g_{ZZ}$, $g_{Z\gamma}$) in $m_a \in$~[5, 200 (300)]~GeV considering an integrated luminosity of 1~ab$^{-1}$. Furthermore, we compare the results of our study with those obtained from other available experiments. We emphasize the limits obtained through our analysis and showcase the potential of the LHeC in probing the properties of ALPs.
0812.3980
Fayet
Pierre Fayet
U(1)_A symmetry in two-doublet models, U bosons or light scalars, and psi and Upsilon decays
10 pages, to appear in Physics Letters B
Phys.Lett.B675:267-271,2009
10.1016/j.physletb.2009.03.078
LPTENS-08/70
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
psi and Upsilon decays may be used to search for light neutral spin-1 or spin-0 bosons associated with a broken extra-U(1) symmetry, local or global, acting axially on quarks and leptons, as may be present in supersymmetric theories with a lambda H_1 H_2 S superpotential term. Recent data on Upsilon --> gamma + invisible neutral constrain an axial, pseudoscalar or scalar coupling to b to f_bA < 4 10^-7 m_U(MeV)/ sqrt B_inv, f_bP < 4 10^-3/ sqrt B_inv or f_bS < 6 10^-3/ sqrt B_inv, respectively. This also constrains, from universality properties, couplings to electrons to f_eA < 4 10^-7 m_U(MeV)/ sqrt B_inv, f_eP < 4 10^-7/ sqrt B_inv or f_eS < 6 10^-7/ sqrt B_inv. The pseudoscalar a (possibly traded for a light gauge boson, or scalar particle) should then be, for invisible decays of the new boson, for > 96 % singlet and < 4 % doublet, for tan beta > 1. Or, more generally, < 4 % /(tan^2 beta B_inv) doublet, which implies a very small rate for the corresponding psi decay, B (psi --> gamma + neutral) B_inv <~ 10^-6/ tan^4 beta. Similar results are obtained for new spin-1 or spin-0 neutral bosons decaying into mu+ mu-.
[ { "created": "Sat, 20 Dec 2008 16:29:20 GMT", "version": "v1" }, { "created": "Fri, 10 Apr 2009 10:45:29 GMT", "version": "v2" } ]
2011-03-28
[ [ "Fayet", "Pierre", "" ] ]
psi and Upsilon decays may be used to search for light neutral spin-1 or spin-0 bosons associated with a broken extra-U(1) symmetry, local or global, acting axially on quarks and leptons, as may be present in supersymmetric theories with a lambda H_1 H_2 S superpotential term. Recent data on Upsilon --> gamma + invisible neutral constrain an axial, pseudoscalar or scalar coupling to b to f_bA < 4 10^-7 m_U(MeV)/ sqrt B_inv, f_bP < 4 10^-3/ sqrt B_inv or f_bS < 6 10^-3/ sqrt B_inv, respectively. This also constrains, from universality properties, couplings to electrons to f_eA < 4 10^-7 m_U(MeV)/ sqrt B_inv, f_eP < 4 10^-7/ sqrt B_inv or f_eS < 6 10^-7/ sqrt B_inv. The pseudoscalar a (possibly traded for a light gauge boson, or scalar particle) should then be, for invisible decays of the new boson, for > 96 % singlet and < 4 % doublet, for tan beta > 1. Or, more generally, < 4 % /(tan^2 beta B_inv) doublet, which implies a very small rate for the corresponding psi decay, B (psi --> gamma + neutral) B_inv <~ 10^-6/ tan^4 beta. Similar results are obtained for new spin-1 or spin-0 neutral bosons decaying into mu+ mu-.
1812.10975
Tord Riemann
Khiem Hong Phan (Univ. of Science, Vietnam National University, Ho Chi Minh City) and Tord Riemann (DESY and Univ. of Silesia)
Scalar 1-loop Feynman integrals as meromorphic functions in space-time dimension d
9 pages, 3 tables
null
10.1016/j.physletb.2019.02.044
DESY 17-079, HCMUS-19-01, KW 18-004
hep-ph
http://creativecommons.org/licenses/by-sa/4.0/
The long-standing problem of representing the general massive one-loop Feynman integral as a meromorphic function of the space-time dimension $d$ has been solved for the basis of scalar one- to four-point functions with indices one. In 2003 the solution of difference equations in the space-time dimension allowed to determine the necessary classes of special functions: self-energies need ordinary logarithms and Gauss hypergeometric functions $_2F_1$, vertices need additionally Kamp\'{e} de F\'{e}riet-Appell functions $F_1$, and box integrals also Lauricella-Saran functions $F_S$. In this study, alternative recursive Mellin-Barnes representations are used for the representation of $n$-point functions in terms of $(n-1)$-point functions. The approach enabled the first derivation of explicit solutions for the Feynman integrals at arbitrary kinematics. In this article, we scetch our new representations for the general massive vertex and box Feynman integrals and derive a numerical approach for the necessary Appell functions $F_1$ and Saran functions $F_S$ at arbitrary kinematical arguments.
[ { "created": "Fri, 28 Dec 2018 12:39:36 GMT", "version": "v1" } ]
2019-03-06
[ [ "Phan", "Khiem Hong", "", "Univ. of Science, Vietnam National University, Ho Chi\n Minh City" ], [ "Riemann", "Tord", "", "DESY and Univ. of Silesia" ] ]
The long-standing problem of representing the general massive one-loop Feynman integral as a meromorphic function of the space-time dimension $d$ has been solved for the basis of scalar one- to four-point functions with indices one. In 2003 the solution of difference equations in the space-time dimension allowed to determine the necessary classes of special functions: self-energies need ordinary logarithms and Gauss hypergeometric functions $_2F_1$, vertices need additionally Kamp\'{e} de F\'{e}riet-Appell functions $F_1$, and box integrals also Lauricella-Saran functions $F_S$. In this study, alternative recursive Mellin-Barnes representations are used for the representation of $n$-point functions in terms of $(n-1)$-point functions. The approach enabled the first derivation of explicit solutions for the Feynman integrals at arbitrary kinematics. In this article, we scetch our new representations for the general massive vertex and box Feynman integrals and derive a numerical approach for the necessary Appell functions $F_1$ and Saran functions $F_S$ at arbitrary kinematical arguments.
hep-ph/9512270
Kotikov Anatoly
A.V.Kotikov (ENSLAPP and JINR)
The Gegenbauer Polynomial Technique: the evaluation of a class of Feynman diagrams
10 pages, Latex without figures
Phys.Lett. B375 (1996) 240-248
10.1016/0370-2693(96)00226-2
ENSLAPP-A-568/95
hep-ph hep-th
null
We extend Gegenbauer Polynomials technique to evaluate a class of complicated Feynman diagrams. New results in the form of $_3F_2$-hypergeometrical series of unit argument, are presented. As a by-product, we present a new transformation rule for $_3F_2$-hypergeometric series with argument $-1$.
[ { "created": "Mon, 11 Dec 1995 10:24:22 GMT", "version": "v1" } ]
2009-10-28
[ [ "Kotikov", "A. V.", "", "ENSLAPP and JINR" ] ]
We extend Gegenbauer Polynomials technique to evaluate a class of complicated Feynman diagrams. New results in the form of $_3F_2$-hypergeometrical series of unit argument, are presented. As a by-product, we present a new transformation rule for $_3F_2$-hypergeometric series with argument $-1$.
1011.6096
Kim Maltman
Kim Maltman
Status of the Lattice and Tau Decay Determinations of alpha_s
Prepared for the Proceedings of the 5th International Conference on Quarks and Nuclear Physics, Beijing, China, Sept. 21-26, 2009
Chin.Phys.C34:3150,2010
10.1088/1674-1137/34/9/040
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The two highest precision determinations of alpha_s(M_Z^2), that based on the analysis of short-distance-sensitive lattice observables, and that based on an analysis of hadronic tau decay data, have, until very recently, given results which are not in good agreement. I review new versions of these analyses which bring the two determinations into excellent agreement, and discuss prospects for additional future improvements.
[ { "created": "Sun, 28 Nov 2010 22:06:11 GMT", "version": "v1" } ]
2015-05-20
[ [ "Maltman", "Kim", "" ] ]
The two highest precision determinations of alpha_s(M_Z^2), that based on the analysis of short-distance-sensitive lattice observables, and that based on an analysis of hadronic tau decay data, have, until very recently, given results which are not in good agreement. I review new versions of these analyses which bring the two determinations into excellent agreement, and discuss prospects for additional future improvements.
hep-ph/9211255
Felix Schlumpf
Felix Schlumpf
Relativistic Constituent Quark Model for Baryons
(latex, 76 pp, 16 figures, ps-file available) PhD Thesis, Zurich, July 1992
null
null
null
hep-ph nucl-th
null
The electroweak properties of nucleons and hyperons are calculated in a relativistic constituent quark model. The baryons are treated as three quark bound states, and the diagrams of perturbation theory are considered on the light front. The electroweak properties of the baryons are of nonperturbative nature and can be represented by one-loop diagrams. We consider different extensions of the simplest model: quark form factors, configuration mixing of the wave function, asymmetric wave function, wave function different from the one of a harmonic oscillator valid up to energies of more than 30 GeV$^2$. A comprehensive study of various baryonic properties is given: elastic form factors of the nucleon, magnetic moments of the baryon octet, semileptonic weak form factors. This analysis also gives the Kobayashi-Maskawa matrix element $V_{us}$ and a sound symmetry breaking scheme for the Cabibbo theory. A consistent physical picture appears in this work. The nucleon consists of an unmixed, symmetric three quark state, the wave function of the hyperons is however asymmetric with a spin-isospin-0 diquark. Only for the strangeness-changing weak decay do we need nontrivial form factors.
[ { "created": "Mon, 16 Nov 1992 23:19:44 GMT", "version": "v1" } ]
2009-09-25
[ [ "Schlumpf", "Felix", "" ] ]
The electroweak properties of nucleons and hyperons are calculated in a relativistic constituent quark model. The baryons are treated as three quark bound states, and the diagrams of perturbation theory are considered on the light front. The electroweak properties of the baryons are of nonperturbative nature and can be represented by one-loop diagrams. We consider different extensions of the simplest model: quark form factors, configuration mixing of the wave function, asymmetric wave function, wave function different from the one of a harmonic oscillator valid up to energies of more than 30 GeV$^2$. A comprehensive study of various baryonic properties is given: elastic form factors of the nucleon, magnetic moments of the baryon octet, semileptonic weak form factors. This analysis also gives the Kobayashi-Maskawa matrix element $V_{us}$ and a sound symmetry breaking scheme for the Cabibbo theory. A consistent physical picture appears in this work. The nucleon consists of an unmixed, symmetric three quark state, the wave function of the hyperons is however asymmetric with a spin-isospin-0 diquark. Only for the strangeness-changing weak decay do we need nontrivial form factors.
hep-ph/9409204
null
J. Bartelski and S. Tatur
From unpolarized to polarized quark distributions in the nucleon
10 pages, Latex, 4 postscript figures appended as an uuencoded file
Acta Phys.Polon.B26:913-920,1995
null
NCAC-277-94
hep-ph
null
Starting from Martin, Roberts and Stirling fit for unpolarized deep inelastic structure functions and using the newest experimental data on spin asymmetries we get a fit which provides polarized quark distributions. We analyze the behaviour of such functions near $x$ equal to 1. The first moments of these distributions are also discussed. Our fit prefers combination of proton and neutron data versus proton-deuteron one.
[ { "created": "Thu, 1 Sep 1994 15:54:52 GMT", "version": "v1" } ]
2014-11-17
[ [ "Bartelski", "J.", "" ], [ "Tatur", "S.", "" ] ]
Starting from Martin, Roberts and Stirling fit for unpolarized deep inelastic structure functions and using the newest experimental data on spin asymmetries we get a fit which provides polarized quark distributions. We analyze the behaviour of such functions near $x$ equal to 1. The first moments of these distributions are also discussed. Our fit prefers combination of proton and neutron data versus proton-deuteron one.
1709.02372
Ivan Vitev
Samuel Aronson, Evan Borras, Brunel Odegard, Rishi Sharma, Ivan Vitev
Collisional and thermal dissociation of $J/\psi$ and $\Upsilon$ states at the LHC
8 pages, 8 eps figures; 2 figures and references added, introduction restructured; version to appear in PLB
null
10.1016/j.physletb.2018.01.038
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present new results for the suppression of high transverse momentum charmonium [$J/\psi, \psi(2S)$] and bottomonium [$\Upsilon(1S),\Upsilon(2S),\Upsilon(3S)$] states in Pb+Pb collisions at the Large Hadron Collider. Our theoretical formalism combines the collisional dissociation of quarkonia, as they propagate in the quark-gluon plasma, with the thermal wavefunction effects due to the screening of the $Q\bar{Q}$ attractive potential in the medium. We find that a good description of the relative suppression of the ground and higher excited quarkonium states, transverse momentum and centrality distributions is achieved, when comparison to measurements at a center-of-mass energy of 2.76 TeV is performed. Theoretical predictions for the highest Pb+Pb center-of-mass energy of 5.02 TeV at the LHC, where new experimental results are being finalized, are also presented.
[ { "created": "Thu, 7 Sep 2017 17:48:37 GMT", "version": "v1" }, { "created": "Fri, 26 Jan 2018 03:08:05 GMT", "version": "v2" } ]
2018-04-04
[ [ "Aronson", "Samuel", "" ], [ "Borras", "Evan", "" ], [ "Odegard", "Brunel", "" ], [ "Sharma", "Rishi", "" ], [ "Vitev", "Ivan", "" ] ]
We present new results for the suppression of high transverse momentum charmonium [$J/\psi, \psi(2S)$] and bottomonium [$\Upsilon(1S),\Upsilon(2S),\Upsilon(3S)$] states in Pb+Pb collisions at the Large Hadron Collider. Our theoretical formalism combines the collisional dissociation of quarkonia, as they propagate in the quark-gluon plasma, with the thermal wavefunction effects due to the screening of the $Q\bar{Q}$ attractive potential in the medium. We find that a good description of the relative suppression of the ground and higher excited quarkonium states, transverse momentum and centrality distributions is achieved, when comparison to measurements at a center-of-mass energy of 2.76 TeV is performed. Theoretical predictions for the highest Pb+Pb center-of-mass energy of 5.02 TeV at the LHC, where new experimental results are being finalized, are also presented.
1507.01373
Michael Spira
Urs Langenegger, Michael Spira, Ivo Strebel
Testing the Higgs Boson Coupling to Gluons
12 pages, 6 figures, references added
null
null
PSI-PR-15-07
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the possibility to separate in gluon fusion loop-induced Higgs boson production from point-like production. The Higgs boson is reconstructed in the Hgg final state at very large transverse momentum. Using the Higgs boson yields (normalized to the overall rate) and the shape of the Higgs boson pt distribution the two hypotheses can be separated with 2 standard deviations with an integrated luminosity of about 500 fb^-1. The largest experimental uncertainty affecting this estimate is the background event yield. The theoretical uncertainties from missing top mass effects are large, but can be decreased with dedicated calculations.
[ { "created": "Mon, 6 Jul 2015 10:06:50 GMT", "version": "v1" }, { "created": "Fri, 24 Jul 2015 15:46:31 GMT", "version": "v2" } ]
2015-07-27
[ [ "Langenegger", "Urs", "" ], [ "Spira", "Michael", "" ], [ "Strebel", "Ivo", "" ] ]
We study the possibility to separate in gluon fusion loop-induced Higgs boson production from point-like production. The Higgs boson is reconstructed in the Hgg final state at very large transverse momentum. Using the Higgs boson yields (normalized to the overall rate) and the shape of the Higgs boson pt distribution the two hypotheses can be separated with 2 standard deviations with an integrated luminosity of about 500 fb^-1. The largest experimental uncertainty affecting this estimate is the background event yield. The theoretical uncertainties from missing top mass effects are large, but can be decreased with dedicated calculations.
hep-ph/9605458
null
H. M. Asatrian, G.K. Yeghiyan
Higgs Boson Masses in NMSSM with Spontaneous CP-violation
15 pages, 7 figures
null
10.1142/S0217732396002769
Preprint YERPHI-1470(7)-96
hep-ph
null
The Higgs boson mass problem is considered in the next-to-minimal supersymmetric standard model for the case of the spontaneous CP violation. The renormalization group equations for the gauge, Yukawa and scalar coupling constants, the effective Higgs potential and lower experimental bounds on Higgs boson and chargino masses are analyzed. The restrictions on the Higgs boson masses are found.
[ { "created": "Fri, 31 May 1996 13:26:37 GMT", "version": "v1" }, { "created": "Sat, 29 Jun 1996 07:39:07 GMT", "version": "v2" }, { "created": "Thu, 4 Jul 1996 09:50:52 GMT", "version": "v3" }, { "created": "Fri, 5 Jul 1996 09:13:39 GMT", "version": "v4" }, { "created": "Thu, 15 Aug 1996 13:31:40 GMT", "version": "v5" }, { "created": "Sat, 17 Aug 1996 09:46:22 GMT", "version": "v6" }, { "created": "Sat, 31 Aug 1996 09:43:01 GMT", "version": "v7" } ]
2009-10-28
[ [ "Asatrian", "H. M.", "" ], [ "Yeghiyan", "G. K.", "" ] ]
The Higgs boson mass problem is considered in the next-to-minimal supersymmetric standard model for the case of the spontaneous CP violation. The renormalization group equations for the gauge, Yukawa and scalar coupling constants, the effective Higgs potential and lower experimental bounds on Higgs boson and chargino masses are analyzed. The restrictions on the Higgs boson masses are found.
hep-ph/9411229
Vladimir Braun
M.Beneke and V.M Braun
Naive nonabelianization and resummation of fermion bubble chains
12 pages, LATEX, no figures
Phys.Lett. B348 (1995) 513-520
10.1016/0370-2693(95)00184-M
DESY 94-200
hep-ph
null
We propose to extend the Brodsky-Lepage-Mackenzie scale-fixing prescription by resumming exactly any number of one-loop vacuum polarization insertions into one-loop diagrams. In this way, one makes maximal use of the information contained in one-loop perturbative corrections combined with the one-loop running of the effective coupling. The scale ambiguity at leading order is converted into an intrinsic uncertainty of perturbative approximations induced by IR renormalons. Practical implementation of this resummation requires only knowledge of one-loop radiative corrections with non-vanishing gluon mass. We find that higher order corrections to the pole mass and the top quark decay width are dominated by renormalons already in low orders and demonstrate the impact of eliminating the pole mass on the convergence of the perturbative series.
[ { "created": "Sat, 5 Nov 1994 16:49:50 GMT", "version": "v1" } ]
2009-10-28
[ [ "Beneke", "M.", "" ], [ "Braun", "V. M", "" ] ]
We propose to extend the Brodsky-Lepage-Mackenzie scale-fixing prescription by resumming exactly any number of one-loop vacuum polarization insertions into one-loop diagrams. In this way, one makes maximal use of the information contained in one-loop perturbative corrections combined with the one-loop running of the effective coupling. The scale ambiguity at leading order is converted into an intrinsic uncertainty of perturbative approximations induced by IR renormalons. Practical implementation of this resummation requires only knowledge of one-loop radiative corrections with non-vanishing gluon mass. We find that higher order corrections to the pole mass and the top quark decay width are dominated by renormalons already in low orders and demonstrate the impact of eliminating the pole mass on the convergence of the perturbative series.
1312.1628
John M. Campbell
John M. Campbell, R. Keith Ellis and Ciaran Williams
Bounding the Higgs width at the LHC: complementary results from $H \to WW$
8 pages, 5 figures
Phys. Rev. D 89, 053011 (2014)
10.1103/PhysRevD.89.053011
FERMILAB-PUB-13-553-T
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the potential of the process $gg \to H \to WW$ to provide bounds on the Higgs width. Recent studies using off-shell $H\rightarrow ZZ$ events have shown that Run 1 LHC data can constrain the Higgs width, $\Gamma_H < (25-45) \Gamma_{H}^{\rm SM}$. Using 20 fb-1 of 8 TeV ATLAS data, we estimate a bound on the Higgs boson width from the WW channel between $\Gamma_H < (100-500) \Gamma_H^{SM}$. The large spread in limits is due to the range of cuts applied in the existing experimental analysis. The stricter cuts designed to search for the on-shell Higgs boson limit the potential number of off-shell events, weakening the constraints. As some of the cuts are lifted the bounds improve. We show that there is potential in the high transverse mass region to produce upper bounds of the order of $(25-50) \Gamma_H^{SM}$, depending strongly on the level of systematic uncertainty that can be obtained. Thus, if these systematics can be controlled, a constraint on the Higgs boson width from the $H \to WW$ decay mode can complement a corresponding limit from $H \to ZZ$.
[ { "created": "Thu, 5 Dec 2013 17:45:40 GMT", "version": "v1" } ]
2014-03-26
[ [ "Campbell", "John M.", "" ], [ "Ellis", "R. Keith", "" ], [ "Williams", "Ciaran", "" ] ]
We investigate the potential of the process $gg \to H \to WW$ to provide bounds on the Higgs width. Recent studies using off-shell $H\rightarrow ZZ$ events have shown that Run 1 LHC data can constrain the Higgs width, $\Gamma_H < (25-45) \Gamma_{H}^{\rm SM}$. Using 20 fb-1 of 8 TeV ATLAS data, we estimate a bound on the Higgs boson width from the WW channel between $\Gamma_H < (100-500) \Gamma_H^{SM}$. The large spread in limits is due to the range of cuts applied in the existing experimental analysis. The stricter cuts designed to search for the on-shell Higgs boson limit the potential number of off-shell events, weakening the constraints. As some of the cuts are lifted the bounds improve. We show that there is potential in the high transverse mass region to produce upper bounds of the order of $(25-50) \Gamma_H^{SM}$, depending strongly on the level of systematic uncertainty that can be obtained. Thus, if these systematics can be controlled, a constraint on the Higgs boson width from the $H \to WW$ decay mode can complement a corresponding limit from $H \to ZZ$.
hep-ph/9803297
Apostolos Pilaftsis
Apostolos Pilaftsis (Max-Planck-Inst., Munich)
CP-Odd Tadpole Renormalization of Higgs Scalar-Pseudoscalar Mixing
22 pages, LaTeX
Phys.Rev. D58 (1998) 096010
10.1103/PhysRevD.58.096010
MPI/PhT/98-21
hep-ph
null
We consider an Abelian model with a CP-conserving Higgs potential spanned by two complex Higgs fields. The CP invariance of the Higgs potential is then broken explicitly beyond the Born approximation by introducing soft-CP-violating Yukawa interactions. Based on the non-renormalization theorem, we derive the consistency conditions under which a CP-odd counterterm exists and, at the same time, renders the one-loop-induced mixing of a CP-even Higgs boson with a CP-odd Higgs scalar ultra-violet finite. The novel CP-odd tadpole renormalization may then be determined from the minimization constraints on the Higgs potential. Finally, we discuss the phenomenological consequences of the so-generated CP-violating scalar-pseudoscalar mixing for the electric dipole moments of neutron, electron and muon.
[ { "created": "Tue, 10 Mar 1998 15:37:59 GMT", "version": "v1" } ]
2009-10-31
[ [ "Pilaftsis", "Apostolos", "", "Max-Planck-Inst., Munich" ] ]
We consider an Abelian model with a CP-conserving Higgs potential spanned by two complex Higgs fields. The CP invariance of the Higgs potential is then broken explicitly beyond the Born approximation by introducing soft-CP-violating Yukawa interactions. Based on the non-renormalization theorem, we derive the consistency conditions under which a CP-odd counterterm exists and, at the same time, renders the one-loop-induced mixing of a CP-even Higgs boson with a CP-odd Higgs scalar ultra-violet finite. The novel CP-odd tadpole renormalization may then be determined from the minimization constraints on the Higgs potential. Finally, we discuss the phenomenological consequences of the so-generated CP-violating scalar-pseudoscalar mixing for the electric dipole moments of neutron, electron and muon.
hep-ph/0505120
Rena Ciftci
A. K. Ciftci, R. Ciftci, S. Sultansoy
The Fourth SM Family Neutrino at Future Linear Colliders
16 pages, 3 figures, 10 tables
Phys.Rev.D72:053006,2005
10.1103/PhysRevD.72.053006
null
hep-ph
null
It is known that Flavor Democracy favors the existence of the fourth standard model (SM) family. In order to give nonzero masses for the first three family fermions Flavor Democracy has to be slightly broken. A parametrization for democracy breaking, which gives the correct values for fundamental fermion masses and, at the same time, predicts quark and lepton CKM matrices in a good agreement with the experimental data, is proposed. The pair productions of the fourth SM family Dirac $(\nu_{4})$ and Majorana $(N_{1})$ neutrinos at future linear colliders with $\sqrt{s}=500$ GeV, 1 TeV and 3 TeV are considered. The cross section for the process $e^{+}e^{-}\to\nu_{4}\bar {\nu_{4}}(N_{1}N_{1})$ and the branching ratios for possible decay modes of the both neutrinos are determined. The decays of the fourth family neutrinos into muon channels $(\nu_{4}(N_{1})\to\mu^{\pm}W^{\mp})$ provide cleanest signature at $e^{+}e^{-}$ colliders. Meanwhile, in our parametrization this channel is dominant. $W$ bosons produced in decays of the fourth family neutrinos will be seen in detector as either di-jets or isolated leptons. As an example we consider the production of 200 GeV mass fourth family neutrinos at $\sqrt{s}=500$ GeV linear colliders by taking into account di-muon plus four-jet events as signatures.
[ { "created": "Fri, 13 May 2005 14:56:24 GMT", "version": "v1" }, { "created": "Sat, 14 May 2005 07:36:36 GMT", "version": "v2" } ]
2014-11-18
[ [ "Ciftci", "A. K.", "" ], [ "Ciftci", "R.", "" ], [ "Sultansoy", "S.", "" ] ]
It is known that Flavor Democracy favors the existence of the fourth standard model (SM) family. In order to give nonzero masses for the first three family fermions Flavor Democracy has to be slightly broken. A parametrization for democracy breaking, which gives the correct values for fundamental fermion masses and, at the same time, predicts quark and lepton CKM matrices in a good agreement with the experimental data, is proposed. The pair productions of the fourth SM family Dirac $(\nu_{4})$ and Majorana $(N_{1})$ neutrinos at future linear colliders with $\sqrt{s}=500$ GeV, 1 TeV and 3 TeV are considered. The cross section for the process $e^{+}e^{-}\to\nu_{4}\bar {\nu_{4}}(N_{1}N_{1})$ and the branching ratios for possible decay modes of the both neutrinos are determined. The decays of the fourth family neutrinos into muon channels $(\nu_{4}(N_{1})\to\mu^{\pm}W^{\mp})$ provide cleanest signature at $e^{+}e^{-}$ colliders. Meanwhile, in our parametrization this channel is dominant. $W$ bosons produced in decays of the fourth family neutrinos will be seen in detector as either di-jets or isolated leptons. As an example we consider the production of 200 GeV mass fourth family neutrinos at $\sqrt{s}=500$ GeV linear colliders by taking into account di-muon plus four-jet events as signatures.
1608.01834
Jos Vermaseren A
Franz Herzog, Ben Ruijl, Takahiro Ueda, J.A.M. Vermaseren (NIKHEF, Amsterdam), Andreas Vogt (Liverpool U., Dept. Math.)
FORM, Diagrams and Topologies
16 pages, LaTeX (PoS style) using axodraw2.sty. To appear in the proceedings of `Loops & Legs 2016', Leipzig (Germany), April 2016
null
null
NIKHEF 2016-040, LTH 1096
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss a number of FORM features that are essential in the automatic processing of very large numbers of diagrams as used in the Forcer program for 4-loop massless propagator diagrams. Most of these features are new.
[ { "created": "Fri, 5 Aug 2016 11:18:09 GMT", "version": "v1" } ]
2016-08-08
[ [ "Herzog", "Franz", "", "NIKHEF,\n Amsterdam" ], [ "Ruijl", "Ben", "", "NIKHEF,\n Amsterdam" ], [ "Ueda", "Takahiro", "", "NIKHEF,\n Amsterdam" ], [ "Vermaseren", "J. A. M.", "", "NIKHEF,\n Amsterdam" ], [ "Vogt", "Andreas", "", "Liverpool U., Dept. Math." ] ]
We discuss a number of FORM features that are essential in the automatic processing of very large numbers of diagrams as used in the Forcer program for 4-loop massless propagator diagrams. Most of these features are new.
1503.03577
Xiao-Gang He
Xiao-Gang He, Tzu-Chiang Yuan
Glueball Production via Gluonic Penguin B Decays
Latex 14 pages with 2 figures. Significant update from the older version of arXiv:hep-ph/0612108. Version to appear in Eur. Phys. J. C
null
10.1140/epjc/s10052-015-3354-4
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study glueball $G$ production in gluonic penguin decay $B\to G + X_s$, using the next-to-leading order $b\to s g^*$ gluonic penguin interaction and effective couplings of a glueball to two perturbative gluons. Subsequent decays of a scalar glueball are described by using techniques of effective chiral Lagrangian to incorporate the interaction between a glueball and pseudoscalar mesons. Mixing effects between the pure glueball with other mesons are considered. Identifying the $f_0(1710)$ to be a scalar glueball, we find that both the top and charm penguin to be important and obtain a sizable branching ratio for $B\to f_0(1710) + X_s$ of order $1.3\times 10^{-4} (f/0.07\mbox{GeV}^{-1})^2$, where the effective coupling strength $f$ is estimated to be $0.07$ GeV$^{-1}$ using experimental data for the branching ratio of $f_0(1710) \to K \overline K$ based on chiral Lagrangian estimate. An alternative perturbative QCD based estimation of $f$ is a factor of 20 larger, which would imply a much enhanced branching ratio. Glueball production from this rare semi-inclusive $B$ decay can be probed at the LHCb and Belle II to narrow down the allowed parameter space. Similar branching ratio is expected for the pseudoscalar glueball. We also briefly comment on the case of vector and tensor glueballs.
[ { "created": "Thu, 12 Mar 2015 04:07:30 GMT", "version": "v1" }, { "created": "Sat, 14 Mar 2015 12:58:31 GMT", "version": "v2" } ]
2015-06-24
[ [ "He", "Xiao-Gang", "" ], [ "Yuan", "Tzu-Chiang", "" ] ]
We study glueball $G$ production in gluonic penguin decay $B\to G + X_s$, using the next-to-leading order $b\to s g^*$ gluonic penguin interaction and effective couplings of a glueball to two perturbative gluons. Subsequent decays of a scalar glueball are described by using techniques of effective chiral Lagrangian to incorporate the interaction between a glueball and pseudoscalar mesons. Mixing effects between the pure glueball with other mesons are considered. Identifying the $f_0(1710)$ to be a scalar glueball, we find that both the top and charm penguin to be important and obtain a sizable branching ratio for $B\to f_0(1710) + X_s$ of order $1.3\times 10^{-4} (f/0.07\mbox{GeV}^{-1})^2$, where the effective coupling strength $f$ is estimated to be $0.07$ GeV$^{-1}$ using experimental data for the branching ratio of $f_0(1710) \to K \overline K$ based on chiral Lagrangian estimate. An alternative perturbative QCD based estimation of $f$ is a factor of 20 larger, which would imply a much enhanced branching ratio. Glueball production from this rare semi-inclusive $B$ decay can be probed at the LHCb and Belle II to narrow down the allowed parameter space. Similar branching ratio is expected for the pseudoscalar glueball. We also briefly comment on the case of vector and tensor glueballs.
1202.5491
Yonatan Kahn
Yonatan Kahn and Jesse Thaler
Locality in Theory Space
40 pages, 11 figures; v2: references and clarifications added; v3: version accepted by JHEP
JHEP 1207:007,2012
10.1007/JHEP07(2012)007
MIT-CTP 4346
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Locality is a guiding principle for constructing realistic quantum field theories. Compactified theories offer an interesting context in which to think about locality, since interactions can be nonlocal in the compact directions while still being local in the extended ones. In this paper, we study locality in "theory space", four-dimensional Lagrangians which are dimensional deconstructions of five-dimensional Yang-Mills. In explicit ultraviolet (UV) completions, one can understand the origin of theory space locality by the irrelevance of nonlocal operators. From an infrared (IR) point of view, though, theory space locality does not appear to be a special property, since the lowest-lying Kaluza-Klein (KK) modes are simply described by a gauged nonlinear sigma model, and locality imposes seemingly arbitrary constraints on the KK spectrum and interactions. We argue that these constraints are nevertheless important from an IR perspective, since they affect the four-dimensional cutoff of the theory where high energy scattering hits strong coupling. Intriguingly, we find that maximizing this cutoff scale implies five-dimensional locality. In this way, theory space locality is correlated with weak coupling in the IR, independent of UV considerations. We briefly comment on other scenarios where maximizing the cutoff scale yields interesting physics, including theory space descriptions of QCD and deconstructions of anti-de Sitter space.
[ { "created": "Fri, 24 Feb 2012 16:24:17 GMT", "version": "v1" }, { "created": "Fri, 6 Apr 2012 17:25:30 GMT", "version": "v2" }, { "created": "Wed, 27 Jun 2012 18:03:55 GMT", "version": "v3" } ]
2012-07-10
[ [ "Kahn", "Yonatan", "" ], [ "Thaler", "Jesse", "" ] ]
Locality is a guiding principle for constructing realistic quantum field theories. Compactified theories offer an interesting context in which to think about locality, since interactions can be nonlocal in the compact directions while still being local in the extended ones. In this paper, we study locality in "theory space", four-dimensional Lagrangians which are dimensional deconstructions of five-dimensional Yang-Mills. In explicit ultraviolet (UV) completions, one can understand the origin of theory space locality by the irrelevance of nonlocal operators. From an infrared (IR) point of view, though, theory space locality does not appear to be a special property, since the lowest-lying Kaluza-Klein (KK) modes are simply described by a gauged nonlinear sigma model, and locality imposes seemingly arbitrary constraints on the KK spectrum and interactions. We argue that these constraints are nevertheless important from an IR perspective, since they affect the four-dimensional cutoff of the theory where high energy scattering hits strong coupling. Intriguingly, we find that maximizing this cutoff scale implies five-dimensional locality. In this way, theory space locality is correlated with weak coupling in the IR, independent of UV considerations. We briefly comment on other scenarios where maximizing the cutoff scale yields interesting physics, including theory space descriptions of QCD and deconstructions of anti-de Sitter space.
0902.1434
Yi Liao
Yi Liao (1 and 2 and 3), Ji-Yuan Liu (1), Guo-Zhu Ning (1) ((1) Nankai U., (2) CHEP, Peking U., (3) KITPC, CAS)
Radiative Neutrino Mass in Type III Seesaw Model
21 pages, 1 figure; v2: added 3 sentences in sec 4 for clarifications, version published on 7 Apr 2009 in PR D79, 073003 (2009)
Phys.Rev.D79:073003,2009
10.1103/PhysRevD.79.073003
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The simplest type III seesaw model as originally proposed introduces one lepton triplet. It thus contains four active neutrinos, two massive and two massless at tree level. We determine the radiative masses that the latter receive first at two loops. The masses are generally so tiny that they are definitely excluded by the oscillation data, if the heavy leptons are not very heavy, say, within the reach of LHC. To accommodate the data on masses, the seesaw scale must be as large as the scale of grand unification. This indicates that the most economical type III model would entail no new physics at low energies beyond the tiny neutrino masses.
[ { "created": "Mon, 9 Feb 2009 13:08:39 GMT", "version": "v1" }, { "created": "Sun, 12 Apr 2009 13:15:51 GMT", "version": "v2" } ]
2009-04-22
[ [ "Liao", "Yi", "", "1 and 2 and 3" ], [ "Liu", "Ji-Yuan", "" ], [ "Ning", "Guo-Zhu", "" ] ]
The simplest type III seesaw model as originally proposed introduces one lepton triplet. It thus contains four active neutrinos, two massive and two massless at tree level. We determine the radiative masses that the latter receive first at two loops. The masses are generally so tiny that they are definitely excluded by the oscillation data, if the heavy leptons are not very heavy, say, within the reach of LHC. To accommodate the data on masses, the seesaw scale must be as large as the scale of grand unification. This indicates that the most economical type III model would entail no new physics at low energies beyond the tiny neutrino masses.
hep-ph/9709470
Leonard S. Kisslinger
Leonard S. Kisslinger (Carnegie Mellon University),Zhenping Li (Peking University)
Sigma Signal for Hybrid Baryon Decay
Latex file
Phys.Lett. B445 (1999) 271-273
10.1016/S0370-2693(98)01503-2
null
hep-ph
null
We develop an ansatze of the sigma enhancement of the I=0, L=0 $\pi$-$\pi$ scattering amplitude as arising from a low-energy glueball pole. Using this picture we estimate the $\pi^0\pi^0$ to $\pi^0$ branching ratio for the decays of the Roper resonance, which we previously found to be a hybrid in our QCD sum rule calculation. We find that the sigma decay might be a good signal for gluonic components of hadrons.
[ { "created": "Fri, 26 Sep 1997 13:53:36 GMT", "version": "v1" } ]
2009-10-30
[ [ "Kisslinger", "Leonard S.", "", "Carnegie Mellon University" ], [ "Li", "Zhenping", "", "Peking\n University" ] ]
We develop an ansatze of the sigma enhancement of the I=0, L=0 $\pi$-$\pi$ scattering amplitude as arising from a low-energy glueball pole. Using this picture we estimate the $\pi^0\pi^0$ to $\pi^0$ branching ratio for the decays of the Roper resonance, which we previously found to be a hybrid in our QCD sum rule calculation. We find that the sigma decay might be a good signal for gluonic components of hadrons.
1011.0909
Vincenzo Barone
Vincenzo Barone, Franco Bradamante, Anna Martin
Transverse-Spin and Transverse-Momentum Effects in High-Energy Processes
95 pages
Prog.Part.Nucl.Phys.65:267-333,2010
10.1016/j.ppnp.2010.07.003
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The state of the art concerning transverse-spin and transverse-momentum phenomena in hard hadronic reactions is reviewed. An account is given of single-spin and azimuthal asymmetries in semiinclusive deep inelastic scattering, e^+ e^- annihilation, Drell-Yan production, and hadroproduction. The ongoing experiments and the main theoretical frameworks are described in the first part of the paper. The second part is devoted to the experimental findings and their phenomenological interpretations. A brief discussion of the perspectives of future measurements is finally presented.
[ { "created": "Wed, 3 Nov 2010 15:10:13 GMT", "version": "v1" } ]
2010-12-01
[ [ "Barone", "Vincenzo", "" ], [ "Bradamante", "Franco", "" ], [ "Martin", "Anna", "" ] ]
The state of the art concerning transverse-spin and transverse-momentum phenomena in hard hadronic reactions is reviewed. An account is given of single-spin and azimuthal asymmetries in semiinclusive deep inelastic scattering, e^+ e^- annihilation, Drell-Yan production, and hadroproduction. The ongoing experiments and the main theoretical frameworks are described in the first part of the paper. The second part is devoted to the experimental findings and their phenomenological interpretations. A brief discussion of the perspectives of future measurements is finally presented.
hep-ph/0505093
Andrew Psallidas
A. Psallidas
Majorana Neutrino Masses from Flavor Symmetries
Based on a talk given in the "Workshop on Recent Advances in Particle Physics and Cosmology", Thessaloniki 2005
null
null
null
hep-ph
null
In this talk we discuss the implications of the Minimal Supersymmetric Standard Model augmented by a single U(1) anomalous family symmetry for neutrino masses and mixing angles. The left-handed neutrino states are provided with Majorana masses through a dimension-five operator in the absence of right handed neutrino components. Assuming symmetric lepton mass matrices, the model predicts inverse hierarchical neutrino mass spectrum, theta_13=0 and large mixing while at the same time it provides acceptable mass matrices for the charged fermions.
[ { "created": "Wed, 11 May 2005 12:18:35 GMT", "version": "v1" } ]
2007-05-23
[ [ "Psallidas", "A.", "" ] ]
In this talk we discuss the implications of the Minimal Supersymmetric Standard Model augmented by a single U(1) anomalous family symmetry for neutrino masses and mixing angles. The left-handed neutrino states are provided with Majorana masses through a dimension-five operator in the absence of right handed neutrino components. Assuming symmetric lepton mass matrices, the model predicts inverse hierarchical neutrino mass spectrum, theta_13=0 and large mixing while at the same time it provides acceptable mass matrices for the charged fermions.
hep-ph/9605246
Motohiko Yoshimura
M. Yoshimura
Baryogenesis and thermal history after inflation
25 pages, LATEX file. Lecture delivered at KOSEF-JSPS Winter School, held at Seoul, Korea, February 21-28, 1996. To appear in the Proceedings to be published in Journal of Korean Physical Society
J.KoreanPhys.Soc.29:S236,1996
null
TU/96/500
hep-ph
null
The basic idea of baryogenesis is lectured to introduce non-experts to this subject. Some recent topics, necessarily subjective in view of short time limitation, are also presented to show how the initial condition for baryogenesis is realized in the new framework of inflation.
[ { "created": "Wed, 8 May 1996 05:32:26 GMT", "version": "v1" } ]
2008-11-26
[ [ "Yoshimura", "M.", "" ] ]
The basic idea of baryogenesis is lectured to introduce non-experts to this subject. Some recent topics, necessarily subjective in view of short time limitation, are also presented to show how the initial condition for baryogenesis is realized in the new framework of inflation.
hep-ph/0212367
Yan QiShu
Q.S. Yan, and D.S. Du
The renormalization of the effective gauge theory with spontaneous symmetry breaking: the $SU(2)\times U(1)$ case
58 figures, one revtex file, 69 pages in total; we establish a modifed power counting rule to make our procedure consistent. Comparison with the full theory is made. The problem of unitarity violation is addressed
null
null
null
hep-ph
null
We formulate the electroweak chiral Lagrangian in its mass eigenstates, and study the its one-loop renormalization and provide its renormalization group equations to the same order, so as to complete it as the low energy effective theory of the standard model below a few TeV. In order to make our computation consistent, we have provided a modified power counting rule to estimate the contributions of higher loop and higher operators. As one of the application of its renormalization group equations, we analyze the solution to the effects of the Higgs scalar. We find that similar to the SU(2) case, that the triple anomalous couplings are sensitive to the quartic couplings (here $\al_5$). While the quadratic anomalous couplings are not sensitive, due to the large leading contributions and the accidental cancellation. The differences in the triple anomalous couplings between the direct method and renormalization group equation method are well within the detection power of the LHC and LC, if the Higgs scalar is not too heavy (say, 300 or 400 GeV). We also suggest a new mechanism to generate the negative $S$ parameter through the radiative corrections of the anomalous couplings. Comparison of the renormalization group equation method and direct methods is provided in the full theory, the standard model, to reveal the basic differences of them. The problem of the unitarity violation is also addressed for our assumption in the modified power counting rule.
[ { "created": "Thu, 26 Dec 2002 04:59:31 GMT", "version": "v1" }, { "created": "Fri, 24 Jan 2003 18:46:37 GMT", "version": "v2" }, { "created": "Fri, 20 Jun 2003 09:33:12 GMT", "version": "v3" } ]
2007-05-23
[ [ "Yan", "Q. S.", "" ], [ "Du", "D. S.", "" ] ]
We formulate the electroweak chiral Lagrangian in its mass eigenstates, and study the its one-loop renormalization and provide its renormalization group equations to the same order, so as to complete it as the low energy effective theory of the standard model below a few TeV. In order to make our computation consistent, we have provided a modified power counting rule to estimate the contributions of higher loop and higher operators. As one of the application of its renormalization group equations, we analyze the solution to the effects of the Higgs scalar. We find that similar to the SU(2) case, that the triple anomalous couplings are sensitive to the quartic couplings (here $\al_5$). While the quadratic anomalous couplings are not sensitive, due to the large leading contributions and the accidental cancellation. The differences in the triple anomalous couplings between the direct method and renormalization group equation method are well within the detection power of the LHC and LC, if the Higgs scalar is not too heavy (say, 300 or 400 GeV). We also suggest a new mechanism to generate the negative $S$ parameter through the radiative corrections of the anomalous couplings. Comparison of the renormalization group equation method and direct methods is provided in the full theory, the standard model, to reveal the basic differences of them. The problem of the unitarity violation is also addressed for our assumption in the modified power counting rule.
hep-ph/9505212
null
R. Casalbuoni, P. Chiappetta, D. Dominici, A. Fiandrino and R. Gatto
Top Quark Production in Extended Bess Model
13 pages, LaTeX, 4 figures
Z.Phys. C69 (1996) 519-524
null
CPT-95/P.3176; UGVA-DPT 1995/04-887
hep-ph
null
We study top production at Tevatron collider in the extended BESS model, which is an effective lagrangian parametrization of a dynamical symmetry breaking of the electroweak symmetry. The existence of a colored octet of gauge vector bosons can increase top production at a rate still consistent with recent experimental data and lead to distorsions in the transverse momentum spectrum of the top.
[ { "created": "Tue, 2 May 1995 14:44:35 GMT", "version": "v1" } ]
2009-09-25
[ [ "Casalbuoni", "R.", "" ], [ "Chiappetta", "P.", "" ], [ "Dominici", "D.", "" ], [ "Fiandrino", "A.", "" ], [ "Gatto", "R.", "" ] ]
We study top production at Tevatron collider in the extended BESS model, which is an effective lagrangian parametrization of a dynamical symmetry breaking of the electroweak symmetry. The existence of a colored octet of gauge vector bosons can increase top production at a rate still consistent with recent experimental data and lead to distorsions in the transverse momentum spectrum of the top.
hep-ph/9411395
Marek Jezabek
R. Harlander, M. Je\.zabek, J.H. K\"uhn and T. Teubner
Polarization in Top Quark Pair Production near Threshold
11 pages, LaTex (uses epsf.sty, 3 ps-figures appended as extra uuencoded file). The complete paper, including figures, is also available via anonymous ftp at ftp://ttpux2.physik.uni-karlsruhe.de/ttp94-28/ttp94-28.ps, or via www at http://ttpux2.physik.uni-karlsruhe.de/preprints.html
Phys.Lett. B346 (1995) 137-142
10.1016/0370-2693(94)01668-3
TTP94-28
hep-ph
null
The polarization dependent momentum distributions of top quarks and their decay products are calculated for $t\bar t$ production at future $e^+e^-$ colliders with polarized beams. The Green function formalism is applied to this reaction near energy threshold. The Lippmann--Schwinger equations for the $S$-wave and $P$-wave Green functions are solved numerically for the QCD chromostatic potential given by the two-loop formula at large momentum transfers and Richardson ansatz at intermediate and small ones. It is demonstrated that for the longitudinally polarized electron beam an optimally polarized sample of top quarks can be produced.
[ { "created": "Fri, 25 Nov 1994 18:32:13 GMT", "version": "v1" } ]
2009-10-28
[ [ "Harlander", "R.", "" ], [ "Jeżabek", "M.", "" ], [ "Kühn", "J. H.", "" ], [ "Teubner", "T.", "" ] ]
The polarization dependent momentum distributions of top quarks and their decay products are calculated for $t\bar t$ production at future $e^+e^-$ colliders with polarized beams. The Green function formalism is applied to this reaction near energy threshold. The Lippmann--Schwinger equations for the $S$-wave and $P$-wave Green functions are solved numerically for the QCD chromostatic potential given by the two-loop formula at large momentum transfers and Richardson ansatz at intermediate and small ones. It is demonstrated that for the longitudinally polarized electron beam an optimally polarized sample of top quarks can be produced.
hep-ph/0510271
Wanda Maria Alberico
W.M. Alberico, P. Czerski, A. Lavagno, M. Nardi, V. Soma'
Signals of non-extensive statistical mechanics in high-energy nuclear collisions
13 pages, 3 figures
null
null
null
hep-ph
null
Starting from the presence of non-ideal plasma effects due to strongly coupled plasma in the early stage of relativistic heavy-ion collisions, we investigate, from a phenomenological point of view, the relevance of non-conventional statistical mechanics effects on the rapidity spectra of net proton yield at AGS, SPS and RHIC. We show that the broad rapidity shape measured at RHIC can be very well reproduced in the framework of a non-linear relativistic Fokker-Planck equation which incorporates non-extensive statistics and anomalous diffusion.
[ { "created": "Thu, 20 Oct 2005 16:39:25 GMT", "version": "v1" }, { "created": "Wed, 31 May 2006 17:30:47 GMT", "version": "v2" } ]
2007-05-23
[ [ "Alberico", "W. M.", "" ], [ "Czerski", "P.", "" ], [ "Lavagno", "A.", "" ], [ "Nardi", "M.", "" ], [ "Soma'", "V.", "" ] ]
Starting from the presence of non-ideal plasma effects due to strongly coupled plasma in the early stage of relativistic heavy-ion collisions, we investigate, from a phenomenological point of view, the relevance of non-conventional statistical mechanics effects on the rapidity spectra of net proton yield at AGS, SPS and RHIC. We show that the broad rapidity shape measured at RHIC can be very well reproduced in the framework of a non-linear relativistic Fokker-Planck equation which incorporates non-extensive statistics and anomalous diffusion.
2108.11868
Kodai Sakurai
Masashi Aiko, Shinya Kanemura, Kodai Sakurai
Radiative corrections to decays of charged Higgs bosons in two Higgs doublet models
68 pages, 17 figures; revised version as accepted by Nuclear Physics B
null
null
OU-HET 1100, TU 1128
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the next-to-leading order (NLO) electroweak (EW) corrections to decay rates of charged Higgs bosons for various decay modes in the four types of two Higgs doublet models (THDMs) with the softly broken discrete Z_2 symmetry. Decay branching ratios of charged Higgs bosons are evaluated including NLO EW corrections, as well as QCD corrections up to next-to-next-to-leading order (NNLO). We comprehensively study impacts of the NLO EW corrections to the branching ratios in nearly alignment scenarios where the couplings constants of the Higgs boson with the mass of 125 GeV are close to those predicted in the standard model. Furthermore, in the nearly alignment scenario, we discuss whether or not the four types of THDMs can be distinguished via the decays of charged Higgs bosons. We find that characteristic predictions of charged Higgs branching ratios can be obtained for all types of the THDMs, by which each type of the THDMs are separated, and information on the internal parameters of the THDMs can be extracted from the magnitudes of the various decay branching ratios.
[ { "created": "Thu, 26 Aug 2021 15:50:24 GMT", "version": "v1" }, { "created": "Thu, 21 Oct 2021 10:10:58 GMT", "version": "v2" } ]
2021-10-22
[ [ "Aiko", "Masashi", "" ], [ "Kanemura", "Shinya", "" ], [ "Sakurai", "Kodai", "" ] ]
We calculate the next-to-leading order (NLO) electroweak (EW) corrections to decay rates of charged Higgs bosons for various decay modes in the four types of two Higgs doublet models (THDMs) with the softly broken discrete Z_2 symmetry. Decay branching ratios of charged Higgs bosons are evaluated including NLO EW corrections, as well as QCD corrections up to next-to-next-to-leading order (NNLO). We comprehensively study impacts of the NLO EW corrections to the branching ratios in nearly alignment scenarios where the couplings constants of the Higgs boson with the mass of 125 GeV are close to those predicted in the standard model. Furthermore, in the nearly alignment scenario, we discuss whether or not the four types of THDMs can be distinguished via the decays of charged Higgs bosons. We find that characteristic predictions of charged Higgs branching ratios can be obtained for all types of the THDMs, by which each type of the THDMs are separated, and information on the internal parameters of the THDMs can be extracted from the magnitudes of the various decay branching ratios.
hep-ph/9907466
Jorge Crispim Romao
J. C. Romao
Neutrino Masses from Broken R-Parity
11 pages, 11 Figures in Postscript. Talk given at the International Workshop on Physics Beyond the Standard Model: From Theory to Experiment, Valencia, Spain, May 3-8 1999
Nucl.Phys.Proc.Suppl. 81 (2000) 231-241
10.1016/S0920-5632(99)00881-6
FISIST/13-99/CFIF
hep-ph
null
We review models where R-parity is broken, either spontaneously or explicitly. In this last case we consider the situation where R-parity is broken via bilinear terms in the superpotential. We show that although at tree level only one neutrino gets mass, at one--loop level all three neutrinos became massive. We study the conditions under which bimaximal mixing can be achieved and show that the masses can be in the correct ranges needed for solving the atmospheric and solar neutrino problems.
[ { "created": "Fri, 23 Jul 1999 11:22:32 GMT", "version": "v1" } ]
2009-10-31
[ [ "Romao", "J. C.", "" ] ]
We review models where R-parity is broken, either spontaneously or explicitly. In this last case we consider the situation where R-parity is broken via bilinear terms in the superpotential. We show that although at tree level only one neutrino gets mass, at one--loop level all three neutrinos became massive. We study the conditions under which bimaximal mixing can be achieved and show that the masses can be in the correct ranges needed for solving the atmospheric and solar neutrino problems.
2204.01580
Joran Angevaare
J. R. Angevaare, G. Bertone, A. P. Colijn, M. P. Decowski, B. J. Kavanagh
Complementarity of direct detection experiments in search of light Dark Matter
19 pages, 7 figures
JCAP10(2022)004
10.1088/1475-7516/2022/10/004
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dark Matter experiments searching for Weakly interacting massive particles (WIMPs) primarily use nuclear recoils (NRs) in their attempt to detect WIMPs. Migdal-induced electronic recoils (ERs) provide additional sensitivity to light Dark Matter with $\mathcal{O}(\text{GeV}/c^2)$ masses. In this work, we use Bayesian inference to find the parameter space where future detectors like XENONnT and SuperCDMS SNOLAB will be able to detect WIMP Dark Matter through NRs, Migdal-induced ERs or a combination thereof. We identify regions where each detector is best at constraining the Dark Matter mass and spin independent cross-section and infer where two or more detection configurations are complementary to constraining these Dark Matter parameters through a combined analysis.
[ { "created": "Mon, 4 Apr 2022 15:30:57 GMT", "version": "v1" }, { "created": "Wed, 31 Aug 2022 08:47:07 GMT", "version": "v2" } ]
2022-12-22
[ [ "Angevaare", "J. R.", "" ], [ "Bertone", "G.", "" ], [ "Colijn", "A. P.", "" ], [ "Decowski", "M. P.", "" ], [ "Kavanagh", "B. J.", "" ] ]
Dark Matter experiments searching for Weakly interacting massive particles (WIMPs) primarily use nuclear recoils (NRs) in their attempt to detect WIMPs. Migdal-induced electronic recoils (ERs) provide additional sensitivity to light Dark Matter with $\mathcal{O}(\text{GeV}/c^2)$ masses. In this work, we use Bayesian inference to find the parameter space where future detectors like XENONnT and SuperCDMS SNOLAB will be able to detect WIMP Dark Matter through NRs, Migdal-induced ERs or a combination thereof. We identify regions where each detector is best at constraining the Dark Matter mass and spin independent cross-section and infer where two or more detection configurations are complementary to constraining these Dark Matter parameters through a combined analysis.
1205.6811
Dan Hooper
Matthew R. Buckley and Dan Hooper
Implications of a 130 GeV Gamma-Ray Line for Dark Matter
7 pages, 4 figures
null
10.1103/PhysRevD.86.043524
FERMILAB-PUB-12-259-A
hep-ph astro-ph.CO astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent reports of a gamma-ray line feature at ~130 GeV in data from the Fermi Gamma-Ray Space Telescope have generated a great deal of interest in models in which dark matter particles annihilate with a sizable cross section to final states including photons. In this article, we take a model-independent approach, and discuss a number of possibilities for dark matter candidates which could potentially generate such a feature. While we identify several scenarios which could lead to such a gamma-ray line, these models are each fairly constrained. In particular, viable models require large couplings (g>1-3), and additional charged particles with masses in the range of approximately ~130-200 GeV. Furthermore, lower energy gamma-ray constraints from the Galactic Center force us to consider scenarios in which the dark matter annihilates in the early universe through velocity-suppressed processes, or to final states which yield relatively few gamma-rays (such as electrons, muons or neutrinos). An exception to these conclusions can be found in models in which the dark matter annihilates to heavy intermediate states which decay to photons to generate a line-like gamma-ray spectrum.
[ { "created": "Wed, 30 May 2012 20:00:36 GMT", "version": "v1" }, { "created": "Wed, 13 Jun 2012 16:45:00 GMT", "version": "v2" }, { "created": "Thu, 19 Jul 2012 19:58:00 GMT", "version": "v3" } ]
2013-05-30
[ [ "Buckley", "Matthew R.", "" ], [ "Hooper", "Dan", "" ] ]
Recent reports of a gamma-ray line feature at ~130 GeV in data from the Fermi Gamma-Ray Space Telescope have generated a great deal of interest in models in which dark matter particles annihilate with a sizable cross section to final states including photons. In this article, we take a model-independent approach, and discuss a number of possibilities for dark matter candidates which could potentially generate such a feature. While we identify several scenarios which could lead to such a gamma-ray line, these models are each fairly constrained. In particular, viable models require large couplings (g>1-3), and additional charged particles with masses in the range of approximately ~130-200 GeV. Furthermore, lower energy gamma-ray constraints from the Galactic Center force us to consider scenarios in which the dark matter annihilates in the early universe through velocity-suppressed processes, or to final states which yield relatively few gamma-rays (such as electrons, muons or neutrinos). An exception to these conclusions can be found in models in which the dark matter annihilates to heavy intermediate states which decay to photons to generate a line-like gamma-ray spectrum.
1709.03415
Peter H. L. Christiansen
Peter Christiansen
What Quark-Gluon Plasma in small systems might tell us about nucleons
15 pages, 2 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The origin of flow-like effects in small systems, such as those produced in ultra-relativistic proton-proton and proton-lead collisions, is still widely debated. In this paper the goal is to look at possible consequences if indeed a mini-Quark-Gluon Plasma is formed in these collisions. It is argued that this could indicate a duality between the QGP phase and the color fields in hadrons. A qualitative dense field picture is presented for this duality and discussed.
[ { "created": "Mon, 11 Sep 2017 14:46:55 GMT", "version": "v1" } ]
2017-09-12
[ [ "Christiansen", "Peter", "" ] ]
The origin of flow-like effects in small systems, such as those produced in ultra-relativistic proton-proton and proton-lead collisions, is still widely debated. In this paper the goal is to look at possible consequences if indeed a mini-Quark-Gluon Plasma is formed in these collisions. It is argued that this could indicate a duality between the QGP phase and the color fields in hadrons. A qualitative dense field picture is presented for this duality and discussed.
hep-ph/9711263
Zsolt Szep
A. Patkos, P. Petreczky, Zs. Szep
Coupled Gap Equations for the Screening Masses in Hot SU(N) Gauge Theory
15 pages, Latex, 4 eps figures included, uses epsf.sty, added references, corrected typos
Eur.Phys.J.C5:337-344,1998
10.1007/s100520050277
ITP Budapest Rep. 537, BI-TP 97/45
hep-ph
null
Coupled 1-loop gap equations are studied numerically for non-Abelian electric and magnetic screening in various versions of the three-dimensional effective gauge models. Corrections due to higher dimensional and non-local operators are assessed quantitatively. Comparison with numerical Monte-Carlo investigations suggests that quantitative understanding beyond the qualitative features can be achieved only by going beyond the present treatment.
[ { "created": "Sat, 8 Nov 1997 00:23:23 GMT", "version": "v1" }, { "created": "Thu, 18 Dec 1997 20:10:42 GMT", "version": "v2" }, { "created": "Fri, 13 Feb 1998 00:18:15 GMT", "version": "v3" } ]
2011-09-13
[ [ "Patkos", "A.", "" ], [ "Petreczky", "P.", "" ], [ "Szep", "Zs.", "" ] ]
Coupled 1-loop gap equations are studied numerically for non-Abelian electric and magnetic screening in various versions of the three-dimensional effective gauge models. Corrections due to higher dimensional and non-local operators are assessed quantitatively. Comparison with numerical Monte-Carlo investigations suggests that quantitative understanding beyond the qualitative features can be achieved only by going beyond the present treatment.
hep-ph/0510002
Naomichi Suzuki
Naomichi Suzuki and Minoru Biyajima
Relativistic diffusion model and analysis of large transverse momentum distributions
6pages, 4figures, talk at XXXV International Symposium on Multiparticle Dynamics 2005, Kromeriz, Czech Republuc, August 9-15, 2005
null
10.1063/1.2197425
null
hep-ph
null
In order to describe large transverse momentum ($p_T$) distributions observed in high energy nucleus-nucleus collisions, a stochastic model in the three dimensional rapidity space is introduced. The fundamental solution of the radial symmetric diffusion equation is Gaussian-like in radial rapidity. We can also derive a $p_T$ or radial rapidity distribution function, where a distribution of emission center is taken into account. It is applied to the analysis of observed large $p_T$ distributions of charged particles. It is shown that our model approaches to a power function of $p_T$ in the high transverse momentum limit.
[ { "created": "Sat, 1 Oct 2005 01:52:35 GMT", "version": "v1" } ]
2015-06-25
[ [ "Suzuki", "Naomichi", "" ], [ "Biyajima", "Minoru", "" ] ]
In order to describe large transverse momentum ($p_T$) distributions observed in high energy nucleus-nucleus collisions, a stochastic model in the three dimensional rapidity space is introduced. The fundamental solution of the radial symmetric diffusion equation is Gaussian-like in radial rapidity. We can also derive a $p_T$ or radial rapidity distribution function, where a distribution of emission center is taken into account. It is applied to the analysis of observed large $p_T$ distributions of charged particles. It is shown that our model approaches to a power function of $p_T$ in the high transverse momentum limit.
2203.03211
Xiao-Rui Lyu
Hai-Yang Cheng (1), Xiao-Rui Lyu (2), Zhi-Zhong Xing (2,3) (for the STCF working group, (1) Institute of Physics, Academia Sinica, (2) University of Chinese Academy of Sciences, (3) Institute of High Energy Physics)
Charm Physics in the High-Luminosity Super $\tau$-Charm Factory
White Paper on STCF charm physics; contribution to Snowmass 2021
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
This is a white paper on the STCF charm physics contributing to the Snowmass 2021 proceedings in the RF01 working group.
[ { "created": "Mon, 7 Mar 2022 08:51:56 GMT", "version": "v1" } ]
2022-03-08
[ [ "Cheng", "Hai-Yang", "" ], [ "Lyu", "Xiao-Rui", "" ], [ "Xing", "Zhi-Zhong", "" ] ]
This is a white paper on the STCF charm physics contributing to the Snowmass 2021 proceedings in the RF01 working group.
0910.2448
Rosti Konoplich
Rashid M. Djilkibaev and Rostislav V. Konoplich
Reconstruction of $\tilde{\tau}_{1}$ mass at the LHC
13 pages, 4 figures, corrected Table 6 and typos, added references for section 3
Phys.Atom.Nucl.74:90-97,2011
10.1134/S106377881101011X
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The cascade mass reconstruction approach was used for mass reconstruction of the lightest stau produced at the LHC in the cascade decay $\tilde{g} \to \tilde{b} b \to \tilde{\chi}_{2}^{0} b b \to \tilde{\tau}_{1} \tau b b \to \tilde{\chi}_{1}^{0} \tau \tau b b $. The stau mass was reconstructed assuming that masses of gluino, bottom squark and two lightest neutralinos were reconstructed in advance. SUSY data sample sets for the SU3 model point containing 160k events each were generated which corresponded to an integrated luminosity of about $8 \rm fb^{-1}$ at 14 TeV. These events were passed through the AcerDET detector simulator, which parametrized the response of a generic LHC detector. The mass of the $\tilde{\tau}_{1}$ was reconstructed with a precision of about 20% on average.
[ { "created": "Tue, 13 Oct 2009 18:30:14 GMT", "version": "v1" }, { "created": "Mon, 28 Dec 2009 04:44:39 GMT", "version": "v2" } ]
2011-03-17
[ [ "Djilkibaev", "Rashid M.", "" ], [ "Konoplich", "Rostislav V.", "" ] ]
The cascade mass reconstruction approach was used for mass reconstruction of the lightest stau produced at the LHC in the cascade decay $\tilde{g} \to \tilde{b} b \to \tilde{\chi}_{2}^{0} b b \to \tilde{\tau}_{1} \tau b b \to \tilde{\chi}_{1}^{0} \tau \tau b b $. The stau mass was reconstructed assuming that masses of gluino, bottom squark and two lightest neutralinos were reconstructed in advance. SUSY data sample sets for the SU3 model point containing 160k events each were generated which corresponded to an integrated luminosity of about $8 \rm fb^{-1}$ at 14 TeV. These events were passed through the AcerDET detector simulator, which parametrized the response of a generic LHC detector. The mass of the $\tilde{\tau}_{1}$ was reconstructed with a precision of about 20% on average.
hep-ph/0401044
Ernest Ma
Ernest Ma (UC Riverside)
Quarks and Leptons in a Hexagonal Chain
10 pages, including 1 figure
Phys.Lett. B593 (2004) 198
10.1016/j.physletb.2004.04.056
UCRHEP-T369 (Jan 04)
hep-ph
null
The seemingly disparate notions of chiral color and quark-lepton nonuniversality are combined, and shown to be essential to each other as part of an underlying (and unifying) larger symmetry, i.e. supersymmetric SU(3)^6. Both phenomena are accessible experimentally at the TeV energy scale.
[ { "created": "Thu, 8 Jan 2004 21:13:27 GMT", "version": "v1" } ]
2009-11-10
[ [ "Ma", "Ernest", "", "UC Riverside" ] ]
The seemingly disparate notions of chiral color and quark-lepton nonuniversality are combined, and shown to be essential to each other as part of an underlying (and unifying) larger symmetry, i.e. supersymmetric SU(3)^6. Both phenomena are accessible experimentally at the TeV energy scale.
1804.02299
Robert Harlander
R.V. Harlander, J. Klappert, C. Pandini, and A. Papaefstathiou
Exploiting the WH/ZH symmetry in the search for New Physics
22 pages, 10 figures. v2: Minor changes; matches published version
null
10.1140/epjc/s10052-018-6234-x
TTK-17-48, Nikhef 2018-026
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We suggest to isolate the loop-induced gluon-initiated component ($gg\to ZH$) for associated $ZH$ production by using the similarity of the Drell-Yan-like component for $ZH$ production to the $WH$ process. We argue that the cross-section ratio of the latter two processes can be predicted with high theoretical accuracy. Comparing it to the experimental $ZH/WH$ cross-section ratio should allow to probe for New Physics in the $gg\to ZH$ component at the HL-LHC. We consider typical BSM scenarios in order to exemplify the effect they would have on the proposed observable.
[ { "created": "Fri, 6 Apr 2018 14:32:40 GMT", "version": "v1" }, { "created": "Tue, 9 Oct 2018 11:20:50 GMT", "version": "v2" } ]
2018-10-17
[ [ "Harlander", "R. V.", "" ], [ "Klappert", "J.", "" ], [ "Pandini", "C.", "" ], [ "Papaefstathiou", "A.", "" ] ]
We suggest to isolate the loop-induced gluon-initiated component ($gg\to ZH$) for associated $ZH$ production by using the similarity of the Drell-Yan-like component for $ZH$ production to the $WH$ process. We argue that the cross-section ratio of the latter two processes can be predicted with high theoretical accuracy. Comparing it to the experimental $ZH/WH$ cross-section ratio should allow to probe for New Physics in the $gg\to ZH$ component at the HL-LHC. We consider typical BSM scenarios in order to exemplify the effect they would have on the proposed observable.
1102.5327
Alexander Kovner
T. Altinoluk and A. Kovner
Particle Production at High Energy and Large Transverse Momentum - "The Hybrid Formalism" Revisited
null
Phys.Rev.D83:105004,2011
10.1103/PhysRevD.83.105004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the "`hybrid formalism"' for particle production used recently to study saturation effects in single hadron multiplicities at forward rapidities at RHIC and LHC. We point out that at leading twist there is an extra contribution to the formulae used so far, which corresponds to particle production via inelastic scattering of the projectile partons on the target fields. This contribution is expected to be small due to kinematics at very forward rapidities/very high transverse momenta, but should be significant at high momenta and very high energies. This contribution is expected to be most affected by saturation effects and is therefore an interesting object of study in the context of possible onset of saturation at high energies.
[ { "created": "Fri, 25 Feb 2011 20:19:17 GMT", "version": "v1" } ]
2011-05-13
[ [ "Altinoluk", "T.", "" ], [ "Kovner", "A.", "" ] ]
We revisit the "`hybrid formalism"' for particle production used recently to study saturation effects in single hadron multiplicities at forward rapidities at RHIC and LHC. We point out that at leading twist there is an extra contribution to the formulae used so far, which corresponds to particle production via inelastic scattering of the projectile partons on the target fields. This contribution is expected to be small due to kinematics at very forward rapidities/very high transverse momenta, but should be significant at high momenta and very high energies. This contribution is expected to be most affected by saturation effects and is therefore an interesting object of study in the context of possible onset of saturation at high energies.
1208.1177
Wayne W. Repko
Duane A. Dicus and Wayne W. Repko
An estimate of the branching ratio for Z -> nu nubar gamma gamma
Three pages, 2 figures
null
10.1103/PhysRevD.86.097302
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The effective interaction for two neutrino, two photon coupling is used to find an approximate width for the decay of the Z boson into the nu nubar gamma gamma final state.
[ { "created": "Mon, 6 Aug 2012 14:52:39 GMT", "version": "v1" } ]
2013-05-30
[ [ "Dicus", "Duane A.", "" ], [ "Repko", "Wayne W.", "" ] ]
The effective interaction for two neutrino, two photon coupling is used to find an approximate width for the decay of the Z boson into the nu nubar gamma gamma final state.
hep-ph/0106130
Johan Bijnens
Johan Bijnens and Fredrik Persson (Lund)
Effects of different Form-factors in Meson-Photon-Photon Transitions and the Muon Anomalous Magnetic Moment
28p. Master thesis from december 1999 but the results were felt useful for the muon g-2 discussion. Version with more references in preparation
null
null
LU TP 99--39
hep-ph
null
The exact form of the form-factor associated with a meson-photon-photon vertex is not known. Different suggestions exist, based on constraints from QCD and on recent experiments. Four different form-factors are studied in this article. We calculate decay rates for the decays $\pi^{0}\to \gamma\gamma$, $\eta\to \gamma e^{+}e^{-}$, $\eta\to \mu^{+}\mu^{-} e^{+}e^{-}$} and $\eta\to e^{+}e^{-} e^{+}e^{-}$ and cross sections for the processes $e^{+}e^{-}\to PS e^{+}e^{-}$, where $PS=\pi^{0}$, $\eta$ or $\eta'$. The results depend on the choice of form-factor and we examine if the differences are large enough to distinguish in upcoming experiments. The dominant part of the light-by-light contribution to the muon anomalous magnetic moment is also calculated. Here the uncertainty around the choice of form-factor implies that it is possible to estimate a smallest error in the theoretical value of this contribution.
[ { "created": "Wed, 13 Jun 2001 07:02:52 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bijnens", "Johan", "", "Lund" ], [ "Persson", "Fredrik", "", "Lund" ] ]
The exact form of the form-factor associated with a meson-photon-photon vertex is not known. Different suggestions exist, based on constraints from QCD and on recent experiments. Four different form-factors are studied in this article. We calculate decay rates for the decays $\pi^{0}\to \gamma\gamma$, $\eta\to \gamma e^{+}e^{-}$, $\eta\to \mu^{+}\mu^{-} e^{+}e^{-}$} and $\eta\to e^{+}e^{-} e^{+}e^{-}$ and cross sections for the processes $e^{+}e^{-}\to PS e^{+}e^{-}$, where $PS=\pi^{0}$, $\eta$ or $\eta'$. The results depend on the choice of form-factor and we examine if the differences are large enough to distinguish in upcoming experiments. The dominant part of the light-by-light contribution to the muon anomalous magnetic moment is also calculated. Here the uncertainty around the choice of form-factor implies that it is possible to estimate a smallest error in the theoretical value of this contribution.
2306.09510
Pierluca Carenza
Pierluca Carenza, Tassia Ferreira, Roman Pasechnik, Zhi-Wei Wang
Glueball dark matter, precisely
12 pages, 6 figures; update and generalization of arXiv:2207.13716. v2: 12 pages, 6 figures; minor changes to match the published version
Phys.Rev.D 108 (2023) 12, 123027
10.1103/PhysRevD.108.123027
null
hep-ph astro-ph.CO hep-lat hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We delve deeper into the potential composition of dark matter as stable scalar glueballs from a confining dark $SU(N)$ gauge theory, focusing on $N=\{3,4,5\}$. To predict the relic abundance of glueballs for the various gauge groups and scenarios of thermalization of the dark gluon gas, we employ a thermal effective theory that accounts for the strong-coupling dynamics in agreement with lattice simulations. We compare our methodology with previous works and discuss the possible sources of discrepancy. The results are encouraging and show that glueballs can account for the totality of dark matter in many unconstrained scenarios with a phase transition scale $20$ MeV$\lesssim\Lambda\lesssim10^{10}$ GeV, thus opening the possibility of exciting future studies.
[ { "created": "Thu, 15 Jun 2023 21:14:37 GMT", "version": "v1" }, { "created": "Tue, 19 Dec 2023 17:00:52 GMT", "version": "v2" } ]
2023-12-20
[ [ "Carenza", "Pierluca", "" ], [ "Ferreira", "Tassia", "" ], [ "Pasechnik", "Roman", "" ], [ "Wang", "Zhi-Wei", "" ] ]
We delve deeper into the potential composition of dark matter as stable scalar glueballs from a confining dark $SU(N)$ gauge theory, focusing on $N=\{3,4,5\}$. To predict the relic abundance of glueballs for the various gauge groups and scenarios of thermalization of the dark gluon gas, we employ a thermal effective theory that accounts for the strong-coupling dynamics in agreement with lattice simulations. We compare our methodology with previous works and discuss the possible sources of discrepancy. The results are encouraging and show that glueballs can account for the totality of dark matter in many unconstrained scenarios with a phase transition scale $20$ MeV$\lesssim\Lambda\lesssim10^{10}$ GeV, thus opening the possibility of exciting future studies.
1001.0070
Xu Qing-Jun
Qing-Jun Xu, Z. was
News on PHOTOS Monte Carlo: gamma^* -> pi^+ pi^-(gamma) and K^\pm -> pi^+ pi^- e^\pm nu (gamma)
6 pages, 11 figures, proceedings of the PhiPsi09, Oct. 13-16, 2009, Beijing, China
Chin.Phys.C34:889-895,2010
10.1088/1674-1137/34/6/046
IFJPAN-IV-2010-1
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
PHOTOS Monte Carlo is widely used for simulating QED effects in decay of intermediate particles and resonances. It can be easily connected to other main process generators. In this paper we consider decaying processes gamma^* -> pi^+ pi^-(gamma) and K^\pm -> pi^+ pi^- e^\pm nu (gamma) in the framework of Scalar QED. These two processes are interesting not only for the technical aspect of PHOTOS Monte Carlo, but also for precision measurement of alpha_{QED}(M_Z), g-2, as well as pi pi scattering lengths.
[ { "created": "Mon, 4 Jan 2010 15:50:15 GMT", "version": "v1" }, { "created": "Wed, 13 Jan 2010 16:41:03 GMT", "version": "v2" }, { "created": "Thu, 14 Jan 2010 10:34:23 GMT", "version": "v3" } ]
2011-01-05
[ [ "Xu", "Qing-Jun", "" ], [ "was", "Z.", "" ] ]
PHOTOS Monte Carlo is widely used for simulating QED effects in decay of intermediate particles and resonances. It can be easily connected to other main process generators. In this paper we consider decaying processes gamma^* -> pi^+ pi^-(gamma) and K^\pm -> pi^+ pi^- e^\pm nu (gamma) in the framework of Scalar QED. These two processes are interesting not only for the technical aspect of PHOTOS Monte Carlo, but also for precision measurement of alpha_{QED}(M_Z), g-2, as well as pi pi scattering lengths.
0906.1757
Shun Zhou
Zhi-zhong Xing and Shun Zhou
Multiple seesaw mechanisms of neutrino masses at the TeV scale
10 pages, 2 figures, accepted for publication in Phys. Lett. B
Phys.Lett.B679:249-254,2009
10.1016/j.physletb.2009.07.051
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In pursuit of a balance between theoretical naturalness and experimental testability, we propose two classes of multiple seesaw mechanisms at the TeV scale to understand the origin of tiny neutrino masses. They are novel extensions of the canonical and double seesaw mechanisms, respectively, by introducing even and odd numbers of gauge-singlet fermions and scalars. It is thanks to a proper implementation of the global U(1)xZ_2N symmetry that the overall neutrino mass matrix in either class has a suggestive nearest-neighbor-interaction pattern. We briefly discuss possible consequences of these TeV-scale seesaw scenarios, which can hopefully be explored in the upcoming Large Hadron Collider and precision neutrino experiments, and present a simple but instructive example of model building.
[ { "created": "Tue, 9 Jun 2009 15:04:15 GMT", "version": "v1" }, { "created": "Thu, 23 Jul 2009 13:06:31 GMT", "version": "v2" } ]
2009-09-28
[ [ "Xing", "Zhi-zhong", "" ], [ "Zhou", "Shun", "" ] ]
In pursuit of a balance between theoretical naturalness and experimental testability, we propose two classes of multiple seesaw mechanisms at the TeV scale to understand the origin of tiny neutrino masses. They are novel extensions of the canonical and double seesaw mechanisms, respectively, by introducing even and odd numbers of gauge-singlet fermions and scalars. It is thanks to a proper implementation of the global U(1)xZ_2N symmetry that the overall neutrino mass matrix in either class has a suggestive nearest-neighbor-interaction pattern. We briefly discuss possible consequences of these TeV-scale seesaw scenarios, which can hopefully be explored in the upcoming Large Hadron Collider and precision neutrino experiments, and present a simple but instructive example of model building.
1905.05648
Krzysztof Rolbiecki
Jong Soo Kim, Stefan Pokorski, Krzysztof Rolbiecki and Kazuki Sakurai
Gravitino vs Neutralino LSP at the LHC
22 pages, 5 figures, minor changes, to appear in JHEP
null
10.1007/JHEP09(2019)082
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using the latest LHC data, we analyse and compare the lower limits on the masses of gluinos and the lightest stop in two natural supersymmetric motivated scenarios: one with a neutralino being the lightest supersymmetric particle (LSP) and the other one with gravitino as the LSP and neutralino as the next-to-lightest supersymmetric particle. In the second case our analysis applies to neutralinos promptly decaying to very light gravitinos, which are of cosmological interest, and are generic for low, of order O(100) TeV, messenger scale in gauge mediation models. We find that the lower bounds on the gluino and the lightest stop masses are stronger for the gravitino LSP scenarios due to the extra handle from the decay products of neutralinos. Generally, in contrast to the neutralino LSP case the limits now extend to a region of compressed spectrum. In bino scenarios the highest excluded stop mass increases from 1000 GeV to almost 1400 GeV. Additionally, in the higgsino-like NLSP scenario the higgsinos below 650 GeV are universally excluded and the stop mass limit is $m_{\tilde{t}} > 1150$ GeV, whereas there is no limit on stops in the higgsino LSP model for $m_{\tilde{h}} = 650$ GeV. Nevertheless, we find that the low messenger scale still ameliorates the fine tuning in the electroweak potential.
[ { "created": "Tue, 14 May 2019 14:45:55 GMT", "version": "v1" }, { "created": "Mon, 19 Aug 2019 15:39:15 GMT", "version": "v2" } ]
2019-10-02
[ [ "Kim", "Jong Soo", "" ], [ "Pokorski", "Stefan", "" ], [ "Rolbiecki", "Krzysztof", "" ], [ "Sakurai", "Kazuki", "" ] ]
Using the latest LHC data, we analyse and compare the lower limits on the masses of gluinos and the lightest stop in two natural supersymmetric motivated scenarios: one with a neutralino being the lightest supersymmetric particle (LSP) and the other one with gravitino as the LSP and neutralino as the next-to-lightest supersymmetric particle. In the second case our analysis applies to neutralinos promptly decaying to very light gravitinos, which are of cosmological interest, and are generic for low, of order O(100) TeV, messenger scale in gauge mediation models. We find that the lower bounds on the gluino and the lightest stop masses are stronger for the gravitino LSP scenarios due to the extra handle from the decay products of neutralinos. Generally, in contrast to the neutralino LSP case the limits now extend to a region of compressed spectrum. In bino scenarios the highest excluded stop mass increases from 1000 GeV to almost 1400 GeV. Additionally, in the higgsino-like NLSP scenario the higgsinos below 650 GeV are universally excluded and the stop mass limit is $m_{\tilde{t}} > 1150$ GeV, whereas there is no limit on stops in the higgsino LSP model for $m_{\tilde{h}} = 650$ GeV. Nevertheless, we find that the low messenger scale still ameliorates the fine tuning in the electroweak potential.
1607.06197
Zhen Fang
Zhen Fang
A holographic model for the baryon octet
6 pages
Phys. Rev. D 94, 074017 (2016)
10.1103/PhysRevD.94.074017
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
By adopting the nonlinear realization of chiral symmetry, a holographic model for the baryon octet is proposed. The mass spectra of the baryon octet and their low-lying excited states are calculated, which show good consistency with experiments. The couplings of pion to nucleons are derived in two gauges and are shown to be equivalent with each other. It also shows that only derivative couplings of pion to nucleons appear in this holographic model. The coupling constant is then calculated.
[ { "created": "Thu, 21 Jul 2016 05:24:42 GMT", "version": "v1" } ]
2016-10-19
[ [ "Fang", "Zhen", "" ] ]
By adopting the nonlinear realization of chiral symmetry, a holographic model for the baryon octet is proposed. The mass spectra of the baryon octet and their low-lying excited states are calculated, which show good consistency with experiments. The couplings of pion to nucleons are derived in two gauges and are shown to be equivalent with each other. It also shows that only derivative couplings of pion to nucleons appear in this holographic model. The coupling constant is then calculated.
1201.0809
Kevin Engel
Kevin T. Engel, Hiren H. Patel, Michael J. Ramsey-Musolf
Hadronic Light-by-Light and the Pion Polarizability
4 pages, 1 figure
null
10.1103/PhysRevD.86.037502
NPAC-11-16; CALT 68-2861
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the charged pion loop contribution to the light-by-light scattering amplitude for off-shell photons in chiral perturbation theory through next-to-leading order (NLO). We show that NLO contributions are relatively more important due to a fortuitous numerical suppression of the leading-order (LO) terms. Consequently, one expects theoretical predictions for the hadronic light-by-light (HLBL) contribution to the muon anomalous magnetic moment, $a_\mu^{HLBL}$, to be sensitive to the choice of model for the higher momentum-dependence of the LBL amplitude. We show that models employed thus far for the charged pion loop contribution to $a_\mu^{HLBL}$ are not consistent with low-momentum behavior implied by quantum chromodynamics, having omitted potentially significant contributions from the pion polarizability.
[ { "created": "Wed, 4 Jan 2012 02:45:42 GMT", "version": "v1" }, { "created": "Fri, 13 Jan 2012 20:40:59 GMT", "version": "v2" } ]
2013-05-30
[ [ "Engel", "Kevin T.", "" ], [ "Patel", "Hiren H.", "" ], [ "Ramsey-Musolf", "Michael J.", "" ] ]
We compute the charged pion loop contribution to the light-by-light scattering amplitude for off-shell photons in chiral perturbation theory through next-to-leading order (NLO). We show that NLO contributions are relatively more important due to a fortuitous numerical suppression of the leading-order (LO) terms. Consequently, one expects theoretical predictions for the hadronic light-by-light (HLBL) contribution to the muon anomalous magnetic moment, $a_\mu^{HLBL}$, to be sensitive to the choice of model for the higher momentum-dependence of the LBL amplitude. We show that models employed thus far for the charged pion loop contribution to $a_\mu^{HLBL}$ are not consistent with low-momentum behavior implied by quantum chromodynamics, having omitted potentially significant contributions from the pion polarizability.
hep-ph/9305208
Jihn E. Kim
Eung Jin Chun, Hang Bae Kim and Jihn E. Kim
Dark Matters in Axino Gravitino Cosmology
9 pages, Latex
Phys.Rev.Lett.72:1956-1959,1994
10.1103/PhysRevLett.72.1956
null
hep-ph
null
It is suggested that the axino mass in the 1 MeV region and gravitino mass in the eV region can provide an axino lifetime of order of the time of photon decoupling. In this case, some undecayed axinos act like cold dark matters and some axino decay products (gravitinos and hot axions) act like hot dark matters at the time of galaxy formation.
[ { "created": "Tue, 4 May 1993 11:49:18 GMT", "version": "v1" } ]
2010-12-09
[ [ "Chun", "Eung Jin", "" ], [ "Kim", "Hang Bae", "" ], [ "Kim", "Jihn E.", "" ] ]
It is suggested that the axino mass in the 1 MeV region and gravitino mass in the eV region can provide an axino lifetime of order of the time of photon decoupling. In this case, some undecayed axinos act like cold dark matters and some axino decay products (gravitinos and hot axions) act like hot dark matters at the time of galaxy formation.
2108.11381
Yu-Pan Zeng
Yu-Pan Zeng and Xiang Xiao and Wei Wang
Constraints on Pseudo-Nambu-Goldstone dark matter from direct detection experiment and neutron star reheating temperature
9 pages, 2 figures
Physics Letters B 824 (2022) 136822
10.1016/j.physletb.2021.136822
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Pseudo-Nambu-Goldstone dark matter connected to Standard Model fermion through the Higgs portal has the property that its direct detection vanishes in the zero momentum transfer limit due to a cancellation mechanism. This feature helps the Pseudo-Nambu-Goldstone dark matter to escape the stringent constraints from direct detection experiments. In this paper we explore new constraints on parameter space of non-zero momentum transfer from the direct detection experiments, and also from the neutron star temperature via the dark matter reheating mechanism.
[ { "created": "Wed, 25 Aug 2021 15:48:31 GMT", "version": "v1" }, { "created": "Tue, 19 Oct 2021 16:59:27 GMT", "version": "v2" }, { "created": "Wed, 8 Dec 2021 01:50:00 GMT", "version": "v3" } ]
2021-12-09
[ [ "Zeng", "Yu-Pan", "" ], [ "Xiao", "Xiang", "" ], [ "Wang", "Wei", "" ] ]
Pseudo-Nambu-Goldstone dark matter connected to Standard Model fermion through the Higgs portal has the property that its direct detection vanishes in the zero momentum transfer limit due to a cancellation mechanism. This feature helps the Pseudo-Nambu-Goldstone dark matter to escape the stringent constraints from direct detection experiments. In this paper we explore new constraints on parameter space of non-zero momentum transfer from the direct detection experiments, and also from the neutron star temperature via the dark matter reheating mechanism.
2303.13937
Knut Zoch
Lukas Ehrke, John Andrew Raine, Knut Zoch, Manuel Guth, Tobias Golling
Topological Reconstruction of Particle Physics Processes using Graph Neural Networks
25 pages, 24 figures, 8 tables
Phys. Rev. D 107 (2023) 116019
10.1103/PhysRevD.107.116019
null
hep-ph cs.LG hep-ex
http://creativecommons.org/licenses/by/4.0/
We present a new approach, the Topograph, which reconstructs underlying physics processes, including the intermediary particles, by leveraging underlying priors from the nature of particle physics decays and the flexibility of message passing graph neural networks. The Topograph not only solves the combinatoric assignment of observed final state objects, associating them to their original mother particles, but directly predicts the properties of intermediate particles in hard scatter processes and their subsequent decays. In comparison to standard combinatoric approaches or modern approaches using graph neural networks, which scale exponentially or quadratically, the complexity of Topographs scales linearly with the number of reconstructed objects. We apply Topographs to top quark pair production in the all hadronic decay channel, where we outperform the standard approach and match the performance of the state-of-the-art machine learning technique.
[ { "created": "Fri, 24 Mar 2023 11:50:08 GMT", "version": "v1" }, { "created": "Mon, 27 Mar 2023 14:27:45 GMT", "version": "v2" }, { "created": "Fri, 28 Apr 2023 16:09:32 GMT", "version": "v3" }, { "created": "Wed, 17 May 2023 14:15:06 GMT", "version": "v4" }, { "created": "Fri, 13 Oct 2023 06:43:44 GMT", "version": "v5" } ]
2023-10-16
[ [ "Ehrke", "Lukas", "" ], [ "Raine", "John Andrew", "" ], [ "Zoch", "Knut", "" ], [ "Guth", "Manuel", "" ], [ "Golling", "Tobias", "" ] ]
We present a new approach, the Topograph, which reconstructs underlying physics processes, including the intermediary particles, by leveraging underlying priors from the nature of particle physics decays and the flexibility of message passing graph neural networks. The Topograph not only solves the combinatoric assignment of observed final state objects, associating them to their original mother particles, but directly predicts the properties of intermediate particles in hard scatter processes and their subsequent decays. In comparison to standard combinatoric approaches or modern approaches using graph neural networks, which scale exponentially or quadratically, the complexity of Topographs scales linearly with the number of reconstructed objects. We apply Topographs to top quark pair production in the all hadronic decay channel, where we outperform the standard approach and match the performance of the state-of-the-art machine learning technique.
hep-ph/0601229
Joan Rojo
Joan Rojo
Neural network parametrization of the lepton energy spectrum in semileptonic B meson decays
32 pages, 22 figures, JHEP3 class. v4 version accepted for publication in JHEP
JHEP 0605:040,2006
10.1088/1126-6708/2006/05/040
null
hep-ph hep-ex
null
We construct a parametrization of the lepton energy spectrum in inclusive semileptonic decays of B mesons, based on the available experimental information: moments of the spectrum with cuts, their errors and their correlations, together with kinematical constraints. The result is obtained in the form of a Monte Carlo sample of neural networks trained on replicas of the experimental data, which represents the probability density in the space of lepton energy spectra. This parametrization is then used to extract the b quark mass m_b^{1S} in a way that theoretical uncertainties are minimized, for which the value m_b^{1S}=4.84 \pm 0.14^{exp}\pm 0.05^{th} GeV is obtained.
[ { "created": "Fri, 27 Jan 2006 11:16:21 GMT", "version": "v1" }, { "created": "Tue, 31 Jan 2006 08:01:12 GMT", "version": "v2" }, { "created": "Tue, 7 Feb 2006 08:28:58 GMT", "version": "v3" }, { "created": "Mon, 15 May 2006 08:56:25 GMT", "version": "v4" } ]
2011-01-25
[ [ "Rojo", "Joan", "" ] ]
We construct a parametrization of the lepton energy spectrum in inclusive semileptonic decays of B mesons, based on the available experimental information: moments of the spectrum with cuts, their errors and their correlations, together with kinematical constraints. The result is obtained in the form of a Monte Carlo sample of neural networks trained on replicas of the experimental data, which represents the probability density in the space of lepton energy spectra. This parametrization is then used to extract the b quark mass m_b^{1S} in a way that theoretical uncertainties are minimized, for which the value m_b^{1S}=4.84 \pm 0.14^{exp}\pm 0.05^{th} GeV is obtained.