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1904.02560
Leandro Da Rold
Leandro Da Rold (1 and 2) and Alejo N. Rossia (2 and 3) ((1) CONICET, (2) Instituto Balseiro, (3) DESY)
The Minimal Simple Composite Higgs Model
39 pages, 9 figures, v2, published version, we have added discussions concerning the lightest state and a new representation for fermions, references added
null
10.1007/JHEP12(2019)023
DESY 19-005
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Most of the analysis of composite Higgs have focussed on the Minimal Composite Higgs Model, based on the coset SO(5)$\times$U(1)$_X$/SO(4)$\times$U(1)$_X$. We consider a model based on the coset of simple groups SO(7)/SO(6), with SO(4)$\times$U(1)$_X$ embedded into SO(6). This extension of the minimal model leads to a new complex pNGB that has hypercharge and is a singlet of SU(2)$_L$, with properties mostly determined by the pattern of symmetry breaking and a mass of order TeV. Composite electroweak unification also leads to new bosonic and fermion resonances with exotic charges, not present in the minimal model. The lightest of these resonances is stable, and in some cases could provide candidates for dark matter. A new rich phenomenology is expected at LHC.
[ { "created": "Thu, 4 Apr 2019 14:04:42 GMT", "version": "v1" }, { "created": "Wed, 13 Nov 2019 19:32:45 GMT", "version": "v2" } ]
2020-01-29
[ [ "Da Rold", "Leandro", "", "1 and 2" ], [ "Rossia", "Alejo N.", "", "2 and 3" ] ]
Most of the analysis of composite Higgs have focussed on the Minimal Composite Higgs Model, based on the coset SO(5)$\times$U(1)$_X$/SO(4)$\times$U(1)$_X$. We consider a model based on the coset of simple groups SO(7)/SO(6), with SO(4)$\times$U(1)$_X$ embedded into SO(6). This extension of the minimal model leads to a new complex pNGB that has hypercharge and is a singlet of SU(2)$_L$, with properties mostly determined by the pattern of symmetry breaking and a mass of order TeV. Composite electroweak unification also leads to new bosonic and fermion resonances with exotic charges, not present in the minimal model. The lightest of these resonances is stable, and in some cases could provide candidates for dark matter. A new rich phenomenology is expected at LHC.
hep-ph/0606016
George W. S. Hou
Wei-Shu Hou
Searching for the Bottom Counterparts of X(3872) and Y(4260) via $\pi^+\pi^-\Upsilon$
4 pages, no figures, version to appear in PRD; expanded, including comments on LHCb
Phys.Rev.D74:017504,2006
10.1103/PhysRevD.74.017504
null
hep-ph
null
The X(3872) and Y(4260), among a host of charmonium-like mesons, have rather unusual properties: the former has very small total width, the latter has large rate into $\pi^+\pi^-J/\psi$ channel. It would not be easy to settle between the many suggested explanations for their composition. We point out that discovering the bottom counterparts should shed much light on the issue. The narrow state can be searched for at the Tevatron via $p\bar p \to \pi^+\pi^-\Upsilon + X$, but the LHC should be much more promising. The state with large overlap with $\Upsilon$ can be searched for at B factories via radiative return $e^+e^- \to \gamma_{\rm ISR} + \pi^+\pi^-\Upsilon$ on $\Upsilon(5S)$, or by $e^+e^- \to \pi^+\pi^-\Upsilon$ direct scan.
[ { "created": "Thu, 1 Jun 2006 16:29:48 GMT", "version": "v1" }, { "created": "Fri, 21 Jul 2006 08:02:25 GMT", "version": "v2" } ]
2008-11-26
[ [ "Hou", "Wei-Shu", "" ] ]
The X(3872) and Y(4260), among a host of charmonium-like mesons, have rather unusual properties: the former has very small total width, the latter has large rate into $\pi^+\pi^-J/\psi$ channel. It would not be easy to settle between the many suggested explanations for their composition. We point out that discovering the bottom counterparts should shed much light on the issue. The narrow state can be searched for at the Tevatron via $p\bar p \to \pi^+\pi^-\Upsilon + X$, but the LHC should be much more promising. The state with large overlap with $\Upsilon$ can be searched for at B factories via radiative return $e^+e^- \to \gamma_{\rm ISR} + \pi^+\pi^-\Upsilon$ on $\Upsilon(5S)$, or by $e^+e^- \to \pi^+\pi^-\Upsilon$ direct scan.
1608.00454
Reza Khosravi
S. Momeni and R. Khosravi
FCNC transition of $B$ to $a_1$ with LCSR
20 pages, 6 figures
Phys. Rev. D 95, 016009 (2017)
10.1103/PhysRevD.95.016009
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $B\to a_1 \ell^+ \ell^-$ decays occur by the electroweak penguin and box diagrams which can be performed through the flavor changing neutral current (FCNC). We calculate the form factors of the FCNC $B \to a_1$ transitions in the light--cone sum rules approach, up to twist--4 distribution amplitudes of the axial vector meson $a_1$. Forward--backward asymmetry, as well as branching ratios of $B\to a_1\ell^{+}\ell^{-}$, and $B\to a_1 \gamma$ decays are considered. A comparison is also made between our results and the predictions of other methods.
[ { "created": "Mon, 1 Aug 2016 14:47:16 GMT", "version": "v1" }, { "created": "Thu, 4 Aug 2016 08:05:18 GMT", "version": "v2" } ]
2017-02-08
[ [ "Momeni", "S.", "" ], [ "Khosravi", "R.", "" ] ]
The $B\to a_1 \ell^+ \ell^-$ decays occur by the electroweak penguin and box diagrams which can be performed through the flavor changing neutral current (FCNC). We calculate the form factors of the FCNC $B \to a_1$ transitions in the light--cone sum rules approach, up to twist--4 distribution amplitudes of the axial vector meson $a_1$. Forward--backward asymmetry, as well as branching ratios of $B\to a_1\ell^{+}\ell^{-}$, and $B\to a_1 \gamma$ decays are considered. A comparison is also made between our results and the predictions of other methods.
0705.1920
Peihong Gu
Pei-Hong Gu, Utpal Sarkar
Leptogenesis, Dark Matter and Higgs Phenomenology at TeV
7 pages, 3 figures. References added. Accepted by NPB
Nucl.Phys.B789:245-257,2008
10.1016/j.nuclphysb.2007.08.004
null
hep-ph
null
We propose an interesting model of neutrino masses to realize leptogenesis and dark matter at the TeV scale. A real scalar is introduced to naturally realize the Majorana masses of the right-handed neutrinos. We also include a new Higgs doublet that contributes to the dark matter of the universe. The neutrino masses come from the vacuum expectation value of the triplet Higgs scalar. The right-handed neutrinos are not constrained by the neutrino masses and hence they could generate leptogenesis at the TeV scale without subscribing to resonant leptogenesis. In our model, all new particles could be observable at the forthcoming Large Hardon Collider or the proposed future International Linear Collider.
[ { "created": "Mon, 14 May 2007 12:03:44 GMT", "version": "v1" }, { "created": "Mon, 21 May 2007 09:18:49 GMT", "version": "v2" }, { "created": "Wed, 15 Aug 2007 08:13:45 GMT", "version": "v3" } ]
2008-11-26
[ [ "Gu", "Pei-Hong", "" ], [ "Sarkar", "Utpal", "" ] ]
We propose an interesting model of neutrino masses to realize leptogenesis and dark matter at the TeV scale. A real scalar is introduced to naturally realize the Majorana masses of the right-handed neutrinos. We also include a new Higgs doublet that contributes to the dark matter of the universe. The neutrino masses come from the vacuum expectation value of the triplet Higgs scalar. The right-handed neutrinos are not constrained by the neutrino masses and hence they could generate leptogenesis at the TeV scale without subscribing to resonant leptogenesis. In our model, all new particles could be observable at the forthcoming Large Hardon Collider or the proposed future International Linear Collider.
hep-ph/0101238
Oleg Selugin
S.B. Nurushev, O.V. Selyugin, M.N.Strikhanov
Coulomb-hadron phase factor and spin phenomena in a wide region of transfer momenta
9 pages, LaTeX, 4 figures
Czech.J.Phys. 50S1 (2000) 193-200
10.1007/s10582-000-0025-x
null
hep-ph
null
The Coulomb-hadron interference effects are examined at small and large $t$. The methods for the definition of spin-dependent parts of hadron scattering amplitude are presented. The additional contributions to analyzing power $A_N$ and the double spin correlation parameter $A_{NN}$ owing to the electromagnetic-hadron interference are determined in the diffraction dip domain of high-energy elastic hadron scattering.
[ { "created": "Mon, 22 Jan 2001 09:45:56 GMT", "version": "v1" } ]
2017-08-23
[ [ "Nurushev", "S. B.", "" ], [ "Selyugin", "O. V.", "" ], [ "Strikhanov", "M. N.", "" ] ]
The Coulomb-hadron interference effects are examined at small and large $t$. The methods for the definition of spin-dependent parts of hadron scattering amplitude are presented. The additional contributions to analyzing power $A_N$ and the double spin correlation parameter $A_{NN}$ owing to the electromagnetic-hadron interference are determined in the diffraction dip domain of high-energy elastic hadron scattering.
hep-ph/0112206
Joydip Kundu
Joydip Kundu (MIT), Krishna Rajagopal (MIT)
Mass-Induced Crystalline Color Superconductivity
12 pages, 4 figures. v2: very small change only
Phys.Rev. D65 (2002) 094022
10.1103/PhysRevD.65.094022
MIT-CTP-3224
hep-ph nucl-th
null
We demonstrate that crystalline color superconductivity may arise as a result of pairing between massless quarks and quarks with nonzero mass m_s. Previous analyses of this phase of cold dense quark matter have all utilized a chemical potential difference \delta\mu to favor crystalline color superconductivity over ordinary BCS pairing. In any context in which crystalline color superconductivity occurs in nature, however, it will be m_s-induced. The effect of m_s is qualitatively different from that of \delta\mu in one crucial respect: m_s depresses the value of the BCS gap \Delta_0 whereas \delta\mu leaves \Delta_0 unchanged. This effect in the BCS phase must be taken into account before m_s-induced and \delta\mu-induced crystalline color superconductivity can sensibly be compared.
[ { "created": "Fri, 14 Dec 2001 20:10:35 GMT", "version": "v1" }, { "created": "Wed, 9 Jan 2002 20:16:24 GMT", "version": "v2" } ]
2009-11-07
[ [ "Kundu", "Joydip", "", "MIT" ], [ "Rajagopal", "Krishna", "", "MIT" ] ]
We demonstrate that crystalline color superconductivity may arise as a result of pairing between massless quarks and quarks with nonzero mass m_s. Previous analyses of this phase of cold dense quark matter have all utilized a chemical potential difference \delta\mu to favor crystalline color superconductivity over ordinary BCS pairing. In any context in which crystalline color superconductivity occurs in nature, however, it will be m_s-induced. The effect of m_s is qualitatively different from that of \delta\mu in one crucial respect: m_s depresses the value of the BCS gap \Delta_0 whereas \delta\mu leaves \Delta_0 unchanged. This effect in the BCS phase must be taken into account before m_s-induced and \delta\mu-induced crystalline color superconductivity can sensibly be compared.
1003.1223
Mikhail Braun
M.A.Braun
BKP states in the inclusive gluon production
30 pages, 17 figures. Appendix with a new observation added. Conclusions changed.
Eur.Phys.J.C70:73-90,2010
10.1140/epjc/s10052-010-1469-1
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inclusive cross-section for gluon production is calculated by the dispersion technique in the NLO in the perturbative QCD with a large number of colours. The found cross-section coincides with the one derived in the dipole picture. No trace of the BKP states is found.
[ { "created": "Fri, 5 Mar 2010 10:08:43 GMT", "version": "v1" }, { "created": "Sat, 6 Mar 2010 07:33:15 GMT", "version": "v2" }, { "created": "Fri, 26 Mar 2010 04:34:21 GMT", "version": "v3" } ]
2011-02-09
[ [ "Braun", "M. A.", "" ] ]
Inclusive cross-section for gluon production is calculated by the dispersion technique in the NLO in the perturbative QCD with a large number of colours. The found cross-section coincides with the one derived in the dipole picture. No trace of the BKP states is found.
hep-ph/9704342
Robert Peschanski
R.Peschanski
Dual Shapiro-Virasoro amplitudes in the QCD dipole picture
4 (1.tex, 3.ps) files: text (tex), tables, 2 figures
Phys.Lett.B409:491-498,1997
10.1016/S0370-2693(97)00926-X
T 97/034 (SPhT, Saclay)
hep-ph hep-th
null
Using the QCD dipole picture of BFKL dynamics and the conformal invariance properties of the BFKL kernel in transverse coordinate space, we show that the 1--to--p dipole densities can be expressed in terms of dual Shapiro- Virasoro amplitudes B{2p+2} and their generalization including non-zero conformal spins. We discuss the possibility of an effective closed string theory of interacting QCD dipoles.
[ { "created": "Thu, 17 Apr 1997 08:20:31 GMT", "version": "v1" } ]
2008-11-26
[ [ "Peschanski", "R.", "" ] ]
Using the QCD dipole picture of BFKL dynamics and the conformal invariance properties of the BFKL kernel in transverse coordinate space, we show that the 1--to--p dipole densities can be expressed in terms of dual Shapiro- Virasoro amplitudes B{2p+2} and their generalization including non-zero conformal spins. We discuss the possibility of an effective closed string theory of interacting QCD dipoles.
hep-ph/9602425
G. B. Pivovarov
Grigirii Pivovarov (Inst. for Nucl. Res., Moscow)
Gauge Dependence of Four-Fermion QED Green Function and a Breakdown of Gauge Invariance in Atom-Like Bound State Calculations
11 pages, LaTex, no figures, to appear in Nucl. Phys. B
Nucl.Phys. B466 (1996) 159-172
10.1016/0550-3213(96)00093-4
INR--917/96
hep-ph
null
We derive a relation between four-fermion QED Green functions of different covariant gauges which defines the gauge dependence completely. We use the derived gauge dependence to check the gauge invariance of atom-like bound state calculations. We find that the existing QED procedure does not provide gauge invariant binding energies. A way to a corrected gauge invariant procedure is pointed out.
[ { "created": "Thu, 29 Feb 1996 07:46:45 GMT", "version": "v1" } ]
2009-10-28
[ [ "Pivovarov", "Grigirii", "", "Inst. for Nucl. Res., Moscow" ] ]
We derive a relation between four-fermion QED Green functions of different covariant gauges which defines the gauge dependence completely. We use the derived gauge dependence to check the gauge invariance of atom-like bound state calculations. We find that the existing QED procedure does not provide gauge invariant binding energies. A way to a corrected gauge invariant procedure is pointed out.
1110.4335
Sergio Pastor
Gianpiero Mangano, Gennaro Miele, Sergio Pastor, Ofelia Pisanti, Srdjan Sarikas
Updated BBN bounds on the cosmological lepton asymmetry for non-zero theta13
16 pages, 5 figures
Phys. Lett. B 708 (2012) 1-5
10.1016/j.physletb.2012.01.015
IFIC/11-58, DSF-13-2011
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the bounds on the cosmological lepton number from Big Bang Nucleosynthesis (BBN), in light of recent evidences for a large value of the neutrino mixing angle theta13. The largest asymmetries for electron and muon or tau neutrinos compatible with 4He and 2H primordial yields are computed versus the neutrino mass hierarchy and mixing angles. The flavour oscillation dynamics is traced till the beginning of BBN and neutrino distributions after decoupling are numerically computed. The latter contains in general, non thermal distortion due to the onset of flavour oscillations driven by solar squared mass difference in the temperature range where neutrino scatterings become inefficient to enforce thermodynamical equilibrium. Depending on the value of theta13, this translates into a larger value for the effective number of neutrinos, N_eff. Upper bounds on this parameter are discussed for both neutrino mass hierarchies. Values for N_eff which are large enough to be detectable by the Planck experiment are found only for the (presently disfavoured) range sin^2(theta13)<0.01.
[ { "created": "Wed, 19 Oct 2011 16:53:20 GMT", "version": "v1" } ]
2012-02-01
[ [ "Mangano", "Gianpiero", "" ], [ "Miele", "Gennaro", "" ], [ "Pastor", "Sergio", "" ], [ "Pisanti", "Ofelia", "" ], [ "Sarikas", "Srdjan", "" ] ]
We discuss the bounds on the cosmological lepton number from Big Bang Nucleosynthesis (BBN), in light of recent evidences for a large value of the neutrino mixing angle theta13. The largest asymmetries for electron and muon or tau neutrinos compatible with 4He and 2H primordial yields are computed versus the neutrino mass hierarchy and mixing angles. The flavour oscillation dynamics is traced till the beginning of BBN and neutrino distributions after decoupling are numerically computed. The latter contains in general, non thermal distortion due to the onset of flavour oscillations driven by solar squared mass difference in the temperature range where neutrino scatterings become inefficient to enforce thermodynamical equilibrium. Depending on the value of theta13, this translates into a larger value for the effective number of neutrinos, N_eff. Upper bounds on this parameter are discussed for both neutrino mass hierarchies. Values for N_eff which are large enough to be detectable by the Planck experiment are found only for the (presently disfavoured) range sin^2(theta13)<0.01.
hep-ph/9710502
Chris Michael
Chris Michael
Hadron Spectroscopy from the Lattice
to appear in Proceedings of HADRON97, BNL, August 1997, edited S.-U. Chung, AIP press; 12 pages, Latex, uses aipproc.sty, 5 postscript figures
AIPConf.Proc.432:657-668,1998
10.1063/1.55976
LTH 415
hep-ph hep-lat
null
Lattice QCD determinations appropriate to hadron spectroscopy are reviewed with emphasis on the glueball and hybrid meson states in the quenched approximation. Hybrids are discussed for heavy and for light quarks. The effects of sea quarks (unquenching) are explored. Heavy-light systems are presented - particularly excited B mesons.
[ { "created": "Tue, 28 Oct 1997 12:03:01 GMT", "version": "v1" } ]
2009-10-30
[ [ "Michael", "Chris", "" ] ]
Lattice QCD determinations appropriate to hadron spectroscopy are reviewed with emphasis on the glueball and hybrid meson states in the quenched approximation. Hybrids are discussed for heavy and for light quarks. The effects of sea quarks (unquenching) are explored. Heavy-light systems are presented - particularly excited B mesons.
1709.10233
Zhuoran Huang
Zhuo-Ran Huang, Hong-Ying Jin, T.G. Steele and Zhu-Feng Zhang
The Mass and Decay Properties of the $1^{-+}$ Light Hybrid Meson
5 pages, 2 tables, 1 figure. Proceedings article for the 20th High-Energy Physics International Conference in Quantum Chromodynamics (QCD17) in Montpellier, France July 3-7 2017
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the complete form of the dimension-8 condensate contributions in the two-point correlator of the ($1^{-+}$,$0^{++}$) light hybrid current considering the operator mixing under renormalization. We find the inclusion these higher power corrections as well as the update of $\langle g^3G^3\rangle$ increase the QCD sum rule mass prediction for the $1^{-+}$ light hybrid. The obtained conservative mass range 1.72--2.60 GeV does not favor the $\pi_1(1400)$ and the $\pi_1(1600)$ to be pure hybrid states and suggests the $\pi_1(2015)$ observed by E852 is more likely to have much of a hybrid constituent. We also study the $b_1\pi$ and $\rho\pi$ decay patterns of the $1^{-+}$ light hybrid with light-cone QCD sum rules. We obtain a relatively large partial decay width of the $b_1\pi$ mode, which is consistent with the predictions from the flux tube models and lattice QCD. More interestingly, using the tensor interpolating current we find the partial decay width of the $\rho\pi$ mode is small due to the absence of the leading twist contribution in the light-cone expansion of the correlation function.
[ { "created": "Fri, 29 Sep 2017 04:23:42 GMT", "version": "v1" } ]
2017-10-02
[ [ "Huang", "Zhuo-Ran", "" ], [ "Jin", "Hong-Ying", "" ], [ "Steele", "T. G.", "" ], [ "Zhang", "Zhu-Feng", "" ] ]
We calculate the complete form of the dimension-8 condensate contributions in the two-point correlator of the ($1^{-+}$,$0^{++}$) light hybrid current considering the operator mixing under renormalization. We find the inclusion these higher power corrections as well as the update of $\langle g^3G^3\rangle$ increase the QCD sum rule mass prediction for the $1^{-+}$ light hybrid. The obtained conservative mass range 1.72--2.60 GeV does not favor the $\pi_1(1400)$ and the $\pi_1(1600)$ to be pure hybrid states and suggests the $\pi_1(2015)$ observed by E852 is more likely to have much of a hybrid constituent. We also study the $b_1\pi$ and $\rho\pi$ decay patterns of the $1^{-+}$ light hybrid with light-cone QCD sum rules. We obtain a relatively large partial decay width of the $b_1\pi$ mode, which is consistent with the predictions from the flux tube models and lattice QCD. More interestingly, using the tensor interpolating current we find the partial decay width of the $\rho\pi$ mode is small due to the absence of the leading twist contribution in the light-cone expansion of the correlation function.
0912.4785
Murugeswaran Duraisamy
Alakabha Datta, Murugeswaran Duraisamy
Model Independent Predictions for Rare Top Decays with Weak Coupling
14 pages, 4 figures. Accepted in PRD
Phys.Rev.D81:074008,2010
10.1103/PhysRevD.81.074008
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Measurements at B factories have provided important constraints on new physics in several rare processes involving the B meson. New Physics, if present in the b quark sector may also affect the top sector. In an effective Lagrangian approach, we write down operators where effects in the bottom and the top sector are related. Assuming the couplings of the operators to be of the same size as the weak coupling g of the Standard Model and taking into account constraints on new physics from the bottom sector as well as top branching ratios, we make predictions for the rare top decays t -> cV where V = \gamma, Z. We find branching fractions for these decays within possible reach of the LHC. Predictions are also made for t -> sW.
[ { "created": "Thu, 24 Dec 2009 04:32:20 GMT", "version": "v1" }, { "created": "Fri, 5 Mar 2010 04:27:41 GMT", "version": "v2" } ]
2010-04-23
[ [ "Datta", "Alakabha", "" ], [ "Duraisamy", "Murugeswaran", "" ] ]
Measurements at B factories have provided important constraints on new physics in several rare processes involving the B meson. New Physics, if present in the b quark sector may also affect the top sector. In an effective Lagrangian approach, we write down operators where effects in the bottom and the top sector are related. Assuming the couplings of the operators to be of the same size as the weak coupling g of the Standard Model and taking into account constraints on new physics from the bottom sector as well as top branching ratios, we make predictions for the rare top decays t -> cV where V = \gamma, Z. We find branching fractions for these decays within possible reach of the LHC. Predictions are also made for t -> sW.
1606.00951
Xiao-Gang He
Alper Hayreter, Xiao-Gang He, German Valencia
Yukawa sector for LFV in $h\to \mu\tau$ and CP violation in $h\to \tau\tau$
RevTex, 19 pages with two figures
Phys. Rev. D 94, 075002 (2016)
10.1103/PhysRevD.94.075002
CoEPP-MN-16-14
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Higgs boson discovered at the LHC opened a new chapter for particle physics. Its properties need to be studied in detail to distinguish a purely standard model (SM) Higgs boson from one of many scalars in an enlarged Higgs sector. The CMS collaboration has reported a possible lepton flavor violating (LFV) signal $h\to\mu\tau$, which if confirmed, implies that the Higgs sector is larger than in the SM. New physics responsible for this type of decay may, in general, also introduce other observable effects such as charge-parity (CP) violation in $h\to \tau\tau$. We study two types of models that single out the third generation and can induce large $h \to \mu\tau$ rates with different consequences for CP violation in $h \to \tau \tau$. Predictions for the size of the CP violating couplings require knowledge of the lepton Yukawa matrices and we discuss this in the context of two different textures considering all existing constraints.
[ { "created": "Fri, 3 Jun 2016 02:32:51 GMT", "version": "v1" } ]
2016-10-12
[ [ "Hayreter", "Alper", "" ], [ "He", "Xiao-Gang", "" ], [ "Valencia", "German", "" ] ]
The Higgs boson discovered at the LHC opened a new chapter for particle physics. Its properties need to be studied in detail to distinguish a purely standard model (SM) Higgs boson from one of many scalars in an enlarged Higgs sector. The CMS collaboration has reported a possible lepton flavor violating (LFV) signal $h\to\mu\tau$, which if confirmed, implies that the Higgs sector is larger than in the SM. New physics responsible for this type of decay may, in general, also introduce other observable effects such as charge-parity (CP) violation in $h\to \tau\tau$. We study two types of models that single out the third generation and can induce large $h \to \mu\tau$ rates with different consequences for CP violation in $h \to \tau \tau$. Predictions for the size of the CP violating couplings require knowledge of the lepton Yukawa matrices and we discuss this in the context of two different textures considering all existing constraints.
hep-ph/9907484
Lianshou Liu
Wang Qin, Li Zhiming and Liu Lianshou
Model Investigation of Non-Thermal Phase Transition in High Energy Collisions
8 pages 3 PS figures
Sci. China Ser. A43 (2000) 780-784
null
HZPP-9904
hep-ph
null
The Non-thermal phase transition in high energy collisions is studied in some detail in the framework of random cascade model. The relation between the characteristic parameter $\lambda_q$ of phase transition and the rank $q$ of moment is obtained using Monte Carlo simulation, and the existence of two phases in self-similarly cascading multiparticle systems is shown. The relation between the critical point $q_c$ of phase transition on the fluctuation parameter $\alpha$ is obtained and compared with the experimental results from NA22. The same study is carried out also by analytical calculation under central limit approximation. The range of validity of the central limit approximation is discussed.
[ { "created": "Mon, 26 Jul 1999 01:59:26 GMT", "version": "v1" } ]
2007-05-23
[ [ "Qin", "Wang", "" ], [ "Zhiming", "Li", "" ], [ "Lianshou", "Liu", "" ] ]
The Non-thermal phase transition in high energy collisions is studied in some detail in the framework of random cascade model. The relation between the characteristic parameter $\lambda_q$ of phase transition and the rank $q$ of moment is obtained using Monte Carlo simulation, and the existence of two phases in self-similarly cascading multiparticle systems is shown. The relation between the critical point $q_c$ of phase transition on the fluctuation parameter $\alpha$ is obtained and compared with the experimental results from NA22. The same study is carried out also by analytical calculation under central limit approximation. The range of validity of the central limit approximation is discussed.
1707.03837
Diptimoy Ghosh
Pritibhajan Byakti, Diptimoy Ghosh, Tarun Sharma
Note on gauge and gravitational anomalies of discrete $Z_N$ symmetries
Version to appear in JHEP
null
10.1007/JHEP01(2018)015
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this note, we discuss the consistency conditions which a discrete $Z_N$ symmetry should satisfy in order that it is not violated by gauge and gravitational instantons. As examples, we enlist all the $Z_N$ ${\cal R}$-symmetries as well as non-${\cal R}$ $Z_N$ symmetries (N=2,3,4) in the minimally supersymmetric standard model (MSSM) that are free from gauge and gravitational anomalies. We show that there exists non-anomalous discrete symmetries that forbid Baryon number violation up to dimension 6 level (in superspace). We also observe that there exists no non-anomalous $Z_3$ ${\cal R}$-symmetry in the MSSM. Furthermore, we point out that in a theory with one Majorana spin 3/2 gravitino, a large class of $Z_4$ ${\cal R}$-symmetries are violated in the presence of Eguchi-Hanson (EH) gravitational instanton. This is also in general true for higher $Z_N$ ${\cal R}$-symmetries. We also notice that in 4 dimensional ${\cal N}=1$ supergravity, the global $U(1)$ ${\cal R}$-symmetry is always violated by the EH instanton irrespective of the matter content of the theory.
[ { "created": "Wed, 12 Jul 2017 18:00:05 GMT", "version": "v1" }, { "created": "Sun, 27 Aug 2017 15:02:45 GMT", "version": "v2" }, { "created": "Tue, 26 Dec 2017 15:05:22 GMT", "version": "v3" } ]
2018-02-14
[ [ "Byakti", "Pritibhajan", "" ], [ "Ghosh", "Diptimoy", "" ], [ "Sharma", "Tarun", "" ] ]
In this note, we discuss the consistency conditions which a discrete $Z_N$ symmetry should satisfy in order that it is not violated by gauge and gravitational instantons. As examples, we enlist all the $Z_N$ ${\cal R}$-symmetries as well as non-${\cal R}$ $Z_N$ symmetries (N=2,3,4) in the minimally supersymmetric standard model (MSSM) that are free from gauge and gravitational anomalies. We show that there exists non-anomalous discrete symmetries that forbid Baryon number violation up to dimension 6 level (in superspace). We also observe that there exists no non-anomalous $Z_3$ ${\cal R}$-symmetry in the MSSM. Furthermore, we point out that in a theory with one Majorana spin 3/2 gravitino, a large class of $Z_4$ ${\cal R}$-symmetries are violated in the presence of Eguchi-Hanson (EH) gravitational instanton. This is also in general true for higher $Z_N$ ${\cal R}$-symmetries. We also notice that in 4 dimensional ${\cal N}=1$ supergravity, the global $U(1)$ ${\cal R}$-symmetry is always violated by the EH instanton irrespective of the matter content of the theory.
hep-ph/0512362
Michael Maziashvili
Michael Maziashvili
Particle escape into extra space
3 pages
Phys.Lett.B635:36-38,2006
10.1016/j.physletb.2006.02.032
null
hep-ph
null
We focus on escape of a spin integer particle the challenge for which is of course that the corresponding field equation contains the second order time derivative and, in general, may be problematic for interpreting the extra-dimensional part of the field as a wave function for the KK modes as it is usually regarded.
[ { "created": "Thu, 29 Dec 2005 13:23:08 GMT", "version": "v1" }, { "created": "Mon, 20 Feb 2006 09:16:29 GMT", "version": "v2" } ]
2010-11-05
[ [ "Maziashvili", "Michael", "" ] ]
We focus on escape of a spin integer particle the challenge for which is of course that the corresponding field equation contains the second order time derivative and, in general, may be problematic for interpreting the extra-dimensional part of the field as a wave function for the KK modes as it is usually regarded.
0911.2806
James Maxin
James A. Maxin, Van E. Mayes, and D.V. Nanopoulos
A Note on Modulus-dominated SUSY-breaking
14 pages, 2 figures
Phys.Lett.B690:501-507,2010
10.1016/j.physletb.2010.05.077
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In models where supersymmetry-breaking is dominated by the Kahler moduli and/or the universal dilaton, the B-parameter at the unification scale should be consistent with the value of tan(beta) at the electroweak scale determined by minimization of the Higgs potential triggering REWSB. We study such models employing a self-consistent determination of the B-parameter. In particular, we study the viability of a generic model, as well as M-theory and Type IIB flux compactifications with modulus-dominated supersymmetric soft-terms from the GUT scale, M_{GUT}=2x10^{16}GeV.
[ { "created": "Sat, 14 Nov 2009 20:51:38 GMT", "version": "v1" } ]
2010-09-16
[ [ "Maxin", "James A.", "" ], [ "Mayes", "Van E.", "" ], [ "Nanopoulos", "D. V.", "" ] ]
In models where supersymmetry-breaking is dominated by the Kahler moduli and/or the universal dilaton, the B-parameter at the unification scale should be consistent with the value of tan(beta) at the electroweak scale determined by minimization of the Higgs potential triggering REWSB. We study such models employing a self-consistent determination of the B-parameter. In particular, we study the viability of a generic model, as well as M-theory and Type IIB flux compactifications with modulus-dominated supersymmetric soft-terms from the GUT scale, M_{GUT}=2x10^{16}GeV.
0802.1286
Tadafumi Ohsaku
Tadafumi Ohsaku
Dynamical Mass Generations and Collective Excitations in the (Supersymmetric-)Nambu$-$Jona-Lasinio Model and a Gauge Theory with Left-Right-Asymmetric Majorana Mass Terms
98 pages, mathematical aspects enlarged
null
null
null
hep-ph hep-th math-ph math.MP math.RT
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The structure of effective potential surface of the Nambu$-$Jona-Lasinio (NJL) model with right-left asymmetric Majorana mass terms (corresponds to the single-flavor type-II seesaw situation of neutrino) is investigated. After the dynamical generation of Dirac mass, two collective modes appear similar to the case of ordinary NJL model, and the phase mode (phason), which corresponds to majoron or pion at vanishing Majorana mass parameter(s), has an excitation mass. The mechanism of generation of phason as a pseudo Nambu-Goldstone boson is examined by a mathematical manner, summarized into a theorem (claims as the generalized Nambu-Goldstone theorem). The mass of phason is also evaluated in a supersymmetric version of the NJL-type model, and phason mass takes the order of that of axion commonly accepted today. An $SU(2_{c})$-gauge model is constructed for the context of neutrino seesaw mechanism, and the Schwinger-Dyson equation of dynamical mass functions is examined. Several physical implications such as decay modes of phason, a non-linear sigma model for phason are given. It is proposed that the method/result of this paper can be applied to an understanding on the origin of the Kobayashi-Maskawa matrix.
[ { "created": "Sat, 9 Feb 2008 20:03:25 GMT", "version": "v1" }, { "created": "Fri, 10 Dec 2010 15:01:24 GMT", "version": "v10" }, { "created": "Fri, 4 Apr 2008 21:15:26 GMT", "version": "v2" }, { "created": "Thu, 9 Oct 2008 16:30:54 GMT", "version": "v3" }, { "cre...
2010-12-21
[ [ "Ohsaku", "Tadafumi", "" ] ]
The structure of effective potential surface of the Nambu$-$Jona-Lasinio (NJL) model with right-left asymmetric Majorana mass terms (corresponds to the single-flavor type-II seesaw situation of neutrino) is investigated. After the dynamical generation of Dirac mass, two collective modes appear similar to the case of ordinary NJL model, and the phase mode (phason), which corresponds to majoron or pion at vanishing Majorana mass parameter(s), has an excitation mass. The mechanism of generation of phason as a pseudo Nambu-Goldstone boson is examined by a mathematical manner, summarized into a theorem (claims as the generalized Nambu-Goldstone theorem). The mass of phason is also evaluated in a supersymmetric version of the NJL-type model, and phason mass takes the order of that of axion commonly accepted today. An $SU(2_{c})$-gauge model is constructed for the context of neutrino seesaw mechanism, and the Schwinger-Dyson equation of dynamical mass functions is examined. Several physical implications such as decay modes of phason, a non-linear sigma model for phason are given. It is proposed that the method/result of this paper can be applied to an understanding on the origin of the Kobayashi-Maskawa matrix.
hep-ph/0302198
Ansgar Denner
A. Denner, S. Dittmaier, M. Roth, M. M. Weber
Electroweak radiative corrections to e+ e- -> nu nubar H
35 pages, Latex, 17 postscript files
Nucl.Phys.B660:289-321,2003
10.1016/S0550-3213(03)00269-4
KA-TP-03-2003, MPI-PhT/2003-08, PSI-PR-03-05
hep-ph
null
The complete electroweak O(alpha) radiative corrections to the Higgs-boson production processes e+ e- -> nu_l anti-nu_l H (l=e,mu,tau) are calculated in the electroweak Standard Model. For e+ e- -> nu_e anti-nu_e H, where ZH production and W-boson fusion contribute, both production channels are added coherently. The calculation of the corrections is described in some detail including, in particular, the treatment of the Z-boson resonance in the ZH-production channel. The discussion of numerical results focusses on the total cross section as well as on angular and energy distributions of the Higgs boson. In the Gmu-scheme, the bulk of the corrections is due to initial-state radiation. The corrections turn out to reduce the total cross section by \sim 10% for high energies, where the W-boson fusion dominates. In this region, the corrections depend only weakly on the energy and the production angle of the Higgs boson. Based on an analysis of the leading universal corrections, a simple improved Born approximation is introduced. This approximation describes the corrected cross section within about 3%.
[ { "created": "Fri, 21 Feb 2003 16:50:01 GMT", "version": "v1" } ]
2008-11-26
[ [ "Denner", "A.", "" ], [ "Dittmaier", "S.", "" ], [ "Roth", "M.", "" ], [ "Weber", "M. M.", "" ] ]
The complete electroweak O(alpha) radiative corrections to the Higgs-boson production processes e+ e- -> nu_l anti-nu_l H (l=e,mu,tau) are calculated in the electroweak Standard Model. For e+ e- -> nu_e anti-nu_e H, where ZH production and W-boson fusion contribute, both production channels are added coherently. The calculation of the corrections is described in some detail including, in particular, the treatment of the Z-boson resonance in the ZH-production channel. The discussion of numerical results focusses on the total cross section as well as on angular and energy distributions of the Higgs boson. In the Gmu-scheme, the bulk of the corrections is due to initial-state radiation. The corrections turn out to reduce the total cross section by \sim 10% for high energies, where the W-boson fusion dominates. In this region, the corrections depend only weakly on the energy and the production angle of the Higgs boson. Based on an analysis of the leading universal corrections, a simple improved Born approximation is introduced. This approximation describes the corrected cross section within about 3%.
2407.06803
Mohammad Sajjad Athar
A. Fatima, M. Sajjad Athar, and S. K. Singh
Charged current weak production of $\Delta(1232)$ induced by electrons and positrons
21 pages, 9 figures, and 1 table
null
null
null
hep-ph hep-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
The charged current weak production of $\Delta (1232)$ from the free proton target induced by the electron/positron in the intermediate energy range corresponding to the beam energy available at JLab and Mainz, has been studied. The results for the differential scattering cross section $\frac{d\sigma}{dQ^2}$, the angular distribution $\frac{d\sigma}{d\Omega_{\Delta}}$, and the total scattering cross section $\sigma(E_e)$ for both the electron and positron induced processes are presented, for the various energies in the range of 0.5--4~GeV. The cross section $\sigma(E_e)$ is found to be of the order of $10^{-39}$~cm$^{2}$ for the electron/positron energies in the few GeV range. The availability of electron/positron beams having well defined energy and direction with very high luminosity of the order of $10^{38}-10^{39}$~cm$^{-2}$~sec$^{-1}$, makes it possible to observe the weak charged current production of $\Delta(1232)$ and determine the axial vector form factors $C_{i}^{A} (Q^2);~(i=3-5)$. The sensitivity of the differential cross section $\frac{d\sigma}{dQ^2}$ to the subdominant form factors $C_{3}^{A}(Q^2)$ and $C_{4}^{A} (Q^2)$ is found to be strong enough, especially in the low $Q^2$ region, which can be used to determine them phenomenologically and to test the various theoretical models proposed to calculate them.
[ { "created": "Tue, 9 Jul 2024 12:17:11 GMT", "version": "v1" } ]
2024-07-10
[ [ "Fatima", "A.", "" ], [ "Athar", "M. Sajjad", "" ], [ "Singh", "S. K.", "" ] ]
The charged current weak production of $\Delta (1232)$ from the free proton target induced by the electron/positron in the intermediate energy range corresponding to the beam energy available at JLab and Mainz, has been studied. The results for the differential scattering cross section $\frac{d\sigma}{dQ^2}$, the angular distribution $\frac{d\sigma}{d\Omega_{\Delta}}$, and the total scattering cross section $\sigma(E_e)$ for both the electron and positron induced processes are presented, for the various energies in the range of 0.5--4~GeV. The cross section $\sigma(E_e)$ is found to be of the order of $10^{-39}$~cm$^{2}$ for the electron/positron energies in the few GeV range. The availability of electron/positron beams having well defined energy and direction with very high luminosity of the order of $10^{38}-10^{39}$~cm$^{-2}$~sec$^{-1}$, makes it possible to observe the weak charged current production of $\Delta(1232)$ and determine the axial vector form factors $C_{i}^{A} (Q^2);~(i=3-5)$. The sensitivity of the differential cross section $\frac{d\sigma}{dQ^2}$ to the subdominant form factors $C_{3}^{A}(Q^2)$ and $C_{4}^{A} (Q^2)$ is found to be strong enough, especially in the low $Q^2$ region, which can be used to determine them phenomenologically and to test the various theoretical models proposed to calculate them.
hep-ph/9904324
Muneyuki Ishida
Rukmani Mohanta, Anjan K. Giri, Mohinder P. Khanna (Panjab University), Muneyuki Ishida(TIT), Shin Ishida (Nihon University) and Masuho Oda(Kokushikan University)
Hadronic Weak Decays of Lambda b Baryon in the Covariant Oscillator Quark Model
10 pages, uses ptptex.sty
Prog.Theor.Phys.101:959-969,1999
10.1143/PTP.101.959
NUP-A-99-5
hep-ph
null
Cabibbo allowed two-body hadronic weak decays of Lambda b baryons are analyzed in the factorization approximation. We use the covariant oscillator quark model to evaluate the heavy to heavy and heavy to light form factors. When applied in the heavy quark limit, our form factors satisfy all the constraints imposed by heavy quark symmetry. The decay rates and up-down asymmetries for Lambda b baryon decaying into Lambda c +P(V) are calculated. It is found that the up-down asymmetry is negative in all these decay modes. Furthermore, the prediction Br(Lambda b to Lambda+J/psi)=2.49 times 10^-4 is consistent with the recent experimental data. Finally it is pointed out that the CKM-Wolfenstein parameter rho^2+eta^2, where eta is the CP phase, can be determined from the ratio of the widths Lambda b to Lambda bar D^0 and Lambda b to Lambda J/psi, independent of the QCD parameter. The value of (rho^2 +eta^2)^1/2 calculated in our model agrees very well with the value recently predicted by Rosner.
[ { "created": "Wed, 14 Apr 1999 03:43:46 GMT", "version": "v1" } ]
2011-03-23
[ [ "Mohanta", "Rukmani", "", "Panjab\n University" ], [ "Giri", "Anjan K.", "", "Panjab\n University" ], [ "Khanna", "Mohinder P.", "", "Panjab\n University" ], [ "Ishida", "Muneyuki", "", "TIT" ], [ "Ishida", "Shin", "", ...
Cabibbo allowed two-body hadronic weak decays of Lambda b baryons are analyzed in the factorization approximation. We use the covariant oscillator quark model to evaluate the heavy to heavy and heavy to light form factors. When applied in the heavy quark limit, our form factors satisfy all the constraints imposed by heavy quark symmetry. The decay rates and up-down asymmetries for Lambda b baryon decaying into Lambda c +P(V) are calculated. It is found that the up-down asymmetry is negative in all these decay modes. Furthermore, the prediction Br(Lambda b to Lambda+J/psi)=2.49 times 10^-4 is consistent with the recent experimental data. Finally it is pointed out that the CKM-Wolfenstein parameter rho^2+eta^2, where eta is the CP phase, can be determined from the ratio of the widths Lambda b to Lambda bar D^0 and Lambda b to Lambda J/psi, independent of the QCD parameter. The value of (rho^2 +eta^2)^1/2 calculated in our model agrees very well with the value recently predicted by Rosner.
1901.01635
Igor Altsybeev
Igor Altsybeev
Recent developments in particle yield fluctuation measurements
Proceedings of XXIV Baldin ISHEPP (Dubna, Russia, 2018)
EPJ Web of Conferences 204, 2019
10.1051/epjconf/201920403003
null
hep-ph nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In relativistic heavy-ion collisions, properties of the initial state and effects arising during evolution of the medium, such as a transition between the hadronic and partonic phases, should reflect themselves in event-by-event fluctuations of the number of produced particles. In this paper, recent measurements of several event-by-event observables, namely, dynamical fluctuations of relative particle yields and forward-backward correlations of different types, are discussed. Also, new observables for forward-backward correlation studies are proposed: correlations between ratios of identified particle yields in two separated acceptance intervals and the correlation between the ratio in one interval and average transverse momentum in another.
[ { "created": "Mon, 7 Jan 2019 01:11:26 GMT", "version": "v1" } ]
2019-04-05
[ [ "Altsybeev", "Igor", "" ] ]
In relativistic heavy-ion collisions, properties of the initial state and effects arising during evolution of the medium, such as a transition between the hadronic and partonic phases, should reflect themselves in event-by-event fluctuations of the number of produced particles. In this paper, recent measurements of several event-by-event observables, namely, dynamical fluctuations of relative particle yields and forward-backward correlations of different types, are discussed. Also, new observables for forward-backward correlation studies are proposed: correlations between ratios of identified particle yields in two separated acceptance intervals and the correlation between the ratio in one interval and average transverse momentum in another.
hep-ph/0612366
Michael Kuchiev
Victor Flambaum and Michael Kuchiev
Charge density of a positively charged vector boson may be negative
4 pages, revtex
Phys.Rev.Lett.98:181805,2007
10.1103/PhysRevLett.98.181805
null
hep-ph
null
The charge density of vector particles, for example W, may change sign. The effect manifests itself even for a free propagation; when the energy of the W-boson is higher than sqrt{2}m and the standing-wave is considered the charge density oscillates in space. The charge density of W also changes sign in close vicinity of a Coulomb center. The dependence of this effect on the g-factor for an arbitrary vector boson, for example rho-meson, is discussed. An origin of this surprising effect is traced to the electric quadrupole moment and spin-orbit interaction of vector particles. Their contributions to the current have a polarization nature. The charge density of this current, rho = -\nabla \cdot P, where P is an effective polarization vector that depends on the quadrupole moment and spin-orbit interaction, oscillates in space, producing zero contribution to the total charge.
[ { "created": "Fri, 29 Dec 2006 04:05:22 GMT", "version": "v1" } ]
2008-11-26
[ [ "Flambaum", "Victor", "" ], [ "Kuchiev", "Michael", "" ] ]
The charge density of vector particles, for example W, may change sign. The effect manifests itself even for a free propagation; when the energy of the W-boson is higher than sqrt{2}m and the standing-wave is considered the charge density oscillates in space. The charge density of W also changes sign in close vicinity of a Coulomb center. The dependence of this effect on the g-factor for an arbitrary vector boson, for example rho-meson, is discussed. An origin of this surprising effect is traced to the electric quadrupole moment and spin-orbit interaction of vector particles. Their contributions to the current have a polarization nature. The charge density of this current, rho = -\nabla \cdot P, where P is an effective polarization vector that depends on the quadrupole moment and spin-orbit interaction, oscillates in space, producing zero contribution to the total charge.
2112.02477
Bin Yan
Yandong Liu and Bin Yan
Searching for the axion-like particle at the EIC
5 pages, 5 figures, published version
null
10.1088/1674-1137/acbbc0
LA-UR-21-31766
hep-ph hep-ex nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The axion-like particle (ALP) is a well motivated new particle candidate of beyond the Standard Model. In this work, we propose to probe the ALP through the photon fusion scattering at the upcoming Electron-Ion Collider (EIC) with electron and proton energy $E_e=20~{\rm GeV}$ and $E_p=250~{\rm GeV}$. It shows that we could constrain the effective coupling strength between ALP and photons to be $0.2~{\rm TeV}^{-1}$ at $2\sigma$ confidence level with the integrated luminosity of $300~{\rm fb}^{-1}$ for the mass range $m_a\in [5,40]~{\rm GeV}$. Such bound could be much improved if we consider the nucleus beam at the EIC. We also demonstrate that the limits from the EIC could be stronger than the off $Z$-pole measurement at the LEP and the Light-by-Light scattering with pp collision at the LHC.
[ { "created": "Sun, 5 Dec 2021 04:52:05 GMT", "version": "v1" }, { "created": "Thu, 16 Feb 2023 01:41:04 GMT", "version": "v2" } ]
2023-03-29
[ [ "Liu", "Yandong", "" ], [ "Yan", "Bin", "" ] ]
The axion-like particle (ALP) is a well motivated new particle candidate of beyond the Standard Model. In this work, we propose to probe the ALP through the photon fusion scattering at the upcoming Electron-Ion Collider (EIC) with electron and proton energy $E_e=20~{\rm GeV}$ and $E_p=250~{\rm GeV}$. It shows that we could constrain the effective coupling strength between ALP and photons to be $0.2~{\rm TeV}^{-1}$ at $2\sigma$ confidence level with the integrated luminosity of $300~{\rm fb}^{-1}$ for the mass range $m_a\in [5,40]~{\rm GeV}$. Such bound could be much improved if we consider the nucleus beam at the EIC. We also demonstrate that the limits from the EIC could be stronger than the off $Z$-pole measurement at the LEP and the Light-by-Light scattering with pp collision at the LHC.
2308.07566
Supriya Pan
Supriya Pan (1 and 2), Kaustav Chakraborty (1), Srubabati Goswami (1) ((1) Physical Research Laboratory, Ahmedabad, (2) Indian Institute of Technology, Gandhinagar)
Sensitivity to CP Discovery in the Presence of Lorentz Invariance Violating Potential at T2HK/T2HKK
10 pages, 11 figures
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Investigation of conservation/violation of CP symmetry in the leptonic sector is very essential in understanding the evolution of the universe. Lorentz invariance and CPT are fundamental symmetries of nature. The violation of Lorentz invariance can also lead to CPT violations. The standard three flavour neutrino oscillation framework presents a scenario to observe the signature of Lorentz invariance and CP violations. This work focuses on the effect of Lorentz invariance violating (LIV) parameters on the sensitivity to CP violation. We investigate the sensitivity in two proposed configurations of the upcoming T2HK experiment: (i) one detector each placed at 295 km and 1100 km, and (ii) two identical detectors at 295 km. This study probes the effect of CPT violating parameters $a_{e\mu},a_{e\tau},a_{\mu\tau}$.
[ { "created": "Tue, 15 Aug 2023 04:23:31 GMT", "version": "v1" }, { "created": "Fri, 22 Sep 2023 09:35:29 GMT", "version": "v2" } ]
2023-09-25
[ [ "Pan", "Supriya", "", "1 and 2" ], [ "Chakraborty", "Kaustav", "" ], [ "Goswami", "Srubabati", "" ] ]
Investigation of conservation/violation of CP symmetry in the leptonic sector is very essential in understanding the evolution of the universe. Lorentz invariance and CPT are fundamental symmetries of nature. The violation of Lorentz invariance can also lead to CPT violations. The standard three flavour neutrino oscillation framework presents a scenario to observe the signature of Lorentz invariance and CP violations. This work focuses on the effect of Lorentz invariance violating (LIV) parameters on the sensitivity to CP violation. We investigate the sensitivity in two proposed configurations of the upcoming T2HK experiment: (i) one detector each placed at 295 km and 1100 km, and (ii) two identical detectors at 295 km. This study probes the effect of CPT violating parameters $a_{e\mu},a_{e\tau},a_{\mu\tau}$.
0907.4374
Lorenzo Ubaldi
Stefano Profumo (UCSC), Kris Sigurdson (UBC) and Lorenzo Ubaldi (UCSC)
Can we discover dual-component thermal WIMP dark matter?
44 pages, 16 figures, revised version published in JCAP
JCAP 0912:016,2009
10.1088/1475-7516/2009/12/016
null
hep-ph astro-ph.HE hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address the question of whether the upcoming generation of dark matter search experiments and colliders will be able to discover if the dark matter in the Universe has two components of weakly interacting massive particles (WIMPs). We outline a model-independent approach, and we study the specific cases of (1) direct detection with low-background 1 ton noble-gas detectors and (2) a 0.5 TeV center of mass energy electron-positron linear collider. We also analyze the case of indirect detection via two gamma-ray lines, which would provide a verification of such a discovery, although multiple gamma-ray lines can in principle originate from the annihilation of a single dark matter particle. For each search "channel", we outline a few assumptions to relate the very small set of parameters we consider (defining the masses of the two WIMPs and their relative abundance in the overall dark matter density) with the relevant detection rates. We then draw general conclusions on which corners of a generic dual-component dark matter scenario can be explored with current and next generation experiments. We find that in all channels the ideal setup is one where the relative mass splitting between the two WIMP species is of order 1, and where the two dark matter components contribute in a ratio close to 1:1 to the overall dark matter content of the Universe. Interestingly, in the case of direct detection, future experiments might detect multiple states even if only ~ 10% of the energy-density of dark matter in the Universe is in the subdominant species.
[ { "created": "Sat, 25 Jul 2009 06:36:37 GMT", "version": "v1" }, { "created": "Thu, 8 Oct 2009 18:49:02 GMT", "version": "v2" }, { "created": "Wed, 23 Dec 2009 13:48:17 GMT", "version": "v3" } ]
2009-12-23
[ [ "Profumo", "Stefano", "", "UCSC" ], [ "Sigurdson", "Kris", "", "UBC" ], [ "Ubaldi", "Lorenzo", "", "UCSC" ] ]
We address the question of whether the upcoming generation of dark matter search experiments and colliders will be able to discover if the dark matter in the Universe has two components of weakly interacting massive particles (WIMPs). We outline a model-independent approach, and we study the specific cases of (1) direct detection with low-background 1 ton noble-gas detectors and (2) a 0.5 TeV center of mass energy electron-positron linear collider. We also analyze the case of indirect detection via two gamma-ray lines, which would provide a verification of such a discovery, although multiple gamma-ray lines can in principle originate from the annihilation of a single dark matter particle. For each search "channel", we outline a few assumptions to relate the very small set of parameters we consider (defining the masses of the two WIMPs and their relative abundance in the overall dark matter density) with the relevant detection rates. We then draw general conclusions on which corners of a generic dual-component dark matter scenario can be explored with current and next generation experiments. We find that in all channels the ideal setup is one where the relative mass splitting between the two WIMP species is of order 1, and where the two dark matter components contribute in a ratio close to 1:1 to the overall dark matter content of the Universe. Interestingly, in the case of direct detection, future experiments might detect multiple states even if only ~ 10% of the energy-density of dark matter in the Universe is in the subdominant species.
1502.05703
Sascha Caron
Abraham Achterberg, Simone Amoroso, Sascha Caron, Luc Hendriks, Roberto Ruiz de Austri, Christoph Weniger
A description of the Galactic Center excess in the Minimal Supersymmetric Standard Model
Large extension of previous paper: 2 more solutions found in the MSSM (Bino-Higgsino, Bino-Wino-Higgsino into WW and Bino into ttbar), added description on extra fit uncertainties, added description on flavor observables, added discussion on dwarf limits
null
10.1088/1475-7516/2015/08/006
null
hep-ph astro-ph.CO astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Observations with the Fermi Large Area Telescope (LAT) indicate an excess in gamma rays originating from the center of our Galaxy. A possible explanation for this excess is the annihilation of Dark Matter particles. We have investigated the annihilation of neutralinos as Dark Matter candidates within the phenomenological Minimal Supersymmetric Standard Model (pMSSM). An iterative particle filter approach was used to search for solutions within the pMSSM. We found solutions that are consistent with astroparticle physics and collider experiments, and provide a fit to the energy spectrum of the excess. The neutralino is a Bino/Higgsino or Bino/Wino/Higgsino mixture with a mass in the range $84-92$~GeV or $87-97$~GeV annihilating into W bosons. A third solutions is found for a neutralino of mass $174-187$~GeV annihilating into top quarks. The best solutions yield a Dark Matter relic density $0.06 < \Omega h^2 <0.13$. These pMSSM solutions make clear forecasts for LHC, direct and indirect DM detection experiments. If the MSSM explanation of the excess seen by Fermi-LAT is correct, a DM signal might be discovered soon.
[ { "created": "Thu, 19 Feb 2015 20:55:49 GMT", "version": "v1" }, { "created": "Tue, 31 Mar 2015 16:10:18 GMT", "version": "v2" } ]
2015-08-19
[ [ "Achterberg", "Abraham", "" ], [ "Amoroso", "Simone", "" ], [ "Caron", "Sascha", "" ], [ "Hendriks", "Luc", "" ], [ "de Austri", "Roberto Ruiz", "" ], [ "Weniger", "Christoph", "" ] ]
Observations with the Fermi Large Area Telescope (LAT) indicate an excess in gamma rays originating from the center of our Galaxy. A possible explanation for this excess is the annihilation of Dark Matter particles. We have investigated the annihilation of neutralinos as Dark Matter candidates within the phenomenological Minimal Supersymmetric Standard Model (pMSSM). An iterative particle filter approach was used to search for solutions within the pMSSM. We found solutions that are consistent with astroparticle physics and collider experiments, and provide a fit to the energy spectrum of the excess. The neutralino is a Bino/Higgsino or Bino/Wino/Higgsino mixture with a mass in the range $84-92$~GeV or $87-97$~GeV annihilating into W bosons. A third solutions is found for a neutralino of mass $174-187$~GeV annihilating into top quarks. The best solutions yield a Dark Matter relic density $0.06 < \Omega h^2 <0.13$. These pMSSM solutions make clear forecasts for LHC, direct and indirect DM detection experiments. If the MSSM explanation of the excess seen by Fermi-LAT is correct, a DM signal might be discovered soon.
1902.04582
Alexander Ridgway K
Alexander K. Ridgway and Mark B. Wise
An Estimate of the Inclusive Branching Ratio to ${\bar B}_c$ in $\Xi_{bbq}$ Decay
6 pages, 2 figures
null
10.1016/j.physletb.2019.04.020
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We estimate the branching ratio for the inclusive decays $\Xi_{bbq} \rightarrow {\bar B}_c^{(*)}+X_{c,s,q}$ to be approximately 1%. Our estimate is performed using non-relativistic potential quark model methods that are appropriate if the bottom and charm quarks are heavy compared to the strong interaction scale. Here the superscript $(*)$ denotes that we are summing over spin zero ${\bar B}_c$ and spin one ${\bar B}_c^*$ mesons and the subscript $q$ denotes a light quark. Our approach treats the two bottom quarks in the baryon $\Xi_{bbq}$ as a small color anti-triplet. This estimate for the inclusive branching ratio to ${\bar B}_c$ and ${\bar B}^*_c$ mesons also holds for decays of the lowest lying $T_{bb{\bar q}{\bar q}}$ tetraquark states, provided they are stable against strong and electromagnetic decay.
[ { "created": "Tue, 12 Feb 2019 19:00:00 GMT", "version": "v1" } ]
2019-04-17
[ [ "Ridgway", "Alexander K.", "" ], [ "Wise", "Mark B.", "" ] ]
We estimate the branching ratio for the inclusive decays $\Xi_{bbq} \rightarrow {\bar B}_c^{(*)}+X_{c,s,q}$ to be approximately 1%. Our estimate is performed using non-relativistic potential quark model methods that are appropriate if the bottom and charm quarks are heavy compared to the strong interaction scale. Here the superscript $(*)$ denotes that we are summing over spin zero ${\bar B}_c$ and spin one ${\bar B}_c^*$ mesons and the subscript $q$ denotes a light quark. Our approach treats the two bottom quarks in the baryon $\Xi_{bbq}$ as a small color anti-triplet. This estimate for the inclusive branching ratio to ${\bar B}_c$ and ${\bar B}^*_c$ mesons also holds for decays of the lowest lying $T_{bb{\bar q}{\bar q}}$ tetraquark states, provided they are stable against strong and electromagnetic decay.
1810.01079
C. Q. Geng
C.Q. Geng, Y.K. Hsiao, Chia-Wei Liu and Tien-Hsueh Tsai
Three-body charmed baryon Decays with SU(3) flavor symmetry
14 pages, no figure, revised version accepted by PRD
Phys. Rev. D 99, 073003 (2019)
10.1103/PhysRevD.99.073003
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the three-body anti-triplet ${\bf B_c}\to {\bf B_n}MM'$ decays with the $SU(3)$ flavor ($SU(3)_f$) symmetry, where ${\bf B_c}$ denotes the charmed baryon anti-triplet of $(\Xi_c^0,-\Xi_c^+,\Lambda_c^+)$, and ${\bf B_n}$ and $M(M')$ represent baryon and meson octets, respectively. By considering only the S-wave $MM'$-pair contributions without resonance effects, the decays of ${\bf B_c}\to {\bf B_n}MM'$ can be decomposed into irreducible forms with 11 parameters under $SU(3)_f$, which are fitted by the 14 existing data, resulting in a reasonable value of $\chi^2/d.o.f=2.8$ for the fit. Consequently, we find that the triangle sum rule of ${\cal A}(\Lambda_c^+\to n\bar K^0 \pi^+)-{\cal A}(\Lambda_c^+\to pK^- \pi^+)-\sqrt 2 {\cal A}(\Lambda_c^+\to p\bar K^0 \pi^0)=0$ given by the isospin symmetry holds under $SU(3)_f$, where ${\cal A}$ stands for the decay amplitude. In addition, we predict that ${\cal B}(\Lambda_c^+\to n \pi^{+} \bar{K}^{0})=(0.9\pm 0.8)\times 10^{-2}$, which is $3-4$ times smaller than the BESIII observation, indicating the existence of the resonant states. For the to-be-observed ${\bf B_c}\to {\bf B_n}MM'$ decays, we compute the branching fractions with the $SU(3)_f$ amplitudes to be compared to the BESIII and LHCb measurements in the future.
[ { "created": "Tue, 2 Oct 2018 05:44:50 GMT", "version": "v1" }, { "created": "Wed, 27 Mar 2019 07:09:14 GMT", "version": "v2" } ]
2019-04-17
[ [ "Geng", "C. Q.", "" ], [ "Hsiao", "Y. K.", "" ], [ "Liu", "Chia-Wei", "" ], [ "Tsai", "Tien-Hsueh", "" ] ]
We study the three-body anti-triplet ${\bf B_c}\to {\bf B_n}MM'$ decays with the $SU(3)$ flavor ($SU(3)_f$) symmetry, where ${\bf B_c}$ denotes the charmed baryon anti-triplet of $(\Xi_c^0,-\Xi_c^+,\Lambda_c^+)$, and ${\bf B_n}$ and $M(M')$ represent baryon and meson octets, respectively. By considering only the S-wave $MM'$-pair contributions without resonance effects, the decays of ${\bf B_c}\to {\bf B_n}MM'$ can be decomposed into irreducible forms with 11 parameters under $SU(3)_f$, which are fitted by the 14 existing data, resulting in a reasonable value of $\chi^2/d.o.f=2.8$ for the fit. Consequently, we find that the triangle sum rule of ${\cal A}(\Lambda_c^+\to n\bar K^0 \pi^+)-{\cal A}(\Lambda_c^+\to pK^- \pi^+)-\sqrt 2 {\cal A}(\Lambda_c^+\to p\bar K^0 \pi^0)=0$ given by the isospin symmetry holds under $SU(3)_f$, where ${\cal A}$ stands for the decay amplitude. In addition, we predict that ${\cal B}(\Lambda_c^+\to n \pi^{+} \bar{K}^{0})=(0.9\pm 0.8)\times 10^{-2}$, which is $3-4$ times smaller than the BESIII observation, indicating the existence of the resonant states. For the to-be-observed ${\bf B_c}\to {\bf B_n}MM'$ decays, we compute the branching fractions with the $SU(3)_f$ amplitudes to be compared to the BESIII and LHCb measurements in the future.
1607.00838
Bruno Machet
Bruno Machet
1-loop mass generation by a constant external magnetic field for an electron propagating in a thin medium
26 pages, 10 figures. Version to appear in Int. J. Mod. Phys. B (2018)
null
10.1142/S021797921850114X
null
hep-ph cond-mat.mes-hall
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The 1-loop self-energy of a Dirac electron of mass m propagating in a thin medium simulating graphene in an external magnetic field B is investigated in Quantum Field Theory. Equivalence is shown with the so-called reduced QED_{3+1} on a 2-brane. Schwinger-like methods are used to calculate the self-mass \delta m_{LLL} of the electron when it lies in the lowest Landau level. Unlike in standard QED_{3+1}, it does not vanish at the limit m -> 0 :\delta m_{LLL} -> (\alpha/2)\sqrt{pi/2}sqrt{\hbar|e|B/c^2}; all Landau levels of the virtual electron are taken into account and on mass-shell renormalization conditions are implemented. Restricting to the sole lowest Landau level of the virtual electron is explicitly shown to be inadequate. Resummations at higher orders lie beyond the scope of this work.
[ { "created": "Mon, 4 Jul 2016 12:04:37 GMT", "version": "v1" }, { "created": "Tue, 13 Mar 2018 13:38:03 GMT", "version": "v2" } ]
2018-03-14
[ [ "Machet", "Bruno", "" ] ]
The 1-loop self-energy of a Dirac electron of mass m propagating in a thin medium simulating graphene in an external magnetic field B is investigated in Quantum Field Theory. Equivalence is shown with the so-called reduced QED_{3+1} on a 2-brane. Schwinger-like methods are used to calculate the self-mass \delta m_{LLL} of the electron when it lies in the lowest Landau level. Unlike in standard QED_{3+1}, it does not vanish at the limit m -> 0 :\delta m_{LLL} -> (\alpha/2)\sqrt{pi/2}sqrt{\hbar|e|B/c^2}; all Landau levels of the virtual electron are taken into account and on mass-shell renormalization conditions are implemented. Restricting to the sole lowest Landau level of the virtual electron is explicitly shown to be inadequate. Resummations at higher orders lie beyond the scope of this work.
hep-ph/9708327
Adam Falk
Adam F. Falk and Michael Luke
Hadronic Spectral Moments in Semileptonic B Decays With a Lepton Energy Cut
13 pages, 5 figures, REVTeX
Phys.Rev.D57:424-430,1998
10.1103/PhysRevD.57.424
JHU-TIPAC-97010, UTPT-97-09
hep-ph
null
We compute the first two moments of the final hadronic invariant mass in inclusive semileptonic B decay, in the presence of a cut on the charged lepton energy. These moments may be measured directly by experiments at the Upsilon(4S) using the neutrino reconstruction technique, which requires such a cut. Measurement of these moments will place constraints on the nonperturbative parameters \bar\Lambda and \lambda_1, which are relevant for extracting the quark masses m_b and m_c, as well as the CKM angle V_cb. We include terms of order \alpha_s^2\beta_0 and 1/m_b^3 in the operator product expansion, and use the latter to estimate the theoretical uncertainty in the extraction of \bar\Lambda and \lambda_1.
[ { "created": "Tue, 12 Aug 1997 18:01:07 GMT", "version": "v1" } ]
2014-11-17
[ [ "Falk", "Adam F.", "" ], [ "Luke", "Michael", "" ] ]
We compute the first two moments of the final hadronic invariant mass in inclusive semileptonic B decay, in the presence of a cut on the charged lepton energy. These moments may be measured directly by experiments at the Upsilon(4S) using the neutrino reconstruction technique, which requires such a cut. Measurement of these moments will place constraints on the nonperturbative parameters \bar\Lambda and \lambda_1, which are relevant for extracting the quark masses m_b and m_c, as well as the CKM angle V_cb. We include terms of order \alpha_s^2\beta_0 and 1/m_b^3 in the operator product expansion, and use the latter to estimate the theoretical uncertainty in the extraction of \bar\Lambda and \lambda_1.
hep-ph/9312352
null
R. D. Peccei, Ucla
Standard Model Expectations for CP Violation
55 pages, UCLA/93/TEP/50. Figures available upon request to reyes@physics.ucla.edu
null
null
null
hep-ph
null
I review the predictions and expectations of the CKM model for CP violation in both the $K^0-\bar K^0$ and $B^0-\bar B^0$ systems. A brief discussion of CP violation in charged $K$- and $B$-decays is also included, as well as some remarks on the electric dipole moments of the neutron and the electron.
[ { "created": "Thu, 30 Dec 1993 01:21:00 GMT", "version": "v1" } ]
2007-05-23
[ [ "Peccei", "R. D.", "" ], [ "Ucla", "", "" ] ]
I review the predictions and expectations of the CKM model for CP violation in both the $K^0-\bar K^0$ and $B^0-\bar B^0$ systems. A brief discussion of CP violation in charged $K$- and $B$-decays is also included, as well as some remarks on the electric dipole moments of the neutron and the electron.
hep-ph/0305213
Kunihiko Terasaki
K. Terasaki
BABAR resonance as a new window of hadron physics
3 pages, 0 figure
Phys.Rev.D68:011501,2003
10.1103/PhysRevD.68.011501
YITP-03-28
hep-ph
null
Possible decays of four-quark mesons are studied by assigning the newly observed BABAR resonance to a four-quark meson with C=S=I=1. It is expected that some of them can be observed as narrow resonances. Implication of existence of four-quark mesons in hadronic weak interactions is also discussed.
[ { "created": "Tue, 20 May 2003 07:42:08 GMT", "version": "v1" }, { "created": "Wed, 21 May 2003 05:20:11 GMT", "version": "v2" } ]
2008-11-26
[ [ "Terasaki", "K.", "" ] ]
Possible decays of four-quark mesons are studied by assigning the newly observed BABAR resonance to a four-quark meson with C=S=I=1. It is expected that some of them can be observed as narrow resonances. Implication of existence of four-quark mesons in hadronic weak interactions is also discussed.
1112.2675
David Eby
David A. Eby and Paul H. Frampton
Nonzero theta_13 signals nonmaximal atmospheric neutrino mixing
4 pages, 1 figure. Published version Phys. Rev. D
Phys. Rev. D86 (2012) 117304
10.1103/PhysRevD.86.117304
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
From recent groundbreaking experiments, it is now known that the Pontecorvo-Maki-Nakagawa-Sakata mixing differs significantly from the tribimaximal model in which theta_13=0 and theta_23=pi/4. Flavor symmetry can require that the departures from these two equations are linearly related. T' and A_4, which successfully accommodated the pre-T2K Pontecorvo-Maki-Nakagawa-Sakata matrix, predict that 38.07 deg.< theta_23 <39.52 deg. at 95% C.L.. The best fit values, combining the model predictions with T2K, MINOS, Double Chooz, Daya Bay, and RENO data, are theta_23=38.7 deg. and theta_13=8.9 deg..
[ { "created": "Mon, 12 Dec 2011 20:08:59 GMT", "version": "v1" }, { "created": "Thu, 15 Mar 2012 18:59:13 GMT", "version": "v2" }, { "created": "Tue, 20 Nov 2012 18:19:45 GMT", "version": "v3" }, { "created": "Fri, 23 Nov 2012 17:34:09 GMT", "version": "v4" }, { "c...
2013-01-17
[ [ "Eby", "David A.", "" ], [ "Frampton", "Paul H.", "" ] ]
From recent groundbreaking experiments, it is now known that the Pontecorvo-Maki-Nakagawa-Sakata mixing differs significantly from the tribimaximal model in which theta_13=0 and theta_23=pi/4. Flavor symmetry can require that the departures from these two equations are linearly related. T' and A_4, which successfully accommodated the pre-T2K Pontecorvo-Maki-Nakagawa-Sakata matrix, predict that 38.07 deg.< theta_23 <39.52 deg. at 95% C.L.. The best fit values, combining the model predictions with T2K, MINOS, Double Chooz, Daya Bay, and RENO data, are theta_23=38.7 deg. and theta_13=8.9 deg..
hep-ph/9509367
Dr. M. Pluemer
U. Ornik, M. Plumer, A. Timmermann, R.W. Weiner
Pre-Equilibrium Stage and Phase Transition of Quark Matter Probed by Photon Interferometry
10 pages, 3 Figures in uuencoded Postscript
null
null
null
hep-ph
null
We study single- and double-inclusive spectra of thermal photons, produced in heavy-ion collisions at $\sqrt{s}=200$ AGeV within a realistic space-time framework which combines the Parton-Cascade-Model and 3-dimensional hydrodynamics (HYLANDER). This allows also for the first time to take into account pre-equilibrium effects for photon production. A rapid decrease in the width of the correlation function as the photon transverse momentum drops below $\sim 1.5$ GeV is a signature of the deconfinement phase transition.
[ { "created": "Fri, 22 Sep 1995 14:00:44 GMT", "version": "v1" }, { "created": "Tue, 26 Sep 1995 11:39:42 GMT", "version": "v2" } ]
2008-02-03
[ [ "Ornik", "U.", "" ], [ "Plumer", "M.", "" ], [ "Timmermann", "A.", "" ], [ "Weiner", "R. W.", "" ] ]
We study single- and double-inclusive spectra of thermal photons, produced in heavy-ion collisions at $\sqrt{s}=200$ AGeV within a realistic space-time framework which combines the Parton-Cascade-Model and 3-dimensional hydrodynamics (HYLANDER). This allows also for the first time to take into account pre-equilibrium effects for photon production. A rapid decrease in the width of the correlation function as the photon transverse momentum drops below $\sim 1.5$ GeV is a signature of the deconfinement phase transition.
1408.4734
Marcus Bluhm
Marcus Bluhm (NCSU, Raleigh), Paolo Alba, Wanda Alberico (INFN, Turin & Turin U.), Rene Bellwied (Houston U.), Valentina Mantovani Sarti (INFN, Turin & Turin U.), Marlene Nahrgang (Duke U.), Claudia Ratti (INFN, Turin & Turin U.)
Determination of freeze-out conditions from fluctuation observables measured at RHIC
Proceedings of the 24th Quark Matter conference, 19-24 May 2014, Darmstadt, Germany. 4 pp
null
10.1016/j.nuclphysa.2014.08.016
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extract chemical freeze-out conditions via a thermal model approach from fluctuation observables measured at RHIC and compare with results from lattice QCD and statistical hadronization model fits. The possible influence of additional critical and non-critical fluctuation sources not accounted for in our analysis is discussed.
[ { "created": "Wed, 20 Aug 2014 17:22:15 GMT", "version": "v1" } ]
2014-08-21
[ [ "Bluhm", "Marcus", "", "NCSU, Raleigh" ], [ "Alba", "Paolo", "", "INFN, Turin\n & Turin U." ], [ "Alberico", "Wanda", "", "INFN, Turin\n & Turin U." ], [ "Bellwied", "Rene", "", "Houston U." ], [ "Sarti", "Valentina Mantovan...
We extract chemical freeze-out conditions via a thermal model approach from fluctuation observables measured at RHIC and compare with results from lattice QCD and statistical hadronization model fits. The possible influence of additional critical and non-critical fluctuation sources not accounted for in our analysis is discussed.
1406.6978
Valentina De Romeri
A. Abada, V. De Romeri and A.M. Teixeira
Effect of steriles states on lepton magnetic moments and neutrinoless double beta decay
25 pages, 19 figures
null
10.1007/JHEP09(2014)074
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address the impact of sterile fermion states on the anomalous magnetic moment of charged leptons, as well as their contribution to neutrinoless double beta decays. We illustrate our results in a minimal, effective extension of the Standard Model by one sterile fermion state, and in a well-motivated framework of neutrino mass generation, embedding the Inverse Seesaw into the Standard Model. The simple "3+1" effective case succeeds in alleviating the tension related to the muon anomalous magnetic moment, albeit only at the 3$\sigma$ level, and for light sterile states (corresponding to a }cosmologically disfavoured regime). Interestingly, our analysis shows that a future $0 \nu 2 \beta$ observation does not necessarily imply an inverted hierarchy for the active neutrinos in this simple extension. Although the Inverse Seesaw realisation here addressed could indeed ease the tension in $(g-2)_\mu$, bounds from lepton universality in kaon decays mostly preclude this from happening. However, these scenarios can also have a strong impact on the interpretation of a future $0 \nu 2 \beta$ signal regarding the hierarchy of the active neutrino mass spectrum.
[ { "created": "Thu, 26 Jun 2014 18:50:07 GMT", "version": "v1" } ]
2015-06-22
[ [ "Abada", "A.", "" ], [ "De Romeri", "V.", "" ], [ "Teixeira", "A. M.", "" ] ]
We address the impact of sterile fermion states on the anomalous magnetic moment of charged leptons, as well as their contribution to neutrinoless double beta decays. We illustrate our results in a minimal, effective extension of the Standard Model by one sterile fermion state, and in a well-motivated framework of neutrino mass generation, embedding the Inverse Seesaw into the Standard Model. The simple "3+1" effective case succeeds in alleviating the tension related to the muon anomalous magnetic moment, albeit only at the 3$\sigma$ level, and for light sterile states (corresponding to a }cosmologically disfavoured regime). Interestingly, our analysis shows that a future $0 \nu 2 \beta$ observation does not necessarily imply an inverted hierarchy for the active neutrinos in this simple extension. Although the Inverse Seesaw realisation here addressed could indeed ease the tension in $(g-2)_\mu$, bounds from lepton universality in kaon decays mostly preclude this from happening. However, these scenarios can also have a strong impact on the interpretation of a future $0 \nu 2 \beta$ signal regarding the hierarchy of the active neutrino mass spectrum.
2007.06851
Urs Wiedemann A
Aleksi Kurkela, Seyed Farid Taghavi, Urs Achim Wiedemann and Bin Wu
Hydrodynamization in systems with detailed transverse profiles
null
null
10.1016/j.physletb.2020.135901
CERN-TH-2020-118
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The observation of fluid-like behavior in nucleus-nucleus, proton-nucleus and high-multiplicity proton-proton collisions motivates systematic studies of how different measurements approach their fluid-dynamic limit. We have developed numerical methods to solve the ultra-relativistic Boltzmann equation for systems of arbitrary size and transverse geometry. Here, we apply these techniques for the first time to the study of azimuthal flow coefficients $v_n$ including non-linear mode-mode coupling and to an initial condition with realistic event-by-event fluctuations. We show how both linear and non-linear response coefficients extracted from $v_n$ develop as a function of opacity from free streaming to perfect fluidity. We note in particular that away from the fluid-dynamic limit, the signal strength of linear and non-linear response coefficients does not reduce uniformly, but that their hierarchy and relative size shows characteristic differences.
[ { "created": "Tue, 14 Jul 2020 07:01:14 GMT", "version": "v1" } ]
2020-11-11
[ [ "Kurkela", "Aleksi", "" ], [ "Taghavi", "Seyed Farid", "" ], [ "Wiedemann", "Urs Achim", "" ], [ "Wu", "Bin", "" ] ]
The observation of fluid-like behavior in nucleus-nucleus, proton-nucleus and high-multiplicity proton-proton collisions motivates systematic studies of how different measurements approach their fluid-dynamic limit. We have developed numerical methods to solve the ultra-relativistic Boltzmann equation for systems of arbitrary size and transverse geometry. Here, we apply these techniques for the first time to the study of azimuthal flow coefficients $v_n$ including non-linear mode-mode coupling and to an initial condition with realistic event-by-event fluctuations. We show how both linear and non-linear response coefficients extracted from $v_n$ develop as a function of opacity from free streaming to perfect fluidity. We note in particular that away from the fluid-dynamic limit, the signal strength of linear and non-linear response coefficients does not reduce uniformly, but that their hierarchy and relative size shows characteristic differences.
1606.05326
Ezequiel Alvarez
Ezequiel Alvarez (ICAS, Argentina), Leandro Da Rold (CAB, Argentina), Javier Mazzitelli (ICAS, Argentina) and Alejandro Szynkman (UNLP, Argentina)
A 750 GeV graviton and the Higgs as a pNGB
24 pages, 12 figures
null
null
ICAS 014/16
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the diphoton excess at 750 GeV reported by ATLAS and CMS, by assuming that it corresponds to a new spin-two resonant state. We model this state as a massive graviton in a two-site model. We show that the very stringent bounds from $VV$ final states can be evaded naturally by considering that the Higgs is a pseudo Nambu-Goldstone boson. In this case the couplings of the graviton to the longitudinal electroweak gauge bosons can be parametrically suppressed. On the other hand, partial compositeness allows to suppress the leptonic channels. We compute loop-induced contributions to the graviton couplings by the presence of the SM third generation of quarks and composite partners of the SM fermions and obtain that they are not important. We find that the diphoton signal and the experimental constraints from other decay channels can be reproduced in a large and natural region of the parameter space of the theory.
[ { "created": "Thu, 16 Jun 2016 19:38:27 GMT", "version": "v1" } ]
2016-06-17
[ [ "Alvarez", "Ezequiel", "", "ICAS, Argentina" ], [ "Da Rold", "Leandro", "", "CAB, Argentina" ], [ "Mazzitelli", "Javier", "", "ICAS, Argentina" ], [ "Szynkman", "Alejandro", "", "UNLP, Argentina" ] ]
We study the diphoton excess at 750 GeV reported by ATLAS and CMS, by assuming that it corresponds to a new spin-two resonant state. We model this state as a massive graviton in a two-site model. We show that the very stringent bounds from $VV$ final states can be evaded naturally by considering that the Higgs is a pseudo Nambu-Goldstone boson. In this case the couplings of the graviton to the longitudinal electroweak gauge bosons can be parametrically suppressed. On the other hand, partial compositeness allows to suppress the leptonic channels. We compute loop-induced contributions to the graviton couplings by the presence of the SM third generation of quarks and composite partners of the SM fermions and obtain that they are not important. We find that the diphoton signal and the experimental constraints from other decay channels can be reproduced in a large and natural region of the parameter space of the theory.
1612.01969
Roman Pasechnik
Eduardo Basso, Claude Bourrely, Roman Pasechnik and Jacques Soffer
The landscape of $W^{\pm}$ and $Z$ bosons produced in $pp$ collisions up to LHC energies
16 pages, 8 figures; discussion extended, typos fixed; published version
null
10.1016/j.nuclphysa.2017.06.035
LU TP 16-63
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a selection of recent experimental results on electroweak $W^{\pm},\,Z$ gauge boson production in $pp$ collisions at BNL RHIC and CERN LHC energies in comparison to prediction of perturbative QCD calculations based on different sets of NLO parton distribution functions including the statistical PDF model known from fits to the DIS data. We show that the current statistical PDF parameterisation (fitted to the DIS data only) underestimates the LHC data on $W^{\pm},\,Z$ gauge boson production cross sections at the NLO by about 20\%. This suggests that there is a need to refit the parameters of the statistical PDF including the latest LHC data.
[ { "created": "Tue, 6 Dec 2016 19:58:35 GMT", "version": "v1" }, { "created": "Sat, 10 Dec 2016 22:08:17 GMT", "version": "v2" }, { "created": "Wed, 21 Jun 2017 01:21:05 GMT", "version": "v3" } ]
2017-06-22
[ [ "Basso", "Eduardo", "" ], [ "Bourrely", "Claude", "" ], [ "Pasechnik", "Roman", "" ], [ "Soffer", "Jacques", "" ] ]
We consider a selection of recent experimental results on electroweak $W^{\pm},\,Z$ gauge boson production in $pp$ collisions at BNL RHIC and CERN LHC energies in comparison to prediction of perturbative QCD calculations based on different sets of NLO parton distribution functions including the statistical PDF model known from fits to the DIS data. We show that the current statistical PDF parameterisation (fitted to the DIS data only) underestimates the LHC data on $W^{\pm},\,Z$ gauge boson production cross sections at the NLO by about 20\%. This suggests that there is a need to refit the parameters of the statistical PDF including the latest LHC data.
1911.00479
Herschel A. Chawdhry
Herschel A. Chawdhry, Micha{\l} Czakon, Alexander Mitov and Rene Poncelet
NNLO QCD corrections to three-photon production at the LHC
20 pages, 6 figures. v2: published version
JHEP 2002 (2020) 057
10.1007/JHEP02(2020)057
Cavendish-HEP-19/17, TTK-19-45, P3H-19-041
hep-ph hep-ex hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the NNLO QCD corrections to three-photon production at the LHC. This is the first NNLO QCD calculation for a $2\to 3$ process. Our calculation is exact, except for the scale-independent part of the two-loop finite remainder which is included in the leading color approximation. We estimate the size of the missing two-loop corrections and find them to be phenomenologically negligible. We compare our predictions with available 8 TeV measurement from the ATLAS collaboration. We find that the inclusion of the NNLO corrections eliminates the existing significant discrepancy with respect to NLO QCD predictions, paving the way for precision phenomenology in this process.
[ { "created": "Fri, 1 Nov 2019 17:43:35 GMT", "version": "v1" }, { "created": "Wed, 26 Feb 2020 15:56:14 GMT", "version": "v2" } ]
2020-02-27
[ [ "Chawdhry", "Herschel A.", "" ], [ "Czakon", "Michał", "" ], [ "Mitov", "Alexander", "" ], [ "Poncelet", "Rene", "" ] ]
We compute the NNLO QCD corrections to three-photon production at the LHC. This is the first NNLO QCD calculation for a $2\to 3$ process. Our calculation is exact, except for the scale-independent part of the two-loop finite remainder which is included in the leading color approximation. We estimate the size of the missing two-loop corrections and find them to be phenomenologically negligible. We compare our predictions with available 8 TeV measurement from the ATLAS collaboration. We find that the inclusion of the NNLO corrections eliminates the existing significant discrepancy with respect to NLO QCD predictions, paving the way for precision phenomenology in this process.
1611.05354
Jorge de Blas Mateo
Jorge de Blas, Marco Ciuchini, Enrico Franco, Satoshi Mishima, Maurizio Pierini, Laura Reina, Luca Silvestrini
Electroweak precision constraints at present and future colliders
6 + 1 pages, 4 figures, 6 tables. Minor corrections. Contribution to the Proceedings of the 38th International Conference on High Energy Physics, 3-10 August 2016, Chicago, U.S.A
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the global fit to electroweak precision observables in the Standard Model and present model-independent bounds on several general new physics scenarios. We present a projection of the fit based on the expected experimental improvements at future $e^+ e^-$ colliders, and compare the constraining power of some of the different experiments that have been proposed. All results have been obtained with the HEPfit code.
[ { "created": "Wed, 16 Nov 2016 16:45:46 GMT", "version": "v1" }, { "created": "Sun, 26 Feb 2017 11:56:48 GMT", "version": "v2" } ]
2017-02-28
[ [ "de Blas", "Jorge", "" ], [ "Ciuchini", "Marco", "" ], [ "Franco", "Enrico", "" ], [ "Mishima", "Satoshi", "" ], [ "Pierini", "Maurizio", "" ], [ "Reina", "Laura", "" ], [ "Silvestrini", "Luca", "" ] ]
We revisit the global fit to electroweak precision observables in the Standard Model and present model-independent bounds on several general new physics scenarios. We present a projection of the fit based on the expected experimental improvements at future $e^+ e^-$ colliders, and compare the constraining power of some of the different experiments that have been proposed. All results have been obtained with the HEPfit code.
hep-ph/9907243
David London
Ahmed Ali and David London
Precision Flavour Physics and Supersymmetry
35 pages, 12 figures
Phys.Rept.320:79-106,1999
10.1016/S0370-1573(99)00075-7
DESY 99-083, UdeM-GPP-TH-99-60
hep-ph
null
We review the salient features of a comparative study of the profile of the CKM unitarity triangle, and the resulting CP-violating phases $\alpha$, $\beta$ and $\gamma$ in B decays, in the standard model and in several variants of the minimal supersymmetric standard model (MSSM), reported recently by us. These theories are characterized by a single phase in the quark flavour mixing matrix and give rise to well-defined contributions in the flavour-changing-neutral-current transitions in K and B decays. We analyse the supersymmetric contributions to the mass differences in the Bd-Bd(bar) and Bs-Bs(bar) systems, $\Delta M_d$ and $\Delta M_s$, respectively, and to the CP-violating quantity $|epsilon|$ in K decays. Our analysis shows that the predicted ranges of $\beta$ in the standard model and in MSSM models are very similar. However, precise measurements at B-factories and hadron machines may be able to distinguish these theories in terms of the other two CP-violating phases $\alpha$ and $\gamma$. (Contribution to the Festschrift for L.B. Okun, to appear in a special issue of Physics Reports, eds. V.L. Telegdi and K. Winter)
[ { "created": "Mon, 5 Jul 1999 19:34:21 GMT", "version": "v1" } ]
2010-11-23
[ [ "Ali", "Ahmed", "" ], [ "London", "David", "" ] ]
We review the salient features of a comparative study of the profile of the CKM unitarity triangle, and the resulting CP-violating phases $\alpha$, $\beta$ and $\gamma$ in B decays, in the standard model and in several variants of the minimal supersymmetric standard model (MSSM), reported recently by us. These theories are characterized by a single phase in the quark flavour mixing matrix and give rise to well-defined contributions in the flavour-changing-neutral-current transitions in K and B decays. We analyse the supersymmetric contributions to the mass differences in the Bd-Bd(bar) and Bs-Bs(bar) systems, $\Delta M_d$ and $\Delta M_s$, respectively, and to the CP-violating quantity $|epsilon|$ in K decays. Our analysis shows that the predicted ranges of $\beta$ in the standard model and in MSSM models are very similar. However, precise measurements at B-factories and hadron machines may be able to distinguish these theories in terms of the other two CP-violating phases $\alpha$ and $\gamma$. (Contribution to the Festschrift for L.B. Okun, to appear in a special issue of Physics Reports, eds. V.L. Telegdi and K. Winter)
2009.09228
Rui Santos
Da Huang, Ant\'onio P. Morais, Rui Santos
CP Violating $hW^+W^-$ Coupling in the Standard Model and Beyond
19 pages, 4 figures
null
10.1007/JHEP01(2021)168
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inspired by the recent development in determining the property of the observed Higgs boson, we explore the $CP$-violating (CPV) $- c_{\rm CPV} h W^{+\, \mu\nu}\tilde{W}^{-}_{\mu\nu}/v$ coupling in the Standard Model (SM) and beyond, where $W^{\pm \, \mu \nu}$ and $\tilde{W}^{\pm\,\mu\nu}$ denote the $W$-boson field strength and its dual. To begin with, we show that the leading-order SM contribution to this CPV vertex appears at two-loop level. By summing over the quark flavor indices in the two loop integrals analytically, we can estimate the order of the corresponding Wilson coefficient to be $c^{\rm SM}_{\rm CPV} \sim {\cal O}(10^{-23})$, which is obviously too small to be probed at the LHC and planned future colliders. Then we investigate this CPV $hW^+ W^-$ interaction in two Beyond the Standard Model benchmark models: the left-right model and the complex 2-Higgs doublet model (C2HDM). Unlike what happens for the SM, the dominant contributions in both models arise at the one-loop level, and the corresponding Wilson coefficient can be as large as of ${\cal O}(10^{-9})$ in the former model and of ${\cal O}(10^{-3})$ for the latter. In light of such a large CPV effect in the $hW^+W^-$ coupling, we also give the formulae for the leading one-loop contribution to the related CPV $hZZ$ effective operator in the C2HDM. The order of magnitude of the Wilson coefficients in the C2HDM may be within reach of the high-luminosity LHC or planned future colliders.
[ { "created": "Sat, 19 Sep 2020 13:32:51 GMT", "version": "v1" } ]
2021-02-24
[ [ "Huang", "Da", "" ], [ "Morais", "António P.", "" ], [ "Santos", "Rui", "" ] ]
Inspired by the recent development in determining the property of the observed Higgs boson, we explore the $CP$-violating (CPV) $- c_{\rm CPV} h W^{+\, \mu\nu}\tilde{W}^{-}_{\mu\nu}/v$ coupling in the Standard Model (SM) and beyond, where $W^{\pm \, \mu \nu}$ and $\tilde{W}^{\pm\,\mu\nu}$ denote the $W$-boson field strength and its dual. To begin with, we show that the leading-order SM contribution to this CPV vertex appears at two-loop level. By summing over the quark flavor indices in the two loop integrals analytically, we can estimate the order of the corresponding Wilson coefficient to be $c^{\rm SM}_{\rm CPV} \sim {\cal O}(10^{-23})$, which is obviously too small to be probed at the LHC and planned future colliders. Then we investigate this CPV $hW^+ W^-$ interaction in two Beyond the Standard Model benchmark models: the left-right model and the complex 2-Higgs doublet model (C2HDM). Unlike what happens for the SM, the dominant contributions in both models arise at the one-loop level, and the corresponding Wilson coefficient can be as large as of ${\cal O}(10^{-9})$ in the former model and of ${\cal O}(10^{-3})$ for the latter. In light of such a large CPV effect in the $hW^+W^-$ coupling, we also give the formulae for the leading one-loop contribution to the related CPV $hZZ$ effective operator in the C2HDM. The order of magnitude of the Wilson coefficients in the C2HDM may be within reach of the high-luminosity LHC or planned future colliders.
0705.4468
Guang-You Qin
G.Y. Qin, J. Ruppert, S. Turbide, C. Gale and S. Jeon
Nuclear Suppression of Jets and R_AA at the LHC
2 pages, 1 figure, contributed to Workshop on Heavy Ion Collisions at the LHC: Last Call for Predictions, Geneva, Switzerland, 14 May - 8 Jun 2007
null
null
null
hep-ph nucl-th
null
The nuclear modification factor R_AA for charged hadron production at the LHC is predicted from jet energy loss induced by gluon bremsstrahlung. The Arnold, Moore, and Yaffe formalism is used, together with an ideal hydrodynamical model.
[ { "created": "Wed, 30 May 2007 21:11:27 GMT", "version": "v1" } ]
2007-06-13
[ [ "Qin", "G. Y.", "" ], [ "Ruppert", "J.", "" ], [ "Turbide", "S.", "" ], [ "Gale", "C.", "" ], [ "Jeon", "S.", "" ] ]
The nuclear modification factor R_AA for charged hadron production at the LHC is predicted from jet energy loss induced by gluon bremsstrahlung. The Arnold, Moore, and Yaffe formalism is used, together with an ideal hydrodynamical model.
1001.4801
Kyoungchul Kong
Kyoungchul Kong, Konstantin Matchev, Geraldine Servant
Extra Dimensions at the LHC
33 pages, 17 figures
From `Particle Dark Matter: Observations, Models and Searches' edited by Gianfranco Bertone. Chapter 15, pp. 306-324, Hardback ISBN 9780521763684
null
CERN-PH-TH/2010-014
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the motivation and the phenomenology of models with either flat or warped extra dimensions. We describe the typical mass spectrum and discovery signatures of such models at the LHC. We also review several proposed methods for discriminating the usual low-energy supersymmetry from a model with flat (universal) extra dimensions. (For the official website of the book, see http://cambridge.org/us/catalogue/catalogue.asp?isbn=9780521763684 .)
[ { "created": "Tue, 26 Jan 2010 21:28:58 GMT", "version": "v1" } ]
2010-01-28
[ [ "Kong", "Kyoungchul", "" ], [ "Matchev", "Konstantin", "" ], [ "Servant", "Geraldine", "" ] ]
We discuss the motivation and the phenomenology of models with either flat or warped extra dimensions. We describe the typical mass spectrum and discovery signatures of such models at the LHC. We also review several proposed methods for discriminating the usual low-energy supersymmetry from a model with flat (universal) extra dimensions. (For the official website of the book, see http://cambridge.org/us/catalogue/catalogue.asp?isbn=9780521763684 .)
hep-ph/0310250
Alexander Parkhomenko
A. Ali (CERN), A.Ya. Parkhomenko (Univ. Bern)
The $\eta^\prime g^* g^{(*)}$ Vertex Function in Perturbative QCD and $\eta^\prime$-Meson Mass Effects
4 pages, 2 figures, use svjour.cls and svepj.clo; talk given at the International Europhysics Conference on High-Energy Physics (HEP 2003), 17-23 July 2003, Aachen, Germany. Title changed
null
null
CERN-TH/2003-253
hep-ph
null
The $\eta^\prime g^* g^{(*)}$ effective vertex function (EVF) is calculated in the QCD hard-scattering approach, taking into account the $\eta^\prime$-meson mass. We work in the approximation in which only one non-leading Gegenbauer moment in both the quark-antiquark and gluonic light-cone distribution amplitude for the $\eta^\prime$-meson is kept. The EVF with one off-shell gluon is shown to have the form $F_{\eta^\prime g^* g} (q_1^2, 0, m_{\eta^\prime}^2) = m_{\eta^\prime}^2 H(q_1^2)/(q_1^2 - m_{\eta^\prime}^2)$, valid for $|q_1^2| > m_{\eta^\prime}^2$. An interpolating formulae for the EVF in the space-like region of the virtuality $q_1^2$, which satisfies the QCD-anomaly normalization for on-shell gluons and the perturbative-QCD result for the gluon virtuality $|q_1^2| \gtrsim 2 GeV^2$, is also presented.
[ { "created": "Tue, 21 Oct 2003 16:52:41 GMT", "version": "v1" }, { "created": "Wed, 22 Oct 2003 17:07:40 GMT", "version": "v2" } ]
2007-05-23
[ [ "Ali", "A.", "", "CERN" ], [ "Parkhomenko", "A. Ya.", "", "Univ. Bern" ] ]
The $\eta^\prime g^* g^{(*)}$ effective vertex function (EVF) is calculated in the QCD hard-scattering approach, taking into account the $\eta^\prime$-meson mass. We work in the approximation in which only one non-leading Gegenbauer moment in both the quark-antiquark and gluonic light-cone distribution amplitude for the $\eta^\prime$-meson is kept. The EVF with one off-shell gluon is shown to have the form $F_{\eta^\prime g^* g} (q_1^2, 0, m_{\eta^\prime}^2) = m_{\eta^\prime}^2 H(q_1^2)/(q_1^2 - m_{\eta^\prime}^2)$, valid for $|q_1^2| > m_{\eta^\prime}^2$. An interpolating formulae for the EVF in the space-like region of the virtuality $q_1^2$, which satisfies the QCD-anomaly normalization for on-shell gluons and the perturbative-QCD result for the gluon virtuality $|q_1^2| \gtrsim 2 GeV^2$, is also presented.
1507.01395
Arghya Choudhury
Manimala Chakraborti, Utpal Chattopadhyay, Arghya Choudhury, Amitava Datta, Sujoy Poddar
Reduced LHC constraints for higgsino-like heavier electroweakinos
55 pages, 13 figures, 10 tables. Version published in JHEP
JHEP 11 (2015) 050
10.1007/JHEP11(2015)050
HRI-RECAPP-2015-014
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
As a sequel to our earlier work on wino-dominated $\tilde \chi_1^{\pm}$ and $\tilde \chi_2^{0}$ (wino models), we focus on the pMSSM models where $\tilde \chi_1^{\pm}$ and $\tilde \chi_{2,3}^{0}$ are either higgsino dominated (higgsino models) or admixtures of significant amount of higgsino and wino components (mixed models), with or without light sleptons. The LHC constraints in the trilepton channel are significantly weaker even in the presence of light sleptons, especially in the higgsino models, compared to those mostly studied by the LHC collaborations with wino-dominated $\tilde \chi_1^{\pm}$ and $\tilde \chi_2^{0}$. The modes $\tilde \chi_{2,3}^{0}\rightarrow h~\tilde\chi_1^{0}$ with large branching ratios (BRs) are more common in the higgsino models and may produce spectacular signal in the LHC Run-II. In a variety of higgsino and mixed models we have delineated the allowed parameter space due to the LHC constraints, the observed Dark Matter (DM) relic density of the universe, which gets contributions from many novel DM producing mechanisms i.e., the annihilation/coannihilation processes that lead to the correct range of relic density, and the precise measurement of the anomalous magnetic moment of the muon. In the higgsino models many new DM producing mechanisms, which are not allowed in the wino models, open up. We have also explored the prospects of direct and indirect detection of DM in the context of the LUX and IceCube experiments respectively. In an extended model having only light gluinos in addition to the electroweak sparticles, the gluinos decay into final states with multiple taggable b-jets with very large BRs. As a consequence, the existing ATLAS data in the $0l$ + jets (3b) + $E\!\!\!\!/_T$ channel provide the best limit on $m_{\tilde g}$ ($\approx$ 1.3 TeV). Several novel signatures of higgsino models for LHC Run-II and ILC have been identified.
[ { "created": "Mon, 6 Jul 2015 11:24:03 GMT", "version": "v1" }, { "created": "Wed, 18 Nov 2015 15:04:26 GMT", "version": "v2" } ]
2015-11-19
[ [ "Chakraborti", "Manimala", "" ], [ "Chattopadhyay", "Utpal", "" ], [ "Choudhury", "Arghya", "" ], [ "Datta", "Amitava", "" ], [ "Poddar", "Sujoy", "" ] ]
As a sequel to our earlier work on wino-dominated $\tilde \chi_1^{\pm}$ and $\tilde \chi_2^{0}$ (wino models), we focus on the pMSSM models where $\tilde \chi_1^{\pm}$ and $\tilde \chi_{2,3}^{0}$ are either higgsino dominated (higgsino models) or admixtures of significant amount of higgsino and wino components (mixed models), with or without light sleptons. The LHC constraints in the trilepton channel are significantly weaker even in the presence of light sleptons, especially in the higgsino models, compared to those mostly studied by the LHC collaborations with wino-dominated $\tilde \chi_1^{\pm}$ and $\tilde \chi_2^{0}$. The modes $\tilde \chi_{2,3}^{0}\rightarrow h~\tilde\chi_1^{0}$ with large branching ratios (BRs) are more common in the higgsino models and may produce spectacular signal in the LHC Run-II. In a variety of higgsino and mixed models we have delineated the allowed parameter space due to the LHC constraints, the observed Dark Matter (DM) relic density of the universe, which gets contributions from many novel DM producing mechanisms i.e., the annihilation/coannihilation processes that lead to the correct range of relic density, and the precise measurement of the anomalous magnetic moment of the muon. In the higgsino models many new DM producing mechanisms, which are not allowed in the wino models, open up. We have also explored the prospects of direct and indirect detection of DM in the context of the LUX and IceCube experiments respectively. In an extended model having only light gluinos in addition to the electroweak sparticles, the gluinos decay into final states with multiple taggable b-jets with very large BRs. As a consequence, the existing ATLAS data in the $0l$ + jets (3b) + $E\!\!\!\!/_T$ channel provide the best limit on $m_{\tilde g}$ ($\approx$ 1.3 TeV). Several novel signatures of higgsino models for LHC Run-II and ILC have been identified.
hep-ph/9306299
Keh-Fei Liu
Keh-Fei Liu and Shao-Jing Dong
Origin of Difference between $\overline{d}$ and $\overline{u}$ Partons in the Nucleon
8 Pages, 5 ps figures included in part 2, UK/93-02
Phys.Rev.Lett.72:1790-1793,1994
10.1103/PhysRevLett.72.1790
null
hep-ph hep-lat
null
Using the Euclidean path-integral formulation for the hadronic tensor, we show that the violation of the Gottfried sum rule does not come from the disconnected quark-loop insertion. Rather, it comes from the connected (quark line) insertion involving quarks propagating in the backward time direction. We demonstrate this by studying sum rules in terms of the scalar and axial- vector matrix elements in lattice gauge calculations. The effects of eliminating backward time propagation are presented.
[ { "created": "Mon, 21 Jun 1993 19:05:27 GMT", "version": "v1" } ]
2011-02-01
[ [ "Liu", "Keh-Fei", "" ], [ "Dong", "Shao-Jing", "" ] ]
Using the Euclidean path-integral formulation for the hadronic tensor, we show that the violation of the Gottfried sum rule does not come from the disconnected quark-loop insertion. Rather, it comes from the connected (quark line) insertion involving quarks propagating in the backward time direction. We demonstrate this by studying sum rules in terms of the scalar and axial- vector matrix elements in lattice gauge calculations. The effects of eliminating backward time propagation are presented.
hep-ph/9508228
Jerry Franklin
Jerrold Franklin
The spin of the nucleon in its rest system
3 pages, Latex file with 5 uuencoded tar compressed PostScript figures
null
null
TUHE9581
hep-ph
null
The spin dependent structure functions, g$_{1p}$ of the proton and g$_{1n}$ of the neutron, calculated in the nucleon rest frame using a relativistic quark model wave function, are compared with recent experiments.
[ { "created": "Fri, 4 Aug 1995 02:09:15 GMT", "version": "v1" } ]
2016-09-01
[ [ "Franklin", "Jerrold", "" ] ]
The spin dependent structure functions, g$_{1p}$ of the proton and g$_{1n}$ of the neutron, calculated in the nucleon rest frame using a relativistic quark model wave function, are compared with recent experiments.
1110.1857
Alon Faraggi
Alon E. Faraggi
OPERA data and The Equivalence Postulate of Quantum Mechanics
8 pages. Standard LaTex. References added
null
10.1140/epjc/s10052-012-1944-y
LTH-924
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An interpretation of the recent results reported by the OPERA collaboration is that neutrinos propagation in vacuum exceeds the speed of light. It has been further been suggested that this interpretation can be attributed to the variation of the particle speed arising from the Relativistic Quantum Hamilton Jacobi Equation. I show that this is in general not the case. I derive an expression for the quantum correction to the instantaneous relativistic velocity in the framework of the relativistic quantum Hamilton-Jacobi equation, which is derived from the equivalence postulate of quantum mechanics. While the quantum correction does indicate deviations from the classical energy--momentum relation, it does not necessarily lead to superluminal speeds. The quantum correction found herein has a non-trivial dependence on the energy and mass of the particle, as well as on distance travelled. I speculate on other possible observational consequences of the equivalence postulate approach.
[ { "created": "Sun, 9 Oct 2011 16:58:57 GMT", "version": "v1" }, { "created": "Mon, 24 Oct 2011 08:16:21 GMT", "version": "v2" } ]
2015-05-30
[ [ "Faraggi", "Alon E.", "" ] ]
An interpretation of the recent results reported by the OPERA collaboration is that neutrinos propagation in vacuum exceeds the speed of light. It has been further been suggested that this interpretation can be attributed to the variation of the particle speed arising from the Relativistic Quantum Hamilton Jacobi Equation. I show that this is in general not the case. I derive an expression for the quantum correction to the instantaneous relativistic velocity in the framework of the relativistic quantum Hamilton-Jacobi equation, which is derived from the equivalence postulate of quantum mechanics. While the quantum correction does indicate deviations from the classical energy--momentum relation, it does not necessarily lead to superluminal speeds. The quantum correction found herein has a non-trivial dependence on the energy and mass of the particle, as well as on distance travelled. I speculate on other possible observational consequences of the equivalence postulate approach.
0704.2205
Maurizio Piai
Maurizio Piai
Vector mesons from AdS/TC to the LHC
24 pages, 5 figures
null
null
null
hep-ph
null
With the use of the AdS/CFT dictionary, a five-dimensional effective description of dynamical electro-weak symmetry breaking with walking behavior is constructed. The minimal model contains only two new parameters, the confinement scale and the effective coupling of the new strong sector. This parameter space is restricted by the precision electro-weak constraints and by the requirement that the five-dimensional coupling be perturbative (corresponding to the large-N regime in four-dimensional language). The lightest observable new states are a set of four nearly degenerate spin-1 states with the same quantum numbers as the standard-model electro-weak gauge bosons, and masses in the few TeV range. Their decay rate is dominated by two-fermion final states. The number of pp -> mu mu and pp -> mu nu events is studied as a function of the LHC integrated luminosity and of the two free parameters. Discovery at the LHC is possible over a significant part of the allowed parameter space up to masses of 4 TeV already with 10/fm of integrated luminosity.
[ { "created": "Tue, 17 Apr 2007 17:50:12 GMT", "version": "v1" } ]
2007-05-23
[ [ "Piai", "Maurizio", "" ] ]
With the use of the AdS/CFT dictionary, a five-dimensional effective description of dynamical electro-weak symmetry breaking with walking behavior is constructed. The minimal model contains only two new parameters, the confinement scale and the effective coupling of the new strong sector. This parameter space is restricted by the precision electro-weak constraints and by the requirement that the five-dimensional coupling be perturbative (corresponding to the large-N regime in four-dimensional language). The lightest observable new states are a set of four nearly degenerate spin-1 states with the same quantum numbers as the standard-model electro-weak gauge bosons, and masses in the few TeV range. Their decay rate is dominated by two-fermion final states. The number of pp -> mu mu and pp -> mu nu events is studied as a function of the LHC integrated luminosity and of the two free parameters. Discovery at the LHC is possible over a significant part of the allowed parameter space up to masses of 4 TeV already with 10/fm of integrated luminosity.
hep-ph/0201016
John McDonald
John McDonald (Liverpool)
F-Term Hybrid Inflation, the \eta-problem and Extra Dimensions
11 pages LaTeX. Correction to review discussion. Results unchanged
JHEP 0212 (2002) 029
10.1088/1126-6708/2002/12/029
null
hep-ph astro-ph
null
F-term hybrid inflation models in the context of supergravity generically have corrections to the inflaton mass squared of the order of H^{2} (the \eta-problem). In addition they have a problem with large deviations of the spectrum of density perturbations from scale-invariance due to non-renormalizable corrections to the superpotential. Here we show that an increase of the expansion rate at large energy densities relative to that in conventional d=4 cosmology, as suggested by the single brane Randall-Sundrum scenario with an uncompactified extra dimension, can naturally solve the \eta problem. This requires that the d=5 Planck mass satisfies M_{5} < 10^{16} GeV. In addition, the scale-invariance of the density perturbation spectrum can be generally protected from Planck-suppressed superpotential corrections if M_{5} < 10^{10} \GeV
[ { "created": "Fri, 4 Jan 2002 15:25:37 GMT", "version": "v1" }, { "created": "Sat, 5 Jan 2002 14:19:06 GMT", "version": "v2" }, { "created": "Wed, 30 Jan 2002 16:34:59 GMT", "version": "v3" }, { "created": "Mon, 17 Jun 2002 22:51:23 GMT", "version": "v4" }, { "cre...
2009-11-07
[ [ "McDonald", "John", "", "Liverpool" ] ]
F-term hybrid inflation models in the context of supergravity generically have corrections to the inflaton mass squared of the order of H^{2} (the \eta-problem). In addition they have a problem with large deviations of the spectrum of density perturbations from scale-invariance due to non-renormalizable corrections to the superpotential. Here we show that an increase of the expansion rate at large energy densities relative to that in conventional d=4 cosmology, as suggested by the single brane Randall-Sundrum scenario with an uncompactified extra dimension, can naturally solve the \eta problem. This requires that the d=5 Planck mass satisfies M_{5} < 10^{16} GeV. In addition, the scale-invariance of the density perturbation spectrum can be generally protected from Planck-suppressed superpotential corrections if M_{5} < 10^{10} \GeV
hep-ph/9912519
Shuqian Ying
S. Ying (Fudan Univ.)
Color superconductivity and its electromagnetic manifestation
27 pages, 7 figures in eps references added and wordings changed
null
null
FDU-23-12-99
hep-ph hep-th nucl-th
null
A collection of the physical observables, related to the electromagnetic properties of a nucleon, to investigate the non--perturbative quantum fluctuations in the strong interaction vacuum state under the influence of at least one close by (in energy density) color superconducting phase found in several QCD motivated model calculations, are studied. It is shown that the spontaneous breaking of the electromagnetic gauge symmetry in the color superconducting phase of strong interaction can result in relatively clean signals in high energy processes, especially in the semi-leptonic deep inelastic scattering ones, due to a kind of electromagnetic induced strong interaction. A new type of mechanism, which is a generalization of the Higgs one, through which the local electromagnetic gauge symmetry is spontaneously broken by a spontaneous breaking of the global baryon (nucleon) number conservation, is revealed. A model independent assessment of the question of how far is the color superconducting phase of the strong interaction from its vacuum phase is made by studying currently available experimental data on the electromagnetic responses of a nucleon at high energies. It is shown that based on our current knowledge about a nucleon, it is quite likely that there is at least one color superconducting phase for the strong interaction that is close enough to the vacuum state so that its effects can even be seen in high energy processes besides heavy ion collisions.
[ { "created": "Tue, 28 Dec 1999 03:41:55 GMT", "version": "v1" }, { "created": "Tue, 4 Jul 2000 12:42:03 GMT", "version": "v2" } ]
2007-05-23
[ [ "Ying", "S.", "", "Fudan Univ." ] ]
A collection of the physical observables, related to the electromagnetic properties of a nucleon, to investigate the non--perturbative quantum fluctuations in the strong interaction vacuum state under the influence of at least one close by (in energy density) color superconducting phase found in several QCD motivated model calculations, are studied. It is shown that the spontaneous breaking of the electromagnetic gauge symmetry in the color superconducting phase of strong interaction can result in relatively clean signals in high energy processes, especially in the semi-leptonic deep inelastic scattering ones, due to a kind of electromagnetic induced strong interaction. A new type of mechanism, which is a generalization of the Higgs one, through which the local electromagnetic gauge symmetry is spontaneously broken by a spontaneous breaking of the global baryon (nucleon) number conservation, is revealed. A model independent assessment of the question of how far is the color superconducting phase of the strong interaction from its vacuum phase is made by studying currently available experimental data on the electromagnetic responses of a nucleon at high energies. It is shown that based on our current knowledge about a nucleon, it is quite likely that there is at least one color superconducting phase for the strong interaction that is close enough to the vacuum state so that its effects can even be seen in high energy processes besides heavy ion collisions.
hep-ph/9805386
Teshima Tadayuki
T. Teshima and T. Sakai
Atmospheric neutrino oscillations in three-flavor neutrinos
21 pages, LaTeX
Prog.Theor.Phys. 101 (1999) 147
10.1143/PTP.101.147
CU-TP/98-05
hep-ph
null
We analyzed the atmospheric neutrino experiments of SuperKamiokande including zenith angle dependence's using the three-flavor neutrino framework with the hierarchy m^2_1 \approx m^2_2<<m^2_3. Taking into account the terrestrial, solar neutrino experimental data and the atmospheric neutrino experiments including the sub-GeV and multi-GeV data in SuperKamiokande, large angle solution in the solar neutrino experiments is favored and the range of the mass parameter Deltam^2_{23} is restricted between 0.08eV^2 - 2eV^2. Allowed regions of mixing parameters are (theta_{13}<4degree, 27degree<theta_{23}< 32degree) for Delta m_{23}^2=1eV^2 and (theta_{13}<3degree, 28degree<theta_{23} <33degree) for Deltam_{23}^2=0.1 eV^2.
[ { "created": "Wed, 20 May 1998 08:24:19 GMT", "version": "v1" } ]
2009-10-31
[ [ "Teshima", "T.", "" ], [ "Sakai", "T.", "" ] ]
We analyzed the atmospheric neutrino experiments of SuperKamiokande including zenith angle dependence's using the three-flavor neutrino framework with the hierarchy m^2_1 \approx m^2_2<<m^2_3. Taking into account the terrestrial, solar neutrino experimental data and the atmospheric neutrino experiments including the sub-GeV and multi-GeV data in SuperKamiokande, large angle solution in the solar neutrino experiments is favored and the range of the mass parameter Deltam^2_{23} is restricted between 0.08eV^2 - 2eV^2. Allowed regions of mixing parameters are (theta_{13}<4degree, 27degree<theta_{23}< 32degree) for Delta m_{23}^2=1eV^2 and (theta_{13}<3degree, 28degree<theta_{23} <33degree) for Deltam_{23}^2=0.1 eV^2.
1901.07177
Arkadii Kozhevnikov
A.A. Kozhevnikov
Dynamical analysis of the $X$ resonance contributions to the decay $J/\psi\to\gamma X\to\gamma\phi\phi$
11 pages, 8 figures
Phys. Rev. D99, 014019 (2019)
10.1103/PhysRevD.99.014019
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The dynamics of the $J^{PC}=0^{-+}$, $0^{++}$, and $2^{++}$ resonance contributions to the decay $J/\psi\to\gamma X(J^{PC})\to\gamma\phi\phi$ is analysed using the data obtained by BESIII collaboration. The effective coupling constants parameterising invariant amplitudes of the transitions $J/\psi\to\gamma X(J^{PC})$ and $X(J^{PC})\to\phi\phi$ and masses of $X(J^{PC})$ resonances are found from the fits. They are used for evaluation of the branching fractions $B_{X(J^{PC})\to\phi\phi}$, relative branching fractions $B_{J/\psi\to\gamma X(J^{PC})\to\gamma\phi\phi}$, and for obtaining the photon angular distributions.
[ { "created": "Tue, 22 Jan 2019 05:34:54 GMT", "version": "v1" } ]
2019-01-23
[ [ "Kozhevnikov", "A. A.", "" ] ]
The dynamics of the $J^{PC}=0^{-+}$, $0^{++}$, and $2^{++}$ resonance contributions to the decay $J/\psi\to\gamma X(J^{PC})\to\gamma\phi\phi$ is analysed using the data obtained by BESIII collaboration. The effective coupling constants parameterising invariant amplitudes of the transitions $J/\psi\to\gamma X(J^{PC})$ and $X(J^{PC})\to\phi\phi$ and masses of $X(J^{PC})$ resonances are found from the fits. They are used for evaluation of the branching fractions $B_{X(J^{PC})\to\phi\phi}$, relative branching fractions $B_{J/\psi\to\gamma X(J^{PC})\to\gamma\phi\phi}$, and for obtaining the photon angular distributions.
hep-ph/0701142
G\"oran F\"aldt
G\"oran F\"aldt
Pion polarisabilities and bremsstrahlung
21 pages
Phys.Rev.C76:014608,2007
10.1103/PhysRevC.76.014608
null
hep-ph
null
A model for high-energy, small-angle pion-nucleus bremsstrahlung, $ \pi^- +A\to\pi^- +\gamma +A$,is developed within the Glauber diffraction theory. Special attention is focussed on the possibility of measuring the pion polarisability in such reactions. That is the case under the Coulomb peak provided the bremsstrahlung photon carries practically all the energy of the incident pion. Only radiation from external legs is considered.
[ { "created": "Thu, 18 Jan 2007 12:44:16 GMT", "version": "v1" } ]
2008-11-26
[ [ "Fäldt", "Göran", "" ] ]
A model for high-energy, small-angle pion-nucleus bremsstrahlung, $ \pi^- +A\to\pi^- +\gamma +A$,is developed within the Glauber diffraction theory. Special attention is focussed on the possibility of measuring the pion polarisability in such reactions. That is the case under the Coulomb peak provided the bremsstrahlung photon carries practically all the energy of the incident pion. Only radiation from external legs is considered.
1806.04376
Yun Guo
Yun Guo, Lihua Dong, Jisi Pan and Manoel R. Moldes
Modeling the nonperturbative contributions to the complex heavy-quark potential
final version in PRD
Phys. Rev. D 100, 036011 (2019)
10.1103/PhysRevD.100.036011
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we construct a simple model for the complex heavy quark potential which is defined through the Fourier transform of the static gluon propagator. Besides the hard thermal loop resummed contribution, the gluon propagator also includes a non-perturbative term induced by the dimension two gluon condensate. Within the framework of thermal field theory, the real and imaginary parts of the heavy quark potential are determined in a consistent way without resorting to any extra assumption as long as the exact form of the retarded/advanced gluon propagator is specified. The resulting potential model has the desired asymptotic behaviors and reproduces the data from lattice simulation reasonably well. By presenting a direct comparison with other complex potential models on the market, we find the one proposed in this work shows a significant improvement on the description of the lattice results, especially for the imaginary part of the potential, in a temperature region relevant to quarkonium studies.
[ { "created": "Tue, 12 Jun 2018 07:58:36 GMT", "version": "v1" }, { "created": "Tue, 7 May 2019 10:24:06 GMT", "version": "v2" }, { "created": "Tue, 3 Sep 2019 01:45:36 GMT", "version": "v3" } ]
2019-09-04
[ [ "Guo", "Yun", "" ], [ "Dong", "Lihua", "" ], [ "Pan", "Jisi", "" ], [ "Moldes", "Manoel R.", "" ] ]
In this paper, we construct a simple model for the complex heavy quark potential which is defined through the Fourier transform of the static gluon propagator. Besides the hard thermal loop resummed contribution, the gluon propagator also includes a non-perturbative term induced by the dimension two gluon condensate. Within the framework of thermal field theory, the real and imaginary parts of the heavy quark potential are determined in a consistent way without resorting to any extra assumption as long as the exact form of the retarded/advanced gluon propagator is specified. The resulting potential model has the desired asymptotic behaviors and reproduces the data from lattice simulation reasonably well. By presenting a direct comparison with other complex potential models on the market, we find the one proposed in this work shows a significant improvement on the description of the lattice results, especially for the imaginary part of the potential, in a temperature region relevant to quarkonium studies.
2107.05632
Matthew Kelsey
Matthew Kelsey, Reynier Cruz-Torres, Xin Dong, Yuanjing Ji, Sooraj Radhakrishnan, Ernst Sichtermann
Constraints on Gluon Distribution Functions in the Nucleon and Nucleus from Open Charm Hadron Production at the Electron-Ion Collider
null
Phys. Rev. D 104, 054002 (2021)
10.1103/PhysRevD.104.054002
null
hep-ph hep-ex nucl-ex
http://creativecommons.org/licenses/by/4.0/
The Electron-Ion Collider (EIC) at Brookhaven National Laboratory will be a precision Quantum Chromodynamics machine that will enable a vast physics program with electron+proton/ion collisions across a broad center-of-mass range. Measurements of hard probes such as heavy flavor in deep inelastic scatterings will be an essential component to the EIC physics program and are one of the detector R\&D driving aspects. In this paper we study the projected statistical precision of open charm hadron production through exclusive hadronic channel reconstruction with a silicon detector concept currently being developed using a PYTHIA-based simulation. We further study the impact of possible intrinsic charm in the proton on projected data, and estimate the constraint on the nuclear gluon parton distribution function (PDF) from the charm structure functions $F_{2}^{c\overline{c}}$ in $e$+Au collisions using a Bayesian PDF re-weighting technique. Our studies show the EIC will be capable delivering an unprecedented measurement of charm hadron production across a broad kinematic region and will provide strong constraints to both intrinsic charm and nuclear gluon PDFs.
[ { "created": "Sun, 11 Jul 2021 16:40:37 GMT", "version": "v1" }, { "created": "Tue, 3 Aug 2021 17:42:23 GMT", "version": "v2" }, { "created": "Tue, 12 Oct 2021 17:46:41 GMT", "version": "v3" } ]
2021-10-13
[ [ "Kelsey", "Matthew", "" ], [ "Cruz-Torres", "Reynier", "" ], [ "Dong", "Xin", "" ], [ "Ji", "Yuanjing", "" ], [ "Radhakrishnan", "Sooraj", "" ], [ "Sichtermann", "Ernst", "" ] ]
The Electron-Ion Collider (EIC) at Brookhaven National Laboratory will be a precision Quantum Chromodynamics machine that will enable a vast physics program with electron+proton/ion collisions across a broad center-of-mass range. Measurements of hard probes such as heavy flavor in deep inelastic scatterings will be an essential component to the EIC physics program and are one of the detector R\&D driving aspects. In this paper we study the projected statistical precision of open charm hadron production through exclusive hadronic channel reconstruction with a silicon detector concept currently being developed using a PYTHIA-based simulation. We further study the impact of possible intrinsic charm in the proton on projected data, and estimate the constraint on the nuclear gluon parton distribution function (PDF) from the charm structure functions $F_{2}^{c\overline{c}}$ in $e$+Au collisions using a Bayesian PDF re-weighting technique. Our studies show the EIC will be capable delivering an unprecedented measurement of charm hadron production across a broad kinematic region and will provide strong constraints to both intrinsic charm and nuclear gluon PDFs.
hep-ph/9703332
Manuel Drees
Manuel Drees (APCTP, Seoul, Korea)
Are the H1 and ZEUS "High Q^2 Anomalies" Compatible with Each Other?
5 pages, 1 figure; LaTeX with equation.sty and epsf.sty. Replaced to fix typo in eq.(8c)
Phys.Lett. B403 (1997) 353-356
10.1016/S0370-2693(97)00525-X
APCTP 97-03
hep-ph
null
Both ZEUS and H1 have recently reported an excess of events at high $Q^2$ and high Bjorken--$x$. However, the $x$ distributions differ considerably; moreover, H1 sees more events with lower luminosity. Taken separately, the $x$ distributions and the number of observed events are consistent between the two experiments at the few percent level. However, when combined it becomes clear that the results of H1 and ZEUS are as (in)compatible with each other as each is with the Standard Model.
[ { "created": "Sat, 15 Mar 1997 05:49:30 GMT", "version": "v1" }, { "created": "Tue, 18 Mar 1997 02:33:25 GMT", "version": "v2" } ]
2009-10-30
[ [ "Drees", "Manuel", "", "APCTP, Seoul, Korea" ] ]
Both ZEUS and H1 have recently reported an excess of events at high $Q^2$ and high Bjorken--$x$. However, the $x$ distributions differ considerably; moreover, H1 sees more events with lower luminosity. Taken separately, the $x$ distributions and the number of observed events are consistent between the two experiments at the few percent level. However, when combined it becomes clear that the results of H1 and ZEUS are as (in)compatible with each other as each is with the Standard Model.
1405.3701
Andreas Crivellin
Andreas Crivellin
Overview of flavour physics with focus on the MSSM and 2HDMs
4 pages, 2 figures, contributions to the proceedings of "XLIXth Rencontres de Moriond, QCD and High Energy Interactions" ". arXiv admin note: substantial text overlap with arXiv:1405.2838
null
null
CERN-PH-TH-2014-090
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In these proceedings we give a concise review of some selected flavour-violation processes and their implications for two-Higgs-doublet models (2HDMs) and the MSSM. The processes under investigation are $\Delta F=2$ processes, $B_s\to\mu^+\mu^-$, $b\to s\gamma$, and tauonic $B$ decays. For each process we show the impact on the models.
[ { "created": "Wed, 14 May 2014 21:53:19 GMT", "version": "v1" }, { "created": "Wed, 4 Jun 2014 11:24:58 GMT", "version": "v2" } ]
2014-06-05
[ [ "Crivellin", "Andreas", "" ] ]
In these proceedings we give a concise review of some selected flavour-violation processes and their implications for two-Higgs-doublet models (2HDMs) and the MSSM. The processes under investigation are $\Delta F=2$ processes, $B_s\to\mu^+\mu^-$, $b\to s\gamma$, and tauonic $B$ decays. For each process we show the impact on the models.
0707.0253
Nikolai Zotov
S.P. Baranov (Lebedev Institute of Physics), N.P. Zotov (SINP, Moscow State University)
Upsilonium polarization as a touchstone in understanding the proton dynamics in QCD
8 pages, 2 figures
JETP Lett.86:435-438,2007
10.1134/S0021364007190010
null
hep-ph
null
In the framework of the k_t-factorization approach, the production of $\Upsilon mesons at the Fermilab Tevatron and CERN LHC is considered, and the predictions on the spin alignment parameter $\alpha$ are presented. We argue that measuring the polarization of quarkonium states can serve as a crucial test discriminating two competing theoretical approaches to parton dynamics in QCD.
[ { "created": "Mon, 2 Jul 2007 15:22:15 GMT", "version": "v1" }, { "created": "Tue, 10 Jul 2007 13:02:39 GMT", "version": "v2" } ]
2009-02-18
[ [ "Baranov", "S. P.", "", "Lebedev Institute of Physics" ], [ "Zotov", "N. P.", "", "SINP, Moscow\n State University" ] ]
In the framework of the k_t-factorization approach, the production of $\Upsilon mesons at the Fermilab Tevatron and CERN LHC is considered, and the predictions on the spin alignment parameter $\alpha$ are presented. We argue that measuring the polarization of quarkonium states can serve as a crucial test discriminating two competing theoretical approaches to parton dynamics in QCD.
1601.01658
P. S. Bhupal Dev
P. S. Bhupal Dev, Alejandro Ibarra
Heavy Neutrinos at Future Colliders
8 pages, 1 figure; prepared for the proceedings of the LFC15 Workshop, Trento, Italy (September 7-11, 2015)
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the current status and future prospects of heavy neutrino searches at the energy frontier, which might play an important role in vindicating the simplest seesaw paradigm as the new physics responsible for neutrino mass generation. After summarizing the current search limits and potential improvements at hadron colliders, we highlight the unparalleled sensitivities achievable in the clean environment of future lepton colliders.
[ { "created": "Thu, 7 Jan 2016 20:24:23 GMT", "version": "v1" } ]
2016-01-08
[ [ "Dev", "P. S. Bhupal", "" ], [ "Ibarra", "Alejandro", "" ] ]
We discuss the current status and future prospects of heavy neutrino searches at the energy frontier, which might play an important role in vindicating the simplest seesaw paradigm as the new physics responsible for neutrino mass generation. After summarizing the current search limits and potential improvements at hadron colliders, we highlight the unparalleled sensitivities achievable in the clean environment of future lepton colliders.
1801.06927
Chien-Thang Tran
Chien-Thang Tran, Mikhail A. Ivanov, J\"urgen G. K\"orner, Pietro Santorelli
Implications of new physics in the decays $B_c \to (J/\psi,\eta_c)\tau\nu$
23 pages, 10 figures, 3 tables, References updated, a version to appear in Phys. Rev. D
Phys. Rev. D 97, 054014 (2018)
10.1103/PhysRevD.97.054014
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the semileptonic decays of the $B_c$ meson into final charmonium states within the standard model and beyond. The relevant hadronic transition form factors are calculated in the framework of the covariant confined quark model developed by us. We focus on the tau mode of these decays, which may provide some hints of new physics effects. We extend the standard model by assuming a general effective Hamiltonian describing the $b\to c\tau\nu$ transition, which consists of the full set of the four-fermion operators. We then obtain experimental constraints on the Wilson coefficients corresponding to each operator and provide predictions for the branching fractions and other polarization observables in different new physics scenarios.
[ { "created": "Mon, 22 Jan 2018 01:16:04 GMT", "version": "v1" }, { "created": "Wed, 7 Mar 2018 13:55:46 GMT", "version": "v2" } ]
2018-03-21
[ [ "Tran", "Chien-Thang", "" ], [ "Ivanov", "Mikhail A.", "" ], [ "Körner", "Jürgen G.", "" ], [ "Santorelli", "Pietro", "" ] ]
We study the semileptonic decays of the $B_c$ meson into final charmonium states within the standard model and beyond. The relevant hadronic transition form factors are calculated in the framework of the covariant confined quark model developed by us. We focus on the tau mode of these decays, which may provide some hints of new physics effects. We extend the standard model by assuming a general effective Hamiltonian describing the $b\to c\tau\nu$ transition, which consists of the full set of the four-fermion operators. We then obtain experimental constraints on the Wilson coefficients corresponding to each operator and provide predictions for the branching fractions and other polarization observables in different new physics scenarios.
1607.03829
Michael E. Peskin
Keisuke Fujii, Christophe Grojean, Michael E. Peskin, Tim Barklow, Yuanning Gao, Shinya Kanemura, Hyungdo Kim, Jenny List, Mihoko Nojiri, Maxim Perelstein, Roman Poeschl, Juergen Reuter, Frank Simon, Tomohiko Tanabe, Jaehoon Yu, James D. Wells, Adam Falkowski, Shigeki Matsumoto, Takeo Moroi, Francois Richard, Junping Tian, Marcel Vos, Hiroshi Yokoya, Hitoshi Murayama, Hitoshi Yamamoto (LCC Physics Working Group)
Implications of the 750 GeV gamma-gamma Resonance as a Case Study for the International Linear Collider
39 pages, 5 figures, 5 tables; v2: some references added
null
null
ILC-NOTE-2016-067; DESY 16--145, IPMU16-0108, KEK Preprint 2016--9, LAL 16--185, MPP--2016--174, SLAC--PUB--16751
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If the gamma-gamma resonance at 750 GeV suggested by 2015 LHC data turns out to be a real effect, what are the implications for the physics case and upgrade path of the International Linear Collider? Whether or not the resonance is confirmed, this question provides an interesting case study testing the robustness of the ILC physics case. In this note, we address this question with two points: (1) Almost all models proposed for the new 750 GeV particle require additional new particles with electroweak couplings. The key elements of the 500 GeV ILC physics program---precision measurements of the Higgs boson, the top quark, and 4-fermion interactions---will powerfully discriminate among these models. This information will be important in conjunction with new LHC data, or alone, if the new particles accompanying the 750 GeV resonance are beyond the mass reach of the LHC. (2) Over a longer term, the energy upgrade of the ILC to 1 TeV already discussed in the ILC TDR will enable experiments in gamma-gamma and e+e- collisions to directly produce and study the 750 GeV particle from these unique initial states.
[ { "created": "Wed, 13 Jul 2016 17:17:36 GMT", "version": "v1" }, { "created": "Sun, 31 Jul 2016 23:49:17 GMT", "version": "v2" } ]
2016-08-02
[ [ "Fujii", "Keisuke", "", "LCC Physics Working Group" ], [ "Grojean", "Christophe", "", "LCC Physics Working Group" ], [ "Peskin", "Michael E.", "", "LCC Physics Working Group" ], [ "Barklow", "Tim", "", "LCC Physics Working Group" ], [...
If the gamma-gamma resonance at 750 GeV suggested by 2015 LHC data turns out to be a real effect, what are the implications for the physics case and upgrade path of the International Linear Collider? Whether or not the resonance is confirmed, this question provides an interesting case study testing the robustness of the ILC physics case. In this note, we address this question with two points: (1) Almost all models proposed for the new 750 GeV particle require additional new particles with electroweak couplings. The key elements of the 500 GeV ILC physics program---precision measurements of the Higgs boson, the top quark, and 4-fermion interactions---will powerfully discriminate among these models. This information will be important in conjunction with new LHC data, or alone, if the new particles accompanying the 750 GeV resonance are beyond the mass reach of the LHC. (2) Over a longer term, the energy upgrade of the ILC to 1 TeV already discussed in the ILC TDR will enable experiments in gamma-gamma and e+e- collisions to directly produce and study the 750 GeV particle from these unique initial states.
1409.1588
Jeremy Bernon
Jeremy Bernon, Beranger Dumont, Sabine Kraml
Status of Higgs couplings after Run-1 of the LHC using Lilith 1.0
12 pages, 4 figures
Phys. Rev. D 90, 071301 (2014)
10.1103/PhysRevD.90.071301
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We provide an update of the global fits of the couplings of the 125.5 GeV Higgs boson using all publicly available experimental results from Run-1 of the LHC as per Summer 2014. The fits are done by means of the new public code Lilith 1.0. We present a selection of results given in terms of signal strengths, reduced couplings, and for the Two-Higgs-Doublet Models of Type I and II.
[ { "created": "Thu, 4 Sep 2014 20:02:38 GMT", "version": "v1" } ]
2014-10-22
[ [ "Bernon", "Jeremy", "" ], [ "Dumont", "Beranger", "" ], [ "Kraml", "Sabine", "" ] ]
We provide an update of the global fits of the couplings of the 125.5 GeV Higgs boson using all publicly available experimental results from Run-1 of the LHC as per Summer 2014. The fits are done by means of the new public code Lilith 1.0. We present a selection of results given in terms of signal strengths, reduced couplings, and for the Two-Higgs-Doublet Models of Type I and II.
hep-ph/9412242
Chi-Keung Chow
Chi-Keung Chow
From Tetraquark to Hexaquark: A Systematic Study of Heavy Exotics in the Large $N_c$ Limit
14 pages in REVTeX, no Figures
Phys.Rev.D51:6327-6331,1995
10.1103/PhysRevD.51.6327
CALT-68-1964
hep-ph
null
A systematic study of multiquark exotics with one or $N_c-1$ heavy quarks in the large $N_c$ limit is presented. By binding a chiral soliton to a heavy meson, either a normal $N_c$-quark baryon or an exotic $(N_c+2)$-quark baryon is obtained. By replacing the heavy quark with $N_c-1$ heavy antiquarks, exotic $(2N_c-2)$-quark and $2N_c$-quark mesons are obtained. When $N_c = 3$, they are just the normal triquark baryon $Qqq$, the exotic pentaquark baryon $Q\bar q\bar q\bar q\bar q$, tetraquark di-meson $\bar Q \bar Q qq$ and the hexaquark di-baryon $\bar Q \bar Q \bar q \bar q\ bar q \bar q$ respectively. Their stabilities and decays are also discussed. In particular, it is shown that the ``heavy to heavy'' semileptonic decays are described by the Isgur--Wise form factors of the normal baryons.
[ { "created": "Mon, 5 Dec 1994 23:17:13 GMT", "version": "v1" } ]
2010-11-01
[ [ "Chow", "Chi-Keung", "" ] ]
A systematic study of multiquark exotics with one or $N_c-1$ heavy quarks in the large $N_c$ limit is presented. By binding a chiral soliton to a heavy meson, either a normal $N_c$-quark baryon or an exotic $(N_c+2)$-quark baryon is obtained. By replacing the heavy quark with $N_c-1$ heavy antiquarks, exotic $(2N_c-2)$-quark and $2N_c$-quark mesons are obtained. When $N_c = 3$, they are just the normal triquark baryon $Qqq$, the exotic pentaquark baryon $Q\bar q\bar q\bar q\bar q$, tetraquark di-meson $\bar Q \bar Q qq$ and the hexaquark di-baryon $\bar Q \bar Q \bar q \bar q\ bar q \bar q$ respectively. Their stabilities and decays are also discussed. In particular, it is shown that the ``heavy to heavy'' semileptonic decays are described by the Isgur--Wise form factors of the normal baryons.
2203.15710
Emanuele Angelo Bagnaschi
E. Bagnaschi, M. Chakraborti, S. Heinemeyer, I. Saha, G. Weiglein
Interdependence of the new "MUON G-2" Result and the $W$-Boson Mass
26 pages, 7 figures; v2: slight modification to text and note added in relation to the recent CDF MW measurement
null
10.1140/epjc/s10052-022-10402-0
CERN-TH-2022-034, DESY-22-041, IFT-UAM/CSIC-22-029
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The electroweak (EW) sector of the Minimal Supersymmetric extension of the Standard Model (MSSM), assuming the lightest neutralino as Dark Matter (DM) candidate, can account for a variety of experimental results. In particular it can account for the discrepancy between the experimental result for the anomalous magnetic moment of the muon, $(g-2)_{\mu}$, and its Standard Model (SM) prediction. The new "MUON G-2" result, combined with the older BNL result on $(g-2)_{\mu}$, yields a deviation from the SM prediction of $\Delta a_{\mu} = (25.1 \pm 5.9) \times 10^{-10}$, corresponding to $4.2~\sigma$. Using this updated bound, together with the other constraints, we calculate the MSSM prediction for the mass of the $W$ boson, $M_W$. We assume contributions only from the EW sector, with the colored sector of the MSSM taken to be heavy. We investigate five scenarios, distinguished by the mechanisms which yield a relic DM density in agreement with the latest Planck bounds. We find that with the new $(g-2)_{\mu}$ result taken into account and depending on the scenario, values up to $M_W^{\mathrm{MSSM}} \lesssim 80.376~\mathrm{GeV}$ are reached. The largest values are obtained for wino DM and in the case of slepton co-annihilation, where points well within the $1\,\sigma$ range of the experimental world average of $M_W^{\mathrm{exp}} = 80.379 \pm~0.012~\mathrm{GeV}$ are reached, whereas the SM predicts a too small value of $M_W^{\mathrm{SM}} = 80.353~\mathrm{GeV}$. We analyze the dependence of $M_W^{\mathrm{MSSM}}$ on the relevant masses of the EW superpartners and demonstrate that future $M_W$ measurements, e.g. at the ILC, could distinguish between various MSSM realizations. Sizable contributions to $M_W^{\mathrm{MSSM}}$ are associated with a relatively light $\tilde{\chi}^0_1$, accompanied by either a light chargino or a light smuon, setting interesting targets for future collider searches.
[ { "created": "Tue, 29 Mar 2022 16:13:28 GMT", "version": "v1" }, { "created": "Mon, 18 Apr 2022 16:11:36 GMT", "version": "v2" } ]
2022-06-08
[ [ "Bagnaschi", "E.", "" ], [ "Chakraborti", "M.", "" ], [ "Heinemeyer", "S.", "" ], [ "Saha", "I.", "" ], [ "Weiglein", "G.", "" ] ]
The electroweak (EW) sector of the Minimal Supersymmetric extension of the Standard Model (MSSM), assuming the lightest neutralino as Dark Matter (DM) candidate, can account for a variety of experimental results. In particular it can account for the discrepancy between the experimental result for the anomalous magnetic moment of the muon, $(g-2)_{\mu}$, and its Standard Model (SM) prediction. The new "MUON G-2" result, combined with the older BNL result on $(g-2)_{\mu}$, yields a deviation from the SM prediction of $\Delta a_{\mu} = (25.1 \pm 5.9) \times 10^{-10}$, corresponding to $4.2~\sigma$. Using this updated bound, together with the other constraints, we calculate the MSSM prediction for the mass of the $W$ boson, $M_W$. We assume contributions only from the EW sector, with the colored sector of the MSSM taken to be heavy. We investigate five scenarios, distinguished by the mechanisms which yield a relic DM density in agreement with the latest Planck bounds. We find that with the new $(g-2)_{\mu}$ result taken into account and depending on the scenario, values up to $M_W^{\mathrm{MSSM}} \lesssim 80.376~\mathrm{GeV}$ are reached. The largest values are obtained for wino DM and in the case of slepton co-annihilation, where points well within the $1\,\sigma$ range of the experimental world average of $M_W^{\mathrm{exp}} = 80.379 \pm~0.012~\mathrm{GeV}$ are reached, whereas the SM predicts a too small value of $M_W^{\mathrm{SM}} = 80.353~\mathrm{GeV}$. We analyze the dependence of $M_W^{\mathrm{MSSM}}$ on the relevant masses of the EW superpartners and demonstrate that future $M_W$ measurements, e.g. at the ILC, could distinguish between various MSSM realizations. Sizable contributions to $M_W^{\mathrm{MSSM}}$ are associated with a relatively light $\tilde{\chi}^0_1$, accompanied by either a light chargino or a light smuon, setting interesting targets for future collider searches.
1002.1971
John F. Gunion
Radovan Dermisek (U. Indiana) and John F. Gunion (U.C. Davis and CERN)
New constraints on a light CP-odd Higgs boson and related NMSSM Ideal Higgs Scenarios
24 pages, 25 figures, paper updated to incorporate final ALEPH limits in Z+4\tau channel.
Phys.Rev.D81:075003,2010
10.1103/PhysRevD.81.075003
CERN-PH-TH/2010-031
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent BaBar limits on $\br(\Upsilon(3S)\to \gam a\to \gam \tau^+\tau^-)$ and $\br(\Upsilon(3S)\to \gam a\to \gam \mu^+\mu^-)$ provide increased constraints on the $a b\anti b$ coupling of a CP-odd Higgs boson, $a$, with $m_a<M_{\Upsilon(3S)}$. We extract these limits from the BaBar data and compare to the limits previously obtained using other data sets, especially the CLEO-III $\br(\Upsilon(1S)\to \gam\to\tau^+\tau^-)$ limits. Comparisons are made to predictions in the context of "ideal"-Higgs NMSSM scenarios, in which the lightest CP-even Higgs boson, $h_1$, can have mass below $105\gev$ (as preferred by precision electroweak data) and yet can escape old LEP limits by virtue of decays to a pair of the lightest CP-odd Higgs bosons, $h_1\to a_1a_1$, with $m_{a_1}<2m_B$. Most such scenarios with $m_{a_1}<2m_\tau$ are eliminated, but the bulk of the $m_{a_1}>7.5\gev$ scenarios, which are theoretically the most favored, survive. We also outline the impact of the new ALEPH LEP results in the $\epem\to Z+4\tau$ channel. For $\tan\beta\geq 3$, only NMSSM ideal Higgs scenarios with $m_{h_1}\gsim 98\gev$ and $m_{a_1}$ close to $2m_B $ satisfy the ALEPH limits. For $\tan\beta\lsim 2$, the ALEPH limits are easily satisfied for the most theoretically preferred NMSSM scenarios, which are those with $m_{a_1}$ close to $2m_B$ and $m_{h_1}\sim 90\gev-100\gev$.
[ { "created": "Tue, 9 Feb 2010 21:06:34 GMT", "version": "v1" }, { "created": "Tue, 9 Mar 2010 23:10:33 GMT", "version": "v2" } ]
2010-04-14
[ [ "Dermisek", "Radovan", "", "U. Indiana" ], [ "Gunion", "John F.", "", "U.C. Davis and CERN" ] ]
Recent BaBar limits on $\br(\Upsilon(3S)\to \gam a\to \gam \tau^+\tau^-)$ and $\br(\Upsilon(3S)\to \gam a\to \gam \mu^+\mu^-)$ provide increased constraints on the $a b\anti b$ coupling of a CP-odd Higgs boson, $a$, with $m_a<M_{\Upsilon(3S)}$. We extract these limits from the BaBar data and compare to the limits previously obtained using other data sets, especially the CLEO-III $\br(\Upsilon(1S)\to \gam\to\tau^+\tau^-)$ limits. Comparisons are made to predictions in the context of "ideal"-Higgs NMSSM scenarios, in which the lightest CP-even Higgs boson, $h_1$, can have mass below $105\gev$ (as preferred by precision electroweak data) and yet can escape old LEP limits by virtue of decays to a pair of the lightest CP-odd Higgs bosons, $h_1\to a_1a_1$, with $m_{a_1}<2m_B$. Most such scenarios with $m_{a_1}<2m_\tau$ are eliminated, but the bulk of the $m_{a_1}>7.5\gev$ scenarios, which are theoretically the most favored, survive. We also outline the impact of the new ALEPH LEP results in the $\epem\to Z+4\tau$ channel. For $\tan\beta\geq 3$, only NMSSM ideal Higgs scenarios with $m_{h_1}\gsim 98\gev$ and $m_{a_1}$ close to $2m_B $ satisfy the ALEPH limits. For $\tan\beta\lsim 2$, the ALEPH limits are easily satisfied for the most theoretically preferred NMSSM scenarios, which are those with $m_{a_1}$ close to $2m_B$ and $m_{h_1}\sim 90\gev-100\gev$.
0804.3601
Danny Marfatia
Vernon Barger, Danny Marfatia, Azar Mustafayev
Neutrino sector impacts SUSY dark matter
18 pages, 7 figures, 1 table. Version to appear in PLB
Phys.Lett.B665:242-251,2008
10.1016/j.physletb.2008.06.010
NSF-KITP-08-30
hep-ph astro-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the fact that neutrinos are massive, we study the effect of neutrino Yukawa couplings on neutralino dark matter observables within the framework of a supersymmetric seesaw. We find that neutrino couplings significantly affect the neutralino relic density in regions of parameter space where soft SUSY-breaking slepton masses and/or trilinear couplings are large. Depending on the size of the couplings, the neutralino relic density spans over an order of magnitude in the A-funnel, focus point and stop-coannihilation regions of mSUGRA. We also show that dark matter detection rates can be modified by up to several orders of magnitude.
[ { "created": "Wed, 23 Apr 2008 17:02:17 GMT", "version": "v1" }, { "created": "Tue, 3 Jun 2008 19:42:08 GMT", "version": "v2" } ]
2008-11-26
[ [ "Barger", "Vernon", "" ], [ "Marfatia", "Danny", "" ], [ "Mustafayev", "Azar", "" ] ]
Motivated by the fact that neutrinos are massive, we study the effect of neutrino Yukawa couplings on neutralino dark matter observables within the framework of a supersymmetric seesaw. We find that neutrino couplings significantly affect the neutralino relic density in regions of parameter space where soft SUSY-breaking slepton masses and/or trilinear couplings are large. Depending on the size of the couplings, the neutralino relic density spans over an order of magnitude in the A-funnel, focus point and stop-coannihilation regions of mSUGRA. We also show that dark matter detection rates can be modified by up to several orders of magnitude.
1510.03731
Antoni Szczurek
Antoni Szczurek
Higgs production within $k_t$-factorization with unintegrated gluon distributions
6 pages, 5 figures, talk given by A. Szczurek at the European Physical Society Conference on High Energy Physics (EPS-HEP 2015), 22--29 July 2015, Vienna, Austria
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present differential cross sections for Higgs boson and/or two-photon production from intermediate (virtual) Higgs boson within the formalism of $k_t$-factorization. Resulting distributions for two photons from the Higgs boson are compared with recent ATLAS collaboration data. In contrast to a recent calculation the leading order $g g \to H$ contribution is rather small compared to the ATLAS experimental data ($\gamma \gamma$ transverse momentum and rapidity distributions). We include also higher-order contribution $g g \to H (\to \gamma \gamma) g$, $g g \to g H g$ and the contribution of the $W^+ W^-$ and $Z^0 Z^0$ exchanges. The $gg\to Hg$ mechanism gives a similar contribution as the $gg\to H$ mechanism. We argue that there is almost no double counting when adding $gg\to H$ and $gg\to Hg$ contributions due to different topology of corresponding Feynman diagrams. The final sum is comparable with the ATLAS two-photon data.
[ { "created": "Tue, 13 Oct 2015 15:10:34 GMT", "version": "v1" } ]
2015-10-14
[ [ "Szczurek", "Antoni", "" ] ]
We present differential cross sections for Higgs boson and/or two-photon production from intermediate (virtual) Higgs boson within the formalism of $k_t$-factorization. Resulting distributions for two photons from the Higgs boson are compared with recent ATLAS collaboration data. In contrast to a recent calculation the leading order $g g \to H$ contribution is rather small compared to the ATLAS experimental data ($\gamma \gamma$ transverse momentum and rapidity distributions). We include also higher-order contribution $g g \to H (\to \gamma \gamma) g$, $g g \to g H g$ and the contribution of the $W^+ W^-$ and $Z^0 Z^0$ exchanges. The $gg\to Hg$ mechanism gives a similar contribution as the $gg\to H$ mechanism. We argue that there is almost no double counting when adding $gg\to H$ and $gg\to Hg$ contributions due to different topology of corresponding Feynman diagrams. The final sum is comparable with the ATLAS two-photon data.
hep-ph/9702364
null
U. Baur (SUNY-Buffalo), T. Han (UC-Davis), N. Kauer (UW-Madison), R. Sobey (UC-Davis), and D. Zeppenfeld (UW-Madison)
$W\gamma\gamma$ Production at the Fermilab Tevatron Collider: Gauge Invariance and Radiation Amplitude Zero
37 pages,12 figures, postscript file also available via anonymous ftp at ftp://ucdhep.ucdavis.edu/han/vvv/Wgmgm.ps
Phys.Rev. D56 (1997) 140-150
10.1103/PhysRevD.56.140
UB-HET-97-01, UCD-97-02, MADPH-97-986
hep-ph
null
The electroweak process $p\bar p \to \ell^\pm\nu\gamma\gamma$ is calculated at tree level, including finite W width effects. In order to obtain a gauge invariant amplitude, the imaginary parts of $WW\gamma$ triangle graphs and $WW\gamma\gamma$ box diagrams have to be included, in addition to resumming the imaginary contributions to the W polarization. We demonstrate the existence of a radiation amplitude zero in $p\bar p \to W^\pm \gamma\gamma \to \ell^\pm\nu\gamma\gamma$, and discuss how it may be observed in correlations of the $\gamma\gamma$ and lepton rapidities at the Fermilab Tevatron.
[ { "created": "Tue, 18 Feb 1997 21:14:28 GMT", "version": "v1" } ]
2009-10-30
[ [ "Baur", "U.", "", "SUNY-Buffalo" ], [ "Han", "T.", "", "UC-Davis" ], [ "Kauer", "N.", "", "UW-Madison" ], [ "Sobey", "R.", "", "UC-Davis" ], [ "Zeppenfeld", "D.", "", "UW-Madison" ] ]
The electroweak process $p\bar p \to \ell^\pm\nu\gamma\gamma$ is calculated at tree level, including finite W width effects. In order to obtain a gauge invariant amplitude, the imaginary parts of $WW\gamma$ triangle graphs and $WW\gamma\gamma$ box diagrams have to be included, in addition to resumming the imaginary contributions to the W polarization. We demonstrate the existence of a radiation amplitude zero in $p\bar p \to W^\pm \gamma\gamma \to \ell^\pm\nu\gamma\gamma$, and discuss how it may be observed in correlations of the $\gamma\gamma$ and lepton rapidities at the Fermilab Tevatron.
1611.08166
Alexander M\"uck
Martin Beneke, Laura Jenniches, Alexander M\"uck, Maria Ubiali
Radiative distortion of kinematic edges in cascade decays
15 pages, 5 figures
null
10.1016/j.physletb.2017.04.018
TUM-HEP-1071/16, TTK-16-50, Cavendish-HEP-16/18
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Kinematic edges of cascade decays of new particles produced in high-energy collisions may provide important constraints on the involved particles' masses. For the exemplary case of gluino decay $\tilde{g}\to q\bar q \tilde{\chi}$ into a pair of quarks and a neutralino through a squark resonance, we study the hadronic invariant mass distribution in the vicinity of the kinematic edge. We perform a next-to-leading order calculation in the strong coupling $\alpha_s$ and the ratio of squark width and squark mass $\Gamma_\tilde{q}/m_\tilde{q}$, based on a systematic expansion in $\Gamma_\tilde{q}/m_\tilde{q}$. The separation into hard, collinear and soft contributions elucidates the process dependent and universal features of distributions in the edge region, represented by on-shell decay matrix elements, universal jet functions and a soft function that depends on the resonance propagator and soft Wilson lines.
[ { "created": "Thu, 24 Nov 2016 12:40:14 GMT", "version": "v1" } ]
2017-04-19
[ [ "Beneke", "Martin", "" ], [ "Jenniches", "Laura", "" ], [ "Mück", "Alexander", "" ], [ "Ubiali", "Maria", "" ] ]
Kinematic edges of cascade decays of new particles produced in high-energy collisions may provide important constraints on the involved particles' masses. For the exemplary case of gluino decay $\tilde{g}\to q\bar q \tilde{\chi}$ into a pair of quarks and a neutralino through a squark resonance, we study the hadronic invariant mass distribution in the vicinity of the kinematic edge. We perform a next-to-leading order calculation in the strong coupling $\alpha_s$ and the ratio of squark width and squark mass $\Gamma_\tilde{q}/m_\tilde{q}$, based on a systematic expansion in $\Gamma_\tilde{q}/m_\tilde{q}$. The separation into hard, collinear and soft contributions elucidates the process dependent and universal features of distributions in the edge region, represented by on-shell decay matrix elements, universal jet functions and a soft function that depends on the resonance propagator and soft Wilson lines.
hep-ph/0411290
Jerrold Franklin
Jerrold Franklin
How High is High x?
Presented at HIX 2004, Marseille July 23-26, 2004
null
10.1063/1.1871646
null
hep-ph nucl-th
null
A general three quark bound state satisfying the Pauli principle, and conserving angular momentum and isospin, is used to investigate the spin structure of nucleons at high $x$. It is shown that, if a spin up quark dominates as $x$$\to$1 for a spin up proton, it must be a u quark. Then both $A_{1p}$ and $A_{1n}$, as well as the quark spin distribution $\Delta u/u$, will approach 1 as $x$$\to$1. The spin distribution $\Delta d/d$ does not approach 1, but is bound by the limits $-{1/3}\le\Delta d/d\le 0$ for any $x$. The ratio {$F_{1n}/F_{1p}$ will approach 1/4} (not3/7).
[ { "created": "Mon, 22 Nov 2004 12:42:36 GMT", "version": "v1" } ]
2009-11-10
[ [ "Franklin", "Jerrold", "" ] ]
A general three quark bound state satisfying the Pauli principle, and conserving angular momentum and isospin, is used to investigate the spin structure of nucleons at high $x$. It is shown that, if a spin up quark dominates as $x$$\to$1 for a spin up proton, it must be a u quark. Then both $A_{1p}$ and $A_{1n}$, as well as the quark spin distribution $\Delta u/u$, will approach 1 as $x$$\to$1. The spin distribution $\Delta d/d$ does not approach 1, but is bound by the limits $-{1/3}\le\Delta d/d\le 0$ for any $x$. The ratio {$F_{1n}/F_{1p}$ will approach 1/4} (not3/7).
1912.08882
Sebastian Jaskiewicz
Sebastian Jaskiewicz
Next-to-leading power threshold factorization for Drell-Yan production
12 pages, contribution to the proceedings of the 14th International Symposium on Radiative Corrections (RADCOR2019), 9-13 September 2019, Avignon, France. Based on arXiv: 1912.01585
null
null
TUM-HEP-1246/19
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the next-to-leading power (NLP) factorization formula for the $q\bar{q}\to \gamma^*+X$ channel of the Drell-Yan production near the kinematic threshold limit. The formalism used for the computation of next-to-leading power corrections within soft-collinear effective field theory is introduced, we discuss the emergence of new objects, the NLP collinear functions, and define them through an operator matching equation. We review the leading power factorization before extending it to subleading powers. We also present the one-loop result for the newly introduced collinear function, and demonstrate explicitly conceptual issues in performing next-to-leading logarithmic resummation at next-to-leading power.
[ { "created": "Wed, 18 Dec 2019 20:47:39 GMT", "version": "v1" } ]
2019-12-20
[ [ "Jaskiewicz", "Sebastian", "" ] ]
We present the next-to-leading power (NLP) factorization formula for the $q\bar{q}\to \gamma^*+X$ channel of the Drell-Yan production near the kinematic threshold limit. The formalism used for the computation of next-to-leading power corrections within soft-collinear effective field theory is introduced, we discuss the emergence of new objects, the NLP collinear functions, and define them through an operator matching equation. We review the leading power factorization before extending it to subleading powers. We also present the one-loop result for the newly introduced collinear function, and demonstrate explicitly conceptual issues in performing next-to-leading logarithmic resummation at next-to-leading power.
1012.4094
Vasiliki Mitsou
Nick E. Mavromatos, Vasiliki A. Mitsou, Sarben Sarkar and Ariadne Vergou
Implications of a Stochastic Microscopic Finsler Cosmology
44 pages, 5 figures. Amended version including detailed discussion on effects of D-particle foam on Universe expansion, and on production of D-particles at colliders (LHC). No change in conclusions. Version to appear in EPJC
Eur. Phys. J. C72 (2012) 1956
10.1140/epjc/s10052-012-1956-7
CERN-PH-TH/2010-284; KCL-PH-TH/2010-27; IFIC/10-48
hep-ph astro-ph.CO gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Within the context of supersymmetric space-time (D-particle) foam in string/brane-theory, we discuss a Finsler-induced Cosmology and its implications for (thermal) Dark Matter abundances. This constitutes a truly microscopic model of dynamical space-time, where Finsler geometries arise naturally. The D-particle foam model involves point-like brane defects (D-particles), which provide the topologically non-trivial foamy structures of space-time. The D-particles can capture and emit stringy matter and this leads to a recoil of D-particles. It is indicated how one effect of such a recoil of D-particles is a back-reaction on the space-time metric of Finsler type which is stochastic. We show that such a type of stochastic space-time foam can lead to acceptable cosmologies at late epochs of the Universe, due to the non-trivial properties of the supersymmetric (BPS like) D-particle defects, which are such so as not to affect significantly the Hubble expansion. The restrictions placed on the free parameters of the Finsler type metric are obtained from solving the Boltzmann equation in this background for relic abundances of a Lightest Supersymmetric Particle (LSP) dark matter candidate. It is demonstrated that the D-foam acts as a source for particle production in the Boltzmann equation, thereby leading to enhanced thermal LSP relic abundances relative to those in the Standard LambdaCDM Cosmology. For D-particle masses of order TeV, such effects may be relevant for dark matter searches at colliders. The latter constraints complement those coming from high energy gamma-ray astronomy on the induced vacuum refractive index that D-foam models entail. We also comment briefly on the production mechanisms of such TeV-mass stringy defects at colliders, which, in view of the current LHC experimental searches, will impose further constraints on their couplings.
[ { "created": "Sat, 18 Dec 2010 14:53:06 GMT", "version": "v1" }, { "created": "Sun, 18 Mar 2012 09:20:18 GMT", "version": "v2" } ]
2012-04-03
[ [ "Mavromatos", "Nick E.", "" ], [ "Mitsou", "Vasiliki A.", "" ], [ "Sarkar", "Sarben", "" ], [ "Vergou", "Ariadne", "" ] ]
Within the context of supersymmetric space-time (D-particle) foam in string/brane-theory, we discuss a Finsler-induced Cosmology and its implications for (thermal) Dark Matter abundances. This constitutes a truly microscopic model of dynamical space-time, where Finsler geometries arise naturally. The D-particle foam model involves point-like brane defects (D-particles), which provide the topologically non-trivial foamy structures of space-time. The D-particles can capture and emit stringy matter and this leads to a recoil of D-particles. It is indicated how one effect of such a recoil of D-particles is a back-reaction on the space-time metric of Finsler type which is stochastic. We show that such a type of stochastic space-time foam can lead to acceptable cosmologies at late epochs of the Universe, due to the non-trivial properties of the supersymmetric (BPS like) D-particle defects, which are such so as not to affect significantly the Hubble expansion. The restrictions placed on the free parameters of the Finsler type metric are obtained from solving the Boltzmann equation in this background for relic abundances of a Lightest Supersymmetric Particle (LSP) dark matter candidate. It is demonstrated that the D-foam acts as a source for particle production in the Boltzmann equation, thereby leading to enhanced thermal LSP relic abundances relative to those in the Standard LambdaCDM Cosmology. For D-particle masses of order TeV, such effects may be relevant for dark matter searches at colliders. The latter constraints complement those coming from high energy gamma-ray astronomy on the induced vacuum refractive index that D-foam models entail. We also comment briefly on the production mechanisms of such TeV-mass stringy defects at colliders, which, in view of the current LHC experimental searches, will impose further constraints on their couplings.
hep-ph/9409216
Antonio Pineda
A. Pineda and J. Soto
Heavy Quark Hadronic Lagrangian for S-wave Quarkonium
38 pages, TeX, general rewritten version with minor changes in physical outcomes, to appear in Phys. Rev. D
Phys.Rev. D53 (1996) 3983-3997
10.1103/PhysRevD.53.3983
UB-ECM-PF-94/19
hep-ph
null
We use Heavy Quark Effective Theory (HQET) techniques to parametrize certain non-perturbative effects related to quantum fluctuations that put both heavy quark and antiquark in quarkonium almost on shell. The large off-shell momentum contributions are calculated using Coulomb type states. The almost on-shell momentum contributions are evaluated using an effective 'chiral' lagrangian which incorporates the relevant symmetries of the HQET for quarks and antiquarks. The cut-off dependence of both contributions matches perfectly. The decay constants and the matrix elements of bilinear currents at zero recoil are calculated. The new non-perturbative contributions from the on-shell region are parametrized by a single constant. They turn out to be $O(\alpha^2/\Lambda_{QCD} a_{n})$, $a_{n}$ being the Bohr radius and $\alpha$ the strong coupling constant, times the non-perturbative contribution coming from the multipole expansion (gluon condensate). We discuss the physical applications to $\Upsilon$, $J/\Psi$ and $B_{c}$ systems.
[ { "created": "Fri, 2 Sep 1994 20:39:45 GMT", "version": "v1" }, { "created": "Tue, 23 Jan 1996 19:11:47 GMT", "version": "v2" } ]
2016-09-01
[ [ "Pineda", "A.", "" ], [ "Soto", "J.", "" ] ]
We use Heavy Quark Effective Theory (HQET) techniques to parametrize certain non-perturbative effects related to quantum fluctuations that put both heavy quark and antiquark in quarkonium almost on shell. The large off-shell momentum contributions are calculated using Coulomb type states. The almost on-shell momentum contributions are evaluated using an effective 'chiral' lagrangian which incorporates the relevant symmetries of the HQET for quarks and antiquarks. The cut-off dependence of both contributions matches perfectly. The decay constants and the matrix elements of bilinear currents at zero recoil are calculated. The new non-perturbative contributions from the on-shell region are parametrized by a single constant. They turn out to be $O(\alpha^2/\Lambda_{QCD} a_{n})$, $a_{n}$ being the Bohr radius and $\alpha$ the strong coupling constant, times the non-perturbative contribution coming from the multipole expansion (gluon condensate). We discuss the physical applications to $\Upsilon$, $J/\Psi$ and $B_{c}$ systems.
0709.2611
Marco Ruggieri
Marco Ruggieri
Instabilities in two flavor quark matter
6 pages. Talk given at QCD@Work07, Martina Franca (Italy). Some typos corrected, one reference added
AIPConf.Proc.964:250-255,2007
10.1063/1.2823859
null
hep-ph
null
I discuss briefly the instabilities of two flavor quark matter, paying attention to the gradient instability which develops in the g2SC phase in the Goldstone $U(1)_A$ sector.
[ { "created": "Mon, 17 Sep 2007 13:02:38 GMT", "version": "v1" }, { "created": "Thu, 4 Oct 2007 10:58:37 GMT", "version": "v2" } ]
2008-11-26
[ [ "Ruggieri", "Marco", "" ] ]
I discuss briefly the instabilities of two flavor quark matter, paying attention to the gradient instability which develops in the g2SC phase in the Goldstone $U(1)_A$ sector.
hep-ph/9804246
Gao Yanming
Wang Xin and Li Jiarong
Effective Two-loop Thermodynamic Potential with Fermions in the real-time formalism of thermal field theory
11 pages,4 figures
Commun.Theor.Phys. 33 (2000) 253-262
null
HZPP-9806
hep-ph
null
Within the real-time formalism (RTF) of thermal field theory,we apply the hard thermal loop (HTL) resummation technique to calculating effective two-loop thermodynamic potential in quark-gluon plasma (QGP) and its renormalization. The result with collective effects is obtained, which is valid for an arbitrary number of quark flavors with masses.
[ { "created": "Tue, 7 Apr 1998 06:48:02 GMT", "version": "v1" } ]
2007-05-23
[ [ "Xin", "Wang", "" ], [ "Jiarong", "Li", "" ] ]
Within the real-time formalism (RTF) of thermal field theory,we apply the hard thermal loop (HTL) resummation technique to calculating effective two-loop thermodynamic potential in quark-gluon plasma (QGP) and its renormalization. The result with collective effects is obtained, which is valid for an arbitrary number of quark flavors with masses.
hep-ph/0504084
Chun-Khiang Chua
Chun-Khiang Chua, Wei-Shu Hou
Implications of Bbar to D0 h0 Decays on Bbar to D Kbar, Dbar Kbar Decays
24 pages, 4 figures
Phys.Rev. D72 (2005) 036002
10.1103/PhysRevD.72.036002
null
hep-ph
null
The recently observed color suppressed B0bar to D0 pi0, D0 eta, D0 eta', Ds+ K-and D0 K0bar decay modes all have rates larger than expected, hinting at the presence of final state interactions. We study rescattering effects in Bbar to D P, D Kbar and Dbar Kbar modes in the quasi-elastic approach, which is extended to accommodate D0 eta' without using U(3) symmetry. The D0bar Kbar modes are of interest in the determination of the unitarity angle phi3/gamma. The updated DP data are used to extract the effective Wilson coefficients a_1^{eff} ~ 0.92, a_2^{eff} ~ 0.22, three strong phases delta ~ 62 deg., theta ~ 24 deg., sigma ~ 127 deg., and the mixing angle tau~2 deg. The values of delta and theta are close to our previous results. The smallness of tau implies small mixing of D0 eta1 with other modes. Predictions for D0 K-, D+ K- and D0 K0bar agree with data. The framework applies to Bbar to Dbar Kbar decays, and rates for D0bar K-, D- K0, Ds- pi0, Ds- eta and Ds- eta' modes are predicted. From B- to D0bar K- and D0 K- rates, we find r_B=0.09\pm 0.02.
[ { "created": "Tue, 12 Apr 2005 08:46:30 GMT", "version": "v1" } ]
2009-11-11
[ [ "Chua", "Chun-Khiang", "" ], [ "Hou", "Wei-Shu", "" ] ]
The recently observed color suppressed B0bar to D0 pi0, D0 eta, D0 eta', Ds+ K-and D0 K0bar decay modes all have rates larger than expected, hinting at the presence of final state interactions. We study rescattering effects in Bbar to D P, D Kbar and Dbar Kbar modes in the quasi-elastic approach, which is extended to accommodate D0 eta' without using U(3) symmetry. The D0bar Kbar modes are of interest in the determination of the unitarity angle phi3/gamma. The updated DP data are used to extract the effective Wilson coefficients a_1^{eff} ~ 0.92, a_2^{eff} ~ 0.22, three strong phases delta ~ 62 deg., theta ~ 24 deg., sigma ~ 127 deg., and the mixing angle tau~2 deg. The values of delta and theta are close to our previous results. The smallness of tau implies small mixing of D0 eta1 with other modes. Predictions for D0 K-, D+ K- and D0 K0bar agree with data. The framework applies to Bbar to Dbar Kbar decays, and rates for D0bar K-, D- K0, Ds- pi0, Ds- eta and Ds- eta' modes are predicted. From B- to D0bar K- and D0 K- rates, we find r_B=0.09\pm 0.02.
hep-ph/9802297
Wu Ning
Ning Wu
Some discussions on strong interaction
5 pages, no figure, LaTex file
null
null
null
hep-ph
null
Using the gauge field model with massive gauge bosons, we could construct a new model to describe the strong interaction. In this new quantum chromodynamics(QCD) model, we will introduce two sets of gluon fields, one set is massive and another set is massless. Correspondingly, there may exists three sets of glueballs which have the same spin-parity but have different masses. A possible new kind of long-range force field is also discussed in this paper.
[ { "created": "Wed, 11 Feb 1998 03:13:29 GMT", "version": "v1" } ]
2007-05-23
[ [ "Wu", "Ning", "" ] ]
Using the gauge field model with massive gauge bosons, we could construct a new model to describe the strong interaction. In this new quantum chromodynamics(QCD) model, we will introduce two sets of gluon fields, one set is massive and another set is massless. Correspondingly, there may exists three sets of glueballs which have the same spin-parity but have different masses. A possible new kind of long-range force field is also discussed in this paper.
1509.03993
Hannu Paukkunen
Fran\c{c}ois Arleo, \'Emilien Chapon, Hannu Paukkunen
Scaling properties of inclusive W$^\pm$ production at hadron colliders
The version to appear in EPJC, references updated in v3
null
10.1140/epjc/s10052-016-4049-1
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the hadroproduction of W gauge bosons in their leptonic decay mode. Starting from the leading-order expressions, we show that by defining a suitable scaling variable the centre-of-mass dependence of the cross sections at the LHC energies can be essentially described by a simple power law. The scaling exponent is directly linked to the small-$x$ behaviour of parton distribution functions (PDF) which, at the high virtualities involved in W production, is largely dictated by QCD evolution equations. This entails a particularly simple scaling law for the lepton charge asymmetry and also predicts that measurements in different collision systems (p-p, p-$\bar{\rm p}$, p-Pb Pb-Pb) are straightforwardly related. The expectations are compared with the existing data and a very good overall agreement is observed. It is shown that the PDF uncertainty in certain cross-section ratios between nearby centre-of-mass energies can be significantly reduced by taking the ratios at fixed value of scaling variable instead of fixed rapidity.
[ { "created": "Mon, 14 Sep 2015 08:38:46 GMT", "version": "v1" }, { "created": "Thu, 31 Mar 2016 11:53:09 GMT", "version": "v2" }, { "created": "Fri, 15 Apr 2016 05:36:32 GMT", "version": "v3" } ]
2016-05-04
[ [ "Arleo", "François", "" ], [ "Chapon", "Émilien", "" ], [ "Paukkunen", "Hannu", "" ] ]
We consider the hadroproduction of W gauge bosons in their leptonic decay mode. Starting from the leading-order expressions, we show that by defining a suitable scaling variable the centre-of-mass dependence of the cross sections at the LHC energies can be essentially described by a simple power law. The scaling exponent is directly linked to the small-$x$ behaviour of parton distribution functions (PDF) which, at the high virtualities involved in W production, is largely dictated by QCD evolution equations. This entails a particularly simple scaling law for the lepton charge asymmetry and also predicts that measurements in different collision systems (p-p, p-$\bar{\rm p}$, p-Pb Pb-Pb) are straightforwardly related. The expectations are compared with the existing data and a very good overall agreement is observed. It is shown that the PDF uncertainty in certain cross-section ratios between nearby centre-of-mass energies can be significantly reduced by taking the ratios at fixed value of scaling variable instead of fixed rapidity.
hep-ph/0304129
Antoni Szczurek
Antoni Szczurek
From unintegrated gluon distributions to particle production in nucleon-nucleon collisions at RHIC energies
27 pages, 14 figures To appear in the special issue of Acta Physica Polonica to celebrate the 65th Birthday of Prof. Jan Kwiecinski
Acta Phys.Polon. B34 (2003) 3191-3214
null
null
hep-ph
null
The inclusive distributions of gluons and pions are calculated with absolute normalization for high-energy nucleon-nucleon collisions. The results for several unintegrated gluon distributions from the literature are compared. The gluon distribution proposed recently by Kharzeev and Levin based on the idea of gluon saturation is tested against DIS data from HERA. We find huge differences in both rapidity and transverse momentum distributions of gluons and pions in nucleon-nucleon collisions for different models of unintegrated gluon distributions. The approximations used recently in the literature are discussed. The Karzeev-Levin gluon distribution gives extremely good description of momentum distribution of charged hadrons at midrapidities. Contrary to a recent claim in the literature, we find that the gluonic mechanism discussed does not describe the inclusive spectra of charged particles in the fragmentation region, i.e. in the region of large $|y|$ for any unintegrated gluon distribution from the literature.
[ { "created": "Mon, 14 Apr 2003 15:05:14 GMT", "version": "v1" } ]
2007-05-23
[ [ "Szczurek", "Antoni", "" ] ]
The inclusive distributions of gluons and pions are calculated with absolute normalization for high-energy nucleon-nucleon collisions. The results for several unintegrated gluon distributions from the literature are compared. The gluon distribution proposed recently by Kharzeev and Levin based on the idea of gluon saturation is tested against DIS data from HERA. We find huge differences in both rapidity and transverse momentum distributions of gluons and pions in nucleon-nucleon collisions for different models of unintegrated gluon distributions. The approximations used recently in the literature are discussed. The Karzeev-Levin gluon distribution gives extremely good description of momentum distribution of charged hadrons at midrapidities. Contrary to a recent claim in the literature, we find that the gluonic mechanism discussed does not describe the inclusive spectra of charged particles in the fragmentation region, i.e. in the region of large $|y|$ for any unintegrated gluon distribution from the literature.
1906.06486
Sibo Zheng
Shuai Xu and Sibo Zheng
R-Symmetric NMSSM
v4: 15 pages, 3 figures
null
10.1088/1674-1137/aca95c
null
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
It is well known that the observed Higgs mass is more naturally explained in the NMSSM than in the MSSM. Without any violation of this success, there are variants on the NMSSM which can lead to new phenomenologies. In this study we propose a new variant of NMSSM by imposing an unbroken $R$ symmetry. We firstly identify the minimal structure of such scenario from the perspective of both simplicity and viability, then compare model predictions to current experimental limits, and finally highlight main features that differ from the well-known scenarios.
[ { "created": "Sat, 15 Jun 2019 07:22:47 GMT", "version": "v1" }, { "created": "Thu, 20 Jun 2019 00:42:46 GMT", "version": "v2" }, { "created": "Tue, 3 Dec 2019 14:30:18 GMT", "version": "v3" }, { "created": "Tue, 9 Feb 2021 10:39:54 GMT", "version": "v4" }, { "cre...
2023-07-25
[ [ "Xu", "Shuai", "" ], [ "Zheng", "Sibo", "" ] ]
It is well known that the observed Higgs mass is more naturally explained in the NMSSM than in the MSSM. Without any violation of this success, there are variants on the NMSSM which can lead to new phenomenologies. In this study we propose a new variant of NMSSM by imposing an unbroken $R$ symmetry. We firstly identify the minimal structure of such scenario from the perspective of both simplicity and viability, then compare model predictions to current experimental limits, and finally highlight main features that differ from the well-known scenarios.
0705.4421
Robert Fleischer
Robert Fleischer (CERN)
Exploring CP Violation and Penguin Effects through $B^0_d \to D^+ D^-$ and $B^0_s \to D^+_s D^-_s$
18 pages, 6 figures
Eur.Phys.J.C51:849-858,2007
10.1140/epjc/s10052-007-0341-4
CERN-PH-TH/2007-092
hep-ph
null
The decay $B^0_d \to D^+ D^-$ offers an interesting probe of CP violation, but requires control of penguin effects, which can be done through $B^0_s \to D^+_s D^-_s$ by means of the $U$-spin flavour symmetry of strong interactions. Recently, the Belle collaboration reported indications of large CP violation in the $B^0_d$ decay, which were, however, not confirmed by BaBar, and first signals of the $B^0_s$ channel were observed at the Tevatron. In view of these developments and the quickly approaching start of the LHC, we explore the allowed region in observable space for CP violation in $B^0_d \to D^+ D^-$, perform theoretical estimates of the relevant hadronic penguin parameters and observables, and address questions both about the most promising strategies for the extraction of CP-violating phases and about the interplay with other measurements of CP violation and the search for new physics. As far as the latter aspect is concerned, we point out that the $B^0_{q} \to D_{q}^+ D^-_{q}$ system provides a setting for the determination of the $B^0_q$-$\bar B^0_q$ mixing phases ($q\in\{d,s\}$) that is complementary to the conventional $B^0_d\to J/\psi K_S$ and $B^0_s\to J/\psi \phi$ modes with respect to possible new-physics effects in the electroweak penguin sector.
[ { "created": "Wed, 30 May 2007 16:12:51 GMT", "version": "v1" } ]
2008-11-26
[ [ "Fleischer", "Robert", "", "CERN" ] ]
The decay $B^0_d \to D^+ D^-$ offers an interesting probe of CP violation, but requires control of penguin effects, which can be done through $B^0_s \to D^+_s D^-_s$ by means of the $U$-spin flavour symmetry of strong interactions. Recently, the Belle collaboration reported indications of large CP violation in the $B^0_d$ decay, which were, however, not confirmed by BaBar, and first signals of the $B^0_s$ channel were observed at the Tevatron. In view of these developments and the quickly approaching start of the LHC, we explore the allowed region in observable space for CP violation in $B^0_d \to D^+ D^-$, perform theoretical estimates of the relevant hadronic penguin parameters and observables, and address questions both about the most promising strategies for the extraction of CP-violating phases and about the interplay with other measurements of CP violation and the search for new physics. As far as the latter aspect is concerned, we point out that the $B^0_{q} \to D_{q}^+ D^-_{q}$ system provides a setting for the determination of the $B^0_q$-$\bar B^0_q$ mixing phases ($q\in\{d,s\}$) that is complementary to the conventional $B^0_d\to J/\psi K_S$ and $B^0_s\to J/\psi \phi$ modes with respect to possible new-physics effects in the electroweak penguin sector.
hep-ph/0003164
Sidney Bludman
Sidney A. Bludman
Vacuum Energy: "If Not Now, Then When?"
revision, extension of astro-ph/0002204, with one extra figure
null
10.1016/S0375-9474(99)00733-2
DESY 00/042
hep-ph
null
For a flat universe presently dominated by static or dynamic vacuum energy, cosmological constant (LCDM) or quintessence (QCDM), we calculate the asymptotic collapsed mass fraction as function of the present ratio of smooth energy to matter energy $\rat=(1-\omm)/\omm$. Identifying these collapsed fractions as anthropic probabilities, we find the observed present ratio $\rat \sim 2$ to be likely in LCDM, but most likely in QCDM.
[ { "created": "Thu, 16 Mar 2000 13:57:28 GMT", "version": "v1" } ]
2009-10-31
[ [ "Bludman", "Sidney A.", "" ] ]
For a flat universe presently dominated by static or dynamic vacuum energy, cosmological constant (LCDM) or quintessence (QCDM), we calculate the asymptotic collapsed mass fraction as function of the present ratio of smooth energy to matter energy $\rat=(1-\omm)/\omm$. Identifying these collapsed fractions as anthropic probabilities, we find the observed present ratio $\rat \sim 2$ to be likely in LCDM, but most likely in QCDM.
1309.3135
Swatantra Tiwari Kumar
S. K. Tiwari, and C. P. Singh
Production of Strange, Non-strange particles and Hypernuclei in an Excluded-Volume Model
4 pages, 5 figures, Invited talk in Strangeness in Quark Matter (SQM)-2013, Birmingham, U.K
null
10.1088/1742-6596/509/1/012097
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a systematic study of production of strange and non-strange hadron yields and their ratios obtained in various experiments using our thermodynamically consistent excluded-volume model. We also analyze the production of light nuclei, hypernuclei and their antinuclei in terms of our excluded-volume model over a broad energy range starting from Alternating Gradient Synchrotron (AGS) to Large Hadron Collider (LHC) energies. Further, we extend our model for studying rapidity spectra of hadrons produced in heavy-ion collisions.
[ { "created": "Thu, 12 Sep 2013 12:26:52 GMT", "version": "v1" } ]
2015-06-17
[ [ "Tiwari", "S. K.", "" ], [ "Singh", "C. P.", "" ] ]
We present a systematic study of production of strange and non-strange hadron yields and their ratios obtained in various experiments using our thermodynamically consistent excluded-volume model. We also analyze the production of light nuclei, hypernuclei and their antinuclei in terms of our excluded-volume model over a broad energy range starting from Alternating Gradient Synchrotron (AGS) to Large Hadron Collider (LHC) energies. Further, we extend our model for studying rapidity spectra of hadrons produced in heavy-ion collisions.
1804.02681
Hanlin Li
Hanlin Li, Zi-Wei Lin, Fuqiang Wang
Charm quarks are more hydrodynamic than light quarks in final-state elliptic flow
10 pages, 4 figures
Phys. Rev. C 99, 044911 (2019)
10.1103/PhysRevC.99.044911
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the charm quark elliptic flow ($v_{2}$) in heavy ion as well as small system collisions by tracking the evolution history of quarks of different flavors within a multi-phase transport model. The charm quark $v_{2}$ is studied as a function of the number of collisions the charm quark suffers with other quarks and then compared to the $v_{2}$ of lighter quarks. We find that the common escape mechanism is at work for both the charm and light quark $v_{2}$. However, contrary to the naive expectation, the hydrodynamics-type flow is found to contribute more to the final state charm $v_{2}$ than light quark $v_{2}$. This could be explained by the smaller average deflection angle the heavier charm quark undergoes in each collision, so that heavy quarks need more scatterings to accumulate a significant $v_{2}$, while lighter quarks can more easily change directions with scatterings with their $v_{2}$ coming more from the escape mechanism. Our finding thus suggests that the charm $v_{2}$ is a better probe for studying the hydrodynamic properties of the quark-gluon plasma.
[ { "created": "Sun, 8 Apr 2018 12:28:00 GMT", "version": "v1" }, { "created": "Fri, 21 Sep 2018 16:10:26 GMT", "version": "v2" } ]
2019-04-24
[ [ "Li", "Hanlin", "" ], [ "Lin", "Zi-Wei", "" ], [ "Wang", "Fuqiang", "" ] ]
We study the charm quark elliptic flow ($v_{2}$) in heavy ion as well as small system collisions by tracking the evolution history of quarks of different flavors within a multi-phase transport model. The charm quark $v_{2}$ is studied as a function of the number of collisions the charm quark suffers with other quarks and then compared to the $v_{2}$ of lighter quarks. We find that the common escape mechanism is at work for both the charm and light quark $v_{2}$. However, contrary to the naive expectation, the hydrodynamics-type flow is found to contribute more to the final state charm $v_{2}$ than light quark $v_{2}$. This could be explained by the smaller average deflection angle the heavier charm quark undergoes in each collision, so that heavy quarks need more scatterings to accumulate a significant $v_{2}$, while lighter quarks can more easily change directions with scatterings with their $v_{2}$ coming more from the escape mechanism. Our finding thus suggests that the charm $v_{2}$ is a better probe for studying the hydrodynamic properties of the quark-gluon plasma.
0705.0803
Wei Qi
K. Hagiwara, W. Qi, C.F. Qiao, J.X. Wang
Re-visiting Direct $J/\psi$ Production at the Fermilab Tevatron
Parallel talk at ICHEP08, Philadelphia, USA, July 2008. 4 pages, LaTeX, 4 eps figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We re-analyze the direct $\jp$ production processes at the Fermilab Tevatron in view of the recent observation at the B-factories, where both $\jp$ inclusive and exclusive production rates are found to be about an order of magnitude larger than the leading order estimates of non-relativistic QCD. The charm quark fragmentation to $\jp$, which is the dominant color-singlet process at high $p_T$, is normalized by the B-factory measurements. The process receives further enhancement due to the charm sea contribution which has so far been ignored in most analyses. After summing up all sub-process contributions, we find that the color-singlet mechanism alone can account for 20% to 90% of the observed direct $\jp$ high $p_T$ production. The polarization rate of the directly produced $\jp$ is sensitive to the fraction of the color-octet contribution, which is employed to fill the gap between the color-singlet prediction and experimental data. With a bigger $K$-factor for the charm quark fragmentation probability, we envisage a smaller matrix element for the color-octet $^3S_1^{(8)}$ state, and this can be examined at the LHC in near future.
[ { "created": "Sun, 6 May 2007 13:35:42 GMT", "version": "v1" }, { "created": "Fri, 9 Nov 2007 00:49:03 GMT", "version": "v2" }, { "created": "Mon, 20 Oct 2008 15:33:49 GMT", "version": "v3" } ]
2008-10-20
[ [ "Hagiwara", "K.", "" ], [ "Qi", "W.", "" ], [ "Qiao", "C. F.", "" ], [ "Wang", "J. X.", "" ] ]
We re-analyze the direct $\jp$ production processes at the Fermilab Tevatron in view of the recent observation at the B-factories, where both $\jp$ inclusive and exclusive production rates are found to be about an order of magnitude larger than the leading order estimates of non-relativistic QCD. The charm quark fragmentation to $\jp$, which is the dominant color-singlet process at high $p_T$, is normalized by the B-factory measurements. The process receives further enhancement due to the charm sea contribution which has so far been ignored in most analyses. After summing up all sub-process contributions, we find that the color-singlet mechanism alone can account for 20% to 90% of the observed direct $\jp$ high $p_T$ production. The polarization rate of the directly produced $\jp$ is sensitive to the fraction of the color-octet contribution, which is employed to fill the gap between the color-singlet prediction and experimental data. With a bigger $K$-factor for the charm quark fragmentation probability, we envisage a smaller matrix element for the color-octet $^3S_1^{(8)}$ state, and this can be examined at the LHC in near future.
hep-ph/9809552
Sreerup Raychaudhuri
Debajyoti Choudhury, Anindya Datta and Sreerup Raychaudhuri
Higgs Boson Signals in Three b-jet Final States at the Fermilab Tevatron
4 pages, 4 postscript figures, RevTeX (style files included)
null
null
CERN-TH/98-316
hep-ph
null
At the Fermilab Tevatron, final states with three tagged b-jets could play an important role in searches for a Higgs boson with mass in the range 100-300 GeV. These signals arise from gb fusion and we demonstrate their observability in the limit of a large b-quark Yukawa coupling. Rather promising discovery limits on such a coupling are obtained and consequent effects on the parameter space of the Higgs-boson sector in the MSSM are discussed.
[ { "created": "Sat, 26 Sep 1998 20:37:31 GMT", "version": "v1" } ]
2007-05-23
[ [ "Choudhury", "Debajyoti", "" ], [ "Datta", "Anindya", "" ], [ "Raychaudhuri", "Sreerup", "" ] ]
At the Fermilab Tevatron, final states with three tagged b-jets could play an important role in searches for a Higgs boson with mass in the range 100-300 GeV. These signals arise from gb fusion and we demonstrate their observability in the limit of a large b-quark Yukawa coupling. Rather promising discovery limits on such a coupling are obtained and consequent effects on the parameter space of the Higgs-boson sector in the MSSM are discussed.
hep-ph/9908474
Marco Fabbrichesi
Stefano Bertolini and Marco Fabbrichesi
Lattice matrix elements confronting the experimental value of eps'/eps
JHEP.cls, 1 figure
JHEP 9910:011,1999
10.1088/1126-6708/1999/10/011
SISSA 102/99/EP
hep-ph
null
A new lattice estimate of K -> 2 pi transitions claims, contrary to all other computations, that the hadronic matrix element for the gluon penguin operator Q_6 has opposite sign and, in addition, is much larger than the vacuum saturation approximation. We comment under what conditions (if any) it is possible to reconcile this lattice result with the experimental value of eps'/eps. The dramatic impact of new physics in the kaon system that seems to be required is not easily accommodated within our present theoretical understanding.
[ { "created": "Thu, 26 Aug 1999 13:34:08 GMT", "version": "v1" }, { "created": "Wed, 8 Sep 1999 14:31:24 GMT", "version": "v2" }, { "created": "Mon, 13 Sep 1999 13:12:26 GMT", "version": "v3" } ]
2010-02-03
[ [ "Bertolini", "Stefano", "" ], [ "Fabbrichesi", "Marco", "" ] ]
A new lattice estimate of K -> 2 pi transitions claims, contrary to all other computations, that the hadronic matrix element for the gluon penguin operator Q_6 has opposite sign and, in addition, is much larger than the vacuum saturation approximation. We comment under what conditions (if any) it is possible to reconcile this lattice result with the experimental value of eps'/eps. The dramatic impact of new physics in the kaon system that seems to be required is not easily accommodated within our present theoretical understanding.
1410.5440
Christoph Englert
Christoph Englert, Yotam Soreq, Michael Spannowsky
Off-Shell Higgs Coupling Measurements in BSM scenarios
11 pages, 9 figures, version published in JHEP
null
null
IPPP/14/91, DCPT/14/182
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Proposals of measuring the off-shell Higgs contributions and first measurements at the LHC have electrified the Higgs phenomenology community for two reasons: Firstly, probing interactions at high invariant masses and momentum transfers is intrinsically sensitive to new physics beyond the Standard Model, irrespective of a resonant or non-resonant character of a particular BSM scenario. Secondly, under specific assumptions a class of models exists for which the off-shell coupling measurement together with a measurement of the on-shell signal strength can be re-interpreted in terms of a bound on the total Higgs boson width. In this paper, we provide a first step towards a classification of the models for which a total width measurement is viable and we discuss examples of BSM models for which the off-shell coupling measurement can be important in either constraining or even discovering new physics in the upcoming LHC runs. Specifically, we discuss the quantitative impact of the presence of dimension six operators on the (de)correlation of Higgs on- and off-shell regions keeping track of all interference effects. We furthermore investigate off-shell measurements in a wider context of new (non-)resonant physics in Higgs portal scenarios and the MSSM.
[ { "created": "Mon, 20 Oct 2014 20:00:48 GMT", "version": "v1" }, { "created": "Tue, 26 May 2015 10:57:54 GMT", "version": "v2" } ]
2015-05-27
[ [ "Englert", "Christoph", "" ], [ "Soreq", "Yotam", "" ], [ "Spannowsky", "Michael", "" ] ]
Proposals of measuring the off-shell Higgs contributions and first measurements at the LHC have electrified the Higgs phenomenology community for two reasons: Firstly, probing interactions at high invariant masses and momentum transfers is intrinsically sensitive to new physics beyond the Standard Model, irrespective of a resonant or non-resonant character of a particular BSM scenario. Secondly, under specific assumptions a class of models exists for which the off-shell coupling measurement together with a measurement of the on-shell signal strength can be re-interpreted in terms of a bound on the total Higgs boson width. In this paper, we provide a first step towards a classification of the models for which a total width measurement is viable and we discuss examples of BSM models for which the off-shell coupling measurement can be important in either constraining or even discovering new physics in the upcoming LHC runs. Specifically, we discuss the quantitative impact of the presence of dimension six operators on the (de)correlation of Higgs on- and off-shell regions keeping track of all interference effects. We furthermore investigate off-shell measurements in a wider context of new (non-)resonant physics in Higgs portal scenarios and the MSSM.
1311.1578
Timothy Hobbs
T. J. Hobbs, J. T. Londergan, and W. Melnitchouk
Phenomenology of nonperturbative charm in the nucleon
50 pages, 12 figures, 3 tables, and 3 appendices
Phys. Rev. D 89, 074008 (2014)
10.1103/PhysRevD.89.074008
JLAB-THY-13-1813
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform a comprehensive analysis of the role of nonperturbative (or intrinsic) charm in the nucleon, generated through Fock state expansions of the nucleon wave function involving five-quark virtual states represented by charmed mesons and baryons. We consider contributions from a variety of charmed meson-baryon states and find surprisingly dominant effects from the (Dbar^{*0} Lambda_c+) configuration. Particular attention is paid to the existence and persistence of high-x structure for intrinsic charm, and the x dependence of the c-cbar asymmetry predicted in meson-baryon models. We discuss how studies of charmed baryons and mesons in hadronic reactions can be used to constrain models, and outline future measurements that could further illuminate the intrinsic charm component of the nucleon.
[ { "created": "Thu, 7 Nov 2013 05:21:16 GMT", "version": "v1" } ]
2014-04-23
[ [ "Hobbs", "T. J.", "" ], [ "Londergan", "J. T.", "" ], [ "Melnitchouk", "W.", "" ] ]
We perform a comprehensive analysis of the role of nonperturbative (or intrinsic) charm in the nucleon, generated through Fock state expansions of the nucleon wave function involving five-quark virtual states represented by charmed mesons and baryons. We consider contributions from a variety of charmed meson-baryon states and find surprisingly dominant effects from the (Dbar^{*0} Lambda_c+) configuration. Particular attention is paid to the existence and persistence of high-x structure for intrinsic charm, and the x dependence of the c-cbar asymmetry predicted in meson-baryon models. We discuss how studies of charmed baryons and mesons in hadronic reactions can be used to constrain models, and outline future measurements that could further illuminate the intrinsic charm component of the nucleon.
1510.09200
David Clark
D.B. Clark
Drell-Yan Production of W/Z at the LHC with Protons and Heavy Nuclei
7 pages, 3 figures, DPF 2015
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Drell-Yan W/Z electroweak boson production at the LHC is an essential standard candle which is used for calibration of beam luminosity and detector properties. In addition to proton-proton collisions, the LHC has measured heavy nuclei lead-lead and proton-lead W/Z production. Inclusion of these data sets in future fits can provide discriminating information of the nuclear modifications present in the Parton Distribution Functions (PDFs). We present an ongoing analysis of W/Z production in lead-lead and proton-lead collisions at the LHC using the \texttt{nCTEQ15} nuclear Parton Distribution Functions (nPDFs) including uncertainties. The cross sections are calculated at NLO with the \texttt{FEWZ\ 2.1} program at 2.76 and 5.02 TeV. We identify promising observables for the observation of the nuclear modifications.
[ { "created": "Fri, 30 Oct 2015 18:57:05 GMT", "version": "v1" } ]
2015-11-02
[ [ "Clark", "D. B.", "" ] ]
Drell-Yan W/Z electroweak boson production at the LHC is an essential standard candle which is used for calibration of beam luminosity and detector properties. In addition to proton-proton collisions, the LHC has measured heavy nuclei lead-lead and proton-lead W/Z production. Inclusion of these data sets in future fits can provide discriminating information of the nuclear modifications present in the Parton Distribution Functions (PDFs). We present an ongoing analysis of W/Z production in lead-lead and proton-lead collisions at the LHC using the \texttt{nCTEQ15} nuclear Parton Distribution Functions (nPDFs) including uncertainties. The cross sections are calculated at NLO with the \texttt{FEWZ\ 2.1} program at 2.76 and 5.02 TeV. We identify promising observables for the observation of the nuclear modifications.
2004.13753
Long Chen
Taushif Ahmed, Werner Bernreuther, Long Chen and Michal Czakon
Polarized $q \bar{q} \rightarrow Z +$Higgs amplitudes at two loops in QCD: the interplay between vector and axial vector form factors and a pitfall in applying a non-anticommuting $\gamma_5$
A few typos fixed along with minor typographic edits, references in the manuscript and the ReadMe.txt updated, matched with the version accepted by JHEP
null
10.1007/JHEP07(2020)159
MPP-2020-37, TTK-20-10, P3H-20-016
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider QCD corrections to two loops for the polarized amplitudes of $q{\bar q}\to Z +$ Higgs boson. First we show how the polarized amplitudes of $b \bar{b} \rightarrow Z h$ associated with a non-vanishing $b$-quark Yukawa coupling and a scalar or pseudoscalar Higgs boson $h$ can be built up solely from vector form factors (FF) of properly grouped classes of diagrams, bypassing completely the need of explicitly manipulating $\gamma_5$ in dimensional regularization (up to a few "anomalous", i.e., triangle diagrams). We determine the contributions of the triangle diagrams in the heavy top limit. We present the analytic results of the vector FF and the triangle-diagram contributions to the axial vector FF, which are sufficient for deriving the two-loop QCD amplitudes for $b \bar{b} \rightarrow Z h$ with a CP-even and CP-odd Higgs boson $h$. We derive the respective Ward identity for these amplitudes, which are subsequently verified to two-loop order in QCD using these FF. In addition, the FF of a class of corrections to $q \bar{q} \rightarrow ZH$ proportional to the top-Yukawa coupling are obtained analytically to two-loop order in QCD in the heavy-top limit using the Higgs-gluon effective Lagrangian where the top quark is integrated out. We address a pitfall that occurs when applying the non-anticommutating $\gamma_5$ prescription to this class of contributions that has been overlooked so far in the literature. We attribute this issue to the fact that the absence of certain heavy-mass expanded diagrams in the infinite-mass limit of a scattering amplitude with an axial vector current depends on the particular $\gamma_5$ prescription in use.
[ { "created": "Tue, 28 Apr 2020 18:01:39 GMT", "version": "v1" }, { "created": "Tue, 14 Jul 2020 11:16:06 GMT", "version": "v2" } ]
2020-08-26
[ [ "Ahmed", "Taushif", "" ], [ "Bernreuther", "Werner", "" ], [ "Chen", "Long", "" ], [ "Czakon", "Michal", "" ] ]
We consider QCD corrections to two loops for the polarized amplitudes of $q{\bar q}\to Z +$ Higgs boson. First we show how the polarized amplitudes of $b \bar{b} \rightarrow Z h$ associated with a non-vanishing $b$-quark Yukawa coupling and a scalar or pseudoscalar Higgs boson $h$ can be built up solely from vector form factors (FF) of properly grouped classes of diagrams, bypassing completely the need of explicitly manipulating $\gamma_5$ in dimensional regularization (up to a few "anomalous", i.e., triangle diagrams). We determine the contributions of the triangle diagrams in the heavy top limit. We present the analytic results of the vector FF and the triangle-diagram contributions to the axial vector FF, which are sufficient for deriving the two-loop QCD amplitudes for $b \bar{b} \rightarrow Z h$ with a CP-even and CP-odd Higgs boson $h$. We derive the respective Ward identity for these amplitudes, which are subsequently verified to two-loop order in QCD using these FF. In addition, the FF of a class of corrections to $q \bar{q} \rightarrow ZH$ proportional to the top-Yukawa coupling are obtained analytically to two-loop order in QCD in the heavy-top limit using the Higgs-gluon effective Lagrangian where the top quark is integrated out. We address a pitfall that occurs when applying the non-anticommutating $\gamma_5$ prescription to this class of contributions that has been overlooked so far in the literature. We attribute this issue to the fact that the absence of certain heavy-mass expanded diagrams in the infinite-mass limit of a scattering amplitude with an axial vector current depends on the particular $\gamma_5$ prescription in use.
2009.13237
Vladimir Galkin
R.N. Faustov, V.O. Galkin, E.M. Savchenko
Masses of the $QQ\bar Q\bar Q$ tetraquarks in the relativistic diquark--antidiquark picture
12 pages, references added, published version
Phys. Rev. D 102, 114030 (2020)
10.1103/PhysRevD.102.114030
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Masses of the ground-state teraquarks composed from heavy $c$ and $b$ quarks and antiquarks are calculated in the diquark-antidiquark picture in the framework of the relativistic quark model based on the quasipotential approach. The quasipotentials of the quark-quark and diquark-antidiquark interactions are constructed similarly to the previous consideration of mesons and baryons. It is assumed that the diquark and antidiquark interact in the tetraquark as a whole and the internal structure of the diquarks is taken into account. All such tetraquarks are found above the thresholds of decays to two heavy quarkonia. This is a result of the consideration of the diquark not to be a point-like object. Therefore such tetraquarks can be observed as broad structures decaying dominantly to quarkonia. The broad structure next to the di-$J/\psi$ mass threshold, recently observed by the LHCb Collaboration, can correspond to the ground $2^{++}$-state tetraquark consisting of four charm quarks.
[ { "created": "Mon, 28 Sep 2020 12:05:02 GMT", "version": "v1" }, { "created": "Mon, 11 Jan 2021 14:07:07 GMT", "version": "v2" } ]
2021-01-12
[ [ "Faustov", "R. N.", "" ], [ "Galkin", "V. O.", "" ], [ "Savchenko", "E. M.", "" ] ]
Masses of the ground-state teraquarks composed from heavy $c$ and $b$ quarks and antiquarks are calculated in the diquark-antidiquark picture in the framework of the relativistic quark model based on the quasipotential approach. The quasipotentials of the quark-quark and diquark-antidiquark interactions are constructed similarly to the previous consideration of mesons and baryons. It is assumed that the diquark and antidiquark interact in the tetraquark as a whole and the internal structure of the diquarks is taken into account. All such tetraquarks are found above the thresholds of decays to two heavy quarkonia. This is a result of the consideration of the diquark not to be a point-like object. Therefore such tetraquarks can be observed as broad structures decaying dominantly to quarkonia. The broad structure next to the di-$J/\psi$ mass threshold, recently observed by the LHCb Collaboration, can correspond to the ground $2^{++}$-state tetraquark consisting of four charm quarks.
1109.6631
Marco Matone
Marco Matone
Superluminality and a Curious Phenomenon in the Relativistic Quantum Hamilton-Jacobi Equation
5 pages
Phys.Scripta 86 (2012) 055007
10.1088/0031-8949/86/05/055007
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A basic problem in the relativistic quantum Hamilton-Jacobi theory is to understand whether it may admit superluminal solutions. Here we consider the averaging of the speed on a period of the oscillating term which is similar to Dirac's averaging of the oscillating part of the free electron's speed. Such an averaging solves the problem of getting the $\hbar\to 0$ limit of the speed of the free particle, and leads to solutions that, depending on the integration constants, may be superluminal.
[ { "created": "Thu, 29 Sep 2011 19:20:37 GMT", "version": "v1" }, { "created": "Tue, 11 Oct 2011 18:58:37 GMT", "version": "v2" }, { "created": "Sun, 16 Dec 2012 11:14:05 GMT", "version": "v3" } ]
2018-06-20
[ [ "Matone", "Marco", "" ] ]
A basic problem in the relativistic quantum Hamilton-Jacobi theory is to understand whether it may admit superluminal solutions. Here we consider the averaging of the speed on a period of the oscillating term which is similar to Dirac's averaging of the oscillating part of the free electron's speed. Such an averaging solves the problem of getting the $\hbar\to 0$ limit of the speed of the free particle, and leads to solutions that, depending on the integration constants, may be superluminal.
2207.06060
Zhi-Gang Wang
Xiu-Wu Wang, Zhi-Gang Wang
Analysis of the $P_{cs}(4338)$ and related pentaquark molecular states via the QCD sum rules
20 pages, 5 figures
Chin. Phys. C47 (2023) 013109
10.1088/1674-1137/ac9aab
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this work, we tentatively identify the $P_{cs}(4338)$ as the $\bar{D}\Xi_c$ molecular state, and distinguish the isospins of the current operators to explore the $\bar{D}\Xi_c$, $\bar{D}\Lambda_c$, $\bar{D}_s\Xi_c$, $\bar{D}_s\Lambda_c$, $\bar{D}^*\Xi_c$, $\bar{D}^*\Lambda_c$, $\bar{D}^*_s\Xi_c$ and $\bar{D}^*_s\Lambda_c$ molecular states without strange, with strange and with double strange in the framework of the QCD sum rules in details. The present explorations favor identifying the $P_{cs}(4338)$ ($P_{cs}(4459)$) as the $\bar{D}\Xi_c$ ($\bar{D}^*\Xi_c$) molecular state with the spin-parity $J^P={\frac{1}{2}}^-$ (${\frac{3}{2}}^-$) and isospin $(I,I_3)=(0,0)$, the observation of their cousins with the isospin $(I,I_3)=(1,0)$ in the $J/\psi\Sigma^0/\eta_c\Sigma^0$ invariant mass distributions would decipher their inner structures.
[ { "created": "Wed, 13 Jul 2022 09:07:31 GMT", "version": "v1" }, { "created": "Mon, 1 Aug 2022 14:18:24 GMT", "version": "v2" }, { "created": "Wed, 3 Aug 2022 14:27:30 GMT", "version": "v3" }, { "created": "Sun, 4 Sep 2022 03:33:27 GMT", "version": "v4" }, { "crea...
2022-11-28
[ [ "Wang", "Xiu-Wu", "" ], [ "Wang", "Zhi-Gang", "" ] ]
In this work, we tentatively identify the $P_{cs}(4338)$ as the $\bar{D}\Xi_c$ molecular state, and distinguish the isospins of the current operators to explore the $\bar{D}\Xi_c$, $\bar{D}\Lambda_c$, $\bar{D}_s\Xi_c$, $\bar{D}_s\Lambda_c$, $\bar{D}^*\Xi_c$, $\bar{D}^*\Lambda_c$, $\bar{D}^*_s\Xi_c$ and $\bar{D}^*_s\Lambda_c$ molecular states without strange, with strange and with double strange in the framework of the QCD sum rules in details. The present explorations favor identifying the $P_{cs}(4338)$ ($P_{cs}(4459)$) as the $\bar{D}\Xi_c$ ($\bar{D}^*\Xi_c$) molecular state with the spin-parity $J^P={\frac{1}{2}}^-$ (${\frac{3}{2}}^-$) and isospin $(I,I_3)=(0,0)$, the observation of their cousins with the isospin $(I,I_3)=(1,0)$ in the $J/\psi\Sigma^0/\eta_c\Sigma^0$ invariant mass distributions would decipher their inner structures.
1105.4594
Ciaran Williams
John M. Campbell, Adam Martin, Ciaran Williams
NLO predictions for a lepton, missing transverse momentum and dijets at the Tevatron
4 pages, 5 figures
Phys.Rev.D84:036005,2011
10.1103/PhysRevD.84.036005
FERMILAB-PUB-11-218-T
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
n this letter we investigate the various processes that can contribute to a final state consisting of a lepton, missing transverse momentum and two jets at Next to Leading Order (NLO) at the Tevatron. In particular we consider the production of W/Z + 2 jets, diboson pairs, single top and the tt process with both fully leptonic and semi-leptonic decays. We present distributions for the invariant mass of the dijet system and normalisations of the various processes, accurate to NLO.
[ { "created": "Mon, 23 May 2011 19:39:46 GMT", "version": "v1" } ]
2015-03-19
[ [ "Campbell", "John M.", "" ], [ "Martin", "Adam", "" ], [ "Williams", "Ciaran", "" ] ]
n this letter we investigate the various processes that can contribute to a final state consisting of a lepton, missing transverse momentum and two jets at Next to Leading Order (NLO) at the Tevatron. In particular we consider the production of W/Z + 2 jets, diboson pairs, single top and the tt process with both fully leptonic and semi-leptonic decays. We present distributions for the invariant mass of the dijet system and normalisations of the various processes, accurate to NLO.