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0707.4319
Omar Gustavo Miranda
J. Barranco, O. G. Miranda, T. I. Rashba
Improved limit on electron neutrino charge radius through a new evaluation of the weak mixing angle
10 pages, 2 figures. Final published version
Phys.Lett.B662:431-435,2008
10.1016/j.physletb.2008.03.039
MPP-2007-99
hep-ph hep-ex
null
We have obtained a new limit on the electron neutrino effective charge radius from a new evaluation of the weak mixing angle by a combined fit of all electron-(anti)neutrino electron elastic scattering measurements. Weak mixing angle is found to be sin^2 theta_W=0.259 \pm 0.025 in the low energy regime below 100 MeV. The electron neutrino charge radius squared is bounded to be in the range -0.13 10^-32 cm^2 < r^2 < 3.32 10^-32 cm^2 at 90 % C.L. Both results improve previously published analyses. We also discuss perspectives of future experiments to improve these constraints.
[ { "created": "Sun, 29 Jul 2007 21:40:38 GMT", "version": "v1" }, { "created": "Mon, 24 Mar 2008 22:31:27 GMT", "version": "v2" }, { "created": "Tue, 22 Apr 2008 16:00:26 GMT", "version": "v3" } ]
2008-11-26
[ [ "Barranco", "J.", "" ], [ "Miranda", "O. G.", "" ], [ "Rashba", "T. I.", "" ] ]
We have obtained a new limit on the electron neutrino effective charge radius from a new evaluation of the weak mixing angle by a combined fit of all electron-(anti)neutrino electron elastic scattering measurements. Weak mixing angle is found to be sin^2 theta_W=0.259 \pm 0.025 in the low energy regime below 100 MeV. The electron neutrino charge radius squared is bounded to be in the range -0.13 10^-32 cm^2 < r^2 < 3.32 10^-32 cm^2 at 90 % C.L. Both results improve previously published analyses. We also discuss perspectives of future experiments to improve these constraints.
1010.0841
Gennady Lykasov I
V.A.Bednyakov, G.I.Lykasov, M.G.Poghosyan
Gluons in proton and soft pp collisions at high energies
Talk given at the workshop "Hadron Structure and QCD: from LOW to High energies", Gatchina, Russia, July 5-9, 2010; 8 pages, 4 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The hadron inclusive spectra in pp collisions at high energies are analyzed within a soft QCD model, namely the quark-gluon string model. In addition to the sea quark distribution in the incoming proton we consider also the unintegrated gluon distribution that has an increasing behaviour when the gluon transverse momentum grows. It leads to an increase of the inclusive spectra of hadrons and their multiplicity in the central rapidity region of pp collision at LHC energies.
[ { "created": "Tue, 5 Oct 2010 11:05:40 GMT", "version": "v1" } ]
2015-03-17
[ [ "Bednyakov", "V. A.", "" ], [ "Lykasov", "G. I.", "" ], [ "Poghosyan", "M. G.", "" ] ]
The hadron inclusive spectra in pp collisions at high energies are analyzed within a soft QCD model, namely the quark-gluon string model. In addition to the sea quark distribution in the incoming proton we consider also the unintegrated gluon distribution that has an increasing behaviour when the gluon transverse momentum grows. It leads to an increase of the inclusive spectra of hadrons and their multiplicity in the central rapidity region of pp collision at LHC energies.
0705.4097
Gary Shiu
Gary Shiu, Bret Underwood, Devin G.E. Walker, Kathryn M. Zurek
Probing the Geometry of Warped String Compactifications at the LHC
4 pages, 4 figures; v2. typos corrected, references added, improved resolution of Figure 2
Phys.Rev.Lett.100:031601,2008
10.1103/PhysRevLett.100.031601
MAD-TH-07-08, MADPH-07-1491, UCB-PTH-07/08
hep-ph astro-ph hep-ex hep-th
null
Warped string compactifications, characterized by non-singular behavior of the metric in the infrared (IR), feature departures from the usual anti-de Sitter warped extra dimensions. We study the implications of the smooth IR cutoff for Randall-Sundrum (RS) type models. We find that the phenomenology of the KK gravitons (including their masses and couplings) depends sensitively on the precise shape of the warp factor in the IR. In particular, we analyze the warped deformed conifold and find that the spectrum differs significantly from that of RS, and present a simple prescription (a mass gap ansatz) which can be used to study the phenomenology of IR modifications to 5-d warped extra dimensions.
[ { "created": "Mon, 28 May 2007 21:03:39 GMT", "version": "v1" }, { "created": "Thu, 10 Jan 2008 19:21:55 GMT", "version": "v2" } ]
2008-11-26
[ [ "Shiu", "Gary", "" ], [ "Underwood", "Bret", "" ], [ "Walker", "Devin G. E.", "" ], [ "Zurek", "Kathryn M.", "" ] ]
Warped string compactifications, characterized by non-singular behavior of the metric in the infrared (IR), feature departures from the usual anti-de Sitter warped extra dimensions. We study the implications of the smooth IR cutoff for Randall-Sundrum (RS) type models. We find that the phenomenology of the KK gravitons (including their masses and couplings) depends sensitively on the precise shape of the warp factor in the IR. In particular, we analyze the warped deformed conifold and find that the spectrum differs significantly from that of RS, and present a simple prescription (a mass gap ansatz) which can be used to study the phenomenology of IR modifications to 5-d warped extra dimensions.
1603.01072
Artur Ankowski
Artur M. Ankowski, Omar Benhar, Camillo Mariani, and Erica Vagnoni
Effect of the $2p2h$ cross-section uncertainties on an analysis of neutrino oscillations
7 pages, 5 figures
Phys. Rev. D 93, 113004 (2016)
10.1103/PhysRevD.93.113004
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report the results of a study aimed at quantifying the impact on the oscillation analysis of the uncertainties associated with the description of the neutrino-nucleus cross section in the two-particle--two-hole sector. The results of our calculations, based on the kinematic method of energy reconstruction and carried out comparing two data-driven approaches, show that the existing discrepancies in the neutrino cross sections have a sizable effect on the extracted oscillation parameters, particularly in the antineutrino channel.
[ { "created": "Thu, 3 Mar 2016 12:25:33 GMT", "version": "v1" }, { "created": "Wed, 8 Jun 2016 01:40:07 GMT", "version": "v2" } ]
2016-06-09
[ [ "Ankowski", "Artur M.", "" ], [ "Benhar", "Omar", "" ], [ "Mariani", "Camillo", "" ], [ "Vagnoni", "Erica", "" ] ]
We report the results of a study aimed at quantifying the impact on the oscillation analysis of the uncertainties associated with the description of the neutrino-nucleus cross section in the two-particle--two-hole sector. The results of our calculations, based on the kinematic method of energy reconstruction and carried out comparing two data-driven approaches, show that the existing discrepancies in the neutrino cross sections have a sizable effect on the extracted oscillation parameters, particularly in the antineutrino channel.
0709.0161
Hagop Sazdjian
H. Sazdjian
Integral equation for gauge invariant quark two-point Green's function in QCD
28 pages, 4 figures
Phys.Rev.D77:045028,2008
10.1103/PhysRevD.77.045028
IPNO-DR-07-03
hep-ph
null
Gauge invariant quark two-point Green's functions defined with path-ordered gluon field phase factors along skew-polygonal lines joining the quark to the antiquark are considered. Functional relations between Green's functions with different numbers of path segments are established. An integral equation is obtained for the Green's function defined with a phase factor along a single straight line. The equation implicates an infinite series of two-point Green's functions, having an increasing number of path segments; the related kernels involve Wilson loops with contours corresponding to the skew-polygonal lines of the accompanying Green's function and with functional derivatives along the sides of the contours. The series can be viewed as an expansion in terms of the global number of the functional derivatives of the Wilson loops. The lowest-order kernel, which involves a Wilson loop with two functional derivatives, provides the framework for an approximate resolution of the equation.
[ { "created": "Mon, 3 Sep 2007 08:17:04 GMT", "version": "v1" } ]
2008-11-26
[ [ "Sazdjian", "H.", "" ] ]
Gauge invariant quark two-point Green's functions defined with path-ordered gluon field phase factors along skew-polygonal lines joining the quark to the antiquark are considered. Functional relations between Green's functions with different numbers of path segments are established. An integral equation is obtained for the Green's function defined with a phase factor along a single straight line. The equation implicates an infinite series of two-point Green's functions, having an increasing number of path segments; the related kernels involve Wilson loops with contours corresponding to the skew-polygonal lines of the accompanying Green's function and with functional derivatives along the sides of the contours. The series can be viewed as an expansion in terms of the global number of the functional derivatives of the Wilson loops. The lowest-order kernel, which involves a Wilson loop with two functional derivatives, provides the framework for an approximate resolution of the equation.
hep-ph/9405387
Jutta Kunz
Burkhard Kleihaus and Jutta Kunz
Multisphalerons in the Weinberg-Salam Theory
18 pages, latex, 17 figures in uuencoded postscript files. THU-94/11
Phys.Rev. D50 (1994) 5343-5351
10.1103/PhysRevD.50.5343
null
hep-ph
null
We construct multisphaleron solutions in the Weinberg-Salam theory. The multisphaleron solutions carry Chern-Simons charge $n/2$, where $n$ is an integer, counting the winding of the fields in the azimuthal angle. The well-known sphaleron has $n=1$. The multisphalerons possess axial symmetry and parity reflection symmetry. We vary the Higgs mass and the mixing angle. For small $n$ the energies of the multisphalerons are on the order of $n$ times the energy of the sphaleron and their magnetic dipole moments are on the order of $n$ times the magnetic dipole moment of the sphaleron.
[ { "created": "Thu, 26 May 1994 12:56:46 GMT", "version": "v1" } ]
2009-10-28
[ [ "Kleihaus", "Burkhard", "" ], [ "Kunz", "Jutta", "" ] ]
We construct multisphaleron solutions in the Weinberg-Salam theory. The multisphaleron solutions carry Chern-Simons charge $n/2$, where $n$ is an integer, counting the winding of the fields in the azimuthal angle. The well-known sphaleron has $n=1$. The multisphalerons possess axial symmetry and parity reflection symmetry. We vary the Higgs mass and the mixing angle. For small $n$ the energies of the multisphalerons are on the order of $n$ times the energy of the sphaleron and their magnetic dipole moments are on the order of $n$ times the magnetic dipole moment of the sphaleron.
hep-ph/9303216
J. Gunion
John F. Gunion, T.C. Yuan, and B. Grzadkowski
Gluon Fusion: A Probe of Higgs Sector CP Violation
UCD-93-2
Phys.Rev.Lett.71:488-491,1993; ERRATUM-ibid.71:2681,1993
10.1103/PhysRevLett.71.488
null
hep-ph
null
We demonstrate that CP violation in the Higgs sector, \eg\ of a multi-doublet model, can be directly probed using gluon-gluon collisions at the SSC. % requires phyzzx.tex macro package
[ { "created": "Wed, 3 Mar 1993 16:27:00 GMT", "version": "v1" } ]
2010-11-01
[ [ "Gunion", "John F.", "" ], [ "Yuan", "T. C.", "" ], [ "Grzadkowski", "B.", "" ] ]
We demonstrate that CP violation in the Higgs sector, \eg\ of a multi-doublet model, can be directly probed using gluon-gluon collisions at the SSC. % requires phyzzx.tex macro package
hep-ph/9307235
Evan Reidell
Xiangdong Ji
Chiral-Odd and Spin-Dependent Quark Fragmentation Functions and their Applications
19 pages in Plain TeX, MIT CTP #2219
Phys.Rev. D49 (1994) 114-124
10.1103/PhysRevD.49.114
null
hep-ph
null
We define a number of quark fragmentation functions for spin-0, -1/2 and -1 hadrons, and classify them according to their twist, spin and chirality. As an example of their applications, we use them to analyze semi-inclusive deep-inelastic scattering on a transversely polarized nucleon.
[ { "created": "Thu, 8 Jul 1993 19:48:49 GMT", "version": "v1" } ]
2009-10-22
[ [ "Ji", "Xiangdong", "" ] ]
We define a number of quark fragmentation functions for spin-0, -1/2 and -1 hadrons, and classify them according to their twist, spin and chirality. As an example of their applications, we use them to analyze semi-inclusive deep-inelastic scattering on a transversely polarized nucleon.
2005.00109
Philip D. Mannheim
Philip D. Mannheim, Peter Lowdon and Stanley J. Brodsky
Comparing light-front quantization with instant-time quantization
72 pages, 2 figures. Expanded version of arXiv:1909.03548, includes discussion of light-front Lehmann representation and connection between light-front and instant-time Hamiltonians
null
null
SLAC-PUB-17390
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compare light-front quantization and instant-time quantization both at the level of operators and at the level of their Feynman diagram matrix elements. At the level of operators light-front quantization and instant-time quantization lead to equal light-front time commutation (or anticommutation) relations that appear to be quite different from equal instant-time commutation (or anticommutation) relations. Despite this we show that at unequal times instant-time and light-front commutation (or anticommutation) relations actually can be transformed into each other, with it only being the restriction to equal times that makes the commutation (or anticommutation) relations appear to be so different. While our results are valid for both bosons and fermions, for fermions there are subtleties associated with tip of the light cone contributions that need to be taken care of. At the level of Feynman diagrams we show for non-vacuum Feynman diagrams that the pole terms in four-dimensional light-front Feynman diagrams reproduce the three-dimensional light-front on-shell Hamiltonian Fock space formulation in which the light-front energy and light-front momentum are on shell. However, because of circle at infinity contributions we show that this equivalence fails for four-dimensional light-front vacuum tadpole diagrams. Then, precisely because of these circle at infinity contributions, light-front vacuum tadpole diagrams are not only nonzero, they are actually equal to instant-time vacuum tadpole diagrams. Light-front vacuum diagrams are not correctly describable by the on-shell Hamiltonian formalism, and thus not by the closely related infinite momentum frame prescription either. With the transformation from instant-time fields to light-front fields being a spacetime translation, not only are instant-time quantization and light-front quantization equivalent, they are unitarily equivalent.
[ { "created": "Thu, 30 Apr 2020 21:15:19 GMT", "version": "v1" }, { "created": "Fri, 3 Jul 2020 20:32:11 GMT", "version": "v2" } ]
2020-09-01
[ [ "Mannheim", "Philip D.", "" ], [ "Lowdon", "Peter", "" ], [ "Brodsky", "Stanley J.", "" ] ]
We compare light-front quantization and instant-time quantization both at the level of operators and at the level of their Feynman diagram matrix elements. At the level of operators light-front quantization and instant-time quantization lead to equal light-front time commutation (or anticommutation) relations that appear to be quite different from equal instant-time commutation (or anticommutation) relations. Despite this we show that at unequal times instant-time and light-front commutation (or anticommutation) relations actually can be transformed into each other, with it only being the restriction to equal times that makes the commutation (or anticommutation) relations appear to be so different. While our results are valid for both bosons and fermions, for fermions there are subtleties associated with tip of the light cone contributions that need to be taken care of. At the level of Feynman diagrams we show for non-vacuum Feynman diagrams that the pole terms in four-dimensional light-front Feynman diagrams reproduce the three-dimensional light-front on-shell Hamiltonian Fock space formulation in which the light-front energy and light-front momentum are on shell. However, because of circle at infinity contributions we show that this equivalence fails for four-dimensional light-front vacuum tadpole diagrams. Then, precisely because of these circle at infinity contributions, light-front vacuum tadpole diagrams are not only nonzero, they are actually equal to instant-time vacuum tadpole diagrams. Light-front vacuum diagrams are not correctly describable by the on-shell Hamiltonian formalism, and thus not by the closely related infinite momentum frame prescription either. With the transformation from instant-time fields to light-front fields being a spacetime translation, not only are instant-time quantization and light-front quantization equivalent, they are unitarily equivalent.
2106.09598
Eugenio Megias
Eugenio Megias, Mariano Quiros
Analytical Green's Functions for Continuum Spectra
46 pages, 16 figures; v2 extended version: added reference [52] and Fig. 15, extended discussion in Secs. 2, 3.1, 3.3, 3.4 and Appendix A. Typos corrected. It matches the version published in Journal of High Energy Physics
null
10.1007/JHEP09(2021)157
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Green's functions with continuum spectra are a way of avoiding the strong bounds on new physics from the absence of new narrow resonances in experimental data. We model such a situation with a five-dimensional model with two branes along the extra dimension $z$, the ultraviolet (UV) and the infrared (IR) one, such that the metric between the UV and the IR brane is AdS$_5$, thus solving the hierarchy problem, and beyond the IR brane the metric is that of a linear dilaton model, which extends to $z\to\infty$. This simplified metric, which can be considered as an approximation of a more complicated (and smooth) one, leads to analytical Green's functions (with a mass gap $m_g \sim \textrm{TeV}$ and a continuum for $s > m_g^2$) which could then be easily incorporated in the experimental codes. The theory contains Standard Model gauge bosons in the bulk with Neumann boundary conditions in the UV brane. To cope with electroweak observables the theory is also endowed with an extra custodial gauge symmetry in the bulk, with gauge bosons with Dirichlet boundary conditions in the UV brane, and without zero (massless) modes. All Green's functions have analytical expressions and exhibit poles in the second Riemann sheet of the complex plane at $s=M_n^2-i M_n\Gamma_n$, denoting a discrete (infinite) set of broad resonances with masses ($M_n$) and widths ($\Gamma_n$). For gauge bosons with Neumann or Dirichlet boundary conditions, the masses and widths of resonances satisfy the (approximate) equation $s= - 4 m_g^2 \mathcal W_n^2[\pm (1+i)/4]$, where $\mathcal W_n$ is the $n$-th branch of the Lambert function.
[ { "created": "Thu, 17 Jun 2021 15:29:58 GMT", "version": "v1" }, { "created": "Sat, 25 Sep 2021 14:59:32 GMT", "version": "v2" } ]
2021-10-13
[ [ "Megias", "Eugenio", "" ], [ "Quiros", "Mariano", "" ] ]
Green's functions with continuum spectra are a way of avoiding the strong bounds on new physics from the absence of new narrow resonances in experimental data. We model such a situation with a five-dimensional model with two branes along the extra dimension $z$, the ultraviolet (UV) and the infrared (IR) one, such that the metric between the UV and the IR brane is AdS$_5$, thus solving the hierarchy problem, and beyond the IR brane the metric is that of a linear dilaton model, which extends to $z\to\infty$. This simplified metric, which can be considered as an approximation of a more complicated (and smooth) one, leads to analytical Green's functions (with a mass gap $m_g \sim \textrm{TeV}$ and a continuum for $s > m_g^2$) which could then be easily incorporated in the experimental codes. The theory contains Standard Model gauge bosons in the bulk with Neumann boundary conditions in the UV brane. To cope with electroweak observables the theory is also endowed with an extra custodial gauge symmetry in the bulk, with gauge bosons with Dirichlet boundary conditions in the UV brane, and without zero (massless) modes. All Green's functions have analytical expressions and exhibit poles in the second Riemann sheet of the complex plane at $s=M_n^2-i M_n\Gamma_n$, denoting a discrete (infinite) set of broad resonances with masses ($M_n$) and widths ($\Gamma_n$). For gauge bosons with Neumann or Dirichlet boundary conditions, the masses and widths of resonances satisfy the (approximate) equation $s= - 4 m_g^2 \mathcal W_n^2[\pm (1+i)/4]$, where $\mathcal W_n$ is the $n$-th branch of the Lambert function.
2012.14575
Yu-Kuo Hsiao
Yao Yu and Yu-Kuo Hsiao
Cabibbo-favored $\Lambda^+_c\to\Lambda a_{0}(980)^+$ decay in the final state interaction
10 pages, 2 figures, version to appear in Physics Letters B
null
10.1016/j.physletb.2021.136586
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The anti-triplet charmed baryon decays with the light scalar mesons are rarely measured, whereas the recent observation of the Cabibbo-favored $\Lambda_c^+\to \Lambda\eta\pi^+$ decay hints a possible $\Lambda_c^+\to\Lambda a_0(980)^+,a_0(980)^+\to \eta\pi^+$ process. We hence study the $\Lambda_c^+\to\Lambda a_0(980)^+$ decay. Particularly, it is found that the final state interaction can give a significant contribution, where $\Sigma^{+}(1385)$ and $\eta$ in $\Lambda_c^+\to \Sigma^{+}(1385)\eta$ by exchanging a charged pion are transformed as $\Lambda$ and $a_0(980)^+$, respectively. Accordingly, we predict ${\cal B}(\Lambda_c^+\to\Lambda a_0(980)^+)=(1.7^{+2.8}_{-1.0}\pm 0.3)\times 10^{-3}$, accessible to the BESIII, BELLEII and LHCb experiments.
[ { "created": "Tue, 29 Dec 2020 02:45:34 GMT", "version": "v1" }, { "created": "Sat, 21 Aug 2021 06:17:02 GMT", "version": "v2" } ]
2021-08-25
[ [ "Yu", "Yao", "" ], [ "Hsiao", "Yu-Kuo", "" ] ]
The anti-triplet charmed baryon decays with the light scalar mesons are rarely measured, whereas the recent observation of the Cabibbo-favored $\Lambda_c^+\to \Lambda\eta\pi^+$ decay hints a possible $\Lambda_c^+\to\Lambda a_0(980)^+,a_0(980)^+\to \eta\pi^+$ process. We hence study the $\Lambda_c^+\to\Lambda a_0(980)^+$ decay. Particularly, it is found that the final state interaction can give a significant contribution, where $\Sigma^{+}(1385)$ and $\eta$ in $\Lambda_c^+\to \Sigma^{+}(1385)\eta$ by exchanging a charged pion are transformed as $\Lambda$ and $a_0(980)^+$, respectively. Accordingly, we predict ${\cal B}(\Lambda_c^+\to\Lambda a_0(980)^+)=(1.7^{+2.8}_{-1.0}\pm 0.3)\times 10^{-3}$, accessible to the BESIII, BELLEII and LHCb experiments.
1806.08597
Mohammad Athar SAJJAD
A. Fatima, M. Sajjad Athar, and S. K. Singh
Second class currents and T violation in quasielastic neutrino and antineutrino scattering from nucleons
29 pages, 17 figures, 1 table
Phys. Rev. D 98, 033005 (2018)
10.1103/PhysRevD.98.033005
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The effect of the second class currents with and without time reversal invariance has been studied in the quasielastic production of nucleons and hyperons induced by neutrinos and antineutrinos from the nucleons. The numerical results are presented for the total scattering cross section~($\sigma$) as well as for the longitudinal, perpendicular and transverse components of the polarization of the final baryons ($p$, $n$, $\Lambda$, $\Sigma^-$, $\Sigma^0$) and muon produced in the quasielastic (anti)neutrino-nucleon scattering induced by the weak charged current. In the case of the production of $\Lambda$ hyperon, which is the most suitable candidate for making the polarization measurements, we have also calculated the $Q^2$ dependence of the polarization observables and the differential scattering cross section ($d\sigma/dQ^2$). The measurement of the polarization observables and their $Q^2$ dependence provides an independent way to determine the nucleon-hyperon transition form factors at high $Q^2$ which can provide tests of the symmetries of the weak hadronic currents like G-invariance, T invariance and SU(3) symmetry.
[ { "created": "Fri, 22 Jun 2018 11:02:32 GMT", "version": "v1" }, { "created": "Fri, 16 Nov 2018 07:39:52 GMT", "version": "v2" } ]
2018-11-19
[ [ "Fatima", "A.", "" ], [ "Athar", "M. Sajjad", "" ], [ "Singh", "S. K.", "" ] ]
The effect of the second class currents with and without time reversal invariance has been studied in the quasielastic production of nucleons and hyperons induced by neutrinos and antineutrinos from the nucleons. The numerical results are presented for the total scattering cross section~($\sigma$) as well as for the longitudinal, perpendicular and transverse components of the polarization of the final baryons ($p$, $n$, $\Lambda$, $\Sigma^-$, $\Sigma^0$) and muon produced in the quasielastic (anti)neutrino-nucleon scattering induced by the weak charged current. In the case of the production of $\Lambda$ hyperon, which is the most suitable candidate for making the polarization measurements, we have also calculated the $Q^2$ dependence of the polarization observables and the differential scattering cross section ($d\sigma/dQ^2$). The measurement of the polarization observables and their $Q^2$ dependence provides an independent way to determine the nucleon-hyperon transition form factors at high $Q^2$ which can provide tests of the symmetries of the weak hadronic currents like G-invariance, T invariance and SU(3) symmetry.
1909.00375
Maciej Rybczynski
Maksym Deliyergiyev and Maciej Rybczynski
Multiplicity fluctuations in the Glauber Monte Carlo approach
18 pages, 8 figures
Phys. Rev. C 101, 014909 (2020)
10.1103/PhysRevC.101.014909
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss multiplicity fluctuations of charged particles produced in nuclear collisions measured event-by-event by the NA49 experiment at CERN SPS within the Glauber Monte Carlo approach. We use the concepts of wounded nucleons and wounded quarks in the mechanism of multiparticle production to characterize multiplicity fluctuations expressed by the scaled variance of multiplicity distribution. Although Wounded Nucleon Model correctly reproduce the centrality dependence of the average multiplicity in Pb+Pb collisions, it completely fails in description of corresponding centrality dependence of scaled variance of multiplicity distribution. Using subnucleonic degrees of freedom, i.e. wounded quarks within Wounded Quark Model, it is possible to describe quite well the multiplicity distribution of charged particles produced in proton+proton interactions. However, the Wounded Quark Model with parameters describing multiplicity distribution of particles produced in proton+proton interactions substantially exceeds the average multiplicity of charged particles produced in Pb+Pb collisions. To obtain values of average multiplicities close to those experimentally measured in Pb+Pb collisions, the concept of shadowed quark sources is implemented. Wounded Quark Model with implemented shadowing source scenario reproduces the centrality dependence of scaled variance of multiplicity distribution of charged particles produced in Pb+Pb collisions in the range from the most central to mid-peripheral interactions.
[ { "created": "Sun, 1 Sep 2019 10:44:48 GMT", "version": "v1" } ]
2020-01-22
[ [ "Deliyergiyev", "Maksym", "" ], [ "Rybczynski", "Maciej", "" ] ]
We discuss multiplicity fluctuations of charged particles produced in nuclear collisions measured event-by-event by the NA49 experiment at CERN SPS within the Glauber Monte Carlo approach. We use the concepts of wounded nucleons and wounded quarks in the mechanism of multiparticle production to characterize multiplicity fluctuations expressed by the scaled variance of multiplicity distribution. Although Wounded Nucleon Model correctly reproduce the centrality dependence of the average multiplicity in Pb+Pb collisions, it completely fails in description of corresponding centrality dependence of scaled variance of multiplicity distribution. Using subnucleonic degrees of freedom, i.e. wounded quarks within Wounded Quark Model, it is possible to describe quite well the multiplicity distribution of charged particles produced in proton+proton interactions. However, the Wounded Quark Model with parameters describing multiplicity distribution of particles produced in proton+proton interactions substantially exceeds the average multiplicity of charged particles produced in Pb+Pb collisions. To obtain values of average multiplicities close to those experimentally measured in Pb+Pb collisions, the concept of shadowed quark sources is implemented. Wounded Quark Model with implemented shadowing source scenario reproduces the centrality dependence of scaled variance of multiplicity distribution of charged particles produced in Pb+Pb collisions in the range from the most central to mid-peripheral interactions.
hep-ph/0110368
Michael Beyer
S. Mattiello, M. Beyer (Rostock U), T. Frederico (Sao Paulo, Inst. Tech. Aeronautics), H. J. Weber (Virginia U.)
Correlations in hot and dense quark matter
6 pages, 4 figure, Few-Body Systems style files
Few Body Syst. 31 (2002) 159-164
10.1007/s006010200015
null
hep-ph
null
We present a relativistic three-body equation to investigate three-quark clusters in hot and dense quark matter. To derive such an equation we use the Dyson equation approach. The equation systematically includes the Pauli blocking factors as well as the self energy corrections of quarks. Special relativity is realized through the light front form. Presently we use a zero-range force and investigate the Mott transition.
[ { "created": "Mon, 29 Oct 2001 15:22:03 GMT", "version": "v1" } ]
2009-11-07
[ [ "Mattiello", "S.", "", "Rostock U" ], [ "Beyer", "M.", "", "Rostock U" ], [ "Frederico", "T.", "", "Sao Paulo, Inst.\n Tech. Aeronautics" ], [ "Weber", "H. J.", "", "Virginia U." ] ]
We present a relativistic three-body equation to investigate three-quark clusters in hot and dense quark matter. To derive such an equation we use the Dyson equation approach. The equation systematically includes the Pauli blocking factors as well as the self energy corrections of quarks. Special relativity is realized through the light front form. Presently we use a zero-range force and investigate the Mott transition.
2306.08453
Juan Marchant Gonz\'alez
Cesar Bonilla, A. E. C\'arcamo Hern\'andez, Basti\'an D\'iaz S\'aez, Sergey Kovalenko and Juan Marchant Gonz\'alez
Dark Matter from a Radiative Inverse Seesaw Majoron Model
15 pages, 6 figures
Physics Letters B, 847, 138282 (2023)
10.1016/j.physletb.2023.138282
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
We propose a Majoron-like extension of the Standard Model with an extra global $U(1)_X$-symmetry where neutrino masses are generated through an inverse seesaw mechanism at the 1-loop level. In contrast to the tree-level inverse seesaw, our framework contains dark matter (DM) candidates stabilized by a residual $\mathcal{Z}_2$-symmetry surviving spontaneous breaking of the $U(1)_X$-group. We explore the case in which the DM is a Majorana fermion. Furthermore, we provide parameter space regions allowed by current experimental constraints coming from the dark matter relic abundance, (in)direct detection, and charged lepton flavor violation.
[ { "created": "Wed, 14 Jun 2023 11:54:17 GMT", "version": "v1" }, { "created": "Mon, 15 Jan 2024 00:27:06 GMT", "version": "v2" } ]
2024-01-17
[ [ "Bonilla", "Cesar", "" ], [ "Hernández", "A. E. Cárcamo", "" ], [ "Sáez", "Bastián Díaz", "" ], [ "Kovalenko", "Sergey", "" ], [ "González", "Juan Marchant", "" ] ]
We propose a Majoron-like extension of the Standard Model with an extra global $U(1)_X$-symmetry where neutrino masses are generated through an inverse seesaw mechanism at the 1-loop level. In contrast to the tree-level inverse seesaw, our framework contains dark matter (DM) candidates stabilized by a residual $\mathcal{Z}_2$-symmetry surviving spontaneous breaking of the $U(1)_X$-group. We explore the case in which the DM is a Majorana fermion. Furthermore, we provide parameter space regions allowed by current experimental constraints coming from the dark matter relic abundance, (in)direct detection, and charged lepton flavor violation.
2403.04987
Jia-Zhi Huang
Jia-Zhi Huang, Yu-Feng Zhou
Constraints on evaporating primordial black holes from the AMS-02 positron data
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Cosmic-ray (CR) positrons are relatively rare due to its secondary origin and thus sensitive to exotic contributions. Primordial black holes (PBHs) with masses above $\sim 5\times10^{14}\,\mathrm{g}$ can be stable sources of CR positrons due to Hawking radiation. We show that the CR positron flux measured by AMS-02 can place stringent constraints on the energy fraction of PBHs relative to that of dark matter $f_{\text{PBH}}$. Making use of the state-of-the-art models for CR propagation in both the Galaxy and heliosphere, we obtain conservative upper limit of $f_{\text{PBH}}\lesssim3\times 10^{-4}$ at $M_{\mathrm{PBH}}\simeq2\times 10^{16}$ g, which improves the previous constraints obtained from the Voyager CR all-electron data by around an order of magnitude.
[ { "created": "Fri, 8 Mar 2024 01:59:51 GMT", "version": "v1" } ]
2024-03-11
[ [ "Huang", "Jia-Zhi", "" ], [ "Zhou", "Yu-Feng", "" ] ]
Cosmic-ray (CR) positrons are relatively rare due to its secondary origin and thus sensitive to exotic contributions. Primordial black holes (PBHs) with masses above $\sim 5\times10^{14}\,\mathrm{g}$ can be stable sources of CR positrons due to Hawking radiation. We show that the CR positron flux measured by AMS-02 can place stringent constraints on the energy fraction of PBHs relative to that of dark matter $f_{\text{PBH}}$. Making use of the state-of-the-art models for CR propagation in both the Galaxy and heliosphere, we obtain conservative upper limit of $f_{\text{PBH}}\lesssim3\times 10^{-4}$ at $M_{\mathrm{PBH}}\simeq2\times 10^{16}$ g, which improves the previous constraints obtained from the Voyager CR all-electron data by around an order of magnitude.
hep-ph/0701027
Richard Lemmer
R. H. Lemmer
Calculation of the two-photon decay width of the f_0(980) scalar meson
14 pages, 3 figures. Fig.3 replaced. Additional remarks with references
Phys.Lett.B650:152-158,2007
10.1016/j.physletb.2007.03.071
null
hep-ph
null
The applicability of the quasi-static approximation for calculating the two-photon annihilation rate of the scalar f_0(980) meson envisaged as a K\bar K molecule is critically re-examined. It is shown that the validity of this approximation depends on the detailed interplay between the momentum dependence of the annihilation amplitude and the momentum transform of the bound state wave function of the annihilating pair. The approximation becomes invalid when these two scales of variation are similar. An improved method of calculation based on the inclusion of electromagnetic corrections to the kernel of the Bethe-Salpeter equation for the interacting K\bar K pair is outlined to cover this case and applied to re-evaluate the two-photon decay width for f_0(980) in a one boson exchange model for the interkaon interaction. The corrections are significant and result in a much better agreement with experiment.
[ { "created": "Thu, 4 Jan 2007 11:47:59 GMT", "version": "v1" }, { "created": "Tue, 20 Mar 2007 11:35:18 GMT", "version": "v2" }, { "created": "Wed, 21 Nov 2007 08:07:17 GMT", "version": "v3" } ]
2008-11-26
[ [ "Lemmer", "R. H.", "" ] ]
The applicability of the quasi-static approximation for calculating the two-photon annihilation rate of the scalar f_0(980) meson envisaged as a K\bar K molecule is critically re-examined. It is shown that the validity of this approximation depends on the detailed interplay between the momentum dependence of the annihilation amplitude and the momentum transform of the bound state wave function of the annihilating pair. The approximation becomes invalid when these two scales of variation are similar. An improved method of calculation based on the inclusion of electromagnetic corrections to the kernel of the Bethe-Salpeter equation for the interacting K\bar K pair is outlined to cover this case and applied to re-evaluate the two-photon decay width for f_0(980) in a one boson exchange model for the interkaon interaction. The corrections are significant and result in a much better agreement with experiment.
1901.05822
Mathias Pierre
Mathias Pierre
Dark Matter phenomenology : from simplified WIMP models to refined alternative solutions
PhD Thesis, 273 pages
null
null
2018SACLS238
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
One of the most puzzling problems of modern physics is the identification of the nature a non-relativistic matter component present in the universe, contributing to more than 25$\%$ of the total energy budget, known as Dark Matter. Weakly Interacting Massive Particles (WIMPs) are among the best motivated dark matter candidates. However, in light of non conclusive detection signals and strong constraints from collider, direct and indirect detection experiments, this thesis presents constraints on several realizations of the WIMP paradigm in the context of simplified dark matter models. More elaborated models considering extended gauge structures are discussed further on, such as constructions involving generalized Chern-Simons couplings and a specific WIMP scenario motivated by recently observed flavour anomalies related to the $R_{K^{(*)}}$ observable. The second part of this thesis is devoted to the discussion of an alternative dark matter thermal production mechanism where an explicit realization of the Strongly Interacting Massive Particles (SIMPs) paradigm is discussed in the context of a non-Abelian hidden gauge structure. In a last part, the possibility of producing non-thermally a dark matter component via the "freeze-in" mechanism was investigated and the strong impact of the post-inflationary reaheating stage of the universe on such constructions illustrated by the specific case where dark matter density production is mediated by a heavy spin-2 field in addition to the standard graviton.
[ { "created": "Thu, 17 Jan 2019 14:58:02 GMT", "version": "v1" } ]
2019-01-18
[ [ "Pierre", "Mathias", "" ] ]
One of the most puzzling problems of modern physics is the identification of the nature a non-relativistic matter component present in the universe, contributing to more than 25$\%$ of the total energy budget, known as Dark Matter. Weakly Interacting Massive Particles (WIMPs) are among the best motivated dark matter candidates. However, in light of non conclusive detection signals and strong constraints from collider, direct and indirect detection experiments, this thesis presents constraints on several realizations of the WIMP paradigm in the context of simplified dark matter models. More elaborated models considering extended gauge structures are discussed further on, such as constructions involving generalized Chern-Simons couplings and a specific WIMP scenario motivated by recently observed flavour anomalies related to the $R_{K^{(*)}}$ observable. The second part of this thesis is devoted to the discussion of an alternative dark matter thermal production mechanism where an explicit realization of the Strongly Interacting Massive Particles (SIMPs) paradigm is discussed in the context of a non-Abelian hidden gauge structure. In a last part, the possibility of producing non-thermally a dark matter component via the "freeze-in" mechanism was investigated and the strong impact of the post-inflationary reaheating stage of the universe on such constructions illustrated by the specific case where dark matter density production is mediated by a heavy spin-2 field in addition to the standard graviton.
1509.02406
Rados{\l}aw Kycia
S. Jadach and R.A. Kycia
Lineshape of the Higgs boson in future lepton colliders
18 pages, 7 figures; added new references
null
10.1016/j.physletb.2016.01.065
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The effect of the photon emission (bremsstrahlung) in the cross section of the process of direct production of the Higgs boson in the future high luminosity electron and muon colliders is calculated. It was found that cross section at the top of the Higgs boson resonance peak is reduced by factor 0.347 for the electron collider and 0.548 for the muon collider. Machine spread of the centre of the mass energy of 4.2MeV (equal to the Higgs width) would reduce peak cross section further, by factor 0.170 and 0.256 (QED and energy spread) for electron and muon beams respectively. Possible uncertainties in the resummed QED calculations are discussed. Numerical results for the lineshape cross section including QED and many values of the machine energy spread are provided.
[ { "created": "Tue, 8 Sep 2015 15:13:12 GMT", "version": "v1" }, { "created": "Tue, 22 Sep 2015 17:13:53 GMT", "version": "v2" } ]
2016-02-10
[ [ "Jadach", "S.", "" ], [ "Kycia", "R. A.", "" ] ]
The effect of the photon emission (bremsstrahlung) in the cross section of the process of direct production of the Higgs boson in the future high luminosity electron and muon colliders is calculated. It was found that cross section at the top of the Higgs boson resonance peak is reduced by factor 0.347 for the electron collider and 0.548 for the muon collider. Machine spread of the centre of the mass energy of 4.2MeV (equal to the Higgs width) would reduce peak cross section further, by factor 0.170 and 0.256 (QED and energy spread) for electron and muon beams respectively. Possible uncertainties in the resummed QED calculations are discussed. Numerical results for the lineshape cross section including QED and many values of the machine energy spread are provided.
1206.2296
Paolo Gambino
Paolo Gambino, Thomas Mannel and Nikolai Uraltsev
B-> D* zero-recoil formfactor and the heavy quark expansion in QCD: a systematic study
70 pages, 13 figures
null
10.1007/JHEP10(2012)169
SI-HEP-2011-15; UND-HEP-12-BIG10
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a QCD analysis of heavy quark mesons focussing on the B -> D* formfactor at zero recoil, F_D*(1). An advanced treatment of the perturbative corrections in the Wilsonian approach is presented. We estimate the higher-order power corrections to the OPE sum rule and describe a refined analysis of the nonresonant continuum contribution. In the framework of a model-independent approach, we show that the inelastic contribution in the phenomenological part of the OPE is related to the mQ-dependence of the hyperfine splitting and conclude that the former is large, lowering the prediction for F_D*(1) down to about 0.86. This likewise implies an enhanced yield of radial and D-wave charm excitations in semileptonic B decays and alleviates the problem with the inclusive yield of the wide excited states. We also apply the approach to the expectation values of dimension 7 and 8 local operators and to a few other issues in the heavy quark expansion.
[ { "created": "Mon, 11 Jun 2012 17:32:50 GMT", "version": "v1" } ]
2015-06-05
[ [ "Gambino", "Paolo", "" ], [ "Mannel", "Thomas", "" ], [ "Uraltsev", "Nikolai", "" ] ]
We present a QCD analysis of heavy quark mesons focussing on the B -> D* formfactor at zero recoil, F_D*(1). An advanced treatment of the perturbative corrections in the Wilsonian approach is presented. We estimate the higher-order power corrections to the OPE sum rule and describe a refined analysis of the nonresonant continuum contribution. In the framework of a model-independent approach, we show that the inelastic contribution in the phenomenological part of the OPE is related to the mQ-dependence of the hyperfine splitting and conclude that the former is large, lowering the prediction for F_D*(1) down to about 0.86. This likewise implies an enhanced yield of radial and D-wave charm excitations in semileptonic B decays and alleviates the problem with the inclusive yield of the wide excited states. We also apply the approach to the expectation values of dimension 7 and 8 local operators and to a few other issues in the heavy quark expansion.
hep-ph/0002059
Virendra Gupta
V. Gupta
A new approach to the parametrization of the Cabibbo-Kobayashi-Maskawa matrix
8 pages, latex, no figures
Int.J.Mod.Phys.A16:1645,2001
10.1142/S0217751X01003603
null
hep-ph
null
The CKM-matrix V is written as a linear combination of the unit matrix I and a matrix U which causes intergenerational-mixing. It is shown that such a V results from a class of quark-mass matrices. The matrix U has to be hermitian and unitary and therefore can depend at most on 4 real parameters. The available data on the CKM-matrix including CP-violation can be reproduced by $V=(I+iU)/\sqrt{2}$. This is also true for the special case when U depends on \textit{only 2 real parameters}. There is no CP-violating phase in this parametrization. Also, for such a V the invariant phase $\Phi \equiv \phi _{12}+\phi_{23}-\phi_{13}$, satisfies a criterion suggested for `maximal' CP-violation.
[ { "created": "Fri, 4 Feb 2000 21:56:04 GMT", "version": "v1" } ]
2010-11-23
[ [ "Gupta", "V.", "" ] ]
The CKM-matrix V is written as a linear combination of the unit matrix I and a matrix U which causes intergenerational-mixing. It is shown that such a V results from a class of quark-mass matrices. The matrix U has to be hermitian and unitary and therefore can depend at most on 4 real parameters. The available data on the CKM-matrix including CP-violation can be reproduced by $V=(I+iU)/\sqrt{2}$. This is also true for the special case when U depends on \textit{only 2 real parameters}. There is no CP-violating phase in this parametrization. Also, for such a V the invariant phase $\Phi \equiv \phi _{12}+\phi_{23}-\phi_{13}$, satisfies a criterion suggested for `maximal' CP-violation.
1609.08922
Daniel Are\'an
Daniel Arean, Ioannis Iatrakis, Matti Jarvinen, Elias Kiritsis
The CP-odd sector and $\theta$ dynamics in holographic QCD
58 pages plus appendices, 19 figures. V2: section 3.1 improved, typos corrected, published version
Phys. Rev. D 96, 026001 (2017)
10.1103/PhysRevD.96.026001
CCQCN-2016-151, CCTP-2016-8, MPP-2016-167
hep-ph hep-lat hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The holographic model of V-QCD is used to analyze the physics of QCD in the Veneziano large-N limit. An unprecedented analysis of the CP-odd physics is performed going beyond the level of effective field theories. The structure of holographic saddle-points at finite $\theta$ is determined, as well as its interplay with chiral symmetry breaking. Many observables (vacuum energy and higher-order susceptibilities, singlet and non-singlet masses and mixings) are computed as functions of $\theta$ and the quark mass $m$. Wherever applicable the results are compared to those of chiral Lagrangians, finding agreement. In particular, we recover the Witten-Veneziano formula in the small $x\to 0$ limit, we compute the $\theta$-dependence of the pion mass and we derive the hyperscaling relation for the topological susceptibility in the conformal window in terms of the quark mass.
[ { "created": "Wed, 28 Sep 2016 14:18:03 GMT", "version": "v1" }, { "created": "Tue, 26 Sep 2017 14:27:18 GMT", "version": "v2" } ]
2017-09-27
[ [ "Arean", "Daniel", "" ], [ "Iatrakis", "Ioannis", "" ], [ "Jarvinen", "Matti", "" ], [ "Kiritsis", "Elias", "" ] ]
The holographic model of V-QCD is used to analyze the physics of QCD in the Veneziano large-N limit. An unprecedented analysis of the CP-odd physics is performed going beyond the level of effective field theories. The structure of holographic saddle-points at finite $\theta$ is determined, as well as its interplay with chiral symmetry breaking. Many observables (vacuum energy and higher-order susceptibilities, singlet and non-singlet masses and mixings) are computed as functions of $\theta$ and the quark mass $m$. Wherever applicable the results are compared to those of chiral Lagrangians, finding agreement. In particular, we recover the Witten-Veneziano formula in the small $x\to 0$ limit, we compute the $\theta$-dependence of the pion mass and we derive the hyperscaling relation for the topological susceptibility in the conformal window in terms of the quark mass.
2103.12089
Matthew Sullivan
Hooman Davoudiasl, Ian M. Lewis, Matthew Sullivan
Multi-TeV Signals of Baryogenesis in Higgs Troika Model
v3: EDM estimate revised; conclusions unchanged
Phys. Rev. D 104, 015024 (2021)
10.1103/PhysRevD.104.015024
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A modest extension of the Standard Model by two additional Higgs doublets - the Higgs Troika Model - can provide a well-motivated scenario for successful baryogenesis if neutrinos are Dirac fermions. Adapting the "Spontaneous Flavor Violation" framework, we consider a version of the Troika model where light quarks have significant couplings to the new multi-TeV Higgs states. Resonant production of new scalars leading to di-jet or top-pair signals are typical predictions of this setup. The initial and final state quarks relevant to the collider phenomenology also play a key role in baryogenesis, potentially providing direct access to the relevant early Universe physics in high energy experiments. Viable baryogenesis generally prefers some hierarchy of masses between the observed and the postulated Higgs states. We show that there is a complementarity between direct searches at a future 100 TeV $pp$ collider and indirect searches at flavor experiments, with both sensitive to different regions of parameter space relevant for baryogenesis. In particular, measurements of $D-\bar{D}$ mixing at LHCb probe much of the interesting parameter space. Direct and indirect searches can uncover the new Higgs states up to masses of $\mathcal{O}(10)$ TeV, thereby providing an impressive reach to investigate this model.
[ { "created": "Mon, 22 Mar 2021 18:00:09 GMT", "version": "v1" }, { "created": "Fri, 30 Jul 2021 18:06:13 GMT", "version": "v2" }, { "created": "Fri, 25 Feb 2022 21:55:36 GMT", "version": "v3" } ]
2022-03-01
[ [ "Davoudiasl", "Hooman", "" ], [ "Lewis", "Ian M.", "" ], [ "Sullivan", "Matthew", "" ] ]
A modest extension of the Standard Model by two additional Higgs doublets - the Higgs Troika Model - can provide a well-motivated scenario for successful baryogenesis if neutrinos are Dirac fermions. Adapting the "Spontaneous Flavor Violation" framework, we consider a version of the Troika model where light quarks have significant couplings to the new multi-TeV Higgs states. Resonant production of new scalars leading to di-jet or top-pair signals are typical predictions of this setup. The initial and final state quarks relevant to the collider phenomenology also play a key role in baryogenesis, potentially providing direct access to the relevant early Universe physics in high energy experiments. Viable baryogenesis generally prefers some hierarchy of masses between the observed and the postulated Higgs states. We show that there is a complementarity between direct searches at a future 100 TeV $pp$ collider and indirect searches at flavor experiments, with both sensitive to different regions of parameter space relevant for baryogenesis. In particular, measurements of $D-\bar{D}$ mixing at LHCb probe much of the interesting parameter space. Direct and indirect searches can uncover the new Higgs states up to masses of $\mathcal{O}(10)$ TeV, thereby providing an impressive reach to investigate this model.
2008.07959
Li-Sheng Geng
Yin Huang, Jun-Xu Lu, Ju-Jun Xie, and Li-Sheng Geng
Strong decays of $\bar{D}^{*}K^{*}$ molecules and the newly observed $X_{0,1}$ states
5 pages, 2 figures
null
10.1140/epjc/s10052-020-08516-4
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Lately, the LHCb Collaboration reported the discovery of two new states in the $B^+\rightarrow D^+D^- K^+$ decay, i.e., $X_0(2866)$ and $X_1(2904)$. In the present work, we study whether these states can be understood as $D^*\bar{K}^*$ molecules from the perspective of their two-body strong decays into $D^-K^+$ via triangle diagrams and three-body decays into $D^*\bar{K}\pi$. The coupling of the two states to $D^*\bar{K}^*$ are determined from the Weinberg compositeness condition, while the other relevant couplings are well known. The obtained strong decay width for the $X_0(2866)$, in marginal agreement with the experimental value within the uncertainty of the model, hints at a large $D^*\bar{K}^*$ component in its wave function. On the other hand, the strong decay width for the $X_1(2904)$, much smaller than its experimental counterpart, effectively rules out its assignment as a $D^*\bar{K}^*$ molecule.
[ { "created": "Tue, 18 Aug 2020 14:42:58 GMT", "version": "v1" } ]
2020-12-02
[ [ "Huang", "Yin", "" ], [ "Lu", "Jun-Xu", "" ], [ "Xie", "Ju-Jun", "" ], [ "Geng", "Li-Sheng", "" ] ]
Lately, the LHCb Collaboration reported the discovery of two new states in the $B^+\rightarrow D^+D^- K^+$ decay, i.e., $X_0(2866)$ and $X_1(2904)$. In the present work, we study whether these states can be understood as $D^*\bar{K}^*$ molecules from the perspective of their two-body strong decays into $D^-K^+$ via triangle diagrams and three-body decays into $D^*\bar{K}\pi$. The coupling of the two states to $D^*\bar{K}^*$ are determined from the Weinberg compositeness condition, while the other relevant couplings are well known. The obtained strong decay width for the $X_0(2866)$, in marginal agreement with the experimental value within the uncertainty of the model, hints at a large $D^*\bar{K}^*$ component in its wave function. On the other hand, the strong decay width for the $X_1(2904)$, much smaller than its experimental counterpart, effectively rules out its assignment as a $D^*\bar{K}^*$ molecule.
0708.2007
Elsayed Lashin Dr.
H. A. Alhendi, E. I. Lashin and A. A. Mudlej
Textures with two traceless submatrices of the neutrino mass matrix
17 pages, 3 figures and 2 tables, Minor typos are corrected
Phys.Rev.D77:013009,2008
10.1103/PhysRevD.77.013009
null
hep-ph
null
We propose a new texture for the light neutrino mass matrix. The proposal is based upon imposing zero-trace condition on the two by two sub-matrices of the complex symmetric Majorana mass matrix in the flavor basis where the charged lepton mass matrix is diagonal. Restricting the mass matrix to have two traceless sub-matrices may be found sufficient to describe the current data. Eight out of fifteen independent possible cases are found to be compatible with current data. Numerical and some approximate analytical results are presented.
[ { "created": "Wed, 15 Aug 2007 10:53:06 GMT", "version": "v1" }, { "created": "Wed, 27 Feb 2008 21:50:24 GMT", "version": "v2" } ]
2008-11-26
[ [ "Alhendi", "H. A.", "" ], [ "Lashin", "E. I.", "" ], [ "Mudlej", "A. A.", "" ] ]
We propose a new texture for the light neutrino mass matrix. The proposal is based upon imposing zero-trace condition on the two by two sub-matrices of the complex symmetric Majorana mass matrix in the flavor basis where the charged lepton mass matrix is diagonal. Restricting the mass matrix to have two traceless sub-matrices may be found sufficient to describe the current data. Eight out of fifteen independent possible cases are found to be compatible with current data. Numerical and some approximate analytical results are presented.
1808.04634
Tianjun Li
Tianjun Li
The Generalized Abelian and Non-Abelian Gauge Theories and their Particle Physics Applications
5 pages
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Gauge theory is the foundation of the particle physics Standard Model (SM). Considering the multiple gauge sectors for one gauge transformation, we study the generalized Abelian and non-Abelian (Yang-Mills theory) gauge theories. We first point out that the U(1) gauge theory has a few unique properties, which provide the motivations for the generalized Yang-Mills theory. Also, we consider the generalized Abelian gauge theory, and study the Higgs mechanism with new interesting properties. In addition, we propose the simple and generic generalizations of Yang-Mills theory. In the simple generalization, we realize two specific properties in the Abelian gauge theory. For applications in particle physics, we propose the invisible axion model with TeV-scale Peceei-Quinn symmetry breaking. We can solve the strong CP problem, and obtain the effective decay constant around the intermediate scale. Moreover, we study the SM electroweak symmetry breaking induced from the symmetry breaking in the other gauge Sector. In particular, we can easily obtain the strong first order electroweak phase transition in the SM, which is important for electroweak baryogenesis and gravitational wave.
[ { "created": "Tue, 14 Aug 2018 11:32:41 GMT", "version": "v1" } ]
2018-08-15
[ [ "Li", "Tianjun", "" ] ]
Gauge theory is the foundation of the particle physics Standard Model (SM). Considering the multiple gauge sectors for one gauge transformation, we study the generalized Abelian and non-Abelian (Yang-Mills theory) gauge theories. We first point out that the U(1) gauge theory has a few unique properties, which provide the motivations for the generalized Yang-Mills theory. Also, we consider the generalized Abelian gauge theory, and study the Higgs mechanism with new interesting properties. In addition, we propose the simple and generic generalizations of Yang-Mills theory. In the simple generalization, we realize two specific properties in the Abelian gauge theory. For applications in particle physics, we propose the invisible axion model with TeV-scale Peceei-Quinn symmetry breaking. We can solve the strong CP problem, and obtain the effective decay constant around the intermediate scale. Moreover, we study the SM electroweak symmetry breaking induced from the symmetry breaking in the other gauge Sector. In particular, we can easily obtain the strong first order electroweak phase transition in the SM, which is important for electroweak baryogenesis and gravitational wave.
2309.00054
Andreas Von Manteuffel
Roman N. Lee, Andreas von Manteuffel, Robert M. Schabinger, Alexander V. Smirnov, Vladimir A. Smirnov, Matthias Steinhauser
Master Integrals for Four-Loop Massless Form Factors
17 pages, 3 figures, files with analytical results at https://www.ttp.kit.edu/preprints/2023/ttp23-034/
null
null
MSUHEP-23-023, P3H-23-057, TTP23-034
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present analytical results for all master integrals for massless three-point functions, with one off-shell leg, at four loops. Our solutions were obtained using differential equations and direct integration techniques. We review the methods and provide additional details.
[ { "created": "Thu, 31 Aug 2023 18:00:45 GMT", "version": "v1" } ]
2023-09-04
[ [ "Lee", "Roman N.", "" ], [ "von Manteuffel", "Andreas", "" ], [ "Schabinger", "Robert M.", "" ], [ "Smirnov", "Alexander V.", "" ], [ "Smirnov", "Vladimir A.", "" ], [ "Steinhauser", "Matthias", "" ] ]
We present analytical results for all master integrals for massless three-point functions, with one off-shell leg, at four loops. Our solutions were obtained using differential equations and direct integration techniques. We review the methods and provide additional details.
hep-ph/9708476
David London
David London
New Physics and the Unitarity Triangle
8 pages, Latex, requires aipproc.sty (included), 1 PS figure (included)
null
10.1063/1.55105
UdeM-GPP-TH-97-44
hep-ph
null
After reviewing the present experimental constraints on the unitarity triangle, I discuss the various ways in which new physics can manifest itself in measurements of the parameters of the unitarity triangle. Apart from one exception, which I describe, new physics enters principally through new contributions to B0-B0(bar) mixing. Different models of new physics can be partially distinguished by looking at their effects on rare, flavour-changing $B$ penguin decays. (Invited talk given at the Symposium Twenty Beautiful Years of Bottom Physics, Chicago, IL, USA, June 29 -- July 2, 1997.)
[ { "created": "Wed, 27 Aug 1997 16:12:25 GMT", "version": "v1" } ]
2009-10-30
[ [ "London", "David", "" ] ]
After reviewing the present experimental constraints on the unitarity triangle, I discuss the various ways in which new physics can manifest itself in measurements of the parameters of the unitarity triangle. Apart from one exception, which I describe, new physics enters principally through new contributions to B0-B0(bar) mixing. Different models of new physics can be partially distinguished by looking at their effects on rare, flavour-changing $B$ penguin decays. (Invited talk given at the Symposium Twenty Beautiful Years of Bottom Physics, Chicago, IL, USA, June 29 -- July 2, 1997.)
hep-ph/0403155
V. V. Sinev
G. Domogatski, V. Kopeikin, L. Mikaelyan, V. Sinev
Inverse beta decay reaction in $^{232}$Th and $^{233}$U fission antineutrino flux
6 pages in LaTeX and 2 ps figures. Submitted to Physics of Atomic Nuclei
Phys.Atom.Nucl.68:234-236,2005; Yad.Fiz.68:259-261,2005
10.1134/1.1866378
null
hep-ph
null
Energy spectra of antineutrinos coming from $^{232}$Th and $^{233}$U neutron-induced fission are calculated, relevant inverse beta decay $\bar{{\nu}_e}+p \to n + e^{+}$ positron spectra and total cross sections are found. This study is stimulated by a hypothesis that a self-sustained nuclear chain reaction is burning at the center of the Earth ("Georeactor"). The Georeactor, according to the author of this idea, provides energy necessary to sustain the Earth's magnetic field. The Georeactor's nuclear fuel is $^{235}$U and, probably, $^{232}$Th and $^{233}$U. Results of present study may appear to be useful in future experiments aimed to test the Georector hypothesis and to estimate its fuel components as a part of developments in geophysics and astrophysics based on observations of low energy antineutrinos in Nature.
[ { "created": "Mon, 15 Mar 2004 08:14:32 GMT", "version": "v1" }, { "created": "Wed, 17 Mar 2004 06:54:26 GMT", "version": "v2" } ]
2008-11-26
[ [ "Domogatski", "G.", "" ], [ "Kopeikin", "V.", "" ], [ "Mikaelyan", "L.", "" ], [ "Sinev", "V.", "" ] ]
Energy spectra of antineutrinos coming from $^{232}$Th and $^{233}$U neutron-induced fission are calculated, relevant inverse beta decay $\bar{{\nu}_e}+p \to n + e^{+}$ positron spectra and total cross sections are found. This study is stimulated by a hypothesis that a self-sustained nuclear chain reaction is burning at the center of the Earth ("Georeactor"). The Georeactor, according to the author of this idea, provides energy necessary to sustain the Earth's magnetic field. The Georeactor's nuclear fuel is $^{235}$U and, probably, $^{232}$Th and $^{233}$U. Results of present study may appear to be useful in future experiments aimed to test the Georector hypothesis and to estimate its fuel components as a part of developments in geophysics and astrophysics based on observations of low energy antineutrinos in Nature.
hep-ph/0502105
John F. Gunion
Radovan Dermisek and John F. Gunion
Escaping the Large Fine Tuning and Little Hierarchy Problems in the Next to Minimal Supersymmetric Model and h-> aa Decays
4 pages, 4 figures, revised to conform with PRL published version
Phys.Rev.Lett.95:041801,2005
10.1103/PhysRevLett.95.041801
null
hep-ph hep-ex
null
We demonstrate that the NMSSM can have small fine tuning and modest light stop mass while still evading all experimental constraints. For small tan(beta) [large tan(beta)], the relevant scenarios are such that there is always (often) a SM-like Higgs boson that decays to two lighter -- possibly much lighter -- pseudoscalar Higgses.
[ { "created": "Fri, 11 Feb 2005 01:35:06 GMT", "version": "v1" }, { "created": "Thu, 14 Jul 2005 17:09:59 GMT", "version": "v2" } ]
2014-11-18
[ [ "Dermisek", "Radovan", "" ], [ "Gunion", "John F.", "" ] ]
We demonstrate that the NMSSM can have small fine tuning and modest light stop mass while still evading all experimental constraints. For small tan(beta) [large tan(beta)], the relevant scenarios are such that there is always (often) a SM-like Higgs boson that decays to two lighter -- possibly much lighter -- pseudoscalar Higgses.
hep-ph/9908491
Kaustubh Agashe
Kaustubh Agashe (UC Berkeley and LBNL)
Naturalness and Supersymmetry
LaTeX, 154 pages, figures. Ph.D. thesis (UC Berkeley, May 1998)
null
null
LBNL-41874
hep-ph
null
Supersymmetry solves the gauge hierarchy problem of the Standard Model if the masses of supersymmetric partners of the SM particles are close to the weak scale. In this thesis, we argue that the supersymmetric Standard Model, while avoiding the fine tuning in electroweak symmetry breaking, requires unnaturalness/fine tuning in some (other) sector of the theory. For example, Baryon and Lepton number violating operators are allowed which lead to proton decay and flavor changing neutral currents. We study some of the constraints from the latter in this thesis. We have to impose an R-parity for the theory to be both natural and viable. In the absence of flavor symmetries, the supersymmetry breaking masses for the squarks and sleptons lead to too large flavor changing neutral currents. We show that two of the solutions to this problem, gauge mediation of supersymmetry breaking and making the scalars of the first two generations heavier than a few TeV, reintroduce fine tuning in electroweak symmetry breaking. We also construct a model of low energy gauge mediation with a non-minimal messenger sector which improves the fine tuning and also generates required Higgs mass terms. We show that this model can be derived from a Grand Unified Theory despite the non-minimal spectrum.
[ { "created": "Fri, 27 Aug 1999 22:55:10 GMT", "version": "v1" } ]
2007-05-23
[ [ "Agashe", "Kaustubh", "", "UC Berkeley and LBNL" ] ]
Supersymmetry solves the gauge hierarchy problem of the Standard Model if the masses of supersymmetric partners of the SM particles are close to the weak scale. In this thesis, we argue that the supersymmetric Standard Model, while avoiding the fine tuning in electroweak symmetry breaking, requires unnaturalness/fine tuning in some (other) sector of the theory. For example, Baryon and Lepton number violating operators are allowed which lead to proton decay and flavor changing neutral currents. We study some of the constraints from the latter in this thesis. We have to impose an R-parity for the theory to be both natural and viable. In the absence of flavor symmetries, the supersymmetry breaking masses for the squarks and sleptons lead to too large flavor changing neutral currents. We show that two of the solutions to this problem, gauge mediation of supersymmetry breaking and making the scalars of the first two generations heavier than a few TeV, reintroduce fine tuning in electroweak symmetry breaking. We also construct a model of low energy gauge mediation with a non-minimal messenger sector which improves the fine tuning and also generates required Higgs mass terms. We show that this model can be derived from a Grand Unified Theory despite the non-minimal spectrum.
hep-ph/0204127
Xiaomin Zu
John C. Collins, Xiaomin Zu
Parton Distribution Functions suitable for Monte-Carlo event generators
References corrected. Added reference
JHEP 0206 (2002) 018
10.1088/1126-6708/2002/06/018
null
hep-ph
null
In the usual factorization theorems, which give predictions only for inclusive cross sections, there is considerable freedom in the choice of the scheme to define the parton distribution functions. These theorems do not directly apply to Monte-Carlo event generators, and more general factorization theorems which give predictions for fully exclusive cross sections are needed. It has been shown that appropriate parton distribution functions are uniquely defined by the showering algorithm. In this paper, we present results of calculations of the Monte-Carlo parton distribution functions in terms of the commonly used MSbar parton distribution functions. At small x the differences are large, which demonstrates the importance of using the correct parton distribution functions in an event generator rather than MSbar parton distribution functions. We present some simple approximations that enable an understanding of the sizes of the results to be obtained.
[ { "created": "Thu, 11 Apr 2002 15:57:05 GMT", "version": "v1" }, { "created": "Sun, 14 Apr 2002 20:39:01 GMT", "version": "v2" }, { "created": "Mon, 3 Jun 2002 19:58:34 GMT", "version": "v3" }, { "created": "Thu, 13 Jun 2002 13:29:43 GMT", "version": "v4" } ]
2009-11-07
[ [ "Collins", "John C.", "" ], [ "Zu", "Xiaomin", "" ] ]
In the usual factorization theorems, which give predictions only for inclusive cross sections, there is considerable freedom in the choice of the scheme to define the parton distribution functions. These theorems do not directly apply to Monte-Carlo event generators, and more general factorization theorems which give predictions for fully exclusive cross sections are needed. It has been shown that appropriate parton distribution functions are uniquely defined by the showering algorithm. In this paper, we present results of calculations of the Monte-Carlo parton distribution functions in terms of the commonly used MSbar parton distribution functions. At small x the differences are large, which demonstrates the importance of using the correct parton distribution functions in an event generator rather than MSbar parton distribution functions. We present some simple approximations that enable an understanding of the sizes of the results to be obtained.
2111.10879
Holger Frits Bech Nielsen
C. D. Froggatt (Glasgow University), H.B.Nielsen (Niels Bohr Institute)
Atomic Size Dark Matter Pearls, Electron Signal
Proceeding contribution to the 24th Workshop "What Comes Beyond the Standard Models'', Bled, July 3.-- 11., 2021 H.B. Nielsen gave the talk
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explain both the observation of dark matter by the seasonal variation of the DAMA-LIBRA data and the observation of ``electron recoil'' events at Xenon1T by the SAME dark matter model. This DM is bubbles of a new type of vacuum containing ordinary atomic matter under high pressure ensured by the surface tension of the domain wall. Surrounding it a cloud of electrons almost of atomic size. Also we explain the self interactions of dark matter suggested by astronomical studies of dwarf galaxies etc. Interaction in the shielding slows the dark matter down to a low terminal velocity. Nuclei in the underground detectors are thus not detected. Further we explain the ``mysterious'' X-ray line of 3.5 keV from our dark matter particles colliding with each other so that the surfaces/skins unite. Even the 3.5 keV X-ray radiation from the Tycho supernova remnant is explained as our pearls hitting cosmic rays in the remnant. DAMA-LIBRA and Xenon1T experiments see supposedly our dark matter pearls excited during their stopping in the shielding or the air. The most remarkable support for our type of model is that both these underground experiments see events with about 3.5 keV energy, just the energy of the X-ray line. We get a good numerical understanding of the fitted cross section over mass ratio of self interacting dark matter observed in the study of dwarf galaxies. Also the total energy of the dark matter pearls stopped in the shield is reasonably matching order of magnitudewise with the absolute observation rates of DAMA-LIBRA and Xenon1T, although the their ratio requires further development. Accepting that the different phases of the vacuum could be realized inside the Standard Model, our whole scheme also could. No new physics is needed for dark matter!
[ { "created": "Sun, 21 Nov 2021 19:11:12 GMT", "version": "v1" } ]
2021-11-23
[ [ "Froggatt", "C. D.", "", "Glasgow University" ], [ "Nielsen", "H. B.", "", "Niels Bohr\n Institute" ] ]
We explain both the observation of dark matter by the seasonal variation of the DAMA-LIBRA data and the observation of ``electron recoil'' events at Xenon1T by the SAME dark matter model. This DM is bubbles of a new type of vacuum containing ordinary atomic matter under high pressure ensured by the surface tension of the domain wall. Surrounding it a cloud of electrons almost of atomic size. Also we explain the self interactions of dark matter suggested by astronomical studies of dwarf galaxies etc. Interaction in the shielding slows the dark matter down to a low terminal velocity. Nuclei in the underground detectors are thus not detected. Further we explain the ``mysterious'' X-ray line of 3.5 keV from our dark matter particles colliding with each other so that the surfaces/skins unite. Even the 3.5 keV X-ray radiation from the Tycho supernova remnant is explained as our pearls hitting cosmic rays in the remnant. DAMA-LIBRA and Xenon1T experiments see supposedly our dark matter pearls excited during their stopping in the shielding or the air. The most remarkable support for our type of model is that both these underground experiments see events with about 3.5 keV energy, just the energy of the X-ray line. We get a good numerical understanding of the fitted cross section over mass ratio of self interacting dark matter observed in the study of dwarf galaxies. Also the total energy of the dark matter pearls stopped in the shield is reasonably matching order of magnitudewise with the absolute observation rates of DAMA-LIBRA and Xenon1T, although the their ratio requires further development. Accepting that the different phases of the vacuum could be realized inside the Standard Model, our whole scheme also could. No new physics is needed for dark matter!
1801.03059
Pankaj Saha
Debaprasad Maity and Pankaj Saha
Connecting CMB anisotropy and cold dark matter phenomenology via reheating
Added discussions, matches published version
Phys. Rev. D 98, 103525 (2018)
10.1103/PhysRevD.98.103525
null
hep-ph gr-qc
http://creativecommons.org/licenses/by/4.0/
Understanding the properties of dark matter has proved to be one of the most challenging problems of particle phenomenology. In this paper, we have tried to understand the phenomenology of dark matter in light of very well understood properties of cosmic microwave background (CMB) anisotropy. To connect these two, inflation and its subsequent evolution known as the reheating phase play the important role. Following the previous analysis, we first established a one-to-one correspondence between the CMB power spectrum and the reheating temperature assuming the perturbative reheating scenario. Further by incorporating a possible dark matter candidate through the radiation annihilation process during reheating and the current value of dark matter abundance, we constrain the dark matter parameter space through the inflationary power spectrum for different inflationary models.
[ { "created": "Tue, 9 Jan 2018 17:51:34 GMT", "version": "v1" }, { "created": "Tue, 27 Feb 2018 13:36:08 GMT", "version": "v2" }, { "created": "Tue, 27 Nov 2018 17:51:33 GMT", "version": "v3" } ]
2018-11-28
[ [ "Maity", "Debaprasad", "" ], [ "Saha", "Pankaj", "" ] ]
Understanding the properties of dark matter has proved to be one of the most challenging problems of particle phenomenology. In this paper, we have tried to understand the phenomenology of dark matter in light of very well understood properties of cosmic microwave background (CMB) anisotropy. To connect these two, inflation and its subsequent evolution known as the reheating phase play the important role. Following the previous analysis, we first established a one-to-one correspondence between the CMB power spectrum and the reheating temperature assuming the perturbative reheating scenario. Further by incorporating a possible dark matter candidate through the radiation annihilation process during reheating and the current value of dark matter abundance, we constrain the dark matter parameter space through the inflationary power spectrum for different inflationary models.
hep-ph/0304293
Toshifumi Yamashita
Nobuhiro Maekawa and Toshifumi Yamashita
Flipped SO(10) model
12 pages, examples are corrected
Phys.Lett. B567 (2003) 330-338
10.1016/j.physletb.2003.06.054
KUNS-1840
hep-ph
null
We show that as in the flipped SU(5) models, doublet-triplet splitting is realized by the missing partner mechanism in the flipped SO(10) models. The gauge group $SO(10)_F\times U(1)_{V'_F}$ includes $SU(2)_E$ gauge symmetry, that plays an important role in solving supersymmetric flavor problem by introducing non-abelian horizontal gauge symmetry and anomalous $U(1)_A$ gauge symmetry. The gauge group can be broken into the standard model gauge group by VEVs of only spinor fields, such models may be easier than $E_6$ models to be derived from the superstring theory.
[ { "created": "Wed, 30 Apr 2003 15:02:57 GMT", "version": "v1" }, { "created": "Tue, 6 May 2003 14:46:43 GMT", "version": "v2" } ]
2009-11-10
[ [ "Maekawa", "Nobuhiro", "" ], [ "Yamashita", "Toshifumi", "" ] ]
We show that as in the flipped SU(5) models, doublet-triplet splitting is realized by the missing partner mechanism in the flipped SO(10) models. The gauge group $SO(10)_F\times U(1)_{V'_F}$ includes $SU(2)_E$ gauge symmetry, that plays an important role in solving supersymmetric flavor problem by introducing non-abelian horizontal gauge symmetry and anomalous $U(1)_A$ gauge symmetry. The gauge group can be broken into the standard model gauge group by VEVs of only spinor fields, such models may be easier than $E_6$ models to be derived from the superstring theory.
2202.00996
Daniel Locke
Alexander Belyaev, Giacomo Cacciapaglia, Daniel Locke
Minimal Consistent models for systematic Dark Matter exploration
10 pages, 3 figures, contribution to 55th Rencontres de Moriond on QCD and High Energy Interactions (Moriond QCD 2021)(C21-03-27), March 27-April 3, 2021
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dark Matter searches in collider and non-collider experiments requires systematic and consistent approach. We suggest and perform classification of Minimal Consistent Dark Matter models which are aimed to create a solid framework for Dark Matter exploration.
[ { "created": "Wed, 2 Feb 2022 12:30:56 GMT", "version": "v1" }, { "created": "Thu, 3 Feb 2022 09:45:06 GMT", "version": "v2" } ]
2022-02-04
[ [ "Belyaev", "Alexander", "" ], [ "Cacciapaglia", "Giacomo", "" ], [ "Locke", "Daniel", "" ] ]
Dark Matter searches in collider and non-collider experiments requires systematic and consistent approach. We suggest and perform classification of Minimal Consistent Dark Matter models which are aimed to create a solid framework for Dark Matter exploration.
hep-ph/0512076
Peihong Gu
Pei-Hong Gu, Xiao-Jun Bi, Bo Feng, Bing-Lin Young, and Xinmin Zhang
Detecting dark energy in long baseline neutrino oscillations
9 pages, 6 figures
Chin.Phys.C32:530-535,2008
10.1088/1674-1137/32/7/004
BIHEP-TH-2005-16, RESCEU-38/05
hep-ph
null
In this paper, we discuss a possibility of studying properties of dark energy in long baseline neutrino oscillation experiments. We consider two types of models of neutrino dark energy. For one type of models the scalar field is taken to be quintessence-like and for the other phantom-like. In these models the scalar fields couple to the neutrinos to give rise to a spatially varying neutrino masses. We will show that the two types of models predict different behaviors of the spatial variation of the neutrino masses inside Earth and consequently result in different signals in long baseline neutrino oscillation experiments.
[ { "created": "Tue, 6 Dec 2005 14:48:01 GMT", "version": "v1" } ]
2011-08-31
[ [ "Gu", "Pei-Hong", "" ], [ "Bi", "Xiao-Jun", "" ], [ "Feng", "Bo", "" ], [ "Young", "Bing-Lin", "" ], [ "Zhang", "Xinmin", "" ] ]
In this paper, we discuss a possibility of studying properties of dark energy in long baseline neutrino oscillation experiments. We consider two types of models of neutrino dark energy. For one type of models the scalar field is taken to be quintessence-like and for the other phantom-like. In these models the scalar fields couple to the neutrinos to give rise to a spatially varying neutrino masses. We will show that the two types of models predict different behaviors of the spatial variation of the neutrino masses inside Earth and consequently result in different signals in long baseline neutrino oscillation experiments.
hep-ph/9808259
Uma Mahanta
Uma Mahanta
Probing the SUSY breaking scale at an $e^-e^-$ collider
Plain Tex, 7 pages, No figures
Phys.Rev. D59 (1999) 035006
10.1103/PhysRevD.59.035006
MRI-PHY/980812
hep-ph
null
If supersymmetry is spontaneously at a low energy scale then the resulting gravitino would be very light. The interaction strength of the longitudinal components of such a light gravitino to electron-selectron pair then becomes comparable to that of electroweak interactions. Such a light gravitino could modify the cross-section for $e^_L e^_R-->\tilde {e}_L\tilde {e}_R$ from its MSSM value. Precision measurement of this cross-section could therefore be used to probe the low energy SUSY breaking scale.
[ { "created": "Fri, 7 Aug 1998 12:20:22 GMT", "version": "v1" } ]
2009-10-31
[ [ "Mahanta", "Uma", "" ] ]
If supersymmetry is spontaneously at a low energy scale then the resulting gravitino would be very light. The interaction strength of the longitudinal components of such a light gravitino to electron-selectron pair then becomes comparable to that of electroweak interactions. Such a light gravitino could modify the cross-section for $e^_L e^_R-->\tilde {e}_L\tilde {e}_R$ from its MSSM value. Precision measurement of this cross-section could therefore be used to probe the low energy SUSY breaking scale.
0806.2531
Alexander Manashov
V.M. Braun, A.N. Manashov and J. Rohrwild
Baryon Operators of Higher Twist in QCD and Nucleon Distribution Amplitudes
60 pages, 6 figures, pdflatex, typos corrected
Nucl.Phys.B807:89-137,2009
10.1016/j.nuclphysb.2008.08.012
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We develop a general theoretical framework for the description of higher-twist baryon operators which makes maximal use of the conformal symmetry of the QCD Lagrangian. The conformal operator basis is constructed for all twists. The complete analysis of the one-loop renormalization of twist-4 operators is given. The evolution equation for three-quark operators of the same chirality turns out to be completely integrable. The spectrum of anomalous dimensions coincides in this case with the energy spectrum of the twist-4 subsector of the SU(2,2) Heisenberg spin chain. The results are applied to give a general classification and calculate the scale dependence of subleading twist-4 nucleon distribution amplitudes that are relevant for hard exclusive reactions involving a helicity flip. In particular we find an all-order expression (in conformal spin) for the contributions of geometric twist-3 operators to the (light-cone) twist-4 nucleon distribution amplitudes, which are usually referred to as Wandzura-Wilczek terms.
[ { "created": "Mon, 16 Jun 2008 10:56:11 GMT", "version": "v1" }, { "created": "Tue, 11 Aug 2009 16:37:51 GMT", "version": "v2" } ]
2009-08-11
[ [ "Braun", "V. M.", "" ], [ "Manashov", "A. N.", "" ], [ "Rohrwild", "J.", "" ] ]
We develop a general theoretical framework for the description of higher-twist baryon operators which makes maximal use of the conformal symmetry of the QCD Lagrangian. The conformal operator basis is constructed for all twists. The complete analysis of the one-loop renormalization of twist-4 operators is given. The evolution equation for three-quark operators of the same chirality turns out to be completely integrable. The spectrum of anomalous dimensions coincides in this case with the energy spectrum of the twist-4 subsector of the SU(2,2) Heisenberg spin chain. The results are applied to give a general classification and calculate the scale dependence of subleading twist-4 nucleon distribution amplitudes that are relevant for hard exclusive reactions involving a helicity flip. In particular we find an all-order expression (in conformal spin) for the contributions of geometric twist-3 operators to the (light-cone) twist-4 nucleon distribution amplitudes, which are usually referred to as Wandzura-Wilczek terms.
1709.09596
German F. R. Sborlini
German F. R. Sborlini
Higher-order QED effects in hadronic processes
7 pages, 2 figures. Contribution to the Proceedings of the EPS-HEP 2017 Conference
PoS(EPS-HEP2017)398
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this presentation, we describe the computation of higher-order QED effects relevant in hadronic collisions. In particular, we discuss the calculation of mixed QCD-QED one-loop contributions to the Altarelli-Parisi splittings functions, as well as the pure two-loop QED corrections. We explain how to extend the DGLAP equations to deal with new parton distributions, emphasizing the consequences of the novel corrections in the determination (and evolution) of the photon distributions.
[ { "created": "Wed, 27 Sep 2017 15:56:57 GMT", "version": "v1" } ]
2017-09-28
[ [ "Sborlini", "German F. R.", "" ] ]
In this presentation, we describe the computation of higher-order QED effects relevant in hadronic collisions. In particular, we discuss the calculation of mixed QCD-QED one-loop contributions to the Altarelli-Parisi splittings functions, as well as the pure two-loop QED corrections. We explain how to extend the DGLAP equations to deal with new parton distributions, emphasizing the consequences of the novel corrections in the determination (and evolution) of the photon distributions.
0810.3142
Defu Hou
Bo Feng, Defu Hou, and Hai-cang Ren
Angular Momentum Mixing in Single Flavor Color Superconductivity with Transverse Pairing
16 pages, 2 figures, 1 table in Revtex
Nucl.Phys.B813:408-429,2009
10.1016/j.nuclphysb.2008.12.020
RU06-9-B
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Because of the equal strength of the pairing potential mediated by one-gluon exchange for all partial waves to the leading order QCD running coupling constant and the nonlinearity of the gap equation, the non-spherical pairing in single flavor color superconductivity(CSC) can not be restricted in a single non-s-wave channel and the mixing among different angular momenta will occur. In this paper, we examine the angular momentum mixing in single flavor CSC with transverse pairing, in which the pairing quarks have opposite helicity. We find that the free energy of all non-spherical pairing states are lowered by angular momentum mixing compared with that contain p-wave only. But the amount of the free energy drop is numerically small. Consequently the most stable pairing state that respect the time reversal invariance remains the spherical CSL.
[ { "created": "Fri, 17 Oct 2008 12:29:15 GMT", "version": "v1" } ]
2014-11-18
[ [ "Feng", "Bo", "" ], [ "Hou", "Defu", "" ], [ "Ren", "Hai-cang", "" ] ]
Because of the equal strength of the pairing potential mediated by one-gluon exchange for all partial waves to the leading order QCD running coupling constant and the nonlinearity of the gap equation, the non-spherical pairing in single flavor color superconductivity(CSC) can not be restricted in a single non-s-wave channel and the mixing among different angular momenta will occur. In this paper, we examine the angular momentum mixing in single flavor CSC with transverse pairing, in which the pairing quarks have opposite helicity. We find that the free energy of all non-spherical pairing states are lowered by angular momentum mixing compared with that contain p-wave only. But the amount of the free energy drop is numerically small. Consequently the most stable pairing state that respect the time reversal invariance remains the spherical CSL.
1005.1998
Shuji Sasagawa
Shuji Sasagawa and Hidekazu Tanaka
Numerical Calculation of Schwinger-Dyson Equation with Momentum-Dependent Gauge Parameter at Finite Temperature
15 page, 12 figures
Prog.Theor.Phys.123:533-545, 2010
10.1143/PTP.123.533
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Chiral symmetry at finite temperature is studied using the Schwinger-Dyson equation. We calculate numerically the critical temperature using the Schwinger-Dyson equation with the gauge parameter that depends on an external momentum. The critical temperature obtained by this method is similar to that with the Landau gauge and wave function renormalization constant 1. Moreover, the gauge invariance in the ladder approximation is examined using our method.
[ { "created": "Wed, 12 May 2010 06:51:00 GMT", "version": "v1" }, { "created": "Sun, 27 Jun 2010 12:13:24 GMT", "version": "v2" } ]
2015-03-17
[ [ "Sasagawa", "Shuji", "" ], [ "Tanaka", "Hidekazu", "" ] ]
Chiral symmetry at finite temperature is studied using the Schwinger-Dyson equation. We calculate numerically the critical temperature using the Schwinger-Dyson equation with the gauge parameter that depends on an external momentum. The critical temperature obtained by this method is similar to that with the Landau gauge and wave function renormalization constant 1. Moreover, the gauge invariance in the ladder approximation is examined using our method.
2404.15984
Christian G\"utschow
Christian Bierlich, Andy Buckley, Jonathan Butterworth, Christian Gutschow, Leif Lonnblad, Tomasz Procter, Peter Richardson, Yoran Yeh
Robust Independent Validation of Experiment and Theory: Rivet version 4 release note
null
null
null
MCNET-24-05
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
The Rivet toolkit is the primary mechanism for phenomenological preservation of collider-physics measurements, containing both a computational core and API for analysis implementation, and a large collection of more than a thousand preserved analyses. In this note we summarise the main changes in the new Rivet 4 major release series. These include a major generalisation and more semantically coherent model for histograms and related data objects, a thorough clean-up of inelegant and legacy observable-computation tools, and new systems for extended analysis-data, incorporation of preserved machine-learning models, and serialization for high-performance computing applications. Where these changes introduce backward-incompatible interface changes, existing analyses have been updated and indications are given on how to update new analysis routines and workflows.
[ { "created": "Wed, 24 Apr 2024 17:00:24 GMT", "version": "v1" }, { "created": "Mon, 13 May 2024 08:09:41 GMT", "version": "v2" }, { "created": "Tue, 13 Aug 2024 08:28:56 GMT", "version": "v3" } ]
2024-08-14
[ [ "Bierlich", "Christian", "" ], [ "Buckley", "Andy", "" ], [ "Butterworth", "Jonathan", "" ], [ "Gutschow", "Christian", "" ], [ "Lonnblad", "Leif", "" ], [ "Procter", "Tomasz", "" ], [ "Richardson", "Peter", ...
The Rivet toolkit is the primary mechanism for phenomenological preservation of collider-physics measurements, containing both a computational core and API for analysis implementation, and a large collection of more than a thousand preserved analyses. In this note we summarise the main changes in the new Rivet 4 major release series. These include a major generalisation and more semantically coherent model for histograms and related data objects, a thorough clean-up of inelegant and legacy observable-computation tools, and new systems for extended analysis-data, incorporation of preserved machine-learning models, and serialization for high-performance computing applications. Where these changes introduce backward-incompatible interface changes, existing analyses have been updated and indications are given on how to update new analysis routines and workflows.
0704.2588
Wai-Yee Keung
Kingman Cheung, Wai-Yee Keung, and Tzu-Chiang Yuan
Collider signals in unparticle physics
4 pages including 4 figures
Phys.Rev.Lett.99:051803,2007
10.1103/PhysRevLett.99.051803
null
hep-ph
null
Phenomenology of the notion of an unparticle U, recently perceived by Georgi, to describe a scale invariant sector with a non-trivial infrared fixed point at a higher energy scale is explored in details. Behaving like a collection of d_U (the scale dimension of the unparticle operator O_U) invisible massless particles, this unparticle can be unveiled by measurements of various energy distributions for the processes Z to fermion pair + U and e-e+ to gamma U at e-e+ colliders, as well as mono-jet production at hadron colliders. We also study the propagator effects of the unparticle through the Drell-Yan tree level process and the one-loop muon anomaly.
[ { "created": "Thu, 19 Apr 2007 19:51:52 GMT", "version": "v1" }, { "created": "Wed, 25 Apr 2007 19:35:51 GMT", "version": "v2" }, { "created": "Thu, 9 Aug 2007 20:02:37 GMT", "version": "v3" } ]
2008-11-26
[ [ "Cheung", "Kingman", "" ], [ "Keung", "Wai-Yee", "" ], [ "Yuan", "Tzu-Chiang", "" ] ]
Phenomenology of the notion of an unparticle U, recently perceived by Georgi, to describe a scale invariant sector with a non-trivial infrared fixed point at a higher energy scale is explored in details. Behaving like a collection of d_U (the scale dimension of the unparticle operator O_U) invisible massless particles, this unparticle can be unveiled by measurements of various energy distributions for the processes Z to fermion pair + U and e-e+ to gamma U at e-e+ colliders, as well as mono-jet production at hadron colliders. We also study the propagator effects of the unparticle through the Drell-Yan tree level process and the one-loop muon anomaly.
hep-ph/0305328
Wolfgang Hollik
W. Hollik, H. Rzehak
The sfermion mass spectrum of the MSSM at the one-loop level
13 pages, 3 figures, version to appear in Eur. Phys. J. C
Eur.Phys.J. C32 (2003) 127-133
10.1140/epjc/s2003-01387-9
null
hep-ph
null
The sfermion-mass spectrum of the minimal supersymmetric standard model is investigated at the one-loop level. An on-shell scheme has been specified for renormalization of the basic breaking parameters of the sfermionic sector. Owing to SU(2)-invariance, the soft-breaking mass parameters of the left-chiral scalar fermions of each isospin doublet are identical. Thus, one of the sfermion-masses of each doublet can be expressed in terms of the other masses and receives a mass shift at the one-loop level with respect to the lowest-order value, which can be of $O(10$ GeV). Both strong and electroweak contributions have been calculated for scalar quarks and leptons.
[ { "created": "Fri, 30 May 2003 09:50:25 GMT", "version": "v1" }, { "created": "Wed, 12 Nov 2003 17:18:56 GMT", "version": "v2" } ]
2009-11-10
[ [ "Hollik", "W.", "" ], [ "Rzehak", "H.", "" ] ]
The sfermion-mass spectrum of the minimal supersymmetric standard model is investigated at the one-loop level. An on-shell scheme has been specified for renormalization of the basic breaking parameters of the sfermionic sector. Owing to SU(2)-invariance, the soft-breaking mass parameters of the left-chiral scalar fermions of each isospin doublet are identical. Thus, one of the sfermion-masses of each doublet can be expressed in terms of the other masses and receives a mass shift at the one-loop level with respect to the lowest-order value, which can be of $O(10$ GeV). Both strong and electroweak contributions have been calculated for scalar quarks and leptons.
1508.07402
Robert Foot
R. Foot
Can dark matter - electron scattering explain the DAMA annual modulation consistent with XENON100 constraints?
This paper used an oversimplified description of a complex problem which is unlikely to be very useful. A better description is given in 1512.06471, which supersedes this paper
null
null
null
hep-ph astro-ph.GA
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For many years annually modulating $\sim$ keV scintillations have been observed in the DAMA/NaI and DAMA/Libra experiments. A dark matter - electron scattering interpretation is now favoured given the stringent constraints on nuclear recoil rates obtained by LUX, SuperCDMS and other experiments. Very recently, the XENON100 experiment has observed a modest annual modulation in their electron recoil events (2.8 $\sigma$ C.L.) with phase consistent with that of the DAMA experiments. However, they also found a stringent upper limit on the unmodulated rate, which suggests that any dark matter - electron scattering interpretation of these annual modulations must involve a large modulation fraction $\stackrel{>}{\sim} 50\%$. Here we discuss the extent to which these results might be able to be accommodated within multi-component dark matter models featuring light dark matter particles of mass $\sim$ MeV, focusing on the mirror dark matter case for definiteness. The importance of diurnal variation as a means of testing these kinds of models is also discussed.
[ { "created": "Sat, 29 Aug 2015 05:37:40 GMT", "version": "v1" }, { "created": "Thu, 1 Oct 2015 03:14:40 GMT", "version": "v2" }, { "created": "Wed, 29 Jun 2016 22:42:05 GMT", "version": "v3" } ]
2016-07-01
[ [ "Foot", "R.", "" ] ]
For many years annually modulating $\sim$ keV scintillations have been observed in the DAMA/NaI and DAMA/Libra experiments. A dark matter - electron scattering interpretation is now favoured given the stringent constraints on nuclear recoil rates obtained by LUX, SuperCDMS and other experiments. Very recently, the XENON100 experiment has observed a modest annual modulation in their electron recoil events (2.8 $\sigma$ C.L.) with phase consistent with that of the DAMA experiments. However, they also found a stringent upper limit on the unmodulated rate, which suggests that any dark matter - electron scattering interpretation of these annual modulations must involve a large modulation fraction $\stackrel{>}{\sim} 50\%$. Here we discuss the extent to which these results might be able to be accommodated within multi-component dark matter models featuring light dark matter particles of mass $\sim$ MeV, focusing on the mirror dark matter case for definiteness. The importance of diurnal variation as a means of testing these kinds of models is also discussed.
hep-ph/9712211
null
V. A. Maisheev
Gamma-quanta propagation in single crystals
6 pages, 6 eps figures, Latex, epsfig.sty, typos corrected
null
null
null
hep-ph physics.ins-det
null
Propagation of gamma-quanta in the single crystals, oriented in a region of the coherent pair production is considered. The qualitative description of the process is also discussed. The theory of gamma-quanta propagation in the anisotropic medium is illustrated by the help of the particular calculations of such a process in silicon single crystals. It is shown that the single crystals are sensitive to the initial circular polarization of gamma-beam despite the fact that the cross section of absorption is independent of it. The reason is that the normal electromagnetic waves (an eigenfunctions of the problem) are elliptically polarized. The speeds of absorption and motion of both the normal waves are different and as a result the process of gamma-quanta propagation depend on the initial polarization state. The calculated value of asymmetry is about 20% for 25 GeV gamma-quanta propagating in 100 cm silicon single crystal. The obtained results are useful in creating of polarimeters for high energy electrons and gamma-quanta.
[ { "created": "Mon, 1 Dec 1997 07:29:36 GMT", "version": "v1" }, { "created": "Fri, 5 Dec 1997 07:31:06 GMT", "version": "v2" } ]
2016-09-06
[ [ "Maisheev", "V. A.", "" ] ]
Propagation of gamma-quanta in the single crystals, oriented in a region of the coherent pair production is considered. The qualitative description of the process is also discussed. The theory of gamma-quanta propagation in the anisotropic medium is illustrated by the help of the particular calculations of such a process in silicon single crystals. It is shown that the single crystals are sensitive to the initial circular polarization of gamma-beam despite the fact that the cross section of absorption is independent of it. The reason is that the normal electromagnetic waves (an eigenfunctions of the problem) are elliptically polarized. The speeds of absorption and motion of both the normal waves are different and as a result the process of gamma-quanta propagation depend on the initial polarization state. The calculated value of asymmetry is about 20% for 25 GeV gamma-quanta propagating in 100 cm silicon single crystal. The obtained results are useful in creating of polarimeters for high energy electrons and gamma-quanta.
1711.05495
Pablo G. Ortega
Pablo G. Ortega, Jorge Segovia, David R. Entem, Francisco Fern\'andez
Threshold effects in hadron spectrum: a new spectroscopy?
Proceedings of 6th International Conference on New Frontiers in Physics (ICNFP 2017). 10 pages, 1 figure, 8 tables
null
10.1051/epjconf/201818202094
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The exploration of energies above the open-flavor threshold in the meson spectra has led to the appearance of unexpected states difficult to accommodate in the naive picture of a bound state of a quark and an antiquark. Many of such states are located close to meson-meson thresholds, which suggests that molecular structures may be a relevant component in the total wave function of such resonances. In this work, the state of meson-meson molecules calculations is reviewed, using a non-relativistic constituent quark model that has been applied to a wide range of hadronic observables, and therefore all model parameters are completely constrained. The model has been able to reproduce, among others, the properties of the X(3872), described as a mixture of $c\bar c$ and $D\bar D^\ast$ states, or the spectrum of the P-wave charm-strange mesons, which are well reproduced only if $DK$ and $D^\ast K$ structures are taken into account. We show that such constituent quark model, which is able to describe the ordinary heavy meson spectra, is also capable of providing a good description of many new states recently reported.
[ { "created": "Wed, 15 Nov 2017 10:53:17 GMT", "version": "v1" } ]
2018-08-29
[ [ "Ortega", "Pablo G.", "" ], [ "Segovia", "Jorge", "" ], [ "Entem", "David R.", "" ], [ "Fernández", "Francisco", "" ] ]
The exploration of energies above the open-flavor threshold in the meson spectra has led to the appearance of unexpected states difficult to accommodate in the naive picture of a bound state of a quark and an antiquark. Many of such states are located close to meson-meson thresholds, which suggests that molecular structures may be a relevant component in the total wave function of such resonances. In this work, the state of meson-meson molecules calculations is reviewed, using a non-relativistic constituent quark model that has been applied to a wide range of hadronic observables, and therefore all model parameters are completely constrained. The model has been able to reproduce, among others, the properties of the X(3872), described as a mixture of $c\bar c$ and $D\bar D^\ast$ states, or the spectrum of the P-wave charm-strange mesons, which are well reproduced only if $DK$ and $D^\ast K$ structures are taken into account. We show that such constituent quark model, which is able to describe the ordinary heavy meson spectra, is also capable of providing a good description of many new states recently reported.
1306.1911
David London
Bhubanjyoti Bhattacharya, Alakabha Datta, Murugeswaran Duraisamy and David London
Searching for New Physics with bbar -> sbar Bs -> V_1 V_2 Penguin Decays
21 pages, no figures. Reference added
null
10.1103/PhysRevD.88.016007
UMISS-HEP-2013-06, UdeM-GPP-TH-13-224
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the most general (six-helicity) angular analysis of Bs -> V_1 (-> P_1P'_1) V_2 (-> P_2P'_2) (V_i is a vector meson, and P_i, P'_i are pseudoscalars). We focus on final states accessible to both Bs and Bsbar -- these are mainly bbar -> sbar penguin decays. We also derive the most general decay amplitude, and discuss the differences between it and that used by LHCb in its analysis of Bs -> phi phi. In the standard model, all CP violation is predicted to be small, so that the simple measurement of a sizeable CP-violating observable indicates the presence of new physics. A full fit to the data is not necessary. By determining which of the CP-violating observables are nonzero, one can learn about the structure of the underlying NP. Finally, we apply the angular analysis to Bs -> K^{*0} Kbar^{*0}, and show that there are numerous CP-violating observables that remain in the untagged data sample.
[ { "created": "Sat, 8 Jun 2013 12:18:19 GMT", "version": "v1" }, { "created": "Sun, 16 Jun 2013 14:21:34 GMT", "version": "v2" } ]
2013-08-09
[ [ "Bhattacharya", "Bhubanjyoti", "" ], [ "Datta", "Alakabha", "" ], [ "Duraisamy", "Murugeswaran", "" ], [ "London", "David", "" ] ]
We present the most general (six-helicity) angular analysis of Bs -> V_1 (-> P_1P'_1) V_2 (-> P_2P'_2) (V_i is a vector meson, and P_i, P'_i are pseudoscalars). We focus on final states accessible to both Bs and Bsbar -- these are mainly bbar -> sbar penguin decays. We also derive the most general decay amplitude, and discuss the differences between it and that used by LHCb in its analysis of Bs -> phi phi. In the standard model, all CP violation is predicted to be small, so that the simple measurement of a sizeable CP-violating observable indicates the presence of new physics. A full fit to the data is not necessary. By determining which of the CP-violating observables are nonzero, one can learn about the structure of the underlying NP. Finally, we apply the angular analysis to Bs -> K^{*0} Kbar^{*0}, and show that there are numerous CP-violating observables that remain in the untagged data sample.
1606.00946
S. Ganesh
S. Ganesh, M. Mishra
Effect of temperature gradient on heavy quark anti-quark potential using gravity dual model
17 pages, 7 figures. Accepted in PTEP (Progress of Theoretical and Experimental Physics)
Prog Theor Exp Phys (2020)
10.1093/ptep/ptaa180
null
hep-ph gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Thermal systems have traditionally been modeled via Euclideanized space by analytical continuation of time to an imaginary time. We extend the concept to static thermal gradients by recasting the temperature variation as a variation in the Euclidean metric. We apply this prescription to determine the Quark anti-Quark potential in a system with thermal gradient. A naturally occurring QCD medium with thermal gradients is a Quark Gluon Plasma (QGP). However, the QGP evolves in time. Hence, we use a quasi-stationary approximation, which is applicable only if the rate of time evolution is slow. The application of our proposal to a Quark anti-Quark potential in QGP can be seen as a step towards a more exact theory which would incorporate time varying thermal gradients. The effect of a static temperature gradient on the Quark anti-Quark potential is analyzed using a gravity dual model. A non-uniform black string metric is developed, by perturbing the Schwarzchild metric, which allows to incorporate the temperature gradient in the dual AdS space. Finally, an expression for the Quark anti-Quark potential, in the presence of a static temperature gradient, is derived.
[ { "created": "Fri, 3 Jun 2016 01:54:05 GMT", "version": "v1" }, { "created": "Mon, 13 Nov 2017 14:06:09 GMT", "version": "v2" }, { "created": "Fri, 3 Apr 2020 10:52:21 GMT", "version": "v3" }, { "created": "Sat, 12 Dec 2020 06:15:53 GMT", "version": "v4" } ]
2021-02-10
[ [ "Ganesh", "S.", "" ], [ "Mishra", "M.", "" ] ]
Thermal systems have traditionally been modeled via Euclideanized space by analytical continuation of time to an imaginary time. We extend the concept to static thermal gradients by recasting the temperature variation as a variation in the Euclidean metric. We apply this prescription to determine the Quark anti-Quark potential in a system with thermal gradient. A naturally occurring QCD medium with thermal gradients is a Quark Gluon Plasma (QGP). However, the QGP evolves in time. Hence, we use a quasi-stationary approximation, which is applicable only if the rate of time evolution is slow. The application of our proposal to a Quark anti-Quark potential in QGP can be seen as a step towards a more exact theory which would incorporate time varying thermal gradients. The effect of a static temperature gradient on the Quark anti-Quark potential is analyzed using a gravity dual model. A non-uniform black string metric is developed, by perturbing the Schwarzchild metric, which allows to incorporate the temperature gradient in the dual AdS space. Finally, an expression for the Quark anti-Quark potential, in the presence of a static temperature gradient, is derived.
1103.2025
Peng Sun
Cong-Feng Qiao and Peng Sun and Feng Yuan
NLO QCD Corrections to $B_c$-to-Charmonium Form Factors
null
null
10.1007/JHEP08(2012)087
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $B_c(^1S_0)$ meson to S-wave Charmonia transition form factors are calculated in next-to-leading order(NLO) accuracy of Quantum Chromodynamics(QCD). Our results indicate that the higher order corrections to these form factors are remarkable, and hence are important to the phenomenological study of the corresponding processes. For the convenience of comparison and use, the relevant expressions in asymptotic form at the limit of $m_c\rightarrow0$ for the radiative corrections are presented.
[ { "created": "Thu, 10 Mar 2011 13:10:57 GMT", "version": "v1" }, { "created": "Mon, 13 Jun 2011 12:48:20 GMT", "version": "v2" }, { "created": "Sun, 15 Apr 2012 05:18:57 GMT", "version": "v3" } ]
2015-05-27
[ [ "Qiao", "Cong-Feng", "" ], [ "Sun", "Peng", "" ], [ "Yuan", "Feng", "" ] ]
The $B_c(^1S_0)$ meson to S-wave Charmonia transition form factors are calculated in next-to-leading order(NLO) accuracy of Quantum Chromodynamics(QCD). Our results indicate that the higher order corrections to these form factors are remarkable, and hence are important to the phenomenological study of the corresponding processes. For the convenience of comparison and use, the relevant expressions in asymptotic form at the limit of $m_c\rightarrow0$ for the radiative corrections are presented.
2301.07443
Di Wang
Jin-Feng Luo, Di Wang
Isospin sum rules in charmed baryon weak decays
47 pages. arXiv admin note: text overlap with arXiv:2301.06104
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Isospin symmetry is the most precise flavor symmetry. The effective Hamiltonian of charm quark weak decay is zero under the isospin lowering operators $I_-^n$, which permits us to generate isospin sum rules through several master formulas. In this work, we derive the master formulas of isospin sum rules for the two- and three-body non-leptonic decays of singly and doubly charmed baryons. Hundreds of isospin sum rules are derived to test of isospin symmetry and provide hints for the new decay modes. The isospin sum rules for multi-body decays are not broken by the intermediate resonances and hence can be used to study the isospin partners of exotic hadrons.
[ { "created": "Wed, 18 Jan 2023 11:31:56 GMT", "version": "v1" }, { "created": "Fri, 24 May 2024 10:51:48 GMT", "version": "v2" } ]
2024-05-27
[ [ "Luo", "Jin-Feng", "" ], [ "Wang", "Di", "" ] ]
Isospin symmetry is the most precise flavor symmetry. The effective Hamiltonian of charm quark weak decay is zero under the isospin lowering operators $I_-^n$, which permits us to generate isospin sum rules through several master formulas. In this work, we derive the master formulas of isospin sum rules for the two- and three-body non-leptonic decays of singly and doubly charmed baryons. Hundreds of isospin sum rules are derived to test of isospin symmetry and provide hints for the new decay modes. The isospin sum rules for multi-body decays are not broken by the intermediate resonances and hence can be used to study the isospin partners of exotic hadrons.
1808.10309
Natascia Vignaroli
Natascia Vignaroli
Seeking leptoquarks in the $\bf t\bar{t}$ plus missing energy channel at the high-luminosity LHC
19 pages, 8 figures. Matches version to appear in Physical Review D
Phys. Rev. D 99, 035021 (2019)
10.1103/PhysRevD.99.035021
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $t\bar t$ plus missing energy channel is one of the most efficient to detect third-generation leptoquarks (LQs). It offers an important test to models which explain flavor anomalies in $B$ meson decays. We outline a search strategy in the channel, relying on tagging the tops and on observables constructed out of the tops, and we assess the reach on LQs of the future high-luminosity LHC program. We find that with 3 ab$^{-1}$ a vector (scalar) LQ decaying 50% (100%) to top and neutrino can be excluded up to masses of 1.96 TeV (1.54 TeV). We also indicate several observables that, in case of a future discovery in the channel, can be used to distinguish a scalar LQ from a vector LQ. The implications of our findings to models addressing the recent flavor anomalies are finally discussed.
[ { "created": "Thu, 30 Aug 2018 14:18:52 GMT", "version": "v1" }, { "created": "Wed, 30 Jan 2019 14:17:12 GMT", "version": "v2" } ]
2019-02-20
[ [ "Vignaroli", "Natascia", "" ] ]
The $t\bar t$ plus missing energy channel is one of the most efficient to detect third-generation leptoquarks (LQs). It offers an important test to models which explain flavor anomalies in $B$ meson decays. We outline a search strategy in the channel, relying on tagging the tops and on observables constructed out of the tops, and we assess the reach on LQs of the future high-luminosity LHC program. We find that with 3 ab$^{-1}$ a vector (scalar) LQ decaying 50% (100%) to top and neutrino can be excluded up to masses of 1.96 TeV (1.54 TeV). We also indicate several observables that, in case of a future discovery in the channel, can be used to distinguish a scalar LQ from a vector LQ. The implications of our findings to models addressing the recent flavor anomalies are finally discussed.
2309.09155
Hoernisa Iminniyaz
Fangyu Liu, Hoernisa Iminniyaz
Constraints on Asymmetric Dark Matter Self Annihilation Cross Sections in Non-standard Cosmological Scenarios
14 pages, 6 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
We investigate the relic abundance of asymmetric dark matter in the non-standard cosmological scenarios when the annihilation cross section includes self annihilations. Here we discuss the kination model and brane world cosmology. When the self annihilation is permitted for asymmetric dark matter, there is possibility of washing out the pre-existed asymmetry. We find the constraints on the cross section to avoid the complete washing out of the asymmetry in the non-standard cosmological scenarios. The enhanced cosmic expansion rate causes the freeze out point of wash-out to be earlier. The larger self annihilation cross sections are allowed to exist in kination model and brane world cosmology. Then, in the case of left-handed sneutrino asymmetric dark matter, we find the value of the lower bound on winos mass is smaller than that in the standard cosmological scenario.
[ { "created": "Sun, 17 Sep 2023 04:43:05 GMT", "version": "v1" }, { "created": "Sun, 29 Oct 2023 12:57:39 GMT", "version": "v2" }, { "created": "Fri, 9 Feb 2024 04:43:34 GMT", "version": "v3" } ]
2024-02-12
[ [ "Liu", "Fangyu", "" ], [ "Iminniyaz", "Hoernisa", "" ] ]
We investigate the relic abundance of asymmetric dark matter in the non-standard cosmological scenarios when the annihilation cross section includes self annihilations. Here we discuss the kination model and brane world cosmology. When the self annihilation is permitted for asymmetric dark matter, there is possibility of washing out the pre-existed asymmetry. We find the constraints on the cross section to avoid the complete washing out of the asymmetry in the non-standard cosmological scenarios. The enhanced cosmic expansion rate causes the freeze out point of wash-out to be earlier. The larger self annihilation cross sections are allowed to exist in kination model and brane world cosmology. Then, in the case of left-handed sneutrino asymmetric dark matter, we find the value of the lower bound on winos mass is smaller than that in the standard cosmological scenario.
2202.03372
Christopher Cocuzza
C. Cocuzza, W. Melnitchouk, A. Metz, N. Sato
Polarized Antimatter in the Proton from Global QCD Analysis
4 figures
null
10.1103/PhysRevD.106.L031502
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the first simultaneous global QCD analysis of spin-dependent parton distribution functions alongside their spin-averaged counterparts and pion, kaon, and unidentified hadron fragmentation functions. This analysis includes all data relevant for constraining the polarized light quark sea asymmetry $\Delta \bar{u} - \Delta \bar{d}$, in particular the latest polarized $W$-lepton production data from the STAR collaboration at RHIC and semi-inclusive deep inelastic scattering data from COMPASS, allowing the most robust extraction available with minimal theoretical assumptions. We also extract a self-consistent set of antiquark polarization ratios $\Delta \bar{u}/\bar{u}$ and $\Delta \bar{d}/\bar{d}$ and determine the signs of the truncated contributions to the proton spin from the light antiquarks.
[ { "created": "Mon, 7 Feb 2022 17:43:26 GMT", "version": "v1" }, { "created": "Thu, 7 Sep 2023 15:13:28 GMT", "version": "v2" } ]
2023-09-08
[ [ "Cocuzza", "C.", "" ], [ "Melnitchouk", "W.", "" ], [ "Metz", "A.", "" ], [ "Sato", "N.", "" ] ]
We present the first simultaneous global QCD analysis of spin-dependent parton distribution functions alongside their spin-averaged counterparts and pion, kaon, and unidentified hadron fragmentation functions. This analysis includes all data relevant for constraining the polarized light quark sea asymmetry $\Delta \bar{u} - \Delta \bar{d}$, in particular the latest polarized $W$-lepton production data from the STAR collaboration at RHIC and semi-inclusive deep inelastic scattering data from COMPASS, allowing the most robust extraction available with minimal theoretical assumptions. We also extract a self-consistent set of antiquark polarization ratios $\Delta \bar{u}/\bar{u}$ and $\Delta \bar{d}/\bar{d}$ and determine the signs of the truncated contributions to the proton spin from the light antiquarks.
hep-ph/0002035
Michael Spira
S. Dittmaier, M. Kr\"amer, Y. Liao, M. Spira and P.M. Zerwas
Higgs radiation off quarks in supersymmetric theories at e^+e^- colliders
12 pages, latex, 3 figures
Phys.Lett. B478 (2000) 247-254
10.1016/S0370-2693(00)00278-1
DESY 99-177, BI-TP 99/27, Edinburgh 2000/03
hep-ph
null
Yukawa couplings between Higgs bosons and quarks in supersymmetric theories can be measured in the processes e^+e^- -> Q Qbar + Higgs. We have determined the cross sections of these processes in the minimal supersymmetric model including the complete set of next-to-leading order QCD corrections for all channels.
[ { "created": "Thu, 3 Feb 2000 08:53:54 GMT", "version": "v1" } ]
2016-09-06
[ [ "Dittmaier", "S.", "" ], [ "Krämer", "M.", "" ], [ "Liao", "Y.", "" ], [ "Spira", "M.", "" ], [ "Zerwas", "P. M.", "" ] ]
Yukawa couplings between Higgs bosons and quarks in supersymmetric theories can be measured in the processes e^+e^- -> Q Qbar + Higgs. We have determined the cross sections of these processes in the minimal supersymmetric model including the complete set of next-to-leading order QCD corrections for all channels.
1101.4410
Danny Marfatia
V. Barger, Y. Gao, D. Marfatia
Dark matter at DeepCore and IceCube
23 pages, 7 figures, 4 tables. Version to appear in PRD
Phys.Rev.D83:055012,2011
10.1103/PhysRevD.83.055012
null
hep-ph astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With the augmentation of IceCube by DeepCore, the prospect for detecting dark matter annihilation in the Sun is much improved. To complement this experimental development, we provide a thorough template analysis of the particle physics issues that are necessary to precisely interpret the data. Our study is about nitty-gritty and is intended as a framework for detailed work on a variety of dark matter candidates. To accurately predict the source neutrino spectrum, we account for spin correlations of the final state particles and the helicity-dependence of their decays, and absorption effects at production. We fully treat the propagation of neutrinos through the Sun, including neutrino oscillations, energy losses and tau regeneration. We simulate the survival probability of muons produced in the Earth by using the Muon Monte Carlo program, reproduce the published IceCube effective area, and update the parameters in the differential equation that approximates muon energy losses. To evaluate the zenith-angle dependent atmospheric background event rate, we track the Sun and determine the time it spends at each zenith angle. Throughout, we employ neutralino dark matter as our example.
[ { "created": "Sun, 23 Jan 2011 22:47:24 GMT", "version": "v1" }, { "created": "Fri, 25 Feb 2011 16:53:08 GMT", "version": "v2" } ]
2015-03-17
[ [ "Barger", "V.", "" ], [ "Gao", "Y.", "" ], [ "Marfatia", "D.", "" ] ]
With the augmentation of IceCube by DeepCore, the prospect for detecting dark matter annihilation in the Sun is much improved. To complement this experimental development, we provide a thorough template analysis of the particle physics issues that are necessary to precisely interpret the data. Our study is about nitty-gritty and is intended as a framework for detailed work on a variety of dark matter candidates. To accurately predict the source neutrino spectrum, we account for spin correlations of the final state particles and the helicity-dependence of their decays, and absorption effects at production. We fully treat the propagation of neutrinos through the Sun, including neutrino oscillations, energy losses and tau regeneration. We simulate the survival probability of muons produced in the Earth by using the Muon Monte Carlo program, reproduce the published IceCube effective area, and update the parameters in the differential equation that approximates muon energy losses. To evaluate the zenith-angle dependent atmospheric background event rate, we track the Sun and determine the time it spends at each zenith angle. Throughout, we employ neutralino dark matter as our example.
1909.12113
Nirbhay Kumar Behera Dr.
Nirbhay Kumar Behera, Ranjit Kumar Nayak and Sadhana Dash
Baseline study for net-proton number fluctuations at top energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider with the Angantyr model
14 pages, 9 figures, Published version
Phys. Rev. C 101, 064903 (2020)
10.1103/PhysRevC.101.064903
null
hep-ph hep-ex nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The multiplicity percentile dependence of cumulants, of net-proton number distributions in Au$-$Au collisions at $\sqrt{s_{NN}} = $ 200 GeV and Pb$-$Pb collisions at $\sqrt{s_{NN}} = $ 2.76 TeV has been investigated using the Angantyr model (the heavy-ion extension of the \textsc{Pythia 8} model). The effects of finite transverse momentum ($p_{\mathrm T}$) and pseudorapidity ($\eta$) acceptance on the net-proton cumulants have also been studied. Furthermore, the effects of the hydrodynamic expansion and feed down from weak decays were explored. It was found that radial flow has substantial impact on the cumulants and their ratios, while weak decays have a finite but relatively smaller effect. The obtained values of cumulants and their ratios with the Angantyr model, where the formation of thermalized medium is not assumed can serve as a baseline for future measurements.
[ { "created": "Thu, 26 Sep 2019 14:01:52 GMT", "version": "v1" }, { "created": "Sun, 14 Jun 2020 17:41:29 GMT", "version": "v2" } ]
2020-07-01
[ [ "Behera", "Nirbhay Kumar", "" ], [ "Nayak", "Ranjit Kumar", "" ], [ "Dash", "Sadhana", "" ] ]
The multiplicity percentile dependence of cumulants, of net-proton number distributions in Au$-$Au collisions at $\sqrt{s_{NN}} = $ 200 GeV and Pb$-$Pb collisions at $\sqrt{s_{NN}} = $ 2.76 TeV has been investigated using the Angantyr model (the heavy-ion extension of the \textsc{Pythia 8} model). The effects of finite transverse momentum ($p_{\mathrm T}$) and pseudorapidity ($\eta$) acceptance on the net-proton cumulants have also been studied. Furthermore, the effects of the hydrodynamic expansion and feed down from weak decays were explored. It was found that radial flow has substantial impact on the cumulants and their ratios, while weak decays have a finite but relatively smaller effect. The obtained values of cumulants and their ratios with the Angantyr model, where the formation of thermalized medium is not assumed can serve as a baseline for future measurements.
0908.2186
Kai Wang
Tao Han, Hai-Shan Liu, Ming-xing Luo, Kai Wang, Wei Wu
Like-sign Di-lepton Signals in Higgsless Models at the LHC
13 pages, 7 figures
Phys.Rev.D80:095010,2009
10.1103/PhysRevD.80.095010
MADPH-09-1535, ZIMP-09-03, IPMU-09-0072, CAS-KITPC/ITP-131
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the potential LHC discovery of the Z1 KK gauge boson unitarizing longitudinal W+W- scattering amplitude. In particular, we explore the decay mode Z1->t tbar along with Z1-> W+W- without specifying the branching fractions. We propose to exploit the associated production pp-> W Z1, and select the final state of like-sign dileptons plus multijets and large missing energy. We conclude that it is possible to observe the Z1 resonance at a 5 sigma level with an integrated luminosity of 100 inverse fb at the LHC upto 650 GeV for a dominant WW channel, and 560 GeV for a dominant ttbar channel.
[ { "created": "Sat, 15 Aug 2009 14:51:29 GMT", "version": "v1" } ]
2010-12-09
[ [ "Han", "Tao", "" ], [ "Liu", "Hai-Shan", "" ], [ "Luo", "Ming-xing", "" ], [ "Wang", "Kai", "" ], [ "Wu", "Wei", "" ] ]
We study the potential LHC discovery of the Z1 KK gauge boson unitarizing longitudinal W+W- scattering amplitude. In particular, we explore the decay mode Z1->t tbar along with Z1-> W+W- without specifying the branching fractions. We propose to exploit the associated production pp-> W Z1, and select the final state of like-sign dileptons plus multijets and large missing energy. We conclude that it is possible to observe the Z1 resonance at a 5 sigma level with an integrated luminosity of 100 inverse fb at the LHC upto 650 GeV for a dominant WW channel, and 560 GeV for a dominant ttbar channel.
1507.05640
Davide Pagani
Fabio Maltoni, Davide Pagani, Ioannis Tsinikos
Associated production of a top-quark pair with vector bosons at NLO in QCD: impact on $t \bar{t} H$ searches at the LHC
44 pages, 23 figures. Version published on JHEP, typos in Table 5 have been corrected
null
10.1007/JHEP02(2016)113
CP3-15-20
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the production of a top-quark pair in association with one and two vector bosons, $t \bar t V$ and $t \bar t VV$ with $V=\gamma, Z, W^\pm$, at the LHC. We provide predictions at next-to-leading order in QCD for total cross sections and top-quark charge asymmetries as well as for differential distributions. A thorough discussion of the residual theoretical uncertainties related to missing higher orders and to parton distribution functions is presented. As an application, we calculate the total cross sections for this class of processes (together with $t \bar t H$ and $t \bar t t \bar t$ production) at hadron colliders for energies up to 100 TeV. In addition, by matching the NLO calculation to a parton shower, we determine the contribution of $t \bar t V$ and $t \bar t VV$ to final state signatures (two-photon and two-same-sign-, three- and four-lepton) relevant for $t \bar t H$ analyses at the Run II of the LHC.
[ { "created": "Mon, 20 Jul 2015 20:07:48 GMT", "version": "v1" }, { "created": "Mon, 4 Apr 2016 15:55:41 GMT", "version": "v2" } ]
2016-04-05
[ [ "Maltoni", "Fabio", "" ], [ "Pagani", "Davide", "" ], [ "Tsinikos", "Ioannis", "" ] ]
We study the production of a top-quark pair in association with one and two vector bosons, $t \bar t V$ and $t \bar t VV$ with $V=\gamma, Z, W^\pm$, at the LHC. We provide predictions at next-to-leading order in QCD for total cross sections and top-quark charge asymmetries as well as for differential distributions. A thorough discussion of the residual theoretical uncertainties related to missing higher orders and to parton distribution functions is presented. As an application, we calculate the total cross sections for this class of processes (together with $t \bar t H$ and $t \bar t t \bar t$ production) at hadron colliders for energies up to 100 TeV. In addition, by matching the NLO calculation to a parton shower, we determine the contribution of $t \bar t V$ and $t \bar t VV$ to final state signatures (two-photon and two-same-sign-, three- and four-lepton) relevant for $t \bar t H$ analyses at the Run II of the LHC.
hep-ph/9911268
Baldicchi Massimiliano
M. Baldicchi (Milano Univ.)
First principle quadratic and linear mass operators, quarkonium spectrum and Regge trajectories
6 pages, 2 figures, Talk given at the XVII Autumn School "QCD: Perturbative or Nonperturbative?", Lisbon (Portugal), September 29 - October 4, 1999. To appear in the proceedings
null
null
null
hep-ph
null
In previous works, a squared mass operator M^2 and a more common centre of frame Hamiltonian H_CM for the quark-antiquark system were obtained by using the only assumption that ln W (W being the Wilson loop correlator) can be written in QCD as the sum of its perturbative expression and an area term. We evaluated the spectrum of these operators by neglecting all the spin-dependent terms but for a spin-spin term. We succeeded in reproducing rather well the entire meson spectrum and for the light-light systems we found straight Regge trajectories with the right slope and intercepts. A first attempt to study the contribution of the spin dependent terms has been made.
[ { "created": "Mon, 8 Nov 1999 11:51:15 GMT", "version": "v1" }, { "created": "Tue, 9 Nov 1999 13:50:19 GMT", "version": "v2" } ]
2007-05-23
[ [ "Baldicchi", "M.", "", "Milano Univ." ] ]
In previous works, a squared mass operator M^2 and a more common centre of frame Hamiltonian H_CM for the quark-antiquark system were obtained by using the only assumption that ln W (W being the Wilson loop correlator) can be written in QCD as the sum of its perturbative expression and an area term. We evaluated the spectrum of these operators by neglecting all the spin-dependent terms but for a spin-spin term. We succeeded in reproducing rather well the entire meson spectrum and for the light-light systems we found straight Regge trajectories with the right slope and intercepts. A first attempt to study the contribution of the spin dependent terms has been made.
hep-ph/0701003
Sukanta Panda
Namit Mahajan and Sukanta Panda
Probing Low-x QCD With Very High Energy Prompt Muons
5 pages, 2 figures
null
null
null
hep-ph astro-ph hep-ex
null
We explore the possibility of utilizing the prompt muon fluxes at very high energies in order to discriminate various models/parametrizations of low-x QCD behaviour of hadronic cross-sections relevant at such energies. We find that the pair meter technique for measuring high energy prompt muons can be very efficient in such an endeavor. As a by product, it allows to cleanly probe the change in composition of the primary cosmic rays expected at high energies.
[ { "created": "Sun, 31 Dec 2006 10:18:55 GMT", "version": "v1" } ]
2007-05-23
[ [ "Mahajan", "Namit", "" ], [ "Panda", "Sukanta", "" ] ]
We explore the possibility of utilizing the prompt muon fluxes at very high energies in order to discriminate various models/parametrizations of low-x QCD behaviour of hadronic cross-sections relevant at such energies. We find that the pair meter technique for measuring high energy prompt muons can be very efficient in such an endeavor. As a by product, it allows to cleanly probe the change in composition of the primary cosmic rays expected at high energies.
hep-ph/0002276
Christian Schubert
Christian Schubert (LAPTH Annecy-le-Vieux)
Vacuum Polarisation Tensors in Constant Electromagnetic Fields: Part II
18 pages, standard Latex, 1 figure
Nucl.Phys. B585 (2000) 429-442
10.1016/S0550-3213(00)00424-7
LAPTH-783/2000
hep-ph hep-th
null
In the second part of this series we apply the ``string-inspired'' technique to the calculation of one-loop amplitudes involving both vectors and axialvectors, as well as a general constant electromagnetic background field. The vector-axialvector two-point function in a constant field is calculated explicitly.
[ { "created": "Fri, 25 Feb 2000 18:42:20 GMT", "version": "v1" } ]
2009-10-31
[ [ "Schubert", "Christian", "", "LAPTH Annecy-le-Vieux" ] ]
In the second part of this series we apply the ``string-inspired'' technique to the calculation of one-loop amplitudes involving both vectors and axialvectors, as well as a general constant electromagnetic background field. The vector-axialvector two-point function in a constant field is calculated explicitly.
0708.2521
Mariana Kirchbach
C. B. Compean, M. Kirchbach
Trigonometric quark confinement potential of QCD traits
4 pages, 5 figures
Eur.Phys.J.A33:1-4,2007
10.1140/epja/i2007-10444-0
null
hep-ph nucl-th
null
We make the case that the Coulomb- plus linear quark confinement potential predicted by lattice QCD is an approximation to the exactly solvable trigonometric Rosen-Morse potential that has the property to interpolate between the Coulomb- and the infinite wells. We test the predictive power of this potential in the description of the nucleon (considered as a quark-diquark system) and provide analytic expressions for its mass spectrum and the proton electric form factor. We compare the results obtained in this fashion to data and find quite good agreement. We obtain an effective gluon propagator in closed form as the Fourier transform of the potential under investigation.
[ { "created": "Mon, 20 Aug 2007 19:25:17 GMT", "version": "v1" } ]
2008-11-26
[ [ "Compean", "C. B.", "" ], [ "Kirchbach", "M.", "" ] ]
We make the case that the Coulomb- plus linear quark confinement potential predicted by lattice QCD is an approximation to the exactly solvable trigonometric Rosen-Morse potential that has the property to interpolate between the Coulomb- and the infinite wells. We test the predictive power of this potential in the description of the nucleon (considered as a quark-diquark system) and provide analytic expressions for its mass spectrum and the proton electric form factor. We compare the results obtained in this fashion to data and find quite good agreement. We obtain an effective gluon propagator in closed form as the Fourier transform of the potential under investigation.
hep-ph/0008278
Paul H. Frampton
Paul H. Frampton
Economic Model for Neutrino Masses and Mixings
3 pages LaTeX. Write-up of talk at DPF2000, August 9,2000
Int.J.Mod.Phys. A16S1B (2001) 701-703
10.1142/S0217751X01007832
IFP-786-UNC
hep-ph
null
Working in the framework of three chiral neutrinos with Majorana masses, we investigate a scenario where the neutrino mass matrix is strictly off-diagonal in the flavor basis, with all its diagonal entries precisely zero.
[ { "created": "Sat, 26 Aug 2000 22:58:02 GMT", "version": "v1" } ]
2009-10-31
[ [ "Frampton", "Paul H.", "" ] ]
Working in the framework of three chiral neutrinos with Majorana masses, we investigate a scenario where the neutrino mass matrix is strictly off-diagonal in the flavor basis, with all its diagonal entries precisely zero.
hep-ph/9508276
null
D. Kharzeev and H. Satz
Charmonium Composition and Nuclear Suppression
Plain TeX, 8 pages, 5 figures available upon request
Phys.Lett.B366:316-322,1996
10.1016/0370-2693(95)01328-8
CERN-TH/95-214, BI-TP 95/30
hep-ph nucl-th
null
We study charmonium production in hadron-nucleus collisions through the intermediate next-to-leading Fock space component $|(\bar{c}c)_8 g>$, formed by a colour octet $\bar{c}c$ pair and a gluon. We estimate the size of this state and show that its interaction with nucleons accounts for the observed charmonium suppression in nuclear interactions.
[ { "created": "Thu, 10 Aug 1995 16:35:40 GMT", "version": "v1" } ]
2010-11-19
[ [ "Kharzeev", "D.", "" ], [ "Satz", "H.", "" ] ]
We study charmonium production in hadron-nucleus collisions through the intermediate next-to-leading Fock space component $|(\bar{c}c)_8 g>$, formed by a colour octet $\bar{c}c$ pair and a gluon. We estimate the size of this state and show that its interaction with nucleons accounts for the observed charmonium suppression in nuclear interactions.
1905.09143
Kazunori Nakayama
Kazunori Nakayama
A Note on Gravitational Particle Production in Supergravity
16 pages, 1 figure
null
10.1016/j.physletb.2019.134857
UT-19-11
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is pointed out that the gravitational particle production rate of a scalar component of a chiral superfield in supergravity with minimal Kahler potential can be significantly suppressed compared with a minimal scalar field in non-supersymmetric Einstein gravity. This suppression is avoided for some choice of the inflaton sector and also for non-minimal Kahler potential of the chiral superfield.
[ { "created": "Wed, 22 May 2019 13:53:29 GMT", "version": "v1" } ]
2019-08-14
[ [ "Nakayama", "Kazunori", "" ] ]
It is pointed out that the gravitational particle production rate of a scalar component of a chiral superfield in supergravity with minimal Kahler potential can be significantly suppressed compared with a minimal scalar field in non-supersymmetric Einstein gravity. This suppression is avoided for some choice of the inflaton sector and also for non-minimal Kahler potential of the chiral superfield.
hep-ph/0212362
Hiroshi Yokota
Yuko Fueki, Hisao Nakkagawa, Hiroshi Yokota, Koji Yoshida
Chiral Phase Transitions in QED at Finite Temperature: Dyson-Schwinger Equation Analysis in the Real Time Hard-Thermal-Loop Approximation
Revtex4 with 6 figures, 11 pages
Prog.Theor.Phys. 110 (2003) 777-789
10.1143/PTP.110.777
null
hep-ph
null
In order for clarifying what are the essential thermal effects that govern the chiral phase transition at finite temperature, we investigate, in the real-time thermal QED, the consequences of the Hard-Thermal-Loop (HTL) resummed Dyson-Schwinger equation for the physical fermion mass function $\Sigma_R$. Since $\Sigma_R$ is the mass function of an ``unstable'' quasi-particle in thermal field theories, it necessarily has non-trivial imaginary parts together with non-trivial wave function renormalization constants. In the present analysis we correctly respect this fact, and study, in the ladder approximation, the effect of HTL resummed gauge boson propagator. Our results with the use of numerical analysis, show the two facts; i) The chiral phase transition is of second order, since the fermion mass is dynamically generated at a critical value of the temperature $T_c$, or at the critical coupling constant $\alpha_c$, without any discontinuity, and ii) the critical temperature $T_c$ at fixed value of $\alpha$ is significantly lower than the previous results, namely the restoration of chiral symmetry occurs at lower temperature than previously expected. The second fact shows the importance of correctly taking the essential thermal effect into the analysis of chiral phase transition, which are, in the previous analyses, neglected due to the inappropriate approximations. The procedure how to maximally respect the gauge invariance in the present approximation, is also discussed.
[ { "created": "Wed, 25 Dec 2002 09:53:44 GMT", "version": "v1" } ]
2009-11-07
[ [ "Fueki", "Yuko", "" ], [ "Nakkagawa", "Hisao", "" ], [ "Yokota", "Hiroshi", "" ], [ "Yoshida", "Koji", "" ] ]
In order for clarifying what are the essential thermal effects that govern the chiral phase transition at finite temperature, we investigate, in the real-time thermal QED, the consequences of the Hard-Thermal-Loop (HTL) resummed Dyson-Schwinger equation for the physical fermion mass function $\Sigma_R$. Since $\Sigma_R$ is the mass function of an ``unstable'' quasi-particle in thermal field theories, it necessarily has non-trivial imaginary parts together with non-trivial wave function renormalization constants. In the present analysis we correctly respect this fact, and study, in the ladder approximation, the effect of HTL resummed gauge boson propagator. Our results with the use of numerical analysis, show the two facts; i) The chiral phase transition is of second order, since the fermion mass is dynamically generated at a critical value of the temperature $T_c$, or at the critical coupling constant $\alpha_c$, without any discontinuity, and ii) the critical temperature $T_c$ at fixed value of $\alpha$ is significantly lower than the previous results, namely the restoration of chiral symmetry occurs at lower temperature than previously expected. The second fact shows the importance of correctly taking the essential thermal effect into the analysis of chiral phase transition, which are, in the previous analyses, neglected due to the inappropriate approximations. The procedure how to maximally respect the gauge invariance in the present approximation, is also discussed.
1412.1400
Sergei Gninenko
S.N. Gninenko, N.V. Krasnikov, V.A. Matveev
Muon g-2 and searches for a new leptophobic sub-GeV dark boson in a missing-energy experiment at CERN
13 pages, 9 figures. Version to appear in PRD, refs. and discussions added, title modified in journal
Phys. Rev. D91 (2015) 095015
10.1103/PhysRevD.91.095015
null
hep-ph hep-ex physics.ins-det
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The 3.6 \sigma discrepancy between the predicted and measured values of the anomalous magnetic moment of positive muons can be explained by the existence of a new dark boson Z_\mu with a mass in the sub-GeV range, which is coupled predominantly to the second and third lepton generations through the L_\mu - L_\tau current . After a discussion of the present phenomenological bounds on the Z_\mu coupling, we show that if the Z_\mu exists, it could be observed in the reaction \mu+Z \to \mu+Z+Z_\mu of a muon scattering off nuclei by looking for an excess of events with large missing muon beam energy in a detector due to the prompt bremsstrahlung Z_\mu decay Z_\mu \to \nu\nu into a couple of neutrinos. We describe the experimental technique and the preliminary study of the feasibility for the proposed search. We show that this specific signal allows for a the search for the Z_\mu with a sensitivity in the coupling constant \alpha_\mu > 10^{-11}, which is 3 orders of magnitude higher than the value required to explain the discrepancy. We point out that the availability of high-energy and -intensity muon beams at CERN SPS provides a unique opportunity to either discover or rule out the Z_\mu in the proposed search in the near future. The experiment is based on the missing-energy approach developed for the searches for invisible decays of dark photons and (pseudo)scalar mesons at CERN and is complementary to these experiments.
[ { "created": "Wed, 3 Dec 2014 16:54:32 GMT", "version": "v1" }, { "created": "Mon, 11 May 2015 14:34:14 GMT", "version": "v2" } ]
2015-05-21
[ [ "Gninenko", "S. N.", "" ], [ "Krasnikov", "N. V.", "" ], [ "Matveev", "V. A.", "" ] ]
The 3.6 \sigma discrepancy between the predicted and measured values of the anomalous magnetic moment of positive muons can be explained by the existence of a new dark boson Z_\mu with a mass in the sub-GeV range, which is coupled predominantly to the second and third lepton generations through the L_\mu - L_\tau current . After a discussion of the present phenomenological bounds on the Z_\mu coupling, we show that if the Z_\mu exists, it could be observed in the reaction \mu+Z \to \mu+Z+Z_\mu of a muon scattering off nuclei by looking for an excess of events with large missing muon beam energy in a detector due to the prompt bremsstrahlung Z_\mu decay Z_\mu \to \nu\nu into a couple of neutrinos. We describe the experimental technique and the preliminary study of the feasibility for the proposed search. We show that this specific signal allows for a the search for the Z_\mu with a sensitivity in the coupling constant \alpha_\mu > 10^{-11}, which is 3 orders of magnitude higher than the value required to explain the discrepancy. We point out that the availability of high-energy and -intensity muon beams at CERN SPS provides a unique opportunity to either discover or rule out the Z_\mu in the proposed search in the near future. The experiment is based on the missing-energy approach developed for the searches for invisible decays of dark photons and (pseudo)scalar mesons at CERN and is complementary to these experiments.
2006.16273
Jeriek Van den Abeele
Andy Buckley, Anders Kvellestad, Are Raklev, Pat Scott, Jon Vegard Sparre, Jeriek Van den Abeele, Ingrid A. Vazquez-Holm
$\textsf{Xsec}$: the cross-section evaluation code
Accepted version
Eur. Phys. J. C 80, 1106 (2020)
10.1140/epjc/s10052-020-08635-y
SAGEX-20-17-E
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The evaluation of higher-order cross-sections is an important component in the search for new physics, both at hadron colliders and elsewhere. For most new physics processes of interest, total cross-sections are known at next-to-leading order (NLO) in the strong coupling $\alpha_s$, and often beyond, via either higher-order terms at fixed powers of $\alpha_s$, or multi-emission resummation. However, the computation time for such higher-order cross-sections is prohibitively expensive, and precludes efficient evaluation in parameter-space scans beyond two dimensions. Here we describe the software tool $\textsf{xsec}$, which allows for fast evaluation of cross-sections based on the use of machine-learning regression, using distributed Gaussian processes trained on a pre-generated sample of parameter points. This first version of the code provides all NLO Minimal Supersymmetric Standard Model strong-production cross-sections at the LHC, for individual flavour final states, evaluated in a fraction of a second. Moreover, it calculates regression errors, as well as estimates of errors from higher-order contributions, from uncertainties in the parton distribution functions, and from the value of $\alpha_s$. While we focus on a specific phenomenological model of supersymmetry, the method readily generalises to any process where it is possible to generate a sufficient training sample.
[ { "created": "Mon, 29 Jun 2020 18:01:13 GMT", "version": "v1" }, { "created": "Fri, 18 Dec 2020 19:00:02 GMT", "version": "v2" } ]
2020-12-29
[ [ "Buckley", "Andy", "" ], [ "Kvellestad", "Anders", "" ], [ "Raklev", "Are", "" ], [ "Scott", "Pat", "" ], [ "Sparre", "Jon Vegard", "" ], [ "Abeele", "Jeriek Van den", "" ], [ "Vazquez-Holm", "Ingrid A.", "...
The evaluation of higher-order cross-sections is an important component in the search for new physics, both at hadron colliders and elsewhere. For most new physics processes of interest, total cross-sections are known at next-to-leading order (NLO) in the strong coupling $\alpha_s$, and often beyond, via either higher-order terms at fixed powers of $\alpha_s$, or multi-emission resummation. However, the computation time for such higher-order cross-sections is prohibitively expensive, and precludes efficient evaluation in parameter-space scans beyond two dimensions. Here we describe the software tool $\textsf{xsec}$, which allows for fast evaluation of cross-sections based on the use of machine-learning regression, using distributed Gaussian processes trained on a pre-generated sample of parameter points. This first version of the code provides all NLO Minimal Supersymmetric Standard Model strong-production cross-sections at the LHC, for individual flavour final states, evaluated in a fraction of a second. Moreover, it calculates regression errors, as well as estimates of errors from higher-order contributions, from uncertainties in the parton distribution functions, and from the value of $\alpha_s$. While we focus on a specific phenomenological model of supersymmetry, the method readily generalises to any process where it is possible to generate a sufficient training sample.
2012.10228
Fu-Hu Liu
Pei-Pin Yang, Mai-Ying Duan, Fu-Hu Liu
Dependence of related parameters on centrality and mass in a new treatment for transverse momentum spectra in high energy collisions
34 pages, 16 figures. The European Physical Journal A, accepted
The European Physical Journal A 57, 63 (2021) (32 pages)
10.1140/epja/s10050-021-00380-4
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We collected the experimental data of transverse momentum spectra of identified particles produced in proton-proton ($p$-$p$), deuteron-gold ($d$-Au or $d$-$A$), gold-gold (Au-Au or $A$-$A$), proton-lead ($p$-Pb or $p$-$A$), and lead-lead (Pb-Pb or $A$-$A$) collisions measured by the ALICE, CMS, LHCb, NA49, NA61/SHINE, PHENIX, and STAR collaborations at different center-of mass energies. The multisource thermal model at the quark level or the participant quark model is used to describe the experimental data. The free parameters, the effective temperature $T$, entropy index-related $n$, and revised index $a_{0}$, in the revised Tsallis--Pareto-type function are extracted at the quark level. In most cases, $T$ and $n$ in central collisions are larger than those in peripheral collisions, and $a_0$ does not change in different centrality classes. With the increase in the mass of produced particle or participant quark, $T$ and $a_0$ increase, and $n$ does not change significantly. The behaviors of related parameters from $p$-$p$, $p(d)$-$A$, and $A$-$A$ collisions are similar.
[ { "created": "Fri, 18 Dec 2020 13:47:08 GMT", "version": "v1" }, { "created": "Fri, 29 Jan 2021 13:34:54 GMT", "version": "v2" } ]
2021-02-19
[ [ "Yang", "Pei-Pin", "" ], [ "Duan", "Mai-Ying", "" ], [ "Liu", "Fu-Hu", "" ] ]
We collected the experimental data of transverse momentum spectra of identified particles produced in proton-proton ($p$-$p$), deuteron-gold ($d$-Au or $d$-$A$), gold-gold (Au-Au or $A$-$A$), proton-lead ($p$-Pb or $p$-$A$), and lead-lead (Pb-Pb or $A$-$A$) collisions measured by the ALICE, CMS, LHCb, NA49, NA61/SHINE, PHENIX, and STAR collaborations at different center-of mass energies. The multisource thermal model at the quark level or the participant quark model is used to describe the experimental data. The free parameters, the effective temperature $T$, entropy index-related $n$, and revised index $a_{0}$, in the revised Tsallis--Pareto-type function are extracted at the quark level. In most cases, $T$ and $n$ in central collisions are larger than those in peripheral collisions, and $a_0$ does not change in different centrality classes. With the increase in the mass of produced particle or participant quark, $T$ and $a_0$ increase, and $n$ does not change significantly. The behaviors of related parameters from $p$-$p$, $p(d)$-$A$, and $A$-$A$ collisions are similar.
hep-ph/9610215
Michael Rueter
Michael Rueter (ITP Universit\"at Heidelberg)
Low energy theorems and the SU(3)-flux-tube
4 pages, LaTeX, sprocl.sty, epsf.sty, 5 figures PostScript available at: http://www.thphys.uni-heidelberg.de/~rueter/Publications.html to appear in the proceedings of "Quark confinement and the hadron spectrum II", Como, 1996
null
null
null
hep-ph
null
The total energy and action, which is stored in the flux-tube between a static quark-antiquark pair, can be compared with the potential of the pair with the help of two low energy theorems. The flux-tube and the potential are calculated in the framework of the model of the stochastic vacuum. Using the low energy theorems we obtain consistency of the results and can predict the scale where the model describes the non-perturbative gluon dynamics of QCD.
[ { "created": "Wed, 2 Oct 1996 12:36:04 GMT", "version": "v1" } ]
2007-05-23
[ [ "Rueter", "Michael", "", "ITP Universität Heidelberg" ] ]
The total energy and action, which is stored in the flux-tube between a static quark-antiquark pair, can be compared with the potential of the pair with the help of two low energy theorems. The flux-tube and the potential are calculated in the framework of the model of the stochastic vacuum. Using the low energy theorems we obtain consistency of the results and can predict the scale where the model describes the non-perturbative gluon dynamics of QCD.
1008.1936
Thomas Becher
Thomas Becher and Guido Bell
The gluon jet function at two-loop order
12 pages, 2 figures
Phys.Lett.B695:252-258,2011
10.1016/j.physletb.2010.11.036
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The inclusive gluon jet function is evaluated at two-loop accuracy. This function is relevant for resummations of large perturbative logarithms in collider processes involving low-mass gluon jets. The jet function corresponds to the imaginary part of the gluon propagator in light-cone gauge, which is adopted for the calculation. In addition to the leading jet function, the power-suppressed two-gluon jet functions are given and their renormalization is discussed.
[ { "created": "Wed, 11 Aug 2010 15:25:54 GMT", "version": "v1" } ]
2011-06-27
[ [ "Becher", "Thomas", "" ], [ "Bell", "Guido", "" ] ]
The inclusive gluon jet function is evaluated at two-loop accuracy. This function is relevant for resummations of large perturbative logarithms in collider processes involving low-mass gluon jets. The jet function corresponds to the imaginary part of the gluon propagator in light-cone gauge, which is adopted for the calculation. In addition to the leading jet function, the power-suppressed two-gluon jet functions are given and their renormalization is discussed.
hep-ph/9801291
M. Rysavy
J. Rizek, V. Brabec, O. Dragoun, M. Rysavy, A. Spalek
A possible origin of the endpoint anomaly in tritium beta-spectrum
9 pages, no figures. Requires file myown.sty (included)
null
null
NPI Rez - EXP - 01/98
hep-ph
null
The influence of the residual T atoms appearing after the decay of T_2 molecule on the beta-spectrum shape is considered. Recent experiments performed in Mainz, Troitsk, and Livermore are briefly reviewed from this viewpoint. Aspects connected with the possible time dependent change of the tritium source composition are discussed.
[ { "created": "Wed, 14 Jan 1998 08:45:25 GMT", "version": "v1" } ]
2007-05-23
[ [ "Rizek", "J.", "" ], [ "Brabec", "V.", "" ], [ "Dragoun", "O.", "" ], [ "Rysavy", "M.", "" ], [ "Spalek", "A.", "" ] ]
The influence of the residual T atoms appearing after the decay of T_2 molecule on the beta-spectrum shape is considered. Recent experiments performed in Mainz, Troitsk, and Livermore are briefly reviewed from this viewpoint. Aspects connected with the possible time dependent change of the tritium source composition are discussed.
1108.1058
Aqeel Ahmed
Aqeel Ahmed, Ishtiaq Ahmed, M. Ali Paracha, M. Junaid, Abdur Rehman and M. Jamil Aslam
Comparative Study of B_{c} --> D_{s}^{*}l^{+}l^{-} Decays in Standard Model and Supersymmetric Models
32 pages, 7 figures, v3 some typos removed and discussion improved on FBA
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A comparative study of the exclusive rare $B_{c}\rightarrow D_{s}^{\ast}\ell^{+}\ell^{-}$ ($\ell=\mu, \tau$) decays has been made in the minimal supersymmetric models (MSSM) and the SUSY SO(10) GUT models. In this context, various physical observables such as branching ratios $(\mathcal{BR})$, forward-backward asymmetries $(\mathcal{A}_{FB})$, lepton polarization asymmetries $(P_{L,N,T})$ and helicity fractions ($f_{L,T}$) of $D_{s}^{\ast}$ meson by using the the QCD sum rules form factors have been investigated. It is found that the SUSY effects are characteristically prominent to that of the SM values for these observables. For instance, in SUSY I and SUSY II, the forward-backward asymmetry does not cross zero which is mainly due to the same sign of the $C_{7}^{eff}$ and $C_{9}^{eff}$ Wilson coefficients. Similarly in SUSY SO(10) GUT models due to the complex nature of the new Wilson coefficients -- corresponding to the new operators arising due to the contribution of neutral Higgs bosons (NHBs) -- the above mentioned observables are sizably affected. Therefore the analysis of said observables in charmed semileptonic $B$ meson decays can put some stringent constraints on the parameter space of SUSY variants and can serve as a windowpane to look beyond the SM.
[ { "created": "Thu, 4 Aug 2011 12:15:04 GMT", "version": "v1" }, { "created": "Thu, 22 Sep 2011 10:16:35 GMT", "version": "v2" }, { "created": "Thu, 24 Nov 2011 13:16:28 GMT", "version": "v3" } ]
2011-11-28
[ [ "Ahmed", "Aqeel", "" ], [ "Ahmed", "Ishtiaq", "" ], [ "Paracha", "M. Ali", "" ], [ "Junaid", "M.", "" ], [ "Rehman", "Abdur", "" ], [ "Aslam", "M. Jamil", "" ] ]
A comparative study of the exclusive rare $B_{c}\rightarrow D_{s}^{\ast}\ell^{+}\ell^{-}$ ($\ell=\mu, \tau$) decays has been made in the minimal supersymmetric models (MSSM) and the SUSY SO(10) GUT models. In this context, various physical observables such as branching ratios $(\mathcal{BR})$, forward-backward asymmetries $(\mathcal{A}_{FB})$, lepton polarization asymmetries $(P_{L,N,T})$ and helicity fractions ($f_{L,T}$) of $D_{s}^{\ast}$ meson by using the the QCD sum rules form factors have been investigated. It is found that the SUSY effects are characteristically prominent to that of the SM values for these observables. For instance, in SUSY I and SUSY II, the forward-backward asymmetry does not cross zero which is mainly due to the same sign of the $C_{7}^{eff}$ and $C_{9}^{eff}$ Wilson coefficients. Similarly in SUSY SO(10) GUT models due to the complex nature of the new Wilson coefficients -- corresponding to the new operators arising due to the contribution of neutral Higgs bosons (NHBs) -- the above mentioned observables are sizably affected. Therefore the analysis of said observables in charmed semileptonic $B$ meson decays can put some stringent constraints on the parameter space of SUSY variants and can serve as a windowpane to look beyond the SM.
0906.2936
Michael Strickland
Jens O. Andersen, Michael Strickland, and Nan Su
Three-loop HTL Free Energy for QED
23 pages, 10 figures; v3 - typos corrected, additional discussions of systematics added; corresponds with published version
Phys.Rev.D80:085015,2009
10.1103/PhysRevD.80.085015
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the free energy of a hot gas of electrons and photons to three loops using the hard-thermal-loop perturbation theory reorganization of finite-temperature perturbation theory. We calculate the free energy through three loops by expanding in a power series in m_D/T, m_f/T, and e^2, where m_D and m_f are thermal masses and e is the coupling constant. We demonstrate that the hard-thermal-loop perturbation reorganization improves the convergence of the successive approximations to the QED free energy at large coupling, e ~ 2. The reorganization is gauge invariant by construction, and due to cancellation among various contributions, we obtain a completely analytic result for the resummed thermodynamic potential at three loops. Finally, we compare our result with similar calculations that use the Phi-derivable approach.
[ { "created": "Tue, 16 Jun 2009 13:59:05 GMT", "version": "v1" }, { "created": "Tue, 7 Jul 2009 11:34:44 GMT", "version": "v2" }, { "created": "Wed, 14 Oct 2009 20:17:11 GMT", "version": "v3" } ]
2009-10-29
[ [ "Andersen", "Jens O.", "" ], [ "Strickland", "Michael", "" ], [ "Su", "Nan", "" ] ]
We calculate the free energy of a hot gas of electrons and photons to three loops using the hard-thermal-loop perturbation theory reorganization of finite-temperature perturbation theory. We calculate the free energy through three loops by expanding in a power series in m_D/T, m_f/T, and e^2, where m_D and m_f are thermal masses and e is the coupling constant. We demonstrate that the hard-thermal-loop perturbation reorganization improves the convergence of the successive approximations to the QED free energy at large coupling, e ~ 2. The reorganization is gauge invariant by construction, and due to cancellation among various contributions, we obtain a completely analytic result for the resummed thermodynamic potential at three loops. Finally, we compare our result with similar calculations that use the Phi-derivable approach.
2204.05962
Matthew Kirk
Andreas Crivellin, Matthew Kirk, Teppei Kitahara and Federico Mescia
Large $t\to cZ$ as a Sign of Vector-Like Quarks in Light of the $W$ Mass
8 pages, 2 figures + supplemental material. v2: Accepted to PRD, discussion of future lepton colliders added, units corrected in eq II.9, further references added
Phys. Rev. D 106, L031704 (2022)
10.1103/PhysRevD.106.L031704
PSI-PR-22-09, ZU-TH-12/22, KEK-TH-2411
hep-ph hep-ex hep-th
http://creativecommons.org/licenses/by/4.0/
The rare flavour changing top quark decay $t\to cZ$ is a clear sign of new physics and experimentally very interesting due to the huge number of top quarks produced at the LHC. However, there are few (viable) models which can generate a sizable branching ratio for $t\to cZ$ -- in fact vector-like quarks seem to be the only realistic option. In this paper, we investigate all three representations (under the Standard Model gauge group) of vector-like quarks ($U$, $Q_1$ and $Q_7$) that can generate a sizable branching ratio for $t\to cZ$ without violating bounds from $B$ physics. Importantly, these are exactly the three vector-like quarks which can lead to a sizable positive shift in the prediction for $W$ mass, via the couplings to the top quark also needed for a sizable Br($t\to cZ$). Calculating and using the one-loop matching of vector-like quarks on the Standard Model Effective Field Theory, we find that Br($t\to cZ$) can be of the order of $10^{-6}$, $10^{-5}$ and $10^{-4}$ for $U$, $Q_1$ and $Q_7$, respectively and that in all three cases the large $W$ mass measurement can be accommodated.
[ { "created": "Tue, 12 Apr 2022 17:24:34 GMT", "version": "v1" }, { "created": "Fri, 12 Aug 2022 13:31:53 GMT", "version": "v2" } ]
2022-08-18
[ [ "Crivellin", "Andreas", "" ], [ "Kirk", "Matthew", "" ], [ "Kitahara", "Teppei", "" ], [ "Mescia", "Federico", "" ] ]
The rare flavour changing top quark decay $t\to cZ$ is a clear sign of new physics and experimentally very interesting due to the huge number of top quarks produced at the LHC. However, there are few (viable) models which can generate a sizable branching ratio for $t\to cZ$ -- in fact vector-like quarks seem to be the only realistic option. In this paper, we investigate all three representations (under the Standard Model gauge group) of vector-like quarks ($U$, $Q_1$ and $Q_7$) that can generate a sizable branching ratio for $t\to cZ$ without violating bounds from $B$ physics. Importantly, these are exactly the three vector-like quarks which can lead to a sizable positive shift in the prediction for $W$ mass, via the couplings to the top quark also needed for a sizable Br($t\to cZ$). Calculating and using the one-loop matching of vector-like quarks on the Standard Model Effective Field Theory, we find that Br($t\to cZ$) can be of the order of $10^{-6}$, $10^{-5}$ and $10^{-4}$ for $U$, $Q_1$ and $Q_7$, respectively and that in all three cases the large $W$ mass measurement can be accommodated.
hep-ph/9910441
Richard Easther
Richard Easther (Brown U.) and Matthew Parry (Imperial College)
Gravity, Parametric Resonance and Chaotic Inflation
16 pages, uses epsf to import postscript figures (minor changes - typos fixed, extra reference added and data analysis slightly expanded)
Phys.Rev. D62 (2000) 103503
10.1103/PhysRevD.62.103503
BROWN-HET-1152 Imperial/TP/99-0/004
hep-ph astro-ph gr-qc
null
We investigate the possibility that nonlinear gravitational effects influence the preheating era after inflation. Our work is based on numerical solutions of the inhomogeneous Einstein field equations, and is free of perturbative approximations. The one restriction we impose is to limit the inhomogeneity to a single spatial direction. We compare our results to perturbative calculations and to solutions of the nonlinear field equations in a rigid (unperturbed) spacetime, in order to isolate gravitational phenomena. We consider two types of initial conditions: where only one mode of the field perturbation has a non-zero initial amplitude, and where all the modes begin with a non-zero amplitude. Here we focus on preheating following inflation driven by a scalar field with a quartic potential. We confirm the broad picture of preheating obtained from the nonlinear field equations in a rigid background, but gravitational effects have a measurable impact on the dynamics for both sets of initial data. The rigid spacetime results predict that the amplitude of a single initially excited mode drops rapidly after resonance ends, whereas in the relativistic case the amplitude is roughly constant. With all modes initially excited, the longest modes in the simulation grow much more rapidly in the relativistic calculation than with a rigid background. However, we see no evidence for the sort of gravitational collapse associated with the formation of primordial black holes. The numerical codes described here are easily extended to more complicated resonant models, which we will examine in the future.
[ { "created": "Fri, 22 Oct 1999 20:35:58 GMT", "version": "v1" }, { "created": "Sat, 23 Oct 1999 18:03:56 GMT", "version": "v2" }, { "created": "Tue, 25 Jul 2000 01:40:31 GMT", "version": "v3" } ]
2009-10-31
[ [ "Easther", "Richard", "", "Brown U." ], [ "Parry", "Matthew", "", "Imperial College" ] ]
We investigate the possibility that nonlinear gravitational effects influence the preheating era after inflation. Our work is based on numerical solutions of the inhomogeneous Einstein field equations, and is free of perturbative approximations. The one restriction we impose is to limit the inhomogeneity to a single spatial direction. We compare our results to perturbative calculations and to solutions of the nonlinear field equations in a rigid (unperturbed) spacetime, in order to isolate gravitational phenomena. We consider two types of initial conditions: where only one mode of the field perturbation has a non-zero initial amplitude, and where all the modes begin with a non-zero amplitude. Here we focus on preheating following inflation driven by a scalar field with a quartic potential. We confirm the broad picture of preheating obtained from the nonlinear field equations in a rigid background, but gravitational effects have a measurable impact on the dynamics for both sets of initial data. The rigid spacetime results predict that the amplitude of a single initially excited mode drops rapidly after resonance ends, whereas in the relativistic case the amplitude is roughly constant. With all modes initially excited, the longest modes in the simulation grow much more rapidly in the relativistic calculation than with a rigid background. However, we see no evidence for the sort of gravitational collapse associated with the formation of primordial black holes. The numerical codes described here are easily extended to more complicated resonant models, which we will examine in the future.
hep-ph/9710370
Robert D. Pisarski
Robert D. Pisarski
Nonabelian Debye screening, tsunami waves, and worldline fermions
16 pages, LaTeX, requires crckapb.sty. To appear in the proceedings of the International School of Astrophysics ``D. Chalonge'', Erice, Italy, Sept. 4-15, 1997; also based on a talk given at the RIKEN BNL Workshop on ``Non-equilibrium many body dynamics'', Upton, N.Y., Sept. 23-25, 1997
null
null
null
hep-ph
null
I give a pedagogical review of the derivation for the effective lagrangian for nonabelian Debye screening, or hard thermal loops. Following Kelly, Liu, Lucchesi, and Manuel, I give the simplest derivation possible, using classical kinetic theory. The result is valid not just for a thermal, but for an arbitrary initial distributions. I use this to study the evolution, at short times, of a gluonic ``tsunami wave''. I also suggest how classical kinetic theory may arise at one loop order. Using the wordline representation of the one loop effective action, I follow D'Hoker and Gagn\'{e} to replace the Wilson line by an integral over worldline fermions. A bilinear of these worldline fermions naturally defines a nonabelian charge, whose equation of motion is Wong's equation.
[ { "created": "Wed, 15 Oct 1997 20:22:33 GMT", "version": "v1" } ]
2007-05-23
[ [ "Pisarski", "Robert D.", "" ] ]
I give a pedagogical review of the derivation for the effective lagrangian for nonabelian Debye screening, or hard thermal loops. Following Kelly, Liu, Lucchesi, and Manuel, I give the simplest derivation possible, using classical kinetic theory. The result is valid not just for a thermal, but for an arbitrary initial distributions. I use this to study the evolution, at short times, of a gluonic ``tsunami wave''. I also suggest how classical kinetic theory may arise at one loop order. Using the wordline representation of the one loop effective action, I follow D'Hoker and Gagn\'{e} to replace the Wilson line by an integral over worldline fermions. A bilinear of these worldline fermions naturally defines a nonabelian charge, whose equation of motion is Wong's equation.
1112.3112
Zhi-zhong Xing
Zhi-zhong Xing, He Zhang, Shun Zhou
Impacts of the Higgs mass on vacuum stability, running fermion masses and two-body Higgs decays
RevTex 14 pages, 4 figures; the treatment of vacuum stability improved, references updated
null
10.1103/PhysRevD.86.013013
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The latest results of the ATLAS and CMS experiments indicate 116 GeV \lesssim M_H \lesssim 131 GeV and 115 GeV \lesssim M_H \lesssim 127 GeV, respectively, for the mass of the Higgs boson in the standard model (SM) at the 95% confidence level. In particular, both experiments point to a preferred narrow mass range M_H \simeq (124 ... 126) GeV. We examine the impact of this preliminary result of M_H on the SM vacuum stability by using the two-loop renormalization-group equations (RGEs), and arrive at the cutoff scale \Lambda_VS \sim 4 \times 10^{12} GeV (for M_H = 125 GeV, M_t = 172.9 GeV and \alpha_s(M_Z) = 0.1184) where the absolute stability of the SM vacuum is lost and some kind of new physics might take effect. We update the values of running lepton and quark masses at some typical energy scales, including the ones characterized by M_H, 1 TeV and \Lambda_VS, with the help of the two-loop RGEs. The branching ratios of some important two-body Higgs decay modes, such as H \to b\bar{b}, H \to \tau^+ \tau^-, H\to \gamma\gamma, H\to W^+ W^- and H \to Z Z, are also recalculated by inputting the values of relevant particle masses at M_H.
[ { "created": "Wed, 14 Dec 2011 04:12:15 GMT", "version": "v1" }, { "created": "Tue, 15 May 2012 09:23:30 GMT", "version": "v2" } ]
2015-06-03
[ [ "Xing", "Zhi-zhong", "" ], [ "Zhang", "He", "" ], [ "Zhou", "Shun", "" ] ]
The latest results of the ATLAS and CMS experiments indicate 116 GeV \lesssim M_H \lesssim 131 GeV and 115 GeV \lesssim M_H \lesssim 127 GeV, respectively, for the mass of the Higgs boson in the standard model (SM) at the 95% confidence level. In particular, both experiments point to a preferred narrow mass range M_H \simeq (124 ... 126) GeV. We examine the impact of this preliminary result of M_H on the SM vacuum stability by using the two-loop renormalization-group equations (RGEs), and arrive at the cutoff scale \Lambda_VS \sim 4 \times 10^{12} GeV (for M_H = 125 GeV, M_t = 172.9 GeV and \alpha_s(M_Z) = 0.1184) where the absolute stability of the SM vacuum is lost and some kind of new physics might take effect. We update the values of running lepton and quark masses at some typical energy scales, including the ones characterized by M_H, 1 TeV and \Lambda_VS, with the help of the two-loop RGEs. The branching ratios of some important two-body Higgs decay modes, such as H \to b\bar{b}, H \to \tau^+ \tau^-, H\to \gamma\gamma, H\to W^+ W^- and H \to Z Z, are also recalculated by inputting the values of relevant particle masses at M_H.
hep-ph/0212276
Peter Tandy
M. Bhagwat, M. A. Pichowsky and P. C. Tandy (Kent State University, USA)
Confinement Phenomenology in the Bethe-Salpeter Equation
Submitted for publication; 10.5x2-column pages, REVTEX 4, 3 postscript files making 3 figs
Phys.Rev. D67 (2003) 054019
10.1103/PhysRevD.67.054019
null
hep-ph nucl-th
null
We consider the solution of the Bethe-Salpeter equation in Euclidean metric for a qbar-q vector meson in the circumstance where the dressed quark propagators have time-like complex conjugate mass poles. This approximates features encountered in recent QCD modeling via the Dyson-Schwinger equations; the absence of real mass poles simulates quark confinement. The analytic continuation in the total momentum necessary to reach the mass shell for a meson sufficiently heavier than 1 GeV leads to the quark poles being within the integration domain for two variables in the standard approach. Through Feynman integral techniques, we show how the analytic continuation can be implemented in a way suitable for a practical numerical solution. We show that the would-be qbar-q width to the meson generated from one quark pole is exactly cancelled by the effect of the conjugate partner pole; the meson mass remains real and there is no spurious qbar-q production threshold. The ladder kernel we employ is consistent with one-loop perturbative QCD and has a two-parameter infrared structure found to be successful in recent studies of the light SU(3) meson sector.
[ { "created": "Wed, 18 Dec 2002 22:36:22 GMT", "version": "v1" } ]
2009-11-07
[ [ "Bhagwat", "M.", "", "Kent State University,\n USA" ], [ "Pichowsky", "M. A.", "", "Kent State University,\n USA" ], [ "Tandy", "P. C.", "", "Kent State University,\n USA" ] ]
We consider the solution of the Bethe-Salpeter equation in Euclidean metric for a qbar-q vector meson in the circumstance where the dressed quark propagators have time-like complex conjugate mass poles. This approximates features encountered in recent QCD modeling via the Dyson-Schwinger equations; the absence of real mass poles simulates quark confinement. The analytic continuation in the total momentum necessary to reach the mass shell for a meson sufficiently heavier than 1 GeV leads to the quark poles being within the integration domain for two variables in the standard approach. Through Feynman integral techniques, we show how the analytic continuation can be implemented in a way suitable for a practical numerical solution. We show that the would-be qbar-q width to the meson generated from one quark pole is exactly cancelled by the effect of the conjugate partner pole; the meson mass remains real and there is no spurious qbar-q production threshold. The ladder kernel we employ is consistent with one-loop perturbative QCD and has a two-parameter infrared structure found to be successful in recent studies of the light SU(3) meson sector.
1707.00914
Umberto D'Alesio
Umberto D'Alesio, Francesco Murgia, Cristian Pisano
Testing the universality of the Collins function in pion-jet production at RHIC
10 pages, 5 figures (10 plots); v2: discussion on jet kT dependence of the SSAs extended and one plot on the corresponding unpolarized cross section added (Fig. 3, right panel); few comments on factorization breaking effects and on the universality issue of the Collins function added; three references added; results unchanged; matches the published version
Phys.Lett. B773 (2017) 300-306
10.1016/j.physletb.2017.08.023
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
By adopting a generalised parton model approach at leading order in QCD, including spin and intrinsic parton motion effects, we study the Collins azimuthal asymmetries for pions within a large-$p_T$ jet produced at mid-rapidity in polarised hadronic collisions. Using available information on the quark transversity distributions and the pion Collins functions, as extracted from semi-inclusive deeply inelastic scattering and $e^+e^-\to h_1 h_2\, X$ processes, we compute estimates for the Collins asymmetries in kinematical configurations presently investigated at RHIC by the STAR Collaboration. Collins-like asymmetries, involving linearly polarised gluons, are also considered. Our predictions, compared against available preliminary data, show a very good agreement, even if some discrepancies, to be further scrutinized both theoretically and experimentally, appear in the transverse momentum dependence of the Collins asymmetry. These results are in favour of the predicted universality of the Collins function and of a mild, if any, evolution with the hard scale of the asymmetries.
[ { "created": "Tue, 4 Jul 2017 11:16:20 GMT", "version": "v1" }, { "created": "Wed, 18 Oct 2017 08:54:07 GMT", "version": "v2" } ]
2017-10-19
[ [ "D'Alesio", "Umberto", "" ], [ "Murgia", "Francesco", "" ], [ "Pisano", "Cristian", "" ] ]
By adopting a generalised parton model approach at leading order in QCD, including spin and intrinsic parton motion effects, we study the Collins azimuthal asymmetries for pions within a large-$p_T$ jet produced at mid-rapidity in polarised hadronic collisions. Using available information on the quark transversity distributions and the pion Collins functions, as extracted from semi-inclusive deeply inelastic scattering and $e^+e^-\to h_1 h_2\, X$ processes, we compute estimates for the Collins asymmetries in kinematical configurations presently investigated at RHIC by the STAR Collaboration. Collins-like asymmetries, involving linearly polarised gluons, are also considered. Our predictions, compared against available preliminary data, show a very good agreement, even if some discrepancies, to be further scrutinized both theoretically and experimentally, appear in the transverse momentum dependence of the Collins asymmetry. These results are in favour of the predicted universality of the Collins function and of a mild, if any, evolution with the hard scale of the asymmetries.
2211.04806
Ernesto Arganda
Ernesto Arganda, Andres D. Perez, Martin de los Rios, Rosa Mar\'ia Sand\'a Seoane
Machine-Learned Exclusion Limits without Binning
24 pages, 8 figures, 3 tables, 1 appendix (version published in EPJC). MLL+KDE code available from https://github.com/AndresDanielPerez/2211.04806-ML-Likelihood-with-KDE
null
null
IFT-UAM/CSIC-22-134
hep-ph cs.LG hep-ex physics.data-an stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Machine-Learned Likelihoods (MLL) combines machine-learning classification techniques with likelihood-based inference tests to estimate the experimental sensitivity of high-dimensional data sets. We extend the MLL method by including Kernel Density Estimators (KDE) to avoid binning the classifier output to extract the resulting one-dimensional signal and background probability density functions. We first test our method on toy models generated with multivariate Gaussian distributions, where the true probability distribution functions are known. Later, we apply the method to two cases of interest at the LHC: a search for exotic Higgs bosons, and a $Z'$ boson decaying into lepton pairs. In contrast to physical-based quantities, the typical fluctuations of the ML outputs give non-smooth probability distributions for pure-signal and pure-background samples. The non-smoothness is propagated into the density estimation due to the good performance and flexibility of the KDE method. We study its impact on the final significance computation, and we compare the results using the average of several independent ML output realizations, which allows us to obtain smoother distributions. We conclude that the significance estimation turns out to be not sensible to this issue.
[ { "created": "Wed, 9 Nov 2022 11:04:50 GMT", "version": "v1" }, { "created": "Fri, 15 Dec 2023 11:40:58 GMT", "version": "v2" } ]
2023-12-18
[ [ "Arganda", "Ernesto", "" ], [ "Perez", "Andres D.", "" ], [ "Rios", "Martin de los", "" ], [ "Seoane", "Rosa María Sandá", "" ] ]
Machine-Learned Likelihoods (MLL) combines machine-learning classification techniques with likelihood-based inference tests to estimate the experimental sensitivity of high-dimensional data sets. We extend the MLL method by including Kernel Density Estimators (KDE) to avoid binning the classifier output to extract the resulting one-dimensional signal and background probability density functions. We first test our method on toy models generated with multivariate Gaussian distributions, where the true probability distribution functions are known. Later, we apply the method to two cases of interest at the LHC: a search for exotic Higgs bosons, and a $Z'$ boson decaying into lepton pairs. In contrast to physical-based quantities, the typical fluctuations of the ML outputs give non-smooth probability distributions for pure-signal and pure-background samples. The non-smoothness is propagated into the density estimation due to the good performance and flexibility of the KDE method. We study its impact on the final significance computation, and we compare the results using the average of several independent ML output realizations, which allows us to obtain smoother distributions. We conclude that the significance estimation turns out to be not sensible to this issue.
1812.06235
Thomas W. Kephart
Bradley L. Rachlin and Thomas W. Kephart
A Gauged Flavor Model of Quarks and Leptons
23 pages, 2 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Beyond Standard Model physics frequently connects flavor symmetry with a discrete group. If the discrete symmetry arises spontaneously from a gauge theory, one can maintain compatibility with quantum gravity and avoid anomalies. We provide an example of such a model with the Standard Model gauge group extended to $SU(3)_C \times SU(2)_L \times U(1)_Y \times SU(2)_{T'} $ where the binary tetrahedral flavor group $T'$ is embedded in $SU(2)_{T'}$. Quark and lepton masses and mixing angles are fit to data, where lepton mixing angles are shifted from tribimaximal values by the addition of scalar VEVs to agree with the experimental data.
[ { "created": "Sat, 15 Dec 2018 05:27:10 GMT", "version": "v1" } ]
2018-12-18
[ [ "Rachlin", "Bradley L.", "" ], [ "Kephart", "Thomas W.", "" ] ]
Beyond Standard Model physics frequently connects flavor symmetry with a discrete group. If the discrete symmetry arises spontaneously from a gauge theory, one can maintain compatibility with quantum gravity and avoid anomalies. We provide an example of such a model with the Standard Model gauge group extended to $SU(3)_C \times SU(2)_L \times U(1)_Y \times SU(2)_{T'} $ where the binary tetrahedral flavor group $T'$ is embedded in $SU(2)_{T'}$. Quark and lepton masses and mixing angles are fit to data, where lepton mixing angles are shifted from tribimaximal values by the addition of scalar VEVs to agree with the experimental data.
0911.4668
Anosh Joseph
Anosh Joseph, Mark Trodden
Vortex Scattering and Intercommuting Cosmic Strings on a Noncommutative Spacetime
18 pages, 2 figures
null
10.1103/PhysRevD.81.043536
SU-4252-900
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the scattering of noncommutative vortices, based on the noncommutative field theory developed in [Phys. Rev. D 75, 045009 (2007)], as a way to understand the interaction of cosmic strings. In the center-of-mass frame, the effects of noncommutativity vanish, and therefore the reconnection of cosmic strings occurs in an identical manner to the commutative case. However, when scattering occurs in a frame other than the center-of-mass frame, strings still reconnect but the well known 90-degree scattering no longer need correspond to the head on collision of the strings, due to the breakdown of Lorentz invariance in the underlying noncommutative field theory.
[ { "created": "Tue, 24 Nov 2009 16:30:16 GMT", "version": "v1" } ]
2015-05-14
[ [ "Joseph", "Anosh", "" ], [ "Trodden", "Mark", "" ] ]
We study the scattering of noncommutative vortices, based on the noncommutative field theory developed in [Phys. Rev. D 75, 045009 (2007)], as a way to understand the interaction of cosmic strings. In the center-of-mass frame, the effects of noncommutativity vanish, and therefore the reconnection of cosmic strings occurs in an identical manner to the commutative case. However, when scattering occurs in a frame other than the center-of-mass frame, strings still reconnect but the well known 90-degree scattering no longer need correspond to the head on collision of the strings, due to the breakdown of Lorentz invariance in the underlying noncommutative field theory.
2005.13687
Robinson Longas
Alexandra Gaviria, Robinson Longas, Andr\'es Rivera
Lepton dark matter portal in the inert Zee model
14 pages, 5 figures
null
10.1142/S0217751X20501900
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The inert Zee model is an extension of the Zee model for neutrino masses. This new model explains the dark matter relic abundance, generates a one-loop neutrino masses and forbids tree-level Higgs-mediated flavor changing neutral currents. Although the dark matter phenomenology of the model is similar to that of the inert doublet model, the presence of new vector-like fermions opens the lepton portal as a new dark matter annihilation channel. We study the impact of such a new portal in the low mass regime and show the parameter space allowed by direct and indirect searches of dark matter. Remarkably, we show that the region for $m_{H^0} \lesssim$ 70 GeV is recovered for $\lambda_L \lesssim 10^{-3}$. We also show that future experiments like LZ and DARWIN could test a large region of the parameter space of the model.
[ { "created": "Wed, 27 May 2020 22:27:11 GMT", "version": "v1" }, { "created": "Wed, 17 Feb 2021 00:38:42 GMT", "version": "v2" } ]
2021-02-18
[ [ "Gaviria", "Alexandra", "" ], [ "Longas", "Robinson", "" ], [ "Rivera", "Andrés", "" ] ]
The inert Zee model is an extension of the Zee model for neutrino masses. This new model explains the dark matter relic abundance, generates a one-loop neutrino masses and forbids tree-level Higgs-mediated flavor changing neutral currents. Although the dark matter phenomenology of the model is similar to that of the inert doublet model, the presence of new vector-like fermions opens the lepton portal as a new dark matter annihilation channel. We study the impact of such a new portal in the low mass regime and show the parameter space allowed by direct and indirect searches of dark matter. Remarkably, we show that the region for $m_{H^0} \lesssim$ 70 GeV is recovered for $\lambda_L \lesssim 10^{-3}$. We also show that future experiments like LZ and DARWIN could test a large region of the parameter space of the model.
1112.6261
Sven Bjarke Gudnason
Roberto Auzzi, Amit Giveon, Sven Bjarke Gudnason
Flavor of quiver-like realizations of effective supersymmetry
LaTeX, 17 pages, 3 figures. V2: reference added
JHEP 1202:069,2012
10.1007/JHEP02(2012)069
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a class of supersymmetric models which address the flavor puzzle and have an inverted hierarchy of sfermions. Their construction involves quiver-like models with link fields in generic representations. The magnitude of Standard-Model parameters is obtained naturally and a relatively heavy Higgs boson is allowed without fine tuning. Collider signatures of such models are possibly within the reach of LHC in the near future.
[ { "created": "Thu, 29 Dec 2011 09:55:41 GMT", "version": "v1" }, { "created": "Tue, 31 Jan 2012 15:11:26 GMT", "version": "v2" } ]
2012-03-02
[ [ "Auzzi", "Roberto", "" ], [ "Giveon", "Amit", "" ], [ "Gudnason", "Sven Bjarke", "" ] ]
We present a class of supersymmetric models which address the flavor puzzle and have an inverted hierarchy of sfermions. Their construction involves quiver-like models with link fields in generic representations. The magnitude of Standard-Model parameters is obtained naturally and a relatively heavy Higgs boson is allowed without fine tuning. Collider signatures of such models are possibly within the reach of LHC in the near future.
hep-ph/0608284
Harry Lipkin J
Harry J. Lipkin
CP violation difference in $B^o$ and $B^\pm$ decays explained No tree-penguin interference in $B^+ \to K^+\pi^o$
10 pages
null
null
WIS/14/06-SEPT-DPP,TAUP 2834/06,ANL-HEP-PR-06-63
hep-ph
null
A new experimental analysis of $B\to K\pi$ decays provides finite experimental values for the contributions from interference terms between the dominant penguin amplitude and the color-favored and color-suppressed tree amplitudes. These results can explain the puzzling failure to see CP violation in $B^\pm\to K\pi$ decays. Tree-penguin interference contributions are commonly believed to be the source of the observed direct CP violation in $B^o\to K^\pm\pi^\mp$ decays. The data show that the color-favored and color-suppressed tree contributions interfere destructively in $B^\pm\to K^\pm\pi^o$ decays and nearly cancel. This suprising cancellation is not predicted by present theory. There is also no prediction for any difference produced by changing the flavor of the spectator quark. Isospin and Pauli effects that change with spectator quark flavor are examined and show using group theory and the color-spun SU(6) algebra how they produce both the near cancellation and the dependence on spectator quark flavor. The standard $B\to K\pi$ analysis which treats tree-penguin interference only in first order has three parameters overdetermined by four experimental branching ratios. Previous analyses confirmed the model but with large errors leaving the values of tree-penguin interference contributions less that two standard deviations from zero. The new analysis finds interference contributions well above the errors.
[ { "created": "Fri, 25 Aug 2006 16:22:33 GMT", "version": "v1" }, { "created": "Wed, 6 Sep 2006 07:23:26 GMT", "version": "v2" }, { "created": "Mon, 25 Sep 2006 17:30:17 GMT", "version": "v3" } ]
2007-05-23
[ [ "Lipkin", "Harry J.", "" ] ]
A new experimental analysis of $B\to K\pi$ decays provides finite experimental values for the contributions from interference terms between the dominant penguin amplitude and the color-favored and color-suppressed tree amplitudes. These results can explain the puzzling failure to see CP violation in $B^\pm\to K\pi$ decays. Tree-penguin interference contributions are commonly believed to be the source of the observed direct CP violation in $B^o\to K^\pm\pi^\mp$ decays. The data show that the color-favored and color-suppressed tree contributions interfere destructively in $B^\pm\to K^\pm\pi^o$ decays and nearly cancel. This suprising cancellation is not predicted by present theory. There is also no prediction for any difference produced by changing the flavor of the spectator quark. Isospin and Pauli effects that change with spectator quark flavor are examined and show using group theory and the color-spun SU(6) algebra how they produce both the near cancellation and the dependence on spectator quark flavor. The standard $B\to K\pi$ analysis which treats tree-penguin interference only in first order has three parameters overdetermined by four experimental branching ratios. Previous analyses confirmed the model but with large errors leaving the values of tree-penguin interference contributions less that two standard deviations from zero. The new analysis finds interference contributions well above the errors.
2211.05240
Qiang Li
Dawei Fu, Alim Ruzi, Meng Lu, and Qiang Li
New methods to achieve meson, muon and gamma light sources through asymmetric electron positron collisions
Published in Int.J.Mod.Phys.A 38 (2023) 04n05, 2350033
null
10.1142/S0217751X23500331
null
hep-ph hep-ex nucl-ex physics.acc-ph
http://creativecommons.org/licenses/by/4.0/
We propose methods to produce energetic meson beams such as charged and neutral Kaons, which are boosted to be collimated and with relatively long life time. The first type of methods is based on asymmetric electron positron collisions with a center of mass energy of, e.g., 1020 MeV, and Kaons can be produced at a rate of $10^{4-5}/s$. The electron and positron beams are either asymmetric in energy, e.g., 10 GeV electron beam with 26 MeV positron beam, or asymmetric in space, e.g., 10 GeV electron and positron beams collisions separated with a angle around 0.05 radius. Such proposals should be able to be achieved with a reasonable budget. The other type of method is relying on TeV positron on target experiment, where Kaon beams can be achieved at around $10^{7}$ per bunch crossing. Such Kaon beams are clean with small contamination, and can have great physics potential on, e.g., hyperon searches through Kaon nuclei collision, Kaon rare decay measurement, and Kaon proton or Kaon lepton collisions. The same technique with very asymmetric electron positron collisions can also be extended to other final states such as pions and tau leptons.
[ { "created": "Wed, 9 Nov 2022 22:22:36 GMT", "version": "v1" }, { "created": "Sun, 13 Nov 2022 12:06:42 GMT", "version": "v2" }, { "created": "Thu, 17 Nov 2022 07:57:43 GMT", "version": "v3" }, { "created": "Mon, 6 Mar 2023 13:39:42 GMT", "version": "v4" }, { "cre...
2023-05-10
[ [ "Fu", "Dawei", "" ], [ "Ruzi", "Alim", "" ], [ "Lu", "Meng", "" ], [ "Li", "Qiang", "" ] ]
We propose methods to produce energetic meson beams such as charged and neutral Kaons, which are boosted to be collimated and with relatively long life time. The first type of methods is based on asymmetric electron positron collisions with a center of mass energy of, e.g., 1020 MeV, and Kaons can be produced at a rate of $10^{4-5}/s$. The electron and positron beams are either asymmetric in energy, e.g., 10 GeV electron beam with 26 MeV positron beam, or asymmetric in space, e.g., 10 GeV electron and positron beams collisions separated with a angle around 0.05 radius. Such proposals should be able to be achieved with a reasonable budget. The other type of method is relying on TeV positron on target experiment, where Kaon beams can be achieved at around $10^{7}$ per bunch crossing. Such Kaon beams are clean with small contamination, and can have great physics potential on, e.g., hyperon searches through Kaon nuclei collision, Kaon rare decay measurement, and Kaon proton or Kaon lepton collisions. The same technique with very asymmetric electron positron collisions can also be extended to other final states such as pions and tau leptons.
1104.1894
Bo-Qiang Ma
Xiao-Gang He, Bo-Qiang Ma
The CDF dijet excess from intrinsic quarks
4 latex pages, 1 figure. Version for journal publication
Eur. Phys. J. A 47 (2011) 152
10.1140/epja/i2011-11152-x
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The CDF collaboration reported an excess in the production of two jets in association with a $W$. We discuss constraints on possible new particle state interpretations of this excess. The fact of no statistically significant deviation from the SM expectation for {$Z$+dijet} events in CDF data disfavors the new particle explanation. We show that the nucleon intrinsic strange quarks provide an important contribution to the $W$ boson production in association with a single top quark production. Such {$W$+t} single top quark production can contribute to the CDF {$W$+dijet} excess, thus the nucleon intrinsic quarks can provide a possible explanation to the CDF excess in {$W$+dijet} but not in {$Z$+dijet} events.
[ { "created": "Mon, 11 Apr 2011 09:53:06 GMT", "version": "v1" }, { "created": "Thu, 1 Dec 2011 06:49:11 GMT", "version": "v2" } ]
2011-12-12
[ [ "He", "Xiao-Gang", "" ], [ "Ma", "Bo-Qiang", "" ] ]
The CDF collaboration reported an excess in the production of two jets in association with a $W$. We discuss constraints on possible new particle state interpretations of this excess. The fact of no statistically significant deviation from the SM expectation for {$Z$+dijet} events in CDF data disfavors the new particle explanation. We show that the nucleon intrinsic strange quarks provide an important contribution to the $W$ boson production in association with a single top quark production. Such {$W$+t} single top quark production can contribute to the CDF {$W$+dijet} excess, thus the nucleon intrinsic quarks can provide a possible explanation to the CDF excess in {$W$+dijet} but not in {$Z$+dijet} events.
1902.00307
Ji Xu
Yu-Sheng Liu, Wei Wang, Ji Xu, Qi-An Zhang, Jian-Hui Zhang, Shuai Zhao and Yong Zhao
Matching Quasi Generalized Parton Distributions in the RI/MOM scheme
13 pages, 2 figures
Phys. Rev. D 100, 034006 (2019)
10.1103/PhysRevD.100.034006
MIT-CTP/5074, INT-PUB-19-004
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Within the framework of large momentum effective theory (LaMET), genenaralized parton distributions (GPDs) can be extracted from lattice calculations of quasi-GPDs through a perturbative matching relation, up to power corrections that are suppressed by the hadron momentum. In this paper, we focus on isovector quark GPDs, including the unpolarized, longitudinally and transversely polarized cases, and present the one-loop matching that connects the quasi-GPDs renormalized in a regularization-independent momentum subtraction (RI/MOM) scheme to the GPDs in MS scheme. We find that the matching coefficient is independent of the momentum transfer squared. As a consequence, the matching for the quasi-GPD with zero skewness is the same as that for the quasi-PDF. Our results provide a crucial input for the determination of quark GPDs from lattice QCD using LaMET.
[ { "created": "Fri, 1 Feb 2019 12:46:38 GMT", "version": "v1" }, { "created": "Wed, 31 Jul 2019 19:30:18 GMT", "version": "v2" } ]
2019-08-14
[ [ "Liu", "Yu-Sheng", "" ], [ "Wang", "Wei", "" ], [ "Xu", "Ji", "" ], [ "Zhang", "Qi-An", "" ], [ "Zhang", "Jian-Hui", "" ], [ "Zhao", "Shuai", "" ], [ "Zhao", "Yong", "" ] ]
Within the framework of large momentum effective theory (LaMET), genenaralized parton distributions (GPDs) can be extracted from lattice calculations of quasi-GPDs through a perturbative matching relation, up to power corrections that are suppressed by the hadron momentum. In this paper, we focus on isovector quark GPDs, including the unpolarized, longitudinally and transversely polarized cases, and present the one-loop matching that connects the quasi-GPDs renormalized in a regularization-independent momentum subtraction (RI/MOM) scheme to the GPDs in MS scheme. We find that the matching coefficient is independent of the momentum transfer squared. As a consequence, the matching for the quasi-GPD with zero skewness is the same as that for the quasi-PDF. Our results provide a crucial input for the determination of quark GPDs from lattice QCD using LaMET.
1512.08796
Abdesslam Arhrib
Abdesslam Arhrib, C\'eline B{\oe}hm, Ernest Ma and Tzu-Chiang Yuan
Radiative Model of Neutrino Mass with Neutrino Interacting MeV Dark Matter
34 pages, 4 figures, references added, journal version published in JCAP
null
10.1088/1475-7516/2016/04/049
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the radiative generation of neutrino mass through the interactions of neutrinos with MeV dark matter. We construct a realistic renormalizable model with one scalar doublet and one complex singlet together with three light singlet Majorana fermions, all transforming under a dark U(1) symmetry which breaks softly to Z_2. We study in detail the scalar sector which supports this specific scenario and its rich phenomenology.
[ { "created": "Tue, 29 Dec 2015 21:12:56 GMT", "version": "v1" }, { "created": "Mon, 11 Jan 2016 15:23:20 GMT", "version": "v2" }, { "created": "Thu, 14 Jul 2016 12:04:07 GMT", "version": "v3" } ]
2016-07-15
[ [ "Arhrib", "Abdesslam", "" ], [ "Bœhm", "Céline", "" ], [ "Ma", "Ernest", "" ], [ "Yuan", "Tzu-Chiang", "" ] ]
We consider the radiative generation of neutrino mass through the interactions of neutrinos with MeV dark matter. We construct a realistic renormalizable model with one scalar doublet and one complex singlet together with three light singlet Majorana fermions, all transforming under a dark U(1) symmetry which breaks softly to Z_2. We study in detail the scalar sector which supports this specific scenario and its rich phenomenology.
2110.03228
Kai Murai
Tomohiro Fujita, Kyohei Mukaida, Kai Murai, and Hiromasa Nakatsuka
SU($N$)-natural inflation
8 pages, 6 figures
Phys. Rev. D 105, 103519 (2022)
10.1103/PhysRevD.105.103519
KEK-TH-2349
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study SU($N$) gauge fields that couple to the inflaton through the Chern-Simons term. We provide a general procedure to construct homogeneous, isotropic, and attractor solutions of the gauge fields during inflation. The gauge fields develop various VEVs corresponding to different spontaneous symmetry breaking patterns of SU($N$) where embedded SU($2$) subgroups are broken with the spatial rotation SO($3$) symmetry. As specific examples, we construct the stable solutions for $N = 3$ and $4$. We also numerically solve the gauge field dynamics and confirm that our analytic solutions are complete and attractor. It is straightforward to apply our procedure to the other simple Lie groups.
[ { "created": "Thu, 7 Oct 2021 07:25:00 GMT", "version": "v1" }, { "created": "Thu, 19 May 2022 04:22:50 GMT", "version": "v2" } ]
2022-05-20
[ [ "Fujita", "Tomohiro", "" ], [ "Mukaida", "Kyohei", "" ], [ "Murai", "Kai", "" ], [ "Nakatsuka", "Hiromasa", "" ] ]
We study SU($N$) gauge fields that couple to the inflaton through the Chern-Simons term. We provide a general procedure to construct homogeneous, isotropic, and attractor solutions of the gauge fields during inflation. The gauge fields develop various VEVs corresponding to different spontaneous symmetry breaking patterns of SU($N$) where embedded SU($2$) subgroups are broken with the spatial rotation SO($3$) symmetry. As specific examples, we construct the stable solutions for $N = 3$ and $4$. We also numerically solve the gauge field dynamics and confirm that our analytic solutions are complete and attractor. It is straightforward to apply our procedure to the other simple Lie groups.
hep-ph/0701167
Hendrik van Hees
Hendrik van Hees and Ralf Rapp
Interpretation of Recent SPS Dilepton Data
To appear in the proceedings of the 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter 2006) v2: references added, minor typos corrected
J.Phys.G34:S1051,2007
10.1088/0954-3899/34/8/S154
null
hep-ph nucl-ex nucl-th
null
We summarize our current theoretical understanding of in-medium properties of the electromagnetic current correlator in view of recent dimuon data from the NA60 experiment in In(158 AGeV)-In collisions at the CERN-SPS. We discuss the sensitivity of the results to space-time evolution models for the hot and dense partonic and hadronic medium created in relativistic heavy-ion collisions and the contributions from different sources to the dilepton-excess spectra.
[ { "created": "Sat, 20 Jan 2007 02:03:35 GMT", "version": "v1" }, { "created": "Mon, 16 Apr 2007 17:15:30 GMT", "version": "v2" } ]
2008-11-26
[ [ "van Hees", "Hendrik", "" ], [ "Rapp", "Ralf", "" ] ]
We summarize our current theoretical understanding of in-medium properties of the electromagnetic current correlator in view of recent dimuon data from the NA60 experiment in In(158 AGeV)-In collisions at the CERN-SPS. We discuss the sensitivity of the results to space-time evolution models for the hot and dense partonic and hadronic medium created in relativistic heavy-ion collisions and the contributions from different sources to the dilepton-excess spectra.
2303.07505
Selcuk Bilmis
T.M.Aliev, S.Bilmis, M.Savci
The study of weak decays induced by $\frac{1}{2}^+ \to \frac{3}{2}^-$ transition in light-cone sum rules
null
Phys.Lett.B 847 (2023) 138287
10.1016/j.physletb.2023.138287
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this study, we analyzed the weak decays induced by $J^P = \frac{1}{2}^{+} \to \frac{3}{2}^{-} $ transitions within the light-cone sum rules. Specifically, semileptonic decays of the bottom baryons into the P-wave baryons $\Lambda_b \to \Lambda_c(2625) \ell \nu_l$ and $\Xi_b \to \Xi_c(2815) \ell \nu_l$ as well as nonleptonic $\Lambda_b \to \Lambda_c(2625) \pi (\rho)$ and $\Xi_b \to \Xi_c(2815) \pi (\rho)$ decays are investigated. The form factors for the considered transitions are obtained within the sum rules method. With the calculated form factors, the decay widths of the processes are determined. Up to now, only the decay width for $\Lambda_b^0 \to \Lambda_c^+ \mu^- \nu_\mu$ has been measured among the considered decays, and we observe that our finding is quite compatible with the measurement. We also compare our results with the predictions of other approaches.
[ { "created": "Mon, 13 Mar 2023 22:30:00 GMT", "version": "v1" }, { "created": "Thu, 16 Nov 2023 13:07:02 GMT", "version": "v2" } ]
2023-11-17
[ [ "Aliev", "T. M.", "" ], [ "Bilmis", "S.", "" ], [ "Savci", "M.", "" ] ]
In this study, we analyzed the weak decays induced by $J^P = \frac{1}{2}^{+} \to \frac{3}{2}^{-} $ transitions within the light-cone sum rules. Specifically, semileptonic decays of the bottom baryons into the P-wave baryons $\Lambda_b \to \Lambda_c(2625) \ell \nu_l$ and $\Xi_b \to \Xi_c(2815) \ell \nu_l$ as well as nonleptonic $\Lambda_b \to \Lambda_c(2625) \pi (\rho)$ and $\Xi_b \to \Xi_c(2815) \pi (\rho)$ decays are investigated. The form factors for the considered transitions are obtained within the sum rules method. With the calculated form factors, the decay widths of the processes are determined. Up to now, only the decay width for $\Lambda_b^0 \to \Lambda_c^+ \mu^- \nu_\mu$ has been measured among the considered decays, and we observe that our finding is quite compatible with the measurement. We also compare our results with the predictions of other approaches.
2007.01765
Dimitrios K. Papoulias
O. G. Miranda, D. K. Papoulias, M. T\'ortola, J. W. F. Valle
XENON1T signal from transition neutrino magnetic moments
10 pages, 3 figures, 1 table. V2: Fig.1 updated, references added, matches published version
Phys.Lett. B 808 (2020) 135685
10.1016/j.physletb.2020.135685
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The recent puzzling results of the XENON1T collaboration at few keV electronic recoils could be due to the scattering of solar neutrinos endowed with finite Majorana transition magnetic moments (TMMs). Within such general formalism, we find that the observed excess in the XENON1T data agrees well with this interpretation. The required TMM strengths lie within the limits set by current experiments, such as Borexino, specially when one takes into account a possible tritium contamination.
[ { "created": "Fri, 3 Jul 2020 15:41:28 GMT", "version": "v1" }, { "created": "Fri, 14 Aug 2020 21:15:49 GMT", "version": "v2" } ]
2020-08-18
[ [ "Miranda", "O. G.", "" ], [ "Papoulias", "D. K.", "" ], [ "Tórtola", "M.", "" ], [ "Valle", "J. W. F.", "" ] ]
The recent puzzling results of the XENON1T collaboration at few keV electronic recoils could be due to the scattering of solar neutrinos endowed with finite Majorana transition magnetic moments (TMMs). Within such general formalism, we find that the observed excess in the XENON1T data agrees well with this interpretation. The required TMM strengths lie within the limits set by current experiments, such as Borexino, specially when one takes into account a possible tritium contamination.
hep-ph/9511223
Shoichi Midorikawa
M. Honda, T. Kajita, K. Kasahara, and S. Midorikawa
Atmospheric Neutrinos
8 pages, PTPTEX.sty, to appear in Proceedings of YKIS '95, From the Standard Model to Grand Unified Theories
Prog.Theor.Phys.Suppl.123:483-490,1996
10.1143/PTPS.123.483
null
hep-ph
null
The atmospheric neutrino-flux is calculated over the wide energy range from 1 GeV to 3,000 GeV for the study of neutrino-physics using the data from underground neutrino-detectors. The uncertainty of atmospheric neutrino-flux is also discussed. A brief comment is made to interpret the anomaly in terms of neutrino oscillations.
[ { "created": "Fri, 3 Nov 1995 07:16:24 GMT", "version": "v1" }, { "created": "Sat, 4 Nov 1995 04:18:11 GMT", "version": "v2" }, { "created": "Mon, 6 Nov 1995 08:44:49 GMT", "version": "v3" } ]
2011-04-15
[ [ "Honda", "M.", "" ], [ "Kajita", "T.", "" ], [ "Kasahara", "K.", "" ], [ "Midorikawa", "S.", "" ] ]
The atmospheric neutrino-flux is calculated over the wide energy range from 1 GeV to 3,000 GeV for the study of neutrino-physics using the data from underground neutrino-detectors. The uncertainty of atmospheric neutrino-flux is also discussed. A brief comment is made to interpret the anomaly in terms of neutrino oscillations.
1111.0603
Leonard Gamberg
Leonard Gamberg, Daniel Boer, Bernhard Musch, Alexei Prokudin
Semi-Inclusive Deep Inelastic Scattering and Bessel-Weighted Asymmetries
7 pages, 1 figure, to appear in PACSpin2011 (Cairns, 20-24 June, 2011) conference proceedings (AIP)
null
10.1063/1.3667306
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the cross section in Fourier space, conjugate to the outgoing hadron's transverse momentum, where convolutions of transverse momentum dependent parton distribution functions and fragmentation functions become simple products. Individual asymmetric terms in the cross section can be projected out by means of a generalized set of weights involving Bessel functions. Advantages of employing these Bessel weights are that they suppress (divergent) contributions from high transverse momentum and that soft factors cancel in (Bessel-) weighted asymmetries. Also, the resulting compact expressions immediately connect to previous work on evolution equations for transverse momentum dependent parton distribution and fragmentation functions and to quantities accessible in lattice QCD. Bessel-weighted asymmetries are thus model independent observables that augment the description and our understanding of correlations of spin and momentum in nucleon structure.
[ { "created": "Wed, 2 Nov 2011 18:49:18 GMT", "version": "v1" } ]
2015-06-03
[ [ "Gamberg", "Leonard", "" ], [ "Boer", "Daniel", "" ], [ "Musch", "Bernhard", "" ], [ "Prokudin", "Alexei", "" ] ]
We consider the cross section in Fourier space, conjugate to the outgoing hadron's transverse momentum, where convolutions of transverse momentum dependent parton distribution functions and fragmentation functions become simple products. Individual asymmetric terms in the cross section can be projected out by means of a generalized set of weights involving Bessel functions. Advantages of employing these Bessel weights are that they suppress (divergent) contributions from high transverse momentum and that soft factors cancel in (Bessel-) weighted asymmetries. Also, the resulting compact expressions immediately connect to previous work on evolution equations for transverse momentum dependent parton distribution and fragmentation functions and to quantities accessible in lattice QCD. Bessel-weighted asymmetries are thus model independent observables that augment the description and our understanding of correlations of spin and momentum in nucleon structure.
1703.04754
Hubert Spiesberger
G. Kramer and H. Spiesberger
Study of heavy meson production in p-Pb collisions at $\sqrt{S}$=5.02 TeV in the general-mass variable-flavour-number scheme
20 pages, extended discussion, agrees with published version in Nucl.Phys.B
null
null
DESY 17-040, MITP/17-016
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study inclusive charm and bottom production, for both D and B mesons, in p-Pb collisions at the LHC. Numerical results for p_T-differential production cross sections are obtained at next-to-leading-order in the general-mass variable-flavor-number scheme. We compare our results with recent data from ALICE, LHCb and CMS at a center-of-mass energy of 5 TeV and find good agreement. A comparison with p-p cross sections does not reveal the presence of nuclear initial-state interaction effects that could be expected to become visible as deviations of the ratio of p-Pb and p-p cross sections from one.
[ { "created": "Tue, 14 Mar 2017 22:13:14 GMT", "version": "v1" }, { "created": "Tue, 31 Oct 2017 10:05:24 GMT", "version": "v2" } ]
2017-11-01
[ [ "Kramer", "G.", "" ], [ "Spiesberger", "H.", "" ] ]
We study inclusive charm and bottom production, for both D and B mesons, in p-Pb collisions at the LHC. Numerical results for p_T-differential production cross sections are obtained at next-to-leading-order in the general-mass variable-flavor-number scheme. We compare our results with recent data from ALICE, LHCb and CMS at a center-of-mass energy of 5 TeV and find good agreement. A comparison with p-p cross sections does not reveal the presence of nuclear initial-state interaction effects that could be expected to become visible as deviations of the ratio of p-Pb and p-p cross sections from one.
0910.3102
Christine T. H. Davies
C. T. H. Davies, C. McNeile, K. Y. Wong, E. Follana, R. Horgan, K. Hornbostel, G. P. Lepage, J. Shigemitsu, H. Trottier
Precise charm to strange mass ratio and light quark masses from full lattice QCD
4 pages, 2 figures. Version accepted by Physical Review Letters. Changes include modifying the title, using the MILC value for m_s/m_l which changes slightly the resulting up and down quark masses and their average, adding some references and making other small adjustments to the text for space reasons.
Phys.Rev.Lett.104:132003,2010
10.1103/PhysRevLett.104.132003
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
By using a single formalism to handle charm, strange and light valence quarks in full lattice QCD for the first time, we are able to determine ratios of quark masses to 1%. For $m_c/m_s$ we obtain 11.85(16), an order of magnitude more precise than the current PDG average. Combined with 1% determinations of the charm quark mass now possible this gives $\bar{m}_s(2{\rm GeV}) =$ 92.4(1.5) MeV. The MILC result for $m_s/m_l = 27.2(3) $ yields $\bar{m}_l(2{\rm GeV})$ = 3.40(7) MeV for the average of $u$ and $d$ quark masses.
[ { "created": "Fri, 16 Oct 2009 12:30:32 GMT", "version": "v1" }, { "created": "Thu, 11 Mar 2010 10:36:43 GMT", "version": "v2" } ]
2010-04-06
[ [ "Davies", "C. T. H.", "" ], [ "McNeile", "C.", "" ], [ "Wong", "K. Y.", "" ], [ "Follana", "E.", "" ], [ "Horgan", "R.", "" ], [ "Hornbostel", "K.", "" ], [ "Lepage", "G. P.", "" ], [ "Shigemitsu", ...
By using a single formalism to handle charm, strange and light valence quarks in full lattice QCD for the first time, we are able to determine ratios of quark masses to 1%. For $m_c/m_s$ we obtain 11.85(16), an order of magnitude more precise than the current PDG average. Combined with 1% determinations of the charm quark mass now possible this gives $\bar{m}_s(2{\rm GeV}) =$ 92.4(1.5) MeV. The MILC result for $m_s/m_l = 27.2(3) $ yields $\bar{m}_l(2{\rm GeV})$ = 3.40(7) MeV for the average of $u$ and $d$ quark masses.