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hep-ph/9909252
Fedor Simkovic
Amand Faessler and Fedor Simkovic
Test of Physics beyond the Standard Model in Nuclei
20 pages including 3 figures, Latex, Talk presented at NANP99 (Non-Accelerator New Physics, Dubna, July 1999), to be published in Phys. Atom. Nucl
Phys.Atom.Nucl.63:1165-1176,2000; Yad.Fiz.63N7:1240-1251,2000
10.1134/1.855762
null
hep-ph
null
The modern theories of Grand Unification (GUT) and supersymmetric (SUSY) extensions of standard model (SM) suppose that the conservation laws of the SM may be violated to some small degree. The nuclei are well-suited as a laboratory to test fundamental symmetries and fundamental interactions like lepton flavor (LF) and lepton number (LN) conservation. A prominent role between experiments looking for LF and total LN violation play yet not observed processes of neutrinoless double beta decay. The GUT's and SUSY models offer a variety of mechanisms which allow this process to occur. They are based on mixing of Majorana neutrinos and/or R-parity violation hypothesis. Although the neutrinoless double beta decay has not been seen it is possible to extract from the lower limits of the lifetime upper limits for the effective electron Majorana neutrino mass, effective right handed weak interaction parameters, the effective Majoron coupling constant, R-parity violating SUSY parameters etc. In this work the limits on the LN violating parameters extracted from current neutrinoless double beta decay experiments are listed. Studies in respect to future neutrinoless double beta decay experimental projects are also presented.
[ { "created": "Sat, 4 Sep 1999 17:29:53 GMT", "version": "v1" } ]
2011-04-15
[ [ "Faessler", "Amand", "" ], [ "Simkovic", "Fedor", "" ] ]
The modern theories of Grand Unification (GUT) and supersymmetric (SUSY) extensions of standard model (SM) suppose that the conservation laws of the SM may be violated to some small degree. The nuclei are well-suited as a laboratory to test fundamental symmetries and fundamental interactions like lepton flavor (LF) and lepton number (LN) conservation. A prominent role between experiments looking for LF and total LN violation play yet not observed processes of neutrinoless double beta decay. The GUT's and SUSY models offer a variety of mechanisms which allow this process to occur. They are based on mixing of Majorana neutrinos and/or R-parity violation hypothesis. Although the neutrinoless double beta decay has not been seen it is possible to extract from the lower limits of the lifetime upper limits for the effective electron Majorana neutrino mass, effective right handed weak interaction parameters, the effective Majoron coupling constant, R-parity violating SUSY parameters etc. In this work the limits on the LN violating parameters extracted from current neutrinoless double beta decay experiments are listed. Studies in respect to future neutrinoless double beta decay experimental projects are also presented.
hep-ph/0206256
Cristiano B. Mariotto
C. Brenner Mariotto, M.B. Gay Ducati (Rio Grande do Sul U.), G. Ingelman (Uppsala U.)
Improved mapping of ccbar onto charmonium states
To appear in the proceedings of VIII International Workshop on Hadron Physics (Hadrons 2002), Bento Goncalves, Brazil, 14 - 19 April 2002
null
null
null
hep-ph
null
We discuss the relative rates of different charmonium states and introduce an improved model for mapping the continuous ccbar mass spectrum on the physical charmonium resonances.
[ { "created": "Tue, 25 Jun 2002 17:46:12 GMT", "version": "v1" } ]
2007-05-23
[ [ "Mariotto", "C. Brenner", "", "Rio Grande do Sul U." ], [ "Ducati", "M. B. Gay", "", "Rio Grande do Sul U." ], [ "Ingelman", "G.", "", "Uppsala U." ] ]
We discuss the relative rates of different charmonium states and introduce an improved model for mapping the continuous ccbar mass spectrum on the physical charmonium resonances.
2108.04570
Kadir Ocalan
Kadir Ocalan
Impact of lepton $p_{T}$ threshold on the charge asymmetry predictions for the inclusive $W$ boson production in $pp$ collisions at 13 TeV
11 pages, 7 figures
Chinese Phys. C 45 (2021) 083103
10.1088/1674-1137/ac03ad
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
This paper presents the impact of lepton transverse momentum $p^{l}_{T}$ threshold on the $W$ boson charge asymmetry predictions in perturbative QCD for the inclusive $W^{\pm}+X \rightarrow l^{\pm} \nu +X$ production in proton-proton ($pp$) collisions. The predictions are obtained with various low-$p^{l}_{T}$ thresholds $p^{l}_{T} >$ 20, 25, 30, and 40 GeV in a fiducial region encompassing both central and forward detector acceptances in terms of the lepton pseudorapidty 0 $\leq \eta_{l} \leq$ 4.5. The predicted distributions for the lepton charge asymmetry, which is defined by means of the $\eta_{l}$ ($A_{\eta_{l}}$), at next-to-next-to-leading order (NNLO) accuracy are compared with the CMS and LHCb data at 8 TeV center-of-mass collision energy. The 8 TeV predictions are observed to reproduce the data fairly well within the quoted uncertainties. The 13 TeV predictions by using various $p^{l}_{T}$ thresholds are reported for the $A_{\eta_{l}}$ and also the charge asymmetries that are defined in terms of the differential cross sections in bins of the $W$ boson rapidity $y_{W}$ ($A_{y_{W}}$) and transverse momentum $p^{W}_{T}$ ($A_{p^{W}_{T}}$). The NNLO predictions for the $A_{\eta_{l}}$, $A_{y_{W}}$, and $A_{p^{W}_{T}}$ distributions are assessed to be in close correlation with the $p^{l}_{T}$ value. The $A_{\eta_{l}}$ and $A_{y_{W}}$ distributions are particularly shown to be more correlated at a higher $p^{l}_{T}$ threshold. The $A_{p^{W}_{T}}$ distributions are also reported from the merged predictions with improved accuracy by the inclusion of next-to-next-to-next-to-leading logarithm (N$^{3}$LL) corrections, i.e., at NNLO+N$^{3}$LL. The predicted distributions from various $p^{l}_{T}$ thresholds represent also a finer probe to provide more constraints on the ratio of $u$ and $d$ quark distribution functions in the parton momentum fraction range $10^{-4} < x < 1$.
[ { "created": "Tue, 10 Aug 2021 10:43:27 GMT", "version": "v1" } ]
2021-08-11
[ [ "Ocalan", "Kadir", "" ] ]
This paper presents the impact of lepton transverse momentum $p^{l}_{T}$ threshold on the $W$ boson charge asymmetry predictions in perturbative QCD for the inclusive $W^{\pm}+X \rightarrow l^{\pm} \nu +X$ production in proton-proton ($pp$) collisions. The predictions are obtained with various low-$p^{l}_{T}$ thresholds $p^{l}_{T} >$ 20, 25, 30, and 40 GeV in a fiducial region encompassing both central and forward detector acceptances in terms of the lepton pseudorapidty 0 $\leq \eta_{l} \leq$ 4.5. The predicted distributions for the lepton charge asymmetry, which is defined by means of the $\eta_{l}$ ($A_{\eta_{l}}$), at next-to-next-to-leading order (NNLO) accuracy are compared with the CMS and LHCb data at 8 TeV center-of-mass collision energy. The 8 TeV predictions are observed to reproduce the data fairly well within the quoted uncertainties. The 13 TeV predictions by using various $p^{l}_{T}$ thresholds are reported for the $A_{\eta_{l}}$ and also the charge asymmetries that are defined in terms of the differential cross sections in bins of the $W$ boson rapidity $y_{W}$ ($A_{y_{W}}$) and transverse momentum $p^{W}_{T}$ ($A_{p^{W}_{T}}$). The NNLO predictions for the $A_{\eta_{l}}$, $A_{y_{W}}$, and $A_{p^{W}_{T}}$ distributions are assessed to be in close correlation with the $p^{l}_{T}$ value. The $A_{\eta_{l}}$ and $A_{y_{W}}$ distributions are particularly shown to be more correlated at a higher $p^{l}_{T}$ threshold. The $A_{p^{W}_{T}}$ distributions are also reported from the merged predictions with improved accuracy by the inclusion of next-to-next-to-next-to-leading logarithm (N$^{3}$LL) corrections, i.e., at NNLO+N$^{3}$LL. The predicted distributions from various $p^{l}_{T}$ thresholds represent also a finer probe to provide more constraints on the ratio of $u$ and $d$ quark distribution functions in the parton momentum fraction range $10^{-4} < x < 1$.
0903.1723
Alexander Lenz
Alexander Lenz, Meinulf G\"ockeler, Thomas Kaltenbrunner, Nikolaus Warkentin
The Nucleon Distribution Amplitudes and their application to nucleon form factors and the $N \to \Delta$ transition at intermediate values of $Q^2$
28 pages, 28 figures, version accepted by PRD
Phys.Rev.D79:093007,2009
10.1103/PhysRevD.79.093007
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compare a recent lattice determination of the nucleon distribution amplitudes with other approaches and models. We study the nucleon distribution amplitudes up to twist 6 in next-to leading conformal spin and we also investigate conformal d-wave contributions to the leading twist distribution amplitude. With the help of light-cone sum rules one can relate the distribution amplitudes to the form factors of the nucleon or the $ N \to \Delta$ transition at intermediate values of the momentum transfer. We compare our results with experimental data in the range 1 GeV$^2 \leq Q^2 \leq 10$ GeV$^2$. Keeping in mind that we are working only in LO QCD and NLO-QCD corrections might be sizeable we already obtain a surprisingly good agreement for the nucleon form factors $G_M^n$, $G_M^p$, $G_A^p$ and $G_T^p$ and for the $N \to \Delta$ transition form factor ratios $R_{EM}$ and $R_{SM}$.
[ { "created": "Tue, 10 Mar 2009 09:57:15 GMT", "version": "v1" }, { "created": "Fri, 24 Apr 2009 21:50:41 GMT", "version": "v2" } ]
2009-07-30
[ [ "Lenz", "Alexander", "" ], [ "Göckeler", "Meinulf", "" ], [ "Kaltenbrunner", "Thomas", "" ], [ "Warkentin", "Nikolaus", "" ] ]
We compare a recent lattice determination of the nucleon distribution amplitudes with other approaches and models. We study the nucleon distribution amplitudes up to twist 6 in next-to leading conformal spin and we also investigate conformal d-wave contributions to the leading twist distribution amplitude. With the help of light-cone sum rules one can relate the distribution amplitudes to the form factors of the nucleon or the $ N \to \Delta$ transition at intermediate values of the momentum transfer. We compare our results with experimental data in the range 1 GeV$^2 \leq Q^2 \leq 10$ GeV$^2$. Keeping in mind that we are working only in LO QCD and NLO-QCD corrections might be sizeable we already obtain a surprisingly good agreement for the nucleon form factors $G_M^n$, $G_M^p$, $G_A^p$ and $G_T^p$ and for the $N \to \Delta$ transition form factor ratios $R_{EM}$ and $R_{SM}$.
hep-ph/9408253
null
M. Carena and C.E.M. Wagner
Higgs and Supersymmetric Particle Signals at the Infrared Fixed Point of the Top Quark Mass
42 pages, 16 figures (not included), CERN-TH.7393/93
Nucl.Phys.B452:45-79,1995
10.1016/0550-3213(95)00341-O
null
hep-ph
null
We study the properties of the Higgs and supersymmetric particle spectrum associated with the infrared fixed point solution of the top quark mass in the MSSM. We concentrate on the possible detection of these particles, analysing the deviations from the Standard Model predictions for the leptonic and hadronic variables measured at LEP and for the decay rate $b\rightarrow s\gamma$. We consider the low and moderate $\tan \beta$ regime, and we study both, the cases of universal and non--universal soft supersymmetry breaking parameters at high energies. In the first case, for any given value of the top quark mass, the Higgs and sparticle spectra are completely determined as a function of two soft supersymmetry breaking parameters. In the case of non--universality, instead, the strong correlations between the sparticle masses are relaxed, allowing a richer structure for the precision data variables. We show, however, that the requirement that the low energy theory proceeds from a grand unified theory with a local symmetry group including $SU(5)$, strongly constrains the set of possible indirect experimental signatures. As a general feature, whenever a significant deviation from the Standard Model value of the precision data variables is predicted, a light sparticle, visible at LEP2, appears in the spectrum.
[ { "created": "Tue, 9 Aug 1994 03:23:57 GMT", "version": "v1" } ]
2008-11-26
[ [ "Carena", "M.", "" ], [ "Wagner", "C. E. M.", "" ] ]
We study the properties of the Higgs and supersymmetric particle spectrum associated with the infrared fixed point solution of the top quark mass in the MSSM. We concentrate on the possible detection of these particles, analysing the deviations from the Standard Model predictions for the leptonic and hadronic variables measured at LEP and for the decay rate $b\rightarrow s\gamma$. We consider the low and moderate $\tan \beta$ regime, and we study both, the cases of universal and non--universal soft supersymmetry breaking parameters at high energies. In the first case, for any given value of the top quark mass, the Higgs and sparticle spectra are completely determined as a function of two soft supersymmetry breaking parameters. In the case of non--universality, instead, the strong correlations between the sparticle masses are relaxed, allowing a richer structure for the precision data variables. We show, however, that the requirement that the low energy theory proceeds from a grand unified theory with a local symmetry group including $SU(5)$, strongly constrains the set of possible indirect experimental signatures. As a general feature, whenever a significant deviation from the Standard Model value of the precision data variables is predicted, a light sparticle, visible at LEP2, appears in the spectrum.
1307.2031
Hideko Nagahiro
Hideko Nagahiro and Atsushi Hosaka
Composite and elementary nature of a resonance in the sigma model
13 pages, 11 figures, 2 tables
Phys. Rev. C 88, 055203 (2013)
10.1103/PhysRevC.88.055203
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the mixing nature of the low-lying scalar resonance consisting of the pipi composite and the elementary particle within the sigma model. A method to disentangle the mixing is formulated in the scattering theory with the concept of the two-level problem. We investigate the composite and elementary components of the sigma meson by changing a mixing parameter. We also study the dependence of the results on model parameters such as the cut-off value and the mass of the elementary sigma meson.
[ { "created": "Mon, 8 Jul 2013 10:54:35 GMT", "version": "v1" } ]
2013-11-13
[ [ "Nagahiro", "Hideko", "" ], [ "Hosaka", "Atsushi", "" ] ]
We analyze the mixing nature of the low-lying scalar resonance consisting of the pipi composite and the elementary particle within the sigma model. A method to disentangle the mixing is formulated in the scattering theory with the concept of the two-level problem. We investigate the composite and elementary components of the sigma meson by changing a mixing parameter. We also study the dependence of the results on model parameters such as the cut-off value and the mass of the elementary sigma meson.
1203.4218
Filippo Sala
Riccardo Barbieri, Dario Buttazzo, Filippo Sala, David M. Straub
Flavour physics from an approximate U(2)^3 symmetry
29 pages, 5 figures
null
10.1007/JHEP07(2012)181
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The quark sector of the Standard Model exhibits an approximate U(2)^3 flavour symmetry. This symmetry, broken in specific directions dictated by minimality, can explain the success of the Cabibbo-Kobayashi-Maskawa picture of flavour mixing and CP violation, confirmed by the data so far, while allowing for observable deviations from it, as expected in most models of ElectroWeak Symmetry Breaking. Building on previous work in the specific context of supersymmetry, we analyze the expected effects and we quantify the current bounds in a general Effective Field Theory framework. As a further relevant example we then show how the U(2)^3 symmetry and its breaking can be implemented in a generic composite Higgs model and we make a first analysis of its peculiar consequences. We also discuss how some partial extension of U(2)^3 to the lepton sector can arise, both in general and in composite Higgs models. An optimistic though conceivable interpretation of the considerations developed in this paper gives reasons to think that new physics searches in the flavour sector may be about to explore an interesting realm of phenomena.
[ { "created": "Mon, 19 Mar 2012 19:55:14 GMT", "version": "v1" } ]
2017-08-23
[ [ "Barbieri", "Riccardo", "" ], [ "Buttazzo", "Dario", "" ], [ "Sala", "Filippo", "" ], [ "Straub", "David M.", "" ] ]
The quark sector of the Standard Model exhibits an approximate U(2)^3 flavour symmetry. This symmetry, broken in specific directions dictated by minimality, can explain the success of the Cabibbo-Kobayashi-Maskawa picture of flavour mixing and CP violation, confirmed by the data so far, while allowing for observable deviations from it, as expected in most models of ElectroWeak Symmetry Breaking. Building on previous work in the specific context of supersymmetry, we analyze the expected effects and we quantify the current bounds in a general Effective Field Theory framework. As a further relevant example we then show how the U(2)^3 symmetry and its breaking can be implemented in a generic composite Higgs model and we make a first analysis of its peculiar consequences. We also discuss how some partial extension of U(2)^3 to the lepton sector can arise, both in general and in composite Higgs models. An optimistic though conceivable interpretation of the considerations developed in this paper gives reasons to think that new physics searches in the flavour sector may be about to explore an interesting realm of phenomena.
1111.4401
Jos Van Doorsselaere
M. N. Chernodub, J. Van Doorsselaere, H. Verschelde
Electromagnetically superconducting phase of vacuum in strong magnetic field: structure of superconductor and superfluid vortex lattices in the ground state
13 pages, 11 figures
null
10.1103/PhysRevD.85.045002
null
hep-ph hep-lat hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently it was shown that vacuum in a background of strong enough magnetic field becomes an electromagnetic superconductor due to interplay between strong and electromagnetic forces. The superconducting ground state of the vacuum is associated with a spontaneous emergence of quark-antiquark condensates which carry quantum numbers of charged rho mesons. The rho-meson condensate is an inhomogeneous structure made of the so-called rho vortices, which are parallel to the magnetic field axis. The condensation of the charged rho mesons induces a (much weaker) superfluid-like condensate with quantum numbers of the neutral rho mesons. In this paper we show that the vortices in the superconducting condensate organize themselves in an equilateral triangular lattice similarly to an ordinary type-II superconductor. We show that each of these superconductor vortices is accompanied by three superfluid vortices and three superfluid antivortices made of the neutral rho meson condensate. The superconductor vortex overlaps with one of the superfluid vortices. The superposition of the superconducting and superfluid vortex lattices has a honeycomb pattern.
[ { "created": "Fri, 18 Nov 2011 15:47:34 GMT", "version": "v1" } ]
2013-05-30
[ [ "Chernodub", "M. N.", "" ], [ "Van Doorsselaere", "J.", "" ], [ "Verschelde", "H.", "" ] ]
Recently it was shown that vacuum in a background of strong enough magnetic field becomes an electromagnetic superconductor due to interplay between strong and electromagnetic forces. The superconducting ground state of the vacuum is associated with a spontaneous emergence of quark-antiquark condensates which carry quantum numbers of charged rho mesons. The rho-meson condensate is an inhomogeneous structure made of the so-called rho vortices, which are parallel to the magnetic field axis. The condensation of the charged rho mesons induces a (much weaker) superfluid-like condensate with quantum numbers of the neutral rho mesons. In this paper we show that the vortices in the superconducting condensate organize themselves in an equilateral triangular lattice similarly to an ordinary type-II superconductor. We show that each of these superconductor vortices is accompanied by three superfluid vortices and three superfluid antivortices made of the neutral rho meson condensate. The superconductor vortex overlaps with one of the superfluid vortices. The superposition of the superconducting and superfluid vortex lattices has a honeycomb pattern.
1408.5880
Jorge S. Diaz
Jorge S. Diaz
Tests of Lorentz symmetry in single beta decay
7 pages
Adv. High Energy Phys. 2014, 305298 (2014)
10.1155/2014/305298
KA-TP-23-2014
hep-ph hep-ex nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Low-energy experiments studying single beta decay can serve as sensitive probes of Lorentz invariance that can complement interferometric searches for deviations from this spacetime symmetry. Experimental signatures of a dimension-three operator for Lorentz violation that are unobservable in neutrino oscillations are described for the decay the polarized and unpolarized neutrons as well as for measurements of the spectral endpoint in beta decay.
[ { "created": "Mon, 25 Aug 2014 19:47:09 GMT", "version": "v1" } ]
2014-08-26
[ [ "Diaz", "Jorge S.", "" ] ]
Low-energy experiments studying single beta decay can serve as sensitive probes of Lorentz invariance that can complement interferometric searches for deviations from this spacetime symmetry. Experimental signatures of a dimension-three operator for Lorentz violation that are unobservable in neutrino oscillations are described for the decay the polarized and unpolarized neutrons as well as for measurements of the spectral endpoint in beta decay.
hep-ph/0308071
BingAn Li
Bing An Li
Invalid Ward-Takahashi identities and broken unitarity of the SM
18 pages
null
null
null
hep-ph
null
It is found that in the SM the Ward-Takahashi(WT) identities of the axial-vector currents and the charged vector currents of fermions are invalid after spontaneous symmetry breaking. The spin-0 components of Z and W fields are revealed from the invalidity of these WT identities. The masses of these spin-0 components are at $10^{14}$GeV. They are ghosts. Therefore, unitarity of the SM after spontaneous symmetry breaking is broken at $10^{14}$GeV.
[ { "created": "Wed, 6 Aug 2003 19:31:24 GMT", "version": "v1" } ]
2007-05-23
[ [ "Li", "Bing An", "" ] ]
It is found that in the SM the Ward-Takahashi(WT) identities of the axial-vector currents and the charged vector currents of fermions are invalid after spontaneous symmetry breaking. The spin-0 components of Z and W fields are revealed from the invalidity of these WT identities. The masses of these spin-0 components are at $10^{14}$GeV. They are ghosts. Therefore, unitarity of the SM after spontaneous symmetry breaking is broken at $10^{14}$GeV.
hep-ph/0612082
Brigitte Hiller
A.A. Osipov, B. Hiller, J. Moreira, A. H. Blin, J. da Providencia
Lowering the critical temperature with eight-quark interactions
4 pages, 2 figures
Phys.Lett.B646:91-94,2007
10.1016/j.physletb.2007.01.026
null
hep-ph
null
It is shown that eight-quark interactions, which are needed to stabilize the ground state of the combined three flavor Nambu -- Jona-Lasinio and 't Hooft Lagrangians, play also an important role in determining the critical temperature at which transitions occur from the dynamically broken chiral phase to the symmetric phase.
[ { "created": "Thu, 7 Dec 2006 11:14:23 GMT", "version": "v1" } ]
2008-11-26
[ [ "Osipov", "A. A.", "" ], [ "Hiller", "B.", "" ], [ "Moreira", "J.", "" ], [ "Blin", "A. H.", "" ], [ "da Providencia", "J.", "" ] ]
It is shown that eight-quark interactions, which are needed to stabilize the ground state of the combined three flavor Nambu -- Jona-Lasinio and 't Hooft Lagrangians, play also an important role in determining the critical temperature at which transitions occur from the dynamically broken chiral phase to the symmetric phase.
1112.4360
S. Weinzierl
Stefan M\"uller-Stach, Stefan Weinzierl and Raphael Zayadeh
A second-order differential equation for the two-loop sunrise graph with arbitrary masses
16 pages, version to be published
null
null
null
hep-ph math-ph math.AG math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive a second-order differential equation for the two-loop sunrise graph in two dimensions with arbitrary masses. The differential equation is obtained by viewing the Feynman integral as a period of a variation of a mixed Hodge structure, where the variation is with respect to the external momentum squared. The fibre is the complement of an elliptic curve. From the fact that the first cohomology group of this elliptic curve is two-dimensional we obtain a second-order differential equation. This is an improvement compared to the usual way of deriving differential equations: Integration-by-parts identities lead only to a coupled system of four first-order differential equations.
[ { "created": "Mon, 19 Dec 2011 15:15:14 GMT", "version": "v1" }, { "created": "Mon, 30 Apr 2012 05:53:16 GMT", "version": "v2" } ]
2012-05-01
[ [ "Müller-Stach", "Stefan", "" ], [ "Weinzierl", "Stefan", "" ], [ "Zayadeh", "Raphael", "" ] ]
We derive a second-order differential equation for the two-loop sunrise graph in two dimensions with arbitrary masses. The differential equation is obtained by viewing the Feynman integral as a period of a variation of a mixed Hodge structure, where the variation is with respect to the external momentum squared. The fibre is the complement of an elliptic curve. From the fact that the first cohomology group of this elliptic curve is two-dimensional we obtain a second-order differential equation. This is an improvement compared to the usual way of deriving differential equations: Integration-by-parts identities lead only to a coupled system of four first-order differential equations.
hep-ph/0311245
Robert N. Cahn
Robert N. Cahn and George H. Trilling
Experimental Limits on the Width of the Reported Theta(1540)+
3 pages, 1 figure, submitted to Physical Review D (RC)
Phys.Rev.D69:011501,2004
10.1103/PhysRevD.69.011501
LBNL-54065
hep-ph
null
Using data on K^+ collisions on xenon and deuterium we derive values and limits on the width of the reported Theta(1540)^+ exotic baryon resonance. The xenon experiment gives a width of 0.9\pm 0.3 MeV. The other experiments give upper limits in the range 1 - 4 MeV.
[ { "created": "Thu, 20 Nov 2003 01:12:41 GMT", "version": "v1" } ]
2008-11-26
[ [ "Cahn", "Robert N.", "" ], [ "Trilling", "George H.", "" ] ]
Using data on K^+ collisions on xenon and deuterium we derive values and limits on the width of the reported Theta(1540)^+ exotic baryon resonance. The xenon experiment gives a width of 0.9\pm 0.3 MeV. The other experiments give upper limits in the range 1 - 4 MeV.
hep-ph/0408078
Leonardo Campanelli
Leonardo Campanelli
Scattering of Dirac and Majorana Fermions off Domain Walls
6 pages, 1 figure, some typos corrected, one reference added, major revisions, title changed, version accepted for publication in Phys. Rev. D
Phys.Rev. D70 (2004) 116008
10.1103/PhysRevD.70.116008
null
hep-ph
null
We investigate the interaction of fermions having both Dirac and left-handed and right-handed Majorana mass terms with vacuum domain walls. By solving the equations of motion in thin-wall approximation, we calculate the reflection and transmission coefficients for the scattering of fermions off walls.
[ { "created": "Thu, 5 Aug 2004 16:51:27 GMT", "version": "v1" }, { "created": "Wed, 1 Dec 2004 14:52:32 GMT", "version": "v2" } ]
2009-11-10
[ [ "Campanelli", "Leonardo", "" ] ]
We investigate the interaction of fermions having both Dirac and left-handed and right-handed Majorana mass terms with vacuum domain walls. By solving the equations of motion in thin-wall approximation, we calculate the reflection and transmission coefficients for the scattering of fermions off walls.
hep-ph/9603274
Kuang-Ta Chao
Cong-feng Qiao, Han-Wen Huang, Kuang-Ta Chao (Peking University)
Possible retardation effects of quark confinement on the meson spectrum
14 pages in LaTex form
Phys.Rev. D54 (1996) 2273-2278
10.1103/PhysRevD.54.2273
PUTP-95-23
hep-ph
null
The reduced Bethe-Salpeter equation with scalar confinement and vector gluon exchange is applied to quark-antiquark bound states. The so called intrinsic flaw of Salpeter equation with static scalar confinement is investigated. The notorious problem of narrow level spacings is found to be remedied by taking into consideration the retardation effect of scalar confinement. Good fit for the mass spectrum of both heavy and light quarkomium states is then obtained.
[ { "created": "Tue, 12 Mar 1996 04:27:06 GMT", "version": "v1" } ]
2009-10-28
[ [ "Qiao", "Cong-feng", "", "Peking University" ], [ "Huang", "Han-Wen", "", "Peking University" ], [ "Chao", "Kuang-Ta", "", "Peking University" ] ]
The reduced Bethe-Salpeter equation with scalar confinement and vector gluon exchange is applied to quark-antiquark bound states. The so called intrinsic flaw of Salpeter equation with static scalar confinement is investigated. The notorious problem of narrow level spacings is found to be remedied by taking into consideration the retardation effect of scalar confinement. Good fit for the mass spectrum of both heavy and light quarkomium states is then obtained.
2202.12476
Subhojit Roy
Arindam Chatterjee, AseshKrishna Datta and Subhojit Roy
Electroweak Phase Transition in the $Z_3$-invariant NMSSM: Implications of LHC and Dark matter searches and prospects of detecting the gravitational waves
52 pages, 3 figures, 6 tables. published version, references added
JHEP06(2022)108
10.1007/JHEP06(2022)108
HRI-RECAPP-2022-001
hep-ph
http://creativecommons.org/publicdomain/zero/1.0/
We study in detail the viability and the patterns of a strong first-order electroweak phase transition as a prerequisite to electroweak baryogenesis in the framework of $Z_3$-invariant Next-to-Minimal Supersymmetric Standard Model (NMSSM), in the light of recent experimental results from the Higgs sector, dark matter (DM) searches and those from the searches of the lighter chargino and neutralinos at the Large Hadron Collider (LHC). For the latter, we undertake thorough recasts of the relevant, recent LHC analyses. With the help of a few benchmark scenarios, we demonstrate that while the LHC has started to eliminate regions of the parameter space with relatively small $\mu_\mathrm{eff}$, that favors the coveted strong first-order phase transition, rather steadily, there remains phenomenologically much involved and compatible regions of the same which are yet not sensitive to the current LHC analyses. It is further noted that such a region could also be compatible with all pertinent theoretical and experimental constraints. We then proceed to analyze the prospects of detecting the stochastic gravitational waves, which are expected to arise from such a phase transition, at various future/proposed experiments, within the mentioned theoretical framework and find them to be somewhat ambitious under the currently projected sensitivities of those experiments.
[ { "created": "Fri, 25 Feb 2022 03:15:44 GMT", "version": "v1" }, { "created": "Tue, 16 May 2023 15:39:54 GMT", "version": "v2" } ]
2023-05-17
[ [ "Chatterjee", "Arindam", "" ], [ "Datta", "AseshKrishna", "" ], [ "Roy", "Subhojit", "" ] ]
We study in detail the viability and the patterns of a strong first-order electroweak phase transition as a prerequisite to electroweak baryogenesis in the framework of $Z_3$-invariant Next-to-Minimal Supersymmetric Standard Model (NMSSM), in the light of recent experimental results from the Higgs sector, dark matter (DM) searches and those from the searches of the lighter chargino and neutralinos at the Large Hadron Collider (LHC). For the latter, we undertake thorough recasts of the relevant, recent LHC analyses. With the help of a few benchmark scenarios, we demonstrate that while the LHC has started to eliminate regions of the parameter space with relatively small $\mu_\mathrm{eff}$, that favors the coveted strong first-order phase transition, rather steadily, there remains phenomenologically much involved and compatible regions of the same which are yet not sensitive to the current LHC analyses. It is further noted that such a region could also be compatible with all pertinent theoretical and experimental constraints. We then proceed to analyze the prospects of detecting the stochastic gravitational waves, which are expected to arise from such a phase transition, at various future/proposed experiments, within the mentioned theoretical framework and find them to be somewhat ambitious under the currently projected sensitivities of those experiments.
1504.05813
Stefan Clementz
Mattias Blennow and Stefan Clementz
Asymmetric capture of Dirac dark matter by the Sun
22 pages, 5 figures, Version accepted for publication in JCAP. A discussion regarding the distribution of captured DM added. Figure 4 added under results. Minor corrections and references added
null
10.1088/1475-7516/2015/08/036
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Current problems with the solar model may be alleviated if a significant amount of dark matter from the galactic halo is captured in the Sun. We discuss the capture process in the case where the dark matter is a Dirac fermion and the background halo consists of equal amounts of dark matter and anti-dark matter. By considering the case where dark matter and anti-dark matter have different cross sections on solar nuclei as well as the case where the capture process is considered to be a Poisson process, we find that a significant asymmetry between the captured dark particles and anti-particles is possible even for an annihilation cross section in the range expected for thermal relic dark matter. Since the captured number of particles are competitive with asymmetric dark matter models in a large range of parameter space, one may expect solar physics to be altered by the capture of Dirac dark matter. It is thus possible that solutions to the solar composition problem may be searched for in these type of models.
[ { "created": "Wed, 22 Apr 2015 14:09:20 GMT", "version": "v1" }, { "created": "Wed, 19 Aug 2015 11:30:25 GMT", "version": "v2" } ]
2015-08-20
[ [ "Blennow", "Mattias", "" ], [ "Clementz", "Stefan", "" ] ]
Current problems with the solar model may be alleviated if a significant amount of dark matter from the galactic halo is captured in the Sun. We discuss the capture process in the case where the dark matter is a Dirac fermion and the background halo consists of equal amounts of dark matter and anti-dark matter. By considering the case where dark matter and anti-dark matter have different cross sections on solar nuclei as well as the case where the capture process is considered to be a Poisson process, we find that a significant asymmetry between the captured dark particles and anti-particles is possible even for an annihilation cross section in the range expected for thermal relic dark matter. Since the captured number of particles are competitive with asymmetric dark matter models in a large range of parameter space, one may expect solar physics to be altered by the capture of Dirac dark matter. It is thus possible that solutions to the solar composition problem may be searched for in these type of models.
hep-ph/9903358
Mark Wusthoff
K. Golec-Biernat, M. Wusthoff
Saturation in Diffractive Deep Inelastic Scattering
31 pages, 12 figures, replaced with the journal version. A missing factor 1/2 in eq.(39) inserted
Phys.Rev.D60:114023,1999
10.1103/PhysRevD.60.114023
DTP/99/20
hep-ph
null
We successfully describe the HERA-data on diffractive deep inelastic scattering using a saturation model which has been applied in our earlier analysis of the inclusive $ep$-scattering data. No further parameters are needed. Saturation already turned out to be essential in describing the transition from large to small values of $Q^2$ in inclusive scattering. It is even more important for diffractive processes and naturally leads to a constant ratio of the diffractive versus inclusive cross sections. We present an extensive discussion of our results as well as detailed comparison with data.
[ { "created": "Mon, 15 Mar 1999 18:59:26 GMT", "version": "v1" }, { "created": "Wed, 28 Feb 2001 17:08:25 GMT", "version": "v2" } ]
2008-11-26
[ [ "Golec-Biernat", "K.", "" ], [ "Wusthoff", "M.", "" ] ]
We successfully describe the HERA-data on diffractive deep inelastic scattering using a saturation model which has been applied in our earlier analysis of the inclusive $ep$-scattering data. No further parameters are needed. Saturation already turned out to be essential in describing the transition from large to small values of $Q^2$ in inclusive scattering. It is even more important for diffractive processes and naturally leads to a constant ratio of the diffractive versus inclusive cross sections. We present an extensive discussion of our results as well as detailed comparison with data.
2307.00628
Wen Yin
Kai Murai and Wen Yin
A Novel Probe of Supersymmetry in Light of Nanohertz Gravitational Waves
17pages, 1 figure, 1 table, comments are welcome
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A new era of exploring the early Universe may have begun with the recent strong evidence for the stochastic gravitational wave (GW) background from the data reported by NANOGrav, EPTA, PPTA, and CPTA. Inspired by this, we propose a new potential source of stochastic GWs in the minimal supersymmetric standard model (MSSM), which could be the theory at a very high energy scale. This source is the "axion" field in the Higgs multiplets when the Higgs field takes a large value along the D-flat direction in the early Universe, for example, during inflation. The axion motion triggers the instability of the standard model ${\rm U}(1)$ and/or ${\rm SU}(3)$ gauge fields, producing stochastic GWs during the inflation. This scenario can be seen as a simple UV completion of the commonly studied models where an axion spectator/inflaton is coupled to a hidden ${\rm U}(1)$ or ${\rm SU}(N)$ gauge field without matter fields. Thus the nanohertz GWs may be a sign of supersymmetry. Primordial magnetic field production is also argued. In addition, we point out the simple possibility that this axion within the MSSM drives inflation.
[ { "created": "Sun, 2 Jul 2023 17:53:01 GMT", "version": "v1" } ]
2023-07-04
[ [ "Murai", "Kai", "" ], [ "Yin", "Wen", "" ] ]
A new era of exploring the early Universe may have begun with the recent strong evidence for the stochastic gravitational wave (GW) background from the data reported by NANOGrav, EPTA, PPTA, and CPTA. Inspired by this, we propose a new potential source of stochastic GWs in the minimal supersymmetric standard model (MSSM), which could be the theory at a very high energy scale. This source is the "axion" field in the Higgs multiplets when the Higgs field takes a large value along the D-flat direction in the early Universe, for example, during inflation. The axion motion triggers the instability of the standard model ${\rm U}(1)$ and/or ${\rm SU}(3)$ gauge fields, producing stochastic GWs during the inflation. This scenario can be seen as a simple UV completion of the commonly studied models where an axion spectator/inflaton is coupled to a hidden ${\rm U}(1)$ or ${\rm SU}(N)$ gauge field without matter fields. Thus the nanohertz GWs may be a sign of supersymmetry. Primordial magnetic field production is also argued. In addition, we point out the simple possibility that this axion within the MSSM drives inflation.
1608.08575
Emanuele Roberto Nocera
Emanuele Nocera and Silvia Pisano
Summary of WG6: Spin Physics
10 pages, 5 figures, to appear in the proceedings of DIS2016
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The working group on Spin Physics at the XXIV International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS2016) witnessed a significant progress in the theoretical and experimental investigations aiming at unveiling the innermost structure of the proton. Results ranged from proton's one-dimensional representation to its multi-dimensional imaging. In this contribution, we summarize a selection of the topics discussed and of the results presented. For details, we refer to the individual contributions collected in the proceedings of this workshop.
[ { "created": "Tue, 30 Aug 2016 17:47:35 GMT", "version": "v1" } ]
2016-08-31
[ [ "Nocera", "Emanuele", "" ], [ "Pisano", "Silvia", "" ] ]
The working group on Spin Physics at the XXIV International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS2016) witnessed a significant progress in the theoretical and experimental investigations aiming at unveiling the innermost structure of the proton. Results ranged from proton's one-dimensional representation to its multi-dimensional imaging. In this contribution, we summarize a selection of the topics discussed and of the results presented. For details, we refer to the individual contributions collected in the proceedings of this workshop.
1907.10577
Peihong Gu
Pei-Hong Gu
Baryon asymmetry from left-right phase transition
6 pages
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend the standard model fermions by a mirror copy to realize a left-right symmetry. During a strongly first order phase transition of the spontaneous left-right symmetry breaking, the CP-violating reflections of the mirror fermions off the mirror Higgs bubbles can generate a mirror lepton asymmetry and an equal mirror baryon asymmetry. We then can obtain an ordinary baryon asymmetry through the mirror fermion decays where a dark matter scalar plays an essential role. Benefitted from a parity symmetry for solving the strong CP problem, the cosmic baryon asymmetry can be well described by the ordinary lepton mass matrices up to an overall factor. In this scenario, the Dirac CP phase in the Majorana neutrino mass matrix can provide a unique source for the required CP violation. Furthermore, the Higgs triplet for type-II seesaw as well as the first generation of mirror charged fermions can be allowed at the TeV scale.
[ { "created": "Wed, 24 Jul 2019 17:28:26 GMT", "version": "v1" } ]
2020-01-09
[ [ "Gu", "Pei-Hong", "" ] ]
We extend the standard model fermions by a mirror copy to realize a left-right symmetry. During a strongly first order phase transition of the spontaneous left-right symmetry breaking, the CP-violating reflections of the mirror fermions off the mirror Higgs bubbles can generate a mirror lepton asymmetry and an equal mirror baryon asymmetry. We then can obtain an ordinary baryon asymmetry through the mirror fermion decays where a dark matter scalar plays an essential role. Benefitted from a parity symmetry for solving the strong CP problem, the cosmic baryon asymmetry can be well described by the ordinary lepton mass matrices up to an overall factor. In this scenario, the Dirac CP phase in the Majorana neutrino mass matrix can provide a unique source for the required CP violation. Furthermore, the Higgs triplet for type-II seesaw as well as the first generation of mirror charged fermions can be allowed at the TeV scale.
hep-ph/9904241
Susanne Bielefeld
S. Bielefeld, J.Ihmels, and H.C. Pauli (MPI Kernphysik,Heidelberg)
On technically solving an effective QCD-Hamiltonian
9 pages, 24 eps-figures, macro svjour included
null
null
Heidelberg preprint MPIH-V11-1999
hep-ph
null
By their very nature, field-theoretical Hamiltonians are derived in momentum representation. To solve the corresponding integro-differential equations is more difficult than to solve the simpler differential equations in configuration space (`Schr\"odinger equation'). For the latter many different and very effective methods have been developed in the past. But rather than to Fourier-transform to configuration space - which is not always easy - the equations are solved here directly in momentum space, by using Gaussian quadratures. Special attention is given to the case where the potential in configuration space is linear and where the corresponding momentum-space kernel has an almost intractable 1/(\vec k - \vec k')^4 -singularity. Its regularization requires a certain technical effort, introducing suitable counter terms. The method is numerically reliable and fast, faster than other methods in the literature. It should be useful to and also applicable in other approaches, including phenomenological Schr\"odinger-type equations.
[ { "created": "Tue, 6 Apr 1999 13:31:26 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bielefeld", "S.", "", "MPI Kernphysik,Heidelberg" ], [ "Ihmels", "J.", "", "MPI Kernphysik,Heidelberg" ], [ "Pauli", "H. C.", "", "MPI Kernphysik,Heidelberg" ] ]
By their very nature, field-theoretical Hamiltonians are derived in momentum representation. To solve the corresponding integro-differential equations is more difficult than to solve the simpler differential equations in configuration space (`Schr\"odinger equation'). For the latter many different and very effective methods have been developed in the past. But rather than to Fourier-transform to configuration space - which is not always easy - the equations are solved here directly in momentum space, by using Gaussian quadratures. Special attention is given to the case where the potential in configuration space is linear and where the corresponding momentum-space kernel has an almost intractable 1/(\vec k - \vec k')^4 -singularity. Its regularization requires a certain technical effort, introducing suitable counter terms. The method is numerically reliable and fast, faster than other methods in the literature. It should be useful to and also applicable in other approaches, including phenomenological Schr\"odinger-type equations.
0803.0813
Fernand Renard M
G.J. Gounaris, J. Layssac, F.M. Renard
Genuine SUSY signatures from $ug\to \tilde d \tchi_i^+$ and $ug \to d W^+$, at high energies
19 pages, 10 figures, version to appear in Phys.Rev.D
Phys.Rev.D77:093007,2008
10.1103/PhysRevD.77.093007
PTA/08-009
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the quark-gluon induced process $u g\to \tilde d\tchi_i^+$, including the one loop electroweak (EW) effects in the minimal supersymmetric model (MSSM). This process is determined by four helicity amplitudes, three of which are violating helicity conservation, and another one which respects it and is logarithmically enhanced at high energy. Combining this $u g\to \tilde d\tchi_i^+$ analysis with a corresponding one for $u g \to d W^+$, we obtain simple approximate relations between the two processes, testing the MSSM structure at the amplitude and the cross section levels. These relations become exact at asymptotic energies and, provided the SUSY scale is not too heavy, they may be approximately correct at LHC energies also. In addition to these, we study the 1loop EW corrections to the inclusive $\tilde d\tchi_i^+$ production at LHC, presenting as examples, the $p_T$ and angular distributions. Comparing these to the corresponding predictions for $W$+jet production derived earlier, provides an accurate test of the supersymmetric assignments.
[ { "created": "Thu, 6 Mar 2008 08:13:40 GMT", "version": "v1" }, { "created": "Tue, 1 Apr 2008 08:45:48 GMT", "version": "v2" } ]
2008-11-26
[ [ "Gounaris", "G. J.", "" ], [ "Layssac", "J.", "" ], [ "Renard", "F. M.", "" ] ]
We analyze the quark-gluon induced process $u g\to \tilde d\tchi_i^+$, including the one loop electroweak (EW) effects in the minimal supersymmetric model (MSSM). This process is determined by four helicity amplitudes, three of which are violating helicity conservation, and another one which respects it and is logarithmically enhanced at high energy. Combining this $u g\to \tilde d\tchi_i^+$ analysis with a corresponding one for $u g \to d W^+$, we obtain simple approximate relations between the two processes, testing the MSSM structure at the amplitude and the cross section levels. These relations become exact at asymptotic energies and, provided the SUSY scale is not too heavy, they may be approximately correct at LHC energies also. In addition to these, we study the 1loop EW corrections to the inclusive $\tilde d\tchi_i^+$ production at LHC, presenting as examples, the $p_T$ and angular distributions. Comparing these to the corresponding predictions for $W$+jet production derived earlier, provides an accurate test of the supersymmetric assignments.
1102.3432
Werner Rodejohann
Hans Hettmansperger, Manfred Lindner, Werner Rodejohann
Phenomenological Consequences of sub-leading Terms in See-Saw Formulas
22 pages, matches published version
JHEP 1104:123,2011
10.1007/JHEP04(2011)123
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Several aspects of next-to-leading (NLO) order corrections to see-saw formulas are discussed and phenomenologically relevant situations are identified. We generalize the formalism to calculate the NLO terms developed for the type I see-saw to variants like the inverse, double or linear see-saw, i.e., to cases in which more than two mass scales are present. In the standard type I case with very heavy fermion singlets the sub-leading terms are negligible. However, effects in the percent regime are possible when sub-matrices of the complete neutral fermion mass matrix obey a moderate hierarchy, e.g. weak scale and TeV scale. Examples are cancellations of large terms leading to small neutrino masses, or inverse see-saw scenarios. We furthermore identify situations in which no NLO corrections to certain observables arise, namely for mu-tau symmetry and cases with a vanishing neutrino mass. Finally, we emphasize that the unavoidable unitarity violation in see-saw scenarios with extra fermions can be calculated with the formalism in a straightforward manner.
[ { "created": "Wed, 16 Feb 2011 21:00:04 GMT", "version": "v1" }, { "created": "Tue, 3 May 2011 06:58:56 GMT", "version": "v2" } ]
2011-05-05
[ [ "Hettmansperger", "Hans", "" ], [ "Lindner", "Manfred", "" ], [ "Rodejohann", "Werner", "" ] ]
Several aspects of next-to-leading (NLO) order corrections to see-saw formulas are discussed and phenomenologically relevant situations are identified. We generalize the formalism to calculate the NLO terms developed for the type I see-saw to variants like the inverse, double or linear see-saw, i.e., to cases in which more than two mass scales are present. In the standard type I case with very heavy fermion singlets the sub-leading terms are negligible. However, effects in the percent regime are possible when sub-matrices of the complete neutral fermion mass matrix obey a moderate hierarchy, e.g. weak scale and TeV scale. Examples are cancellations of large terms leading to small neutrino masses, or inverse see-saw scenarios. We furthermore identify situations in which no NLO corrections to certain observables arise, namely for mu-tau symmetry and cases with a vanishing neutrino mass. Finally, we emphasize that the unavoidable unitarity violation in see-saw scenarios with extra fermions can be calculated with the formalism in a straightforward manner.
hep-ph/9807205
null
J.I. Illana (Institut f\"ur Theoretische Physik, Karlsruhe)
Dipole Moments in Supersymmetry
8 pages, 2 figures. LaTeX using appb.sty (included) and epsf.sty. Contribution to the Zeuthen Workshop on Elementary Particle Physics "Loops and Legs in Gauge Theories", Rheinsberg, April 19-24, 1998. Typo in Eq. (5b) corrected. The complete ps-file is also available via WWW at http://www-itp.physik.uni-karlsruhe.de/prep/prep.html
Acta Phys.Polon. B29 (1998) 2753-2761
null
KA-TP-9-1998
hep-ph
null
The one-loop MSSM contributions to the weak dipole moments of the \tau lepton and the b quark (at the Z peak) as well as the electromagnetic and weak dipole form factors of the t quark (at arbitrary s>4m^2_t) are reviewed. Emphasis is given to the relevance of the t-quark CP-violating weak and electric dipole form factors as a part of the full one-loop correction to the process e^+e^- --> t \bar{t} in the MSSM.
[ { "created": "Wed, 1 Jul 1998 08:35:18 GMT", "version": "v1" }, { "created": "Mon, 6 Jul 1998 17:23:40 GMT", "version": "v2" } ]
2007-05-23
[ [ "Illana", "J. I.", "", "Institut für Theoretische Physik, Karlsruhe" ] ]
The one-loop MSSM contributions to the weak dipole moments of the \tau lepton and the b quark (at the Z peak) as well as the electromagnetic and weak dipole form factors of the t quark (at arbitrary s>4m^2_t) are reviewed. Emphasis is given to the relevance of the t-quark CP-violating weak and electric dipole form factors as a part of the full one-loop correction to the process e^+e^- --> t \bar{t} in the MSSM.
2311.13068
Jesus Rendon
Alejandro Ayala, Ricardo L. S. Farias, L. A. Hern\'andez, Ana Julia Mizher, Javier Rend\'on, Cristian Villavicencio and R. Zamora
Magnetic field dependence of the neutral pion longitudinal screening mass in the linear sigma model with quarks
15 pages, 10 figures. arXiv admin note: text overlap with arXiv:2011.03673
Phys. Rev. D 109, 074019 (2024)
10.1103/PhysRevD.109.074019
null
hep-ph hep-lat nucl-th
http://creativecommons.org/publicdomain/zero/1.0/
We use the linear sigma model with quarks to study the magnetic-field-induced modifications on the longitudinal screening mass for the neutral pion at one-loop level. The effects of the magnetic field are introduced into the self-energy, which contains the contributions from all the model particles. We find that, to obtain a reasonable description for the behavior with the field strength, we need to account for the magnetic field dependence of the particle masses. We also find that the couplings need to decrease fast enough with the field strength to then reach constant and smaller values as compared to their vacuum ones. The results illustrate the need to treat the magnetic corrections to the particle masses and couplings in a self-consistent manner, accounting for the backreaction of the field effects for the magnetic field dependence of the rest of the particle species and couplings in the model.
[ { "created": "Wed, 22 Nov 2023 00:01:38 GMT", "version": "v1" }, { "created": "Tue, 23 Apr 2024 03:00:34 GMT", "version": "v2" } ]
2024-04-24
[ [ "Ayala", "Alejandro", "" ], [ "Farias", "Ricardo L. S.", "" ], [ "Hernández", "L. A.", "" ], [ "Mizher", "Ana Julia", "" ], [ "Rendón", "Javier", "" ], [ "Villavicencio", "Cristian", "" ], [ "Zamora", "R.", "" ] ]
We use the linear sigma model with quarks to study the magnetic-field-induced modifications on the longitudinal screening mass for the neutral pion at one-loop level. The effects of the magnetic field are introduced into the self-energy, which contains the contributions from all the model particles. We find that, to obtain a reasonable description for the behavior with the field strength, we need to account for the magnetic field dependence of the particle masses. We also find that the couplings need to decrease fast enough with the field strength to then reach constant and smaller values as compared to their vacuum ones. The results illustrate the need to treat the magnetic corrections to the particle masses and couplings in a self-consistent manner, accounting for the backreaction of the field effects for the magnetic field dependence of the rest of the particle species and couplings in the model.
hep-ph/9810330
Johann Rafelski
Johann Rafelski (Department of Physics, University of Arizona, Tucson, AZ)
Quo Vadis Strangeness? Strangeness - Open Questions
20pages including 5 figures in J.Phys format, Summary talk presented at the International Conference Strangeness in Quark Matter held in Padova, July 1998 v2 comprises more technical details
J.Phys.G25:451-468,1999
10.1088/0954-3899/25/2/035
null
hep-ph
null
The study of strange and also charmed hadronic particle production in nuclear relativistic collisions offers an opportunity to explore the physical properties of the deconfined quark-gluon phase. We survey the recent accomplishments and the future directions of this research program.
[ { "created": "Mon, 12 Oct 1998 17:02:15 GMT", "version": "v1" }, { "created": "Tue, 27 Oct 1998 01:00:23 GMT", "version": "v2" } ]
2008-11-26
[ [ "Rafelski", "Johann", "", "Department of Physics, University of Arizona, Tucson,\n AZ" ] ]
The study of strange and also charmed hadronic particle production in nuclear relativistic collisions offers an opportunity to explore the physical properties of the deconfined quark-gluon phase. We survey the recent accomplishments and the future directions of this research program.
1006.0913
James P. Kneller
James P. Kneller, Cristina Volpe
Turbulence effects on supernova neutrinos
New figure added
Phys.Rev.D82:123004,2010
10.1103/PhysRevD.82.123004
null
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multi-dimensional core-collapse supernova simulations exhibit turbulence of large amplitude and over large scales. As neutrinos pass through the supernova mantle the turbulence is expected to modify their evolution compared to the case where the explosion is free of turbulence. In this paper we study this turbulence effect upon the neutrinos modelling the turbulence expected from multi-dimensional simulations by adding matter density fluctuations to density profiles taken from one-dimensional hydrodynamical simulations. We investigate the impact upon the supernova neutrino transition probabilities as a function of the neutrino mixing angle theta_13 and turbulence amplitude. In the high (H) resonant channel and with large theta_13 values we find that turbulence is effectively two flavor for fluctuation amplitudes <~ 1% and have identified a new effect due to the combination of turbulence and multiple H resonances that leads to a sensitivity to fluctuations amplitudes as small as ~ 0.001%. At small values of theta_13, beyond the range achievable in Earth based experiments, we find that turbulence leads to new flavor transient effects in the channel where the MSW H resonance occurs. Finally, we investigate large amplitude fluctuations which lead to three flavor effects due to broken HL factorization and significant non-resonant transitions and identify two non-resonant turbulence effects, one depending on the theta_13, and the other independent of this angle and due to the low (L) MSW resonance.
[ { "created": "Fri, 4 Jun 2010 14:44:56 GMT", "version": "v1" }, { "created": "Tue, 12 Oct 2010 20:28:39 GMT", "version": "v2" } ]
2010-12-24
[ [ "Kneller", "James P.", "" ], [ "Volpe", "Cristina", "" ] ]
Multi-dimensional core-collapse supernova simulations exhibit turbulence of large amplitude and over large scales. As neutrinos pass through the supernova mantle the turbulence is expected to modify their evolution compared to the case where the explosion is free of turbulence. In this paper we study this turbulence effect upon the neutrinos modelling the turbulence expected from multi-dimensional simulations by adding matter density fluctuations to density profiles taken from one-dimensional hydrodynamical simulations. We investigate the impact upon the supernova neutrino transition probabilities as a function of the neutrino mixing angle theta_13 and turbulence amplitude. In the high (H) resonant channel and with large theta_13 values we find that turbulence is effectively two flavor for fluctuation amplitudes <~ 1% and have identified a new effect due to the combination of turbulence and multiple H resonances that leads to a sensitivity to fluctuations amplitudes as small as ~ 0.001%. At small values of theta_13, beyond the range achievable in Earth based experiments, we find that turbulence leads to new flavor transient effects in the channel where the MSW H resonance occurs. Finally, we investigate large amplitude fluctuations which lead to three flavor effects due to broken HL factorization and significant non-resonant transitions and identify two non-resonant turbulence effects, one depending on the theta_13, and the other independent of this angle and due to the low (L) MSW resonance.
hep-ph/0406281
Glennys R. Farrar
Glennys R. Farrar and Gabrijela Zaharijas
Dark Matter and the Baryon Asymmetry of the Universe
4 pp. Added references and corrected typos
Phys.Rev.Lett. 96 (2006) 041302
null
null
hep-ph astro-ph
null
We present a mechanism to generate the baryon asymmetry of the Universe which preserves the net baryon number created in the Big Bang. If dark matter particles carry baryon number $B_X$, and $\sigma^{\rm annih}_{\bar{X}} < \sigma^{\rm annih}_{X} $, the $\bar{X}$'s freeze out at a higher temperature and have a larger relic density than $X$'s. If $m_X \lsi 4.5 B_X $GeV and the annihilation cross sections differ by $\gsi 10%$, this type of scenario naturally explains the observed $\Omega_{DM} \approx 5 \Omega_b$.
[ { "created": "Thu, 24 Jun 2004 22:13:37 GMT", "version": "v1" }, { "created": "Sun, 27 Jun 2004 16:54:42 GMT", "version": "v2" }, { "created": "Tue, 6 Jul 2004 18:23:22 GMT", "version": "v3" } ]
2007-05-23
[ [ "Farrar", "Glennys R.", "" ], [ "Zaharijas", "Gabrijela", "" ] ]
We present a mechanism to generate the baryon asymmetry of the Universe which preserves the net baryon number created in the Big Bang. If dark matter particles carry baryon number $B_X$, and $\sigma^{\rm annih}_{\bar{X}} < \sigma^{\rm annih}_{X} $, the $\bar{X}$'s freeze out at a higher temperature and have a larger relic density than $X$'s. If $m_X \lsi 4.5 B_X $GeV and the annihilation cross sections differ by $\gsi 10%$, this type of scenario naturally explains the observed $\Omega_{DM} \approx 5 \Omega_b$.
2105.06880
Gong-Ming Yu
Gongming Yu, Yanbing Cai, Yongping Fu, Haitao Yang, Quangui Gao, Qiang Hu, Liyuan Hu, Wei Li, Yushou Song
Coherent photoproduction of low-$p_{T}$ charmonium in peripheral heavy ion collisions within the color dipole model
4 pages, 1 figure
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We calculate the centrality dependence for coherent photoproduction of very low-$p_{T}$ $J/\psi$ at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies within the impact parameter dependent saturated color dipole model. By using the large equivalent photon fluxes, we present the differential cross section of very low-$p_{T}$ $J/\psi$ produced by coherent photonuclear in peripheral heavy-ion collisions. The numerical results demonstrate that our calculation are agree with $J/\psi$ data in peripheral heavy ion collisions at Relativistic Heavy Ion Collider (RHIC) energies.
[ { "created": "Fri, 14 May 2021 15:08:49 GMT", "version": "v1" } ]
2021-05-17
[ [ "Yu", "Gongming", "" ], [ "Cai", "Yanbing", "" ], [ "Fu", "Yongping", "" ], [ "Yang", "Haitao", "" ], [ "Gao", "Quangui", "" ], [ "Hu", "Qiang", "" ], [ "Hu", "Liyuan", "" ], [ "Li", "Wei", "" ], [ "Song", "Yushou", "" ] ]
We calculate the centrality dependence for coherent photoproduction of very low-$p_{T}$ $J/\psi$ at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies within the impact parameter dependent saturated color dipole model. By using the large equivalent photon fluxes, we present the differential cross section of very low-$p_{T}$ $J/\psi$ produced by coherent photonuclear in peripheral heavy-ion collisions. The numerical results demonstrate that our calculation are agree with $J/\psi$ data in peripheral heavy ion collisions at Relativistic Heavy Ion Collider (RHIC) energies.
2009.05195
Javier Monta\~no Dom\'inguez
J. I. Aranda, T. Cisneros-P\'erez, J. Monta\~no, B. Quezadas-Vivian, F. Ram\'irez-Zavaleta, and E. S. Tututi
Revisiting the top quark chromomagnetic dipole moment in the SM
20 pages, 4 figures, this version matches with the published one
null
10.1140/epjp/s13360-021-01102-x
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the anomalous chromomagnetic dipole moment in the Standard Model and show that its triple gluon vertex contribution, with the on-shell gluon ($q^2=0$), generates an infrared divergent pole. Consequently, the chromomagnetic dipole should not be perturbatively evaluated at $q^2=0$. Focusing on this top quark anomaly, denoted as $\hat{\mu}_t(q^2)$, we compute it with the off-shell gluon with a large momentum transfer, just as the $\alpha_s(m_Z^2)$ convention scale, for both spacelike $q^2=-m_Z^2$ and timelike $q^2=m_Z^2$ cases. We found that $\hat{\mu}_t(-m_Z^2)$ $=$ $-0.0224$ $-0.000925i$ and $\hat{\mu}_t(m_Z^2)$ $=$ $-0.0133$ $-0.0267i$. Our $\mathrm{Re}\thinspace\hat{\mu}_t(-m_Z^2)$ matches well with the current experimental value $\hat{\mu}_t^\mathrm{Exp}=-0.024_{-0.009}^{+0.013}(\mathrm{stat})_{-0.011}^{+0.016}(\mathrm{syst})$, and the $\mathrm{Im}\thinspace\hat{\mu}_t(-m_Z^2)$ part is induced by flavour changing charged currents.
[ { "created": "Fri, 11 Sep 2020 01:33:16 GMT", "version": "v1" }, { "created": "Sat, 23 Jan 2021 18:14:49 GMT", "version": "v2" } ]
2021-01-26
[ [ "Aranda", "J. I.", "" ], [ "Cisneros-Pérez", "T.", "" ], [ "Montaño", "J.", "" ], [ "Quezadas-Vivian", "B.", "" ], [ "Ramírez-Zavaleta", "F.", "" ], [ "Tututi", "E. S.", "" ] ]
We revisit the anomalous chromomagnetic dipole moment in the Standard Model and show that its triple gluon vertex contribution, with the on-shell gluon ($q^2=0$), generates an infrared divergent pole. Consequently, the chromomagnetic dipole should not be perturbatively evaluated at $q^2=0$. Focusing on this top quark anomaly, denoted as $\hat{\mu}_t(q^2)$, we compute it with the off-shell gluon with a large momentum transfer, just as the $\alpha_s(m_Z^2)$ convention scale, for both spacelike $q^2=-m_Z^2$ and timelike $q^2=m_Z^2$ cases. We found that $\hat{\mu}_t(-m_Z^2)$ $=$ $-0.0224$ $-0.000925i$ and $\hat{\mu}_t(m_Z^2)$ $=$ $-0.0133$ $-0.0267i$. Our $\mathrm{Re}\thinspace\hat{\mu}_t(-m_Z^2)$ matches well with the current experimental value $\hat{\mu}_t^\mathrm{Exp}=-0.024_{-0.009}^{+0.013}(\mathrm{stat})_{-0.011}^{+0.016}(\mathrm{syst})$, and the $\mathrm{Im}\thinspace\hat{\mu}_t(-m_Z^2)$ part is induced by flavour changing charged currents.
1810.07349
So Chigusa
So Chigusa, Yohei Ema, Takeo Moroi
Probing Electroweakly Interacting Massive Particles with Drell-Yan Process at 100 TeV Hadron Colliders
17 pages, 4 figures, 1 table
null
10.1016/j.physletb.2018.12.011
UT-18-24, KEK-TH-2083, DESY 18-180
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
There are many models beyond the standard model which include electroweakly interacting massive particles (EWIMPs), often in the context of the dark matter. In this paper, we study the indirect search of EWIMPs using a precise measurement of the Drell-Yan cross sections at future $100\,{\rm TeV}$ hadron colliders. It is revealed that this search strategy is suitable in particular for Higgsino and that the Higgsino mass up to about $1.3\,{\rm TeV}$ will be covered at $95\,\%$ C.L. irrespective of the chargino and neutralino mass difference. We also show that the study of the Drell-Yan process provides important and independent information about every kind of EWIMP in addition to Higgsino.
[ { "created": "Wed, 17 Oct 2018 01:43:58 GMT", "version": "v1" }, { "created": "Sat, 16 Feb 2019 09:42:44 GMT", "version": "v2" } ]
2019-02-19
[ [ "Chigusa", "So", "" ], [ "Ema", "Yohei", "" ], [ "Moroi", "Takeo", "" ] ]
There are many models beyond the standard model which include electroweakly interacting massive particles (EWIMPs), often in the context of the dark matter. In this paper, we study the indirect search of EWIMPs using a precise measurement of the Drell-Yan cross sections at future $100\,{\rm TeV}$ hadron colliders. It is revealed that this search strategy is suitable in particular for Higgsino and that the Higgsino mass up to about $1.3\,{\rm TeV}$ will be covered at $95\,\%$ C.L. irrespective of the chargino and neutralino mass difference. We also show that the study of the Drell-Yan process provides important and independent information about every kind of EWIMP in addition to Higgsino.
hep-ph/0102308
Leszek Roszkowski
Takeshi Nihei, Leszek Roszkowski and Roberto Ruiz de Austri
Towards An Accurate Calculation of the Neutralino Relic Density
23 pages, 4 eps figures
JHEP 0105:063,2001
10.1088/1126-6708/2001/05/063
null
hep-ph astro-ph
null
We compute the neutralino relic density in the minimal supersymmetric standard model by using exact expressions for the neutralino annihilation cross section into all tree-level final states, including all contributions and interference terms. We find that several final states may give comparable contributions to the relic density, which illustrates the importance of performing a complete calculation. We compare the exact results with those of the usual expansion method and demonstrate a sizeable discrepancy (of more than 10%) over a significant range of the neutralino mass of up to several tens of GeV which is caused by the presence of resonances and new final-state thresholds. We perform several related checks and comparisons. In particular, we find that the often employed approximate iterative procedure of computing the neutralino freeze-out temperature gives generally very accurate results, except when the expansion method is used near resonances and thresholds.
[ { "created": "Sun, 25 Feb 2001 22:10:58 GMT", "version": "v1" } ]
2010-02-03
[ [ "Nihei", "Takeshi", "" ], [ "Roszkowski", "Leszek", "" ], [ "de Austri", "Roberto Ruiz", "" ] ]
We compute the neutralino relic density in the minimal supersymmetric standard model by using exact expressions for the neutralino annihilation cross section into all tree-level final states, including all contributions and interference terms. We find that several final states may give comparable contributions to the relic density, which illustrates the importance of performing a complete calculation. We compare the exact results with those of the usual expansion method and demonstrate a sizeable discrepancy (of more than 10%) over a significant range of the neutralino mass of up to several tens of GeV which is caused by the presence of resonances and new final-state thresholds. We perform several related checks and comparisons. In particular, we find that the often employed approximate iterative procedure of computing the neutralino freeze-out temperature gives generally very accurate results, except when the expansion method is used near resonances and thresholds.
1210.5059
Gabriel Abelof
Gabriel Abelof (1), Aude Gehrmann-De Ridder (1), Oliver Dekkers (2) ((1) Institute for Theoretical Physics, ETH Z\"urich, (2) Institut f\"ur Theoretische Teilchenphysik und Kosmologie, Aachen University)
Antenna subtraction with massive fermions at NNLO: Double real initial-final configurations
24 pages, 1 figure, 1 Mathematica file attached
null
10.1007/JHEP12(2012)107
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive the integrated forms of specific initial-final tree-level four-parton antenna functions involving a massless initial-state parton and a massive final-state fermion as hard radiators. These antennae are needed in the subtraction terms required to evaluate the double real corrections to $t\bar{t}$ hadronic production at the NNLO level stemming from the partonic processes $q\bar{q}\to t\bar{t}q'\bar{q}'$ and $gg\to t\bar{t}q\bar{q}$.
[ { "created": "Thu, 18 Oct 2012 09:08:18 GMT", "version": "v1" } ]
2015-06-11
[ [ "Abelof", "Gabriel", "" ], [ "Ridder", "Aude Gehrmann-De", "" ], [ "Dekkers", "Oliver", "" ] ]
We derive the integrated forms of specific initial-final tree-level four-parton antenna functions involving a massless initial-state parton and a massive final-state fermion as hard radiators. These antennae are needed in the subtraction terms required to evaluate the double real corrections to $t\bar{t}$ hadronic production at the NNLO level stemming from the partonic processes $q\bar{q}\to t\bar{t}q'\bar{q}'$ and $gg\to t\bar{t}q\bar{q}$.
hep-ph/9908412
Oleg Teryaev
A. Schaefer and O. V. Teryaev
Sum rules for the T-odd fragmentation functions
LATEX, 5 pages; Phys. Rev. D61 (2000) 077903
Phys.Rev. D61 (2000) 077903
10.1103/PhysRevD.61.077903
null
hep-ph
null
The conservation of the intrinsic transverse momentum during parton fragmentation imposes non-trivial constraints on T-odd fragmentation functions. These significantly enhance the differences between the favoured and unfavoured fragmentation functions, which could be relevant to understand the azimuthal asymmetries of charged pion production observed recently by the HERMES collaboration.
[ { "created": "Thu, 19 Aug 1999 13:26:04 GMT", "version": "v1" }, { "created": "Sat, 25 Sep 1999 13:56:47 GMT", "version": "v2" }, { "created": "Mon, 20 Mar 2000 19:40:24 GMT", "version": "v3" } ]
2009-10-31
[ [ "Schaefer", "A.", "" ], [ "Teryaev", "O. V.", "" ] ]
The conservation of the intrinsic transverse momentum during parton fragmentation imposes non-trivial constraints on T-odd fragmentation functions. These significantly enhance the differences between the favoured and unfavoured fragmentation functions, which could be relevant to understand the azimuthal asymmetries of charged pion production observed recently by the HERMES collaboration.
1311.6154
Michal Petran
Michal Petran
Strangeness and charm in quark-gluon hadronization
143 pages
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This dissertation presents a theoretical study of soft hadron production in relativistic heavy-ion collisions. We explore the principles governing the hadronization of the expanding QGP fireball, and to understand its properties. Much of the ongoing effort is to demonstrate the validity of a QGP hadronization model which describes the particle production data accurately. We begin with a centrality study of multistrange hadrons from Au-Au collisions at 62.4 GeV at RHIC. We show that the statistical hadronization model (SHM) well describes particle production in QGP hadronization. For all centralities, the physical properties are compatible with the earlier proposed critical hadronization pressure suggesting universal hadronization conditions of QGP. Heavy-ion collisions at LHC present a new challenge for SHM in describing particle production at TeV energy scales. We show that the chemical non-equilibrium model gives a good description of the hadron production in Pb--Pb collisions at 2.76 TeV consistently as a function of centrality. Moreover, the model parameters assume expected values suggested by previous studies at lower energies. The quark-gluon plasma fireball hadronizes at the same universal hadronization conditions, that is a common critical pressure, entropy and energy density. At LHC energies, a significant amount of charm is expected to be produced and it is therefore crucial to incorporate charm into the present description of particle production. We present an upgraded SHARE with CHARM program, that quantifies the effect of charm on the yield of lighter hadrons and physical properties of the hadronizing fireball. In addition to light flavors ($u,d,s$), SHARE with CHARM describes charm hadron production and decays. We observe, that according to present experimental results, charm decays mainly affect the yields of multistrange particles.
[ { "created": "Sun, 24 Nov 2013 19:03:50 GMT", "version": "v1" } ]
2013-11-26
[ [ "Petran", "Michal", "" ] ]
This dissertation presents a theoretical study of soft hadron production in relativistic heavy-ion collisions. We explore the principles governing the hadronization of the expanding QGP fireball, and to understand its properties. Much of the ongoing effort is to demonstrate the validity of a QGP hadronization model which describes the particle production data accurately. We begin with a centrality study of multistrange hadrons from Au-Au collisions at 62.4 GeV at RHIC. We show that the statistical hadronization model (SHM) well describes particle production in QGP hadronization. For all centralities, the physical properties are compatible with the earlier proposed critical hadronization pressure suggesting universal hadronization conditions of QGP. Heavy-ion collisions at LHC present a new challenge for SHM in describing particle production at TeV energy scales. We show that the chemical non-equilibrium model gives a good description of the hadron production in Pb--Pb collisions at 2.76 TeV consistently as a function of centrality. Moreover, the model parameters assume expected values suggested by previous studies at lower energies. The quark-gluon plasma fireball hadronizes at the same universal hadronization conditions, that is a common critical pressure, entropy and energy density. At LHC energies, a significant amount of charm is expected to be produced and it is therefore crucial to incorporate charm into the present description of particle production. We present an upgraded SHARE with CHARM program, that quantifies the effect of charm on the yield of lighter hadrons and physical properties of the hadronizing fireball. In addition to light flavors ($u,d,s$), SHARE with CHARM describes charm hadron production and decays. We observe, that according to present experimental results, charm decays mainly affect the yields of multistrange particles.
1604.05319
Michael Duerr
Michael Duerr, Pavel Fileviez Perez, Juri Smirnov
New Forces and the 750 GeV Resonance
19 pages, 6 figures
null
null
DESY 16-070
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Recently, the ATLAS and CMS collaborations have pointed out the possible existence of a new resonance with a mass around 750 GeV. We investigate the possibility to identify this new resonance with a spin zero field responsible for the breaking of a new gauge symmetry. We focus on a simple theory where the baryon number is a local symmetry spontaneously broken at the low scale. In this context new vector-like quarks are needed to cancel all baryonic anomalies and define the production mechanism and decays of the new Higgs at the LHC. Assuming the existence of the new Higgs with a mass of 750 GeV at the LHC we find an upper bound on the symmetry breaking scale. Therefore, one expects that a new force associated with baryon number could be discovered at the LHC.
[ { "created": "Mon, 18 Apr 2016 20:00:06 GMT", "version": "v1" } ]
2016-04-21
[ [ "Duerr", "Michael", "" ], [ "Perez", "Pavel Fileviez", "" ], [ "Smirnov", "Juri", "" ] ]
Recently, the ATLAS and CMS collaborations have pointed out the possible existence of a new resonance with a mass around 750 GeV. We investigate the possibility to identify this new resonance with a spin zero field responsible for the breaking of a new gauge symmetry. We focus on a simple theory where the baryon number is a local symmetry spontaneously broken at the low scale. In this context new vector-like quarks are needed to cancel all baryonic anomalies and define the production mechanism and decays of the new Higgs at the LHC. Assuming the existence of the new Higgs with a mass of 750 GeV at the LHC we find an upper bound on the symmetry breaking scale. Therefore, one expects that a new force associated with baryon number could be discovered at the LHC.
1905.05031
Simon King
Luigi Delle Rose, Shaaban Khalil, Simon J.D. King, Stefano Moretti, Ahmed M. Thabt
${}^8$Be Decay Anomaly and Light $Z'$
Prepared for the 2019 EW session of the 54th Rencontres de Moriond, talk presented by Simon King
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this proceedings, we discuss a light (17 MeV) $Z'$ solution to the anomaly observed in the decay of Beryllium-8 by the Atomki collaboration. We detail an anomaly free model with minimal particle content which can satisfy all other experimental constraints with gauge couplings $\mathcal{O}(10^{-4})$.
[ { "created": "Mon, 13 May 2019 13:35:48 GMT", "version": "v1" } ]
2019-05-14
[ [ "Rose", "Luigi Delle", "" ], [ "Khalil", "Shaaban", "" ], [ "King", "Simon J. D.", "" ], [ "Moretti", "Stefano", "" ], [ "Thabt", "Ahmed M.", "" ] ]
In this proceedings, we discuss a light (17 MeV) $Z'$ solution to the anomaly observed in the decay of Beryllium-8 by the Atomki collaboration. We detail an anomaly free model with minimal particle content which can satisfy all other experimental constraints with gauge couplings $\mathcal{O}(10^{-4})$.
1611.01925
Marco Bonvini
Marco Bonvini
Resummations in PDF fits
5 pages. Contribution to the proceedings of DIS 2016
PoS(DIS2016)030
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this contribution I discuss recent and ongoing progress on the inclusion of resummation effects in the fit of parton distributions.
[ { "created": "Mon, 7 Nov 2016 07:51:44 GMT", "version": "v1" } ]
2016-11-08
[ [ "Bonvini", "Marco", "" ] ]
In this contribution I discuss recent and ongoing progress on the inclusion of resummation effects in the fit of parton distributions.
1007.4067
G\'abor Somogyi
G\'abor Somogyi, Paolo Bolzoni and Zolt\'an Tr\'ocs\'anyi
NNLO jet cross sections by subtraction
Talk presented at Loop and Legs in Quantum Field Theory, W\"{o}rlitz, Germany, 25th-30th April 2010
Nucl.Phys.Proc.Suppl.205-206:42-47,2010
10.1016/j.nuclphysbps.2010.08.017
DESY 10-096
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of the NNLO subtraction scheme of [1-4], over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state.
[ { "created": "Fri, 23 Jul 2010 08:33:43 GMT", "version": "v1" } ]
2010-12-13
[ [ "Somogyi", "Gábor", "" ], [ "Bolzoni", "Paolo", "" ], [ "Trócsányi", "Zoltán", "" ] ]
We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of the NNLO subtraction scheme of [1-4], over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state.
1605.03088
Peter A. Sturrock
Peter Sturrock, Gideon Steinitz, Ephraim Fischbach, Alexander Parkhomov, Jeffrey Scargle
Analysis of beta-decay data acquired at the Physikalisch-Technische Bundesanstalt: evidence of a solar influence
13 pages, 19 figures
null
10.1016/j.astropartphys.2016.07.005
null
hep-ph physics.ins-det
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
According to an article entitled Disproof of solar influence on the decay rates of 90Sr/90Y by Kossert and N\"ahle of the Physikalisch-Technische Bundesanstalt (PTB) [1], the PTB measurements show no evidence of variability. We show that, on the contrary, those measurements reveal strong evidence of variability, including an oscillation at 11 year-1 that is suggestive of an influence of internal solar rotation. An analysis of radon beta-decay data acquired at the Geological Survey of Israel (GSI) Laboratory for the same time interval yields strong confirmation of this oscillation.
[ { "created": "Tue, 10 May 2016 16:34:25 GMT", "version": "v1" }, { "created": "Wed, 3 Aug 2016 18:43:26 GMT", "version": "v2" } ]
2016-08-17
[ [ "Sturrock", "Peter", "" ], [ "Steinitz", "Gideon", "" ], [ "Fischbach", "Ephraim", "" ], [ "Parkhomov", "Alexander", "" ], [ "Scargle", "Jeffrey", "" ] ]
According to an article entitled Disproof of solar influence on the decay rates of 90Sr/90Y by Kossert and N\"ahle of the Physikalisch-Technische Bundesanstalt (PTB) [1], the PTB measurements show no evidence of variability. We show that, on the contrary, those measurements reveal strong evidence of variability, including an oscillation at 11 year-1 that is suggestive of an influence of internal solar rotation. An analysis of radon beta-decay data acquired at the Geological Survey of Israel (GSI) Laboratory for the same time interval yields strong confirmation of this oscillation.
1102.4917
Bhag C. Chauhan
Lal Singh, Bhag C. Chauhan, Ravi Dutt, K. K. Sharma and S. Dev
Model Independent Constraints on Solar Neutrinos
21 pages, 3 figures and 13 tables
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using the data from SNO NCD phase, SuperK, Borexino and KamLAND Solar phase, we derive in a model independent way, bounds on the possible components in the solar neutrino flux. We update the limits on the antineutrino ($\bar\nu_x$) flux and sterile ($\nu_s$) component and compare them with the previous results obtained using SNO Salt phase data and data from SuperKamiokande experiments. It is affirmed that the upper bound on $\bar\nu_x$ is independent of the $\nu_s$ component. We recover the $\nu_s$ and $\bar\nu_x$ upper bounds existing in the literature. We also obtain bounds on $f_B$, the SSM normalization factor and the common parameter range for $f_B$ and the $\nu_s$ components in the light of latest data. In summary, we update, in a model independent way, the previous results existing in literature in the light of latest solar neutrino data.
[ { "created": "Thu, 24 Feb 2011 07:24:20 GMT", "version": "v1" } ]
2011-02-25
[ [ "Singh", "Lal", "" ], [ "Chauhan", "Bhag C.", "" ], [ "Dutt", "Ravi", "" ], [ "Sharma", "K. K.", "" ], [ "Dev", "S.", "" ] ]
Using the data from SNO NCD phase, SuperK, Borexino and KamLAND Solar phase, we derive in a model independent way, bounds on the possible components in the solar neutrino flux. We update the limits on the antineutrino ($\bar\nu_x$) flux and sterile ($\nu_s$) component and compare them with the previous results obtained using SNO Salt phase data and data from SuperKamiokande experiments. It is affirmed that the upper bound on $\bar\nu_x$ is independent of the $\nu_s$ component. We recover the $\nu_s$ and $\bar\nu_x$ upper bounds existing in the literature. We also obtain bounds on $f_B$, the SSM normalization factor and the common parameter range for $f_B$ and the $\nu_s$ components in the light of latest data. In summary, we update, in a model independent way, the previous results existing in literature in the light of latest solar neutrino data.
2104.03979
Daniel Wiegand
Radja Boughezal, Frank Petriello, Daniel Wiegand
Disentangling SMEFT operators with future low-energy PVES experiments
22 pages, 7 Figures
Phys. Rev. D 104, 016005 (2021)
10.1103/PhysRevD.104.016005
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the potential of future Parity-Violating Electron Scattering (PVES) data to probe the parameter space of the Standard Model Effective Field Theory (SMEFT). We contrast the constraints derived from Drell-Yan data taken at the Large Hadron Collider (LHC) with projections of the planned PVES experiments SoLID and P2. We show that the PVES data can complement the bounds set by the LHC data in the dimension-6 operator space since it probes different combinations of operators than Drell-Yan. The lower characteristic energy of P2 and SoLID also helps disentangle effects of dimension-6 and dimension-8 operators that are difficult to resolve with LHC Drell-Yan data alone.
[ { "created": "Thu, 8 Apr 2021 18:00:03 GMT", "version": "v1" } ]
2021-07-14
[ [ "Boughezal", "Radja", "" ], [ "Petriello", "Frank", "" ], [ "Wiegand", "Daniel", "" ] ]
We study the potential of future Parity-Violating Electron Scattering (PVES) data to probe the parameter space of the Standard Model Effective Field Theory (SMEFT). We contrast the constraints derived from Drell-Yan data taken at the Large Hadron Collider (LHC) with projections of the planned PVES experiments SoLID and P2. We show that the PVES data can complement the bounds set by the LHC data in the dimension-6 operator space since it probes different combinations of operators than Drell-Yan. The lower characteristic energy of P2 and SoLID also helps disentangle effects of dimension-6 and dimension-8 operators that are difficult to resolve with LHC Drell-Yan data alone.
hep-ph/9210253
null
K. Rajagopal and F. Wilczek
Static and Dynamic Critical Phenomena at a Second Order QCD Phase Transition
phyzzx, 41 pages, 4 figures available as a postscript file from K.R., PUPT-1347, IASSNS-HEP-92/60
Nucl.Phys. B399 (1993) 395-425
10.1016/0550-3213(93)90502-G
null
hep-ph astro-ph hep-lat
null
In QCD with two flavors of massless quarks, the chiral phase transition is plausibly in the same universality class as the classical four component Heisenberg antiferromagnet. Therefore, renormalization group techniques developed in the study of phase transitions can be applied to calculate the critical exponents which characterize the scaling behaviour of universal quantities near the critical point. This approach to the QCD phase transition has implications both for lattice gauge theory and for heavy ion collisions. Future lattice simulations with longer correlation lengths will be able to measure the various exponents and the equation of state for the order parameter as a function of temperature and quark mass which we describe. In a heavy ion collision, the consequence of a long correlation length would be large fluctuations in the number ratio of neutral to charged pions. Unfortunately, we show that this phenomenon will not occur if the plasma stays close to equilibrium as it cools. If the transition is far out of equilibrium and can be modelled as a quench, it is possible that large volumes of the plasma with the pion field correlated will develop, with dramatic phenomenological consequences. }
[ { "created": "Tue, 20 Oct 1992 23:13:41 GMT", "version": "v1" } ]
2009-10-22
[ [ "Rajagopal", "K.", "" ], [ "Wilczek", "F.", "" ] ]
In QCD with two flavors of massless quarks, the chiral phase transition is plausibly in the same universality class as the classical four component Heisenberg antiferromagnet. Therefore, renormalization group techniques developed in the study of phase transitions can be applied to calculate the critical exponents which characterize the scaling behaviour of universal quantities near the critical point. This approach to the QCD phase transition has implications both for lattice gauge theory and for heavy ion collisions. Future lattice simulations with longer correlation lengths will be able to measure the various exponents and the equation of state for the order parameter as a function of temperature and quark mass which we describe. In a heavy ion collision, the consequence of a long correlation length would be large fluctuations in the number ratio of neutral to charged pions. Unfortunately, we show that this phenomenon will not occur if the plasma stays close to equilibrium as it cools. If the transition is far out of equilibrium and can be modelled as a quench, it is possible that large volumes of the plasma with the pion field correlated will develop, with dramatic phenomenological consequences. }
hep-ph/0212407
Harry Lipkin
Harry J. Lipkin (Weizmann Institute, Tel Aviv University, Argonne)
Experimental Challenges for QCD - The past and the future
19 pages, typo in e-mail address corrected
null
10.1142/9789812776310_0010
null
hep-ph
null
The past leaves the surprising experimental successes of the simple constituent quark model to be expained by QCD. Surprising agreement with experiment from simple Sakharov-Zeldovich model (1966) having quarks with effective masses and hyperfine interaction. Nambu's (1966) Colored quarks with gauge gluons gave mass spectrum with only $qqq$ and $\bar q$ bound states. The future opens the way to new insight into QCD from heavy flavor experiments
[ { "created": "Tue, 31 Dec 2002 08:58:15 GMT", "version": "v1" }, { "created": "Thu, 2 Jan 2003 09:49:18 GMT", "version": "v2" } ]
2017-08-23
[ [ "Lipkin", "Harry J.", "", "Weizmann Institute, Tel Aviv University, Argonne" ] ]
The past leaves the surprising experimental successes of the simple constituent quark model to be expained by QCD. Surprising agreement with experiment from simple Sakharov-Zeldovich model (1966) having quarks with effective masses and hyperfine interaction. Nambu's (1966) Colored quarks with gauge gluons gave mass spectrum with only $qqq$ and $\bar q$ bound states. The future opens the way to new insight into QCD from heavy flavor experiments
2004.04780
Anatoly Butkevich
A. V. Butkevich and S. V. Luchuk
Inclusive electron scattering off $^{12}$C, ${}^{40}$Ca, and ${}^{40}$Ar: effects of the meson exchange currents
null
Phys. Rev. C 102, 024602 (2020)
10.1103/PhysRevC.102.024602
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The scattering of electrons on carbon, calcium, and argon targets are analyzed using an approach that incorporates the contributions to the electromagnetic response functions from the quasielastic (QE), inelastic processes, and two-particle and two-hole meson exchange current ($2p-2h$ MEC). This approach describes well the whole energy spectrum of data at very different kinematics. It is shown that the accuracy of the $(e,e')$ cross section calculations in the region between the QE and delta-resonance peaks, where the $2p-2h$ MEC contribution reaches its maximum value, depends on the momentum transfer $|\q|$ and at $|\q|>500$ MeV the calculated and measured cross sections are in agreement within the experimental uncertainties.
[ { "created": "Thu, 9 Apr 2020 19:35:05 GMT", "version": "v1" }, { "created": "Sun, 20 Sep 2020 08:08:11 GMT", "version": "v2" } ]
2020-09-22
[ [ "Butkevich", "A. V.", "" ], [ "Luchuk", "S. V.", "" ] ]
The scattering of electrons on carbon, calcium, and argon targets are analyzed using an approach that incorporates the contributions to the electromagnetic response functions from the quasielastic (QE), inelastic processes, and two-particle and two-hole meson exchange current ($2p-2h$ MEC). This approach describes well the whole energy spectrum of data at very different kinematics. It is shown that the accuracy of the $(e,e')$ cross section calculations in the region between the QE and delta-resonance peaks, where the $2p-2h$ MEC contribution reaches its maximum value, depends on the momentum transfer $|\q|$ and at $|\q|>500$ MeV the calculated and measured cross sections are in agreement within the experimental uncertainties.
hep-ph/9901360
Silvano Simula
G. Ricco, S. Simula and M. Battaglieri
Power corrections in the longitudinal and transverse structure functions of proton and deuteron
revised version with only minor changes, to appear in Nuclear Physics B
Nucl.Phys. B555 (1999) 306-334
10.1016/S0550-3213(99)00302-8
preprint INFN-RM3 98/2
hep-ph
null
Power corrections to the Q**2 behaviour of the low-order moments of both the longitudinal and transverse structure functions of proton and deuteron have been investigated using available phenomenological fits of existing data in the Q**2 range between 1 and 20 (GeV/c)**2. The Natchmann definition of the moments has been adopted for disentangling properly target-mass and dynamical higher-twist effects in the data. The leading twist has been treated at next-to-leading order in the strong coupling constant and the effects of higher orders of the perturbative series have been estimated using a renormalon-inspired model. The contributions of (target-dependent) multiparton correlations to both 1/Q**2 and 1/Q**4 power terms have been determined in the transverse channel, while the longitudinal one appears to be consistent with a pure infrared renormalon picture in the whole Q**2-range between 1 and 20 (GeV/c)**2. Finally, the extracted twist-2 contribution in the deuteron turns out to be compatible with the hypothesis of an enhanced d-quark parton distribution at large x.
[ { "created": "Wed, 20 Jan 1999 17:56:06 GMT", "version": "v1" }, { "created": "Tue, 25 May 1999 10:36:33 GMT", "version": "v2" } ]
2009-10-31
[ [ "Ricco", "G.", "" ], [ "Simula", "S.", "" ], [ "Battaglieri", "M.", "" ] ]
Power corrections to the Q**2 behaviour of the low-order moments of both the longitudinal and transverse structure functions of proton and deuteron have been investigated using available phenomenological fits of existing data in the Q**2 range between 1 and 20 (GeV/c)**2. The Natchmann definition of the moments has been adopted for disentangling properly target-mass and dynamical higher-twist effects in the data. The leading twist has been treated at next-to-leading order in the strong coupling constant and the effects of higher orders of the perturbative series have been estimated using a renormalon-inspired model. The contributions of (target-dependent) multiparton correlations to both 1/Q**2 and 1/Q**4 power terms have been determined in the transverse channel, while the longitudinal one appears to be consistent with a pure infrared renormalon picture in the whole Q**2-range between 1 and 20 (GeV/c)**2. Finally, the extracted twist-2 contribution in the deuteron turns out to be compatible with the hypothesis of an enhanced d-quark parton distribution at large x.
hep-ph/0006290
A. Bialas
A.Bialas, M.Kucharczyk, H.Palka and K.Zalewski
Mass dependence of HBT correlations in e^+e^- annihilation
15 pages, 3 figures
Phys.Rev.D62:114007,2000
10.1103/PhysRevD.62.114007
TPJU-6/2000
hep-ph
null
Mass dependence of the effective source radii, observed in hadronic $Z^0$ decays by several LEP I experiments, is analyzed in a model which assumes proportionality between four-momentum of a produced particle and the four-vector describing its space-time position at the freeze-out. It is shown that this relation (commonly accepted in description of high-energy collisions) can explain the data, provided all particles are emitted from a "tube" of $\sim 1$ fm in diameter at a constant proper time $\sim 1.5$ fm.
[ { "created": "Mon, 26 Jun 2000 11:07:39 GMT", "version": "v1" } ]
2014-11-17
[ [ "Bialas", "A.", "" ], [ "Kucharczyk", "M.", "" ], [ "Palka", "H.", "" ], [ "Zalewski", "K.", "" ] ]
Mass dependence of the effective source radii, observed in hadronic $Z^0$ decays by several LEP I experiments, is analyzed in a model which assumes proportionality between four-momentum of a produced particle and the four-vector describing its space-time position at the freeze-out. It is shown that this relation (commonly accepted in description of high-energy collisions) can explain the data, provided all particles are emitted from a "tube" of $\sim 1$ fm in diameter at a constant proper time $\sim 1.5$ fm.
2207.10090
Joshua Foster
Christopher Dessert, Joshua W. Foster, Yujin Park, Benjamin R. Safdi, Weishuang Linda Xu
Higgsino Dark Matter Confronts 14 years of Fermi Gamma Ray Data
7+20 pages, 3+23 figures
null
10.1103/PhysRevLett.130.201001
MIT-CTP/5454
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Thermal higgsino dark matter (DM), with mass around 1 TeV, is a well-motivated, minimal DM scenario that arises in supersymmetric extensions of the Standard Model. Higgsinos may naturally be the lightest superpartners in Split-supersymmetry models that decouple the scalar superpartners while keeping higgsinos and gauginos close to the TeV scale. Higgsino DM may annihilate today to give continuum gamma-ray emission at energies less than a TeV in addition to a line-like signature at energies equal to the mass. Previous searches for higgsino DM, for example with the H.E.S.S. gamma-ray telescope, have not reached the necessary sensitivity to probe the higgsino annihilation cross-section. In this work we make use of 14 years of $\textit{Fermi}$ gamma-ray data at energies above $\sim$10 GeV to search for the continuum emission near the Galactic Center from higgsino annihilation. We interpret our results using DM profiles from Milky Way analogue galaxies in the FIRE-2 hydrodynamic cosmological simulations. We set the strongest constraints to-date on higgsino-like DM. Our results show a mild, $\sim$2$\sigma$ preference for higgsino DM with a mass near the thermal higgsino mass and, depending on the DM density profile, the expected cross-section.
[ { "created": "Wed, 20 Jul 2022 18:00:00 GMT", "version": "v1" } ]
2023-05-31
[ [ "Dessert", "Christopher", "" ], [ "Foster", "Joshua W.", "" ], [ "Park", "Yujin", "" ], [ "Safdi", "Benjamin R.", "" ], [ "Xu", "Weishuang Linda", "" ] ]
Thermal higgsino dark matter (DM), with mass around 1 TeV, is a well-motivated, minimal DM scenario that arises in supersymmetric extensions of the Standard Model. Higgsinos may naturally be the lightest superpartners in Split-supersymmetry models that decouple the scalar superpartners while keeping higgsinos and gauginos close to the TeV scale. Higgsino DM may annihilate today to give continuum gamma-ray emission at energies less than a TeV in addition to a line-like signature at energies equal to the mass. Previous searches for higgsino DM, for example with the H.E.S.S. gamma-ray telescope, have not reached the necessary sensitivity to probe the higgsino annihilation cross-section. In this work we make use of 14 years of $\textit{Fermi}$ gamma-ray data at energies above $\sim$10 GeV to search for the continuum emission near the Galactic Center from higgsino annihilation. We interpret our results using DM profiles from Milky Way analogue galaxies in the FIRE-2 hydrodynamic cosmological simulations. We set the strongest constraints to-date on higgsino-like DM. Our results show a mild, $\sim$2$\sigma$ preference for higgsino DM with a mass near the thermal higgsino mass and, depending on the DM density profile, the expected cross-section.
1901.08281
Li Lin Yang
Michal Czakon, Andrea Ferroglia, Alexander Mitov, Davide Pagani, Andrew S. Papanastasiou, Benjamin D. Pecjak, Darren J. Scott, Ioannis Tsinikos, Xing Wang, Li Lin Yang, Marco Zaro
Top-quark pair production at complete-NLO accuracy with NNLO+NNLL$'$ corrections in QCD
Contribution to the proceedings of the 11th International Workshop on Top Quark Physics (TOP2018); v3: significantly modified version with more numeric results
Chin.Phys.C 44 (2020) 8, 083104
10.1088/1674-1137/44/8/083104
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe predictions for top-quark pair differential distributions at hadron colliders, which combine state-of-the-art NNLO QCD calculations and NLO electroweak corrections together with double resummation at NNLL$'$ accuracy of threshold logarithms and small-mass logarithms. This is the first time that such a combination has appeared in the literature. Numerical results are presented for the invariant-mass distribution, the transverse-momentum distribution as well as rapidity distributions.
[ { "created": "Thu, 24 Jan 2019 08:33:35 GMT", "version": "v1" }, { "created": "Fri, 25 Jan 2019 08:20:25 GMT", "version": "v2" }, { "created": "Tue, 25 Feb 2020 06:22:28 GMT", "version": "v3" } ]
2020-08-06
[ [ "Czakon", "Michal", "" ], [ "Ferroglia", "Andrea", "" ], [ "Mitov", "Alexander", "" ], [ "Pagani", "Davide", "" ], [ "Papanastasiou", "Andrew S.", "" ], [ "Pecjak", "Benjamin D.", "" ], [ "Scott", "Darren J.", "" ], [ "Tsinikos", "Ioannis", "" ], [ "Wang", "Xing", "" ], [ "Yang", "Li Lin", "" ], [ "Zaro", "Marco", "" ] ]
We describe predictions for top-quark pair differential distributions at hadron colliders, which combine state-of-the-art NNLO QCD calculations and NLO electroweak corrections together with double resummation at NNLL$'$ accuracy of threshold logarithms and small-mass logarithms. This is the first time that such a combination has appeared in the literature. Numerical results are presented for the invariant-mass distribution, the transverse-momentum distribution as well as rapidity distributions.
hep-ph/0406005
Ramazan Sever
Sameer M. Ikhdair and Ramazan Sever
Mass Spectra of Heavy Quarkonia and B_{c} Decay Constant for Static Scalar-Vector Interactions with Relativistic Kinematics
35 pages
Int.J.Mod.Phys.A20:6509-6531,2005
10.1142/S0217751X05021294
null
hep-ph
null
We reproduce masses of the self-conjugate and non-self-conjugate mesons in the context of the spinless Salpeter equation taking into account the relativistic kinematics and the quark spins. The hyperfine splittings for the ${\rm 2S}$ charmonium and ${\rm 1S}$ bottomonium are also calculated. Further, the pseudoscalar and vector decay constants of the $B_{c}$ meson and the unperturbed radial wave function at the origin are also calculated. We have obtained a local equation with a complete relativistic corrections to a class of three attractive static interaction potentials of the general form $V(r)=-Ar^{-\beta}+\kappa r^{\beta}+V_{0},$ with $\beta =1,1/2,~3/4$ decomposed into scalar and vector parts in the form $V_{V}(r)=-Ar^{-\beta }+(1-\epsilon)\kappa r^{\beta}$ and $V_{S}(r)=\epsilon \kappa r^{\beta }+V_{0};$ where $0\leq \epsilon \leq 1.$ We have used the shifted large-N-expansion technique (SLNET) to solve the reduced equation for the scalar $(\epsilon =1),$ equal mixture of scalar-vector $(\epsilon =1/2),$ and vector $(\epsilon =0)$ confinement interaction kernels. The energy eigenvalues are carried out up to the third order approximation.
[ { "created": "Mon, 31 May 2004 23:47:29 GMT", "version": "v1" } ]
2010-11-05
[ [ "Ikhdair", "Sameer M.", "" ], [ "Sever", "Ramazan", "" ] ]
We reproduce masses of the self-conjugate and non-self-conjugate mesons in the context of the spinless Salpeter equation taking into account the relativistic kinematics and the quark spins. The hyperfine splittings for the ${\rm 2S}$ charmonium and ${\rm 1S}$ bottomonium are also calculated. Further, the pseudoscalar and vector decay constants of the $B_{c}$ meson and the unperturbed radial wave function at the origin are also calculated. We have obtained a local equation with a complete relativistic corrections to a class of three attractive static interaction potentials of the general form $V(r)=-Ar^{-\beta}+\kappa r^{\beta}+V_{0},$ with $\beta =1,1/2,~3/4$ decomposed into scalar and vector parts in the form $V_{V}(r)=-Ar^{-\beta }+(1-\epsilon)\kappa r^{\beta}$ and $V_{S}(r)=\epsilon \kappa r^{\beta }+V_{0};$ where $0\leq \epsilon \leq 1.$ We have used the shifted large-N-expansion technique (SLNET) to solve the reduced equation for the scalar $(\epsilon =1),$ equal mixture of scalar-vector $(\epsilon =1/2),$ and vector $(\epsilon =0)$ confinement interaction kernels. The energy eigenvalues are carried out up to the third order approximation.
2312.01908
Wen-Xuan Zhang
Zhen-Hui Zhu, Wen-Xuan Zhang and Duojie Jia
Triply heavy tetraquark states: masses and other properties
19 pages, 6 figures, 5 tables and two appendices, created by RevTex 4
Eur. Phys. J. C (2024) 84:344
10.1140/epjc/s10052-024-12700-1
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
In this work, we study masses and other static properties of triply heavy tetraquarks in the unified framework of the MIT bag which incorporates chromomagnetic interactions and enhanced binding energy. The masses, magnetic moments and charge radii of all strange and nonstrange (ground) states of triply heavy tetraquarks are computed, suggesting that all of triply heavy tetraquarks are above the respective two-meson thresholds. We also estimate relative decay widths of main decay channels of two-heavy mesons for these tetraquarks.
[ { "created": "Mon, 4 Dec 2023 14:13:09 GMT", "version": "v1" }, { "created": "Thu, 4 Apr 2024 02:11:15 GMT", "version": "v2" } ]
2024-06-14
[ [ "Zhu", "Zhen-Hui", "" ], [ "Zhang", "Wen-Xuan", "" ], [ "Jia", "Duojie", "" ] ]
In this work, we study masses and other static properties of triply heavy tetraquarks in the unified framework of the MIT bag which incorporates chromomagnetic interactions and enhanced binding energy. The masses, magnetic moments and charge radii of all strange and nonstrange (ground) states of triply heavy tetraquarks are computed, suggesting that all of triply heavy tetraquarks are above the respective two-meson thresholds. We also estimate relative decay widths of main decay channels of two-heavy mesons for these tetraquarks.
0909.3199
Vojtech Kundrat
Milos V. Lokajicek, V. Kundrat
Elastic pp scattering and the internal structure of colliding proton
7 pages, 4 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Elastic scattering data gained for proton-proton collisions at high energies are being analyzed at the present practically only with the help of purely phenomenological mathematical models. And the question exists whether in the impact parameter plane the elastic processes may be interpreted as central or peripheral. From realistic point of view the peripherality should be preferred and one may expect that nucleon dimensions should manifest in some way in elastic data. It will be demonstrated that the elastic pp data at the energy of 53 GeV in the interval |t| from (0., 4.) [GeV^2] may be interpreted well as the superposition of mutual collisions of two internal structures with maximal external dimensions; the approximate dimensions and frequencies of corresponding structures being established on the basis of measured elastic data.
[ { "created": "Thu, 17 Sep 2009 12:22:24 GMT", "version": "v1" } ]
2009-09-18
[ [ "Lokajicek", "Milos V.", "" ], [ "Kundrat", "V.", "" ] ]
Elastic scattering data gained for proton-proton collisions at high energies are being analyzed at the present practically only with the help of purely phenomenological mathematical models. And the question exists whether in the impact parameter plane the elastic processes may be interpreted as central or peripheral. From realistic point of view the peripherality should be preferred and one may expect that nucleon dimensions should manifest in some way in elastic data. It will be demonstrated that the elastic pp data at the energy of 53 GeV in the interval |t| from (0., 4.) [GeV^2] may be interpreted well as the superposition of mutual collisions of two internal structures with maximal external dimensions; the approximate dimensions and frequencies of corresponding structures being established on the basis of measured elastic data.
hep-ph/9912444
Arnd Leike
Stephen Godfrey, Pat Kalyniak, Basim Kamal and Arnd Leike
Constraints on Couplings of Extra Gauge Bosons from e+e- --> nu nubar gamma
8 pages Latex, 8 figures included with epsf, contribution to the Linear Collider workshop
null
null
null
hep-ph
null
If extra gauge bosons are observed at the LHC or at a linear e+e- collider, the reaction e+e- --> nu nubar gamma can give information on the couplings (W' nu l) and (Z' nu nubar). The total cross section and polarization asymmetries are the most sensitive observables for such a measurement. Small systematic errors are crucial to obtain reasonable coupling constraints, especially for a high luminosity collider.
[ { "created": "Tue, 21 Dec 1999 14:25:38 GMT", "version": "v1" } ]
2007-05-23
[ [ "Godfrey", "Stephen", "" ], [ "Kalyniak", "Pat", "" ], [ "Kamal", "Basim", "" ], [ "Leike", "Arnd", "" ] ]
If extra gauge bosons are observed at the LHC or at a linear e+e- collider, the reaction e+e- --> nu nubar gamma can give information on the couplings (W' nu l) and (Z' nu nubar). The total cross section and polarization asymmetries are the most sensitive observables for such a measurement. Small systematic errors are crucial to obtain reasonable coupling constraints, especially for a high luminosity collider.
hep-ph/0302213
A. A. Arkhipov
A.A. Arkhipov
Kaluza-Klein Picture and Mass Spectrum of Two-Pion System
LaTex2e, 11 pages; 4 references added, 2 empty cells filled
null
null
null
hep-ph hep-ex nucl-ex
null
In this note we present additional arguments in favour of Kaluza and Klein picture of the world. In fact, we have shown that formula (\ref{KKpi}) provided by Kaluza-Klein approach with the fundamental scale early calculated (Eq.\ref{scale} \cite{1}) gives an excellent description for the mass spectrum of two-pion system.
[ { "created": "Mon, 24 Feb 2003 18:12:40 GMT", "version": "v1" }, { "created": "Tue, 25 Feb 2003 16:19:40 GMT", "version": "v2" }, { "created": "Wed, 2 Apr 2003 18:13:26 GMT", "version": "v3" } ]
2007-05-23
[ [ "Arkhipov", "A. A.", "" ] ]
In this note we present additional arguments in favour of Kaluza and Klein picture of the world. In fact, we have shown that formula (\ref{KKpi}) provided by Kaluza-Klein approach with the fundamental scale early calculated (Eq.\ref{scale} \cite{1}) gives an excellent description for the mass spectrum of two-pion system.
2302.04892
Victor Martin Lozano
Danyer Perez Adan, Henning Bahl, Alexander Grohsjean, Victor Martin Lozano, Christian Schwanenberger, Georg Weiglein
A new LHC search for dark matter produced via heavy Higgs bosons using simplified models
27 pages, 8 figures, 4 tables
JHEP 08 (2023) 151
10.1007/JHEP08(2023)151
DESY 23-014, EFI-22-10
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Searches for dark matter produced via scalar resonances in final states consisting of Standard Model (SM) particles and missing transverse momentum are of high relevance at the LHC. Motivated by dark-matter portal models, most existing searches are optimized for unbalanced decay topologies for which the missing momentum recoils against the visible SM particles. In this work, we show that existing searches are also sensitive to a wider class of models, which we characterize by a recently presented simplified model framework. We point out that searches for models with a balanced decay topology can be further improved with more dedicated analysis strategies. For this study, we investigate the feasibility of a new search for bottom-quark associated neutral Higgs production with a $b \bar b Z + p_\text{T}^\text{miss}$ final state and perform a detailed collider analysis. Our projected results in the different simplified model topologies investigated here can be easily reinterpreted in a wide range of models of physics beyond the SM, which we explicitly demonstrate for the example of the Two-Higgs-Doublet model with an additional pseudoscalar Higgs boson.
[ { "created": "Thu, 9 Feb 2023 19:00:10 GMT", "version": "v1" } ]
2023-09-19
[ [ "Adan", "Danyer Perez", "" ], [ "Bahl", "Henning", "" ], [ "Grohsjean", "Alexander", "" ], [ "Lozano", "Victor Martin", "" ], [ "Schwanenberger", "Christian", "" ], [ "Weiglein", "Georg", "" ] ]
Searches for dark matter produced via scalar resonances in final states consisting of Standard Model (SM) particles and missing transverse momentum are of high relevance at the LHC. Motivated by dark-matter portal models, most existing searches are optimized for unbalanced decay topologies for which the missing momentum recoils against the visible SM particles. In this work, we show that existing searches are also sensitive to a wider class of models, which we characterize by a recently presented simplified model framework. We point out that searches for models with a balanced decay topology can be further improved with more dedicated analysis strategies. For this study, we investigate the feasibility of a new search for bottom-quark associated neutral Higgs production with a $b \bar b Z + p_\text{T}^\text{miss}$ final state and perform a detailed collider analysis. Our projected results in the different simplified model topologies investigated here can be easily reinterpreted in a wide range of models of physics beyond the SM, which we explicitly demonstrate for the example of the Two-Higgs-Doublet model with an additional pseudoscalar Higgs boson.
1306.6808
Rafal Maciula
Rafal Maciula and Antoni Szczurek
Charmed mesons and leptons from semileptonic decays at the LHC
5 pages, 4 figures, talk given by R. Maciula at the XXI. International Workshop on Deep-Inelastic Scattering and Related Subjects DIS 2013, 22-26 April 2013, Marseille, France
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss production of charmed mesons as well as electrons/muons from semileptonic decays of charm and bottom mesons in proton-proton collisions at the LHC. The cross section for inclusive production of $c \bar c$ and $b \bar b$ pairs is calculated in the framework of the $k_{\perp}$-factorization approach. Here, the KMR and Jung CCFM unintegrated gluon distribution functions are used. Theoretical uncertainties of the model related to the choice of renormalization and factorization scales as well as due to the quark mass are also discussed. The hadronization of charm and bottom quarks is included within the fragmentation functions technique. Inclusive differential distributions in transverse momentum of charmed mesons are presented and compared to recent results of the ALICE collaboration. Furthermore, we also consider production of different $D \bar D$ pairs in unique kinematics of forward rapidities of the LHCb experiment. Kinematical correlations in azimuthal angle $\varphi_{D\bar D}$ and invariant mass $M_{D \bar D}$ distributions are presented and compared to LHCb data. Furthermore, the semileptonic decays of charm and bottom mesons are done with the help of decay functions found by fitting recent semileptonic data obtained by the CLEO and BABAR collaborations. Inclusive differential distributions in transverse momentum of leptons for several kinematical regions are presented and compared to recent results of the ALICE and CMS collaborations.
[ { "created": "Fri, 28 Jun 2013 12:18:05 GMT", "version": "v1" } ]
2013-07-01
[ [ "Maciula", "Rafal", "" ], [ "Szczurek", "Antoni", "" ] ]
We discuss production of charmed mesons as well as electrons/muons from semileptonic decays of charm and bottom mesons in proton-proton collisions at the LHC. The cross section for inclusive production of $c \bar c$ and $b \bar b$ pairs is calculated in the framework of the $k_{\perp}$-factorization approach. Here, the KMR and Jung CCFM unintegrated gluon distribution functions are used. Theoretical uncertainties of the model related to the choice of renormalization and factorization scales as well as due to the quark mass are also discussed. The hadronization of charm and bottom quarks is included within the fragmentation functions technique. Inclusive differential distributions in transverse momentum of charmed mesons are presented and compared to recent results of the ALICE collaboration. Furthermore, we also consider production of different $D \bar D$ pairs in unique kinematics of forward rapidities of the LHCb experiment. Kinematical correlations in azimuthal angle $\varphi_{D\bar D}$ and invariant mass $M_{D \bar D}$ distributions are presented and compared to LHCb data. Furthermore, the semileptonic decays of charm and bottom mesons are done with the help of decay functions found by fitting recent semileptonic data obtained by the CLEO and BABAR collaborations. Inclusive differential distributions in transverse momentum of leptons for several kinematical regions are presented and compared to recent results of the ALICE and CMS collaborations.
hep-ph/0209301
Wilfried Buchmuller
W. Buchm\"uller, P. Di Bari, M. Pl\"umacher
A bound on neutrino masses from baryogenesis
8 pages, 2 figures
Phys.Lett. B547 (2002) 128-132
10.1016/S0370-2693(02)02758-2
DESY 02-107, OUTP-02-36-P
hep-ph astro-ph hep-ex hep-th
null
Properties of neutrinos, the lightest of all elementary particles, may be the origin of the entire matter-antimatter asymmetry of the universe. This requires that neutrinos are Majorana particles, which are equal to their antiparticles, and that their masses are sufficiently small. Leptogenesis, the theory explaining the cosmic matter-antimatter asymmetry, predicts that all neutrino masses are smaller than 0.2 eV, which will be tested by forthcoming laboratory experiments and by cosmology.
[ { "created": "Wed, 25 Sep 2002 15:54:59 GMT", "version": "v1" } ]
2009-11-07
[ [ "Buchmüller", "W.", "" ], [ "Di Bari", "P.", "" ], [ "Plümacher", "M.", "" ] ]
Properties of neutrinos, the lightest of all elementary particles, may be the origin of the entire matter-antimatter asymmetry of the universe. This requires that neutrinos are Majorana particles, which are equal to their antiparticles, and that their masses are sufficiently small. Leptogenesis, the theory explaining the cosmic matter-antimatter asymmetry, predicts that all neutrino masses are smaller than 0.2 eV, which will be tested by forthcoming laboratory experiments and by cosmology.
2104.12190
Mohammad Athar SAJJAD
M. Sajjad Athar, and S. K. Singh
The low energy inclusive $\nu_{\mu} (\nu_{e})-^{12}$C scattering revisited
12 pages, 3 figures, 3 tables
null
null
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
We have reviewed the current status of the inclusive neutrino scattering from $^{12}$C in the low energy region corresponding to the neutrino beams from the pion, muon and kaon decaying at rest. The theoretical calculations of total cross sections in various nuclear models with special emphasis on the recent experiments with the monoenergetic neutrinos from KDAR [1] along with the older experiments from KARMEN and LSND collaborations have been discussed in the context of the recent works by Akbar et al. [2] and Nikolakopoulos et al. [3]. The inadequacy of the various theoretical models used to explain the experimental results on the inclusive neutrino scattering from nuclei at low energies has been highlighted and the need for a better understanding of the nuclear medium effects beyond the impulse approximation has been emphasized.
[ { "created": "Sun, 25 Apr 2021 16:05:21 GMT", "version": "v1" } ]
2021-04-27
[ [ "Athar", "M. Sajjad", "" ], [ "Singh", "S. K.", "" ] ]
We have reviewed the current status of the inclusive neutrino scattering from $^{12}$C in the low energy region corresponding to the neutrino beams from the pion, muon and kaon decaying at rest. The theoretical calculations of total cross sections in various nuclear models with special emphasis on the recent experiments with the monoenergetic neutrinos from KDAR [1] along with the older experiments from KARMEN and LSND collaborations have been discussed in the context of the recent works by Akbar et al. [2] and Nikolakopoulos et al. [3]. The inadequacy of the various theoretical models used to explain the experimental results on the inclusive neutrino scattering from nuclei at low energies has been highlighted and the need for a better understanding of the nuclear medium effects beyond the impulse approximation has been emphasized.
1101.3557
G\'abor Somogyi
Gabor Somogyi
Angular integrals in d dimensions
30 pages, discussion slightly extended by mentioning the existence of contiguous relations for H-functions, new references added
null
10.1063/1.3615515
DESY 11-004, SFB/CPP-11-02, LPN11-03
hep-ph math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the evaluation of certain d dimensional angular integrals which arise in perturbative field theory calculations. We find that the angular integral with n denominators can be computed in terms of a certain special function, the so-called H-function of several variables. We also present several illustrative examples of the general result and briefly consider some applications.
[ { "created": "Tue, 18 Jan 2011 21:03:05 GMT", "version": "v1" }, { "created": "Thu, 10 Mar 2011 13:20:20 GMT", "version": "v2" } ]
2015-05-27
[ [ "Somogyi", "Gabor", "" ] ]
We discuss the evaluation of certain d dimensional angular integrals which arise in perturbative field theory calculations. We find that the angular integral with n denominators can be computed in terms of a certain special function, the so-called H-function of several variables. We also present several illustrative examples of the general result and briefly consider some applications.
1111.0353
Shunzo Kumano
M. Hirai, H. Kawamura, S. Kumano, K. Saito
Selected topics on parton distribution functions
8 pages, LaTeX, to be published in AIP proceedings, 8th Circum-Pan-Pacific Symposium on High Energy Spin Physics, June 20-24, 2011, Cairns, Australia
null
10.1063/1.3667318
KEK-TH-1494; J-PARC-TH-0002
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report recent studies on structure functions of the nucleon and nuclei. First, clustering effects are investigated in the structure function F_2 of Be-9 for explaining an unusual nuclear correction found in a JLab experiment. We propose that high densities created by formation of clustering structure like 2*alpha+neutron in Be-9 is the origin of the unexpected JLab result by using the antisymmetrized molecular dynamics (AMD). There is an approved proposal at JLab to investigate the structure functions of light nuclei including the cluster structure, so that much details will become clear in a few years. Second, tensor-polarized quark and antiquark distributions are obtained by analyzing HERMES measurements on the structure function b_1 for the deuteron. The result suggests a finite tensor polarization for antiquark distributions, which is an interesting topic for further theoretical and experimental investigations. An experimental proposal exists at JLab for measuring b_1 of the deuteron as a new tensor-structure study in 2010's. Furthermore, the antiquark tensor polarization could be measured by polarized deuteron Drell-Yan processes at hadron facilities such as J-PARC and GSI-FAIR. Third, the recent CDF dijet anomaly is investigated within the standard model by considering possible modifications of the strange-quark distribution. We find that the shape of a dijet-mass spectrum changes depending on the strange-quark distribution. It indicates that the CDF excess could be partially explained as a PDF effect, particularly by the strangeness in the nucleon, within the standard model if the excess at m_{jj}~140 GeV is not a sharp peak.
[ { "created": "Wed, 2 Nov 2011 00:16:30 GMT", "version": "v1" } ]
2015-06-03
[ [ "Hirai", "M.", "" ], [ "Kawamura", "H.", "" ], [ "Kumano", "S.", "" ], [ "Saito", "K.", "" ] ]
We report recent studies on structure functions of the nucleon and nuclei. First, clustering effects are investigated in the structure function F_2 of Be-9 for explaining an unusual nuclear correction found in a JLab experiment. We propose that high densities created by formation of clustering structure like 2*alpha+neutron in Be-9 is the origin of the unexpected JLab result by using the antisymmetrized molecular dynamics (AMD). There is an approved proposal at JLab to investigate the structure functions of light nuclei including the cluster structure, so that much details will become clear in a few years. Second, tensor-polarized quark and antiquark distributions are obtained by analyzing HERMES measurements on the structure function b_1 for the deuteron. The result suggests a finite tensor polarization for antiquark distributions, which is an interesting topic for further theoretical and experimental investigations. An experimental proposal exists at JLab for measuring b_1 of the deuteron as a new tensor-structure study in 2010's. Furthermore, the antiquark tensor polarization could be measured by polarized deuteron Drell-Yan processes at hadron facilities such as J-PARC and GSI-FAIR. Third, the recent CDF dijet anomaly is investigated within the standard model by considering possible modifications of the strange-quark distribution. We find that the shape of a dijet-mass spectrum changes depending on the strange-quark distribution. It indicates that the CDF excess could be partially explained as a PDF effect, particularly by the strangeness in the nucleon, within the standard model if the excess at m_{jj}~140 GeV is not a sharp peak.
hep-ph/0211401
Jungdae Kim
C. S. Kim and J. D. Kim
A Flexible Parametrization of CKM matrix via Singular-Value-Decomposition Method
20 pages, 2 figures
Eur.Phys.J.C28:55-61,2003
10.1140/epjc/s2003-01151-3
null
hep-ph
null
We investigate a flexible method in which we can test the unitarity of the quark flavor mixing matrix step-by-step. Singular-Value-Decomposition (SVD) techniques are used in analyzing the mixing matrix over a broader parameter region than the unitarity region. Unitary constraints make us extract CP violating properties without any specific parametrization when the magnitudes of at least three mixing matrix elements in three generation quark mixing are given. This method can also be applied to the analysis of lepton flavor mixing, in which only a few moduli are presently measured.
[ { "created": "Tue, 26 Nov 2002 10:34:50 GMT", "version": "v1" } ]
2010-11-23
[ [ "Kim", "C. S.", "" ], [ "Kim", "J. D.", "" ] ]
We investigate a flexible method in which we can test the unitarity of the quark flavor mixing matrix step-by-step. Singular-Value-Decomposition (SVD) techniques are used in analyzing the mixing matrix over a broader parameter region than the unitarity region. Unitary constraints make us extract CP violating properties without any specific parametrization when the magnitudes of at least three mixing matrix elements in three generation quark mixing are given. This method can also be applied to the analysis of lepton flavor mixing, in which only a few moduli are presently measured.
hep-ph/9804355
Christopher Kolda
K.S. Babu, Christopher Kolda, John March-Russell and Frank Wilczek
CP Violation, Higgs Couplings, and Supersymmetry
13 pages LaTeX, 4 figures (some typos fixed, discussion clarified)
Phys. Rev. D 59, 016004 (1998)
10.1103/PhysRevD.59.016004
IASSNS-HEP-98/30
hep-ph
null
Supersymmetric extensions of the standard model generically contain additional sources of CP violation. We discuss how at one loop a potentially large CP violating coupling of the lightest Higgs, h^0, to leptons is induced in the minimal supersymmetric standard model (MSSM). The CP violating couplings of h^0 in extensions of the MSSM, such as the next-to-minimal supersymmetric standard model (NMSSM) are also considered. We indicate how this CP violation might be observed; in particular a polarization-dependent production asymmetry, in the context of a muon collider, provides a means to access this coupling cleanly. In the MSSM, existing limits on the electric dipole moment (EDM) of the electron, coupled with standard universality assumptions, severly constrains any such signal. Nevertheless, extensions of the MSSM, such as the NMSSM, allow CP-violating signals as large as 100%.
[ { "created": "Tue, 21 Apr 1998 21:21:06 GMT", "version": "v1" }, { "created": "Thu, 29 Oct 1998 22:09:42 GMT", "version": "v2" } ]
2016-08-25
[ [ "Babu", "K. S.", "" ], [ "Kolda", "Christopher", "" ], [ "March-Russell", "John", "" ], [ "Wilczek", "Frank", "" ] ]
Supersymmetric extensions of the standard model generically contain additional sources of CP violation. We discuss how at one loop a potentially large CP violating coupling of the lightest Higgs, h^0, to leptons is induced in the minimal supersymmetric standard model (MSSM). The CP violating couplings of h^0 in extensions of the MSSM, such as the next-to-minimal supersymmetric standard model (NMSSM) are also considered. We indicate how this CP violation might be observed; in particular a polarization-dependent production asymmetry, in the context of a muon collider, provides a means to access this coupling cleanly. In the MSSM, existing limits on the electric dipole moment (EDM) of the electron, coupled with standard universality assumptions, severly constrains any such signal. Nevertheless, extensions of the MSSM, such as the NMSSM, allow CP-violating signals as large as 100%.
1704.00546
Antoni Szczurek
Izabela Babiarz, Rafal Staszewski and Antoni Szczurek
Multi-parton interactions and rapidity gap survival probability in jet-gap-jet processes
18 pages, 10 figures
null
10.1016/j.physletb.2017.05.095
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss an application of dynamical multi-parton interaction model, tuned to measurements of underlying event topology, for a description of destroying rapidity gaps in the jet-gap-jet processes at the LHC. We concentrate on the dynamical origin of the mechanism of destroying the rapidity gap. The cross section for jet-gap-jet is calculated within LL BFKL approximation. We discuss the topology of final states without and with the MPI effects. We discuss some examples of selected kinematical situations (fixed jet rapidities and transverse momenta) as distributions averaged over the dynamics of the jet-gap-jet scattering. The color-singlet ladder exchange amplitude for the partonic subprocess is implemented into the \textsc{Pythia 8} generator, which is then used for hadronisation and for the simulation of the MPI effects. Several differential distributions are shown and discussed. We present the ratio of cross section calculated with and without MPI effects as a function of rapidity gap in between the jets.
[ { "created": "Mon, 3 Apr 2017 12:24:44 GMT", "version": "v1" } ]
2017-06-14
[ [ "Babiarz", "Izabela", "" ], [ "Staszewski", "Rafal", "" ], [ "Szczurek", "Antoni", "" ] ]
We discuss an application of dynamical multi-parton interaction model, tuned to measurements of underlying event topology, for a description of destroying rapidity gaps in the jet-gap-jet processes at the LHC. We concentrate on the dynamical origin of the mechanism of destroying the rapidity gap. The cross section for jet-gap-jet is calculated within LL BFKL approximation. We discuss the topology of final states without and with the MPI effects. We discuss some examples of selected kinematical situations (fixed jet rapidities and transverse momenta) as distributions averaged over the dynamics of the jet-gap-jet scattering. The color-singlet ladder exchange amplitude for the partonic subprocess is implemented into the \textsc{Pythia 8} generator, which is then used for hadronisation and for the simulation of the MPI effects. Several differential distributions are shown and discussed. We present the ratio of cross section calculated with and without MPI effects as a function of rapidity gap in between the jets.
hep-ph/0110134
Georgii N. Shestakov
N.N. Achasov and G.N. Shestakov (Institute for Mathematics, Novosibirsk, Russia)
Effective Lagrangians Induced by the Anomalous Wess-Zumino Action and $I^G(J^{PC})=1^-(1^{-+})$ Exotic States
Parallel session talk given at HADRON 2001, Protvino, Russia, August 28, 2001. LaTex, 5 pages, 1 figure
AIP Conf.Proc. 619 (2002) 599-602
10.1063/1.1482499
null
hep-ph hep-ex nucl-th
null
A simple dynamical model for the exotic waves with $I^G(J^{PC})=1^-(1^{-+})$ in the reactions $\rho\pi\to\rho\pi$, $\rho\pi\to\eta\pi$, $\rho\pi\to\eta'\pi$, $ \rho\pi\to(K^*\bar K+\bar K^*K)$, and in the related ones, is constructed beyond the scope of the quark-gluon approach. The model satisfies unitarity and analyticity and uses as a "priming" the anomalous non-diagonal $VPPP$ interaction which couples together the four channels $\rho\pi$, $\eta\pi$, $ \eta'\pi$, and $K^*\bar K+\bar K^*K$. The possibility of the resonance-like behavior of the $I^G(J^{PC})=1^-(1^{-+})$ amplitudes belonging to the $\{10\}- \{\bar{10}\}$ and $\{8\}$ representations of SU(3) as well as their mixing is demonstrated explicitly in the 1.3--1.6 GeV mass range which, according to the current experiments, is really rich in exotics.
[ { "created": "Wed, 10 Oct 2001 10:18:13 GMT", "version": "v1" } ]
2009-11-07
[ [ "Achasov", "N. N.", "", "Institute for Mathematics,\n Novosibirsk, Russia" ], [ "Shestakov", "G. N.", "", "Institute for Mathematics,\n Novosibirsk, Russia" ] ]
A simple dynamical model for the exotic waves with $I^G(J^{PC})=1^-(1^{-+})$ in the reactions $\rho\pi\to\rho\pi$, $\rho\pi\to\eta\pi$, $\rho\pi\to\eta'\pi$, $ \rho\pi\to(K^*\bar K+\bar K^*K)$, and in the related ones, is constructed beyond the scope of the quark-gluon approach. The model satisfies unitarity and analyticity and uses as a "priming" the anomalous non-diagonal $VPPP$ interaction which couples together the four channels $\rho\pi$, $\eta\pi$, $ \eta'\pi$, and $K^*\bar K+\bar K^*K$. The possibility of the resonance-like behavior of the $I^G(J^{PC})=1^-(1^{-+})$ amplitudes belonging to the $\{10\}- \{\bar{10}\}$ and $\{8\}$ representations of SU(3) as well as their mixing is demonstrated explicitly in the 1.3--1.6 GeV mass range which, according to the current experiments, is really rich in exotics.
hep-ph/9606417
J. Gunion
V. Barger (Wisconsin), M.S. Berger (Indiana), J.F. Gunion (U.C. Davis), T. Han (U.C. Davis)
Studying a Strongly Interacting Electroweak Sector via Longitudinal Gauge Boson Scattering at a Muon Collider
34 pages, uuencoded tex file and postscript figure files submitted, full postscript file, including embedded figures, is available via anonymous ftp at ftp://ucdhep.ucdavis.edu/gunion/strongw_mupmum.ps
Phys.Rev.D55:142-154,1997
10.1103/PhysRevD.55.142
UCD-96-19
hep-ph hep-ex
null
We discuss the excellent prospects for a detailed study of a strongly interacting electroweak sector at a muon collider with c.m. energy $\rts\sim 4\tev$. For expected luminosity of $L=200-1000\fbi$ per year, $\mup\mum$ and $\mup\mup$ (or $\mum\mum$) collisions can be used to study longitudinal $\wp\wm$ and $\wp\wp$ (or $\wm\wm$) scattering with considerable precision. In particular, detailed measurements of the distribution in the $VV$ pair masses ($V=\wpm,Z$) will be possible. The shape and magnitude of these distributions will provide a powerful tool for determining the nature of strong gauge boson interactions. Event rates will be large enough that projection techniques can be used to directly isolate final states with different polarizations of the $V$'s and verify that the strong interaction cross section excess is mainly in the longitudinal-longitudinal mode.
[ { "created": "Mon, 24 Jun 1996 02:21:10 GMT", "version": "v1" } ]
2009-09-15
[ [ "Barger", "V.", "", "Wisconsin" ], [ "Berger", "M. S.", "", "Indiana" ], [ "Gunion", "J. F.", "", "U.C.\n Davis" ], [ "Han", "T.", "", "U.C. Davis" ] ]
We discuss the excellent prospects for a detailed study of a strongly interacting electroweak sector at a muon collider with c.m. energy $\rts\sim 4\tev$. For expected luminosity of $L=200-1000\fbi$ per year, $\mup\mum$ and $\mup\mup$ (or $\mum\mum$) collisions can be used to study longitudinal $\wp\wm$ and $\wp\wp$ (or $\wm\wm$) scattering with considerable precision. In particular, detailed measurements of the distribution in the $VV$ pair masses ($V=\wpm,Z$) will be possible. The shape and magnitude of these distributions will provide a powerful tool for determining the nature of strong gauge boson interactions. Event rates will be large enough that projection techniques can be used to directly isolate final states with different polarizations of the $V$'s and verify that the strong interaction cross section excess is mainly in the longitudinal-longitudinal mode.
1305.1645
Benjamin Fuks
Benjamin Fuks, Michael Klasen, David R. Lamprea, Marcel Rothering
QCD resummation in the framework of supersymmetry
4 pages, 2 figures, contribution to the proceedings of Moriond QCD 2013
null
null
CERN-PH-TH/2013-096, IPHC-PHENO-13-04, MS-TP-13-11
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by current searches for electroweak superpartners at the Large Hadron Collider, we present precision predictions for pair production of such particles in the framework of the Minimal Supersymmetric Standard Model. We make use of various QCD resummation formalisms and match the results to pure perturbative QCD computations. We study the impact of scale variations and compare our results to predictions obtained by means of traditionally used Monte Carlo event generators.
[ { "created": "Tue, 7 May 2013 21:05:36 GMT", "version": "v1" } ]
2013-05-09
[ [ "Fuks", "Benjamin", "" ], [ "Klasen", "Michael", "" ], [ "Lamprea", "David R.", "" ], [ "Rothering", "Marcel", "" ] ]
Motivated by current searches for electroweak superpartners at the Large Hadron Collider, we present precision predictions for pair production of such particles in the framework of the Minimal Supersymmetric Standard Model. We make use of various QCD resummation formalisms and match the results to pure perturbative QCD computations. We study the impact of scale variations and compare our results to predictions obtained by means of traditionally used Monte Carlo event generators.
2407.16386
Francesco Grippa
Francesco Grippa, Gaetano Lambiase and Tanmay Kumar Poddar
Constraints on scalar and vector dark matter admixed neutron stars with linear and quadratic couplings
33 pages, 12 figures, 2 tables, comments are welcome
null
null
null
hep-ph astro-ph.CO gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the effect of dark matter scalar and vector-mediated interactions on dark matter admixed neutron stars. In particular, we exploit the two-fluid formalism of Tolman-Oppenheimer-Volkoff equations as generic framework for dark matter admixed neutron stars. The fluids couple to each other only by gravity. In particular, the baryonic sector is described by the BSk22 equation of state, whereas we employ a relativistic mean field model for the dark matter, where we include the interaction of dark massive fermions with light dark scalar and vector mediators. We consider both the linear and the quadratic scalar interactions with the dark fermion. In the quadratic scalar scenario, we take into account a quartic self-interaction that significantly affects the stellar properties. Interestingly, in both cases, the effect of the scalar coupling is smaller than that of the vector, though quantitative differences arise. We also compute the sound speed of DM, finding that the scalar and quadratic couplings have an important influence on it. We compare our results with GW1708017, GW190425 and NICER data and constrain DM couplings and mass.
[ { "created": "Tue, 23 Jul 2024 11:19:57 GMT", "version": "v1" } ]
2024-07-24
[ [ "Grippa", "Francesco", "" ], [ "Lambiase", "Gaetano", "" ], [ "Poddar", "Tanmay Kumar", "" ] ]
We study the effect of dark matter scalar and vector-mediated interactions on dark matter admixed neutron stars. In particular, we exploit the two-fluid formalism of Tolman-Oppenheimer-Volkoff equations as generic framework for dark matter admixed neutron stars. The fluids couple to each other only by gravity. In particular, the baryonic sector is described by the BSk22 equation of state, whereas we employ a relativistic mean field model for the dark matter, where we include the interaction of dark massive fermions with light dark scalar and vector mediators. We consider both the linear and the quadratic scalar interactions with the dark fermion. In the quadratic scalar scenario, we take into account a quartic self-interaction that significantly affects the stellar properties. Interestingly, in both cases, the effect of the scalar coupling is smaller than that of the vector, though quantitative differences arise. We also compute the sound speed of DM, finding that the scalar and quadratic couplings have an important influence on it. We compare our results with GW1708017, GW190425 and NICER data and constrain DM couplings and mass.
2212.10089
Marcela Pel\'aez
Marcela Pel\'aez, Urko Reinosa, Julien Serreau and Nicol\'as Wschebor
Small parameters in infrared QCD: The pion decay constant
21 pages, 11 figures
null
10.1103/PhysRevD.107.054025
null
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
We continue our investigation of the QCD dynamics in terms of the Curci-Ferrari effective Lagrangian, a deformation of the Faddeev-Popov one in the Landau gauge with a tree-level gluon mass term. In a previous work we have studied the dynamics of chiral symmetry breaking at the level of the quark propagator and, in particular, the dynamical generation of a constituent quark mass. In the present article, we study the associated Goldstone mode, the pion, and we compute the pion decay constant in the chiral limit. Our approach exploits the fact that the coupling (defined in the Taylor scheme) in the pure gauge sector is perturbative, as observed in lattice simulations which, together with a $1/N_c$-expansion, allows for a systematic, controllable approximation scheme in the low energy regime of QCD. At leading order, this leads to the well-known rainbow-ladder resummation. We study the region of parameter space of the model that gives physical values of the pion decay constant. This allows one to constrain the gluon mass parameter as a function of the coupling using a physically measured quantity.
[ { "created": "Tue, 20 Dec 2022 09:04:52 GMT", "version": "v1" } ]
2023-03-29
[ [ "Peláez", "Marcela", "" ], [ "Reinosa", "Urko", "" ], [ "Serreau", "Julien", "" ], [ "Wschebor", "Nicolás", "" ] ]
We continue our investigation of the QCD dynamics in terms of the Curci-Ferrari effective Lagrangian, a deformation of the Faddeev-Popov one in the Landau gauge with a tree-level gluon mass term. In a previous work we have studied the dynamics of chiral symmetry breaking at the level of the quark propagator and, in particular, the dynamical generation of a constituent quark mass. In the present article, we study the associated Goldstone mode, the pion, and we compute the pion decay constant in the chiral limit. Our approach exploits the fact that the coupling (defined in the Taylor scheme) in the pure gauge sector is perturbative, as observed in lattice simulations which, together with a $1/N_c$-expansion, allows for a systematic, controllable approximation scheme in the low energy regime of QCD. At leading order, this leads to the well-known rainbow-ladder resummation. We study the region of parameter space of the model that gives physical values of the pion decay constant. This allows one to constrain the gluon mass parameter as a function of the coupling using a physically measured quantity.
hep-ph/0607147
Yukihiro Mimura
Bhaskar Dutta and Yukihiro Mimura
B(s)-B(s)bar Mixing in Supersymmetric Grand Unified Models
5 pages, 3 figures. Modifications in the text and the title, references added, results unchanged, to appear in PRL
Phys.Rev.Lett.97:241802,2006
10.1103/PhysRevLett.97.241802
MIFP-06-18
hep-ph
null
We study B_s-\bar{B}_s mixing in grand unified SO(10), SU(5) models where the mixings among the second and third generation squarks arise due to the existence of flavor violating sources in the Dirac and Majorana couplings which are responsible for neutrino mixings. We find that when the branching ratio of tau->mu gamma decay is enhanced to be around the current experimental bound, B_s-\bar{B}_s mixing may also contain large contribution from supersymmetry in the SO(10) boundary condition. Consequently, the phase of B_s-\bar{B}_s mixing is large (especially for small tan beta and large scalar mass m_0) and can be tested by measuring CP asymmetries of B_s decay modes.
[ { "created": "Wed, 12 Jul 2006 20:45:44 GMT", "version": "v1" }, { "created": "Fri, 24 Nov 2006 21:08:04 GMT", "version": "v2" } ]
2008-11-26
[ [ "Dutta", "Bhaskar", "" ], [ "Mimura", "Yukihiro", "" ] ]
We study B_s-\bar{B}_s mixing in grand unified SO(10), SU(5) models where the mixings among the second and third generation squarks arise due to the existence of flavor violating sources in the Dirac and Majorana couplings which are responsible for neutrino mixings. We find that when the branching ratio of tau->mu gamma decay is enhanced to be around the current experimental bound, B_s-\bar{B}_s mixing may also contain large contribution from supersymmetry in the SO(10) boundary condition. Consequently, the phase of B_s-\bar{B}_s mixing is large (especially for small tan beta and large scalar mass m_0) and can be tested by measuring CP asymmetries of B_s decay modes.
2303.01548
Gonzalo Villa
Francesco Muia, Fernando Quevedo, Andreas Schachner, Gonzalo Villa
Testing BSM Physics with Gravitational Waves
16 pages + appendix, 7 figures v2: minor edits, references added. Matches published version
JCAP 09 (2023) 006
10.1088/1475-7516/2023/09/006
null
hep-ph astro-ph.CO gr-qc
http://creativecommons.org/licenses/by/4.0/
The Cosmic Gravitational Wave Background (CGWB) is an irreducible background of gravitational waves generated by particle exchange in the early Universe plasma. Standard Model particles contribute to such a stochastic background with a peak at $f\sim 80$ GHz. Any physics beyond the Standard Model (BSM) may modify the CGWB spectrum, making it a potential testing ground for BSM physics. We consider the impact of general BSM scenarios on the CGWB, including an arbitrary number of hidden sectors. We find that the largest amplitude of the CGWB comes from the sector that dominates the energy density after reheating and confirm the dominance of the SM for standard cosmological histories. For non-standard cosmological histories, such as those with a stiff equation of state $\omega >1/3$, like in kination, BSM physics may dominate and modify the spectrum substantially. We conclude that, if the CGWB is detected at lower frequencies and amplitudes compared to that of the SM, it will hint at extra massive degrees of freedom or hidden sectors. If it is instead measured at higher values, it will imply a period with $\omega >1/3$. We argue that for scenarios with periods of kination in the early Universe, a significant fraction of the parameter space can be ruled out from dark radiation bounds at BBN.
[ { "created": "Thu, 2 Mar 2023 19:29:09 GMT", "version": "v1" }, { "created": "Mon, 11 Sep 2023 17:20:47 GMT", "version": "v2" } ]
2023-09-12
[ [ "Muia", "Francesco", "" ], [ "Quevedo", "Fernando", "" ], [ "Schachner", "Andreas", "" ], [ "Villa", "Gonzalo", "" ] ]
The Cosmic Gravitational Wave Background (CGWB) is an irreducible background of gravitational waves generated by particle exchange in the early Universe plasma. Standard Model particles contribute to such a stochastic background with a peak at $f\sim 80$ GHz. Any physics beyond the Standard Model (BSM) may modify the CGWB spectrum, making it a potential testing ground for BSM physics. We consider the impact of general BSM scenarios on the CGWB, including an arbitrary number of hidden sectors. We find that the largest amplitude of the CGWB comes from the sector that dominates the energy density after reheating and confirm the dominance of the SM for standard cosmological histories. For non-standard cosmological histories, such as those with a stiff equation of state $\omega >1/3$, like in kination, BSM physics may dominate and modify the spectrum substantially. We conclude that, if the CGWB is detected at lower frequencies and amplitudes compared to that of the SM, it will hint at extra massive degrees of freedom or hidden sectors. If it is instead measured at higher values, it will imply a period with $\omega >1/3$. We argue that for scenarios with periods of kination in the early Universe, a significant fraction of the parameter space can be ruled out from dark radiation bounds at BBN.
0812.2489
Manuel Toharia
Aleksandr Azatov, Manuel Toharia and Lijun Zhu
Radion Mediated Flavor Changing Neutral Currents
4 pages, 2 figures, 1 table
Phys.Rev.D80:031701,2009
10.1103/PhysRevD.80.031701
UMD-PP-08-22
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the context of a warped extra-dimension with Standard Model fields in the bulk, we obtain the general flavor structure of the Radion couplings to fermions and show that the result is independent on the particular nature of the Higgs mechanism (bulk or brane localized). These couplings will be generically misaligned with respect to the fermion mass matrix when the fermion bulk mass parameters are not all degenerate. When the Radion is light enough, the generic size of these tree-level flavor changing couplings will be strongly constrained by the experimental bounds on $\Delta F=2$ processes. At the LHC the possibility of a heavier Radion decaying into top and charm quarks is then considered as a promising signal to probe the flavor structure of both the Radion sector and the whole scenario.
[ { "created": "Fri, 12 Dec 2008 21:48:58 GMT", "version": "v1" } ]
2010-04-30
[ [ "Azatov", "Aleksandr", "" ], [ "Toharia", "Manuel", "" ], [ "Zhu", "Lijun", "" ] ]
In the context of a warped extra-dimension with Standard Model fields in the bulk, we obtain the general flavor structure of the Radion couplings to fermions and show that the result is independent on the particular nature of the Higgs mechanism (bulk or brane localized). These couplings will be generically misaligned with respect to the fermion mass matrix when the fermion bulk mass parameters are not all degenerate. When the Radion is light enough, the generic size of these tree-level flavor changing couplings will be strongly constrained by the experimental bounds on $\Delta F=2$ processes. At the LHC the possibility of a heavier Radion decaying into top and charm quarks is then considered as a promising signal to probe the flavor structure of both the Radion sector and the whole scenario.
0901.1750
Sarah Andreas
Sarah Andreas, Michel H.G. Tytgat and Quentin Swillens
Neutrinos from Inert Doublet Dark Matter
25 pages, 13 figures; v2: minor changes, more detailed discussion on capture, conclusions unchanged, matches published version (JCAP)
JCAP 0904:004,2009
10.1088/1475-7516/2009/04/004
ULB-TH/09-02
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the signatures of neutrinos produced in the annihilation of WIMP dark matter in the Earth, the Sun and at the Galactic centre within the framework of the Inert Doublet Model and extensions. We consider a dark matter candidate, that we take to be one of the neutral components of an extra Higgs doublet, in three distinct mass ranges, which have all been shown previously to be consistent with both WMAP abundance and direct detection experiments exclusion limits. Specifically, we consider a light WIMP with mass between 4 and 8 GeV (low), a WIMP with mass around 60-70 GeV (middle) and a heavy WIMP with mass above 500 GeV (high). In the first case, we show that capture in the Sun may be constrained using Super-Kamiokande data. In the last two cases, we argue that indirect detection through neutrinos is challenging but not altogether excluded. For middle masses, we try to make the most benefit of the proximity of the so-called 'iron resonance' that might enhance the capture of the dark matter candidate by the Earth. The signal from the Earth is further enhanced if light right-handed Majorana neutrinos are introduced, in which case the scalar dark matter candidate may annihilate into pairs of mono-energetic neutrinos. In the case of high masses, detection of neutrinos from the Galactic centre might be possible, provided the dark matter abundance is substantially boosted.
[ { "created": "Tue, 13 Jan 2009 18:05:32 GMT", "version": "v1" }, { "created": "Thu, 16 Apr 2009 13:06:18 GMT", "version": "v2" } ]
2010-01-05
[ [ "Andreas", "Sarah", "" ], [ "Tytgat", "Michel H. G.", "" ], [ "Swillens", "Quentin", "" ] ]
We investigate the signatures of neutrinos produced in the annihilation of WIMP dark matter in the Earth, the Sun and at the Galactic centre within the framework of the Inert Doublet Model and extensions. We consider a dark matter candidate, that we take to be one of the neutral components of an extra Higgs doublet, in three distinct mass ranges, which have all been shown previously to be consistent with both WMAP abundance and direct detection experiments exclusion limits. Specifically, we consider a light WIMP with mass between 4 and 8 GeV (low), a WIMP with mass around 60-70 GeV (middle) and a heavy WIMP with mass above 500 GeV (high). In the first case, we show that capture in the Sun may be constrained using Super-Kamiokande data. In the last two cases, we argue that indirect detection through neutrinos is challenging but not altogether excluded. For middle masses, we try to make the most benefit of the proximity of the so-called 'iron resonance' that might enhance the capture of the dark matter candidate by the Earth. The signal from the Earth is further enhanced if light right-handed Majorana neutrinos are introduced, in which case the scalar dark matter candidate may annihilate into pairs of mono-energetic neutrinos. In the case of high masses, detection of neutrinos from the Galactic centre might be possible, provided the dark matter abundance is substantially boosted.
1911.00552
Jacob Barandes
Jacob A. Barandes
On Magnetic Forces and Work
9 pages, no figures
Foundations of Physics, 51(4):79, July 2021
10.1007/s10701-021-00483-4
null
hep-ph hep-th physics.class-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We address a long-standing debate over whether classical magnetic forces can do work, ultimately answering the question in the affirmative. In detail, we couple a classical particle with intrinsic spin and elementary dipole moments to the electromagnetic field, derive the appropriate generalization of the Lorentz force law, show that the particle's dipole moments must be collinear with its spin axis, and argue that the magnetic field does mechanical work on the particle's elementary magnetic dipole moment. As consistency checks, we calculate the overall system's energy-momentum and angular momentum, and show that their local conservation equations lead to the same force law and therefore the same conclusions about magnetic forces and work. We also compute the system's Belinfante-Rosenfeld energy-momentum tensor.
[ { "created": "Fri, 1 Nov 2019 18:48:56 GMT", "version": "v1" }, { "created": "Wed, 26 Jul 2023 23:29:12 GMT", "version": "v2" } ]
2023-07-28
[ [ "Barandes", "Jacob A.", "" ] ]
We address a long-standing debate over whether classical magnetic forces can do work, ultimately answering the question in the affirmative. In detail, we couple a classical particle with intrinsic spin and elementary dipole moments to the electromagnetic field, derive the appropriate generalization of the Lorentz force law, show that the particle's dipole moments must be collinear with its spin axis, and argue that the magnetic field does mechanical work on the particle's elementary magnetic dipole moment. As consistency checks, we calculate the overall system's energy-momentum and angular momentum, and show that their local conservation equations lead to the same force law and therefore the same conclusions about magnetic forces and work. We also compute the system's Belinfante-Rosenfeld energy-momentum tensor.
hep-ph/9912354
Leonard Lesniak
R. Kaminski, L. Lesniak and K. Rybicki
Further study of the pi-pi S-wave isoscalar amplitude below the K - Kbar threshold
15 pages, 4 figures (added Fig.2)
ActaPhys.Polon.B31:895-908,2000
null
INP 1837/PH, Dec. 1999
hep-ph
null
We continue the analysis of S-wave production amplitudes for the reaction pi- p -> pi+ pi- n involving the data obtained by the CERN--Cracow-Munich collaboration on a transversely polarized target at 17.2 GeV/c pi- momentum. This study deals with the region below the K - Kbar threshold. In particular, we study the "up-steep" solution containing a narrow S-wave resonance under the rho(770). This solution exhibits a considerable inelasticity (eta) which does not have any physical interpretation. Assuming that this inelasticity behaviour represents an unlikely fluctuation we impose eta = 1 for all data points. This leads to non-physical results in one third of the pi+pi- effective mass bins and in the remaining mass bins some parameters behave in a queer way. The situation is even worse for the "down-steep" solution. We conclude that the 17.2 GeV data cannot be described by a relatively narrow f0(750). The "down-flat" and "up-steep" solutions which easily pass the eta = 1 constraint exhibit a slow increase of phase shifts in the rho(770) mass range.
[ { "created": "Wed, 15 Dec 1999 13:44:02 GMT", "version": "v1" }, { "created": "Fri, 17 Dec 1999 13:04:04 GMT", "version": "v2" } ]
2008-11-26
[ [ "Kaminski", "R.", "" ], [ "Lesniak", "L.", "" ], [ "Rybicki", "K.", "" ] ]
We continue the analysis of S-wave production amplitudes for the reaction pi- p -> pi+ pi- n involving the data obtained by the CERN--Cracow-Munich collaboration on a transversely polarized target at 17.2 GeV/c pi- momentum. This study deals with the region below the K - Kbar threshold. In particular, we study the "up-steep" solution containing a narrow S-wave resonance under the rho(770). This solution exhibits a considerable inelasticity (eta) which does not have any physical interpretation. Assuming that this inelasticity behaviour represents an unlikely fluctuation we impose eta = 1 for all data points. This leads to non-physical results in one third of the pi+pi- effective mass bins and in the remaining mass bins some parameters behave in a queer way. The situation is even worse for the "down-steep" solution. We conclude that the 17.2 GeV data cannot be described by a relatively narrow f0(750). The "down-flat" and "up-steep" solutions which easily pass the eta = 1 constraint exhibit a slow increase of phase shifts in the rho(770) mass range.
1105.2842
Andrea Ferroglia
A. Sirlin
Radiative Correction to the anti-nu_e (nu_e) Spectrum in beta-Decay
Sentences added at the end of the conclusions, additional reference included, two typographical errors in the text corrected. 8 pages
Phys.Rev.D84:014021,2011
10.1103/PhysRevD.84.014021
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive an analytic expression for the O(alpha) radiative correction to the anti-nu_e (nu_e) spectrum in allowed beta-decay. The m -> 0 limit is convergent and leads to a very simple result (m is the electron mass). This is in sharp contrast to the correction to the e^- (e^+) spectrum, that diverges as m -> 0, an important difference that we explain on theoretical grounds. After discussing some of their general properties, we use the corrections to the anti-nu_e and e^- spectra to derive the corresponding correction to the e^- -> anti-nu_e conversion, a relation that is of considerable interest for reactor studies of neutrino oscillations.
[ { "created": "Fri, 13 May 2011 21:33:09 GMT", "version": "v1" }, { "created": "Mon, 12 Sep 2011 19:42:53 GMT", "version": "v2" } ]
2011-09-13
[ [ "Sirlin", "A.", "" ] ]
We derive an analytic expression for the O(alpha) radiative correction to the anti-nu_e (nu_e) spectrum in allowed beta-decay. The m -> 0 limit is convergent and leads to a very simple result (m is the electron mass). This is in sharp contrast to the correction to the e^- (e^+) spectrum, that diverges as m -> 0, an important difference that we explain on theoretical grounds. After discussing some of their general properties, we use the corrections to the anti-nu_e and e^- spectra to derive the corresponding correction to the e^- -> anti-nu_e conversion, a relation that is of considerable interest for reactor studies of neutrino oscillations.
1812.01096
Fernando Serna A
Fernando E. Serna, Chen Chen, and Bruno El-Bennich
Interplay of dynamical and explicit chiral symmetry breaking effects on a quark
null
Phys. Rev. D 99, 094027 (2019)
10.1103/PhysRevD.99.094027
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
The relative contributions of explicit and dynamical chiral symmetry breaking in QCD models of the quark-gap equation are studied in dependence of frequently employed ans\"atze for the dressed interaction and quark-gluon vertex. The explicit symmetry breaking contributions are defined by a constituent-quark sigma term whereas the combined effects of explicit and dynamical symmetry breaking are described by a Euclidean constituent-mass solution. We extend this study of the gap equation to a quark-gluon vertex beyond the Abelian approximation complemented with numerical gluon- and ghost-dressing functions from lattice QCD. We find that the ratio of the sigma term over the Euclidean mass is largely independent of nonperturbative interaction and vertex models for current-quark masses, $m_{u,d}(\mu) \leq m(\mu) \leq m_b(\mu)$, and equal contributions of explicit and dynamical chiral symmetry breaking occur at $m(\mu) \approx 400$~MeV. For massive solutions of the gap equation with lattice propagators this value decreases to about 200~MeV.
[ { "created": "Mon, 3 Dec 2018 21:58:46 GMT", "version": "v1" }, { "created": "Wed, 22 May 2019 18:25:45 GMT", "version": "v2" } ]
2019-05-29
[ [ "Serna", "Fernando E.", "" ], [ "Chen", "Chen", "" ], [ "El-Bennich", "Bruno", "" ] ]
The relative contributions of explicit and dynamical chiral symmetry breaking in QCD models of the quark-gap equation are studied in dependence of frequently employed ans\"atze for the dressed interaction and quark-gluon vertex. The explicit symmetry breaking contributions are defined by a constituent-quark sigma term whereas the combined effects of explicit and dynamical symmetry breaking are described by a Euclidean constituent-mass solution. We extend this study of the gap equation to a quark-gluon vertex beyond the Abelian approximation complemented with numerical gluon- and ghost-dressing functions from lattice QCD. We find that the ratio of the sigma term over the Euclidean mass is largely independent of nonperturbative interaction and vertex models for current-quark masses, $m_{u,d}(\mu) \leq m(\mu) \leq m_b(\mu)$, and equal contributions of explicit and dynamical chiral symmetry breaking occur at $m(\mu) \approx 400$~MeV. For massive solutions of the gap equation with lattice propagators this value decreases to about 200~MeV.
1304.6183
Eugenio Del Nobile
Eugenio Del Nobile, Graciela B. Gelmini, Paolo Gondolo, and Ji-Haeng Huh
Halo-independent analysis of direct detection data for light WIMPs
15 pages, 17 figures; v2: XENON10 bound corrected and minor changes in the text. v3: text and figures improved, accepted for publication in JCAP
null
10.1088/1475-7516/2013/10/026
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a halo-independent analysis of direct detection data on "light WIMPs," i.e. weakly interacting massive particles with mass close to or below 10 GeV/c^2. We include new results from silicon CDMS detectors (bounds and excess events), the latest CoGeNT acceptances, and recent measurements of low sodium quenching factors in NaI crystals. We focus on light WIMPs with spin-independent isospin-conserving and isospin-violating interactions with nucleons. For these dark matter candidates we find that a low quenching factor would make the DAMA modulation incompatible with a reasonable escape velocity for the dark matter halo, and that the tension among experimental data tightens in both the isospin-conserving and isospin-violating scenarios. We also find that a new although milder tension appears between the CoGeNT and DAMA annual modulations on one side and the silicon excess events on the other, in that it seems difficult to interpret them as the modulated and unmodulated aspects of the same WIMP dark matter signal.
[ { "created": "Tue, 23 Apr 2013 06:55:46 GMT", "version": "v1" }, { "created": "Thu, 25 Apr 2013 07:45:45 GMT", "version": "v2" }, { "created": "Thu, 26 Sep 2013 20:02:45 GMT", "version": "v3" } ]
2015-06-15
[ [ "Del Nobile", "Eugenio", "" ], [ "Gelmini", "Graciela B.", "" ], [ "Gondolo", "Paolo", "" ], [ "Huh", "Ji-Haeng", "" ] ]
We present a halo-independent analysis of direct detection data on "light WIMPs," i.e. weakly interacting massive particles with mass close to or below 10 GeV/c^2. We include new results from silicon CDMS detectors (bounds and excess events), the latest CoGeNT acceptances, and recent measurements of low sodium quenching factors in NaI crystals. We focus on light WIMPs with spin-independent isospin-conserving and isospin-violating interactions with nucleons. For these dark matter candidates we find that a low quenching factor would make the DAMA modulation incompatible with a reasonable escape velocity for the dark matter halo, and that the tension among experimental data tightens in both the isospin-conserving and isospin-violating scenarios. We also find that a new although milder tension appears between the CoGeNT and DAMA annual modulations on one side and the silicon excess events on the other, in that it seems difficult to interpret them as the modulated and unmodulated aspects of the same WIMP dark matter signal.
1809.02748
Nobuhito Maru
Yuki Adachi and Nobuhito Maru
Triple Higgs Boson Coupling in Gauge-Higgs Unification
10 pages, 1 figure, Additional explanation on our results added(v2)
null
null
OCU-PHYS-486
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the triple coupling of the Higgs boson in the context of the gauge-Higgs unification scenario. We show that the triple coupling of the Higgs boson in this scenario generically deviates from SM prediction since the Higgs potential in this scenario has a periodicity. We calculate the coupling in the five-dimensional $SU(3)$ x $U(1)_X$ gauge-Higgs unification model and obtain 70% deviation from the SM prediction.
[ { "created": "Sat, 8 Sep 2018 03:04:02 GMT", "version": "v1" }, { "created": "Tue, 4 Dec 2018 08:03:26 GMT", "version": "v2" } ]
2018-12-05
[ [ "Adachi", "Yuki", "" ], [ "Maru", "Nobuhito", "" ] ]
We consider the triple coupling of the Higgs boson in the context of the gauge-Higgs unification scenario. We show that the triple coupling of the Higgs boson in this scenario generically deviates from SM prediction since the Higgs potential in this scenario has a periodicity. We calculate the coupling in the five-dimensional $SU(3)$ x $U(1)_X$ gauge-Higgs unification model and obtain 70% deviation from the SM prediction.
1502.04564
Anthony Hartin
Anthony Hartin
Furry picture transition rates in the intense fields at a lepton collider interaction point
7 pages, 5 figures, Phys Lett B preprint
Phys Lett B, 743 (2015) 166-171
10.1016/j.physletb.2015.02.035
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The effect on particle physics processes by intense electromagnetic fields in the charge bunch collisions at future lepton colliders is considered. Since the charge bunch fields are tied to massive sources (the $e^{+}e^{-}$ charges), a reference frame is chosen in which the fields appear to be co-propagating. Solutions of the Dirac equation minimally coupled to the electromagnetic fields reasonably associated with two intense overlapping charge bunches are obtained and found to be a Volkov solution with respect to a null 4-vector whose 3-vector part lies in the common propagation direction. These solutions are used within the Furry interaction picture to calculate the beamstrahlung transition rate for electron radiation due to interaction with the electromagnetic fields of two colliding charge bunches. New analytic expressions are obtained and compared numerically with the beamstrahlung in the electromagnetic field of one charge bunch. The techniques developed will be applied to other collider physics processes in due course.
[ { "created": "Mon, 16 Feb 2015 15:00:53 GMT", "version": "v1" } ]
2015-03-03
[ [ "Hartin", "Anthony", "" ] ]
The effect on particle physics processes by intense electromagnetic fields in the charge bunch collisions at future lepton colliders is considered. Since the charge bunch fields are tied to massive sources (the $e^{+}e^{-}$ charges), a reference frame is chosen in which the fields appear to be co-propagating. Solutions of the Dirac equation minimally coupled to the electromagnetic fields reasonably associated with two intense overlapping charge bunches are obtained and found to be a Volkov solution with respect to a null 4-vector whose 3-vector part lies in the common propagation direction. These solutions are used within the Furry interaction picture to calculate the beamstrahlung transition rate for electron radiation due to interaction with the electromagnetic fields of two colliding charge bunches. New analytic expressions are obtained and compared numerically with the beamstrahlung in the electromagnetic field of one charge bunch. The techniques developed will be applied to other collider physics processes in due course.
1608.01850
Kirill Semenov-Tian-Shansky
Dieter M\"uller and Kirill Semenov-Tian-Shansky
On the equivalence of GPD representations
A contribution into the Proceedings of QUARKS-2016 19th International Seminar on High Energy Physics, Pushkin, Russia, 29 May - 4 June, 2016
null
10.1051/epjconf/201612504020
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Phenomenological representations of generalized parton distributions (GPDs) implementing the non-trivial field theoretical requirements are employed in the present day strategies for extracting of hadron structure information encoded in GPDs from the observables of hard exclusive reactions. Showing out the equivalence of various GPD representations can help to get more insight into GPD properties and allow to build up flexible GPD models capable of satisfactory description of the whole set of available experimental data. We review the mathematical aspects of establishing equivalence between the the double partial wave expansion of GPDs in the conformal partial waves and in the $t$-channel ${\rm SO}(3)$ partial waves and the double distribution representation of GPDs.
[ { "created": "Fri, 5 Aug 2016 12:17:01 GMT", "version": "v1" } ]
2016-11-23
[ [ "Müller", "Dieter", "" ], [ "Semenov-Tian-Shansky", "Kirill", "" ] ]
Phenomenological representations of generalized parton distributions (GPDs) implementing the non-trivial field theoretical requirements are employed in the present day strategies for extracting of hadron structure information encoded in GPDs from the observables of hard exclusive reactions. Showing out the equivalence of various GPD representations can help to get more insight into GPD properties and allow to build up flexible GPD models capable of satisfactory description of the whole set of available experimental data. We review the mathematical aspects of establishing equivalence between the the double partial wave expansion of GPDs in the conformal partial waves and in the $t$-channel ${\rm SO}(3)$ partial waves and the double distribution representation of GPDs.
hep-ph/9809480
Un-Ki Yang
U.K. Yang and A. Bodek
Parton Distributions, d/u, and Higher Twist Effects at High X
4pages, 7 figures, Talk given at 29th International Conference on High-energy Physics, Vancouver, Canada, July 1998. Submitted to Phys. Rev. Lett
Phys.Rev.Lett.82:2467-2470,1999
10.1103/PhysRevLett.82.2467
UR-1543, ER-40685-929
hep-ph hep-ex
null
A re-analysis of the NMC and SLAC data leads to a great improvement in our knowledge of the valence d and u parton distribution functions at high x. Standard parton distributions with our modifications are in good agreement with QCD predictions for d/u at x=1, and with the CDHSW nu p and nubar p data, the HERA charged current cross section data, the collider high-P_t jet data, and the CDF W asymmetry data. With the inclusion of target mass and higher twist corrections, the modified PDF's also describe all DIS data up to x = 0.98 and down to Q^2 = 1 GeV^2.
[ { "created": "Tue, 22 Sep 1998 17:35:02 GMT", "version": "v1" }, { "created": "Wed, 23 Sep 1998 02:20:18 GMT", "version": "v2" }, { "created": "Sat, 20 Feb 1999 22:01:31 GMT", "version": "v3" }, { "created": "Sat, 21 Aug 1999 18:32:36 GMT", "version": "v4" } ]
2011-02-01
[ [ "Yang", "U. K.", "" ], [ "Bodek", "A.", "" ] ]
A re-analysis of the NMC and SLAC data leads to a great improvement in our knowledge of the valence d and u parton distribution functions at high x. Standard parton distributions with our modifications are in good agreement with QCD predictions for d/u at x=1, and with the CDHSW nu p and nubar p data, the HERA charged current cross section data, the collider high-P_t jet data, and the CDF W asymmetry data. With the inclusion of target mass and higher twist corrections, the modified PDF's also describe all DIS data up to x = 0.98 and down to Q^2 = 1 GeV^2.
1305.5715
Daren Zhou
Daren Zhou, Rob G. E. Timmermans
Polarization observables in low-energy antiproton-proton scattering
null
Phys. Rev. C 87, 054005 (2013)
10.1103/PhysRevC.87.054005
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the polarization parameters in low-energy antiproton-proton elastic ($\bar{p}p\rightarrow\bar{p}p$) and charge-exchange ($\bar{p}p\rightarrow\bar{n}n$) scattering. The predictions for unmeasured observables are based on our new energy-dependent partial-wave analysis of all antiproton-proton scattering data below 925 MeV/$c$ antiproton laboratory momentum, which gives an optimal description of the existing database. Sizable and remarkable spin effects are observed, in particular for charge-exchange scattering. These result from the spin dependence of the long- and medium-range one- and two-pion exchange antinucleon-nucleon potential and the state dependence of the parametrized short-range interaction. We study the possibility of polarizing a circulating antiproton beam with a polarized proton target by exploiting the spin dependence of the $\bar{p}p$ total cross section. It appears feasible to achieve a significant transverse polarization of an antiproton beam within a reasonable time.
[ { "created": "Fri, 24 May 2013 12:48:37 GMT", "version": "v1" } ]
2013-05-27
[ [ "Zhou", "Daren", "" ], [ "Timmermans", "Rob G. E.", "" ] ]
We investigate the polarization parameters in low-energy antiproton-proton elastic ($\bar{p}p\rightarrow\bar{p}p$) and charge-exchange ($\bar{p}p\rightarrow\bar{n}n$) scattering. The predictions for unmeasured observables are based on our new energy-dependent partial-wave analysis of all antiproton-proton scattering data below 925 MeV/$c$ antiproton laboratory momentum, which gives an optimal description of the existing database. Sizable and remarkable spin effects are observed, in particular for charge-exchange scattering. These result from the spin dependence of the long- and medium-range one- and two-pion exchange antinucleon-nucleon potential and the state dependence of the parametrized short-range interaction. We study the possibility of polarizing a circulating antiproton beam with a polarized proton target by exploiting the spin dependence of the $\bar{p}p$ total cross section. It appears feasible to achieve a significant transverse polarization of an antiproton beam within a reasonable time.
1811.05002
Daisuke Hagihara
Daisuke Hagihara, Koichi Hamaguchi and Kazunori Nakayama
Moduli Oscillation Induced by Reheating
26 pages, 5 figures, 1 table; v2: version published in JCAP
JCAP03(2019)024
10.1088/1475-7516/2019/03/024
UT-18-26, IPMU18-0188
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We estimate the abundance of the coherent oscillation of moduli, which linearly couple to matter fields through higher dimensional operators. During the (p)reheating after inflation, matter particles are efficiently produced and it can affect the moduli potential in a non-adiabatic way, which results in the coherent oscillation of the moduli. In particular, such effects are most important at the very beginning of the (p)reheating. It is found that this production mechanism is so efficient that a successful evolution of the universe can be threatened even if the moduli mass is larger than the Hubble scale.
[ { "created": "Mon, 12 Nov 2018 21:06:11 GMT", "version": "v1" }, { "created": "Fri, 15 Mar 2019 08:59:11 GMT", "version": "v2" } ]
2019-03-18
[ [ "Hagihara", "Daisuke", "" ], [ "Hamaguchi", "Koichi", "" ], [ "Nakayama", "Kazunori", "" ] ]
We estimate the abundance of the coherent oscillation of moduli, which linearly couple to matter fields through higher dimensional operators. During the (p)reheating after inflation, matter particles are efficiently produced and it can affect the moduli potential in a non-adiabatic way, which results in the coherent oscillation of the moduli. In particular, such effects are most important at the very beginning of the (p)reheating. It is found that this production mechanism is so efficient that a successful evolution of the universe can be threatened even if the moduli mass is larger than the Hubble scale.
2111.07076
Jason Aebischer
Jason Aebischer, Benjam\'in Grinstein
The $B_c$ lifetime in the Standard Model
5 pages, Contribution to the proceedings of the 22nd Particles and Nuclei International Conference (PANIC21), 5-10 September 2021
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using an operator product expansion (OPE) approach an updated Standard Model prediction of the $B_c$ lifetime is presented. The computation in three different mass schemes for the heavy quarks leads to three different values consistent with each other and with experiment. Furthermore a novel way to compute the $B_c$ lifetime is presented, taking differences of $B,D$ and $B_c$ meson decay rates. In this approach the leading contributions from free-quark decays cancel out, leading to a reduction of scale and scheme dependence.
[ { "created": "Sat, 13 Nov 2021 09:41:40 GMT", "version": "v1" } ]
2021-11-16
[ [ "Aebischer", "Jason", "" ], [ "Grinstein", "Benjamín", "" ] ]
Using an operator product expansion (OPE) approach an updated Standard Model prediction of the $B_c$ lifetime is presented. The computation in three different mass schemes for the heavy quarks leads to three different values consistent with each other and with experiment. Furthermore a novel way to compute the $B_c$ lifetime is presented, taking differences of $B,D$ and $B_c$ meson decay rates. In this approach the leading contributions from free-quark decays cancel out, leading to a reduction of scale and scheme dependence.
2103.04605
Wangmei Zha
Wangmei Zha, Zebo Tang
Discovery of higher order QED effect for the vacuum pair production
null
null
10.1007/JHEP08(2021)083
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The higher order quantum electrodynamics (QED) effect for vacuum pair production has been searched without success since 1954. In this paper, we show that the lowest order QED calculations for lepton pair vacuum production in heavy-ion collisions are about 20$\%$ higher than the combined world-wide data with a seven sigma-level of significance and the corresponding higher order QED results are consistent with data. We claim the discovery of higher order effect for the QED pair production, which settles the dust of previous debates for several decades. The verification of higher order QED effect is a fundamental scientific problem, which is an important milestone towards the nonperturbative and nonlinear regime of QED vacuum.
[ { "created": "Mon, 8 Mar 2021 08:55:22 GMT", "version": "v1" } ]
2021-09-15
[ [ "Zha", "Wangmei", "" ], [ "Tang", "Zebo", "" ] ]
The higher order quantum electrodynamics (QED) effect for vacuum pair production has been searched without success since 1954. In this paper, we show that the lowest order QED calculations for lepton pair vacuum production in heavy-ion collisions are about 20$\%$ higher than the combined world-wide data with a seven sigma-level of significance and the corresponding higher order QED results are consistent with data. We claim the discovery of higher order effect for the QED pair production, which settles the dust of previous debates for several decades. The verification of higher order QED effect is a fundamental scientific problem, which is an important milestone towards the nonperturbative and nonlinear regime of QED vacuum.
1112.5155
Mathias Garny
Mathias Garny, Alejandro Ibarra, Stefan Vogl
Dark matter annihilations into two light fermions and one gauge boson: general analysis and antiproton constraints
39 pages, 10 figures; v2: minor changes, matches published version; v3: typo corrected
null
10.1088/1475-7516/2012/04/033
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study in this paper the scenario where the dark matter is constituted by Majorana particles which couple to a light Standard Model fermion and an extra scalar via a Yukawa coupling. In this scenario, the annihilation rate into the light fermions with the mediation of the scalar particle is strongly suppressed by the mass of the fermion. Nevertheless, the helicity suppression is lifted by the associated emission of a gauge boson, yielding annihilation rates which could be large enough to allow the indirect detection of the dark matter particles. We perform a general analysis of this scenario, calculating the annihilation cross section of the processes \chi\chi\rightarrow f\bar f V when the dark matter particle is a SU(2)_L singlet or doublet, f is a lepton or a quark, and V is a photon, a weak gauge boson or a gluon. We point out that the annihilation rate is particularly enhanced when the dark matter particle is degenerate in mass to the intermediate scalar particle, which is a scenario barely constrained by collider searches of exotic charged or colored particles. Lastly, we derive upper limits on the relevant cross sections from the non-observation of an excess in the cosmic antiproton-to-proton ratio measured by PAMELA.
[ { "created": "Wed, 21 Dec 2011 20:57:28 GMT", "version": "v1" }, { "created": "Mon, 23 Apr 2012 09:28:24 GMT", "version": "v2" }, { "created": "Thu, 11 Jul 2013 17:14:35 GMT", "version": "v3" } ]
2015-06-03
[ [ "Garny", "Mathias", "" ], [ "Ibarra", "Alejandro", "" ], [ "Vogl", "Stefan", "" ] ]
We study in this paper the scenario where the dark matter is constituted by Majorana particles which couple to a light Standard Model fermion and an extra scalar via a Yukawa coupling. In this scenario, the annihilation rate into the light fermions with the mediation of the scalar particle is strongly suppressed by the mass of the fermion. Nevertheless, the helicity suppression is lifted by the associated emission of a gauge boson, yielding annihilation rates which could be large enough to allow the indirect detection of the dark matter particles. We perform a general analysis of this scenario, calculating the annihilation cross section of the processes \chi\chi\rightarrow f\bar f V when the dark matter particle is a SU(2)_L singlet or doublet, f is a lepton or a quark, and V is a photon, a weak gauge boson or a gluon. We point out that the annihilation rate is particularly enhanced when the dark matter particle is degenerate in mass to the intermediate scalar particle, which is a scenario barely constrained by collider searches of exotic charged or colored particles. Lastly, we derive upper limits on the relevant cross sections from the non-observation of an excess in the cosmic antiproton-to-proton ratio measured by PAMELA.
hep-ph/0107304
Alon Faraggi
Claudio Coriano, Alon E. Faraggi
SUSY Scaling Violations and UHECR
7 pages. 3 figures. Presented by C. Coriano at the Intl. Workshop ``QCD @ work'', Martina Franca, Italy 16-20 June 2001
AIP Conf.Proc. 602 (2001) 145-149
10.1063/1.1435922
OUTP-01-40P; UNILE-CBR-2001-5
hep-ph astro-ph hep-th
null
Advancing QCD toward astroparticle applications generates new challenges for perturbation theory, such as the presence of large evolution scales with sizeable scaling violations involving both the initial and the final state of a collision. Possible applications in the context of Ultra High Energy Cosmic Rays (UHECR) of these effects are discussed.
[ { "created": "Mon, 30 Jul 2001 14:31:22 GMT", "version": "v1" } ]
2009-11-07
[ [ "Coriano", "Claudio", "" ], [ "Faraggi", "Alon E.", "" ] ]
Advancing QCD toward astroparticle applications generates new challenges for perturbation theory, such as the presence of large evolution scales with sizeable scaling violations involving both the initial and the final state of a collision. Possible applications in the context of Ultra High Energy Cosmic Rays (UHECR) of these effects are discussed.
0801.1939
Mojtaba Mohammadi Najafabadi
Mojtaba Mohammadi Najafabadi
Probing of $Wtb$ Anomalous Couplings via the $tW$ Channel of Single Top Production
11 pages, 4 figures
JHEP 0803:024,2008
10.1088/1126-6708/2008/03/024
null
hep-ph
null
The potential of LHC for investigation of the $W$-$t$-$b$ vertex through the $tW$ channel of single top quark production is studied. Unlike the other two single top quark production processes ($t-$channel and $s-$channel), the $tW$ channel provides the possibility to study the $Wtb$ vertex without receiving contamination from FCNC. This study has been done at parton level but is involved the separation of signal from backgrounds when both $W$-bosons decay to leptons. In this study $\mathcal{CP}$ is assumed to be conserved. The 68% C.L. bounds on the non-Standard Model couplings are estimated.
[ { "created": "Sun, 13 Jan 2008 07:14:01 GMT", "version": "v1" }, { "created": "Mon, 18 Feb 2008 09:03:34 GMT", "version": "v2" }, { "created": "Sun, 16 Mar 2008 08:25:09 GMT", "version": "v3" } ]
2009-01-06
[ [ "Najafabadi", "Mojtaba Mohammadi", "" ] ]
The potential of LHC for investigation of the $W$-$t$-$b$ vertex through the $tW$ channel of single top quark production is studied. Unlike the other two single top quark production processes ($t-$channel and $s-$channel), the $tW$ channel provides the possibility to study the $Wtb$ vertex without receiving contamination from FCNC. This study has been done at parton level but is involved the separation of signal from backgrounds when both $W$-bosons decay to leptons. In this study $\mathcal{CP}$ is assumed to be conserved. The 68% C.L. bounds on the non-Standard Model couplings are estimated.
hep-ph/0308098
Jozef Dudek
F.E. Close & J.J. Dudek
Hybrid meson production by electromagnetic and weak interactions in a flux-tube simulation of lattice QCD
uses psfrag; One reference corrected
Phys.Rev.D69:034010,2004
10.1103/PhysRevD.69.034010
null
hep-ph
null
We calculate rates for hybrid meson production by electromagnetic and weak interactions in the flux-tube model. Applications include photo and electroproduction at Jefferson Laboratory and HERA, and the production of light strange and charmed hybrids in the weak decays of heavy flavours. Photoproduction of some light hybrids is predicted to be prominent in charge exchange reactions, $\gamma p \to n \cal{H}$ and accessible in $\gamma p \to p \cal{H}$. Production of light or charmed hybrids in $B$ and $D$ decays may be feasible with high statistics. Photoproduction of the axial hybrid meson is predicted to be large courtesy of $\pi$ exchange, and its strange counterpart is predicted in $B \to \psi K_H(1^+)$ with $b.r. \sim 10^{-4}$. Production rates for exotic hybrid candidates $1^{-+};(0,2)^{+-}$ are given special attention. Selection rules that can help to distinguish between hybrid and conventional states with the same $J^{PC}$ are noted.
[ { "created": "Fri, 8 Aug 2003 10:38:11 GMT", "version": "v1" }, { "created": "Mon, 11 Aug 2003 13:24:57 GMT", "version": "v2" } ]
2008-11-26
[ [ "Close", "F. E.", "" ], [ "Dudek", "J. J.", "" ] ]
We calculate rates for hybrid meson production by electromagnetic and weak interactions in the flux-tube model. Applications include photo and electroproduction at Jefferson Laboratory and HERA, and the production of light strange and charmed hybrids in the weak decays of heavy flavours. Photoproduction of some light hybrids is predicted to be prominent in charge exchange reactions, $\gamma p \to n \cal{H}$ and accessible in $\gamma p \to p \cal{H}$. Production of light or charmed hybrids in $B$ and $D$ decays may be feasible with high statistics. Photoproduction of the axial hybrid meson is predicted to be large courtesy of $\pi$ exchange, and its strange counterpart is predicted in $B \to \psi K_H(1^+)$ with $b.r. \sim 10^{-4}$. Production rates for exotic hybrid candidates $1^{-+};(0,2)^{+-}$ are given special attention. Selection rules that can help to distinguish between hybrid and conventional states with the same $J^{PC}$ are noted.
hep-ph/9808403
Cosmin Macesanu
C. Macesanu, L. H. Orr
Gluon Radiation in Top Quark Production and Decay at an e^+ e^- Collider
9 pages, LaTeX, 6 postscript figures, uses aipproc.sty; presented at the 20th annual MRST meeting on High-Energy Physics, Montreal, Canada, 13-15 May 1998
null
10.1063/1.57081
UR-1542
hep-ph
null
We study the effects of gluon radiation on top production and decay processes at an $e^+e^-$ collider.The matrix elements are computed without any approximations, using spinor techniques. We use a Monte Carlo event generator which takes into account the infrared singularity due to soft gluons and differences in kinematics associated with radiation in the production versus decay process. The calculation is illustrated for several strategies of top mass reconstruction.
[ { "created": "Mon, 24 Aug 1998 20:14:06 GMT", "version": "v1" } ]
2009-10-31
[ [ "Macesanu", "C.", "" ], [ "Orr", "L. H.", "" ] ]
We study the effects of gluon radiation on top production and decay processes at an $e^+e^-$ collider.The matrix elements are computed without any approximations, using spinor techniques. We use a Monte Carlo event generator which takes into account the infrared singularity due to soft gluons and differences in kinematics associated with radiation in the production versus decay process. The calculation is illustrated for several strategies of top mass reconstruction.
hep-ph/9311323
Stephan
F. J. Yndurain
On the Evaluation of Threshold Effects in Processes Involving Heavy Quarks
12 pages, preprint FTUAM 38/93
Phys.Lett.B321:400-406,1994
10.1016/0370-2693(94)90266-6
null
hep-ph
null
A detailed evaluation is presented of production of heavy fermions (particularly ttbar quarks) by a vector current, in the region around threshold. This includes bound states as well as the region above threshold, to the same degree of accuracy; in both cases radiative and nonperturbative corrections are included. The contribution of this region to the vacuum polarization (``threshold effects'') is calculated and compared with a perturbative calculation; the importance of the threshold effects is found substantially smaller than claimed by some authors. Open fermion-antifermion production is also discussed.
[ { "created": "Sat, 20 Nov 1993 18:16:06 GMT", "version": "v1" } ]
2010-11-01
[ [ "Yndurain", "F. J.", "" ] ]
A detailed evaluation is presented of production of heavy fermions (particularly ttbar quarks) by a vector current, in the region around threshold. This includes bound states as well as the region above threshold, to the same degree of accuracy; in both cases radiative and nonperturbative corrections are included. The contribution of this region to the vacuum polarization (``threshold effects'') is calculated and compared with a perturbative calculation; the importance of the threshold effects is found substantially smaller than claimed by some authors. Open fermion-antifermion production is also discussed.
hep-ph/0009141
Hidekazu Yokomakura
H. Yokomakura, K. Kimura, A. Takamura
Matter Enhancement of T Violation in Neutrino Oscillation
11 pages, 10 figures, corrected some typos
Phys.Lett. B496 (2000) 175-184
10.1016/S0370-2693(00)01288-0
DPNU-00-30
hep-ph
null
We study the matter enhancement of T violation in neutrino oscillation with three generations. The magnitude of T violation is proportional to Jarlskog factor J. Recently, the elegant relation, (\Delta_m)_{12}(\Delta_m)_{23}(\Delta_m)_{31}J_{m} = \Delta_{12}\Delta_{23}\Delta_{31}J, was derived, where \Delta_{ij}=\Delta m^2_{ij}/(2E) and subscript m implies the quantities in matter. Using this relation, we reconsider how J_m changes as a function of the matter potential a under the approximation |\Delta m^2_{12}| \ll |\Delta m^2_{13}|. We show that the number of maxima for J_{m} depends on the magnitude of \sin^2 2 \theta_{13} and there are two maxima considering the constraint on \sin^2 2\theta_{13} from the CHOOZ experiment. One maximum of $J_{m} at a = O(\Delta_{12}) is given by J/\sin2\theta_{12}, which leads to the large enhancement of J_m in the case of the SMA MSW solution. The other maximum at a = O(\Delta_{13}) is |\Delta_{12}/\Delta_{13}|J/\sin2\theta_{13}, and the enhancement is possible, if \sin 2 \theta_{13} is small enough. These maximal values are consistent with the results obtained by other methods.
[ { "created": "Tue, 12 Sep 2000 13:28:31 GMT", "version": "v1" }, { "created": "Fri, 3 May 2002 12:13:46 GMT", "version": "v2" } ]
2009-10-31
[ [ "Yokomakura", "H.", "" ], [ "Kimura", "K.", "" ], [ "Takamura", "A.", "" ] ]
We study the matter enhancement of T violation in neutrino oscillation with three generations. The magnitude of T violation is proportional to Jarlskog factor J. Recently, the elegant relation, (\Delta_m)_{12}(\Delta_m)_{23}(\Delta_m)_{31}J_{m} = \Delta_{12}\Delta_{23}\Delta_{31}J, was derived, where \Delta_{ij}=\Delta m^2_{ij}/(2E) and subscript m implies the quantities in matter. Using this relation, we reconsider how J_m changes as a function of the matter potential a under the approximation |\Delta m^2_{12}| \ll |\Delta m^2_{13}|. We show that the number of maxima for J_{m} depends on the magnitude of \sin^2 2 \theta_{13} and there are two maxima considering the constraint on \sin^2 2\theta_{13} from the CHOOZ experiment. One maximum of $J_{m} at a = O(\Delta_{12}) is given by J/\sin2\theta_{12}, which leads to the large enhancement of J_m in the case of the SMA MSW solution. The other maximum at a = O(\Delta_{13}) is |\Delta_{12}/\Delta_{13}|J/\sin2\theta_{13}, and the enhancement is possible, if \sin 2 \theta_{13} is small enough. These maximal values are consistent with the results obtained by other methods.
0906.3417
Giacomo Cacciapaglia
Giacomo Cacciapaglia, Aldo Deandrea (IPN Lyon) and Stefania De Curtis (INFN Firenze)
Nearby resonances beyond the Breit-Wigner approximation
14 pages, 3 figures
Phys.Lett.B682:43-49,2009
10.1016/j.physletb.2009.10.090
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a description of propagators for particle resonances which takes into account the quantum mechanical interference due to the width of two or more nearby states that have common decay channels, by incorporating the effects arising from the imaginary parts of the one-loop self-energies. Depending on the couplings to the common decay channels, the interference effect, not taken into account in the usual Breit-Wigner approximation, can significantly modify the cross section or make the more long-lived resonance narrower. We give few examples of New Physics models for which the effect is sizable, namely a generic two and multiple Higgs model and neutral vector resonances in Higgsless models. Based on these results we suggest the implementation of a proper treatment of nearby resonances into Monte Carlo generators.
[ { "created": "Thu, 18 Jun 2009 13:38:35 GMT", "version": "v1" }, { "created": "Thu, 29 Oct 2009 13:58:05 GMT", "version": "v2" } ]
2009-11-18
[ [ "Cacciapaglia", "Giacomo", "", "IPN Lyon" ], [ "Deandrea", "Aldo", "", "IPN Lyon" ], [ "De Curtis", "Stefania", "", "INFN Firenze" ] ]
We consider a description of propagators for particle resonances which takes into account the quantum mechanical interference due to the width of two or more nearby states that have common decay channels, by incorporating the effects arising from the imaginary parts of the one-loop self-energies. Depending on the couplings to the common decay channels, the interference effect, not taken into account in the usual Breit-Wigner approximation, can significantly modify the cross section or make the more long-lived resonance narrower. We give few examples of New Physics models for which the effect is sizable, namely a generic two and multiple Higgs model and neutral vector resonances in Higgsless models. Based on these results we suggest the implementation of a proper treatment of nearby resonances into Monte Carlo generators.
1208.5527
Chi-Sing Lam
C. S. Lam
Finite Symmetry of Leptonic Mass Matrices
Version to appear in Physical Review D
null
10.1103/PhysRevD.87.013001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We search for possible symmetries present in the leptonic mixing data from SU(3) subgroups of order up to 511. Theoretical results based on symmetry are compared with global fits of experimental data in a chi-squared analysis, yielding the following results. There is no longer a group that can produce all the mixing data without a free parameter, but a number of them can accommodate the first or the second column of the mixing matrix. The only group that fits the third column is $\Delta(150)$. It predicts $\sin^22\theta_{13}=0.11$ and $\sin^22\theta_{23}=0.94$, in good agreement with experimental results.
[ { "created": "Mon, 27 Aug 2012 22:49:57 GMT", "version": "v1" }, { "created": "Sun, 16 Dec 2012 05:09:23 GMT", "version": "v2" } ]
2015-06-11
[ [ "Lam", "C. S.", "" ] ]
We search for possible symmetries present in the leptonic mixing data from SU(3) subgroups of order up to 511. Theoretical results based on symmetry are compared with global fits of experimental data in a chi-squared analysis, yielding the following results. There is no longer a group that can produce all the mixing data without a free parameter, but a number of them can accommodate the first or the second column of the mixing matrix. The only group that fits the third column is $\Delta(150)$. It predicts $\sin^22\theta_{13}=0.11$ and $\sin^22\theta_{23}=0.94$, in good agreement with experimental results.
1211.2818
Yiming Xu
A. Liam Fitzpatrick, Wick Haxton, Emanuel Katz, Nicholas Lubbers, Yiming Xu
Model Independent Direct Detection Analyses
25 pages, 11 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Following the construction of the general effective theory for dark matter direct detection in 1203.3542, we perform an analysis of the experimental constraints on the full parameter space of elastically scattering dark matter. We review the prescription for calculating event rates in the general effective theory and discuss the sensitivity of various experiments to additional nuclear responses beyond the spin-independent (SI) and spin-dependent (SD) couplings: an angular-momentum-dependent (LD) and spin-and-angular-momentum-dependent (LSD) response, as well as a distinction between transverse and longitudinal spin-dependent responses. We consider the effect of interference between different operators and in particular look at directions in parameter space where such cancellations lead to holes in the sensitivity of individual experiments. We explore the complementarity of different experiments by looking at the improvement of bounds when experiments are combined. Finally, our scan through parameter space shows that within the assumptions on models and on the experiments' sensitivity that we make, no elastically scattering dark matter explanation of DAMA is consistent with all other experiments at 90%, though we find points in parameter space that are ruled out only by about a factor of 2 in the cross-section.
[ { "created": "Mon, 12 Nov 2012 21:00:28 GMT", "version": "v1" } ]
2012-11-14
[ [ "Fitzpatrick", "A. Liam", "" ], [ "Haxton", "Wick", "" ], [ "Katz", "Emanuel", "" ], [ "Lubbers", "Nicholas", "" ], [ "Xu", "Yiming", "" ] ]
Following the construction of the general effective theory for dark matter direct detection in 1203.3542, we perform an analysis of the experimental constraints on the full parameter space of elastically scattering dark matter. We review the prescription for calculating event rates in the general effective theory and discuss the sensitivity of various experiments to additional nuclear responses beyond the spin-independent (SI) and spin-dependent (SD) couplings: an angular-momentum-dependent (LD) and spin-and-angular-momentum-dependent (LSD) response, as well as a distinction between transverse and longitudinal spin-dependent responses. We consider the effect of interference between different operators and in particular look at directions in parameter space where such cancellations lead to holes in the sensitivity of individual experiments. We explore the complementarity of different experiments by looking at the improvement of bounds when experiments are combined. Finally, our scan through parameter space shows that within the assumptions on models and on the experiments' sensitivity that we make, no elastically scattering dark matter explanation of DAMA is consistent with all other experiments at 90%, though we find points in parameter space that are ruled out only by about a factor of 2 in the cross-section.
0906.2950
Pavel Fileviez Perez
Pavel Fileviez Perez, Mark B. Wise
On the Origin of Neutrino Masses
9 pages, minor corrections and typos corrected
Phys.Rev.D80:053006,2009
10.1103/PhysRevD.80.053006
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the simplest mechanisms for generating neutrino masses at tree level and one loop level. We find a significant number of new possibilities where one can generate neutrino masses at the one-loop level by adding only two new types of representations. These models have renormalizable interactions that automatically conserve baryon number. Adding to the minimal standard model a scalar color octet with SU(3) X SU(2) X U(1) quantum numbers, (8,2,1/2), and a fermionic color octet in the fundamental or adjoint representation of SU(2) one can generate neutrino masses in agreement with the experiment. Signals at the LHC, and constraints from flavour violation are briefly discussed.
[ { "created": "Tue, 16 Jun 2009 16:03:38 GMT", "version": "v1" }, { "created": "Wed, 24 Jun 2009 21:21:18 GMT", "version": "v2" } ]
2009-09-09
[ [ "Perez", "Pavel Fileviez", "" ], [ "Wise", "Mark B.", "" ] ]
We discuss the simplest mechanisms for generating neutrino masses at tree level and one loop level. We find a significant number of new possibilities where one can generate neutrino masses at the one-loop level by adding only two new types of representations. These models have renormalizable interactions that automatically conserve baryon number. Adding to the minimal standard model a scalar color octet with SU(3) X SU(2) X U(1) quantum numbers, (8,2,1/2), and a fermionic color octet in the fundamental or adjoint representation of SU(2) one can generate neutrino masses in agreement with the experiment. Signals at the LHC, and constraints from flavour violation are briefly discussed.
hep-ph/9701263
Antonio Pich
A. Pich
Lepton Universality
21 pages, latex, 6 Postscript figures, Lectures at the Cargese'96 School --Masses of Fundamental Particles-- (Cargese, Corsica, 5-17 August 1996
NATO Adv.Study Inst.Ser.B Phys.363:173-190,1997
null
FTUV/97-02, IFIC/97-02
hep-ph
null
The Standard Model requires the three known leptonic families to have identical couplings to the gauge bosons. The present experimental tests on lepton universality are reviewed, both for the charged and neutral current sectors. Our knowledge about the Lorentz structure of the $l^-\to\nu_l l'^-\bar\nu_{l'}$ transition amplitudes is also discussed.
[ { "created": "Fri, 10 Jan 1997 13:43:26 GMT", "version": "v1" } ]
2009-02-16
[ [ "Pich", "A.", "" ] ]
The Standard Model requires the three known leptonic families to have identical couplings to the gauge bosons. The present experimental tests on lepton universality are reviewed, both for the charged and neutral current sectors. Our knowledge about the Lorentz structure of the $l^-\to\nu_l l'^-\bar\nu_{l'}$ transition amplitudes is also discussed.
1310.5414
Xu Qingjun
Qing-jun Xu, Shu-sheng Xu, Zhen-jun Xiao and Li-gang Jin
The loop effects on the chargino decays $\tilde{\chi}_1^\pm\to \tilde{\chi}_1^0 f f^\prime$ in the MSSM
13 pages, 3 figures
null
10.1007/s11434-014-0289-3
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The lighter chargino three body decays $\tilde{\chi}_1^\pm\to \tilde{\chi}_1^0 f f^\prime$ via the $W^\pm$ boson and the charged Higgs boson $H^\pm$ are studied in the R-parity conserved Minimal Supersymmetric Standard Model (MSSM). We treat $\tilde \chi_1^\pm$ decays as production and decay of $W^\pm$ and $H^\pm$: i.e., $\tilde{\chi}_1^\pm \to \tilde{\chi}_1^0 W^\pm (H^\pm) \to \tilde{\chi}_1^0 f f^\prime$. Both higgsino-like and wino-like $\tilde \chi_1^\pm$ decays are well investigated. These decays are calculated at 1-loop level and the loop corrections are found to be less than three percent.The signal of the charged Higgs $H^\pm$ production from $\tilde \chi_1^\pm$ decays are discussed. It will offer important information about the chargino and neutralino sector, as well as the charged Higgs sector in the MSSM.
[ { "created": "Mon, 21 Oct 2013 03:45:33 GMT", "version": "v1" }, { "created": "Sun, 8 Dec 2013 15:10:19 GMT", "version": "v2" } ]
2014-04-23
[ [ "Xu", "Qing-jun", "" ], [ "Xu", "Shu-sheng", "" ], [ "Xiao", "Zhen-jun", "" ], [ "Jin", "Li-gang", "" ] ]
The lighter chargino three body decays $\tilde{\chi}_1^\pm\to \tilde{\chi}_1^0 f f^\prime$ via the $W^\pm$ boson and the charged Higgs boson $H^\pm$ are studied in the R-parity conserved Minimal Supersymmetric Standard Model (MSSM). We treat $\tilde \chi_1^\pm$ decays as production and decay of $W^\pm$ and $H^\pm$: i.e., $\tilde{\chi}_1^\pm \to \tilde{\chi}_1^0 W^\pm (H^\pm) \to \tilde{\chi}_1^0 f f^\prime$. Both higgsino-like and wino-like $\tilde \chi_1^\pm$ decays are well investigated. These decays are calculated at 1-loop level and the loop corrections are found to be less than three percent.The signal of the charged Higgs $H^\pm$ production from $\tilde \chi_1^\pm$ decays are discussed. It will offer important information about the chargino and neutralino sector, as well as the charged Higgs sector in the MSSM.
hep-ph/9209297
null
C.J. Fewster and B.S. Kay
Model Dependence of Baryon Decay Enhancement by Cosmic Strings
20 pages, LaTeX, DAMTP-R92/28
Nucl.Phys.B399:89-110,1993
10.1016/0550-3213(93)90618-Y
null
hep-ph hep-th
null
Cosmic strings arising from GUTs can catalyse baryon decay processes with strong interaction cross sections. We examine the mechanism by which the cross section is enhanced and find that it depends strongly on the details of the distribution of gauge fields within the string core. We propose a calculational scheme for estimating wavefunction amplification factors and also a physical understanding of the nature of the enhancement process.
[ { "created": "Wed, 30 Sep 1992 11:26:41 GMT", "version": "v1" } ]
2008-11-26
[ [ "Fewster", "C. J.", "" ], [ "Kay", "B. S.", "" ] ]
Cosmic strings arising from GUTs can catalyse baryon decay processes with strong interaction cross sections. We examine the mechanism by which the cross section is enhanced and find that it depends strongly on the details of the distribution of gauge fields within the string core. We propose a calculational scheme for estimating wavefunction amplification factors and also a physical understanding of the nature of the enhancement process.