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hep-ph/0602078
Alexander Smirnov
A.V. Smirnov
An Algorithm to Construct Groebner Bases for Solving Integration by Parts Relations
LaTeX, 9 pages
JHEP 0604 (2006) 026
10.1088/1126-6708/2006/04/026
null
hep-ph hep-th
null
This paper is a detailed description of an algorithm based on a generalized Buchberger algorithm for constructing Groebner-type bases associated with polynomials of shift operators. The algorithm is used for calculating Feynman integrals and has proven itself efficient in several complicated cases.
[ { "created": "Thu, 9 Feb 2006 10:08:40 GMT", "version": "v1" } ]
2009-11-11
[ [ "Smirnov", "A. V.", "" ] ]
This paper is a detailed description of an algorithm based on a generalized Buchberger algorithm for constructing Groebner-type bases associated with polynomials of shift operators. The algorithm is used for calculating Feynman integrals and has proven itself efficient in several complicated cases.
hep-ph/0607317
Bilenky Samoil
S. M. Bilenky
Status of Neutrino Masses and Mixing and Future Perspectives
Report at the conference IRGAC 2006, Barcelona July 11-15 2006
J.Phys.A40:6707-6714,2007
10.1088/1751-8113/40/25/S15
null
hep-ph
null
Status of the problem of neutrino masses, mixing and oscillations is discussed. Future perspectives are briefly considered.
[ { "created": "Fri, 28 Jul 2006 13:29:06 GMT", "version": "v1" } ]
2008-11-26
[ [ "Bilenky", "S. M.", "" ] ]
Status of the problem of neutrino masses, mixing and oscillations is discussed. Future perspectives are briefly considered.
1806.01310
Estela A. Garces
B. C. Ca\~nas, E. A. Garc\'es, O. G. Miranda and A. Parada
Future perspectives for a weak mixing angle measurement in coherent elastic neutrino nucleus scattering experiments
11 pages, 3 figures (contains subfigures) and two tables. References added. Accepted for publication in PLB
null
10.1016/j.physletb.2018.07.049
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
After the first measurement of the coherent elastic neutrino nucleus scattering (CENNS) by the COHERENT Collaboration, it is expected that new experiments will confirm the observation. Such measurements will allow to put stronger constraints or discover new physics as well as to probe the Standard Model by measuring its parameters. This is the case of the weak mixing angle at low energies, which could be measured with an increased precision in future results of CENNS experiments using, for example, reactor antineutrinos. In this work we analyze the physics potential of different proposals for the improvement of our current knowledge of this observable and show that they are very promising.
[ { "created": "Mon, 4 Jun 2018 18:18:07 GMT", "version": "v1" }, { "created": "Sat, 28 Jul 2018 15:59:53 GMT", "version": "v2" } ]
2018-08-01
[ [ "Cañas", "B. C.", "" ], [ "Garcés", "E. A.", "" ], [ "Miranda", "O. G.", "" ], [ "Parada", "A.", "" ] ]
After the first measurement of the coherent elastic neutrino nucleus scattering (CENNS) by the COHERENT Collaboration, it is expected that new experiments will confirm the observation. Such measurements will allow to put stronger constraints or discover new physics as well as to probe the Standard Model by measuring its parameters. This is the case of the weak mixing angle at low energies, which could be measured with an increased precision in future results of CENNS experiments using, for example, reactor antineutrinos. In this work we analyze the physics potential of different proposals for the improvement of our current knowledge of this observable and show that they are very promising.
hep-ph/9405268
Jicai Pan
Rudolph C. Hwa and Jicai Pan
Cluster Growth in Two-Dimensional Quark-Hadron Phase Transition
14 pages, 9 postscript figures included
Phys.Rev.C50:2516-2524,1994
10.1103/PhysRevC.50.2516
null
hep-ph
null
The problem of hadronic cluster production in heavy-ion collisions is studied in search for an observable signature of first-order quark-hadron phase transition. The study is carried out by cellular automata in a two-dimensional model of the mixed phase at midrapidity. The clusters are allowed to grow as well as to coalesce upon collision. The distribution of cluster sizes is found to exhibit scaling behavior that is independent of the size of the mixed region, nucleation radius and nucleation probability. The universal scaling index $\gamma=1.86\pm 0.18$ may be used to characterize and identify the phase transition process. Possible connection with self-organized criticality is pointed out.
[ { "created": "Wed, 11 May 1994 16:39:44 GMT", "version": "v1" } ]
2009-09-25
[ [ "Hwa", "Rudolph C.", "" ], [ "Pan", "Jicai", "" ] ]
The problem of hadronic cluster production in heavy-ion collisions is studied in search for an observable signature of first-order quark-hadron phase transition. The study is carried out by cellular automata in a two-dimensional model of the mixed phase at midrapidity. The clusters are allowed to grow as well as to coalesce upon collision. The distribution of cluster sizes is found to exhibit scaling behavior that is independent of the size of the mixed region, nucleation radius and nucleation probability. The universal scaling index $\gamma=1.86\pm 0.18$ may be used to characterize and identify the phase transition process. Possible connection with self-organized criticality is pointed out.
hep-ph/9902238
Amir Fariborz
Amir H. Fariborz and Joseph Schechter
eta' to eta pi pi Decay as a Probe of a Possible Lowest-Lying Scalar Nonet
25 pages, 11 figures
Phys.Rev. D60 (1999) 034002
10.1103/PhysRevD.60.034002
SU-4240-693
hep-ph
null
We study the eta' to eta pi pi decay within an effective chiral Lagrangian approach in which the lowest lying scalar meson candidates sigma(560) and kappa(900) together with the f0(980) and a0(980) are combined into a possible nonet. We show that there exists a unique choice of the free parameters of this model which, in addition to fitting the pi pi and pi K scattering amplitudes, well describes the experimental measurements for the partial decay width of eta' to eta pi pi and the energy dependence of this decay. As a by-product, we estimate the a0(980) width to be 70 MeV, in agreement with a new experimental analysis.
[ { "created": "Wed, 3 Feb 1999 21:13:47 GMT", "version": "v1" } ]
2009-10-31
[ [ "Fariborz", "Amir H.", "" ], [ "Schechter", "Joseph", "" ] ]
We study the eta' to eta pi pi decay within an effective chiral Lagrangian approach in which the lowest lying scalar meson candidates sigma(560) and kappa(900) together with the f0(980) and a0(980) are combined into a possible nonet. We show that there exists a unique choice of the free parameters of this model which, in addition to fitting the pi pi and pi K scattering amplitudes, well describes the experimental measurements for the partial decay width of eta' to eta pi pi and the energy dependence of this decay. As a by-product, we estimate the a0(980) width to be 70 MeV, in agreement with a new experimental analysis.
1612.08933
Andreas Ringwald
Andreas Ringwald
Alternative dark matter candidates: Axions
6 pages, 2 figures, contribution to the proceedings of the Neutrino Oscillation Workshop 2016, 4 - 11 September, 2016, Otranto, Lecce, Italy
null
null
DESY 16-236
hep-ph astro-ph.CO hep-ex
http://creativecommons.org/licenses/by/4.0/
The axion is arguably one of the best motivated candidates for dark matter. For a decay constant greater than about 10^9 GeV, axions are dominantly produced non-thermally in the early universe and hence are "cold", their velocity dispersion being small enough to fit to large scale structure. Moreover, such a large decay constant ensures the stability at cosmological time scales and its behaviour as a collisionless fluid at cosmological length scales. Here, we review the state of the art of axion dark matter predictions and of experimental efforts to search for axion dark matter in laboratory experiments.
[ { "created": "Wed, 28 Dec 2016 17:24:13 GMT", "version": "v1" } ]
2016-12-30
[ [ "Ringwald", "Andreas", "" ] ]
The axion is arguably one of the best motivated candidates for dark matter. For a decay constant greater than about 10^9 GeV, axions are dominantly produced non-thermally in the early universe and hence are "cold", their velocity dispersion being small enough to fit to large scale structure. Moreover, such a large decay constant ensures the stability at cosmological time scales and its behaviour as a collisionless fluid at cosmological length scales. Here, we review the state of the art of axion dark matter predictions and of experimental efforts to search for axion dark matter in laboratory experiments.
hep-ph/9509266
Tsuneo Suzuki
Tsuneo Suzuki
Quark Confinement in QCD and New Bosons
20 Pages, REVTeX; Incorrect expressions are revised and some new descriptions are added
null
null
Kanazawa 95-11
hep-ph hep-lat hep-th
null
If the dual Meissner effect due to abelian monopole condensation is the quark confinement mechanism of QCD as suggested in recent Monte-Carlo simulations of lattice QCD, new axial-vector and scalar bosons with the mass of O(1GeV) would appear as physical states which are different from ordinary hadrons and glueballs. The axial-vector boson can not decay into ordinary color-singlet hadrons and glueballs owing to a remainig global discrete permutation symmetry with respect to colors (Weyl symmetry) if the vacuum respects the symmetry as suggested from lattice MC simulations.
[ { "created": "Mon, 11 Sep 1995 12:22:52 GMT", "version": "v1" }, { "created": "Sat, 4 Nov 1995 04:52:07 GMT", "version": "v2" } ]
2008-02-03
[ [ "Suzuki", "Tsuneo", "" ] ]
If the dual Meissner effect due to abelian monopole condensation is the quark confinement mechanism of QCD as suggested in recent Monte-Carlo simulations of lattice QCD, new axial-vector and scalar bosons with the mass of O(1GeV) would appear as physical states which are different from ordinary hadrons and glueballs. The axial-vector boson can not decay into ordinary color-singlet hadrons and glueballs owing to a remainig global discrete permutation symmetry with respect to colors (Weyl symmetry) if the vacuum respects the symmetry as suggested from lattice MC simulations.
2205.05042
Ferenc Gl\"uck
Ferenc Gl\"uck
Radiative corrections to neutron and nuclear $\beta$-decays: a serious kinematics problem in the literature
32 pages, 9 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We report a serious kinematics problem in the bremsstrahlung photon part of the order-$\alpha$ outer (model independent) radiative correction calculations for those neutron (and nuclear beta) decay observables (like electron-neutrino correlation parameter measurement) where the proton (recoil particle) is detected. The so-called neutrino-type radiative correction calculations, which fix the neutrino direction in the bremsstrahlung photon integrals, use 3-body decay kinematics to connect the unobserved neutrino direction with the observed electron and proton (recoil particle) momenta. But the presence of the bremsstrahlung photon changes the kinematics from 3-body to 4-body one, and the accurate information about the recoil particle momentum is lost due to the integration with respect to the photon momentum. Therefore the application of the abovementioned 3-body decay kinematics connection for the radiative correction calculations, rather prevalent in the literature, is not acceptable. We show that the correct, so-called recoil-type radiative correction calculations, which fix the proton (recoil particle) momentum instead of the neutrino direction and use rather involved analytical, semianalytical or Monte Carlo bremsstrahlung integration methods, result usually in much larger corrections than the incorrect neutrino-type analytical methods.
[ { "created": "Tue, 10 May 2022 16:56:21 GMT", "version": "v1" }, { "created": "Wed, 16 Nov 2022 18:38:57 GMT", "version": "v2" } ]
2022-11-17
[ [ "Glück", "Ferenc", "" ] ]
We report a serious kinematics problem in the bremsstrahlung photon part of the order-$\alpha$ outer (model independent) radiative correction calculations for those neutron (and nuclear beta) decay observables (like electron-neutrino correlation parameter measurement) where the proton (recoil particle) is detected. The so-called neutrino-type radiative correction calculations, which fix the neutrino direction in the bremsstrahlung photon integrals, use 3-body decay kinematics to connect the unobserved neutrino direction with the observed electron and proton (recoil particle) momenta. But the presence of the bremsstrahlung photon changes the kinematics from 3-body to 4-body one, and the accurate information about the recoil particle momentum is lost due to the integration with respect to the photon momentum. Therefore the application of the abovementioned 3-body decay kinematics connection for the radiative correction calculations, rather prevalent in the literature, is not acceptable. We show that the correct, so-called recoil-type radiative correction calculations, which fix the proton (recoil particle) momentum instead of the neutrino direction and use rather involved analytical, semianalytical or Monte Carlo bremsstrahlung integration methods, result usually in much larger corrections than the incorrect neutrino-type analytical methods.
hep-ph/9508358
George Sterman
George Sterman
Soft Gluon Resummation
15 Pages, 5 Postscript figures, uses epsf.sty (corrected figures)
AIP Conf.Proc.357:608-622,1996
10.1063/1.49628
ITP-SB-95-30
hep-ph
null
I discuss some of the basic techniques and results of soft gluon resummation, and their applications to scattering at collider energies.
[ { "created": "Wed, 23 Aug 1995 19:16:06 GMT", "version": "v1" }, { "created": "Thu, 24 Aug 1995 19:17:45 GMT", "version": "v2" } ]
2014-11-17
[ [ "Sterman", "George", "" ] ]
I discuss some of the basic techniques and results of soft gluon resummation, and their applications to scattering at collider energies.
0805.3623
Egle Tomasi-Gustafsson
E. A. Kuraev, Yu. Bystritskiy, S. Bakmaev, V.V. Bytev, E. Tomasi-Gustafsson
High order radiative corrections for unpolarized electron proton elastic scattering at low $Q^2$
11 pages, 3 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the effect of high order radiative corrections in unpolarized electron proton elastic scattering and compare with the calculations at lowest order, which are usually applied to experimental data. We show that higher order terms play a role, starting from values of the momentum transfer squared, $Q^2$, larger than the electron mass. Particular attention is devoted to the $\epsilon$ dependence of radiative corrections.
[ { "created": "Fri, 23 May 2008 12:37:10 GMT", "version": "v1" } ]
2008-05-26
[ [ "Kuraev", "E. A.", "" ], [ "Bystritskiy", "Yu.", "" ], [ "Bakmaev", "S.", "" ], [ "Bytev", "V. V.", "" ], [ "Tomasi-Gustafsson", "E.", "" ] ]
We investigate the effect of high order radiative corrections in unpolarized electron proton elastic scattering and compare with the calculations at lowest order, which are usually applied to experimental data. We show that higher order terms play a role, starting from values of the momentum transfer squared, $Q^2$, larger than the electron mass. Particular attention is devoted to the $\epsilon$ dependence of radiative corrections.
2208.08432
Tisa Biswas
Tisa Biswas, Anindya Datta
Exploring Higgs-Photon Production at the LHC
38 pages, 19 figures and 11 tables; version accepted for publication in JHEP
J. High Energ. Phys. 2023, 104 (2023)
10.1007/JHEP05(2023)104
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We have investigated the signal for physics beyond the Standard Model via Higgs plus photon final state, hitherto unobserved at the LHC, in the framework of Standard Model Effective Field Theory. Using the relevant dimension-6 operators, we probe two distinct classes of interactions, based on the Lorentz structure of Higgs couplings to gauge bosons and fermions. To begin with, constraints on the Wilson coefficients of these operators have been derived from existing experimental data. We then focus on the hadronic decay of the Higgs boson to two bottom quarks in the boosted regime, leading to a high $p_T$ fat-jet recoiling against a hard photon. Following a CMS Run II search for a resonance decaying into a Higgs boson and a photon, a detailed signal and background analysis for this channel has been done and limits on the relevant Wilson coefficients have been obtained. By performing a cut-based analysis, we identify some kinematic observables that distinguish between signal and SM background. Minimum values of the Wilson coefficients that will yield $3\sigma$ signal significance at the 14 TeV run of the LHC with $3000 ~\rm fb^{-1}$ data, have been obtained. A multivariate analysis using a boosted decision tree and exploiting the jet substructure techniques further help to isolate the regions of phase space where the contribution of SMEFT driven signal is significantly enhanced. Finally, we briefly discuss the parameter dependencies and interpretations of the allowed values of the coefficients on a particularly interesting UV complete model namely, Minimal Supersymmetric Standard Model.
[ { "created": "Wed, 17 Aug 2022 17:51:30 GMT", "version": "v1" }, { "created": "Sat, 6 May 2023 10:16:27 GMT", "version": "v2" } ]
2023-05-17
[ [ "Biswas", "Tisa", "" ], [ "Datta", "Anindya", "" ] ]
We have investigated the signal for physics beyond the Standard Model via Higgs plus photon final state, hitherto unobserved at the LHC, in the framework of Standard Model Effective Field Theory. Using the relevant dimension-6 operators, we probe two distinct classes of interactions, based on the Lorentz structure of Higgs couplings to gauge bosons and fermions. To begin with, constraints on the Wilson coefficients of these operators have been derived from existing experimental data. We then focus on the hadronic decay of the Higgs boson to two bottom quarks in the boosted regime, leading to a high $p_T$ fat-jet recoiling against a hard photon. Following a CMS Run II search for a resonance decaying into a Higgs boson and a photon, a detailed signal and background analysis for this channel has been done and limits on the relevant Wilson coefficients have been obtained. By performing a cut-based analysis, we identify some kinematic observables that distinguish between signal and SM background. Minimum values of the Wilson coefficients that will yield $3\sigma$ signal significance at the 14 TeV run of the LHC with $3000 ~\rm fb^{-1}$ data, have been obtained. A multivariate analysis using a boosted decision tree and exploiting the jet substructure techniques further help to isolate the regions of phase space where the contribution of SMEFT driven signal is significantly enhanced. Finally, we briefly discuss the parameter dependencies and interpretations of the allowed values of the coefficients on a particularly interesting UV complete model namely, Minimal Supersymmetric Standard Model.
2303.16400
Yong Du
Yong Du
Type-II seesaw Complex Triplet Model: Phase Transition and A Global Fit Analysis
8 pages with refs, 5 figures, 1 table; proceeding for Higgs Potential 2022; extended discussion on global fit of the type-II seesaw model and {\mu} to e{\gamma} with 2 new figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The type-II seesaw model can explain neutrino masses and address the baryon asymmetry problem of the Universe simultaneously. In this letter, we explore its phase transition and the resulting gravitational wave signals. We find a strong first-order electroweak phase transition generically prefers a relatively light triplet in the $300\sim500$GeV range, which is ideal for collider searches and can generate gravitational waves within the sensitivity reach of BBO and Ultimate-DECIGO. While above $\sim$1TeV where a future 100TeV $pp$ collider will play a key role in model discovery, we integrate out the triplet and perform a global fit analysis of this model at various future colliders. A lower bound in the $10^{-3}\sim10^{-2}$eV range on the triplet vacuum expectation value is obtained, which is comparable to or even better than that from current $\mu\to e\gamma$ experiments depending on the lightest neutrino mass.
[ { "created": "Wed, 29 Mar 2023 02:22:32 GMT", "version": "v1" } ]
2023-03-30
[ [ "Du", "Yong", "" ] ]
The type-II seesaw model can explain neutrino masses and address the baryon asymmetry problem of the Universe simultaneously. In this letter, we explore its phase transition and the resulting gravitational wave signals. We find a strong first-order electroweak phase transition generically prefers a relatively light triplet in the $300\sim500$GeV range, which is ideal for collider searches and can generate gravitational waves within the sensitivity reach of BBO and Ultimate-DECIGO. While above $\sim$1TeV where a future 100TeV $pp$ collider will play a key role in model discovery, we integrate out the triplet and perform a global fit analysis of this model at various future colliders. A lower bound in the $10^{-3}\sim10^{-2}$eV range on the triplet vacuum expectation value is obtained, which is comparable to or even better than that from current $\mu\to e\gamma$ experiments depending on the lightest neutrino mass.
1208.5457
Roberto Pittau
Roberto Pittau
A four-dimensional approach to quantum field theories
25 pages, 12 figures. A few misprints corrected. Accepted by JHEP
JHEP11(2012)151
10.1007/JHEP11(2012)151
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I present a novel Four-Dimensional Regularization/Renormalization approach (FDR) to ultraviolet divergences in field theories which can be interpreted as a natural separation between physical and non physical degrees of freedom. Based on the observation that some infinities can be reabsorbed into the vacuum expectation value of the fields, rather than into the parameters of the Lagrangian, a new type of four-dimensional loop integral is introduced (the FDR integral) which is independent of any UV regulator and respects all properties required by gauge invariance. FDR reproduces the correct ABJ anomaly and no change in the definition of gamma_5 is needed. With FDR the possibility is open for an approach to UV infinities in which the renormalization program is substituted by a simple reinterpretation of the appearing loop integrals as FDR ones, leading to important consequences in the context of non-renormalizable field theories. Finally, I show how FDR can also be used to regularize infrared and collinear divergences.
[ { "created": "Mon, 27 Aug 2012 17:51:20 GMT", "version": "v1" }, { "created": "Thu, 22 Nov 2012 14:45:22 GMT", "version": "v2" } ]
2012-12-03
[ [ "Pittau", "Roberto", "" ] ]
I present a novel Four-Dimensional Regularization/Renormalization approach (FDR) to ultraviolet divergences in field theories which can be interpreted as a natural separation between physical and non physical degrees of freedom. Based on the observation that some infinities can be reabsorbed into the vacuum expectation value of the fields, rather than into the parameters of the Lagrangian, a new type of four-dimensional loop integral is introduced (the FDR integral) which is independent of any UV regulator and respects all properties required by gauge invariance. FDR reproduces the correct ABJ anomaly and no change in the definition of gamma_5 is needed. With FDR the possibility is open for an approach to UV infinities in which the renormalization program is substituted by a simple reinterpretation of the appearing loop integrals as FDR ones, leading to important consequences in the context of non-renormalizable field theories. Finally, I show how FDR can also be used to regularize infrared and collinear divergences.
1608.04559
Karim Ghorbani
Karim Ghorbani and Leila Khalkhali
Mono-Higgs signature in fermionic dark matter model
23 pages, clarifications added, journal version
J.Phys. G44 (2017) 105004
10.1088/1361-6471/aa823a
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In light of the Higgs boson discovery, we explore mono-Higgs signature in association with dark matter pair production at the LHC in a renormalizable model with a fermionic dark matter candidate. For two channels with $\gamma\gamma+\text{MET}$ and $b \bar b+\text{MET}$ in the final state we simulate the SM backgrounds and signal events at $\sqrt{s} = 14$ TeV. We then estimate the LHC sensitivities for various benchmark points for two integrated luminosities ${\cal L} = 300~\text{fb}^{-1}$ and ${\cal L} = 3~ \text{ab}^{-1}$. We constrain the Yukawa coupling of the dark matter-SM interaction, taking into account bounds from mono-Higgs signature, observed dark matter relic density, Higgs physics, perturbativity requirement and electroweak measurements. Concerning the mono-Higgs search, it turns out that the channel with the largest branching ratio, $b \bar b$ channel, provides better sensitivity. There are found regions in the parameter space of the model compatible with all the bounds mentioned above which can be reached in future LHC studies.
[ { "created": "Tue, 16 Aug 2016 11:51:51 GMT", "version": "v1" }, { "created": "Tue, 17 Jan 2017 08:43:00 GMT", "version": "v2" }, { "created": "Sat, 12 Aug 2017 17:59:33 GMT", "version": "v3" } ]
2017-09-06
[ [ "Ghorbani", "Karim", "" ], [ "Khalkhali", "Leila", "" ] ]
In light of the Higgs boson discovery, we explore mono-Higgs signature in association with dark matter pair production at the LHC in a renormalizable model with a fermionic dark matter candidate. For two channels with $\gamma\gamma+\text{MET}$ and $b \bar b+\text{MET}$ in the final state we simulate the SM backgrounds and signal events at $\sqrt{s} = 14$ TeV. We then estimate the LHC sensitivities for various benchmark points for two integrated luminosities ${\cal L} = 300~\text{fb}^{-1}$ and ${\cal L} = 3~ \text{ab}^{-1}$. We constrain the Yukawa coupling of the dark matter-SM interaction, taking into account bounds from mono-Higgs signature, observed dark matter relic density, Higgs physics, perturbativity requirement and electroweak measurements. Concerning the mono-Higgs search, it turns out that the channel with the largest branching ratio, $b \bar b$ channel, provides better sensitivity. There are found regions in the parameter space of the model compatible with all the bounds mentioned above which can be reached in future LHC studies.
1812.01001
Stephan Narison
R. Albuquerque (FAT, UERJ, Rio de Janeiro-BR), S. Narison (LUPM, CNRS-IN2P3, Montpellier-FR), A. Rabemananjara, D. Rabetiarivony, G. Randriamanatrika (IHEPMAD, Antananarivo-MG)
XYZ -- spectra from QCD Laplace Sum Rules at Higher Orders
Talk given at QCD18 (2-8 july 2018, Montpellier-FR) and at HEPMAD18 (6-11 september 2018, Antananarivo-MG) 10 pages, 7 figures, 11 tables.Reference corrected. arXiv admin note: substantial text overlap with arXiv:1801.03073, arXiv:1709.09023, arXiv:1612.03438, arXiv:1609.03351
null
null
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We review our results in Refs.[1,2] for the masses and couplings of heavy-light DD(BB)-like molecules and (Qq)(Qq)-like four-quark states from relativistic QCD Laplace sum rules (LSR) where next-to-next-to-leading order (N2LO) PT corrections in the chiral limit, next-to-leading order (NLO) SU3 PT corrections and non-perturbative contributions up to dimension d=6-8 are included. The factorization properties of molecule and four-quark currents have been used for the estimate of the higher order PT corrections. New integrated compact expressions of the spectral functions at leading order (LO) of perturbative QCD and up to dimensions d< (6 - 8) non-perturbative condensates are presented. The results are summarized in Tables 5 to 10, from which we conclude, within the errors, that the observed XZ states are good candidates for being 1^{++} and 0^{++} molecules or/and four-quark states, contrary to the observed Y states which are too light compared to the predicted 1^{-\pm} and 0^{-\pm} states. We find that the SU3 breakings are relatively small for the masses (< 10(resp. 3)%) for the charm (resp. bottom) channels while they are large (< 20%) for the couplings which decrease faster (1/m_{b}^{3/2}) than 1/m_{b}^{1/2} of HQET. QCD spectral sum rules (QSSR) approach cannot clearly separate (within the errors) molecules from four-quark states having the same quantum numbers. Results for the BK (DK)-like molecules and (Qq)(us)-like four-quark states from [3] are also reviewed which do not favour the molecule or/and four-quark interpretation of the X(5568). We suggest to scan the charm (2327 ~ 2444) MeV and bottom (5173 ~ 5226) MeV regions for detecting the (unmixed)(cu)ds and (bu)ds states. We expect that future experimental data and lattice results will check our predictions.
[ { "created": "Mon, 3 Dec 2018 15:20:27 GMT", "version": "v1" }, { "created": "Mon, 7 Aug 2023 07:57:21 GMT", "version": "v2" } ]
2023-08-09
[ [ "Albuquerque", "R.", "", "FAT, UERJ, Rio de Janeiro-BR" ], [ "Narison", "S.", "", "LUPM,\n CNRS-IN2P3, Montpellier-FR" ], [ "Rabemananjara", "A.", "", "IHEPMAD, Antananarivo-MG" ], [ "Rabetiarivony", "D.", "", "IHEPMAD, Antananarivo-MG" ...
We review our results in Refs.[1,2] for the masses and couplings of heavy-light DD(BB)-like molecules and (Qq)(Qq)-like four-quark states from relativistic QCD Laplace sum rules (LSR) where next-to-next-to-leading order (N2LO) PT corrections in the chiral limit, next-to-leading order (NLO) SU3 PT corrections and non-perturbative contributions up to dimension d=6-8 are included. The factorization properties of molecule and four-quark currents have been used for the estimate of the higher order PT corrections. New integrated compact expressions of the spectral functions at leading order (LO) of perturbative QCD and up to dimensions d< (6 - 8) non-perturbative condensates are presented. The results are summarized in Tables 5 to 10, from which we conclude, within the errors, that the observed XZ states are good candidates for being 1^{++} and 0^{++} molecules or/and four-quark states, contrary to the observed Y states which are too light compared to the predicted 1^{-\pm} and 0^{-\pm} states. We find that the SU3 breakings are relatively small for the masses (< 10(resp. 3)%) for the charm (resp. bottom) channels while they are large (< 20%) for the couplings which decrease faster (1/m_{b}^{3/2}) than 1/m_{b}^{1/2} of HQET. QCD spectral sum rules (QSSR) approach cannot clearly separate (within the errors) molecules from four-quark states having the same quantum numbers. Results for the BK (DK)-like molecules and (Qq)(us)-like four-quark states from [3] are also reviewed which do not favour the molecule or/and four-quark interpretation of the X(5568). We suggest to scan the charm (2327 ~ 2444) MeV and bottom (5173 ~ 5226) MeV regions for detecting the (unmixed)(cu)ds and (bu)ds states. We expect that future experimental data and lattice results will check our predictions.
1504.07640
P. S. Bhupal Dev
P.S. Bhupal Dev, Peter Millington, Apostolos Pilaftsis, Daniele Teresi
Corrigendum to "Flavour Covariant Transport Equations: an Application to Resonant Leptogenesis"
10 pages, 4 figures; journal version
Nucl. Phys. B 897 (2015) 749
10.1016/j.nuclphysb.2015.06.015
MAN/HEP/2015/06, TUM/HEP/994/15
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We amend the incorrect discussion in Nucl. Phys. B 886 (2014) 569 [1] concerning the numerical examples considered there. In particular, we discuss the viability of minimal radiative models of Resonant Leptogenesis and prove that no asymmetry can be generated at $\mathcal{O}(h^4)$ in these scenarios. We present a minimal modification of the model considered in [1], where electroweak-scale right-handed Majorana neutrinos can easily accommodate both successful leptogenesis and observable signatures at Lepton Number and Flavour Violation experiments. The importance of the fully flavour-covariant rate equations, as developed in [1], for describing accurately the generation of the lepton asymmetry is reconfirmed.
[ { "created": "Mon, 27 Apr 2015 09:48:39 GMT", "version": "v1" }, { "created": "Wed, 24 Jun 2015 08:49:20 GMT", "version": "v2" } ]
2015-06-25
[ [ "Dev", "P. S. Bhupal", "" ], [ "Millington", "Peter", "" ], [ "Pilaftsis", "Apostolos", "" ], [ "Teresi", "Daniele", "" ] ]
We amend the incorrect discussion in Nucl. Phys. B 886 (2014) 569 [1] concerning the numerical examples considered there. In particular, we discuss the viability of minimal radiative models of Resonant Leptogenesis and prove that no asymmetry can be generated at $\mathcal{O}(h^4)$ in these scenarios. We present a minimal modification of the model considered in [1], where electroweak-scale right-handed Majorana neutrinos can easily accommodate both successful leptogenesis and observable signatures at Lepton Number and Flavour Violation experiments. The importance of the fully flavour-covariant rate equations, as developed in [1], for describing accurately the generation of the lepton asymmetry is reconfirmed.
2002.10871
Eugenio Megias
E. Megias, E. Ruiz Arriola, L.L. Salcedo
Quark-diquark string tension, excited baryonic resonances and thermal fluctuations
17 pages, 7 figures, 1 table; v2 typos corrected, added references, introduction and Sec. 4.3 extended. arXiv admin note: text overlap with arXiv:1812.09365
null
10.1088/1402-4896/ab8d01
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the baryonic fluctuations from second to eighth order involving electric charge, baryon number and strangeness below the quark-gluon plasma crossover and numerically known from lattice QCD calculations. By considering a particular realization of the Hadron Resonance Gas model, we provide evidence on the dominant role of quark-diquark degrees of freedom to describe excited baryonic resonances. After proving by means of suitable Polyakov loop correlators that the quark-diquark and the quark-antiquark forces coincide, $V_{\bar q q } (r) = V_{\bar q D } (r) + \textrm{const}$, we find that the corresponding susceptibilities can be saturated with excited baryonic states in a quark-diquark model picture.
[ { "created": "Mon, 24 Feb 2020 18:35:32 GMT", "version": "v1" }, { "created": "Thu, 14 May 2020 14:08:58 GMT", "version": "v2" } ]
2020-06-24
[ [ "Megias", "E.", "" ], [ "Arriola", "E. Ruiz", "" ], [ "Salcedo", "L. L.", "" ] ]
We study the baryonic fluctuations from second to eighth order involving electric charge, baryon number and strangeness below the quark-gluon plasma crossover and numerically known from lattice QCD calculations. By considering a particular realization of the Hadron Resonance Gas model, we provide evidence on the dominant role of quark-diquark degrees of freedom to describe excited baryonic resonances. After proving by means of suitable Polyakov loop correlators that the quark-diquark and the quark-antiquark forces coincide, $V_{\bar q q } (r) = V_{\bar q D } (r) + \textrm{const}$, we find that the corresponding susceptibilities can be saturated with excited baryonic states in a quark-diquark model picture.
1205.5890
Ilya F. Ginzburg
I. F. Ginzburg
Light charged Higgs at LHC
2 pages,2 figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The LHC program for discovery of light charged Higgs with mass 135-180 GeV has to take into account decay $H^+\to \bar{b}\,t^*\to W^+b\bar{b}$. The distribution of decay products in effective mass of $t^*=Wb$ is obtained.
[ { "created": "Sat, 26 May 2012 15:54:39 GMT", "version": "v1" }, { "created": "Tue, 13 Nov 2012 10:22:53 GMT", "version": "v2" } ]
2012-11-14
[ [ "Ginzburg", "I. F.", "" ] ]
The LHC program for discovery of light charged Higgs with mass 135-180 GeV has to take into account decay $H^+\to \bar{b}\,t^*\to W^+b\bar{b}$. The distribution of decay products in effective mass of $t^*=Wb$ is obtained.
hep-ph/9911205
Sergey Goloskokov
S.V.Goloskokov
Spin Effects in Diffractive $Q \bar Q$ Production and Compass Experiment
8 pages, latex, 5 figures, talk at the Iternational Workshop "Symmetry and Spin", Prague-Spin99, Prague, September 5 - 12, 1999. To be published in proceedings
Czech.J.Phys. 50S1 (2000) 145-152
null
null
hep-ph
null
We calculate the double spin asymmetry of the diffractive $Q \bar Q$ and vector meson leptoproduction at COMPASS energies. We analyze dependences of the asymmetry on the structure of the Pomeron-proton coupling. It is shown that it is difficult to study the spin structure of the Pomeron coupling with the proton from the A_{ll} asymmetry. The A_{lT} asymmetry might be an appropriate object for this investigation.
[ { "created": "Tue, 2 Nov 1999 11:28:19 GMT", "version": "v1" } ]
2007-05-23
[ [ "Goloskokov", "S. V.", "" ] ]
We calculate the double spin asymmetry of the diffractive $Q \bar Q$ and vector meson leptoproduction at COMPASS energies. We analyze dependences of the asymmetry on the structure of the Pomeron-proton coupling. It is shown that it is difficult to study the spin structure of the Pomeron coupling with the proton from the A_{ll} asymmetry. The A_{lT} asymmetry might be an appropriate object for this investigation.
hep-ph/0006203
Jungil Lee
Jungil Lee (Hamburg)
Current Issues In Quarkonium Production
6 pages, 2 figures, Talk presented at the DIS 2000, Liverpool, England, April 25-30, 2000
null
null
null
hep-ph
null
As a stringent test of the nonrelativistic QCD factorization approach for inclusive heavy-quarkonium production in high-energy hadron collision, the polarized heavy-quarkonium production at the Tevatron is discussed. The polarization of prompt J/psi at the Tevatron is predicted within the nonrelativistic QCD factorization framework. The contribution from radiative decays of P-wave charmonium states decreases, but does not eliminate, the transverse polarization at large transverse momentum. The prediction agrees with measurements from the CDF collaboration at intermediate values of p_T, but disagrees at the large values of p_T measured. Recent preliminary data of heavy quarkonia from CDF and theoretical/experimental prospects related to the Run II heavy quarkonium physics are also discussed.
[ { "created": "Sat, 17 Jun 2000 11:48:27 GMT", "version": "v1" } ]
2007-05-23
[ [ "Lee", "Jungil", "", "Hamburg" ] ]
As a stringent test of the nonrelativistic QCD factorization approach for inclusive heavy-quarkonium production in high-energy hadron collision, the polarized heavy-quarkonium production at the Tevatron is discussed. The polarization of prompt J/psi at the Tevatron is predicted within the nonrelativistic QCD factorization framework. The contribution from radiative decays of P-wave charmonium states decreases, but does not eliminate, the transverse polarization at large transverse momentum. The prediction agrees with measurements from the CDF collaboration at intermediate values of p_T, but disagrees at the large values of p_T measured. Recent preliminary data of heavy quarkonia from CDF and theoretical/experimental prospects related to the Run II heavy quarkonium physics are also discussed.
1912.11015
Greger Torgrimsson
Victor Dinu and Greger Torgrimsson
Approximating higher-order nonlinear QED processes with first-order building blocks
Version 2: numerical results added before journal submission, previous results unchanged. 19 pages, 8 figures
Phys. Rev. D 102, 016018 (2020)
10.1103/PhysRevD.102.016018
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Higher-order tree-level processes in strong laser fields, i.e. cascades, are in general extremely difficult to calculate, but in some regimes the dominant contribution comes from a sequence of first-order processes, i.e. nonlinear Compton scattering and nonlinear Breit-Wheeler pair production. At high intensity the field can be treated as locally constant, which is the basis for standard particle-in-cell codes. However, the locally-constant-field (LCF) approximation and these particle-in-cell codes cannot be used when the intensity is only moderately high, which is a regime that is experimentally relevant. We have shown that one can still use a sequence of first-order processes to estimate higher orders at moderate intensities provided the field is sufficiently long. An important aspect of our new "gluing" approach is the role of the spin/polarization of intermediate particles, which is more nontrivial compared to the LCF regime.
[ { "created": "Mon, 23 Dec 2019 18:16:23 GMT", "version": "v1" }, { "created": "Thu, 4 Jun 2020 14:19:15 GMT", "version": "v2" } ]
2020-08-05
[ [ "Dinu", "Victor", "" ], [ "Torgrimsson", "Greger", "" ] ]
Higher-order tree-level processes in strong laser fields, i.e. cascades, are in general extremely difficult to calculate, but in some regimes the dominant contribution comes from a sequence of first-order processes, i.e. nonlinear Compton scattering and nonlinear Breit-Wheeler pair production. At high intensity the field can be treated as locally constant, which is the basis for standard particle-in-cell codes. However, the locally-constant-field (LCF) approximation and these particle-in-cell codes cannot be used when the intensity is only moderately high, which is a regime that is experimentally relevant. We have shown that one can still use a sequence of first-order processes to estimate higher orders at moderate intensities provided the field is sufficiently long. An important aspect of our new "gluing" approach is the role of the spin/polarization of intermediate particles, which is more nontrivial compared to the LCF regime.
2303.15524
Thomas Schwetz
Raphael Krueger, Thomas Schwetz
Decoherence effects in reactor and Gallium neutrino oscillation experiments -- a QFT approach
20 pages + 3 appendices and references
null
10.1140/epjc/s10052-023-11711-8
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We adopt the quantum field theoretical method to calculate the amplitude and event rate for a neutrino oscillation experiment, considering neutrino production, propagation and detection as a single process. This method allows to take into account decoherence effects in the transition amplitude induced by the quantum mechanical uncertainties of all particles involved in the process. We extend the method to include coherence loss due to interactions with the environment, similar to collisional line broadening. In addition to generic decoherence induced at the amplitude level, the formalism allows to include, in a straightforward way, additional damping effects related to phase-space integrals over momenta of unobserved particles as well as other classical averaging effects. We apply this method to neutrino oscillation searches at reactor and Gallium experiments and confirm that quantum decoherence is many orders of magnitudes smaller than classical averaging effects and therefore unobservable. The method used here can be applied with minimal modifications also to other types of oscillation experiments, e.g., accelerator based beam experiments.
[ { "created": "Mon, 27 Mar 2023 18:08:01 GMT", "version": "v1" } ]
2023-07-26
[ [ "Krueger", "Raphael", "" ], [ "Schwetz", "Thomas", "" ] ]
We adopt the quantum field theoretical method to calculate the amplitude and event rate for a neutrino oscillation experiment, considering neutrino production, propagation and detection as a single process. This method allows to take into account decoherence effects in the transition amplitude induced by the quantum mechanical uncertainties of all particles involved in the process. We extend the method to include coherence loss due to interactions with the environment, similar to collisional line broadening. In addition to generic decoherence induced at the amplitude level, the formalism allows to include, in a straightforward way, additional damping effects related to phase-space integrals over momenta of unobserved particles as well as other classical averaging effects. We apply this method to neutrino oscillation searches at reactor and Gallium experiments and confirm that quantum decoherence is many orders of magnitudes smaller than classical averaging effects and therefore unobservable. The method used here can be applied with minimal modifications also to other types of oscillation experiments, e.g., accelerator based beam experiments.
2205.12455
Liliana Vazquez
S. Rebeca Ju\'arez Wysozka, Piotr Kielanowski, Liliana Vazquez Mercado
Quark unitarity triangles
null
null
10.1142/S0217751X22501639
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The angles of all unitarity triangles of the Cabibbo-Kobayashi-Maskawa matrix are determined from the experimental data. Our analysis is independent of the parameterization of the CKM matrix and it is based on the predictions of the unitarity for the angles and the areas of the unitarity triangles. We note that the lengths of the sides of the four unitarity triangles determined from the experimental data do not form a triangle. We resolve this incompatibility by performing a constrained fit, assuming the equality of the area of the unitarity triangles. We demonstrate that the measured data are compatible with the predictions of the unitarity of the Cabibbo-Kobayashi-Maskawa matrix, but there is a $2\sigma$ tension for one of the triangles. We show that the angles of the unitarity triangles obtained by the multiplication of the rows of the CKM matrix can be obtained from the angles obtained by the multiplication of the columns. The equality of those two types of the angles is a simple, but a very powerful test of the general structure of the Standard Model.
[ { "created": "Wed, 25 May 2022 02:57:19 GMT", "version": "v1" } ]
2022-12-07
[ [ "Wysozka", "S. Rebeca Juárez", "" ], [ "Kielanowski", "Piotr", "" ], [ "Mercado", "Liliana Vazquez", "" ] ]
The angles of all unitarity triangles of the Cabibbo-Kobayashi-Maskawa matrix are determined from the experimental data. Our analysis is independent of the parameterization of the CKM matrix and it is based on the predictions of the unitarity for the angles and the areas of the unitarity triangles. We note that the lengths of the sides of the four unitarity triangles determined from the experimental data do not form a triangle. We resolve this incompatibility by performing a constrained fit, assuming the equality of the area of the unitarity triangles. We demonstrate that the measured data are compatible with the predictions of the unitarity of the Cabibbo-Kobayashi-Maskawa matrix, but there is a $2\sigma$ tension for one of the triangles. We show that the angles of the unitarity triangles obtained by the multiplication of the rows of the CKM matrix can be obtained from the angles obtained by the multiplication of the columns. The equality of those two types of the angles is a simple, but a very powerful test of the general structure of the Standard Model.
1103.1749
Sangho Kim
Sang-Ho Kim, Seung-il Nam, Yongseok Oh, and Hyun-Chul Kim
K*{\Lambda}(1116) photoproduction and nucleon resonances
2 pages, 2 figures, talk given at International Conference on the structure of baryons, BARYONS'10, Dec. 7-11, 2010, Osaka, Japan
null
10.1063/1.3647388
INHA-NTG-03/2011
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this presentation, we report our recent studies on the $K^*\Lambda(1116)$ photoproduction off the proton target, using the tree-level Born approximation, via the effective Lagrangian approach. In addition, we include the nine (three- or four-star confirmed) nucleon resonances below the threshold $\sqrt{s}_\mathrm{th}\approx2008$ MeV, to interpret the discrepancy between the experiment and previous theoretical studies, in the vicinity of the threshold region. From the numerical studies, we observe that the $S_{11}(1535)$ and $S_{11}(1650)$ play an important role for the cross-section enhancement near the $\sqrt{s}_\mathrm{th}$. It also turns out that, in order to reproduce the data, we have the vector coupling constants $g_{K^*S_{11}(1535)\Lambda}=(7.0\sim9.0)$ and $g_{K^*S_{11}(1650)\Lambda}=(5.0\sim6.0)$.
[ { "created": "Wed, 9 Mar 2011 10:13:02 GMT", "version": "v1" } ]
2015-05-27
[ [ "Kim", "Sang-Ho", "" ], [ "Nam", "Seung-il", "" ], [ "Oh", "Yongseok", "" ], [ "Kim", "Hyun-Chul", "" ] ]
In this presentation, we report our recent studies on the $K^*\Lambda(1116)$ photoproduction off the proton target, using the tree-level Born approximation, via the effective Lagrangian approach. In addition, we include the nine (three- or four-star confirmed) nucleon resonances below the threshold $\sqrt{s}_\mathrm{th}\approx2008$ MeV, to interpret the discrepancy between the experiment and previous theoretical studies, in the vicinity of the threshold region. From the numerical studies, we observe that the $S_{11}(1535)$ and $S_{11}(1650)$ play an important role for the cross-section enhancement near the $\sqrt{s}_\mathrm{th}$. It also turns out that, in order to reproduce the data, we have the vector coupling constants $g_{K^*S_{11}(1535)\Lambda}=(7.0\sim9.0)$ and $g_{K^*S_{11}(1650)\Lambda}=(5.0\sim6.0)$.
1406.3288
John Heal
Malcolm Fairbairn and John Heal
Complementarity of Dark Matter Searches at Resonance
7 pages, 9 figures
Phys. Rev. D 90, 115019 (2014)
10.1103/PhysRevD.90.115019
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider models of dark matter where the couplings between the standard model and the dark sector fall at resonance due to kinematics and direct detection experiments become insensitive. To be specific, we consider a simple model of 100 GeV - TeV scale dark matter coupled to the standard model via a vector boson. We explore whether it will be possible to exclude such regions of the parameter space using future observations of dijet rates at the LHC and CTA and AMS observations of the Galactic Centre.
[ { "created": "Thu, 12 Jun 2014 17:03:27 GMT", "version": "v1" }, { "created": "Thu, 26 Jun 2014 16:38:14 GMT", "version": "v2" }, { "created": "Wed, 24 Sep 2014 16:43:50 GMT", "version": "v3" }, { "created": "Thu, 15 Jan 2015 16:19:02 GMT", "version": "v4" } ]
2015-01-16
[ [ "Fairbairn", "Malcolm", "" ], [ "Heal", "John", "" ] ]
We consider models of dark matter where the couplings between the standard model and the dark sector fall at resonance due to kinematics and direct detection experiments become insensitive. To be specific, we consider a simple model of 100 GeV - TeV scale dark matter coupled to the standard model via a vector boson. We explore whether it will be possible to exclude such regions of the parameter space using future observations of dijet rates at the LHC and CTA and AMS observations of the Galactic Centre.
hep-ph/0605145
Xavier Calmet
Xavier Calmet
Grand Unification on Noncommutative Spacetime
6 pages, published version
Eur.Phys.J.C50:109-112,2007
10.1140/epjc/s10052-006-0191-5
null
hep-ph hep-th
null
We compute the beta-functions of the standard model formulated on a noncommutative spacetime. If we assume that the scale for spacetime noncommutativity is of the order of 2.2 \times 10^{15} GeV we find that the three gauge couplings of the standard model merge at a scale of 2.3 \times 10^{17} GeV. The proton lifetime is thus much longer than in conventional unification models.
[ { "created": "Fri, 12 May 2006 09:19:40 GMT", "version": "v1" }, { "created": "Thu, 22 Mar 2007 10:30:38 GMT", "version": "v2" } ]
2008-11-26
[ [ "Calmet", "Xavier", "" ] ]
We compute the beta-functions of the standard model formulated on a noncommutative spacetime. If we assume that the scale for spacetime noncommutativity is of the order of 2.2 \times 10^{15} GeV we find that the three gauge couplings of the standard model merge at a scale of 2.3 \times 10^{17} GeV. The proton lifetime is thus much longer than in conventional unification models.
0805.2825
Bogdan Malaescu I.
Bogdan Malaescu
Improved alpha_s from Tau Decays
4pages, 1 figure, Contribution to the proceedings of Moriond 2008, QCD session
null
null
LAL 08-54
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present an update of the measurement of alpha_s(m_tau) from ALEPH tau hadronic spectral functions. We report a study of the perturbative prediction(s) showing that the fixed-order perturbation theory manifests convergence problems not presented in the contour-improved calculation. Potential systematic effects from quark-hadron duality violations are estimated to be within the quoted systematic errors. The fit result is alpha_s(m_tau) = 0.344 +- 0.005 +- 0.007, where the first error is experimental and the second theoretical. After evolution, the alpha_s(M_Z) determined from tau data is the most precise one to date, in agreement with the corresponding NNNLO value derived from Z decays.
[ { "created": "Mon, 19 May 2008 10:18:27 GMT", "version": "v1" } ]
2008-05-20
[ [ "Malaescu", "Bogdan", "" ] ]
We present an update of the measurement of alpha_s(m_tau) from ALEPH tau hadronic spectral functions. We report a study of the perturbative prediction(s) showing that the fixed-order perturbation theory manifests convergence problems not presented in the contour-improved calculation. Potential systematic effects from quark-hadron duality violations are estimated to be within the quoted systematic errors. The fit result is alpha_s(m_tau) = 0.344 +- 0.005 +- 0.007, where the first error is experimental and the second theoretical. After evolution, the alpha_s(M_Z) determined from tau data is the most precise one to date, in agreement with the corresponding NNNLO value derived from Z decays.
2212.09795
Avirup Ghosh
Koushik Dutta, Avirup Ghosh, Arpan Kar, Biswarup Mukhopadhyaya
MeV to multi-TeV thermal WIMPs: most conservative limits
Matches the published version in JCAP 21 pages, 7 figures
JCAP 08 (2023) 071
10.1088/1475-7516/2023/08/071
CQUeST-2022-0706
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a weakly interacting massive particle (WIMP) dark matter (DM) annihilating into all possible Standard Model (SM) particle pairs, including the SM neutrinos, via $s$-wave processes and derive the branching ratio independent upper limit on the total annihilation cross-section $\langle \sigma v \rangle$ using the data of CMB, gamma-ray, cosmic-ray and several neutrino observations. For conservative choices of all relevant astrophysical parameters, we obtain upper limits of $10^{-23}-10^{-25}\,{\rm cm}^3{\rm s}^{-1}$ on the total $\langle \sigma v \rangle$ for the WIMP mass range $10\,{\rm MeV}-100\,{\rm TeV}$, thus making the entire mass range consistent with the observed relic density. An important input that goes into our analysis is the assumption that thermal WIMPs can have significant coupling to the SM neutrinos.
[ { "created": "Mon, 19 Dec 2022 19:08:52 GMT", "version": "v1" }, { "created": "Wed, 30 Aug 2023 18:06:51 GMT", "version": "v2" } ]
2023-09-01
[ [ "Dutta", "Koushik", "" ], [ "Ghosh", "Avirup", "" ], [ "Kar", "Arpan", "" ], [ "Mukhopadhyaya", "Biswarup", "" ] ]
We consider a weakly interacting massive particle (WIMP) dark matter (DM) annihilating into all possible Standard Model (SM) particle pairs, including the SM neutrinos, via $s$-wave processes and derive the branching ratio independent upper limit on the total annihilation cross-section $\langle \sigma v \rangle$ using the data of CMB, gamma-ray, cosmic-ray and several neutrino observations. For conservative choices of all relevant astrophysical parameters, we obtain upper limits of $10^{-23}-10^{-25}\,{\rm cm}^3{\rm s}^{-1}$ on the total $\langle \sigma v \rangle$ for the WIMP mass range $10\,{\rm MeV}-100\,{\rm TeV}$, thus making the entire mass range consistent with the observed relic density. An important input that goes into our analysis is the assumption that thermal WIMPs can have significant coupling to the SM neutrinos.
hep-ph/0009043
null
Jihn E. Kim and Bumseok Kyae
The $\mu$ and soft masses from the intermediate scale brane with non-factorizable geometry
14 pages, comments and references added
Phys.Lett. B500 (2001) 313-319
10.1016/S0370-2693(01)00087-9
SNUTP 00/023
hep-ph
null
The proton decay problem and the negative brane tension problem in the original Randall-Sundrum model can be resolved by interpreting the Planck scale brane as the visible sector brane. The hierarchy problem is resolved with supersymmetry, and the TeV scales for soft masses and $\mu$ in supersymmetric models are generated by the physics at the intermediate scale ($\sim 10^{11-13}$ GeV) brane.
[ { "created": "Tue, 5 Sep 2000 00:28:14 GMT", "version": "v1" }, { "created": "Wed, 20 Sep 2000 11:44:04 GMT", "version": "v2" }, { "created": "Thu, 14 Dec 2000 06:59:57 GMT", "version": "v3" } ]
2009-10-31
[ [ "Kim", "Jihn E.", "" ], [ "Kyae", "Bumseok", "" ] ]
The proton decay problem and the negative brane tension problem in the original Randall-Sundrum model can be resolved by interpreting the Planck scale brane as the visible sector brane. The hierarchy problem is resolved with supersymmetry, and the TeV scales for soft masses and $\mu$ in supersymmetric models are generated by the physics at the intermediate scale ($\sim 10^{11-13}$ GeV) brane.
1606.02970
Milena Soltysiak
Milena Soltysiak, Thomas Wolkanowski and Francesco Giacosa
A study of the resonances $K_{0}^{*}(800)$ and $K_{0}^{*}(1430)$
Based on the presentation given at FAIRNESS 2016, Workshop for young scientists with research interests focused on physics at FAIR, 14-19 February 2016, Garmisch-Partenkirchen, Germany. 5 pages, 5 figures
null
10.1088/1742-6596/742/1/012014
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the scalar kaonic states $K_{0}^{\ast}(800)$ and $K_{0}^{\ast}(1430)$ by using a relativistic QFT Lagrangian in which only a single kaonic field corresponding to the well-established scalar state $K_{0}^{\ast}(1430)$ is considered and in which both derivative and non-derivative interaction terms are taken into account. Even if the scalar spectral function shows a unique peak close to $1.4$ GeV, we find two poles in the complex plane: $1.413\pm0.002-i(0.127\pm0.003)$ GeV, which is related to the seed quark-antiquark state $K_{0}^{\ast}(1430),$ and $0.746\pm0.019-i(262\pm0.014)$ GeV, which is an additional companion pole related to $K_{0}^{\ast}(800)$. As a further investigation for increasing $N_{c}$ confirms, $K_{0}^{\ast}(800)$ emerges as a dynamically generated four-quark object as a consequence of pion-kaon loops.
[ { "created": "Thu, 9 Jun 2016 14:07:38 GMT", "version": "v1" } ]
2016-11-03
[ [ "Soltysiak", "Milena", "" ], [ "Wolkanowski", "Thomas", "" ], [ "Giacosa", "Francesco", "" ] ]
We study the scalar kaonic states $K_{0}^{\ast}(800)$ and $K_{0}^{\ast}(1430)$ by using a relativistic QFT Lagrangian in which only a single kaonic field corresponding to the well-established scalar state $K_{0}^{\ast}(1430)$ is considered and in which both derivative and non-derivative interaction terms are taken into account. Even if the scalar spectral function shows a unique peak close to $1.4$ GeV, we find two poles in the complex plane: $1.413\pm0.002-i(0.127\pm0.003)$ GeV, which is related to the seed quark-antiquark state $K_{0}^{\ast}(1430),$ and $0.746\pm0.019-i(262\pm0.014)$ GeV, which is an additional companion pole related to $K_{0}^{\ast}(800)$. As a further investigation for increasing $N_{c}$ confirms, $K_{0}^{\ast}(800)$ emerges as a dynamically generated four-quark object as a consequence of pion-kaon loops.
2212.03572
Alessandro Giachino
Etienne Blanco, Alessandro Giachino, Andreas van Hameren, Piotr Kotko
One-loop gauge invariant amplitudes with a space-like gluon
null
null
null
IFJPAN-IV-2022-20
hep-ph
http://creativecommons.org/licenses/by/4.0/
Nowadays the particle physics has entered an era where high precision calculations are required in order to compare the theoretical predictions with the experimental data. In this paper, we explicitly compute the virtual contributions for the space-like one-jet processes, $\procgg,\procqq,\procH$ and $\procee$ within the auxiliary parton method. Our results, which are expected to play an important role in high precision description of small $x$ physics, explicitly confirm the conjecture developed in Ref. \cite{vanHameren:2022mtk}, thus helping to bridge the gap between lowest order calculations and NLO corrections within hybrid $k_T$-factorization scheme.
[ { "created": "Wed, 7 Dec 2022 11:16:40 GMT", "version": "v1" }, { "created": "Tue, 13 Dec 2022 13:36:23 GMT", "version": "v2" }, { "created": "Thu, 6 Apr 2023 10:32:09 GMT", "version": "v3" } ]
2023-04-07
[ [ "Blanco", "Etienne", "" ], [ "Giachino", "Alessandro", "" ], [ "van Hameren", "Andreas", "" ], [ "Kotko", "Piotr", "" ] ]
Nowadays the particle physics has entered an era where high precision calculations are required in order to compare the theoretical predictions with the experimental data. In this paper, we explicitly compute the virtual contributions for the space-like one-jet processes, $\procgg,\procqq,\procH$ and $\procee$ within the auxiliary parton method. Our results, which are expected to play an important role in high precision description of small $x$ physics, explicitly confirm the conjecture developed in Ref. \cite{vanHameren:2022mtk}, thus helping to bridge the gap between lowest order calculations and NLO corrections within hybrid $k_T$-factorization scheme.
1607.03838
Spencer Klein
Spencer R. Klein, Joakim Nystrand, Janet Seger, Yuri Gorbunov and Joey Butterworth
STARlight: A Monte Carlo simulation program for ultra-peripheral collisions of relativistic ions
15 pages; final version with a few minor bugs corrected
Comput.Phys.Commun. 212 (2017) 258-268
10.1016/j.cpc.2016.10.016
null
hep-ph nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Ultra-peripheral collisions (UPCs) have been a significant source of study at RHIC and the LHC. In these collisions, the two colliding nuclei interact electromagnetically, via two-photon or photonuclear interactions, but not hadronically; they effectively miss each other. Photonuclear interactions produce vector meson states or more general photonuclear final states, while two-photon interactions can produce lepton or meson pairs, or single mesons. In these interactions, the collision geometry plays a major role. We present a program, STARlight, that calculates the cross-sections for a variety of UPC final states and also creates, via Monte Carlo simulation, events for use in determining detector efficiency.
[ { "created": "Wed, 13 Jul 2016 17:53:19 GMT", "version": "v1" }, { "created": "Tue, 20 Dec 2016 00:33:08 GMT", "version": "v2" } ]
2017-04-18
[ [ "Klein", "Spencer R.", "" ], [ "Nystrand", "Joakim", "" ], [ "Seger", "Janet", "" ], [ "Gorbunov", "Yuri", "" ], [ "Butterworth", "Joey", "" ] ]
Ultra-peripheral collisions (UPCs) have been a significant source of study at RHIC and the LHC. In these collisions, the two colliding nuclei interact electromagnetically, via two-photon or photonuclear interactions, but not hadronically; they effectively miss each other. Photonuclear interactions produce vector meson states or more general photonuclear final states, while two-photon interactions can produce lepton or meson pairs, or single mesons. In these interactions, the collision geometry plays a major role. We present a program, STARlight, that calculates the cross-sections for a variety of UPC final states and also creates, via Monte Carlo simulation, events for use in determining detector efficiency.
hep-ph/0008035
V. M. Mostepanenko
V.M.Mostepanenko, M.Novello
Possible violation of Newtonian gravitational law at small distances and constraints on it from the Casimir effect
7 pages, 1 figure
null
null
null
hep-ph
null
The recent ideas that the gravitational and gauge interactions become united at the weak scale lead to Yukawa-type corrections to the Newtonian gravitational law at small distances. We briefly summarize the best constraints on these corrections obtained recently from the experiments on the measurement of the Casimir force. The new constraints on the Yukawa-type interaction are derived from the latest Casimir force measurement between a large gold coated sphere and flat disk using an atomic force microscope. The obtained constraints are stronger up to 19 times comparing the previous experiment with aluminum surfaces and up to 4500 times comparing the Casimir force measurements between dielectrics. The application range of constraints obtained by means of an atomic force microscope is extended.
[ { "created": "Thu, 3 Aug 2000 17:43:50 GMT", "version": "v1" } ]
2007-05-23
[ [ "Mostepanenko", "V. M.", "" ], [ "Novello", "M.", "" ] ]
The recent ideas that the gravitational and gauge interactions become united at the weak scale lead to Yukawa-type corrections to the Newtonian gravitational law at small distances. We briefly summarize the best constraints on these corrections obtained recently from the experiments on the measurement of the Casimir force. The new constraints on the Yukawa-type interaction are derived from the latest Casimir force measurement between a large gold coated sphere and flat disk using an atomic force microscope. The obtained constraints are stronger up to 19 times comparing the previous experiment with aluminum surfaces and up to 4500 times comparing the Casimir force measurements between dielectrics. The application range of constraints obtained by means of an atomic force microscope is extended.
1104.4642
Holger Frits Bech Nielsen
H. B. Nielsen
The New Dijet Particle in the Tevatron IS the Higgs
A note on the recent photon photon peak at LHC were added together with the name of a person in the acknowledgement corrected
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The newly found \cite{CDFnew} dijet peak in the 120 GeV to 160 GeV mass region produced in co-production with W IS actually a Higgs Boson in spite of the expectation of a different decay pattern for most Higgses. Our point, however, is that the bound state of 6t + 6$\bar{t}$, which we have put forward already in several articles \cite{boundfirst}\cite{bound} \cite{dark}\cite{hierarchybound}, easily could be lighter - possibly much lighter - than half the Higgs mass. Higgs would in this case decay dominantly to two of our bound states. If these bound states were indeed very light (say around 10 GeV) their decay products into hadrons would like two jets, one for each bound state. Even a very small mass for our bound state is not unexpected isofar as it is part of our model that especially the top-quark-Yukawa coupling is being tuned so as to make precisely this bound state of $6t + 6\bar{t}$ become (approximately) massless. This tuning is a consequence of our Multiple Point Principle \cite{old} \cite{SIMPP} which states that the realized parameter/coupling values correspond to having a maximal set of degenerate vacua. Even the very recent LHC-peak in photon photon might be fitted to our model.
[ { "created": "Sun, 24 Apr 2011 16:26:56 GMT", "version": "v1" }, { "created": "Mon, 2 May 2011 16:45:08 GMT", "version": "v2" }, { "created": "Mon, 9 May 2011 19:53:30 GMT", "version": "v3" }, { "created": "Sat, 14 May 2011 12:42:19 GMT", "version": "v4" } ]
2011-05-17
[ [ "Nielsen", "H. B.", "" ] ]
The newly found \cite{CDFnew} dijet peak in the 120 GeV to 160 GeV mass region produced in co-production with W IS actually a Higgs Boson in spite of the expectation of a different decay pattern for most Higgses. Our point, however, is that the bound state of 6t + 6$\bar{t}$, which we have put forward already in several articles \cite{boundfirst}\cite{bound} \cite{dark}\cite{hierarchybound}, easily could be lighter - possibly much lighter - than half the Higgs mass. Higgs would in this case decay dominantly to two of our bound states. If these bound states were indeed very light (say around 10 GeV) their decay products into hadrons would like two jets, one for each bound state. Even a very small mass for our bound state is not unexpected isofar as it is part of our model that especially the top-quark-Yukawa coupling is being tuned so as to make precisely this bound state of $6t + 6\bar{t}$ become (approximately) massless. This tuning is a consequence of our Multiple Point Principle \cite{old} \cite{SIMPP} which states that the realized parameter/coupling values correspond to having a maximal set of degenerate vacua. Even the very recent LHC-peak in photon photon might be fitted to our model.
hep-ph/9908278
G. S. Krishnaswami
S. G. Rajeev (University of Rochester)
Valence Parton Distribution Functions from Quantum ChromoDynamics
5 pages, RevTex
null
null
null
hep-ph
null
We show that two dimensional QCD can, to a good approximation, describe the hadronic structure functions measured in Deep Inelastic Scattering. We transform this theory into a new form, Quantum HadronDynamics (QHD), whose semi-classical approximation is closer to nature. The Baryon is then a topological soliton, and its structure function can be predicted by a variational principle. This prediction can be tested by comparison with measurements of neutrino scattering cross-sections.
[ { "created": "Fri, 6 Aug 1999 03:32:36 GMT", "version": "v1" } ]
2007-05-23
[ [ "Rajeev", "S. G.", "", "University of Rochester" ] ]
We show that two dimensional QCD can, to a good approximation, describe the hadronic structure functions measured in Deep Inelastic Scattering. We transform this theory into a new form, Quantum HadronDynamics (QHD), whose semi-classical approximation is closer to nature. The Baryon is then a topological soliton, and its structure function can be predicted by a variational principle. This prediction can be tested by comparison with measurements of neutrino scattering cross-sections.
0809.0846
Sergei Chekanov V.
R.E. Blair, S.Chekanov, G.Heinrich, A.Lipatov, N.Zotov
Direct photon production at HERA, the Tevatron and the LHC
16 pages, 18 figures, Proceedings of the HERA-LHC workshop (CERN-DESY), 2007-2008
null
null
ANL-HEP-CP-08-52, IPPP/08/64, DCPT/08/128
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We review several most recent prompt-photon measurements at HERA and the Tevatron and discuss their implication for future measurements at the LHC. A comparison to Monte Carlo models, as well as to NLO QCD predictions based on the standard DGLAP and the kT-factorization approaches is discussed. Effects from renormalization and factorization scale uncertainties, as well as uncertainties on the gluon density distribution inside a proton are discussed.
[ { "created": "Thu, 4 Sep 2008 16:07:42 GMT", "version": "v1" }, { "created": "Thu, 5 Mar 2009 15:12:11 GMT", "version": "v2" } ]
2009-03-05
[ [ "Blair", "R. E.", "" ], [ "Chekanov", "S.", "" ], [ "Heinrich", "G.", "" ], [ "Lipatov", "A.", "" ], [ "Zotov", "N.", "" ] ]
We review several most recent prompt-photon measurements at HERA and the Tevatron and discuss their implication for future measurements at the LHC. A comparison to Monte Carlo models, as well as to NLO QCD predictions based on the standard DGLAP and the kT-factorization approaches is discussed. Effects from renormalization and factorization scale uncertainties, as well as uncertainties on the gluon density distribution inside a proton are discussed.
2302.07687
Vanamali Shastry C
Vanamali Shastry and Francesco Giacosa
Radiative production and decays of the exotic $\eta_1^\prime(1855)$ and its siblings
14 pages, matches published version
null
10.1016/j.nuclphysa.2023.122683
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the production of the light $J^{PC}=1^{-+}$ hybrid isoscalars $\eta_1^\prime(1855)$ and the yet undiscovered $\eta_1^{hyb}(1660)$ as intermediate states in the radiative decays of the charmonium ($J/\psi$) to two conventional mesons using a flavor symmetric Lagrangian. For this purpose, we use the $J/\psi\to\gamma\eta_1^\prime(1855)\to\gamma\eta\eta^\prime$ process as the reference. We find that some of the decay channels have branching ratios similar to or larger than that of the $\gamma\eta\eta^\prime$ channel and are sensitive to the mixing between the hybrid isoscalars. We propose that relatively stable $\gamma\eta f_1(1285)$ channel be explored for the presence of the light hybrid isoscalar $\eta_1^{hyb}(1660)$. We also exploit the strong decay channels containing at least one vector meson to study the radiative decays of the whole hybrid nonet $\{\pi_1(1600),K_1^{hyb}(1750),\eta_1^{hyb}(1660),\eta_1'(1855)\}$. We find that the hybrids cannot radiatively decay into the $I=0$ pseudoscalars. Furthermore, the vector decay channels ($(\rho/\omega/\phi)\gamma$) of the hybrid isoscalars are sensitive to the strangeness content of the hybrids. We also provide estimates for the branching fractions for the radiative production and partial widths for the radiative decays of the hybrids.
[ { "created": "Wed, 15 Feb 2023 14:26:12 GMT", "version": "v1" }, { "created": "Thu, 10 Aug 2023 18:13:38 GMT", "version": "v2" } ]
2023-08-14
[ [ "Shastry", "Vanamali", "" ], [ "Giacosa", "Francesco", "" ] ]
We study the production of the light $J^{PC}=1^{-+}$ hybrid isoscalars $\eta_1^\prime(1855)$ and the yet undiscovered $\eta_1^{hyb}(1660)$ as intermediate states in the radiative decays of the charmonium ($J/\psi$) to two conventional mesons using a flavor symmetric Lagrangian. For this purpose, we use the $J/\psi\to\gamma\eta_1^\prime(1855)\to\gamma\eta\eta^\prime$ process as the reference. We find that some of the decay channels have branching ratios similar to or larger than that of the $\gamma\eta\eta^\prime$ channel and are sensitive to the mixing between the hybrid isoscalars. We propose that relatively stable $\gamma\eta f_1(1285)$ channel be explored for the presence of the light hybrid isoscalar $\eta_1^{hyb}(1660)$. We also exploit the strong decay channels containing at least one vector meson to study the radiative decays of the whole hybrid nonet $\{\pi_1(1600),K_1^{hyb}(1750),\eta_1^{hyb}(1660),\eta_1'(1855)\}$. We find that the hybrids cannot radiatively decay into the $I=0$ pseudoscalars. Furthermore, the vector decay channels ($(\rho/\omega/\phi)\gamma$) of the hybrid isoscalars are sensitive to the strangeness content of the hybrids. We also provide estimates for the branching fractions for the radiative production and partial widths for the radiative decays of the hybrids.
hep-ph/0207184
Jae Sik Lee
Francesca Borzumati and Jae Sik Lee
Novel constraints on $\Delta L=1$ interactions from neutrino masses
19 pages, 4 figures, and 2 tables. Version to appear in Phys. Rev. D
Phys.Rev. D66 (2002) 115012
10.1103/PhysRevD.66.115012
KEK-TH-831
hep-ph
null
We reanalyze the constraints imposed on lepton-number violating interactions by radiative contributions to neutrino masses at the one- and two-loop level in supersymmetric models without R-parity. The interactions considered are the $\Delta L=1$ superpotential operators $\lambda_{ijk} L_i L_j E^c_k$ and $\lambda^\prime_{ijk} L_i Q_j D^c_k$, and the $\Delta L=1$ soft terms $A_{ijk} \tilde{L}_i \tilde{L}_j \tilde{E}^c_k$ and $A_{ijk}^\prime \tilde{L}_i \tilde{Q}_j \tilde{D}^c_k$. It is shown how the constraints on the couplings $\lambda_{ijk}$ and $\lambda^\prime_{ijk}$ coming from the one-loop analysis can be evaded. In such a case, the two-loop contributions to neutrino masses become important. The combined one- and two-loop analysis yields constraints on the couplings $\lambda_{i33}$ and $\lambda^\prime_{i33}$ that are rather difficult to escape. The two-loop analysis yields also new constraints on $A_{i33}$ and $A^\prime_{i33}$, which are not bounded at the one-loop level. More freedom remains for couplings $\lambda_{ijk}$, $\lambda^\prime_{ijk}$, and $A_{ijk}$, $A^\prime_{ijk}$, when $j$ and $k$ are first- or second-generation indices.
[ { "created": "Mon, 15 Jul 2002 14:51:19 GMT", "version": "v1" }, { "created": "Tue, 26 Nov 2002 13:47:48 GMT", "version": "v2" } ]
2009-11-07
[ [ "Borzumati", "Francesca", "" ], [ "Lee", "Jae Sik", "" ] ]
We reanalyze the constraints imposed on lepton-number violating interactions by radiative contributions to neutrino masses at the one- and two-loop level in supersymmetric models without R-parity. The interactions considered are the $\Delta L=1$ superpotential operators $\lambda_{ijk} L_i L_j E^c_k$ and $\lambda^\prime_{ijk} L_i Q_j D^c_k$, and the $\Delta L=1$ soft terms $A_{ijk} \tilde{L}_i \tilde{L}_j \tilde{E}^c_k$ and $A_{ijk}^\prime \tilde{L}_i \tilde{Q}_j \tilde{D}^c_k$. It is shown how the constraints on the couplings $\lambda_{ijk}$ and $\lambda^\prime_{ijk}$ coming from the one-loop analysis can be evaded. In such a case, the two-loop contributions to neutrino masses become important. The combined one- and two-loop analysis yields constraints on the couplings $\lambda_{i33}$ and $\lambda^\prime_{i33}$ that are rather difficult to escape. The two-loop analysis yields also new constraints on $A_{i33}$ and $A^\prime_{i33}$, which are not bounded at the one-loop level. More freedom remains for couplings $\lambda_{ijk}$, $\lambda^\prime_{ijk}$, and $A_{ijk}$, $A^\prime_{ijk}$, when $j$ and $k$ are first- or second-generation indices.
1904.08810
Ketan Patel
Wilfried Buchmuller, Ketan M. Patel
Proton decay in flux compactifications
26 pages, 3 figures, 2 tables
JHEP 1905 (2019) 196
10.1007/JHEP05(2019)196
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study proton decay in a six-dimensional orbifold GUT model with gauge group $SO(10)\times U(1)_A$. Magnetic $U(1)_A$ flux in the compact dimensions determines the multiplicity of quark-lepton generations, and it also breaks supersymmetry by giving universal GUT scale masses to scalar quarks and leptons. The model can successfully account for quark and lepton masses and mixings. Our analysis of proton decay leads to the conclusion that the proton lifetime must be close to the current experimental lower bound. Moreover, we find that the branching ratios for the decay channels $p \rightarrow e^+\pi^0$ and $p\rightarrow \mu^+\pi^0$ are of similar size, in fact the latter one can even be dominant. This is due to flavour non-diagonal couplings of heavy vector bosons together with large off-diagonal Higgs couplings, which appears to be a generic feature of flux compactifications.
[ { "created": "Thu, 18 Apr 2019 14:37:09 GMT", "version": "v1" } ]
2019-05-30
[ [ "Buchmuller", "Wilfried", "" ], [ "Patel", "Ketan M.", "" ] ]
We study proton decay in a six-dimensional orbifold GUT model with gauge group $SO(10)\times U(1)_A$. Magnetic $U(1)_A$ flux in the compact dimensions determines the multiplicity of quark-lepton generations, and it also breaks supersymmetry by giving universal GUT scale masses to scalar quarks and leptons. The model can successfully account for quark and lepton masses and mixings. Our analysis of proton decay leads to the conclusion that the proton lifetime must be close to the current experimental lower bound. Moreover, we find that the branching ratios for the decay channels $p \rightarrow e^+\pi^0$ and $p\rightarrow \mu^+\pi^0$ are of similar size, in fact the latter one can even be dominant. This is due to flavour non-diagonal couplings of heavy vector bosons together with large off-diagonal Higgs couplings, which appears to be a generic feature of flux compactifications.
1612.06194
Ana M. Teixeira
Ana M. Teixeira
Lepton flavour violation and neutrino physics: beyond the Standard Model
8 pages, 4 figures, proceedings of the "28th Rencontres de Blois - Particle Physics and Cosmology", Blois, 29 May - 3 June 2016. arXiv admin note: text overlap with arXiv:1612.05561
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If observed, charged lepton flavour violation is a clear sign of new physics - beyond the Standard Model minimally extended to accommodate neutrino oscillation data. After a brief review of several charged lepton flavour violation observables and their current experimental status, we consider distinct extensions of the Standard Model which could potentially give rise to observable signals, focusing on the case of models in which the mechanism of neutrino mass generation is the common source of neutral and charged lepton flavour violation.
[ { "created": "Mon, 19 Dec 2016 14:23:50 GMT", "version": "v1" } ]
2016-12-20
[ [ "Teixeira", "Ana M.", "" ] ]
If observed, charged lepton flavour violation is a clear sign of new physics - beyond the Standard Model minimally extended to accommodate neutrino oscillation data. After a brief review of several charged lepton flavour violation observables and their current experimental status, we consider distinct extensions of the Standard Model which could potentially give rise to observable signals, focusing on the case of models in which the mechanism of neutrino mass generation is the common source of neutral and charged lepton flavour violation.
hep-ph/0507045
Stuart Raby
Radovan Dermisek and Stuart Raby
Bi-large Neutrino Mixing and CP violation in an SO(10) SUSY GUT for Fermion Masses
16 pages, resubmitted as a PLB letter, appendices were removed
Phys.Lett. B622 (2005) 327-338
10.1016/j.physletb.2005.07.018
OHSTPY-HEP-T-05-002, UCD-05-08
hep-ph
null
We construct a simple SO(10) SUSY GUT with $D_3$ family symmetry and low energy R parity. The model describes fermion mass matrices with 14 parameters and gives excellent fits to 20 observable masses and mixing angles in both quark and lepton sectors, giving 6 predictions. Bi-large neutrino mixing is obtained with hierarchical quark and lepton Yukawa matrices; thus avoiding the possibility of large lepton flavor violation. The model naturally predicts small 1-3 neutrino mixing, $\sin \theta_{13} \simeq 0.05$, and a CP violating phase $\delta$ close to $\pi/2$. Among other interesting predictions is a tiny effective Majorana mass for neutrinoless double-beta decay. Leptogenesis is also possible with the decay of the lightest right-handed neutrino giving an acceptable CP violating asymmetry $\epsilon_1$ of order $10^{-6}$, {\em and with the correct sign for the resultant baryon asymmetry}. We also show how similar models with the non-abelian symmetry groups SU(2) or $D_4$, instead of $D_3$, can be constructed.
[ { "created": "Mon, 4 Jul 2005 15:59:27 GMT", "version": "v1" }, { "created": "Sun, 10 Jul 2005 15:42:14 GMT", "version": "v2" } ]
2010-04-05
[ [ "Dermisek", "Radovan", "" ], [ "Raby", "Stuart", "" ] ]
We construct a simple SO(10) SUSY GUT with $D_3$ family symmetry and low energy R parity. The model describes fermion mass matrices with 14 parameters and gives excellent fits to 20 observable masses and mixing angles in both quark and lepton sectors, giving 6 predictions. Bi-large neutrino mixing is obtained with hierarchical quark and lepton Yukawa matrices; thus avoiding the possibility of large lepton flavor violation. The model naturally predicts small 1-3 neutrino mixing, $\sin \theta_{13} \simeq 0.05$, and a CP violating phase $\delta$ close to $\pi/2$. Among other interesting predictions is a tiny effective Majorana mass for neutrinoless double-beta decay. Leptogenesis is also possible with the decay of the lightest right-handed neutrino giving an acceptable CP violating asymmetry $\epsilon_1$ of order $10^{-6}$, {\em and with the correct sign for the resultant baryon asymmetry}. We also show how similar models with the non-abelian symmetry groups SU(2) or $D_4$, instead of $D_3$, can be constructed.
1903.05703
Abhishek Pal
Abhishek Pal and Qaisar Shafi
Supersymmetric $SU(5) \times U(1)_\chi$ and the Weak Gravity Conjecture
6 pages, 6 figures
Phys. Rev. D 100, 043526 (2019)
10.1103/PhysRevD.100.043526
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The gauge symmetry $SU(5) \times U(1)_\chi$ is the unique maximal subgroup of SO(10) which retains manifest unification at $M_{GUT}$ of the Standard Model gauge couplings, especially if low scale supersymmetry is present. The spontaneous breaking of $U(1)_\chi$ at some intermediate scale leaves unbroken a $Z_2$ symmetry which is precisely `matter' parity. This yields a stable supersymmetric dark matter particle as well as topologically stable cosmic strings. Motivated by the weak gravity conjecture we impose unification of $SU(5)$ and $U(1)_\chi$ at an ultraviolet cutoff $\Lambda \sim \alpha_\Lambda ^{1/2} M_{P} \approx 5 \times 10^{17}$ GeV, where $\alpha_\Lambda$ denotes the $SU(5)$ gauge coupling at $\Lambda$ and $M_P \approx 2.4 \times 10^{18}$ GeV is the reduced Planck Scale. The impact of dimension five operators suppressed by $\Lambda$ on gauge coupling unification, proton lifetime estimates and $b-\tau$ Yukawa unification is discussed. In particular, the gauge boson mediated proton decay into $e^+\pi^0$ can lie within the $2-\sigma$ sensitivity of HyperKamiokande. We also discuss how the intermediate scale strings may survive inflation while the $SU(5)$ monopoles are inflated away. The unbroken $Z_2$ symmetry provides an intriguing link between dark matter, black holes carrying `quantum hair' and cosmic strings.
[ { "created": "Wed, 13 Mar 2019 20:01:10 GMT", "version": "v1" } ]
2019-08-21
[ [ "Pal", "Abhishek", "" ], [ "Shafi", "Qaisar", "" ] ]
The gauge symmetry $SU(5) \times U(1)_\chi$ is the unique maximal subgroup of SO(10) which retains manifest unification at $M_{GUT}$ of the Standard Model gauge couplings, especially if low scale supersymmetry is present. The spontaneous breaking of $U(1)_\chi$ at some intermediate scale leaves unbroken a $Z_2$ symmetry which is precisely `matter' parity. This yields a stable supersymmetric dark matter particle as well as topologically stable cosmic strings. Motivated by the weak gravity conjecture we impose unification of $SU(5)$ and $U(1)_\chi$ at an ultraviolet cutoff $\Lambda \sim \alpha_\Lambda ^{1/2} M_{P} \approx 5 \times 10^{17}$ GeV, where $\alpha_\Lambda$ denotes the $SU(5)$ gauge coupling at $\Lambda$ and $M_P \approx 2.4 \times 10^{18}$ GeV is the reduced Planck Scale. The impact of dimension five operators suppressed by $\Lambda$ on gauge coupling unification, proton lifetime estimates and $b-\tau$ Yukawa unification is discussed. In particular, the gauge boson mediated proton decay into $e^+\pi^0$ can lie within the $2-\sigma$ sensitivity of HyperKamiokande. We also discuss how the intermediate scale strings may survive inflation while the $SU(5)$ monopoles are inflated away. The unbroken $Z_2$ symmetry provides an intriguing link between dark matter, black holes carrying `quantum hair' and cosmic strings.
hep-ph/9708392
David A. Kosower
David A. Kosower
Extracting Parton Densities from Collider Data
One reference added, some text added, one equation corrected
Nucl.Phys. B520 (1998) 263-278
10.1016/S0550-3213(98)00082-0
Saclay-SPhT/T97-101
hep-ph
null
Collider data can play an important role in determining the parton distribution functions of the nucleon. I present a formalism which makes it possible to use next-to-leading order calculations in such a determination, while minimizing the amount of numerical computation required.
[ { "created": "Mon, 18 Aug 1997 15:42:35 GMT", "version": "v1" }, { "created": "Tue, 18 Nov 1997 13:38:38 GMT", "version": "v2" } ]
2009-10-30
[ [ "Kosower", "David A.", "" ] ]
Collider data can play an important role in determining the parton distribution functions of the nucleon. I present a formalism which makes it possible to use next-to-leading order calculations in such a determination, while minimizing the amount of numerical computation required.
hep-ph/9904504
A. Perez-Lorenzana
A. P\'erez-Lorenzana and R. N. Mohapatra
Effect of Extra Dimensions on Gauge Coupling Unification
LaTeX file, uses epsf style, 29 pages, five PS figures. Minor changes. Some scenarios removed (version to appear in Nucl Phys B)
Nucl.Phys.B559:255,1999
10.1016/S0550-3213(99)00442-3
UMD-PP-99-107
hep-ph hep-th
null
The effects of extra dimensions on gauge coupling unification is studied. We start with a comparison between power law running of the gauge couplings in models with extra dimensions and logarithmic running that happens in many realistic cases. We then discuss the effect of extra dimensions on various classes of unification models. We identify products of evolution coefficients that dictate the profile of unification in different models. We use them to study under what conditions unification of couplings can occur in both one and two step unification models. We find that Kaluza-Klein modes can help generate interesting intermediate scale models with gauge coupling unification such as the minimal left-right models with the seesaw mechanism with a $M_{W_R}\sim 10^{13}$ GeV intermediate scale, useful in understanding neutrino oscillations. We also obtain several examples where the presence of noncanonical normalization of couplings enables us to obtain unification scales around $10^{11}$ GeV. This fits very well into a class of models proposed recently where the string scale is advocated to be at this value from physical arguments.
[ { "created": "Fri, 30 Apr 1999 16:55:10 GMT", "version": "v1" }, { "created": "Thu, 6 May 1999 20:46:40 GMT", "version": "v2" }, { "created": "Mon, 2 Aug 1999 19:55:41 GMT", "version": "v3" } ]
2008-11-26
[ [ "Pérez-Lorenzana", "A.", "" ], [ "Mohapatra", "R. N.", "" ] ]
The effects of extra dimensions on gauge coupling unification is studied. We start with a comparison between power law running of the gauge couplings in models with extra dimensions and logarithmic running that happens in many realistic cases. We then discuss the effect of extra dimensions on various classes of unification models. We identify products of evolution coefficients that dictate the profile of unification in different models. We use them to study under what conditions unification of couplings can occur in both one and two step unification models. We find that Kaluza-Klein modes can help generate interesting intermediate scale models with gauge coupling unification such as the minimal left-right models with the seesaw mechanism with a $M_{W_R}\sim 10^{13}$ GeV intermediate scale, useful in understanding neutrino oscillations. We also obtain several examples where the presence of noncanonical normalization of couplings enables us to obtain unification scales around $10^{11}$ GeV. This fits very well into a class of models proposed recently where the string scale is advocated to be at this value from physical arguments.
0906.5595
Tonnis ter Veldhuis
T.E. Clark, Boyang Liu, S.T. Love, and T. ter Veldhuis
The Standard Model Higgs Boson-Inflaton and Dark Matter
15 pages, 10 figures
Phys.Rev.D80:075019,2009
10.1103/PhysRevD.80.075019
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The standard model Higgs boson can serve as the inflaton field of slow roll inflationary models provided it exhibits a large non-minimal coupling with the gravitational scalar curvature. The Higgs boson self interactions and its couplings with a standard model singlet scalar serving as the source of dark matter are then subject to cosmological constraints. These bounds, which can be more stringent than those arising from vacuum stability and perturbative triviality alone, still allow values for the Higgs boson mass which should be accessible at the LHC. As the Higgs boson coupling to the dark matter strengthens, lower values of the Higgs boson mass consistent with the cosmological data are allowed.
[ { "created": "Tue, 30 Jun 2009 17:58:00 GMT", "version": "v1" } ]
2009-11-05
[ [ "Clark", "T. E.", "" ], [ "Liu", "Boyang", "" ], [ "Love", "S. T.", "" ], [ "ter Veldhuis", "T.", "" ] ]
The standard model Higgs boson can serve as the inflaton field of slow roll inflationary models provided it exhibits a large non-minimal coupling with the gravitational scalar curvature. The Higgs boson self interactions and its couplings with a standard model singlet scalar serving as the source of dark matter are then subject to cosmological constraints. These bounds, which can be more stringent than those arising from vacuum stability and perturbative triviality alone, still allow values for the Higgs boson mass which should be accessible at the LHC. As the Higgs boson coupling to the dark matter strengthens, lower values of the Higgs boson mass consistent with the cosmological data are allowed.
hep-ph/9403280
Yoshiki Kizukuri
Yoshiki Kizukuri and Noriyuki Oshimo
$CP$ violation in minimal supersymmetric standard model
7 pages with 7 figures, TKU-HEP 94/02; IFM 2/94, LaTeX with Elsevir Science Publisher's style file, espcrc2.sty. (To appear in the proceedings of the Third KEK Topical Conference on CP Violation, November 1993) Figures are not included. The complete PostScript file can be obtained by anonymous ftp from ape.sp.u-tokai.ac.jp in the directry
Nucl.Phys.Proc.Suppl.37A:173-180,1994
10.1016/0920-5632(94)90747-1
null
hep-ph
null
$CP$ violating phenomena predicted by the minimal supersymmetric standard model are discussed in a case where the $CP$ violating phases in SUSY sector are not suppressed. The electric dipole moments of the neutron and the electron are large, but can be smaller than their experimental upper bounds if the scalar quarks and leptons are heavier than a few TeV. $T$ violating asymmetries in the production processes of the different neutralino pair and the different chargino pair emerge at the tree level. They could be as large as of order $10^{-2}$ in unpolarized electron beam experiments and $10^{-1}$ in polarized electron beam experiments. In a pair production of the charginos of the same mass, the asymmetry emerges through the electric and the weak "electric" dipole moments of the charginos at the loop level, but its magnitude is at most of order $10^{-4}$.
[ { "created": "Sat, 12 Mar 1994 10:18:02 GMT", "version": "v1" } ]
2015-06-25
[ [ "Kizukuri", "Yoshiki", "" ], [ "Oshimo", "Noriyuki", "" ] ]
$CP$ violating phenomena predicted by the minimal supersymmetric standard model are discussed in a case where the $CP$ violating phases in SUSY sector are not suppressed. The electric dipole moments of the neutron and the electron are large, but can be smaller than their experimental upper bounds if the scalar quarks and leptons are heavier than a few TeV. $T$ violating asymmetries in the production processes of the different neutralino pair and the different chargino pair emerge at the tree level. They could be as large as of order $10^{-2}$ in unpolarized electron beam experiments and $10^{-1}$ in polarized electron beam experiments. In a pair production of the charginos of the same mass, the asymmetry emerges through the electric and the weak "electric" dipole moments of the charginos at the loop level, but its magnitude is at most of order $10^{-4}$.
2401.17559
Shile Chen
Shile Chen, Jiaxing Zhao, Pengfei Zhuang
Heavy flavor production under a strong magnetic field
null
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The magnetic field created in high energy nuclear collisions will affect the dynamical processes in the QCD medium, especially the heavy quark production that happens in the initial stage of the collisions. We calculate in a strong magnetic field the heavy quark production cross section for the elementary process gg {\rightarrow} Q{\bar Q} at leading order and the corresponding transverse momentum distribution in nucleus-nucleus collisions. In comparison to the QED process, the heavy quark production is dominated by the unique QCD channel with gluon self-interaction. Due to the dimension reduction of quark phase space in a strong magnetic field, the production is concentrated in a very narrow energy region above the threshold. Since the translation invariance is broken, the production becomes anisotropic in magnetic field.
[ { "created": "Wed, 31 Jan 2024 02:48:44 GMT", "version": "v1" } ]
2024-02-01
[ [ "Chen", "Shile", "" ], [ "Zhao", "Jiaxing", "" ], [ "Zhuang", "Pengfei", "" ] ]
The magnetic field created in high energy nuclear collisions will affect the dynamical processes in the QCD medium, especially the heavy quark production that happens in the initial stage of the collisions. We calculate in a strong magnetic field the heavy quark production cross section for the elementary process gg {\rightarrow} Q{\bar Q} at leading order and the corresponding transverse momentum distribution in nucleus-nucleus collisions. In comparison to the QED process, the heavy quark production is dominated by the unique QCD channel with gluon self-interaction. Due to the dimension reduction of quark phase space in a strong magnetic field, the production is concentrated in a very narrow energy region above the threshold. Since the translation invariance is broken, the production becomes anisotropic in magnetic field.
hep-ph/0211240
Chun-Khiang Chua
Chun-Khiang Chua and Wei-Shu Hou
Three-body Baryonic anti-B -->Lambda anti-p pi Decays and Such
18 pages, 3 figures; use updated Belle results, add Lambda polarization study
Eur.Phys.J.C29:27-35,2003
10.1140/epjc/s2003-01203-8
null
hep-ph
null
We study decay rates and spectra of anti-B --> Lambda anti-p pi, Sigma0 anti-p pi, Sigma- anti-n pi, Xi0 anti-Sigma+ pi, Xi- anti-Sigma0 pi and Xi- anti-Lambda pi modes under a factorization approach. The baryon pairs are produced through vector, axial vector, scalar and pseudoscalar operators. Previous predictions, including ours, are an order of magnitude too small compared to experiment. By incorporating QCD counting rules and studying the asymptotic behavior, we find an earlier relation between the pseudoscalar and axial vector form factors to be too restrictive. Instead, the pseudoscalar and scalar form factors are related asymptotically. Following this approach, the measured Lambda anti-p pi rate (~4.0x10^{-6}) and spectrum can be understood, and Lambda should be dominantly left-hand polarized, while we expect Br(Sigma0 anti-p pi)~1.6x10^{-6}. These results and other predictions can be checked soon.
[ { "created": "Fri, 15 Nov 2002 08:27:22 GMT", "version": "v1" }, { "created": "Mon, 24 Feb 2003 11:09:27 GMT", "version": "v2" } ]
2009-01-07
[ [ "Chua", "Chun-Khiang", "" ], [ "Hou", "Wei-Shu", "" ] ]
We study decay rates and spectra of anti-B --> Lambda anti-p pi, Sigma0 anti-p pi, Sigma- anti-n pi, Xi0 anti-Sigma+ pi, Xi- anti-Sigma0 pi and Xi- anti-Lambda pi modes under a factorization approach. The baryon pairs are produced through vector, axial vector, scalar and pseudoscalar operators. Previous predictions, including ours, are an order of magnitude too small compared to experiment. By incorporating QCD counting rules and studying the asymptotic behavior, we find an earlier relation between the pseudoscalar and axial vector form factors to be too restrictive. Instead, the pseudoscalar and scalar form factors are related asymptotically. Following this approach, the measured Lambda anti-p pi rate (~4.0x10^{-6}) and spectrum can be understood, and Lambda should be dominantly left-hand polarized, while we expect Br(Sigma0 anti-p pi)~1.6x10^{-6}. These results and other predictions can be checked soon.
hep-ph/9711346
Jean Letessier
Jean Letessier, Johann Rafelski, Ahmed Tounsi
Gluon production, cooling and entropy in nuclear collisions
Replaced for bad printing on US paper. 7 pages, LaTeX, 4 postscript figures
Phys.Rev.C50:406-409,1994
10.1103/PhysRevC.50.406
null
hep-ph nucl-th
null
We study the cooling (heating) of a glue-parton gas due to production (destruction) of particles and determine the associated production of entropy. We incorporate sharing of the system energy among a changing number of particles. We find that the entropy of an evolving glue-parton gas changes in an insignificant range once the initial high temperature state has been formed, despite a great change in particle number and temperature.
[ { "created": "Mon, 17 Nov 1997 11:31:43 GMT", "version": "v1" }, { "created": "Sat, 22 Nov 1997 17:59:39 GMT", "version": "v2" } ]
2008-11-26
[ [ "Letessier", "Jean", "" ], [ "Rafelski", "Johann", "" ], [ "Tounsi", "Ahmed", "" ] ]
We study the cooling (heating) of a glue-parton gas due to production (destruction) of particles and determine the associated production of entropy. We incorporate sharing of the system energy among a changing number of particles. We find that the entropy of an evolving glue-parton gas changes in an insignificant range once the initial high temperature state has been formed, despite a great change in particle number and temperature.
hep-ph/9608278
Dr Tony Williams
A.G. Williams, K. Kusaka and K.M. Simpson
Covariant Solutions of the Bethe-Salpeter Equation
6 pages of LaTeX, uses lprocl.sty and epsfig.sty with 3 figures. Talk presented at the workshop on Quantum Chromodynamics: Collision, Confinement, and Chaos, at the American University of Paris, France, June 1996, to appear in the conference proceedings. Entire manuscript available as a ps file at http://www.physics.adelaide.edu.au/theory/home.html or ftp://adelphi.adelaide.edu.au/pub/theory/ADP-96-26.T225.ps
null
null
ADP-96-26/T225
hep-ph
null
There is a need for covariant solutions of bound state equations in order to construct realistic QCD based models of mesons and baryons. Furthermore, we ideally need to know the structure of these bound states in all kinematical regimes, which makes a direct solution in Minkowski space (without any 3-dimensional reductions) desirable. The Bethe-Salpeter equation (BSE) for bound states in scalar theories is reformulated and solved for arbitrary scattering kernels in terms of a generalized spectral representation directly in Minkowski space (K. Kusaka et al., PRD 51, 7026 '95). This differs from the conventional Euclidean approach, where the BSE can only be solved in ladder approximation after a Wick rotation.
[ { "created": "Fri, 9 Aug 1996 05:55:17 GMT", "version": "v1" } ]
2007-05-23
[ [ "Williams", "A. G.", "" ], [ "Kusaka", "K.", "" ], [ "Simpson", "K. M.", "" ] ]
There is a need for covariant solutions of bound state equations in order to construct realistic QCD based models of mesons and baryons. Furthermore, we ideally need to know the structure of these bound states in all kinematical regimes, which makes a direct solution in Minkowski space (without any 3-dimensional reductions) desirable. The Bethe-Salpeter equation (BSE) for bound states in scalar theories is reformulated and solved for arbitrary scattering kernels in terms of a generalized spectral representation directly in Minkowski space (K. Kusaka et al., PRD 51, 7026 '95). This differs from the conventional Euclidean approach, where the BSE can only be solved in ladder approximation after a Wick rotation.
hep-ph/0312065
Danny Marfatia
V. Barger, Danny Marfatia, Adam Tregre
Neutrino mass limits from SDSS, 2dFGRS and WMAP
4 pages, 2 figures. Only unconstrained bias fit included. References added
Phys.Lett.B595:55-59,2004
10.1016/j.physletb.2004.06.049
BUHEP-03-21, MADPH-03-1363
hep-ph astro-ph hep-ex nucl-ex nucl-th
null
We investigate whether cosmological data suggest the need for massive neutrinos. We employ galaxy power spectrum measurements from the Sloan Digital Sky Survey (SDSS) and the Two Degree Field Galaxy Redshift Survey (2dFGRS), along with cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP) and 27 other CMB experiments. We also use the measurement of the Hubble parameter from the Hubble Space Telescope (HST) Key Project. We find the sum of the neutrino masses to be smaller than 0.75 eV at 2\sigma (1.1 eV at 3\sigma).
[ { "created": "Thu, 4 Dec 2003 18:26:53 GMT", "version": "v1" }, { "created": "Tue, 9 Dec 2003 20:35:36 GMT", "version": "v2" } ]
2008-11-26
[ [ "Barger", "V.", "" ], [ "Marfatia", "Danny", "" ], [ "Tregre", "Adam", "" ] ]
We investigate whether cosmological data suggest the need for massive neutrinos. We employ galaxy power spectrum measurements from the Sloan Digital Sky Survey (SDSS) and the Two Degree Field Galaxy Redshift Survey (2dFGRS), along with cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP) and 27 other CMB experiments. We also use the measurement of the Hubble parameter from the Hubble Space Telescope (HST) Key Project. We find the sum of the neutrino masses to be smaller than 0.75 eV at 2\sigma (1.1 eV at 3\sigma).
hep-ph/0105300
Christopher Kolda
Christopher Kolda and William Lahneman (University of Notre Dame)
Exponential Quintessence and the End of Acceleration
8 pages Latex; 3 figures
null
null
UND-HEP-01-K02
hep-ph astro-ph
null
Recent observations indicate that the universe's expansion has been accelerating of late. But recent theoretical work has highlighted the difficulty of squaring acceleration with the underlying assumptions of string theory, disfavoring most models of quintessence. because they predict eternal acceleration. We show that one of the simplest and most motivated quintessence models described by an exponential potential can produce the acceleration needed to explain the data while also predicting only a finite period of acceleration, consistent with theoretical paradigms. This model is no more tuned than the canonical tracking quintessence models.
[ { "created": "Tue, 29 May 2001 08:43:41 GMT", "version": "v1" }, { "created": "Tue, 31 Jul 2001 16:39:32 GMT", "version": "v2" } ]
2007-05-23
[ [ "Kolda", "Christopher", "", "University of Notre Dame" ], [ "Lahneman", "William", "", "University of Notre Dame" ] ]
Recent observations indicate that the universe's expansion has been accelerating of late. But recent theoretical work has highlighted the difficulty of squaring acceleration with the underlying assumptions of string theory, disfavoring most models of quintessence. because they predict eternal acceleration. We show that one of the simplest and most motivated quintessence models described by an exponential potential can produce the acceleration needed to explain the data while also predicting only a finite period of acceleration, consistent with theoretical paradigms. This model is no more tuned than the canonical tracking quintessence models.
hep-ph/0502217
Pedro Fernando Simoes Costa
Pedro Costa, M. C. Ruivo, C. A. de Sousa, Yu. L. Kalinovsky
Restoration of U$_A$(1) symmetry and meson spectrum in hot or dense matter
9 pages, 5 figures. Talk given at Joint Meeting Heidelberg-Liege-Paris-Rostock (HLPR 2004), Spa, Belgium, 16-18 Dec 2004
AIP Conf.Proc. 775 (2005) 173
10.1063/1.1961054
null
hep-ph
null
We explore the effects of breaking and restoration of chiral and axial symmetries using an extended three-flavor Nambu-Jona-Lasinio model that incorporates explicitly the axial anomaly through the 't Hooft interaction. We implement a temperature (density) dependence of the anomaly coefficient motivated by lattice results for the topological susceptibility. The spectrum of scalar and pseudoscalar mesons is analyzed bearing in mind the identification of chiral partners and the study of its convergence. We also concentrate on the behavior of the mixing angles that give us relevant information on the issue under discussion. The results suggest that the axial part of the symmetry is restored before the possible restoration of the full U(3)$\otimes$U(3) chiral symmetry might occur.
[ { "created": "Wed, 23 Feb 2005 14:21:04 GMT", "version": "v1" } ]
2007-05-23
[ [ "Costa", "Pedro", "" ], [ "Ruivo", "M. C.", "" ], [ "de Sousa", "C. A.", "" ], [ "Kalinovsky", "Yu. L.", "" ] ]
We explore the effects of breaking and restoration of chiral and axial symmetries using an extended three-flavor Nambu-Jona-Lasinio model that incorporates explicitly the axial anomaly through the 't Hooft interaction. We implement a temperature (density) dependence of the anomaly coefficient motivated by lattice results for the topological susceptibility. The spectrum of scalar and pseudoscalar mesons is analyzed bearing in mind the identification of chiral partners and the study of its convergence. We also concentrate on the behavior of the mixing angles that give us relevant information on the issue under discussion. The results suggest that the axial part of the symmetry is restored before the possible restoration of the full U(3)$\otimes$U(3) chiral symmetry might occur.
2205.07239
Eberhard Klempt
E. Klempt, A.V. Sarantsev, I. Denisenko, and K.V. Nikonov
Search for the tensor glueball
8 pages, 3 figures, 2 Tables
null
10.1016/j.physletb.2022.137171
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The tensor glueball is searched for in BESIII data on radiative $J/\psi$ decays into $\pi^0\pi^0$ and $K_sK_s$. The $\pi\pi$ invariant mass distribution exhibits an enhancement that can be described by a pole at $(2210\pm 60) -i(180\pm 60)$\,MeV. We speculate if the tensor glueball could be distributed among high-mass tensor mesons.
[ { "created": "Sun, 15 May 2022 09:49:10 GMT", "version": "v1" } ]
2022-06-01
[ [ "Klempt", "E.", "" ], [ "Sarantsev", "A. V.", "" ], [ "Denisenko", "I.", "" ], [ "Nikonov", "K. V.", "" ] ]
The tensor glueball is searched for in BESIII data on radiative $J/\psi$ decays into $\pi^0\pi^0$ and $K_sK_s$. The $\pi\pi$ invariant mass distribution exhibits an enhancement that can be described by a pole at $(2210\pm 60) -i(180\pm 60)$\,MeV. We speculate if the tensor glueball could be distributed among high-mass tensor mesons.
hep-ph/0105169
V. Dmitrasinovic
V. Dmitrasinovic
Discriminating between effective theories of U_{A}(1) symmetry breaking
6 pages, 1 eps file, Yonsei "Hadrons and Nuclei" conference proceedings
null
10.1063/1.1425488
null
hep-ph
null
We address the question if one can empirically distinguish between the two proposed solutions to the ``$U_A (1)$ problem'': the 't Hooft, and the Veneziano-Witten $U_{A}(1)$ symmetry breaking effective interactions. Two hadronic observables are offered as discriminants: (1) The scalar ($0^{+}$) meson spectrum; (2) Weinberg's second spectral sum rule. Their present experimental status is discussed.
[ { "created": "Thu, 17 May 2001 06:38:22 GMT", "version": "v1" } ]
2009-11-07
[ [ "Dmitrasinovic", "V.", "" ] ]
We address the question if one can empirically distinguish between the two proposed solutions to the ``$U_A (1)$ problem'': the 't Hooft, and the Veneziano-Witten $U_{A}(1)$ symmetry breaking effective interactions. Two hadronic observables are offered as discriminants: (1) The scalar ($0^{+}$) meson spectrum; (2) Weinberg's second spectral sum rule. Their present experimental status is discussed.
1910.01703
Marek Tasevsky
M. Tasevsky, L. A. Harland-Lang, V. A. Khoze, M. G. Ryskin
Searches for Dark Matter at the LHC in forward proton mode
6 pages, EPS-HEP 2019 Proceedings. Corrected the conference name only
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze in detail the LHC prospects at the center-of-mass energy of 14 TeV for charged electroweakino searches, decaying to leptons, in compressed supersymmetry scenarios, via exclusive photon-initiated pair production. This provides a potentially increased sensitivity in comparison to inclusive channels, where the background is often overwhelming. We pay particular attention to the challenges that such searches would face in the hostile high pile-up environment of the LHC, giving close consideration to the backgrounds that will be present. The signal we focus on is the exclusive production of same-flavour muon and electron pairs, with missing energy in the final state, and with two outgoing intact protons registered by the dedicated forward proton detectors installed in association with ATLAS and CMS. We present results for slepton masses of 120--300 GeV and slepton-neutralino mass splitting of 10-20 GeV, and find that the relevant backgrounds can be controlled to the level of the expected signal yields. The most significant such backgrounds are due to semi-exclusive lepton pair production at lower masses, with a proton produced in the initial proton dissociation system registering in the forward detectors, and from the coincidence of forward protons produced in pile-up events with an inclusive central event that mimics the signal. We also outline a range of potential methods to further suppress these backgrounds as well as to enlarge the signal yields.
[ { "created": "Thu, 3 Oct 2019 19:48:24 GMT", "version": "v1" }, { "created": "Tue, 22 Oct 2019 05:51:10 GMT", "version": "v2" } ]
2019-10-23
[ [ "Tasevsky", "M.", "" ], [ "Harland-Lang", "L. A.", "" ], [ "Khoze", "V. A.", "" ], [ "Ryskin", "M. G.", "" ] ]
We analyze in detail the LHC prospects at the center-of-mass energy of 14 TeV for charged electroweakino searches, decaying to leptons, in compressed supersymmetry scenarios, via exclusive photon-initiated pair production. This provides a potentially increased sensitivity in comparison to inclusive channels, where the background is often overwhelming. We pay particular attention to the challenges that such searches would face in the hostile high pile-up environment of the LHC, giving close consideration to the backgrounds that will be present. The signal we focus on is the exclusive production of same-flavour muon and electron pairs, with missing energy in the final state, and with two outgoing intact protons registered by the dedicated forward proton detectors installed in association with ATLAS and CMS. We present results for slepton masses of 120--300 GeV and slepton-neutralino mass splitting of 10-20 GeV, and find that the relevant backgrounds can be controlled to the level of the expected signal yields. The most significant such backgrounds are due to semi-exclusive lepton pair production at lower masses, with a proton produced in the initial proton dissociation system registering in the forward detectors, and from the coincidence of forward protons produced in pile-up events with an inclusive central event that mimics the signal. We also outline a range of potential methods to further suppress these backgrounds as well as to enlarge the signal yields.
1611.07234
Bernard Pire
B. Pire, K. Semenov-Tian-Shansky and L. Szymanowski
Backward charmonium production in $\pi N$ collisions
15 pages, 5 figures. Substantially revised version. version 3 matches published version in Phys.Rev.D95, 034021
Phys. Rev. D 95, 034021 (2017)
10.1103/PhysRevD.95.034021
CPHT-RR050.112016
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The QCD collinear factorization framework allows to describe exclusive backward production of a $J/\psi$ meson in pion-nucleon collisions in terms of pion-to-nucleon transition distribution amplitudes. We calculate the scattering amplitude at the leading order in the strong coupling constant and estimate the cross section of this reaction in the backward kinematical region for a medium energy pion beam available at the J-Parc experimental facility.
[ { "created": "Tue, 22 Nov 2016 10:18:48 GMT", "version": "v1" }, { "created": "Wed, 23 Nov 2016 16:45:43 GMT", "version": "v2" }, { "created": "Mon, 20 Feb 2017 10:48:32 GMT", "version": "v3" } ]
2017-02-22
[ [ "Pire", "B.", "" ], [ "Semenov-Tian-Shansky", "K.", "" ], [ "Szymanowski", "L.", "" ] ]
The QCD collinear factorization framework allows to describe exclusive backward production of a $J/\psi$ meson in pion-nucleon collisions in terms of pion-to-nucleon transition distribution amplitudes. We calculate the scattering amplitude at the leading order in the strong coupling constant and estimate the cross section of this reaction in the backward kinematical region for a medium energy pion beam available at the J-Parc experimental facility.
1502.01727
Chakrit Pongkitivanichkul
Bobby S. Acharya, Krzysztof Bo\.zek, Miguel Crispim Rom\~ao, Stephen F. King, Chakrit Pongkitivanichkul
SO(10) Grand Unification in M theory on a G2 manifold
5 pages, added references, revised argument on equation 18, results unchanged, a new example is given in equation 24, agrees with published version in Physical Review D
Phys. Rev. D 92, 055011 (2015)
10.1103/PhysRevD.92.055011
KCL-PH-TH/2015-04
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider Grand Unified Theories based on $SO(10)$ which originate from string/$M$ theory on $G_2$ manifolds or Calabi-Yau spaces with discrete symmetries. In this framework we are naturally led to a novel solution of the doublet-triplet splitting problem previously considered by Dvali which involves an extra vector-like Standard Model family and light, but weakly coupled colour triplets. These additional states are predicted to be accessible at the LHC and also induce R-parity violation. Gauge coupling unification occurs with a larger GUT coupling.
[ { "created": "Thu, 5 Feb 2015 21:08:32 GMT", "version": "v1" }, { "created": "Mon, 7 Dec 2015 15:35:11 GMT", "version": "v2" } ]
2016-08-07
[ [ "Acharya", "Bobby S.", "" ], [ "Bożek", "Krzysztof", "" ], [ "Romão", "Miguel Crispim", "" ], [ "King", "Stephen F.", "" ], [ "Pongkitivanichkul", "Chakrit", "" ] ]
We consider Grand Unified Theories based on $SO(10)$ which originate from string/$M$ theory on $G_2$ manifolds or Calabi-Yau spaces with discrete symmetries. In this framework we are naturally led to a novel solution of the doublet-triplet splitting problem previously considered by Dvali which involves an extra vector-like Standard Model family and light, but weakly coupled colour triplets. These additional states are predicted to be accessible at the LHC and also induce R-parity violation. Gauge coupling unification occurs with a larger GUT coupling.
hep-ph/9307257
null
Tadashi Kon
Polarization Effects in Scalar Lepton Production at High Energy $\gamma\gamma$ Colliders
6 pages (LaTeX), 4 figures not included (available on request) ; ITP-SU-93/04
Phys.Lett. B316 (1993) 181-187
10.1016/0370-2693(93)90677-A
null
hep-ph
null
We investigate the charged scalar lepton production processes $\gamma\gamma\to{\widetilde{\ell}}^{+}{\widetilde{\ell}}^{-}$ at high energy $\gamma\gamma$ colliders in the framework of the minimal supersymmetric standard model (MSSM). Here the high energy $\gamma$ beams are obtained by the backward Compton scattering of the laser flush by the electron in the basic linear TeV $ee$ colliders. We consider the polarization of the laser photons as well as the electron beams. Appropriate beam polarization could be effective to enhance the cross section and to extract the signal from the dominant background $\gamma\gamma\to W^{+}W^{-}$.
[ { "created": "Tue, 13 Jul 1993 13:28:42 GMT", "version": "v1" } ]
2009-10-22
[ [ "Kon", "Tadashi", "" ] ]
We investigate the charged scalar lepton production processes $\gamma\gamma\to{\widetilde{\ell}}^{+}{\widetilde{\ell}}^{-}$ at high energy $\gamma\gamma$ colliders in the framework of the minimal supersymmetric standard model (MSSM). Here the high energy $\gamma$ beams are obtained by the backward Compton scattering of the laser flush by the electron in the basic linear TeV $ee$ colliders. We consider the polarization of the laser photons as well as the electron beams. Appropriate beam polarization could be effective to enhance the cross section and to extract the signal from the dominant background $\gamma\gamma\to W^{+}W^{-}$.
hep-ph/9811240
Martti Raidal
Ernest Ma, Martti Raidal, Utpal Sarkar
Baryogenesis with Scalar Bilinears
LATEX, 14 pages, one figure included
Phys.Rev. D60 (1999) 076005
10.1103/PhysRevD.60.076005
DESY 98-167, UCRHEP-T239
hep-ph
null
We show that if a baryon asymmetry of the universe is generated through the out-of-equilibrium decays of heavy scalar bilinears coupling to two fermions of the minimal standard model, it is necessarily an asymmetry conserving $(B-L)$ which cannot survive past the electroweak phase transition because of sphalerons. We then show that a surviving $(B-L)$ asymmetry may be generated if the heavy scalars decay into two fermions, \underline {and into two light scalars} (which may be detectable at hadron colliders). We list all possible such trilinear scalar interactions, and discuss how our new baryogenesis scenario may occur naturally in supersymmetric grand unified theories.
[ { "created": "Wed, 4 Nov 1998 13:38:29 GMT", "version": "v1" } ]
2009-10-31
[ [ "Ma", "Ernest", "" ], [ "Raidal", "Martti", "" ], [ "Sarkar", "Utpal", "" ] ]
We show that if a baryon asymmetry of the universe is generated through the out-of-equilibrium decays of heavy scalar bilinears coupling to two fermions of the minimal standard model, it is necessarily an asymmetry conserving $(B-L)$ which cannot survive past the electroweak phase transition because of sphalerons. We then show that a surviving $(B-L)$ asymmetry may be generated if the heavy scalars decay into two fermions, \underline {and into two light scalars} (which may be detectable at hadron colliders). We list all possible such trilinear scalar interactions, and discuss how our new baryogenesis scenario may occur naturally in supersymmetric grand unified theories.
1508.05616
Hiroaki Sugiyama
Shinya Kanemura, Tetsuo Shindou, Hiroaki Sugiyama
R-Parity Conserving Supersymmetric Extension of the Zee Model
19 pages, 4 eps files, published in PRD
Phys.Rev.D92 : 115001, 2015
10.1103/PhysRevD.92.115001
UT-HET 104, KU-PH-018
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend the Zee model, where tiny neutrino masses are generated at the one loop level, to a supersymmetric model with R-parity conservation. It is found that the neutrino mass matrix can be consistent with the neutrino oscillation data thanks to the nonholomorphic Yukawa interaction generated via one-loop diagrams of sleptons. We find a parameter set of the model, where in addition to the neutrino oscillation data, experimental constraints from the lepton flavor violating decays of charged leptons and current LHC data are also satisfied. In the parameter set, an additional CP-even neutral Higgs boson other than the standard-model-like one, a CP-odd neutral Higgs boson, and two charged scalar bosons are light enough to be produced at the LHC and future lepton colliders. If the lightest charged scalar bosons are mainly composed of the SU(2)_L-singlet scalar boson in the model, they would decay into e nu and mu nu with 50% of a branching ratio for each. In such a case, the relation among the masses of the charged scalar bosons and the CP-odd Higgs in the minimal supersymmetric standard model approximately holds with a radiative correction. Our model can be tested by measuring the specific decay patterns of charged scalar bosons and the discriminative mass spectrum of additional scalar bosons.
[ { "created": "Sun, 23 Aug 2015 15:03:24 GMT", "version": "v1" }, { "created": "Wed, 9 Dec 2015 15:36:33 GMT", "version": "v2" } ]
2015-12-10
[ [ "Kanemura", "Shinya", "" ], [ "Shindou", "Tetsuo", "" ], [ "Sugiyama", "Hiroaki", "" ] ]
We extend the Zee model, where tiny neutrino masses are generated at the one loop level, to a supersymmetric model with R-parity conservation. It is found that the neutrino mass matrix can be consistent with the neutrino oscillation data thanks to the nonholomorphic Yukawa interaction generated via one-loop diagrams of sleptons. We find a parameter set of the model, where in addition to the neutrino oscillation data, experimental constraints from the lepton flavor violating decays of charged leptons and current LHC data are also satisfied. In the parameter set, an additional CP-even neutral Higgs boson other than the standard-model-like one, a CP-odd neutral Higgs boson, and two charged scalar bosons are light enough to be produced at the LHC and future lepton colliders. If the lightest charged scalar bosons are mainly composed of the SU(2)_L-singlet scalar boson in the model, they would decay into e nu and mu nu with 50% of a branching ratio for each. In such a case, the relation among the masses of the charged scalar bosons and the CP-odd Higgs in the minimal supersymmetric standard model approximately holds with a radiative correction. Our model can be tested by measuring the specific decay patterns of charged scalar bosons and the discriminative mass spectrum of additional scalar bosons.
hep-ph/0610393
Jean-Philippe Lansberg
J.P. Lansberg
Off-shell and non-static contributions to heavy-quarkonium production
Presented at the 7th International Conference on Quark Confinement and Hadron Spectrum (QCHS7), September 2-7 2006, Ponta Delgada, Portugal and at the 4th Meeting of the Quarkonium Working Group, June 27-30 2006, BNL, USA, 4 pages, 3 figures, LaTeX, uses aip-6s.clo, aipproc.cls and aipxfm.sty (included)
AIPConf.Proc.892:324-326,2007
10.1063/1.2714407
null
hep-ph
null
We have shown that if one relaxes the constraint that the quarks in a heavy quarkonium are at rest and on-shell, new contributions to the discontinuity of the production amplitude appear. These can be seen as a s-cut in the amplitude and are on the same footage as the classical cut of the Colour-Singlet Model (CSM), where the heavy quarks forming the quarkonium are put on-shell by hypothesis. We treat this cut in a gauge-invariant manner by introducing necessary new 4-point vertices, suggestive of the colour-octet mechanism. We have further shown that this cut contributes at least as much as the LO CSM at large P_T. However, the 4-point vertices cannot be totally constrained and an ambiguity remains to what concerns their actual contribution. Theoretical insights from meson photoproduction are discussed in that context.
[ { "created": "Sun, 29 Oct 2006 17:23:26 GMT", "version": "v1" } ]
2008-11-26
[ [ "Lansberg", "J. P.", "" ] ]
We have shown that if one relaxes the constraint that the quarks in a heavy quarkonium are at rest and on-shell, new contributions to the discontinuity of the production amplitude appear. These can be seen as a s-cut in the amplitude and are on the same footage as the classical cut of the Colour-Singlet Model (CSM), where the heavy quarks forming the quarkonium are put on-shell by hypothesis. We treat this cut in a gauge-invariant manner by introducing necessary new 4-point vertices, suggestive of the colour-octet mechanism. We have further shown that this cut contributes at least as much as the LO CSM at large P_T. However, the 4-point vertices cannot be totally constrained and an ambiguity remains to what concerns their actual contribution. Theoretical insights from meson photoproduction are discussed in that context.
1811.10891
Eugenio Megias
Eugenio Megias, Germano Nardini, Mariano Quiros
Gravitational waves and collider signatures from holographic phase transitions in soft walls
8 pages, 2 figures, 2 tables. Talk given by E.Megias at the XIIIth Conference on Quark Confinement and the Hadron Spectrum (Confinement 2018), 31 Jul - 6 Aug 2018, Maynooth, Ireland
null
null
UAB-FT-778
hep-ph gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using a five-dimensional warped model including a scalar potential with an exponential behavior in the infrared, and strong back-reaction over the metric, we study the electroweak phase transition, and explore parameter regions that were previously inaccessible. The model exhibits gravitational waves and predicts a stochastic gravitational wave background observable, both at the Laser Interferometer Space Antenna and at the Einstein Telescope. Moreover, concerning the collider signatures predictions, the radion evades current constraints but may show up in future LHC runs.
[ { "created": "Tue, 27 Nov 2018 09:33:07 GMT", "version": "v1" } ]
2018-11-28
[ [ "Megias", "Eugenio", "" ], [ "Nardini", "Germano", "" ], [ "Quiros", "Mariano", "" ] ]
Using a five-dimensional warped model including a scalar potential with an exponential behavior in the infrared, and strong back-reaction over the metric, we study the electroweak phase transition, and explore parameter regions that were previously inaccessible. The model exhibits gravitational waves and predicts a stochastic gravitational wave background observable, both at the Laser Interferometer Space Antenna and at the Einstein Telescope. Moreover, concerning the collider signatures predictions, the radion evades current constraints but may show up in future LHC runs.
hep-ph/9407384
Jose Ramon Pelaez
A.Dobado, J.R.Pelaez, M.Urdiales
The Applicability of the Equivalence Theorem in $\chi PT$
LaTeX, 17 pages, 4 Figures available on request,(Contributed paper to the $27th$ International Conference in High Energy Physics,Glasgow)
null
null
null
hep-ph
null
We have explicitely calculated the tree level elastic scattering cross sections of two longitudinal gauge bosons, up to four derivatives in the chiral expansion both with and without using the Equivalence Theorem (ET). The numerical results show the existence of new and severe restrictions in the ET energy applicability range, as it was stated in our recent derivation, which we also review here, of the precise ET version in the Chiral Lagrangian description of the Standard Model Symmetry Breaking Sector.
[ { "created": "Tue, 26 Jul 1994 20:30:27 GMT", "version": "v1" } ]
2019-08-17
[ [ "Dobado", "A.", "" ], [ "Pelaez", "J. R.", "" ], [ "Urdiales", "M.", "" ] ]
We have explicitely calculated the tree level elastic scattering cross sections of two longitudinal gauge bosons, up to four derivatives in the chiral expansion both with and without using the Equivalence Theorem (ET). The numerical results show the existence of new and severe restrictions in the ET energy applicability range, as it was stated in our recent derivation, which we also review here, of the precise ET version in the Chiral Lagrangian description of the Standard Model Symmetry Breaking Sector.
1901.00105
Tanmoy Modak
Wei-Shu Hou, Masaya Kohda, Tanmoy Modak
Top-Assisted Di-Higgs boson Production Motivated by Baryogenesis
matches with published version
Phys. Rev. D 99, 055046 (2019)
10.1103/PhysRevD.99.055046
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study top-assisted di-Higgs production via $cg \to tH \to thh$, where $h$ is the 125 GeV scalar boson, and $H$ is the $CP$-even heavy Higgs. The context is the two Higgs doublet model without a $Z_2$ symmetry, where the extra Yukawa coupling $\rho_{tc}$ generates $tH$ production, with the extra top Yukawa $\rho_{tt} \simeq 0$ to avoid $gg \to H$ constraints. We find that discovery is possible for $m_H$ around 300 GeV or so at the LHC, but would need finite $h$-$H$ mixing angle $\cos\gamma$ to allow for finite $\lambda_{Hhh}$ coupling, and $\rho_{tc}$ also needs to be not too small. A sizable $\rho_{tc}$ could drive electroweak baryogenesis, which further motivates the search.
[ { "created": "Tue, 1 Jan 2019 06:44:30 GMT", "version": "v1" }, { "created": "Mon, 1 Apr 2019 09:23:43 GMT", "version": "v2" } ]
2019-04-03
[ [ "Hou", "Wei-Shu", "" ], [ "Kohda", "Masaya", "" ], [ "Modak", "Tanmoy", "" ] ]
We study top-assisted di-Higgs production via $cg \to tH \to thh$, where $h$ is the 125 GeV scalar boson, and $H$ is the $CP$-even heavy Higgs. The context is the two Higgs doublet model without a $Z_2$ symmetry, where the extra Yukawa coupling $\rho_{tc}$ generates $tH$ production, with the extra top Yukawa $\rho_{tt} \simeq 0$ to avoid $gg \to H$ constraints. We find that discovery is possible for $m_H$ around 300 GeV or so at the LHC, but would need finite $h$-$H$ mixing angle $\cos\gamma$ to allow for finite $\lambda_{Hhh}$ coupling, and $\rho_{tc}$ also needs to be not too small. A sizable $\rho_{tc}$ could drive electroweak baryogenesis, which further motivates the search.
1904.00020
Junwu Huang
Anson Hook and Junwu Huang
Searches for other vacua I: bubbles in our universe
30 pages, 10 figures, 1 table
null
10.1007/JHEP08(2019)148
null
hep-ph astro-ph.HE hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss models in which vacua other than our own can be directly observed in the present universe. Models with density-dependent vacuum structure can give rise to `non-lethal'-vacua: vacua with lower energy-density than our vacuum, but only in regions with finite Standard Model densities. These models provide an explicit example of a bubble which is confined to a finite region of space and produces potentially detectable signatures, unlike standard Coleman tunneling events where bubbles expand at the speed of light and are never directly observable. We study the expansion and contraction of a confined bubble created after a core-collapse supernova, focusing on energy deposition that may be observable in the vicinity of a supernova remnant due to the formation and evolution of a confined bubble.
[ { "created": "Fri, 29 Mar 2019 18:00:05 GMT", "version": "v1" } ]
2019-10-02
[ [ "Hook", "Anson", "" ], [ "Huang", "Junwu", "" ] ]
We discuss models in which vacua other than our own can be directly observed in the present universe. Models with density-dependent vacuum structure can give rise to `non-lethal'-vacua: vacua with lower energy-density than our vacuum, but only in regions with finite Standard Model densities. These models provide an explicit example of a bubble which is confined to a finite region of space and produces potentially detectable signatures, unlike standard Coleman tunneling events where bubbles expand at the speed of light and are never directly observable. We study the expansion and contraction of a confined bubble created after a core-collapse supernova, focusing on energy deposition that may be observable in the vicinity of a supernova remnant due to the formation and evolution of a confined bubble.
1112.0003
Bartosz Fornal
Jonathan M. Arnold, Bartosz Fornal
Color octet scalars and high pT four-jet events at LHC
5 pages, 9 figures
Phys.Rev.D85:055020,2012
10.1103/PhysRevD.85.055020
CALT 68-2858
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the effect of color octet scalars on the high transverse momenta four-jet cross section at the LHC. We consider both weak singlet and doublet scalars, concentrating on the case of small couplings to quarks. We find that a relatively early discovery at the LHC is possible for a range of scalar masses.
[ { "created": "Wed, 30 Nov 2011 21:00:00 GMT", "version": "v1" } ]
2012-04-03
[ [ "Arnold", "Jonathan M.", "" ], [ "Fornal", "Bartosz", "" ] ]
We study the effect of color octet scalars on the high transverse momenta four-jet cross section at the LHC. We consider both weak singlet and doublet scalars, concentrating on the case of small couplings to quarks. We find that a relatively early discovery at the LHC is possible for a range of scalar masses.
hep-ph/0512101
Sebastian J\"ager
Martin Beneke and Sebastian Jager
Hard spectator-scattering in B -> pi pi decays at NNLO
4 pages, uses PoS.cls (included). Contribution to the proceedings of the International Europhysics Conference on High Energy Physics, July 21st - 27th, 2005, Lisboa, Portugal
null
null
PITHA 05/18
hep-ph
null
We compute the 1-loop (NNLO) corrections to hard spectator-scattering in tree-dominated hadronic B decays. Depending on the values of hadronic input parameters the corrections are shown to have a significant impact on the B -> pi pi branching fractions.
[ { "created": "Thu, 8 Dec 2005 17:35:33 GMT", "version": "v1" } ]
2007-05-23
[ [ "Beneke", "Martin", "" ], [ "Jager", "Sebastian", "" ] ]
We compute the 1-loop (NNLO) corrections to hard spectator-scattering in tree-dominated hadronic B decays. Depending on the values of hadronic input parameters the corrections are shown to have a significant impact on the B -> pi pi branching fractions.
hep-ph/9604256
Masahumi Simojyo
Noriyasu Ohtsubo and Masafumi Shimojo
SO(10) Models on $Z_6$\ Orbifold with Dual Wilson Line
5 pages, Latex
Prog.Theor.Phys. 96 (1996) 665-668
10.1143/PTP.96.665
Kanazawa-96-06
hep-ph
null
'Dual' is a promising key word in the particle physics at present. The string theory is dual in any sense. The observed sector and the hidden sector are dual on the 10-dim. $E_8\times E_8$ heterotic string. We find $Z_6$ orbifold models preserving the duality under a torus compactification and realizing $SO(10)$ SUSY GUT in the obserbed sector under a twist division.
[ { "created": "Sat, 6 Apr 1996 06:42:58 GMT", "version": "v1" } ]
2009-10-28
[ [ "Ohtsubo", "Noriyasu", "" ], [ "Shimojo", "Masafumi", "" ] ]
'Dual' is a promising key word in the particle physics at present. The string theory is dual in any sense. The observed sector and the hidden sector are dual on the 10-dim. $E_8\times E_8$ heterotic string. We find $Z_6$ orbifold models preserving the duality under a torus compactification and realizing $SO(10)$ SUSY GUT in the obserbed sector under a twist division.
1106.2968
Xiang Liu
Zhi-Feng Sun, Jun He, Xiang Liu, Zhi-Gang Luo and Shi-Lin Zhu
$Z_b(10610)^\pm$ and $Z_b(10650)^\pm$ as the $B^*\bar{B}$ and $B^*\bar{B}^{*}$ molecular states
11 pages, 6 tables
Phys.Rev.D84:054002,2011
10.1103/PhysRevD.84.054002
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the framework of the one-boson-exchange model, we have studied the interaction of the $B^*\bar{B}$ and $B^*\bar{B}^{*}$ system. After considering the S-wave and D-wave mixing, we notice that both $Z_b(10610)^\pm$ and $Z_b(10650)^\pm$ can be interpreted as the $B^*\bar{B}$ and $B^*\bar{B}^{*}$ molecular states quite naturally. Within the same framework, there also exist several molecular charmonia including X(3872) and several other molecular bottomonia, which are the partners of $Z_b(10610)$ and $Z_b(10650)$. The long-range one-pion-exchange force alone is strong enough to form these loosely bound molecular states, which ensures the numerical results quite model-independent and robust.
[ { "created": "Wed, 15 Jun 2011 13:23:58 GMT", "version": "v1" } ]
2011-09-02
[ [ "Sun", "Zhi-Feng", "" ], [ "He", "Jun", "" ], [ "Liu", "Xiang", "" ], [ "Luo", "Zhi-Gang", "" ], [ "Zhu", "Shi-Lin", "" ] ]
In the framework of the one-boson-exchange model, we have studied the interaction of the $B^*\bar{B}$ and $B^*\bar{B}^{*}$ system. After considering the S-wave and D-wave mixing, we notice that both $Z_b(10610)^\pm$ and $Z_b(10650)^\pm$ can be interpreted as the $B^*\bar{B}$ and $B^*\bar{B}^{*}$ molecular states quite naturally. Within the same framework, there also exist several molecular charmonia including X(3872) and several other molecular bottomonia, which are the partners of $Z_b(10610)$ and $Z_b(10650)$. The long-range one-pion-exchange force alone is strong enough to form these loosely bound molecular states, which ensures the numerical results quite model-independent and robust.
1410.5753
Peihong Gu
Pei-Hong Gu
A new leptogenesis scenario parametrized by Dirac neutrino mass matrix
8 pages, 3 figures. Basic idea and results are unchanged while model and demonstrations are improved
Phys. Rev. D 96, 075024 (2017)
10.1103/PhysRevD.96.075024
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In an $SU(3)_{c}\times SU(2)_{L}\times SU(2)_{R}\times U(1)_{B-L}$ left-right symmetric framework, we present a new leptogenesis scenario parametrized by Dirac neutrino mass matrix. Benefited from the parity symmetry motivated to solve the strong CP problem, the dimensionless couplings of the mirror fields are identified to those of the ordinary fields. In particular, the mirror Dirac neutrinos have a heavy mass matrix proportional to the light mass matrix of the ordinary Dirac neutrinos. Through the $SU(2)_R$ gauge interactions, the mirror neutrinos can decay to generate a lepton asymmetry in the mirror muons and an opposite lepton asymmetry in the mirror electrons. Before the $SU(2)_L$ sphaleron processes stop working, the mirror muons can efficiently decay into the ordinary right-handed leptons with a dark matter scalar and hence the mirror muon asymmetry can be partially converted to a desired baryon asymmetry.
[ { "created": "Tue, 21 Oct 2014 17:39:57 GMT", "version": "v1" }, { "created": "Mon, 15 May 2017 10:40:35 GMT", "version": "v2" } ]
2017-10-25
[ [ "Gu", "Pei-Hong", "" ] ]
In an $SU(3)_{c}\times SU(2)_{L}\times SU(2)_{R}\times U(1)_{B-L}$ left-right symmetric framework, we present a new leptogenesis scenario parametrized by Dirac neutrino mass matrix. Benefited from the parity symmetry motivated to solve the strong CP problem, the dimensionless couplings of the mirror fields are identified to those of the ordinary fields. In particular, the mirror Dirac neutrinos have a heavy mass matrix proportional to the light mass matrix of the ordinary Dirac neutrinos. Through the $SU(2)_R$ gauge interactions, the mirror neutrinos can decay to generate a lepton asymmetry in the mirror muons and an opposite lepton asymmetry in the mirror electrons. Before the $SU(2)_L$ sphaleron processes stop working, the mirror muons can efficiently decay into the ordinary right-handed leptons with a dark matter scalar and hence the mirror muon asymmetry can be partially converted to a desired baryon asymmetry.
hep-ph/0607274
Bipin singh Koranga
Bipin Singh koranga, Mohan Narayan and S Uma Sankar
Possible CPT Violation from Planck Scale Effects
10 pages, 4 figures
Fizika B18:219-226,2009
null
null
hep-ph
null
At present there is good agreement between the neutrino mass-squared difference determined from the solar neutrino data and the anti-neutrino mass-squared difference determined from the KamLAND reactor anti-neutrino experiment. However, the central values of the two cases differ from each other by about $10^{-5}$ eV$^2$. An improvement in the accuracy of both the solar neutrino experiments and reactor anti-neutrino experiments can establish the existence of a non-zero difference between neutrino and anti-neutrino mass-squared differences and provide a signal for CPT violation. In this paper, we show how such a difference can arise through the CPT violating neutrino mass terms from Planck scale physics.
[ { "created": "Tue, 25 Jul 2006 15:20:49 GMT", "version": "v1" }, { "created": "Wed, 30 Aug 2006 13:51:05 GMT", "version": "v2" } ]
2009-12-11
[ [ "koranga", "Bipin Singh", "" ], [ "Narayan", "Mohan", "" ], [ "Sankar", "S Uma", "" ] ]
At present there is good agreement between the neutrino mass-squared difference determined from the solar neutrino data and the anti-neutrino mass-squared difference determined from the KamLAND reactor anti-neutrino experiment. However, the central values of the two cases differ from each other by about $10^{-5}$ eV$^2$. An improvement in the accuracy of both the solar neutrino experiments and reactor anti-neutrino experiments can establish the existence of a non-zero difference between neutrino and anti-neutrino mass-squared differences and provide a signal for CPT violation. In this paper, we show how such a difference can arise through the CPT violating neutrino mass terms from Planck scale physics.
2108.04066
Dr. Rukmani Mohanta
Mitesh Kumar Behera, Papia Panda, Priya Mishra, Shivaramakrishna Singirala, Rukmani Mohanta
Exploring Neutrino Masses and Mixing in the Seesaw Model with ${L_e-L_j}$ Gauged Symmetry
23 pages, 11 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we consider the implementation of $U(1)_{L_e-L_j}$ gauge symmetry, where $(j= \mu, \tau)$, to study the neutrino phenomenology within the framework of type-(I+II) seesaw. The model involves three right-handed neutrinos along with a scalar triplet in addition to the standard model particle spectrum. With the assigned charges under new $U(1)$, the neutrino mass matrix is found to acquire a two-zero texture and thus, turns out to be quite helpful in explaining the neutrino oscillation parameters and also accommodating the effective electron neutrino mass ($m_{ee}$) in neutrinoless double beta decay. We also briefly discuss the lepton flavor violating decays: $\mu\to e\gamma$, $\tau \to e \gamma$ and $\tau \to \mu \bar \mu \mu$. Finally, we shed light on the recent measurement of muon $g-2$.
[ { "created": "Mon, 9 Aug 2021 14:17:44 GMT", "version": "v1" }, { "created": "Sat, 6 Nov 2021 11:10:54 GMT", "version": "v2" } ]
2021-11-09
[ [ "Behera", "Mitesh Kumar", "" ], [ "Panda", "Papia", "" ], [ "Mishra", "Priya", "" ], [ "Singirala", "Shivaramakrishna", "" ], [ "Mohanta", "Rukmani", "" ] ]
In this work, we consider the implementation of $U(1)_{L_e-L_j}$ gauge symmetry, where $(j= \mu, \tau)$, to study the neutrino phenomenology within the framework of type-(I+II) seesaw. The model involves three right-handed neutrinos along with a scalar triplet in addition to the standard model particle spectrum. With the assigned charges under new $U(1)$, the neutrino mass matrix is found to acquire a two-zero texture and thus, turns out to be quite helpful in explaining the neutrino oscillation parameters and also accommodating the effective electron neutrino mass ($m_{ee}$) in neutrinoless double beta decay. We also briefly discuss the lepton flavor violating decays: $\mu\to e\gamma$, $\tau \to e \gamma$ and $\tau \to \mu \bar \mu \mu$. Finally, we shed light on the recent measurement of muon $g-2$.
1711.10289
Zhen-Xing Zhao
Xiao-Hui Hu, Yue-Long Shen, Wei Wang and Zhen-Xing Zhao
Weak decays of doubly heavy baryons: "decay constants"
15 pages, 4 figures, 4 tables, to be published in Chinese Physics C
Chin.Phys. C42 (2018) no.12, 123102
10.1088/1674-1137/42/12/123102
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inspired by the recent observation of the $\Xi_{cc}^{++}$ by LHCb collaboration, we explore the "decay constants" of doubly heavy baryons in the framework of QCD sum rules. With the $\Xi_{cc}, \Xi_{bc}, \Xi_{bb}$, and $\Omega_{cc}, \Omega_{bc}, \Omega_{bb}$ baryons interpolated by three-quark operators, we calculate the correlation functions using the operator product expansion and include the contribution from operators up to dimension six. On the hadron side, we consider both contributions from the lowest-lying states with $J^P=1/2^+$ and from negative parity baryons with $J^P=1/2^-$. We find that the results are stable and the contaminations from negative parity baryons are not severe. These results are ingredients for the QCD study of weak decays and other properties of doubly-heavy baryons.
[ { "created": "Tue, 28 Nov 2017 13:45:12 GMT", "version": "v1" }, { "created": "Thu, 23 Aug 2018 04:33:38 GMT", "version": "v2" } ]
2018-11-26
[ [ "Hu", "Xiao-Hui", "" ], [ "Shen", "Yue-Long", "" ], [ "Wang", "Wei", "" ], [ "Zhao", "Zhen-Xing", "" ] ]
Inspired by the recent observation of the $\Xi_{cc}^{++}$ by LHCb collaboration, we explore the "decay constants" of doubly heavy baryons in the framework of QCD sum rules. With the $\Xi_{cc}, \Xi_{bc}, \Xi_{bb}$, and $\Omega_{cc}, \Omega_{bc}, \Omega_{bb}$ baryons interpolated by three-quark operators, we calculate the correlation functions using the operator product expansion and include the contribution from operators up to dimension six. On the hadron side, we consider both contributions from the lowest-lying states with $J^P=1/2^+$ and from negative parity baryons with $J^P=1/2^-$. We find that the results are stable and the contaminations from negative parity baryons are not severe. These results are ingredients for the QCD study of weak decays and other properties of doubly-heavy baryons.
2302.02700
Pierluca Carenza
Pierluca Carenza, M. C. David Marsh
On the applicability of the Landau-Zener formula to axion-photon conversion
v2: 19 pages, 5 figures. minor changes to match the published version
JCAP04(2023)021
10.1088/1475-7516/2023/04/021
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Axions and photons resonantly interconvert in regions where the plasma frequency approximately equals the axion mass. This process is directly analogous to an avoided level crossing in quantum mechanics, for which the celebrated Landau-Zener (LZ) formula provides a simple, non-perturbative solution for the conversion probability. The LZ formula is commonly used in studies of axion-photon conversion; however, in this context, it relies on the assumption that the magnetic field variation is small compared to variations of the plasma frequency, which is frequently not the case in real plasmas. We derive a generalised version of the LZ formula by allowing the boundaries to be located at a scale that is similar to the inhomogeneities. We find that the LZ formula fails when the oscillation range is small compared to the resonance region. This failure is more severe in the adiabatic limit, when the plasma frequency varies slowly, resulting in a conversion probability that is not maximal as opposed to a naive application of the LZ formula. Moreover, we consider circumstances where the generalised LZ formula does not apply and present an alternative semi-classical approximation with complementary regime of validity.
[ { "created": "Mon, 6 Feb 2023 10:56:12 GMT", "version": "v1" }, { "created": "Thu, 13 Apr 2023 07:18:10 GMT", "version": "v2" } ]
2023-04-14
[ [ "Carenza", "Pierluca", "" ], [ "Marsh", "M. C. David", "" ] ]
Axions and photons resonantly interconvert in regions where the plasma frequency approximately equals the axion mass. This process is directly analogous to an avoided level crossing in quantum mechanics, for which the celebrated Landau-Zener (LZ) formula provides a simple, non-perturbative solution for the conversion probability. The LZ formula is commonly used in studies of axion-photon conversion; however, in this context, it relies on the assumption that the magnetic field variation is small compared to variations of the plasma frequency, which is frequently not the case in real plasmas. We derive a generalised version of the LZ formula by allowing the boundaries to be located at a scale that is similar to the inhomogeneities. We find that the LZ formula fails when the oscillation range is small compared to the resonance region. This failure is more severe in the adiabatic limit, when the plasma frequency varies slowly, resulting in a conversion probability that is not maximal as opposed to a naive application of the LZ formula. Moreover, we consider circumstances where the generalised LZ formula does not apply and present an alternative semi-classical approximation with complementary regime of validity.
1503.05836
Matti Heikinheimo
Sanjoy Biswas, Emidio Gabrielli, Matti Heikinheimo and Barbara Mele
Higgs-boson production in association with a Dark Photon in $e^+ e^-$ collisions
25 pages, 12 figures; Conclusion Section expandend, to appear in JHEP; v5: typographical errors corrected
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the production of a Higgs boson recoiling from a massless invisible system in $e^ + e^ -$ collisions. This is a quite distinctive signature that can arise when the Higgs boson is produced in association with a massless dark photon, which can happen in BSM scenarios foreseeing an extra unbroken $U(1)$ gauge group. Dark photons can indeed acquire effective couplings to the Higgs boson as occurs in models recently proposed to generate exponentially-spread Yukawa couplings. We analyze the signal and corresponding backgrounds for $H\to b\bar{b}$, and estimate ILC and FCC-ee sensitivities in a model-independent way.
[ { "created": "Thu, 19 Mar 2015 16:43:13 GMT", "version": "v1" }, { "created": "Wed, 25 Mar 2015 19:16:01 GMT", "version": "v2" }, { "created": "Mon, 18 May 2015 11:17:57 GMT", "version": "v3" }, { "created": "Thu, 13 Aug 2015 11:43:31 GMT", "version": "v4" }, { "c...
2016-09-06
[ [ "Biswas", "Sanjoy", "" ], [ "Gabrielli", "Emidio", "" ], [ "Heikinheimo", "Matti", "" ], [ "Mele", "Barbara", "" ] ]
We study the production of a Higgs boson recoiling from a massless invisible system in $e^ + e^ -$ collisions. This is a quite distinctive signature that can arise when the Higgs boson is produced in association with a massless dark photon, which can happen in BSM scenarios foreseeing an extra unbroken $U(1)$ gauge group. Dark photons can indeed acquire effective couplings to the Higgs boson as occurs in models recently proposed to generate exponentially-spread Yukawa couplings. We analyze the signal and corresponding backgrounds for $H\to b\bar{b}$, and estimate ILC and FCC-ee sensitivities in a model-independent way.
1402.5579
Takaaki Nomura
Cheng-Wei Chiang, Takaaki Nomura, Kei Yagyu
Phenomenology of $E_6$-Inspired Leptophobic $Z'$ Boson at the LHC
21 pages, 17 figures, 4 tables, version to appear in JHEP
null
10.1007/JHEP05(2014)106
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study collider phenomenology of a leptophobic $Z'$ boson existing in eight scenarios of the $E_6$ grand unified theory, differing in particle embeddings. We first review the current bound on the $Z'$ mass $m_{Z'}$ based upon the LHC data of $pp\to t\bar{t}$ process at 8 TeV collisions with an integrated luminosity of 19.6 fb$^{-1}$. Most scenarios have a lower bound of about 1 TeV. However, this constraint does not apply to the case where $m_{Z'} < 2 m_t$, and other methods need to be employed for this lower mass regime. Using existing UA2 constraints and dijet data at the LHC, we find that only one of the eight scenarios is excluded at 95\% confidence level. No bound can be obtained from $Wjj$ and $Zjj$ measurements. We propose to use the photon associated production of the $Z'$ boson that subsequently decays into a pair of bottom quarks, $pp\to Z'\gamma \to b\bar{b}\gamma$, at the LHC to explore the constraints in the lower mass regime. We compute the expected signal significance as a function of $m_{Z'}$ using detailed simulations of signal and irreducible background events. We find constraints for two more scenarios using the 8-TeV data and taking appropriate kinematical cuts. We also show the discovery reach for each scenario at the 14-TeV LHC machine.
[ { "created": "Sun, 23 Feb 2014 06:16:42 GMT", "version": "v1" }, { "created": "Wed, 5 Mar 2014 11:41:55 GMT", "version": "v2" }, { "created": "Wed, 21 May 2014 15:52:04 GMT", "version": "v3" } ]
2015-06-18
[ [ "Chiang", "Cheng-Wei", "" ], [ "Nomura", "Takaaki", "" ], [ "Yagyu", "Kei", "" ] ]
We study collider phenomenology of a leptophobic $Z'$ boson existing in eight scenarios of the $E_6$ grand unified theory, differing in particle embeddings. We first review the current bound on the $Z'$ mass $m_{Z'}$ based upon the LHC data of $pp\to t\bar{t}$ process at 8 TeV collisions with an integrated luminosity of 19.6 fb$^{-1}$. Most scenarios have a lower bound of about 1 TeV. However, this constraint does not apply to the case where $m_{Z'} < 2 m_t$, and other methods need to be employed for this lower mass regime. Using existing UA2 constraints and dijet data at the LHC, we find that only one of the eight scenarios is excluded at 95\% confidence level. No bound can be obtained from $Wjj$ and $Zjj$ measurements. We propose to use the photon associated production of the $Z'$ boson that subsequently decays into a pair of bottom quarks, $pp\to Z'\gamma \to b\bar{b}\gamma$, at the LHC to explore the constraints in the lower mass regime. We compute the expected signal significance as a function of $m_{Z'}$ using detailed simulations of signal and irreducible background events. We find constraints for two more scenarios using the 8-TeV data and taking appropriate kinematical cuts. We also show the discovery reach for each scenario at the 14-TeV LHC machine.
1210.7890
Rohit Dhir
Rohit Dhir and C. S. Kim
Branching ratios of $B_c$ Meson Decaying to Vector and Axial-Vector Mesons
26 Pages, Version to appear in Phys. Rev. D(2013)
Phys Rev D 87, 034004 (2013)
10.1103/PhysRevD.87.034004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the weak decays of $B_c$ mesons in Cabibbo-Kobayashi-Maskawa favored and suppressed modes. We present a detailed analysis of the $B_c$ meson decaying to vector meson (V) and axial-vector meson (A) in the final state. We also give the form factors involving $B_c \to A$ transition in the Isgur-Scora-Grinstein-Wise II framework and consequently, predict the branching ratios of $B_c \to V A$ and $AA$ decays.
[ { "created": "Tue, 30 Oct 2012 02:45:30 GMT", "version": "v1" }, { "created": "Tue, 22 Jan 2013 10:01:26 GMT", "version": "v2" } ]
2013-02-20
[ [ "Dhir", "Rohit", "" ], [ "Kim", "C. S.", "" ] ]
We investigate the weak decays of $B_c$ mesons in Cabibbo-Kobayashi-Maskawa favored and suppressed modes. We present a detailed analysis of the $B_c$ meson decaying to vector meson (V) and axial-vector meson (A) in the final state. We also give the form factors involving $B_c \to A$ transition in the Isgur-Scora-Grinstein-Wise II framework and consequently, predict the branching ratios of $B_c \to V A$ and $AA$ decays.
2107.11362
Derek Everett
Derek Everett
Quantifying the Quark Gluon Plasma
Ph.D. Thesis
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study of heavy-ion collisions presents a challenge to both theoretical and experimental nuclear physics. Due to the extremely short lifetime and small size of the collision system, disentangling information provided by experimental observables and progress in physical insight requires the careful application of plausible reasoning. I apply a program of statistical methodologies, primarily Bayesian, to quantify properties of the medium in specific models, as well as compare and criticize differing models of the system. Of particular interest are estimations of the specific shear and bulk viscosities, where we find that information carried by the experimental data is still limited. In particular we find a large sensitivity to prior assumptions at high temperatures. Moreover, sensitivities to model assumptions are present at low temperatures, and this source of model uncertainty is propagated with model averaging and model mixing.
[ { "created": "Fri, 23 Jul 2021 17:29:11 GMT", "version": "v1" }, { "created": "Wed, 25 Aug 2021 21:42:40 GMT", "version": "v2" } ]
2021-08-27
[ [ "Everett", "Derek", "" ] ]
The study of heavy-ion collisions presents a challenge to both theoretical and experimental nuclear physics. Due to the extremely short lifetime and small size of the collision system, disentangling information provided by experimental observables and progress in physical insight requires the careful application of plausible reasoning. I apply a program of statistical methodologies, primarily Bayesian, to quantify properties of the medium in specific models, as well as compare and criticize differing models of the system. Of particular interest are estimations of the specific shear and bulk viscosities, where we find that information carried by the experimental data is still limited. In particular we find a large sensitivity to prior assumptions at high temperatures. Moreover, sensitivities to model assumptions are present at low temperatures, and this source of model uncertainty is propagated with model averaging and model mixing.
1212.4155
Noburo Shiba
Noburo Shiba
Superluminal Propagation Caused by Radiative Corrections in a Uniform Electromagnetic Field
10 pages, 3 figures
null
null
OU-HET 774/2012
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the effect of radiative corrections on the maximum velocity of propagation of neutral scalar fields in a uniform electromagnetic field. The propagator of neutral scalar fields interacting with charged fields depends on the electromagnetic field through charged particle loops. The kinetic terms of the scalar fields are corrected and the maximum velocity of the scalar particle becomes greater or less than unity. We show that the maximum velocity becomes greater than unity in a simple example, a neutral scalar field coupled with two charged Dirac fields by Yukawa interaction. The maximum velocity depends on the frame of reference and causality is not violated. We discuss the possibility of this superluminal propagation in the Standard Model.
[ { "created": "Mon, 17 Dec 2012 21:00:07 GMT", "version": "v1" } ]
2013-01-07
[ [ "Shiba", "Noburo", "" ] ]
We consider the effect of radiative corrections on the maximum velocity of propagation of neutral scalar fields in a uniform electromagnetic field. The propagator of neutral scalar fields interacting with charged fields depends on the electromagnetic field through charged particle loops. The kinetic terms of the scalar fields are corrected and the maximum velocity of the scalar particle becomes greater or less than unity. We show that the maximum velocity becomes greater than unity in a simple example, a neutral scalar field coupled with two charged Dirac fields by Yukawa interaction. The maximum velocity depends on the frame of reference and causality is not violated. We discuss the possibility of this superluminal propagation in the Standard Model.
1201.3402
Kingman Cheung
Kingman Cheung, Po-Yan Tseng, Yue-Lin S. Tsai, and Tzu-Chiang Yuan
Global Constraints on Effective Dark Matter Interactions: Relic Density, Direct Detection, Indirect Detection, and Collider
39 pages, 10 figures; a number of references added; a new section about applicable models is added in the appendix; treatment of data sets are modified; comments on LEP monophoton, FERMI-LAT dSphs data, and other discussion. arXiv admin note: substantial text overlap with arXiv:1104.5329
null
10.1088/1475-7516/2012/05/001
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An effective interaction approach is used to describe the interactions between the spin 0 or spin 1/2 dark matter particle and the degrees of freedom of the standard model. This approach is applicable to those models in which the dark matter particles do not experience the standard-model interactions, e.g., hidden-sector models. We explore the effects of these effective interaction operators on (i) dark matter relic density, (ii) spin-independent and spin-dependent dark matter-nucleon scattering cross sections, (iii) cosmic antiproton and gamma ray fluxes from the galactic halo due to dark matter annihilation, and (iv) monojet and monophoton production plus missing energy at the Tevatron and the Large Hadron Collider (LHC). We combine the experimental data of relic density from WMAP7, spin-independent cross section from XENON100, spin-dependent cross section from XENON10, ZEPLIN-III, and SIMPLE, cosmic antiproton flux from PAMELA, cosmic gamma-ray flux from ${\it Fermi}$-LAT, and the monojet and monophoton data from the Tevatron and the LHC, to put the most comprehensive limits on each effective operator.
[ { "created": "Tue, 17 Jan 2012 00:18:29 GMT", "version": "v1" }, { "created": "Thu, 2 Feb 2012 10:24:00 GMT", "version": "v2" }, { "created": "Wed, 11 Apr 2012 03:38:44 GMT", "version": "v3" } ]
2015-06-03
[ [ "Cheung", "Kingman", "" ], [ "Tseng", "Po-Yan", "" ], [ "Tsai", "Yue-Lin S.", "" ], [ "Yuan", "Tzu-Chiang", "" ] ]
An effective interaction approach is used to describe the interactions between the spin 0 or spin 1/2 dark matter particle and the degrees of freedom of the standard model. This approach is applicable to those models in which the dark matter particles do not experience the standard-model interactions, e.g., hidden-sector models. We explore the effects of these effective interaction operators on (i) dark matter relic density, (ii) spin-independent and spin-dependent dark matter-nucleon scattering cross sections, (iii) cosmic antiproton and gamma ray fluxes from the galactic halo due to dark matter annihilation, and (iv) monojet and monophoton production plus missing energy at the Tevatron and the Large Hadron Collider (LHC). We combine the experimental data of relic density from WMAP7, spin-independent cross section from XENON100, spin-dependent cross section from XENON10, ZEPLIN-III, and SIMPLE, cosmic antiproton flux from PAMELA, cosmic gamma-ray flux from ${\it Fermi}$-LAT, and the monojet and monophoton data from the Tevatron and the LHC, to put the most comprehensive limits on each effective operator.
1107.3805
Gauthier Durieux
Zhe Dong, Gauthier Durieux, Jean-Marc Gerard, Tao Han, Fabio Maltoni
Baryon number violation at the LHC: the top option
5 pages, 3 figures, v2 matches the published version, with an extra sign corrected on the first line of eq.(6)
PhysRev D85 (2012) 016006
10.1103/PhysRevD.85.016006
CP3-11-24, MADPH-11-1573
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Subject to strong experimental constraints at low energies, baryon number violation is nonetheless well motivated from a theoretical point of view. We examine the possibility of observing baryon-number-violating top-quark production or decay at hadron colliders. We adopt a model independent effective approach and focus on operators with minimal mass-dimension. Corresponding effective coefficients could be directly probed at the Large Hadron Collider (LHC) already with an integrated luminosity of 1 inverse femtobarn at 7 TeV, and further constrained with 30 (100) inverse femtobarns at 7 (14) TeV.
[ { "created": "Tue, 19 Jul 2011 19:07:22 GMT", "version": "v1" }, { "created": "Fri, 21 Jan 2022 21:30:10 GMT", "version": "v2" } ]
2022-01-25
[ [ "Dong", "Zhe", "" ], [ "Durieux", "Gauthier", "" ], [ "Gerard", "Jean-Marc", "" ], [ "Han", "Tao", "" ], [ "Maltoni", "Fabio", "" ] ]
Subject to strong experimental constraints at low energies, baryon number violation is nonetheless well motivated from a theoretical point of view. We examine the possibility of observing baryon-number-violating top-quark production or decay at hadron colliders. We adopt a model independent effective approach and focus on operators with minimal mass-dimension. Corresponding effective coefficients could be directly probed at the Large Hadron Collider (LHC) already with an integrated luminosity of 1 inverse femtobarn at 7 TeV, and further constrained with 30 (100) inverse femtobarns at 7 (14) TeV.
hep-ph/0503277
Torleif E. O. Ericson
T. E. O. Ericson (1), A. N. Ivanov (2 and 3) ((1) Cern, Geneva, Switzerland (2) SMI and Technical University, Wien, Austria, (3) Polytechnic University, St. Petersburg, Russia)
Isospin breaking in pion-nucleon scattering at threshold by radiative processes
9 pages with 1 figure
null
null
CERN-PH-TH/2005-048
hep-ph
null
We investigate the dispersive contribution by radiative processes such as (pi- proton to neutron gamma) and (pi- proton to Delta gamma) to the pion-nucleon scattering lengths of charged pions in the heavy baryon limit. They give a large isospin violating contribution in the corresponding isoscalar scattering length, but only a small violation in the isovector one. These terms contribute 6.3(3)% to the 1s level shift of pionic hydrogen and give a chiral constant F_pi^2f_1=-25.8(8) MeV.
[ { "created": "Tue, 29 Mar 2005 11:42:03 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ericson", "T. E. O.", "", "2 and 3" ], [ "Ivanov", "A. N.", "", "2 and 3" ] ]
We investigate the dispersive contribution by radiative processes such as (pi- proton to neutron gamma) and (pi- proton to Delta gamma) to the pion-nucleon scattering lengths of charged pions in the heavy baryon limit. They give a large isospin violating contribution in the corresponding isoscalar scattering length, but only a small violation in the isovector one. These terms contribute 6.3(3)% to the 1s level shift of pionic hydrogen and give a chiral constant F_pi^2f_1=-25.8(8) MeV.
hep-ph/0511272
Andreas Metz
J.C. Collins, A.V. Efremov, K. Goeke, M. Grosse Perdekamp, S. Menzel, B. Meredith, A. Metz, P.Schweitzer
Sivers effect in Drell Yan at RHIC
10 pages, 7 figures, 1 table. v2: References and comments added, minor corrections
Phys.Rev.D73:094023,2006
10.1103/PhysRevD.73.094023
null
hep-ph
null
On the basis of a fit to the Sivers effect in deep-inelastic scattering, we make predictions for single-spin asymmetries in the Drell-Yan process at RHIC.
[ { "created": "Wed, 23 Nov 2005 13:40:12 GMT", "version": "v1" }, { "created": "Sat, 3 Jun 2006 16:14:41 GMT", "version": "v2" } ]
2008-11-26
[ [ "Collins", "J. C.", "" ], [ "Efremov", "A. V.", "" ], [ "Goeke", "K.", "" ], [ "Perdekamp", "M. Grosse", "" ], [ "Menzel", "S.", "" ], [ "Meredith", "B.", "" ], [ "Metz", "A.", "" ], [ "Schweitzer",...
On the basis of a fit to the Sivers effect in deep-inelastic scattering, we make predictions for single-spin asymmetries in the Drell-Yan process at RHIC.
0811.3001
Matthew Reece
Csaba Csaki, Matthew Reece, John Terning
The AdS/QCD Correspondence: Still Undelivered
32 pages, 15 figures; references added, minor changes, history clarified
JHEP 0905:067,2009
10.1088/1126-6708/2009/05/067
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the particle spectrum and event shapes in large N gauge theories in different regimes of the short-distance 't Hooft coupling, lambda. The mesons in the small lambda limit should have a Regge spectrum in order to agree with perturbation theory, while generically the large lambda theories with gravity duals produce spectra reminiscent of KK modes. We argue that these KK-like states are qualitatively different from QCD modes: they are deeply bound states which are sensitive to short distance interactions rather than the flux tube-like states expected in asymptotically free, confining gauge theories. In addition, we also find that the characteristic event shapes for the large lambda theories with gravity duals are close to spherical, very different from QCD-like (small lambda, small N) and Nambu-Goto-like (small lambda, large N) theories which have jets. This observation is in agreement with the conjecture of Strassler on event shapes in large 't Hooft coupling theories, which was recently proved by Hofman and Maldacena for the conformal case. This conclusion does not change even when considering soft-wall backgrounds in the gravity dual. The picture that emerges is the following: theories with small and large lambda are qualitatively different, while theories with small and large N are qualitatively similar. Thus it seems that it is the relative smallness of the 't Hooft coupling in QCD that prevents a reliable AdS/QCD correspondence from emerging, and that reproducing characteristic QCD-like behavior will require genuine stringy dynamics to be incorporated into any putative dual theory.
[ { "created": "Wed, 19 Nov 2008 20:43:00 GMT", "version": "v1" }, { "created": "Thu, 4 Dec 2008 16:51:27 GMT", "version": "v2" } ]
2009-05-29
[ [ "Csaki", "Csaba", "" ], [ "Reece", "Matthew", "" ], [ "Terning", "John", "" ] ]
We consider the particle spectrum and event shapes in large N gauge theories in different regimes of the short-distance 't Hooft coupling, lambda. The mesons in the small lambda limit should have a Regge spectrum in order to agree with perturbation theory, while generically the large lambda theories with gravity duals produce spectra reminiscent of KK modes. We argue that these KK-like states are qualitatively different from QCD modes: they are deeply bound states which are sensitive to short distance interactions rather than the flux tube-like states expected in asymptotically free, confining gauge theories. In addition, we also find that the characteristic event shapes for the large lambda theories with gravity duals are close to spherical, very different from QCD-like (small lambda, small N) and Nambu-Goto-like (small lambda, large N) theories which have jets. This observation is in agreement with the conjecture of Strassler on event shapes in large 't Hooft coupling theories, which was recently proved by Hofman and Maldacena for the conformal case. This conclusion does not change even when considering soft-wall backgrounds in the gravity dual. The picture that emerges is the following: theories with small and large lambda are qualitatively different, while theories with small and large N are qualitatively similar. Thus it seems that it is the relative smallness of the 't Hooft coupling in QCD that prevents a reliable AdS/QCD correspondence from emerging, and that reproducing characteristic QCD-like behavior will require genuine stringy dynamics to be incorporated into any putative dual theory.
hep-ph/9609353
Alexey Yu Umnikov
A.Yu. Umnikov (1 and 2), Han-xin He (2 and 3) and F.C. Khanna (3) ((1) INFN, Perugia, Italy, (2) University of Alberta, Edmonton, Canada, (3) CIAE, Beijing, P.R. China)
Chiral-Odd Structure Function h_1^D(x) and Tensor Charge of the Deuteron
10 pages, plus 3 Postscript figures
Phys.Lett. B398 (1997) 6-11
10.1016/S0370-2693(97)00195-0
null
hep-ph
null
The chiral-odd structure function h_{1}^D(x) and the tensor charge of the deuteron are studied within the Bethe-Salpeter formalism for the deuteron amplitude. Utilizing a simple model for the nucleon structure function, h_1^N, h_1^D(x) is calculated and the nuclear effects are analyzed.
[ { "created": "Fri, 13 Sep 1996 19:08:32 GMT", "version": "v1" } ]
2009-10-28
[ [ "Umnikov", "A. Yu.", "", "1 and 2" ], [ "He", "Han-xin", "", "2 and 3" ], [ "Khanna", "F. C.", "" ] ]
The chiral-odd structure function h_{1}^D(x) and the tensor charge of the deuteron are studied within the Bethe-Salpeter formalism for the deuteron amplitude. Utilizing a simple model for the nucleon structure function, h_1^N, h_1^D(x) is calculated and the nuclear effects are analyzed.
hep-ph/0401149
Sannino Francesco
Agnes Mocsy (Frankfurt Univ), Francesco Sannino (NORDITA), Kimmo Tuominen (Jyvaskyla Univ.)
Effective Lagrangians for QCD: Deconfinement and Chiral Symmetry Restoration
Invited review talk for the KIAS-APCTP International Symposium in Astro-Hadron Physics Compact Stars: Quest For New States of Dense Matter November 10 - 14, 2003
null
10.1142/9789812702524_0024
null
hep-ph hep-lat hep-th nucl-th
null
Effective Lagrangians for Quantum Chromodynamics (QCD) especially suited for understanding deconfinement and chiral symmetry restoration at nonzero temperature and matter density are reviewed. These effective theories allow one to study generic properties of phase transitions using non-order parameter fields without loosing the information encoded in the true order parameter. {}For the pure gauge theory we demonstrate that, near the deconfining phase transition, the center group symmetry is naturally linked to the conformal anomaly. Another relevant outcome is that when the theory contains also quarks we can explain the intertwining of chiral symmetry restoration and deconfinement for QCD with matter fields either in the fundamental or in the adjoint representation of the gauge group. As a test of our general approach we show our results to be applicable also at non zero baryon chemical potential. We also predict new testable substructures to be present in the phase diagram of quarks in the adjoint representation of the gauge group. Here we provide some new insights on the large $N$ limit of gauge theories by investigating the hadronic world. We propose that the world of infinite $N$ should already be well described when N=6 for QCD with two and three light flavors. Finally, we suggest possible future applications of our results for heavy ions collisions.
[ { "created": "Tue, 20 Jan 2004 20:23:15 GMT", "version": "v1" }, { "created": "Tue, 27 Jan 2004 22:32:17 GMT", "version": "v2" } ]
2017-08-23
[ [ "Mocsy", "Agnes", "", "Frankfurt Univ" ], [ "Sannino", "Francesco", "", "NORDITA" ], [ "Tuominen", "Kimmo", "", "Jyvaskyla Univ." ] ]
Effective Lagrangians for Quantum Chromodynamics (QCD) especially suited for understanding deconfinement and chiral symmetry restoration at nonzero temperature and matter density are reviewed. These effective theories allow one to study generic properties of phase transitions using non-order parameter fields without loosing the information encoded in the true order parameter. {}For the pure gauge theory we demonstrate that, near the deconfining phase transition, the center group symmetry is naturally linked to the conformal anomaly. Another relevant outcome is that when the theory contains also quarks we can explain the intertwining of chiral symmetry restoration and deconfinement for QCD with matter fields either in the fundamental or in the adjoint representation of the gauge group. As a test of our general approach we show our results to be applicable also at non zero baryon chemical potential. We also predict new testable substructures to be present in the phase diagram of quarks in the adjoint representation of the gauge group. Here we provide some new insights on the large $N$ limit of gauge theories by investigating the hadronic world. We propose that the world of infinite $N$ should already be well described when N=6 for QCD with two and three light flavors. Finally, we suggest possible future applications of our results for heavy ions collisions.
1607.06445
Mark Hertzberg
Mark P. Hertzberg, Ali Masoumi
Astrophysical Constraints on Singlet Scalars at LHC
19 pages, 4 figures. V4: updated to version published in JCAP
JCAP 04 (2017) 028
10.1088/1475-7516/2017/04/028
null
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the viability of new heavy gauge singlet scalar particles at colliders such as the LHC. Our original motivation for this study came from the possibility of a new heavy particle of mass ~ TeV decaying significantly into two photons at colliders, such as LHC, but our analysis applies more broadly. We show that there are significant constraints from astrophysics and cosmology on the simplest UV complete models that incorporate such new particles and its associated collider signal. The simplest and most obvious UV complete model that incorporates such signals is that it arises from a new singlet scalar (or pseudo-scalar) coupled to a new electrically charged and colored heavy fermion. Here we show that these new fermions (and anti-fermions) would be produced in the early universe, then form new color singlet heavy mesons with light quarks, obtain a non-negligible freeze-out abundance, and remain in kinetic equilibrium until decoupling. These heavy mesons possess interesting phenomenology, dependent on their charge, including forming new bound states with electrons and protons. We show that a significant number of these heavy states would survive for the age of the universe and an appreciable number would eventually be contained within the earth and solar system. We show that this leads to detectable consequences, including the production of highly energetic events from annihilations on earth, new spectral lines, and, spectacularly, the destabilization of stars. The lack of detection of these consequences rules out such simple UV completions, putting pressure on the viability of such new particles at LHC. To incorporate such a scalar would require either much more complicated UV completions or even further new physics that provides a decay channel for the associated fermion.
[ { "created": "Thu, 21 Jul 2016 19:52:08 GMT", "version": "v1" }, { "created": "Sun, 24 Jul 2016 03:39:24 GMT", "version": "v2" }, { "created": "Thu, 19 Jan 2017 07:38:41 GMT", "version": "v3" }, { "created": "Wed, 19 Apr 2017 20:41:01 GMT", "version": "v4" } ]
2017-04-21
[ [ "Hertzberg", "Mark P.", "" ], [ "Masoumi", "Ali", "" ] ]
We consider the viability of new heavy gauge singlet scalar particles at colliders such as the LHC. Our original motivation for this study came from the possibility of a new heavy particle of mass ~ TeV decaying significantly into two photons at colliders, such as LHC, but our analysis applies more broadly. We show that there are significant constraints from astrophysics and cosmology on the simplest UV complete models that incorporate such new particles and its associated collider signal. The simplest and most obvious UV complete model that incorporates such signals is that it arises from a new singlet scalar (or pseudo-scalar) coupled to a new electrically charged and colored heavy fermion. Here we show that these new fermions (and anti-fermions) would be produced in the early universe, then form new color singlet heavy mesons with light quarks, obtain a non-negligible freeze-out abundance, and remain in kinetic equilibrium until decoupling. These heavy mesons possess interesting phenomenology, dependent on their charge, including forming new bound states with electrons and protons. We show that a significant number of these heavy states would survive for the age of the universe and an appreciable number would eventually be contained within the earth and solar system. We show that this leads to detectable consequences, including the production of highly energetic events from annihilations on earth, new spectral lines, and, spectacularly, the destabilization of stars. The lack of detection of these consequences rules out such simple UV completions, putting pressure on the viability of such new particles at LHC. To incorporate such a scalar would require either much more complicated UV completions or even further new physics that provides a decay channel for the associated fermion.
1311.0593
Mei Huang
Danning Li, Mei Huang
Dynamical holographic QCD model: resembling renormalization group from ultraviolet to infrared
8 figures, Contribution for the Proceedings of the Karl Schwarzschild Meeting 2013 (Frankfurt, July 22-26 2013)
null
null
null
hep-ph gr-qc hep-lat hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Resembling the renormalization group from ultraviolet to infrared, we construct a dynamical holographic model in the graviton-dilaton-scalar framework, where the dilaton background field $\Phi$ and scalar field $X$ are responsible for the gluodynamics and chiral dynamics, respectively. At the UV boundary, the dilaton field is dual to the dimension-4 gluon operator, and the scalar field is dual to the dimension-3 quark-antiquark operator. The metric structure at IR is automatically deformed by the nonperturbative gluon condensation and chiral condensation in the vacuum. The produced scalar glueball spectra in the graviton-dilaton framework agree well with lattice data, and the light-flavor meson spectra generated in the graviton-dilaton-scalar framework are in well agreement with experimental data. Both the chiral symmetry breaking and linear confinement are realized in this dynamical holographic QCD model. The necessary condition for the existence of linear quark potential is discussed, and the pion form factor is also investigated in the dynamical holographic QCD model.
[ { "created": "Mon, 4 Nov 2013 06:46:03 GMT", "version": "v1" } ]
2013-11-05
[ [ "Li", "Danning", "" ], [ "Huang", "Mei", "" ] ]
Resembling the renormalization group from ultraviolet to infrared, we construct a dynamical holographic model in the graviton-dilaton-scalar framework, where the dilaton background field $\Phi$ and scalar field $X$ are responsible for the gluodynamics and chiral dynamics, respectively. At the UV boundary, the dilaton field is dual to the dimension-4 gluon operator, and the scalar field is dual to the dimension-3 quark-antiquark operator. The metric structure at IR is automatically deformed by the nonperturbative gluon condensation and chiral condensation in the vacuum. The produced scalar glueball spectra in the graviton-dilaton framework agree well with lattice data, and the light-flavor meson spectra generated in the graviton-dilaton-scalar framework are in well agreement with experimental data. Both the chiral symmetry breaking and linear confinement are realized in this dynamical holographic QCD model. The necessary condition for the existence of linear quark potential is discussed, and the pion form factor is also investigated in the dynamical holographic QCD model.
hep-ph/0608260
Dmitriy Kulikov Alexandrovitch
D. A. Kulikov, R. S. Tutik
Regge trajectories of the Klein-Gordon equation with non-minimal interaction
8 pages, 1 figure
Dniepropetrovsk National University Scientifical Herald. Series Physics and Radiophysics, Vol.11, No 2, pp. 68-74 (2004)
null
null
hep-ph
null
A semiclassical method of deriving Regge trajectories for the bound states of the Klein-Gordon equation with the interaction introduced in a non-minimal way is proposed. The method is applied to construction of the quarkonium Regge trajectories. It is found that under the relativistic generalization of the Cornell potential the Regge trajectories of charmonium are in the same good agreement with experimental data for introducing the confinement part of potential either in the minimal, or non-minimal way.
[ { "created": "Wed, 23 Aug 2006 06:06:34 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kulikov", "D. A.", "" ], [ "Tutik", "R. S.", "" ] ]
A semiclassical method of deriving Regge trajectories for the bound states of the Klein-Gordon equation with the interaction introduced in a non-minimal way is proposed. The method is applied to construction of the quarkonium Regge trajectories. It is found that under the relativistic generalization of the Cornell potential the Regge trajectories of charmonium are in the same good agreement with experimental data for introducing the confinement part of potential either in the minimal, or non-minimal way.
hep-ph/9707398
Bergmann Sven
Sven Bergmann
The Solar Neutrino Problem in the Presence of Flavor Changing Neutrino Interactions
24 pages, 14 eps-figures, Latex. References to work by Fogli and Lisi, where implications of results from Gallium experiments are first discussed, and to work by Petcov, where eq. (9) is derived, were added. For a second version of the paper containing more figures in better resolution, see http://www.weizmann.ac.il/~ftsven
Nucl.Phys. B515 (1998) 363-383
10.1016/S0550-3213(97)00794-3
WIS-97/19/Jul-PH
hep-ph
null
We study the effects of flavor changing neutrino interactions on the resonant conversion of solar neutrinos. In particular, we describe how the regions in the $Delta m^2 - sin^2 2theta$ plane that are consistent with the four solar neutrino experiments are modified for different strengths of New Physics neutrino interactions.
[ { "created": "Sat, 19 Jul 1997 02:43:15 GMT", "version": "v1" }, { "created": "Sat, 16 Aug 1997 15:11:27 GMT", "version": "v2" } ]
2009-10-30
[ [ "Bergmann", "Sven", "" ] ]
We study the effects of flavor changing neutrino interactions on the resonant conversion of solar neutrinos. In particular, we describe how the regions in the $Delta m^2 - sin^2 2theta$ plane that are consistent with the four solar neutrino experiments are modified for different strengths of New Physics neutrino interactions.
hep-ph/9502291
Matthias Steinhauser
K.G. Chetyrkin, J.H. Kuehn, M. Steinhauser
Corrections of order ${\cal O}(G_F M_t^2 \as^2)$ to the $\rho$ parameter
10 pages, Latex, 1 figure contained in a separate file The complete paper, including figures, is also available at (129.13.102.139) ftp://ttpux2.physik.uni-karlsruhe.de/ttp95-03/ttp95-03.ps, or via www at http://ttpux2.physik.uni-karlsruhe.de/cgi-bin/preprints/
Phys.Lett. B351 (1995) 331-338
10.1016/0370-2693(95)00380-4
TTP95-03
hep-ph
null
The three-loop QCD corrections to the $\rho$ parameter from top and bottom quark loops are calculated. The result differs from the one recently calculated by Avdeev et al. As function of the pole mass the numerical value is given by $\drho=\frac{3G_F M_t^2}{8\sqrt{2}\pi^2}(1- 2.8599 \api - 14.594 (\api)^2 )$.
[ { "created": "Mon, 13 Feb 1995 15:51:40 GMT", "version": "v1" }, { "created": "Tue, 14 Feb 1995 08:17:18 GMT", "version": "v2" } ]
2016-09-01
[ [ "Chetyrkin", "K. G.", "" ], [ "Kuehn", "J. H.", "" ], [ "Steinhauser", "M.", "" ] ]
The three-loop QCD corrections to the $\rho$ parameter from top and bottom quark loops are calculated. The result differs from the one recently calculated by Avdeev et al. As function of the pole mass the numerical value is given by $\drho=\frac{3G_F M_t^2}{8\sqrt{2}\pi^2}(1- 2.8599 \api - 14.594 (\api)^2 )$.
hep-ph/0403289
Kacper Zalewski
K. Zalewski
Remark on the core/halo model of Bose-Einstein correlations in multiple particle production processes
4 pages, Latex, no figures, to be published in Acta Phys. Pol. B
Acta Phys.Polon. B35 (2004) 1747-1750
null
null
hep-ph
null
The core/halo model describes the Bose-Einstein correlations in multihadron production taking into account the effects of long-lived resonances. The model contains the combinatorial coefficients alpha_j which were originally calculated from a recurrence relation. We show that alpha_j is the integer nearest to j!/e.
[ { "created": "Tue, 30 Mar 2004 10:15:53 GMT", "version": "v1" } ]
2007-05-23
[ [ "Zalewski", "K.", "" ] ]
The core/halo model describes the Bose-Einstein correlations in multihadron production taking into account the effects of long-lived resonances. The model contains the combinatorial coefficients alpha_j which were originally calculated from a recurrence relation. We show that alpha_j is the integer nearest to j!/e.
hep-ph/9712275
F. Javier Rico
Fernando Cornet and Javier Rico (Universidad de Granada, Spain)
Physics Beyond the Standard Model at HERA
15 pages. LaTeX2e, 3 Postscript figures included. Talk presented by F. Cornet at the XXI International School on Theoretical Physics, Ustron (Poland), September 1997. To appear in Acta Physica Polonica B
Acta Phys.Polon.B28:2439-2451,1997
null
UG-FT-83/97
hep-ph
null
This talk is divided in two parts. In the first one we discuss the signals of the Minimal Supersymmetric Standard Model through the production of \tilde{e} \tilde{q}. The second part is devoted to contact terms. The bounds on the mass scale Lambda obtained from atomic parity violation experiments and from LEP are reviewed. Afterwards, we show that the excess of events at high Q^2 observed at HERA could be explained in terms of these contact terms.
[ { "created": "Fri, 5 Dec 1997 12:21:55 GMT", "version": "v1" } ]
2011-04-15
[ [ "Cornet", "Fernando", "", "Universidad de Granada, Spain" ], [ "Rico", "Javier", "", "Universidad de Granada, Spain" ] ]
This talk is divided in two parts. In the first one we discuss the signals of the Minimal Supersymmetric Standard Model through the production of \tilde{e} \tilde{q}. The second part is devoted to contact terms. The bounds on the mass scale Lambda obtained from atomic parity violation experiments and from LEP are reviewed. Afterwards, we show that the excess of events at high Q^2 observed at HERA could be explained in terms of these contact terms.
2203.00290
Peter Landshoff
A Donnachie and P V Landshoff
Lack of evidence for an odderon at small t
4 pages, equation (1) corrected
null
10.1016/j.physletb.2022.137199
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
It is fundamental that the phase of an elastic scattering amplitude is related to its energy variation. We repeat a previous fit to proton-proton and proton-antiproton elastic scattering data from 13 to 13000 GeV, taking better account of the very high accuracy of the 13 TeV data. The conclusion remains that there is no evidence for the existence of an odderon in the small-t data
[ { "created": "Tue, 1 Mar 2022 08:45:54 GMT", "version": "v1" }, { "created": "Sun, 6 Mar 2022 12:57:56 GMT", "version": "v2" }, { "created": "Sun, 9 Oct 2022 06:58:12 GMT", "version": "v3" } ]
2022-10-11
[ [ "Donnachie", "A", "" ], [ "Landshoff", "P V", "" ] ]
It is fundamental that the phase of an elastic scattering amplitude is related to its energy variation. We repeat a previous fit to proton-proton and proton-antiproton elastic scattering data from 13 to 13000 GeV, taking better account of the very high accuracy of the 13 TeV data. The conclusion remains that there is no evidence for the existence of an odderon in the small-t data
1112.1014
Kwang Sik Jeong
Kwang Sik Jeong, Yutaro Shoji, Masahiro Yamaguchi
Peccei-Quinn invariant extension of the NMSSM
22 pages, 3 figures; published version
null
10.1007/JHEP04(2012)022
TU-895
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study a Peccei-Quinn invariant extension of the next-to-minimal supersymmetric Standard Model (NMSSM), which turns out to be free from the tadpole and domain wall problems. Having a non-renormalizable coupling to the axion superfield, the SM singlet added to the Higgs sector can naturally generate an effective Higgs mu term around the weak scale. In the model, the lightest neutralino is dominated by the singlino, which gets a mass only through mixing with the neutral Higgsinos. We explore the phenomenological consequences resulting from the existence of such a relatively light neutralino. The coupling of the SM singlet to the Higgs doublets is constrained by the experimental bound on the invisible Z-boson decay width. Under this constraint, we examine the properties of the SM-like Higgs boson paying attention to its mass and decays. We also demonstrate a UV completion of the model in SU(5) grand unified theory with a missing-partner mechanism.
[ { "created": "Mon, 5 Dec 2011 17:47:03 GMT", "version": "v1" }, { "created": "Fri, 9 Dec 2011 10:35:05 GMT", "version": "v2" }, { "created": "Wed, 25 Jan 2012 10:48:43 GMT", "version": "v3" }, { "created": "Tue, 19 Jun 2012 12:22:12 GMT", "version": "v4" } ]
2015-06-03
[ [ "Jeong", "Kwang Sik", "" ], [ "Shoji", "Yutaro", "" ], [ "Yamaguchi", "Masahiro", "" ] ]
We study a Peccei-Quinn invariant extension of the next-to-minimal supersymmetric Standard Model (NMSSM), which turns out to be free from the tadpole and domain wall problems. Having a non-renormalizable coupling to the axion superfield, the SM singlet added to the Higgs sector can naturally generate an effective Higgs mu term around the weak scale. In the model, the lightest neutralino is dominated by the singlino, which gets a mass only through mixing with the neutral Higgsinos. We explore the phenomenological consequences resulting from the existence of such a relatively light neutralino. The coupling of the SM singlet to the Higgs doublets is constrained by the experimental bound on the invisible Z-boson decay width. Under this constraint, we examine the properties of the SM-like Higgs boson paying attention to its mass and decays. We also demonstrate a UV completion of the model in SU(5) grand unified theory with a missing-partner mechanism.
hep-ph/9311360
Papageorgiu
E. Papageorgiu
Neutrino properties from maximally-predictive GUT models and the structure of the heavy Majorana sector
39, LATEX, LPTHE45
Z.Phys. C65 (1995) 135-150
10.1007/BF01571314
null
hep-ph
null
Starting from a complete set of possible parametrisations of the quark-mass matrices that have the maximum number of texture zeros at the grand unification scale, and the Georgi-Jarlskog mass relations, we classify the neutrino spectra with respect to the unknown structure of the heavy Majorana sector. The results can be casted into a small number of phenomenologically distinct classes of neutrino spectra, characterised by universal mass-hierarchy and oscillation patterns. One finds that the neutrino masses reflect the natural hierarchy among the three generations and obey the quadratic seesaw, for most GUT models that contain a rather unsophisticated Majorana sector. A scenario with $\nu_{\tau}$ as the missing hot dark matter component and $\nu_e\leftrightarrow \nu_{\mu}$ oscillations accounting for the solar neutrino deficit comes naturally out of this type of models and is very close to the experimental limit of confirmation or exclusion. In contrast, in the presence of a strong hierarchy of heavy scales or/and some extra symmetries in the Majorana mass matrix, this natural hierarchy gets distorted or even reversed. This fact can become a link between searches for neutrino oscillations and searches for discrete symmetries close to the Planck scale.
[ { "created": "Wed, 24 Nov 1993 18:38:11 GMT", "version": "v1" } ]
2015-06-25
[ [ "Papageorgiu", "E.", "" ] ]
Starting from a complete set of possible parametrisations of the quark-mass matrices that have the maximum number of texture zeros at the grand unification scale, and the Georgi-Jarlskog mass relations, we classify the neutrino spectra with respect to the unknown structure of the heavy Majorana sector. The results can be casted into a small number of phenomenologically distinct classes of neutrino spectra, characterised by universal mass-hierarchy and oscillation patterns. One finds that the neutrino masses reflect the natural hierarchy among the three generations and obey the quadratic seesaw, for most GUT models that contain a rather unsophisticated Majorana sector. A scenario with $\nu_{\tau}$ as the missing hot dark matter component and $\nu_e\leftrightarrow \nu_{\mu}$ oscillations accounting for the solar neutrino deficit comes naturally out of this type of models and is very close to the experimental limit of confirmation or exclusion. In contrast, in the presence of a strong hierarchy of heavy scales or/and some extra symmetries in the Majorana mass matrix, this natural hierarchy gets distorted or even reversed. This fact can become a link between searches for neutrino oscillations and searches for discrete symmetries close to the Planck scale.
1903.09891
Xun-Jie Xu
Jonathan M. Link, Xun-Jie Xu
Searching for BSM neutrino interactions in dark matter detectors
fig. 7 added, matches the published version
JHEP 1908 (2019) 004
10.1007/JHEP08(2019)004
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neutrino interactions beyond the Standard Model (BSM) are theoretically well motivated and have an important impact on the future precision measurement of neutrino oscillation. In this work, we study the sensitivity of a multi-ton-scale liquid Xenon dark matter detector equipped with an intense radiative neutrino source to various BSM neutrino-electron interactions. We consider the conventional Non-Standard Interactions (NSIs), other more generalized four-fermion interactions including scalar and tensor forms, and light-boson mediated interactions. The work shows that with realistic experimental setups, one can achieve unprecedented sensitivity to these BSM neutrino-electron interactions.
[ { "created": "Sat, 23 Mar 2019 21:54:52 GMT", "version": "v1" }, { "created": "Fri, 2 Aug 2019 12:14:09 GMT", "version": "v2" } ]
2019-08-05
[ [ "Link", "Jonathan M.", "" ], [ "Xu", "Xun-Jie", "" ] ]
Neutrino interactions beyond the Standard Model (BSM) are theoretically well motivated and have an important impact on the future precision measurement of neutrino oscillation. In this work, we study the sensitivity of a multi-ton-scale liquid Xenon dark matter detector equipped with an intense radiative neutrino source to various BSM neutrino-electron interactions. We consider the conventional Non-Standard Interactions (NSIs), other more generalized four-fermion interactions including scalar and tensor forms, and light-boson mediated interactions. The work shows that with realistic experimental setups, one can achieve unprecedented sensitivity to these BSM neutrino-electron interactions.
1402.5603
Dorin Weissman
Jacob Sonnenschein and Dorin Weissman
Rotating strings confronting PDG mesons
v2: typos fixed and reference added, 47 pages / v3: added section in appendix detailing the states used in the fits, 51 pages
JHEP 1408 (2014) 013
10.1007/JHEP08(2014)013
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the model of mesons as rotating strings with massive endpoints and confront it with meson spectra. We look at Regge trajectories both in the (J,M2) and (n,M2) planes, where J and n are the angular momentum and radial excitation number respectively. We start from states comprised of u and d quarks alone, move on to trajectories involving s and c quarks, and finally analyze the trajectories of the heaviest observed b-bbar mesons. The endpoint masses provide the needed transition between the linear Regge trajectories of the light mesons to the deviations from linear behavior encountered for the heavier mesons, all in the confines of the same simple model. From our fits we extract the values of the quark endpoint masses, the Regge slope (string tension) and quantum intercept. The model also allows for a universal fit where with a single value of the Regge slope we fit all the (J,M2) trajectories involving u, d, s, and c quarks. We include a list of predictions for higher mesons in both J and n.
[ { "created": "Sun, 23 Feb 2014 13:05:05 GMT", "version": "v1" }, { "created": "Mon, 7 Apr 2014 09:44:49 GMT", "version": "v2" }, { "created": "Sat, 21 Jun 2014 15:23:33 GMT", "version": "v3" } ]
2014-08-07
[ [ "Sonnenschein", "Jacob", "" ], [ "Weissman", "Dorin", "" ] ]
We revisit the model of mesons as rotating strings with massive endpoints and confront it with meson spectra. We look at Regge trajectories both in the (J,M2) and (n,M2) planes, where J and n are the angular momentum and radial excitation number respectively. We start from states comprised of u and d quarks alone, move on to trajectories involving s and c quarks, and finally analyze the trajectories of the heaviest observed b-bbar mesons. The endpoint masses provide the needed transition between the linear Regge trajectories of the light mesons to the deviations from linear behavior encountered for the heavier mesons, all in the confines of the same simple model. From our fits we extract the values of the quark endpoint masses, the Regge slope (string tension) and quantum intercept. The model also allows for a universal fit where with a single value of the Regge slope we fit all the (J,M2) trajectories involving u, d, s, and c quarks. We include a list of predictions for higher mesons in both J and n.
hep-ph/9908522
Alan M. Nathan
Alan M. Nathan
Real Compton Scattering from the Proton
Contribution to Workshop on Exclusive & Semi-Exclusive Processes at High Momentum Transfer, JLab, May 20-22, 1999 8 pages, 4 figures
null
null
null
hep-ph
null
Real Compton Scattering on the proton in the hard scattering regime is investigated. Recent theoretical developments are reviewed. Plans for new experimental studies at Jefferson Laboratory are presented.
[ { "created": "Tue, 31 Aug 1999 16:40:42 GMT", "version": "v1" } ]
2007-05-23
[ [ "Nathan", "Alan M.", "" ] ]
Real Compton Scattering on the proton in the hard scattering regime is investigated. Recent theoretical developments are reviewed. Plans for new experimental studies at Jefferson Laboratory are presented.