id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1312.5456 | Nikolai Kivel | N. Kivel, M. Vanderhaeghen | QCD radiative corrections to the soft spectator contribution in the wide
angle Compton scattering | 28 pages, 10 figures | null | 10.1016/j.nuclphysb.2014.03.019 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive the complete factorization formula for the leading power
contribution in wide angle Compton scattering. It consists of the soft- and
hard-spectator contributions. The hard-spectator contribution is well known and
defined in the form of the convolution of a hard kernel with the nucleon
distribution amplitudes. The soft-spectator contribution describes the
scattering which involves the soft modes. We use the soft collinear effective
theory in order to define this term in a field theoretical approach. Using the
SCET framework we provide the proof of the factorization formula. We also
compute the next-to-leading QCD corrections to the hard coefficient function of
the soft spectator contribution and perform a phenomenological analysis of
existing experimental data within the developed formalism.
| [
{
"created": "Thu, 19 Dec 2013 09:30:04 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Kivel",
"N.",
""
],
[
"Vanderhaeghen",
"M.",
""
]
] | We derive the complete factorization formula for the leading power contribution in wide angle Compton scattering. It consists of the soft- and hard-spectator contributions. The hard-spectator contribution is well known and defined in the form of the convolution of a hard kernel with the nucleon distribution amplitudes. The soft-spectator contribution describes the scattering which involves the soft modes. We use the soft collinear effective theory in order to define this term in a field theoretical approach. Using the SCET framework we provide the proof of the factorization formula. We also compute the next-to-leading QCD corrections to the hard coefficient function of the soft spectator contribution and perform a phenomenological analysis of existing experimental data within the developed formalism. |
hep-ph/0205264 | Emilian Dudas | Emilian Dudas and Carlos A. Savoy | Multiple seesaw at low energy | 9 pages, LaTeX. Dedicated to Stefan Pokorski on the occasion of his
60th birthday | Acta Phys.Polon. B33 (2002) 2547-2558 | null | LPT-ORSAY 02-38, CPHT RR 038.0502, Saclay t02/062 | hep-ph | null | A new mechanism for generating neutrino masses without a high-energy mass
scale is proposed. The mechanism needs a fundamental mass scale M in the
100-1000 TeV region and a minimal field content beyond the Standard Model one
containing a pair of fermion singlets and a pair of weak doublet fermions for
each neutrino mass, all of them with a mass of order M. The neutrino mass
appears by a multiple seesaw-type tree-level diagram. We provide an explicit
model based on supersymmetry and an abelian symmetry which provides the
required fermion mass matrix. The mechanism is natural in the context of string
theories with a low fundamental scale. Within an explicit example where the
abelian symmetry is also responsible for the generation of fermion masses and
mixings, we give a hint relating the fermion mass matrices and the weak mixing
angle. By assuming the weak-strong couplings unification, one naturally finds
$\sin^2 \theta_w = 1/4$ at the fundamental scale.
| [
{
"created": "Thu, 23 May 2002 12:03:08 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dudas",
"Emilian",
""
],
[
"Savoy",
"Carlos A.",
""
]
] | A new mechanism for generating neutrino masses without a high-energy mass scale is proposed. The mechanism needs a fundamental mass scale M in the 100-1000 TeV region and a minimal field content beyond the Standard Model one containing a pair of fermion singlets and a pair of weak doublet fermions for each neutrino mass, all of them with a mass of order M. The neutrino mass appears by a multiple seesaw-type tree-level diagram. We provide an explicit model based on supersymmetry and an abelian symmetry which provides the required fermion mass matrix. The mechanism is natural in the context of string theories with a low fundamental scale. Within an explicit example where the abelian symmetry is also responsible for the generation of fermion masses and mixings, we give a hint relating the fermion mass matrices and the weak mixing angle. By assuming the weak-strong couplings unification, one naturally finds $\sin^2 \theta_w = 1/4$ at the fundamental scale. |
2406.02896 | Gennady Kozlov | G.A. Kozlov | Random fluctuation walk in the boson star formation process | 11 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct the mechanism of formation of the scalar boson star (BS) having
a hierarchy of self-similar "lumps" of dark matter (DM) built into the
probability distribution function of allowed steps. It can ensure to study the
dynamics of the BS formation through the "cross-over" between the free scalar
DM and the compact condensate (CC) phase in one-dimensional model of the random
fluctuation walk. The main inputs are the random fluctuating weight $\lambda <
1$, the fundamental fluctuating length $\xi (\lambda)$ and the parameter $a >1$
of the spatial separation between the DM "lumps" inside the BS. The solution to
the functional equation for the characteristic probability to find the free
scalar DM and the CC phase is obtained. The time evolution of the probability
to form the DM "lump" (growth of the BS) is presented with the power-law
cascades expression depending on $\lambda$ and $a$. The special cases for
$\lambda$ in terms of the energy densities of the BS ($\rho_\star$) and the DM
($\rho_\odot$), as well as the Bose-Einstein correlation function for two
scalar DM particles, are considered. The lower bounds on the critical
temperature at the "cross-over" depending on $\rho_\odot$, $\rho_\star$, the
average multiplicities of the scalar DM particles and the parameters related to
the chaotically behaviour of the particles are obtained.
| [
{
"created": "Wed, 5 Jun 2024 03:35:07 GMT",
"version": "v1"
}
] | 2024-06-06 | [
[
"Kozlov",
"G. A.",
""
]
] | We construct the mechanism of formation of the scalar boson star (BS) having a hierarchy of self-similar "lumps" of dark matter (DM) built into the probability distribution function of allowed steps. It can ensure to study the dynamics of the BS formation through the "cross-over" between the free scalar DM and the compact condensate (CC) phase in one-dimensional model of the random fluctuation walk. The main inputs are the random fluctuating weight $\lambda < 1$, the fundamental fluctuating length $\xi (\lambda)$ and the parameter $a >1$ of the spatial separation between the DM "lumps" inside the BS. The solution to the functional equation for the characteristic probability to find the free scalar DM and the CC phase is obtained. The time evolution of the probability to form the DM "lump" (growth of the BS) is presented with the power-law cascades expression depending on $\lambda$ and $a$. The special cases for $\lambda$ in terms of the energy densities of the BS ($\rho_\star$) and the DM ($\rho_\odot$), as well as the Bose-Einstein correlation function for two scalar DM particles, are considered. The lower bounds on the critical temperature at the "cross-over" depending on $\rho_\odot$, $\rho_\star$, the average multiplicities of the scalar DM particles and the parameters related to the chaotically behaviour of the particles are obtained. |
hep-ph/9511407 | Ulrich Nierste | Ulrich Nierste and Kurt Riesselmann | Higgs Sector Renormalization Group in the MS-bar and OMS Scheme | 26 pages, uses RevTex, epsf and rotate, 13 figures included as
separate uuencoded packed file. A complete PostScript version available at
http://www.cip.physik.tu-muenchen.de/tumphy/d/T30d/PAPERS/
TUM-HEP-224-95.ps.gz | Phys.Rev.D53:6638-6652,1996 | 10.1103/PhysRevD.53.6638 | TUM-HEP-224/95, TUM-T31-90/95 | hep-ph | null | We discuss different aspects of the Higgs self-interaction in the MS-bar and
the on-mass-shell (OMS) scheme. The running coupling \lambda(\mu) is
investigated in great detail. The three-loop coefficient of the \beta-function
in the OMS scheme is derived, and the three-loop running coupling is
calculated. The breakdown of perturbation theory for large Higgs masses M_H is
analyzed in three physical observables for which two-loop results are known.
Requiring the dependence on the renormalization scale to diminish
order-by-order in \lambda, we find that perturbation theory breaks down for
M_H=O(700 GeV) in Higgs decays. Similarly, M_H must be smaller than O(400 GeV)
for perturbatively calculated cross sections to be trustworthy up to cm
energies of O(2 TeV). If the Higgs sector shall be perturbative up to the GUT
scale, the Higgs must be lighter than O(150 GeV). For the two-loop observables
examined, the apparent convergence of the perturbation series is better in the
OMS scheme than in the MS-bar scheme.
| [
{
"created": "Fri, 24 Nov 1995 13:46:25 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Nov 1995 14:17:02 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Nierste",
"Ulrich",
""
],
[
"Riesselmann",
"Kurt",
""
]
] | We discuss different aspects of the Higgs self-interaction in the MS-bar and the on-mass-shell (OMS) scheme. The running coupling \lambda(\mu) is investigated in great detail. The three-loop coefficient of the \beta-function in the OMS scheme is derived, and the three-loop running coupling is calculated. The breakdown of perturbation theory for large Higgs masses M_H is analyzed in three physical observables for which two-loop results are known. Requiring the dependence on the renormalization scale to diminish order-by-order in \lambda, we find that perturbation theory breaks down for M_H=O(700 GeV) in Higgs decays. Similarly, M_H must be smaller than O(400 GeV) for perturbatively calculated cross sections to be trustworthy up to cm energies of O(2 TeV). If the Higgs sector shall be perturbative up to the GUT scale, the Higgs must be lighter than O(150 GeV). For the two-loop observables examined, the apparent convergence of the perturbation series is better in the OMS scheme than in the MS-bar scheme. |
1312.3949 | Chien-Yi Chen | Chien-Yi Chen, Michael Freid, Marc Sher | The Next-to-Minimal Two Higgs Doublet Model | 9 pages, 3 figures, matches published version, references added | Phys. Rev. D 89, 075009 (2014) | 10.1103/PhysRevD.89.075009 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The simplest extension of the Two Higgs Doublet Model is the addition of a
real scalar singlet, S. The effects of mixing between the singlet and the
doublets can be manifested in two ways. It can modify the couplings of the 126
GeV Higgs boson, h, and it can lead to direct detection of the heavy Higgs at
the LHC. In this paper, we show that in the type-I model, for heavy Higgs
masses in the 200-600 GeV range, the latter effect will be detected earlier
than the former for most of parameter space. Should no such Higgs be discovered
in this mass range, then the upper limit on the mixing will be sufficiently
strong such that there will be no significant effects on the couplings of the h
for most of parameter space. The reverse is true in the type-II model, the
limits from measurements of the couplings of the h will dominate over the
limits from non-observation of the heavy Higgs.
| [
{
"created": "Fri, 13 Dec 2013 21:00:03 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Mar 2014 04:27:38 GMT",
"version": "v2"
}
] | 2014-04-23 | [
[
"Chen",
"Chien-Yi",
""
],
[
"Freid",
"Michael",
""
],
[
"Sher",
"Marc",
""
]
] | The simplest extension of the Two Higgs Doublet Model is the addition of a real scalar singlet, S. The effects of mixing between the singlet and the doublets can be manifested in two ways. It can modify the couplings of the 126 GeV Higgs boson, h, and it can lead to direct detection of the heavy Higgs at the LHC. In this paper, we show that in the type-I model, for heavy Higgs masses in the 200-600 GeV range, the latter effect will be detected earlier than the former for most of parameter space. Should no such Higgs be discovered in this mass range, then the upper limit on the mixing will be sufficiently strong such that there will be no significant effects on the couplings of the h for most of parameter space. The reverse is true in the type-II model, the limits from measurements of the couplings of the h will dominate over the limits from non-observation of the heavy Higgs. |
2203.10538 | Serge Bondarenko Dr. | S.G. Bondarenko (1), L.V. Kalinovskaya (2), L.A. Rumyantsev (2), V.L.
Yermolchyk (2,3) ((1) Bogoliubov Laboratory of Theoretical Physics, Joint
Institute for Nuclear Research, Dubna, 141980 Russia, (2) Dzhelepov
Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, Dubna,
141980 Russia, (3) Institute for Nuclear Problems, Belarusian State
University, Minsk, 220006 Belarus) | One-loop electroweak radiative corrections to polarized M{\o}ller
scattering | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This work is devoted to a theoretical description of polarized M{\o}ller
scattering. Complete one-loop electroweak radiative corrections are calculated
in the helicity amplitude approach with allowance for the exact dependence on
the muon mass. Numerical results are presented for integrated unpolarized and
polarized cross sections as well as angular differential distributions.
Calculations are performed using ReneSANCe Monte Carlo generator and MCSANC
Monte Carlo integrator.
| [
{
"created": "Sun, 20 Mar 2022 12:06:42 GMT",
"version": "v1"
}
] | 2022-03-22 | [
[
"Bondarenko",
"S. G.",
""
],
[
"Kalinovskaya",
"L. V.",
""
],
[
"Rumyantsev",
"L. A.",
""
],
[
"Yermolchyk",
"V. L.",
""
]
] | This work is devoted to a theoretical description of polarized M{\o}ller scattering. Complete one-loop electroweak radiative corrections are calculated in the helicity amplitude approach with allowance for the exact dependence on the muon mass. Numerical results are presented for integrated unpolarized and polarized cross sections as well as angular differential distributions. Calculations are performed using ReneSANCe Monte Carlo generator and MCSANC Monte Carlo integrator. |
0809.3866 | Melahat Bayar | M. Bayar, K. Azizi | Semileptonic $B_{q}\to D^{\ast}_{q}l\nu $ $(q=s, d, u)$ transitions in
QCD | 4 pages, 4 figures and 3 tables. To be published in the proceedings
of the 14th International QCD Conference (QCD 08), Montpellier, France, 7-12
July 2008 | null | 10.1016/j.nuclphysbps.2008.12.089 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The form factors relevant to $B_{q}\to D^{\ast}_{q}(J^{P}=1^{-})\ell\nu$
$(q=s, d, u)$ decays are calculated in the framework of the three point QCD sum
rules approach. The heavy quark effective theory prediction of the form factors
are obtained. The total decay width and branching ratio for these decays are
also evaluated using the $q^2$ dependencies of these form factors.
| [
{
"created": "Tue, 23 Sep 2008 08:39:58 GMT",
"version": "v1"
}
] | 2009-11-13 | [
[
"Bayar",
"M.",
""
],
[
"Azizi",
"K.",
""
]
] | The form factors relevant to $B_{q}\to D^{\ast}_{q}(J^{P}=1^{-})\ell\nu$ $(q=s, d, u)$ decays are calculated in the framework of the three point QCD sum rules approach. The heavy quark effective theory prediction of the form factors are obtained. The total decay width and branching ratio for these decays are also evaluated using the $q^2$ dependencies of these form factors. |
hep-ph/9310234 | null | A. Anselm, M. Anselmino, F. Murgia and M.G. Ryskin | On the Parton Interpretation of Quark Fragmentation into Hadrons with
Different Spins | 10 pages (no figures), Plain TEX , report DFTT 48/93 | JETP Lett. 60 (1994) 496-504 | null | null | hep-ph | null | We calculate the spin density matrix of the hadron $h$ created via quark
fragmentation in the process $e^-e^+ \to q\bar q \to h + X$. In the case of
$h=\Lambda$ the experimental data could possibly elucidate the problem of
$s$-quark contribution to the spin of the $\Lambda$-hyperon, to be compared
with the case of the proton (``spin crisis''). Generally we find that for
hadrons with spin 1/2 the parton description, using only probabilities, works
much better than for vector particles, since in the former case the non
diagonal matrix elements of the hadron spin density matrix are suppressed by a
small factor $p_T/(z\sqrt s)$, where $p_T$ is the hadron transverse momentum
inside the jet.
| [
{
"created": "Wed, 6 Oct 1993 14:36:52 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Anselm",
"A.",
""
],
[
"Anselmino",
"M.",
""
],
[
"Murgia",
"F.",
""
],
[
"Ryskin",
"M. G.",
""
]
] | We calculate the spin density matrix of the hadron $h$ created via quark fragmentation in the process $e^-e^+ \to q\bar q \to h + X$. In the case of $h=\Lambda$ the experimental data could possibly elucidate the problem of $s$-quark contribution to the spin of the $\Lambda$-hyperon, to be compared with the case of the proton (``spin crisis''). Generally we find that for hadrons with spin 1/2 the parton description, using only probabilities, works much better than for vector particles, since in the former case the non diagonal matrix elements of the hadron spin density matrix are suppressed by a small factor $p_T/(z\sqrt s)$, where $p_T$ is the hadron transverse momentum inside the jet. |
1007.2992 | Rui Santos | Renato Guedes, Rui Santos and Miguel Won | top FCNC physics at a Linear Collider after the LHC | Talk presented at at LCWS10/ILC10. 7 pages, 5 figures | null | null | SHEP-10-21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Flavour changing neutral currents are absent at tree level in the Standard
Model (SM) and are highly suppressed at higher orders due the
Glashow-Iliopoulos-Maiani mechanism. Hence, any evidence of such currents
related to the top quark will definitely signal new physics beyond the SM. In
this work we will discuss how an electron-positron collider can contribute to
the field after the Large Hadron Collider (LHC) has collected at least 100
fb^{-1} of integrated luminosity operating at sqrt{s} = 14 TeV.
| [
{
"created": "Sun, 18 Jul 2010 11:44:13 GMT",
"version": "v1"
}
] | 2010-07-20 | [
[
"Guedes",
"Renato",
""
],
[
"Santos",
"Rui",
""
],
[
"Won",
"Miguel",
""
]
] | Flavour changing neutral currents are absent at tree level in the Standard Model (SM) and are highly suppressed at higher orders due the Glashow-Iliopoulos-Maiani mechanism. Hence, any evidence of such currents related to the top quark will definitely signal new physics beyond the SM. In this work we will discuss how an electron-positron collider can contribute to the field after the Large Hadron Collider (LHC) has collected at least 100 fb^{-1} of integrated luminosity operating at sqrt{s} = 14 TeV. |
1005.0993 | Yuji Sakai | Yuji Sakai, Takahiro Sasaki, Hiroaki Kouno and Masanobu Yahiro | Average phase factor in the PNJL model | 8 pages, 6 figures | Phys.Rev.D82:096007,2010 | 10.1103/PhysRevD.82.096007 | null | hep-ph hep-lat hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The average phase factor of the QCD determinant is evaluated at finite quark
chemical potential ({\mu}_q) with the two-flavor version of the Polyakov-loop
extended Nambu-Jona-Lasinio (PNJL) model with the scalar-type eight-quark
interaction. For {\mu}_q larger than half the pion mass at vacuum m_{\pi}, the
average phase factor is finite only when the Polyakov loop is larger than 0.5,
indicating that lattice QCD is feasible only in the deconfinement phase. A
critical endpoint (CEP) lies in the region of the zero average phase factor.
The scalar-type eight-quark interaction makes it shorter a relative distance of
the CEP to the boundary of the region. For {\mu}_q < m_{\pi}/2, the PNJL model
with dynamical mesonic fluctuations can reproduce lattice QCD data below the
critical temperature.
| [
{
"created": "Thu, 6 May 2010 13:35:10 GMT",
"version": "v1"
}
] | 2010-12-13 | [
[
"Sakai",
"Yuji",
""
],
[
"Sasaki",
"Takahiro",
""
],
[
"Kouno",
"Hiroaki",
""
],
[
"Yahiro",
"Masanobu",
""
]
] | The average phase factor of the QCD determinant is evaluated at finite quark chemical potential ({\mu}_q) with the two-flavor version of the Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model with the scalar-type eight-quark interaction. For {\mu}_q larger than half the pion mass at vacuum m_{\pi}, the average phase factor is finite only when the Polyakov loop is larger than 0.5, indicating that lattice QCD is feasible only in the deconfinement phase. A critical endpoint (CEP) lies in the region of the zero average phase factor. The scalar-type eight-quark interaction makes it shorter a relative distance of the CEP to the boundary of the region. For {\mu}_q < m_{\pi}/2, the PNJL model with dynamical mesonic fluctuations can reproduce lattice QCD data below the critical temperature. |
2207.03937 | Maxim Dvornikov | Maxim Dvornikov (IZMIRAN) | Neutrino oscillations in gravitational fields and astrophysical
applications | 3 pages in Revtex, 3 eps figures, contribution to the proceedings of
20th Lomonosov Conference on Elementary Particle Physics (August 19-25, 2021,
Moscow, Russia), to be published in Moscow University Physics Bulletin | Moscow University Physics Bulletin 77, 439-441 (2022) | 10.3103/S002713492202031X | null | hep-ph astro-ph.HE gr-qc | http://creativecommons.org/licenses/by/4.0/ | The neutrino propagation and oscillations in various gravitational fields are
studied. First, we consider the neutrino scattering off a black hole accounting
for the neutrino spin precession. Then, we study the evolution of flavor
neutrinos in stochastic gravitational waves. The astrophysical applications of
the obtained results are considered.
| [
{
"created": "Fri, 8 Jul 2022 14:43:13 GMT",
"version": "v1"
}
] | 2022-08-12 | [
[
"Dvornikov",
"Maxim",
"",
"IZMIRAN"
]
] | The neutrino propagation and oscillations in various gravitational fields are studied. First, we consider the neutrino scattering off a black hole accounting for the neutrino spin precession. Then, we study the evolution of flavor neutrinos in stochastic gravitational waves. The astrophysical applications of the obtained results are considered. |
2110.05958 | Bodo Lampe | Bodo Lampe | From Neutrino Masses to the Full Size of the Universe | Talk given at the Sixteenth Marcel Grossmann Meeting (MG16), Rome,
July 5-10, 2021. To appear in the proceedings. Part of the presentation draws
significantly from the original work arXiv:2103.09622 | null | null | null | hep-ph | http://creativecommons.org/licenses/by-nc-nd/4.0/ | Our universe is a 3-dimensional elastic substrate which once has condensed
and now is expanding within some higher dimensional space. The elastic
substrate is built from tiny invisible constituents, called tetrons, with bond
length about the Planck length and binding energy the Planck energy. All
ordinary matter particles are quasiparticle excitations of the tetrons gliding
on the elastic medium. Since the quasiparticles fulfill Lorentz covariant wave
equations, they perceive the universe as a 3+1 dimensional spacetime continuum
lacking a preferred rest system. Any type of mass/energy induces curvature on
the spacetime continuum as determined by the Einstein equations. The 24 known
quarks and leptons arise as eigenmode excitations of a tetrahedral fiber
structure, which is made up from 4 tetrons and extends into 3 additional
dimensions. While the laws of gravity are due to the elastic properties of the
tetron bonds, particle physics interactions take place within the fibers. I
will concentrate on three of the most intriguing features of the model: (i)
Understanding small neutrino masses from the conservation of isospin, and, more
in general, calculating the spectrum of quark and lepton masses. This is
obtained from the tetron model's interpretation of the Higgs mechanism. As a
byproduct, the connection between the large top mass and the electroweak
symmetry breaking becomes apparent. (ii) The possibility to determine the full
size of the universe from future dark energy measurements. This is obtained
from the tetron model's interpretation of the dark energy effect. (iii)
Finally, the origin of the big bang `Hubble tension' within the tetron scheme
will be elucidated, and deviations from the standard picture such as a varying
Newton constant are discussed.
| [
{
"created": "Mon, 11 Oct 2021 15:16:35 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Mar 2022 19:41:53 GMT",
"version": "v2"
},
{
"created": "Wed, 11 May 2022 21:05:55 GMT",
"version": "v3"
},
{
"created": "Wed, 19 Oct 2022 09:33:42 GMT",
"version": "v4"
}
] | 2022-10-20 | [
[
"Lampe",
"Bodo",
""
]
] | Our universe is a 3-dimensional elastic substrate which once has condensed and now is expanding within some higher dimensional space. The elastic substrate is built from tiny invisible constituents, called tetrons, with bond length about the Planck length and binding energy the Planck energy. All ordinary matter particles are quasiparticle excitations of the tetrons gliding on the elastic medium. Since the quasiparticles fulfill Lorentz covariant wave equations, they perceive the universe as a 3+1 dimensional spacetime continuum lacking a preferred rest system. Any type of mass/energy induces curvature on the spacetime continuum as determined by the Einstein equations. The 24 known quarks and leptons arise as eigenmode excitations of a tetrahedral fiber structure, which is made up from 4 tetrons and extends into 3 additional dimensions. While the laws of gravity are due to the elastic properties of the tetron bonds, particle physics interactions take place within the fibers. I will concentrate on three of the most intriguing features of the model: (i) Understanding small neutrino masses from the conservation of isospin, and, more in general, calculating the spectrum of quark and lepton masses. This is obtained from the tetron model's interpretation of the Higgs mechanism. As a byproduct, the connection between the large top mass and the electroweak symmetry breaking becomes apparent. (ii) The possibility to determine the full size of the universe from future dark energy measurements. This is obtained from the tetron model's interpretation of the dark energy effect. (iii) Finally, the origin of the big bang `Hubble tension' within the tetron scheme will be elucidated, and deviations from the standard picture such as a varying Newton constant are discussed. |
hep-ph/0604004 | Nikita Agasian | N.O.Agasian and Yu.A.Simonov | New nonperturbative approach to the Debye mass in hot QCD | 14 pages, 4 figures; new figures and discussion added; to appear in
Phys.Lett.B | Phys.Lett.B639:82-87,2006 | 10.1016/j.physletb.2006.06.019 | ITEP-PH-1-2006 | hep-ph hep-lat hep-th nucl-th | null | The Debye mass m_D is computed nonperturbatively in the deconfined phase of
QCD, where chromomagnetic confinement is known to be present. The latter
defines m_D to be m_D=c_D\sqrt{\sigma_s}, where c_D \cong 2.06 and
\sigma_s=\sigma_s(T) is the spatial string tension. The resulting magnitude of
m_D(T) and temperature dependence are in good agreement with lattice
calculations. Background perturbation theory expansion for m_D(T) is discussed
in comparison to standard perturbative results and recent gauge-invariant
definitions.
| [
{
"created": "Sun, 2 Apr 2006 13:19:02 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Apr 2006 18:01:47 GMT",
"version": "v2"
},
{
"created": "Tue, 13 Jun 2006 14:32:06 GMT",
"version": "v3"
}
] | 2014-11-18 | [
[
"Agasian",
"N. O.",
""
],
[
"Simonov",
"Yu. A.",
""
]
] | The Debye mass m_D is computed nonperturbatively in the deconfined phase of QCD, where chromomagnetic confinement is known to be present. The latter defines m_D to be m_D=c_D\sqrt{\sigma_s}, where c_D \cong 2.06 and \sigma_s=\sigma_s(T) is the spatial string tension. The resulting magnitude of m_D(T) and temperature dependence are in good agreement with lattice calculations. Background perturbation theory expansion for m_D(T) is discussed in comparison to standard perturbative results and recent gauge-invariant definitions. |
hep-ph/0301043 | Jan Nemcik | J. Nemchik | Nuclear Shadowing in DIS: Numerical Solution of the Evolution Equation
for the Green Function | 21 pages including 3 figures; a small revision of the text | Phys.Rev. C68 (2003) 035206 | 10.1103/PhysRevC.68.035206 | null | hep-ph | null | Within a light-cone QCD formalism based on the Green function technique
incorporating color transparency and coherence length effects we study nuclear
shadowing in deep-inelastic scattering at moderately small Bjorken x_{Bj}.
Calculations performed so far were based only on approximations leading to an
analytical harmonic oscillatory form of the Green function. We present for the
first time an exact numerical solution of the evolution equation for the Green
function using realistic form of the dipole cross section and nuclear density
function. We compare numerical results for nuclear shadowing with previous
predictions and discuss differences.
| [
{
"created": "Wed, 8 Jan 2003 10:41:37 GMT",
"version": "v1"
},
{
"created": "Thu, 5 Jun 2003 12:44:00 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Nemchik",
"J.",
""
]
] | Within a light-cone QCD formalism based on the Green function technique incorporating color transparency and coherence length effects we study nuclear shadowing in deep-inelastic scattering at moderately small Bjorken x_{Bj}. Calculations performed so far were based only on approximations leading to an analytical harmonic oscillatory form of the Green function. We present for the first time an exact numerical solution of the evolution equation for the Green function using realistic form of the dipole cross section and nuclear density function. We compare numerical results for nuclear shadowing with previous predictions and discuss differences. |
1610.06408 | Miguel Sanchis | Miguel-Angel Sanchis-Lozano, Edward Sarkisyan-Grinbaum | A correlated-cluster model and the ridge phenomenon in hadron-hadron
collisions | 1 figure | null | 10.1016/j.physletb.2017.01.001 | IFIC/16-75, FTUV-16-1020 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A study of the near-side ridge phenomenon in hadron-hadron collisions based
on a cluster picture of multiparticle production is presented. The near-side
ridge effect is shown to have a natural explanation in this context provided
that clusters are produced in a correlated manner in the collision transverse
plane.
| [
{
"created": "Thu, 20 Oct 2016 13:36:19 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Jan 2017 09:55:02 GMT",
"version": "v2"
}
] | 2017-01-11 | [
[
"Sanchis-Lozano",
"Miguel-Angel",
""
],
[
"Sarkisyan-Grinbaum",
"Edward",
""
]
] | A study of the near-side ridge phenomenon in hadron-hadron collisions based on a cluster picture of multiparticle production is presented. The near-side ridge effect is shown to have a natural explanation in this context provided that clusters are produced in a correlated manner in the collision transverse plane. |
1101.3668 | Jo\~ao Moreira | J. Moreira, B. Hiller, A. A. Osipov and A. H. Blin | Extended Nambu--Jona-Lasinio Model with covariant regularization | 4 pages, 4 figures prepared for the proceedings of 6th International
Conference on Physics and Astrophysics of Quark Gluon Plasma (ICPAQGP 2010) | Nuclear Physics A 862-863 (2011) 344-346 | 10.1016/j.nuclphysa.2011.05.069 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Several advantages in the use of a Pauli-Villars regularization procedure in
extended Nambu--Jona-Lasinio models with Polyakov loop are discussed.
| [
{
"created": "Wed, 19 Jan 2011 11:53:33 GMT",
"version": "v1"
}
] | 2011-11-29 | [
[
"Moreira",
"J.",
""
],
[
"Hiller",
"B.",
""
],
[
"Osipov",
"A. A.",
""
],
[
"Blin",
"A. H.",
""
]
] | Several advantages in the use of a Pauli-Villars regularization procedure in extended Nambu--Jona-Lasinio models with Polyakov loop are discussed. |
2111.00329 | Sanjib Kumar Agarwalla | Sanjib Kumar Agarwalla, Sudipta Das, Alessio Giarnetti, Davide Meloni | Model-Independent Constraints on Non-Unitary Neutrino Mixing from
High-Precision Long-Baseline Experiments | 39 pages, 10 figures, 11 tables, and 2 appendices. Published in JHEP | null | 10.1007/JHEP07(2022)121 | IP/BBSR/2021-10 | hep-ph hep-ex physics.ins-det | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Our knowledge on the active 3$\nu$ mixing angles ($\theta_{12}$,
$\theta_{13}$, and $\theta_{23}$) and the CP phase $\delta_{\mathrm{CP}}$ is
becoming accurate day-by-day enabling us to test the unitarity of the leptonic
mixing matrix with utmost precision. Future high-precision long-baseline
experiments are going to play an important role in this direction. In this
work, we study the impact of possible non-unitary neutrino mixing (NUNM) in the
context of next-generation long-baseline experiments DUNE and T2HKK/JD+KD
having one detector in Japan (T2HK/JD) and a second detector in Korea (KD). We
estimate the sensitivities of these setups to place direct, model-independent,
and competitive constraints on various NUNM parameters. We demonstrate the
possible correlations between the NUNM parameters, $\theta_{23}$, and
$\delta_{\mathrm{CP}}$. Our numerical results obtained using only far detector
data and supported by simple approximate analytical expressions of the
oscillation probabilities in matter, reveal that JD+KD has better sensitivities
for $|\alpha_{21}|$ and $\alpha_{22}$ as compared to DUNE, due to its larger
statistics in the appearance channel and less systematic uncertainties in the
disappearance channel, respectively. For $|\alpha_{31}|$, $|\alpha_{32}|$, and
$\alpha_{33}$, DUNE gives better constraints as compared to JD+KD, due to its
larger matter effect and wider neutrino energy spectrum. For $\alpha_{11}$,
both DUNE and JD+KD give similar bounds. We also show how much the bounds on
the NUNM parameters can be improved by combining the prospective data from DUNE
and JD+KD setups. We find that due to zero-distance effects, the near detectors
alone can also constrain $\alpha_{11}$, $|\alpha_{21}|$, and $\alpha_{22}$ in
both these setups. Finally, we observe that the $\nu_\tau$ appearance sample in
DUNE can improve the constraints on $|\alpha_{32}|$ and $\alpha_{33}$.
| [
{
"created": "Sat, 30 Oct 2021 20:41:44 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Aug 2022 21:23:50 GMT",
"version": "v2"
}
] | 2022-08-16 | [
[
"Agarwalla",
"Sanjib Kumar",
""
],
[
"Das",
"Sudipta",
""
],
[
"Giarnetti",
"Alessio",
""
],
[
"Meloni",
"Davide",
""
]
] | Our knowledge on the active 3$\nu$ mixing angles ($\theta_{12}$, $\theta_{13}$, and $\theta_{23}$) and the CP phase $\delta_{\mathrm{CP}}$ is becoming accurate day-by-day enabling us to test the unitarity of the leptonic mixing matrix with utmost precision. Future high-precision long-baseline experiments are going to play an important role in this direction. In this work, we study the impact of possible non-unitary neutrino mixing (NUNM) in the context of next-generation long-baseline experiments DUNE and T2HKK/JD+KD having one detector in Japan (T2HK/JD) and a second detector in Korea (KD). We estimate the sensitivities of these setups to place direct, model-independent, and competitive constraints on various NUNM parameters. We demonstrate the possible correlations between the NUNM parameters, $\theta_{23}$, and $\delta_{\mathrm{CP}}$. Our numerical results obtained using only far detector data and supported by simple approximate analytical expressions of the oscillation probabilities in matter, reveal that JD+KD has better sensitivities for $|\alpha_{21}|$ and $\alpha_{22}$ as compared to DUNE, due to its larger statistics in the appearance channel and less systematic uncertainties in the disappearance channel, respectively. For $|\alpha_{31}|$, $|\alpha_{32}|$, and $\alpha_{33}$, DUNE gives better constraints as compared to JD+KD, due to its larger matter effect and wider neutrino energy spectrum. For $\alpha_{11}$, both DUNE and JD+KD give similar bounds. We also show how much the bounds on the NUNM parameters can be improved by combining the prospective data from DUNE and JD+KD setups. We find that due to zero-distance effects, the near detectors alone can also constrain $\alpha_{11}$, $|\alpha_{21}|$, and $\alpha_{22}$ in both these setups. Finally, we observe that the $\nu_\tau$ appearance sample in DUNE can improve the constraints on $|\alpha_{32}|$ and $\alpha_{33}$. |
hep-ph/0502097 | Walter Winter | Walter Winter | Probing the absolute density of the Earth's core using a vertical
neutrino beam | Second column in Table I corrected; 4 pages, 4 figures (color online) | Phys.Rev. D72 (2005) 037302 | 10.1103/PhysRevD.72.037302 | null | hep-ph physics.geo-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We demonstrate that one could measure the absolute matter density of the
Earth's core with a vertical neutrino factory baseline at the per cent level
for $\sin^2 2 \theta_{13} \gtrsim 0.01$, where we include all correlations with
the oscillation parameters in the analysis. We discuss the geographical
feasibility of such an approach, and illustrate how the results change as a
function of the detector location. We point out the complementarity to
geophysics.
| [
{
"created": "Thu, 10 Feb 2005 14:20:25 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Aug 2005 16:04:30 GMT",
"version": "v2"
},
{
"created": "Thu, 19 May 2011 14:26:43 GMT",
"version": "v3"
}
] | 2011-05-20 | [
[
"Winter",
"Walter",
""
]
] | We demonstrate that one could measure the absolute matter density of the Earth's core with a vertical neutrino factory baseline at the per cent level for $\sin^2 2 \theta_{13} \gtrsim 0.01$, where we include all correlations with the oscillation parameters in the analysis. We discuss the geographical feasibility of such an approach, and illustrate how the results change as a function of the detector location. We point out the complementarity to geophysics. |
hep-ph/9601267 | Ulf Meissner | V. Bernard, N. Kaiser and Ulf-G. Mei{\ss}ner | Improved description of threshold pion electroproduction in chiral
perturbation theory | 25 pp, LaTeX, uses epsf and elsart12.sty, 8 figures in 10 PS files | Nucl.Phys. A607 (1996) 379-401; Erratum-ibid. A633 (1998) 695-697 | 10.1016/0375-9474(96)00184-4 | CRN 96-01 and TK 96 02 | hep-ph nucl-th | null | We investigate neutral pion electroproduction off protons in the framework of
heavy baryon chiral perturbation theory. The chiral expansion of the S--wave
multipoles $E_{0+}$ and $L_{0+}$ is carried out to three orders. There appear
several undetermined low--energy constants. Three are taken from a recent study
of the new TAPS threshold $\pi^0$ photoproduction data, one is fixed from the
proton Dirac form factor and the novel S--wave constants appearing at orders
$q^4$ and $q^5$ are determined from a best fit (constrained by resonance
exchange) to the recent NIKHEF and MAMI data at photon momentum transfer
squared $k^2 = -0.1 \, \, {\rm GeV}^2$. The inclusion of a particular set of
dimension five operators is forced upon the fit by a soft--pion theorem which
severely constrains the momentum dependence of the longitudinal S--wave
multipole $L_{0+}$ at order $q^4$. We give predictions for lower photon
virtualities for the various multipoles and differential cross sections.
Further improvements are briefly touched upon.
| [
{
"created": "Mon, 15 Jan 1996 13:55:02 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Bernard",
"V.",
""
],
[
"Kaiser",
"N.",
""
],
[
"Meißner",
"Ulf-G.",
""
]
] | We investigate neutral pion electroproduction off protons in the framework of heavy baryon chiral perturbation theory. The chiral expansion of the S--wave multipoles $E_{0+}$ and $L_{0+}$ is carried out to three orders. There appear several undetermined low--energy constants. Three are taken from a recent study of the new TAPS threshold $\pi^0$ photoproduction data, one is fixed from the proton Dirac form factor and the novel S--wave constants appearing at orders $q^4$ and $q^5$ are determined from a best fit (constrained by resonance exchange) to the recent NIKHEF and MAMI data at photon momentum transfer squared $k^2 = -0.1 \, \, {\rm GeV}^2$. The inclusion of a particular set of dimension five operators is forced upon the fit by a soft--pion theorem which severely constrains the momentum dependence of the longitudinal S--wave multipole $L_{0+}$ at order $q^4$. We give predictions for lower photon virtualities for the various multipoles and differential cross sections. Further improvements are briefly touched upon. |
1811.02232 | Vladimir Galkin | R.N. Faustov, V.O. Galkin | Heavy baryon spectroscopy | 10 pages, 1 figure, talk at XXIV International Baldin Seminar on High
Energy Physics Problems, Sep 17-22, 2018, Dubna, Russia | null | 10.1051/epjconf/201920408001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Masses of heavy baryons are calculated in the relativistic quark-diquark
picture. Obtained results are in good agreement with available experimental
data including recent measurements by the LHCb Collaboration. Possible quantum
numbers of excited heavy baryon states are discussed.
| [
{
"created": "Tue, 6 Nov 2018 08:58:52 GMT",
"version": "v1"
}
] | 2019-05-01 | [
[
"Faustov",
"R. N.",
""
],
[
"Galkin",
"V. O.",
""
]
] | Masses of heavy baryons are calculated in the relativistic quark-diquark picture. Obtained results are in good agreement with available experimental data including recent measurements by the LHCb Collaboration. Possible quantum numbers of excited heavy baryon states are discussed. |
hep-ph/0111192 | Wilfried Buchmuller | W. Buchm\"uller | Physics at HERA II | 16 pages, 9 figures, presented at DIS2001, Bologna | null | 10.1142/9789812778345_0006 | DESY 01-185 | hep-ph | null | Deep inelastic electron proton scattering at HERA II will allow precise
studies of QCD and stringent tests of physics beyond the standard model. We
discuss these two aspects of DIS with emphasis on the regime of high gluon
densities at small $x$ and on scalar quark production in supersymmetric
theories with broken R-parity.
| [
{
"created": "Thu, 15 Nov 2001 17:34:07 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Buchmüller",
"W.",
""
]
] | Deep inelastic electron proton scattering at HERA II will allow precise studies of QCD and stringent tests of physics beyond the standard model. We discuss these two aspects of DIS with emphasis on the regime of high gluon densities at small $x$ and on scalar quark production in supersymmetric theories with broken R-parity. |
2101.02245 | Benjamin Fuks | Benjamin Fuks, Pyungwon Ko, Seung J. Lee (editors), Jack Y. Araz, Eric
Conte, Robin Ducrocq, Thomas Flacke, Si Hyun Jeon, Taejeong Kim, Richard
Ruiz, Dipan Sengupta (conveners), Sam Bein, Jin Choi, Luc Darm\'e, Mark D.
Goodsell, Ho Jang, Adil Jueid, Won Jun, Yechan Kang, Jeongwoo Kim, Jihun Kim,
Jinheung Kim, Jehyun Lee, Joon-Bin Lee, SooJin Lee, Taegyu Lee, Jongwon Lim,
Chih-Ting Lu, Ui Min, Malte Mrowietz, Kyungmin Park, Jae-Hyeon Park, Jiwon
Park, Jory Sonneveld and Soohyun Yun | Proceedings of the second MadAnalysis 5 workshop on LHC recasting in
Korea | 119 pages, 37 figures, 48 tables and 12 new analyses added to the
MadAnalysis 5 Public Analysis Database. More information available from
https://indico.cern.ch/event/873524/ and
http://madanalysis.irmp.ucl.ac.be/wiki/PublicAnalysisDatabase | MPLA Vol. 36, No. 01, 2102001 (2021) | 10.1142/S0217732321020016 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We document the activities performed during the second MadAnalysis 5 workshop
on LHC recasting, that was organised in KIAS (Seoul, Korea) on February 12-20,
2020. We detail the implementation of 12 new ATLAS and CMS searches in the
MadAnalysis 5 Public Analysis Database, and the associated validation
procedures. Those searches probe the production of extra gauge and
scalar/pseudoscalar bosons, supersymmetry, seesaw models and deviations from
the Standard Model in four-top production.
| [
{
"created": "Wed, 6 Jan 2021 19:46:46 GMT",
"version": "v1"
}
] | 2021-08-27 | [
[
"Fuks",
"Benjamin",
"",
"editors"
],
[
"Ko",
"Pyungwon",
"",
"editors"
],
[
"Lee",
"Seung J.",
"",
"editors"
],
[
"Araz",
"Jack Y.",
"",
"conveners"
],
[
"Conte",
"Eric",
"",
"conveners"
],
[
"Ducrocq",
"Ro... | We document the activities performed during the second MadAnalysis 5 workshop on LHC recasting, that was organised in KIAS (Seoul, Korea) on February 12-20, 2020. We detail the implementation of 12 new ATLAS and CMS searches in the MadAnalysis 5 Public Analysis Database, and the associated validation procedures. Those searches probe the production of extra gauge and scalar/pseudoscalar bosons, supersymmetry, seesaw models and deviations from the Standard Model in four-top production. |
1304.5215 | Naoki Yamatsu | Naoki Yamatsu | A Supersymmetric Grand Unified Model with Noncompact Horizontal Symmetry | 30 pages, 4 figures | null | 10.1093/ptep/ptt100 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a supersymmetric SU(5) grand unified model with a horizontal symmetry
SU(1,1), we discuss spontaneous generation of generations to produce three
chiral generations of quarks and leptons and one generation of higgses by using
one structure field with a half-integer spin of SU(1,1) and two structure
fields with integer spins. In particular, the colored higgses can disappear
without fine-tuning. The difference of the Yukawa coupling matrices between the
down-type quarks and charged leptons is discussed. We show that some special
SU(1,1) weight assignments include R-parity as a discrete subgroup, and
R-parity remains even after we take into account the SU(1,1) breaking effects
from all the VEVs of the structure and matter fields. The assignments forbid
the baryon and/or lepton number violating terms except a superpotential quartic
term including a coupling of two lepton doublets and two up-type higgses. We
discuss how to generate sizable neutrino masses. We show that the proton decay
derived from the colored higgses is highly suppressed.
| [
{
"created": "Thu, 18 Apr 2013 18:43:51 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Nov 2013 02:47:46 GMT",
"version": "v2"
}
] | 2014-05-07 | [
[
"Yamatsu",
"Naoki",
""
]
] | In a supersymmetric SU(5) grand unified model with a horizontal symmetry SU(1,1), we discuss spontaneous generation of generations to produce three chiral generations of quarks and leptons and one generation of higgses by using one structure field with a half-integer spin of SU(1,1) and two structure fields with integer spins. In particular, the colored higgses can disappear without fine-tuning. The difference of the Yukawa coupling matrices between the down-type quarks and charged leptons is discussed. We show that some special SU(1,1) weight assignments include R-parity as a discrete subgroup, and R-parity remains even after we take into account the SU(1,1) breaking effects from all the VEVs of the structure and matter fields. The assignments forbid the baryon and/or lepton number violating terms except a superpotential quartic term including a coupling of two lepton doublets and two up-type higgses. We discuss how to generate sizable neutrino masses. We show that the proton decay derived from the colored higgses is highly suppressed. |
hep-ph/0602232 | A. V. Luchinsky | V. V. Braguta, A. K. Likhoded, A. V. Luchinsky | The process $\epem\to J/ \psi X(3940)$ at $\sqrt s = 10.6$ GeV in the
framework of light cone formalism | minor changes | Phys.Rev.D74:094004,2006 | 10.1103/PhysRevD.74.094004 | null | hep-ph | null | This paper is devoted to the study of the process $\epem\to J/\psi X(3940)$
in the framework of light cone formalism. In our calculation two hypotheses
about the structure of X(3940) meson are considered: X(3940) is $3^1$S$_0$
state and X(3940) is one of $2^3$P states. The former hypothesis leads to a
good agreements with the cross section measured at the experiment. As to the
latter one, it is proposed a mechanism that allows one to understand the
suppression of 2P mesons production in hard processes.
| [
{
"created": "Sun, 26 Feb 2006 08:19:38 GMT",
"version": "v1"
},
{
"created": "Thu, 2 Nov 2006 10:57:53 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Braguta",
"V. V.",
""
],
[
"Likhoded",
"A. K.",
""
],
[
"Luchinsky",
"A. V.",
""
]
] | This paper is devoted to the study of the process $\epem\to J/\psi X(3940)$ in the framework of light cone formalism. In our calculation two hypotheses about the structure of X(3940) meson are considered: X(3940) is $3^1$S$_0$ state and X(3940) is one of $2^3$P states. The former hypothesis leads to a good agreements with the cross section measured at the experiment. As to the latter one, it is proposed a mechanism that allows one to understand the suppression of 2P mesons production in hard processes. |
1604.06677 | Rafiqul Rahaman | Rafiqul Rahaman, Ritesh K. Singh | On polarization parameters of spin-$1$ particles and anomalous couplings
in $e^+e^-\to ZZ/Z\gamma$ | 35+1 pages, 15 figures, 10 tables; v2: some changes in abstract,
introduction and discussions, version accepted for publication in EPJC | Eur.Phys.J. C76 (2016) no.10, 539 | 10.1140/epjc/s10052-016-4374-4 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the anomalous trilinear gauge couplings of $Z$ and $\gamma$ using a
complete set of polarization asymmetries for the $Z$ boson in $e^+e^-\to
ZZ/Z\gamma$ processes with unpolarized initial beams. We use these polarization
asymmetries, along with the cross section, to obtain a simultaneous limit on
all the anomalous couplings using the Markov-Chain--Monte-Carlo (MCMC) method.
For an $e^+e^-$ collider running at $500$ GeV center-of-mass energy and $100$
fb$^{-1}$ of integrated luminosity the simultaneous limits on the anomalous
couplings are $1\sim3\times 10^{-3}$.
| [
{
"created": "Fri, 22 Apr 2016 14:16:25 GMT",
"version": "v1"
},
{
"created": "Sun, 18 Sep 2016 04:12:49 GMT",
"version": "v2"
},
{
"created": "Sat, 27 Apr 2019 16:11:38 GMT",
"version": "v3"
}
] | 2019-04-30 | [
[
"Rahaman",
"Rafiqul",
""
],
[
"Singh",
"Ritesh K.",
""
]
] | We study the anomalous trilinear gauge couplings of $Z$ and $\gamma$ using a complete set of polarization asymmetries for the $Z$ boson in $e^+e^-\to ZZ/Z\gamma$ processes with unpolarized initial beams. We use these polarization asymmetries, along with the cross section, to obtain a simultaneous limit on all the anomalous couplings using the Markov-Chain--Monte-Carlo (MCMC) method. For an $e^+e^-$ collider running at $500$ GeV center-of-mass energy and $100$ fb$^{-1}$ of integrated luminosity the simultaneous limits on the anomalous couplings are $1\sim3\times 10^{-3}$. |
hep-ph/9808285 | Kevin B. Sprague | Victor Elias and Kevin Sprague | Fermion-Antifermion Condensate Contribution to the Anomalous Magnetic
Moment of a Fundamental Dirac Fermion | 39 pages, 4 figures, accepted for publication in the International
Journal of Theoretical Physics (November issue) | Int.J.Theor.Phys. 37 (1998) 2767-2789 | null | null | hep-ph | null | We consider the contribution of fermion-antifermion condensates to the
anomalous magnetic moment of a fermion in a vacuum in which such condensates
exist. The real part of the condensate contribution to the anomalous magnetic
moment is shown to be zero. A nonzero imaginary part is obtained below the
kinematic threshold for intermediate fermion-antifermion pairs. The calculation
is shown to be gauge-parameter independent provided a single fermion mass
characterizes both the fermion propagator and condensate-sensitive
contributions, suggestive of a dynamically-generated fermion mass. The nonzero
imaginary part is then argued to correspond to the kinematic production of the
intermediate-state Goldstone bosons anticipated from a chiral-noninvariant
vacuum. Finally, speculations are presented concerning the applicability of
these results to quark electromagnetic properties.
| [
{
"created": "Mon, 10 Aug 1998 18:29:10 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Elias",
"Victor",
""
],
[
"Sprague",
"Kevin",
""
]
] | We consider the contribution of fermion-antifermion condensates to the anomalous magnetic moment of a fermion in a vacuum in which such condensates exist. The real part of the condensate contribution to the anomalous magnetic moment is shown to be zero. A nonzero imaginary part is obtained below the kinematic threshold for intermediate fermion-antifermion pairs. The calculation is shown to be gauge-parameter independent provided a single fermion mass characterizes both the fermion propagator and condensate-sensitive contributions, suggestive of a dynamically-generated fermion mass. The nonzero imaginary part is then argued to correspond to the kinematic production of the intermediate-state Goldstone bosons anticipated from a chiral-noninvariant vacuum. Finally, speculations are presented concerning the applicability of these results to quark electromagnetic properties. |
1710.08431 | Ryan Plestid | Gabriel Magill, Ryan Plestid | Probing new charged scalars with neutrino trident production | 6 pages body, 4 pages appendix, 2 pages references | Phys. Rev. D 97, 055003 (2018) | 10.1103/PhysRevD.97.055003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the possibility of using neutrino trident production to probe
leptophilic charged scalars at future high intensity neutrino experiments. We
show that under specific assumptions, this production process can provide
competitive sensitivity for generic charged scalars as compared to common
existing bounds. We also investigate how the recently proposed mixed-flavour
production - where the two oppositely charged leptons in the final state need
not be muon flavoured - can give a 20-50% increase in sensitivity for certain
configurations of new physics couplings as compared to traditional trident
modes. We then categorize all renormalizable leptophilic scalar extensions
based on their representation under $SU(2)\times U(1)$, and discuss the Higgs
triplet and Zee-Babu models as explicit UV realizations. We find that the
inclusion of additional doubly charged scalars and the need to reproduce
neutrino masses make trident production uncompetitive with current bounds for
these specific UV completions. Our work represents the first application of
neutrino trident production to study charged scalars, and of mixed-flavour
final states to study physics beyond the Standard Model.
| [
{
"created": "Mon, 23 Oct 2017 18:00:08 GMT",
"version": "v1"
}
] | 2018-03-14 | [
[
"Magill",
"Gabriel",
""
],
[
"Plestid",
"Ryan",
""
]
] | We investigate the possibility of using neutrino trident production to probe leptophilic charged scalars at future high intensity neutrino experiments. We show that under specific assumptions, this production process can provide competitive sensitivity for generic charged scalars as compared to common existing bounds. We also investigate how the recently proposed mixed-flavour production - where the two oppositely charged leptons in the final state need not be muon flavoured - can give a 20-50% increase in sensitivity for certain configurations of new physics couplings as compared to traditional trident modes. We then categorize all renormalizable leptophilic scalar extensions based on their representation under $SU(2)\times U(1)$, and discuss the Higgs triplet and Zee-Babu models as explicit UV realizations. We find that the inclusion of additional doubly charged scalars and the need to reproduce neutrino masses make trident production uncompetitive with current bounds for these specific UV completions. Our work represents the first application of neutrino trident production to study charged scalars, and of mixed-flavour final states to study physics beyond the Standard Model. |
2209.10601 | Matthias Lutz F.M. | Matthias F.M. Lutz, Xiao-Yu Guo, Yonggoo Heo and C.L. Korpa | Coupled-channel dynamics with chiral long-range forces in the open-charm
sector of QCD | 73 pages, 8 figures, 28 tables, the revised manuscript includes a
table with the pole masses of the 0^+ resonances | null | 10.1103/PhysRevD.106.114038 | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform an analysis of Lattice QCD data in the open-charm sector based on
the chiral SU(3) Lagrangian. The low-energy constants are adjusted to recover
the open-charm meson masses on Lattice QCD ensembles from HPQCD, ETMC and HSC
with pion and kaon masses smaller than 550 MeV. A significant set of low-energy
parameters is obtainable only if the most recent information from HSC on
scattering observables is included in our global fit. For the first time our
analysis considers the effect of left-hand cuts as developed in terms of a
generalized potential approach (GPA) previously by one of the authors. Here we
use coupled-channel interaction terms at the one-loop level. The elastic s-wave
and p-wave $D\,\pi$, $D K $ and $D \bar K $ scattering phase shifts on
ensembles with nominal pion masses of about 239 MeV and 391 MeV are reproduced
faithfully. Based on such low-energy parameters we predict s- and p-wave phase
shifts and inelasticities at physical quark masses, where the statistical
uncertainties in the phase shifts are smaller than 1 degree always. Most
striking would be the exotic s-wave $D_s \pi$ channel, for which we predict a
resonance state at about 2.287 GeV where the phase shift passes through 90
degrees.
| [
{
"created": "Wed, 21 Sep 2022 18:53:19 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Nov 2022 16:03:06 GMT",
"version": "v2"
}
] | 2023-01-11 | [
[
"Lutz",
"Matthias F. M.",
""
],
[
"Guo",
"Xiao-Yu",
""
],
[
"Heo",
"Yonggoo",
""
],
[
"Korpa",
"C. L.",
""
]
] | We perform an analysis of Lattice QCD data in the open-charm sector based on the chiral SU(3) Lagrangian. The low-energy constants are adjusted to recover the open-charm meson masses on Lattice QCD ensembles from HPQCD, ETMC and HSC with pion and kaon masses smaller than 550 MeV. A significant set of low-energy parameters is obtainable only if the most recent information from HSC on scattering observables is included in our global fit. For the first time our analysis considers the effect of left-hand cuts as developed in terms of a generalized potential approach (GPA) previously by one of the authors. Here we use coupled-channel interaction terms at the one-loop level. The elastic s-wave and p-wave $D\,\pi$, $D K $ and $D \bar K $ scattering phase shifts on ensembles with nominal pion masses of about 239 MeV and 391 MeV are reproduced faithfully. Based on such low-energy parameters we predict s- and p-wave phase shifts and inelasticities at physical quark masses, where the statistical uncertainties in the phase shifts are smaller than 1 degree always. Most striking would be the exotic s-wave $D_s \pi$ channel, for which we predict a resonance state at about 2.287 GeV where the phase shift passes through 90 degrees. |
1704.05066 | Jesse Thaler | Andrew Larkoski, Simone Marzani, Jesse Thaler, Aashish Tripathee, Wei
Xue | Exposing the QCD Splitting Function with CMS Open Data | 7 pages, 5 figures; v2: references updated and figure formatting
improved; v3: approximate version to appear in PRL | Phys. Rev. Lett. 119, 132003 (2017) | 10.1103/PhysRevLett.119.132003 | MIT-CTP 4891 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The splitting function is a universal property of quantum chromodynamics
(QCD) which describes how energy is shared between partons. Despite its
ubiquitous appearance in many QCD calculations, the splitting function cannot
be measured directly since it always appears multiplied by a collinear
singularity factor. Recently, however, a new jet substructure observable was
introduced which asymptotes to the splitting function for sufficiently high jet
energies. This provides a way to expose the splitting function through jet
substructure measurements at the Large Hadron Collider. In this letter, we use
public data released by the CMS experiment to study the 2-prong substructure of
jets and test the 1 -> 2 splitting function of QCD. To our knowledge, this is
the first ever physics analysis based on the CMS Open Data.
| [
{
"created": "Mon, 17 Apr 2017 18:00:00 GMT",
"version": "v1"
},
{
"created": "Mon, 8 May 2017 01:06:10 GMT",
"version": "v2"
},
{
"created": "Mon, 25 Sep 2017 00:26:43 GMT",
"version": "v3"
}
] | 2017-09-29 | [
[
"Larkoski",
"Andrew",
""
],
[
"Marzani",
"Simone",
""
],
[
"Thaler",
"Jesse",
""
],
[
"Tripathee",
"Aashish",
""
],
[
"Xue",
"Wei",
""
]
] | The splitting function is a universal property of quantum chromodynamics (QCD) which describes how energy is shared between partons. Despite its ubiquitous appearance in many QCD calculations, the splitting function cannot be measured directly since it always appears multiplied by a collinear singularity factor. Recently, however, a new jet substructure observable was introduced which asymptotes to the splitting function for sufficiently high jet energies. This provides a way to expose the splitting function through jet substructure measurements at the Large Hadron Collider. In this letter, we use public data released by the CMS experiment to study the 2-prong substructure of jets and test the 1 -> 2 splitting function of QCD. To our knowledge, this is the first ever physics analysis based on the CMS Open Data. |
1106.1334 | Werner Rodejohann | Werner Rodejohann | Neutrino-less Double Beta Decay and Particle Physics | 96 pages, 38 figures. Published version | Int.J.Mod.Phys. E20, 1833-1930 (2011) | 10.1142/S0218301311020186 | null | hep-ph astro-ph.CO hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review the particle physics aspects of neutrino-less double beta decay.
This process can be mediated by light massive Majorana neutrinos (standard
interpretation) or by something else (non-standard interpretations). The
physics potential of both interpretations is summarized and the consequences of
future measurements or improved limits on the half-life of neutrino-less double
beta decay are discussed. We try to cover all proposed alternative realizations
of the decay, including light sterile neutrinos, supersymmetric or left-right
symmetric theories, Majorons, and other exotic possibilities. Ways to
distinguish the mechanisms from one another are discussed. Experimental and
nuclear physics aspects are also briefly touched, alternative processes to
double beta decay are discussed, and an extensive list of references is
provided.
| [
{
"created": "Tue, 7 Jun 2011 12:49:02 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Jun 2011 08:01:56 GMT",
"version": "v2"
},
{
"created": "Mon, 17 Oct 2011 09:30:38 GMT",
"version": "v3"
}
] | 2011-10-18 | [
[
"Rodejohann",
"Werner",
""
]
] | We review the particle physics aspects of neutrino-less double beta decay. This process can be mediated by light massive Majorana neutrinos (standard interpretation) or by something else (non-standard interpretations). The physics potential of both interpretations is summarized and the consequences of future measurements or improved limits on the half-life of neutrino-less double beta decay are discussed. We try to cover all proposed alternative realizations of the decay, including light sterile neutrinos, supersymmetric or left-right symmetric theories, Majorons, and other exotic possibilities. Ways to distinguish the mechanisms from one another are discussed. Experimental and nuclear physics aspects are also briefly touched, alternative processes to double beta decay are discussed, and an extensive list of references is provided. |
2312.12984 | Alberto Garcia Martin-Caro | Alberto Garc\'ia Mart\'in-Caro, Miguel Huidobro, Yoshitaka Hatta | Nuclear mass radius and pressure in the Skyrme model | 10 pages, 4 figures. 2 figures changed, 1 figure added for clarity.
Other minor changes include an improved accuracy in numerical solutions, and
addition of several references | null | null | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | We compute the mass radius, scalar radius, tensor radius, baryon number
radius and mechanical radius of nuclei with baryon number
$B=1,2,3,4,5,6,7,8,32,108$ in the Skyrme model. The relations between these
radii and the nuclear gravitational form factors are investigated. We also
compute the `pressure' distribution and find that it is negative in the core
region for all the nuclei with $B>1$. This suggests that the way mechanical
stability is achieved in nuclei is qualitatively different than in the nucleon.
| [
{
"created": "Wed, 20 Dec 2023 12:43:42 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Apr 2024 15:41:50 GMT",
"version": "v2"
}
] | 2024-04-24 | [
[
"Martín-Caro",
"Alberto García",
""
],
[
"Huidobro",
"Miguel",
""
],
[
"Hatta",
"Yoshitaka",
""
]
] | We compute the mass radius, scalar radius, tensor radius, baryon number radius and mechanical radius of nuclei with baryon number $B=1,2,3,4,5,6,7,8,32,108$ in the Skyrme model. The relations between these radii and the nuclear gravitational form factors are investigated. We also compute the `pressure' distribution and find that it is negative in the core region for all the nuclei with $B>1$. This suggests that the way mechanical stability is achieved in nuclei is qualitatively different than in the nucleon. |
1612.03438 | Stephan Narison | R.M Albuquerque (UERJ-Rio de Janeiro, BR), S. Narison
(LUPM-Montpellier, FR), F. Fanomezana, A. Rabemananjara, D. Rabetiarivony, G.
Randriamanatrika (iHEPMAD-Antananarivo, MG) | Heavy-Light Exotics from QCD Laplace Sum Rules at N2LO in the chiral
limit | Talk given at 19th International Conference in Quantum Chromodynamics
(QCD 16, 4-8 july 2016, Montpellier - FR) and at the 8th International
Conference in High-Energy Physics (HEPMAD16-15th anniversary, 13-18th october
2016, Antananarivo, MG), 9 pages, 9 figures, 8 tables. To appear in Nucl. and
Part. Phys. Proceedings (Elsevier) and in SLAC-Econf (Stanford Univ.) | null | null | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | These talks review and summarize our results in [1,2] on $XYZ$-like spectra
obtained from QCD Laplace Sum Rules in the chiral limit at next-to-next-leading
order (N2LO) of perturbation theory (PT) and including leading order (LO)
contributions of dimensions $d\leq 6-8$ non-perturbative condensates. We
conclude that the observed $XZ$ states are good candidates for $1^{+}$ and
$0^+$ molecules or / and four-quark states while the predictions for $1^-$ and
$0^-$ states are about 1.5 GeV above the $Y_{c,b}$ experimental candidates and
hadronic thresholds. We (numerically) find that these exotic molecules couple
weakly to the corresponding interpolating currents than ordinary $D,B$
heavy-light mesons while we observe that these couplings decrease faster
[$1/m_b^{3/2}$ (resp. $1/m_b$) for the $1^+,0^+$ (resp. $1^-,0^-)$ states] than
$1/m_b^{1/2}$. Our results do not also confirm the existence of the $X(5568)$
state in agreement with LHCb findings.
| [
{
"created": "Sun, 11 Dec 2016 17:08:22 GMT",
"version": "v1"
}
] | 2016-12-13 | [
[
"Albuquerque",
"R. M",
"",
"UERJ-Rio de Janeiro, BR"
],
[
"Narison",
"S.",
"",
"LUPM-Montpellier, FR"
],
[
"Fanomezana",
"F.",
"",
"iHEPMAD-Antananarivo, MG"
],
[
"Rabemananjara",
"A.",
"",
"iHEPMAD-Antananarivo, MG"
],
[
"Rabetia... | These talks review and summarize our results in [1,2] on $XYZ$-like spectra obtained from QCD Laplace Sum Rules in the chiral limit at next-to-next-leading order (N2LO) of perturbation theory (PT) and including leading order (LO) contributions of dimensions $d\leq 6-8$ non-perturbative condensates. We conclude that the observed $XZ$ states are good candidates for $1^{+}$ and $0^+$ molecules or / and four-quark states while the predictions for $1^-$ and $0^-$ states are about 1.5 GeV above the $Y_{c,b}$ experimental candidates and hadronic thresholds. We (numerically) find that these exotic molecules couple weakly to the corresponding interpolating currents than ordinary $D,B$ heavy-light mesons while we observe that these couplings decrease faster [$1/m_b^{3/2}$ (resp. $1/m_b$) for the $1^+,0^+$ (resp. $1^-,0^-)$ states] than $1/m_b^{1/2}$. Our results do not also confirm the existence of the $X(5568)$ state in agreement with LHCb findings. |
hep-ph/9911401 | Covi Laura | Laura Covi | New developments in inflationary models | 13 pages, 4 figures, to appear in the Proceedings of the Conference
"Beyond the Desert '99", Tegernsee, Germany, 6-12 June 1999 | null | null | DESY 99-172 | hep-ph | null | We study models of inflation where the inflaton corresponds to a flat
direction in field space and its mass term is generated by gravity mediated
soft supersymmetry breaking at high scale. Assuming the inflaton to have non
negligible couplings to other fields, its mass runs with scale and can reach
the small value required by slow roll inflation at a lower scale, even if its
initial value is too large. Slow roll inflation can therefore take place in
such a regime, as long as the mass remains small, with a spectral index that is
then scale dependent. We explore the parameter space of this kind of models to
find the region compatible with the present observations.
| [
{
"created": "Thu, 18 Nov 1999 16:03:43 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Covi",
"Laura",
""
]
] | We study models of inflation where the inflaton corresponds to a flat direction in field space and its mass term is generated by gravity mediated soft supersymmetry breaking at high scale. Assuming the inflaton to have non negligible couplings to other fields, its mass runs with scale and can reach the small value required by slow roll inflation at a lower scale, even if its initial value is too large. Slow roll inflation can therefore take place in such a regime, as long as the mass remains small, with a spectral index that is then scale dependent. We explore the parameter space of this kind of models to find the region compatible with the present observations. |
hep-ph/9705438 | U. Meissner | V. Bernard, A.H. Blin, B. Hiller, Yu.P. Ivanov, A.A. Osipov, Ulf-G.
Mei{\ss}ner | Quark-antiquark resonances in the NJL model | 15 pp, LaTeX file, 4 figures (uses epsf) | Phys.Lett. B409 (1997) 483-490 | 10.1016/S0370-2693(97)00930-1 | KFA-IKP(TH)-1997-10, LPT 97-05 and Coimbra University 260597 | hep-ph nucl-th | null | The problem of the $\rho$ meson resonance solution in the extended NJL model
is studied. It has been shown previously that the solution for the $\rho$ meson
changes smoothly from a bound state to a "virtual state" when the vector
channel attraction becomes too weak to support bound state solutions. We have
found that together with these solutions a separate resonance branch appears
which is not connected smoothly with the bound state solutions. At small values
of constituent quark mass, $m\sim 200$ MeV, it corresponds to the physical
vector meson resonance solution in the quark-continuum region. The $a_1$ and
$\sigma$ resonances are also discussed.
| [
{
"created": "Tue, 27 May 1997 15:05:39 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Bernard",
"V.",
""
],
[
"Blin",
"A. H.",
""
],
[
"Hiller",
"B.",
""
],
[
"Ivanov",
"Yu. P.",
""
],
[
"Osipov",
"A. A.",
""
],
[
"Meißner",
"Ulf-G.",
""
]
] | The problem of the $\rho$ meson resonance solution in the extended NJL model is studied. It has been shown previously that the solution for the $\rho$ meson changes smoothly from a bound state to a "virtual state" when the vector channel attraction becomes too weak to support bound state solutions. We have found that together with these solutions a separate resonance branch appears which is not connected smoothly with the bound state solutions. At small values of constituent quark mass, $m\sim 200$ MeV, it corresponds to the physical vector meson resonance solution in the quark-continuum region. The $a_1$ and $\sigma$ resonances are also discussed. |
hep-ph/0102318 | Sven Heinemeyer | S. Heinemeyer | Two-loop Calculations in the MSSM with FeynArts | 4 pages, 1 figure. Updated version of a talk given at the ACAT2000,
Fermilab, Oct. 2000 | null | 10.1063/1.1405305 | BNL-HET-00/46 | hep-ph | null | Recent electroweak two-loop corrections in the Minimal Supersymmetric
Standard Model (MSSM) are reviewed. They have been obtained with the help of
the programs FeynArts and TwoCalc, making use of the recently completed MSSM
model file for FeynArts. Short examples of how to use the two codes together
with the analytic result for the O(Gf^2 m_t^4) corrections to the
$\rho$-parameter in the MSSM are presented.
| [
{
"created": "Mon, 26 Feb 2001 16:33:42 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Heinemeyer",
"S.",
""
]
] | Recent electroweak two-loop corrections in the Minimal Supersymmetric Standard Model (MSSM) are reviewed. They have been obtained with the help of the programs FeynArts and TwoCalc, making use of the recently completed MSSM model file for FeynArts. Short examples of how to use the two codes together with the analytic result for the O(Gf^2 m_t^4) corrections to the $\rho$-parameter in the MSSM are presented. |
hep-ph/0608263 | Zhi-Gang Wang | Zhi-Gang Wang (NCEPU, Baoding), Shao-Long Wan | Analysis of the X(1576) as a tetraquark state with the QCD sum rules | 6 pages, 1 figure, second version, typos corrected | Chin.Phys.Lett. 23 (2006) 3208-3210 | 10.1088/0256-307X/23/12/024 | null | hep-ph | null | In this letter, we take the point of view that the X(1576) be tetraquark
state which consists of a scalar-diquark and an anti-scalar-diquark in relative
$P$-wave, and calculate its mass in the framework of the QCD sum rules
approach. The numerical value of the mass $m_X=(1.66\pm 0.14) GeV$ is
consistent with the experimental data, there may be some tetraquark component
in the vector meson X(1576).
| [
{
"created": "Wed, 23 Aug 2006 13:06:36 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Oct 2006 12:29:56 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Wang",
"Zhi-Gang",
"",
"NCEPU, Baoding"
],
[
"Wan",
"Shao-Long",
""
]
] | In this letter, we take the point of view that the X(1576) be tetraquark state which consists of a scalar-diquark and an anti-scalar-diquark in relative $P$-wave, and calculate its mass in the framework of the QCD sum rules approach. The numerical value of the mass $m_X=(1.66\pm 0.14) GeV$ is consistent with the experimental data, there may be some tetraquark component in the vector meson X(1576). |
hep-ph/0406222 | Daniel Maitre | T.Gehrmann, D.Maitre, D.Wyler | Spin Asymmetries in Squark and Gluino Production at Polarized Hadron
Colliders | 25 pages, LaTeX, typos corrected | Nucl.Phys. B703 (2004) 147-176 | 10.1016/j.nuclphysb.2004.10.013 | ZU-TH 10/04 | hep-ph | null | We study the production cross sections for squarks and gluinos in collision
of longitudinally polarized hadrons. The corresponding polarized partonic cross
sections are computed in leading order supersymmetric QCD. The resulting
asymmetries are evaluated for the polarized proton collider RHIC, as well as
for hypothetical polarized options of the Tevatron and the LHC. These
asymmetries turn out to be sizable over a wide range of supersymmetric particle
masses, thus potentially opening a window to detailed sparticle spectroscopy at
future polarized hadron colliders.
| [
{
"created": "Mon, 21 Jun 2004 13:32:37 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Jul 2004 17:58:25 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Aug 2004 11:27:59 GMT",
"version": "v3"
},
{
"created": "Tue, 14 Sep 2004 10:15:41 GMT",
"version": "v4"
},
{
"c... | 2009-11-10 | [
[
"Gehrmann",
"T.",
""
],
[
"Maitre",
"D.",
""
],
[
"Wyler",
"D.",
""
]
] | We study the production cross sections for squarks and gluinos in collision of longitudinally polarized hadrons. The corresponding polarized partonic cross sections are computed in leading order supersymmetric QCD. The resulting asymmetries are evaluated for the polarized proton collider RHIC, as well as for hypothetical polarized options of the Tevatron and the LHC. These asymmetries turn out to be sizable over a wide range of supersymmetric particle masses, thus potentially opening a window to detailed sparticle spectroscopy at future polarized hadron colliders. |
hep-ph/0701130 | Sergey Kiselev | S.M. Kiselev | Direct Photons in Ion Collisions at FAIR Energies | 7 pages,5 figures,Talk at Baldin ISHEPP XVIII, Dubna, 25 - 30
September 2006 | null | null | null | hep-ph | null | Estimations of prompt photon production at FAIR (Facility for Antiproton and
Ion Research) energies using the extrapolation of existing data are presented.
About $10^{-4}$ prompt $\gamma$ with $p_{t}>$2 GeV/c per Au+Au central event at
25 AGeV are expected. With the planed beam intensity $10^{9}/s$, 1% interaction
rate and 10% centrality, at CBM (Compressed Baryonic Matter) experiment one can
expect prompt $\gamma$ rate ~100/s.
Predictions for direct photons by some generators (PYTHIA, UrQMD, RQMD, HSD,
HIJING) are analyzed. One of the main sources of direct photons (due to meson
scatterings $\pi\rho\to\pi\gamma, \pi\pi\to\rho\gamma$) is not implemented in
the heavy-ion generators. Corresponding cross-sections for this source have
been prepared for implementation into the HSD code.
Main experimental methods to study direct photons (subtraction method,
momentum correlations method and internal conversion method) are shortly
reviewed. High intensity beam, good tracking and good $e^{\pm}$ particle
identification of the CBM detector favor to measure direct photons by all the
methods.
| [
{
"created": "Wed, 17 Jan 2007 09:17:55 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kiselev",
"S. M.",
""
]
] | Estimations of prompt photon production at FAIR (Facility for Antiproton and Ion Research) energies using the extrapolation of existing data are presented. About $10^{-4}$ prompt $\gamma$ with $p_{t}>$2 GeV/c per Au+Au central event at 25 AGeV are expected. With the planed beam intensity $10^{9}/s$, 1% interaction rate and 10% centrality, at CBM (Compressed Baryonic Matter) experiment one can expect prompt $\gamma$ rate ~100/s. Predictions for direct photons by some generators (PYTHIA, UrQMD, RQMD, HSD, HIJING) are analyzed. One of the main sources of direct photons (due to meson scatterings $\pi\rho\to\pi\gamma, \pi\pi\to\rho\gamma$) is not implemented in the heavy-ion generators. Corresponding cross-sections for this source have been prepared for implementation into the HSD code. Main experimental methods to study direct photons (subtraction method, momentum correlations method and internal conversion method) are shortly reviewed. High intensity beam, good tracking and good $e^{\pm}$ particle identification of the CBM detector favor to measure direct photons by all the methods. |
1206.6313 | Teresa F. Carames | Teresa F. Caram\'es, Alfredo Valcarce and Javier Vijande | Hunting exotics | 5 pages, 1 figure. Proceedings of Science, QNP 2012 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we study the $QQ\bar{n}\bar{n}$ systems from both four--quark
and meson--meson molecule formalisms, arriving to consistent conclusions when
the proper bases are chosen. These states are interesting as they are thought
to be found in experiments soon at LHC or RHIC. Such a source of experimental
information will significantly improve our current understanding of charm
spectroscopy.
| [
{
"created": "Wed, 27 Jun 2012 15:35:48 GMT",
"version": "v1"
}
] | 2012-06-28 | [
[
"Caramés",
"Teresa F.",
""
],
[
"Valcarce",
"Alfredo",
""
],
[
"Vijande",
"Javier",
""
]
] | In this work we study the $QQ\bar{n}\bar{n}$ systems from both four--quark and meson--meson molecule formalisms, arriving to consistent conclusions when the proper bases are chosen. These states are interesting as they are thought to be found in experiments soon at LHC or RHIC. Such a source of experimental information will significantly improve our current understanding of charm spectroscopy. |
2406.14202 | Shahnaz Taghiyeva | Mamedov Shahin and Taghiyeva Shahnaz | {\pi} Meson-Octet Baryon Coupling Constant Obtained by Hard-Wall AdS/QCD
Model | 1 table | Russian Physics Journal 67, no. 5 (2024): 660-666. Russian Physics
Journal, Volume 67, Issue 5, p.660-666 | 10.1007/s11182-024-03164-7 | EFI-94-11 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The paper studies a strong coupling constant between {\pi} meson and octet
baryon using the hard-wall AdS/QCD model, which considers SU(3)f
symmetry-breaking effects. Briefly mentioned are profile functions for
pseudoscalar meson and baryon fields. The obtained baryon coupling constants
are in agreement with those obtained in theoretical calculations.
| [
{
"created": "Thu, 20 Jun 2024 11:20:41 GMT",
"version": "v1"
}
] | 2024-06-21 | [
[
"Shahin",
"Mamedov",
""
],
[
"Shahnaz",
"Taghiyeva",
""
]
] | The paper studies a strong coupling constant between {\pi} meson and octet baryon using the hard-wall AdS/QCD model, which considers SU(3)f symmetry-breaking effects. Briefly mentioned are profile functions for pseudoscalar meson and baryon fields. The obtained baryon coupling constants are in agreement with those obtained in theoretical calculations. |
1503.05437 | Alexander Prygarin | Sergey Bondarenko and Alex Prygarin | On the Analytic Solution of the Balitsky-Kovchegov Evolution Equation | 8 pages | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The study presents an analytic solution of the Balitsky-Kovchegov~(BK)
equation in a particular kinematics. The solution is written in the momentum
space and based on the eigenfunctions of the truncated
Balitsky-Fadin-Kuraev-Lipatov~(BFKL) equation in the gauge adjoint
representation, which was used for calculation of the Regge~(Mandelstam) cut
contribution to the planar helicity amplitudes. We introduce an eigenfunction
of the singlet BFKL equation constructed of the adjoint eigenfunction
multiplied by a factor, which restores the dual conformal symmetry present in
the adjoint and broken in the singlet BFKL equations.
The proposed analytic BK solution correctly reproduces the initial condition
and the high energy asymptotics of the scattering amplitude.
| [
{
"created": "Wed, 18 Mar 2015 14:51:49 GMT",
"version": "v1"
},
{
"created": "Thu, 7 May 2015 15:18:28 GMT",
"version": "v2"
}
] | 2015-05-08 | [
[
"Bondarenko",
"Sergey",
""
],
[
"Prygarin",
"Alex",
""
]
] | The study presents an analytic solution of the Balitsky-Kovchegov~(BK) equation in a particular kinematics. The solution is written in the momentum space and based on the eigenfunctions of the truncated Balitsky-Fadin-Kuraev-Lipatov~(BFKL) equation in the gauge adjoint representation, which was used for calculation of the Regge~(Mandelstam) cut contribution to the planar helicity amplitudes. We introduce an eigenfunction of the singlet BFKL equation constructed of the adjoint eigenfunction multiplied by a factor, which restores the dual conformal symmetry present in the adjoint and broken in the singlet BFKL equations. The proposed analytic BK solution correctly reproduces the initial condition and the high energy asymptotics of the scattering amplitude. |
1510.02411 | Artem Lipatov | S.P. Baranov, A.V. Lipatov, N.P. Zotov | Prompt charmonia production and polarization at LHC in the NRQCD with
kt-factorization. Part II: $\chi_c$ mesons | 11 pages, 3 figures | Phys. Rev. D 93, 094012 (2016) | 10.1103/PhysRevD.93.094012 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of kt-factorization approach,the production of prompt
$\chi_c$ mesons in pp collisions at the LHC energies is studied. Our
consideration is based on the off-shell amplitudes for hard partonic
subprocesses $g^*g^*\to\chi_{cJ}$ and non-relativistic QCD formalism for bound
states. The transverse momentum dependent (unintegrated) gluon densities in a
proton were derived from Ciafaloni-Catani-Fiorani-Marchesini evolution equation
or, alternatively, were chosen in accordance with Kimber-Martin-Ryskin
prescription. Taking into account both color singlet and color octet
contributions, we deduce the corresponding non-perturbative long-distance
matrix elements from the fits to the latest ATLAS data on $\chi_{c1}$ and
$\chi_{c2}$ transverse momentum distributions at $\sqrt s = 7$ TeV. We find
that these distributions at small and moderate pt are formed mainly by the
color singlet components. We successfully described the data on the
differential cross sections and relative production rates
$\sigma(\chi_{c2})/\sigma(\chi_{c1})$ presented by the ATLAS, CMS and LHCb
Collaborations. We find that the fit points to unequal wave functions of
$\chi_{c1}$ and $\chi_{c2}$ states.
| [
{
"created": "Thu, 8 Oct 2015 17:23:58 GMT",
"version": "v1"
}
] | 2016-05-25 | [
[
"Baranov",
"S. P.",
""
],
[
"Lipatov",
"A. V.",
""
],
[
"Zotov",
"N. P.",
""
]
] | In the framework of kt-factorization approach,the production of prompt $\chi_c$ mesons in pp collisions at the LHC energies is studied. Our consideration is based on the off-shell amplitudes for hard partonic subprocesses $g^*g^*\to\chi_{cJ}$ and non-relativistic QCD formalism for bound states. The transverse momentum dependent (unintegrated) gluon densities in a proton were derived from Ciafaloni-Catani-Fiorani-Marchesini evolution equation or, alternatively, were chosen in accordance with Kimber-Martin-Ryskin prescription. Taking into account both color singlet and color octet contributions, we deduce the corresponding non-perturbative long-distance matrix elements from the fits to the latest ATLAS data on $\chi_{c1}$ and $\chi_{c2}$ transverse momentum distributions at $\sqrt s = 7$ TeV. We find that these distributions at small and moderate pt are formed mainly by the color singlet components. We successfully described the data on the differential cross sections and relative production rates $\sigma(\chi_{c2})/\sigma(\chi_{c1})$ presented by the ATLAS, CMS and LHCb Collaborations. We find that the fit points to unequal wave functions of $\chi_{c1}$ and $\chi_{c2}$ states. |
2404.12437 | \'Angel Gil Muyor | Ricardo Z. Ferreira, \'Angel Gil Muyor | Lighten up Primordial Black Holes in the Galaxy with the QCD axion:
Signals at the LOFAR Telescope | 16 pages, 3 figures | null | null | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we study the luminosity that results from the conversion of QCD
axion particles into photons in the magnetic field of the plasma accreting onto
black holes (BHs). For the luminosities to be large two conditions need to be
met: i) there are large numbers of axions in the PBH surroundings as a result
of the so-called superradiant instability; ii) there exists a point inside the
accreting region where the plasma and axion masses are similar and there is
resonant axion-photon conversion. For BHs accreting from the interstellar
medium in our galaxy, the above conditions require the black hole to have
subsolar masses and we are therefore led to consider a population of primordial
black holes (PBHs). In the conservative window, where we stay within the
non-relativistic behavior of the plasma and neglect the possibility of
non-linear enhancement via magnetic stimulation, the typical frequencies of the
emitted photons lie on the low-radio band. We thus study the prospects for
detection using the LOFAR telescope, assuming the PBH abundance to be close to
the maximal allowed by observations. We find that for PBH and QCD axion with
masses in the range $10^{-5}-10^{-4}\, M_\odot$ and $4 \times 10^{-8}$ and $4
\times 10^{-7}$ eV, respectively, the flux density emitted by the closest PBH,
assuming it accretes from the warm ionized medium, can be detected at the LOFAR
telescope. Coincidently, the PBH mass range coincides with the range that would
explain the microlensing events found in OGLE. This might further motivate a
dedicated search of these signals in the LOFAR data and other radio telescopes.
| [
{
"created": "Thu, 18 Apr 2024 18:00:10 GMT",
"version": "v1"
}
] | 2024-04-22 | [
[
"Ferreira",
"Ricardo Z.",
""
],
[
"Muyor",
"Ángel Gil",
""
]
] | In this work, we study the luminosity that results from the conversion of QCD axion particles into photons in the magnetic field of the plasma accreting onto black holes (BHs). For the luminosities to be large two conditions need to be met: i) there are large numbers of axions in the PBH surroundings as a result of the so-called superradiant instability; ii) there exists a point inside the accreting region where the plasma and axion masses are similar and there is resonant axion-photon conversion. For BHs accreting from the interstellar medium in our galaxy, the above conditions require the black hole to have subsolar masses and we are therefore led to consider a population of primordial black holes (PBHs). In the conservative window, where we stay within the non-relativistic behavior of the plasma and neglect the possibility of non-linear enhancement via magnetic stimulation, the typical frequencies of the emitted photons lie on the low-radio band. We thus study the prospects for detection using the LOFAR telescope, assuming the PBH abundance to be close to the maximal allowed by observations. We find that for PBH and QCD axion with masses in the range $10^{-5}-10^{-4}\, M_\odot$ and $4 \times 10^{-8}$ and $4 \times 10^{-7}$ eV, respectively, the flux density emitted by the closest PBH, assuming it accretes from the warm ionized medium, can be detected at the LOFAR telescope. Coincidently, the PBH mass range coincides with the range that would explain the microlensing events found in OGLE. This might further motivate a dedicated search of these signals in the LOFAR data and other radio telescopes. |
1906.10849 | Daijiro Suematsu | Daijiro Suematsu | Pati-Salam unification with a spontaneous CP violation | 26 pages, 3 figures, some extension of the model to fix problems, a
version accepted for publication | Phys. Rev. D 100, 055019 (2019) | 10.1103/PhysRevD.100.055019 | KANAZAWA-19-03 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent neutrino oscillation experiments suggest that the PMNS matrix in the
lepton sector has a $CP$ violating phase as the CKM matrix in the quark sector.
However, origin of these phases in both matrices are not clarified by now.
Although complex Yukawa couplings could induce these phases, they remain as
free parameters of the model even in that case. If the $CP$ symmetry is
considered to be spontaneously broken, they are expected to be determined by
some physics at a much lower energy scale than the Planck scale. We study such
a possibility in a framework of Pati-Salam type unification. We also discuss
other phenomenological issues in it.
| [
{
"created": "Wed, 26 Jun 2019 05:12:59 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Aug 2019 00:06:26 GMT",
"version": "v2"
}
] | 2019-09-25 | [
[
"Suematsu",
"Daijiro",
""
]
] | Recent neutrino oscillation experiments suggest that the PMNS matrix in the lepton sector has a $CP$ violating phase as the CKM matrix in the quark sector. However, origin of these phases in both matrices are not clarified by now. Although complex Yukawa couplings could induce these phases, they remain as free parameters of the model even in that case. If the $CP$ symmetry is considered to be spontaneously broken, they are expected to be determined by some physics at a much lower energy scale than the Planck scale. We study such a possibility in a framework of Pati-Salam type unification. We also discuss other phenomenological issues in it. |
2110.10691 | Ennio Salvioni | Hsin-Chia Cheng, Lingfeng Li, Ennio Salvioni | A Theory of Dark Pions | 51 pages, 8 figures; v2: very minor modifications, matches published
version | JHEP 01 (2022) 122 | 10.1007/JHEP01(2022)122 | CERN-TH-2021-150 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a complete model of a dark QCD sector with light dark pions,
broadly motivated by hidden naturalness arguments. The dark quarks couple to
the Standard Model via irrelevant $Z$- and Higgs-portal operators, which encode
the low-energy effects of TeV-scale fermions interacting through Yukawa
couplings with the Higgs field. The dark pions, depending on their $CP$
properties, behave as either composite axion-like particles (ALPs) mixing with
the $Z$ or scalars mixing with the Higgs. The dark pion lifetimes fall
naturally in the most interesting region for present and proposed searches for
long-lived particles, at the LHC and beyond. This is demonstrated by studying
in detail three benchmark scenarios for the symmetries and structure of the
theory. Within a coherent framework, we analyze and compare the GeV-scale
signatures of flavor-changing meson decays to dark pions, the weak-scale decays
of $Z$ and Higgs bosons to hidden hadrons, and the TeV-scale signals of the
ultraviolet theory. New constraints are derived from $B$ decays at CMS and from
$Z$-initiated dark showers at LHCb, focusing on the displaced dimuon signature.
We also emphasize the strong potential sensitivity of ATLAS and CMS to dark
shower signals with large multiplicities and long lifetimes of the dark pions.
As a key part of our phenomenological study, we perform a new data-driven
calculation of the decays of a light ALP to exclusive hadronic Standard Model
final states. The results are provided in a general form, applicable to any
model with arbitrary flavor-diagonal couplings of the ALP to fermions.
| [
{
"created": "Wed, 20 Oct 2021 18:00:01 GMT",
"version": "v1"
},
{
"created": "Sun, 23 Jan 2022 14:25:39 GMT",
"version": "v2"
}
] | 2022-01-25 | [
[
"Cheng",
"Hsin-Chia",
""
],
[
"Li",
"Lingfeng",
""
],
[
"Salvioni",
"Ennio",
""
]
] | We present a complete model of a dark QCD sector with light dark pions, broadly motivated by hidden naturalness arguments. The dark quarks couple to the Standard Model via irrelevant $Z$- and Higgs-portal operators, which encode the low-energy effects of TeV-scale fermions interacting through Yukawa couplings with the Higgs field. The dark pions, depending on their $CP$ properties, behave as either composite axion-like particles (ALPs) mixing with the $Z$ or scalars mixing with the Higgs. The dark pion lifetimes fall naturally in the most interesting region for present and proposed searches for long-lived particles, at the LHC and beyond. This is demonstrated by studying in detail three benchmark scenarios for the symmetries and structure of the theory. Within a coherent framework, we analyze and compare the GeV-scale signatures of flavor-changing meson decays to dark pions, the weak-scale decays of $Z$ and Higgs bosons to hidden hadrons, and the TeV-scale signals of the ultraviolet theory. New constraints are derived from $B$ decays at CMS and from $Z$-initiated dark showers at LHCb, focusing on the displaced dimuon signature. We also emphasize the strong potential sensitivity of ATLAS and CMS to dark shower signals with large multiplicities and long lifetimes of the dark pions. As a key part of our phenomenological study, we perform a new data-driven calculation of the decays of a light ALP to exclusive hadronic Standard Model final states. The results are provided in a general form, applicable to any model with arbitrary flavor-diagonal couplings of the ALP to fermions. |
1407.1740 | Damian Ejlli | Damian Ejlli | Bounds on QCD axion mass and primordial magnetic field from CMB
$\mu$-distortion | Corrected inequality typos in the abstract. Minor changes | Phys. Rev. D 90, 123527 (2014) | 10.1103/PhysRevD.92.109902 | null | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The oscillation of the CMB photons into axions can cause CMB spectral
distortion in the presence of large scale magnetic field. With the COBE limit
on the $\mu$ parameter and a homogeneous magnetic field with strength
$B\lesssim 3.2$ nG at the horizon scale, an upper limit on the axion mass is
found to be, $m_a\lesssim 4.8\times 10^{-5}$ eV for the KSVZ axion model. On
the other hand, using the value of excluded axion mass $m_a\simeq 3.5\times
10^{-6}$ eV from the ADMX experiment together with the COBE bound on $\mu$, is
found $B\simeq 46$ nG for the KSVZ axion model and $B\simeq 130$ nG for DFSZ
axion model, for a homogeneous magnetic field with coherence length at the
present epoch $\lambda_B\simeq 1.3$ Mpc. Forecast on $B$ and $m_a$ for
PIXIE/PRISM expected sensitivity on $\mu$ are derived. If CMB $\mu$ distortion
would be detected by the future space missions PIXIE/PRISM and assuming that
the strength of the large scale magnetic field is close to its canonical value,
$B\simeq 1-3$ nG, axions in the mass range $2\, \mu$eV - $3\, \mu$eV would be
potential candidates of CMB $\mu$-distortion.
| [
{
"created": "Mon, 7 Jul 2014 15:26:20 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Jul 2014 15:50:08 GMT",
"version": "v2"
},
{
"created": "Wed, 19 Nov 2014 14:36:23 GMT",
"version": "v3"
},
{
"created": "Wed, 19 Aug 2015 11:29:36 GMT",
"version": "v4"
}
] | 2015-11-18 | [
[
"Ejlli",
"Damian",
""
]
] | The oscillation of the CMB photons into axions can cause CMB spectral distortion in the presence of large scale magnetic field. With the COBE limit on the $\mu$ parameter and a homogeneous magnetic field with strength $B\lesssim 3.2$ nG at the horizon scale, an upper limit on the axion mass is found to be, $m_a\lesssim 4.8\times 10^{-5}$ eV for the KSVZ axion model. On the other hand, using the value of excluded axion mass $m_a\simeq 3.5\times 10^{-6}$ eV from the ADMX experiment together with the COBE bound on $\mu$, is found $B\simeq 46$ nG for the KSVZ axion model and $B\simeq 130$ nG for DFSZ axion model, for a homogeneous magnetic field with coherence length at the present epoch $\lambda_B\simeq 1.3$ Mpc. Forecast on $B$ and $m_a$ for PIXIE/PRISM expected sensitivity on $\mu$ are derived. If CMB $\mu$ distortion would be detected by the future space missions PIXIE/PRISM and assuming that the strength of the large scale magnetic field is close to its canonical value, $B\simeq 1-3$ nG, axions in the mass range $2\, \mu$eV - $3\, \mu$eV would be potential candidates of CMB $\mu$-distortion. |
hep-ph/9807250 | Masaaki Kuroda | M. Kuroda and D. Schildknecht | A Simple Born-Form Approximation for e^+ e^- to W^+W^- at One Loop | 27 pages, 3 Postscript figures, uses epsf.sty | Nucl.Phys. B531 (1998) 24-48 | 10.1016/S0550-3213(98)00595-1 | CERN-TH/98-172, BI-TP 98/13 | hep-ph | null | A simple Born-form approximation at the one-loop level for e^+e^- to W^+ W^-
at high energies is given in analytic form. The different contributions to the
three invariant one-loop amplitudes, S_I^{(-)}(s,t) and S_Q^{(\pm)}(s,t),
determining the Born-form helicity amplitudes are thoroughly investigated
analytically and numerically. At energies above 500 GeV, the accuracy of the
simple Born-form approximation for the differential production cross section is
better than 1% for almost all W^+W^- production angles, independently of
whether the W^+W^- polarization is summed over, or whether a longitudinal or a
transverse polarization is selected for both the W^+ and the W^-.
| [
{
"created": "Mon, 6 Jul 1998 04:51:51 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Kuroda",
"M.",
""
],
[
"Schildknecht",
"D.",
""
]
] | A simple Born-form approximation at the one-loop level for e^+e^- to W^+ W^- at high energies is given in analytic form. The different contributions to the three invariant one-loop amplitudes, S_I^{(-)}(s,t) and S_Q^{(\pm)}(s,t), determining the Born-form helicity amplitudes are thoroughly investigated analytically and numerically. At energies above 500 GeV, the accuracy of the simple Born-form approximation for the differential production cross section is better than 1% for almost all W^+W^- production angles, independently of whether the W^+W^- polarization is summed over, or whether a longitudinal or a transverse polarization is selected for both the W^+ and the W^-. |
2001.05803 | Charanjit S. Aulakh | Charanjit S. Aulakh | Grand Pleromal Transmutation : condensates via Konsishi anomaly,
dimensional transmutation and ultraminimal GUTs | Published version. Section 2.2 (added in v2,v3 to educate reluctant
referee) has been removed as redundant because judged obviously known to any
competent reader by accepting referee ! Thus v4 is very close to v1 except
for correction of a significant typo in eqn(34) section 4.1 | Nuclear PhysicsB958(2020)115130 | 10.1016/j.nuclphysb.2020.115130 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using consistency requirements relating chiral condensates imposed by the so
called Generalized Konishi Anomaly, we show that dimensional transmutation via
gaugino condensation {\emph{in the ultraviolet}} drives gauge symmetry breaking
in a large class of {\emph{asymptotically strong}} Super Yang Mills Higgs
theories. For Adjoint multiplet type chiral superfields $\Phi$ (transforming as
$r \times \bar r$ representations of a non Abelian gauge group G), solution of
the Generalized Konishi Anomaly(GKA) equations allows calculation of quantum
corrected VEVs in terms of the dimensional transmutation scale $\Lambda_{UV}
\simeq M_X \, e^{\frac{8\pi^2}{ g^2(M_X) b_0}} $ which determines the gaugino
condensate. Thus the gauge coupling at the perturbative unification scale $M_X$
generates GUT symmetry breaking VEVs by non-perturbative dimensional
transmutation. This obviates the need for large(or any) input mass scales in
the superpotential. Rank reduction can be achieved by including pairs of chiral
superfields transforming as either $({\bf Q}(r),{ \bf\bar Q}(\bar r))$ or $
(\Sig((r\otimes r)_{symm})), \Sigb(({\bar r \otimes\bar r})_{symm})$, that form
trilinear matrix gauge invariants $\bar Q\cdot \Phi\cdot Q, \Sigb \cdot
\Phi\cdot \Sig $ with $\Phi$. Novel, robust and {\emph{ultraminimal}} Grand
unification algorithms emerge from the analysis. We sketch the structure of a
realistic Spin(10) model, with the $16$-plet of Spin(10) as the base
representation $r$, which mimics the realistic Minimal Supersymmetric GUT but
contains even fewer free parameters. We argue that our results point to a large
extension of the dominant and normative paradigms of Asymptotic Freedom$/$IR
colour confinement and potential driven spontaneous symmetry breaking that have
long ruled gauge theories.
| [
{
"created": "Thu, 16 Jan 2020 14:04:58 GMT",
"version": "v1"
},
{
"created": "Sat, 21 Mar 2020 13:53:24 GMT",
"version": "v2"
},
{
"created": "Mon, 20 Apr 2020 13:45:02 GMT",
"version": "v3"
},
{
"created": "Sun, 16 Aug 2020 12:10:22 GMT",
"version": "v4"
}
] | 2020-08-18 | [
[
"Aulakh",
"Charanjit S.",
""
]
] | Using consistency requirements relating chiral condensates imposed by the so called Generalized Konishi Anomaly, we show that dimensional transmutation via gaugino condensation {\emph{in the ultraviolet}} drives gauge symmetry breaking in a large class of {\emph{asymptotically strong}} Super Yang Mills Higgs theories. For Adjoint multiplet type chiral superfields $\Phi$ (transforming as $r \times \bar r$ representations of a non Abelian gauge group G), solution of the Generalized Konishi Anomaly(GKA) equations allows calculation of quantum corrected VEVs in terms of the dimensional transmutation scale $\Lambda_{UV} \simeq M_X \, e^{\frac{8\pi^2}{ g^2(M_X) b_0}} $ which determines the gaugino condensate. Thus the gauge coupling at the perturbative unification scale $M_X$ generates GUT symmetry breaking VEVs by non-perturbative dimensional transmutation. This obviates the need for large(or any) input mass scales in the superpotential. Rank reduction can be achieved by including pairs of chiral superfields transforming as either $({\bf Q}(r),{ \bf\bar Q}(\bar r))$ or $ (\Sig((r\otimes r)_{symm})), \Sigb(({\bar r \otimes\bar r})_{symm})$, that form trilinear matrix gauge invariants $\bar Q\cdot \Phi\cdot Q, \Sigb \cdot \Phi\cdot \Sig $ with $\Phi$. Novel, robust and {\emph{ultraminimal}} Grand unification algorithms emerge from the analysis. We sketch the structure of a realistic Spin(10) model, with the $16$-plet of Spin(10) as the base representation $r$, which mimics the realistic Minimal Supersymmetric GUT but contains even fewer free parameters. We argue that our results point to a large extension of the dominant and normative paradigms of Asymptotic Freedom$/$IR colour confinement and potential driven spontaneous symmetry breaking that have long ruled gauge theories. |
hep-ph/0605177 | Enrico Lunghi | Enrico Lunghi, Werner Porod, Oscar Vives | Analysis of enhanced tan(beta) corrections in MFV GUT scenarios | 47 pages, 16 figures (best viewed printed or in pdf format), updated
lattice inputs used, version submitted to PRD | Phys.Rev.D74:075003,2006 | 10.1103/PhysRevD.74.075003 | null | hep-ph hep-ex | null | We analyse a minimal supersymmetric standard model (MSSM) taking a minimal
flavour violation (MFV) structure at the GUT scale. We evaluate the parameters
at the electroweak scale taking into account the full flavour structure in the
evolution of the renormalization group equations. We concentrate mainly on the
decay Bs -> mu mu and its correlations with other observables like b -> s
gamma, b -> s l l, Delta M_Bs and the anomalous magnetic moment of the muon. We
restrict our analysis to the regions in parameter space consistent with the
dark matter constraints. We find that the BR(Bs -> mu mu) can exceed the
current experimental limit in the regions of parameter space which are allowed
by all other constraints thus providing an additional bound on supersymmetric
parameters. This holds even in the constrained MSSM. Assuming an hypothetical
measurement of BR(Bs -> mu mu) ~ 10^-7 we analyse the predicted MSSM spectrum
and flavour violating decay modes of supersymmetric particles which are found
to be small.
| [
{
"created": "Mon, 15 May 2006 19:24:22 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Jul 2006 21:47:44 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Lunghi",
"Enrico",
""
],
[
"Porod",
"Werner",
""
],
[
"Vives",
"Oscar",
""
]
] | We analyse a minimal supersymmetric standard model (MSSM) taking a minimal flavour violation (MFV) structure at the GUT scale. We evaluate the parameters at the electroweak scale taking into account the full flavour structure in the evolution of the renormalization group equations. We concentrate mainly on the decay Bs -> mu mu and its correlations with other observables like b -> s gamma, b -> s l l, Delta M_Bs and the anomalous magnetic moment of the muon. We restrict our analysis to the regions in parameter space consistent with the dark matter constraints. We find that the BR(Bs -> mu mu) can exceed the current experimental limit in the regions of parameter space which are allowed by all other constraints thus providing an additional bound on supersymmetric parameters. This holds even in the constrained MSSM. Assuming an hypothetical measurement of BR(Bs -> mu mu) ~ 10^-7 we analyse the predicted MSSM spectrum and flavour violating decay modes of supersymmetric particles which are found to be small. |
1408.1905 | Tomoya Hayata | Tomoya Hayata, Arata Yamamoto | Inhomogeneous Polyakov loop induced by inhomogeneous chiral condensates | 5 pages, 3 figures | null | 10.1016/j.physletb.2015.04.025 | RIKEN-QHP-160 | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the spatial inhomogeneity of the Polyakov loop induced by
inhomogeneous chiral condensates. We formulate an effective model of gluons on
the background fields of chiral condensates, and perform its lattice
simulation. On the background of inhomogeneous chiral condensates, the Polyakov
loop exhibits an in-phase spatial oscillation with the chiral condensates. We
also analyze the heavy quark potential and show that the inhomogeneous Polyakov
loop indicates the inhomogeneous confinement of heavy quarks.
| [
{
"created": "Fri, 8 Aug 2014 16:34:20 GMT",
"version": "v1"
}
] | 2015-05-20 | [
[
"Hayata",
"Tomoya",
""
],
[
"Yamamoto",
"Arata",
""
]
] | We study the spatial inhomogeneity of the Polyakov loop induced by inhomogeneous chiral condensates. We formulate an effective model of gluons on the background fields of chiral condensates, and perform its lattice simulation. On the background of inhomogeneous chiral condensates, the Polyakov loop exhibits an in-phase spatial oscillation with the chiral condensates. We also analyze the heavy quark potential and show that the inhomogeneous Polyakov loop indicates the inhomogeneous confinement of heavy quarks. |
2212.02333 | Van Que Tran | Van Que Tran and Tzu-Chiang Yuan | Charged Lepton Flavor Violating Radiative Decays $l_i \to l_j \gamma$ in
G2HDM | 38 pages, 7 figures; added Appendices C and D for more information;
matches version accepted for publication in JHEP | null | 10.1007/JHEP02(2023)117 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We compute the electromagnetic form factors of the $l_i l_j \gamma$ vertex at
one-loop level in the minimal G2HDM which has a sub-GeV vector dark matter
candidate. The results are applied to the radiative decay rates for the charged
lepton flavor violating processes $l_i \to l_j \gamma$, and the anomalous
magnetic dipole moment and the electric dipole moment of the charged lepton. To
numerically compute the branching ratio for $\mu \to e \gamma$ and compare with
the latest experimental limit from MEG, we adapt our previous parameter space
scan that is consistent with the relic density and constraints from direct
searches of dark matter, $W$ and $Z$ mass measurements, as well as the LHC
Higgs signal strengths and invisible width. While the extra contributions are
at least an order of magnitude smaller than required to explain the $\sim 4.2
\sigma$ discrepancy in the muon anomaly, the existing MEG limit imposes
stringent constraint on the parameter space. The remaining viable parameter
space can be further probed by the MEG II sensitivity for $\mu \to e \gamma$ as
well as from the direct searches of sub-GeV dark matter in foreseeable future.
Higher loop contributions may be significant to resolve the discrepancy in the
muon anomaly and generate a non-vanishing electric dipole moments for the
standard model quarks and leptons in G2HDM.
| [
{
"created": "Mon, 5 Dec 2022 15:08:06 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Jan 2023 08:41:09 GMT",
"version": "v2"
}
] | 2023-03-22 | [
[
"Tran",
"Van Que",
""
],
[
"Yuan",
"Tzu-Chiang",
""
]
] | We compute the electromagnetic form factors of the $l_i l_j \gamma$ vertex at one-loop level in the minimal G2HDM which has a sub-GeV vector dark matter candidate. The results are applied to the radiative decay rates for the charged lepton flavor violating processes $l_i \to l_j \gamma$, and the anomalous magnetic dipole moment and the electric dipole moment of the charged lepton. To numerically compute the branching ratio for $\mu \to e \gamma$ and compare with the latest experimental limit from MEG, we adapt our previous parameter space scan that is consistent with the relic density and constraints from direct searches of dark matter, $W$ and $Z$ mass measurements, as well as the LHC Higgs signal strengths and invisible width. While the extra contributions are at least an order of magnitude smaller than required to explain the $\sim 4.2 \sigma$ discrepancy in the muon anomaly, the existing MEG limit imposes stringent constraint on the parameter space. The remaining viable parameter space can be further probed by the MEG II sensitivity for $\mu \to e \gamma$ as well as from the direct searches of sub-GeV dark matter in foreseeable future. Higher loop contributions may be significant to resolve the discrepancy in the muon anomaly and generate a non-vanishing electric dipole moments for the standard model quarks and leptons in G2HDM. |
hep-ph/9810274 | Alan Kostelecky | Alan Kostelecky | CPT and Lorentz Tests in the Standard Model | 8 pages, to appear in the proceedings of PASCOS 98, Northeastern
University, Boston, March 1998 | null | null | IUHET 387, April 1998 | hep-ph | null | A general Lorentz-violating extension of the minimal SU(3) x SU(2) x U(1)
standard model is described, including both CPT-even and CPT-odd terms. Some
theoretical properties and experimental implications are given. The extension
can be regarded as a low-energy limit of a physically relevant
Lorentz-covariant fundamental theory in which spontaneous Lorentz violation
occurs.
| [
{
"created": "Wed, 7 Oct 1998 14:51:57 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kostelecky",
"Alan",
""
]
] | A general Lorentz-violating extension of the minimal SU(3) x SU(2) x U(1) standard model is described, including both CPT-even and CPT-odd terms. Some theoretical properties and experimental implications are given. The extension can be regarded as a low-energy limit of a physically relevant Lorentz-covariant fundamental theory in which spontaneous Lorentz violation occurs. |
2012.07202 | Dimitrios Karamitros | Paola Arias, Dimitrios Karamitros, Leszek Roszkowski | Frozen-in fermionic singlet dark matter in non-standard cosmology with a
decaying fluid | 40 pages, 17 figures; v2: References updated, typos corrected,
matches version published in JCAP | null | 10.1088/1475-7516/2021/05/041 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a detailed study of dark matter production via freeze-in under the
assumption that some fluid dominates the early Universe before depositing its
energy to the plasma causing entropy injection. As a dark matter candidate we
consider a fermionic singlet that is produced through its interactions with a
scalar particle in the thermal plasma. The fluid alters the expansion rate of
the Universe, as well as the scaling of the temperature, which significantly
affects the evolution of both the number density and the mean momentum of the
dark matter particle. We identify and discuss in detail the effects of the
evolution of these quantities by considering several examples representing dark
matter production at different stages of expansion and entropy injection. We
find that, since the dark matter density is reduced when the entropy injection
to the plasma continues after freeze-in, in order to reproduce its
observational value an enhanced rate of dark matter production is required
relative to standard cosmology. Furthermore, the impact of the assumed
non-standard cosmological history on the dark matter mean momentum can result
in either a relaxed or a tightened bound on the dark matter mass from large
structure formation data.
| [
{
"created": "Mon, 14 Dec 2020 01:31:26 GMT",
"version": "v1"
},
{
"created": "Mon, 24 May 2021 10:52:45 GMT",
"version": "v2"
}
] | 2021-05-26 | [
[
"Arias",
"Paola",
""
],
[
"Karamitros",
"Dimitrios",
""
],
[
"Roszkowski",
"Leszek",
""
]
] | We perform a detailed study of dark matter production via freeze-in under the assumption that some fluid dominates the early Universe before depositing its energy to the plasma causing entropy injection. As a dark matter candidate we consider a fermionic singlet that is produced through its interactions with a scalar particle in the thermal plasma. The fluid alters the expansion rate of the Universe, as well as the scaling of the temperature, which significantly affects the evolution of both the number density and the mean momentum of the dark matter particle. We identify and discuss in detail the effects of the evolution of these quantities by considering several examples representing dark matter production at different stages of expansion and entropy injection. We find that, since the dark matter density is reduced when the entropy injection to the plasma continues after freeze-in, in order to reproduce its observational value an enhanced rate of dark matter production is required relative to standard cosmology. Furthermore, the impact of the assumed non-standard cosmological history on the dark matter mean momentum can result in either a relaxed or a tightened bound on the dark matter mass from large structure formation data. |
hep-ph/0408130 | Ralf Hofmann | Ralf Hofmann | Analytical approach to SU(2) Yang-Mills thermodynamics | 5 pages, no figure, contribution to proceedings of SEWM 2004 | null | 10.1142/9789812702159_0056 | null | hep-ph | null | We propose an analytical approach to SU(2) Yang-Mills thermodynamics. The
existence of a macroscopic and rigid adjoint Higgs field, generated by dilute
trivial-holonomy calorons at large temperature $T$ (electric phase), implies a
twofold degeneracy of the ground state which signals a broken electric $Z_2$
symmetry. A finite energy density $\propto T$ of the ground state arises due to
caloron interaction. An evolution equation for the effective gauge coupling,
derived from thermodynamical self-consistency, predicts a second-order like
transition (seen in lattice simulations) at $T_c$ to a phase where monopoles
are condensed and off-Cartan excitations decoupled. In this magnetic phase the
ground state is unique and dominates the pressure (negative total pressure).
While the magnetic phase has a massive, propagating 'photon' it confines
fundamental matter (pre-confinement). The temperature dependence of the
magnetic gauge coupling predicts the transition to the confining phase at
$T_C\sim \frac{T_c}{1.9}$ where center-vortex loops condense and the 'photon'
decouples. We believe that this transition is 'swallowed' by finite-size
artefacts in lattice simulations. No thermodynamical connection exists between
the confining and the magnetic phase.
| [
{
"created": "Tue, 10 Aug 2004 14:26:26 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Hofmann",
"Ralf",
""
]
] | We propose an analytical approach to SU(2) Yang-Mills thermodynamics. The existence of a macroscopic and rigid adjoint Higgs field, generated by dilute trivial-holonomy calorons at large temperature $T$ (electric phase), implies a twofold degeneracy of the ground state which signals a broken electric $Z_2$ symmetry. A finite energy density $\propto T$ of the ground state arises due to caloron interaction. An evolution equation for the effective gauge coupling, derived from thermodynamical self-consistency, predicts a second-order like transition (seen in lattice simulations) at $T_c$ to a phase where monopoles are condensed and off-Cartan excitations decoupled. In this magnetic phase the ground state is unique and dominates the pressure (negative total pressure). While the magnetic phase has a massive, propagating 'photon' it confines fundamental matter (pre-confinement). The temperature dependence of the magnetic gauge coupling predicts the transition to the confining phase at $T_C\sim \frac{T_c}{1.9}$ where center-vortex loops condense and the 'photon' decouples. We believe that this transition is 'swallowed' by finite-size artefacts in lattice simulations. No thermodynamical connection exists between the confining and the magnetic phase. |
1209.2822 | Kensuke Homma | T. Tajima and K. Homma | Fundamental Physics Explored with High Intensity Laser | 46 pages, 5 figures | International Journal of Modern Physics A Vol. 27, No. 25 (2012)
1230027 | 10.1142/S0217751X1230027X | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Over the last Century the method of particle acceleration to high energies
has become the prime approach to explore the fundamental nature of matter in
laboratory. It appears that the latest search of the contemporary accelerator
based on the colliders shows a sign of saturation (or at least a slow-down) in
increasing its energy and other necessary parameters to extend this frontier.
We suggest two pronged approach enabled by the recent progress in high
intensity lasers.
| [
{
"created": "Thu, 13 Sep 2012 09:06:53 GMT",
"version": "v1"
}
] | 2012-11-12 | [
[
"Tajima",
"T.",
""
],
[
"Homma",
"K.",
""
]
] | Over the last Century the method of particle acceleration to high energies has become the prime approach to explore the fundamental nature of matter in laboratory. It appears that the latest search of the contemporary accelerator based on the colliders shows a sign of saturation (or at least a slow-down) in increasing its energy and other necessary parameters to extend this frontier. We suggest two pronged approach enabled by the recent progress in high intensity lasers. |
2104.09688 | Oleksii Mikulenko | Alexey Boyarsky, Oleksii Mikulenko, Maksym Ovchynnikov, Lesya
Shchutska | Searches for new physics at SND@LHC | 28 pages, 9 figures | null | 10.1007/JHEP03(2022)006 | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | SND@LHC is an approved experiment equipped to detect scattering of neutrinos
produced in the far-forward direction at the LHC, and aimed to measure their
properties. In addition, the detector has a potential to search for new feebly
interacting particles (FIPs) that may be produced in proton-proton collisions.
In this paper, we discuss FIPs signatures at SND@LHC considering two classes of
particles: stable FIPs that may be detected via their scattering, and unstable
FIPs that decay inside the detector. We estimate the sensitivity of SND@LHC to
probe scattering of leptophobic dark matter, and to detect decays of neutrino,
scalar, and vector portal particles. Finally, we also compare and qualitatively
analyze the potential of SND@LHC and FASER/FASER{\nu} experiments for these
searches.
| [
{
"created": "Mon, 19 Apr 2021 23:37:40 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Feb 2022 22:18:31 GMT",
"version": "v2"
}
] | 2022-03-04 | [
[
"Boyarsky",
"Alexey",
""
],
[
"Mikulenko",
"Oleksii",
""
],
[
"Ovchynnikov",
"Maksym",
""
],
[
"Shchutska",
"Lesya",
""
]
] | SND@LHC is an approved experiment equipped to detect scattering of neutrinos produced in the far-forward direction at the LHC, and aimed to measure their properties. In addition, the detector has a potential to search for new feebly interacting particles (FIPs) that may be produced in proton-proton collisions. In this paper, we discuss FIPs signatures at SND@LHC considering two classes of particles: stable FIPs that may be detected via their scattering, and unstable FIPs that decay inside the detector. We estimate the sensitivity of SND@LHC to probe scattering of leptophobic dark matter, and to detect decays of neutrino, scalar, and vector portal particles. Finally, we also compare and qualitatively analyze the potential of SND@LHC and FASER/FASER{\nu} experiments for these searches. |
hep-ph/0012075 | Aaron Pierce | H. Murayama, A. Pierce (UC-Berkeley, LBNL) | Energy Spectra of Reactor Neutrinos at KamLAND | 7 pages, 7 figures. References added. Minor changes in wording | Phys.Rev.D65:013012,2002 | 10.1103/PhysRevD.65.013012 | UCB-PTH-00/40, LBNL-47179 | hep-ph | null | The upcoming reactor neutrino experiment, KamLAND, has the ability to explore
the Large Mixing Angle (LMA) solution to the solar neutrino problem. Here, we
investigate the precision to which KamLAND should be able to measure these
parameters, utilizing the distortion of the energy spectrum of reactor
neutrinos. Incomplete knowledge of the fuel composition of the reactors will
lead to some error on this measurement. We estimate the size of this effect.
| [
{
"created": "Wed, 6 Dec 2000 21:10:38 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Dec 2000 01:39:40 GMT",
"version": "v2"
},
{
"created": "Sat, 9 Dec 2000 22:19:00 GMT",
"version": "v3"
}
] | 2009-09-29 | [
[
"Murayama",
"H.",
"",
"UC-Berkeley, LBNL"
],
[
"Pierce",
"A.",
"",
"UC-Berkeley, LBNL"
]
] | The upcoming reactor neutrino experiment, KamLAND, has the ability to explore the Large Mixing Angle (LMA) solution to the solar neutrino problem. Here, we investigate the precision to which KamLAND should be able to measure these parameters, utilizing the distortion of the energy spectrum of reactor neutrinos. Incomplete knowledge of the fuel composition of the reactors will lead to some error on this measurement. We estimate the size of this effect. |
hep-ph/0411378 | Ramona Vogt | R. Vogt | Shadowing and Absorption Effects on J/psi Production in dA Collisions | 22 pages, 11 figures, uses revtex | Phys.Rev.C71:054902,2005 | 10.1103/PhysRevC.71.054902 | LBNL-56656 | hep-ph | null | We study medium modifications of J/psi production in cold nuclear media in
deuterium-nucleus collisions. We discuss several parameterizations of the
modifications of the parton densities in the nucleus, known as shadowing, an
initial-state effect. We also include absorption of the produced J/psi by
nucleons, a final-state effect. Both spatially homogeneous and inhomogeneous
shadowing and absorption are considered. We use the number of binary
nucleon-nucleon collisions as a centrality measure. Results are presented for
d+Au collisions at sqrt{S_{NN}} = 200 GeV and for d+Pb collisions at
sqrt{S_{NN}} = 6.2 TeV. To contrast the centrality dependence in pA and dA
collisions, we also present pPb results at sqrt{S_{NN}} = 8.8 TeV.
| [
{
"created": "Mon, 29 Nov 2004 20:53:21 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Vogt",
"R.",
""
]
] | We study medium modifications of J/psi production in cold nuclear media in deuterium-nucleus collisions. We discuss several parameterizations of the modifications of the parton densities in the nucleus, known as shadowing, an initial-state effect. We also include absorption of the produced J/psi by nucleons, a final-state effect. Both spatially homogeneous and inhomogeneous shadowing and absorption are considered. We use the number of binary nucleon-nucleon collisions as a centrality measure. Results are presented for d+Au collisions at sqrt{S_{NN}} = 200 GeV and for d+Pb collisions at sqrt{S_{NN}} = 6.2 TeV. To contrast the centrality dependence in pA and dA collisions, we also present pPb results at sqrt{S_{NN}} = 8.8 TeV. |
hep-ph/0410320 | Yuri Goncharov | Yu. P. Goncharov (Sankt-Petersburg State Polytechnical University,
Russia) A. A. Bytsenko (Londrina University, Brazil) | Estimates of the gluon concentrations in the confining SU(3)-Yang-Mills
field for the first three states of charmonium | 15 pages, LaTeX | Phys.Lett. B602 (2004) 86-96 | 10.1016/j.physletb.2004.09.047 | null | hep-ph | null | The estimates of the gluon concentrations in the classical SU(3)-Yang-Mills
field modelling confinement are given for the first three states of charmonium
whose spectrum is tuned by calculating electromagnetic transitions among the
mentioned levels in dipole approximation. For comparison the corresponding
estimates for the photon concentration in the ground state of positronium
(parapositronium and orthopositronium) are also adduced.
| [
{
"created": "Sun, 24 Oct 2004 15:15:37 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Goncharov",
"Yu. P.",
"",
"Sankt-Petersburg State Polytechnical University,\n Russia"
],
[
"Bytsenko",
"A. A.",
"",
"Londrina University, Brazil"
]
] | The estimates of the gluon concentrations in the classical SU(3)-Yang-Mills field modelling confinement are given for the first three states of charmonium whose spectrum is tuned by calculating electromagnetic transitions among the mentioned levels in dipole approximation. For comparison the corresponding estimates for the photon concentration in the ground state of positronium (parapositronium and orthopositronium) are also adduced. |
1503.02636 | Ben Gripaios | Ben Gripaios | Lectures on Physics Beyond the Standard Model | 31 pp | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | These four lectures, given at the British Universities Summer School in
Theoretical Elementary Particle Physics (BUSSTEPP), held in 2014 in
Southampton, are a brief introduction to a selection of current topics in
physics Beyond the Standard Model.
| [
{
"created": "Mon, 9 Mar 2015 19:35:01 GMT",
"version": "v1"
}
] | 2015-03-10 | [
[
"Gripaios",
"Ben",
""
]
] | These four lectures, given at the British Universities Summer School in Theoretical Elementary Particle Physics (BUSSTEPP), held in 2014 in Southampton, are a brief introduction to a selection of current topics in physics Beyond the Standard Model. |
hep-ph/9811344 | Ana M. Mourao | Ana M. Mourao and Anna Rossi (IST - Lisbon) | Neutrino Magnetic Moment and Solar Neutrino Experiments | latex file, 4 pages, including 3 postscript figures. Talk given by A.
Mourao at the Neutrino 98 Conference (Japan). To appear in the Proceedings | Nucl.Phys.Proc.Suppl. 77 (1999) 89-92 | 10.1016/S0920-5632(99)00402-8 | DF/IST-5.98,FISIST/13-98/CFIF/CENTRA | hep-ph | null | We have studied the effect of a non-vanishing neutrino magnetic moment \
($\mu_{\nu}$) on the $\nu_{\rm x}$ ({x=$e,\mu,\tau$}) elastic scattering off
electrons for the Super-Kamiokande detector. The bounds on the $\mu_{\nu}$ we
have obtained are comparable to that extracted from laboratory experiments.
Furthemore, we outline the potential of the Borexino experiment which may be
sensitive to neutrino magnetic moments $\lsim 10^{-10}\mu_B$. In our analysis
we have considered both cases of Majorana and Dirac neutrinos.
| [
{
"created": "Mon, 16 Nov 1998 14:00:48 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Mourao",
"Ana M.",
"",
"IST - Lisbon"
],
[
"Rossi",
"Anna",
"",
"IST - Lisbon"
]
] | We have studied the effect of a non-vanishing neutrino magnetic moment \ ($\mu_{\nu}$) on the $\nu_{\rm x}$ ({x=$e,\mu,\tau$}) elastic scattering off electrons for the Super-Kamiokande detector. The bounds on the $\mu_{\nu}$ we have obtained are comparable to that extracted from laboratory experiments. Furthemore, we outline the potential of the Borexino experiment which may be sensitive to neutrino magnetic moments $\lsim 10^{-10}\mu_B$. In our analysis we have considered both cases of Majorana and Dirac neutrinos. |
1809.09452 | Alexander Lenz | Alexander Lenz | Theory of Mixing and CP violation | 11 pages, 3 figures, comments to my rating system welcome; prepared
for the Proceedings of the Sixth Annual Conference on Large Hadron Collider
Physics (LHCP2018), 4-9 June 2018, Bologna, Italy | null | null | IPPP/18/84 | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review the current status of B-mixing observables and point out the
crucial importance of a control of the hadronic uncertainties for ruling out or
confirming hints of BSM physics. In addition we introduce a rating system for
theory predictions for lifetimes and mixing observables, that classifies the
quality of the corresponding SM values ranging from no star to ****
| [
{
"created": "Tue, 25 Sep 2018 13:06:56 GMT",
"version": "v1"
}
] | 2018-09-26 | [
[
"Lenz",
"Alexander",
""
]
] | We review the current status of B-mixing observables and point out the crucial importance of a control of the hadronic uncertainties for ruling out or confirming hints of BSM physics. In addition we introduce a rating system for theory predictions for lifetimes and mixing observables, that classifies the quality of the corresponding SM values ranging from no star to **** |
hep-ph/0004063 | Ivanov. D. Yu | A.P.Burichenko | The "recoil" correction of order $m \alpha^6$ to hyperfine splitting of
positronium ground state | 28 pages, latex including latex figures | null | 10.1134/1.1409504 | null | hep-ph | null | The "recoil" correction of order $m \alpha^6$ to the hyperfine splitting of
positronium ground state was found. The formalism employed is based on the
noncovariant perturbation theory in QED. Equation for two-particle component of
full (many-body) wave function is used, in which effective Hamiltonian depends
on the energy of a system. The effective Hamiltonian is not restricted to the
nonrelativistic region, so there is no need in any regularization. To evaluate
integrals over loop momenta, they are divided into "hard" and "soft" parts,
coming from large and small momenta respectively. Soft contributions were found
analytically, and hard ones are evaluated by numerical integration. Some soft
terms due to the retardation cancel each other. To calculate the "hard"
contributions, a great number of noncovariant graphs is replaced by only a few
covariant ones. The hard contribution was found in two ways. The first way is
to evaluate contributions of separate graphs, using the Coulomb gauge. The
second one is to calculate full hard contribution as a whole using the Feynman
gauge. The final result for the "recoil" correction is $0.381(6) m\al^6$ and
agrees with those of previous papers. Diagram-to-diagram comparison with the
revised results of Adkins&Sapirstein was done. All the results agree, so the
"recoil" correction is now firmly established. This means a considerable
disagreement with the experimental data.
| [
{
"created": "Fri, 7 Apr 2000 06:20:31 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Burichenko",
"A. P.",
""
]
] | The "recoil" correction of order $m \alpha^6$ to the hyperfine splitting of positronium ground state was found. The formalism employed is based on the noncovariant perturbation theory in QED. Equation for two-particle component of full (many-body) wave function is used, in which effective Hamiltonian depends on the energy of a system. The effective Hamiltonian is not restricted to the nonrelativistic region, so there is no need in any regularization. To evaluate integrals over loop momenta, they are divided into "hard" and "soft" parts, coming from large and small momenta respectively. Soft contributions were found analytically, and hard ones are evaluated by numerical integration. Some soft terms due to the retardation cancel each other. To calculate the "hard" contributions, a great number of noncovariant graphs is replaced by only a few covariant ones. The hard contribution was found in two ways. The first way is to evaluate contributions of separate graphs, using the Coulomb gauge. The second one is to calculate full hard contribution as a whole using the Feynman gauge. The final result for the "recoil" correction is $0.381(6) m\al^6$ and agrees with those of previous papers. Diagram-to-diagram comparison with the revised results of Adkins&Sapirstein was done. All the results agree, so the "recoil" correction is now firmly established. This means a considerable disagreement with the experimental data. |
1807.05250 | Alexandre Deur | A. Deur, S. J. Brodsky, G. F. de Teramond | The Spin Structure of the Nucleon | 119 pages, 19 figures. Final version published in Report on Progress
in Physics | null | 10.1088/1361-6633/ab0b8f | JLAB-PHY-18-2760, SLAC-PUB-17279 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review the present understanding of the spin structure of protons and
neutrons, the fundamental building blocks of nuclei collectively known as
nucleons. The field of nucleon spin provides a critical window for testing
Quantum Chromodynamics (QCD), the gauge theory of the strong interactions since
it involves fundamental aspects of hadron structure, and it can be probed in
detail in experiments, particularly deep inelastic lepton scattering on
polarized targets. QCD was initially probed in high energy deep inelastic
lepton scattering with unpolarized beams and targets. With time, interest
shifted from testing perturbative QCD to illuminating the nucleon structure
itself. In fact, the spin degrees of freedom of hadrons provide an essential
and detailed verification of both perturbative and nonperturbative QCD
dynamics. Nucleon spin was initially thought of coming mostly from the spin of
its quark constituents, based on intuition from the parton model. However, the
first experiments showed that this expectation was incorrect. It is now clear
that nucleon physics is much more complex, involving quark orbital angular
momenta as well as gluonic and sea quark contributions. Thus, the nucleon spin
structure remains a most active aspect of QCD research, involving important
advances such as the developments of generalized parton distributions (GPD) and
transverse momentum distributions (TMD). Elastic and inelastic lepton-proton
scattering, as well as photoabsorption experiments provide various ways to
investigate non-perturbative QCD. Fundamental sum rules -- such as the Bjorken
sum rule for polarized photoabsorption on polarized nucleons -- are also in the
non-perturbative domain. This realization triggered a vigorous program to link
the low energy effective hadronic description of the strong interactions to
fundamental quarks and gluon degrees of freedom of...
| [
{
"created": "Fri, 13 Jul 2018 19:12:15 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Dec 2018 01:45:45 GMT",
"version": "v2"
},
{
"created": "Wed, 24 Apr 2019 20:18:40 GMT",
"version": "v3"
}
] | 2019-04-26 | [
[
"Deur",
"A.",
""
],
[
"Brodsky",
"S. J.",
""
],
[
"de Teramond",
"G. F.",
""
]
] | We review the present understanding of the spin structure of protons and neutrons, the fundamental building blocks of nuclei collectively known as nucleons. The field of nucleon spin provides a critical window for testing Quantum Chromodynamics (QCD), the gauge theory of the strong interactions since it involves fundamental aspects of hadron structure, and it can be probed in detail in experiments, particularly deep inelastic lepton scattering on polarized targets. QCD was initially probed in high energy deep inelastic lepton scattering with unpolarized beams and targets. With time, interest shifted from testing perturbative QCD to illuminating the nucleon structure itself. In fact, the spin degrees of freedom of hadrons provide an essential and detailed verification of both perturbative and nonperturbative QCD dynamics. Nucleon spin was initially thought of coming mostly from the spin of its quark constituents, based on intuition from the parton model. However, the first experiments showed that this expectation was incorrect. It is now clear that nucleon physics is much more complex, involving quark orbital angular momenta as well as gluonic and sea quark contributions. Thus, the nucleon spin structure remains a most active aspect of QCD research, involving important advances such as the developments of generalized parton distributions (GPD) and transverse momentum distributions (TMD). Elastic and inelastic lepton-proton scattering, as well as photoabsorption experiments provide various ways to investigate non-perturbative QCD. Fundamental sum rules -- such as the Bjorken sum rule for polarized photoabsorption on polarized nucleons -- are also in the non-perturbative domain. This realization triggered a vigorous program to link the low energy effective hadronic description of the strong interactions to fundamental quarks and gluon degrees of freedom of... |
1312.2961 | Thomas Metcalf | Mar Bastero-Gil, Arjun Berera, Thomas P. Metcalf, Joao G. Rosa | Delaying the waterfall transition in warm hybrid inflation | 28 pages, 5 figures | null | 10.1088/1475-7516/2014/03/023 | Edinburgh 2013/34 | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the dynamics and observational predictions of supersymmetric
hybrid inflation in the warm regime, where dissipative effects are mediated by
the waterfall fields and their subsequent decay into light degrees of freedom.
This produces a quasi-thermal radiation bath with a slowly-varying temperature
during inflation and further damps the inflaton's motion, thus prolonging
inflation. As in the standard supercooled scenario, inflation ends when the
waterfall fields become tachyonic and can no longer sustain a nearly constant
vacuum energy, but the interaction with the radiation bath makes the waterfall
fields effectively heavier and delays the phase transition to the
supersymmetric minimum. In this work, we analyze for the first time the effects
of finite temperature corrections and SUSY mass splittings on the quantum
effective potential and the resulting dissipation coefficient. We show, in
particular, that dissipation can significantly delay the onset of the tachyonic
instability to yield 50-60 e-folds of inflation and an observationally
consistent primordial spectrum, which is not possible in the standard
supercooled regime when inflation is driven by radiative corrections.
| [
{
"created": "Tue, 10 Dec 2013 21:00:15 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Bastero-Gil",
"Mar",
""
],
[
"Berera",
"Arjun",
""
],
[
"Metcalf",
"Thomas P.",
""
],
[
"Rosa",
"Joao G.",
""
]
] | We analyze the dynamics and observational predictions of supersymmetric hybrid inflation in the warm regime, where dissipative effects are mediated by the waterfall fields and their subsequent decay into light degrees of freedom. This produces a quasi-thermal radiation bath with a slowly-varying temperature during inflation and further damps the inflaton's motion, thus prolonging inflation. As in the standard supercooled scenario, inflation ends when the waterfall fields become tachyonic and can no longer sustain a nearly constant vacuum energy, but the interaction with the radiation bath makes the waterfall fields effectively heavier and delays the phase transition to the supersymmetric minimum. In this work, we analyze for the first time the effects of finite temperature corrections and SUSY mass splittings on the quantum effective potential and the resulting dissipation coefficient. We show, in particular, that dissipation can significantly delay the onset of the tachyonic instability to yield 50-60 e-folds of inflation and an observationally consistent primordial spectrum, which is not possible in the standard supercooled regime when inflation is driven by radiative corrections. |
2111.05848 | Oleksandr Sobol Dr. | E.V. Gorbar, A.I. Momot, I.V. Rudenok, O.O. Sobol, and S.I.
Vilchinskii | Chirality production during axion inflation | 13 pages, 2 figures. arXiv admin note: text overlap with
arXiv:2109.01651 | Ukrainian Journal of Physics, Vol. 68, No. 11, 717 (2023) | 10.15407/ujpe68.11.717 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the generation of the chiral charge during axion inflation where the
pseudoscalar inflaton field $\phi$ couples axially to the electromagnetic field
through the term $(\beta/M_p)\phi\,\boldsymbol{E}\cdot\boldsymbol{B}$ with
dimensionless coupling constant $\beta$. To describe the evolution of
electromagnetic field and determine
$\langle\boldsymbol{E}\cdot\boldsymbol{B}\rangle$ sourcing the chiral asymmetry
during inflation due to the chiral anomaly, we employ the gradient expansion
formalism. It operates with a set of vacuum expectation values of bilinear
electromagnetic functions and allows us to take into account the backreaction
of generated fields on the inflaton evolution as well as the Schwinger
production of charged fermions. In addition, we include the chiral magnetic
effect contribution to the electric current $\boldsymbol{j}_{\rm
CME}=e^{2}/(2\pi^2)\mu_{5}\boldsymbol{B}$, where $\mu_5$ is the chiral chemical
potential which quantifies the chiral charge production. Solving a set of
equations for the inflaton field, scale factor, quadratic functions of the
electromagnetic field, and the chiral charge density (chiral chemical
potential), we find that the chirality production is quite efficient leading to
the generation of a large chemical potential at the end of axion inflation.
| [
{
"created": "Wed, 10 Nov 2021 18:56:37 GMT",
"version": "v1"
}
] | 2024-04-03 | [
[
"Gorbar",
"E. V.",
""
],
[
"Momot",
"A. I.",
""
],
[
"Rudenok",
"I. V.",
""
],
[
"Sobol",
"O. O.",
""
],
[
"Vilchinskii",
"S. I.",
""
]
] | We study the generation of the chiral charge during axion inflation where the pseudoscalar inflaton field $\phi$ couples axially to the electromagnetic field through the term $(\beta/M_p)\phi\,\boldsymbol{E}\cdot\boldsymbol{B}$ with dimensionless coupling constant $\beta$. To describe the evolution of electromagnetic field and determine $\langle\boldsymbol{E}\cdot\boldsymbol{B}\rangle$ sourcing the chiral asymmetry during inflation due to the chiral anomaly, we employ the gradient expansion formalism. It operates with a set of vacuum expectation values of bilinear electromagnetic functions and allows us to take into account the backreaction of generated fields on the inflaton evolution as well as the Schwinger production of charged fermions. In addition, we include the chiral magnetic effect contribution to the electric current $\boldsymbol{j}_{\rm CME}=e^{2}/(2\pi^2)\mu_{5}\boldsymbol{B}$, where $\mu_5$ is the chiral chemical potential which quantifies the chiral charge production. Solving a set of equations for the inflaton field, scale factor, quadratic functions of the electromagnetic field, and the chiral charge density (chiral chemical potential), we find that the chirality production is quite efficient leading to the generation of a large chemical potential at the end of axion inflation. |
1212.1195 | Yuri V. Kovchegov | Yuri V. Kovchegov, Douglas E. Wertepny | Long-Range Rapidity Correlations in Heavy-Light Ion Collisions | 26 pages, 13 figurs; v2: some corrections and new figures included | null | 10.1016/j.nuclphysa.2013.03.006 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study two-particle long-range rapidity correlations arising in the early
stages of heavy ion collisions in the saturation/Color Glass Condensate
framework, assuming for simplicity that one colliding nucleus is much larger
than the other. We calculate the two-gluon production cross section while
including all-order saturation effects in the heavy nucleus with the
lowest-order rescattering in the lighter nucleus. We find four types of
correlations in the two-gluon production cross section: (i) geometric
correlations, (ii) HBT correlations accompanied by a back-to-back maximum,
(iii) away-side correlations, and (iv) near-side azimuthal correlations which
are long-range in rapidity. The geometric correlations (i) are due to the fact
that nucleons are correlated by simply being confined within the same nucleus
and may lead to long-range rapidity correlations for the produced particles
without strong azimuthal angle dependence. Somewhat surprisingly, long-range
rapidity correlations (iii) and (iv) have exactly the same amplitudes along
with azimuthal and rapidity shapes: one centered around \Delta \phi =\pi\ with
the other one centered around \Delta \phi =0 (here \Delta \phi\ is the
azimuthal angle between the two produced gluons). We thus observe that the
early-time CGC dynamics in nucleus-nucleus collisions generates azimuthal
non-flow correlations which are qualitatively different from jet correlations
by being long-range in rapidity. If strong enough, they have the potential of
mimicking the elliptic (and higher-order even-harmonic) flow in the di-hadron
correlators: one may need to take them into account in the experimental
determination of the flow observables.
| [
{
"created": "Wed, 5 Dec 2012 22:24:35 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Feb 2013 21:20:08 GMT",
"version": "v2"
}
] | 2015-06-12 | [
[
"Kovchegov",
"Yuri V.",
""
],
[
"Wertepny",
"Douglas E.",
""
]
] | We study two-particle long-range rapidity correlations arising in the early stages of heavy ion collisions in the saturation/Color Glass Condensate framework, assuming for simplicity that one colliding nucleus is much larger than the other. We calculate the two-gluon production cross section while including all-order saturation effects in the heavy nucleus with the lowest-order rescattering in the lighter nucleus. We find four types of correlations in the two-gluon production cross section: (i) geometric correlations, (ii) HBT correlations accompanied by a back-to-back maximum, (iii) away-side correlations, and (iv) near-side azimuthal correlations which are long-range in rapidity. The geometric correlations (i) are due to the fact that nucleons are correlated by simply being confined within the same nucleus and may lead to long-range rapidity correlations for the produced particles without strong azimuthal angle dependence. Somewhat surprisingly, long-range rapidity correlations (iii) and (iv) have exactly the same amplitudes along with azimuthal and rapidity shapes: one centered around \Delta \phi =\pi\ with the other one centered around \Delta \phi =0 (here \Delta \phi\ is the azimuthal angle between the two produced gluons). We thus observe that the early-time CGC dynamics in nucleus-nucleus collisions generates azimuthal non-flow correlations which are qualitatively different from jet correlations by being long-range in rapidity. If strong enough, they have the potential of mimicking the elliptic (and higher-order even-harmonic) flow in the di-hadron correlators: one may need to take them into account in the experimental determination of the flow observables. |
0807.1117 | David McGady | Thomas D. Cohen, and David A. McGady | The Schwinger mechanism revisited | 6 pages, 1 figure; References added, minor typos fixed | Phys.Rev.D78:036008,2008 | 10.1103/PhysRevD.78.036008 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The vacuum persistence probability, $P_{vac}(t)$, for a system of charged
fermions in a fixed, external, and spatially homogeneous electric field, was
derived long ago by Schwinger; $w = -log[P_{vac}(t)]/ (V t)$ has often been
identified as the rate at which fermion-antifermion pairs are produced per unit
volume due to the electric field. In this paper, we separately compute exact
expressions for both $w$ and for the rate of fermion-antifermion pair
production per unit volume, $\Gamma$, and show that they differ. While $w$ is
given by the standard Schwinger mechanism result $w$, an infinite series, the
pair production rate, $\Gamma$, is just the first term of that series. Our
calculation is done for a system with periodic boundary conditions in the
$A_0=0$ gauge but the result should hold for any consistent set of boundary
conditions. We discuss, the physical reason why the rates $w$ and $\Gamma$
differ.
| [
{
"created": "Mon, 7 Jul 2008 20:29:59 GMT",
"version": "v1"
},
{
"created": "Sat, 30 Aug 2008 21:25:48 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Cohen",
"Thomas D.",
""
],
[
"McGady",
"David A.",
""
]
] | The vacuum persistence probability, $P_{vac}(t)$, for a system of charged fermions in a fixed, external, and spatially homogeneous electric field, was derived long ago by Schwinger; $w = -log[P_{vac}(t)]/ (V t)$ has often been identified as the rate at which fermion-antifermion pairs are produced per unit volume due to the electric field. In this paper, we separately compute exact expressions for both $w$ and for the rate of fermion-antifermion pair production per unit volume, $\Gamma$, and show that they differ. While $w$ is given by the standard Schwinger mechanism result $w$, an infinite series, the pair production rate, $\Gamma$, is just the first term of that series. Our calculation is done for a system with periodic boundary conditions in the $A_0=0$ gauge but the result should hold for any consistent set of boundary conditions. We discuss, the physical reason why the rates $w$ and $\Gamma$ differ. |
1703.08677 | Xing-Gang Wu | Wei Cheng, Xing-Gang Wu, and Hai-Bing Fu | Reconsideration of the $B \to K^*$ Transition Form Factors within the
QCD Light-Cone Sum Rules | 17 pages, 6 figures. Discussions improved and references updated. To
be published in Phys.Rev.D | Phys. Rev. D 95, 094023 (2017) | 10.1103/PhysRevD.95.094023 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we study the $B \to K^*$ transition form factors (TFFs) within
the QCD light-cone sum rules (LCSR) approach. Two correlators, i.e. the usual
one and the right-handed one, are adopted in the LCSR calculation. The
resultant LCSRs for the $B \to K^*$ TFFs are arranged according to the twist
structure of the $K^*$-meson light-cone distribution amplitudes (LCDAs), whose
twist-2, twist-3 and twist-4 terms behave quite differently by using different
correlators. We observe that the twist-4 LCDAs, though generally small, shall
have sizable contributions to the TFFs $A_{1/2}$, $V$ and $T_1$, thus the
twist-4 terms should be kept for a sound prediction. We also observe that even
though different choices of the correlator lead to different LCSRs with
different twist contributions, the large correlation coefficients for most of
the TFFs indicate that the LCSRs for different correlators are close to each
order, not only for their values at the large recoil point $q^2=0$ but also for
their ascending trends in whole $q^2$-region. Such a high degree of correlation
is confirmed by their application to the branching fraction of the
semi-leptonic decay $B \to K^* \mu^+ \mu^-$. Thus, a proper choice of
correlator may inversely provide a chance for probing uncertain LCDAs, i.e. the
contributions from those LCDAs can be amplified to a certain degree via a
proper choice of correlator, thus amplifying the sensitivity of the TFFs, and
hence their related observables, to those LCDAs.
| [
{
"created": "Sat, 25 Mar 2017 11:40:55 GMT",
"version": "v1"
},
{
"created": "Tue, 9 May 2017 01:04:40 GMT",
"version": "v2"
}
] | 2017-06-01 | [
[
"Cheng",
"Wei",
""
],
[
"Wu",
"Xing-Gang",
""
],
[
"Fu",
"Hai-Bing",
""
]
] | In this paper, we study the $B \to K^*$ transition form factors (TFFs) within the QCD light-cone sum rules (LCSR) approach. Two correlators, i.e. the usual one and the right-handed one, are adopted in the LCSR calculation. The resultant LCSRs for the $B \to K^*$ TFFs are arranged according to the twist structure of the $K^*$-meson light-cone distribution amplitudes (LCDAs), whose twist-2, twist-3 and twist-4 terms behave quite differently by using different correlators. We observe that the twist-4 LCDAs, though generally small, shall have sizable contributions to the TFFs $A_{1/2}$, $V$ and $T_1$, thus the twist-4 terms should be kept for a sound prediction. We also observe that even though different choices of the correlator lead to different LCSRs with different twist contributions, the large correlation coefficients for most of the TFFs indicate that the LCSRs for different correlators are close to each order, not only for their values at the large recoil point $q^2=0$ but also for their ascending trends in whole $q^2$-region. Such a high degree of correlation is confirmed by their application to the branching fraction of the semi-leptonic decay $B \to K^* \mu^+ \mu^-$. Thus, a proper choice of correlator may inversely provide a chance for probing uncertain LCDAs, i.e. the contributions from those LCDAs can be amplified to a certain degree via a proper choice of correlator, thus amplifying the sensitivity of the TFFs, and hence their related observables, to those LCDAs. |
hep-ph/9706392 | Zvi Bern | Z. Bern, J. Rozowsky and B. Yan | Two-Loop N=4 Supersymmetric Amplitudes and QCD | Talk presented at 5th International Workshop on Deep Inelastic
Scattering and QCD, April 14-18, 1997, 5 pages | null | 10.1063/1.53686 | UCLA/97/TEP/13 | hep-ph | null | Two-loop four-gluon N=4 susy amplitudes are evaluated via cutting techniques
as a testing ground for QCD. A conjecture for four-point amplitudes to all loop
orders is described. We also present a new conjecture for the leading-color
part of the two-loop five-gluon amplitudes.
| [
{
"created": "Tue, 17 Jun 1997 19:13:48 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Bern",
"Z.",
""
],
[
"Rozowsky",
"J.",
""
],
[
"Yan",
"B.",
""
]
] | Two-loop four-gluon N=4 susy amplitudes are evaluated via cutting techniques as a testing ground for QCD. A conjecture for four-point amplitudes to all loop orders is described. We also present a new conjecture for the leading-color part of the two-loop five-gluon amplitudes. |
1109.6509 | Andreas Krassnigg | M. Blank and A. Krassnigg | Bottomonium in a Bethe-Salpeter-equation study | 6 pages, 4 figures, 2 tables | Phys.Rev.D84:096014,2011 | 10.1103/PhysRevD.84.096014 | null | hep-ph hep-ex hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using a well-established effective interaction in a rainbow-ladder truncation
model of QCD, we fix the remaining model parameter to the bottomonium
ground-state spectrum in a covariant Bethe-Salpeter equation approach and find
surprisingly good agreement with the available experimental data including the
2^{--} Upsilon(1D) state. Furthermore, we investigate the consequences of such
a fit for charmonium and light-quark ground states.
| [
{
"created": "Thu, 29 Sep 2011 12:46:57 GMT",
"version": "v1"
}
] | 2012-08-02 | [
[
"Blank",
"M.",
""
],
[
"Krassnigg",
"A.",
""
]
] | Using a well-established effective interaction in a rainbow-ladder truncation model of QCD, we fix the remaining model parameter to the bottomonium ground-state spectrum in a covariant Bethe-Salpeter equation approach and find surprisingly good agreement with the available experimental data including the 2^{--} Upsilon(1D) state. Furthermore, we investigate the consequences of such a fit for charmonium and light-quark ground states. |
2005.06492 | Veronica Sanz | Miguel G. Folgado, Veronica Sanz | On the interpretation of non-resonant phenomena at colliders | 10 pages, 9 figures | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | With null results in resonance searches at the LHC, the physics potential
focus is now shifting towards the interpretation of non-resonant phenomena. An
example of such shift is the increased popularity of the EFT programme. We can
embark on such programme owing to good integrated luminosity and an excellent
understanding of the detectors, which will allow these searches to become more
intense as the LHC continues. In this paper we provide a framework to perform
this interpretation in terms of a diverse set of scenarios, including {\it 1.)
} generic heavy new physics described at low energies in terms of a derivative
expansion, such as in the EFT approach, {\it 2.)} very light particles with
derivative couplings, such as axions or other light pseudo-Goldstone bosons,
and {\it 3.)} the effect of a quasi-continuum of resonances, which can come
from a number of strongly-coupled theories, extra-dimensional models, clockwork
set-ups and their deconstructed cousins. These scenarios are not equivalent
despite all non-resonant, although the matching among some of them is possible
and we provide it in this paper.
| [
{
"created": "Wed, 13 May 2020 18:01:17 GMT",
"version": "v1"
}
] | 2020-05-15 | [
[
"Folgado",
"Miguel G.",
""
],
[
"Sanz",
"Veronica",
""
]
] | With null results in resonance searches at the LHC, the physics potential focus is now shifting towards the interpretation of non-resonant phenomena. An example of such shift is the increased popularity of the EFT programme. We can embark on such programme owing to good integrated luminosity and an excellent understanding of the detectors, which will allow these searches to become more intense as the LHC continues. In this paper we provide a framework to perform this interpretation in terms of a diverse set of scenarios, including {\it 1.) } generic heavy new physics described at low energies in terms of a derivative expansion, such as in the EFT approach, {\it 2.)} very light particles with derivative couplings, such as axions or other light pseudo-Goldstone bosons, and {\it 3.)} the effect of a quasi-continuum of resonances, which can come from a number of strongly-coupled theories, extra-dimensional models, clockwork set-ups and their deconstructed cousins. These scenarios are not equivalent despite all non-resonant, although the matching among some of them is possible and we provide it in this paper. |
hep-ph/9212252 | Chengxing Zhai | Lowell S. Brown and Chengxing Zhai | 2 \to n threshold production at tree level | 14 pages in REVTEX, (Appendix removed) UW/PT-92-23 | Phys.Rev. D47 (1993) 5526-5530 | 10.1103/PhysRevD.47.5526 | null | hep-ph | null | The threshold behavior of a theory with two coupled scalar fields $\chi$ and
$\phi$ is investigated. We compute the amplitude for two on-mass-shell
$\chi$-particles to produce an arbitrary number of $\phi$-particles at rest in
the tree approximation.
| [
{
"created": "Thu, 10 Dec 1992 23:19:55 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Dec 1992 22:10:59 GMT",
"version": "v2"
}
] | 2009-10-22 | [
[
"Brown",
"Lowell S.",
""
],
[
"Zhai",
"Chengxing",
""
]
] | The threshold behavior of a theory with two coupled scalar fields $\chi$ and $\phi$ is investigated. We compute the amplitude for two on-mass-shell $\chi$-particles to produce an arbitrary number of $\phi$-particles at rest in the tree approximation. |
1507.05043 | Majid Monemzadeh Dr. | M. Monemzadeh, N. Tazimi, P. Sadeghi | Replies to Comments on "Tetraquarks as Diquark-Antidiquark Bound
Systems" | null | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The present paper is written in response to the critical comments of M.R.
Hadizadeh on our original paper Tetraquarks as diquark-antidiquark bound
systems [Phys. Lett. B 741, 124 (2015), arXiv:1505.07510]. We present our
clarifications on his arguments against the accuracy of the procedure and
results of the study. The arguments turn out to stem mainly from the critic's
misunderstanding of the issues discussed in the original paper.
| [
{
"created": "Wed, 8 Jul 2015 07:18:12 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Aug 2015 04:11:57 GMT",
"version": "v2"
}
] | 2015-08-05 | [
[
"Monemzadeh",
"M.",
""
],
[
"Tazimi",
"N.",
""
],
[
"Sadeghi",
"P.",
""
]
] | The present paper is written in response to the critical comments of M.R. Hadizadeh on our original paper Tetraquarks as diquark-antidiquark bound systems [Phys. Lett. B 741, 124 (2015), arXiv:1505.07510]. We present our clarifications on his arguments against the accuracy of the procedure and results of the study. The arguments turn out to stem mainly from the critic's misunderstanding of the issues discussed in the original paper. |
1501.05957 | Andre Lessa | Nayara Fonseca, Renata Zukanovich Funchal, Andre Lessa, Laura
Lopez-Honorez | Dark Matter Constraints on Composite Higgs Models | version accepted by JHEP | null | null | MIT-CTP 4623 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In composite Higgs models the pseudo-Nambu-Goldstone Boson (pNGB) nature of
the Higgs field is an interesting alternative for explaning the smallness of
the electroweak scale with respect to the beyond the Standard Model scale. In
non-minimal models additional pNGB states are present and can be a Dark Matter
(DM) candidate, if there is an approximate symmetry suppressing their decay.
Here we assume that the low energy effective theory (for scales much below the
compositeness scale) corresponds to the Standard Model with a pNGB Higgs
doublet and a pNGB DM multiplet. We derive general effective DM Lagrangians for
several possible DM representations (under the SM gauge group), including the
singlet, doublet and triplet cases. Within this framework we discuss how the DM
observables (relic abundance, direct and indirect detection) constrain the
dimension-6 operators induced by the strong sector assuming that DM behaves as
a Weakly Interacting Particle (WIMP) and that the relic abundance is settled
through the freeze-out mechanism. We also apply our general results to two
specific cosets: $SO(6)/SO(5)$ and $SO(6)/SO(4) \times SO(2)$, which contain a
singlet and doublet DM candidate, respectively. In particular we show that if
compositeness is a solution to the little hierarchy problem, representations
larger than the triplet are strongly disfavored. Furthermore, we find that
composite models can have viable DM candidates with much smaller direct
detection cross-sections than their non-composite counterparts, making DM
detection much more challenging.
| [
{
"created": "Fri, 23 Jan 2015 21:06:48 GMT",
"version": "v1"
},
{
"created": "Sat, 20 Jun 2015 21:29:53 GMT",
"version": "v2"
}
] | 2015-06-23 | [
[
"Fonseca",
"Nayara",
""
],
[
"Funchal",
"Renata Zukanovich",
""
],
[
"Lessa",
"Andre",
""
],
[
"Lopez-Honorez",
"Laura",
""
]
] | In composite Higgs models the pseudo-Nambu-Goldstone Boson (pNGB) nature of the Higgs field is an interesting alternative for explaning the smallness of the electroweak scale with respect to the beyond the Standard Model scale. In non-minimal models additional pNGB states are present and can be a Dark Matter (DM) candidate, if there is an approximate symmetry suppressing their decay. Here we assume that the low energy effective theory (for scales much below the compositeness scale) corresponds to the Standard Model with a pNGB Higgs doublet and a pNGB DM multiplet. We derive general effective DM Lagrangians for several possible DM representations (under the SM gauge group), including the singlet, doublet and triplet cases. Within this framework we discuss how the DM observables (relic abundance, direct and indirect detection) constrain the dimension-6 operators induced by the strong sector assuming that DM behaves as a Weakly Interacting Particle (WIMP) and that the relic abundance is settled through the freeze-out mechanism. We also apply our general results to two specific cosets: $SO(6)/SO(5)$ and $SO(6)/SO(4) \times SO(2)$, which contain a singlet and doublet DM candidate, respectively. In particular we show that if compositeness is a solution to the little hierarchy problem, representations larger than the triplet are strongly disfavored. Furthermore, we find that composite models can have viable DM candidates with much smaller direct detection cross-sections than their non-composite counterparts, making DM detection much more challenging. |
hep-ph/9909502 | null | A.A. Barrientos Bendezu and B.A. Kniehl | Quark-Loop Amplitudes for W^+- H^-+ Associated Hadroproduction | 6 pages (Latex) | Phys.Rev. D61 (2000) 097701 | 10.1103/PhysRevD.61.097701 | DESY 99-121 and KEK-TH-638 | hep-ph | null | In this addendum to our paper entitled "W^+- H^-+ Associated Production at
the Large Hadron Collider" [Phys. Rev. D 59, 015009 (1999)], we list analytic
results for the helicity amplitudes of the partonic subprocess gg -> W^-H^+
induced by virtual quarks.
| [
{
"created": "Fri, 24 Sep 1999 15:17:16 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Bendezu",
"A. A. Barrientos",
""
],
[
"Kniehl",
"B. A.",
""
]
] | In this addendum to our paper entitled "W^+- H^-+ Associated Production at the Large Hadron Collider" [Phys. Rev. D 59, 015009 (1999)], we list analytic results for the helicity amplitudes of the partonic subprocess gg -> W^-H^+ induced by virtual quarks. |
2111.08225 | Lata Thakur | Lata Thakur, Yuji Hirono | Spectral functions of heavy quarkonia in a bulk-viscous quark gluon
plasma | 28 pages, 16 figures, v2, published version | JHEP 02 (2022) 207 | 10.1007/JHEP02(2022)207 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the properties of quarkonia inside a bulk-viscous quark gluon
plasma. The non-equilibrium nature of the medium is encoded in the deformed
distribution functions of thermal quarks and gluons, with which we compute the
dielectric permittivity within the hard thermal loop approximation at one-loop.
The modified dielectric permittivity is used to calculate the in-medium heavy
quark potential, and using the potential we compute spectral functions, which
reflect the physical properties of heavy quarkonia. We discuss how the bulk
viscous effect influences quantities such as binding energies and thermal
widths. Based on those properties, we discuss the implications of the bulk
viscous effect on the physical observables such as $ \psi' $ to $ J/\psi $
ratio and the nuclear modification factor, $R_{AA}$. In particular, we argue
that the nuclear modification factors of excited and ground states show
different sensitivities to the bulk viscous nature of a plasma, which is
potentially useful for the critical point search.
| [
{
"created": "Tue, 16 Nov 2021 04:50:40 GMT",
"version": "v1"
},
{
"created": "Wed, 2 Mar 2022 08:11:47 GMT",
"version": "v2"
}
] | 2022-03-03 | [
[
"Thakur",
"Lata",
""
],
[
"Hirono",
"Yuji",
""
]
] | We study the properties of quarkonia inside a bulk-viscous quark gluon plasma. The non-equilibrium nature of the medium is encoded in the deformed distribution functions of thermal quarks and gluons, with which we compute the dielectric permittivity within the hard thermal loop approximation at one-loop. The modified dielectric permittivity is used to calculate the in-medium heavy quark potential, and using the potential we compute spectral functions, which reflect the physical properties of heavy quarkonia. We discuss how the bulk viscous effect influences quantities such as binding energies and thermal widths. Based on those properties, we discuss the implications of the bulk viscous effect on the physical observables such as $ \psi' $ to $ J/\psi $ ratio and the nuclear modification factor, $R_{AA}$. In particular, we argue that the nuclear modification factors of excited and ground states show different sensitivities to the bulk viscous nature of a plasma, which is potentially useful for the critical point search. |
1708.02649 | Diego Guadagnoli | Diego Guadagnoli, Meril Reboud and Roman Zwicky | $B^0_s \to \ell^+ \ell^- \gamma$ as a Test of Lepton Flavor Universality | 21 pages, 4 figures. v4: in appendix removed equation already present
in main text | JHEP11(2017)184 | 10.1007/JHEP11(2017)184 | LAPTH-025/17, ZU-TH 23/17, CP3-Origins-2017-030 DNRF90 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss a number of strategies to reduce the $\mathcal B(B^0_s \to
\ell^{+} \ell^{-} \gamma)$ theoretical error, and make such a measurement a new
probe of the interactions that are interesting in the light of present-day
flavor discrepancies. In particular, for low di-lepton invariant mass we
propose to exploit the close parenthood between $\mathcal B(B^0_s \to \ell^{+}
\ell^{-} \gamma)$ and the measured $\mathcal B(B^0_s \to \phi (\to K^+ K^-)
\gamma)$. For high $q^2$, conversely, we exploit the fact that the decay is
dominated by two form-factor combinations, plus contributions from broad
charmonium that we model accordingly. We construct the ratio $R_\gamma$, akin
to $R_K$ and likewise sensitive to lepton-universality violation. Provided the
two rates in this ratio are integrated in a suitable region that minimises
bremsstrahlung contributions while maximising statistics, the ratio is very
close to unity and the form-factor dependence cancels to an extent that makes
it a new valuable probe of lepton-universality violating contributions in the
effective Hamiltonian. We finally speculate on additional ideas to extract
short-distance information from resonance regions, which are theoretically
interesting but statistically limited at present.
| [
{
"created": "Tue, 8 Aug 2017 20:51:32 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Sep 2017 19:33:45 GMT",
"version": "v2"
},
{
"created": "Thu, 14 Dec 2017 08:40:34 GMT",
"version": "v3"
},
{
"created": "Wed, 8 Aug 2018 09:07:24 GMT",
"version": "v4"
}
] | 2018-08-09 | [
[
"Guadagnoli",
"Diego",
""
],
[
"Reboud",
"Meril",
""
],
[
"Zwicky",
"Roman",
""
]
] | We discuss a number of strategies to reduce the $\mathcal B(B^0_s \to \ell^{+} \ell^{-} \gamma)$ theoretical error, and make such a measurement a new probe of the interactions that are interesting in the light of present-day flavor discrepancies. In particular, for low di-lepton invariant mass we propose to exploit the close parenthood between $\mathcal B(B^0_s \to \ell^{+} \ell^{-} \gamma)$ and the measured $\mathcal B(B^0_s \to \phi (\to K^+ K^-) \gamma)$. For high $q^2$, conversely, we exploit the fact that the decay is dominated by two form-factor combinations, plus contributions from broad charmonium that we model accordingly. We construct the ratio $R_\gamma$, akin to $R_K$ and likewise sensitive to lepton-universality violation. Provided the two rates in this ratio are integrated in a suitable region that minimises bremsstrahlung contributions while maximising statistics, the ratio is very close to unity and the form-factor dependence cancels to an extent that makes it a new valuable probe of lepton-universality violating contributions in the effective Hamiltonian. We finally speculate on additional ideas to extract short-distance information from resonance regions, which are theoretically interesting but statistically limited at present. |
hep-ph/9703204 | A. A. Penin | N.V.Krasnikov and V.A.Matveev | Physics at LHC | 82 pages | Phys.Part.Nucl.28:441-470,1997; Fiz.Elem.Chast.Atom.Yadra
28:1125-1189,1997 | 10.1134/1.953049 | Preprint INR 0940/97 | hep-ph | null | We review the physics to be investigated at LHC. We also describe the main
parameters of CMS and ATLAS detectors.
| [
{
"created": "Fri, 28 Feb 1997 10:53:43 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Krasnikov",
"N. V.",
""
],
[
"Matveev",
"V. A.",
""
]
] | We review the physics to be investigated at LHC. We also describe the main parameters of CMS and ATLAS detectors. |
hep-ph/0502196 | Danny Marfatia | V. Barger, Patrick Huber, Danny Marfatia | Solar mass-varying neutrino oscillations | 4 pages, 3 figures. Version to appear in PRL | Phys.Rev.Lett.95:211802,2005 | 10.1103/PhysRevLett.95.211802 | null | hep-ph astro-ph gr-qc hep-ex nucl-ex nucl-th | null | We propose that the solar neutrino deficit may be due to oscillations of
mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data
beautifully while remaining comfortably compatible with atmospheric neutrino
and K2K data and with reactor antineutrino data at short and long baselines
(from CHOOZ and KamLAND). We find that the survival probability of solar MaVaNs
is independent of how the suppression of neutrino mass caused by the
acceleron-matter couplings varies with density. Measurements of MeV and lower
energy solar neutrinos will provide a rigorous test of the idea.
| [
{
"created": "Mon, 21 Feb 2005 19:59:20 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Sep 2005 21:30:33 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Barger",
"V.",
""
],
[
"Huber",
"Patrick",
""
],
[
"Marfatia",
"Danny",
""
]
] | We propose that the solar neutrino deficit may be due to oscillations of mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data beautifully while remaining comfortably compatible with atmospheric neutrino and K2K data and with reactor antineutrino data at short and long baselines (from CHOOZ and KamLAND). We find that the survival probability of solar MaVaNs is independent of how the suppression of neutrino mass caused by the acceleron-matter couplings varies with density. Measurements of MeV and lower energy solar neutrinos will provide a rigorous test of the idea. |
hep-ph/0604066 | Martin Schmaltz | Adam Falkowski, Stefan Pokorski and Martin Schmaltz | Twin SUSY | 10 pages; v2: references and Lawrence added | Phys.Rev. D74 (2006) 035003 | 10.1103/PhysRevD.74.035003 | CERN-PH-TH/2006-051, BUHEP-06-05 | hep-ph hep-th | null | We construct an extension of the MSSM in which superpartners can naturally be
heavier than the electroweak scale. This ``little hierarchy'' of scales is
stable because the Higgs arises as a pseudo-Nambu-Goldstone boson in the
breaking of an accidental SU(4) symmetry of the Higgs sector. Supersymmetry and
the global symmetry combine to forbid logarithmically divergent one-loop
contributions to the Higgs mass. The accidental symmetry follows from a simple
``twin'' parity which exchanges the SU(2) sectors in the SU(3)_C x SU(2)_L x
SU(2)_R x U(1)_X gauge group.
| [
{
"created": "Fri, 7 Apr 2006 19:47:45 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Apr 2006 18:39:47 GMT",
"version": "v2"
},
{
"created": "Sat, 22 Apr 2006 18:04:15 GMT",
"version": "v3"
}
] | 2009-11-11 | [
[
"Falkowski",
"Adam",
""
],
[
"Pokorski",
"Stefan",
""
],
[
"Schmaltz",
"Martin",
""
]
] | We construct an extension of the MSSM in which superpartners can naturally be heavier than the electroweak scale. This ``little hierarchy'' of scales is stable because the Higgs arises as a pseudo-Nambu-Goldstone boson in the breaking of an accidental SU(4) symmetry of the Higgs sector. Supersymmetry and the global symmetry combine to forbid logarithmically divergent one-loop contributions to the Higgs mass. The accidental symmetry follows from a simple ``twin'' parity which exchanges the SU(2) sectors in the SU(3)_C x SU(2)_L x SU(2)_R x U(1)_X gauge group. |
hep-ph/0410343 | Kang Young Lee | C.S. Kim (Yonsei U.), Yeong Gyun Kim (Korea U.), and Kang Young Lee
(KAIST) | Time dependent CP asymmetry in $B^0 \to \rho^0 \gamma$ decay to probe
the origin of CP violation | 10 pages, 4 eps figures | Phys.Rev. D71 (2005) 054014 | 10.1103/PhysRevD.71.054014 | KAIST-TH 2004/18 | hep-ph | null | Since the CP violation in the $B$ system has been investigated up to now only
through processes related to the $B$--$\bar{B}$ mixing, urgently required is
new way of study for the CP violation and establishing its origin in the $B$
system independent of the mixing process. In this work, we explore the
exclusive $ B^0 \to \rho^0 \gamma$ decay to obtain the time-dependent CP
asymmetry in $b \to d$ decay process in the standard model and the
supersymmetric model. We find that the complex RL and RR mass insertion to the
squark sector in the MSSM can lead to a large CP asymmetry in $b \to d \gamma$
decay through the gluino-squark diagrams, which is not predicted in the
Standard Model induced by the $B$--$\bar{B}$ mixing.
| [
{
"created": "Tue, 26 Oct 2004 12:37:06 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Kim",
"C. S.",
"",
"Yonsei U."
],
[
"Kim",
"Yeong Gyun",
"",
"Korea U."
],
[
"Lee",
"Kang Young",
"",
"KAIST"
]
] | Since the CP violation in the $B$ system has been investigated up to now only through processes related to the $B$--$\bar{B}$ mixing, urgently required is new way of study for the CP violation and establishing its origin in the $B$ system independent of the mixing process. In this work, we explore the exclusive $ B^0 \to \rho^0 \gamma$ decay to obtain the time-dependent CP asymmetry in $b \to d$ decay process in the standard model and the supersymmetric model. We find that the complex RL and RR mass insertion to the squark sector in the MSSM can lead to a large CP asymmetry in $b \to d \gamma$ decay through the gluino-squark diagrams, which is not predicted in the Standard Model induced by the $B$--$\bar{B}$ mixing. |
hep-ph/9906223 | Daniel Boer | Daniel Boer (RIKEN-BNL Research Center, Brookhaven) and P.J. Mulders
(Free University, Amsterdam) | Color gauge invariance in the Drell-Yan process | 16 pages, Revtex, 2 Postscript figures, uses aps.sty, epsf.sty; error
in revision removed | Nucl.Phys. B569 (2000) 505-526 | 10.1016/S0550-3213(99)00719-1 | RIKEN-BNL preprint, VUTH 99-12 | hep-ph | null | We consider the color gauge invariance of a factorized description of the
Drell-Yan process cross section. In particular, we focus on the next-to-leading
twist contributions for polarized scattering and on the cross section
differential in the transverse momentum of the lepton pair in the region where
the transverse momentum is small compared to the hard scale. The hadron tensor
is expressed in terms of manifestly color gauge invariant, nonlocal operator
matrix elements and a color gauge invariant treatment of soft gluon poles is
given. Also, we clarify the discrepancy between two published results for a
single spin asymmetry in the Drell-Yan cross section. This asymmetry arises if
such a soft gluon pole is present in a specific twist-three hadronic matrix
element.
| [
{
"created": "Wed, 2 Jun 1999 21:16:33 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Sep 1999 21:10:17 GMT",
"version": "v2"
},
{
"created": "Mon, 22 Nov 1999 16:03:50 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Boer",
"Daniel",
"",
"RIKEN-BNL Research Center, Brookhaven"
],
[
"Mulders",
"P. J.",
"",
"Free University, Amsterdam"
]
] | We consider the color gauge invariance of a factorized description of the Drell-Yan process cross section. In particular, we focus on the next-to-leading twist contributions for polarized scattering and on the cross section differential in the transverse momentum of the lepton pair in the region where the transverse momentum is small compared to the hard scale. The hadron tensor is expressed in terms of manifestly color gauge invariant, nonlocal operator matrix elements and a color gauge invariant treatment of soft gluon poles is given. Also, we clarify the discrepancy between two published results for a single spin asymmetry in the Drell-Yan cross section. This asymmetry arises if such a soft gluon pole is present in a specific twist-three hadronic matrix element. |
2107.04858 | Zi-Qiang Chen | Zi-Qiang Chen, Qi-Ming Feng, and Cong-Feng Qiao | NLO EW corrections to Higgs boson decay to a lepton pair and a polarized
$Z$ boson | 23 pages, 5 figures, with substantial improvements | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we calculate the next-to-leading order electroweak corrections
to the process $H\to e^+e^-Z\to e^+e^-\mu^+\mu^-$ in the framework of
single-pole approximation, in which the contributions of intermediate $Z$ boson
in different polarizations are considered respectively. The total and
differential decay widths versus various kinematic variables are presented.
Phenomenologically, the corresponding cross sections in the experiment of Large
Hadron Collider (LHC) are evaluated.
| [
{
"created": "Sat, 10 Jul 2021 15:17:02 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Sep 2022 00:46:05 GMT",
"version": "v2"
}
] | 2022-09-30 | [
[
"Chen",
"Zi-Qiang",
""
],
[
"Feng",
"Qi-Ming",
""
],
[
"Qiao",
"Cong-Feng",
""
]
] | In this paper, we calculate the next-to-leading order electroweak corrections to the process $H\to e^+e^-Z\to e^+e^-\mu^+\mu^-$ in the framework of single-pole approximation, in which the contributions of intermediate $Z$ boson in different polarizations are considered respectively. The total and differential decay widths versus various kinematic variables are presented. Phenomenologically, the corresponding cross sections in the experiment of Large Hadron Collider (LHC) are evaluated. |
1705.03685 | Alan D. Martin | V.A. Khoze, A.D. Martin and M.G. Ryskin | Total $\pi^+ p$ cross section extracted from the leading neutron spectra
at the LHC | 21 pages, 6 figures, text improved, version to be published in Phys.
Rev. D | Phys. Rev. D 96, 034018 (2017) | 10.1103/PhysRevD.96.034018 | IPPP/17/35 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use the very forward neutron energy spectra measured by the Large Hadron
Collider forward (LHCf) experiment at 7 TeV to extract the $\pi^+ p$ total
cross section at centre-of-mass energies in the range 2.3$-$3.5 TeV. To do this
we have to first isolate the $\pi$-exchange pole in forward neutron production
in $pp$ collisions, by evaluating other possible contributions. Namely, those
from $\rho$ and $a_2$ exchange, from both eikonal and enhanced screening
effects, from migration, from neutron production by $\Delta$-isobar decay and
from diffractive nucleon excitations. We discuss the possible theoretical
uncertainties due to the fact that the data do not exactly reach the $\pi$
pole. We choose the kinematical domain where the pion contribution dominates
and demonstrate the role of the different corrections which could affect the
final result.
| [
{
"created": "Wed, 10 May 2017 10:21:26 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Aug 2017 09:46:56 GMT",
"version": "v2"
}
] | 2017-08-30 | [
[
"Khoze",
"V. A.",
""
],
[
"Martin",
"A. D.",
""
],
[
"Ryskin",
"M. G.",
""
]
] | We use the very forward neutron energy spectra measured by the Large Hadron Collider forward (LHCf) experiment at 7 TeV to extract the $\pi^+ p$ total cross section at centre-of-mass energies in the range 2.3$-$3.5 TeV. To do this we have to first isolate the $\pi$-exchange pole in forward neutron production in $pp$ collisions, by evaluating other possible contributions. Namely, those from $\rho$ and $a_2$ exchange, from both eikonal and enhanced screening effects, from migration, from neutron production by $\Delta$-isobar decay and from diffractive nucleon excitations. We discuss the possible theoretical uncertainties due to the fact that the data do not exactly reach the $\pi$ pole. We choose the kinematical domain where the pion contribution dominates and demonstrate the role of the different corrections which could affect the final result. |
hep-ph/9502415 | J. Wudka | Bohdan Grzadkowski and Jose Wudka | Higgs boson production at $e^+ e^-$ colliders: a model independent
approach. | plain LaTeX, requires epsf.tex, figures included in a uuencoded file
at the end | Phys.Lett. B364 (1995) 49-54 | 10.1016/0370-2693(95)01184-1 | IFT-25/94, UCR-T133 | hep-ph | null | We consider non-Standard Model physics effects using an effective lagrangian
parameterization. We determine the operators whose effects are most significant
and extract the sensitivity to the scale of new physics generated by the
existing data. We then consider processes containing the Higgs particle in
$e^+e^-$ colliders as a probe for new physics effects, and demonstrate their
usefulness in this area.
| [
{
"created": "Tue, 28 Feb 1995 17:09:01 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Grzadkowski",
"Bohdan",
""
],
[
"Wudka",
"Jose",
""
]
] | We consider non-Standard Model physics effects using an effective lagrangian parameterization. We determine the operators whose effects are most significant and extract the sensitivity to the scale of new physics generated by the existing data. We then consider processes containing the Higgs particle in $e^+e^-$ colliders as a probe for new physics effects, and demonstrate their usefulness in this area. |
2106.11045 | Qi-Fang L\"u | Hui-Zhen He, Wei Liang, Qi-Fang L\"u | Strong decays of the low-lying doubly bottom baryons | 12 pages, 4 figures. Some discussions are added, accepted version | null | 10.1103/PhysRevD.105.014010 | null | hep-ph hep-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | In this work, we adopt the $^3P_0$ model to investigate the strong decays of
the low-lying doubly bottom baryons in the $j-j$ coupling scheme
systematically. In this scheme, we construct the formulism of $^3P_0$ model
under the spectator assumption, and then the heavy diquark symmetry is
preserved automatically. Our results show that some of the $\lambda$-mode
$\Xi_{bb}(1P)$ and $\Omega_{bb}(1P)$ states are narrow, which have good
potentials to be observed by future experiments. For the low-lying $\rho$-mode
and $\rho$-$\lambda$ hybrid states, the Okubo-Zweig-Iizuka-allowed strong
decays are highly suppressed and they should be extremely narrow. Future
experiments can test our phenomenological predictions at the quark level.
| [
{
"created": "Mon, 21 Jun 2021 12:31:41 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Dec 2021 09:04:50 GMT",
"version": "v2"
}
] | 2022-01-19 | [
[
"He",
"Hui-Zhen",
""
],
[
"Liang",
"Wei",
""
],
[
"Lü",
"Qi-Fang",
""
]
] | In this work, we adopt the $^3P_0$ model to investigate the strong decays of the low-lying doubly bottom baryons in the $j-j$ coupling scheme systematically. In this scheme, we construct the formulism of $^3P_0$ model under the spectator assumption, and then the heavy diquark symmetry is preserved automatically. Our results show that some of the $\lambda$-mode $\Xi_{bb}(1P)$ and $\Omega_{bb}(1P)$ states are narrow, which have good potentials to be observed by future experiments. For the low-lying $\rho$-mode and $\rho$-$\lambda$ hybrid states, the Okubo-Zweig-Iizuka-allowed strong decays are highly suppressed and they should be extremely narrow. Future experiments can test our phenomenological predictions at the quark level. |
hep-ph/9603306 | Gabriel Sanchez Colon | A. Garcia (1), R. Huerta (2), and G. Sanchez-Colon (2,3) ((1)
CINVESTAV-Mexico, (2) CINVESTAV-Merida, (3) UC-Riverside) | Hyperon Non-leptonic Decays, the |Delta I|=1/2 Rule, and A Priori Mixed
Hadrons | Submitted to Rev. Mex. Fis | Rev.Mex.Fis. 45 (1999) 244-248 | null | LE-6129 | hep-ph | null | The $|\Delta I|=1/2$ rule in non-leptonic decays of hyperons can be naturally
understood by postulating a priori mixed physical hadrons, along with the
isospin invariance of the responsible transition operator. It is shown that
this operator can be identified with the strong interaction Yukawa hamiltonian.
The experimental amplitudes are well reproduced.
| [
{
"created": "Wed, 13 Mar 1996 18:39:11 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Apr 1998 01:12:24 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Garcia",
"A.",
""
],
[
"Huerta",
"R.",
""
],
[
"Sanchez-Colon",
"G.",
""
]
] | The $|\Delta I|=1/2$ rule in non-leptonic decays of hyperons can be naturally understood by postulating a priori mixed physical hadrons, along with the isospin invariance of the responsible transition operator. It is shown that this operator can be identified with the strong interaction Yukawa hamiltonian. The experimental amplitudes are well reproduced. |
1204.5502 | Alfredo Valcarce | T. F. Carames, A. Valcarce | $N\bar D $ system: A challenge for $\bar {\rm P}$ANDA | 16 pages, 15 figures, accepted for publication in Phys. Rev. D | Phys. Rev. D 85, 094017 (1-10), 2012 | 10.1103/PhysRevD.85.094017 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the $N \bar D$ system by means of a chiral constituent quark model.
This model, tuned in the description of the baryon and meson spectra as well as
the $NN$ interaction, provides parameter-free predictions for the charm -1
two-hadron systems. The presence of a heavy antiquark makes the interaction
rather simple. We have found sharp quark-Pauli effects in some particular
channels, generating repulsion, due to lacking degrees of freedom to
accommodate the light quarks. Our results point to the existence of an
attractive state, the $\Delta \bar D^*$ with $(T,S)=(1,5/2)$, presenting a
resonance close to threshold. It would show up in the scattering of $\bar D$
mesons on nucleons as a D wave state with quantum numbers $(T)J^P=(1)5/2^-$.
This resonance resembles our findings in the $\Delta\Delta$ system, that
offered a plausible explanation to the cross section of double-pionic fusion
reactions through the so-called {\it ABC} effect. The study of the interaction
of $D$ mesons with nucleons is a goal of the $\bar {\rm P}$ANDA Collaboration
at the European facility FAIR and, thus, the present theoretical study is a
challenge to be tested at the future experiments.
| [
{
"created": "Tue, 24 Apr 2012 22:03:16 GMT",
"version": "v1"
}
] | 2012-05-21 | [
[
"Carames",
"T. F.",
""
],
[
"Valcarce",
"A.",
""
]
] | We study the $N \bar D$ system by means of a chiral constituent quark model. This model, tuned in the description of the baryon and meson spectra as well as the $NN$ interaction, provides parameter-free predictions for the charm -1 two-hadron systems. The presence of a heavy antiquark makes the interaction rather simple. We have found sharp quark-Pauli effects in some particular channels, generating repulsion, due to lacking degrees of freedom to accommodate the light quarks. Our results point to the existence of an attractive state, the $\Delta \bar D^*$ with $(T,S)=(1,5/2)$, presenting a resonance close to threshold. It would show up in the scattering of $\bar D$ mesons on nucleons as a D wave state with quantum numbers $(T)J^P=(1)5/2^-$. This resonance resembles our findings in the $\Delta\Delta$ system, that offered a plausible explanation to the cross section of double-pionic fusion reactions through the so-called {\it ABC} effect. The study of the interaction of $D$ mesons with nucleons is a goal of the $\bar {\rm P}$ANDA Collaboration at the European facility FAIR and, thus, the present theoretical study is a challenge to be tested at the future experiments. |
1807.07972 | Anirudh Krovi | Anirudh Krovi, Ian Low, Yue Zhang | Broadening Dark Matter Searches at the LHC: Mono-X versus Darkonium
Channels | 24 pages, 8 figures, v2: more references added | null | 10.1007/JHEP10(2018)026 | CERN-TH-2018-169, FERMILAB-PUB-18-326-T | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | Current searches for dark matter at the LHC focus on mono-X signatures: the
production of dark matter in association with a Standard Model (SM) particle.
The simplest benchmark introduces a massive spin-1 mediator, the $Z^\prime$
boson, between the dark matter $\chi$ and the SM. Limits derived from mono-X
channels are most effective when the mediator can decay into two on-shell dark
matter particles: $M_{Z'}\gtrsim 2M_\chi$. We broaden the experimental reach
into the complementary region, where the $Z^\prime$ mediator is much lighter
than the dark matter. In this scenario the $Z^\prime$ mediates an effective
long-range force between the dark matter, thereby facilitating the formation of
darkonium bound states, as is common in many dark sector models. The darkonium
becomes active when $M_{\chi}>M_{Z'}/\alpha_{\rm eff}$, where $\alpha_{\rm
eff}$ is the effective fine-structure constant in the dark sector. Moreover,
the darkonium could decay back into SM quarks, without producing missing
transverse momentum in the detector. Considering multijet final states, we
reinterpret existing searches to constrain the simple $Z^\prime$ benchmark
beyond the region probed by mono-X searches. Assuming a baryonic $Z^\prime$
mediator and a Dirac dark matter, direct detection bounds can be loosened by
giving a small Majorana mass to the dark matter. We also consider the interplay
between mono-X and darkonium channels at future high energy colliders, which is
at the frontier of probing the model parameter space.
| [
{
"created": "Fri, 20 Jul 2018 18:00:02 GMT",
"version": "v1"
},
{
"created": "Thu, 13 Dec 2018 04:24:35 GMT",
"version": "v2"
}
] | 2018-12-14 | [
[
"Krovi",
"Anirudh",
""
],
[
"Low",
"Ian",
""
],
[
"Zhang",
"Yue",
""
]
] | Current searches for dark matter at the LHC focus on mono-X signatures: the production of dark matter in association with a Standard Model (SM) particle. The simplest benchmark introduces a massive spin-1 mediator, the $Z^\prime$ boson, between the dark matter $\chi$ and the SM. Limits derived from mono-X channels are most effective when the mediator can decay into two on-shell dark matter particles: $M_{Z'}\gtrsim 2M_\chi$. We broaden the experimental reach into the complementary region, where the $Z^\prime$ mediator is much lighter than the dark matter. In this scenario the $Z^\prime$ mediates an effective long-range force between the dark matter, thereby facilitating the formation of darkonium bound states, as is common in many dark sector models. The darkonium becomes active when $M_{\chi}>M_{Z'}/\alpha_{\rm eff}$, where $\alpha_{\rm eff}$ is the effective fine-structure constant in the dark sector. Moreover, the darkonium could decay back into SM quarks, without producing missing transverse momentum in the detector. Considering multijet final states, we reinterpret existing searches to constrain the simple $Z^\prime$ benchmark beyond the region probed by mono-X searches. Assuming a baryonic $Z^\prime$ mediator and a Dirac dark matter, direct detection bounds can be loosened by giving a small Majorana mass to the dark matter. We also consider the interplay between mono-X and darkonium channels at future high energy colliders, which is at the frontier of probing the model parameter space. |
0912.1417 | Sergey Goloskokov | S.V.Goloskokov | GPDs and spin effects in light mesons production | 8 pages, 14 figs, report at the Advanced Studies Institute Symmetries
And Spin (SPIN-Praha-2009) Prague, July 26 - August 2, 2009 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Light meson electroproduction is analyzed on the basis of the handbag
approach. Our results on the cross section and spin effects are in good
agrement with experiments at HERA, COMPASS and HERMES energies. Predictions for
$A_{UT}$ asymmetry for various reactions are presented.
| [
{
"created": "Tue, 8 Dec 2009 07:11:03 GMT",
"version": "v1"
}
] | 2009-12-09 | [
[
"Goloskokov",
"S. V.",
""
]
] | Light meson electroproduction is analyzed on the basis of the handbag approach. Our results on the cross section and spin effects are in good agrement with experiments at HERA, COMPASS and HERMES energies. Predictions for $A_{UT}$ asymmetry for various reactions are presented. |
hep-ph/9512321 | Kimmo Kainulainen | Brian D. Fields, Kimmo Kainulainen and Keith A. Olive | Nucleosynthesis Limits on the Mass of Long Lived Tau and Muon Neutrinos | 29 pages, 6 eps-figures, uses epsf.sty | Astropart.Phys.6:169-186,1997 | 10.1016/S0927-6505(96)00052-7 | CERN-TH/95-335, UMN-TH-1417/95 | hep-ph astro-ph | null | We compute the nucleosynthesis bounds on the masses of stable Dirac and
Majorana neutrinos by solving an evolution equation network comprising of all
neutrino species which in the Dirac case includes different helicity states as
separate species. We will not commit ourselves to any particular value of the
nucleosynthesis bound on effective number of light neutrino degrees of freedom
$N_\nu$, but present all our mass bounds as {\em functions} of $\dNu$. For
example, we find that the excluded region in the mass of a Majorana $\mu$- or
$\tau$- neutrino, $0.31$ MeV $< m_{\nu}^M < 52$ MeV corresponding to a bound
$\dNu < 0.3$ gets relaxed to $0.93$ MeV $< m_{\nu}^M < 31$ MeV if $\dNu < 1.0$
is used instead. For the Dirac neutrinos this latter constraint gives the upper
limits (for $T_{\rm QCD} = 100$ MeV): $\mnm < 0.31$ MeV and $\mnt < 0.37$ MeV.
Also, the constraint $\dNu <1$ {\it allows} a stable Dirac neutrino with
$m^D_{\nu_\tau} > 22$ MeV.
| [
{
"created": "Fri, 15 Dec 1995 09:01:21 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Fields",
"Brian D.",
""
],
[
"Kainulainen",
"Kimmo",
""
],
[
"Olive",
"Keith A.",
""
]
] | We compute the nucleosynthesis bounds on the masses of stable Dirac and Majorana neutrinos by solving an evolution equation network comprising of all neutrino species which in the Dirac case includes different helicity states as separate species. We will not commit ourselves to any particular value of the nucleosynthesis bound on effective number of light neutrino degrees of freedom $N_\nu$, but present all our mass bounds as {\em functions} of $\dNu$. For example, we find that the excluded region in the mass of a Majorana $\mu$- or $\tau$- neutrino, $0.31$ MeV $< m_{\nu}^M < 52$ MeV corresponding to a bound $\dNu < 0.3$ gets relaxed to $0.93$ MeV $< m_{\nu}^M < 31$ MeV if $\dNu < 1.0$ is used instead. For the Dirac neutrinos this latter constraint gives the upper limits (for $T_{\rm QCD} = 100$ MeV): $\mnm < 0.31$ MeV and $\mnt < 0.37$ MeV. Also, the constraint $\dNu <1$ {\it allows} a stable Dirac neutrino with $m^D_{\nu_\tau} > 22$ MeV. |
2006.12164 | Avirup Shaw | Avirup Shaw | The impact of nonminimal Universal Extra Dimensional model on $\Delta
B=2$ transitions | A table added, some clarifying remarks added and version accepted for
publication in The European Physical Journal C | Eur. Phys. J. C (2021) 81:137 | 10.1140/epjc/s10052-021-08937-9 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We measure the impact of nonvanishing boundary localised terms on $\Delta
B=2$ transitions in five-dimensional Universal Extra Dimensional scenario where
masses and coupling strengths of several interactions of Kaluza-Klein modes are
significantly modified with respect to the minimal counterpart. In such
scenario we estimate the Kaluza-Klein contributions of quarks, gauge bosons and
charged Higgs by evaluating the one-loop box diagrams that are responsible for
the $\Delta B=2$ transitions. Using the loop function (obtained from one-loop
box diagrams) we determine several important elements that are involved in
Wolfenstein parametrisation. Moreover, with these elements we also study the
geometrical shape of unitarity triangle. Besides, we compute the quantity
$\Delta M_s$ scaled by the corresponding Standard Model value. Outcomes of our
theoretical predictions have been compared to the allowed ranges of the
corresponding observables simultaneously. Our current analysis shows that,
depending on the parameters in this scenario the lower limit on the inverse of
the radius of compactification can reach to an appreciable large value
($\approx 1.48$ TeV or even higher).
| [
{
"created": "Mon, 22 Jun 2020 11:54:24 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Jun 2020 12:48:11 GMT",
"version": "v2"
},
{
"created": "Tue, 2 Feb 2021 05:57:29 GMT",
"version": "v3"
}
] | 2021-02-10 | [
[
"Shaw",
"Avirup",
""
]
] | We measure the impact of nonvanishing boundary localised terms on $\Delta B=2$ transitions in five-dimensional Universal Extra Dimensional scenario where masses and coupling strengths of several interactions of Kaluza-Klein modes are significantly modified with respect to the minimal counterpart. In such scenario we estimate the Kaluza-Klein contributions of quarks, gauge bosons and charged Higgs by evaluating the one-loop box diagrams that are responsible for the $\Delta B=2$ transitions. Using the loop function (obtained from one-loop box diagrams) we determine several important elements that are involved in Wolfenstein parametrisation. Moreover, with these elements we also study the geometrical shape of unitarity triangle. Besides, we compute the quantity $\Delta M_s$ scaled by the corresponding Standard Model value. Outcomes of our theoretical predictions have been compared to the allowed ranges of the corresponding observables simultaneously. Our current analysis shows that, depending on the parameters in this scenario the lower limit on the inverse of the radius of compactification can reach to an appreciable large value ($\approx 1.48$ TeV or even higher). |
hep-ph/9912265 | Martin Schmaltz | Eugene A. Mirabelli and Martin Schmaltz | Yukawa Hierarchies from Split Fermions in Extra Dimensions | 18 pages, references added | Phys.Rev. D61 (2000) 113011 | 10.1103/PhysRevD.61.113011 | SLAC-PUB-8309 | hep-ph | null | We explore a mechanism for generating the Yukawa hierarchies by displacing
the left- and right-handed components of the Standard Model fermions in a
higher-dimensional space. We find a unique configuration of displacements which
fits all quark and lepton masses and mixing angles, with a prediction for the
strange quark mass m_s = 120 MeV.
| [
{
"created": "Tue, 7 Dec 1999 23:19:59 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Dec 1999 03:09:44 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Mirabelli",
"Eugene A.",
""
],
[
"Schmaltz",
"Martin",
""
]
] | We explore a mechanism for generating the Yukawa hierarchies by displacing the left- and right-handed components of the Standard Model fermions in a higher-dimensional space. We find a unique configuration of displacements which fits all quark and lepton masses and mixing angles, with a prediction for the strange quark mass m_s = 120 MeV. |
hep-ph/9710314 | Qaisar Shafi | G. Dvali (CERN), G. Lazarides (CERN, Aristotle Univ.) and Q. Shafi
(Bartol Res. Inst.) | Mu Problem and Hybrid Inflation in Supersymmetric SU(2)_L x SU(2)_R x
U(1)_B-L | 11 pages, LaTeX, RevTeX, no figs | Phys.Lett.B424:259-264,1998 | 10.1016/S0370-2693(98)00145-2 | BA-97-25, CERN-TH/97-275 | hep-ph | null | We present a solution of the mu problem within a supersymmetric model based
on the SU(2)_L x SU(2)_R x U(1)_{B-L} gauge group. We show that this solution
implies a built-in hybrid inflationary scenario, which may result in a
successful baryogenesis via leptogenesis. Baryon number is essentially
conserved as a result of an R-symmetry. Neutrinos with mass in the eV range can
provide the `hot' dark matter component.
| [
{
"created": "Fri, 10 Oct 1997 18:45:53 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Dvali",
"G.",
"",
"CERN"
],
[
"Lazarides",
"G.",
"",
"CERN, Aristotle Univ."
],
[
"Shafi",
"Q.",
"",
"Bartol Res. Inst."
]
] | We present a solution of the mu problem within a supersymmetric model based on the SU(2)_L x SU(2)_R x U(1)_{B-L} gauge group. We show that this solution implies a built-in hybrid inflationary scenario, which may result in a successful baryogenesis via leptogenesis. Baryon number is essentially conserved as a result of an R-symmetry. Neutrinos with mass in the eV range can provide the `hot' dark matter component. |
hep-ph/0605024 | Gero von Gersdorff | D. Diego, G. von Gersdorff and M. Quiros | The MSSM from Scherk-Schwarz Supersymmetry Breaking | 23 pages, 3 figures | Phys.Rev. D74 (2006) 055004 | 10.1103/PhysRevD.74.055004 | null | hep-ph | null | We present a five-dimensional model compactified on an interval where
supersymmetry is broken by the Scherk-Schwarz mechanism. The gauge sector
propagates in the bulk, two Higgs hypermultiplets are quasilocalized, and quark
and lepton multiplets localized, in one of the boundaries. The effective
four-dimensional theory is the MSSM with very heavy gauginos, heavy squarks and
light sleptons and Higgsinos. The soft tree-level squared masses of the Higgs
sector can be negative and they can (partially) cancel the positive one-loop
contributions from the gauge sector. Electroweak symmetry breaking can then
comfortably be triggered by two-loop radiative corrections from the top-stop
sector. The fine tuning required to obtain the electroweak scale is found to be
much smaller than in the MSSM, with essentially no fine-tuning for few TeV
gaugino masses. All bounds from direct Higgs searches at LEP and from
electroweak precision observables can be satisfied. The lightest supersymmetric
particle is a (Higgsino-like) neutralino that can accomodate the abundance of
Dark Matter consistently with recent WMAP observations.
| [
{
"created": "Mon, 1 May 2006 19:27:30 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Diego",
"D.",
""
],
[
"von Gersdorff",
"G.",
""
],
[
"Quiros",
"M.",
""
]
] | We present a five-dimensional model compactified on an interval where supersymmetry is broken by the Scherk-Schwarz mechanism. The gauge sector propagates in the bulk, two Higgs hypermultiplets are quasilocalized, and quark and lepton multiplets localized, in one of the boundaries. The effective four-dimensional theory is the MSSM with very heavy gauginos, heavy squarks and light sleptons and Higgsinos. The soft tree-level squared masses of the Higgs sector can be negative and they can (partially) cancel the positive one-loop contributions from the gauge sector. Electroweak symmetry breaking can then comfortably be triggered by two-loop radiative corrections from the top-stop sector. The fine tuning required to obtain the electroweak scale is found to be much smaller than in the MSSM, with essentially no fine-tuning for few TeV gaugino masses. All bounds from direct Higgs searches at LEP and from electroweak precision observables can be satisfied. The lightest supersymmetric particle is a (Higgsino-like) neutralino that can accomodate the abundance of Dark Matter consistently with recent WMAP observations. |
2312.13079 | Sameer Ahmad Mir | Sameer Ahmad Mir, Nasir Ahmad Rather, Iqbal Mohi Ud Din and Saeed
Uddin | Hadron Production in Ultra-relativistic Nuclear Collisions and Finite
Baryon-Size Effects | 10 pages, 13 figures | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate relative hadron yield production of various like and unlike
mass particles in ultra-relativistic heavy ion collisions by employing a
statistical thermal model with finite-sized baryons (antibaryons) to imitate
the hard-core repulsive interactions leading to the excluded volume type
effect. A strong evidence of strangeness suppression relative to the
non-strange ones, mainly pions, particularly at higher energies is also
observed. This study also indicates that at chemical freeze-out the particle
ratios and strangeness suppression in the system obtained theoretically are
sensitive to baryonic (antibaryonic) hard-core radius ($r_B$). A comparison
with earlier analysis involving the strangeness suppression effect is made
where baryons and antibaryons were treated as point-like particles. The
available experimental data showing energy dependence of various particle
ratios are well described throughout the range of centre-of-mass energy
($\sqrt{s_{NN}}$). The value of hard-core radius between 0.76 to 0.79 fm is
found to fit the data quite well using $\chi^{2}$ minimization technique. Two
different chemical freeze-out stages are found where the earlier one belongs to
baryonic (hyperonic), antibaryonic (antihyperonic) states and the later one to
mesonic degrees of freedom.
| [
{
"created": "Wed, 20 Dec 2023 15:00:12 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Mar 2024 03:14:14 GMT",
"version": "v2"
},
{
"created": "Sun, 4 Aug 2024 17:44:56 GMT",
"version": "v3"
}
] | 2024-08-06 | [
[
"Mir",
"Sameer Ahmad",
""
],
[
"Rather",
"Nasir Ahmad",
""
],
[
"Din",
"Iqbal Mohi Ud",
""
],
[
"Uddin",
"Saeed",
""
]
] | We investigate relative hadron yield production of various like and unlike mass particles in ultra-relativistic heavy ion collisions by employing a statistical thermal model with finite-sized baryons (antibaryons) to imitate the hard-core repulsive interactions leading to the excluded volume type effect. A strong evidence of strangeness suppression relative to the non-strange ones, mainly pions, particularly at higher energies is also observed. This study also indicates that at chemical freeze-out the particle ratios and strangeness suppression in the system obtained theoretically are sensitive to baryonic (antibaryonic) hard-core radius ($r_B$). A comparison with earlier analysis involving the strangeness suppression effect is made where baryons and antibaryons were treated as point-like particles. The available experimental data showing energy dependence of various particle ratios are well described throughout the range of centre-of-mass energy ($\sqrt{s_{NN}}$). The value of hard-core radius between 0.76 to 0.79 fm is found to fit the data quite well using $\chi^{2}$ minimization technique. Two different chemical freeze-out stages are found where the earlier one belongs to baryonic (hyperonic), antibaryonic (antihyperonic) states and the later one to mesonic degrees of freedom. |
1705.05314 | Margarete Muhlleitner | R. Grober, M. Muhlleitner, M. Spira | Higgs Pair Production at NLO QCD for CP-violating Higgs Sectors | null | null | 10.1016/j.nuclphysb.2017.10.002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Higgs pair production through gluon fusion is an important process at the LHC
to test the dynamics underlying electroweak symmetry breaking. Higgs sectors
beyond the Standard Model (SM) can substantially modify this cross section
through novel couplings not present in the SM or the on-shell production of new
heavy Higgs bosons that subsequently decay into Higgs pairs. CP violation in
the Higgs sector is important for the explanation of the observed
matter-antimatter asymmetry through electroweak baryogenesis. In this work we
compute the next-to-leading order (NLO) QCD corrections in the heavy top quark
limit, including the effects of CP violation in the Higgs sector. We choose the
effective theory (EFT) approach, which provides a rather model-independent way
to explore New Physics (NP) effects by adding dimension-6 operators, both
CP-conserving and CP-violating ones, to the SM Lagrangian. Furthermore, we
perform the computation within a specific UV-complete model and choose as
benchmark model the general 2-Higgs-Doublet Model with CP violation, the C2HDM.
Depending on the dimension-6 coefficients, the relative NLO QCD corrections are
affected by several per cent through the new CP-violating operators. This is
also the case for SM-like Higgs pair production in the C2HDM, while the
relative QCD corrections in the production of heavier C2HDM Higgs boson pairs
deviate more strongly from the SM case. The absolute cross sections both in the
EFT and the C2HDM can be modified by more than an order of magnitude. In
particular, in the C2HDM the resonant production of Higgs pairs can by far
exceed the SM cross section.
| [
{
"created": "Mon, 15 May 2017 16:13:49 GMT",
"version": "v1"
}
] | 2018-03-14 | [
[
"Grober",
"R.",
""
],
[
"Muhlleitner",
"M.",
""
],
[
"Spira",
"M.",
""
]
] | Higgs pair production through gluon fusion is an important process at the LHC to test the dynamics underlying electroweak symmetry breaking. Higgs sectors beyond the Standard Model (SM) can substantially modify this cross section through novel couplings not present in the SM or the on-shell production of new heavy Higgs bosons that subsequently decay into Higgs pairs. CP violation in the Higgs sector is important for the explanation of the observed matter-antimatter asymmetry through electroweak baryogenesis. In this work we compute the next-to-leading order (NLO) QCD corrections in the heavy top quark limit, including the effects of CP violation in the Higgs sector. We choose the effective theory (EFT) approach, which provides a rather model-independent way to explore New Physics (NP) effects by adding dimension-6 operators, both CP-conserving and CP-violating ones, to the SM Lagrangian. Furthermore, we perform the computation within a specific UV-complete model and choose as benchmark model the general 2-Higgs-Doublet Model with CP violation, the C2HDM. Depending on the dimension-6 coefficients, the relative NLO QCD corrections are affected by several per cent through the new CP-violating operators. This is also the case for SM-like Higgs pair production in the C2HDM, while the relative QCD corrections in the production of heavier C2HDM Higgs boson pairs deviate more strongly from the SM case. The absolute cross sections both in the EFT and the C2HDM can be modified by more than an order of magnitude. In particular, in the C2HDM the resonant production of Higgs pairs can by far exceed the SM cross section. |
0909.0949 | Pierre Sikivie | P. Sikivie | Dark matter axions | 12 pages, invited talk at the Workshop `Crossing the Boundaries:
Gauge Dynamics at Strong Coupling' in honor of Misha Shifman's 60th birthday,
March 14-17, 2009, in Minneapolis, MN | null | 10.1142/S0217751X10048846 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The hypothesis of an `invisible' axion was made by Misha Shifman and others,
approximately thirty years ago. It has turned out to be an unusually fruitful
idea, crossing boundaries between particle physics, astrophysics and cosmology.
An axion with mass of order $10^{-5}$ eV (with large uncertainties) is one of
the leading candidates for the dark matter of the universe. It was found
recently that dark matter axions thermalize and form a Bose-Einstein condensate
(BEC). Because they form a BEC, axions differ from ordinary cold dark matter
(CDM) in the non-linear regime of structure formation and upon entering the
horizon. Axion BEC provides a mechanism for the production of net overall
rotation in dark matter halos, and for the alignment of cosmic microwave
anisotropy multipoles. Because there is evidence for these phenomena,
unexplained with ordinary CDM, an argument can be made that the dark matter is
axions.
| [
{
"created": "Fri, 4 Sep 2009 20:03:28 GMT",
"version": "v1"
}
] | 2015-05-14 | [
[
"Sikivie",
"P.",
""
]
] | The hypothesis of an `invisible' axion was made by Misha Shifman and others, approximately thirty years ago. It has turned out to be an unusually fruitful idea, crossing boundaries between particle physics, astrophysics and cosmology. An axion with mass of order $10^{-5}$ eV (with large uncertainties) is one of the leading candidates for the dark matter of the universe. It was found recently that dark matter axions thermalize and form a Bose-Einstein condensate (BEC). Because they form a BEC, axions differ from ordinary cold dark matter (CDM) in the non-linear regime of structure formation and upon entering the horizon. Axion BEC provides a mechanism for the production of net overall rotation in dark matter halos, and for the alignment of cosmic microwave anisotropy multipoles. Because there is evidence for these phenomena, unexplained with ordinary CDM, an argument can be made that the dark matter is axions. |
hep-ph/0410035 | Daniel T. Larson | Daniel T. Larson | Proton Decay and the Planck Scale | 6 pages, 3 figures, talk given at PASCOS '04, to appear in the
proceedings | null | 10.1142/9789812701756_0051 | null | hep-ph | null | Even without grand unification, proton decay can be a powerful probe of
physics at the highest energy scales. Supersymmetric theories with conserved
R-parity contain Planck-suppressed dimension 5 operators that give important
contributions to nucleon decay. These operators are likely controlled by flavor
physics, which means current and near future proton decay experiments might
yield clues about the fermion mass spectrum. I present a thorough analysis of
nucleon partial lifetimes in supersymmetric one-flavon Froggatt-Nielsen models
with a single U(1)_X family symmetry which is responsible for the fermionic
mass spectrum as well as forbidding R-parity violating interactions. Many of
the models naturally lead to nucleon decay near present limits without any
reference to grand unification.
| [
{
"created": "Sat, 2 Oct 2004 22:20:55 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Larson",
"Daniel T.",
""
]
] | Even without grand unification, proton decay can be a powerful probe of physics at the highest energy scales. Supersymmetric theories with conserved R-parity contain Planck-suppressed dimension 5 operators that give important contributions to nucleon decay. These operators are likely controlled by flavor physics, which means current and near future proton decay experiments might yield clues about the fermion mass spectrum. I present a thorough analysis of nucleon partial lifetimes in supersymmetric one-flavon Froggatt-Nielsen models with a single U(1)_X family symmetry which is responsible for the fermionic mass spectrum as well as forbidding R-parity violating interactions. Many of the models naturally lead to nucleon decay near present limits without any reference to grand unification. |
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