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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1310.6240 | Daniel Pitonyak | D. Pitonyak, M. Schlegel, A. Metz | Polarized hadron pair production from electron-positron annihilation | 29 pages, 5 figures, Version to appear in Phys. Rev. D | null | 10.1103/PhysRevD.89.054032 | RBRC-1046 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the production of two almost back-to-back hadrons from the
annihilation of an electron and a positron, allowing for the polarization of
all particles involved. In particular, we conduct a general (model-independent)
structure function decomposition of the cross section for the case $e^+e^- \to
\gamma^* \to h_ah_bX$. Moreover, using the parton model we calculate the
relevant structure functions in terms of twist-2 transverse momentum dependent
(TMD) fragmentation functions (FFs). We also give results for the situation
$e^+e^- \to Z^* \to h_ah_bX$ (including $\gamma$-$Z$ interference) within this
model. This is the first time a complete framework has been presented for the
examination of TMD FFs within $e^+e^-\to h_ah_bX$. We also specify certain
parts of our analysis that hold for the triple-polarized semi-inclusive
deep-inelastic scattering process and for di-hadron fragmentation. Furthermore,
we give an explicit prescription of how our work can be translated to the
Drell-Yan reaction, which provides for the first time full results for
double-polarized Drell-Yan that include electroweak effects. We further discuss
the relevance of our $e^+e^-\to h_ah_bX$ results for future experiments at
$e^+e^-$ machines.
| [
{
"created": "Wed, 23 Oct 2013 14:34:18 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Mar 2014 15:28:12 GMT",
"version": "v2"
}
] | 2015-06-17 | [
[
"Pitonyak",
"D.",
""
],
[
"Schlegel",
"M.",
""
],
[
"Metz",
"A.",
""
]
] | We study the production of two almost back-to-back hadrons from the annihilation of an electron and a positron, allowing for the polarization of all particles involved. In particular, we conduct a general (model-independent) structure function decomposition of the cross section for the case $e^+e^- \to \gamma^* \to h_ah_bX$. Moreover, using the parton model we calculate the relevant structure functions in terms of twist-2 transverse momentum dependent (TMD) fragmentation functions (FFs). We also give results for the situation $e^+e^- \to Z^* \to h_ah_bX$ (including $\gamma$-$Z$ interference) within this model. This is the first time a complete framework has been presented for the examination of TMD FFs within $e^+e^-\to h_ah_bX$. We also specify certain parts of our analysis that hold for the triple-polarized semi-inclusive deep-inelastic scattering process and for di-hadron fragmentation. Furthermore, we give an explicit prescription of how our work can be translated to the Drell-Yan reaction, which provides for the first time full results for double-polarized Drell-Yan that include electroweak effects. We further discuss the relevance of our $e^+e^-\to h_ah_bX$ results for future experiments at $e^+e^-$ machines. |
0901.2560 | Michael Lublinsky | Tolga Altinoluk, Alex Kovner, Michael Lublinsky | Inclusive Gluon Production in the QCD Reggeon Field Theory: Pomeron
Loops Included | 26 pages | JHEP 0903:110,2009 | 10.1088/1126-6708/2009/03/110 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We continue the study of hadronic scattering amplitudes at high energy by
systematically including nonlinear effects of finite partonic density in
hadronic wave function as well as the effects of multiple rescatterings in the
scattering process. In this paper we derive expressions for a single inclusive
gluon production amplitude and multigluon inclusive production amplitudes when
the rapidities of all observed gluons are not very different. We show that at
leading order these observables exhibit a semiclassical structure. Beyond the
semiclassical result, we find that the gluon emission has some characteristic
features different from the JIMWLK and KLWMIJ limits in that the gluons are not
emitted independently in rapidity space, but have a correlated component with
correlation length (in rapidity space) of order one. We demonstrate the
consistency between this feature of the multigluon observables and the
Hamiltonian of the QCD Reggeon Field Theory ($H_{RFT}$) derived in the
companion paper \cite{rft}. We also show that the evolution of these
observables with total rapidity of the process is generated by $H_{RFT}$ of
\cite{rft}. We discuss whether this evolution is equivalent to evolution with
$H_{JIMWLK}$ as far as this set of observables is concerned.
| [
{
"created": "Fri, 16 Jan 2009 20:23:09 GMT",
"version": "v1"
}
] | 2009-04-02 | [
[
"Altinoluk",
"Tolga",
""
],
[
"Kovner",
"Alex",
""
],
[
"Lublinsky",
"Michael",
""
]
] | We continue the study of hadronic scattering amplitudes at high energy by systematically including nonlinear effects of finite partonic density in hadronic wave function as well as the effects of multiple rescatterings in the scattering process. In this paper we derive expressions for a single inclusive gluon production amplitude and multigluon inclusive production amplitudes when the rapidities of all observed gluons are not very different. We show that at leading order these observables exhibit a semiclassical structure. Beyond the semiclassical result, we find that the gluon emission has some characteristic features different from the JIMWLK and KLWMIJ limits in that the gluons are not emitted independently in rapidity space, but have a correlated component with correlation length (in rapidity space) of order one. We demonstrate the consistency between this feature of the multigluon observables and the Hamiltonian of the QCD Reggeon Field Theory ($H_{RFT}$) derived in the companion paper \cite{rft}. We also show that the evolution of these observables with total rapidity of the process is generated by $H_{RFT}$ of \cite{rft}. We discuss whether this evolution is equivalent to evolution with $H_{JIMWLK}$ as far as this set of observables is concerned. |
2204.05024 | Hyun Min Lee | Hyun Min Lee, Kimiko Yamashita | A Model of Vector-like Leptons for the Muon $g-2$ and the $W$ Boson Mass | 18 pages, 4 figures, v2: references and discussion on dilepton bounds
added, v3: version to be published in Eur. Phys. J. C | null | 10.1140/epjc/s10052-022-10635-z | null | hep-ph | http://creativecommons.org/licenses/by-nc-nd/4.0/ | We consider a simple extension of the Standard Model (SM) with a vector-like
lepton and a local $U(1)'$ symmetry, motivated by the recent experimental
anomalies in the muon $g-2$ and the $W$ boson mass. The $U(1)'$ symmetry is
spontaneously broken by the VEVs of the dark Higgs scalar and the second Higgs
doublet, giving rise to the mixing between the muon and the vector-like lepton.
As a result, we obtain the desirable corrections to the muon $g-2$ and the $W$
boson mass simultaneously, dominantly due to the $Z'$ gauge interactions for
the vector-like lepton and the second Higgs doublet, respectively. We also
discuss the consistency of the model with the $Z$ boson decay width, the Higgs
couplings and the dilepton bounds.
| [
{
"created": "Mon, 11 Apr 2022 11:43:03 GMT",
"version": "v1"
},
{
"created": "Sun, 17 Apr 2022 14:36:56 GMT",
"version": "v2"
},
{
"created": "Sat, 23 Jul 2022 22:17:17 GMT",
"version": "v3"
}
] | 2022-08-24 | [
[
"Lee",
"Hyun Min",
""
],
[
"Yamashita",
"Kimiko",
""
]
] | We consider a simple extension of the Standard Model (SM) with a vector-like lepton and a local $U(1)'$ symmetry, motivated by the recent experimental anomalies in the muon $g-2$ and the $W$ boson mass. The $U(1)'$ symmetry is spontaneously broken by the VEVs of the dark Higgs scalar and the second Higgs doublet, giving rise to the mixing between the muon and the vector-like lepton. As a result, we obtain the desirable corrections to the muon $g-2$ and the $W$ boson mass simultaneously, dominantly due to the $Z'$ gauge interactions for the vector-like lepton and the second Higgs doublet, respectively. We also discuss the consistency of the model with the $Z$ boson decay width, the Higgs couplings and the dilepton bounds. |
hep-ph/0012291 | Antti Sorri | Kari Enqvist, Kimmo Kainulainen and Antti Sorri | Creation of large spatial fluctuations in neutrino asymmetry by neutrino
oscillations | 1+21 pages, 3 figures | JHEP 0104 (2001) 012 | 10.1088/1126-6708/2001/04/012 | HIP-2000-54/TH, NORDITA 2000/92 HE | hep-ph astro-ph | null | We consider active-sterile neutrino oscillations in the early universe in an
inhomogeneous isocurvature background. We show that very small initial baryonic
seed-inhomogeneities can trigger a growth of very large amplitude spatial
fluctuations in lepton asymmetry. Domains of varying asymmetry are observed to
persist for a long time despite dissipative effects. The space dependent
asymmetry profiles give rise to MSW-resonances within the domain boundaries,
enhancing dramatically the equilibration of the sterile neutrino species.
According to our one-dimensional toy-model, the effect is so strong that almost
the entire parameter space where exponential growth of asymmetry occurs would
be ruled out by nucleosynthesis.
| [
{
"created": "Thu, 21 Dec 2000 15:41:04 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Enqvist",
"Kari",
""
],
[
"Kainulainen",
"Kimmo",
""
],
[
"Sorri",
"Antti",
""
]
] | We consider active-sterile neutrino oscillations in the early universe in an inhomogeneous isocurvature background. We show that very small initial baryonic seed-inhomogeneities can trigger a growth of very large amplitude spatial fluctuations in lepton asymmetry. Domains of varying asymmetry are observed to persist for a long time despite dissipative effects. The space dependent asymmetry profiles give rise to MSW-resonances within the domain boundaries, enhancing dramatically the equilibration of the sterile neutrino species. According to our one-dimensional toy-model, the effect is so strong that almost the entire parameter space where exponential growth of asymmetry occurs would be ruled out by nucleosynthesis. |
1607.01933 | Antonio Costantini | Priyotosh Bandyopadhyay, Claudio Coriano, Antonio Costantini, Luigi
Delle Rose | Bounds on the Conformal Scale of a Minimally Coupled Dilaton and
Multi-Leptonic Signatures at the LHC | 26 pages, 37 figures and 7 tables, corrected final version to appear
on JHEP | null | 10.1007/JHEP09(2016)084 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore the potential for the discovery of a dilaton
$\mathcal{O}(200-500)$ GeV in a classical scale/conformal invariant extension
of the Standard Model by investigating the size of the corresponding breaking
scale $\Lambda$ at the LHC, extending a previous analysis. In particular, we
address the recent bounds on $\Lambda$ derived from Higgs boson searches. We
investigate if such a dilaton can be produced via gluon-gluon fusion,
presenting rates for its decay either into a pair of Higgs bosons or into two
heavy gauge bosons, which can give rise to multi-leptonic final states. A
detailed analysis via PYTHIA-FastJet has been carried out of the dominant
Standard Model backgrounds, at a centre of mass energy of 14 TeV. We show that
early data of $\sim 20$ fb$^{-1}$ can certainly probe the region of parameter
space where such a dilaton is allowed. A conformal scale of 5 TeV is allowed by
the current data, for almost all values of the dilaton mass investigated.
| [
{
"created": "Thu, 7 Jul 2016 09:30:34 GMT",
"version": "v1"
},
{
"created": "Tue, 12 Jul 2016 17:47:47 GMT",
"version": "v2"
},
{
"created": "Sun, 17 Jul 2016 07:20:26 GMT",
"version": "v3"
},
{
"created": "Tue, 13 Sep 2016 08:25:31 GMT",
"version": "v4"
}
] | 2016-10-12 | [
[
"Bandyopadhyay",
"Priyotosh",
""
],
[
"Coriano",
"Claudio",
""
],
[
"Costantini",
"Antonio",
""
],
[
"Rose",
"Luigi Delle",
""
]
] | We explore the potential for the discovery of a dilaton $\mathcal{O}(200-500)$ GeV in a classical scale/conformal invariant extension of the Standard Model by investigating the size of the corresponding breaking scale $\Lambda$ at the LHC, extending a previous analysis. In particular, we address the recent bounds on $\Lambda$ derived from Higgs boson searches. We investigate if such a dilaton can be produced via gluon-gluon fusion, presenting rates for its decay either into a pair of Higgs bosons or into two heavy gauge bosons, which can give rise to multi-leptonic final states. A detailed analysis via PYTHIA-FastJet has been carried out of the dominant Standard Model backgrounds, at a centre of mass energy of 14 TeV. We show that early data of $\sim 20$ fb$^{-1}$ can certainly probe the region of parameter space where such a dilaton is allowed. A conformal scale of 5 TeV is allowed by the current data, for almost all values of the dilaton mass investigated. |
1905.11179 | Antonio Dobado | Adri\'an Casado-Turri\'on and Antonio Dobado | Triggering the QCD phase transition through the Unruh effect: chiral
symmetry restoration for uniformly accelerated observers | null | Phys. Rev. D 99, 125018 (2019) | 10.1103/PhysRevD.99.125018 | null | hep-ph gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we study the chiral phase transition as observed by an
accelerating observer taking into account the Unruh effect. We use Chiral
Perturbation Theory at leading order and the large $N$ limit ($N$ being the
number of pions) as an effective description of low-energy QCD, and the
Thermalization Theorem to compute the relevant partition function for the
accelerating observer. As a result, we obtain that chiral symmetry is restored
for uniformly accelerated observers with acceleration $a$ larger than the
critical value $a_c=4\pi f_\pi$, with $f_\pi$ being the pion decay constant.
| [
{
"created": "Mon, 27 May 2019 12:56:41 GMT",
"version": "v1"
}
] | 2019-07-03 | [
[
"Casado-Turrión",
"Adrián",
""
],
[
"Dobado",
"Antonio",
""
]
] | In this work we study the chiral phase transition as observed by an accelerating observer taking into account the Unruh effect. We use Chiral Perturbation Theory at leading order and the large $N$ limit ($N$ being the number of pions) as an effective description of low-energy QCD, and the Thermalization Theorem to compute the relevant partition function for the accelerating observer. As a result, we obtain that chiral symmetry is restored for uniformly accelerated observers with acceleration $a$ larger than the critical value $a_c=4\pi f_\pi$, with $f_\pi$ being the pion decay constant. |
hep-ph/9808284 | null | R. N. Mohapatra | Particle Physics Implications of Neutrinoless Double Beta Decay | 10 pages; four figures: Invited talk presented at the NEUTRINO 98
conference held in Takayama, Japan, June, 1998; to appear in the proceedings;
references added | Nucl.Phys.Proc.Suppl. 77 (1999) 376-385 | 10.1016/S0920-5632(99)00447-8 | null | hep-ph | null | Neutrinoless double beta decay is a sensitive probe of the patterns of
neutrino masses and mixings if the neutrinos are Majorana particles as well as
other new physics scenarios beyond the standard model. In this talk, the
present experimental lower bound on the lifetime for $\beta\beta_{0\nu}$ is
used to constrain the neutrino mixings and set limits on the parameters of the
new physics scenarios such as the left-right symmetric models, R-parity
violating SUSY models etc which lead to this process. We also discuss proposed
high precision searches for $\beta\beta_{0\nu}$ decay that can provide
extremely valuable insight not only into the nature of neutrino mixings and
masses but also put constraints on (or even rule out) new physics scenarios.
| [
{
"created": "Mon, 10 Aug 1998 18:06:24 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Aug 1998 17:19:00 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Mohapatra",
"R. N.",
""
]
] | Neutrinoless double beta decay is a sensitive probe of the patterns of neutrino masses and mixings if the neutrinos are Majorana particles as well as other new physics scenarios beyond the standard model. In this talk, the present experimental lower bound on the lifetime for $\beta\beta_{0\nu}$ is used to constrain the neutrino mixings and set limits on the parameters of the new physics scenarios such as the left-right symmetric models, R-parity violating SUSY models etc which lead to this process. We also discuss proposed high precision searches for $\beta\beta_{0\nu}$ decay that can provide extremely valuable insight not only into the nature of neutrino mixings and masses but also put constraints on (or even rule out) new physics scenarios. |
1005.5382 | Juan Antonio Aguilar-Saavedra | J. A. Aguilar-Saavedra, J. Bernabeu | W polarisation beyond helicity fractions in top quark decays | LaTeX 36 pages, 51 EPS figures. Typos corrected. To appear in NPB | Nucl.Phys.B840:349-378,2010 | 10.1016/j.nuclphysb.2010.07.012 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the density matrix for the decay of a polarised top quark into a
polarised W boson and a massive b quark, for the most general Wtb vertex
arising from dimension-six gauge-invariant effective operators. We show that,
in addition to the well-known W helicity fractions, for polarised top decays it
is worth to define and study the transverse and normal W polarisation
fractions, that is, the W polarisation along two directions orthogonal to its
momentum. In particular, a rather simple forward-backward asymmetry in the
normal direction is found to be very sensitive to complex phases in one of the
Wtb anomalous couplings. This asymmetry, which indicates a normal W
polarisation, can be generated for example by a P-odd, T-odd transition
electric dipole moment. We also investigate the angular distribution of decay
products in the top quark rest frame, calculating the spin analysing powers for
a general Wtb vertex. Finally we show that, using a combined fit to top decay
observables and the tW cross section, at LHC it will be possible to obtain
model-independent measurements of all the (complex) Wtb couplings as well as
the single top polarisation. Implications for spin correlations in top pair
production are also discussed.
| [
{
"created": "Fri, 28 May 2010 20:00:02 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Aug 2010 13:22:51 GMT",
"version": "v2"
}
] | 2014-11-21 | [
[
"Aguilar-Saavedra",
"J. A.",
""
],
[
"Bernabeu",
"J.",
""
]
] | We calculate the density matrix for the decay of a polarised top quark into a polarised W boson and a massive b quark, for the most general Wtb vertex arising from dimension-six gauge-invariant effective operators. We show that, in addition to the well-known W helicity fractions, for polarised top decays it is worth to define and study the transverse and normal W polarisation fractions, that is, the W polarisation along two directions orthogonal to its momentum. In particular, a rather simple forward-backward asymmetry in the normal direction is found to be very sensitive to complex phases in one of the Wtb anomalous couplings. This asymmetry, which indicates a normal W polarisation, can be generated for example by a P-odd, T-odd transition electric dipole moment. We also investigate the angular distribution of decay products in the top quark rest frame, calculating the spin analysing powers for a general Wtb vertex. Finally we show that, using a combined fit to top decay observables and the tW cross section, at LHC it will be possible to obtain model-independent measurements of all the (complex) Wtb couplings as well as the single top polarisation. Implications for spin correlations in top pair production are also discussed. |
1202.2382 | Juan Antonio Aguilar-Saavedra | J. A. Aguilar-Saavedra | Overview of models for the t tbar asymmetry | LaTeX 6 pages. Proceedings of TOP2011, 4th International Workshop on
Top Quark Physics, 25-30th September 2011, Sant Feliu de Guixols, Spain | null | 10.1393/ncc/i2012-11240-7 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review the most popular models proposed to explain the anomalous
forward-backward asymmetry in t tbar production at the Tevatron. We discuss
their viability in view of recent LHC data. We summarise their predictions for
charge asymmetries at the LHC.
| [
{
"created": "Fri, 10 Feb 2012 23:03:07 GMT",
"version": "v1"
}
] | 2022-03-02 | [
[
"Aguilar-Saavedra",
"J. A.",
""
]
] | We review the most popular models proposed to explain the anomalous forward-backward asymmetry in t tbar production at the Tevatron. We discuss their viability in view of recent LHC data. We summarise their predictions for charge asymmetries at the LHC. |
hep-ph/0212248 | Roland Kirschner | R. Kirschner | Parton interactions in the Bjorken aymptotics | 19 pages LaTex, 3 eps-figures, reference added | null | null | NTZ 09/2002 | hep-ph | null | We demonstrate the effective action scheme for the leading parton
interactions and discuss the symmetry properties. The interaction kernels are
particular cases of conformal symmetric two-particle kernels. There is a direct
relation to the conformal symmetric rational solution of the Yang-Baxter
equation.
| [
{
"created": "Tue, 17 Dec 2002 12:14:35 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Jan 2003 08:47:31 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Kirschner",
"R.",
""
]
] | We demonstrate the effective action scheme for the leading parton interactions and discuss the symmetry properties. The interaction kernels are particular cases of conformal symmetric two-particle kernels. There is a direct relation to the conformal symmetric rational solution of the Yang-Baxter equation. |
1209.1051 | Paul Hohler | Paul M. Hohler and Ralf Rapp | Evaluating chiral symmetry restoration through the use of sum rules | 9 pages, conference proceedings from Resonance Workshop at UT Austin,
March 5-7 2012 | null | 10.1051/epjconf/20123600012 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We pursue the idea of assessing chiral restoration via in-medium
modifications of hadronic spectral functions of chiral partners. The usefulness
of sum rules in this endeavor is illustrated, focusing on the vector and
axial-vector channels. We first present an update on constructing quantitative
results for pertinent vacuum spectral functions. These spectral functions serve
as a basis upon which the in-medium spectral functions can be constructed. A
striking feature of our analysis of the vacuum spectral functions is the need
to include excited resonances, dictated by satisfying the Weinberg-type sum
rules. This includes excited states in both the vector and axial-vector
channels. Preliminary results for the finite temperature vector spectral
function are presented. Based on a rho spectral function tested in dilepton
data which develops a shoulder at low energies, we find that the rho' peak
flattens off. The flattening may be a sign of chiral restoration, though a
study of the finite temperature axial-vector spectral function remains to be
carried out.
| [
{
"created": "Wed, 5 Sep 2012 17:31:50 GMT",
"version": "v1"
}
] | 2015-06-11 | [
[
"Hohler",
"Paul M.",
""
],
[
"Rapp",
"Ralf",
""
]
] | We pursue the idea of assessing chiral restoration via in-medium modifications of hadronic spectral functions of chiral partners. The usefulness of sum rules in this endeavor is illustrated, focusing on the vector and axial-vector channels. We first present an update on constructing quantitative results for pertinent vacuum spectral functions. These spectral functions serve as a basis upon which the in-medium spectral functions can be constructed. A striking feature of our analysis of the vacuum spectral functions is the need to include excited resonances, dictated by satisfying the Weinberg-type sum rules. This includes excited states in both the vector and axial-vector channels. Preliminary results for the finite temperature vector spectral function are presented. Based on a rho spectral function tested in dilepton data which develops a shoulder at low energies, we find that the rho' peak flattens off. The flattening may be a sign of chiral restoration, though a study of the finite temperature axial-vector spectral function remains to be carried out. |
hep-ph/0611207 | Jonathan Rosner | Jonathan L. Rosner | Mass splittings in $\Sigma_b$ and $\Sigma_b^*$ | 6 pages, 1 figure, to be published in Phys. Rev. D (Brief Reports).
Numerical corrections; some text added | Phys.Rev.D75:013009,2007 | 10.1103/PhysRevD.75.013009 | EFI 06-23 | hep-ph hep-ex | null | The charged $\Sigma_b$ and $\Sigma^*_b$ states have recently been reported by
the CDF Collaboration. The relation of their reported charge-averaged masses to
expectations based on the quark model is reviewed briefly. A relation is proved
among the $\Delta I = 1$ electromagnetic mass differences $\Sigma_1 \equiv
M(\Sigma^+) - M(\Sigma^-)$, $\Sigma^*_1 \equiv M(\Sigma^{*+})- M(\Sigma^{*-})$,
$\Sigma_{b1} \equiv M(\Sigma_b^+) - M(\Sigma_b^-)$, and $\Sigma^*_{b1} \equiv
M(\Sigma_b^{*+}) - M(\Sigma_b^{*-})$. The relation is $\Sigma^*_{b1} -
\Sigma_{b1} = (m_s/m_b)(\Sigma^*_1 - \Sigma_1),$ leading to the expectation
$\Sigma^*_{b1} - \Sigma_{b1} = 0.40 \pm 0.07$ MeV.
| [
{
"created": "Wed, 15 Nov 2006 16:58:53 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Nov 2006 20:56:54 GMT",
"version": "v2"
},
{
"created": "Mon, 20 Nov 2006 21:26:50 GMT",
"version": "v3"
},
{
"created": "Sat, 6 Jan 2007 21:10:27 GMT",
"version": "v4"
}
] | 2008-11-26 | [
[
"Rosner",
"Jonathan L.",
""
]
] | The charged $\Sigma_b$ and $\Sigma^*_b$ states have recently been reported by the CDF Collaboration. The relation of their reported charge-averaged masses to expectations based on the quark model is reviewed briefly. A relation is proved among the $\Delta I = 1$ electromagnetic mass differences $\Sigma_1 \equiv M(\Sigma^+) - M(\Sigma^-)$, $\Sigma^*_1 \equiv M(\Sigma^{*+})- M(\Sigma^{*-})$, $\Sigma_{b1} \equiv M(\Sigma_b^+) - M(\Sigma_b^-)$, and $\Sigma^*_{b1} \equiv M(\Sigma_b^{*+}) - M(\Sigma_b^{*-})$. The relation is $\Sigma^*_{b1} - \Sigma_{b1} = (m_s/m_b)(\Sigma^*_1 - \Sigma_1),$ leading to the expectation $\Sigma^*_{b1} - \Sigma_{b1} = 0.40 \pm 0.07$ MeV. |
2106.10299 | Keping Xie | Keping Xie, T. J. Hobbs, Tie-Jiun Hou, Carl Schmidt, Mengshi Yan, and
C.-P. Yuan | The photon PDF within the CT18 global analysis | 45 pages, 27 figures, and 5 tables | null | 10.1103/PhysRevD.105.054006 | MSUHEP-21-013, PITT-PACC-2112, SMU-HEP-21-06,
FERMILAB-PUB-21-370-QIS-SCD-T | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Building upon the most recent CT18 global fit, we present a new calculation
of the photon content of the proton based on an application of the LUX
formalism. In this work, we explore two principal variations of the LUX ansatz.
In one approach, which we designate "CT18lux," the photon PDF is calculated
directly using the LUX formula for all scales, $\mu$. In an alternative
realization, "CT18qed," we instead initialize the photon PDF in terms of the
LUX formulation at a lower scale, $\mu\! \sim\! \mu_0$, and evolve to higher
scales with a combined QED+QCD kernel at
$\mathcal{O}(\alpha),~\mathcal{O}(\alpha\alpha_s)$ and $\mathcal{O}(\alpha^2)$.
While we find these two approaches generally agree, especially at intermediate
$x$ ($10^{-3}\lesssim x\lesssim0.3$), we discuss some moderate discrepancies
that can occur toward the end-point regions at very high or low $x$. We also
study effects that follow from variations of the inputs to the LUX calculation
originating outside the pure deeply-inelastic scattering (DIS) region,
including from elastic form factors and other contributions to the photon PDF.
Finally, we investigate the phenomenological implications of these photon PDFs
for the LHC, including high-mass Drell-Yan, vector-boson pair, top-quark pair,
and Higgs associated with vector-boson production.
| [
{
"created": "Fri, 18 Jun 2021 18:03:34 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Jul 2021 06:34:30 GMT",
"version": "v2"
},
{
"created": "Fri, 3 Sep 2021 02:13:50 GMT",
"version": "v3"
},
{
"created": "Sun, 12 Feb 2023 18:37:31 GMT",
"version": "v4"
}
] | 2023-02-14 | [
[
"Xie",
"Keping",
""
],
[
"Hobbs",
"T. J.",
""
],
[
"Hou",
"Tie-Jiun",
""
],
[
"Schmidt",
"Carl",
""
],
[
"Yan",
"Mengshi",
""
],
[
"Yuan",
"C. -P.",
""
]
] | Building upon the most recent CT18 global fit, we present a new calculation of the photon content of the proton based on an application of the LUX formalism. In this work, we explore two principal variations of the LUX ansatz. In one approach, which we designate "CT18lux," the photon PDF is calculated directly using the LUX formula for all scales, $\mu$. In an alternative realization, "CT18qed," we instead initialize the photon PDF in terms of the LUX formulation at a lower scale, $\mu\! \sim\! \mu_0$, and evolve to higher scales with a combined QED+QCD kernel at $\mathcal{O}(\alpha),~\mathcal{O}(\alpha\alpha_s)$ and $\mathcal{O}(\alpha^2)$. While we find these two approaches generally agree, especially at intermediate $x$ ($10^{-3}\lesssim x\lesssim0.3$), we discuss some moderate discrepancies that can occur toward the end-point regions at very high or low $x$. We also study effects that follow from variations of the inputs to the LUX calculation originating outside the pure deeply-inelastic scattering (DIS) region, including from elastic form factors and other contributions to the photon PDF. Finally, we investigate the phenomenological implications of these photon PDFs for the LHC, including high-mass Drell-Yan, vector-boson pair, top-quark pair, and Higgs associated with vector-boson production. |
hep-ph/0112073 | Ismd31 | Swagato Banerjee | Study of Rapidity Gap Events in Hadronic Z Decays with L3 detector | 4 pages, 7 figures (in eps) talk given at XXXI International
Symposium on Multiparticle Dynamics, Sep. 1-7, 2001, Datong China. see
http://ismd31.ccnu.edu.cn/ | null | 10.1142/9789812778048_0007 | null | hep-ph | null | Rapidity gaps have been studied in well separated completely symmetric 3 jet
events from hadronic Z decays to search for colour singlet exchange.
Asymmetries in particle flow and angular separation, defined with respect to
the inter-jet regions, are found to be sensitive to the exchange of a colour
singlet object instead of a colour octet gluon. %Comparing data from the L3
experiment with Monte Carlo predictions, %a limit is obtained on the fraction
%of colour singlet exchange in data. From a comparison of the distributions
observed in the L3 experiment and Monte Carlo predictions, a limit is obtained
on the fraction of colour singlet exchange in data.
| [
{
"created": "Wed, 5 Dec 2001 08:57:19 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Banerjee",
"Swagato",
""
]
] | Rapidity gaps have been studied in well separated completely symmetric 3 jet events from hadronic Z decays to search for colour singlet exchange. Asymmetries in particle flow and angular separation, defined with respect to the inter-jet regions, are found to be sensitive to the exchange of a colour singlet object instead of a colour octet gluon. %Comparing data from the L3 experiment with Monte Carlo predictions, %a limit is obtained on the fraction %of colour singlet exchange in data. From a comparison of the distributions observed in the L3 experiment and Monte Carlo predictions, a limit is obtained on the fraction of colour singlet exchange in data. |
2108.08897 | Fabrizio Caola | Fabrizio Caola, Silvia Ferrario Ravasio, Giovanni Limatola, Kirill
Melnikov and Paolo Nason | On linear power corrections in certain collider observables | v2: references added, minor typos corrected. Version published in
JHEP | null | 10.1007/JHEP01(2022)093 | OUTP-21-21P, TTP21-026, P3H-21-056 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study linear power corrections ${\cal O}(\Lambda_{\rm QCD}/Q)$ to certain
collider observables. We present arguments that prove that such corrections
cannot appear in observables that are inclusive with respect to QCD radiation,
such as total cross sections as well as rapidity and transverse momentum
distributions of color-neutral particles. Although our calculations are carried
out in a simplified framework, our arguments and conclusions are applicable,
with some reservations, to processes both at lepton and hadron colliders. We
also show how an improved understanding of the origin of linear power
corrections allows us to simplify their calculation. As an application, we
compute the leading non-perturbative corrections to the $C$-parameter and the
thrust in $e^+e^-$ annihilation in a generic three-jet configuration.
| [
{
"created": "Thu, 19 Aug 2021 20:23:08 GMT",
"version": "v1"
},
{
"created": "Sun, 12 Jun 2022 12:53:29 GMT",
"version": "v2"
}
] | 2022-06-14 | [
[
"Caola",
"Fabrizio",
""
],
[
"Ravasio",
"Silvia Ferrario",
""
],
[
"Limatola",
"Giovanni",
""
],
[
"Melnikov",
"Kirill",
""
],
[
"Nason",
"Paolo",
""
]
] | We study linear power corrections ${\cal O}(\Lambda_{\rm QCD}/Q)$ to certain collider observables. We present arguments that prove that such corrections cannot appear in observables that are inclusive with respect to QCD radiation, such as total cross sections as well as rapidity and transverse momentum distributions of color-neutral particles. Although our calculations are carried out in a simplified framework, our arguments and conclusions are applicable, with some reservations, to processes both at lepton and hadron colliders. We also show how an improved understanding of the origin of linear power corrections allows us to simplify their calculation. As an application, we compute the leading non-perturbative corrections to the $C$-parameter and the thrust in $e^+e^-$ annihilation in a generic three-jet configuration. |
hep-ph/9401288 | Qiping Xu | Patrick J. O'Donnell and Q. P. Xu | Semileptonic and Exclusive Rare B Decays | 13 pages, Latex, no figure, UTPT--94--02 | Phys.Lett. B325 (1994) 219-226 | 10.1016/0370-2693(94)90095-7 | null | hep-ph | null | The exclusive rare decay $B \ra K^\ast \gamma$ takes place in a region of
maximum recoil, $q^{2}=0$, posing a problem for nonrelativistic quark models
which are usually thought to be most reliable at zero recoil. The
Bauer--Stech--Wirbel (BSW) model, formulated in the infinite--momentum--frame
(IMF) formalism, is designed to work at $q^2=0$. We show in this model that the
ratio relating the decay $B \ra K^\ast \gamma$ and the $q^2$--spectrum of the
semileptonic decay $B\ra \rho e {\bar \nu}$, becomes independent of the wave
function in the SU(3) flavor symmetry limit. We show that this feature is also
true in relativistic quark models formulated in the IMF or light--cone
formalism, if the $b$ quark is infinitely heavy. In fact, these relativistic
models, which have a different spin structure from the BSW case, reduce to the
BSW model in the heavy $b$--quark limit. A direct measurement of the
$q^2$--spectrum of the semileptonic decay can therefore provide accurate
information for the exclusive rare decay.
| [
{
"created": "Wed, 19 Jan 1994 23:02:34 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"O'Donnell",
"Patrick J.",
""
],
[
"Xu",
"Q. P.",
""
]
] | The exclusive rare decay $B \ra K^\ast \gamma$ takes place in a region of maximum recoil, $q^{2}=0$, posing a problem for nonrelativistic quark models which are usually thought to be most reliable at zero recoil. The Bauer--Stech--Wirbel (BSW) model, formulated in the infinite--momentum--frame (IMF) formalism, is designed to work at $q^2=0$. We show in this model that the ratio relating the decay $B \ra K^\ast \gamma$ and the $q^2$--spectrum of the semileptonic decay $B\ra \rho e {\bar \nu}$, becomes independent of the wave function in the SU(3) flavor symmetry limit. We show that this feature is also true in relativistic quark models formulated in the IMF or light--cone formalism, if the $b$ quark is infinitely heavy. In fact, these relativistic models, which have a different spin structure from the BSW case, reduce to the BSW model in the heavy $b$--quark limit. A direct measurement of the $q^2$--spectrum of the semileptonic decay can therefore provide accurate information for the exclusive rare decay. |
hep-ph/0412091 | Shinji Maedan | Shinji Maedan | Space-time evolution of a condensate in the interaction representation | 18 pages,8 figures | null | null | TNCT-0401 | hep-ph | null | The space-time evolution of an inhomogeneous as well as homogeneous
condensate is studied. We use the $ \lambda \phi^4 $ model and adopt the
interaction representation in which the particle picture of the field $\phi$
with mass $m$ is definitely obtained. As the initial condition, a coherent
state is assumed. In the case of the homogeneous condensate, the amplitude of
it grows continuously with time and the perturbative calculation breaks down
for large time. On the other hand, in the case of the inhomogeneous condensate
with a finite initial size $\sim R$, the behavior of it is so different from
that of the homogeneous one. For $0< t < m R^2/2 $, the growth of the amplitude
of the inhomogeneous condensate at the origin $ ({\boldsymbol x}={\bf 0}) $ is
slowed down compared with that of the homogeneous one, and the contribution of
the interaction term $ (\lambda /4) :\phi^4: $ is restricted to the small
region around the origin of the condensate. For the late time, $ t > m R^2/2 $,
the condensate spreads into space.
| [
{
"created": "Tue, 7 Dec 2004 05:48:13 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Maedan",
"Shinji",
""
]
] | The space-time evolution of an inhomogeneous as well as homogeneous condensate is studied. We use the $ \lambda \phi^4 $ model and adopt the interaction representation in which the particle picture of the field $\phi$ with mass $m$ is definitely obtained. As the initial condition, a coherent state is assumed. In the case of the homogeneous condensate, the amplitude of it grows continuously with time and the perturbative calculation breaks down for large time. On the other hand, in the case of the inhomogeneous condensate with a finite initial size $\sim R$, the behavior of it is so different from that of the homogeneous one. For $0< t < m R^2/2 $, the growth of the amplitude of the inhomogeneous condensate at the origin $ ({\boldsymbol x}={\bf 0}) $ is slowed down compared with that of the homogeneous one, and the contribution of the interaction term $ (\lambda /4) :\phi^4: $ is restricted to the small region around the origin of the condensate. For the late time, $ t > m R^2/2 $, the condensate spreads into space. |
0809.1749 | Yuri Dokshitzer | Yu.L. Dokshitzer and G. Marchesini | Monte Carlo and large angle gluon radiation | accepted for publication by JHEP on 21.02.2009; to appear in March
2009 | JHEP 0903:117,2009 | 10.1088/1126-6708/2009/03/117 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the problem of incorporating recoil effects into the probabilistic
QCD evolution scheme based on the picture of colour dipoles as done in recent
Monte Carlo programs. Such a scheme correctly describes subleading soft
contributions to multiplicity distributions. However we find that a simple
receipt for incorporating recoil effects into the dipole multiplication picture
conflicts the collinear factorization and does not lead to the correct DGLAP
equation.
| [
{
"created": "Wed, 10 Sep 2008 09:58:13 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Mar 2009 15:14:20 GMT",
"version": "v2"
}
] | 2009-03-27 | [
[
"Dokshitzer",
"Yu. L.",
""
],
[
"Marchesini",
"G.",
""
]
] | We discuss the problem of incorporating recoil effects into the probabilistic QCD evolution scheme based on the picture of colour dipoles as done in recent Monte Carlo programs. Such a scheme correctly describes subleading soft contributions to multiplicity distributions. However we find that a simple receipt for incorporating recoil effects into the dipole multiplication picture conflicts the collinear factorization and does not lead to the correct DGLAP equation. |
1207.1849 | Krishna Kingkar Pathak | Krishna Kingkar Pathak, D. K. Choudhury and N. S. Bordoloi | Leptonic decay of Heavy-light Mesons in a QCD Potential Model | 9 pages,3 tables | Int. J. Mod. Phys.A Vol. 28 (2013) 1350010 | 10.1142/S0217751X13500103 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the masses and decay constants of heavy-light flavour mesons D, Ds,
B and Bs in a QCD Potential model. The mesonic wavefunction is used to compute
the masses of D and B mesons in the ground state and the wavefunction is
transformed to momentum space to estimate the pseudoscalar decay constants of
these mesons. The leptonic decay widths and branching ratio of these mesons for
different leptonic channels are also computed to compare with the experimental
values. The results are found to be compatible with available data.
| [
{
"created": "Sun, 8 Jul 2012 07:25:26 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Nov 2012 11:33:01 GMT",
"version": "v2"
},
{
"created": "Tue, 22 Jan 2013 07:29:07 GMT",
"version": "v3"
}
] | 2013-01-23 | [
[
"Pathak",
"Krishna Kingkar",
""
],
[
"Choudhury",
"D. K.",
""
],
[
"Bordoloi",
"N. S.",
""
]
] | We study the masses and decay constants of heavy-light flavour mesons D, Ds, B and Bs in a QCD Potential model. The mesonic wavefunction is used to compute the masses of D and B mesons in the ground state and the wavefunction is transformed to momentum space to estimate the pseudoscalar decay constants of these mesons. The leptonic decay widths and branching ratio of these mesons for different leptonic channels are also computed to compare with the experimental values. The results are found to be compatible with available data. |
2009.01828 | Ricardo Aguirre | R. M. Aguirre | Regularization of the Nambu-Jona Lasinio model under a uniform magnetic
field and the role of the anomalous magnetic moments | Major revision | null | 10.1103/PhysRevD.102.096025 | null | hep-ph astro-ph.HE nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The vacuum contribution to quark matter under a uniform magnetic field within
the SU(3) version of the Nambu and Jona-Lasinio model is studied. The standard
regularization procedure is examined and a new prescription is proposed. For
this purpose analytic regularization and a subtraction scheme are used to deal
with divergencies depending on the magnetic intensity. This scheme is combined
with the standard three momentum cutoff recipe, and reduces to it for vanishing
magnetic intensity. Furthermore, the effects of a direct coupling between the
anomalous magnetic moments of the quarks and the magnetic field is considered.
Single particle properties as well as bulk thermodynamical quantities are
studied for a configuration of matter found in neutron stars. A wide range of
baryonic densities and magnetic intensities are examined at zero temperature.
| [
{
"created": "Thu, 3 Sep 2020 17:49:38 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Nov 2020 12:28:36 GMT",
"version": "v2"
}
] | 2020-12-30 | [
[
"Aguirre",
"R. M.",
""
]
] | The vacuum contribution to quark matter under a uniform magnetic field within the SU(3) version of the Nambu and Jona-Lasinio model is studied. The standard regularization procedure is examined and a new prescription is proposed. For this purpose analytic regularization and a subtraction scheme are used to deal with divergencies depending on the magnetic intensity. This scheme is combined with the standard three momentum cutoff recipe, and reduces to it for vanishing magnetic intensity. Furthermore, the effects of a direct coupling between the anomalous magnetic moments of the quarks and the magnetic field is considered. Single particle properties as well as bulk thermodynamical quantities are studied for a configuration of matter found in neutron stars. A wide range of baryonic densities and magnetic intensities are examined at zero temperature. |
hep-ph/9807388 | Stephen Wong | S.M.H. Wong | Open Charm, Photon and Dilepton Production in an Increasingly Strongly
Interacting Parton Plasma | 10 pages, revtex style with 8 embedded PS figures, to appear in Phys.
Rev. C | Phys.Rev.C58:2358,1998 | 10.1103/PhysRevC.58.2358 | WU-B 97/32 | hep-ph nucl-th | null | We examine the effects of the new equilibration scenario of the increasingly
strongly interacting parton plasma and of the non-equilibrium environment have
on the production of open charm, photon and dilepton at LHC and at RHIC
energies. We show that an out-of-equilibrium effect, not shown before, changes
significantly the relative yield of the two main partonic contributions to
photon production in the higher $p_T$ range, and higher orders for
electromagnetic emissions have increased significance in the new scenario
especially at RHIC energies. We argue that the effects of the new scenario are
not restricted just to the parton phase but will continue through to the later
hadron gas phase with potentially positive implications for the detection of
the quark-gluon plasma.
| [
{
"created": "Wed, 15 Jul 1998 18:41:03 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Wong",
"S. M. H.",
""
]
] | We examine the effects of the new equilibration scenario of the increasingly strongly interacting parton plasma and of the non-equilibrium environment have on the production of open charm, photon and dilepton at LHC and at RHIC energies. We show that an out-of-equilibrium effect, not shown before, changes significantly the relative yield of the two main partonic contributions to photon production in the higher $p_T$ range, and higher orders for electromagnetic emissions have increased significance in the new scenario especially at RHIC energies. We argue that the effects of the new scenario are not restricted just to the parton phase but will continue through to the later hadron gas phase with potentially positive implications for the detection of the quark-gluon plasma. |
0902.0972 | Arunansu Sil | Philippe Brax, Carlos A. Savoy and Arunansu Sil | SQCD Inflation & SUSY Breaking | 15 pages, typos corrected, references added | JHEP 0904:092,2009 | 10.1088/1126-6708/2009/04/092 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A model of generalised hybrid inflation in a supersymmetric QCD theory is
proposed whose parameters are the gauge coupling and quark masses. Its
gravitational coupling to another SQCD sector induces a metastable
supersymmetry breaking vacuum of the ISS type as ISS quarks become massive at
the end of inflation. Using a known mechanism with a gravitational breaking of
the baryon number and the gauging of flavour symmetries, we find that gauge
mediation of supersymmetry breaking is compatible with the dynamics of the
inflation sector. Reheating proceeds via the thermalization of the ISS
messengers into the standard model states. This setup contains a single
dimensionful parameter in the form of a quark mass term in the inflationary
sector, i.e. all other scales involved are either related to this single mass
parameter or dynamically generated.
| [
{
"created": "Thu, 5 Feb 2009 20:39:55 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Mar 2009 19:25:44 GMT",
"version": "v2"
}
] | 2010-04-23 | [
[
"Brax",
"Philippe",
""
],
[
"Savoy",
"Carlos A.",
""
],
[
"Sil",
"Arunansu",
""
]
] | A model of generalised hybrid inflation in a supersymmetric QCD theory is proposed whose parameters are the gauge coupling and quark masses. Its gravitational coupling to another SQCD sector induces a metastable supersymmetry breaking vacuum of the ISS type as ISS quarks become massive at the end of inflation. Using a known mechanism with a gravitational breaking of the baryon number and the gauging of flavour symmetries, we find that gauge mediation of supersymmetry breaking is compatible with the dynamics of the inflation sector. Reheating proceeds via the thermalization of the ISS messengers into the standard model states. This setup contains a single dimensionful parameter in the form of a quark mass term in the inflationary sector, i.e. all other scales involved are either related to this single mass parameter or dynamically generated. |
hep-ph/0111094 | Kwei-Chou Yang | Hai-Yang Cheng (AS), Yong-Yeon Keum (AS), Kwei-Chou Yang (CYCU) | B -> J/psi K^* Decays in QCD Factorization | 21 pages, 1 figure, a table and a reference added, some typos
corrected | Phys.Rev.D65:094023,2002 | 10.1103/PhysRevD.65.094023 | IPAS-HEP-01-007, KIAS-P01050 | hep-ph | null | The hadronic decay B -> J K^* is analyzed within the framework of QCD
factorization. The spin amplitudes A_0, A_\parallel and A_\perp in the
transversity basis and their relative phases are studied using various
different form-factor models for B-K^* transition. The effective parameters
a_2^h for helicity h=0,+,- states receive different nonfactorizable
contributions and hence they are helicity dependent, contrary to naive
factorization where a_2^h are universal and polarization independent. QCD
factorization breaks down even at the twist-2 level for transverse hard
spectator interactions. Although a nontrivial strong phase for the A_\parallel
amplitude can be achieved by adjusting the phase of an infrared divergent
contribution, the present QCD factorization calculation cannot say anything
definite about the phase phi_\parallel. Unlike B -> J/psi K decays, the
longitudinal parameter a_2^0 for B -> J/psi K^* does not receive twist-3
corrections and is not large enough to account for the observed branching ratio
and the fraction of longitudinal polarization. Possible enhancement mechanisms
for a_2^0 are discussed.
| [
{
"created": "Thu, 8 Nov 2001 17:23:59 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Feb 2002 00:44:52 GMT",
"version": "v2"
}
] | 2011-03-23 | [
[
"Cheng",
"Hai-Yang",
"",
"AS"
],
[
"Keum",
"Yong-Yeon",
"",
"AS"
],
[
"Yang",
"Kwei-Chou",
"",
"CYCU"
]
] | The hadronic decay B -> J K^* is analyzed within the framework of QCD factorization. The spin amplitudes A_0, A_\parallel and A_\perp in the transversity basis and their relative phases are studied using various different form-factor models for B-K^* transition. The effective parameters a_2^h for helicity h=0,+,- states receive different nonfactorizable contributions and hence they are helicity dependent, contrary to naive factorization where a_2^h are universal and polarization independent. QCD factorization breaks down even at the twist-2 level for transverse hard spectator interactions. Although a nontrivial strong phase for the A_\parallel amplitude can be achieved by adjusting the phase of an infrared divergent contribution, the present QCD factorization calculation cannot say anything definite about the phase phi_\parallel. Unlike B -> J/psi K decays, the longitudinal parameter a_2^0 for B -> J/psi K^* does not receive twist-3 corrections and is not large enough to account for the observed branching ratio and the fraction of longitudinal polarization. Possible enhancement mechanisms for a_2^0 are discussed. |
1001.1940 | Jae Yong Lee | Jae Yong Lee | Renormalization in General Gauge Mediation | 25 pages, 12 figures | JHEP 1010:041,2010 | 10.1007/JHEP10(2010)041 | KIAS-P09067 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit General Gauge Mediation (GGM) in light of the supersymmetric
(linear) sigma model by utilizing the current superfield. The current
superfield in the GGM is identified with supersymmetric extension of the vector
symmetry current of the sigma model while spontaneous breakdown of
supersymmetry in the GGM corresponds to soft breakdown of the axial vector
symmetry of the sigma model. We first derive the current superfield from the
supersymmetric linear sigma model and then compute 2-point functions of the
current superfield using the (anti-)commutation relations of the messenger
component fields. After the global symmetry are weakly gauged, the 2-point
functions of the current superfield are identified with a part of the 2-point
functions of the associated vector superfield. We renormalize them by
dimensional regularization and show that physical gaugino and sfermion masses
of the MSSM are expressed in terms of the wavefunction renormalization
constants of the component fields of the vector superfield.
| [
{
"created": "Tue, 12 Jan 2010 16:20:42 GMT",
"version": "v1"
},
{
"created": "Sat, 23 Jan 2010 10:03:41 GMT",
"version": "v2"
},
{
"created": "Thu, 15 Jul 2010 09:31:31 GMT",
"version": "v3"
}
] | 2014-11-20 | [
[
"Lee",
"Jae Yong",
""
]
] | We revisit General Gauge Mediation (GGM) in light of the supersymmetric (linear) sigma model by utilizing the current superfield. The current superfield in the GGM is identified with supersymmetric extension of the vector symmetry current of the sigma model while spontaneous breakdown of supersymmetry in the GGM corresponds to soft breakdown of the axial vector symmetry of the sigma model. We first derive the current superfield from the supersymmetric linear sigma model and then compute 2-point functions of the current superfield using the (anti-)commutation relations of the messenger component fields. After the global symmetry are weakly gauged, the 2-point functions of the current superfield are identified with a part of the 2-point functions of the associated vector superfield. We renormalize them by dimensional regularization and show that physical gaugino and sfermion masses of the MSSM are expressed in terms of the wavefunction renormalization constants of the component fields of the vector superfield. |
hep-ph/0612192 | Bingsong Zou | B.C.Liu and B.S.Zou | Reply to Comment on "Mass and K-Lambda Coupling of the N*(1535)" | accepted by Phys. Rev. Lett. for publication | Phys.Rev.Lett.98:039102,2007 | 10.1103/PhysRevLett.98.039102 | null | hep-ph | null | Here we give our reply to the comment by Sibirtsev et al on our paper ``Mass
and K-Lambda Coupling of the N*(1535)".
| [
{
"created": "Fri, 15 Dec 2006 13:28:24 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Liu",
"B. C.",
""
],
[
"Zou",
"B. S.",
""
]
] | Here we give our reply to the comment by Sibirtsev et al on our paper ``Mass and K-Lambda Coupling of the N*(1535)". |
hep-ph/0501173 | Michael Lublinsky | Eugene Levin and Michael Lublinsky | Towards a symmetric approach to high energy evolution: generating
functional with Pomeron loops | 27 pages and 5 figures. Significantly revised version. To appear in
Nuclear Physics A | Nucl.Phys. A763 (2005) 172-196 | 10.1016/j.nuclphysa.2005.08.021 | TAUP 2795-05 | hep-ph | null | We derive an evolution equation for the generating functional which accounts
for processes for both gluon emission and recombination. In terms of color
dipoles, the kernel of this equation describes evolution as a classical
branching process with conserved probabilities. The introduction of dipole
recombination allows one to obtained closed loops during the evolution, which
should be interpreted as Pomeron loops of the BFKL Pomerons. In comparison with
the emission, the dipole recombination is formally $1/N_c^2$ suppressed. This
suppression, nevertheless, is compensated at very high energies when the
scattering amplitude tends to its unitarity bound.
| [
{
"created": "Tue, 18 Jan 2005 20:26:02 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Jan 2005 01:17:03 GMT",
"version": "v2"
},
{
"created": "Wed, 9 Feb 2005 16:41:39 GMT",
"version": "v3"
},
{
"created": "Tue, 23 Aug 2005 21:18:15 GMT",
"version": "v4"
}
] | 2009-11-11 | [
[
"Levin",
"Eugene",
""
],
[
"Lublinsky",
"Michael",
""
]
] | We derive an evolution equation for the generating functional which accounts for processes for both gluon emission and recombination. In terms of color dipoles, the kernel of this equation describes evolution as a classical branching process with conserved probabilities. The introduction of dipole recombination allows one to obtained closed loops during the evolution, which should be interpreted as Pomeron loops of the BFKL Pomerons. In comparison with the emission, the dipole recombination is formally $1/N_c^2$ suppressed. This suppression, nevertheless, is compensated at very high energies when the scattering amplitude tends to its unitarity bound. |
2204.06484 | Mathew Thomas Mr. | Mathew Thomas Arun | Baryon number violation from confining New Physics | 11 pages, 8 figures, accepted for publishing in Physical Review D | null | 10.1088/1742-6596/2446/1/012052 | null | hep-ph astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | The detection of neutron-antineutron oscillation will be a discovery of
fundamental importance in particle physics and cosmology. In models discussed
widely in literature, the process is generated through heavy New Physics with
weak, perturbative, coupling at the scale of the experiment. Acknowledging the
fact that Nature has been quite evasive regarding the strength and scale of New
Physics, we discuss a new mechanism, generated by confining New Physics, at
$\sim 2$ GeV, resulting in low-energy baryon number violating effects. The
mechanism predicts baryon number violating processes like neutron
disappearance, neutron-neutron annihilation and neutron-anti neutron
oscillation generated through the condensation of the linear moose.
| [
{
"created": "Wed, 13 Apr 2022 16:12:03 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Jul 2022 10:40:23 GMT",
"version": "v2"
},
{
"created": "Tue, 28 Feb 2023 06:04:18 GMT",
"version": "v3"
}
] | 2023-03-22 | [
[
"Arun",
"Mathew Thomas",
""
]
] | The detection of neutron-antineutron oscillation will be a discovery of fundamental importance in particle physics and cosmology. In models discussed widely in literature, the process is generated through heavy New Physics with weak, perturbative, coupling at the scale of the experiment. Acknowledging the fact that Nature has been quite evasive regarding the strength and scale of New Physics, we discuss a new mechanism, generated by confining New Physics, at $\sim 2$ GeV, resulting in low-energy baryon number violating effects. The mechanism predicts baryon number violating processes like neutron disappearance, neutron-neutron annihilation and neutron-anti neutron oscillation generated through the condensation of the linear moose. |
2101.10274 | Antonio Ortiz | Antonio Ortiz and Erik Zepeda | Extraction of the multiplicity dependence of Multiparton Interactions
from LHC pp data using Machine Learning techniques | 4 pages, 4 figures. To be published in Journ. of Phys. G: Nucl. and
Part. Phys | J. Phys. G: Nucl. Part. Phys. 48 (2021) 085014 | 10.1088/1361-6471/abef1e | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Over the last years, Machine Learning (ML) methods have been successfully
applied to a wealth of problems in high-energy physics. For instance, in a
previous work we have reported that using ML techniques one can extract the
Multiparton Interactions (MPI) activity from minimum-bias pp data. Using the
available LHC data on transverse momentum spectra as a function of
multiplicity, we reported the average number of MPI ($\langle N_{\rm mpi}
\rangle$) for minimum-bias pp collisions at $\sqrt{s}=5.02$ and 13\,TeV. In
this work, we apply the same analysis to a new set of data. We report that
$\langle N_{\rm mpi} \rangle$ amounts to $3.98 \pm 1.01$ for minimum-bias pp
collisions at $\sqrt{s}=7$\,TeV. These complementary results suggest a modest
center-of-mass energy dependence of $\langle N_{\rm mpi} \rangle$. The study is
further extended aimed at extracting the multiplicity dependence of $\langle
N_{\rm mpi} \rangle$ for the three center-of-mass energies. We show that our
results qualitatively agree with existing ALICE measurements sensitive to MPI.
Namely, $\langle N_{\rm mpi} \rangle$ increases approximately linearly with the
charged-particle multiplicity. But, it deviates from the linear dependence at
large charged-particle multiplicities. The deviation from the linear trend can
be explained in terms of a bias towards harder processes given the multiplicity
selection at mid-pseudorapidity. The results reported in this paper provide
additional evidence of the presence of MPI in pp collisions, and they can be
useful for a better understanding of the heavy-ion-like behaviour observed in
pp data.
| [
{
"created": "Mon, 25 Jan 2021 17:56:12 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Mar 2021 22:54:23 GMT",
"version": "v2"
}
] | 2021-07-15 | [
[
"Ortiz",
"Antonio",
""
],
[
"Zepeda",
"Erik",
""
]
] | Over the last years, Machine Learning (ML) methods have been successfully applied to a wealth of problems in high-energy physics. For instance, in a previous work we have reported that using ML techniques one can extract the Multiparton Interactions (MPI) activity from minimum-bias pp data. Using the available LHC data on transverse momentum spectra as a function of multiplicity, we reported the average number of MPI ($\langle N_{\rm mpi} \rangle$) for minimum-bias pp collisions at $\sqrt{s}=5.02$ and 13\,TeV. In this work, we apply the same analysis to a new set of data. We report that $\langle N_{\rm mpi} \rangle$ amounts to $3.98 \pm 1.01$ for minimum-bias pp collisions at $\sqrt{s}=7$\,TeV. These complementary results suggest a modest center-of-mass energy dependence of $\langle N_{\rm mpi} \rangle$. The study is further extended aimed at extracting the multiplicity dependence of $\langle N_{\rm mpi} \rangle$ for the three center-of-mass energies. We show that our results qualitatively agree with existing ALICE measurements sensitive to MPI. Namely, $\langle N_{\rm mpi} \rangle$ increases approximately linearly with the charged-particle multiplicity. But, it deviates from the linear dependence at large charged-particle multiplicities. The deviation from the linear trend can be explained in terms of a bias towards harder processes given the multiplicity selection at mid-pseudorapidity. The results reported in this paper provide additional evidence of the presence of MPI in pp collisions, and they can be useful for a better understanding of the heavy-ion-like behaviour observed in pp data. |
1611.08149 | Stefan Groote Dr. | Sergey Koshkarev, Stefan Groote | Double quarkonium production at high Feynman-$x$ | 11 pages, 2 figures, version to be published | Nucl. Phys. B915 (2017) 384-391 | 10.1016/j.nuclphysb.2016.12.018 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we give estimates for the proton--proton cross sections into
pairs of quarkonium states $J/\psi$, $\psi(2S)$, $\Upsilon(1S)$ and
$\Upsilon(2S)$ at the scheduled AFTER@LHC energy of $115$GeV. The estimates are
based on the intrinsic heavy flavor mechanism which is observable for high
values of $x_F$, a range outside the dominance of single parton and double
parton scattering.
| [
{
"created": "Thu, 24 Nov 2016 11:28:43 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Jan 2017 19:25:16 GMT",
"version": "v2"
}
] | 2017-01-17 | [
[
"Koshkarev",
"Sergey",
""
],
[
"Groote",
"Stefan",
""
]
] | In this paper we give estimates for the proton--proton cross sections into pairs of quarkonium states $J/\psi$, $\psi(2S)$, $\Upsilon(1S)$ and $\Upsilon(2S)$ at the scheduled AFTER@LHC energy of $115$GeV. The estimates are based on the intrinsic heavy flavor mechanism which is observable for high values of $x_F$, a range outside the dominance of single parton and double parton scattering. |
1412.4515 | Roberto Onofrio | Roberto Onofrio | High-energy density implications of a gravitoweak unification scenario | null | Modern Physics Letters A 29, 1350187 (2014) | 10.1142/S0217732313501873 | null | hep-ph gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss how a scenario recently proposed for the morphing of macroscopic
gravitation into weak interactions at the attometer scale affects our current
understanding of high-energy density phenomena. We find that the Yukawa
couplings of the fundamental fermions are directly related to their event
horizons, setting an upper bound $y_f\leq \sqrt{2}$ for their observability
through gauge interactions. Particles with larger Yukawa couplings are not
precluded, but should interact only gravitationally, providing a natural
candidate for dark matter. Furthermore, the quantum vacuum contribution to the
cosmological constant is reduced by several orders of magnitude with respect to
the current estimates. The expected running of the Newtonian gravitational
constant could provide a viable alternative scenario to the inflationary stage
of the Universe.
| [
{
"created": "Mon, 15 Dec 2014 10:00:36 GMT",
"version": "v1"
}
] | 2014-12-16 | [
[
"Onofrio",
"Roberto",
""
]
] | We discuss how a scenario recently proposed for the morphing of macroscopic gravitation into weak interactions at the attometer scale affects our current understanding of high-energy density phenomena. We find that the Yukawa couplings of the fundamental fermions are directly related to their event horizons, setting an upper bound $y_f\leq \sqrt{2}$ for their observability through gauge interactions. Particles with larger Yukawa couplings are not precluded, but should interact only gravitationally, providing a natural candidate for dark matter. Furthermore, the quantum vacuum contribution to the cosmological constant is reduced by several orders of magnitude with respect to the current estimates. The expected running of the Newtonian gravitational constant could provide a viable alternative scenario to the inflationary stage of the Universe. |
hep-ph/0406241 | Jeppe R. Andersen | Jeppe R. Andersen | New possibilities in the study of NLL BFKL | 5 pages, presented at the XXXIXth Rencontres de Moriond, QCD and
Hadronic interactions, La Thuile, Italy | null | null | Cavendish-HEP-04-18, DAMTP-2004-65 | hep-ph | null | The high energy limit of scattering processes in QCD is, at least on the
purely theoretical level, described by the BFKL equation. However, many
phenomenological studies of BFKL fail miserably when confronted with data. In
this talk we will briefly review the application of (LL) BFKL in phenomenology,
and critically examine the application of LL eigenfunctions in the study of the
NLL BFKL kernel. We then introduce a recently proposed iterative solution of
the NLL BFKL equation that allows for a detailed study of physical properties
of the BFKL evolution.
| [
{
"created": "Tue, 22 Jun 2004 14:56:17 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Andersen",
"Jeppe R.",
""
]
] | The high energy limit of scattering processes in QCD is, at least on the purely theoretical level, described by the BFKL equation. However, many phenomenological studies of BFKL fail miserably when confronted with data. In this talk we will briefly review the application of (LL) BFKL in phenomenology, and critically examine the application of LL eigenfunctions in the study of the NLL BFKL kernel. We then introduce a recently proposed iterative solution of the NLL BFKL equation that allows for a detailed study of physical properties of the BFKL evolution. |
hep-ph/9805460 | Yuji Koike | Y. Koike, N. Nishiyama (Niigata Univ.) and K. Tanaka (Juntendo Univ.) | Renormalization of Chiral-Even Twist-3 Light-cone Wave Functions for
Vector Mesons in QCD | 9 pages in Latex. No figures. Submitted to Phys. Lett. B | Phys.Lett. B437 (1998) 153-159 | 10.1016/S0370-2693(98)00901-0 | null | hep-ph | null | We present the one-loop anomalous dimension matrices for the chiral-even
twist-3 (nonsinglet) conformal operators, which govern the scale-dependence of
the vector meson light-cone wave functions through the conformal expansion. It
is clarified that the constraints from the charge-conjugation invariance and
the chirality conservation allow only one independent anomalous dimension
matrix for each conformal spin.
| [
{
"created": "Tue, 26 May 1998 09:59:08 GMT",
"version": "v1"
},
{
"created": "Wed, 27 May 1998 03:40:42 GMT",
"version": "v2"
},
{
"created": "Thu, 28 May 1998 06:31:53 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Koike",
"Y.",
"",
"Niigata Univ."
],
[
"Nishiyama",
"N.",
"",
"Niigata Univ."
],
[
"Tanaka",
"K.",
"",
"Juntendo Univ."
]
] | We present the one-loop anomalous dimension matrices for the chiral-even twist-3 (nonsinglet) conformal operators, which govern the scale-dependence of the vector meson light-cone wave functions through the conformal expansion. It is clarified that the constraints from the charge-conjugation invariance and the chirality conservation allow only one independent anomalous dimension matrix for each conformal spin. |
1503.05683 | Kochelev Nikolai Innokentevich | Nikolai Kochelev, Hee-Jung Lee, Baiyang Zhang and Pengming Zhang | Anomalous pion production induced by nontrivial topological structure of
QCD vacuum | 5 pages, 4 figures, final version published in Phys.Rev.D92,034025
(2015) | Phys. Rev. D 92, 034025 (2015) | 10.1103/PhysRevD.92.034025 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new mechanism for the pion production in the high energy reactions is
suggested. It is related to the possibility for direct production of the pions
induced by instantons, topologically nontrivial gluonic excitations of QCD
vacuum. This mechanism does not require any fragmentation functions for
production of pseudoscalar mesons in high energy reactions with hadrons. We
calculate the contribution of a new mechanism to the inclusive $\pi^0$-meson
production in high energy proton-proton collision. It is shown that it gives
the dominated contribution to the inclusive cross-sections in the few GeV
region for the transverse momentum of final pion. We discuss the possible
application of a new mechanism to the phenomenon of the large spin effects
observed in the numerous high energy reactions.
| [
{
"created": "Thu, 19 Mar 2015 09:52:43 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Mar 2015 23:58:11 GMT",
"version": "v2"
},
{
"created": "Mon, 31 Aug 2015 07:32:35 GMT",
"version": "v3"
}
] | 2015-09-02 | [
[
"Kochelev",
"Nikolai",
""
],
[
"Lee",
"Hee-Jung",
""
],
[
"Zhang",
"Baiyang",
""
],
[
"Zhang",
"Pengming",
""
]
] | A new mechanism for the pion production in the high energy reactions is suggested. It is related to the possibility for direct production of the pions induced by instantons, topologically nontrivial gluonic excitations of QCD vacuum. This mechanism does not require any fragmentation functions for production of pseudoscalar mesons in high energy reactions with hadrons. We calculate the contribution of a new mechanism to the inclusive $\pi^0$-meson production in high energy proton-proton collision. It is shown that it gives the dominated contribution to the inclusive cross-sections in the few GeV region for the transverse momentum of final pion. We discuss the possible application of a new mechanism to the phenomenon of the large spin effects observed in the numerous high energy reactions. |
2304.14855 | Manuel Pavon Valderrama | Mao-Jun Yan, Fang-Zheng Peng, Manuel Pavon Valderrama | Molecular charmed baryons and pentaquarks from light-meson exchange
saturation | 14 pages, 6 tables | null | null | null | hep-ph hep-ex hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The spectrum of the $c qq$ baryons contains a few states whose nature is not
clearly a three-quark composite and which might have a sizable baryon-meson
component. Examples include the $\Sigma_c(2800)$ or the $\Lambda_c(2940)$. Here
we explore the spectrum of two-body systems composed of a light, octet baryon
and a charmed meson (or antimeson) within a simple contact-range theory in
which the couplings are saturated by light-meson exchanges. This results in the
prediction of a series of composite anticharmed pentaquarks ($\bar{c} q qqq $)
and singly-charmed baryons ($c \bar{q} qqq $). Among the later we find
$J=\tfrac{1}{2}$ $\Xi D$ and $J=\tfrac{3}{2}$ $\Xi D^*$ bound states with
masses matching those of the recently observed $\Omega_c(3185)$ and
$\Omega_c(3327)$ baryons.
| [
{
"created": "Fri, 28 Apr 2023 14:06:13 GMT",
"version": "v1"
}
] | 2023-05-01 | [
[
"Yan",
"Mao-Jun",
""
],
[
"Peng",
"Fang-Zheng",
""
],
[
"Valderrama",
"Manuel Pavon",
""
]
] | The spectrum of the $c qq$ baryons contains a few states whose nature is not clearly a three-quark composite and which might have a sizable baryon-meson component. Examples include the $\Sigma_c(2800)$ or the $\Lambda_c(2940)$. Here we explore the spectrum of two-body systems composed of a light, octet baryon and a charmed meson (or antimeson) within a simple contact-range theory in which the couplings are saturated by light-meson exchanges. This results in the prediction of a series of composite anticharmed pentaquarks ($\bar{c} q qqq $) and singly-charmed baryons ($c \bar{q} qqq $). Among the later we find $J=\tfrac{1}{2}$ $\Xi D$ and $J=\tfrac{3}{2}$ $\Xi D^*$ bound states with masses matching those of the recently observed $\Omega_c(3185)$ and $\Omega_c(3327)$ baryons. |
1608.06470 | Mateo Garcia Pepin | Antonio Delgado, Mateo Garcia-Pepin, Germano Nardini, Mariano Quiros | Natural Supersymmetry from Extra Dimensions | 34 pages, 12 figures; v2, matches PRD published version | Phys. Rev. D 94, 095017 (2016) | 10.1103/PhysRevD.94.095017 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that natural supersymmetry can be embedded in a five-dimensional
theory with supersymmetry breaking \`a la Scherk-Schwarz (SS). There is no
'gluino-sucks' problem for stops localized in the four-dimensional brane and
gluinos propagating in the full five-dimensional bulk, and sub-TeV stops are
easily accommodated. The $\mu / B_\mu$ problem is absent as well; the SS
breaking generates a Higgsino Dirac mass and no bilinear Higgs mass parameter
in the superpotential is required. Moreover, for non-maximal SS twists leading
to $\tan \beta \simeq 1$, the Higgs spectrum is naturally split, in agreement
with LHC data. The 125-GeV Higgs mass and radiative electroweak symmetry
breaking can be accommodated by minimally extending the Higgs sector with $Y=0$
$SU(2)_L$ triplets.
| [
{
"created": "Tue, 23 Aug 2016 11:33:05 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Dec 2016 13:36:00 GMT",
"version": "v2"
}
] | 2016-12-08 | [
[
"Delgado",
"Antonio",
""
],
[
"Garcia-Pepin",
"Mateo",
""
],
[
"Nardini",
"Germano",
""
],
[
"Quiros",
"Mariano",
""
]
] | We show that natural supersymmetry can be embedded in a five-dimensional theory with supersymmetry breaking \`a la Scherk-Schwarz (SS). There is no 'gluino-sucks' problem for stops localized in the four-dimensional brane and gluinos propagating in the full five-dimensional bulk, and sub-TeV stops are easily accommodated. The $\mu / B_\mu$ problem is absent as well; the SS breaking generates a Higgsino Dirac mass and no bilinear Higgs mass parameter in the superpotential is required. Moreover, for non-maximal SS twists leading to $\tan \beta \simeq 1$, the Higgs spectrum is naturally split, in agreement with LHC data. The 125-GeV Higgs mass and radiative electroweak symmetry breaking can be accommodated by minimally extending the Higgs sector with $Y=0$ $SU(2)_L$ triplets. |
hep-ph/0607158 | Geraldine Servant | Lisa Randall and Geraldine Servant | Gravitational Waves from Warped Spacetime | 18 pages, 15 figures; v2: discussion improved, in particular on the
justification of the thick wall approximation. 6 figures added. 4 pi factor
corrected in perturbativity bound. N-dependence displayed. Conclusions
unchanged. JHEP version | JHEP 0705:054,2007 | 10.1088/1126-6708/2007/05/054 | CERN-PH-TH/2006-133 | hep-ph astro-ph gr-qc hep-th | null | We argue that the RSI model can provide a strong signature in gravitational
waves. This signal is a relic stochastic background generated during the
cosmological phase transition from an AdS-Schwarschild phase to the RS1
geometry that should occur at a temperature in the TeV range. We estimate the
amplitude of the signal in terms of the parameters of the potential stabilizing
the radion and show that over much of the parameter region in which the phase
transition completes, a signal should be detectable at the planned space
interferometer, LISA.
| [
{
"created": "Fri, 14 Jul 2006 08:41:22 GMT",
"version": "v1"
},
{
"created": "Fri, 4 May 2007 10:12:29 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Randall",
"Lisa",
""
],
[
"Servant",
"Geraldine",
""
]
] | We argue that the RSI model can provide a strong signature in gravitational waves. This signal is a relic stochastic background generated during the cosmological phase transition from an AdS-Schwarschild phase to the RS1 geometry that should occur at a temperature in the TeV range. We estimate the amplitude of the signal in terms of the parameters of the potential stabilizing the radion and show that over much of the parameter region in which the phase transition completes, a signal should be detectable at the planned space interferometer, LISA. |
2303.06576 | Evan Grohs | E. Grohs, A. B. Balantekin | Implications on Cosmology from Dirac Neutrino Magnetic Moments | 22 pages, 3 appendices, 14 figures. Contains updated list of
references and corrections to typos. Matches version accepted in Phys. Rev. D | null | 10.1103/PhysRevD.107.123502 | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | The mechanism for generating neutrino masses remains a puzzle in particle
physics. If neutrino masses follow from a Dirac mass term, then neutrino states
exist with opposite chirality compared to their weakly-interacting
counterparts. These inactive states do not interact with their active
counterparts at measurable scales in the standard model. However, the existence
of these states can have implications for cosmology as they contribute to the
radiation energy density at early times, and the matter energy density at late
times. How Dirac neutrinos may populate thermal states via an anomalous
magnetic moment operator is the focus of this work. A class of models where all
neutrinos have a magnetic moment independent of flavor or chirality is
considered. Subsequently, the cross sections for neutrinos scattering on
background plasma particles are calculated so that the relic inactive neutrino
energy is derived as a function of plasma temperature. To do so, one needs
cross sections for scattering on all electrically charged standard-model
particles. Therefore, the scattering cross section between a neutrino and
$W$-boson via the magnetic moment vertex is derived. Current measurements put a
constraint on the size of the neutrino magnetic moment from the cosmological
parameter $N_{\rm eff}$ and light-element primordial abundances. Finally, how
the extra Dirac states contribute to the matter energy density at late times is
investigated by examining neutrino free-streaming.
| [
{
"created": "Sun, 12 Mar 2023 05:17:39 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Mar 2023 23:40:51 GMT",
"version": "v2"
},
{
"created": "Fri, 19 May 2023 09:14:07 GMT",
"version": "v3"
}
] | 2023-06-14 | [
[
"Grohs",
"E.",
""
],
[
"Balantekin",
"A. B.",
""
]
] | The mechanism for generating neutrino masses remains a puzzle in particle physics. If neutrino masses follow from a Dirac mass term, then neutrino states exist with opposite chirality compared to their weakly-interacting counterparts. These inactive states do not interact with their active counterparts at measurable scales in the standard model. However, the existence of these states can have implications for cosmology as they contribute to the radiation energy density at early times, and the matter energy density at late times. How Dirac neutrinos may populate thermal states via an anomalous magnetic moment operator is the focus of this work. A class of models where all neutrinos have a magnetic moment independent of flavor or chirality is considered. Subsequently, the cross sections for neutrinos scattering on background plasma particles are calculated so that the relic inactive neutrino energy is derived as a function of plasma temperature. To do so, one needs cross sections for scattering on all electrically charged standard-model particles. Therefore, the scattering cross section between a neutrino and $W$-boson via the magnetic moment vertex is derived. Current measurements put a constraint on the size of the neutrino magnetic moment from the cosmological parameter $N_{\rm eff}$ and light-element primordial abundances. Finally, how the extra Dirac states contribute to the matter energy density at late times is investigated by examining neutrino free-streaming. |
0807.3921 | Leone Cavicchia | Leone Cavicchia | The NMSSM with m_h > 115 GeV and a moderate stop mass | 21 pages, 12 figures; 2 references added, minor changes in text | null | 10.1016/j.nuclphysb.2008.12.027 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the generic NMSSM with the coupling \lambda S H_1 H_2 at the limit
of perturbativity, \lambda~0.7-0.8, and a moderate stop mass, m_{\tilde{t}} <
300 GeV. Respecting the LEP2 bounds and insisting on naturalness, we delimit
the allowed region of parameter space and we study the spectrum and
phenomenology of the relatively light new particles.
| [
{
"created": "Thu, 24 Jul 2008 16:55:30 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Sep 2008 13:59:16 GMT",
"version": "v2"
},
{
"created": "Fri, 17 Oct 2008 17:31:30 GMT",
"version": "v3"
}
] | 2009-11-13 | [
[
"Cavicchia",
"Leone",
""
]
] | We study the generic NMSSM with the coupling \lambda S H_1 H_2 at the limit of perturbativity, \lambda~0.7-0.8, and a moderate stop mass, m_{\tilde{t}} < 300 GeV. Respecting the LEP2 bounds and insisting on naturalness, we delimit the allowed region of parameter space and we study the spectrum and phenomenology of the relatively light new particles. |
hep-ph/9801325 | Wilhelmus van Neerven | W.L. van Neerven | Second order QCD contributions to polarized spacelike and timelike
processes | 11 pages Latex, style file included. | Acta Phys.Polon. B29 (1998) 1175-1188 | null | DESY 98-006 | hep-ph | null | We will give an outline of the computation of the QCD corrections to the spin
structure function g_1(x,Q^2) and the spin fragmentation function g_1^H(x,Q^2)
which are measured in deep inelastic electron-proton scattering and in
electron-positron annihilation respectively. In particular we show how to deal
with the gamma_5-matrix and the Levi-Civita tensor, appearing in the amplitudes
of the parton subprocesses, when the method of N-dimensional regularization is
used.
| [
{
"created": "Fri, 16 Jan 1998 13:40:11 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"van Neerven",
"W. L.",
""
]
] | We will give an outline of the computation of the QCD corrections to the spin structure function g_1(x,Q^2) and the spin fragmentation function g_1^H(x,Q^2) which are measured in deep inelastic electron-proton scattering and in electron-positron annihilation respectively. In particular we show how to deal with the gamma_5-matrix and the Levi-Civita tensor, appearing in the amplitudes of the parton subprocesses, when the method of N-dimensional regularization is used. |
1405.7770 | Axel Weber | F. Bastianelli, A. Huet, C. Schubert, R. Thakur, A. Weber | Integral representations combining ladders and crossed-ladders | 39 pages, 10 pdf figures | null | 10.1007/JHEP07(2014)066 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use the worldline formalism to derive integral representations for three
classes of amplitudes in scalar field theory: (i) the scalar propagator
exchanging N momenta with a scalar background field (ii) the "half-ladder" with
N rungs in x - space (iii) the four-point ladder with N rungs in x - space as
well as in (off-shell) momentum space. In each case we give a compact
expression combining the N! Feynman diagrams contributing to the amplitude. As
our main application, we reconsider the well-known case of two massive scalars
interacting through the exchange of a massless scalar. Applying asymptotic
estimates and a saddle-point approximation to the N-rung ladder plus crossed
ladder diagrams, we derive a semi-analytic approximation formula for the lowest
bound state mass in this model.
| [
{
"created": "Fri, 30 May 2014 04:30:47 GMT",
"version": "v1"
}
] | 2015-06-19 | [
[
"Bastianelli",
"F.",
""
],
[
"Huet",
"A.",
""
],
[
"Schubert",
"C.",
""
],
[
"Thakur",
"R.",
""
],
[
"Weber",
"A.",
""
]
] | We use the worldline formalism to derive integral representations for three classes of amplitudes in scalar field theory: (i) the scalar propagator exchanging N momenta with a scalar background field (ii) the "half-ladder" with N rungs in x - space (iii) the four-point ladder with N rungs in x - space as well as in (off-shell) momentum space. In each case we give a compact expression combining the N! Feynman diagrams contributing to the amplitude. As our main application, we reconsider the well-known case of two massive scalars interacting through the exchange of a massless scalar. Applying asymptotic estimates and a saddle-point approximation to the N-rung ladder plus crossed ladder diagrams, we derive a semi-analytic approximation formula for the lowest bound state mass in this model. |
hep-ph/0009071 | Robert Perry | Sergio Szpigel and Robert J. Perry | The Similarity Renormalization Group | 28 pages, 7 postscript figures | Published in Quantum Field Theory, A 20th Century Profile | null | null | hep-ph hep-th nucl-th | null | Quantum field theories require a cutoff to regulate divergences that result
from local interactions, and yet physical results can not depend on the value
of this cutoff. The renormalization group employs a transformation that changes
the cutoff to isolate hamiltonians that produce cutoff-independent eigenvalues.
The similarity renormalization group is based on similarity transformations
that regulate off-diagonal matrix elements, forcing the hamiltonian towards a
band-diagonal form as the cutoff is lowered. This avoids pathologies that
plagued tradition transformations acting on hamiltonians, making it possible to
produce a well-behaved perturbative approximation of renormalized hamiltonians
in asymptotically free theories. We employ a simple two-dimensional delta
function example to illustrate this new renormalization technique.
| [
{
"created": "Wed, 6 Sep 2000 16:49:19 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Szpigel",
"Sergio",
""
],
[
"Perry",
"Robert J.",
""
]
] | Quantum field theories require a cutoff to regulate divergences that result from local interactions, and yet physical results can not depend on the value of this cutoff. The renormalization group employs a transformation that changes the cutoff to isolate hamiltonians that produce cutoff-independent eigenvalues. The similarity renormalization group is based on similarity transformations that regulate off-diagonal matrix elements, forcing the hamiltonian towards a band-diagonal form as the cutoff is lowered. This avoids pathologies that plagued tradition transformations acting on hamiltonians, making it possible to produce a well-behaved perturbative approximation of renormalized hamiltonians in asymptotically free theories. We employ a simple two-dimensional delta function example to illustrate this new renormalization technique. |
hep-ph/0511274 | Joaquim Matias | Joaquim Matias | The Angular Distribution of B0-> K*0(->K-pi+)l+l- at Large Recoil in and
Beyond the SM | 4 pages, 4 figures | PoS HEP2005:281,2006 | null | null | hep-ph | null | We discuss, in detail, the K* polarization states in the exclusive B meson
decay B0-> K*0(-> K-pi+)l^+l^- (l=e, \mu, \tau) in the low dilepton mass
region. We focus on the study of the angular distribution of this decay that
provides valuable information on the K* spin amplitudes A_perp, A_par, A0. This
can give us a handle on non-standard interactions that cannot be proved through
measurements of the branching ratio and lepton forward-backward asymmetry. We
explore the transverse asymmetries A_T^1(s), A_T^2(s), K* polarization
parameter \alpha_{K*}(s), the fraction of K* polarization F_L(s) and F_T(s) and
the corresponding integrated observables at NLL order, including factorizable
and non-factorizable corrections. We find, in particular, that the dependence
on hadronic uncertainties for the transverse asymmetries turns out to be very
small. This allow us to distinguish which observables are better suited to look
for physics beyond the SM. Finally, we study in a model independent way the
implications of New Physics for these observables.
| [
{
"created": "Wed, 23 Nov 2005 14:23:16 GMT",
"version": "v1"
}
] | 2011-04-11 | [
[
"Matias",
"Joaquim",
""
]
] | We discuss, in detail, the K* polarization states in the exclusive B meson decay B0-> K*0(-> K-pi+)l^+l^- (l=e, \mu, \tau) in the low dilepton mass region. We focus on the study of the angular distribution of this decay that provides valuable information on the K* spin amplitudes A_perp, A_par, A0. This can give us a handle on non-standard interactions that cannot be proved through measurements of the branching ratio and lepton forward-backward asymmetry. We explore the transverse asymmetries A_T^1(s), A_T^2(s), K* polarization parameter \alpha_{K*}(s), the fraction of K* polarization F_L(s) and F_T(s) and the corresponding integrated observables at NLL order, including factorizable and non-factorizable corrections. We find, in particular, that the dependence on hadronic uncertainties for the transverse asymmetries turns out to be very small. This allow us to distinguish which observables are better suited to look for physics beyond the SM. Finally, we study in a model independent way the implications of New Physics for these observables. |
hep-ph/0003315 | Michele Maltoni | M. Maltoni | Bounds on "charginos nearly degenerate with the lightest neutralino"
mass from precision measurements | 4 pages, LaTeX, 1 figure included. Talk given at PASCOS99 conference,
Lake Tahoe, California, December 10-16, 1999 | null | 10.1142/9789812792433_0037 | IFIC/00-20 | hep-ph | null | Though LEP II direct searches still cannot exclude a chargino nearly
degenerate with the lightest neutralino if its mass is only slightly above half
of the Z boson mass and the sneutrino is light, it can be excluded indirectly
analyzing precision data. In this particular limit simple analytical formulas
for oblique electroweak radiative corrections are presented.
| [
{
"created": "Fri, 31 Mar 2000 10:52:22 GMT",
"version": "v1"
}
] | 2016-11-03 | [
[
"Maltoni",
"M.",
""
]
] | Though LEP II direct searches still cannot exclude a chargino nearly degenerate with the lightest neutralino if its mass is only slightly above half of the Z boson mass and the sneutrino is light, it can be excluded indirectly analyzing precision data. In this particular limit simple analytical formulas for oblique electroweak radiative corrections are presented. |
2309.06182 | Herschel A. Chawdhry | Herschel A. Chawdhry and Mathieu Pellen | Quantum algorithms for the simulation of perturbative QCD processes | 10 pages, 1 figure. Contribution to the proceedings of RADCOR 2023 | PoS (RADCOR2023) 087 | null | FR-PHENO-2023-10, OUTP-23-09P | hep-ph hep-th quant-ph | http://creativecommons.org/licenses/by-nc-sa/4.0/ | Quantum computers are expected to give major speed-ups for the simulation of
quantum systems. In these conference proceedings, we discuss quantum algorithms
for the simulation of perturbative Quantum Chromodynamics (QCD) processes. In
particular, we describe quantum circuits for simulating the colour part of the
interactions of quarks and gluons. We implement our circuits on a simulated
noiseless quantum computer and validate them by calculating colour factors for
various examples of Feynman diagrams.
| [
{
"created": "Tue, 12 Sep 2023 12:50:37 GMT",
"version": "v1"
}
] | 2023-09-14 | [
[
"Chawdhry",
"Herschel A.",
""
],
[
"Pellen",
"Mathieu",
""
]
] | Quantum computers are expected to give major speed-ups for the simulation of quantum systems. In these conference proceedings, we discuss quantum algorithms for the simulation of perturbative Quantum Chromodynamics (QCD) processes. In particular, we describe quantum circuits for simulating the colour part of the interactions of quarks and gluons. We implement our circuits on a simulated noiseless quantum computer and validate them by calculating colour factors for various examples of Feynman diagrams. |
2007.14287 | Rico Z\"ollner | R. Z\"ollner, B. Kampfer | Quarkonia formation in a holographic gravity-dilaton background
describing QCD thermodynamics | null | Particles 2021, 4(2), 159 | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A holographic model of probe quarkonia is presented, where the dynamical
gravity-dilaton background is adjusted to the thermodynamics of 2 +1 flavor QCD
with physical quark masses. The quarkonia action is modified to account for a
systematic study of the heavy-quark mass dependence. We focus on the $J/\psi$
and $\Upsilon$ spectral functions and relate our model to heavy quarkonia
formation as a special aspect of hadron phenomenology in heavy-ion collisions
at LHC.
| [
{
"created": "Tue, 28 Jul 2020 14:56:02 GMT",
"version": "v1"
}
] | 2021-04-21 | [
[
"Zöllner",
"R.",
""
],
[
"Kampfer",
"B.",
""
]
] | A holographic model of probe quarkonia is presented, where the dynamical gravity-dilaton background is adjusted to the thermodynamics of 2 +1 flavor QCD with physical quark masses. The quarkonia action is modified to account for a systematic study of the heavy-quark mass dependence. We focus on the $J/\psi$ and $\Upsilon$ spectral functions and relate our model to heavy quarkonia formation as a special aspect of hadron phenomenology in heavy-ion collisions at LHC. |
2408.05265 | Gherardo Vita | John Campbell, Tobias Neumann, and Gherardo Vita | Projection-to-Born-improved Subtractions at NNLO | 24 pages, 15 figures | null | null | CERN-TH-2024-102, FERMILAB-PUB-24-0402-T | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | While the current frontier in fixed-order precision for collider observables
is N$^3$LO, important steps are necessary to consolidate NNLO cross-section
predictions with improved stability and efficiency. Slicing methods have been
successfully applied to obtain NNLO and N$^3$LO predictions, but have shown
poor performance in the presence of fiducial cuts due to large kinematical
power corrections. In this paper we implement Projection-to-Born-improved $q_T$
(P2B $q_T$) and jettiness (P2B $\tau_0$) subtractions for a large class of
color singlet processes in MCFM. This method allows for the efficient
evaluation of \emph{fiducial} power corrections in any non-local subtraction
scheme using a Projection-to-Born subtraction. We demonstrate the significant
numerical improvements of this method based on fiducial Drell-Yan and Higgs
cross-sections. Moreover, with fiducial power corrections removed via this
method, the leading-logarithmic power corrections that have only been
calculated without fiducial cuts can be included, further improving the
calculations. For di-photon production with photon isolation, we devise a novel
method in combination with P2B-improved subtractions, which we name
$P2B_\gamma$ $\tau_0$, and $P2B_\gamma$ $q_T$ for the two subtraction schemes,
respectively. This method allows the inclusion of both fiducial power
corrections due to kinematic cuts on the photons and a set of isolation power
corrections in the fragmentation channel where a quark may enter the isolation
cone. We find significant improvements in the convergence of NNLO di-photon
cross-sections with photon isolation cuts, demonstrating that it is possible to
achieve a stable and efficient calculation of di-photon cross-sections using
slicing methods.
| [
{
"created": "Fri, 9 Aug 2024 18:00:00 GMT",
"version": "v1"
}
] | 2024-08-13 | [
[
"Campbell",
"John",
""
],
[
"Neumann",
"Tobias",
""
],
[
"Vita",
"Gherardo",
""
]
] | While the current frontier in fixed-order precision for collider observables is N$^3$LO, important steps are necessary to consolidate NNLO cross-section predictions with improved stability and efficiency. Slicing methods have been successfully applied to obtain NNLO and N$^3$LO predictions, but have shown poor performance in the presence of fiducial cuts due to large kinematical power corrections. In this paper we implement Projection-to-Born-improved $q_T$ (P2B $q_T$) and jettiness (P2B $\tau_0$) subtractions for a large class of color singlet processes in MCFM. This method allows for the efficient evaluation of \emph{fiducial} power corrections in any non-local subtraction scheme using a Projection-to-Born subtraction. We demonstrate the significant numerical improvements of this method based on fiducial Drell-Yan and Higgs cross-sections. Moreover, with fiducial power corrections removed via this method, the leading-logarithmic power corrections that have only been calculated without fiducial cuts can be included, further improving the calculations. For di-photon production with photon isolation, we devise a novel method in combination with P2B-improved subtractions, which we name $P2B_\gamma$ $\tau_0$, and $P2B_\gamma$ $q_T$ for the two subtraction schemes, respectively. This method allows the inclusion of both fiducial power corrections due to kinematic cuts on the photons and a set of isolation power corrections in the fragmentation channel where a quark may enter the isolation cone. We find significant improvements in the convergence of NNLO di-photon cross-sections with photon isolation cuts, demonstrating that it is possible to achieve a stable and efficient calculation of di-photon cross-sections using slicing methods. |
2403.20044 | Tao Wang | Yang Shi, Towe Wang | Compton scattering in Bandos-Lechner-Sorokin-Townsend nonlinear
electrodynamics | 11 pages, 5 figures | null | null | null | hep-ph physics.optics | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The nonlinear electrodynamics proposed by Bandos, Lechner, Sorokin and
Townsend is a remarkable theory that unifies Maxwell, Bialynicki-Birula and
ModMax theories, which are known theories invariant under conformal
transformations and electromagnetic duality transformations. In the
Bandos-Lechner-Sorokin-Townsend nonlinear electrodynamics, we calculate the
energy flux density, dispersion relations, refractive indices, phase and group
velocities of plane waves as well as the changes of the photon wavelength in
the Compton scattering process in the presence of a constant uniform
electromagnetic background. Our results are useful for testing and constraining
this new theory of nonlinear electrodynamics.
| [
{
"created": "Fri, 29 Mar 2024 08:29:30 GMT",
"version": "v1"
}
] | 2024-04-01 | [
[
"Shi",
"Yang",
""
],
[
"Wang",
"Towe",
""
]
] | The nonlinear electrodynamics proposed by Bandos, Lechner, Sorokin and Townsend is a remarkable theory that unifies Maxwell, Bialynicki-Birula and ModMax theories, which are known theories invariant under conformal transformations and electromagnetic duality transformations. In the Bandos-Lechner-Sorokin-Townsend nonlinear electrodynamics, we calculate the energy flux density, dispersion relations, refractive indices, phase and group velocities of plane waves as well as the changes of the photon wavelength in the Compton scattering process in the presence of a constant uniform electromagnetic background. Our results are useful for testing and constraining this new theory of nonlinear electrodynamics. |
1606.07477 | Stephen Adler | Stephen L. Adler | Coleman-Weinberg symmetry breaking in $SU(8)$ induced by a third rank
antisymmetric tensor scalar field II: the fermion spectrum | Latex, 29 pages; revised and expanded from the initial posting | J. Phys. A: Math. Theor. 50, 295401 (2017) | 10.1088/1751-8121/aa768f | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We continue our study of Coleman-Weinberg symmetry breaking induced by a
third rank antisymmetric tensor scalar, in the context of the $SU(8)$ model we
proposed earlier. We focus in this paper on qualitative features that will
determine whether the model can make contact with the observed particle
spectrum. We discuss the mechanism for giving the spin $\frac{3}{2}$ field a
mass by the BEH mechanism, and analyze the remaining massless spin
$\frac{1}{2}$ fermions, the global chiral symmetries, and the running couplings
after symmetry breaking. We note that the smallest gluon mass matrix eigenvalue
has an eigenvector suggestive of $U(1)_{B-L}$, and conjecture that the theory
runs to an infrared fixed point at which there is a massless gluon with 3 to -1
ratios in generator components. Assuming this, we discuss a mechanism for
making contact with the standard model, based on a conjectured asymmetric
breaking of $Sp(4)$ to $SU(2)$ subgroups, one of which is the electroweak
$SU(2)$, and the other of which is a "technicolor" group that binds the
original $SU(8)$ model fermions, which play the role of "preons", into
composites. Quarks can emerge as 5 preon composites and leptons as 3 preon
composites, with consequent stability of the proton against decay to a single
lepton plus a meson. A composite Higgs boson can emerge as a two preon
composite. Since anomaly matching for the relevant conserved global symmetry
current is not obeyed by three fermion families, emergence of three composite
families requires formation of a Goldstone boson with quantum numbers matching
this current, which can be a light dark matter candidate.
| [
{
"created": "Thu, 23 Jun 2016 21:04:06 GMT",
"version": "v1"
},
{
"created": "Sun, 10 Jul 2016 03:12:18 GMT",
"version": "v2"
},
{
"created": "Tue, 19 Jul 2016 19:41:45 GMT",
"version": "v3"
},
{
"created": "Tue, 13 Dec 2016 12:46:29 GMT",
"version": "v4"
},
{
"created": "Sun, 8 Jan 2017 22:47:01 GMT",
"version": "v5"
},
{
"created": "Wed, 31 May 2017 16:27:37 GMT",
"version": "v6"
},
{
"created": "Wed, 14 Jun 2017 19:46:35 GMT",
"version": "v7"
}
] | 2018-06-05 | [
[
"Adler",
"Stephen L.",
""
]
] | We continue our study of Coleman-Weinberg symmetry breaking induced by a third rank antisymmetric tensor scalar, in the context of the $SU(8)$ model we proposed earlier. We focus in this paper on qualitative features that will determine whether the model can make contact with the observed particle spectrum. We discuss the mechanism for giving the spin $\frac{3}{2}$ field a mass by the BEH mechanism, and analyze the remaining massless spin $\frac{1}{2}$ fermions, the global chiral symmetries, and the running couplings after symmetry breaking. We note that the smallest gluon mass matrix eigenvalue has an eigenvector suggestive of $U(1)_{B-L}$, and conjecture that the theory runs to an infrared fixed point at which there is a massless gluon with 3 to -1 ratios in generator components. Assuming this, we discuss a mechanism for making contact with the standard model, based on a conjectured asymmetric breaking of $Sp(4)$ to $SU(2)$ subgroups, one of which is the electroweak $SU(2)$, and the other of which is a "technicolor" group that binds the original $SU(8)$ model fermions, which play the role of "preons", into composites. Quarks can emerge as 5 preon composites and leptons as 3 preon composites, with consequent stability of the proton against decay to a single lepton plus a meson. A composite Higgs boson can emerge as a two preon composite. Since anomaly matching for the relevant conserved global symmetry current is not obeyed by three fermion families, emergence of three composite families requires formation of a Goldstone boson with quantum numbers matching this current, which can be a light dark matter candidate. |
1103.4437 | Poulose Poulose Dr. | S. Hesselbach, S. Moretti, S. Munir, P. Poulose | CP-violating Higgs sector of the MSSM through gluon.gluon --> H1 -->
gamma.gamma | 4 pages, 3 figures, presented at DISCRETE 2010, Rome, 6-11 December
2010 | null | 10.1088/1742-6596/335/1/012020 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the effect of explicit CP violation in the Higgs sectors of the MSSM
in the di-photon decay of the lightest CP-mixed Higgs state. Further it is
shown that the gluon fusion production mechanism along with the di-photon decay
enhances CP-violating effects for a large set of suitably chosen parameter
values.
| [
{
"created": "Wed, 23 Mar 2011 05:03:45 GMT",
"version": "v1"
}
] | 2015-05-27 | [
[
"Hesselbach",
"S.",
""
],
[
"Moretti",
"S.",
""
],
[
"Munir",
"S.",
""
],
[
"Poulose",
"P.",
""
]
] | We study the effect of explicit CP violation in the Higgs sectors of the MSSM in the di-photon decay of the lightest CP-mixed Higgs state. Further it is shown that the gluon fusion production mechanism along with the di-photon decay enhances CP-violating effects for a large set of suitably chosen parameter values. |
2405.15387 | Shu-Min Zhao | Xing-Yu Han, Jiao Ma, Long Ruan, Xi Wang, Xing-Xing Dong, Shu-Min Zhao | Study some two loop contribution to muon MDM in the N-B-LSSM | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is well known that the muon magnetic dipole moment (MDM) has close
relation with the new physics (NP) in the development of the Standard Model
(SM). Combined with the Fermilab National Accelerator Laboratory (FNAL) and the
Brookhaven National Laboratory (BNL) E821 result, the departure from the SM
prediction is about 5.0 $\sigma$. We study the electroweak corrections from
several type two-loop SUSY diagrams and the virtual SUSY particles include
chargino, neutralino, scalar lepton and scalar neutrino. Based on the latest
experimental constraints, we study the muon MDM under the next to the minimal
supersymmetric extension of the SM with local B-L gauge symmetry (N-B-LSSM).
The abundant numerical results verify that
$\tan{\beta},~T_e,~M^2_L,~M^2_e,~M_{BB'}$ and $M^2_{eij}$ play an important
role in muon MDM. $M^2_e,~\tan{\beta}$ and $T_e$ are sensitive parameters to
muon MDM. From the data obtained in all the figures of the numerical results,
most of the values of $a_{\mu}^{NBL}$ are in 2$\sigma$ interval, which can
compensate the departure between the experiment data and the SM prediction.
| [
{
"created": "Fri, 24 May 2024 09:36:58 GMT",
"version": "v1"
},
{
"created": "Sat, 29 Jun 2024 13:05:07 GMT",
"version": "v2"
}
] | 2024-07-02 | [
[
"Han",
"Xing-Yu",
""
],
[
"Ma",
"Jiao",
""
],
[
"Ruan",
"Long",
""
],
[
"Wang",
"Xi",
""
],
[
"Dong",
"Xing-Xing",
""
],
[
"Zhao",
"Shu-Min",
""
]
] | It is well known that the muon magnetic dipole moment (MDM) has close relation with the new physics (NP) in the development of the Standard Model (SM). Combined with the Fermilab National Accelerator Laboratory (FNAL) and the Brookhaven National Laboratory (BNL) E821 result, the departure from the SM prediction is about 5.0 $\sigma$. We study the electroweak corrections from several type two-loop SUSY diagrams and the virtual SUSY particles include chargino, neutralino, scalar lepton and scalar neutrino. Based on the latest experimental constraints, we study the muon MDM under the next to the minimal supersymmetric extension of the SM with local B-L gauge symmetry (N-B-LSSM). The abundant numerical results verify that $\tan{\beta},~T_e,~M^2_L,~M^2_e,~M_{BB'}$ and $M^2_{eij}$ play an important role in muon MDM. $M^2_e,~\tan{\beta}$ and $T_e$ are sensitive parameters to muon MDM. From the data obtained in all the figures of the numerical results, most of the values of $a_{\mu}^{NBL}$ are in 2$\sigma$ interval, which can compensate the departure between the experiment data and the SM prediction. |
2103.13896 | Rohit Gupta | Rohit Gupta and Satyajit Jena | A unified formalism to study $soft$ as well as $hard$ part of the
transverse momentum spectra | presented at DAE-BRNS HEP Symposium Dec 2020, NISER, Jatni, Odisha,
India | null | null | null | hep-ph | http://creativecommons.org/licenses/by-nc-nd/4.0/ | Transverse momentum $p_T$ spectra of final state particles produced in high
energy heavy-ion collision can be divided into two distinct regions based on
the difference in the underlying particle production process. We have provided
a unified formalism to explain both low- and high-$p_T$ regime of spectra in a
consistent manner. The $p_T$ spectra of final state particles produced at RHIC
and LHC energies have been analysed using unified formalism to test its
applicability at different energies, and a good agreement with the data is
obtained across all energies. Further, the prospect of extracting the elliptic
flow coefficient directly from the transverse momentum spectra is explored.
| [
{
"created": "Thu, 25 Mar 2021 15:02:54 GMT",
"version": "v1"
}
] | 2021-03-26 | [
[
"Gupta",
"Rohit",
""
],
[
"Jena",
"Satyajit",
""
]
] | Transverse momentum $p_T$ spectra of final state particles produced in high energy heavy-ion collision can be divided into two distinct regions based on the difference in the underlying particle production process. We have provided a unified formalism to explain both low- and high-$p_T$ regime of spectra in a consistent manner. The $p_T$ spectra of final state particles produced at RHIC and LHC energies have been analysed using unified formalism to test its applicability at different energies, and a good agreement with the data is obtained across all energies. Further, the prospect of extracting the elliptic flow coefficient directly from the transverse momentum spectra is explored. |
1310.3029 | Shunsuke Ohkoda | Shunsuke Ohkoda, Shigehiro Yasui, Atsushi Hosaka | Decays of Zb -> Upsilon + pi via triangle diagrams in heavy meson
molecules | 10 pages, 5 figures | Phys. Rev. D 89, 074029 (2014) | 10.1103/PhysRevD.89.074029 | KEK-TH-1677, J-PARC-TH-30 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Bottomonium-like resonances Zb(10610) and Zb'(10650) are good candidates of
hadronic molecules composed of BBbar* (or B*Bbar) and B*Bbar*, respectively.
Considering Zb (Zb') as heavy meson molecules, we investigate the decays of
Zb(')^+ -> Upsilon (nS) pi^+$ in terms of the heavy meson effective theory. We
find that the intermediate B (B*) and Bbar (Bbar*) meson loops and the form
factors play a significant role to reproduce the experimental values of the
decay widths. We also predict the decay widths of Zc^+ -> J/\psi pi^+ and
psi(2S) pi^+ for a charmonium-like resonance Zc which has been reported
recently in experiments.
| [
{
"created": "Fri, 11 Oct 2013 06:35:36 GMT",
"version": "v1"
}
] | 2014-04-23 | [
[
"Ohkoda",
"Shunsuke",
""
],
[
"Yasui",
"Shigehiro",
""
],
[
"Hosaka",
"Atsushi",
""
]
] | Bottomonium-like resonances Zb(10610) and Zb'(10650) are good candidates of hadronic molecules composed of BBbar* (or B*Bbar) and B*Bbar*, respectively. Considering Zb (Zb') as heavy meson molecules, we investigate the decays of Zb(')^+ -> Upsilon (nS) pi^+$ in terms of the heavy meson effective theory. We find that the intermediate B (B*) and Bbar (Bbar*) meson loops and the form factors play a significant role to reproduce the experimental values of the decay widths. We also predict the decay widths of Zc^+ -> J/\psi pi^+ and psi(2S) pi^+ for a charmonium-like resonance Zc which has been reported recently in experiments. |
1307.5682 | Sreemoyee Sarkar | S. Sarkar, K. Pal and A. K. Dutt-Mazumder | Role of Magnetic Interaction in Dense Plasma | null | Advances in High Energy Physics, 530895 (2013) | null | null | hep-ph astro-ph.HE nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Quasiparticle excitations and associated phenomena of energy and momentum
transfer rates have been calculated in terms of the drag and the diffusion
coefficients exposing clearly the dominance of the magnetic interaction over
its electric counterpart. The results have been compared with the finite
temperature results highlighting the similarities and dissimilarities in the
two extreme regimes of temperature and density. Non-Fermi-liquid behavior of
various physical quantities like neutrino mean free path and thermal relaxation
time due to the inclusion of magnetic interaction has clearly been revealed.
All the results presented in the current review are pertinent to the degenerate
and ultradegenerate plasma.
| [
{
"created": "Mon, 22 Jul 2013 12:32:30 GMT",
"version": "v1"
}
] | 2013-07-23 | [
[
"Sarkar",
"S.",
""
],
[
"Pal",
"K.",
""
],
[
"Dutt-Mazumder",
"A. K.",
""
]
] | Quasiparticle excitations and associated phenomena of energy and momentum transfer rates have been calculated in terms of the drag and the diffusion coefficients exposing clearly the dominance of the magnetic interaction over its electric counterpart. The results have been compared with the finite temperature results highlighting the similarities and dissimilarities in the two extreme regimes of temperature and density. Non-Fermi-liquid behavior of various physical quantities like neutrino mean free path and thermal relaxation time due to the inclusion of magnetic interaction has clearly been revealed. All the results presented in the current review are pertinent to the degenerate and ultradegenerate plasma. |
1208.0375 | Takahiro Sasaki | Takahiro Sasaki, Hiroaki Kouno, Masanobu Yahiro | A practical solution to the sign problem at finite theta-vacuum angle | 5 pages, 6 figures | null | 10.1103/PhysRevD.87.056003 | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a practical way of circumventing the sign problem in lattice QCD
simulations with a theta-vacuum term. This method is the reweighting method for
the QCD Lagrangian after the U_A(1) transformation. In the Lagrangian, the
P-odd mass term as a cause of the sign problem is minimized. In order to find
out a good reference system in the reweighting method, we estimate the average
reweighting factor by using the two-flavor NJL model and eventually find a good
reference system.
| [
{
"created": "Wed, 1 Aug 2012 23:25:11 GMT",
"version": "v1"
}
] | 2013-03-14 | [
[
"Sasaki",
"Takahiro",
""
],
[
"Kouno",
"Hiroaki",
""
],
[
"Yahiro",
"Masanobu",
""
]
] | We propose a practical way of circumventing the sign problem in lattice QCD simulations with a theta-vacuum term. This method is the reweighting method for the QCD Lagrangian after the U_A(1) transformation. In the Lagrangian, the P-odd mass term as a cause of the sign problem is minimized. In order to find out a good reference system in the reweighting method, we estimate the average reweighting factor by using the two-flavor NJL model and eventually find a good reference system. |
hep-ph/0406185 | Krzysztof Urbanowski | K. Urbanowski | On the scalar product of short and long living states of neutral kaons
in the CPT invariant system | LaTeX2e, 21 pages, new comments nad references added | Acta Phys.Polon.B37:1727-1744,2006 | null | null | hep-ph hep-ex | null | This paper contains a detailed analysis of the properties of the scalar
product of short and long living superpositions of neutral $|K_{0}>$,
$|{\bar{K}}_{0}>$ mesons. It is shown for the exact effective Hamiltonian for
neutral meson subsystem that the scalar product of its eigenvectors, which
correspond with these short and long living superpositions, can not be real
with the assumption of CPT conserved and CP violated. The standard conclusion
obtained within the Lee-Oehme-Yang theory of neutral kaons is that in this case
such a product should be real.
| [
{
"created": "Thu, 17 Jun 2004 06:51:32 GMT",
"version": "v1"
},
{
"created": "Sun, 27 Jun 2004 15:16:47 GMT",
"version": "v2"
},
{
"created": "Fri, 28 Jan 2005 16:18:14 GMT",
"version": "v3"
},
{
"created": "Fri, 30 Sep 2005 11:16:49 GMT",
"version": "v4"
}
] | 2016-09-06 | [
[
"Urbanowski",
"K.",
""
]
] | This paper contains a detailed analysis of the properties of the scalar product of short and long living superpositions of neutral $|K_{0}>$, $|{\bar{K}}_{0}>$ mesons. It is shown for the exact effective Hamiltonian for neutral meson subsystem that the scalar product of its eigenvectors, which correspond with these short and long living superpositions, can not be real with the assumption of CPT conserved and CP violated. The standard conclusion obtained within the Lee-Oehme-Yang theory of neutral kaons is that in this case such a product should be real. |
2207.10912 | Xiaohu Sun | Botao Guo, Xiaohu Sun, Licheng Zhang, Zhe Li, Yong Ban | Search for the Higgs boson pair production in the $b\bar{b}\mu^+\mu^-$
final state at the LHC | null | null | 10.1103/PhysRevD.107.034014 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Higgs boson pair production via gluon-gluon fusion and vector boson
fusion in the $b\bar{b}\mu^+\mu^-$ final state at the LHC is studied to probe
the Higgs self-coupling $\kappa_\lambda$ and the four-boson HHVV coupling
$\kappa_{\rm{2V}}$ for the first time. A cut-based analysis and a machine
learning analysis using boosted decision trees are performed with
categorizations and optimizations depending on the variations of these
couplings. The expected sensitivities are extracted with different integrated
luminosities assumed up to the full HL-LHC runs. The expected upper limit at
95\% confidence level on the HH production is calculated as 47 (28) times the
Standard Model cross-section using the cut-based method (boosted decision
trees) for the gluon-gluon fusion production, and 928 for the vector boson
fusion production, assuming an integrated luminosity of 3000 fb$^{-1}$. The
expected constraints on the couplings at 95\% confidence level are calculated
to be $-13.8< \kappa_{\lambda}< 19.1$ ($-10.0< \kappa_{\lambda}< 15.5$) and
$-3.4< \kappa_{\rm{2V}}< 5.5$ using the cut-based method (boosted decision
trees), respectively, assuming an integrated luminosity of 3000 fb$^{-1}$.
| [
{
"created": "Fri, 22 Jul 2022 07:11:45 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Aug 2022 13:36:42 GMT",
"version": "v2"
},
{
"created": "Fri, 2 Dec 2022 13:13:12 GMT",
"version": "v3"
}
] | 2023-03-08 | [
[
"Guo",
"Botao",
""
],
[
"Sun",
"Xiaohu",
""
],
[
"Zhang",
"Licheng",
""
],
[
"Li",
"Zhe",
""
],
[
"Ban",
"Yong",
""
]
] | The Higgs boson pair production via gluon-gluon fusion and vector boson fusion in the $b\bar{b}\mu^+\mu^-$ final state at the LHC is studied to probe the Higgs self-coupling $\kappa_\lambda$ and the four-boson HHVV coupling $\kappa_{\rm{2V}}$ for the first time. A cut-based analysis and a machine learning analysis using boosted decision trees are performed with categorizations and optimizations depending on the variations of these couplings. The expected sensitivities are extracted with different integrated luminosities assumed up to the full HL-LHC runs. The expected upper limit at 95\% confidence level on the HH production is calculated as 47 (28) times the Standard Model cross-section using the cut-based method (boosted decision trees) for the gluon-gluon fusion production, and 928 for the vector boson fusion production, assuming an integrated luminosity of 3000 fb$^{-1}$. The expected constraints on the couplings at 95\% confidence level are calculated to be $-13.8< \kappa_{\lambda}< 19.1$ ($-10.0< \kappa_{\lambda}< 15.5$) and $-3.4< \kappa_{\rm{2V}}< 5.5$ using the cut-based method (boosted decision trees), respectively, assuming an integrated luminosity of 3000 fb$^{-1}$. |
hep-ph/0111300 | Arnd Leike | A. Leike | Why extra gauge Bosons should exist and how to hunt them | 3 pagex LaTex, talk presented at the symposium ``100 Years Werner
Heisenberg -- Works and Impact'', Bamberg, Germany, September 2001 | Fortsch.Phys. 50 (2002) 538-540 | 10.1002/1521-3978(200205)50:5/7<538::AID-PROP538>3.0.CO;2-7 | LMU-16/01 | hep-ph | null | Werner Heisenberg's work is the foundation for many topics of present
research. This is also true for the search for extra gauge bosons. The
prospects of future colliders in this search are shortly mentioned.
| [
{
"created": "Fri, 23 Nov 2001 09:41:34 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Leike",
"A.",
""
]
] | Werner Heisenberg's work is the foundation for many topics of present research. This is also true for the search for extra gauge bosons. The prospects of future colliders in this search are shortly mentioned. |
2305.12225 | Jason Baretz | Jason Baretz and Nicholas Carrara and Jacob Hollingsworth and Daniel
Whiteson | Visualization and Efficient Generation of Constrained High-dimensional
Theoretical Parameter Spaces | Expanded on motivation for methods, added additional metrics and
further discussion/comparison of methods | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We describe a set of novel methods for efficiently sampling high-dimensional
parameter spaces of physical theories defined at high energies, but constrained
by experimental measurements made at lower energies. Often, theoretical models
such as supersymmetry are defined by many parameters, $\mathcal{O}(10-100)$,
expressed at high energies, while relevant experimental constraints are often
defined at much lower energies, preventing them from directly ruling out
portions of the space. Instead, the low-energy constraints define a complex,
potentially non-contiguous subspace of the theory parameters. Naive scanning of
the theory space for points which satisfy the low-energy constraints is
hopelessly inefficient due to the high dimensionality, and the inverse problem
is considered intractable. As a result, many theoretical spaces remain
under-explored. We introduce a class of modified generative autoencoders, which
attack this problem by mapping the high-dimensional parameter space to a
structured low-dimensional latent space, allowing for easy visualization and
efficient generation of theory points which satisfy experimental constraints.
An extension without dimensional compression, which focuses on limiting
potential information loss, is also introduced.
| [
{
"created": "Sat, 20 May 2023 16:25:08 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Oct 2023 14:18:38 GMT",
"version": "v2"
}
] | 2023-10-04 | [
[
"Baretz",
"Jason",
""
],
[
"Carrara",
"Nicholas",
""
],
[
"Hollingsworth",
"Jacob",
""
],
[
"Whiteson",
"Daniel",
""
]
] | We describe a set of novel methods for efficiently sampling high-dimensional parameter spaces of physical theories defined at high energies, but constrained by experimental measurements made at lower energies. Often, theoretical models such as supersymmetry are defined by many parameters, $\mathcal{O}(10-100)$, expressed at high energies, while relevant experimental constraints are often defined at much lower energies, preventing them from directly ruling out portions of the space. Instead, the low-energy constraints define a complex, potentially non-contiguous subspace of the theory parameters. Naive scanning of the theory space for points which satisfy the low-energy constraints is hopelessly inefficient due to the high dimensionality, and the inverse problem is considered intractable. As a result, many theoretical spaces remain under-explored. We introduce a class of modified generative autoencoders, which attack this problem by mapping the high-dimensional parameter space to a structured low-dimensional latent space, allowing for easy visualization and efficient generation of theory points which satisfy experimental constraints. An extension without dimensional compression, which focuses on limiting potential information loss, is also introduced. |
hep-ph/9604334 | Ed Stoeffhaas | V. Barger, M.S. Berger, J.F. Gunion, and T. Han | Particle Physics Opportunities at $\mu^+\mu^-$ Colliders | 19 pages, Latex, uses psfig.tex to place 16 postscript figures. Based
on talks given at the Symposium on Physics Potential and Development of
$\mu^+\mu^-$ Colliders, San Francisco, California, December 13-15, 1995.
Compressed postscript version of paper with figures available at
http://phenom.physics.wisc.edu/pub/preprints/1996/madph-96-939.ps.Z or at
ftp://phenom.physics.wisc.edu/pub/preprints/1996/madph-96-939.ps.Z | Nucl.Phys.Proc.Suppl.51A:13-31,1996 | null | MADPH-96-939, UCD-96-12 | hep-ph hep-ex | null | We discuss the capabilities of future muon colliders to resolve important
particle physics questions. A collider with c.m. energy $\sqrt s = 100$ to
500~GeV offers the unique opportunity to produce Higgs bosons in the
$s$-channel and thereby measure the Higgs masses, total widths and several
partial widths to high precision. At this same machine, $t\bar t$ and $W^+W^-$
threshold studies would yield superior precision in the determination of $m_t$
and $m_W$. A multi-TeV $\mu^+\mu^-$ collider would open up the realm of physics
above the 1 TeV scale, allowing, for example, copious production of
supersymmetric particles up to the highest anticipated masses or a detailed
study of the strongly-interacting scenario of electroweak symmetry breaking.
| [
{
"created": "Tue, 16 Apr 1996 17:12:42 GMT",
"version": "v1"
}
] | 2009-09-15 | [
[
"Barger",
"V.",
""
],
[
"Berger",
"M. S.",
""
],
[
"Gunion",
"J. F.",
""
],
[
"Han",
"T.",
""
]
] | We discuss the capabilities of future muon colliders to resolve important particle physics questions. A collider with c.m. energy $\sqrt s = 100$ to 500~GeV offers the unique opportunity to produce Higgs bosons in the $s$-channel and thereby measure the Higgs masses, total widths and several partial widths to high precision. At this same machine, $t\bar t$ and $W^+W^-$ threshold studies would yield superior precision in the determination of $m_t$ and $m_W$. A multi-TeV $\mu^+\mu^-$ collider would open up the realm of physics above the 1 TeV scale, allowing, for example, copious production of supersymmetric particles up to the highest anticipated masses or a detailed study of the strongly-interacting scenario of electroweak symmetry breaking. |
hep-ph/0410346 | Giovannangeli | P. Giovannangeli | Two loop renormalisation of the magnetic coupling in hot QCD and spatial
Wilson loop | 5 pages. To appear in the proceedings of 6th Conference on Strong and
Electroweak Matter 2004 (SEWM04), Helsinki, Finland, 16-19 Jun 2004 | null | 10.1142/9789812702159_0033 | null | hep-ph hep-lat | null | With the known two loop renormalisation of the magnetic coupling, the 4D
results of the spatial Wilson loop are compared to the prediction from the
magnetostatic sector.
| [
{
"created": "Tue, 26 Oct 2004 16:33:40 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Giovannangeli",
"P.",
""
]
] | With the known two loop renormalisation of the magnetic coupling, the 4D results of the spatial Wilson loop are compared to the prediction from the magnetostatic sector. |
2204.04202 | Yang Zhang | Jin Min Yang, Yang Zhang | Low energy SUSY confronted with new measurements of W-boson mass and
muon g-2 | 8 pages, 4 figures, 3 tabels, published in Science Bulletin | Science Bulletin, 2022 | 10.1016/j.scib.2022.06.007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The new CDF II measurement of $W$-boson mass shows a 7$\sigma$ deviation from
the Standard Model (SM) prediction, while the recent FNAL measurement of the
muon $g-2$ shows a 4.2$\sigma$ deviation (combined with the BNL result) from
the SM. Both of them strongly indicate new physics beyond the SM. In this work
we study the implication of both measurements on low energy supersymmetry. With
an extensive exploration of the parameter space of the minimal supersymmetric
standard model (MSSM), we find that in the parameter space allowed by current
experimental constraints from colliders and dark matter detections, the MSSM
can simultaneously explain both measurements on the edge of $2\sigma$ level,
taking theoretical uncertainties into consideration. The favored parameter
space, characterized by a compressed spectrum between bino, wino and stau, with
the stop being around 1 TeV, may be covered in the near future LHC searches.
| [
{
"created": "Fri, 8 Apr 2022 17:56:23 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Apr 2022 15:17:51 GMT",
"version": "v2"
},
{
"created": "Mon, 13 Jun 2022 03:08:55 GMT",
"version": "v3"
}
] | 2022-06-14 | [
[
"Yang",
"Jin Min",
""
],
[
"Zhang",
"Yang",
""
]
] | The new CDF II measurement of $W$-boson mass shows a 7$\sigma$ deviation from the Standard Model (SM) prediction, while the recent FNAL measurement of the muon $g-2$ shows a 4.2$\sigma$ deviation (combined with the BNL result) from the SM. Both of them strongly indicate new physics beyond the SM. In this work we study the implication of both measurements on low energy supersymmetry. With an extensive exploration of the parameter space of the minimal supersymmetric standard model (MSSM), we find that in the parameter space allowed by current experimental constraints from colliders and dark matter detections, the MSSM can simultaneously explain both measurements on the edge of $2\sigma$ level, taking theoretical uncertainties into consideration. The favored parameter space, characterized by a compressed spectrum between bino, wino and stau, with the stop being around 1 TeV, may be covered in the near future LHC searches. |
1108.4278 | Martin Spinrath | Stefan Antusch, Stephen F. King, Christoph Luhn, Martin Spinrath | Trimaximal mixing with predicted \theta_13 from a new type of
constrained sequential dominance | 13 pages, 2 figures; version to appear in Nuclear Physics B | null | 10.1016/j.nuclphysb.2011.11.009 | MPP-2011-101; SHEP-11-23; SISSA 44/2011/EP | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Following the recent T2K indication of a sizeable reactor angle, we present a
class of models which fix \theta_{13} while preserving trimaximal solar mixing.
The models are based on a new type of constrained sequential dominance
involving new vacuum alignments, along the (1,2,0)^T or (1,0,2)^T directions in
flavour space. We show that such alignments are easily achieved using
orthogonality, and may replace the role of the subdominant flavon alignment
(1,1,1)^T in constrained sequential dominance. In such models, with a normal
hierarchical spectrum, the reactor angle is related to a ratio of neutrino
masses by \theta_{13} = \frac{\sqrt{2}}{3}\frac{m^\nu_2}{m^\nu_3}, leading to
\theta_{13} \sim 5^\circ - 6^\circ, while the atmospheric angle is given by the
sum rule \theta_{23} \approx 45^\circ + \sqrt{2} \theta_{13} \cos \delta. We
find that leptogenesis is unsuppressed due to the violation of form dominance
and that the CP violating phase responsible for leptogenesis is precisely equal
to the Dirac CP phase \delta, providing a direct link between leptogenesis and
neutrino mixing in this class of models.
| [
{
"created": "Mon, 22 Aug 2011 11:23:06 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Aug 2011 08:33:24 GMT",
"version": "v2"
},
{
"created": "Mon, 14 Nov 2011 11:51:01 GMT",
"version": "v3"
}
] | 2011-11-15 | [
[
"Antusch",
"Stefan",
""
],
[
"King",
"Stephen F.",
""
],
[
"Luhn",
"Christoph",
""
],
[
"Spinrath",
"Martin",
""
]
] | Following the recent T2K indication of a sizeable reactor angle, we present a class of models which fix \theta_{13} while preserving trimaximal solar mixing. The models are based on a new type of constrained sequential dominance involving new vacuum alignments, along the (1,2,0)^T or (1,0,2)^T directions in flavour space. We show that such alignments are easily achieved using orthogonality, and may replace the role of the subdominant flavon alignment (1,1,1)^T in constrained sequential dominance. In such models, with a normal hierarchical spectrum, the reactor angle is related to a ratio of neutrino masses by \theta_{13} = \frac{\sqrt{2}}{3}\frac{m^\nu_2}{m^\nu_3}, leading to \theta_{13} \sim 5^\circ - 6^\circ, while the atmospheric angle is given by the sum rule \theta_{23} \approx 45^\circ + \sqrt{2} \theta_{13} \cos \delta. We find that leptogenesis is unsuppressed due to the violation of form dominance and that the CP violating phase responsible for leptogenesis is precisely equal to the Dirac CP phase \delta, providing a direct link between leptogenesis and neutrino mixing in this class of models. |
0907.3709 | Alexander Andrianov A | Alexander A. Andrianov, Domenec Espriu, Paola Giacconi and Roberto
Soldati | Anomalous positron excess from Lorentz-violating QED | 13 pages, few refs and comments on electron radiation added | JHEP 0909:057,2009 | 10.1088/1126-6708/2009/09/057 | UB-ECM-PF-09/19, ICCUB-09-218 | hep-ph astro-ph.HE gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We entertain the idea that a suitable background of cold (very low momentum)
pseudoscalar particles or condensate, may trigger a background that effectively
generates Lorentz-invariance violation. This aether-like background induces a
Chern-Simons modification of QED. Physics is different in different frames and,
in the rest frame of the pseudoscalar background, high momentum photons can
decay into pairs. The threshold for such decay depends quadratically on the
rest mass of the particles. This mechanism could explain in a natural way why
antiprotons are absent in recent cosmic ray measurements. A similar signal
could be used as a probe of pseudoscalar condensation in heavy ion collisions.
| [
{
"created": "Tue, 21 Jul 2009 17:29:29 GMT",
"version": "v1"
},
{
"created": "Sat, 5 Sep 2009 05:06:30 GMT",
"version": "v2"
}
] | 2009-12-10 | [
[
"Andrianov",
"Alexander A.",
""
],
[
"Espriu",
"Domenec",
""
],
[
"Giacconi",
"Paola",
""
],
[
"Soldati",
"Roberto",
""
]
] | We entertain the idea that a suitable background of cold (very low momentum) pseudoscalar particles or condensate, may trigger a background that effectively generates Lorentz-invariance violation. This aether-like background induces a Chern-Simons modification of QED. Physics is different in different frames and, in the rest frame of the pseudoscalar background, high momentum photons can decay into pairs. The threshold for such decay depends quadratically on the rest mass of the particles. This mechanism could explain in a natural way why antiprotons are absent in recent cosmic ray measurements. A similar signal could be used as a probe of pseudoscalar condensation in heavy ion collisions. |
2202.02165 | Xuhui Jiang | Xu-Hui Jiang, Aurelio Juste, Ying-Ying Li, Tao Liu | Detecting New Physics as Novelty -- Complementarity Matters | 32 pages, 20 figures | JHEP 10 (2022) 085 | 10.1007/JHEP10(2022)085 | FERMILAB-PUB-22-035-T | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Novelty detection is a task of machine learning that aims at detecting novel
events without a prior knowledge. In particular, its techniques can be applied
to detect unexpected signals from new phenomena at colliders. In this paper, we
develop an analysis scheme that exploits the complementarity, originally
studied in Ref.~\cite{Hajer:2018kqm}, between isolation-based and
clustering-based novelty evaluators. This approach can significantly improve
the performance and overall applicability of novelty detection at colliders,
which we demonstrate using a variety of two dimensional Gaussian samples
mimicking collider events. As a further proof of principle, we subsequently
apply this scheme to the detection of two significantly different signals at
the LHC featuring a $t\bar{t}\gamma\gamma$ final state: $t\bar t h$, giving a
narrow resonance in the diphoton mass spectrum, and gravity-mediated
supersymmetry, which results in broad distributions at high transverse
momentum. Compared to existing dedicated searches at the LHC, the sensitivities
for both signals are found to be encouraging.
| [
{
"created": "Fri, 4 Feb 2022 14:46:55 GMT",
"version": "v1"
},
{
"created": "Sat, 10 Dec 2022 07:11:16 GMT",
"version": "v2"
}
] | 2022-12-13 | [
[
"Jiang",
"Xu-Hui",
""
],
[
"Juste",
"Aurelio",
""
],
[
"Li",
"Ying-Ying",
""
],
[
"Liu",
"Tao",
""
]
] | Novelty detection is a task of machine learning that aims at detecting novel events without a prior knowledge. In particular, its techniques can be applied to detect unexpected signals from new phenomena at colliders. In this paper, we develop an analysis scheme that exploits the complementarity, originally studied in Ref.~\cite{Hajer:2018kqm}, between isolation-based and clustering-based novelty evaluators. This approach can significantly improve the performance and overall applicability of novelty detection at colliders, which we demonstrate using a variety of two dimensional Gaussian samples mimicking collider events. As a further proof of principle, we subsequently apply this scheme to the detection of two significantly different signals at the LHC featuring a $t\bar{t}\gamma\gamma$ final state: $t\bar t h$, giving a narrow resonance in the diphoton mass spectrum, and gravity-mediated supersymmetry, which results in broad distributions at high transverse momentum. Compared to existing dedicated searches at the LHC, the sensitivities for both signals are found to be encouraging. |
2212.03541 | Jia-Jie Jiang | Jia-Jie Jiang, Ya-Zhao Xiao, Jiajia Qin, Xiaohua Li, Xun Chen | Three-quark potential at finite temperature and chemical potential | null | null | 10.1088/1674-1137/ac9894 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using gauge/gravity duality, we study the potential energy and the melting of
triply heavy baryon at finite temperature and chemical potential in this paper.
First, we calculate three-quark potential and compare the results with
quark-antiquark potential. With the increase of temperature and chemical
potential, the potential energy will decrease at large distances. It is found
that the three-quark potential will have an endpoint at high temperature and/or
large chemical potential, which means triply heavy baryons will melt at enough
high temperature and/or large chemical potential. We also discuss screening
distance which can be extracted from the three-quark potential. At last, we
draw the melting diagram of triply heavy baryons in the $T-\mu$ plane.
| [
{
"created": "Wed, 7 Dec 2022 09:44:15 GMT",
"version": "v1"
}
] | 2022-12-21 | [
[
"Jiang",
"Jia-Jie",
""
],
[
"Xiao",
"Ya-Zhao",
""
],
[
"Qin",
"Jiajia",
""
],
[
"Li",
"Xiaohua",
""
],
[
"Chen",
"Xun",
""
]
] | Using gauge/gravity duality, we study the potential energy and the melting of triply heavy baryon at finite temperature and chemical potential in this paper. First, we calculate three-quark potential and compare the results with quark-antiquark potential. With the increase of temperature and chemical potential, the potential energy will decrease at large distances. It is found that the three-quark potential will have an endpoint at high temperature and/or large chemical potential, which means triply heavy baryons will melt at enough high temperature and/or large chemical potential. We also discuss screening distance which can be extracted from the three-quark potential. At last, we draw the melting diagram of triply heavy baryons in the $T-\mu$ plane. |
1110.0762 | Semikoz Dmitry | Ram Brustein, Dmitri Semikoz | Apparent superluminal neutrino propagation caused by nonlinear coherent
interactions in matter | 7 pages | null | 10.1016/j.physletb.2011.11.039 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Quantum coherence can significantly increase the strength of the forward
scattering of neutrinos propagating through the Earth and interacting with
matter. The index of refraction of the neutrinos propagating in a medium and
hence their phase velocity is determined by the forward scattering. So,
depending on the nature of the interaction of neutrinos with matter, their
phase velocity can be larger than the speed of light in vacuum. We show that
such effects can explain the apparent superluminal propagation of muon
neutrinos found recently by the OPERA experiment. Our proposal explains why the
neutrino oscillations and the propagation of neutrinos from supernova 1987A are
unaffected. It can be verified by changing the amount of neutrino coherence or
by changing the composition of matter in which they propagate.
| [
{
"created": "Tue, 4 Oct 2011 17:32:27 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Brustein",
"Ram",
""
],
[
"Semikoz",
"Dmitri",
""
]
] | Quantum coherence can significantly increase the strength of the forward scattering of neutrinos propagating through the Earth and interacting with matter. The index of refraction of the neutrinos propagating in a medium and hence their phase velocity is determined by the forward scattering. So, depending on the nature of the interaction of neutrinos with matter, their phase velocity can be larger than the speed of light in vacuum. We show that such effects can explain the apparent superluminal propagation of muon neutrinos found recently by the OPERA experiment. Our proposal explains why the neutrino oscillations and the propagation of neutrinos from supernova 1987A are unaffected. It can be verified by changing the amount of neutrino coherence or by changing the composition of matter in which they propagate. |
hep-ph/0111413 | Ismd31 | Thomas Nunnemann (for the DO and CDF Collaborations) | Measurements of Higher Order Effects in QCD from the Tevatron Collider | 4 pages, 3 figures in epsi file, talk given at XXXI International
Symposium on Multiparticle Dynamics, Sept 1-7, 2001, Datong China. URL
http://ismd31.ccnu.edu.cn/ | null | 10.1142/9789812778048_0040 | null | hep-ph | null | Quantum Chromodynamics has been studied extensively at Fermilab's Tevatron
collider. Between 1992 and 1996 the D{\O}and CDF experiments, each accumulated
approximately $100 \mathrm{pb}^{-1}$ of proton-antiproton collisions at a
center-of-mass energy $\sqrt{s}=1800 \mathrm{GeV}$ and $\sim 0.5
\mathrm{pb}^{-1}$ at $\sqrt{s}=630 \mathrm{GeV}$. In this paper, we present
selected recent measurements of higher order effects in QCD: multiple jet
production and subjet and charged particle multiplicities in quark and gluon
jets.
| [
{
"created": "Thu, 29 Nov 2001 13:04:32 GMT",
"version": "v1"
}
] | 2019-08-14 | [
[
"Nunnemann",
"Thomas",
"",
"for the DO and CDF Collaborations"
]
] | Quantum Chromodynamics has been studied extensively at Fermilab's Tevatron collider. Between 1992 and 1996 the D{\O}and CDF experiments, each accumulated approximately $100 \mathrm{pb}^{-1}$ of proton-antiproton collisions at a center-of-mass energy $\sqrt{s}=1800 \mathrm{GeV}$ and $\sim 0.5 \mathrm{pb}^{-1}$ at $\sqrt{s}=630 \mathrm{GeV}$. In this paper, we present selected recent measurements of higher order effects in QCD: multiple jet production and subjet and charged particle multiplicities in quark and gluon jets. |
1501.06505 | Francesca Aceti | F. Aceti, J. M. Dias and E. Oset | $f_1(1285)$ decays into $a_0(980)\pi^0$, $f_0(980)\pi^0$ and isospin
breaking | null | null | 10.1140/epja/i2015-15048-5 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We evaluate the decay width for the processes $f_1(1285) \to \pi^0 a_0(980)$
and $f_1(1285) \to \pi^0 f_0(980)$ taking into account that all three
resonances are dynamically generated from the meson-meson interaction, the
$f_1(1285)$ from $K^* \bar K -c.c$ and the $a_0(980)$, $f_0(980)$ from $\pi
\eta, K \bar K$ and $\pi \pi, K \bar K$ respectively. We use a triangular
mechanism similar to that of the $\eta(1405) \to \pi \pi \eta$, which provides
a decay width for $f_1(1285) \to \pi^0 a_0(980)$ with a branching fraction of
the order of 30%, in agreement with experiment. At the same time we evaluate
the decay width for the isospin forbidden $f_1(1285) \to \pi^0 f_0(980)$, which
appears when we consider different masses for the charged and neutral kaons,
and show that it is much more suppressed than in the $\eta(1405) \to \pi \pi
\eta$ case, but gives rise to a narrow shape of the $\pi^+ \pi^-$ distribution
similar to the one found in the $\eta(1405) \to \pi \pi \eta$ decay.
| [
{
"created": "Mon, 26 Jan 2015 18:07:44 GMT",
"version": "v1"
}
] | 2015-05-20 | [
[
"Aceti",
"F.",
""
],
[
"Dias",
"J. M.",
""
],
[
"Oset",
"E.",
""
]
] | We evaluate the decay width for the processes $f_1(1285) \to \pi^0 a_0(980)$ and $f_1(1285) \to \pi^0 f_0(980)$ taking into account that all three resonances are dynamically generated from the meson-meson interaction, the $f_1(1285)$ from $K^* \bar K -c.c$ and the $a_0(980)$, $f_0(980)$ from $\pi \eta, K \bar K$ and $\pi \pi, K \bar K$ respectively. We use a triangular mechanism similar to that of the $\eta(1405) \to \pi \pi \eta$, which provides a decay width for $f_1(1285) \to \pi^0 a_0(980)$ with a branching fraction of the order of 30%, in agreement with experiment. At the same time we evaluate the decay width for the isospin forbidden $f_1(1285) \to \pi^0 f_0(980)$, which appears when we consider different masses for the charged and neutral kaons, and show that it is much more suppressed than in the $\eta(1405) \to \pi \pi \eta$ case, but gives rise to a narrow shape of the $\pi^+ \pi^-$ distribution similar to the one found in the $\eta(1405) \to \pi \pi \eta$ decay. |
2301.05061 | Pankaj Borah | Pankaj Borah, Pradipta Ghosh, Sourov Roy and Abhijit Kumar Saha | Electroweak Phase Transition in a Right-Handed Neutrino Superfield
Extended NMSSM | 77 pages, 17 figures, 4 tables, discussion on semi-analytic
computation and gauge dependency added, version accepted for publication in
JHEP | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Supersymmetric models with singlet extensions can accommodate single- or
multi-step first-order phase transitions (FOPT) along the various constituent
field directions. Such a framework can also produce Gravitational Waves,
detectable at the upcoming space-based interferometers, e.g., U-DECIGO. We
explore the dynamics of electroweak phase transition and the production of
Gravitational Waves in an extended set-up of the Next-to-Minimal Supersymmetric
Standard Model (NMSSM) with a Standard Model singlet right-handed neutrino
superfield. We examine the role of the new parameters compared to NMSSM on the
phase transition dynamics and observe that the occurrence of a FOPT, an
essential requirement for Electroweak Baryogenesis, typically favours a
right-handed sneutrino state below 125 GeV. Our investigation shows how the
analysis can offer complementary probes for physics beyond the Standard Model
besides the collider searches.
| [
{
"created": "Thu, 12 Jan 2023 14:58:39 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Jan 2023 11:13:37 GMT",
"version": "v2"
},
{
"created": "Tue, 25 Jul 2023 16:59:13 GMT",
"version": "v3"
}
] | 2023-07-26 | [
[
"Borah",
"Pankaj",
""
],
[
"Ghosh",
"Pradipta",
""
],
[
"Roy",
"Sourov",
""
],
[
"Saha",
"Abhijit Kumar",
""
]
] | Supersymmetric models with singlet extensions can accommodate single- or multi-step first-order phase transitions (FOPT) along the various constituent field directions. Such a framework can also produce Gravitational Waves, detectable at the upcoming space-based interferometers, e.g., U-DECIGO. We explore the dynamics of electroweak phase transition and the production of Gravitational Waves in an extended set-up of the Next-to-Minimal Supersymmetric Standard Model (NMSSM) with a Standard Model singlet right-handed neutrino superfield. We examine the role of the new parameters compared to NMSSM on the phase transition dynamics and observe that the occurrence of a FOPT, an essential requirement for Electroweak Baryogenesis, typically favours a right-handed sneutrino state below 125 GeV. Our investigation shows how the analysis can offer complementary probes for physics beyond the Standard Model besides the collider searches. |
hep-ph/0412317 | Francesco Murgia | U. D'Alesio, F. Murgia (University and INFN, Cagliari, Italy) | Parton intrinsic motion: unpolarized cross sections and the Sivers
effect in inclusive particle production | LaTeX2e, 4 pages, 4 ps figures, uses ws-procs9x6. Talk delivered by
F. Murgia at the ``16th International Spin Physics Symposium'', SPIN2004,
October 10-16, 2004, Trieste, Italy | null | 10.1142/9789812701909_0045 | null | hep-ph | null | We present a detailed study, performed in the framework of LO perturbative
QCD with the inclusion of spin and k_T effects, of unpolarized cross sections
for the Drell-Yan process and for inclusive pion and photon production in
hadronic collisions, in different kinematical situations. We find a
satisfactory agreement between theoretical predictions and experimental data.
This supports the study of spin effects and transverse single spin asymmetries
(SSA) within the same scheme. We then present results for SSA, generated by the
so-called Sivers effect, in inclusive pion production in proton-proton
collisions.
| [
{
"created": "Tue, 21 Dec 2004 17:39:12 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"D'Alesio",
"U.",
"",
"University and INFN, Cagliari, Italy"
],
[
"Murgia",
"F.",
"",
"University and INFN, Cagliari, Italy"
]
] | We present a detailed study, performed in the framework of LO perturbative QCD with the inclusion of spin and k_T effects, of unpolarized cross sections for the Drell-Yan process and for inclusive pion and photon production in hadronic collisions, in different kinematical situations. We find a satisfactory agreement between theoretical predictions and experimental data. This supports the study of spin effects and transverse single spin asymmetries (SSA) within the same scheme. We then present results for SSA, generated by the so-called Sivers effect, in inclusive pion production in proton-proton collisions. |
0911.1974 | Fred Myhrer | F. Myhrer and A.W. Thomas | Understanding the proton's spin structure | Review article for J. Phys. G, 1 figure, 22 pages | J.Phys.G37:023101,2010 | 10.1088/0954-3899/37/2/023101 | ADP-09-16/T694 and JLAB-THY-09-1097 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the tremendous progress that has been towards an understanding of
how the spin of the proton is distributed on its quark and gluon constituents.
This is a problem that began in earnest twenty years ago with the discovery of
the proton ``spin crisis'' by the European Muon Collaboration. The discoveries
prompted by that original work have given us unprecedented insight into the
amount of spin carried by polarized gluons and the orbital angular momentum of
the quarks.
| [
{
"created": "Tue, 10 Nov 2009 19:19:16 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Myhrer",
"F.",
""
],
[
"Thomas",
"A. W.",
""
]
] | We discuss the tremendous progress that has been towards an understanding of how the spin of the proton is distributed on its quark and gluon constituents. This is a problem that began in earnest twenty years ago with the discovery of the proton ``spin crisis'' by the European Muon Collaboration. The discoveries prompted by that original work have given us unprecedented insight into the amount of spin carried by polarized gluons and the orbital angular momentum of the quarks. |
2012.12165 | Marcel Wald | Muslem Rahimi, Marcel Wald | QCD sum rules for parameters of the $B$-meson distribution amplitudes | 31 pages, 12 figures; corrected format, included source files,
improved numerical analysis | Phys. Rev. D 104, 016027 (2021) | 10.1103/PhysRevD.104.016027 | P3H-20-082, SI-HEP-2020-35 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We obtain new estimates for the parameters $\lambda_{E}^2$, $\lambda_H^2$ and
their ratio $\mathcal{R} = \lambda_{E}^2/\lambda_H^2$, which appear in the
second moments of the $B$-meson light-cone distribution amplitudes defined in
the heavy-quark effective field theory. The computation is based on two-point
QCD sum rules for the diagonal correlation function and includes all
contributions up to mass dimension seven in the operator-product expansion. For
the ratio we get $\mathcal{R} = (0.1 \pm 0.1)$ with $\lambda_H^2 = (0.15 \pm
0.05) \, \text{GeV}^2$ and $\lambda_E^2 = (0.01 \pm 0.01) \, \text{GeV}^2$.
| [
{
"created": "Tue, 22 Dec 2020 16:55:48 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Jul 2021 15:16:59 GMT",
"version": "v2"
},
{
"created": "Wed, 4 Aug 2021 13:19:40 GMT",
"version": "v3"
}
] | 2021-08-11 | [
[
"Rahimi",
"Muslem",
""
],
[
"Wald",
"Marcel",
""
]
] | We obtain new estimates for the parameters $\lambda_{E}^2$, $\lambda_H^2$ and their ratio $\mathcal{R} = \lambda_{E}^2/\lambda_H^2$, which appear in the second moments of the $B$-meson light-cone distribution amplitudes defined in the heavy-quark effective field theory. The computation is based on two-point QCD sum rules for the diagonal correlation function and includes all contributions up to mass dimension seven in the operator-product expansion. For the ratio we get $\mathcal{R} = (0.1 \pm 0.1)$ with $\lambda_H^2 = (0.15 \pm 0.05) \, \text{GeV}^2$ and $\lambda_E^2 = (0.01 \pm 0.01) \, \text{GeV}^2$. |
1608.05218 | Valery Schegelsky A | V.A. Schegelsky and M.G. Ryskin | Small size sources of secondaries observed in pp-collisions via
Bose-Einstein correlations at the LHC ATLAS experiment | ATLAS management did ask me to withdraw this article to be publish
later on as Collaboration paper | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Bose-Einstein correlations in proton-proton collisions at the LHC are well
descried by the formula with two different scales. It is shown for the first
time that the pions are produced by few small size sources distributed over a
much larger area in impact parameter space occupied by the interaction
amplitude. The dependence of the two radii obtained in this procedure on the
charged particle density and the mean transverse momentum of the pion/hadron in
the correlated pair are discussed.
| [
{
"created": "Thu, 18 Aug 2016 09:39:05 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Nov 2016 18:15:33 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Apr 2018 19:35:42 GMT",
"version": "v3"
},
{
"created": "Tue, 18 Jun 2019 19:28:01 GMT",
"version": "v4"
}
] | 2019-06-21 | [
[
"Schegelsky",
"V. A.",
""
],
[
"Ryskin",
"M. G.",
""
]
] | Bose-Einstein correlations in proton-proton collisions at the LHC are well descried by the formula with two different scales. It is shown for the first time that the pions are produced by few small size sources distributed over a much larger area in impact parameter space occupied by the interaction amplitude. The dependence of the two radii obtained in this procedure on the charged particle density and the mean transverse momentum of the pion/hadron in the correlated pair are discussed. |
2001.05110 | Li-Ye Xiao | Li-Ye Xiao, Kai-Lei Wang, Ming-Sheng Liu and Xian-Hui Zhong | Possible interpretation of the newly observed $\Omega_b$ states | 8 pages,3 figures | null | 10.1140/epjc/s10052-020-7823-z | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inspired by the newly observed $\Omega_b$ states by the LHCb Collaboration,
we investigate the two-body strong decays of the low-lying $\lambda$-mode
$\Omega_b$ baryons up to $N=2$ shell using the chiral quark model within the
$j$-$j$ coupling scheme. Our results indicate that: (i) the newly observed
states $\Omega_b(6316)^-$ and $\Omega_b(6330)^-$ are good candidates of the
light spin $j=1$ states, while the spin-parity $J^P=1/2^-$ and $J^P=3/2^-$
cannot be distinguished. The other two states, $\Omega_b(6340)$ and
$\Omega_b(6350)$ mostly correspond to the light spin $j=2$ states, while the
spin-parity $J^P=3/2^-$ and $J^P=5/2^-$ cannot be distinguished as well.(ii)
The $2S$ states with spin-parity $J^P=1/2^+$ and $J^P=3/2^+$, respectively,
might be narrow states with a width of $\Gamma<2$ MeV. (iii) The $1D$ states
are not broad and the total decay widths vary from several to dozens of MeV,
which have a good potential to be observed in future experiments.
| [
{
"created": "Wed, 15 Jan 2020 02:48:10 GMT",
"version": "v1"
}
] | 2020-04-22 | [
[
"Xiao",
"Li-Ye",
""
],
[
"Wang",
"Kai-Lei",
""
],
[
"Liu",
"Ming-Sheng",
""
],
[
"Zhong",
"Xian-Hui",
""
]
] | Inspired by the newly observed $\Omega_b$ states by the LHCb Collaboration, we investigate the two-body strong decays of the low-lying $\lambda$-mode $\Omega_b$ baryons up to $N=2$ shell using the chiral quark model within the $j$-$j$ coupling scheme. Our results indicate that: (i) the newly observed states $\Omega_b(6316)^-$ and $\Omega_b(6330)^-$ are good candidates of the light spin $j=1$ states, while the spin-parity $J^P=1/2^-$ and $J^P=3/2^-$ cannot be distinguished. The other two states, $\Omega_b(6340)$ and $\Omega_b(6350)$ mostly correspond to the light spin $j=2$ states, while the spin-parity $J^P=3/2^-$ and $J^P=5/2^-$ cannot be distinguished as well.(ii) The $2S$ states with spin-parity $J^P=1/2^+$ and $J^P=3/2^+$, respectively, might be narrow states with a width of $\Gamma<2$ MeV. (iii) The $1D$ states are not broad and the total decay widths vary from several to dozens of MeV, which have a good potential to be observed in future experiments. |
1108.0483 | Kaushik Bhattacharya | Kaushik Bhattacharya, Suratna Das | Thermodynamics of the Lee-Wick partners: An alternative approach | 17 pages, 2 figures. Some minor typos corrected. To be published in
Physical Review D | Phys.Rev.D84:045023,2011 | 10.1103/PhysRevD.84.045023 | null | hep-ph gr-qc hep-th | http://creativecommons.org/licenses/publicdomain/ | It was pointed out some time ago that there can be two variations in which
the divergences of a quantum field theory can be tamed using the ideas
presented by Lee and Wick. In one variation the Lee-Wick partners of the normal
fields live in an indefinite metric Hilbert space but have positive energy and
in the other variation the Lee-Wick partners can live in a normal Hilbert space
but carry negative energy. Quantum mechanically the two variations mainly
differ in the way the fields are quantized. In this article the second
variation of Lee and Wick's idea is discussed. Using statistical mechanical
methods the energy density, pressure and entropy density of the negative energy
Lee-Wick fields have been calculated. The results exactly match with the
thermodynamic results of the conventional, positive energy Lee-Wick fields. The
result sheds some light on the second variation of Lee-Wick's idea. The result
seems to say that the thermodynamics of the theories do not care about the way
they are quantized.
| [
{
"created": "Tue, 2 Aug 2011 05:21:30 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Aug 2011 11:37:30 GMT",
"version": "v2"
}
] | 2011-11-10 | [
[
"Bhattacharya",
"Kaushik",
""
],
[
"Das",
"Suratna",
""
]
] | It was pointed out some time ago that there can be two variations in which the divergences of a quantum field theory can be tamed using the ideas presented by Lee and Wick. In one variation the Lee-Wick partners of the normal fields live in an indefinite metric Hilbert space but have positive energy and in the other variation the Lee-Wick partners can live in a normal Hilbert space but carry negative energy. Quantum mechanically the two variations mainly differ in the way the fields are quantized. In this article the second variation of Lee and Wick's idea is discussed. Using statistical mechanical methods the energy density, pressure and entropy density of the negative energy Lee-Wick fields have been calculated. The results exactly match with the thermodynamic results of the conventional, positive energy Lee-Wick fields. The result sheds some light on the second variation of Lee-Wick's idea. The result seems to say that the thermodynamics of the theories do not care about the way they are quantized. |
2405.03265 | Yuepeng Guan | Yuepeng Guan, Shinya Matsuzaki | Ladder top-quark condensation imprints in supercooled electroweak phase
transition | 18 pages, 13 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The electroweak (EW) phase transition in the early Universe might be
supercooled due to the presence of the classical scale invariance involving
Beyond the Standard Model (BSM) sectors and the supercooling could persist down
till a later epoch around which the QCD chiral phase transition is supposed to
take place. Since this supercooling period keeps masslessness for all the six
SM quarks, it has simply been argued that the QCD phase transition is the first
order, and so is the EW one. However, not only the QCD coupling but also the
top Yukawa and the Higgs quartic couplings get strong at around the QCD scale
due to the renormalization group running, hence this scenario is potentially
subject to a rigorous nonperturbative analysis. In this work, we employ the
ladder Schwinger-Dyson (LSD) analysis based on the Cornwall-Jackiw-Tomboulis
formalism at the two-loop level in such a gauge-Higgs-Yukawa system. We show
that the chiral broken QCD vacuum emerges with the nonperturbative top
condensate and the lightness of all six quarks is guaranteed due to the
accidental U(1) axial symmetry presented in the top-Higgs sector. We employ a
quark-meson model-like description in the mean field approximation to address
the impact on the EW phase transition arising due to the top quark condensation
at the QCD phase transition epoch. In the model, the LSD results are encoded to
constrain the model parameter space. We then observe the cosmological phase
transition of the first-order type and discuss the induced gravitational wave
(GW) productions. We find that in addition to the conventional GW signals
sourced from an expected BSM at around or over the TeV scale, the dynamical
topponium-Higgs system can yield another power spectrum sensitive to the BBO,
LISA, and DECIGO, etc.
| [
{
"created": "Mon, 6 May 2024 08:36:57 GMT",
"version": "v1"
}
] | 2024-05-07 | [
[
"Guan",
"Yuepeng",
""
],
[
"Matsuzaki",
"Shinya",
""
]
] | The electroweak (EW) phase transition in the early Universe might be supercooled due to the presence of the classical scale invariance involving Beyond the Standard Model (BSM) sectors and the supercooling could persist down till a later epoch around which the QCD chiral phase transition is supposed to take place. Since this supercooling period keeps masslessness for all the six SM quarks, it has simply been argued that the QCD phase transition is the first order, and so is the EW one. However, not only the QCD coupling but also the top Yukawa and the Higgs quartic couplings get strong at around the QCD scale due to the renormalization group running, hence this scenario is potentially subject to a rigorous nonperturbative analysis. In this work, we employ the ladder Schwinger-Dyson (LSD) analysis based on the Cornwall-Jackiw-Tomboulis formalism at the two-loop level in such a gauge-Higgs-Yukawa system. We show that the chiral broken QCD vacuum emerges with the nonperturbative top condensate and the lightness of all six quarks is guaranteed due to the accidental U(1) axial symmetry presented in the top-Higgs sector. We employ a quark-meson model-like description in the mean field approximation to address the impact on the EW phase transition arising due to the top quark condensation at the QCD phase transition epoch. In the model, the LSD results are encoded to constrain the model parameter space. We then observe the cosmological phase transition of the first-order type and discuss the induced gravitational wave (GW) productions. We find that in addition to the conventional GW signals sourced from an expected BSM at around or over the TeV scale, the dynamical topponium-Higgs system can yield another power spectrum sensitive to the BBO, LISA, and DECIGO, etc. |
1108.0887 | Van Mayes | James A. Maxin, Van E. Mayes, and D.V. Nanopoulos | Proton Stability and Dark Matter in a Realistic String MSSM | Expanded discussion of Z' boson phenomenology. Accepted for
publication to Physical Review D. arXiv admin note: text overlap with
arXiv:1103.6035 | Phys. Rev. D 84: 106009, 2011 | 10.1103/PhysRevD.84.106009 | ACT-11-11; MIFPA-11-35 | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We demonstrate the existence of an extra nonanomalous U(1) gauge symmetry in
a three-generation Pati-Salam model constructed with intersecting D6-branes in
Type IIA string theory on a T^6/(Z_2 \times Z_2) orientifold. This extra U(1)
forbids all dimension-4, 5, and 6 operators which mediate proton decay in the
MSSM. Moreover, this results in the effective promotion of baryon and lepton
number to local gauge symmetries, which can potentially result in leptophobic
and leptophilic $Z'$ bosons observable at the LHC. Furthermore, it is not
necessary to invoke R-parity to forbid the dimension-4 operators which allow
rapid proton decay. However, R-parity may arise naturally from a spontaneously
broken U(1)_{B-L}. Assuming the presence of R-parity, we then study the direct
detection cross-sections for neutralino dark matter, including the latest
constraints from the XENON100 experiment. We find that these limits are now
within required range necessary to begin testing the model.
| [
{
"created": "Wed, 3 Aug 2011 16:35:19 GMT",
"version": "v1"
},
{
"created": "Sat, 22 Oct 2011 00:28:49 GMT",
"version": "v2"
}
] | 2013-02-26 | [
[
"Maxin",
"James A.",
""
],
[
"Mayes",
"Van E.",
""
],
[
"Nanopoulos",
"D. V.",
""
]
] | We demonstrate the existence of an extra nonanomalous U(1) gauge symmetry in a three-generation Pati-Salam model constructed with intersecting D6-branes in Type IIA string theory on a T^6/(Z_2 \times Z_2) orientifold. This extra U(1) forbids all dimension-4, 5, and 6 operators which mediate proton decay in the MSSM. Moreover, this results in the effective promotion of baryon and lepton number to local gauge symmetries, which can potentially result in leptophobic and leptophilic $Z'$ bosons observable at the LHC. Furthermore, it is not necessary to invoke R-parity to forbid the dimension-4 operators which allow rapid proton decay. However, R-parity may arise naturally from a spontaneously broken U(1)_{B-L}. Assuming the presence of R-parity, we then study the direct detection cross-sections for neutralino dark matter, including the latest constraints from the XENON100 experiment. We find that these limits are now within required range necessary to begin testing the model. |
hep-ph/0505092 | Alexander V. Kuznetsov | A.V. Kuznetsov, N.V. Mikheev (Yaroslavl State (P.G. Demidov)
University, Russia), G.G. Raffelt (Max-Planck-Institut fuer Physik
(Werner-Heisenberg-Institut), Germany), L.A. Vassilevskaya (Yaroslavl State
(P.G. Demidov) University, Russia) | Neutrino dispersion in external magnetic fields | 9 pages, 1 figure, revtex. Version to appear in Phys. Rev. D
(presentation improved, reference list revised, numerical error in Eq.(41)
corrected, conclusions unchanged) | Phys.Rev.D73:023001,2006; Erratum-ibid.D73:029903,2006 | 10.1103/PhysRevD.73.023001 10.1103/PhysRevD.73.029903 | YARU-HE-05/02; MPP-2005-43 | hep-ph | null | We calculate the neutrino self-energy operator Sigma (p) in the presence of a
magnetic field B. In particular, we consider the weak-field limit e B <<
m_\ell^2, where m_\ell is the charged-lepton mass corresponding to the neutrino
flavor \nu_\ell, and we consider a "moderate field" m_\ell^2 << e B << m_W^2.
Our results differ substantially from the previous literature. For a moderate
field, we show that it is crucial to include the contributions from all Landau
levels of the intermediate charged lepton, not just the ground-state. For the
conditions of the early universe where the background medium consists of a
charge-symmetric plasma, the pure B-field contribution to the neutrino
dispersion relation is proportional to (e B)^2 and thus comparable to the
contribution of the magnetized plasma.
| [
{
"created": "Wed, 11 May 2005 12:13:01 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Dec 2005 11:14:09 GMT",
"version": "v2"
}
] | 2014-11-18 | [
[
"Kuznetsov",
"A. V.",
"",
"Yaroslavl State"
],
[
"Mikheev",
"N. V.",
"",
"Yaroslavl State"
],
[
"Raffelt",
"G. G.",
"",
"Max-Planck-Institut fuer Physik"
],
[
"Vassilevskaya",
"L. A.",
"",
"Yaroslavl State"
]
] | We calculate the neutrino self-energy operator Sigma (p) in the presence of a magnetic field B. In particular, we consider the weak-field limit e B << m_\ell^2, where m_\ell is the charged-lepton mass corresponding to the neutrino flavor \nu_\ell, and we consider a "moderate field" m_\ell^2 << e B << m_W^2. Our results differ substantially from the previous literature. For a moderate field, we show that it is crucial to include the contributions from all Landau levels of the intermediate charged lepton, not just the ground-state. For the conditions of the early universe where the background medium consists of a charge-symmetric plasma, the pure B-field contribution to the neutrino dispersion relation is proportional to (e B)^2 and thus comparable to the contribution of the magnetized plasma. |
hep-ph/0611218 | Ben Gripaios | Ben Gripaios | Neutrinos in a Sterile Throat | 27 pages, 1 figure. Sign error corrected | Nucl.Phys.B768:157-176,2007 | 10.1016/j.nuclphysb.2007.01.019 | OUTP-0619P | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider field-theoretic models of a warped extra dimension with multiple
throats, in which fermions that are singlets of the Standard Model gauge group
propagate in a separate throat from the Standard Model fields, which we call
the sterile throat.
The singlets mix with Standard Model fields via interactions localized on the
UV brane that connects the two throats. This leads to three, light,
mostly-active, Majorana neutrinos via a higher-dimensional see-saw mechanism,
together with Kaluza-Klein towers of mostly-sterile neutrinos, whose scale is
set by the warp factor in the sterile throat and can be very low if the throat
is deep. We suggest that a model of this kind may explain all the neutrino
data, reconciling the LSND result with astrophysical constraints.
| [
{
"created": "Thu, 16 Nov 2006 14:31:52 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Dec 2009 15:56:13 GMT",
"version": "v2"
}
] | 2009-12-16 | [
[
"Gripaios",
"Ben",
""
]
] | We consider field-theoretic models of a warped extra dimension with multiple throats, in which fermions that are singlets of the Standard Model gauge group propagate in a separate throat from the Standard Model fields, which we call the sterile throat. The singlets mix with Standard Model fields via interactions localized on the UV brane that connects the two throats. This leads to three, light, mostly-active, Majorana neutrinos via a higher-dimensional see-saw mechanism, together with Kaluza-Klein towers of mostly-sterile neutrinos, whose scale is set by the warp factor in the sterile throat and can be very low if the throat is deep. We suggest that a model of this kind may explain all the neutrino data, reconciling the LSND result with astrophysical constraints. |
hep-ph/9707432 | Deog Ki Hong | Deog Ki Hong (Pusan University) | Magnetic Catalysis in Quantum Electrodynamics | 9 pages, RevTeX, 2 Postscript figures, uses epsf.sty | Phys.Rev. D57 (1998) 3759-3762 | 10.1103/PhysRevD.57.3759 | SNUTP 97-053 | hep-ph hep-th | null | We derive the (Wilsonian) low energy effective Lagrangian for Quantum
Electrodynamics under external constant magnetic field by integrating out all
electrons except those in the lowest Landau level. We find the one-loop
effective Lagrangian contains a marginal four-Fermi interaction with anomalous
dimension, ${(\ln2)^2\over 2\pi^2}e^4$. Renormalization group analysis shows
that the four-Fermi interaction will break chiral symmetry in QED if the
external magnetic field is extremely strong, $B>10^{42}$ gauss, or if the
Landau gap, $\sqrt{|eB|}>6.5 \times 10^{10}$ GeV.
| [
{
"created": "Wed, 23 Jul 1997 15:31:26 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Hong",
"Deog Ki",
"",
"Pusan University"
]
] | We derive the (Wilsonian) low energy effective Lagrangian for Quantum Electrodynamics under external constant magnetic field by integrating out all electrons except those in the lowest Landau level. We find the one-loop effective Lagrangian contains a marginal four-Fermi interaction with anomalous dimension, ${(\ln2)^2\over 2\pi^2}e^4$. Renormalization group analysis shows that the four-Fermi interaction will break chiral symmetry in QED if the external magnetic field is extremely strong, $B>10^{42}$ gauss, or if the Landau gap, $\sqrt{|eB|}>6.5 \times 10^{10}$ GeV. |
2204.06225 | Jason Aebischer | Jason Aebischer and Benjam\'in Grinstein | The $B_c$ decay rate in the Standard Model | 5 pages, Contribution to the proceedings of the 30th International
Symposium on Lepton Photon Interactions at High Energies, hosted by the
University of Manchester, 10-14 January 2022 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Standard Model decay rate of the $B_c$ meson is discussed together with a
novel approach based on the usage of experimental data in combination with an
operator product expansion. In the new method differences of $B,\,D$ and $B_c$
meson decay rates are considered, for which the free-quark contributions drop
out, leading to a reduction of the theory prediction.
| [
{
"created": "Wed, 13 Apr 2022 07:57:47 GMT",
"version": "v1"
}
] | 2022-04-14 | [
[
"Aebischer",
"Jason",
""
],
[
"Grinstein",
"Benjamín",
""
]
] | The Standard Model decay rate of the $B_c$ meson is discussed together with a novel approach based on the usage of experimental data in combination with an operator product expansion. In the new method differences of $B,\,D$ and $B_c$ meson decay rates are considered, for which the free-quark contributions drop out, leading to a reduction of the theory prediction. |
2105.06261 | Chen Gang | Hong-ge Xu, Zhi-Lei She, Dai-Mei Zhou, Liang Zheng, Xiao-Lin Kang,
Gang Chen, Ben-Hao Sa | Investigation of exotic state X(3872) in $pp$ collisions at $\sqrt{s}=$7
and 13 TeV | 6 pages, 3 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We have used the dynamically constrained phase space coalescence model to
study the production of the exotic state $X(3872)$ based on the hadronic final
states generated by the parton and hadron cascade model (PACIAE) with $|y|<1$
and $p_T < 15.5$ GeV/c in $pp$ collisions at $\sqrt{s}=7$ and 13 TeV,
respectively. Here the $X(3872)$ is assumed to consist of bound state $D\bar
{D^*}$, which can form three possible structures for the tetraquark state, the
nucleus-like state, and the molecular state. The yields of three different
structures $X(3872)$ were predicted. The transverse momentum distribution and
the rapidity distribution of three different structures $X(3872)$ are also
presented. Sizable difference can be found in the transverse momentum and
rapidity distributions for the three different $X(3872)$ structures.
| [
{
"created": "Thu, 13 May 2021 13:07:04 GMT",
"version": "v1"
},
{
"created": "Fri, 18 Jun 2021 04:10:00 GMT",
"version": "v2"
},
{
"created": "Thu, 28 Oct 2021 12:47:23 GMT",
"version": "v3"
}
] | 2021-10-29 | [
[
"Xu",
"Hong-ge",
""
],
[
"She",
"Zhi-Lei",
""
],
[
"Zhou",
"Dai-Mei",
""
],
[
"Zheng",
"Liang",
""
],
[
"Kang",
"Xiao-Lin",
""
],
[
"Chen",
"Gang",
""
],
[
"Sa",
"Ben-Hao",
""
]
] | We have used the dynamically constrained phase space coalescence model to study the production of the exotic state $X(3872)$ based on the hadronic final states generated by the parton and hadron cascade model (PACIAE) with $|y|<1$ and $p_T < 15.5$ GeV/c in $pp$ collisions at $\sqrt{s}=7$ and 13 TeV, respectively. Here the $X(3872)$ is assumed to consist of bound state $D\bar {D^*}$, which can form three possible structures for the tetraquark state, the nucleus-like state, and the molecular state. The yields of three different structures $X(3872)$ were predicted. The transverse momentum distribution and the rapidity distribution of three different structures $X(3872)$ are also presented. Sizable difference can be found in the transverse momentum and rapidity distributions for the three different $X(3872)$ structures. |
1509.02530 | Pran Nath | Bryan Kaufman, Pran Nath, Brent D Nelson, Andrew Spisak | Light Stops and Observation of Supersymmetry at LHC RUN-II | 21pages, 8 figures. Version published in PRD | null | 10.1103/PhysRevD.92.095021 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Light stops consistent with the Higgs boson mass of $\sim126\,{\rm GeV}$ are
investigated within the framework of minimal supergravity. It is shown that
models with light stops which are also consistent with the thermal relic
density constraints require stop coannihilation with the neutralino LSP. The
analysis shows that the residual set of parameter points with light stops
satisfying both the Higgs mass and the relic density constraints lie within a
series of thin strips in the $m_0-m_{1/2}$ plane for different values of
$A_0/m_0$. Consequently, this region of minimal supergravity parameter space
makes a number of very precise predictions. It is found that light stops of
mass down to 400~GeV or lower can exist consistent with all constraints. A
signal analysis for this class of models at LHC RUN-II is carried out and the
dominant signals for their detection identified. Also computed is the minimum
integrated luminosity for $5\sigma$ discovery of the models analyzed. If
supersymmetry is realized in this manner, the stop masses can be as low as
400~GeV or lower, and the mass gap between the lightest neutralino and lightest
stop will be approximately 30-40~GeV. We have optimized the ATLAS signal
regions specifically for stop searches in the parameter space and find that a
stop with mass $\sim 375\,{\rm GeV}$ can be discovered with as little as $\sim$
60~fb$^{-1}$ of integrated luminosity at RUN-II of the LHC; the integrated
luminosity needed for discovery could be further reduced with more efficient
signature analyses. The direct detection of dark matter in this class of models
is also discussed. It is found that dark matter cross sections lie close to,
but above, coherent neutrino scattering and would require multi-ton detectors
such as LZ to see a signal of dark matter for this class of models.
| [
{
"created": "Tue, 8 Sep 2015 20:08:59 GMT",
"version": "v1"
},
{
"created": "Wed, 18 May 2016 22:08:02 GMT",
"version": "v2"
}
] | 2016-05-20 | [
[
"Kaufman",
"Bryan",
""
],
[
"Nath",
"Pran",
""
],
[
"Nelson",
"Brent D",
""
],
[
"Spisak",
"Andrew",
""
]
] | Light stops consistent with the Higgs boson mass of $\sim126\,{\rm GeV}$ are investigated within the framework of minimal supergravity. It is shown that models with light stops which are also consistent with the thermal relic density constraints require stop coannihilation with the neutralino LSP. The analysis shows that the residual set of parameter points with light stops satisfying both the Higgs mass and the relic density constraints lie within a series of thin strips in the $m_0-m_{1/2}$ plane for different values of $A_0/m_0$. Consequently, this region of minimal supergravity parameter space makes a number of very precise predictions. It is found that light stops of mass down to 400~GeV or lower can exist consistent with all constraints. A signal analysis for this class of models at LHC RUN-II is carried out and the dominant signals for their detection identified. Also computed is the minimum integrated luminosity for $5\sigma$ discovery of the models analyzed. If supersymmetry is realized in this manner, the stop masses can be as low as 400~GeV or lower, and the mass gap between the lightest neutralino and lightest stop will be approximately 30-40~GeV. We have optimized the ATLAS signal regions specifically for stop searches in the parameter space and find that a stop with mass $\sim 375\,{\rm GeV}$ can be discovered with as little as $\sim$ 60~fb$^{-1}$ of integrated luminosity at RUN-II of the LHC; the integrated luminosity needed for discovery could be further reduced with more efficient signature analyses. The direct detection of dark matter in this class of models is also discussed. It is found that dark matter cross sections lie close to, but above, coherent neutrino scattering and would require multi-ton detectors such as LZ to see a signal of dark matter for this class of models. |
1612.07123 | Wolfgang Schweiger | S. Kofler and W. Schweiger | A perturbative QCD approach to $\pi^- p \rightarrow D^- \Lambda_c^+$ | Talk presented by W. Schweiger at "Light Cone 2016", Lisbon, Sep.
5-8, 2016 | null | 10.1007/s00601-016-1197-7 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We employ the generalized parton picture to analyze the reaction $\pi^- p
\rightarrow D^- \Lambda_c^+$. Thereby it is assumed that the process amplitude
factorizes into one for the perturbatively calculable subprocess $\bar{u}\
u\rightarrow \bar{c}\ c$ and hadronic matrix elements that can be parameterized
in terms of generalized parton distributions for the $\pi^-\rightarrow D^-$ and
$p\rightarrow \Lambda_c^+$ transitions, respectively. Representing these parton
distributions in terms of valence-quark light-cone wave functions for $\pi$,
$D$, $p$ and $\Lambda_c$ allows us to make numerical predictions for
unpolarized differential and integrated cross sections as well as spin
observables. In the kinematical region where this approach is supposed to work,
i.e. $s\gtrsim 20$~GeV$^2$ and in the forward hemisphere, the resulting cross
sections are of the order of nb. This is a finding that could be of interest in
view of plans to measure $\pi^- p \rightarrow D^- \Lambda_c^+$, e.g., at J-PARC
or COMPASS.
| [
{
"created": "Wed, 21 Dec 2016 14:07:48 GMT",
"version": "v1"
}
] | 2017-03-08 | [
[
"Kofler",
"S.",
""
],
[
"Schweiger",
"W.",
""
]
] | We employ the generalized parton picture to analyze the reaction $\pi^- p \rightarrow D^- \Lambda_c^+$. Thereby it is assumed that the process amplitude factorizes into one for the perturbatively calculable subprocess $\bar{u}\ u\rightarrow \bar{c}\ c$ and hadronic matrix elements that can be parameterized in terms of generalized parton distributions for the $\pi^-\rightarrow D^-$ and $p\rightarrow \Lambda_c^+$ transitions, respectively. Representing these parton distributions in terms of valence-quark light-cone wave functions for $\pi$, $D$, $p$ and $\Lambda_c$ allows us to make numerical predictions for unpolarized differential and integrated cross sections as well as spin observables. In the kinematical region where this approach is supposed to work, i.e. $s\gtrsim 20$~GeV$^2$ and in the forward hemisphere, the resulting cross sections are of the order of nb. This is a finding that could be of interest in view of plans to measure $\pi^- p \rightarrow D^- \Lambda_c^+$, e.g., at J-PARC or COMPASS. |
2203.11462 | Yisheng Song | Yisheng Song | Co-positivity of tensors and bounded from below conditions of CP
conserving two-Higgs-doublet potential | 17 pages | International Journal of Modern Physics A 38:31 (2023), 2350164 | 10.1142/S0217751X23501646 | null | hep-ph math-ph math.MP math.OC | http://creativecommons.org/licenses/by/4.0/ | In this paper, the analytic sufficient and necessary conditions are obtained
for the CP conserving two-Higgs-doublet potential to be bounded from below by
using the co-positivity of tensors. This is achieved by treating the potential
as a quartic homogeneous polynomial about the moduli of the two Higgs doublet
fields, where the 'angles' is described as the misalignment of the two
doublets, then solving three minimum problems with respect to the misalignment.
Finally, the analytic conditions are established with the help of the
corresponding theory and methods of higher order tensors.
| [
{
"created": "Tue, 22 Mar 2022 05:01:18 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Dec 2022 10:55:58 GMT",
"version": "v2"
},
{
"created": "Sun, 8 Jan 2023 00:22:40 GMT",
"version": "v3"
},
{
"created": "Sat, 4 Feb 2023 04:27:14 GMT",
"version": "v4"
},
{
"created": "Mon, 26 Jun 2023 09:02:13 GMT",
"version": "v5"
},
{
"created": "Tue, 14 Nov 2023 08:07:34 GMT",
"version": "v6"
}
] | 2024-01-29 | [
[
"Song",
"Yisheng",
""
]
] | In this paper, the analytic sufficient and necessary conditions are obtained for the CP conserving two-Higgs-doublet potential to be bounded from below by using the co-positivity of tensors. This is achieved by treating the potential as a quartic homogeneous polynomial about the moduli of the two Higgs doublet fields, where the 'angles' is described as the misalignment of the two doublets, then solving three minimum problems with respect to the misalignment. Finally, the analytic conditions are established with the help of the corresponding theory and methods of higher order tensors. |
1602.00590 | Melissa van Beekveld | Melissa van Beekveld, Wim Beenakker, Sascha Caron and Roberto Ruiz de
Austri | The case for 100 GeV bino dark matter: A dedicated LHC tri-lepton search | Published in JHEP | null | 10.1007/JHEP04(2016)154 | null | hep-ph astro-ph.HE hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Global fit studies performed in the pMSSM and the photon excess signal
originating from the Galactic Center seem to suggest compressed electroweak
supersymmetric spectra with a $\sim$100 GeV bino-like dark matter particle. We
find that these scenarios are not probed by traditional electroweak
supersymmetry searches at the LHC. We propose to extend the ATLAS and CMS
electroweak supersymmetry searches with an improved strategy for bino-like dark
matter, focusing on chargino plus next-to-lightest neutralino production, with
a subsequent decay into a tri-lepton final state. We explore the sensitivity
for pMSSM scenarios with $\Delta m = m_{\rm NLSP} - m_{\rm LSP} \sim (5 - 50)$
GeV in the $\sqrt{s} = 14$ TeV run of the LHC. Counterintuitively, we find that
the requirement of low missing transverse energy increases the sensitivity
compared to the current ATLAS and CMS searches. With 300 fb$^{-1}$ of data we
expect the LHC experiments to be able to discover these supersymmetric spectra
with mass gaps down to $\Delta m \sim 9$ GeV for DM masses between 40 and 140
GeV. We stress the importance of a dedicated search strategy that targets
precisely these favored pMSSM spectra.
| [
{
"created": "Mon, 1 Feb 2016 16:47:11 GMT",
"version": "v1"
},
{
"created": "Mon, 2 May 2016 08:12:22 GMT",
"version": "v2"
}
] | 2016-05-03 | [
[
"van Beekveld",
"Melissa",
""
],
[
"Beenakker",
"Wim",
""
],
[
"Caron",
"Sascha",
""
],
[
"de Austri",
"Roberto Ruiz",
""
]
] | Global fit studies performed in the pMSSM and the photon excess signal originating from the Galactic Center seem to suggest compressed electroweak supersymmetric spectra with a $\sim$100 GeV bino-like dark matter particle. We find that these scenarios are not probed by traditional electroweak supersymmetry searches at the LHC. We propose to extend the ATLAS and CMS electroweak supersymmetry searches with an improved strategy for bino-like dark matter, focusing on chargino plus next-to-lightest neutralino production, with a subsequent decay into a tri-lepton final state. We explore the sensitivity for pMSSM scenarios with $\Delta m = m_{\rm NLSP} - m_{\rm LSP} \sim (5 - 50)$ GeV in the $\sqrt{s} = 14$ TeV run of the LHC. Counterintuitively, we find that the requirement of low missing transverse energy increases the sensitivity compared to the current ATLAS and CMS searches. With 300 fb$^{-1}$ of data we expect the LHC experiments to be able to discover these supersymmetric spectra with mass gaps down to $\Delta m \sim 9$ GeV for DM masses between 40 and 140 GeV. We stress the importance of a dedicated search strategy that targets precisely these favored pMSSM spectra. |
1904.11990 | Christopher Verhaaren | Zackaria Chacko, Can Kilic, Saereh Najjari, Christopher B. Verhaaren | Collider Signals of the Mirror Twin Higgs through the Hypercharge Portal | 28 pages, 9 figures; Updated to published version | Phys. Rev. D 100, 035037 (2019) | 10.1103/PhysRevD.100.035037 | MITP/18-113, UTTG-25-18 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the collider signals arising from kinetic mixing between the
hypercharge gauge boson of the Standard Model and its twin counterpart in the
Mirror Twin Higgs model, in the framework in which the twin photon is massive.
Through the mixing, the Standard Model fermions acquire charges under the
mirror photon and the mirror Z boson. We determine the current experimental
bounds on this scenario, and show that the mixing can be large enough to
discover both the twin photon and the twin Z at the LHC, or at a future 100 TeV
hadron collider, with dilepton resonances being a particularly conspicuous
signal. We show that, in simple models, measuring the masses of both the mirror
photon and mirror Z, along with the corresponding event rates in the dilepton
channel, overdetermines the system, and can be used to test these theories.
| [
{
"created": "Fri, 26 Apr 2019 18:00:02 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Aug 2019 16:26:36 GMT",
"version": "v2"
}
] | 2019-09-02 | [
[
"Chacko",
"Zackaria",
""
],
[
"Kilic",
"Can",
""
],
[
"Najjari",
"Saereh",
""
],
[
"Verhaaren",
"Christopher B.",
""
]
] | We consider the collider signals arising from kinetic mixing between the hypercharge gauge boson of the Standard Model and its twin counterpart in the Mirror Twin Higgs model, in the framework in which the twin photon is massive. Through the mixing, the Standard Model fermions acquire charges under the mirror photon and the mirror Z boson. We determine the current experimental bounds on this scenario, and show that the mixing can be large enough to discover both the twin photon and the twin Z at the LHC, or at a future 100 TeV hadron collider, with dilepton resonances being a particularly conspicuous signal. We show that, in simple models, measuring the masses of both the mirror photon and mirror Z, along with the corresponding event rates in the dilepton channel, overdetermines the system, and can be used to test these theories. |
hep-ph/9906404 | Karapet A. Ispiryan | R. O. Avakian, L. A. Gevorgian, K. A. Ispirian, R. K. Ispirian | Stimulated Radiation of Particles in Crystallic Undulators | 8 pages, Latex | null | null | YerPhI-99-11 | hep-ph | null | It is investigated the stimulated radiation which arises when the density and
energy of the beam of relativistic particles channeled in microscopic
crystallic undulators (CU) obtained by the application of transverse ultrasonic
(US) oscillations to single crystals, exceed certain values. For positron beams
expected at future linear colliders and real CU it is given the results of
numerical calculations for spontaneous and stimulated radiation.
| [
{
"created": "Thu, 17 Jun 1999 06:14:34 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Avakian",
"R. O.",
""
],
[
"Gevorgian",
"L. A.",
""
],
[
"Ispirian",
"K. A.",
""
],
[
"Ispirian",
"R. K.",
""
]
] | It is investigated the stimulated radiation which arises when the density and energy of the beam of relativistic particles channeled in microscopic crystallic undulators (CU) obtained by the application of transverse ultrasonic (US) oscillations to single crystals, exceed certain values. For positron beams expected at future linear colliders and real CU it is given the results of numerical calculations for spontaneous and stimulated radiation. |
0907.1979 | Mauricio Bustamante | J. L. Bazo Alba (1), M. Bustamante (1), A. M. Gago (1), O. G. Miranda
(2) ((1) Lima, Pont. U. Catolica, (2) Cinvestav, Ipn) | High energy astrophysical neutrino flux and modified dispersion
relations | Accepted for publication in the Int. J. Mod. Phys. A -- Typo in
online version of abstract corrected | Int.J.Mod.Phys.A24:5819-5829,2009 | 10.1142/S0217751X09047429 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the interest in searches for violation of CPT invariance, we
study its possible effects in the flavour ratios of high-energy neutrinos
coming from cosmic accelerators. In particular, we focus on the effect of an
energy independent new physics contribution to the neutrino flavour oscillation
phase and explore whether it is observable in future detectors. Such a
contribution could be related not only to CPT violation but also to a
nonuniversal coupling of neutrinos to a torsion field. We conclude that this
extra phase contribution only becomes observable, in the best case, at energies
greater than 10^{16.5} GeV, which is about five orders of magnitude higher than
the most energetic cosmological neutrinos to be detected in the near future.
Therefore, if these effects are present only in the oscillation phase, they are
going to be unobservable, unless a new mechanism or source capable to produce
neutrinos of such energy were detected.
| [
{
"created": "Sat, 11 Jul 2009 17:45:17 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Jul 2009 22:57:21 GMT",
"version": "v2"
}
] | 2010-01-06 | [
[
"Alba",
"J. L. Bazo",
"",
"Lima, Pont. U. Catolica"
],
[
"Bustamante",
"M.",
"",
"Lima, Pont. U. Catolica"
],
[
"Gago",
"A. M.",
"",
"Lima, Pont. U. Catolica"
],
[
"Miranda",
"O. G.",
"",
"Cinvestav, Ipn"
]
] | Motivated by the interest in searches for violation of CPT invariance, we study its possible effects in the flavour ratios of high-energy neutrinos coming from cosmic accelerators. In particular, we focus on the effect of an energy independent new physics contribution to the neutrino flavour oscillation phase and explore whether it is observable in future detectors. Such a contribution could be related not only to CPT violation but also to a nonuniversal coupling of neutrinos to a torsion field. We conclude that this extra phase contribution only becomes observable, in the best case, at energies greater than 10^{16.5} GeV, which is about five orders of magnitude higher than the most energetic cosmological neutrinos to be detected in the near future. Therefore, if these effects are present only in the oscillation phase, they are going to be unobservable, unless a new mechanism or source capable to produce neutrinos of such energy were detected. |
1308.6779 | Alejandro Celis | Alejandro Celis | Effects of a charged Higgs boson in $B \rightarrow D^{(*)} \tau \nu$
decays | 6 pages, 1 figure and 2 tables; 2013 EPS Conference Proceedings. v2:
minor changes and references added | null | null | IFIC/13-59, FTUV/13-0830 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk I consider the current status of $B \rightarrow D^{(*)} \tau
\nu$ decays in the context of two-Higgs-doublet models. The BaBar collaboration
has reported an excess in semileptonic $b \rightarrow c \tau \nu$ transitions
that has gathered recent interest as a possible signature of new physics. The
sensitivity of these decays to tree-level charged Higgs boson contributions is
discussed, taking into account the constraints from other semileptonic and
leptonic meson decays in which the charged Higgs would enter at the same level.
| [
{
"created": "Fri, 30 Aug 2013 15:51:23 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Sep 2013 18:40:34 GMT",
"version": "v2"
}
] | 2013-09-26 | [
[
"Celis",
"Alejandro",
""
]
] | In this talk I consider the current status of $B \rightarrow D^{(*)} \tau \nu$ decays in the context of two-Higgs-doublet models. The BaBar collaboration has reported an excess in semileptonic $b \rightarrow c \tau \nu$ transitions that has gathered recent interest as a possible signature of new physics. The sensitivity of these decays to tree-level charged Higgs boson contributions is discussed, taking into account the constraints from other semileptonic and leptonic meson decays in which the charged Higgs would enter at the same level. |
0810.3315 | Alexander Bakulev | Alexander P. Bakulev | Thresholds in FAPT: Euclid vs Minkowski | 14 pages, 2 tables, 10 figures. Invited talk at the 15th
International Seminar on High Energy Physics "QUARKS-2008", Sergiev Posad,
Russia, 23--29 May, 2008. Referrences are supplemented with HEP-Arxiv numbers | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We give a short introduction to the Analytic Perturbation Theory (APT) in
QCD, describe its problems and suggest as a tool for their resolution the
Fractional APT (FAPT). We also describe shortly how to treat heavy-quark
thresholds in FAPT. As an applications of this technique we discuss (i) the
pion form factor calculation in the Euclidean FAPT and (ii) the Higgs boson
decay $H^0\to b\bar{b}$ in Minkowskian FAPT. We conclude with comparison of
both approaches, Euclidean and Minkowskian FAPT.
| [
{
"created": "Sat, 18 Oct 2008 13:24:54 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Oct 2008 16:04:59 GMT",
"version": "v2"
}
] | 2008-10-21 | [
[
"Bakulev",
"Alexander P.",
""
]
] | We give a short introduction to the Analytic Perturbation Theory (APT) in QCD, describe its problems and suggest as a tool for their resolution the Fractional APT (FAPT). We also describe shortly how to treat heavy-quark thresholds in FAPT. As an applications of this technique we discuss (i) the pion form factor calculation in the Euclidean FAPT and (ii) the Higgs boson decay $H^0\to b\bar{b}$ in Minkowskian FAPT. We conclude with comparison of both approaches, Euclidean and Minkowskian FAPT. |
1806.01876 | Anirban Biswas | Anirban Biswas, Debasish Borah, Dibyendu Nanda | When Freeze-out Precedes Freeze-in: Sub-TeV Fermion Triplet Dark Matter
with Radiative Neutrino Mass | 29 pages, 10 figures, few minor changes in the text, version
published in JCAP | JCAP09(2018)014 | 10.1088/1475-7516/2018/09/014 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a minimal predictive scenario for dark matter and radiative
neutrino mass where the relic abundance of dark matter is generated from a
hybrid setup comprising of both thermal freeze-out as well as non-thermal
freeze-in mechanisms. Considering three copies of fermion triplets and one
scalar doublet, odd under an unbroken $\mathbb{Z}_2$ symmetry, to be
responsible for radiative origin of neutrino mass, we consider the lightest
fermion triplet as a dark matter candidate which remains under-abundant in the
sub-TeV regime from usual thermal freeze-out. Late decay of the
$\mathbb{Z}_2$-odd scalar doublet into dark matter serves as the non-thermal
(freeze-in) contribution which not only fills the thermal dark matter deficit,
but also constrains the mother particle's parameter space so that the correct
relic abundance of dark matter is generated. Apart from showing interesting
differences from the purely freeze-out and purely freeze-in dark matter
scenarios, the model remains testable through disappearing charge track
signatures at colliders, observable direct and indirect detection rates for
dark matter and prediction of almost vanishing lightest neutrino mass.
| [
{
"created": "Tue, 5 Jun 2018 18:13:47 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Sep 2018 15:49:19 GMT",
"version": "v2"
}
] | 2018-09-11 | [
[
"Biswas",
"Anirban",
""
],
[
"Borah",
"Debasish",
""
],
[
"Nanda",
"Dibyendu",
""
]
] | We propose a minimal predictive scenario for dark matter and radiative neutrino mass where the relic abundance of dark matter is generated from a hybrid setup comprising of both thermal freeze-out as well as non-thermal freeze-in mechanisms. Considering three copies of fermion triplets and one scalar doublet, odd under an unbroken $\mathbb{Z}_2$ symmetry, to be responsible for radiative origin of neutrino mass, we consider the lightest fermion triplet as a dark matter candidate which remains under-abundant in the sub-TeV regime from usual thermal freeze-out. Late decay of the $\mathbb{Z}_2$-odd scalar doublet into dark matter serves as the non-thermal (freeze-in) contribution which not only fills the thermal dark matter deficit, but also constrains the mother particle's parameter space so that the correct relic abundance of dark matter is generated. Apart from showing interesting differences from the purely freeze-out and purely freeze-in dark matter scenarios, the model remains testable through disappearing charge track signatures at colliders, observable direct and indirect detection rates for dark matter and prediction of almost vanishing lightest neutrino mass. |
hep-ph/0110155 | Ansgar Denner | Ansgar Denner | Electroweak Radiative Corrections at High Energies | 6 pages, LaTeX, JHEP style, talk given at the International
Europhysics Conference on High Energy Physics, Budapest, Hungary, July 12-18,
2001 | null | null | null | hep-ph | null | For energies far above the electroweak scale, large electroweak radiative
corrections occur that grow logarithmically with energy and can easily reach
several tens of per cent in the TeV range. Recent work on these corrections is
reviewed.
| [
{
"created": "Thu, 11 Oct 2001 16:32:27 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Denner",
"Ansgar",
""
]
] | For energies far above the electroweak scale, large electroweak radiative corrections occur that grow logarithmically with energy and can easily reach several tens of per cent in the TeV range. Recent work on these corrections is reviewed. |
1903.06884 | Manjit Kaur Dr. | Aayushi Singla, M. Kaur | Multiplicity moments of shifted Gompertz distribution in $e^{+}e^{-}$,
$p\bar{p}$ and $pp$ collisions at high energies | 10 pages, 11 figures, 3 tables | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In continuation of our earlier work, in which we analysed the charged
particle multiplicities in leptonic and hadronic interactions at different
center of mass energies in full phase space as well as in restricted phase
space with the shifted Gompertz distribution, a detailed analysis of the
normalized and factorial moments is reported here. A two-component model in
which probability distribution function is obtained from the superposition of
two shifted Gompertz distributions introduced in our earlier work has also been
used for the analysis. This is the first analysis of the moments with the
shifted Gompertz distribution. Analysis has also been done to predict the
moments of multiplicity distribution for the electron-positron collisions at
c.m. energy of 500 GeV at a future Collider.
| [
{
"created": "Sat, 16 Mar 2019 06:02:24 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Sep 2019 10:46:11 GMT",
"version": "v2"
}
] | 2019-09-12 | [
[
"Singla",
"Aayushi",
""
],
[
"Kaur",
"M.",
""
]
] | In continuation of our earlier work, in which we analysed the charged particle multiplicities in leptonic and hadronic interactions at different center of mass energies in full phase space as well as in restricted phase space with the shifted Gompertz distribution, a detailed analysis of the normalized and factorial moments is reported here. A two-component model in which probability distribution function is obtained from the superposition of two shifted Gompertz distributions introduced in our earlier work has also been used for the analysis. This is the first analysis of the moments with the shifted Gompertz distribution. Analysis has also been done to predict the moments of multiplicity distribution for the electron-positron collisions at c.m. energy of 500 GeV at a future Collider. |
1812.06692 | Mattia Dalla Brida | Mattia Dalla Brida (on behalf of the ALPHA Collaboration) | Precision Determination of $\alpha_s$ from Lattice QCD | 14 pages, 4 figures. Contribution from the "Selected Papers from the
7th International Conference on New Frontiers in Physics (ICNFP 2018)" | Universe 2018, 4(12), 148 | 10.3390/universe4120148 | null | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an overview of the recent lattice determination of the QCD
coupling $\alpha_s$ by the ALPHA Collaboration. The computation is based on the
non-perturbative determination of the $\Lambda$-parameter of $N_{\rm f}=3$ QCD,
and the perturbative matching of the $N_{\rm f}=3$ and $N_{\rm f}=5$ theories.
The final result: $\alpha_s(m_Z)=0.11852(84)$, reaches sub-percent accuracy.
| [
{
"created": "Mon, 17 Dec 2018 10:56:57 GMT",
"version": "v1"
}
] | 2018-12-18 | [
[
"Brida",
"Mattia Dalla",
"",
"on behalf of the ALPHA Collaboration"
]
] | We present an overview of the recent lattice determination of the QCD coupling $\alpha_s$ by the ALPHA Collaboration. The computation is based on the non-perturbative determination of the $\Lambda$-parameter of $N_{\rm f}=3$ QCD, and the perturbative matching of the $N_{\rm f}=3$ and $N_{\rm f}=5$ theories. The final result: $\alpha_s(m_Z)=0.11852(84)$, reaches sub-percent accuracy. |
2406.03331 | Henrique Brito C\^amara | J. R. Rocha, H. B. C\^amara, R. G. Felipe, F. R. Joaquim | Minimal U(1) two-Higgs-doublet models for quark and lepton flavour | 32 LaTeX pages; 7 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the context of the 2HDM, and assuming that neutrinos acquire masses via
the Weinberg operator, we perform a systematic analysis to determine the
minimal quark and lepton flavour patterns, compatible with masses, mixing and
CP violation data, realisable by Abelian symmetries. We determine four minimal
models for quarks, where the number of independent parameters matches the
number of observables. For the lepton sector, three minimal predictive models
are identified. Namely, we find scenarios with a preference for the upper/lower
octant of the $\theta_{23}$ atmospheric mixing angle, that exhibit lower bounds
on the lightest neutrino masses currently probed by cosmology and testable at
future neutrinoless double beta decay experiments, even for a normally-ordered
neutrino masses. We investigate the phenomenology of each model taking into
account all relevant theoretical, electroweak precision observables, scalar
sector constraints, as well as stringent quark flavour processes such as
$\overline{B} \rightarrow X_s \gamma$, $B_s \rightarrow \mu^- \mu^+$ and meson
oscillations, and the charged lepton flavour-violating decays $e_\alpha^{-}
\rightarrow e_\beta^{-} e_\gamma^{+} e_\delta^{-}$ and $e_\alpha \rightarrow
e_\beta \gamma$. We show that, in some cases, Abelian flavour symmetries
provide a natural framework to suppress flavour-changing neutral couplings and
lead to scenarios featuring heavy neutral/charged scalar masses below the TeV
scale within the reach of current experiments.
| [
{
"created": "Wed, 5 Jun 2024 14:45:00 GMT",
"version": "v1"
}
] | 2024-06-06 | [
[
"Rocha",
"J. R.",
""
],
[
"Câmara",
"H. B.",
""
],
[
"Felipe",
"R. G.",
""
],
[
"Joaquim",
"F. R.",
""
]
] | In the context of the 2HDM, and assuming that neutrinos acquire masses via the Weinberg operator, we perform a systematic analysis to determine the minimal quark and lepton flavour patterns, compatible with masses, mixing and CP violation data, realisable by Abelian symmetries. We determine four minimal models for quarks, where the number of independent parameters matches the number of observables. For the lepton sector, three minimal predictive models are identified. Namely, we find scenarios with a preference for the upper/lower octant of the $\theta_{23}$ atmospheric mixing angle, that exhibit lower bounds on the lightest neutrino masses currently probed by cosmology and testable at future neutrinoless double beta decay experiments, even for a normally-ordered neutrino masses. We investigate the phenomenology of each model taking into account all relevant theoretical, electroweak precision observables, scalar sector constraints, as well as stringent quark flavour processes such as $\overline{B} \rightarrow X_s \gamma$, $B_s \rightarrow \mu^- \mu^+$ and meson oscillations, and the charged lepton flavour-violating decays $e_\alpha^{-} \rightarrow e_\beta^{-} e_\gamma^{+} e_\delta^{-}$ and $e_\alpha \rightarrow e_\beta \gamma$. We show that, in some cases, Abelian flavour symmetries provide a natural framework to suppress flavour-changing neutral couplings and lead to scenarios featuring heavy neutral/charged scalar masses below the TeV scale within the reach of current experiments. |
0908.0395 | Tatsuo Kobayashi | Kang-Sin Choi, Tatsuo Kobayashi, Ryosuke Maruyama, Masaki Murata,
Yuichiro Nakai, Hiroshi Ohki, Manabu Sakai | E6,7,8 Magnetized Extra Dimensional Models | 17 pages, 1 figure | Eur.Phys.J.C67:273-282,2010 | 10.1140/epjc/s10052-010-1275-9 | KUNS-2223, YITP-09-50 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study 10D super Yang-Mills theory with the gauge groups $E_6$, $E_7$ and
$E_8$. We consider the torus/orbifold compacfitication with magnetic fluxes and
Wilson lines. They lead to 4D interesting models with three families of quarks
and leptons, whose profiles in extra dimensions are quasi-localized because of
magnetic fluxes.
| [
{
"created": "Tue, 4 Aug 2009 08:24:58 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Feb 2010 02:23:50 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Choi",
"Kang-Sin",
""
],
[
"Kobayashi",
"Tatsuo",
""
],
[
"Maruyama",
"Ryosuke",
""
],
[
"Murata",
"Masaki",
""
],
[
"Nakai",
"Yuichiro",
""
],
[
"Ohki",
"Hiroshi",
""
],
[
"Sakai",
"Manabu",
""
]
] | We study 10D super Yang-Mills theory with the gauge groups $E_6$, $E_7$ and $E_8$. We consider the torus/orbifold compacfitication with magnetic fluxes and Wilson lines. They lead to 4D interesting models with three families of quarks and leptons, whose profiles in extra dimensions are quasi-localized because of magnetic fluxes. |
1506.02148 | Farvah Mahmoudi | A. Arbey, M. Battaglia, F. Mahmoudi | Monojet Searches for MSSM Simplified Models | 9 pages, 8 figures | Phys. Rev. D 94, 055015 (2016) | 10.1103/PhysRevD.94.055015 | CERN-PH-TH/2015-133 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore the implications of monojet searches at hadron colliders in the
minimal supersymmetric extension of the Standard Model (MSSM). To quantify the
impact of monojet searches, we consider simplified MSSM scenarios with
neutralino dark matter. The monojet results of the LHC Run 1 are reinterpreted
in the context of several MSSM simplified scenarios, and the complementarity
with direct supersymmetry search results is highlighted. We also investigate
the reach of monojet searches for the Run 2, as well as for future higher
energy hadron colliders.
| [
{
"created": "Sat, 6 Jun 2015 13:02:21 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Sep 2016 20:00:48 GMT",
"version": "v2"
}
] | 2016-09-21 | [
[
"Arbey",
"A.",
""
],
[
"Battaglia",
"M.",
""
],
[
"Mahmoudi",
"F.",
""
]
] | We explore the implications of monojet searches at hadron colliders in the minimal supersymmetric extension of the Standard Model (MSSM). To quantify the impact of monojet searches, we consider simplified MSSM scenarios with neutralino dark matter. The monojet results of the LHC Run 1 are reinterpreted in the context of several MSSM simplified scenarios, and the complementarity with direct supersymmetry search results is highlighted. We also investigate the reach of monojet searches for the Run 2, as well as for future higher energy hadron colliders. |
hep-ph/9812475 | Ferruccio Feruglio | Guido Altarelli and Ferruccio Feruglio | A Simple Grand Unification View of Neutrino Mixing and Fermion Mass
Matrices | 12 pages, LATEX, no figures; discussion added on the just-so
solution; version to appear on Phys. Lett. B | Phys.Lett.B451:388-396,1999 | 10.1016/S0370-2693(99)00208-7 | CERN-TH/98-410, DFPD-98/TH/52 | hep-ph | null | Assuming three light neutrinos and the see-saw mechanism we present a
semiquantitative model of fermion masses based on (SUSY) SU(5) and abelian
horizontal charges. A good description of the observed pattern of quark and
lepton masses is obtained. For neutrinos we naturally obtain widely split
masses and large atmospheric neutrino mixing as a consequence of SU(5)-related
asymmetric mass matrices for d quarks and charged leptons.
| [
{
"created": "Tue, 22 Dec 1998 14:32:47 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Mar 1999 09:20:27 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Altarelli",
"Guido",
""
],
[
"Feruglio",
"Ferruccio",
""
]
] | Assuming three light neutrinos and the see-saw mechanism we present a semiquantitative model of fermion masses based on (SUSY) SU(5) and abelian horizontal charges. A good description of the observed pattern of quark and lepton masses is obtained. For neutrinos we naturally obtain widely split masses and large atmospheric neutrino mixing as a consequence of SU(5)-related asymmetric mass matrices for d quarks and charged leptons. |
1504.05187 | Adam Coogan | Adam Coogan, Stefano Profumo, William Shepherd | Monochromatic Gamma Rays from Dark Matter Annihilation to Leptons | 21 pages plus appendices, 7 figures. v2: added experimental
constraints from CMB and Fermi, expanded and reorganized discussion
throughout. Accepted by JHEP | JHEP 1508 (2015) 074 | 10.1007/JHEP08(2015)074 | SCIPP 15/06 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the relation between the annihilation of dark matter (DM)
particles into lepton pairs and into 2-body final states including one or two
photons. We parametrize the DM interactions with leptons in terms of contact
interactions, and calculate the loop-level annihilation into monochromatic
gamma rays, specifically computing the ratio of the DM annihilation cross
sections into two gamma rays versus lepton pairs. While the loop-level
processes are generically suppressed in comparison with the tree-level
annihilation into leptons, we find that some choices for the mediator spin and
coupling structure lead to large branching fractions into gamma-ray lines. This
result has implications for a dark matter contribution to the AMS-02 positron
excess. We also explore the possibility of mediators which are charged under a
dark symmetry and find that, for these loop-level processes, an effective field
theory description is accurate for DM masses up to about half the mediator
mass.
| [
{
"created": "Mon, 20 Apr 2015 20:00:39 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jul 2015 18:58:07 GMT",
"version": "v2"
}
] | 2015-09-03 | [
[
"Coogan",
"Adam",
""
],
[
"Profumo",
"Stefano",
""
],
[
"Shepherd",
"William",
""
]
] | We investigate the relation between the annihilation of dark matter (DM) particles into lepton pairs and into 2-body final states including one or two photons. We parametrize the DM interactions with leptons in terms of contact interactions, and calculate the loop-level annihilation into monochromatic gamma rays, specifically computing the ratio of the DM annihilation cross sections into two gamma rays versus lepton pairs. While the loop-level processes are generically suppressed in comparison with the tree-level annihilation into leptons, we find that some choices for the mediator spin and coupling structure lead to large branching fractions into gamma-ray lines. This result has implications for a dark matter contribution to the AMS-02 positron excess. We also explore the possibility of mediators which are charged under a dark symmetry and find that, for these loop-level processes, an effective field theory description is accurate for DM masses up to about half the mediator mass. |
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