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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2108.13151 | Tim Neidig | Tim Neidig, Kai Gallmeister, Carsten Greiner, Marcus Bleicher,
Volodymyr Vovchenko | Solving the puzzle of high temperature light (anti)-nuclei production in
ultra-relativistic heavy ion collisions | 6 pages, 5 figures | null | 10.1016/j.physletb.2022.136891 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The creation of loosely bound objects in heavy ion collisions, e.g. light
clusters, near the phase transition temperature $\left(T_{\rm ch} \approx 155
\, \rm{MeV} \right)$ has been a puzzling observation that seems to be at odds
with Big Bang nucleosynthesis suggesting that deuterons and other clusters are
formed only below a temperature $T\approx 0.1-1 \, \text{MeV}$. We solve this
puzzle by showing that the light cluster abundancies in heavy ion reactions
stay approximately constant from chemical freeze-out to kinetic freeze-out. To
this aim we develop an extensive network of coupled reaction rate equations
including stable hadrons and hadronic resonances to describe the temporal
evolution of the abundancies of light (anti-)(hyper-)nuclei in the late
hadronic environment of an ultrarelativistic heavy ion collision. It is
demonstrated that the chemical equilibration of the light nuclei occurs on a
very short timescale as a consequence of the strong production and dissociation
processes. However, because of the partial chemical equilibrium of the stable
hadrons, including the nucleon feeding from $\Delta$ resonances, the
abundancies of the light nuclei stay nearly constant during the evolution and
cooling of the hadronic phase. This solves the longstanding contradiction
between the thermal fits and the late stage coalescence (and the Big Bang
nucleosynthesis) and explains why the observed light cluster yields are
compatible with both a high chemical production temperature and a late state
emission as modelled by coalescence. We also note in passing that the
abundancies of the light clusters in the present approach are in excellent
agreement with those measured by ALICE at LHC.
| [
{
"created": "Mon, 30 Aug 2021 12:22:46 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Sep 2021 13:19:45 GMT",
"version": "v2"
}
] | 2022-01-12 | [
[
"Neidig",
"Tim",
""
],
[
"Gallmeister",
"Kai",
""
],
[
"Greiner",
"Carsten",
""
],
[
"Bleicher",
"Marcus",
""
],
[
"Vovchenko",
"Volodymyr",
""
]
] | The creation of loosely bound objects in heavy ion collisions, e.g. light clusters, near the phase transition temperature $\left(T_{\rm ch} \approx 155 \, \rm{MeV} \right)$ has been a puzzling observation that seems to be at odds with Big Bang nucleosynthesis suggesting that deuterons and other clusters are formed only below a temperature $T\approx 0.1-1 \, \text{MeV}$. We solve this puzzle by showing that the light cluster abundancies in heavy ion reactions stay approximately constant from chemical freeze-out to kinetic freeze-out. To this aim we develop an extensive network of coupled reaction rate equations including stable hadrons and hadronic resonances to describe the temporal evolution of the abundancies of light (anti-)(hyper-)nuclei in the late hadronic environment of an ultrarelativistic heavy ion collision. It is demonstrated that the chemical equilibration of the light nuclei occurs on a very short timescale as a consequence of the strong production and dissociation processes. However, because of the partial chemical equilibrium of the stable hadrons, including the nucleon feeding from $\Delta$ resonances, the abundancies of the light nuclei stay nearly constant during the evolution and cooling of the hadronic phase. This solves the longstanding contradiction between the thermal fits and the late stage coalescence (and the Big Bang nucleosynthesis) and explains why the observed light cluster yields are compatible with both a high chemical production temperature and a late state emission as modelled by coalescence. We also note in passing that the abundancies of the light clusters in the present approach are in excellent agreement with those measured by ALICE at LHC. |
hep-ph/9802409 | Thorsten Feldmann | T. Feldmann, P. Kroll (Wuppertal Univ.) and B. Stech (Heidelberg
Univ.) | Mixing and Decay Constants of Pseudoscalar Mesons | 14 pages, uses feynmp.sty | Phys. Rev. D 58, 114006 (1998) | 10.1103/PhysRevD.58.114006 | WU B 98-2, HD-THEP-98-5 | hep-ph hep-ex nucl-th | null | We propose a new eta-eta' mixing scheme where we start from the quark flavor
basis and assume that the decay constants in that basis follow the pattern of
particle state mixing. On exploiting the divergences of the axial vector
currents - which embody the axial vector anomaly - all basic parameters are
fixed to first order of flavor symmetry breaking. That approach naturally leads
to a mass matrix, quadratic in the masses, with specified elements. We also
test our mixing scheme against experiment and determine corrections to the
first order values of the basic parameters from phenomenology. Finally, we
generalize the mixing scheme to include the eta(c). Again the divergences of
the axial vector currents fix the mass matrix and, hence, mixing angles and the
charm content of the eta and eta'.
| [
{
"created": "Tue, 24 Feb 1998 14:39:44 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jul 1998 13:44:16 GMT",
"version": "v2"
}
] | 2016-08-25 | [
[
"Feldmann",
"T.",
"",
"Wuppertal Univ."
],
[
"Kroll",
"P.",
"",
"Wuppertal Univ."
],
[
"Stech",
"B.",
"",
"Heidelberg\n Univ."
]
] | We propose a new eta-eta' mixing scheme where we start from the quark flavor basis and assume that the decay constants in that basis follow the pattern of particle state mixing. On exploiting the divergences of the axial vector currents - which embody the axial vector anomaly - all basic parameters are fixed to first order of flavor symmetry breaking. That approach naturally leads to a mass matrix, quadratic in the masses, with specified elements. We also test our mixing scheme against experiment and determine corrections to the first order values of the basic parameters from phenomenology. Finally, we generalize the mixing scheme to include the eta(c). Again the divergences of the axial vector currents fix the mass matrix and, hence, mixing angles and the charm content of the eta and eta'. |
hep-ph/0606206 | Utpal Sarkar | Utpal Sarkar | Anomaly for Model Building | 9 pages | Int.J.Mod.Phys.A22:931-936,2007 | 10.1142/S0217751X07034969 | null | hep-ph | null | A simple algorithm to calculate the group theory factor entering in anomalies
at four and six dimensions for SU(N) and SO(N) groups in terms of the Casimir
invariants of their subgroups is presented. Explicit examples of some of the
lower dimensional representations of $SU(n), n \leq 5$ and SO(10) groups are
presented, which could be used for model building in four and six dimensions.
| [
{
"created": "Mon, 19 Jun 2006 18:39:17 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Sarkar",
"Utpal",
""
]
] | A simple algorithm to calculate the group theory factor entering in anomalies at four and six dimensions for SU(N) and SO(N) groups in terms of the Casimir invariants of their subgroups is presented. Explicit examples of some of the lower dimensional representations of $SU(n), n \leq 5$ and SO(10) groups are presented, which could be used for model building in four and six dimensions. |
hep-ph/0408087 | Daniele Dominici | Daniele Dominici | Invisible Higgs in large extra dimension models | 4 pages, 3 figures, talk given at the International Linear Collider
Workshop, Paris, France, April 2004 | null | null | null | hep-ph | null | In large extra dimension models the presence of an interaction between the
Ricci scalar curvature and the Higgs doublet of the Standard Model can give
rise to an invisible decay of the Higgs to Kaluza Klein graviscalars. The
corresponding invisible width can cause a suppression of the LHC rates of a
light Higgs in the visible channels below 5 sigma in some regions of the
parameter space of the model. However in such regions the Higgs can be
discovered through its invisible decay. The combination of the measurements
done at the LHC and the LC can determine to some accuracy the parameters of the
model.
| [
{
"created": "Fri, 6 Aug 2004 11:14:33 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dominici",
"Daniele",
""
]
] | In large extra dimension models the presence of an interaction between the Ricci scalar curvature and the Higgs doublet of the Standard Model can give rise to an invisible decay of the Higgs to Kaluza Klein graviscalars. The corresponding invisible width can cause a suppression of the LHC rates of a light Higgs in the visible channels below 5 sigma in some regions of the parameter space of the model. However in such regions the Higgs can be discovered through its invisible decay. The combination of the measurements done at the LHC and the LC can determine to some accuracy the parameters of the model. |
1911.12055 | Nahid Vasim | Nahid Vasim and Raktim Abir | Infrared renormalon effects in color dipole TMD PDF at small-$x$ | null | null | null | null | hep-ph hep-th nucl-th | http://creativecommons.org/licenses/by-sa/4.0/ | The uncertainties from the infrared renormalons in the (color dipole) gluon
distribution is estimated. It is shown that non-linear saturation effects at
small-$x$ shift the first IR pole at the Borel plane from $2/\beta_2$ to
$1/\beta_2$. As a consequence the estimated uncertainty is found to be ${\cal
O}\left(\Lambda_{\rm QCD}^2\right)$ instead of ${\cal O}\left(\Lambda_{\rm
QCD}^4\right)$.
| [
{
"created": "Wed, 27 Nov 2019 10:06:21 GMT",
"version": "v1"
}
] | 2019-11-28 | [
[
"Vasim",
"Nahid",
""
],
[
"Abir",
"Raktim",
""
]
] | The uncertainties from the infrared renormalons in the (color dipole) gluon distribution is estimated. It is shown that non-linear saturation effects at small-$x$ shift the first IR pole at the Borel plane from $2/\beta_2$ to $1/\beta_2$. As a consequence the estimated uncertainty is found to be ${\cal O}\left(\Lambda_{\rm QCD}^2\right)$ instead of ${\cal O}\left(\Lambda_{\rm QCD}^4\right)$. |
0910.3125 | Ingrid Kraus | I. Kraus, J. Cleymans, H. Oeschler, and K. Redlich | Particle production in p-p collisions at sqrt(s) = 17 GeV within the
statistical model | 6 pages, 3 figures, submitted to Phys. Rev. C | Phys.Rev.C81:024903,2010 | 10.1103/PhysRevC.81.024903 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A thermal-model analysis of particle production of p-p collisions at sqrt(s)
= 17 GeV using the latest available data is presented. The sensitivity of model
parameters on data selections and model assumptions is studied. The system-size
dependence of thermal parameters and recent differences in the statistical
model analysis of p-p collisions at the super proton synchrotron (SPS) are
discussed. It is shown that the temperature and strangeness undersaturation
factor depend strongly on kaon yields which at present are still not well known
experimentally. It is conclude, that within the presently available data at the
SPS it is rather unlikely that the temperature in p-p collisions exceeds
significantly that expected in central collisions of heavy ions at the same
energy.
| [
{
"created": "Fri, 16 Oct 2009 14:04:16 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Kraus",
"I.",
""
],
[
"Cleymans",
"J.",
""
],
[
"Oeschler",
"H.",
""
],
[
"Redlich",
"K.",
""
]
] | A thermal-model analysis of particle production of p-p collisions at sqrt(s) = 17 GeV using the latest available data is presented. The sensitivity of model parameters on data selections and model assumptions is studied. The system-size dependence of thermal parameters and recent differences in the statistical model analysis of p-p collisions at the super proton synchrotron (SPS) are discussed. It is shown that the temperature and strangeness undersaturation factor depend strongly on kaon yields which at present are still not well known experimentally. It is conclude, that within the presently available data at the SPS it is rather unlikely that the temperature in p-p collisions exceeds significantly that expected in central collisions of heavy ions at the same energy. |
1502.05044 | Matthew Low | Asher Berlin, Tongyan Lin, Matthew Low, and Lian-Tao Wang | Neutralinos in Vector Boson Fusion at High Energy Colliders | v2: 7 pages, 5 figures, 3 tables; added references and updated to
published version | Phys. Rev. D 91, 115002 (2015) | 10.1103/PhysRevD.91.115002 | EFI-15-3 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Discovering dark matter at high energy colliders continues to be a compelling
and well-motivated possibility. Weakly interacting massive particles are a
particularly interesting class in which the dark matter particles interact with
the standard model weak gauge bosons. Neutralinos are a prototypical example
that arise in supersymmetric models. In the limit where all other superpartners
are decoupled, it is known that for relic density motivated masses, the rates
for neutralinos are too small to be discovered at the Large Hadron Collider
(LHC), but that they may be large enough for a 100 TeV collider to observe. In
this work we perform a careful study in the vector boson fusion channel for
pure winos and pure higgsinos. We find that given a systematic uncertainty of
1% (5%), with 3000 fb$^{-1}$, the LHC is sensitive to winos of 240 GeV (125
GeV) and higgsinos of 125 GeV (55 GeV). A future 100 TeV collider would be
sensitive to winos of 1.1 TeV (750 GeV) and higgsinos of 530 GeV (180 GeV) with
a 1% (5%) uncertainty, also with 3000 fb$^{-1}$.
| [
{
"created": "Tue, 17 Feb 2015 21:00:05 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Jun 2015 18:30:08 GMT",
"version": "v2"
}
] | 2015-06-18 | [
[
"Berlin",
"Asher",
""
],
[
"Lin",
"Tongyan",
""
],
[
"Low",
"Matthew",
""
],
[
"Wang",
"Lian-Tao",
""
]
] | Discovering dark matter at high energy colliders continues to be a compelling and well-motivated possibility. Weakly interacting massive particles are a particularly interesting class in which the dark matter particles interact with the standard model weak gauge bosons. Neutralinos are a prototypical example that arise in supersymmetric models. In the limit where all other superpartners are decoupled, it is known that for relic density motivated masses, the rates for neutralinos are too small to be discovered at the Large Hadron Collider (LHC), but that they may be large enough for a 100 TeV collider to observe. In this work we perform a careful study in the vector boson fusion channel for pure winos and pure higgsinos. We find that given a systematic uncertainty of 1% (5%), with 3000 fb$^{-1}$, the LHC is sensitive to winos of 240 GeV (125 GeV) and higgsinos of 125 GeV (55 GeV). A future 100 TeV collider would be sensitive to winos of 1.1 TeV (750 GeV) and higgsinos of 530 GeV (180 GeV) with a 1% (5%) uncertainty, also with 3000 fb$^{-1}$. |
2210.06838 | Stefano Di Noi | Stefano Di Noi, Luca Silvestrini | $\texttt{RGESolver}$ : a $\texttt{C++}$ library to perform
Renormalization Group evolution in the Standard Model Effective Theory | null | Eur.Phys.J.C 83 (2023) 3, 200 | 10.1140/epjc/s10052-023-11189-4 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Renormalization group evolution above the electroweak scale is a crucial
ingredient in the phenomenology of the Standard Model Effective Theory. The
RGESolver open-source C++ library performs the evolution at leading order for
dimension-six operators in the most general flavour scenario (assuming lepton
and baryon number conservation). Given its efficiency, RGESolver can be used to
include the effects of renormalization group evolution in extensive
phenomenological analyses in the framework of the Standard Model Effective
Theory.
| [
{
"created": "Thu, 13 Oct 2022 08:44:34 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Jun 2023 07:48:43 GMT",
"version": "v2"
}
] | 2023-06-07 | [
[
"Di Noi",
"Stefano",
""
],
[
"Silvestrini",
"Luca",
""
]
] | Renormalization group evolution above the electroweak scale is a crucial ingredient in the phenomenology of the Standard Model Effective Theory. The RGESolver open-source C++ library performs the evolution at leading order for dimension-six operators in the most general flavour scenario (assuming lepton and baryon number conservation). Given its efficiency, RGESolver can be used to include the effects of renormalization group evolution in extensive phenomenological analyses in the framework of the Standard Model Effective Theory. |
hep-ph/0510209 | A. Yu. Ignatiev | A.Yu.Ignatiev and V.A.Kuzmin | Neutrino statistics and non-standard commutation relations | 11 pages, RevTeX4 | Phys.Lett. A359 (2006) 26-30 | 10.1016/j.physleta.2006.05.083 | null | hep-ph | null | Recently it was suggested that the neutrino may violate the Pauli exclusion
Principle (PEP). This renews interest in the systematic search for bilinear
commutation relations that could describe deviations from PEP. In the context
of this search we prove a no-go theorem which forbids a finite occupancy limit
for an arbitrary system with a bilinear commutation relation. In other words,
either the upper limit on the occupancy number is 1 (the ordinary fermionic
case) or there is no upper limit at all. Some examples of the latter class
include the usual Bose statistics, as well as non-standard quon statistics and
infinite statistics.
| [
{
"created": "Sun, 16 Oct 2005 10:42:53 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Ignatiev",
"A. Yu.",
""
],
[
"Kuzmin",
"V. A.",
""
]
] | Recently it was suggested that the neutrino may violate the Pauli exclusion Principle (PEP). This renews interest in the systematic search for bilinear commutation relations that could describe deviations from PEP. In the context of this search we prove a no-go theorem which forbids a finite occupancy limit for an arbitrary system with a bilinear commutation relation. In other words, either the upper limit on the occupancy number is 1 (the ordinary fermionic case) or there is no upper limit at all. Some examples of the latter class include the usual Bose statistics, as well as non-standard quon statistics and infinite statistics. |
1011.3735 | Thomas Konstandin | Thomas Konstandin and Jose M. No | Hydrodynamic obstruction to bubble expansion | 18 pages, 4 figures; comments and reference added, published version | JCAP 1102:008,2011 | 10.1088/1475-7516/2011/02/008 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss a hydrodynamic obstruction to bubble wall acceleration during a
cosmological first-order phase transition. The obstruction results from the
heating of the plasma in the compression wave in front of the phase transition
boundary. We provide a simple criterion for the occurrence of the obstruction
at subsonic bubble wall velocity in terms of the critical temperature, the
phase transition temperature, and the latent heat of the model under
consideration. The criterion serves as a sufficient condition of subsonic
bubble wall velocities as required by electroweak baryogenesis.
| [
{
"created": "Tue, 16 Nov 2010 15:42:20 GMT",
"version": "v1"
},
{
"created": "Wed, 23 Feb 2011 13:31:07 GMT",
"version": "v2"
}
] | 2011-03-18 | [
[
"Konstandin",
"Thomas",
""
],
[
"No",
"Jose M.",
""
]
] | We discuss a hydrodynamic obstruction to bubble wall acceleration during a cosmological first-order phase transition. The obstruction results from the heating of the plasma in the compression wave in front of the phase transition boundary. We provide a simple criterion for the occurrence of the obstruction at subsonic bubble wall velocity in terms of the critical temperature, the phase transition temperature, and the latent heat of the model under consideration. The criterion serves as a sufficient condition of subsonic bubble wall velocities as required by electroweak baryogenesis. |
hep-ph/0009044 | John Bahcall | John N. Bahcall | Astrophysical neutrinos: 20th Century and Beyond | IUPAP Centennial Lecture, Neutrino 2000; related information:
http://www.sns.ias.edu/~jnb | Nucl.Phys.Proc.Suppl. 91 (2001) 9-17; Int.J.Mod.Phys. A16 (2000)
4955-4968 | 10.1142/S0217751X01005948 | null | hep-ph astro-ph hep-ex nucl-ex nucl-th physics.hist-ph | null | I summarize the first four decades of solar neutrino research and suggest
what may be possible to learn with extragalactic neutrinos and with solar
neutrinos in the next decade.
| [
{
"created": "Tue, 5 Sep 2000 17:31:38 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Bahcall",
"John N.",
""
]
] | I summarize the first four decades of solar neutrino research and suggest what may be possible to learn with extragalactic neutrinos and with solar neutrinos in the next decade. |
0805.3911 | Thorsten Ewerth | Thorsten Ewerth (Turin U. & INFN, Turin) | Fermionic corrections to the interference of the electro- and
chromomagnetic dipole operators in anti-B --> X(s) gamma at O(alpha(s)**2) | 13 pages, uses axodraw.sty; minor changes, matches published version | Phys.Lett.B669:167-172,2008 | 10.1016/j.physletb.2008.09.045 | null | hep-ph | http://creativecommons.org/licenses/by-nc-sa/3.0/ | We calculate the virtual and bremsstrahlung fermionic corrections due to the
interference of the electro- and chromomagnetic dipole operators in the
inclusive \bar{B}\to X_s\gamma decay at O(\alpha_s^2) and present analytical
results for both the total decay rate and the photon energy spectrum.
| [
{
"created": "Mon, 26 May 2008 19:51:49 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Oct 2008 16:07:48 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Ewerth",
"Thorsten",
"",
"Turin U. & INFN, Turin"
]
] | We calculate the virtual and bremsstrahlung fermionic corrections due to the interference of the electro- and chromomagnetic dipole operators in the inclusive \bar{B}\to X_s\gamma decay at O(\alpha_s^2) and present analytical results for both the total decay rate and the photon energy spectrum. |
2007.05913 | Xin Wang | Xin Wang | Dirac neutrino mass models with a modular $S^{}_4$ symmetry | 34 pages, 7 figures, more discussions and references added, to be
published in NPB | null | 10.1016/j.nuclphysb.2020.115247 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we investigate lepton mass spectra, flavor mixing and CP
violation with a modular $S^{}_4$ symmetry under the assumption that neutrinos
are Dirac fermions. We find that the Majorana mass term can be forbidden by
adjusting the weight of the right-handed neutrino superfields. We study the
scenarios where modular forms in the neutrino sector take the lowest
non-trivial weight two, while those in the charged-lepton sector vary from two
to six. The corrections from renormalization-group running effects to our model
have also been discussed in detail. We totally obtain twelve different classes
of models and find that ten of them can accommodate current neutrino
oscillation data.
| [
{
"created": "Sun, 12 Jul 2020 05:16:46 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Nov 2020 13:55:20 GMT",
"version": "v2"
}
] | 2020-12-30 | [
[
"Wang",
"Xin",
""
]
] | In this paper, we investigate lepton mass spectra, flavor mixing and CP violation with a modular $S^{}_4$ symmetry under the assumption that neutrinos are Dirac fermions. We find that the Majorana mass term can be forbidden by adjusting the weight of the right-handed neutrino superfields. We study the scenarios where modular forms in the neutrino sector take the lowest non-trivial weight two, while those in the charged-lepton sector vary from two to six. The corrections from renormalization-group running effects to our model have also been discussed in detail. We totally obtain twelve different classes of models and find that ten of them can accommodate current neutrino oscillation data. |
1307.1688 | Sukanta Dutta | Sukanta Dutta, Ashok Goyal, Mukesh Kumar and Bruce Mellado | Measuring anomalous $Wtb$ couplings at $e^-p$ collider | 21 pages | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the accuracy with which the lowest order $CP$ conserving anomalous
$Wtb$ couplings in the single top quark production at the proposed large hadron
electron collider (LHeC) can be probed. The one dimensional distribution of
various kinematic observables at the parton level MC and their asymmetries
arising due to the presence of anomalous couplings both in the hadronic and
leptonic $W$ decay is examined. \par We find that at 95 \% C.L. the anomalous
coupling associated with the left handed vector current can be measured at an
accuracy of the order of $\sim 10^{-2}-10^{-3}$, while those associated with
the right handed vector and left as well as right handed tensor currents have
sensitivity at the order of $\sim 10^{-1}-10^{-2}$ for the systematic
uncertainty varying between 10\%-1\% at an integrated luminosity of 100
fb$^{-1}$. A comprehensive analysis of the combined covariance matrix derived
from all one dimensional distributions of kinematical observables is used to
compute the errors in anomalous couplings.
| [
{
"created": "Fri, 5 Jul 2013 18:53:07 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Mar 2014 20:07:35 GMT",
"version": "v2"
},
{
"created": "Mon, 26 Oct 2015 18:41:49 GMT",
"version": "v3"
}
] | 2015-10-27 | [
[
"Dutta",
"Sukanta",
""
],
[
"Goyal",
"Ashok",
""
],
[
"Kumar",
"Mukesh",
""
],
[
"Mellado",
"Bruce",
""
]
] | We study the accuracy with which the lowest order $CP$ conserving anomalous $Wtb$ couplings in the single top quark production at the proposed large hadron electron collider (LHeC) can be probed. The one dimensional distribution of various kinematic observables at the parton level MC and their asymmetries arising due to the presence of anomalous couplings both in the hadronic and leptonic $W$ decay is examined. \par We find that at 95 \% C.L. the anomalous coupling associated with the left handed vector current can be measured at an accuracy of the order of $\sim 10^{-2}-10^{-3}$, while those associated with the right handed vector and left as well as right handed tensor currents have sensitivity at the order of $\sim 10^{-1}-10^{-2}$ for the systematic uncertainty varying between 10\%-1\% at an integrated luminosity of 100 fb$^{-1}$. A comprehensive analysis of the combined covariance matrix derived from all one dimensional distributions of kinematical observables is used to compute the errors in anomalous couplings. |
2002.08051 | Yubing Dong | Yubing Dong, Pengnian Shen, Fei Huang, and Zongye Zhang | Selected strong decays of pentaquark State $P_c(4312)$ in a chiral
constituent quark model | 13 pages, 2 figures, 3 tables | null | 10.1140/epjc/s10052-020-7890-1 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The newly confirmed pentaquark state $P_c(4312)$ has been treated as a weakly
bound $(\Sigma_c\bar{D})$ state by a well-established chiral constituent quark
model and by a dynamical calculation on quark degrees of freedom where the
quark exchange effect is accounted for. The obtained mass $4308$ MeV agrees
with data. In this work, the selected strong decays of the $P_c(4312)$ state
are studied with the obtained wave function. It is shown that the width of the
$\Lambda_c\bar{D}^*$ decay is overwhelmed and the branching ratios of the
$p\,\eta_c$ and $p\,J/\psi$ decays are both less than 1 percentage.
| [
{
"created": "Wed, 19 Feb 2020 08:26:50 GMT",
"version": "v1"
}
] | 2020-05-20 | [
[
"Dong",
"Yubing",
""
],
[
"Shen",
"Pengnian",
""
],
[
"Huang",
"Fei",
""
],
[
"Zhang",
"Zongye",
""
]
] | The newly confirmed pentaquark state $P_c(4312)$ has been treated as a weakly bound $(\Sigma_c\bar{D})$ state by a well-established chiral constituent quark model and by a dynamical calculation on quark degrees of freedom where the quark exchange effect is accounted for. The obtained mass $4308$ MeV agrees with data. In this work, the selected strong decays of the $P_c(4312)$ state are studied with the obtained wave function. It is shown that the width of the $\Lambda_c\bar{D}^*$ decay is overwhelmed and the branching ratios of the $p\,\eta_c$ and $p\,J/\psi$ decays are both less than 1 percentage. |
hep-ph/0506253 | Cailin Farrell | Cailin Farrell, Andre H. Hoang | Effects of the t t-bar threshold in e+e- to t t-bar H | Invited talk at 2005 International Linear Collider Workshop, Stanford
Ca (LCWS05), PSN 0404, 6 pages, Latex, 4 eps figures, 1 table | null | null | MPP-2005-68 | hep-ph | null | In the region where the Higgs energy is large the process e+e- to t t-bar H
is governed by nonrelativistic QCD dynamics and one has to employ effective
theory methods to make first principles QCD predictions. In this talk we use
the effective theory vNRQCD to compute the Higgs energy distribution at
next-to-leading logarithmic approximation. It is shown that the corrections are
particularly important for smaller c.m. energies.
| [
{
"created": "Fri, 24 Jun 2005 16:19:08 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Farrell",
"Cailin",
""
],
[
"Hoang",
"Andre H.",
""
]
] | In the region where the Higgs energy is large the process e+e- to t t-bar H is governed by nonrelativistic QCD dynamics and one has to employ effective theory methods to make first principles QCD predictions. In this talk we use the effective theory vNRQCD to compute the Higgs energy distribution at next-to-leading logarithmic approximation. It is shown that the corrections are particularly important for smaller c.m. energies. |
0909.3450 | Samuel Wallon | B.Pire, F.Schwennsen, L.Szymanowski, S.Wallon | Pomeron Odderon interference in production of two pi+ pi- pairs at LHC
and ILC | 3 pages, Proceedings of EPS conference Krakow, 16-22 July 2009 | PoS EPS-HEP2009:339,2009 | null | LPT 09-72, CPHT-PC090.0909 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose to look for the Odderon through the production of two pion pairs
in photon collisions at high energies. We calculate the corresponding matrix
elements in kT-factorization and discuss the possibility to reveal the
existence of the perturbative Odderon by charge asymmetries, relying on models
for the generalized distribution amplitudes of pi+ pi-. The application of this
strategy to ultraperipheral collisions at the LHC suffers from the difficulty
to trigger on interesting events and is plagued with severe background problems
in p-p mode. Electron - positron colliders like ILC seem to better suit this
physics.
| [
{
"created": "Fri, 18 Sep 2009 14:32:39 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Pire",
"B.",
""
],
[
"Schwennsen",
"F.",
""
],
[
"Szymanowski",
"L.",
""
],
[
"Wallon",
"S.",
""
]
] | We propose to look for the Odderon through the production of two pion pairs in photon collisions at high energies. We calculate the corresponding matrix elements in kT-factorization and discuss the possibility to reveal the existence of the perturbative Odderon by charge asymmetries, relying on models for the generalized distribution amplitudes of pi+ pi-. The application of this strategy to ultraperipheral collisions at the LHC suffers from the difficulty to trigger on interesting events and is plagued with severe background problems in p-p mode. Electron - positron colliders like ILC seem to better suit this physics. |
hep-ph/0503295 | Piotr Niezurawski | Piotr Niezurawski | Higgs-boson production at the Photon Collider at TESLA | Ph.D. thesis, 105 pages | null | null | null | hep-ph | null | In this thesis feasibility of the precise measurement of the Higgs-boson
production cross section gamma+gamma->higgs->b+bbar at the Photon Collider at
TESLA is studied in detail.
The study is based on the realistic luminosity spectra simulation. The heavy
quark background is estimated using the dedicated code based on NLO QCD
calculations. Other background processes, which were neglected in the earlier
analyses, are also studied. Also the contribution from the overlaying events,
gamma+gamma->hadrons, is taken into account. The non-zero beam crossing angle
and the finite size of colliding bunches are included in the event generation.
The analysis is based on the full detector simulation with realistic b-tagging,
and the criteria of event selection are optimized separately for each
considered Higgs-boson mass.
For the Standard-Model Higgs boson with mass of 120 to 160 GeV the partial
width \Gamma(h->gamma+gamma)BR(h->b+bbar) can be measured with a statistical
accuracy of 2.1-7.7% after one year of the Photon Collider running. The
systematic uncertainties of the measurement are estimated to be of the order of
2%.
For MSSM Higgs bosons A and H, for M_A=200-350 GeV and tan(beta)=7, the
statistical precision of the cross-section measurement is estimated to be
8--34%, for four considered MSSM parameters sets. As heavy neutral Higgs bosons
in this scenario may not be discovered at LHC or at the first stage of the e+e-
collider, an opportunity of being a discovery machine is also studied for the
Photon Collider.
| [
{
"created": "Thu, 31 Mar 2005 11:59:33 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Niezurawski",
"Piotr",
""
]
] | In this thesis feasibility of the precise measurement of the Higgs-boson production cross section gamma+gamma->higgs->b+bbar at the Photon Collider at TESLA is studied in detail. The study is based on the realistic luminosity spectra simulation. The heavy quark background is estimated using the dedicated code based on NLO QCD calculations. Other background processes, which were neglected in the earlier analyses, are also studied. Also the contribution from the overlaying events, gamma+gamma->hadrons, is taken into account. The non-zero beam crossing angle and the finite size of colliding bunches are included in the event generation. The analysis is based on the full detector simulation with realistic b-tagging, and the criteria of event selection are optimized separately for each considered Higgs-boson mass. For the Standard-Model Higgs boson with mass of 120 to 160 GeV the partial width \Gamma(h->gamma+gamma)BR(h->b+bbar) can be measured with a statistical accuracy of 2.1-7.7% after one year of the Photon Collider running. The systematic uncertainties of the measurement are estimated to be of the order of 2%. For MSSM Higgs bosons A and H, for M_A=200-350 GeV and tan(beta)=7, the statistical precision of the cross-section measurement is estimated to be 8--34%, for four considered MSSM parameters sets. As heavy neutral Higgs bosons in this scenario may not be discovered at LHC or at the first stage of the e+e- collider, an opportunity of being a discovery machine is also studied for the Photon Collider. |
1006.2596 | Kenji Fukushima | Kenji Fukushima | Phase diagram of hot and dense QCD constrained by the Statistical Model | 5 pages, 3 figures; all figures updated, results and conclusions not
modified | Phys.Lett.B695:387-391,2011 | 10.1016/j.physletb.2010.11.040 | YITP-10-46 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a prescription to constrain the chiral effective model approach to
the QCD phase diagram using the thermal Statistical Model, which is a
description consistent with the experimental data at the freeze-out. In the
transition region where thermal quantities of hadrons blow up, deconfined
quarks and gluons should smoothly take over the degrees of freedom from hadrons
in the Statistical Model. We use the Polyakov-loop coupled Nambu--Jona-Lasinio
(PNJL) model as an effective description in the quark side. We require that the
validity regions of these descriptions should have an overlap on the phase
diagram, which constrains model uncertainty. Our results favor a phase diagram
with the chiral phase transition located at slightly higher temperature than
deconfinement.
| [
{
"created": "Mon, 14 Jun 2010 04:27:17 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Jun 2010 10:24:55 GMT",
"version": "v2"
}
] | 2011-06-27 | [
[
"Fukushima",
"Kenji",
""
]
] | We propose a prescription to constrain the chiral effective model approach to the QCD phase diagram using the thermal Statistical Model, which is a description consistent with the experimental data at the freeze-out. In the transition region where thermal quantities of hadrons blow up, deconfined quarks and gluons should smoothly take over the degrees of freedom from hadrons in the Statistical Model. We use the Polyakov-loop coupled Nambu--Jona-Lasinio (PNJL) model as an effective description in the quark side. We require that the validity regions of these descriptions should have an overlap on the phase diagram, which constrains model uncertainty. Our results favor a phase diagram with the chiral phase transition located at slightly higher temperature than deconfinement. |
0909.0662 | Felix Br\"ummer | Felix Br\"ummer | Minicharges, Monopoles, and Magnetic Mixing | 4 pages; contribution to 5th Patras workshop on Axions, WIMPs and
WISPs, IPPP Durham, 13-17 July 2009 | null | null | IPPP/09/66; DCPT/09/132 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Minicharged particles (MCPs) arise naturally in extensions of the Standard
Model with hidden sector gauge groups. Many such extensions also contain
magnetic monopoles. For models containing both monopoles and MCPs, we clarify
the role of the Dirac charge quantization condition in restricting the possible
charges. We also show that monopoles of the hidden sector may manifest
themselves as MCPs, by a generalization of the Witten effect, which we call
"magnetic mixing".
| [
{
"created": "Thu, 3 Sep 2009 14:24:52 GMT",
"version": "v1"
}
] | 2009-09-04 | [
[
"Brümmer",
"Felix",
""
]
] | Minicharged particles (MCPs) arise naturally in extensions of the Standard Model with hidden sector gauge groups. Many such extensions also contain magnetic monopoles. For models containing both monopoles and MCPs, we clarify the role of the Dirac charge quantization condition in restricting the possible charges. We also show that monopoles of the hidden sector may manifest themselves as MCPs, by a generalization of the Witten effect, which we call "magnetic mixing". |
1211.0644 | Ahmed Elsayed Dr. | A. Elsayed, S. Khalil, S. Moretti, and A. Moursy | Right-handed sneutrino-antisneutrino oscillations in a TeV scale
Supersymmetric B-L model | 12 pages, 5 figures | Phys. Rev. D 87, 053010 (2013) | 10.1103/PhysRevD.87.053010 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore right-handed sneutrino-antisneutrino mixing in a TeV scale B-L
extension of the Minimal Supersymmetric Standard Model (MSSM), (B-L)SSM, where
a type I seesaw mechanism of light neutrino mass generation is naturally
implemented. The constraints imposed on the mass splitting between heavy
right-handed sneutrino and the corresponding antisneutrino by the experimental
limits set on the light neutrino masses are investigated. We also study direct
pair production of such right-handed sneutrinos at the Large Hadron Collider
(LHC) and its decay modes, emphasising that their decay into same-sign
di-lepton pairs are salient features for probing these particles at the CERN
machine. Finally, the charge asymmetry present in such same-sign di-lepton
signals is also analysed and confirms itself as a further useful handle to
extract information about the oscillation dynamics.
| [
{
"created": "Sat, 3 Nov 2012 22:31:49 GMT",
"version": "v1"
},
{
"created": "Tue, 28 May 2013 20:26:56 GMT",
"version": "v2"
}
] | 2013-05-31 | [
[
"Elsayed",
"A.",
""
],
[
"Khalil",
"S.",
""
],
[
"Moretti",
"S.",
""
],
[
"Moursy",
"A.",
""
]
] | We explore right-handed sneutrino-antisneutrino mixing in a TeV scale B-L extension of the Minimal Supersymmetric Standard Model (MSSM), (B-L)SSM, where a type I seesaw mechanism of light neutrino mass generation is naturally implemented. The constraints imposed on the mass splitting between heavy right-handed sneutrino and the corresponding antisneutrino by the experimental limits set on the light neutrino masses are investigated. We also study direct pair production of such right-handed sneutrinos at the Large Hadron Collider (LHC) and its decay modes, emphasising that their decay into same-sign di-lepton pairs are salient features for probing these particles at the CERN machine. Finally, the charge asymmetry present in such same-sign di-lepton signals is also analysed and confirms itself as a further useful handle to extract information about the oscillation dynamics. |
2001.06383 | Roman Pasechnik | Ant\'onio P. Morais, Roman Pasechnik, Werner Porod | Prospects for New Physics from gauge Left-Right-Colour-Family Grand
Unification hypothesis | 50 pages, 10 figures, 17 tables; discussion somewhat extended;
published version | Eur.Phys.J.C 80 (2020) 12, 1162 | 10.1140/epjc/s10052-020-08710-4 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Given the tremendous phenomenological success of the Standard Model (SM)
framework, it becomes increasingly important to understand to what extent its
specific structure dynamically emerges from unification principles. In this
study, we present a novel anomaly-free supersymmetric (SUSY) Grand Unification
model based upon gauge trinification $[\mathrm{SU}(3)]^3$ symmetry and a local
$\mathrm{SU}(2)_{\mathrm{F}} \times \mathrm{U}(1)_{\mathrm{F}}$ family
symmetry, with particle spectra and gauge symmetries inspired by a possible
reduction pattern $\mathrm{E}_8 \to \mathrm{E}_6\times
\mathrm{SU}(2)_{\mathrm{F}} \times \mathrm{U}(1)_{\mathrm{F}}$, with subsequent
$\mathrm{E}_6\to [\mathrm{SU}(3)]^3$ symmetry breaking step. In this framework,
higher-dimensional operators of $\mathrm{E}_6$ induce the threshold corrections
in the gauge and Yukawa interactions leading, in particular, to only two
distinct Yukawa couplings in the fundamental sector of the resulting
$[\mathrm{SU}(3)]^3\times \mathrm{SU}(2)_{\mathrm{F}} \times
\mathrm{U}(1)_{\mathrm{F}}$ Lagrangian. Among the appealing features emergent
in this framework are the Higgs-matter unification and a unique minimal three
Higgs doublet scalar sector at the electroweak scale as well as tree-level
hierarchies in the light fermion spectra consistent with those observed in
nature. In addition, our framework reveals a variety of prospects for New
Physics searches at the LHC and future colliders such as vector-like fermions,
as well as rich scalar, gauge and neutrino sectors.
| [
{
"created": "Fri, 17 Jan 2020 15:43:34 GMT",
"version": "v1"
},
{
"created": "Sat, 25 Apr 2020 13:56:27 GMT",
"version": "v2"
},
{
"created": "Wed, 12 Jan 2022 16:06:52 GMT",
"version": "v3"
}
] | 2022-01-13 | [
[
"Morais",
"António P.",
""
],
[
"Pasechnik",
"Roman",
""
],
[
"Porod",
"Werner",
""
]
] | Given the tremendous phenomenological success of the Standard Model (SM) framework, it becomes increasingly important to understand to what extent its specific structure dynamically emerges from unification principles. In this study, we present a novel anomaly-free supersymmetric (SUSY) Grand Unification model based upon gauge trinification $[\mathrm{SU}(3)]^3$ symmetry and a local $\mathrm{SU}(2)_{\mathrm{F}} \times \mathrm{U}(1)_{\mathrm{F}}$ family symmetry, with particle spectra and gauge symmetries inspired by a possible reduction pattern $\mathrm{E}_8 \to \mathrm{E}_6\times \mathrm{SU}(2)_{\mathrm{F}} \times \mathrm{U}(1)_{\mathrm{F}}$, with subsequent $\mathrm{E}_6\to [\mathrm{SU}(3)]^3$ symmetry breaking step. In this framework, higher-dimensional operators of $\mathrm{E}_6$ induce the threshold corrections in the gauge and Yukawa interactions leading, in particular, to only two distinct Yukawa couplings in the fundamental sector of the resulting $[\mathrm{SU}(3)]^3\times \mathrm{SU}(2)_{\mathrm{F}} \times \mathrm{U}(1)_{\mathrm{F}}$ Lagrangian. Among the appealing features emergent in this framework are the Higgs-matter unification and a unique minimal three Higgs doublet scalar sector at the electroweak scale as well as tree-level hierarchies in the light fermion spectra consistent with those observed in nature. In addition, our framework reveals a variety of prospects for New Physics searches at the LHC and future colliders such as vector-like fermions, as well as rich scalar, gauge and neutrino sectors. |
0812.1471 | Jean Cleymans | J. Cleymans, G. Hamar, P. Levai, S. Wheaton | Near-thermal equilibrium with Tsallis distributions in heavy ion
collisions | 8 pages, 6 figures | J.Phys.G36:064018,2009 | 10.1088/0954-3899/36/6/064018 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Hadron yields in high energy heavy ion collisions have been fitted and
reproduced by thermal models using standard statistical distributions. These
models give insight into the freeze-out conditions at varying beam energies. In
this paper we investigate changes to this analysis when the statistical
distributions are replaced by Tsallis distributions for hadrons. We investigate
the appearance of near-thermal equilibrium state at SPS and RHIC energies. We
obtain better fits with smaller chi^2 for the same hadron data, as applied
earlier in the thermal fits for SPS energies but not for RHIC energies. This
result indicates that at RHIC energies the final state is very well described
by a single freeze-out temperature with very little room for fluctuations.
| [
{
"created": "Mon, 8 Dec 2008 11:50:18 GMT",
"version": "v1"
},
{
"created": "Tue, 27 Jan 2009 11:44:27 GMT",
"version": "v2"
}
] | 2010-01-15 | [
[
"Cleymans",
"J.",
""
],
[
"Hamar",
"G.",
""
],
[
"Levai",
"P.",
""
],
[
"Wheaton",
"S.",
""
]
] | Hadron yields in high energy heavy ion collisions have been fitted and reproduced by thermal models using standard statistical distributions. These models give insight into the freeze-out conditions at varying beam energies. In this paper we investigate changes to this analysis when the statistical distributions are replaced by Tsallis distributions for hadrons. We investigate the appearance of near-thermal equilibrium state at SPS and RHIC energies. We obtain better fits with smaller chi^2 for the same hadron data, as applied earlier in the thermal fits for SPS energies but not for RHIC energies. This result indicates that at RHIC energies the final state is very well described by a single freeze-out temperature with very little room for fluctuations. |
0807.2133 | Rahul Basu | P. Aurenche (LAPTH), Rahul Basu (IMSc) and M. Fontannaz (LPTHE, Orsay) | Jet-jet and hadron-jet correlations in hadro- and electro-production | LaTeX, 19 pages, 7 figures (9 figure files) | Eur.Phys.J.C57:681-688,2008 | 10.1140/epjc/s10052-008-0731-2 | LAPTH-1259/08, IMSc-2008/06/11, LPT-Orsay-08-59 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss, in the framework of perturbative QCD at next to leading order,
two related observables which are usually considered to provide tests of the
BFKL dynamics : jet-jet correlations at Tevatron energies and forward
particle-jet correlations at HERA. In the first case we study the rapidity gap
dependence of the azimuthal correlations and find slightly too strong
correlations at large gap. In the second case we discuss the cross section as
well as the azimuthal correlations over a rapidity gap range of 5 units. We
find that the requirement of a forward particle imposes strong kinematical
constraints which distort the distributions, notably at small rapidity gaps. We
also show that the decorrelation is stronger in electroproduction than in
hadron-hadron collisions. Unfortunately no data are yet available for
comparison.
| [
{
"created": "Mon, 14 Jul 2008 11:26:07 GMT",
"version": "v1"
}
] | 2008-12-18 | [
[
"Aurenche",
"P.",
"",
"LAPTH"
],
[
"Basu",
"Rahul",
"",
"IMSc"
],
[
"Fontannaz",
"M.",
"",
"LPTHE, Orsay"
]
] | We discuss, in the framework of perturbative QCD at next to leading order, two related observables which are usually considered to provide tests of the BFKL dynamics : jet-jet correlations at Tevatron energies and forward particle-jet correlations at HERA. In the first case we study the rapidity gap dependence of the azimuthal correlations and find slightly too strong correlations at large gap. In the second case we discuss the cross section as well as the azimuthal correlations over a rapidity gap range of 5 units. We find that the requirement of a forward particle imposes strong kinematical constraints which distort the distributions, notably at small rapidity gaps. We also show that the decorrelation is stronger in electroproduction than in hadron-hadron collisions. Unfortunately no data are yet available for comparison. |
2007.11185 | Sarita Sahoo | Sarita Sahoo (1 and 2), Rama Chandra Baral, Pradip Kumar Sahu (1 and
2), and Mina Ketan Parida (2) ((1) Institute of Physics, HBNI, Bhubaneswar,
India, (2) CETMS, Siksha 'O' Anusandhan Deemed to be University, Bhubaneswar,
India) | Study of strange non-strange hadron ratios in pp and p-Pb collisions at
LHC energies | 5 pages, 3 figures | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has been observed that the yields of strange and multi-strange hadrons
relative to pion increase significantly with the event charged-particle
multiplicity. We notice from experimental data that yield ratios between
non-strange hadrons, like p/$\pi$ or hadrons of same strange content, like
$\Lambda$/K$_s^0$, show similar enhancement. We have studied this behavior
within the ambit of a parton model (EPOS3) and A Multi-Phase Transport (AMPT)
model in pp and p-Pb collisions at LHC energies. We investigate model
predictions of yields and yield ratios of different identified hadron
productions as a function of charged-particle multiplicity and compare them
with published ALICE results. The string melting versions of AMPT and EPOS are
found to establish enhancements in the particle yield ratios.
| [
{
"created": "Wed, 22 Jul 2020 03:34:18 GMT",
"version": "v1"
}
] | 2020-07-23 | [
[
"Sahoo",
"Sarita",
"",
"1 and 2"
],
[
"Baral",
"Rama Chandra",
"",
"1 and\n 2"
],
[
"Sahu",
"Pradip Kumar",
"",
"1 and\n 2"
],
[
"Parida",
"Mina Ketan",
""
]
] | It has been observed that the yields of strange and multi-strange hadrons relative to pion increase significantly with the event charged-particle multiplicity. We notice from experimental data that yield ratios between non-strange hadrons, like p/$\pi$ or hadrons of same strange content, like $\Lambda$/K$_s^0$, show similar enhancement. We have studied this behavior within the ambit of a parton model (EPOS3) and A Multi-Phase Transport (AMPT) model in pp and p-Pb collisions at LHC energies. We investigate model predictions of yields and yield ratios of different identified hadron productions as a function of charged-particle multiplicity and compare them with published ALICE results. The string melting versions of AMPT and EPOS are found to establish enhancements in the particle yield ratios. |
hep-ph/0003262 | Gert Aarts | Gert Aarts, Gian Franco Bonini and Christof Wetterich (Heidelberg) | On Thermalization in Classical Scalar Field Theory | 17 pages with 6 eps figures | Nucl.Phys. B587 (2000) 403-418 | 10.1016/S0550-3213(00)00447-8 | HD-THEP-00-20 | hep-ph hep-lat | null | Thermalization of classical fields is investigated in a \phi^4 scalar field
theory in 1+1 dimensions, discretized on a lattice. We numerically integrate
the classical equations of motion using initial conditions sampled from various
nonequilibrium probability distributions. Time-dependent expectation values of
observables constructed from the canonical momentum are compared with thermal
ones. It is found that a closed system, evolving from one initial condition,
thermalizes to high precision in the thermodynamic limit, in a time-averaged
sense. For ensembles consisting of many members with the same energy, we find
that expectation values become stationary - and equal to the thermal values -
in the limit of infinitely many members. Initial ensembles with a nonzero
(noncanonical) spread in the energy density or other conserved quantities
evolve to noncanonical stationary ensembles. In the case of a narrow spread,
asymptotic values of primary observables are only mildly affected. In contrast,
fluctuations and connected correlation functions will differ substantially from
the canonical values. This raises doubts on the use of a straightforward
expansion in terms of 1PI-vertex functions to study thermalization.
| [
{
"created": "Mon, 27 Mar 2000 15:42:44 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Aarts",
"Gert",
"",
"Heidelberg"
],
[
"Bonini",
"Gian Franco",
"",
"Heidelberg"
],
[
"Wetterich",
"Christof",
"",
"Heidelberg"
]
] | Thermalization of classical fields is investigated in a \phi^4 scalar field theory in 1+1 dimensions, discretized on a lattice. We numerically integrate the classical equations of motion using initial conditions sampled from various nonequilibrium probability distributions. Time-dependent expectation values of observables constructed from the canonical momentum are compared with thermal ones. It is found that a closed system, evolving from one initial condition, thermalizes to high precision in the thermodynamic limit, in a time-averaged sense. For ensembles consisting of many members with the same energy, we find that expectation values become stationary - and equal to the thermal values - in the limit of infinitely many members. Initial ensembles with a nonzero (noncanonical) spread in the energy density or other conserved quantities evolve to noncanonical stationary ensembles. In the case of a narrow spread, asymptotic values of primary observables are only mildly affected. In contrast, fluctuations and connected correlation functions will differ substantially from the canonical values. This raises doubts on the use of a straightforward expansion in terms of 1PI-vertex functions to study thermalization. |
0810.4078 | Duc Ninh Le | Le Duc Ninh | One-Loop Yukawa Corrections to the Process pp -> b anti-b H in the
Standard Model at the LHC: Landau Singularities | 184 pages, 2 tables, 36 figures, uses jaxodraw; PhD thesis; one
reference added | null | null | LAPTH-1261/08 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the leading electroweak (EW) corrections to the important
process of Higgs production associated with two bottom quarks at the CERN Large
Hadron Collider (LHC). Our study is restricted to the Standard Model (SM).
At tree-level Higgs production in association with a b-quark pair proceeds
through the small Yukawa bottom coupling in the Standard Model. Even in the
limit where this coupling vanishes, EW one-loop effects, through the top-Higgs
Yukawa coupling in particular, can still trigger this reaction. This
contribution is small for Higgs masses around 120GeV but it quickly picks up
for higher Higgs masses especially because the one-loop amplitude develops a
leading Landau singularity and new thresholds open up. These effects can be
viewed as the production of a pair of top quarks which rescatter to give rise
to Higgs production through WW fusion. An important part of the thesis is
devoted to the topic of Landau singularities in one-loop Feynman diagrams and
application to the specific process of bbH production at the LHC.
Since the 4-point leading Landau singularity is not integrable when the
one-loop amplitude is squared, we regulate the cross section by taking into
account the width of the internal top and W particles. This requires that we
extend the usual box one-loop function to the case of complex masses. We show
how this can be implemented analytically in our case.
We study in some detail the cross section at the LHC as a function of the
Higgs mass and show how some distributions can be drastically affected compared
to the tree-level result.
| [
{
"created": "Wed, 22 Oct 2008 14:45:42 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Nov 2008 10:02:12 GMT",
"version": "v2"
}
] | 2008-11-14 | [
[
"Ninh",
"Le Duc",
""
]
] | We calculate the leading electroweak (EW) corrections to the important process of Higgs production associated with two bottom quarks at the CERN Large Hadron Collider (LHC). Our study is restricted to the Standard Model (SM). At tree-level Higgs production in association with a b-quark pair proceeds through the small Yukawa bottom coupling in the Standard Model. Even in the limit where this coupling vanishes, EW one-loop effects, through the top-Higgs Yukawa coupling in particular, can still trigger this reaction. This contribution is small for Higgs masses around 120GeV but it quickly picks up for higher Higgs masses especially because the one-loop amplitude develops a leading Landau singularity and new thresholds open up. These effects can be viewed as the production of a pair of top quarks which rescatter to give rise to Higgs production through WW fusion. An important part of the thesis is devoted to the topic of Landau singularities in one-loop Feynman diagrams and application to the specific process of bbH production at the LHC. Since the 4-point leading Landau singularity is not integrable when the one-loop amplitude is squared, we regulate the cross section by taking into account the width of the internal top and W particles. This requires that we extend the usual box one-loop function to the case of complex masses. We show how this can be implemented analytically in our case. We study in some detail the cross section at the LHC as a function of the Higgs mass and show how some distributions can be drastically affected compared to the tree-level result. |
1512.03179 | Yu Seon Jeong | Yu Seon Jeong, C. S. Kim and Hye-Sung Lee | Constraints on the $U(1)_L$ gauge boson in a wide mass range | 11 pages, 9 figures | Int. J. Mod. Phys. A 31, 1650059 (2016) | 10.1142/S0217751X16500597 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There is a growing interest for the search of new light gauge bosons. The
small mass of a new boson can turn various kinds of low-energy experiments to a
new discovery machine, depending on their couplings to the standard model
particles. It is important to understand the properties of each type of gauge
boson and their current constraints for a given mass. While the dark photon
(which couples to the electric charges) and the $U(1)_{B-L}$ gauge boson have
been well studied in an extensive mass range, the $U(1)_L$ gauge boson has not
been fully investigated yet. We consider the gauge boson of the $U(1)_L$ in a
wide mass range $m_{Z'} \approx 0 - 10^{12} ~\ev$ and investigate the
constraints on its coupling from various experiments, discussing the
similarities and differences from the dark photon and the $U(1)_{B-L}$ gauge
boson.
| [
{
"created": "Thu, 10 Dec 2015 09:06:11 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Apr 2016 00:41:20 GMT",
"version": "v2"
}
] | 2016-04-20 | [
[
"Jeong",
"Yu Seon",
""
],
[
"Kim",
"C. S.",
""
],
[
"Lee",
"Hye-Sung",
""
]
] | There is a growing interest for the search of new light gauge bosons. The small mass of a new boson can turn various kinds of low-energy experiments to a new discovery machine, depending on their couplings to the standard model particles. It is important to understand the properties of each type of gauge boson and their current constraints for a given mass. While the dark photon (which couples to the electric charges) and the $U(1)_{B-L}$ gauge boson have been well studied in an extensive mass range, the $U(1)_L$ gauge boson has not been fully investigated yet. We consider the gauge boson of the $U(1)_L$ in a wide mass range $m_{Z'} \approx 0 - 10^{12} ~\ev$ and investigate the constraints on its coupling from various experiments, discussing the similarities and differences from the dark photon and the $U(1)_{B-L}$ gauge boson. |
hep-ph/9403362 | J. Gunion | J. Dai, J.F. Gunion, and R. Vega | LHC Detection of Neutral MSSM Higgs Bosons via $gg\rta b\anti b \h\rta
b\anti b b\anti b$ | 10 pages; requires phyzzx.tex and tables.tex; revised to use top
quark mass of 175 GeV and to include additional comments on detection of
small signal/background Higgs bumps; full postscript file including embedded
figures available via anonymous ftp at ucdhep.ucdavis.edu as
[anonymous.gunion]bbbb_susy_revised.ps, preprint UCD-94-7 | Phys.Lett. B345 (1995) 29-35 | 10.1016/0370-2693(94)01497-Z | null | hep-ph | null | We demonstrate that simultaneous detection of two of the neutral Higgs bosons
of the Minimal Supersymmetric Model will be possible at the LHC in the $b\anti
b b\anti b$ final state, provided $\tanb$ is large and $b$-tagging can be
performed with good efficiency and purity. This mode enhances the already
established guarantee that there is no region of supersymmetric parameter space
for which {\it none} of the Higgs bosons of the model can be seen at the LHC.
| [
{
"created": "Fri, 25 Mar 1994 03:49:32 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Oct 1994 00:07:41 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Dai",
"J.",
""
],
[
"Gunion",
"J. F.",
""
],
[
"Vega",
"R.",
""
]
] | We demonstrate that simultaneous detection of two of the neutral Higgs bosons of the Minimal Supersymmetric Model will be possible at the LHC in the $b\anti b b\anti b$ final state, provided $\tanb$ is large and $b$-tagging can be performed with good efficiency and purity. This mode enhances the already established guarantee that there is no region of supersymmetric parameter space for which {\it none} of the Higgs bosons of the model can be seen at the LHC. |
1010.5865 | Yuji Sakai | Yuji Sakai, Takahiro Sasaki, Hiroaki Kouno, Masanobu Yahiro | Comparison between LQCD and PNJL model at finite chemical potentials | Presented at 28th International Symposium on Lattice Field Theory
(Lattice 2010), Villasimius, Sardinia, Italy, 14-19 June, 2010 | PoS Lattice2010:213,2010 | null | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Lattice QCD has the sign problem at real quark chemical potential. There are
some regions with no sign problem; one is the imaginary quark chemical
potential region and the others are the real and imaginary isospin chemical
potential regions. We show that the Polyakov-loop extended Nambu-Jona-Lasinio
(PNJL) model can reproduce LQCD data in the regions. We also determine the
model parameters from the data and predict the QCD phase diagram in the real
quark chemical potential region.
| [
{
"created": "Thu, 28 Oct 2010 05:38:36 GMT",
"version": "v1"
}
] | 2011-03-18 | [
[
"Sakai",
"Yuji",
""
],
[
"Sasaki",
"Takahiro",
""
],
[
"Kouno",
"Hiroaki",
""
],
[
"Yahiro",
"Masanobu",
""
]
] | Lattice QCD has the sign problem at real quark chemical potential. There are some regions with no sign problem; one is the imaginary quark chemical potential region and the others are the real and imaginary isospin chemical potential regions. We show that the Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model can reproduce LQCD data in the regions. We also determine the model parameters from the data and predict the QCD phase diagram in the real quark chemical potential region. |
2211.03727 | Maxim Malyshev | A.V. Lipatov, G.I. Lykasov, M.A. Malyshev | Towards the global fit of the TMD gluon density in the proton from the
LHC data | 26 pages, 11 figures | null | 10.1103/PhysRevD.107.014022 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We propose a new analytical expression for the Transverse Momentum Dependent
(TMD, or unintegrated) gluon density in the proton. Essential phenomenological
parameters are extracted from the LHC data on inclusive hadron production in
$pp$ collisions at low transverse momenta, $p_T \sim 1$~GeV. The latter are
described in the framework of modified soft quark-gluon string model, where
gluonic state and non-zero transverse momentum of partons inside the proton are
taken into account. To determine the parameters important at moderate and large
$x$ we used measurements of inclusive $b$-jet and Higgs boson production at the
LHC as well as latest HERA data on proton structure functions $F_2^c(x, Q^2)$
and $F_2^b(x, Q^2)$ and reduced cross sections $\sigma_{\rm red}^{c}(x,Q^2)$
and $\sigma_{\rm red}^{b}(x,Q^2)$. The Catani-Ciafaloni-Fiorani-Marchesini
evolution equation is applied to extend the initial gluon distribution into the
whole kinematical region. We have achieved simultaneous description of all
considered processes with $\chi^2/d.o.f. = 2.2$, thus moving forward to the
global fit of TMD gluon density from collider data. The obtained TMD gluon
distribution in a proton is available for public usage and implemented into the
TMDlib package and Monte-Carlo event generator PEGASUS.
| [
{
"created": "Mon, 7 Nov 2022 17:58:34 GMT",
"version": "v1"
}
] | 2023-02-01 | [
[
"Lipatov",
"A. V.",
""
],
[
"Lykasov",
"G. I.",
""
],
[
"Malyshev",
"M. A.",
""
]
] | We propose a new analytical expression for the Transverse Momentum Dependent (TMD, or unintegrated) gluon density in the proton. Essential phenomenological parameters are extracted from the LHC data on inclusive hadron production in $pp$ collisions at low transverse momenta, $p_T \sim 1$~GeV. The latter are described in the framework of modified soft quark-gluon string model, where gluonic state and non-zero transverse momentum of partons inside the proton are taken into account. To determine the parameters important at moderate and large $x$ we used measurements of inclusive $b$-jet and Higgs boson production at the LHC as well as latest HERA data on proton structure functions $F_2^c(x, Q^2)$ and $F_2^b(x, Q^2)$ and reduced cross sections $\sigma_{\rm red}^{c}(x,Q^2)$ and $\sigma_{\rm red}^{b}(x,Q^2)$. The Catani-Ciafaloni-Fiorani-Marchesini evolution equation is applied to extend the initial gluon distribution into the whole kinematical region. We have achieved simultaneous description of all considered processes with $\chi^2/d.o.f. = 2.2$, thus moving forward to the global fit of TMD gluon density from collider data. The obtained TMD gluon distribution in a proton is available for public usage and implemented into the TMDlib package and Monte-Carlo event generator PEGASUS. |
hep-ph/0011059 | Stephan Huber | Stephan J. Huber, Michael G. Schmidt | Baryogenesis at the Electroweak Phase Transition for a SUSY Model with a
Gauge Singlet | 5 pages, 6 figures. To appear in the Proceedings of Strong and
Electroweak Matter 2000 (SEWM2000), Marseilles; a reference added | null | 10.1142/9789812799913_0034 | null | hep-ph | null | SUSY models with a gauge singlet easily allow for a strongly first order
electroweak phase transition (EWPT). We discuss the wall profile, in particular
transitional CP violation during the EWPT. We calculate CP violating source
terms for the charginos in the WKB approximation and solve the relevant
transport equations to obtain the generated baryon asymmetry.
| [
{
"created": "Fri, 3 Nov 2000 20:10:10 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Nov 2000 16:18:30 GMT",
"version": "v2"
}
] | 2017-08-23 | [
[
"Huber",
"Stephan J.",
""
],
[
"Schmidt",
"Michael G.",
""
]
] | SUSY models with a gauge singlet easily allow for a strongly first order electroweak phase transition (EWPT). We discuss the wall profile, in particular transitional CP violation during the EWPT. We calculate CP violating source terms for the charginos in the WKB approximation and solve the relevant transport equations to obtain the generated baryon asymmetry. |
1001.2794 | Jorge Perez-Peraza A. | M. Alvarez Madrigal, J. Perez Peraza, V.M. Velasco | The influence of cosmic rays on the size of the Antarctic Ozone Hole | 14 pages and 4 figures | null | null | null | hep-ph physics.ao-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Antarctic region in which severe ozone depletion has taken place is known
as the ozone hole. This region has two basic indicators: the area, where the
ozone abundance is low (size), and the quantity of ozone mass deficit (depth).
The energetic particles that penetrate deeply into the atmosphere and galactic
cosmic rays (GCR) modify the ozone abundance in the stratosphere. With this
research project, we are looking for evidence of a connection between
variations in the cosmic ray flux and variations in the size of the ozone hole.
In addition, we are looking for signs of the kind of processes that physically
connect GCR fluxes with variations in the stratospheric ozone hole size (OHS)
in the Antarctic region. With this goal in mind, we also analyze here the
atmospheric temperature (AT) anomalies, which have often been linked with such
variations. Using Morlet's wavelet spectral analysis to compute the coherence
between two time series, we found that during the analyzed period (1982-2005),
there existed a common signal of around 3 and 5 years between the OHS and GCR
time series, during September and November, respectively. In both cases, the
relationship showed a time-dependent anti-correlation between the two series.
On the other hand, for October the analysis showed a time-dependent correlation
that occurs around 1.7 years. These results seem to indicate that there exist
at least two kinds of modulation processes of GCR fluxes on the OHS that work
simultaneously but that change their relative relevance along the timeline.
| [
{
"created": "Fri, 15 Jan 2010 23:55:32 GMT",
"version": "v1"
}
] | 2010-01-19 | [
[
"Madrigal",
"M. Alvarez",
""
],
[
"Peraza",
"J. Perez",
""
],
[
"Velasco",
"V. M.",
""
]
] | The Antarctic region in which severe ozone depletion has taken place is known as the ozone hole. This region has two basic indicators: the area, where the ozone abundance is low (size), and the quantity of ozone mass deficit (depth). The energetic particles that penetrate deeply into the atmosphere and galactic cosmic rays (GCR) modify the ozone abundance in the stratosphere. With this research project, we are looking for evidence of a connection between variations in the cosmic ray flux and variations in the size of the ozone hole. In addition, we are looking for signs of the kind of processes that physically connect GCR fluxes with variations in the stratospheric ozone hole size (OHS) in the Antarctic region. With this goal in mind, we also analyze here the atmospheric temperature (AT) anomalies, which have often been linked with such variations. Using Morlet's wavelet spectral analysis to compute the coherence between two time series, we found that during the analyzed period (1982-2005), there existed a common signal of around 3 and 5 years between the OHS and GCR time series, during September and November, respectively. In both cases, the relationship showed a time-dependent anti-correlation between the two series. On the other hand, for October the analysis showed a time-dependent correlation that occurs around 1.7 years. These results seem to indicate that there exist at least two kinds of modulation processes of GCR fluxes on the OHS that work simultaneously but that change their relative relevance along the timeline. |
1906.04530 | Koji Ishiwata | Yoshihiro Gunji, Koji Ishiwata | Leptogenesis after superconformal subcritical hybrid inflation | 30 pages, 3 figures, minor corrections, published version | JHEP09(2019)065 | 10.1007/JHEP09(2019)065 | KANAZAWA-19-02 | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider an extended version of superconformal subcritical hybrid
inflation model by introducing three right-handed neutrinos that have the
Majorana mass terms. In the model one of the right-handed sneutrinos plays a
role of the inflaton field, and it decays to reheat the universe after
inflation. The vacuum expectation value for the waterfall field gives an
unconventional pattern of the light neutrino mass matrix, and the neutrino
Yukawa couplings that determine the reheating temperature are not constrained
by the neutrino oscillation data. Consequently thermal leptogenesis or
sneutrino leptogenesis is realized.
| [
{
"created": "Tue, 11 Jun 2019 12:31:19 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Sep 2019 06:48:41 GMT",
"version": "v2"
}
] | 2019-10-02 | [
[
"Gunji",
"Yoshihiro",
""
],
[
"Ishiwata",
"Koji",
""
]
] | We consider an extended version of superconformal subcritical hybrid inflation model by introducing three right-handed neutrinos that have the Majorana mass terms. In the model one of the right-handed sneutrinos plays a role of the inflaton field, and it decays to reheat the universe after inflation. The vacuum expectation value for the waterfall field gives an unconventional pattern of the light neutrino mass matrix, and the neutrino Yukawa couplings that determine the reheating temperature are not constrained by the neutrino oscillation data. Consequently thermal leptogenesis or sneutrino leptogenesis is realized. |
hep-ph/9806240 | Kapogiannis Athanasios | A. S. Kapoyannis, C. N. Ktorides and A. D. Panagiotou (University of
Athens) | An extension of the Statistical Bootstrap Model to include Strangeness.
Implications on Particle Ratios | 29 pages, 38 figures, all the figures are joined in one file.
accepted for publication in Phys. Rev. D | Phys.Rev. D58 (1998) 034009 | 10.1103/PhysRevD.58.034009 | UA/NPPS-1-1998 | hep-ph | null | The Statistical Bootstrap Model (SBM) is extended to describe hadronic
systems which carry the quantum number of strangeness. The study is conducted
in the three-dimensional space of temperature, up-down and strange chemical
potentials, wherein the existence of a ``critical'' surface is established,
which sets the limits of the hadronic phase of matter. A second surface,
defined by the null expectation value of strangeness number is also determined.
The approach of the latter surface to the critical one becomes the focal point
of the present considerations. Two different versions of the extended SBM are
examined, corresponding to the values 2 and 4 for the exponent, which
determines the asymptotic fall-off of the mass spectrum. It is found that the
version with the value 4 has decisive physical advantages. This model is
subsequently adopted to discuss (strange) particle ratios pertaining to
multiparticle production processes, for which a thermal equilibrium mode of
description applies.
| [
{
"created": "Wed, 3 Jun 1998 10:27:57 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Jun 1998 13:33:27 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kapoyannis",
"A. S.",
"",
"University of\n Athens"
],
[
"Ktorides",
"C. N.",
"",
"University of\n Athens"
],
[
"Panagiotou",
"A. D.",
"",
"University of\n Athens"
]
] | The Statistical Bootstrap Model (SBM) is extended to describe hadronic systems which carry the quantum number of strangeness. The study is conducted in the three-dimensional space of temperature, up-down and strange chemical potentials, wherein the existence of a ``critical'' surface is established, which sets the limits of the hadronic phase of matter. A second surface, defined by the null expectation value of strangeness number is also determined. The approach of the latter surface to the critical one becomes the focal point of the present considerations. Two different versions of the extended SBM are examined, corresponding to the values 2 and 4 for the exponent, which determines the asymptotic fall-off of the mass spectrum. It is found that the version with the value 4 has decisive physical advantages. This model is subsequently adopted to discuss (strange) particle ratios pertaining to multiparticle production processes, for which a thermal equilibrium mode of description applies. |
hep-ph/9705409 | Hans-Werner Hammer | M.J. Ramsey-Musolf (1 and 2) and H.-W. Hammer (1 and 3) ((1) INT, U.
of Washington, (2) U. of Connecticut, (3) Inst. f. Kernphysik, U. Mainz) | KN Scattering and the Nucleon Strangeness Radius | 4 pages, RevTex, 1 PS figure, uses epsf.sty, revised to improve
clarity, results unchanged | Phys.Rev.Lett. 80 (1998) 2539-2542 | 10.1103/PhysRevLett.80.2539 | INT DOE/ER/40561-323-INT97-00-170 and MKPH-T-97-14 | hep-ph nucl-th | null | The leading non-zero electric moment of the nucleon strange-quark vector
current is the mean square strangeness radius, $<r_s^2>$. We evaluate the
lightest OZI-allowed contribution to $<r_s^2>$, arising from the kaon cloud,
using dispersion relations. Drawing upon unitarity constraints as well as
$K^{+}N$ scattering and $e^+e^-\to K\bar{K}$ cross section data, we find the
structure of this contribution differs significantly from that suggested by a
variety of QCD-inspired model calculations. In particular, we find evidence for
a strong $\phi$-meson resonance which may enhance the scale of kaon cloud
contribution to an observable level.
| [
{
"created": "Fri, 23 May 1997 18:34:03 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Jan 1998 00:07:16 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Ramsey-Musolf",
"M. J.",
"",
"1 and 2"
],
[
"Hammer",
"H. -W.",
"",
"1 and 3"
]
] | The leading non-zero electric moment of the nucleon strange-quark vector current is the mean square strangeness radius, $<r_s^2>$. We evaluate the lightest OZI-allowed contribution to $<r_s^2>$, arising from the kaon cloud, using dispersion relations. Drawing upon unitarity constraints as well as $K^{+}N$ scattering and $e^+e^-\to K\bar{K}$ cross section data, we find the structure of this contribution differs significantly from that suggested by a variety of QCD-inspired model calculations. In particular, we find evidence for a strong $\phi$-meson resonance which may enhance the scale of kaon cloud contribution to an observable level. |
1702.04759 | Daniel Wegman | C. Simoes and D. Wegman | Radiative Two-Loop Neutrino Masses with Dark Matter | 39 pages, 26 tables, 7 figures | null | 10.1007/JHEP04(2017)148 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the Weinberg operator, we present a full collection of genuine two-loop
models for neutrino mass generation, which contain a dark matter particle as
one of the internal messengers. These models can be constructed simply by
adding new fields that are singlets or doublets of SU(2)L. We ensure the
stability of the dark matter candidate by the addition of a Z2 symmetry that
will also be used to forbid tree level or one-loop diagrams. Thus we only
present models where the main contribution for neutrinos masses is generated
from the corresponding two-loop diagram. We also discuss a short outline
corresponding to some phenomenological characteristics of these models.
| [
{
"created": "Wed, 15 Feb 2017 20:11:00 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Mar 2017 11:20:49 GMT",
"version": "v2"
}
] | 2017-05-24 | [
[
"Simoes",
"C.",
""
],
[
"Wegman",
"D.",
""
]
] | Using the Weinberg operator, we present a full collection of genuine two-loop models for neutrino mass generation, which contain a dark matter particle as one of the internal messengers. These models can be constructed simply by adding new fields that are singlets or doublets of SU(2)L. We ensure the stability of the dark matter candidate by the addition of a Z2 symmetry that will also be used to forbid tree level or one-loop diagrams. Thus we only present models where the main contribution for neutrinos masses is generated from the corresponding two-loop diagram. We also discuss a short outline corresponding to some phenomenological characteristics of these models. |
0908.0314 | Dmitri Kharzeev | Dmitri E. Kharzeev | Chern-Simons current and local parity violation in hot QCD matter | 4 pages, no figures; presented at Quark Matter 2009 Conference,
Knoxville, USA, 29 March - 4 April, 2009; no line numbers | Nucl.Phys.A830:543c-546c,2009 | 10.1016/j.nuclphysa.2009.10.049 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Non-Abelian gauge theories "live" in a space-time with non-trivial topology
that can be characterized by an odd-dimensional Chern-Simons form. In QCD,
Chern-Simons form is induced by the chiral anomaly and the presence of
topological solutions; it opens a possibility for the breaking of P and CP
invariances in strong interactions ("the strong CP problem"). While there is
apparently no global P and CP violation in QCD, here I argue that topological
fluctuations in hot quark-gluon matter can become directly observable in the
presence of a very intense external magnetic field by inducing local P- and CP-
odd effects. These phenomena can be described by using the Maxwell-Chern-Simons
electrodynamics as an effective theory. Local P and CP violation in hot QCD
matter can be observed in experiment through the "chiral magnetic effect" - the
separation of electric charge along the axis of magnetic field that is created
by the colliding relativistic ions. There is a recent evidence for the electric
charge separation relative to the reaction plane of heavy ion collisions from
the STAR Collaboration at RHIC.
| [
{
"created": "Mon, 3 Aug 2009 19:05:34 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Sep 2009 18:48:09 GMT",
"version": "v2"
}
] | 2009-11-18 | [
[
"Kharzeev",
"Dmitri E.",
""
]
] | Non-Abelian gauge theories "live" in a space-time with non-trivial topology that can be characterized by an odd-dimensional Chern-Simons form. In QCD, Chern-Simons form is induced by the chiral anomaly and the presence of topological solutions; it opens a possibility for the breaking of P and CP invariances in strong interactions ("the strong CP problem"). While there is apparently no global P and CP violation in QCD, here I argue that topological fluctuations in hot quark-gluon matter can become directly observable in the presence of a very intense external magnetic field by inducing local P- and CP- odd effects. These phenomena can be described by using the Maxwell-Chern-Simons electrodynamics as an effective theory. Local P and CP violation in hot QCD matter can be observed in experiment through the "chiral magnetic effect" - the separation of electric charge along the axis of magnetic field that is created by the colliding relativistic ions. There is a recent evidence for the electric charge separation relative to the reaction plane of heavy ion collisions from the STAR Collaboration at RHIC. |
2308.00457 | Barbara Linek | Barbara Linek, Agnieszka {\L}uszczak, Marta {\L}uszczak, Roman
Pasechnik, Wolfgang Sch\"afer, Antoni Szczurek | Probing proton structure with $c \bar c$ correlations in ultraperipheral
$pA$ collisions | 22 pages, 14 figures, 1 table | JHEP 10 (2023) 179 | 10.1007/JHEP10(2023)179 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We study the exclusive diffractive $c \bar c$ photoproduction in
ultraperipheral $pA$ collisions. The formalism makes use of off-diagonal
generalizations of the unintegrated gluon distribution, the so-called
generalized transverse momentum dependent distributions (GTMDs). We present two
different formulations. The first one is based directly on gluon GTMD
parametrizations in momentum space. Another option is the calculation of the
GTMD as a Fourier transform of the dipole-nucleon scattering amplitude
$N(Y,\vec{r}_{\perp},\vec{b}_{\perp})$. The latter approach requires some extra
regularization discussed in the paper. Different dipole amplitudes from the
literature are used. Compared to previous calculations in the literature, we
integrate over the full phase space and therefore cross sections for realistic
conditions are obtained. We present distributions in rapidity of $c$ or $\bar
c$, transverse momentum of the $c \bar c$ pair, four-momentum transfer squared
as well as the azimuthal correlation between a sum and a difference of the $c$
and $\bar c$ transverse momenta. The azimuthal correlations are partially due
to the so-called elliptic gluon Wigner distribution. Different models lead to
different modulations in the azimuthal angle. The modulations are generally
smaller than 5%. They depend on the range of transverse momentum selected for
the calculation.
| [
{
"created": "Tue, 1 Aug 2023 11:22:08 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Oct 2023 21:02:04 GMT",
"version": "v2"
}
] | 2024-03-25 | [
[
"Linek",
"Barbara",
""
],
[
"Łuszczak",
"Agnieszka",
""
],
[
"Łuszczak",
"Marta",
""
],
[
"Pasechnik",
"Roman",
""
],
[
"Schäfer",
"Wolfgang",
""
],
[
"Szczurek",
"Antoni",
""
]
] | We study the exclusive diffractive $c \bar c$ photoproduction in ultraperipheral $pA$ collisions. The formalism makes use of off-diagonal generalizations of the unintegrated gluon distribution, the so-called generalized transverse momentum dependent distributions (GTMDs). We present two different formulations. The first one is based directly on gluon GTMD parametrizations in momentum space. Another option is the calculation of the GTMD as a Fourier transform of the dipole-nucleon scattering amplitude $N(Y,\vec{r}_{\perp},\vec{b}_{\perp})$. The latter approach requires some extra regularization discussed in the paper. Different dipole amplitudes from the literature are used. Compared to previous calculations in the literature, we integrate over the full phase space and therefore cross sections for realistic conditions are obtained. We present distributions in rapidity of $c$ or $\bar c$, transverse momentum of the $c \bar c$ pair, four-momentum transfer squared as well as the azimuthal correlation between a sum and a difference of the $c$ and $\bar c$ transverse momenta. The azimuthal correlations are partially due to the so-called elliptic gluon Wigner distribution. Different models lead to different modulations in the azimuthal angle. The modulations are generally smaller than 5%. They depend on the range of transverse momentum selected for the calculation. |
0810.3324 | Alan D. Martin | V.A. Khoze, A.D. Martin and M.G. Ryskin | Soft Diffraction at the LHC | 10 pages, 3 figures; Presented by M.G. Ryskin at the International
Workshop "Hadron Structure and QCD" (HSQCD 2008), June 30 - July 4, 2008,
Gatchina, Russia | null | null | IPPP/08/77, DCPT/08/154 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a triple-Regge analysis of the available pp --> p + X high-energy
data accounting for absorptive corrections. We describe a model for high-energy
soft interactions which includes the whole set of multi-Pomeron (n --> m)
vertices, and give predictions for the LHC.
| [
{
"created": "Mon, 20 Oct 2008 14:35:41 GMT",
"version": "v1"
}
] | 2008-10-21 | [
[
"Khoze",
"V. A.",
""
],
[
"Martin",
"A. D.",
""
],
[
"Ryskin",
"M. G.",
""
]
] | We present a triple-Regge analysis of the available pp --> p + X high-energy data accounting for absorptive corrections. We describe a model for high-energy soft interactions which includes the whole set of multi-Pomeron (n --> m) vertices, and give predictions for the LHC. |
2112.15487 | Aidin Masouminia | Neda Darvishi, M.R. Masouminia | Electroweak Radiative Corrections in Precision LHC Measurements of
$W^\pm/Z^0$+jets | 21 pages, 9 figures and 1 table | Nucl.Phys.B 985 (2022) 116025 | 10.1016/j.nuclphysb.2022.116025 | IPPP/21/59 | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | We calculate the fiducial and differential $W^{\pm}/Z^0+jet(s)$ production
cross-sections in the presence of electroweak (EW) corrections through virtual
loop contributions to the matrix elements (MEs) of the processes and real
partonic cascade emissions. The calculations are carried out for proton-proton
collisions at $\sqrt{s} = 13$ TeV, using Herwig 7 general-purpose Monte-Carlo
event generator with leading-order or next-to-leading-order MEs that are
interfaced with different parton-shower configurations. The results are
compared with precision experimental measurements from ATLAS collaboration and
with similar predictions within the $k_t$-factorisation framework, providing a
test for the validity of the newly-implemented QCD$\oplus$QED$\oplus$EW parton
shower in Herwig 7. It is shown that the inclusion of EW radiations in the
parton shower simulations improves Herwig 7's predictions in describing the
experimental data. Additionally, the inclusion of parton shower-induced real EW
emissions can take precedence over the incorporation of virtual EW corrections
for the simulation of EW-sensitive events.
| [
{
"created": "Fri, 31 Dec 2021 14:40:27 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Jun 2022 13:03:18 GMT",
"version": "v2"
},
{
"created": "Mon, 28 Nov 2022 10:30:51 GMT",
"version": "v3"
}
] | 2022-11-29 | [
[
"Darvishi",
"Neda",
""
],
[
"Masouminia",
"M. R.",
""
]
] | We calculate the fiducial and differential $W^{\pm}/Z^0+jet(s)$ production cross-sections in the presence of electroweak (EW) corrections through virtual loop contributions to the matrix elements (MEs) of the processes and real partonic cascade emissions. The calculations are carried out for proton-proton collisions at $\sqrt{s} = 13$ TeV, using Herwig 7 general-purpose Monte-Carlo event generator with leading-order or next-to-leading-order MEs that are interfaced with different parton-shower configurations. The results are compared with precision experimental measurements from ATLAS collaboration and with similar predictions within the $k_t$-factorisation framework, providing a test for the validity of the newly-implemented QCD$\oplus$QED$\oplus$EW parton shower in Herwig 7. It is shown that the inclusion of EW radiations in the parton shower simulations improves Herwig 7's predictions in describing the experimental data. Additionally, the inclusion of parton shower-induced real EW emissions can take precedence over the incorporation of virtual EW corrections for the simulation of EW-sensitive events. |
hep-ph/9210273 | Kevin Eric Cahill | Kevin Cahill | A More Effective Potential | 5 pages, UNM-92-amep | null | 10.1063/1.43443 | null | hep-ph | null | In theories with spontaneous symmetry breaking, the conventional effective
potential possesses a defective loop expansion. For such theories, the exact
effective potential $V(\phi_c,T)$ is real and convex, but its perturbative
series is complex and concave at small $\phi_c$ and $T$. A more effective
potential is available.
| [
{
"created": "Thu, 29 Oct 1992 05:58:49 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Cahill",
"Kevin",
""
]
] | In theories with spontaneous symmetry breaking, the conventional effective potential possesses a defective loop expansion. For such theories, the exact effective potential $V(\phi_c,T)$ is real and convex, but its perturbative series is complex and concave at small $\phi_c$ and $T$. A more effective potential is available. |
hep-ph/0106221 | Andrei Kataev | A.L.Kataev (Institute for Nuclear Research of the Academy of Sciencies
of Russia, Moscow, Russia), G. Parente (Dep. of Particle Physics, Univ. of
Santiago de Compostela, Santiago de Compostela, Spain), A.V. Sidorov
(Bogoliubov Lab. of Theoreticle Physics, Joint Intsitute for Nuclear
Research, Dubna, Russia) | Fixation of theoretical ambiguities in the improved fits to $xF_3$ CCFR
data at the next-to-next-to-leading order and beyond | The errors in the coefficients $C_{F_3}^{(3)}(n)$ of
($\alpha_s/4\pi)^3 QCD corrections to the Mellin moments of xF_3 structure
function were detected. The application of the corrected results in the fits
resulted in decrease of N$^3$LO values of $\Lambda_{\bar{MS}}^{(4)}$ in
Tables 6,11,12 by 3 MeV only (details are in the enclosed Erratum (in press)) | Phys.Part.Nucl.34:20-46,2003;
Fiz.Elem.Chast.Atom.Yadra34:43-88,2003; Erratum-ibid.38:827-827,2007 | 10.1134/S1063779607060068 | revised CERN-TH/2001-58 | hep-ph | null | Using the results for the NNLO QCD corrections to anomalous dimensions of odd
$xF_3$ Mellin moments and N$^3$LO corrections to their coefficient functions we
improve our previous analysis of the CCFR'97 data for $xF_3$. The possibility
of extracting from the fits of $1/Q^2$-corrections is analysed using three
independent models,including infrared renormalon one. Theoretical quetion of
applicability of the renormalon-type inspired large-$\beta_0$ approximation for
estimating corrections to the coefficient functions of odd $xF_3$ and even
non-singlet $F_2$ moments are considered. The comparison with [1/1] Pad\'e
estimates is given. The obtained NLO and NNLO values of $\alpha_s(M_Z)$ are
supporting the results of our less definite previous analysis and are in
agreement with the world average value $\alpha_s(M_Z)\approx 0.118$. We also
present first N$^3$LO extraction of $\alpha_s(M_Z)$. The interplay between
higher-order perturbative QCD corrections and $1/Q^2$-terms is demonstrated.
The results of our studies are compared with those obtained recently using the
NNLO model of the kernel of DGLAP equation and with the results of the NNLO
fits to CCFR'97 $xF_3$ data, performed by the Bernstein polynomial technique.
| [
{
"created": "Wed, 20 Jun 2001 19:18:08 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Jan 2002 16:35:57 GMT",
"version": "v2"
},
{
"created": "Mon, 4 Jun 2007 12:04:30 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Kataev",
"A. L.",
"",
"Institute for Nuclear Research of the Academy of Sciencies\n of Russia, Moscow, Russia"
],
[
"Parente",
"G.",
"",
"Dep. of Particle Physics, Univ. of\n Santiago de Compostela, Santiago de Compostela, Spain"
],
[
"Sidorov",
"A. V.",
"",
"Bogoliubov Lab. of Theoreticle Physics, Joint Intsitute for Nuclear\n Research, Dubna, Russia"
]
] | Using the results for the NNLO QCD corrections to anomalous dimensions of odd $xF_3$ Mellin moments and N$^3$LO corrections to their coefficient functions we improve our previous analysis of the CCFR'97 data for $xF_3$. The possibility of extracting from the fits of $1/Q^2$-corrections is analysed using three independent models,including infrared renormalon one. Theoretical quetion of applicability of the renormalon-type inspired large-$\beta_0$ approximation for estimating corrections to the coefficient functions of odd $xF_3$ and even non-singlet $F_2$ moments are considered. The comparison with [1/1] Pad\'e estimates is given. The obtained NLO and NNLO values of $\alpha_s(M_Z)$ are supporting the results of our less definite previous analysis and are in agreement with the world average value $\alpha_s(M_Z)\approx 0.118$. We also present first N$^3$LO extraction of $\alpha_s(M_Z)$. The interplay between higher-order perturbative QCD corrections and $1/Q^2$-terms is demonstrated. The results of our studies are compared with those obtained recently using the NNLO model of the kernel of DGLAP equation and with the results of the NNLO fits to CCFR'97 $xF_3$ data, performed by the Bernstein polynomial technique. |
1110.5413 | Yoshio Koide | Yoshio Koide | SU(5) Compatible Yukawaon Model With Two Family Symmetries
U(3)$\times$O(3) | 16 pages, 4 figures | null | null | OU-HET-730/2011; MISC-2011-16 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A yukawaon model which is compatible with an SU(5) GUT model is investigated.
In a previous SU(5) compatible yukawaon model with a U(3) family gauge
symmetry, we could not build a model with a lower energy scale of the family
gauge symmetry breaking scale $\Lambda_{fam}$ than $10^{13}$ GeV, so the family
gauge boson effects in the previous model were invisible. In the present model,
we consider two family symmetries U(3)$\times$O(3), and we assume that the
conventional quarks and leptons $(\bar{\bf 5}+{\bf 10}+{\bf 1})$ of SU(5) are
described as $(\bar{\bf 5}_i+{\bf 10}_\alpha+{\bf 1}_\alpha)$ ($ i=1,2,3$ and
$\alpha=1,2,3$ are indices of U(3) and O(3), respectively). As a result, we
build a model with $\Lambda_{O3} \sim 10^{16}$ GeV and $\Lambda_{U3} \sim
10^{3}$ GeV. The lightest U(3) family gauge boson $A_1^1$ will be observed with
a mass of the order of 1 TeV.
| [
{
"created": "Tue, 25 Oct 2011 06:00:11 GMT",
"version": "v1"
}
] | 2011-10-26 | [
[
"Koide",
"Yoshio",
""
]
] | A yukawaon model which is compatible with an SU(5) GUT model is investigated. In a previous SU(5) compatible yukawaon model with a U(3) family gauge symmetry, we could not build a model with a lower energy scale of the family gauge symmetry breaking scale $\Lambda_{fam}$ than $10^{13}$ GeV, so the family gauge boson effects in the previous model were invisible. In the present model, we consider two family symmetries U(3)$\times$O(3), and we assume that the conventional quarks and leptons $(\bar{\bf 5}+{\bf 10}+{\bf 1})$ of SU(5) are described as $(\bar{\bf 5}_i+{\bf 10}_\alpha+{\bf 1}_\alpha)$ ($ i=1,2,3$ and $\alpha=1,2,3$ are indices of U(3) and O(3), respectively). As a result, we build a model with $\Lambda_{O3} \sim 10^{16}$ GeV and $\Lambda_{U3} \sim 10^{3}$ GeV. The lightest U(3) family gauge boson $A_1^1$ will be observed with a mass of the order of 1 TeV. |
1603.04723 | Diego Aristizabal | D. Aristizabal Sierra, C. Simoes, D. Wegman | Closing in on minimal dark matter and radiative neutrino masses | 18 pages, 6 figures, 2 tables. Two diagrams updated, few
clarifications and references added. Matches version accepted for publication
in JHEP | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study one-loop radiative neutrino mass models in which one of the
beyond-the-standard model fields is either a hypercharge-zero fermion quintet
(minimal dark matter) or a hypercharge-zero scalar septet. By systematically
classifying all possible one-loop such models we identify various processes
that render the neutral component of these representations (dark matter)
cosmologically unstable. Thus, our findings show that these scenarios are in
general not reconcilable with dark matter stability unless tiny couplings or
additional ad hoc symmetries are assumed, in contrast to minimal dark matter
models where stability is entirely due to the standard model gauge symmetry.
For some variants based on higher-order loops we find that $\alpha_2$ reaches a
Landau pole at rather low scales, a couple orders of magnitude from the
characteristic scale of the model itself. Thus, we argue that some of these
variations although consistent with dark matter stability and phenomenological
constraints are hard to reconcile with perturbativity criteria.
| [
{
"created": "Tue, 15 Mar 2016 15:43:32 GMT",
"version": "v1"
},
{
"created": "Fri, 27 May 2016 17:33:32 GMT",
"version": "v2"
}
] | 2016-05-30 | [
[
"Sierra",
"D. Aristizabal",
""
],
[
"Simoes",
"C.",
""
],
[
"Wegman",
"D.",
""
]
] | We study one-loop radiative neutrino mass models in which one of the beyond-the-standard model fields is either a hypercharge-zero fermion quintet (minimal dark matter) or a hypercharge-zero scalar septet. By systematically classifying all possible one-loop such models we identify various processes that render the neutral component of these representations (dark matter) cosmologically unstable. Thus, our findings show that these scenarios are in general not reconcilable with dark matter stability unless tiny couplings or additional ad hoc symmetries are assumed, in contrast to minimal dark matter models where stability is entirely due to the standard model gauge symmetry. For some variants based on higher-order loops we find that $\alpha_2$ reaches a Landau pole at rather low scales, a couple orders of magnitude from the characteristic scale of the model itself. Thus, we argue that some of these variations although consistent with dark matter stability and phenomenological constraints are hard to reconcile with perturbativity criteria. |
1410.2018 | Yasushi Nara Dr | Wei-Tian Deng, Hirotsugu Fujii, Kazunori Itakura, Yasushi Nara | Forward Hadron Productions in high energy pp collisions from a
Monte-Carlo generator for Color Glass Condensate | 10 pages, 9 figures | null | 10.1103/PhysRevD.91.014006 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We develop a Monte-Carlo event generator based on combination of a parton
production formula including the effects of parton saturation (called the DHJ
formula) and hadronization process due to the Lund string fragmentation model.
This event generator is designed for the description of hadron productions at
forward rapidities and in a wide transverse momentum range in high-energy
proton-proton collisions. We analyze transverse momentum spectra of charged
hadrons as well as identified particles; pion, kaon, (anti-)proton at RHIC
energy, and ultra-forward neutral pion spectra from LHCf experiment. We compare
our results to those obtained in other models based on parton-hadron duality
and fragmentation functions.
| [
{
"created": "Wed, 8 Oct 2014 08:30:16 GMT",
"version": "v1"
}
] | 2015-06-23 | [
[
"Deng",
"Wei-Tian",
""
],
[
"Fujii",
"Hirotsugu",
""
],
[
"Itakura",
"Kazunori",
""
],
[
"Nara",
"Yasushi",
""
]
] | We develop a Monte-Carlo event generator based on combination of a parton production formula including the effects of parton saturation (called the DHJ formula) and hadronization process due to the Lund string fragmentation model. This event generator is designed for the description of hadron productions at forward rapidities and in a wide transverse momentum range in high-energy proton-proton collisions. We analyze transverse momentum spectra of charged hadrons as well as identified particles; pion, kaon, (anti-)proton at RHIC energy, and ultra-forward neutral pion spectra from LHCf experiment. We compare our results to those obtained in other models based on parton-hadron duality and fragmentation functions. |
1710.09062 | G\'abor B\'ir\'o | G\'abor B\'ir\'o, Gergely G\'abor Barnaf\"oldi, Tam\'as S\'andor
Bir\'o, Keming Shen | Mass hierarchy and energy scaling of the Tsallis--Pareto parameters in
hadron productions at RHIC and LHC energies | Talk given by G.B\'ir\'o at SQM 2017, Utrecht, 4 pages | null | 10.1051/epjconf/201817114008 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | The latest, high-accuracy identified hadron spectra measurements in
high-energy nuclear collisions led us to the investigation of the strongly
interacting particles and collective effects in small systems. Since
microscopical processes result in a statistical Tsallis-Pareto distribution,
the fit parameters $q$ and $T$ are well suited for identifying system size
scalings and initial conditions. Moreover, parameter values provide information
on the deviation from the extensive, Boltzmann-Gibbs statistics in
finite-volumes. We apply here the fit procedure developed in our earlier study
for proton-proton collisions. The observed mass and $\sqrt{s}$ energy trends in
the hadron production are compared to RHIC dAu and LHC pPb data in different
centrality/multiplicity classes. Here we present new results on mass hierarchy
in pp and pA from light to heavy hadrons.
| [
{
"created": "Wed, 25 Oct 2017 03:15:56 GMT",
"version": "v1"
}
] | 2018-03-14 | [
[
"Bíró",
"Gábor",
""
],
[
"Barnaföldi",
"Gergely Gábor",
""
],
[
"Biró",
"Tamás Sándor",
""
],
[
"Shen",
"Keming",
""
]
] | The latest, high-accuracy identified hadron spectra measurements in high-energy nuclear collisions led us to the investigation of the strongly interacting particles and collective effects in small systems. Since microscopical processes result in a statistical Tsallis-Pareto distribution, the fit parameters $q$ and $T$ are well suited for identifying system size scalings and initial conditions. Moreover, parameter values provide information on the deviation from the extensive, Boltzmann-Gibbs statistics in finite-volumes. We apply here the fit procedure developed in our earlier study for proton-proton collisions. The observed mass and $\sqrt{s}$ energy trends in the hadron production are compared to RHIC dAu and LHC pPb data in different centrality/multiplicity classes. Here we present new results on mass hierarchy in pp and pA from light to heavy hadrons. |
hep-ph/0002058 | null | A.A. Barrientos Bendezu, K.-P.O. Diener and B.A. Kniehl | Virtual Sfermion Effects on Vector-Boson Pair Production at e^+e^-
Colliders | 11 pages (Latex), 3 figures (Postscript); MSSM parameter space
restricted by imposing experimental search limits, references added; accepted
for publication in Phys. Lett. B | Phys.Lett. B478 (2000) 255-261 | 10.1016/S0370-2693(00)00259-8 | DESY 99-189 and MPI/PhT/99-59 | hep-ph | null | We study the quantum effects on vector-boson pair production in e^+e^-
annihilation induced by the sleptons and squarks of the minimal supersymmetric
extension of the standard model (MSSM) in the one-loop approximation. We list
full analytic results, and quantitatively analyze the resulting deviation from
the standard-model prediction of e^+e^- -> W^+W^- for the supergravity-inspired
MSSM. The latter can be rendered small throughout the whole parameter space by
an appropriate choice of renormalization scheme.
| [
{
"created": "Fri, 4 Feb 2000 21:05:23 GMT",
"version": "v1"
},
{
"created": "Wed, 23 Feb 2000 10:57:11 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Bendezu",
"A. A. Barrientos",
""
],
[
"Diener",
"K. -P. O.",
""
],
[
"Kniehl",
"B. A.",
""
]
] | We study the quantum effects on vector-boson pair production in e^+e^- annihilation induced by the sleptons and squarks of the minimal supersymmetric extension of the standard model (MSSM) in the one-loop approximation. We list full analytic results, and quantitatively analyze the resulting deviation from the standard-model prediction of e^+e^- -> W^+W^- for the supergravity-inspired MSSM. The latter can be rendered small throughout the whole parameter space by an appropriate choice of renormalization scheme. |
1002.1026 | Levon Grigoryan | L. Grigoryan | Average formation length in string model | null | Phys.Rev.C81:045207,2010 | 10.1103/PhysRevC.81.045207 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The space-time scales of the hadronization process in the framework of string
model are investigated. It is shown that the average formation lengths of
pseudoscalar mesons, produced in semi-inclusive deep inelastic scattering (DIS)
of leptons on different targets, depend from their electrical charges. In
particular the average formation lengths of positively charged hadrons are
larger than of negatively charged ones. This statement is fulfiled for all
using scaling functions, for $z$ (the fraction of the virtual photon energy
transferred to the detected hadron) larger than 0.15, for all nuclear targets
and any value of the Bjorken scaling variable $x_{Bj}$. In all cases, the main
mechanism is direct production of pseudoscalar mesons. Including in
consideration additional mechanism of production in result of decay of
resonances, leads to decrease of average formation lengths. It is shown that
the average formation lengths of positively (negatively) charged mesons are
slowly rising (decreasing) functions of $x_{Bj}$. The obtained results can be
important, in particular, for the understanding of the hadronization process in
nuclear environment.
| [
{
"created": "Thu, 4 Feb 2010 15:54:20 GMT",
"version": "v1"
}
] | 2010-04-29 | [
[
"Grigoryan",
"L.",
""
]
] | The space-time scales of the hadronization process in the framework of string model are investigated. It is shown that the average formation lengths of pseudoscalar mesons, produced in semi-inclusive deep inelastic scattering (DIS) of leptons on different targets, depend from their electrical charges. In particular the average formation lengths of positively charged hadrons are larger than of negatively charged ones. This statement is fulfiled for all using scaling functions, for $z$ (the fraction of the virtual photon energy transferred to the detected hadron) larger than 0.15, for all nuclear targets and any value of the Bjorken scaling variable $x_{Bj}$. In all cases, the main mechanism is direct production of pseudoscalar mesons. Including in consideration additional mechanism of production in result of decay of resonances, leads to decrease of average formation lengths. It is shown that the average formation lengths of positively (negatively) charged mesons are slowly rising (decreasing) functions of $x_{Bj}$. The obtained results can be important, in particular, for the understanding of the hadronization process in nuclear environment. |
hep-ph/0312278 | Marcus Bleicher | Marcus Bleicher, Horst St\"ocker | Dynamics and freeze-out of hadron resonances at RHIC | Proceedings of the Strange Quark Matter 2003, eprint version differs
from published version | J.Phys.G30:S111-S118,2004 | 10.1088/0954-3899/30/1/010 | null | hep-ph | null | Yields, rapidity and transverse momentum spectra of $\Delta^{++}(1232)$,
$\Lambda(1520)$, $\Sigma^\pm(1385)$ and the meson resonances $K^0(892)$,
$\Phi$, $\rho^0$ and $f_0(980)$ are predicted. Hadronic rescattering leads to a
suppression of reconstructable resonances, especially at low $p_\perp$. A mass
shift of the $\rho$ of 10 MeV is obtained from the microscopic simulation, due
to late stage $\rho$ formation in the cooling pion gas.
| [
{
"created": "Fri, 19 Dec 2003 12:58:53 GMT",
"version": "v1"
}
] | 2010-11-15 | [
[
"Bleicher",
"Marcus",
""
],
[
"Stöcker",
"Horst",
""
]
] | Yields, rapidity and transverse momentum spectra of $\Delta^{++}(1232)$, $\Lambda(1520)$, $\Sigma^\pm(1385)$ and the meson resonances $K^0(892)$, $\Phi$, $\rho^0$ and $f_0(980)$ are predicted. Hadronic rescattering leads to a suppression of reconstructable resonances, especially at low $p_\perp$. A mass shift of the $\rho$ of 10 MeV is obtained from the microscopic simulation, due to late stage $\rho$ formation in the cooling pion gas. |
hep-ph/9710240 | Amir Fariborz | A.S. Deakin, V. Elias, A.H. Fariborz, Ying Xue, Fang Shi, and T.G.
Steele | Broad Sub-Continuum Resonances and the Case for Finite-Energy Sum-Rules | 67 pages, 6 figures, to appear in Z. Phys. C | Eur.Phys.J.C4:693-704,1998 | 10.1007/s100520050239 | null | hep-ph | null | There is a need to go beyond the narrow resonance approximation for QCD
sum-rule channels which are likely to exhibit sensitivity to broad resonance
structures. We first discuss how the first two Laplace sum rules are altered
when one goes beyond the narrow resonance approximation to include possible
subcontinuum resonances with nonzero widths. We then show that the
corresponding first two finite energy sum rules are insensitive to the widths
of such resonances, provided their peaks are symmetric and entirely below the
continuum threshold. We also discuss the reduced sensitivity of the first two
finite energy sum rules to higher dimensional condensates, and show these sum
rules to be insensitive to dimension > 6 condensates containing at least one
q-bar q pair. We extract the direct single-instanton contribution to the F_1
sum rule for the longitudinal component of the axial-vector correlation
function from the known single-instanton contribution to the lowest Laplace sum
rule for the pseudoscalar channel. Finally, we demonstrate how inclusion of
this instanton contribution to the finite-energy sum rule leads to both a
lighter quark mass and to more phenomenologically reasonable higher-mass
resonance contributions within the pseudoscalar channel.
| [
{
"created": "Sat, 4 Oct 1997 18:41:35 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Deakin",
"A. S.",
""
],
[
"Elias",
"V.",
""
],
[
"Fariborz",
"A. H.",
""
],
[
"Xue",
"Ying",
""
],
[
"Shi",
"Fang",
""
],
[
"Steele",
"T. G.",
""
]
] | There is a need to go beyond the narrow resonance approximation for QCD sum-rule channels which are likely to exhibit sensitivity to broad resonance structures. We first discuss how the first two Laplace sum rules are altered when one goes beyond the narrow resonance approximation to include possible subcontinuum resonances with nonzero widths. We then show that the corresponding first two finite energy sum rules are insensitive to the widths of such resonances, provided their peaks are symmetric and entirely below the continuum threshold. We also discuss the reduced sensitivity of the first two finite energy sum rules to higher dimensional condensates, and show these sum rules to be insensitive to dimension > 6 condensates containing at least one q-bar q pair. We extract the direct single-instanton contribution to the F_1 sum rule for the longitudinal component of the axial-vector correlation function from the known single-instanton contribution to the lowest Laplace sum rule for the pseudoscalar channel. Finally, we demonstrate how inclusion of this instanton contribution to the finite-energy sum rule leads to both a lighter quark mass and to more phenomenologically reasonable higher-mass resonance contributions within the pseudoscalar channel. |
1502.03608 | Igor Altsybeev | Igor Altsybeev | Mean transverse momenta correlations in hadron-hadron collisions in MC
toy model with repulsing strings | 7 pages, 6 figures, proceedings of the XI Quark Confinement and the
Hadron Spectrum Conference (2015) | null | 10.1063/1.4938711 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the present work, Monte-Carlo toy model with repulsing quark-gluon strings
in hadron-hadron collisions is described. String repulsion creates transverse
boosts for the string decay products, giving modifications of observables. As
an example, long-range correlations between mean transverse momenta of
particles in two observation windows are studied in MC toy simulation of the
heavy-ion collisions.
| [
{
"created": "Thu, 12 Feb 2015 11:35:47 GMT",
"version": "v1"
}
] | 2016-02-17 | [
[
"Altsybeev",
"Igor",
""
]
] | In the present work, Monte-Carlo toy model with repulsing quark-gluon strings in hadron-hadron collisions is described. String repulsion creates transverse boosts for the string decay products, giving modifications of observables. As an example, long-range correlations between mean transverse momenta of particles in two observation windows are studied in MC toy simulation of the heavy-ion collisions. |
2311.10078 | Aparajitha Karthikeyan | P. S. Bhupal Dev, Bhaskar Dutta, Tao Han, Aparajitha Karthikeyan,
Doojin Kim, Hyunyong Kim | New Physics at Neutron Beam Dump | 9 pages, 4 figures | null | null | MI-HET-821, PITT-PACC-2320 | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We find a new utility of neutrons, usually treated as an experimental
nuisance causing unwanted background, in probing new physics signals. They can
either be radiated from neutrons (neutron bremsstrahlung) or appear through
secondary particles from neutron-on-target interactions, dubbed "neutron beam
dump". As a concrete example, we take the FASER/FASER2 experiment as a
"factory" of high-energy neutrons that interact with the iron dump. We find
that neutron-initiated bremsstrahlung contributions are comparable to
proton-initiated ones, in terms of the resulting flux and the range of
couplings that can be probed. The neutron bremsstrahlung can be used to probe
dark gauge bosons with non-zero neutron coupling. In particular, we investigate
protophobic gauge bosons and find that FASER/FASER2 can probe new parameter
space. We also illustrate the possibility of neutron-induced secondary
particles by considering axion-like particles with electron couplings. We
conclude that the physics potential of FASER/FASER2 in terms of new physics
searches can be greatly extended and improved with the inclusion of neutron
interactions.
| [
{
"created": "Thu, 16 Nov 2023 18:34:45 GMT",
"version": "v1"
}
] | 2023-11-17 | [
[
"Dev",
"P. S. Bhupal",
""
],
[
"Dutta",
"Bhaskar",
""
],
[
"Han",
"Tao",
""
],
[
"Karthikeyan",
"Aparajitha",
""
],
[
"Kim",
"Doojin",
""
],
[
"Kim",
"Hyunyong",
""
]
] | We find a new utility of neutrons, usually treated as an experimental nuisance causing unwanted background, in probing new physics signals. They can either be radiated from neutrons (neutron bremsstrahlung) or appear through secondary particles from neutron-on-target interactions, dubbed "neutron beam dump". As a concrete example, we take the FASER/FASER2 experiment as a "factory" of high-energy neutrons that interact with the iron dump. We find that neutron-initiated bremsstrahlung contributions are comparable to proton-initiated ones, in terms of the resulting flux and the range of couplings that can be probed. The neutron bremsstrahlung can be used to probe dark gauge bosons with non-zero neutron coupling. In particular, we investigate protophobic gauge bosons and find that FASER/FASER2 can probe new parameter space. We also illustrate the possibility of neutron-induced secondary particles by considering axion-like particles with electron couplings. We conclude that the physics potential of FASER/FASER2 in terms of new physics searches can be greatly extended and improved with the inclusion of neutron interactions. |
1007.0248 | Toru Kojo | Toru Kojo, Robert D. Pisarski, A. M. Tsvelik | Covering the Fermi Surface with Patches of Quarkyonic Chiral Spirals | 18 pages, 3 figures | Phys.Rev.D82:074015,2010 | 10.1103/PhysRevD.82.074015 | null | hep-ph cond-mat.str-el hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We argue that in cold, dense quark matter, in the limit of a large number of
colors the ground state is unstable with respect to creation of a complicated
Quarkyonic Chiral Spiral (QCS) state, in which both chiral and translational
symmetries are spontaneously broken. The entire Fermi surface is covered with
patches of QCSs, whose number increases as the quark density does. The low
energy excitations are gapless, given by Wess-Zumino-Novikov-Witten model plus
transverse kinetic terms localized about different patches.
| [
{
"created": "Thu, 1 Jul 2010 20:05:37 GMT",
"version": "v1"
}
] | 2010-10-27 | [
[
"Kojo",
"Toru",
""
],
[
"Pisarski",
"Robert D.",
""
],
[
"Tsvelik",
"A. M.",
""
]
] | We argue that in cold, dense quark matter, in the limit of a large number of colors the ground state is unstable with respect to creation of a complicated Quarkyonic Chiral Spiral (QCS) state, in which both chiral and translational symmetries are spontaneously broken. The entire Fermi surface is covered with patches of QCSs, whose number increases as the quark density does. The low energy excitations are gapless, given by Wess-Zumino-Novikov-Witten model plus transverse kinetic terms localized about different patches. |
1301.2250 | Sudhir Kumar Gupta Dr | David Atwood (Iowa State U), Sudhir Kumar Gupta (Monash U) and Amarjit
Soni (BNL) | Same-sign Tops: A Powerful Diagnostic Test for Models of New Physics | 19 LaTeX pages, 3 Tables and 4 png Figures, accepted version for
publication in JHEP | JHEP 1304 (2013) 035 | 10.1007/JHEP04(2013)035 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the connection between the same sign top (SST) and the top quark
forward-backward asymmetry $A^t_{FB}$. We find that a large class of new
physics models that have been proposed to account for the $A^t_{FB}$ lead to
SST quark production rate much larger than the observed rate at the LHC and
consequently are severely constrained or ruled out. Our model independent,
general, operator analysis shows that none of the tree-level flavor-changing
operators are able to explain $A^t_{FB}$ and simultaneously remain consistent
with the same-sign top-quark production constraints from the LHC data.
| [
{
"created": "Thu, 10 Jan 2013 20:59:59 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Feb 2013 04:51:44 GMT",
"version": "v2"
},
{
"created": "Mon, 25 Mar 2013 03:41:37 GMT",
"version": "v3"
}
] | 2013-04-11 | [
[
"Atwood",
"David",
"",
"Iowa State U"
],
[
"Gupta",
"Sudhir Kumar",
"",
"Monash U"
],
[
"Soni",
"Amarjit",
"",
"BNL"
]
] | We study the connection between the same sign top (SST) and the top quark forward-backward asymmetry $A^t_{FB}$. We find that a large class of new physics models that have been proposed to account for the $A^t_{FB}$ lead to SST quark production rate much larger than the observed rate at the LHC and consequently are severely constrained or ruled out. Our model independent, general, operator analysis shows that none of the tree-level flavor-changing operators are able to explain $A^t_{FB}$ and simultaneously remain consistent with the same-sign top-quark production constraints from the LHC data. |
2107.01526 | Radha Raman Gautam | Radha Raman Gautam, Sanjeev Kumar | A new texture of neutrino mass matrix with three constraints | 10 pages, 2 figures, 2 tables, matches published version | Phys. Lett. B 820 (2021) 136504 | 10.1016/j.physletb.2021.136504 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We present a new texture of neutrino mass matrix having three complex
relations among its elements and study in detail the phenomenological
implications. A characteristic feature of the resulting neutrino mass matrix is
that the atmospheric neutrino mixing angle is predicted to lie in a very narrow
region near $45^{\circ}$. We illustrate how such a form of the neutrino mass
matrix can be realized using the non-Abelian flavor symmetry $A_4$ in the
framework of type-I+II seesaw mechanism.
| [
{
"created": "Sun, 4 Jul 2021 03:13:18 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Jul 2021 06:00:47 GMT",
"version": "v2"
}
] | 2021-07-19 | [
[
"Gautam",
"Radha Raman",
""
],
[
"Kumar",
"Sanjeev",
""
]
] | We present a new texture of neutrino mass matrix having three complex relations among its elements and study in detail the phenomenological implications. A characteristic feature of the resulting neutrino mass matrix is that the atmospheric neutrino mixing angle is predicted to lie in a very narrow region near $45^{\circ}$. We illustrate how such a form of the neutrino mass matrix can be realized using the non-Abelian flavor symmetry $A_4$ in the framework of type-I+II seesaw mechanism. |
1411.4487 | Eugene Zabrodin | G. Eyyubova, V. L. Korotkikh, I. P. Lokhtin, S. V. Petrushanko, A. M.
Snigirev, L. V. Bravina, E. E. Zabrodin | Angular dihadron correlations as interplay of elliptic and triangular
flows | Minor corrections to conform to the journal style | Phys. Rev. C 91, 064907 (2015) | 10.1103/PhysRevC.91.064907 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The hybrid model HYDJET++, which combines soft and hard components, is
employed for the analysis of dihadron angular correlations measured in PbPb
collisions at center-of-mass energy sqrt(s_NN) = 2.76 TeV. The model allows for
study both individual contributions and mutual influence of lower flow
harmonics, v_2 and v_3, on higher harmonics and dihadron angular correlations.
It is shown that the typical structure called ridge in dihadron angular
correlations in a broad pseudorapidity range could appear just as interplay of
v_2 and v_3. Central, semi-central and semi-peripheral collisions were
investigated. Comparison of model results with the experimental data on
dihadron angular correlations is presented for different centralities and
transverse momenta p_T.
| [
{
"created": "Mon, 17 Nov 2014 14:21:20 GMT",
"version": "v1"
},
{
"created": "Thu, 26 Feb 2015 12:24:55 GMT",
"version": "v2"
},
{
"created": "Thu, 11 Jun 2015 14:48:10 GMT",
"version": "v3"
}
] | 2015-06-12 | [
[
"Eyyubova",
"G.",
""
],
[
"Korotkikh",
"V. L.",
""
],
[
"Lokhtin",
"I. P.",
""
],
[
"Petrushanko",
"S. V.",
""
],
[
"Snigirev",
"A. M.",
""
],
[
"Bravina",
"L. V.",
""
],
[
"Zabrodin",
"E. E.",
""
]
] | The hybrid model HYDJET++, which combines soft and hard components, is employed for the analysis of dihadron angular correlations measured in PbPb collisions at center-of-mass energy sqrt(s_NN) = 2.76 TeV. The model allows for study both individual contributions and mutual influence of lower flow harmonics, v_2 and v_3, on higher harmonics and dihadron angular correlations. It is shown that the typical structure called ridge in dihadron angular correlations in a broad pseudorapidity range could appear just as interplay of v_2 and v_3. Central, semi-central and semi-peripheral collisions were investigated. Comparison of model results with the experimental data on dihadron angular correlations is presented for different centralities and transverse momenta p_T. |
1211.1455 | Yusuke Yamada | Yusuke Yamada | Instant uplifted inflation: A solution for a tension between inflation
and SUSY breaking scale | 20 pages, 7 figures v2: typos corrected and references about
inflection point inflation added v3: a subsection and references added
v4:typos corrected | JHEP 07 (2013) 039 | 10.1007/JHEP07(2013)039 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Hubble parameter during the inflationary era must be smaller than the
gravitino mass if the moduli are stabilized by the Kachru-Kallosh-Linde-Trivedi
mechanism. This condition represents the difficulty to combine the low scale
SUSY breaking and the high scale inflation. We propose a simple mechanism which
can naturally separate the inflation scale from the SUSY breaking scale today.
| [
{
"created": "Wed, 7 Nov 2012 05:26:05 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Nov 2012 08:08:41 GMT",
"version": "v2"
},
{
"created": "Sat, 19 Jan 2013 10:09:58 GMT",
"version": "v3"
},
{
"created": "Tue, 4 Jun 2013 05:26:00 GMT",
"version": "v4"
}
] | 2013-07-17 | [
[
"Yamada",
"Yusuke",
""
]
] | The Hubble parameter during the inflationary era must be smaller than the gravitino mass if the moduli are stabilized by the Kachru-Kallosh-Linde-Trivedi mechanism. This condition represents the difficulty to combine the low scale SUSY breaking and the high scale inflation. We propose a simple mechanism which can naturally separate the inflation scale from the SUSY breaking scale today. |
hep-ph/0504259 | Ferenc Sikler | Ferenc Sikler (for the CMS Collaboration) | Hadronic physics with the CMS experiment | Talk given at RHIC School 04, 4th Budapest Winter School on Heavy Ion
Physics, Budapest, Hungary, December 1-3, 2004. To be published in Acta
Physica Hungarica Heavy Ion Physics | ActaPhys.Hung.A25:57-63,2006 | 10.1556/APH.25.2006.1.5 | CERN-CMS-CR-2005-006 | hep-ph | null | The capabilities of the CMS detector are shown and its Heavy Ion program is
outlined.
| [
{
"created": "Wed, 27 Apr 2005 15:09:07 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Apr 2005 09:49:54 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Sikler",
"Ferenc",
"",
"for the CMS Collaboration"
]
] | The capabilities of the CMS detector are shown and its Heavy Ion program is outlined. |
hep-ph/9803259 | Graham Kribs | Graham D. Kribs | Disrupting the one-loop renormalization group invariant M/alpha in
supersymmetry | 43 pages, LaTeX, uses epsf.sty, axodraw.sty, 12 eps figures. Minor
typos corrected. To appear in Nucl. Phys. B | Nucl.Phys. B535 (1998) 41-82 | 10.1016/S0550-3213(98)00593-8 | null | hep-ph | null | It is well known that in low energy supersymmetry the ratio of the gaugino
mass to the gauge coupling squared, M/alpha, is renormalization group invariant
to one-loop. We present a systematic analysis of the corrections to this ratio,
including standard two-loop corrections from gauge and Yukawa couplings,
corrections due to an additional U(1)' gaugino, threshold corrections,
superoblique corrections, corrections due to extra matter, GUT and Planck scale
corrections, and ``corrections'' from messenger sectors with supersymmetry
breaking communicated via gauge-mediation. We show that many of these effects
induce corrections at the level of a few to tens of percent, but some could
give much larger corrections, drastically disrupting the renormalization group
extrapolation of the ratio to higher scales. Our analysis is essentially
model-independent, and therefore can be used to determine the ambiguities in
extrapolating the ratio in any given model between the weak scale and higher
scales.
| [
{
"created": "Fri, 6 Mar 1998 00:40:41 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Oct 1998 22:24:01 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kribs",
"Graham D.",
""
]
] | It is well known that in low energy supersymmetry the ratio of the gaugino mass to the gauge coupling squared, M/alpha, is renormalization group invariant to one-loop. We present a systematic analysis of the corrections to this ratio, including standard two-loop corrections from gauge and Yukawa couplings, corrections due to an additional U(1)' gaugino, threshold corrections, superoblique corrections, corrections due to extra matter, GUT and Planck scale corrections, and ``corrections'' from messenger sectors with supersymmetry breaking communicated via gauge-mediation. We show that many of these effects induce corrections at the level of a few to tens of percent, but some could give much larger corrections, drastically disrupting the renormalization group extrapolation of the ratio to higher scales. Our analysis is essentially model-independent, and therefore can be used to determine the ambiguities in extrapolating the ratio in any given model between the weak scale and higher scales. |
hep-ph/9710371 | bisWa | B. Brahmachari and R. N. Mohapatra | Unified explanation of the Solar and Atmospheric neutrino Puzzles in a
minimal supersymmetric SO(10) model | 4 pages and 4 figures; Version substantially different from the
original one but same conclusions | Phys.Rev. D58 (1998) 015001 | 10.1103/PhysRevD.58.015001 | UMD-PP-98-49 | hep-ph | null | It was recently suggested that in a class of supersymmetric SO(10) models
with Higgs multiplets in 10, and a single $126+\bar{126}$ representations, if
the $\bar{126}$ contributes both to the right handed neutrino masses as well as
to the charged fermion masses, one can have a complete prediction of the
neutrino masses and mixings. It turns out that if one chooses only one 10,
there are no regions in the parameter space where one can have a large
$\nu_{\mu}-\nu_{\tau}$ mixing angle necessary to solve the atmospheric neutrino
deficit while at the same time solving the solar neutrino puzzle via the $\nu_e
\leftrightarrow \nu_{\mu}$ oscillation. We show that this problem can be solved
in a particular class of SO(10) models with a pair of 10 multiplets if we
include the additional left-handed triplet contribution to the light neutrino
mass matrix. This model cannot reproduce the mass and mixing parameters
required to explain the LSND observations neither does it have have a neutrino
hot dark matter.
| [
{
"created": "Wed, 15 Oct 1997 21:01:31 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Feb 1998 20:04:49 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Brahmachari",
"B.",
""
],
[
"Mohapatra",
"R. N.",
""
]
] | It was recently suggested that in a class of supersymmetric SO(10) models with Higgs multiplets in 10, and a single $126+\bar{126}$ representations, if the $\bar{126}$ contributes both to the right handed neutrino masses as well as to the charged fermion masses, one can have a complete prediction of the neutrino masses and mixings. It turns out that if one chooses only one 10, there are no regions in the parameter space where one can have a large $\nu_{\mu}-\nu_{\tau}$ mixing angle necessary to solve the atmospheric neutrino deficit while at the same time solving the solar neutrino puzzle via the $\nu_e \leftrightarrow \nu_{\mu}$ oscillation. We show that this problem can be solved in a particular class of SO(10) models with a pair of 10 multiplets if we include the additional left-handed triplet contribution to the light neutrino mass matrix. This model cannot reproduce the mass and mixing parameters required to explain the LSND observations neither does it have have a neutrino hot dark matter. |
2012.14267 | Pier Francesco Monni | Javier Mazzitelli, Pier Francesco Monni, Paolo Nason, Emanuele Re,
Marius Wiesemann, Giulia Zanderighi | Next-to-next-to-leading order event generation for top-quark pair
production | Journal version | Phys. Rev. Lett. 127, 062001 (2021) | 10.1103/PhysRevLett.127.062001 | MPP-2020-233, CERN-TH-2020-219, LAPTH-049/20 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The production of top-quark pairs in hadronic collisions is among the most
important reactions in modern particle physics phenomenology and constitutes an
instrumental avenue to study the properties of the heaviest quark observed in
nature. The analysis of this process at the Large Hadron Collider relies
heavily on Monte Carlo simulations of the final state events, whose accuracy is
challenged by the outstanding precision of experimental measurements. In this
letter we present the first matched computation of top-quark pair production at
next-to-next-to-leading order in QCD with all-order radiative corrections as
implemented via parton-shower simulations. Besides its intrinsic relevance for
LHC phenomenology, this work also establishes an important step towards the
simulation of other hadronic processes with colour charges in the final state.
| [
{
"created": "Mon, 28 Dec 2020 15:15:44 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Feb 2022 17:49:32 GMT",
"version": "v2"
}
] | 2022-02-25 | [
[
"Mazzitelli",
"Javier",
""
],
[
"Monni",
"Pier Francesco",
""
],
[
"Nason",
"Paolo",
""
],
[
"Re",
"Emanuele",
""
],
[
"Wiesemann",
"Marius",
""
],
[
"Zanderighi",
"Giulia",
""
]
] | The production of top-quark pairs in hadronic collisions is among the most important reactions in modern particle physics phenomenology and constitutes an instrumental avenue to study the properties of the heaviest quark observed in nature. The analysis of this process at the Large Hadron Collider relies heavily on Monte Carlo simulations of the final state events, whose accuracy is challenged by the outstanding precision of experimental measurements. In this letter we present the first matched computation of top-quark pair production at next-to-next-to-leading order in QCD with all-order radiative corrections as implemented via parton-shower simulations. Besides its intrinsic relevance for LHC phenomenology, this work also establishes an important step towards the simulation of other hadronic processes with colour charges in the final state. |
1704.05038 | Nelson R. F. Braga | Nelson R. F. Braga and Luiz F. Ferreira | Bottomonium dissociation in a finite density plasma | In V3: errors in reference citations corrected. Version published in
Physics Letters B. 15 pages, 3 figures | Phys.Lett. B773 (2017) 313-319 | 10.1016/j.physletb.2017.08.037 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a holographic description of the thermal behavior of $ b \bar b$
heavy vector mesons inside a plasma at finite temperature and density. The
meson dissociation in the medium is represented by the decrease in the height
of the spectral function peaks. In order to find a description for the
evolution of the quasi-states with temperature and chemical potential it is
crucial to use a model that is consistent with the decay constant behavior. The
reason is that the height of a spectral function peak is related to the value
of the zero temperature decay constant of the corresponding particle. AdS/QCD
holographic models are in general not consistent with the observation that
decay constants of heavy vector mesons decrease with radial excitation level.
However, it was recently shown that using a soft wall background and
calculating the correlation functions at a finite position of anti-de Sitter
space, associated with an ultraviolet energy scale, it is possible to describe
the observed behavior. Here we extend this proposal to the case of finite
temperature $T $ and chemical potential $\mu $. A clear picture of the
dissociation of bottomonium states as a function of $ \mu $ and $T$ emerges
from the spectral function. The energy scales where the change in chemical
potential leads to changes in the thermal properties of the mesons is
consistent with QCD expectations.
| [
{
"created": "Mon, 17 Apr 2017 17:12:16 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Aug 2017 19:26:50 GMT",
"version": "v2"
},
{
"created": "Fri, 6 Oct 2017 18:23:54 GMT",
"version": "v3"
}
] | 2017-10-10 | [
[
"Braga",
"Nelson R. F.",
""
],
[
"Ferreira",
"Luiz F.",
""
]
] | We present a holographic description of the thermal behavior of $ b \bar b$ heavy vector mesons inside a plasma at finite temperature and density. The meson dissociation in the medium is represented by the decrease in the height of the spectral function peaks. In order to find a description for the evolution of the quasi-states with temperature and chemical potential it is crucial to use a model that is consistent with the decay constant behavior. The reason is that the height of a spectral function peak is related to the value of the zero temperature decay constant of the corresponding particle. AdS/QCD holographic models are in general not consistent with the observation that decay constants of heavy vector mesons decrease with radial excitation level. However, it was recently shown that using a soft wall background and calculating the correlation functions at a finite position of anti-de Sitter space, associated with an ultraviolet energy scale, it is possible to describe the observed behavior. Here we extend this proposal to the case of finite temperature $T $ and chemical potential $\mu $. A clear picture of the dissociation of bottomonium states as a function of $ \mu $ and $T$ emerges from the spectral function. The energy scales where the change in chemical potential leads to changes in the thermal properties of the mesons is consistent with QCD expectations. |
hep-ph/0007289 | Robert Harlander | Robert V. Harlander | Virtual corrections to gg -> H to two loops in the heavy top limit | LaTeX, 9 pages, 2 figures (8 PostScript files) | Phys.Lett. B492 (2000) 74-80 | 10.1016/S0370-2693(00)01042-X | HET-BNL-00/29 | hep-ph | null | The virtual corrections to the production cross section of a Standard Model
Higgs boson are computed up to order \alpha_s^4. Using an effective Lagrangian
for the limit M_t -> \infty, we evaluate the relevant massless two-loop vertex
diagrams by mapping them onto three-loop two-point functions, following a
method recently introduced by Baikov and Smirnov. As a result, we find a
gauge-invariant contribution to the total Higgs production cross section at
NNLO.
| [
{
"created": "Tue, 25 Jul 2000 22:44:34 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Harlander",
"Robert V.",
""
]
] | The virtual corrections to the production cross section of a Standard Model Higgs boson are computed up to order \alpha_s^4. Using an effective Lagrangian for the limit M_t -> \infty, we evaluate the relevant massless two-loop vertex diagrams by mapping them onto three-loop two-point functions, following a method recently introduced by Baikov and Smirnov. As a result, we find a gauge-invariant contribution to the total Higgs production cross section at NNLO. |
1412.7745 | K. S. Babu | K.S. Babu, Shreyashi Chakdar and Rabindra N. Mohapatra | Warm Dark Matter in Two Higgs Doublet Models | 16 pages, 3 figures | Phys. Rev. D 91, 075020 (2015) | 10.1103/PhysRevD.91.075020 | NSF-KITP-14-175\\ OSU-HEP-14-11 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that a neutral scalar field, \sigma, of two Higgs doublet extensions
of the Standard Model incorporating the seesaw mechanism for neutrino masses
can be identified as a consistent {\it warm} dark matter candidate with a mass
of order keV. The relic density of $\sigma$ is correctly reproduced by virtue
of the late decay of a right-handed neutrino N participating in the seesaw
mechanism. Constraints from cosmology determine the mass and lifetime of N to
be M_N = 25 GeV - 20 TeV and \tau_N = (10^{-4} - 1) sec. These models can also
explain the 3.5 keV X-ray anomaly in the extra-galactic spectrum that has been
recently reported in terms of the decay \sigma \to \gamma \gamma. Future tests
of these models at colliders and in astrophysical settings are outlined.
| [
{
"created": "Wed, 24 Dec 2014 20:19:38 GMT",
"version": "v1"
}
] | 2015-05-06 | [
[
"Babu",
"K. S.",
""
],
[
"Chakdar",
"Shreyashi",
""
],
[
"Mohapatra",
"Rabindra N.",
""
]
] | We show that a neutral scalar field, \sigma, of two Higgs doublet extensions of the Standard Model incorporating the seesaw mechanism for neutrino masses can be identified as a consistent {\it warm} dark matter candidate with a mass of order keV. The relic density of $\sigma$ is correctly reproduced by virtue of the late decay of a right-handed neutrino N participating in the seesaw mechanism. Constraints from cosmology determine the mass and lifetime of N to be M_N = 25 GeV - 20 TeV and \tau_N = (10^{-4} - 1) sec. These models can also explain the 3.5 keV X-ray anomaly in the extra-galactic spectrum that has been recently reported in terms of the decay \sigma \to \gamma \gamma. Future tests of these models at colliders and in astrophysical settings are outlined. |
1010.2647 | Scientific Information Service Cern | D. Semikoz (APC) | High-energy astroparticle physics | 29 pages, Lectures given at the 5th CERN-Latin-American School of
High-Energy Physics, Recinto Quirama, Colombia, 15 - 28 Mar 2009 | CERN Yellow Report CERN-2010-001, pp. 363-393 | null | null | hep-ph astro-ph.HE | http://creativecommons.org/licenses/by/3.0/ | In these three lectures I discuss the present status of high-energy
astroparticle physics including Ultra-High-Energy Cosmic Rays (UHECR),
high-energy gamma rays, and neutrinos. The first lecture is devoted to
ultra-high-energy cosmic rays. After a brief introduction to UHECR I discuss
the acceleration of charged particles to highest energies in the astrophysical
objects, their propagation in the intergalactic space, recent observational
results by the Auger and HiRes experiments, anisotropies of UHECR arrival
directions, and secondary gamma rays produced by UHECR. In the second lecture I
review recent results on TeV gamma rays. After a short introduction to
detection techniques, I discuss recent exciting results of the H.E.S.S., MAGIC,
and Milagro experiments on the point-like and diffuse sources of TeV gamma
rays. A special section is devoted to the detection of extragalactic magnetic
fields with TeV gamma-ray measurements. Finally, in the third lecture I discuss
Ultra-High-Energy (UHE) neutrinos. I review three different UHE neutrino
detection techniques and show the present status of searches for diffuse
neutrino flux and point sources of neutrinos.
| [
{
"created": "Wed, 13 Oct 2010 12:37:01 GMT",
"version": "v1"
}
] | 2010-10-14 | [
[
"Semikoz",
"D.",
"",
"APC"
]
] | In these three lectures I discuss the present status of high-energy astroparticle physics including Ultra-High-Energy Cosmic Rays (UHECR), high-energy gamma rays, and neutrinos. The first lecture is devoted to ultra-high-energy cosmic rays. After a brief introduction to UHECR I discuss the acceleration of charged particles to highest energies in the astrophysical objects, their propagation in the intergalactic space, recent observational results by the Auger and HiRes experiments, anisotropies of UHECR arrival directions, and secondary gamma rays produced by UHECR. In the second lecture I review recent results on TeV gamma rays. After a short introduction to detection techniques, I discuss recent exciting results of the H.E.S.S., MAGIC, and Milagro experiments on the point-like and diffuse sources of TeV gamma rays. A special section is devoted to the detection of extragalactic magnetic fields with TeV gamma-ray measurements. Finally, in the third lecture I discuss Ultra-High-Energy (UHE) neutrinos. I review three different UHE neutrino detection techniques and show the present status of searches for diffuse neutrino flux and point sources of neutrinos. |
2004.02117 | Dorota Strozik-Kotlorz | E. Christova, D. Kotlorz and E. Leader | New study of the Boer-Mulders function: Implications for the quark and
hadron transverse momenta | 15 pages, 9 figures (22 eps plots). This is a more complete study of
the subject than in our previous paper arXiv:1909.08218. In this version,
Sec. II and V are modified, Fig.5 is replaced, with corresponding slight
modifications in the Conclusions; matches published version in Phys.Rev.D | Phys. Rev. D 102, 014035 (2020) | 10.1103/PhysRevD.102.014035 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In series of papers the Boer-Mulders function for a given quark flavour has
been extracted: (i) from data on semi-inclusive deep inelastic scattering,
using the simplifying, but theoretically inconsistent, assumption that it is
proportional to the Sivers function for each quark flavour and (ii) from data
on Drell-Yan reactions. In earlier papers, using the semi-inclusive deep
inelastic COMPASS deuteron data on the $\langle\cos\phi_h\rangle$ and
$\langle\cos 2 \phi_h\rangle$ asymmetries, we extracted the collinear
$x_{_{\!B}}$ dependence of the Boer-Mulders function for the sum of the valence
quarks $Q_V=u_V + d_V$ using a small number of model dependent assumptions and
found a significant disagreement with the analysis in (i). In the present
paper, we provide a more complete analysis of the semi-inclusive deep inelastic
scattering reaction, including a discussion of higher twist and
interaction-dependent terms, and also a comparison with the Boer-Mulders
function extracted from data on the Drell-Yan reaction. We confirm that the
proportionality relation of the BM function to the Sivers function, for each
quark flavour, fails badly, but find that it holds rather well if applied to
the nonsinglet valence-quark combination, $Q_V$. We also find good agreement
with the results of the Drell-Yan analysis. Furthermore, we obtain interesting
information on the quark transverse momentum densities in the nucleon and on
the hadron transverse momentum dependence in quark fragmentation.
| [
{
"created": "Sun, 5 Apr 2020 07:42:35 GMT",
"version": "v1"
},
{
"created": "Sun, 28 Jun 2020 04:57:49 GMT",
"version": "v2"
},
{
"created": "Mon, 20 Jul 2020 10:14:45 GMT",
"version": "v3"
}
] | 2020-08-17 | [
[
"Christova",
"E.",
""
],
[
"Kotlorz",
"D.",
""
],
[
"Leader",
"E.",
""
]
] | In series of papers the Boer-Mulders function for a given quark flavour has been extracted: (i) from data on semi-inclusive deep inelastic scattering, using the simplifying, but theoretically inconsistent, assumption that it is proportional to the Sivers function for each quark flavour and (ii) from data on Drell-Yan reactions. In earlier papers, using the semi-inclusive deep inelastic COMPASS deuteron data on the $\langle\cos\phi_h\rangle$ and $\langle\cos 2 \phi_h\rangle$ asymmetries, we extracted the collinear $x_{_{\!B}}$ dependence of the Boer-Mulders function for the sum of the valence quarks $Q_V=u_V + d_V$ using a small number of model dependent assumptions and found a significant disagreement with the analysis in (i). In the present paper, we provide a more complete analysis of the semi-inclusive deep inelastic scattering reaction, including a discussion of higher twist and interaction-dependent terms, and also a comparison with the Boer-Mulders function extracted from data on the Drell-Yan reaction. We confirm that the proportionality relation of the BM function to the Sivers function, for each quark flavour, fails badly, but find that it holds rather well if applied to the nonsinglet valence-quark combination, $Q_V$. We also find good agreement with the results of the Drell-Yan analysis. Furthermore, we obtain interesting information on the quark transverse momentum densities in the nucleon and on the hadron transverse momentum dependence in quark fragmentation. |
1209.1870 | Kalpana Bora | Kalpana Bora and Debajyoti Dutta | Resolving Octant Degeneracy at LBL experiment by combining Daya Bay
Reactor Setup | 4 pages, 8 figures | J. of Physics, Conf. series (IOP UK), vol 481, p 012019, 2014 | 10.1088/1742-6596/481/1/012019 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Long baseline Experiment (LBL) have promised to be a very powerful
experimental set up to study various issues related to Neutrinos. Some ongoing
and planned LBL and medium baseline experiments are - T2K, MINOS, NOvA, LBNE,
LBNO etc. But the long baseline experiments are crippled due to presence of
some parameter degeneracies, like the Octant degeneracy. In this work, we first
show the presence of Octant degeneracy in LBL experiments, and then combine it
with Daya Bay Reactor experiment, at different values of CP violation phase. We
show that the Octant degeneracy in LBNE can be resolved completely with this
proposal.
| [
{
"created": "Mon, 10 Sep 2012 02:35:40 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Jan 2015 11:10:36 GMT",
"version": "v2"
}
] | 2015-06-11 | [
[
"Bora",
"Kalpana",
""
],
[
"Dutta",
"Debajyoti",
""
]
] | Long baseline Experiment (LBL) have promised to be a very powerful experimental set up to study various issues related to Neutrinos. Some ongoing and planned LBL and medium baseline experiments are - T2K, MINOS, NOvA, LBNE, LBNO etc. But the long baseline experiments are crippled due to presence of some parameter degeneracies, like the Octant degeneracy. In this work, we first show the presence of Octant degeneracy in LBL experiments, and then combine it with Daya Bay Reactor experiment, at different values of CP violation phase. We show that the Octant degeneracy in LBNE can be resolved completely with this proposal. |
hep-ph/0004171 | Ambar Ghosal | Ambar Ghosal | A Two Parameter Texture of Nearly Bi-maximal Neutrino Mixing | 14 pages, Latex, One figure, few references added, misprint in Table
I is corrected, Version to appear in Physical Review D | Phys.Rev.D62:092001,2000 | 10.1103/PhysRevD.62.092001 | US-00-04-02 | hep-ph | null | We propose a texture of three generation Majorana-type neutrino mass matrix
in terms of only two parameters which gives rise to nearly bi-maximal mixing
angles. We also demonstrate an explicit realization of such type of neutrino
mass-matrix in the context of an $SU(2)_L$$\times$$U(1)_Y$ model due to higher
dimensional mass terms through the inclusion of discrete $Z_3$$\times$$Z_4$
symmetry and two extra singlet Higgs fields.
| [
{
"created": "Tue, 18 Apr 2000 08:25:44 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Apr 2000 05:56:34 GMT",
"version": "v2"
},
{
"created": "Wed, 10 May 2000 10:11:30 GMT",
"version": "v3"
},
{
"created": "Wed, 2 Aug 2000 11:17:37 GMT",
"version": "v4"
}
] | 2009-12-30 | [
[
"Ghosal",
"Ambar",
""
]
] | We propose a texture of three generation Majorana-type neutrino mass matrix in terms of only two parameters which gives rise to nearly bi-maximal mixing angles. We also demonstrate an explicit realization of such type of neutrino mass-matrix in the context of an $SU(2)_L$$\times$$U(1)_Y$ model due to higher dimensional mass terms through the inclusion of discrete $Z_3$$\times$$Z_4$ symmetry and two extra singlet Higgs fields. |
2211.11766 | Ben Allanach PhD | Ben Allanach (CERN, University of Cambridge) and Joe Davighi (Zurich
University) | The Rumble in the Meson: a leptoquark versus a $Z^\prime$ to fit $b
\rightarrow s \mu^+ \mu^-$ anomalies including 2022 LHCb $R_{K^{(\ast)}}$
measurements | 31 pages, 6 figures. v3 is updated with a new fit including December
2022 LHCb reanalysis of $R_{K^{(\ast)}}$ measurements. Plots and fits
significantly changed but the main conclusion is left unchanged. v4 has minor
changes. v5 has a typo fixed in the caption of Fig 6, v6 has corrected
vertical lines in Fig 6 | null | 10.1007/JHEP04(2023)033 | CERN-TH-2022-181 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We juxtapose global fits of two bottom-up models (an $S_3$ scalar leptoquark
model and a ${B_3-L_2}$ $Z^\prime$ model) of \bsll\ anomalies to flavour data
in order to quantify statistical preference or lack thereof. The leptoquark
model couples directly to left-handed di-muon pairs, whereas the $Z^\prime$
model couples to di-muon pairs with a vector-like coupling.
$B_s-\overline{B_s}$ mixing is a focus because it is typically expected to
disfavour $Z^\prime$ explanations. In two-parameter fits to 247 flavour
observables, including $B_{s/d} \to \mu^+ \mu^-$ branching ratios for which we
provide an updated combination and LHCb $R_{K^{(\ast)}}$ measurements from
December 2022, we show that each model provides a similar improvement in
quality-of-fit of $\sqrt{\Delta \chi^2}=3.6$ with respect to the Standard
Model. The main effect of the $B_s-\overline{B_s}$ mixing constraint in the
$Z^\prime$ model is to disfavour values of the $s_L-b_L$ mixing angle greater
than about $5|V_{cb}|$. This limit is rather loose, meaning that a good fit to
data does not require `alignment' in either quark Yukawa matrix. No curtailment
of the $s_L-b_L$ mixing angle is evident in the $S_3$ model.
| [
{
"created": "Mon, 21 Nov 2022 19:00:00 GMT",
"version": "v1"
},
{
"created": "Fri, 2 Dec 2022 14:43:33 GMT",
"version": "v2"
},
{
"created": "Thu, 19 Jan 2023 17:25:18 GMT",
"version": "v3"
},
{
"created": "Thu, 16 Mar 2023 10:51:18 GMT",
"version": "v4"
},
{
"created": "Thu, 25 May 2023 17:14:57 GMT",
"version": "v5"
},
{
"created": "Thu, 8 Jun 2023 17:09:23 GMT",
"version": "v6"
}
] | 2023-06-09 | [
[
"Allanach",
"Ben",
"",
"CERN, University of Cambridge"
],
[
"Davighi",
"Joe",
"",
"Zurich\n University"
]
] | We juxtapose global fits of two bottom-up models (an $S_3$ scalar leptoquark model and a ${B_3-L_2}$ $Z^\prime$ model) of \bsll\ anomalies to flavour data in order to quantify statistical preference or lack thereof. The leptoquark model couples directly to left-handed di-muon pairs, whereas the $Z^\prime$ model couples to di-muon pairs with a vector-like coupling. $B_s-\overline{B_s}$ mixing is a focus because it is typically expected to disfavour $Z^\prime$ explanations. In two-parameter fits to 247 flavour observables, including $B_{s/d} \to \mu^+ \mu^-$ branching ratios for which we provide an updated combination and LHCb $R_{K^{(\ast)}}$ measurements from December 2022, we show that each model provides a similar improvement in quality-of-fit of $\sqrt{\Delta \chi^2}=3.6$ with respect to the Standard Model. The main effect of the $B_s-\overline{B_s}$ mixing constraint in the $Z^\prime$ model is to disfavour values of the $s_L-b_L$ mixing angle greater than about $5|V_{cb}|$. This limit is rather loose, meaning that a good fit to data does not require `alignment' in either quark Yukawa matrix. No curtailment of the $s_L-b_L$ mixing angle is evident in the $S_3$ model. |
hep-ph/0307333 | Alexander Ilyichev | I. Akushevich, A. Ilyichev, N. Shumeiko, V. Zykunov | Electroweak radiative effects in the single $W$-production at Tevatron
and LHC | 9 pages, 6 figures, contribution to 21st International Symposium On
Lepton And Photon Interactions At High Energies (LP 03) 11-16 Aug 2003,
Batavia, Illinois | null | null | null | hep-ph | null | An alternative calculation of the lowest order electroweak radiative
corrections to the single W-boson production in hadron-hadron collision in the
framework of the quark parton model without any absorption of the collinear
quark singularity into the parton distributions is carried out. Numerical
analysis under Tevatron and LHC kinematic conditions is performed.
| [
{
"created": "Mon, 28 Jul 2003 08:27:51 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Akushevich",
"I.",
""
],
[
"Ilyichev",
"A.",
""
],
[
"Shumeiko",
"N.",
""
],
[
"Zykunov",
"V.",
""
]
] | An alternative calculation of the lowest order electroweak radiative corrections to the single W-boson production in hadron-hadron collision in the framework of the quark parton model without any absorption of the collinear quark singularity into the parton distributions is carried out. Numerical analysis under Tevatron and LHC kinematic conditions is performed. |
hep-ph/0507302 | Parul Rastogi | Parul Rastogi | Distinguishing Between Hierarchical and Lop-sided SO(10) Models | 34 pages | Phys.Rev. D72 (2005) 075002 | 10.1103/PhysRevD.72.075002 | null | hep-ph | null | A comparative study of two predictive SO(10) models, namely the BPW model
(proposed by Babu, Pati and Wilczek) and the AB model (proposed by Albright and
Barr) is done based on their predictions regarding CP and flavor violations.
The values of \Delta m_K, \epsilon_K, \Delta m_{B_d} and S(B_d\to J/\psi K_S)
are found, in both models, to be close to SM predictions, in good agreement
with data. Both models predict that S(B_d\to \phi K_S) should lie in the range
+0.65-0.74, close to the SM prediction and that the EDM of the neutron \approx
(few\times 10^{-26})e-cm. It is found that $Br(\mu\to e\gamma)$ in the AB model
is generically much larger than that in the BPW model, being consistent with
the experimental limit only with a rather heavy SUSY spectrum. The BPW model,
on the other hand, is consistent with a much lighter SUSY spectrum. In the AB
model d_e lies in the range 10^{-27}-10^{-28}e-cm. The BPW model gives d_e to
be typically 100 times lower than that in the AB case. Thus the two models can
be distinguished based on their predictions regarding CP and flavor violating
processes, and can be tested in future experiments.
| [
{
"created": "Tue, 26 Jul 2005 12:56:45 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Rastogi",
"Parul",
""
]
] | A comparative study of two predictive SO(10) models, namely the BPW model (proposed by Babu, Pati and Wilczek) and the AB model (proposed by Albright and Barr) is done based on their predictions regarding CP and flavor violations. The values of \Delta m_K, \epsilon_K, \Delta m_{B_d} and S(B_d\to J/\psi K_S) are found, in both models, to be close to SM predictions, in good agreement with data. Both models predict that S(B_d\to \phi K_S) should lie in the range +0.65-0.74, close to the SM prediction and that the EDM of the neutron \approx (few\times 10^{-26})e-cm. It is found that $Br(\mu\to e\gamma)$ in the AB model is generically much larger than that in the BPW model, being consistent with the experimental limit only with a rather heavy SUSY spectrum. The BPW model, on the other hand, is consistent with a much lighter SUSY spectrum. In the AB model d_e lies in the range 10^{-27}-10^{-28}e-cm. The BPW model gives d_e to be typically 100 times lower than that in the AB case. Thus the two models can be distinguished based on their predictions regarding CP and flavor violating processes, and can be tested in future experiments. |
2111.12119 | Sergei Chekanov V. | S.V. Chekanov and W. Hopkins | Event-based anomaly detection for new physics searches at the LHC using
machine learning | 13 pages, 6 images, contribution to Snowmass 2022 | Universe 2022, 8(10), 494 | 10.3390/universe8100494 | ANL-HEP-17239 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This paper discusses model-agnostic searches for new physics at the Large
Hadron Collider (LHC) using anomaly-detection techniques for the identification
of event signatures that deviate from the Standard Model (SM). We investigate
anomaly detection in the context of machine-learning approaches using
autoencoders, and illustrate expected shapes of invariant masses in the outlier
region using Monte Carlo simulations. Challenges and conceptual limitations of
this approach are discussed.
| [
{
"created": "Tue, 23 Nov 2021 19:28:05 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Feb 2022 16:01:03 GMT",
"version": "v2"
},
{
"created": "Fri, 16 Sep 2022 13:22:03 GMT",
"version": "v3"
}
] | 2022-09-26 | [
[
"Chekanov",
"S. V.",
""
],
[
"Hopkins",
"W.",
""
]
] | This paper discusses model-agnostic searches for new physics at the Large Hadron Collider (LHC) using anomaly-detection techniques for the identification of event signatures that deviate from the Standard Model (SM). We investigate anomaly detection in the context of machine-learning approaches using autoencoders, and illustrate expected shapes of invariant masses in the outlier region using Monte Carlo simulations. Challenges and conceptual limitations of this approach are discussed. |
2310.10852 | Ya-Juan Zheng | Vernon Barger, Kaoru Hagiwara and Ya-Juan Zheng | CP-violating top-Higgs coupling in SMEFT | 14 pages, 6 figures and 1 table; references added | null | null | KEK-TH-2559 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The total cross section of the process $\mu^- \mu^+ \to \nu_\mu \bar{\nu}_\mu
t \bar{t} H$ has strong dependence on the CP phase $\xi$ of the top Yukawa
coupling, where the ratio of $\xi=\pi$ and $\xi = 0$ (SM) grows to 670 at
$\sqrt{s}$ = 30 TeV, 3400 at 100 TeV. We study the cause of the strong energy
dependence and identify its origin as the $(E/m_W^{})^2$ growth of the weak
boson fusion sub-amplitudes, $W_L^- W_L^+ \to t \bar{t} H$, with the two $W$s
are longitudinally polarized. We repeat the study in the SMEFT framework where
EW gauge invariance is manifest and find that the highest energy cross section
is reduced to a quarter of the complex top Yukawa model result, with the same
energy power. By applying the Goldstone boson (GB) equivalence theorem, we
identify the origin of this strong energy growth of the SMEFT amplitudes as
associated with the dimension-6 $\pi^- \pi^+ ttH$ vertex, where $\pi^\pm$
denotes the GB of $W^\pm$. We obtain the unitarity bound on the coefficient of
the SMEFT operator by studying all $2\to2$ and $2\to3$ cross sections in the
$J=0$ channel.
| [
{
"created": "Mon, 16 Oct 2023 21:56:34 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Nov 2023 07:59:41 GMT",
"version": "v2"
}
] | 2023-11-17 | [
[
"Barger",
"Vernon",
""
],
[
"Hagiwara",
"Kaoru",
""
],
[
"Zheng",
"Ya-Juan",
""
]
] | The total cross section of the process $\mu^- \mu^+ \to \nu_\mu \bar{\nu}_\mu t \bar{t} H$ has strong dependence on the CP phase $\xi$ of the top Yukawa coupling, where the ratio of $\xi=\pi$ and $\xi = 0$ (SM) grows to 670 at $\sqrt{s}$ = 30 TeV, 3400 at 100 TeV. We study the cause of the strong energy dependence and identify its origin as the $(E/m_W^{})^2$ growth of the weak boson fusion sub-amplitudes, $W_L^- W_L^+ \to t \bar{t} H$, with the two $W$s are longitudinally polarized. We repeat the study in the SMEFT framework where EW gauge invariance is manifest and find that the highest energy cross section is reduced to a quarter of the complex top Yukawa model result, with the same energy power. By applying the Goldstone boson (GB) equivalence theorem, we identify the origin of this strong energy growth of the SMEFT amplitudes as associated with the dimension-6 $\pi^- \pi^+ ttH$ vertex, where $\pi^\pm$ denotes the GB of $W^\pm$. We obtain the unitarity bound on the coefficient of the SMEFT operator by studying all $2\to2$ and $2\to3$ cross sections in the $J=0$ channel. |
0810.4861 | Malgorzata Worek | C. Englert, B. Jager, M. Worek, D. Zeppenfeld | Observing Strongly Interacting Vector Boson Systems at the CERN Large
Hadron Collider | 31 pages, 17 figures. References added, minor text revisions, version
published by PRD | Phys.Rev.D80:035027,2009 | 10.1103/PhysRevD.80.035027 | KA-TP-21-2008, SFB/CPP-08-88 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore the potential of the CERN Large Hadron Collider to access a
strongly interacting electroweak symmetry breaking sector via weak boson
scattering with WWjj, ZZjj and WZjj final states. As examples of models with
scalar or vector resonances we concentrate on a scenario with a heavy Higgs
boson and on a Warped Higgsless Kaluza-Klein model of narrow spin-one
resonances. The signal and the most prominent background processes are
evaluated using exact tree-level matrix elements including full off-shell and
finite width effects for final states with two tagging jets and four leptons.
Using double forward jet-tagging techniques, we derive dedicated cuts on the
observable jets and charged leptons to suppress Standard Model backgrounds. We
demonstrate that the LHC has substantial sensitivity to strong interactions in
the electroweak symmetry breaking sector.
| [
{
"created": "Mon, 27 Oct 2008 16:33:15 GMT",
"version": "v1"
},
{
"created": "Thu, 3 Sep 2009 14:27:57 GMT",
"version": "v2"
}
] | 2009-09-03 | [
[
"Englert",
"C.",
""
],
[
"Jager",
"B.",
""
],
[
"Worek",
"M.",
""
],
[
"Zeppenfeld",
"D.",
""
]
] | We explore the potential of the CERN Large Hadron Collider to access a strongly interacting electroweak symmetry breaking sector via weak boson scattering with WWjj, ZZjj and WZjj final states. As examples of models with scalar or vector resonances we concentrate on a scenario with a heavy Higgs boson and on a Warped Higgsless Kaluza-Klein model of narrow spin-one resonances. The signal and the most prominent background processes are evaluated using exact tree-level matrix elements including full off-shell and finite width effects for final states with two tagging jets and four leptons. Using double forward jet-tagging techniques, we derive dedicated cuts on the observable jets and charged leptons to suppress Standard Model backgrounds. We demonstrate that the LHC has substantial sensitivity to strong interactions in the electroweak symmetry breaking sector. |
1610.04911 | Gilberto Tavares-Velasco | M. A. Arroyo-Ure\~na, G. Hern\'andez-Tom\'e, G. Tavares-Velasco | $WWV$ $(V=\gamma,Z)$ vertex in the Georgi-Machacek model | 27 pages, 10 figures | Phys. Rev. D 94, 095006 (2016) | 10.1103/PhysRevD.94.095006 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The CP-even static form factors $\Delta\kappa'_V$ and $\Delta Q_V$
($V=\gamma,\, Z$) associated with the $WWV$ vertex are studied in the context
of the Georgi-Machacek model (GMM), which predicts nine new scalar bosons
accommodated in a singlet, a triplet and a fiveplet. General expressions for
the one-loop contributions to $\Delta\kappa'_V$ and $\Delta Q_V$ arising from
neutral, singly and doubly charged scalar bosons are obtained in terms of both
parametric integrals and Passarino-Veltman scalar functions, which can be
numerically evaluated. It is found that the GMM yields 15 (28) distinct
contributions to $\Delta\kappa'_\gamma$ and $\Delta Q_\gamma$
($\Delta\kappa'_Z$ and $\Delta Q_Z$), though several of them are naturally
suppressed. A numerical analysis is done in the region of parameter space still
consistent with current experimental data and it is found that the largest
contributions to $\Delta\kappa'_V$ arise from Feynman diagrams with two
nondegenerate scalar bosons in the loop, with values of the order of
$a=g^2/(96\pi^2)$ reached when there is a large splitting between the masses of
these scalar bosons. As for $\Delta Q_V$, it reaches values as large as
$10^{-2}a$ for the lightest allowed scalar bosons, but it decreases rapidly as
one of the masses of the scalar bosons becomes large. Among the new
contributions of the GMM to the $\Delta\kappa'_V$ and $\Delta Q_V$ form factors
are those induced by the $H_5^\pm W^\mp Z$ vertex, which arises at the
tree-level and is a unique prediction of this model.
| [
{
"created": "Sun, 16 Oct 2016 20:29:00 GMT",
"version": "v1"
}
] | 2016-11-09 | [
[
"Arroyo-Ureña",
"M. A.",
""
],
[
"Hernández-Tomé",
"G.",
""
],
[
"Tavares-Velasco",
"G.",
""
]
] | The CP-even static form factors $\Delta\kappa'_V$ and $\Delta Q_V$ ($V=\gamma,\, Z$) associated with the $WWV$ vertex are studied in the context of the Georgi-Machacek model (GMM), which predicts nine new scalar bosons accommodated in a singlet, a triplet and a fiveplet. General expressions for the one-loop contributions to $\Delta\kappa'_V$ and $\Delta Q_V$ arising from neutral, singly and doubly charged scalar bosons are obtained in terms of both parametric integrals and Passarino-Veltman scalar functions, which can be numerically evaluated. It is found that the GMM yields 15 (28) distinct contributions to $\Delta\kappa'_\gamma$ and $\Delta Q_\gamma$ ($\Delta\kappa'_Z$ and $\Delta Q_Z$), though several of them are naturally suppressed. A numerical analysis is done in the region of parameter space still consistent with current experimental data and it is found that the largest contributions to $\Delta\kappa'_V$ arise from Feynman diagrams with two nondegenerate scalar bosons in the loop, with values of the order of $a=g^2/(96\pi^2)$ reached when there is a large splitting between the masses of these scalar bosons. As for $\Delta Q_V$, it reaches values as large as $10^{-2}a$ for the lightest allowed scalar bosons, but it decreases rapidly as one of the masses of the scalar bosons becomes large. Among the new contributions of the GMM to the $\Delta\kappa'_V$ and $\Delta Q_V$ form factors are those induced by the $H_5^\pm W^\mp Z$ vertex, which arises at the tree-level and is a unique prediction of this model. |
hep-ph/9905533 | Eugene Levin | Eugene Levin (Tel Aviv U.) | Low x News for Monte Carlo | 38 pages, 27 figures in latex and eps files | null | null | TAUP - 2574 - 99 | hep-ph | null | This talk,given at Monte Carlo Workshop, is a review of news in low $x$
physics which, I think, would be useful for writing of the Monte Carlo codes.
The following topics are discussed here: (i) the next-to-leading order BFKL
Pomeron; (ii) two indications for shadowing corrections (SC) in DIS from HERA
data; (iii) matching of "soft" and "hard" photon - proton interactions; and
(iv) survival probability for large rapidity gap (LRG) processes in
hadron-hadron scattering and DIS. I hope, that our current understanding of
these topics will allow us to narrow the gap between the MC codes and our
microscopic theory - QCD.
| [
{
"created": "Fri, 28 May 1999 09:32:37 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Levin",
"Eugene",
"",
"Tel Aviv U."
]
] | This talk,given at Monte Carlo Workshop, is a review of news in low $x$ physics which, I think, would be useful for writing of the Monte Carlo codes. The following topics are discussed here: (i) the next-to-leading order BFKL Pomeron; (ii) two indications for shadowing corrections (SC) in DIS from HERA data; (iii) matching of "soft" and "hard" photon - proton interactions; and (iv) survival probability for large rapidity gap (LRG) processes in hadron-hadron scattering and DIS. I hope, that our current understanding of these topics will allow us to narrow the gap between the MC codes and our microscopic theory - QCD. |
2105.04585 | Federico Buccioni | Bakul Agarwal, Federico Buccioni, Andreas von Manteuffel, Lorenzo
Tancredi | Two-loop helicity amplitudes for diphoton plus jet production in full
color | 10 pages, 1 table, analytic results at
https://gitlab.msu.edu/vmante/aajamp-symb | null | 10.1103/PhysRevLett.127.262001 | MSUHEP-21-010, OUTP-21-12P | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the complete two-loop corrections in massless QCD for the
production of two photons and a jet, taking into account all color structures.
In particular, we analytically compute all two-loop helicity amplitudes for the
quark-antiquark, quark-gluon, and antiquark-gluon channel, and check them with
an independent calculation of the polarization-summed interference with the
tree amplitude. This is the first time that two-loop QCD corrections to a
five-point scattering process have been computed beyond the leading-color
approximation for all helicity configurations.
| [
{
"created": "Mon, 10 May 2021 18:00:58 GMT",
"version": "v1"
}
] | 2022-01-05 | [
[
"Agarwal",
"Bakul",
""
],
[
"Buccioni",
"Federico",
""
],
[
"von Manteuffel",
"Andreas",
""
],
[
"Tancredi",
"Lorenzo",
""
]
] | We present the complete two-loop corrections in massless QCD for the production of two photons and a jet, taking into account all color structures. In particular, we analytically compute all two-loop helicity amplitudes for the quark-antiquark, quark-gluon, and antiquark-gluon channel, and check them with an independent calculation of the polarization-summed interference with the tree amplitude. This is the first time that two-loop QCD corrections to a five-point scattering process have been computed beyond the leading-color approximation for all helicity configurations. |
2407.14449 | Mahammad Sabir Ali | Mahammad Sabir Ali, Chowdhury Aminul Islam, Rishi Sharma | QCD phase diagram in the $T-eB$ plane for varying pion mass | 19 pages, 12 captioned figures, comments are welcome | null | null | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the effect of a varying pion mass on the quantum chromodynamics
(QCD) phase diagram in the presence of an external magnetic field, aiming to
understand it using Nambu\textendash Jona-Lasinio like effective models. We
compare results from both its local and nonlocal versions. In both cases, we
find that the inverse magnetic catalysis (IMC) near the crossover is eliminated
with increasing pion mass, while the decreasing trend of crossover temperature
with increasing magnetic field persists for pion mass values at least up to
$440$ MeV. Thus, the models are capable of capturing qualitatively the results
found by lattice QCD (LQCD) for heavy (unphysical) pions. The key feature in
the models is the incorporation of the effect of a reduction in the coupling
constant with increasing energy. Along with reproducing the IMC effect, it
enables models to describe the effects of heavier current quark masses without
introducing additional parameters. For the local NJL model, this agreement
depends on how the parameters of the model are fit at the physical point. In
this respect, the nonlocal version, which, due to its formulation,
automatically exhibits the IMC effect around the crossover region, captures the
physics more naturally.
| [
{
"created": "Fri, 19 Jul 2024 16:44:13 GMT",
"version": "v1"
}
] | 2024-07-22 | [
[
"Ali",
"Mahammad Sabir",
""
],
[
"Islam",
"Chowdhury Aminul",
""
],
[
"Sharma",
"Rishi",
""
]
] | We study the effect of a varying pion mass on the quantum chromodynamics (QCD) phase diagram in the presence of an external magnetic field, aiming to understand it using Nambu\textendash Jona-Lasinio like effective models. We compare results from both its local and nonlocal versions. In both cases, we find that the inverse magnetic catalysis (IMC) near the crossover is eliminated with increasing pion mass, while the decreasing trend of crossover temperature with increasing magnetic field persists for pion mass values at least up to $440$ MeV. Thus, the models are capable of capturing qualitatively the results found by lattice QCD (LQCD) for heavy (unphysical) pions. The key feature in the models is the incorporation of the effect of a reduction in the coupling constant with increasing energy. Along with reproducing the IMC effect, it enables models to describe the effects of heavier current quark masses without introducing additional parameters. For the local NJL model, this agreement depends on how the parameters of the model are fit at the physical point. In this respect, the nonlocal version, which, due to its formulation, automatically exhibits the IMC effect around the crossover region, captures the physics more naturally. |
hep-ph/0106179 | Christophe Ringeval | Christophe Ringeval | Fermionic massive modes along cosmic strings | 27 pages, 15 figures, uses ReVTeX. Shortened version, accepted for
publication in Phys. Rev. D | Phys.Rev. D64 (2001) 123505 | 10.1103/PhysRevD.64.123505 | null | hep-ph astro-ph gr-qc | null | The influence on cosmic string dynamics of fermionic massive bound states
propagating in the vortex, and getting their mass only from coupling to the
string forming Higgs field, is studied. Such massive fermionic currents are
numerically found to exist for a wide range of model parameters and seen to
modify drastically the usual string dynamics coming from the zero mode currents
alone. In particular, by means of a quantization procedure, a new equation of
state describing cosmic strings with any kind of fermionic current, massive or
massless, is derived and found to involve, at least, one state parameter per
trapped fermion species. This equation of state exhibits transitions from
subsonic to supersonic regimes while the massive modes are filled.
| [
{
"created": "Fri, 15 Jun 2001 22:40:34 GMT",
"version": "v1"
},
{
"created": "Mon, 5 Nov 2001 16:28:36 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Ringeval",
"Christophe",
""
]
] | The influence on cosmic string dynamics of fermionic massive bound states propagating in the vortex, and getting their mass only from coupling to the string forming Higgs field, is studied. Such massive fermionic currents are numerically found to exist for a wide range of model parameters and seen to modify drastically the usual string dynamics coming from the zero mode currents alone. In particular, by means of a quantization procedure, a new equation of state describing cosmic strings with any kind of fermionic current, massive or massless, is derived and found to involve, at least, one state parameter per trapped fermion species. This equation of state exhibits transitions from subsonic to supersonic regimes while the massive modes are filled. |
hep-ph/9503215 | null | K.S. Babu and S.M. Barr | "An SO(10) Solution to the Puzzle of Quark and Lepton Masses" | 17 pages, in Plain LaTeX (includes 2 LaTeX figures) | Phys.Rev.Lett.75:2088-2091,1995 | 10.1103/PhysRevLett.75.2088 | BA-95-11 | hep-ph | null | It is shown that almost all features of the quark and lepton masses can be
satisfactorily and simply explained without family symmetry, including the
threefold mass hierarchy among the generations, and the relations $m_{\tau}^0 =
m_b^0$, $m_{\mu}^0 = 3 m_s^0$, $m_e^0 = \frac{1}{3} m_d^0$, $m_u^0/m_t^0 <<
m_d^0/m_b^0$, $\tan \theta_c = \sqrt{m_d^0/m_s^0}$, $V_{cb} <<
\sqrt{m_s^0/m_b^0}$, and $V_{ub} \sim V_{cb}V_{us}$. Various aspects of the
group theory of $SO(10)$ play an essential role in explaining these relations.
The form of the mass matrices, rather than being imposed arbitrarily, emerges
naturally from a simple structure at the unification scale. This structure
involves only vector, spinor and adjoint representations. There are distinctive
and testable predictions for $\tan \beta$ and the neutrino mixing angles.
| [
{
"created": "Thu, 2 Mar 1995 19:18:26 GMT",
"version": "v1"
}
] | 2011-05-12 | [
[
"Babu",
"K. S.",
""
],
[
"Barr",
"S. M.",
""
]
] | It is shown that almost all features of the quark and lepton masses can be satisfactorily and simply explained without family symmetry, including the threefold mass hierarchy among the generations, and the relations $m_{\tau}^0 = m_b^0$, $m_{\mu}^0 = 3 m_s^0$, $m_e^0 = \frac{1}{3} m_d^0$, $m_u^0/m_t^0 << m_d^0/m_b^0$, $\tan \theta_c = \sqrt{m_d^0/m_s^0}$, $V_{cb} << \sqrt{m_s^0/m_b^0}$, and $V_{ub} \sim V_{cb}V_{us}$. Various aspects of the group theory of $SO(10)$ play an essential role in explaining these relations. The form of the mass matrices, rather than being imposed arbitrarily, emerges naturally from a simple structure at the unification scale. This structure involves only vector, spinor and adjoint representations. There are distinctive and testable predictions for $\tan \beta$ and the neutrino mixing angles. |
hep-ph/0403283 | Georgios Choudalakis | Georgios Choudalakis | Non-oscillating neutrinos in vacuum | 12 pages, 8 figures | null | null | null | hep-ph | null | Demonstration of how matter effects can result into non-oscillating neutrinos
in vacuum, after they have passed through an appropriate distribution of
matter.
A brief discussion about matter effects in neutrinos oscillation is also
made.
| [
{
"created": "Mon, 29 Mar 2004 18:23:49 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Mar 2004 15:59:12 GMT",
"version": "v2"
},
{
"created": "Wed, 31 Mar 2004 19:40:03 GMT",
"version": "v3"
}
] | 2016-09-06 | [
[
"Choudalakis",
"Georgios",
""
]
] | Demonstration of how matter effects can result into non-oscillating neutrinos in vacuum, after they have passed through an appropriate distribution of matter. A brief discussion about matter effects in neutrinos oscillation is also made. |
hep-ph/0610399 | Gurjav Ganbold | G. Ganbold | Mesons and Glueballs: A Quantum Field Approach | 11 pages, 1 table, 5 fugures, typos corrected, minor modification in
text, content unchanged. A talk given by GG at the 18th Int Baldin Seminar on
High Energy Physics Problems "Relativistic Nuclear Physics & QCD", Sept.
25-30, 2006, Dubna (Russia) | null | null | null | hep-ph | null | The spectrum of two-particle bound states is investigated within a
relativistic quantum-field model of interacting quarks and gluons confined
analytically. The hadronization process of mesons and glueballs is described by
using the Bethe-Salpeter equation. Provided by a minimal set of physical
parameters (the quark masses, the coupling constant and the confinement scale),
the model satisfactorily describes the meson ground-states, orbital and radial
excitations in a wide range from $140 {\rm MeV}$ to $9.5 {\rm GeV}$. The
estimated values for the coupling constant and the lowest-state glueball mass
are in reasonable agreement with experimental data.
| [
{
"created": "Mon, 30 Oct 2006 10:50:58 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Nov 2006 09:31:17 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Ganbold",
"G.",
""
]
] | The spectrum of two-particle bound states is investigated within a relativistic quantum-field model of interacting quarks and gluons confined analytically. The hadronization process of mesons and glueballs is described by using the Bethe-Salpeter equation. Provided by a minimal set of physical parameters (the quark masses, the coupling constant and the confinement scale), the model satisfactorily describes the meson ground-states, orbital and radial excitations in a wide range from $140 {\rm MeV}$ to $9.5 {\rm GeV}$. The estimated values for the coupling constant and the lowest-state glueball mass are in reasonable agreement with experimental data. |
hep-ph/9911482 | Passarino Giampiero | G. Passarino (Turin Univ. and INFN Turin) | Unstable Particles and Non-Conserved Currents: a Generalization of the
Fermion-Loop Scheme | 48 pages(Latex) | Nucl.Phys. B574 (2000) 451-494 | 10.1016/S0550-3213(00)00010-9 | null | hep-ph | null | A generalization of the Fermion-Loop scheme is introduced to account for
external, non-conserved, currents. Complete Dyson re-summed transitions are
introduced, including the contributions from the Higgs-Kibble ghosts in the 't
Hooft-Feynman gauge. Running vector boson masses are introduced and their
relation with the corresponding complex poles are investigated. It is shown
that any S-matrix element takes a very simple form when written in terms of
these running masses. A special example of Ward identity, the U(1) Ward
identity for single-W, is derived in a situation where all currents are
non-conserved and where the top quark mass is not neglected inside loops.
| [
{
"created": "Thu, 25 Nov 1999 09:12:21 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Passarino",
"G.",
"",
"Turin Univ. and INFN Turin"
]
] | A generalization of the Fermion-Loop scheme is introduced to account for external, non-conserved, currents. Complete Dyson re-summed transitions are introduced, including the contributions from the Higgs-Kibble ghosts in the 't Hooft-Feynman gauge. Running vector boson masses are introduced and their relation with the corresponding complex poles are investigated. It is shown that any S-matrix element takes a very simple form when written in terms of these running masses. A special example of Ward identity, the U(1) Ward identity for single-W, is derived in a situation where all currents are non-conserved and where the top quark mass is not neglected inside loops. |
2105.02474 | Zhi-Long Han | Xu-Hong Bai, Zhi-Long Han, Yi Jin, Hong-Lei Li, Zhao-Xia Meng | Same-Sign Tetralepton Signature in Type-II Seesaw at Lepton Colliders | 12 pages, 5 figures | null | 10.1088/1674-1137/ac2ed1 | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | The same-sign tetralepton signature via mixing of neutral Higgs bosons and
their cascade decays to charged Higgs bosons is a unique signal in the type-II
seesaw model. In this paper, we study this signature at future lepton
colliders, such as ILC, CLIC, and MuC. Constrained by direct search,
$H^{\pm\pm}\to W^\pm W^\pm$ is the only viable decay mode for $M_{A^0}=400$ GeV
at $\sqrt{s}=1$ TeV ILC. With an integrated luminosity of $\mathcal{L}=8~
\mathrm{ab}^{-1}$, the promising region with about 150 signal events
corresponds to a narrow band in the range of $10^{-4}~\text{GeV}\lesssim
v_\Delta \lesssim10^{-2}$ GeV. For heavier triplet scalars $M_{A^0}\gtrsim 900$
GeV, although the $H^{\pm\pm}\to \ell^\pm \ell^\pm$ decay mode is allowed, the
cascade decays are suppressed. A maximum event number $\sim 16$ can be obtained
around $v_\Delta\sim4\times10^{-4}$ GeV and $\lambda_4\sim0.26$ for
$M_{A^0}=1000$ GeV with $\mathcal{L}=5~ \mathrm{ab}^{-1}$ at $\sqrt{s}=3$ TeV
CLIC. Meanwhile, we find that this signature is not promising for
$M_{A^0}=1500$ GeV at $\sqrt{s}=6$ TeV MuC.
| [
{
"created": "Thu, 6 May 2021 07:13:21 GMT",
"version": "v1"
}
] | 2022-01-26 | [
[
"Bai",
"Xu-Hong",
""
],
[
"Han",
"Zhi-Long",
""
],
[
"Jin",
"Yi",
""
],
[
"Li",
"Hong-Lei",
""
],
[
"Meng",
"Zhao-Xia",
""
]
] | The same-sign tetralepton signature via mixing of neutral Higgs bosons and their cascade decays to charged Higgs bosons is a unique signal in the type-II seesaw model. In this paper, we study this signature at future lepton colliders, such as ILC, CLIC, and MuC. Constrained by direct search, $H^{\pm\pm}\to W^\pm W^\pm$ is the only viable decay mode for $M_{A^0}=400$ GeV at $\sqrt{s}=1$ TeV ILC. With an integrated luminosity of $\mathcal{L}=8~ \mathrm{ab}^{-1}$, the promising region with about 150 signal events corresponds to a narrow band in the range of $10^{-4}~\text{GeV}\lesssim v_\Delta \lesssim10^{-2}$ GeV. For heavier triplet scalars $M_{A^0}\gtrsim 900$ GeV, although the $H^{\pm\pm}\to \ell^\pm \ell^\pm$ decay mode is allowed, the cascade decays are suppressed. A maximum event number $\sim 16$ can be obtained around $v_\Delta\sim4\times10^{-4}$ GeV and $\lambda_4\sim0.26$ for $M_{A^0}=1000$ GeV with $\mathcal{L}=5~ \mathrm{ab}^{-1}$ at $\sqrt{s}=3$ TeV CLIC. Meanwhile, we find that this signature is not promising for $M_{A^0}=1500$ GeV at $\sqrt{s}=6$ TeV MuC. |
2107.00658 | Ethan Neil | Daniel C. Hackett and Ethan T. Neil | Soft pion scattering in infrared-conformal gauge-fermion theories | 11 pages, 1 figure. v2: updated to journal version | Phys. Rev. D 106, 016007 (2022) | 10.1103/PhysRevD.106.016007 | MIT-CTP/5311 | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the problem of soft scattering for the analogue of pion states in
gauge-fermion theories which approach a conformal fixed point in the infrared
limit. Introducing a fermion mass into such a theory will explicitly break both
scale invariance and chiral symmetry, leading to confinement and a spectrum of
bound states. We argue that in such a theory, the pion scattering length
diverges in the limit of zero fermion mass, in sharp contrast to QCD-like
theories where the chiral Lagrangian predicts a vanishing scattering length. We
demonstrate this effect both with a simple dimensional argument, and in a
generalized linear sigma model which we argue can be used to describe the
interactions of light scalar and pseudoscalar bound states in the soft limit of
a mass-deformed infrared-conformal theory. As a result, lattice calculations of
pion scattering lengths could be a sensitive probe for infrared scale
invariance in gauge-fermion theories.
| [
{
"created": "Thu, 1 Jul 2021 18:00:01 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Aug 2023 16:03:05 GMT",
"version": "v2"
}
] | 2023-08-09 | [
[
"Hackett",
"Daniel C.",
""
],
[
"Neil",
"Ethan T.",
""
]
] | We consider the problem of soft scattering for the analogue of pion states in gauge-fermion theories which approach a conformal fixed point in the infrared limit. Introducing a fermion mass into such a theory will explicitly break both scale invariance and chiral symmetry, leading to confinement and a spectrum of bound states. We argue that in such a theory, the pion scattering length diverges in the limit of zero fermion mass, in sharp contrast to QCD-like theories where the chiral Lagrangian predicts a vanishing scattering length. We demonstrate this effect both with a simple dimensional argument, and in a generalized linear sigma model which we argue can be used to describe the interactions of light scalar and pseudoscalar bound states in the soft limit of a mass-deformed infrared-conformal theory. As a result, lattice calculations of pion scattering lengths could be a sensitive probe for infrared scale invariance in gauge-fermion theories. |
1610.02659 | Anjan Giri | A. Giri, R. Mohanta and S. Sahoo | Implications of lepton nonuniversality in the beauty sector | 6 pages, 4 figures, talk given at BEACH 2016, George Mason
University, Fairfax, Virginia, USA, June 2016 | null | 10.1088/1742-6596/770/1/012031 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The phenomenon of CP violation in the standard model (SM) framework and the
decay dynamics have been established from the data obtained from the B
factories and so far we have not seen anything new. Nevertheless, there have
been instances of deviations in many measured observables in the flavor sector,
as far as the data and predictions are concerned. Here we will mention some
deviations obtained in measurements related to lepton universality, as seen
from the data, and try to understand their implications. To accommodate the
observed data we will consider a leptoquark model, which seems to be one
interesting model beyond the SM.
| [
{
"created": "Sun, 9 Oct 2016 11:05:39 GMT",
"version": "v1"
}
] | 2017-01-04 | [
[
"Giri",
"A.",
""
],
[
"Mohanta",
"R.",
""
],
[
"Sahoo",
"S.",
""
]
] | The phenomenon of CP violation in the standard model (SM) framework and the decay dynamics have been established from the data obtained from the B factories and so far we have not seen anything new. Nevertheless, there have been instances of deviations in many measured observables in the flavor sector, as far as the data and predictions are concerned. Here we will mention some deviations obtained in measurements related to lepton universality, as seen from the data, and try to understand their implications. To accommodate the observed data we will consider a leptoquark model, which seems to be one interesting model beyond the SM. |
1004.3953 | Francois-Xavier Josse-Michaux | Chiara Arina, Francois-Xavier Josse-Michaux, Narendra Sahu | A Tight Connection Between Direct and Indirect Detection of Dark Matter
through Higgs Portal Couplings to a Hidden Sector | 15 pages, 7 figures. Added discussions on tuning and inverse Compton
scattering constraints. References added and updated. Matches the published
version | Phys.Rev.D82:015005,2010 | 10.1103/PhysRevD.82.015005 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a hidden Abelian extension of the Standard Model including a
complex scalar as a dark matter candidate and a light scalar acting as a long
range force carrier between dark matter particles. The Sommerfeld enhanced
annihilation cross-section of the dark matter explains the observed cosmic ray
excesses. The light scalar field also gives rise to potentially large
cross-sections of dark matter on nucleon, therefore providing an interesting
way to probe this model simultaneously at direct and indirect dark matter
search experiments. We constrain the parameter-space of the model by taking
into account CDMS-II exclusion limit as well as PAMELA and FermiLAT data.
| [
{
"created": "Thu, 22 Apr 2010 16:01:03 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Jul 2010 19:14:27 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Arina",
"Chiara",
""
],
[
"Josse-Michaux",
"Francois-Xavier",
""
],
[
"Sahu",
"Narendra",
""
]
] | We present a hidden Abelian extension of the Standard Model including a complex scalar as a dark matter candidate and a light scalar acting as a long range force carrier between dark matter particles. The Sommerfeld enhanced annihilation cross-section of the dark matter explains the observed cosmic ray excesses. The light scalar field also gives rise to potentially large cross-sections of dark matter on nucleon, therefore providing an interesting way to probe this model simultaneously at direct and indirect dark matter search experiments. We constrain the parameter-space of the model by taking into account CDMS-II exclusion limit as well as PAMELA and FermiLAT data. |
hep-ph/9810498 | Marcio Jose Menon | A.F. Martini, M.J. Menon, J.T.S. Paes and M.J. Silva Neto | Differential dispersion relations and elementary amplitudes in a
multiple diffraction model | 10 pages, aps-revtex, 5 ps figures, one reference and one Comment
added, 2 references updated, minor changes. Final version to be published in
Phys. Rev. D | Phys.Rev. D59 (1999) 116006 | 10.1103/PhysRevD.59.116006 | null | hep-ph hep-th | null | We discuss the evaluation of the real part of the elementary amplitudes in
the context of a multiple diffraction model for $pp$ elastic scattering earlier
developed. The framework is based on the concepts of analyticity and polynomial
boundedness, and the techniques of dispersion relations. Novel results concern
the use of derivative dispersion relations at the elementary level
(constituent-constituent interactions) and an optimization of these relations
in terms of one free parameter. In addition to a theoretical improvement, we
achieved a satisfactory description of the physical quantities.
| [
{
"created": "Tue, 27 Oct 1998 19:37:27 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Mar 1999 19:47:58 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Martini",
"A. F.",
""
],
[
"Menon",
"M. J.",
""
],
[
"Paes",
"J. T. S.",
""
],
[
"Neto",
"M. J. Silva",
""
]
] | We discuss the evaluation of the real part of the elementary amplitudes in the context of a multiple diffraction model for $pp$ elastic scattering earlier developed. The framework is based on the concepts of analyticity and polynomial boundedness, and the techniques of dispersion relations. Novel results concern the use of derivative dispersion relations at the elementary level (constituent-constituent interactions) and an optimization of these relations in terms of one free parameter. In addition to a theoretical improvement, we achieved a satisfactory description of the physical quantities. |
hep-ph/0107208 | Jean-Marc Laget | J.-M. Laget | The photoproduction of vector mesons | 10 pages; 9 figures; Invited talk at the "Third International
Conference on Perspectives in Hadronic Physics", Trieste (Italy), 7--11 May
2001; Nucl. Phys. A, in press | Nucl.Phys. A699 (2002) 184-191 | 10.1016/S0375-9474(01)01492-0 | null | hep-ph | null | At high energy, the photoproduction or electroproduction of Vector Mesons
allow to prepare a beam of quark-antiquark pairs of a given flavor. At high
momentum transfer, the study of the scattering of these pairs on a nucleon
opens up an original window on the quark-gluon structure of hadronic matter,
which may eventually shed light on its gluonic content, on correlations between
quarks and on the van der Walls part of the interaction between hadrons.
| [
{
"created": "Thu, 19 Jul 2001 14:14:52 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Laget",
"J. -M.",
""
]
] | At high energy, the photoproduction or electroproduction of Vector Mesons allow to prepare a beam of quark-antiquark pairs of a given flavor. At high momentum transfer, the study of the scattering of these pairs on a nucleon opens up an original window on the quark-gluon structure of hadronic matter, which may eventually shed light on its gluonic content, on correlations between quarks and on the van der Walls part of the interaction between hadrons. |
1111.3330 | Pedro Machado | P. A. N. Machado, H. Minakata, H. Nunokawa, R. Zukanovich Funchal | Combining Accelerator and Reactor Measurements of theta_13; The First
Result | Final version to be published in JHEP, RENO included, theta13 = 0 is
now rejected at 7.7 sigma CL, 12 pages, 4 figures | null | 10.1007/JHEP05(2012)023 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The lepton mixing angle theta_13, the only unknown angle in the standard
three-flavor neutrino mixing scheme, is finally measured by the recent reactor
and accelerator neutrino experiments. We perform a combined analysis of the
data coming from T2K, MINOS, Double Chooz, Daya Bay and RENO experiments and
find sin^2 2theta_13 = 0.096 \pm 0.013 (\pm 0.040) at 1 sigma (3 sigma) CL and
that the hypothesis theta_13 = 0 is now rejected at a significance level of 7.7
sigma. We also discuss the near future expectation on the precision of the
theta_13 determination by using expected data from these ongoing experiments.
| [
{
"created": "Mon, 14 Nov 2011 19:19:30 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Mar 2012 17:13:58 GMT",
"version": "v2"
},
{
"created": "Wed, 28 Mar 2012 15:32:23 GMT",
"version": "v3"
},
{
"created": "Sat, 28 Apr 2012 08:25:10 GMT",
"version": "v4"
}
] | 2015-06-03 | [
[
"Machado",
"P. A. N.",
""
],
[
"Minakata",
"H.",
""
],
[
"Nunokawa",
"H.",
""
],
[
"Funchal",
"R. Zukanovich",
""
]
] | The lepton mixing angle theta_13, the only unknown angle in the standard three-flavor neutrino mixing scheme, is finally measured by the recent reactor and accelerator neutrino experiments. We perform a combined analysis of the data coming from T2K, MINOS, Double Chooz, Daya Bay and RENO experiments and find sin^2 2theta_13 = 0.096 \pm 0.013 (\pm 0.040) at 1 sigma (3 sigma) CL and that the hypothesis theta_13 = 0 is now rejected at a significance level of 7.7 sigma. We also discuss the near future expectation on the precision of the theta_13 determination by using expected data from these ongoing experiments. |
1905.13101 | Srishti Nagu | Srishti Nagu, Jaydip Singh, Jyotsna Singh and R.B. Singh | Impact of Cross-Sectional Uncertainties on DUNE Sensitivity due to
Nuclear Effects | null | null | 10.1016/j.nuclphysb.2019.114888 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In neutrino oscillation experiments precise measurement of neutrino
oscillation parameters is of prime importance as well as a challenge. To
improve the statistics, presently running and proposed experiments are using
heavy nuclear targets. These targets introduce nuclear effects and the
quantification of these effects on neutrino oscillation parameters will be
decisive in the prediction of neutrino oscillation physics. Limited
understanding of neutrino nucleus interactions and inaccurate reconstruction of
neutrino energy causes uncertainty in the cross section. The error in the
determination of cross section which contributes to systematic error introduces
error in the neutrino mixing parameters that are determined by these
experiments. In this work we focus on the variation in the predictions of DUNE
potential, arising due to systematic uncertainties, using two different event
generators-GENIE and GiBUU. These generators have different and independent
cross-section models. To check the DUNE potential with the two generators as
mentioned we have checked the senstivity studies of DUNE for CP violation, mass
hierarchy and octant degeneracy.
| [
{
"created": "Thu, 23 May 2019 12:08:55 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Jun 2019 06:18:03 GMT",
"version": "v2"
},
{
"created": "Thu, 17 Sep 2020 11:34:49 GMT",
"version": "v3"
}
] | 2020-09-18 | [
[
"Nagu",
"Srishti",
""
],
[
"Singh",
"Jaydip",
""
],
[
"Singh",
"Jyotsna",
""
],
[
"Singh",
"R. B.",
""
]
] | In neutrino oscillation experiments precise measurement of neutrino oscillation parameters is of prime importance as well as a challenge. To improve the statistics, presently running and proposed experiments are using heavy nuclear targets. These targets introduce nuclear effects and the quantification of these effects on neutrino oscillation parameters will be decisive in the prediction of neutrino oscillation physics. Limited understanding of neutrino nucleus interactions and inaccurate reconstruction of neutrino energy causes uncertainty in the cross section. The error in the determination of cross section which contributes to systematic error introduces error in the neutrino mixing parameters that are determined by these experiments. In this work we focus on the variation in the predictions of DUNE potential, arising due to systematic uncertainties, using two different event generators-GENIE and GiBUU. These generators have different and independent cross-section models. To check the DUNE potential with the two generators as mentioned we have checked the senstivity studies of DUNE for CP violation, mass hierarchy and octant degeneracy. |
hep-ph/9512264 | Gregory D. Mahlon | Gregory Mahlon (U. Mich.) and Stephen Parke (FNAL) | Angular Correlations in Top Quark Pair Production and Decay at Hadron
Colliders | 34 pages, revtex, including 12 uuencoded postscript figures | Phys.Rev.D53:4886-4896,1996 | 10.1103/PhysRevD.53.4886 | Fermilab-Pub-95/362-T; UM-TH-95-26 | hep-ph hep-ex | null | We show how to observe sizable angular correlations between the decay
products of the top quark and those of the anti-top quark in top quark pair
production and decay at hadron colliders. These correlations result from the
large asymmetry in the rate for producing like-spin versus unlike-spin top
quark pairs provided the appropriate spin axes are used. The effects of new
physics at production or decay on these correlations are briefly discussed.
| [
{
"created": "Sun, 10 Dec 1995 02:02:23 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Mahlon",
"Gregory",
"",
"U. Mich."
],
[
"Parke",
"Stephen",
"",
"FNAL"
]
] | We show how to observe sizable angular correlations between the decay products of the top quark and those of the anti-top quark in top quark pair production and decay at hadron colliders. These correlations result from the large asymmetry in the rate for producing like-spin versus unlike-spin top quark pairs provided the appropriate spin axes are used. The effects of new physics at production or decay on these correlations are briefly discussed. |
hep-ph/9310368 | Smirnov Alexei | Alexei Yu. Smirnov | Neutrino Masses and Mixing | Talk given at the Int. Conf. "Neutral Currents: Twenty Years Later"
(Paris, July 6 - 9), 15 pages (2 figures available upon request), LaTeX,
IC/93/359 | null | null | null | hep-ph | null | Restrictions on the neutrino masses and lepton mixing are reviewed. Solar,
atmospheric and relic neutrinos give the indications of existence of nonzero
neutrino masses and mixing. The data pick up two regions of mixing angles which
are or appreciably larger or appreciably smaller than the Cabibbo angle. Some
theoretical schemes with {\it large} or {\it small} lepton mixing are
discussed.
| [
{
"created": "Thu, 28 Oct 1993 16:10:48 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Smirnov",
"Alexei Yu.",
""
]
] | Restrictions on the neutrino masses and lepton mixing are reviewed. Solar, atmospheric and relic neutrinos give the indications of existence of nonzero neutrino masses and mixing. The data pick up two regions of mixing angles which are or appreciably larger or appreciably smaller than the Cabibbo angle. Some theoretical schemes with {\it large} or {\it small} lepton mixing are discussed. |
1207.4794 | Keith S. M. Lee | Chien-Yi Chen, Ayres Freitas, Tao Han, and Keith S. M. Lee | New Physics from the Top at the LHC | 19 pages, 7 figures; v2: journal version | JHEP 1211 (2012) 124 | 10.1007/JHEP11(2012)124 | PITT-PACC-1208; CETUP*-12/001 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The top quark may hold the key to new physics associated with the electroweak
symmetry-breaking sector, given its large mass and enhanced coupling to the
Higgs sector. We systematically categorize generic interactions of a new
particle that couples to the top quark and a neutral particle, which is assumed
to be heavy and stable, thus serving as a candidate for cold dark matter. The
experimental signatures for new physics involving top quarks and its partners
at the Large Hadron Collider (LHC) may be distinctive, yet challenging to
disentangle. We optimize the search strategy at the LHC for the decay of the
new particle to a top quark plus missing energy and propose the study of its
properties, such as its spin and couplings. We find that, at 14 TeV with an
integrated luminosity of 100 fb^-1, a spin-zero top partner can be observed at
the 5-sigma level for a mass of 675 GeV. A spin-zero particle can be
differentiated from spin-1/2 and spin-1 particles at the 5-sigma level with a
luminosity of 10 fb^-1.
| [
{
"created": "Thu, 19 Jul 2012 20:00:10 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Dec 2012 20:58:50 GMT",
"version": "v2"
}
] | 2012-12-11 | [
[
"Chen",
"Chien-Yi",
""
],
[
"Freitas",
"Ayres",
""
],
[
"Han",
"Tao",
""
],
[
"Lee",
"Keith S. M.",
""
]
] | The top quark may hold the key to new physics associated with the electroweak symmetry-breaking sector, given its large mass and enhanced coupling to the Higgs sector. We systematically categorize generic interactions of a new particle that couples to the top quark and a neutral particle, which is assumed to be heavy and stable, thus serving as a candidate for cold dark matter. The experimental signatures for new physics involving top quarks and its partners at the Large Hadron Collider (LHC) may be distinctive, yet challenging to disentangle. We optimize the search strategy at the LHC for the decay of the new particle to a top quark plus missing energy and propose the study of its properties, such as its spin and couplings. We find that, at 14 TeV with an integrated luminosity of 100 fb^-1, a spin-zero top partner can be observed at the 5-sigma level for a mass of 675 GeV. A spin-zero particle can be differentiated from spin-1/2 and spin-1 particles at the 5-sigma level with a luminosity of 10 fb^-1. |
hep-ph/0408162 | Pawel Moskal | P. Moskal (Jagellonian U.) | Hadronic interaction of eta and eta-prime mesons with protons | Thesis for the postdoctoral lecture qualification, format B5, 145
pages | Jagiellonian University Press (2004) ISBN 83-233-1889-1 | null | null | hep-ph | null | We present results of investigations aiming to determine the hadronic
interaction of eta and eta-prime mesons with nucleons. Inferences are based on
comparisons of both the differential cross sections and the close-to-threshold
excitation functions for the p p --> p p eta and p p --> p p eta-prime
reactions with predictions based on the assumption that the kinematically
available phase space is homogeneously populated. We discuss the phenomenology
of the initial and final state interaction, relevance of the hadronic and
quark-gluon degrees of freedom for the reaction dynamics, and explain in detail
the experimental techniques used for the measurement of the meson production in
free and quasi-free collisions of nucleons.
| [
{
"created": "Sun, 15 Aug 2004 00:54:23 GMT",
"version": "v1"
}
] | 2009-09-29 | [
[
"Moskal",
"P.",
"",
"Jagellonian U."
]
] | We present results of investigations aiming to determine the hadronic interaction of eta and eta-prime mesons with nucleons. Inferences are based on comparisons of both the differential cross sections and the close-to-threshold excitation functions for the p p --> p p eta and p p --> p p eta-prime reactions with predictions based on the assumption that the kinematically available phase space is homogeneously populated. We discuss the phenomenology of the initial and final state interaction, relevance of the hadronic and quark-gluon degrees of freedom for the reaction dynamics, and explain in detail the experimental techniques used for the measurement of the meson production in free and quasi-free collisions of nucleons. |
2309.07884 | Bernhard Mistlberger | Franz Herzog, Yao Ma, Bernhard Mistlberger, Adi Suresh | Single-soft emissions for amplitudes with two colored particles at three
loops | 29 pages, 2 Figures | null | null | SLAC-PUB-17742 | hep-ph hep-th | http://creativecommons.org/licenses/by/4.0/ | We compute the three-loop correction to the universal single-soft emission
current for the case of scattering amplitudes with two additional color-charged
partons. We present results valid for QCD and $\mathcal{N}=4$ super-symmetric
Yang-Mills theory. To achieve our results we develop a new integrand expansion
technique for scattering amplitudes in the presence of soft emissions.
Furthermore, we obtain contributions from single final-state parton matrix
elements to the Higgs boson and Drell-Yan production cross section at
next-to-next-to-next-to-next-to leading order (N$^4$LO) in perturbative QCD in
the threshold limit.
| [
{
"created": "Thu, 14 Sep 2023 17:30:41 GMT",
"version": "v1"
}
] | 2023-09-15 | [
[
"Herzog",
"Franz",
""
],
[
"Ma",
"Yao",
""
],
[
"Mistlberger",
"Bernhard",
""
],
[
"Suresh",
"Adi",
""
]
] | We compute the three-loop correction to the universal single-soft emission current for the case of scattering amplitudes with two additional color-charged partons. We present results valid for QCD and $\mathcal{N}=4$ super-symmetric Yang-Mills theory. To achieve our results we develop a new integrand expansion technique for scattering amplitudes in the presence of soft emissions. Furthermore, we obtain contributions from single final-state parton matrix elements to the Higgs boson and Drell-Yan production cross section at next-to-next-to-next-to-next-to leading order (N$^4$LO) in perturbative QCD in the threshold limit. |
1703.05809 | Matthew Sievert | Yuri V. Kovchegov, Daniel Pitonyak, and Matthew D. Sievert | Small-$x$ Asymptotics of the Quark Helicity Distribution: Analytic
Results | 5 pages, 2 figures | null | 10.1016/j.physletb.2017.06.032 | LA-UR-17-22988 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this Letter, we analytically solve the evolution equations for the
small-$x$ asymptotic behavior of the (flavor singlet) quark helicity
distribution in the large-$N_c$ limit. These evolution equations form a set of
coupled integro-differential equations, which previously could only be solved
numerically. This approximate numerical solution, however, revealed simplifying
properties of the small-$x$ asymptotics, which we exploit here to obtain an
analytic solution. We find that the small-$x$ power-law tail of the quark
helicity distribution scales as $\Delta q^S (x, Q^2) \sim \left(\tfrac{1}{x}
\right)^{\alpha_h}$ with $\alpha_h = \tfrac{4}{\sqrt{3}} \sqrt{\tfrac{\alpha_s
N_c}{2\pi}}$, in excellent agreement with the numerical estimate $\alpha_h
\approx 2.31\sqrt{\tfrac{\alpha_s N_c}{2\pi}}$ obtained previously. We then
verify this solution by cross-checking the predicted scaling behavior of the
auxiliary "neighbor dipole amplitude" against the numerics, again finding
excellent agreement.
| [
{
"created": "Thu, 16 Mar 2017 19:55:34 GMT",
"version": "v1"
}
] | 2017-06-21 | [
[
"Kovchegov",
"Yuri V.",
""
],
[
"Pitonyak",
"Daniel",
""
],
[
"Sievert",
"Matthew D.",
""
]
] | In this Letter, we analytically solve the evolution equations for the small-$x$ asymptotic behavior of the (flavor singlet) quark helicity distribution in the large-$N_c$ limit. These evolution equations form a set of coupled integro-differential equations, which previously could only be solved numerically. This approximate numerical solution, however, revealed simplifying properties of the small-$x$ asymptotics, which we exploit here to obtain an analytic solution. We find that the small-$x$ power-law tail of the quark helicity distribution scales as $\Delta q^S (x, Q^2) \sim \left(\tfrac{1}{x} \right)^{\alpha_h}$ with $\alpha_h = \tfrac{4}{\sqrt{3}} \sqrt{\tfrac{\alpha_s N_c}{2\pi}}$, in excellent agreement with the numerical estimate $\alpha_h \approx 2.31\sqrt{\tfrac{\alpha_s N_c}{2\pi}}$ obtained previously. We then verify this solution by cross-checking the predicted scaling behavior of the auxiliary "neighbor dipole amplitude" against the numerics, again finding excellent agreement. |
hep-ph/9810452 | S. Schmidt | S. Schmidt, D. Blaschke, G. Ropke, A.V. Prozorkevich, S.A. Smolyansky,
V.D. Toneev | Non-Markovian effects in strong-field pair creation | 11 pages, revteX, epsfig.sty, 6 figures | Phys. Rev. D 59, 094005 (1999) | 10.1103/PhysRevD.59.094005 | MPG-VT-UR 166/98 | hep-ph | null | We analyze a quantum kinetic equation describing both boson and fermion pair
production and explore analytically and numerically the solution of the
non-Markovian kinetic equation. In the Markovian limit of the kinetic equation
we find an analytical solution for the single particle distribution function of
bosons and fermions. The numerical investigation for a homogeneous, constant
electric field shows an enhancement (bosons) or a suppression (fermions) of the
pair creation rate according to the symmetry character of the produced
particles. For strong fields non-Markovian effects are important while they
disappear for weak fields. Hence it is sufficient to apply the low density
limit for weak fields but necessary to take into account memory effects for
strong fields.
| [
{
"created": "Thu, 22 Oct 1998 13:16:19 GMT",
"version": "v1"
}
] | 2016-08-25 | [
[
"Schmidt",
"S.",
""
],
[
"Blaschke",
"D.",
""
],
[
"Ropke",
"G.",
""
],
[
"Prozorkevich",
"A. V.",
""
],
[
"Smolyansky",
"S. A.",
""
],
[
"Toneev",
"V. D.",
""
]
] | We analyze a quantum kinetic equation describing both boson and fermion pair production and explore analytically and numerically the solution of the non-Markovian kinetic equation. In the Markovian limit of the kinetic equation we find an analytical solution for the single particle distribution function of bosons and fermions. The numerical investigation for a homogeneous, constant electric field shows an enhancement (bosons) or a suppression (fermions) of the pair creation rate according to the symmetry character of the produced particles. For strong fields non-Markovian effects are important while they disappear for weak fields. Hence it is sufficient to apply the low density limit for weak fields but necessary to take into account memory effects for strong fields. |
1906.11522 | Igor Anikin | I.V. Anikin | Estimation of nucleon D-term in QCD | 6 pages, 2 figures; The Special Issue "QCD and Hadron Structure"
devoted to the memory of Prof. G.V. Efimov. arXiv admin note: substantial
text overlap with arXiv:1902.00094 | Particles 2019, 2(3), 357-364;
https://doi.org/10.3390/particles2030022 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the light-cone sum rules at leading order, we present an approach to
perform the preliminary upper estimation for the nucleon gravitational form
factor $D(t)$ ($D$-term contribution). Comparison with the experimental data
and with the results of different models is discussed.
| [
{
"created": "Thu, 27 Jun 2019 09:48:06 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Jul 2019 14:36:16 GMT",
"version": "v2"
}
] | 2019-07-04 | [
[
"Anikin",
"I. V.",
""
]
] | Using the light-cone sum rules at leading order, we present an approach to perform the preliminary upper estimation for the nucleon gravitational form factor $D(t)$ ($D$-term contribution). Comparison with the experimental data and with the results of different models is discussed. |
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