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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1108.3220 | Krzysztof Rolbiecki | O. Kittel, G. Moortgat-Pick, K. Rolbiecki, P. Schade, and M. Terwort | Measurement of CP asymmetries in neutralino production at the ILC | 27 pages, 5 figures, minor changes, to appear in the EPJC | null | 10.1140/epjc/s10052-011-1854-4 | DESY-11-105 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the prospects to measure the CP-sensitive triple-product asymmetries
in neutralino production e+e- -> ~chi^0_i ~chi^0_1 and subsequent leptonic
two-body decays ~chi^0_i -> ~l_R l, ~l_R -> ~chi^0_1 l, for l=e, mu, within the
Minimal Supersymmetric Standard Model. We include a full detector simulation of
the International Large Detector for the International Linear Collider. The
simulation was performed at a center-of-mass energy of sqrt{s}=500 GeV,
including the relevant Standard Model background processes, a realistic beam
energy spectrum, beam backgrounds and a beam polarization of 80% and -60% for
the electron and positron beams, respectively. In order to effectively
disentangle different signal samples and reduce SM and SUSY backgrounds we
apply a method of kinematic reconstruction. Assuming an integrated luminosity
of 500 fb^-1 collected by the experiment and the performance of the current ILD
detector, we arrive at a relative measurement accuracy of 10% for the
CP-sensitive asymmetry in our scenario. We demonstrate that our method of
signal selection using kinematic reconstruction can be applied to a broad class
of scenarios and it allows disentangling processes with similar kinematic
properties.
| [
{
"created": "Tue, 16 Aug 2011 12:20:26 GMT",
"version": "v1"
},
{
"created": "Thu, 26 Jan 2012 16:15:07 GMT",
"version": "v2"
}
] | 2015-05-30 | [
[
"Kittel",
"O.",
""
],
[
"Moortgat-Pick",
"G.",
""
],
[
"Rolbiecki",
"K.",
""
],
[
"Schade",
"P.",
""
],
[
"Terwort",
"M.",
""
]
] | We study the prospects to measure the CP-sensitive triple-product asymmetries in neutralino production e+e- -> ~chi^0_i ~chi^0_1 and subsequent leptonic two-body decays ~chi^0_i -> ~l_R l, ~l_R -> ~chi^0_1 l, for l=e, mu, within the Minimal Supersymmetric Standard Model. We include a full detector simulation of the International Large Detector for the International Linear Collider. The simulation was performed at a center-of-mass energy of sqrt{s}=500 GeV, including the relevant Standard Model background processes, a realistic beam energy spectrum, beam backgrounds and a beam polarization of 80% and -60% for the electron and positron beams, respectively. In order to effectively disentangle different signal samples and reduce SM and SUSY backgrounds we apply a method of kinematic reconstruction. Assuming an integrated luminosity of 500 fb^-1 collected by the experiment and the performance of the current ILD detector, we arrive at a relative measurement accuracy of 10% for the CP-sensitive asymmetry in our scenario. We demonstrate that our method of signal selection using kinematic reconstruction can be applied to a broad class of scenarios and it allows disentangling processes with similar kinematic properties. |
hep-ph/9504325 | Carleton Detar | Carleton DeTar | Quark Gluon Plasma from Numerical Simulations of Lattice QCD | Review article to appear in Quark Gluon Plasma 2, edited by R. Hwa,
World Scientific, 1995. 50 pp in one Postscript file, gz-compressed,
uuencoded | null | 10.1142/9789812830661_0001 | UUHEP 95/2 | hep-ph hep-lat nucl-th | null | Numerical simulations of quantum chromodynamics at nonzero temperature
provide information from first principles about the physical properties of the
quark gluon plasma. Because the lattice approximation can be refined
indefinitely, results of lattice simulations now provide the most reliable
basis for our understanding of the nonperturbative characteristics of the
plasma and of the high temperature phase transition. Following a brief overview
of the methodology of lattice gauge theory at nonzero temperature, recent
results and insights from lattice simulations are discussed. These include our
understanding of the phase diagram of QCD, the nature of the phase transition,
and the structure of the plasma.
| [
{
"created": "Tue, 18 Apr 1995 20:23:32 GMT",
"version": "v1"
}
] | 2016-11-03 | [
[
"DeTar",
"Carleton",
""
]
] | Numerical simulations of quantum chromodynamics at nonzero temperature provide information from first principles about the physical properties of the quark gluon plasma. Because the lattice approximation can be refined indefinitely, results of lattice simulations now provide the most reliable basis for our understanding of the nonperturbative characteristics of the plasma and of the high temperature phase transition. Following a brief overview of the methodology of lattice gauge theory at nonzero temperature, recent results and insights from lattice simulations are discussed. These include our understanding of the phase diagram of QCD, the nature of the phase transition, and the structure of the plasma. |
0908.1554 | Antonio Pich | Antonio Pich and Paula Tuzon | Yukawa Alignment in the Two-Higgs-Doublet Model | null | Phys.Rev.D80:091702,2009 | 10.1103/PhysRevD.80.091702 | IFIC/09-36, FTUV/09-0810 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In multi-Higgs-doublet models the alignment in flavour space of the relevant
Yukawa matrices guarantees the absence of tree-level flavour-changing couplings
of the neutral scalar fields. We analyze the consequences of this condition
within the two-Higgs-doublet model and show that it leads to a generic Yukawa
structure which contains as particular cases all known specific implementations
of the model based on Z_2 symmetries. All possible freedom in the Yukawa sector
gets parametrized in terms of three complex couplings. In spite of having
flavour conservation in the neutral scalar couplings, the phases of these three
parameters represent potential new sources of CP violation.
| [
{
"created": "Tue, 11 Aug 2009 18:58:25 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Nov 2009 22:21:19 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Pich",
"Antonio",
""
],
[
"Tuzon",
"Paula",
""
]
] | In multi-Higgs-doublet models the alignment in flavour space of the relevant Yukawa matrices guarantees the absence of tree-level flavour-changing couplings of the neutral scalar fields. We analyze the consequences of this condition within the two-Higgs-doublet model and show that it leads to a generic Yukawa structure which contains as particular cases all known specific implementations of the model based on Z_2 symmetries. All possible freedom in the Yukawa sector gets parametrized in terms of three complex couplings. In spite of having flavour conservation in the neutral scalar couplings, the phases of these three parameters represent potential new sources of CP violation. |
0705.4648 | Frank Krauss | Tanju Gleisberg, Stefan Hoeche, Frank Krauss, Radoslaw Matyszkiewicz,
Marek Schoenherr, Steffen Schumann, Frank Siegert, Jan Winter | New trends in modern event generators | 4 pages, talk given by Frank Krauss at Moriond 2007, QCD session | null | null | null | hep-ph | null | Some features of modern simulation tools for high-energy physics are
reviewed.
| [
{
"created": "Thu, 31 May 2007 17:21:49 GMT",
"version": "v1"
}
] | 2007-06-01 | [
[
"Gleisberg",
"Tanju",
""
],
[
"Hoeche",
"Stefan",
""
],
[
"Krauss",
"Frank",
""
],
[
"Matyszkiewicz",
"Radoslaw",
""
],
[
"Schoenherr",
"Marek",
""
],
[
"Schumann",
"Steffen",
""
],
[
"Siegert",
"Frank",
""... | Some features of modern simulation tools for high-energy physics are reviewed. |
0907.1628 | Shao-Long Chen | Shmuel Nussinov | Dark Matter Tomography | 6 pages, 1 figure | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider Wimp annihilations into monochromatic and continuous $\gamma$'s
and the angular distribution of the resulting gammas. We discuss how the WIMP
density profile can be reconstructed from the angular dependence of the photon
flux.
| [
{
"created": "Thu, 9 Jul 2009 17:30:06 GMT",
"version": "v1"
}
] | 2009-07-10 | [
[
"Nussinov",
"Shmuel",
""
]
] | We consider Wimp annihilations into monochromatic and continuous $\gamma$'s and the angular distribution of the resulting gammas. We discuss how the WIMP density profile can be reconstructed from the angular dependence of the photon flux. |
2008.01095 | Dorin Weissman | Jacob Sonnenschein and Dorin Weissman | Deciphering the recently discovered tetraquark candidates around 6.9 GeV | v1: 22 pages, 4 figures v2: typos corrected, minor additions and
references added. 22 pages, v3: references added. 22 pages | Eur. Phys. J. C 81, 25 (2021) | 10.1140/epjc/s10052-020-08818-7 | null | hep-ph hep-ex hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently a novel hadronic state of mass 6.9 GeV, that decays mainly to a pair
of charmonia, was observed in LHCb. The data also reveals a broader structure
centered around 6490 MeV and suggests another unconfirmed resonance centered at
around 7240 MeV, very near to the threshold of two doubly charmed $\Xi_{cc}$
baryons. We argue in this note that these exotic hadrons are genuine
tetraquarks and not molecules of charmonia. It is conjectured that they are
V-baryonium tetraquarks, namely, have an inner structure of a baryonic vertex
with a $cc$ diquark attached to it, which is connected by a string to an
anti-baryonic vertex with a $\bar c \bar c$ anti-diquark. We examine these
states as the analogs of the states $\Psi(4360)$ and $Y(4630)$/$\Psi(4660)$
which are charmonium-like tetraquarks. One way to test these claims is by
searching for a significant decay of the state at 7.2 GeV into
$\Xi_{cc}\overline\Xi_{cc}$. Such a decay would be the analog of the decay of
the state $Y(4630)$ into to $\Lambda_c\overline\Lambda_c$. We further argue
that there should be trajectories of both orbital and radial excited states of
the $X(6900)$. We predict their masses. It is possible that a few of these
states have already been seen by LHCb.
| [
{
"created": "Mon, 3 Aug 2020 18:00:04 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Sep 2020 03:18:35 GMT",
"version": "v2"
},
{
"created": "Tue, 13 Oct 2020 14:25:06 GMT",
"version": "v3"
}
] | 2021-01-19 | [
[
"Sonnenschein",
"Jacob",
""
],
[
"Weissman",
"Dorin",
""
]
] | Recently a novel hadronic state of mass 6.9 GeV, that decays mainly to a pair of charmonia, was observed in LHCb. The data also reveals a broader structure centered around 6490 MeV and suggests another unconfirmed resonance centered at around 7240 MeV, very near to the threshold of two doubly charmed $\Xi_{cc}$ baryons. We argue in this note that these exotic hadrons are genuine tetraquarks and not molecules of charmonia. It is conjectured that they are V-baryonium tetraquarks, namely, have an inner structure of a baryonic vertex with a $cc$ diquark attached to it, which is connected by a string to an anti-baryonic vertex with a $\bar c \bar c$ anti-diquark. We examine these states as the analogs of the states $\Psi(4360)$ and $Y(4630)$/$\Psi(4660)$ which are charmonium-like tetraquarks. One way to test these claims is by searching for a significant decay of the state at 7.2 GeV into $\Xi_{cc}\overline\Xi_{cc}$. Such a decay would be the analog of the decay of the state $Y(4630)$ into to $\Lambda_c\overline\Lambda_c$. We further argue that there should be trajectories of both orbital and radial excited states of the $X(6900)$. We predict their masses. It is possible that a few of these states have already been seen by LHCb. |
1101.5548 | Daniel Litim | Erik Gerwick, Daniel Litim, Tilman Plehn | Asymptotic safety and Kaluza-Klein gravitons at the LHC | 25 pages, 14 figures | Phys.Rev.D83:084048,2011 | 10.1103/PhysRevD.83.084048 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study Drell-Yan production at the LHC in low-scale quantum gravity models
with extra dimensions. Asymptotic safety implies that the ultra-violet behavior
of gravity is dictated by a fixed point. We show how the energy dependence of
Newton's coupling regularizes the gravitational amplitude using a
renormalization group improvement. We study LHC predictions and find that
Kaluza-Klein graviton signals are well above Standard Model backgrounds. This
leaves a significant sensitivity to the energy scale Lambda_T where the
gravitational couplings cross over from classical to fixed point scaling.
| [
{
"created": "Fri, 28 Jan 2011 15:14:20 GMT",
"version": "v1"
}
] | 2011-05-12 | [
[
"Gerwick",
"Erik",
""
],
[
"Litim",
"Daniel",
""
],
[
"Plehn",
"Tilman",
""
]
] | We study Drell-Yan production at the LHC in low-scale quantum gravity models with extra dimensions. Asymptotic safety implies that the ultra-violet behavior of gravity is dictated by a fixed point. We show how the energy dependence of Newton's coupling regularizes the gravitational amplitude using a renormalization group improvement. We study LHC predictions and find that Kaluza-Klein graviton signals are well above Standard Model backgrounds. This leaves a significant sensitivity to the energy scale Lambda_T where the gravitational couplings cross over from classical to fixed point scaling. |
0810.2498 | Helen Matskevich | S.M. Gerasyuta and V.I. Kochkin | Widths of tetraquarks with open charm | 8 pages, latex | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of coupled-channel formalism the relativistic four-quark
equations are found. The dynamical mixing of the meson-meson states with the
four-quark states is considered. The four-quark amplitudes of the tetraquarks
with open charm, including u, d, s, c quarks, are constructed. The poles of
these amplitudes determine the masses and widths of tetraquarks.
| [
{
"created": "Tue, 14 Oct 2008 17:04:13 GMT",
"version": "v1"
}
] | 2008-11-04 | [
[
"Gerasyuta",
"S. M.",
""
],
[
"Kochkin",
"V. I.",
""
]
] | In the framework of coupled-channel formalism the relativistic four-quark equations are found. The dynamical mixing of the meson-meson states with the four-quark states is considered. The four-quark amplitudes of the tetraquarks with open charm, including u, d, s, c quarks, are constructed. The poles of these amplitudes determine the masses and widths of tetraquarks. |
2012.08901 | Adil Jueid | Simone Amoroso, Sascha Caron, Adil Jueid, Roberto Ruiz de Austri,
Peter Skands | Particle spectra from dark matter annihilation: physics modeling and QCD
uncertainties | 14 pages, 5 figures, Contribution for the talk presented in Tools for
High Energy Physics and Cosmology workshop (TOOLS2020), 2-6 November 2020,
IP2I Lyon, France. Based on arXiv:1812.07424. Relevant data can be found on
Zenodo (http://doi.org/10.5281/zenodo.3764809) | null | null | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | In this talk, we discuss the physics modelling of particle spectra arising
from dark matter (DM) annihilation or decay. In the context of the indirect
searches of DM, the final state products will, in general, undergo a set of
complicated processes such as resonance decays, QED/QCD radiation,
hadronisation and hadron decays. This set of processes lead to stable particles
(photons, positrons, anti-protons, and neutrinos among others) which travel for
very long distances before reaching the detectors. The modelling of their
spectra contains some uncertainties which are often neglected in the relevant
analyses. We discuss the sources of these uncertainties and estimate their
impact on photon energy spectra for benchmark DM scenarios with $m_\chi \in
[10, 1000]\,$GeV. Instructions for how to retrieve complete tables from Zenodo
are also provided.
| [
{
"created": "Wed, 16 Dec 2020 12:24:13 GMT",
"version": "v1"
}
] | 2020-12-17 | [
[
"Amoroso",
"Simone",
""
],
[
"Caron",
"Sascha",
""
],
[
"Jueid",
"Adil",
""
],
[
"de Austri",
"Roberto Ruiz",
""
],
[
"Skands",
"Peter",
""
]
] | In this talk, we discuss the physics modelling of particle spectra arising from dark matter (DM) annihilation or decay. In the context of the indirect searches of DM, the final state products will, in general, undergo a set of complicated processes such as resonance decays, QED/QCD radiation, hadronisation and hadron decays. This set of processes lead to stable particles (photons, positrons, anti-protons, and neutrinos among others) which travel for very long distances before reaching the detectors. The modelling of their spectra contains some uncertainties which are often neglected in the relevant analyses. We discuss the sources of these uncertainties and estimate their impact on photon energy spectra for benchmark DM scenarios with $m_\chi \in [10, 1000]\,$GeV. Instructions for how to retrieve complete tables from Zenodo are also provided. |
1211.7004 | Carlos Hidalgo-Duque | C. Hidalgo-Duque, J. Nieves and M. Pav\'on Valderrama | Heavy Quark Spin Symmetry and SU(3)-Flavour Partners of the X(3872) | 4 pages, 0 figures. arXiv admin note: text overlap with
arXiv:1210.5431 | null | 10.1016/j.nuclphysa.2013.01.025 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, an Effective Field Theory (EFT) incorporating light
SU(3)-flavour and heavy quark spin symmetry is used to describe charmed
meson-antimeson bound states. At Lowest Order (LO), this means that only
contact range interactions among the heavy meson and antimeson fields are
involved. Besides, the isospin violating decays of the X(3872) will be used to
constrain the interaction between the $D$ and a $\bar{D}^*$ mesons in the
isovector channel. Finally, assuming that the X(3915) and Y(4140) resonances
are $D^*\bar{D}^*$ and $D_s^*\bar{D}_s^*$ molecular states, we can determine
the four Low Energy Constants (LECs) of the EFT that appear at LO and,
therefore, the full spectrum of molecular states with isospin I=0, 1/2 and 1.
| [
{
"created": "Thu, 29 Nov 2012 17:52:00 GMT",
"version": "v1"
}
] | 2013-09-30 | [
[
"Hidalgo-Duque",
"C.",
""
],
[
"Nieves",
"J.",
""
],
[
"Valderrama",
"M. Pavón",
""
]
] | In this work, an Effective Field Theory (EFT) incorporating light SU(3)-flavour and heavy quark spin symmetry is used to describe charmed meson-antimeson bound states. At Lowest Order (LO), this means that only contact range interactions among the heavy meson and antimeson fields are involved. Besides, the isospin violating decays of the X(3872) will be used to constrain the interaction between the $D$ and a $\bar{D}^*$ mesons in the isovector channel. Finally, assuming that the X(3915) and Y(4140) resonances are $D^*\bar{D}^*$ and $D_s^*\bar{D}_s^*$ molecular states, we can determine the four Low Energy Constants (LECs) of the EFT that appear at LO and, therefore, the full spectrum of molecular states with isospin I=0, 1/2 and 1. |
hep-ph/9401201 | Carsten Grosse-Knetter | Carsten Grosse-Knetter (Universitaet Bielefeld) | Nonstandard Quartic Self Interactions of Electroweak Vector Bosons
within a Gauge Invariant Higher-Derivative Term | BI-TP 94/01, 6 pages LaTeX | null | null | null | hep-ph | null | A locally SU(2)xU(1)-invariant term of dimension six with effective
interactions of the electroweak gauge and Higgs fields is examined. This term
also contains higher derivatives of the fields. It yields nonstandard quartic
gauge-boson self-interactions but neither nonstandard cubic self-interactions
nor tree-level effects on presently measurable quantities.
| [
{
"created": "Mon, 3 Jan 1994 08:47:32 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Grosse-Knetter",
"Carsten",
"",
"Universitaet Bielefeld"
]
] | A locally SU(2)xU(1)-invariant term of dimension six with effective interactions of the electroweak gauge and Higgs fields is examined. This term also contains higher derivatives of the fields. It yields nonstandard quartic gauge-boson self-interactions but neither nonstandard cubic self-interactions nor tree-level effects on presently measurable quantities. |
0808.2767 | Peter Arnold | Peter Arnold | Simple Formula for High-Energy Gluon Bremsstrahlung in a Finite,
Expanding Medium | 25 pages, 1 figure [changes from v1: clarifications made as to range
of validity of results for small medium size] | Phys.Rev.D79:065025,2009 | 10.1103/PhysRevD.79.065025 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Previous authors have considered the problem of the medium effects on single
gluon bremsstrahlung associated with producing a high-energy particle in a
finite, time-dependent QCD plasma. Working to leading logarithmic order, I show
that the result for the bremsstrahlung gluon spectrum can be cast into a
remarkably simple form in the general case. I similarly analyze the process of
pair production. Also, I comment on the radius of convergence of the opacity
expansion in cases where the leading-log approximation holds, showing that the
opacity expansion does not converge when the thickness of the plasma is greater
than roughly the bremsstrahlung formation time. Additionally, as a special
bonus -- available for a limited time only while supplies last! -- I summarize
translations between the notation used by a few of the groups who have worked
on this and related problems.
| [
{
"created": "Wed, 20 Aug 2008 17:27:35 GMT",
"version": "v1"
},
{
"created": "Thu, 5 Mar 2009 21:46:19 GMT",
"version": "v2"
}
] | 2009-11-06 | [
[
"Arnold",
"Peter",
""
]
] | Previous authors have considered the problem of the medium effects on single gluon bremsstrahlung associated with producing a high-energy particle in a finite, time-dependent QCD plasma. Working to leading logarithmic order, I show that the result for the bremsstrahlung gluon spectrum can be cast into a remarkably simple form in the general case. I similarly analyze the process of pair production. Also, I comment on the radius of convergence of the opacity expansion in cases where the leading-log approximation holds, showing that the opacity expansion does not converge when the thickness of the plasma is greater than roughly the bremsstrahlung formation time. Additionally, as a special bonus -- available for a limited time only while supplies last! -- I summarize translations between the notation used by a few of the groups who have worked on this and related problems. |
1807.11319 | Ayon Mukherjee | Ayon Mukherjee, Abhijit Bhattacharyya, Stefan Schramm | Effects of a non-zero strangeness-chemical potential in strong
interaction models | 8 pages, 13 figures | null | 10.1016/j.physletb.2019.134899 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The effect of a non-zero strangeness chemical potential on the strong
interaction phase diagram has been studied within the framework of the SU(3)
quark-hadron chiral parity-doublet model. Both, the nuclear liquid-gas and the
chiral/deconfinement phase transitions are modified. The first-order line in
the chiral phase transition is observed to vanish completely, with the entire
phase boundary becoming a crossover. These changes in the nature of the phase
transitions are expected to modify various susceptibilities, the effects of
which might be detectable in particle-number distributions resulting from
moderate-temperature and high-density heavy-ion collision experiments.
| [
{
"created": "Mon, 30 Jul 2018 12:42:00 GMT",
"version": "v1"
}
] | 2019-09-04 | [
[
"Mukherjee",
"Ayon",
""
],
[
"Bhattacharyya",
"Abhijit",
""
],
[
"Schramm",
"Stefan",
""
]
] | The effect of a non-zero strangeness chemical potential on the strong interaction phase diagram has been studied within the framework of the SU(3) quark-hadron chiral parity-doublet model. Both, the nuclear liquid-gas and the chiral/deconfinement phase transitions are modified. The first-order line in the chiral phase transition is observed to vanish completely, with the entire phase boundary becoming a crossover. These changes in the nature of the phase transitions are expected to modify various susceptibilities, the effects of which might be detectable in particle-number distributions resulting from moderate-temperature and high-density heavy-ion collision experiments. |
2312.10140 | Stefan Schacht | Margarita Gavrilova, Yuval Grossman, Stefan Schacht | Determination of the $D\rightarrow \pi\pi$ ratio of penguin over tree
diagrams | 9 pages. Matches published version | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We study the penguin over tree ratio in $D\rightarrow \pi\pi$ decays. This
ratio can serve as a probe for rescattering effects. Assuming the Standard
Model and in the isospin limit, we derive expressions that relate both the
magnitude and the phase of this ratio to direct CP asymmetries and branching
fractions. We find that the current data suggest that rescattering is large. A
dedicated experimental analysis with current and future data will be able to
significantly reduce the errors on these determinations, and enable us to check
if indeed there is significant rescattering in $D \to \pi \pi$ decays.
| [
{
"created": "Fri, 15 Dec 2023 19:00:02 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Feb 2024 09:14:03 GMT",
"version": "v2"
}
] | 2024-03-01 | [
[
"Gavrilova",
"Margarita",
""
],
[
"Grossman",
"Yuval",
""
],
[
"Schacht",
"Stefan",
""
]
] | We study the penguin over tree ratio in $D\rightarrow \pi\pi$ decays. This ratio can serve as a probe for rescattering effects. Assuming the Standard Model and in the isospin limit, we derive expressions that relate both the magnitude and the phase of this ratio to direct CP asymmetries and branching fractions. We find that the current data suggest that rescattering is large. A dedicated experimental analysis with current and future data will be able to significantly reduce the errors on these determinations, and enable us to check if indeed there is significant rescattering in $D \to \pi \pi$ decays. |
hep-ph/0509325 | Jacques Soffer | Jacques Soffer | A new search strategy for the Higgs boson | 4 pages, 1 figure, Talk presented at the International Conference on
QCD and Hadronic Physics, Beijing, June 16-20 (2005) | Int.J.Mod.Phys. A21 (2006) 934-937 | 10.1142/S0217751X06032356 | CPT-2005/P.044 | hep-ph | null | We propose a novel mechanism for exclusive diffractive Higgs production $pp
\to Hpp$, in which the Higgs carries a significant fraction of the projectile
proton's momentum. This mechanism will then provide a clear experimental signal
for Higgs production, due to the small background in this kinematic region. The
key assumption underlying our analysis is the presence of intrinsic charm (IC)
and intrinsic bottom (IB) fluctuations in the proton bound state, whose
existence, at high light-cone momentum fraction $x$, has a substantial and
growing experimental and theoretical support.
| [
{
"created": "Wed, 28 Sep 2005 14:00:19 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Soffer",
"Jacques",
""
]
] | We propose a novel mechanism for exclusive diffractive Higgs production $pp \to Hpp$, in which the Higgs carries a significant fraction of the projectile proton's momentum. This mechanism will then provide a clear experimental signal for Higgs production, due to the small background in this kinematic region. The key assumption underlying our analysis is the presence of intrinsic charm (IC) and intrinsic bottom (IB) fluctuations in the proton bound state, whose existence, at high light-cone momentum fraction $x$, has a substantial and growing experimental and theoretical support. |
2205.07896 | Eike M\"uller | Ricardo Z. Ferreira, M.C. David Marsh, Eike M\"uller | Strong supernovae bounds on ALPs from quantum loops | 36 pages, 10 figures. Changes in v2: gravitational redshift taken
into account, small corrections. This is an author-created, un-copyedited
version of an article published in JCAP. IOP Publishing Ltd is not
responsible for any errors or omissions in this version of the manuscript or
any version derived from it | JCAP11(2022)057 | 10.1088/1475-7516/2022/11/057 | null | hep-ph astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | We show that in theories of axionlike particles (ALPs) coupled to electrons
at tree-level, the one-loop effective coupling to photons is process dependent:
the effective coupling relevant for decay processes,
$g_{a\gamma}^{\text{(D)}}$, differs significantly from the coupling appearing
in the phenomenologically important Primakoff process,
$g_{a\gamma}^{\text{(P)}}$. We show that this has important implications for
the physics of massive ALPs in hot and dense environments, such as supernovae.
We derive, as a consequence, new limits on the ALP-electron coupling,
$\hat{g}_{ae}$, from SN 1987A by accounting for all relevant production
processes, including one-loop processes, and considering bounds from excess
cooling as well as the absence of an associated gamma-ray burst from ALP
decays. Our limits are among the strongest to date for ALP masses in the range
$0.03 \, \text{MeV} \, < m_a< 240 \, \text{MeV}$. Moreover, we also show how
cosmological bounds on the ALP-photon coupling translate into new, strong
limits on $\hat{g}_{ae}$ at one loop. Our analysis emphasises that large
hierarchies between ALP effective couplings are difficult to realise once
quantum loops are taken into account.
| [
{
"created": "Mon, 16 May 2022 18:00:01 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Nov 2022 09:52:18 GMT",
"version": "v2"
}
] | 2022-11-29 | [
[
"Ferreira",
"Ricardo Z.",
""
],
[
"Marsh",
"M. C. David",
""
],
[
"Müller",
"Eike",
""
]
] | We show that in theories of axionlike particles (ALPs) coupled to electrons at tree-level, the one-loop effective coupling to photons is process dependent: the effective coupling relevant for decay processes, $g_{a\gamma}^{\text{(D)}}$, differs significantly from the coupling appearing in the phenomenologically important Primakoff process, $g_{a\gamma}^{\text{(P)}}$. We show that this has important implications for the physics of massive ALPs in hot and dense environments, such as supernovae. We derive, as a consequence, new limits on the ALP-electron coupling, $\hat{g}_{ae}$, from SN 1987A by accounting for all relevant production processes, including one-loop processes, and considering bounds from excess cooling as well as the absence of an associated gamma-ray burst from ALP decays. Our limits are among the strongest to date for ALP masses in the range $0.03 \, \text{MeV} \, < m_a< 240 \, \text{MeV}$. Moreover, we also show how cosmological bounds on the ALP-photon coupling translate into new, strong limits on $\hat{g}_{ae}$ at one loop. Our analysis emphasises that large hierarchies between ALP effective couplings are difficult to realise once quantum loops are taken into account. |
hep-ph/0301099 | Johann Rafelski | J. Letessier (Paris 7) and J. Rafelski (Arizona) | QCD Equations of State and the QGP Liquid Model | 4 pages including 5 figures | Phys.Rev. C67 (2003) 031902 | 10.1103/PhysRevC.67.031902 | null | hep-ph nucl-th | null | Recent advances in the study of equations of state of thermal lattice Quantum
Chromodynamics obtained at non-zero baryon density allow validation of the
quark-gluon plasma (QGP) liquid model equations of state (EoS). We study here
the properties of the QGP-EoS near to the phase transformation boundary at
finite baryon density and show a close agreement with the lattice results.
| [
{
"created": "Wed, 15 Jan 2003 03:20:18 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Letessier",
"J.",
"",
"Paris 7"
],
[
"Rafelski",
"J.",
"",
"Arizona"
]
] | Recent advances in the study of equations of state of thermal lattice Quantum Chromodynamics obtained at non-zero baryon density allow validation of the quark-gluon plasma (QGP) liquid model equations of state (EoS). We study here the properties of the QGP-EoS near to the phase transformation boundary at finite baryon density and show a close agreement with the lattice results. |
hep-ph/9506257 | Helmut Neufeld | K. Huber and H. Neufeld | The decay $\rho^0 \to \pi^+ \pi^- \gamma$ and the chiral invariant
interactions of vector mesons | 7 pages, latex | Phys.Lett. B357 (1995) 221-224 | 10.1016/0370-2693(95)00869-M | UWThPh-1995-14 | hep-ph | null | Using the close relationship between the low--energy constants of chiral
perturbation theory and the chiral invariant interactions of the vector meson
resonances with the pseudoscalar mesons, we investigate the process $\rho^0 \ra
\pi^+ \pi^- \gamma$. Compared with the contribution from the pure
bremsstrahlung mechanism, we find an enhancement of the decay rate near the
endpoint of the photon energy spectrum. Such a particular shape of the
differential decay rate has indeed been observed experimentally and turns out
to be an important confirmation of the theoretical concept of chiral vector
meson dominance.
| [
{
"created": "Wed, 7 Jun 1995 15:02:44 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Huber",
"K.",
""
],
[
"Neufeld",
"H.",
""
]
] | Using the close relationship between the low--energy constants of chiral perturbation theory and the chiral invariant interactions of the vector meson resonances with the pseudoscalar mesons, we investigate the process $\rho^0 \ra \pi^+ \pi^- \gamma$. Compared with the contribution from the pure bremsstrahlung mechanism, we find an enhancement of the decay rate near the endpoint of the photon energy spectrum. Such a particular shape of the differential decay rate has indeed been observed experimentally and turns out to be an important confirmation of the theoretical concept of chiral vector meson dominance. |
1201.3756 | Eugenio Javier Garzon Alama | E. J. Garzon and E. Oset | Effects of pseudoscalar-baryon channels in the dynamically generated
vector-baryon resonances | null | null | 10.1140/epja/i2012-12005-x | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the interaction of vector mesons with the octet of stable baryons in
the framework of the local hidden gauge formalism using a coupled channels
unitary approach, including also the pseudoscalar-baryon channels which couple
to the same quantum numbers. We examine the scattering amplitudes and their
poles, which can be associated to known $J^P=1/2^-,3/2^-$ baryon resonances,
and determine the role of the pseudoscalar-baryon channels, changing the width
and eventually the mass of the resonances generated with only the basis of
vector-baryon states.
| [
{
"created": "Wed, 18 Jan 2012 11:17:28 GMT",
"version": "v1"
}
] | 2015-06-03 | [
[
"Garzon",
"E. J.",
""
],
[
"Oset",
"E.",
""
]
] | We study the interaction of vector mesons with the octet of stable baryons in the framework of the local hidden gauge formalism using a coupled channels unitary approach, including also the pseudoscalar-baryon channels which couple to the same quantum numbers. We examine the scattering amplitudes and their poles, which can be associated to known $J^P=1/2^-,3/2^-$ baryon resonances, and determine the role of the pseudoscalar-baryon channels, changing the width and eventually the mass of the resonances generated with only the basis of vector-baryon states. |
hep-ph/9905232 | Sinead Ryan | Sinead Ryan | Progress in leptonic and semileptonic decays in lattice QCD | 7 pages, talk given at DPF'99 Conference, Jan. 5-9 1999, Los Angeles,
CA | null | null | FERMILAB-CONF-99/054-T | hep-ph | null | The status of lattice calculations of heavy quark phenomenology is reviewed.
Particular emphasis is placed on the understanding and control of the
calculational uncertainties. The ensuing implications for constraining the CKM
matrix elements are discussed.
| [
{
"created": "Tue, 4 May 1999 09:17:37 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Ryan",
"Sinead",
""
]
] | The status of lattice calculations of heavy quark phenomenology is reviewed. Particular emphasis is placed on the understanding and control of the calculational uncertainties. The ensuing implications for constraining the CKM matrix elements are discussed. |
hep-ph/0211007 | Werner Vogelsang | B. Jager, A. Schafer, M. Stratmann, W. Vogelsang | Next-to-leading order QCD corrections to high-p_T pion production in
longitudinally polarized pp collisions | 23 pages, LaTeX, 6 figures as eps files | Phys.Rev.D67:054005,2003 | 10.1103/PhysRevD.67.054005 | BNL-NT-02/23, RBRC-293 | hep-ph | null | We present a calculation for single-inclusive large-p_T pion production in
longitudinally polarized pp collisions in next-to-leading order QCD. We choose
an approach where fully analytical expressions for the underlying partonic
hard-scattering cross sections are obtained. We simultaneously rederive the
corresponding corrections to unpolarized scattering and confirm the results
existing in the literature. Our results allow to calculate the double-spin
asymmetry A_LL^pi for this process at next-to-leading order, which will soon be
used at BNL-RHIC to measure the polarization of gluons in the nucleon.
| [
{
"created": "Fri, 1 Nov 2002 20:52:36 GMT",
"version": "v1"
}
] | 2010-04-06 | [
[
"Jager",
"B.",
""
],
[
"Schafer",
"A.",
""
],
[
"Stratmann",
"M.",
""
],
[
"Vogelsang",
"W.",
""
]
] | We present a calculation for single-inclusive large-p_T pion production in longitudinally polarized pp collisions in next-to-leading order QCD. We choose an approach where fully analytical expressions for the underlying partonic hard-scattering cross sections are obtained. We simultaneously rederive the corresponding corrections to unpolarized scattering and confirm the results existing in the literature. Our results allow to calculate the double-spin asymmetry A_LL^pi for this process at next-to-leading order, which will soon be used at BNL-RHIC to measure the polarization of gluons in the nucleon. |
1505.00011 | Eder Izaguirre | Eder Izaguirre, Gordan Krnjaic, Philip Schuster, Natalia Toro | Accelerating the Discovery of Light Dark Matter | 4 pages text + bibliography. 2 figures | Phys. Rev. Lett. 115, 251301 (2015) | 10.1103/PhysRevLett.115.251301 | null | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the present status of sub-GeV thermal dark matter annihilating
through Standard Model mixing and identify a small set of future experiments
that can decisively test these scenarios.
| [
{
"created": "Thu, 30 Apr 2015 20:00:30 GMT",
"version": "v1"
}
] | 2015-12-23 | [
[
"Izaguirre",
"Eder",
""
],
[
"Krnjaic",
"Gordan",
""
],
[
"Schuster",
"Philip",
""
],
[
"Toro",
"Natalia",
""
]
] | We analyze the present status of sub-GeV thermal dark matter annihilating through Standard Model mixing and identify a small set of future experiments that can decisively test these scenarios. |
2111.14298 | Weihua Yang | W. Yang | Handedness Correlation from Quark Polarization | null | null | 10.1016/j.nuclphysa.2022.122440 | null | hep-ph | http://creativecommons.org/licenses/by-nc-sa/4.0/ | Jet handedness as a measure of quark and/or gluon polarizations has been
proposed for nearly 30 years. It was demonstrated by measuring the correlation
of jet handedness in the electron positron annihilation process. Once
parameters are determined, the method could be used to measure quark and/or
gluon polarizations in other experiments. The reported data provided evidence
for the jet handedness and handedness correlation. However, the jet handedness
correlation measured in the electron positron annihilation process from the
opposite jets contradicts theoretical prediction by a sign. In order to explain
this, we present a chromo-hydrogen-like model in this paper. According to
calculations, both jet handedness and handedness correlation depend on not only
the polarization of the fragmenting valence quark but also the polarization of
the sea quark. It is the appearance of the sea quark polarization that can
solve the contradiction. In other words, measurements of jet handedness and
handedness correlation can be used to determine the sea quark polarization.
| [
{
"created": "Mon, 29 Nov 2021 02:09:43 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Mar 2022 07:58:10 GMT",
"version": "v2"
}
] | 2022-04-13 | [
[
"Yang",
"W.",
""
]
] | Jet handedness as a measure of quark and/or gluon polarizations has been proposed for nearly 30 years. It was demonstrated by measuring the correlation of jet handedness in the electron positron annihilation process. Once parameters are determined, the method could be used to measure quark and/or gluon polarizations in other experiments. The reported data provided evidence for the jet handedness and handedness correlation. However, the jet handedness correlation measured in the electron positron annihilation process from the opposite jets contradicts theoretical prediction by a sign. In order to explain this, we present a chromo-hydrogen-like model in this paper. According to calculations, both jet handedness and handedness correlation depend on not only the polarization of the fragmenting valence quark but also the polarization of the sea quark. It is the appearance of the sea quark polarization that can solve the contradiction. In other words, measurements of jet handedness and handedness correlation can be used to determine the sea quark polarization. |
1507.04350 | Dennis D. Dietrich | Dennis D. Dietrich | All-orders worldline holography and higher spins | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By using the worldline approach to quantum field theory, we demonstrate to
all orders that the sources of a quantum field theory over Mink$_4$ naturally
form a field theory over AdS$_5$. In particular, this holds for higher-spin
sources of a free scalar theory. We work entirely within quantum-field theory
and do not select a subset of diagrams. As auxiliary fifth dimension
Schwinger's proper time is grouped with the physical four spacetime dimensions
into an AdS$_5$ geometry. The four-dimensional sources are extended to
five-dimensional fields by a Wilson flow (gradient flow). A variational
principle for said flow reproduces the corresponding holographic computation.
| [
{
"created": "Wed, 15 Jul 2015 20:00:36 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Dec 2015 18:59:44 GMT",
"version": "v2"
}
] | 2015-12-07 | [
[
"Dietrich",
"Dennis D.",
""
]
] | By using the worldline approach to quantum field theory, we demonstrate to all orders that the sources of a quantum field theory over Mink$_4$ naturally form a field theory over AdS$_5$. In particular, this holds for higher-spin sources of a free scalar theory. We work entirely within quantum-field theory and do not select a subset of diagrams. As auxiliary fifth dimension Schwinger's proper time is grouped with the physical four spacetime dimensions into an AdS$_5$ geometry. The four-dimensional sources are extended to five-dimensional fields by a Wilson flow (gradient flow). A variational principle for said flow reproduces the corresponding holographic computation. |
0707.2222 | Jacques Soffer | Claude Bourrely, Jacques Soffer and Tai Tsun Wu | Impact picture for the analyzing power $A_N$ in very forward $pp$
elastic scattering | 6 pages, 6 figures, to appear Physical Review D | Phys.Rev.D76:053002,2007 | 10.1103/PhysRevD.76.053002 | null | hep-ph | null | In the framework of the impact picture we compute the analyzing power $A_N$
for $pp$ elastic scattering at high energy and in the very forward direction.
We consider the full set of Coulomb amplitudes and show that the interference
between the hadronic non-flip amplitude and the single-flip Coulomb amplitude
is sufficient to obtain a good agreement with the present experimental data.
This leads us to conclude that the single-flip hadronic amplitude is small in
this low momentum transfer region and it strongly suggests that this process
can be used as an absolute polarimeter at the BNL-RHIC $pp$ collider.
| [
{
"created": "Sun, 15 Jul 2007 16:53:18 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Bourrely",
"Claude",
""
],
[
"Soffer",
"Jacques",
""
],
[
"Wu",
"Tai Tsun",
""
]
] | In the framework of the impact picture we compute the analyzing power $A_N$ for $pp$ elastic scattering at high energy and in the very forward direction. We consider the full set of Coulomb amplitudes and show that the interference between the hadronic non-flip amplitude and the single-flip Coulomb amplitude is sufficient to obtain a good agreement with the present experimental data. This leads us to conclude that the single-flip hadronic amplitude is small in this low momentum transfer region and it strongly suggests that this process can be used as an absolute polarimeter at the BNL-RHIC $pp$ collider. |
2008.04023 | Arindam Das | Arindam Das, Nobuchika Okada | Associated Higgs boson production with $Z$ boson in the minimal $U(1)_X$
extended Standard Model | 19 Pages, 9 Figures | Nuclear Physics B 990(2023)116159 | 10.1016/j.nuclphysb.2023.116159 | OU-HET-1068 | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | The minimal $U(1)_X$ extension of the Standard Model (SM) is a simple and
well-motivated extension of the SM,
which supplements the SM with the seesaw mechanism for naturally generating
the light neutrino masses
and offers various interesting phenomenologies. In the model, the $U(1)_X$
charge of each SM field is characterized
by the $U(1)_X$ charge of the SM Higgs doublet with a free parameter $x_H$.
Due to the $U(1)_X$ charge of the Higgs doublet, the Higgs boson has a
trilinear coupling
with the $Z$ boson and the $U(1)_X$ gauge boson ($Z^\prime$). With this
coupling, a new process for the associated Higgs boson production
with a $Z$ boson arises through a $Z^\prime$ boson in the $s$-channel at high
energy colliders. In this paper, we calculate the associated Higgs boson
production at high energy colliders
and show interesting effects of the new $Z^\prime$ boson mediated process,
which can be tested in the future.
| [
{
"created": "Mon, 10 Aug 2020 11:08:36 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Mar 2023 02:27:04 GMT",
"version": "v2"
}
] | 2023-03-31 | [
[
"Das",
"Arindam",
""
],
[
"Okada",
"Nobuchika",
""
]
] | The minimal $U(1)_X$ extension of the Standard Model (SM) is a simple and well-motivated extension of the SM, which supplements the SM with the seesaw mechanism for naturally generating the light neutrino masses and offers various interesting phenomenologies. In the model, the $U(1)_X$ charge of each SM field is characterized by the $U(1)_X$ charge of the SM Higgs doublet with a free parameter $x_H$. Due to the $U(1)_X$ charge of the Higgs doublet, the Higgs boson has a trilinear coupling with the $Z$ boson and the $U(1)_X$ gauge boson ($Z^\prime$). With this coupling, a new process for the associated Higgs boson production with a $Z$ boson arises through a $Z^\prime$ boson in the $s$-channel at high energy colliders. In this paper, we calculate the associated Higgs boson production at high energy colliders and show interesting effects of the new $Z^\prime$ boson mediated process, which can be tested in the future. |
1806.10107 | A. N. Ivanov | A. N. Ivanov, R. H\"ollwieser, N. I. Troitskaya, M. Wellenzohn, Ya. A.
Berdnikov | Neutron Dark Matter Decays | 26 pages, 11 figures, a quark level formulation of our model is added | null | null | null | hep-ph gr-qc nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyse the discrepancy between the neutron lifetimes measured in the
bottle and beam experiments. Following Fornal and Grinstein (Phys. Rev. Lett.
120, 191801 (2018)) we propose an explanation of such a puzzle by the dark
matter channels of the neutron decay. However, unlike Fornal and Grinstein in
addition to the dark matter decay channel n -> \chi + e^- + e^+, where \chi is
a dark matter Dirac fermion and (e^-e^+) is an electron--positron pair, we
assume the existence of the dark matter channel n -> chi + \nu_e + \bar{\nu}_e,
where \nu_e \bar{\nu}_e is the electron neutrino-antineutrino pair. This allows
to describe the discrepancy between the measurements of the neutron lifetime
even in case of an unobservability of the dark matter decay channel n -> \chi +
e^- + e^+, which may be below the reaction threshold. The existence of the
coupling n -> \chi + e^- + e^+ can be observed experimentally by measuring
electron-neutron scattering e^- + n -> \chi + e^- at very low electron
energies, induced with the strength as of the decay n -> \chi + \nu_e +
\bar{\nu}_e$. We propose a gauge invariant quantum field theory model with
SU_L(2)\times U_R(1) \times U_R'(1)\times U''_L(1) symmetry for the UV
completion of the effective (n\chi \ell \bar{\ell}) interaction, where
\ell(\bar{\ell}) is electron (positron) or neutrino(antineutrino).
| [
{
"created": "Tue, 26 Jun 2018 16:58:36 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Aug 2018 07:44:55 GMT",
"version": "v2"
},
{
"created": "Sat, 15 Sep 2018 11:19:36 GMT",
"version": "v3"
},
{
"created": "Sun, 30 Sep 2018 15:55:55 GMT",
"version": "v4"
}
] | 2018-10-02 | [
[
"Ivanov",
"A. N.",
""
],
[
"Höllwieser",
"R.",
""
],
[
"Troitskaya",
"N. I.",
""
],
[
"Wellenzohn",
"M.",
""
],
[
"Berdnikov",
"Ya. A.",
""
]
] | We analyse the discrepancy between the neutron lifetimes measured in the bottle and beam experiments. Following Fornal and Grinstein (Phys. Rev. Lett. 120, 191801 (2018)) we propose an explanation of such a puzzle by the dark matter channels of the neutron decay. However, unlike Fornal and Grinstein in addition to the dark matter decay channel n -> \chi + e^- + e^+, where \chi is a dark matter Dirac fermion and (e^-e^+) is an electron--positron pair, we assume the existence of the dark matter channel n -> chi + \nu_e + \bar{\nu}_e, where \nu_e \bar{\nu}_e is the electron neutrino-antineutrino pair. This allows to describe the discrepancy between the measurements of the neutron lifetime even in case of an unobservability of the dark matter decay channel n -> \chi + e^- + e^+, which may be below the reaction threshold. The existence of the coupling n -> \chi + e^- + e^+ can be observed experimentally by measuring electron-neutron scattering e^- + n -> \chi + e^- at very low electron energies, induced with the strength as of the decay n -> \chi + \nu_e + \bar{\nu}_e$. We propose a gauge invariant quantum field theory model with SU_L(2)\times U_R(1) \times U_R'(1)\times U''_L(1) symmetry for the UV completion of the effective (n\chi \ell \bar{\ell}) interaction, where \ell(\bar{\ell}) is electron (positron) or neutrino(antineutrino). |
1303.5447 | Giulia Zanderighi | John M. Campbell, R. Keith Ellis, Paolo Nason and Giulia Zanderighi | W and Z bosons in association with two jets using the POWHEG method | 35 pages, 43 figures | null | 10.1007/JHEP08(2013)005 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we present the implementation of generators for W and Z bosons
in association with two jets interfaced to parton showers using the POWHEG BOX.
We incorporate matrix elements from the parton-level Monte Carlo program MCFM
in the POWHEG BOX, allowing for a considerable improvement in speed compared to
previous implementations. We address certain problems that arise when processes
that are singular at the Born level are implemented in a shower framework using
either a generation cut or a Born suppression factor to yield weighted events.
In such a case, events with very large weights can be generated after the
shower through a number of mechanisms. Events with very small transverse
momentum at the Born level can develop large transverse momentum either after
the hardest emission, after the shower, or after the inclusion of multi-parton
interactions. We present a solution to this problem that can be easily
implemented in the POWHEG BOX. We also show that a full solution to this
problem can only be achieved if the generator maintains physical validity also
when the transverse momentum of the emitted partons becomes unresolved. One
such scheme is the recently-proposed MiNLO method for the choice of scale and
the exponentiation of Sudakov form factors in NLO computations. We present a
validation study of our generators, by comparing their output to available LHC
data.
| [
{
"created": "Thu, 21 Mar 2013 20:00:05 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Mar 2013 15:27:18 GMT",
"version": "v2"
}
] | 2015-06-15 | [
[
"Campbell",
"John M.",
""
],
[
"Ellis",
"R. Keith",
""
],
[
"Nason",
"Paolo",
""
],
[
"Zanderighi",
"Giulia",
""
]
] | In this work we present the implementation of generators for W and Z bosons in association with two jets interfaced to parton showers using the POWHEG BOX. We incorporate matrix elements from the parton-level Monte Carlo program MCFM in the POWHEG BOX, allowing for a considerable improvement in speed compared to previous implementations. We address certain problems that arise when processes that are singular at the Born level are implemented in a shower framework using either a generation cut or a Born suppression factor to yield weighted events. In such a case, events with very large weights can be generated after the shower through a number of mechanisms. Events with very small transverse momentum at the Born level can develop large transverse momentum either after the hardest emission, after the shower, or after the inclusion of multi-parton interactions. We present a solution to this problem that can be easily implemented in the POWHEG BOX. We also show that a full solution to this problem can only be achieved if the generator maintains physical validity also when the transverse momentum of the emitted partons becomes unresolved. One such scheme is the recently-proposed MiNLO method for the choice of scale and the exponentiation of Sudakov form factors in NLO computations. We present a validation study of our generators, by comparing their output to available LHC data. |
2306.10199 | Chien Yeah Seng | Chien-Yeah Seng, Vincenzo Cirigliano, Xu Feng, Mikhail Gorchtein,
Luchang Jin and Gerald A. Miller | Quark mass difference effects in hadronic Fermi matrix elements from
first principles | Version accepted by PLB | Phys.Lett.B 846 (2023) 138259 | 10.1016/j.physletb.2023.138259 | null | hep-ph hep-ex hep-lat nucl-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | It was recently estimated that the strong isospin-symmetry breaking (ISB)
corrections to the Fermi matrix element in free neutron decay could be of the
order $10^{-4}$, one order of magnitude larger than the na\"{\i}ve estimate
based on the Behrends-Sirlin-Ademollo-Gatto theorem. To investigate this claim,
we derive a general expression of the leading ISB correction to hadronic Fermi
matrix elements, which takes the form of a four-point correlation function in
lattice gauge theory and is straightforward to compute from first principles.
Our formalism paves the way for the first determination of such correction in
the neutron sector with fully-controlled theory uncertainties.
| [
{
"created": "Fri, 16 Jun 2023 22:32:44 GMT",
"version": "v1"
},
{
"created": "Tue, 31 Oct 2023 06:53:41 GMT",
"version": "v2"
}
] | 2023-11-01 | [
[
"Seng",
"Chien-Yeah",
""
],
[
"Cirigliano",
"Vincenzo",
""
],
[
"Feng",
"Xu",
""
],
[
"Gorchtein",
"Mikhail",
""
],
[
"Jin",
"Luchang",
""
],
[
"Miller",
"Gerald A.",
""
]
] | It was recently estimated that the strong isospin-symmetry breaking (ISB) corrections to the Fermi matrix element in free neutron decay could be of the order $10^{-4}$, one order of magnitude larger than the na\"{\i}ve estimate based on the Behrends-Sirlin-Ademollo-Gatto theorem. To investigate this claim, we derive a general expression of the leading ISB correction to hadronic Fermi matrix elements, which takes the form of a four-point correlation function in lattice gauge theory and is straightforward to compute from first principles. Our formalism paves the way for the first determination of such correction in the neutron sector with fully-controlled theory uncertainties. |
hep-ph/9909457 | Alec T. Habig | E.M. Lipmanov | Neutrino Flavor Tagging in a Four-Neutrino Mixing and Oscillation Model | 3 pages; A remark added on the meaning of the auxiliary neutrino
fields in the limit of mass-degenerate neutrino doublets | null | null | null | hep-ph | null | A neutrino mass dominance quantity is introduced for tagging the neutrino
flavor in the phenomenological two-parameter four neutrino mixing matrix with
two neutrino mass doublets and thorough maximal neutrino doublet mixing. While
there is no hierarchy of the neutrino masses in the neutrino flavor eigenstates
of this model, it may rather be a special hierarchy of the mass dominance
ratios in these eigenstates. A neutrino flavor hierarchy condition is
suggested: a direct link between the neutrino flavor and the flavor of the
charged leptons which interconnects the two mixing angles, theta and phi, via
the charged lepton mass ratios, with the net result tg^2 phi = (tg^2
theta)^gamma, gamma ~ 2.06. It leads to distinct inferences testable at SNO and
Super-K.
| [
{
"created": "Tue, 21 Sep 1999 18:27:48 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Oct 1999 18:40:17 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Lipmanov",
"E. M.",
""
]
] | A neutrino mass dominance quantity is introduced for tagging the neutrino flavor in the phenomenological two-parameter four neutrino mixing matrix with two neutrino mass doublets and thorough maximal neutrino doublet mixing. While there is no hierarchy of the neutrino masses in the neutrino flavor eigenstates of this model, it may rather be a special hierarchy of the mass dominance ratios in these eigenstates. A neutrino flavor hierarchy condition is suggested: a direct link between the neutrino flavor and the flavor of the charged leptons which interconnects the two mixing angles, theta and phi, via the charged lepton mass ratios, with the net result tg^2 phi = (tg^2 theta)^gamma, gamma ~ 2.06. It leads to distinct inferences testable at SNO and Super-K. |
hep-ph/9604341 | Stuart Samuel | Stuart Samuel (City College of New York) | Bimodal Coherence in Dense Self-Interacting Neutrino Gases | 21 pages in Latex, 11 figures packaged in one Postscript file.
Figures also obtainable as 20 gif files at
http://www.sci.ccny.cuny.edu/~ssamuel/bimodalfigs.html Revision on 4/19/96
was to pack the figures more sensibly. This paper is to appear in a May issue
of Phys. Rev. D | Phys.Rev.D53:5382-5393,1996 | 10.1103/PhysRevD.53.5382 | MPI-PhT/95-57, CCNY-HEP-95/5 (July, 1995) | hep-ph astro-ph hep-th | null | Analytical solutions are obtained to the nonlinear equations describing
neutrino oscillations when explicit neutrino-antineutrino asymmetries are
present. Such a system occurs in the early Universe if neutrinos have a
non-zero chemical potential. Solutions to the equations lead to a new type of
coherent behavior governed by two modes. These bimodal solutions provide new
insights into dense neutrino gases and into neutrino oscillations in the early
Universe, thereby allowing one to surmise the flavor behavior of neutrinos with
a non-zero chemical potential.
| [
{
"created": "Tue, 16 Apr 1996 20:24:39 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Apr 1996 15:15:51 GMT",
"version": "v2"
}
] | 2011-07-18 | [
[
"Samuel",
"Stuart",
"",
"City College of New York"
]
] | Analytical solutions are obtained to the nonlinear equations describing neutrino oscillations when explicit neutrino-antineutrino asymmetries are present. Such a system occurs in the early Universe if neutrinos have a non-zero chemical potential. Solutions to the equations lead to a new type of coherent behavior governed by two modes. These bimodal solutions provide new insights into dense neutrino gases and into neutrino oscillations in the early Universe, thereby allowing one to surmise the flavor behavior of neutrinos with a non-zero chemical potential. |
2001.00161 | Muyang Chen | Muyang Chen and Lei Chang and Yu-xin Liu | $B_c$ Meson Spectrum Via Dyson-Schwinger Equation and Bethe-Salpeter
Equation Approach | null | Phys. Rev. D 101, 056002 (2020) | 10.1103/PhysRevD.101.056002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We predict the masses of the lowlying $B_c$ mesons with $J^P =
0^-,\,1^-,\,0^+,\,1^+,\,2^+$, using a flavor dependent interaction pattern
which gives an unified successful description of the light, heavy-light and
heavy mesons and is also appliable to the radial excited heavy mesons. The
errors are controlled carefully. With the errors from the RL approximation
subduced, our predictions are consistent with the lQCD and quark model results,
which supports strongly that the flavor dependent interaction pattern is
reasonable. Our predictions provide significant guides to the experiment search
of the $B_c$ mesons.
| [
{
"created": "Wed, 1 Jan 2020 08:20:09 GMT",
"version": "v1"
}
] | 2020-03-11 | [
[
"Chen",
"Muyang",
""
],
[
"Chang",
"Lei",
""
],
[
"Liu",
"Yu-xin",
""
]
] | We predict the masses of the lowlying $B_c$ mesons with $J^P = 0^-,\,1^-,\,0^+,\,1^+,\,2^+$, using a flavor dependent interaction pattern which gives an unified successful description of the light, heavy-light and heavy mesons and is also appliable to the radial excited heavy mesons. The errors are controlled carefully. With the errors from the RL approximation subduced, our predictions are consistent with the lQCD and quark model results, which supports strongly that the flavor dependent interaction pattern is reasonable. Our predictions provide significant guides to the experiment search of the $B_c$ mesons. |
hep-ph/0102327 | Leszek Roszkowski | Leszek Roszkowski | Non-Baryonic Dark Matter | Invited plenary review talk given at 6th International Workshop on
Topics in Astroparticle and Underground Physics (TAUP 99), 6-10 September,
1999, Paris, France | null | null | CERN--TH/2001-061 | hep-ph astro-ph | null | There exist several well-motivated candidates for non-baryonic cold dark
matter, including neutralinos, axions, axinos, gravitinos, Wimpzillas. I review
the dark matter properties of the neutralino and the current status of its
detection. I also discuss the axino as a new interesting alternative.
| [
{
"created": "Tue, 27 Feb 2001 14:53:12 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Roszkowski",
"Leszek",
""
]
] | There exist several well-motivated candidates for non-baryonic cold dark matter, including neutralinos, axions, axinos, gravitinos, Wimpzillas. I review the dark matter properties of the neutralino and the current status of its detection. I also discuss the axino as a new interesting alternative. |
2110.07890 | Pablo Escribano | Pablo Escribano | A generalization of the Scotogenic model | 5 pages, 2 figures. Based on the work arXiv:2004.05172. Contribution
to the TAUP 2021 conference proceedings | null | 10.1088/1742-6596/2156/1/012099 | IFIC/21-37 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The Scotogenic model is a radiative neutrino mass model able to induce
Majorana neutrino masses at the 1-loop level and simultaneously include a dark
matter candidate. In this work, we generalize the original Scotogenic model to
arbitrary numbers of generations of the Scotogenic states. After that, we
present the light neutrino mass matrix, with some details of its derivation,
and provide a useful approximate expression as well. Finally, we numerically
solve the Renormalization Group Equations to explore the high-energy behavior
of the model.
| [
{
"created": "Fri, 15 Oct 2021 07:21:50 GMT",
"version": "v1"
}
] | 2022-03-02 | [
[
"Escribano",
"Pablo",
""
]
] | The Scotogenic model is a radiative neutrino mass model able to induce Majorana neutrino masses at the 1-loop level and simultaneously include a dark matter candidate. In this work, we generalize the original Scotogenic model to arbitrary numbers of generations of the Scotogenic states. After that, we present the light neutrino mass matrix, with some details of its derivation, and provide a useful approximate expression as well. Finally, we numerically solve the Renormalization Group Equations to explore the high-energy behavior of the model. |
2207.10715 | Lukas Allwicher | Lukas Allwicher, and Nud\v{z}eim Selimovi\'c | Lepton Flavour Universality in $\tau$ decays | Contribution to the 56th Rencontres de Moriond and to La Thuile 2022
- Les Rencontres de Physique de la Vall\'ee d'Aoste | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The evidence for Lepton Flavour Universality (LFU) violation in semileptonic
$B$-decays has been rising over the past few years. Relying on generic
effective field theory (EFT) results, it has been shown that models addressing
the $B$-anomalies necessarily lead, at one-loop, to deviations from LFU in
$\tau$ decays at the few per-mil level. Once a (renormalizable) UV model is
specified, the leading-log EFT result receives finite corrections from the
matching at the UV scale. We discuss such corrections in a motivated class of
models for the B-anomalies, based on an extended $SU(4) \times SU(3) \times
SU(2) \times U(1)$ gauge sector. In this scenario, we obtain precise
predictions for the effective $W$-boson and $Z$-boson couplings to leptons in
terms of the masses and couplings of the new heavy fields. We confirm a few
per-mil deviation from universality, within reach of future high-precision
experiments.
| [
{
"created": "Thu, 21 Jul 2022 19:07:49 GMT",
"version": "v1"
}
] | 2022-07-25 | [
[
"Allwicher",
"Lukas",
""
],
[
"Selimović",
"Nudžeim",
""
]
] | The evidence for Lepton Flavour Universality (LFU) violation in semileptonic $B$-decays has been rising over the past few years. Relying on generic effective field theory (EFT) results, it has been shown that models addressing the $B$-anomalies necessarily lead, at one-loop, to deviations from LFU in $\tau$ decays at the few per-mil level. Once a (renormalizable) UV model is specified, the leading-log EFT result receives finite corrections from the matching at the UV scale. We discuss such corrections in a motivated class of models for the B-anomalies, based on an extended $SU(4) \times SU(3) \times SU(2) \times U(1)$ gauge sector. In this scenario, we obtain precise predictions for the effective $W$-boson and $Z$-boson couplings to leptons in terms of the masses and couplings of the new heavy fields. We confirm a few per-mil deviation from universality, within reach of future high-precision experiments. |
hep-ph/9510264 | null | Matthias Burkardt | Confinement and the Transverse Lattice | 5 pages, LATEX, 1 postscript figure | null | null | null | hep-ph hep-lat hep-th nucl-th | null | The status of the transverse lattice formulation of light-front QCD is
reviewed. It is explained how confinement arises in this formulation for large
lattice spacing. The nonperturbative renormalization procedure is outlined in
general and a more detailed discussion is given for the case of
$QCD_{2+1}(N_C\rightarrow \infty)$.
| [
{
"created": "Wed, 11 Oct 1995 00:12:44 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Burkardt",
"Matthias",
""
]
] | The status of the transverse lattice formulation of light-front QCD is reviewed. It is explained how confinement arises in this formulation for large lattice spacing. The nonperturbative renormalization procedure is outlined in general and a more detailed discussion is given for the case of $QCD_{2+1}(N_C\rightarrow \infty)$. |
hep-ph/9307365 | Harada Masayasu | Masako Bando and Masayasu Harada | Interpolating Axial Anomaly Induced Amplitudes | LaTeX, 25 pages + 7 figures, (figures are included as uuencoded
files), KUNS-1209 HE(TH) 93/06 | Prog.Theor.Phys. 92 (1994) 583-602 | 10.1143/PTP.92.583 | null | hep-ph | null | We propose an interpolating formula for the amplitude induced by the axial
anomaly, concentrating on the $\pi^0\gamma^{\ast}\gamma^{\ast}$ transition form
factor. The QCD corrections to this amplitude are generally described by two
major contributions coming from the $q\bar{q}$ bound state and the background
continuous spectrum, respectively.
For the first contribution, we include the lowest vector bound state using
the realization of the dynamical gauge boson of hidden local symmetry. The
second contribution is included as the triangle quark loop in which a
constituent mass is adopted as a internal quark mass and the amplitudes are
smeared out around the threshold. Using the resulting form factor, we fit the
experimental data for the $\pi^0\gamma$ and the $\omega\pi^0$ transition form
factors and show that our result describes the experimental data well.
| [
{
"created": "Thu, 29 Jul 1993 16:47:51 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Bando",
"Masako",
""
],
[
"Harada",
"Masayasu",
""
]
] | We propose an interpolating formula for the amplitude induced by the axial anomaly, concentrating on the $\pi^0\gamma^{\ast}\gamma^{\ast}$ transition form factor. The QCD corrections to this amplitude are generally described by two major contributions coming from the $q\bar{q}$ bound state and the background continuous spectrum, respectively. For the first contribution, we include the lowest vector bound state using the realization of the dynamical gauge boson of hidden local symmetry. The second contribution is included as the triangle quark loop in which a constituent mass is adopted as a internal quark mass and the amplitudes are smeared out around the threshold. Using the resulting form factor, we fit the experimental data for the $\pi^0\gamma$ and the $\omega\pi^0$ transition form factors and show that our result describes the experimental data well. |
0809.1707 | Seong Youl Choi | S.Y. Choi | Complementarity of the CERN Large Hadron Collider and the $e^+e^-$
International Linear Collider | 14 pages, 17 figures, to be published in "Supersymmetry on the Eve of
the LHC", a special volume of European Physical Journal C, Particles and
Fields (EPJC) in memory of Julius Wess | Eur.Phys.J.C59:543-556,2009 | 10.1140/epjc/s10052-008-0755-7 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The next-generation high-energy facilities, the CERN Large Hadron Collider
(LHC) and the prospective $e^+e^-$ International Linear Collider (ILC), are
expected to unravel new structures of matter and forces from the electroweak
scale to the TeV scale. In this report we review the complementary role of LHC
and ILC in drawing a comprehensive and high-precision picture of the mechanism
breaking the electroweak symmetries and generating mass, and the unification of
forces in the frame of supersymmetry.
| [
{
"created": "Wed, 10 Sep 2008 04:09:30 GMT",
"version": "v1"
}
] | 2009-02-18 | [
[
"Choi",
"S. Y.",
""
]
] | The next-generation high-energy facilities, the CERN Large Hadron Collider (LHC) and the prospective $e^+e^-$ International Linear Collider (ILC), are expected to unravel new structures of matter and forces from the electroweak scale to the TeV scale. In this report we review the complementary role of LHC and ILC in drawing a comprehensive and high-precision picture of the mechanism breaking the electroweak symmetries and generating mass, and the unification of forces in the frame of supersymmetry. |
hep-ph/0204359 | Maxim Pospelov | Oleg Lebedev and Maxim Pospelov | Electric Dipole Moments in The Limit of Heavy Superpartners | minor revisions, to appear in Phys. Rev. Lett | Phys.Rev.Lett. 89 (2002) 101801 | 10.1103/PhysRevLett.89.101801 | susx-th/02-010 | hep-ph | null | Supersymmetric loop corrections induce potentially large CP-violating
couplings of the Higgs bosons to nucleons and electrons that do not vanish in
the limit of heavy superpartners. The Higgs-mediated CP-odd four-fermion
operators are enhanced by tan^3 beta and induce electric dipole moments of
heavy atoms which exceed the current experimental bounds for the electroweak
scale Higgs masses and tan beta > 10. If only the first two sfermion
generations are heavy, the Higgs-mediated contributions typically dominate over
the Barr-Zee type two-loop diagrams at tan beta > 30.
| [
{
"created": "Tue, 30 Apr 2002 16:51:04 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Jul 2002 12:19:33 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Lebedev",
"Oleg",
""
],
[
"Pospelov",
"Maxim",
""
]
] | Supersymmetric loop corrections induce potentially large CP-violating couplings of the Higgs bosons to nucleons and electrons that do not vanish in the limit of heavy superpartners. The Higgs-mediated CP-odd four-fermion operators are enhanced by tan^3 beta and induce electric dipole moments of heavy atoms which exceed the current experimental bounds for the electroweak scale Higgs masses and tan beta > 10. If only the first two sfermion generations are heavy, the Higgs-mediated contributions typically dominate over the Barr-Zee type two-loop diagrams at tan beta > 30. |
hep-ph/9704271 | Tpc | Zong-Guo Si, Qu-Bing Xie, Qun Wang | Study of Baryon Antibaryon Rapidity Correlation in e^+e^- Annihilation
by Quark Combination Model | 18 Pages, RevTex(to appear in Commun. Theor. Phys.) | null | 10.1088/0253-6102/28/1/85 | null | hep-ph | null | We use Quark Combination Model to study baryon antibaryon rapidity
correlation in e^+e^- annihilation and compare our predictions with the
available data. We find that these results and relevant properties are all
consistent with data. So the evidence to rule out Quark Combination Model which
has long been cited in literatures does not exist.
| [
{
"created": "Wed, 9 Apr 1997 11:16:17 GMT",
"version": "v1"
}
] | 2018-01-17 | [
[
"Si",
"Zong-Guo",
""
],
[
"Xie",
"Qu-Bing",
""
],
[
"Wang",
"Qun",
""
]
] | We use Quark Combination Model to study baryon antibaryon rapidity correlation in e^+e^- annihilation and compare our predictions with the available data. We find that these results and relevant properties are all consistent with data. So the evidence to rule out Quark Combination Model which has long been cited in literatures does not exist. |
hep-ph/0605159 | Stephen West | Stephen M. West | Asymmetric Sneutrino Dark Matter | 4 pages, 4 figures. Talk given at the XLIst Rencontres de Moriond,
Electroweak Interactions And Unified Theories, March 11 - 18, 2006 | null | null | OUTP-0613P | hep-ph | null | It is known that the cosmological baryon density (Omega(b)) and dark matter
density (Omega(dm)) have strikingly similar values. However, in most theories
of the early Universe, each density is explained by separate dynamics and
consequently there is no compelling reason for this observation. In this note,
I briefly review a model in which the dark matter possesses a
particle-antiparticle asymmetry. This asymmetry determines both the baryon
asymmetry and strongly affects the dark matter density, thus naturally linking
Omega(b) and Omega(dm). In these models it is shown that sneutrinos can play
the role of such dark matter.
| [
{
"created": "Sat, 13 May 2006 20:54:44 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"West",
"Stephen M.",
""
]
] | It is known that the cosmological baryon density (Omega(b)) and dark matter density (Omega(dm)) have strikingly similar values. However, in most theories of the early Universe, each density is explained by separate dynamics and consequently there is no compelling reason for this observation. In this note, I briefly review a model in which the dark matter possesses a particle-antiparticle asymmetry. This asymmetry determines both the baryon asymmetry and strongly affects the dark matter density, thus naturally linking Omega(b) and Omega(dm). In these models it is shown that sneutrinos can play the role of such dark matter. |
2009.05848 | Serdar Spor | S. Spor, M. K\"oksal | Search for the anomalous $WW\gamma$ couplings through the process
$e^-e^+\,\rightarrow\,\nu_e\bar{\nu}_e\gamma$ at ILC with unpolarized and
polarize beams | 28 pages, 9 figures, 7 tables | Physics Letters B, 820 (2021) 136533 | 10.1016/j.physletb.2021.136533 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the anomalous $W^+W^-\gamma$ couplings through the process
$e^-e^+\,\rightarrow\,\nu_e\bar{\nu}_e\gamma$ for unpolarized and polarized
electron (positron) beams at the International Linear Collider. We give the
95$\%$ Confidence Level limits on the anomalous couplings with and without the
systematic uncertainties for various values of center-of-mass energies and the
integrated luminosities. We show that the obtained limits on the anomalous
couplings through the process $e^-e^+\,\rightarrow\,\nu_e\bar{\nu}_e\gamma$ can
highly improve the current experimental limits.
| [
{
"created": "Sat, 12 Sep 2020 18:59:23 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Jul 2021 20:57:04 GMT",
"version": "v2"
}
] | 2021-08-03 | [
[
"Spor",
"S.",
""
],
[
"Köksal",
"M.",
""
]
] | We investigate the anomalous $W^+W^-\gamma$ couplings through the process $e^-e^+\,\rightarrow\,\nu_e\bar{\nu}_e\gamma$ for unpolarized and polarized electron (positron) beams at the International Linear Collider. We give the 95$\%$ Confidence Level limits on the anomalous couplings with and without the systematic uncertainties for various values of center-of-mass energies and the integrated luminosities. We show that the obtained limits on the anomalous couplings through the process $e^-e^+\,\rightarrow\,\nu_e\bar{\nu}_e\gamma$ can highly improve the current experimental limits. |
hep-ph/0610414 | Pran Nath | Pran Nath | Dark Matter in SUGRA, Strings and Branes | Invited talk at the International Conference "Idenfication of Dark
Matter-2006", September 11-16, 2006, Rhodes, Greece. 11 pages, 3 figures | null | 10.1142/9789812770288_0003 | null | hep-ph hep-th | null | A brief review is given of dark matter in SUGRA, strings and branes. For
SUGRA models the implications of Yukawa coupling unification on dark matter are
discussed in the light of $g-2$ and $b\to s\gamma$ constraints. A brief
discussion is given of the dark matter in orbifold string compactifications
under constraints of modular invariance and radiative breaking of the
electroweak symmetry. Finally a new candidate for dark matter - an extra-weakly
interacting massive particle or an XWIMP- is discussed. Such dark matter can
arise in a wide class of models, including the Stueckelberg extensions of MSSM,
in U(1) extensions of MSSM with off diagonal kinetic energy, and possibly in a
wider class of models which may have a string/D-brane origin. Satisfaction of
the relic density of XWIMPs consistent with WMAP is also discussed.
| [
{
"created": "Mon, 30 Oct 2006 18:39:38 GMT",
"version": "v1"
},
{
"created": "Sun, 5 Nov 2006 16:24:33 GMT",
"version": "v2"
}
] | 2016-11-09 | [
[
"Nath",
"Pran",
""
]
] | A brief review is given of dark matter in SUGRA, strings and branes. For SUGRA models the implications of Yukawa coupling unification on dark matter are discussed in the light of $g-2$ and $b\to s\gamma$ constraints. A brief discussion is given of the dark matter in orbifold string compactifications under constraints of modular invariance and radiative breaking of the electroweak symmetry. Finally a new candidate for dark matter - an extra-weakly interacting massive particle or an XWIMP- is discussed. Such dark matter can arise in a wide class of models, including the Stueckelberg extensions of MSSM, in U(1) extensions of MSSM with off diagonal kinetic energy, and possibly in a wider class of models which may have a string/D-brane origin. Satisfaction of the relic density of XWIMPs consistent with WMAP is also discussed. |
1808.03695 | Paolo Parotto | Paolo Parotto | Equation of state for QCD with a critical point from the 3D Ising Model | 3 pages, 1 figure, Quark Matter 2018 conference proceeding | null | 10.1016/j.nuclphysa.2018.09.077 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Current knowledge of the finite-density QCD equation of state from first
principles is limited to a Taylor expansion in the baryonic chemical potential
around $\mu_B=0$. By means of a scaling form for the equation of state of the
3D Ising model and a non-universal, parametrized map to QCD coordinates, we
construct a family of equations of state matching state of the art first
principle Lattice QCD calculations and including the correct critical behavior,
which can be readily employed in hydrodynamical simulations of heavy ion
collisions at finite density, covering most of the BES range at RHIC. This
contribution reports on work done within the Fluctuations/Equation of State
working group of the BEST Collaboration.
| [
{
"created": "Fri, 10 Aug 2018 20:33:34 GMT",
"version": "v1"
}
] | 2019-02-20 | [
[
"Parotto",
"Paolo",
""
]
] | Current knowledge of the finite-density QCD equation of state from first principles is limited to a Taylor expansion in the baryonic chemical potential around $\mu_B=0$. By means of a scaling form for the equation of state of the 3D Ising model and a non-universal, parametrized map to QCD coordinates, we construct a family of equations of state matching state of the art first principle Lattice QCD calculations and including the correct critical behavior, which can be readily employed in hydrodynamical simulations of heavy ion collisions at finite density, covering most of the BES range at RHIC. This contribution reports on work done within the Fluctuations/Equation of State working group of the BEST Collaboration. |
hep-ph/9804229 | Indranil Dasgupta | Indranil DasGupta, Ricardo Rademacher and Peter Suranyi | Improved Mass Constraints in the MSSM from Vacuum Stability | LaTex. 15 pages. 4 postscript figures (uses epsf). Some minor
corrections. Enlarged data set. Figures showing data have been improved | Phys.Lett. B447 (1999) 284-291 | 10.1016/S0370-2693(98)01582-2 | UCTP105.98 | hep-ph | null | Using a simple numerical method, we compute the stability of the MSSM vacuum
with respect to tunneling. The stability criterion is then used to put
restrictions on the mass parameters. These restrictions are necessary
conditions for the vacuum stability and compliment the existing sufficiency
conditions obtained analytically.
| [
{
"created": "Sat, 4 Apr 1998 01:05:41 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Apr 1998 00:03:27 GMT",
"version": "v2"
},
{
"created": "Tue, 13 Oct 1998 17:53:20 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"DasGupta",
"Indranil",
""
],
[
"Rademacher",
"Ricardo",
""
],
[
"Suranyi",
"Peter",
""
]
] | Using a simple numerical method, we compute the stability of the MSSM vacuum with respect to tunneling. The stability criterion is then used to put restrictions on the mass parameters. These restrictions are necessary conditions for the vacuum stability and compliment the existing sufficiency conditions obtained analytically. |
2403.00559 | Zhi-zhong Xing | Zhi-zhong Xing | A new Wolfenstein-like expansion of lepton flavor mixing towards
understanding its fine structure | 14 pages, 1 figure. More discussions and references added. Accepted
for publication in Phys. Lett. B | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | Taking the tri-bimaximal flavor mixing pattern as a particular basis, we
propose a new way to expand the $3\times 3$ unitary
Pontecorvo-Maki-Nakagawa-Sakata (PMNS) lepton flavor mixing matrix $U$ in
powers of the magnitude of its smallest element $\xi \equiv \left|U^{}_{e
3}\right| \simeq 0.149$. Such a Wolfenstein-like parametrization of $U$ allows
us to easily describe the salient features and fine structures of flavor mixing
and CP violation, both in vacuum and in matter.
| [
{
"created": "Fri, 1 Mar 2024 14:36:01 GMT",
"version": "v1"
},
{
"created": "Sun, 28 Apr 2024 01:08:09 GMT",
"version": "v2"
}
] | 2024-04-30 | [
[
"Xing",
"Zhi-zhong",
""
]
] | Taking the tri-bimaximal flavor mixing pattern as a particular basis, we propose a new way to expand the $3\times 3$ unitary Pontecorvo-Maki-Nakagawa-Sakata (PMNS) lepton flavor mixing matrix $U$ in powers of the magnitude of its smallest element $\xi \equiv \left|U^{}_{e 3}\right| \simeq 0.149$. Such a Wolfenstein-like parametrization of $U$ allows us to easily describe the salient features and fine structures of flavor mixing and CP violation, both in vacuum and in matter. |
0804.2261 | Joachim Kopp | Joachim Kopp, Toshihiko Ota, Walter Winter | Neutrino factory optimization for non-standard interactions | LaTeX, 30 pages, 7 figures, 1 table | Phys.Rev.D78:053007,2008 | 10.1103/PhysRevD.78.053007 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the optimization of a neutrino factory with respect to non-standard
neutral current neutrino interactions, and compare the results to those
obtained without non-standard interactions. We discuss the muon energy,
baselines, and oscillation channels as degrees of freedom. Our conclusions are
based on both analytical calculations and on a full numerical simulation of the
neutrino factory setup proposed by the international design study (IDS-NF). We
consider all possible non-standard parameters, and include their complex
phases. We identify the impact of the different parameters on the golden,
silver, and disappearance channels. We come to the conclusion that, even in the
presence of non-standard interactions, the performance of the neutrino factory
hardly profits from a silver channel detector, unless the muon energy is
significantly increased compared to the IDS-NF setup. Apart from the
dispensable silver channel detector, we demonstrate that the IDS-NF setup is
close to optimal even if non-standard interactions are considered. We find that
one very long baseline is a key component in the search for non-standard
interactions, in particular for |\epsilon^m_{\mu\tau}| and
|\epsilon^m_{\tau\tau}|.
| [
{
"created": "Tue, 15 Apr 2008 09:35:06 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Kopp",
"Joachim",
""
],
[
"Ota",
"Toshihiko",
""
],
[
"Winter",
"Walter",
""
]
] | We study the optimization of a neutrino factory with respect to non-standard neutral current neutrino interactions, and compare the results to those obtained without non-standard interactions. We discuss the muon energy, baselines, and oscillation channels as degrees of freedom. Our conclusions are based on both analytical calculations and on a full numerical simulation of the neutrino factory setup proposed by the international design study (IDS-NF). We consider all possible non-standard parameters, and include their complex phases. We identify the impact of the different parameters on the golden, silver, and disappearance channels. We come to the conclusion that, even in the presence of non-standard interactions, the performance of the neutrino factory hardly profits from a silver channel detector, unless the muon energy is significantly increased compared to the IDS-NF setup. Apart from the dispensable silver channel detector, we demonstrate that the IDS-NF setup is close to optimal even if non-standard interactions are considered. We find that one very long baseline is a key component in the search for non-standard interactions, in particular for |\epsilon^m_{\mu\tau}| and |\epsilon^m_{\tau\tau}|. |
2401.10979 | Diego Guadagnoli | Mael Cavan-Piton, Diego Guadagnoli, Micaela Oertel, Hyeonseok Seong,
Ludovico Vittorio | Axion emission from strange matter in core-collapse SNe | 10 pages, 2 figures | null | null | LAPTH-006/24, DESY-24-011 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The modification, by exotic sources of cooling, of the neutrino burst's
duration following the core collapse of SN 1987A is known to provide a
formidable constraint on axion interactions with matter. Compton-like
nucleon-pion to nucleon-axion scattering has recently been shown to be an
important mechanism, due to the large baryon and the non-negligible pion
densities in the concerned proto-neutron star volume. In this context, the
question arises of the role of hadronic matter beyond the first generation --
in particular strange matter. We perform a first quantitative study of this
question, by consistently including the full baryon and meson octets in axion
emission from Compton-like scattering and from baryon decay. We consider a
range of possible thermodynamic conditions in the SN as well as various
scenarios for the axion-quark couplings -- among them an "agnostic" scenario
bounded only by data. Irrespective of the scenario considered, we find that
axion emissivity introduces non-trivial correlations between flavour-diagonal
axial couplings and constrains the off-diagonal counterpart to
$O(10^{-1}$-$10^{-2})$ for $f_a = 10^9$ GeV.
| [
{
"created": "Fri, 19 Jan 2024 19:00:00 GMT",
"version": "v1"
}
] | 2024-01-23 | [
[
"Cavan-Piton",
"Mael",
""
],
[
"Guadagnoli",
"Diego",
""
],
[
"Oertel",
"Micaela",
""
],
[
"Seong",
"Hyeonseok",
""
],
[
"Vittorio",
"Ludovico",
""
]
] | The modification, by exotic sources of cooling, of the neutrino burst's duration following the core collapse of SN 1987A is known to provide a formidable constraint on axion interactions with matter. Compton-like nucleon-pion to nucleon-axion scattering has recently been shown to be an important mechanism, due to the large baryon and the non-negligible pion densities in the concerned proto-neutron star volume. In this context, the question arises of the role of hadronic matter beyond the first generation -- in particular strange matter. We perform a first quantitative study of this question, by consistently including the full baryon and meson octets in axion emission from Compton-like scattering and from baryon decay. We consider a range of possible thermodynamic conditions in the SN as well as various scenarios for the axion-quark couplings -- among them an "agnostic" scenario bounded only by data. Irrespective of the scenario considered, we find that axion emissivity introduces non-trivial correlations between flavour-diagonal axial couplings and constrains the off-diagonal counterpart to $O(10^{-1}$-$10^{-2})$ for $f_a = 10^9$ GeV. |
1111.4519 | Yasunori Nomura | Lawrence J. Hall, Yasunori Nomura | Spread Supersymmetry | 20 pages, 5 figures | null | 10.1007/JHEP01(2012)082 | UCB-PTH-11/09 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the multiverse the scale of SUSY breaking, \tilde{m} = F_X/M_*, may scan
and environmental constraints on the dark matter density may exclude a large
range of \tilde{m} from the reheating temperature after inflation down to
values that yield a LSP mass of order a TeV. After selection effects, the
distribution for \tilde{m} may prefer larger values. A single environmental
constraint from dark matter can then lead to multi-component dark matter,
including both axions and the LSP, giving a TeV-scale LSP lighter than the
corresponding value for single-component LSP dark matter.
If SUSY breaking is mediated to the SM sector at order X^* X, only squarks,
sleptons and one Higgs doublet acquire masses of order \tilde{m}. The gravitino
mass is lighter by a factor of M_*/M_Pl and the gaugino masses are suppressed
by a further loop factor. This Spread SUSY spectrum has two versions; the
Higgsino masses are generated in one from supergravity giving a wino LSP and in
the other radiatively giving a Higgsino LSP. The environmental restriction on
dark matter fixes the LSP mass to the TeV domain, so that the squark and
slepton masses are order 10^3 TeV and 10^6 TeV in these two schemes. We study
the spectrum, dark matter and collider signals of these two versions of Spread
SUSY. The Higgs is SM-like and lighter than 145 GeV; monochromatic photons in
cosmic rays arise from dark matter annihilations in the halo; exotic short
charged tracks occur at the LHC, at least for the wino LSP; and there are the
eventual possibilities of direct detection of dark matter and detailed
exploration of the TeV-scale states at a future linear collider. Gauge coupling
unification is as in minimal SUSY theories.
If SUSY breaking is mediated at order X, a much less hierarchical spectrum
results---similar to that of the MSSM, but with the superpartner masses 1--2
orders of magnitude larger than in natural theories.
| [
{
"created": "Sat, 19 Nov 2011 00:07:41 GMT",
"version": "v1"
}
] | 2015-06-03 | [
[
"Hall",
"Lawrence J.",
""
],
[
"Nomura",
"Yasunori",
""
]
] | In the multiverse the scale of SUSY breaking, \tilde{m} = F_X/M_*, may scan and environmental constraints on the dark matter density may exclude a large range of \tilde{m} from the reheating temperature after inflation down to values that yield a LSP mass of order a TeV. After selection effects, the distribution for \tilde{m} may prefer larger values. A single environmental constraint from dark matter can then lead to multi-component dark matter, including both axions and the LSP, giving a TeV-scale LSP lighter than the corresponding value for single-component LSP dark matter. If SUSY breaking is mediated to the SM sector at order X^* X, only squarks, sleptons and one Higgs doublet acquire masses of order \tilde{m}. The gravitino mass is lighter by a factor of M_*/M_Pl and the gaugino masses are suppressed by a further loop factor. This Spread SUSY spectrum has two versions; the Higgsino masses are generated in one from supergravity giving a wino LSP and in the other radiatively giving a Higgsino LSP. The environmental restriction on dark matter fixes the LSP mass to the TeV domain, so that the squark and slepton masses are order 10^3 TeV and 10^6 TeV in these two schemes. We study the spectrum, dark matter and collider signals of these two versions of Spread SUSY. The Higgs is SM-like and lighter than 145 GeV; monochromatic photons in cosmic rays arise from dark matter annihilations in the halo; exotic short charged tracks occur at the LHC, at least for the wino LSP; and there are the eventual possibilities of direct detection of dark matter and detailed exploration of the TeV-scale states at a future linear collider. Gauge coupling unification is as in minimal SUSY theories. If SUSY breaking is mediated at order X, a much less hierarchical spectrum results---similar to that of the MSSM, but with the superpartner masses 1--2 orders of magnitude larger than in natural theories. |
1608.08519 | Ya Zhao | Ya Zhao | Obtaining nonvanishing $\theta_{13}$ with constrained neutrino Yukawa
matrix and implications for flavor model buildings | 10 pages, 2 tables, no figures | null | 10.1142/S0217732317500808 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Assuming a diagonal Majorana neutrino mass matrix, we investigate the
neutrino Yukawa textures which lead to a non-zero reactor mixing angle
$\theta_{13}$. The neutrino effective coupling matrix $\kappa^{eff}$ is
pre-diagonalized by a constant mixing pattern $V_{\nu}$ with a vanishing
$\theta^{\nu}_{13}$. The resulting pre-diagonal symmetrical matrix $\kappa$ is
set to be four texture zeros with two types of off-diagonal elements nonzero,
which is $\kappa_{13}$ and $\kappa_{23}$, respectively. With the expectation of
simple textures we thoroughly classify the linear combinations, $\alpha_{i}$,
$\beta_{i}$ and $\gamma_{i}$ of Yukawa elements $\lambda_{ij}$ in a same row,
according to the values vanishing or not. Each set of the classifications can
lead to a Yukawa texture which may have implications for the discrete flavor
model buildings. We also present a model based on $A_{4}$ according to one set
of the constraints on the three combinations with a specific choice of a
coefficient in Yukawa texture.
| [
{
"created": "Tue, 30 Aug 2016 15:49:27 GMT",
"version": "v1"
}
] | 2017-06-07 | [
[
"Zhao",
"Ya",
""
]
] | Assuming a diagonal Majorana neutrino mass matrix, we investigate the neutrino Yukawa textures which lead to a non-zero reactor mixing angle $\theta_{13}$. The neutrino effective coupling matrix $\kappa^{eff}$ is pre-diagonalized by a constant mixing pattern $V_{\nu}$ with a vanishing $\theta^{\nu}_{13}$. The resulting pre-diagonal symmetrical matrix $\kappa$ is set to be four texture zeros with two types of off-diagonal elements nonzero, which is $\kappa_{13}$ and $\kappa_{23}$, respectively. With the expectation of simple textures we thoroughly classify the linear combinations, $\alpha_{i}$, $\beta_{i}$ and $\gamma_{i}$ of Yukawa elements $\lambda_{ij}$ in a same row, according to the values vanishing or not. Each set of the classifications can lead to a Yukawa texture which may have implications for the discrete flavor model buildings. We also present a model based on $A_{4}$ according to one set of the constraints on the three combinations with a specific choice of a coefficient in Yukawa texture. |
1610.01166 | Matthias Burkardt | Manal Abdallah and Matthias Burkardt | Transverse Force on Transversely Polarized Quarks in Longitudinally
Polarized Nucleons | null | null | 10.1103/PhysRevD.94.094040 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the semi-classical interpretation of the $x^3$ and $x^4$ moments of
twist-3 parton distribution functions (PDFs). While no semi-classical
interpretation for the higher moments of $g_T(x)$ and $e(x)$ was find, the
$x^3$ moment of the chirally odd spin-dependent twist-3 PDF $h_L^3(x)$ can be
related to the longitudinal gradient of the transverse force on transversely
polarized quarks in longitudinally polarized nucleons in a DIS experiment. We
discuss how this result relates to the torque acting on a quark in the same
experiment. This has further implications for comparisons between tha
Jaffe-Manohar and the Ji decompositions of the nucleon spin.
| [
{
"created": "Tue, 4 Oct 2016 20:00:06 GMT",
"version": "v1"
}
] | 2016-12-21 | [
[
"Abdallah",
"Manal",
""
],
[
"Burkardt",
"Matthias",
""
]
] | We study the semi-classical interpretation of the $x^3$ and $x^4$ moments of twist-3 parton distribution functions (PDFs). While no semi-classical interpretation for the higher moments of $g_T(x)$ and $e(x)$ was find, the $x^3$ moment of the chirally odd spin-dependent twist-3 PDF $h_L^3(x)$ can be related to the longitudinal gradient of the transverse force on transversely polarized quarks in longitudinally polarized nucleons in a DIS experiment. We discuss how this result relates to the torque acting on a quark in the same experiment. This has further implications for comparisons between tha Jaffe-Manohar and the Ji decompositions of the nucleon spin. |
hep-ph/0501123 | Nicolas Matagne SE | N. Matagne | Analysis of the $[{\bf 56},4^+]$ Baryon Masses in the $1/N_c$ Expansion | 5 pages, 3 figures, Presented at the JJC2004 -Journees Jeunes
Chercheurs-, ile de Berder, France, 28 November-3 December 2004. One
reference added | null | null | null | hep-ph | null | We use the $1/N_c$ expansion of QCD to analyze the spectrum of positive
parity resonances with strangeness $S = 0, -1, -2$ and -3 in the 2--3 GeV mass
region, supposed to belong to the $[\textbf{56},4^+]$ multiplet. We find that
the spin-spin term brings the dominant contribution and that the spin-orbit
term is entirely negligible in the hyperfine interaction, in agreement with
constituent quark model results. More data are strongly desirable, especially
in the strange sector in order to fully exploit the power of this approach.
| [
{
"created": "Fri, 14 Jan 2005 15:25:46 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Jan 2005 13:57:25 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Matagne",
"N.",
""
]
] | We use the $1/N_c$ expansion of QCD to analyze the spectrum of positive parity resonances with strangeness $S = 0, -1, -2$ and -3 in the 2--3 GeV mass region, supposed to belong to the $[\textbf{56},4^+]$ multiplet. We find that the spin-spin term brings the dominant contribution and that the spin-orbit term is entirely negligible in the hyperfine interaction, in agreement with constituent quark model results. More data are strongly desirable, especially in the strange sector in order to fully exploit the power of this approach. |
hep-ph/0610112 | Andreas Metz | A. Metz, M. Schlegel, and K. Goeke | Transverse single spin asymmetries in inclusive deep-inelastic
scattering | 9 pages, 1 figure, minor changes, final version, to appear in Phys.
Lett. B | Phys.Lett.B643:319-324,2006 | 10.1016/j.physletb.2006.11.009 | null | hep-ph hep-ex | null | In inclusive deep-inelastic lepton-hadron scattering multi-photon exchange
between the leptonic and the hadronic part of the process causes single spin
asymmetries. The asymmetries exist for a polarized target as well as a
polarized incoming or outgoing lepton, if the polarization vector has a
component transverse with respect to the reaction plane. The spin dependent
parts of the single polarized cross sections are suppressed like $\alpha_{em}
m_{pol}/Q$ - where $m_{pol}$ denotes the mass of the polarized particle -
compared to the leading terms of the cross section for unpolarized or
double-polarized deep-inelastic scattering. Both the target and the beam spin
asymmetry are evaluated in the parton model. In the calculation only
quark-quark correlators are included. While this approximation turns out to be
justified for the lepton spin asymmetries, it is not sufficient for the target
asymmetry.
| [
{
"created": "Tue, 10 Oct 2006 16:43:13 GMT",
"version": "v1"
},
{
"created": "Tue, 31 Oct 2006 16:50:47 GMT",
"version": "v2"
},
{
"created": "Tue, 14 Nov 2006 15:49:48 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Metz",
"A.",
""
],
[
"Schlegel",
"M.",
""
],
[
"Goeke",
"K.",
""
]
] | In inclusive deep-inelastic lepton-hadron scattering multi-photon exchange between the leptonic and the hadronic part of the process causes single spin asymmetries. The asymmetries exist for a polarized target as well as a polarized incoming or outgoing lepton, if the polarization vector has a component transverse with respect to the reaction plane. The spin dependent parts of the single polarized cross sections are suppressed like $\alpha_{em} m_{pol}/Q$ - where $m_{pol}$ denotes the mass of the polarized particle - compared to the leading terms of the cross section for unpolarized or double-polarized deep-inelastic scattering. Both the target and the beam spin asymmetry are evaluated in the parton model. In the calculation only quark-quark correlators are included. While this approximation turns out to be justified for the lepton spin asymmetries, it is not sufficient for the target asymmetry. |
hep-ph/0005320 | Oliver Martin | O. Martin and A. Schafer | $\Delta G(x,\mu^2)$ from jet and prompt photon production at RHIC | 21 pages, 10 figures | null | null | null | hep-ph | null | We compare theoretical results for jet and prompt photon production in
polarized pp-collisions at RHIC obained with three different methods: a) the
unpolarized event generator PYTHIA combined with hadronic asymmetry weights
calculated from leading order formulae, b) the polarized event generator SPHINX
which treats the partonic helicity in the hard scattering and the initial state
shower explicitly, and c) parton generators which integrate next-to-leading
order QCD cross sections using Monte Carlo methods. Method a) requires far less
computer time than method b) but we find that it is too imprecise for precision
studies. The lacking treatment of partonic polarization in the initial state
shower results in relative deviations in the asymmetries of up to 20% relative
to SPHINX (method b)). As was to be expected, the event generator predictions
for the absolute cross sections differ significantly from the next-to-leading
order QCD calculations. But fortunately the asymmetries show a much better
agreement: relative deviations for prompt photon production for
parameterizations with medium and large $\Delta g(x,\mu^2)$ barely exceed 10%.
After fine tuning the parameters of the parton showers the same result can be
obtained for jet production.
| [
{
"created": "Wed, 31 May 2000 14:07:05 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Martin",
"O.",
""
],
[
"Schafer",
"A.",
""
]
] | We compare theoretical results for jet and prompt photon production in polarized pp-collisions at RHIC obained with three different methods: a) the unpolarized event generator PYTHIA combined with hadronic asymmetry weights calculated from leading order formulae, b) the polarized event generator SPHINX which treats the partonic helicity in the hard scattering and the initial state shower explicitly, and c) parton generators which integrate next-to-leading order QCD cross sections using Monte Carlo methods. Method a) requires far less computer time than method b) but we find that it is too imprecise for precision studies. The lacking treatment of partonic polarization in the initial state shower results in relative deviations in the asymmetries of up to 20% relative to SPHINX (method b)). As was to be expected, the event generator predictions for the absolute cross sections differ significantly from the next-to-leading order QCD calculations. But fortunately the asymmetries show a much better agreement: relative deviations for prompt photon production for parameterizations with medium and large $\Delta g(x,\mu^2)$ barely exceed 10%. After fine tuning the parameters of the parton showers the same result can be obtained for jet production. |
hep-ph/9512368 | Sugiyama Naoshi | M. Kawasaki, Naoshi Sugiyama and T. Yanagida | Isocurvature and Adiabatic Fluctuations of Axion in Chaotic Inflation
Models and Large Scale Structure | 5 pages, uudecoded postscript file with figures | Phys.Rev.D54:2442-2446,1996 | 10.1103/PhysRevD.54.2442 | UTAP-224, RESCEU-19/95, UT-736 | hep-ph astro-ph | null | In the chaotic inflation models, quantum fluctuations for axion fields lead
to the overproduction of domain walls and too large isocurvature fluctuations
which is inconsistent with the observations of cosmic microwave background
anisotropies. These problems are solved by assuming a very flat potential for
the Peccei-Quinn scalar. As the simplest possibility, we consider a model where
the Peccei-Quinn scalar is an inflaton itself and show that the isocurvature
fluctuations can be comparable with the adiabatic ones. We investigate
cosmological implications in the case that both adiabatic and isocurvature
fluctuations exist and find that the amplitude of the matter spectrum becomes
smaller than that for the pure adiabatic case. This leads to relatively high
bias parameter ($b \simeq 2$) which is favoured by the current observations.
| [
{
"created": "Wed, 20 Dec 1995 06:25:55 GMT",
"version": "v1"
}
] | 2009-12-30 | [
[
"Kawasaki",
"M.",
""
],
[
"Sugiyama",
"Naoshi",
""
],
[
"Yanagida",
"T.",
""
]
] | In the chaotic inflation models, quantum fluctuations for axion fields lead to the overproduction of domain walls and too large isocurvature fluctuations which is inconsistent with the observations of cosmic microwave background anisotropies. These problems are solved by assuming a very flat potential for the Peccei-Quinn scalar. As the simplest possibility, we consider a model where the Peccei-Quinn scalar is an inflaton itself and show that the isocurvature fluctuations can be comparable with the adiabatic ones. We investigate cosmological implications in the case that both adiabatic and isocurvature fluctuations exist and find that the amplitude of the matter spectrum becomes smaller than that for the pure adiabatic case. This leads to relatively high bias parameter ($b \simeq 2$) which is favoured by the current observations. |
1203.1157 | Jordy Vries de | C.-P. Liu, J. de Vries, E. Mereghetti, R. G. E. Timmermans, and U. van
Kolck | Deuteron Magnetic Quadrupole Moment From Chiral Effective Field Theory | null | Phys.Lett.B713:447-452,2012 | 10.1016/j.physletb.2012.06.024 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the magnetic quadrupole moment (MQM) of the deuteron at leading
order in the systematic expansion provided by chiral effective field theory. We
take into account parity and time-reversal violation which, at the quark-gluon
level, results from the QCD vacuum angle and dimension-six operators that
originate from physics beyond the Standard Model. We show that the deuteron MQM
can be expressed in terms of five low-energy constants that appear in the
parity- and time-reversal-violating nuclear potential and electromagnetic
current, four of which also contribute to the electric dipole moments of light
nuclei. We conclude that the deuteron MQM has an enhanced sensitivity to the
QCD vacuum angle and that its measurement would be complementary to the
proposed measurements of light-nuclear EDMs.
| [
{
"created": "Tue, 6 Mar 2012 10:23:19 GMT",
"version": "v1"
}
] | 2012-07-10 | [
[
"Liu",
"C. -P.",
""
],
[
"de Vries",
"J.",
""
],
[
"Mereghetti",
"E.",
""
],
[
"Timmermans",
"R. G. E.",
""
],
[
"van Kolck",
"U.",
""
]
] | We calculate the magnetic quadrupole moment (MQM) of the deuteron at leading order in the systematic expansion provided by chiral effective field theory. We take into account parity and time-reversal violation which, at the quark-gluon level, results from the QCD vacuum angle and dimension-six operators that originate from physics beyond the Standard Model. We show that the deuteron MQM can be expressed in terms of five low-energy constants that appear in the parity- and time-reversal-violating nuclear potential and electromagnetic current, four of which also contribute to the electric dipole moments of light nuclei. We conclude that the deuteron MQM has an enhanced sensitivity to the QCD vacuum angle and that its measurement would be complementary to the proposed measurements of light-nuclear EDMs. |
hep-ph/9408235 | null | I.I. Bigi | Open Questions in Charm Decays Deserving an Answer | 9 pages, LATEX, preprint CERN-TH.7370/94 | null | null | null | hep-ph | null | A list is given of those open questions concerning the dynamics of charm
decays where there exists a strong need for an answer. Such a need is based on
lessons to be learnt about QCD -- either in their own right or for a better
understanding of $B$ physics -- or on searches for New Physics with a small
background from the Standard Model. The major items on this list are: lifetimes
of the $\Xi _c^{0,+}$ baryons; semileptonic branching ratios of $D_s$, $\Lambda
_c$ and $\Xi _c$ hadrons and absolute branching ratios for those states;
radiative decays $D\rightarrow \gamma K^*,\, \gamma \rho /\omega , \, D_s
\rightarrow \gamma \phi /\omega ,\, D\rightarrow l^+l^-K/K^*$; $D^0-\bar D^0$
oscillations down to a sensitivity below $10^{-4}$ and CP asymmetries in
non-leptonic $D$ decays down to 0.1\%. Ongoing and already approved experiments
will produce important new insights, which are unlikely to provide sufficient
answers to all these questions yet. It is discussed how a third-generation
fixed-target experiment like CHARM2000 or a $\tau$-charm factory can fill the
bill.
| [
{
"created": "Thu, 4 Aug 1994 21:27:50 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bigi",
"I. I.",
""
]
] | A list is given of those open questions concerning the dynamics of charm decays where there exists a strong need for an answer. Such a need is based on lessons to be learnt about QCD -- either in their own right or for a better understanding of $B$ physics -- or on searches for New Physics with a small background from the Standard Model. The major items on this list are: lifetimes of the $\Xi _c^{0,+}$ baryons; semileptonic branching ratios of $D_s$, $\Lambda _c$ and $\Xi _c$ hadrons and absolute branching ratios for those states; radiative decays $D\rightarrow \gamma K^*,\, \gamma \rho /\omega , \, D_s \rightarrow \gamma \phi /\omega ,\, D\rightarrow l^+l^-K/K^*$; $D^0-\bar D^0$ oscillations down to a sensitivity below $10^{-4}$ and CP asymmetries in non-leptonic $D$ decays down to 0.1\%. Ongoing and already approved experiments will produce important new insights, which are unlikely to provide sufficient answers to all these questions yet. It is discussed how a third-generation fixed-target experiment like CHARM2000 or a $\tau$-charm factory can fill the bill. |
hep-ph/0001306 | Morimitsu Tanimoto | Morimitsu Tanimoto | Large Mixing Angle MSW Solution in S_3 Flavor Symmetry | 14 pages, LaTex file, 1 figure | Phys.Lett. B483 (2000) 417-424 | 10.1016/S0370-2693(00)00550-5 | EHU-00-01 | hep-ph | null | We have investigated phenomenological implications on the neutrino flavor
mixings in the $S_{3L}\times S_{3R}$ symmetric mass matrices including symmetry
breaking terms. We have shown how to get the large mixing angle MSW solution,
$\sin^2 2 \th_\odot=0.65\sim 0.97$ and $\Delta m_{\odot}^2= 10^{-5}\sim
10^{-4}\eV^2$, in this model. It is found that the structure of the lepton mass
matrix in our model is stable against radiative corrections although the model
leads to nearly degenerate neutrinos.
| [
{
"created": "Sat, 29 Jan 2000 06:46:52 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Tanimoto",
"Morimitsu",
""
]
] | We have investigated phenomenological implications on the neutrino flavor mixings in the $S_{3L}\times S_{3R}$ symmetric mass matrices including symmetry breaking terms. We have shown how to get the large mixing angle MSW solution, $\sin^2 2 \th_\odot=0.65\sim 0.97$ and $\Delta m_{\odot}^2= 10^{-5}\sim 10^{-4}\eV^2$, in this model. It is found that the structure of the lepton mass matrix in our model is stable against radiative corrections although the model leads to nearly degenerate neutrinos. |
hep-ph/0510375 | M Vepsalainen | A. Gynther, M. Vepsalainen | Pressure of the Standard Model at High Temperatures | 30 pages, 4 figures. v2: one reference added, minor revisions,
accepted for publication in JHEP | JHEP 0601:060,2006 | 10.1088/1126-6708/2006/01/060 | HIP-2005-46/TH | hep-ph | null | We compute the pressure of the standard model at high temperatures in the
symmetric phase to three loops, or to O(g^5) in all coupling constants. We find
that the terms of the perturbative expansion in the SU(2) + Higgs sector
decrease monotonically with increasing order, but the large values of the
strong coupling constant g_s and the Yukawa coupling of the top quark g_Y make
the expansion in the full theory converge more slowly. The final result is
observed to be about 10% smaller than the ideal gas pressure commonly used in
cosmological calculations.
| [
{
"created": "Fri, 28 Oct 2005 11:12:05 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Dec 2005 11:43:53 GMT",
"version": "v2"
}
] | 2011-01-13 | [
[
"Gynther",
"A.",
""
],
[
"Vepsalainen",
"M.",
""
]
] | We compute the pressure of the standard model at high temperatures in the symmetric phase to three loops, or to O(g^5) in all coupling constants. We find that the terms of the perturbative expansion in the SU(2) + Higgs sector decrease monotonically with increasing order, but the large values of the strong coupling constant g_s and the Yukawa coupling of the top quark g_Y make the expansion in the full theory converge more slowly. The final result is observed to be about 10% smaller than the ideal gas pressure commonly used in cosmological calculations. |
2305.09440 | Xavier Ponce Diaz | Luca Di Luzio, Alfredo Walter Mario Guerrera, Xavier Ponce D\'iaz,
Stefano Rigolin | UV-IR interplay in axion flavour violation | 4 pages, 1 figure, contribution to the 2023 Electroweak session of
the 57th Rencontres de Moriond | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Flavour-violating axions appear in models where the Peccei-Quinn(PQ) charges
are generation non-universal. Consequently, this charge arrangement will also
generate flavour violation in the UV sector. The typical way of implementing
such an axion in a UV completion is with a DFSZ model, containing 2 Higgs
doublets. In this talk we will present how to parameterize the flavour
violation in the UV such that we can find a direct correlation with the flavour
violation of the axion. Finally, we show in an example how this connection can
help in giving information about the UV completion if an axion is found in a
flavour-violating channel.
| [
{
"created": "Tue, 16 May 2023 13:57:37 GMT",
"version": "v1"
}
] | 2023-05-17 | [
[
"Di Luzio",
"Luca",
""
],
[
"Guerrera",
"Alfredo Walter Mario",
""
],
[
"Díaz",
"Xavier Ponce",
""
],
[
"Rigolin",
"Stefano",
""
]
] | Flavour-violating axions appear in models where the Peccei-Quinn(PQ) charges are generation non-universal. Consequently, this charge arrangement will also generate flavour violation in the UV sector. The typical way of implementing such an axion in a UV completion is with a DFSZ model, containing 2 Higgs doublets. In this talk we will present how to parameterize the flavour violation in the UV such that we can find a direct correlation with the flavour violation of the axion. Finally, we show in an example how this connection can help in giving information about the UV completion if an axion is found in a flavour-violating channel. |
2302.00642 | Oleksandr Tomalak | Oleksandr Tomalak | Radiative corrections to neutron beta decay and (anti)neutrino-nucleon
scattering from low-energy effective field theory | 19 pages, 3 figures | Few-Body Syst 64, 23 (2023) | 10.1007/s00601-023-01802-3 | LA-UR-23-20003 | hep-ph nucl-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | We study radiative corrections to neutron beta decay and low-energy
(anti)neutrino-nucleon scattering within a top-down effective field theory
approach. As it was recently shown, a few electromagnetic and electroweak
low-energy coupling constants in heavy-baryon chiral perturbation theory are
yet to be determined. Performing matching to the four-fermion effective field
theory, we relate these low-energy constants to correlation functions of vector
and axial-vector currents. Such relations allow us to explicitly clarify scheme
dependence for radiative corrections to neutron decay and low-energy
charged-current (anti)neutrino scattering, provide a robust prediction of
leading in the electromagnetic coupling constant contributions, and achieve a
clear separation between short-distance and long-distance contributions.
| [
{
"created": "Wed, 1 Feb 2023 18:12:15 GMT",
"version": "v1"
},
{
"created": "Sat, 29 Apr 2023 23:43:02 GMT",
"version": "v2"
}
] | 2023-05-02 | [
[
"Tomalak",
"Oleksandr",
""
]
] | We study radiative corrections to neutron beta decay and low-energy (anti)neutrino-nucleon scattering within a top-down effective field theory approach. As it was recently shown, a few electromagnetic and electroweak low-energy coupling constants in heavy-baryon chiral perturbation theory are yet to be determined. Performing matching to the four-fermion effective field theory, we relate these low-energy constants to correlation functions of vector and axial-vector currents. Such relations allow us to explicitly clarify scheme dependence for radiative corrections to neutron decay and low-energy charged-current (anti)neutrino scattering, provide a robust prediction of leading in the electromagnetic coupling constant contributions, and achieve a clear separation between short-distance and long-distance contributions. |
1408.5104 | Olivier Pene | Alain Le Yaouanc and Olivier Pene | In Memoriam Nikolai Uraltsev : Uraltsev's and other Sum Rules, Theory
and Phenomenology of $D^{**}$'s | 21 pages, one figure, contribution to a book in Memoriam Nikolai
Uraltsev | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We first discuss Uraltsev's and other sum rules constraining the $B \to
D^{**}(L=1)$ weak transitions in the infinite mass limit, and compare them with
dynamical approaches in the same limit. After recalling these well established
facts, we discuss how to apply infinite mass limit to the physical situation.
We provide predictions concerning semi-leptonic decays and non-leptonic ones,
based on quark models. We then present in more detail the dynamical approaches:
the relativistic quark model \`a la Bakamjian-Thomas and lattice QCD. We
summarise lattice QCD results in the infinite mass limit and compare them to
the quark model predictions. We then present preliminary lattice QCD results
with finite $b$ and $c$ quark masses. A systematic comparison between theory
and experiment is performed. We show that some large discrepancies exist
between different experiments. Altogether the predictions at infinite mass are
in fair agreement with experiment for non-leptonic decays contrary to what
happens for semileptonic decays. We conclude by considering the prospects to
clarify both the experimental situation, the theoretical one and the comparison
between both.
| [
{
"created": "Thu, 21 Aug 2014 18:41:22 GMT",
"version": "v1"
}
] | 2014-08-22 | [
[
"Yaouanc",
"Alain Le",
""
],
[
"Pene",
"Olivier",
""
]
] | We first discuss Uraltsev's and other sum rules constraining the $B \to D^{**}(L=1)$ weak transitions in the infinite mass limit, and compare them with dynamical approaches in the same limit. After recalling these well established facts, we discuss how to apply infinite mass limit to the physical situation. We provide predictions concerning semi-leptonic decays and non-leptonic ones, based on quark models. We then present in more detail the dynamical approaches: the relativistic quark model \`a la Bakamjian-Thomas and lattice QCD. We summarise lattice QCD results in the infinite mass limit and compare them to the quark model predictions. We then present preliminary lattice QCD results with finite $b$ and $c$ quark masses. A systematic comparison between theory and experiment is performed. We show that some large discrepancies exist between different experiments. Altogether the predictions at infinite mass are in fair agreement with experiment for non-leptonic decays contrary to what happens for semileptonic decays. We conclude by considering the prospects to clarify both the experimental situation, the theoretical one and the comparison between both. |
2109.07376 | Igor G. Irastorza | Igor G. Irastorza | An introduction to axions and their detection | Submitted to SciPost Physics Lecture Notes, Les Houches Summer School
Series. Second version after referees comments | SciPost Phys. Lect. Notes 45 (2022) | 10.21468/SciPostPhysLectNotes.45 | null | hep-ph astro-ph.SR hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In these notes I try to introduce the reader to the topic of axions: their
theoretical motivation and expected phenomenology, their role in astrophysics
and as dark matter candidate, and the experimental techniques to detect them.
Special emphasis is made in this last point, for which a relatively updated
review of worldwide efforts and future prospects is made. The material is
intended as an introduction to the topic, and it was prepared as lecture notes
for Les Houches summer school 2021. Abundant references are included to direct
the reader to deeper insight on the different aspects of axion physics.
| [
{
"created": "Wed, 15 Sep 2021 15:33:54 GMT",
"version": "v1"
},
{
"created": "Fri, 5 Nov 2021 23:06:03 GMT",
"version": "v2"
}
] | 2022-03-30 | [
[
"Irastorza",
"Igor G.",
""
]
] | In these notes I try to introduce the reader to the topic of axions: their theoretical motivation and expected phenomenology, their role in astrophysics and as dark matter candidate, and the experimental techniques to detect them. Special emphasis is made in this last point, for which a relatively updated review of worldwide efforts and future prospects is made. The material is intended as an introduction to the topic, and it was prepared as lecture notes for Les Houches summer school 2021. Abundant references are included to direct the reader to deeper insight on the different aspects of axion physics. |
0906.1742 | Hans-Peter Morsch | H.P. Morsch | Hadron mass generation and the strong interaction | Improved version giving details on the sensitivity of the
self-consistency requirement in eq.(7) and on the application of the vacuum
potential sum rule in eq.(13) | PoS EPS-HEP2009:084,2009 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based on a Lagrangian with a coupling of two gluons to J^pi=0^+ (the quantum
numbers of the vacuum) which decay to q-qbar pairs, a model is presented, in
which hadrons couple directly to the absolute vacuum of fluctuating gluon
fields. By self-consistency requirements the confinement potential as well as
hadron densities and masses are obtained, which are in good agreement with
experimental data on scalar and vector mesons. In comparison with potential
models additional states are predicted, which can explain the large continuum
of scalar states in the low mass spectrum and new states in the charm region.
The present model is consistent with the concept, that the hadron masses can be
understood by binding effects of the quarks.
| [
{
"created": "Tue, 9 Jun 2009 14:25:22 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Jul 2009 15:45:50 GMT",
"version": "v2"
},
{
"created": "Fri, 2 Oct 2009 08:56:37 GMT",
"version": "v3"
}
] | 2014-11-20 | [
[
"Morsch",
"H. P.",
""
]
] | Based on a Lagrangian with a coupling of two gluons to J^pi=0^+ (the quantum numbers of the vacuum) which decay to q-qbar pairs, a model is presented, in which hadrons couple directly to the absolute vacuum of fluctuating gluon fields. By self-consistency requirements the confinement potential as well as hadron densities and masses are obtained, which are in good agreement with experimental data on scalar and vector mesons. In comparison with potential models additional states are predicted, which can explain the large continuum of scalar states in the low mass spectrum and new states in the charm region. The present model is consistent with the concept, that the hadron masses can be understood by binding effects of the quarks. |
1102.1932 | Azadeh Maleknejad | A. Maleknejad and M.M. Sheikh-Jabbari | Non-Abelian Gauge Field Inflation | 49 pages, 23 figures. v5: Cosmic perturbation analysis improved | Phys.Rev.D84:043515,2011 | 10.1103/PhysRevD.84.043515 | IPM/P-2010/009 | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In [arXiv:1102.1513] we introduced an inflationary scenario, Non-Abelian
Gauge Field Inflation or gauge-flation for short, in which slow-roll inflation
is driven by non-Abelian gauge field minimally coupled to gravity. We present a
more detailed analysis, both numerical and analytical, of the gauge-flation. By
studying the phase diagrams of the theory, we show that getting enough number
of e-folds during a slow-roll inflation is fairly robust to the choice of
initial gauge field values. In addition, we present a detailed analysis of the
cosmic perturbation theory in gauge-flation which has many special and
interesting features compared the standard scalar-driven inflationary models.
The specific gauge-flation model we study in this paper has two parameters, a
cutoff scale Lambda and the gauge coupling g. Fitting our results with the
current cosmological data fixes \Lambda\sim 10 H \sim 10^{15} GeV (H is the
Hubble parameter) and g\sim 10^{-4}, which are in the natural range of
parameters in generic particle physics beyond standard models. Our model also
predicts a tensor-to-scalar ratio r>0.05, in the range detectable by the Planck
satellite.
| [
{
"created": "Wed, 9 Feb 2011 18:33:10 GMT",
"version": "v1"
},
{
"created": "Sun, 20 Feb 2011 10:15:20 GMT",
"version": "v2"
},
{
"created": "Wed, 18 May 2011 05:47:38 GMT",
"version": "v3"
},
{
"created": "Mon, 8 Aug 2011 11:59:13 GMT",
"version": "v4"
},
{
"cre... | 2015-03-18 | [
[
"Maleknejad",
"A.",
""
],
[
"Sheikh-Jabbari",
"M. M.",
""
]
] | In [arXiv:1102.1513] we introduced an inflationary scenario, Non-Abelian Gauge Field Inflation or gauge-flation for short, in which slow-roll inflation is driven by non-Abelian gauge field minimally coupled to gravity. We present a more detailed analysis, both numerical and analytical, of the gauge-flation. By studying the phase diagrams of the theory, we show that getting enough number of e-folds during a slow-roll inflation is fairly robust to the choice of initial gauge field values. In addition, we present a detailed analysis of the cosmic perturbation theory in gauge-flation which has many special and interesting features compared the standard scalar-driven inflationary models. The specific gauge-flation model we study in this paper has two parameters, a cutoff scale Lambda and the gauge coupling g. Fitting our results with the current cosmological data fixes \Lambda\sim 10 H \sim 10^{15} GeV (H is the Hubble parameter) and g\sim 10^{-4}, which are in the natural range of parameters in generic particle physics beyond standard models. Our model also predicts a tensor-to-scalar ratio r>0.05, in the range detectable by the Planck satellite. |
1708.02679 | Eric S. Swanson | Richard F. Lebed and Eric S. Swanson | Heavy-Quark Hybrid Mass Splittings: Hyperfine and "Ultrafine" | Version to appear in Few-Body Systems. Substantial modifications from
previous version, including extensive additional references and an expanded
discussion of relevant operators. 7 pages | null | 10.1007/s00601-018-1376-9 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is argued that the heavy-quark limit of QCD requires a certain combination
of hyperfine mass splittings in heavy-quark hybrid-meson multiplets to be
unusually small. This observation will assist in the exploration of the
heavy-quark hybrid spectrum at facilities such as PANDA. Alternatively, a large
measured value for this mass splitting indicates that at least one member of
the multiplet must contain significant light-quark degrees of freedom.
| [
{
"created": "Tue, 8 Aug 2017 23:53:37 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Apr 2018 02:07:02 GMT",
"version": "v2"
}
] | 2022-10-19 | [
[
"Lebed",
"Richard F.",
""
],
[
"Swanson",
"Eric S.",
""
]
] | It is argued that the heavy-quark limit of QCD requires a certain combination of hyperfine mass splittings in heavy-quark hybrid-meson multiplets to be unusually small. This observation will assist in the exploration of the heavy-quark hybrid spectrum at facilities such as PANDA. Alternatively, a large measured value for this mass splitting indicates that at least one member of the multiplet must contain significant light-quark degrees of freedom. |
1502.07682 | Andreea Georgescu | Eugenio Del Nobile, Graciela B. Gelmini, Andreea Georgescu, and
Ji-Haeng Huh | Reevaluation of spin-dependent WIMP-proton interactions as an
explanation of the DAMA data | Section on halo-independent analysis added and other small changes in
the SHM data analysis made | null | 10.1088/1475-7516/2015/08/046 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We reexamine the interpretation of the annual modulation signal observed by
the DAMA experiment as due to WIMPs with a spin-dependent coupling mostly to
protons. We consider both axial-vector and pseudo-scalar couplings, and elastic
as well as endothermic and exothermic inelastic scattering. We conclude that
the DAMA signal is in strong tension with null results of other direct
detection experiments, particularly PICASSO and KIMS.
| [
{
"created": "Thu, 26 Feb 2015 19:02:38 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Jul 2015 23:27:26 GMT",
"version": "v2"
}
] | 2015-09-16 | [
[
"Del Nobile",
"Eugenio",
""
],
[
"Gelmini",
"Graciela B.",
""
],
[
"Georgescu",
"Andreea",
""
],
[
"Huh",
"Ji-Haeng",
""
]
] | We reexamine the interpretation of the annual modulation signal observed by the DAMA experiment as due to WIMPs with a spin-dependent coupling mostly to protons. We consider both axial-vector and pseudo-scalar couplings, and elastic as well as endothermic and exothermic inelastic scattering. We conclude that the DAMA signal is in strong tension with null results of other direct detection experiments, particularly PICASSO and KIMS. |
1201.3956 | Seung-il Nam | Seung-il Nam | Heavy pseudoscalar-meson decay constants with strangeness from the
extended nonlocal chiral-quark model | 12 pages, 7 figures, accepted for publication in Mod. Phys. Lett. A | null | 10.1142/S0217732312501532 | KIAS-P12007 | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the weak-decay constants for the heavy pseudoscalar mesons, D, Ds,
B, and Bs. For this purpose, we employ the extended nonlocal chiral-quark model
(ExNLChQM), motivated by the heavy-quark effective field theory as well as the
instanton-vacuum configuration. In addition to the heavy-quark symmetry and the
nonlocal interactions between quarks and pseudoscalar mesons in ExNLChQM, a
correction for the strange-quark content inside Ds and Bs is also taken into
account and found to be crucial to reproduce the empirical values. From those
numerical results, we obtain f_{D,Ds,B,Bs}=(207.53, 262.56, 208.13, 262.39)
MeV, which are in good agreement with experimental data and other theoretical
estimations. Using those numerical results, we compute the CKM matrix elements
and the Cabibbo angle, using various mesonic and leptonic heavy-meson decay
channels, resulting in
(|V_{cd}|,|V_{cs}|,|V_{ub}|,|V_{td}|/|V_{ts}|)=(0.224,0.968,<5.395*10^{-3},0.215)
and theta_C=12.36^o which are well compatible with available data.
| [
{
"created": "Thu, 19 Jan 2012 01:07:04 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Aug 2012 02:29:46 GMT",
"version": "v2"
}
] | 2012-08-17 | [
[
"Nam",
"Seung-il",
""
]
] | We study the weak-decay constants for the heavy pseudoscalar mesons, D, Ds, B, and Bs. For this purpose, we employ the extended nonlocal chiral-quark model (ExNLChQM), motivated by the heavy-quark effective field theory as well as the instanton-vacuum configuration. In addition to the heavy-quark symmetry and the nonlocal interactions between quarks and pseudoscalar mesons in ExNLChQM, a correction for the strange-quark content inside Ds and Bs is also taken into account and found to be crucial to reproduce the empirical values. From those numerical results, we obtain f_{D,Ds,B,Bs}=(207.53, 262.56, 208.13, 262.39) MeV, which are in good agreement with experimental data and other theoretical estimations. Using those numerical results, we compute the CKM matrix elements and the Cabibbo angle, using various mesonic and leptonic heavy-meson decay channels, resulting in (|V_{cd}|,|V_{cs}|,|V_{ub}|,|V_{td}|/|V_{ts}|)=(0.224,0.968,<5.395*10^{-3},0.215) and theta_C=12.36^o which are well compatible with available data. |
1503.04071 | Ferruccio Feruglio | Ferruccio Feruglio | Pieces of the Flavour Puzzle | 26 pages, 7 figures | null | 10.1140/epjc/s10052-015-3576-5 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An overview of the flavour problem is presented, with emphasis on the
theoretical efforts to find a satisfactory description of fermion masses and
mixing angles.
| [
{
"created": "Fri, 13 Mar 2015 14:06:21 GMT",
"version": "v1"
}
] | 2015-09-30 | [
[
"Feruglio",
"Ferruccio",
""
]
] | An overview of the flavour problem is presented, with emphasis on the theoretical efforts to find a satisfactory description of fermion masses and mixing angles. |
2212.07559 | Lachlan Morris | Peter Athron, Csaba Bal\'azs, Lachlan Morris | Supercool subtleties of cosmological phase transitions | 39 pages (46 with appendices), 8 figures | null | 10.1088/1475-7516/2023/03/006 | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | We investigate rarely explored details of supercooled cosmological
first-order phase transitions at the electroweak scale, which may lead to
strong gravitational wave signals or explain the cosmic baryon asymmetry. The
nucleation temperature is often used in phase transition analyses, and is
defined through the nucleation condition: on average one bubble has nucleated
per Hubble volume. We argue that the nucleation temperature is neither a
fundamental nor essential quantity in phase transition analysis. We illustrate
scenarios where a transition can complete without satisfying the nucleation
condition, and conversely where the nucleation condition is satisfied but the
transition does not complete. We also find that simple nucleation heuristics,
which are defined to approximate the nucleation temperature, break down for
strong supercooling. Thus, studies that rely on the nucleation temperature
$\unicode{x2014}$ approximated or otherwise $\unicode{x2014}$ may misclassify
the completion of a transition. Further, we find that the nucleation
temperature decouples from the progress of the transition for strong
supercooling. We advocate use of the percolation temperature as a reference
temperature for gravitational wave production, because the percolation
temperature is directly connected to transition progress and the collision of
bubbles. Finally, we provide model-independent bounds on the bubble wall
velocity that allow one to predict whether a transition completes based only on
knowledge of the bounce action curve. We apply our methods to find empirical
bounds on the bubble wall velocity for which the physical volume of the false
vacuum decreases during the transition. We verify the accuracy of our
predictions using benchmarks from a high temperature expansion of the Standard
Model and from the real scalar singlet model.
| [
{
"created": "Thu, 15 Dec 2022 00:20:07 GMT",
"version": "v1"
}
] | 2023-03-08 | [
[
"Athron",
"Peter",
""
],
[
"Balázs",
"Csaba",
""
],
[
"Morris",
"Lachlan",
""
]
] | We investigate rarely explored details of supercooled cosmological first-order phase transitions at the electroweak scale, which may lead to strong gravitational wave signals or explain the cosmic baryon asymmetry. The nucleation temperature is often used in phase transition analyses, and is defined through the nucleation condition: on average one bubble has nucleated per Hubble volume. We argue that the nucleation temperature is neither a fundamental nor essential quantity in phase transition analysis. We illustrate scenarios where a transition can complete without satisfying the nucleation condition, and conversely where the nucleation condition is satisfied but the transition does not complete. We also find that simple nucleation heuristics, which are defined to approximate the nucleation temperature, break down for strong supercooling. Thus, studies that rely on the nucleation temperature $\unicode{x2014}$ approximated or otherwise $\unicode{x2014}$ may misclassify the completion of a transition. Further, we find that the nucleation temperature decouples from the progress of the transition for strong supercooling. We advocate use of the percolation temperature as a reference temperature for gravitational wave production, because the percolation temperature is directly connected to transition progress and the collision of bubbles. Finally, we provide model-independent bounds on the bubble wall velocity that allow one to predict whether a transition completes based only on knowledge of the bounce action curve. We apply our methods to find empirical bounds on the bubble wall velocity for which the physical volume of the false vacuum decreases during the transition. We verify the accuracy of our predictions using benchmarks from a high temperature expansion of the Standard Model and from the real scalar singlet model. |
1605.08663 | Mikael Chala | Mikael Chala, Germano Nardini and Ivan Sobolev | A unified explanation for dark matter and electroweak baryogenesis with
direct detection and gravitational wave signatures | 10 pages, 5 figures. V2: discussion on runaway condition clarified,
refs added, typos fixed | Phys. Rev. D 94, 055006 (2016) | 10.1103/PhysRevD.94.055006 | DESY 16-092 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | A minimal extension of the Standard Model that provides both a dark matter
candidate and a strong first-order electroweak phase transition (EWPT) consists
of two additional Lorentz and gauge singlets. In this paper we work out a
composite Higgs version of this scenario, based on the coset $SO(7)/SO(6)$. We
show that by embedding the elementary fermions in appropriate representations
of $SO(7)$, all dominant interactions are described by only three free
effective parameters. Within the model dependencies of the embedding, the
theory predicts one of the singlets to be stable and responsible for the
observed dark matter abundance. At the same time, the second singlet introduces
new $CP$-violation phases and triggers a strong first-order EWPT, making
electroweak baryogenesis feasible. It turns out that this scenario does not
conflict with current observations and it is promising for solving the dark
matter and baryon asymmetry puzzles. The tight predictions of the model will be
accessible at the forthcoming dark matter direct detection and gravitational
wave experiments.
| [
{
"created": "Fri, 27 May 2016 14:30:11 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Jul 2016 09:29:29 GMT",
"version": "v2"
}
] | 2016-09-14 | [
[
"Chala",
"Mikael",
""
],
[
"Nardini",
"Germano",
""
],
[
"Sobolev",
"Ivan",
""
]
] | A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite Higgs version of this scenario, based on the coset $SO(7)/SO(6)$. We show that by embedding the elementary fermions in appropriate representations of $SO(7)$, all dominant interactions are described by only three free effective parameters. Within the model dependencies of the embedding, the theory predicts one of the singlets to be stable and responsible for the observed dark matter abundance. At the same time, the second singlet introduces new $CP$-violation phases and triggers a strong first-order EWPT, making electroweak baryogenesis feasible. It turns out that this scenario does not conflict with current observations and it is promising for solving the dark matter and baryon asymmetry puzzles. The tight predictions of the model will be accessible at the forthcoming dark matter direct detection and gravitational wave experiments. |
2111.07563 | Manu Kurian | Avdhesh Kumar, Manu Kurian, Santosh K. Das, Vinod Chandra | Dragging heavy quark in an anisotropic QCD medium beyond the static
limit | 9 pages, 4 figures | Phys. Rev. C 105 (2022) 5, 054903 | 10.1103/PhysRevC.105.054903 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Heavy quark dynamics in an anisotropic QCD medium have been analyzed within
the Fokker-Planck approach. Heavy quark drag force and momentum diffusion
tensor have been decomposed by employing a general tensor basis for an
anisotropic medium. Depending upon the relative orientation of the direction of
the momentum anisotropy of the medium and heavy quark motion, two drag and four
diffusion coefficients have been estimated in the anisotropic QCD medium. The
relative significance of different components of drag and momentum diffusion
coefficients has been explored. The dependence of the angle between the
anisotropic vector and heavy quark motion to the drag and diffusion
coefficients has also been studied. Further, the energy loss of heavy quarks
due to the elastic collisional process in an anisotropic medium has been
studied. It is seen that the anisotropic contributions to heavy quark transport
coefficients and its collisional energy loss have a strong dependence on the
direction and strength of momentum anisotropy in the QCD medium.
| [
{
"created": "Mon, 15 Nov 2021 07:27:14 GMT",
"version": "v1"
}
] | 2022-05-13 | [
[
"Kumar",
"Avdhesh",
""
],
[
"Kurian",
"Manu",
""
],
[
"Das",
"Santosh K.",
""
],
[
"Chandra",
"Vinod",
""
]
] | Heavy quark dynamics in an anisotropic QCD medium have been analyzed within the Fokker-Planck approach. Heavy quark drag force and momentum diffusion tensor have been decomposed by employing a general tensor basis for an anisotropic medium. Depending upon the relative orientation of the direction of the momentum anisotropy of the medium and heavy quark motion, two drag and four diffusion coefficients have been estimated in the anisotropic QCD medium. The relative significance of different components of drag and momentum diffusion coefficients has been explored. The dependence of the angle between the anisotropic vector and heavy quark motion to the drag and diffusion coefficients has also been studied. Further, the energy loss of heavy quarks due to the elastic collisional process in an anisotropic medium has been studied. It is seen that the anisotropic contributions to heavy quark transport coefficients and its collisional energy loss have a strong dependence on the direction and strength of momentum anisotropy in the QCD medium. |
hep-ph/9603440 | GOMEZ DUMM Daniel | D. Gomez Dumm | Main phenomenological features of the spontaneous CP violation in SU(3)
x U(1) models | 21 pages RevTex, epsf, epsfig, 4 figures | Int.J.Mod.Phys. A11 (1996) 887-901 | 10.1142/S0217751X96000407 | LA PLATA - TH 95/15 | hep-ph | null | We analyze the phenomenological consequences of assuming spontaneous CP
violation in an SU(3) x U(1) model with three Higgs triplets and one sextuplet.
After the identification of the relevant physical scalars, we estimate the
contributions to the parameters $\Delta m_K$, $\epsilon$ and $\epsilon'$ coming
from the Higgs-fermion couplings.
| [
{
"created": "Fri, 29 Mar 1996 19:35:08 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Dumm",
"D. Gomez",
""
]
] | We analyze the phenomenological consequences of assuming spontaneous CP violation in an SU(3) x U(1) model with three Higgs triplets and one sextuplet. After the identification of the relevant physical scalars, we estimate the contributions to the parameters $\Delta m_K$, $\epsilon$ and $\epsilon'$ coming from the Higgs-fermion couplings. |
1804.11336 | Bithika Karmakar | Bithika Karmakar, Aritra Bandyopadhyay, Najmul Haque and Munshi G
Mustafa | General structure of gauge boson propagator and its spectra in a hot
magnetized medium | 39 pages, 7 figures | Eur. Phys. J. C (2019) 79:658 | 10.1140/epjc/s10052-019-7154-0 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based on transversality condition of gauge boson self-energy we have
systematically constructed the general structure of the gauge boson two-point
functions using four linearly independent basis tensors in presence of a
nontrivial background, i.e., hot magnetized material medium. The hard thermal
loop approximation has been used for the heat bath to compute various form
factors associated with the gauge boson's two point functions both in strong
and weak field approximation. We have also analyzed the dispersion of a gauge
boson (e.g., gluon) using the effective propagator both in strong and weak
magnetic field approximation. The formalism is also applicable to QED. The
presence of only thermal background leads to a longitudinal (plasmon) mode and
a two-fold degenerate transverse mode. In presence of a hot magnetized
background medium the degeneracy of the two transverse modes is lifted and one
gets three quasiparticle modes. In weak field approximation one gets two
transverse modes and one plasmon mode. On the other hand, in strong field
approximation also one gets the three modes in Lowest Landau Level. The general
structure of two-point function may be useful for computing the thermo-magnetic
correction of various quantities associated with a gauge boson.
| [
{
"created": "Mon, 30 Apr 2018 17:37:53 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Aug 2018 13:33:28 GMT",
"version": "v2"
},
{
"created": "Thu, 8 Aug 2019 13:32:42 GMT",
"version": "v3"
}
] | 2019-08-09 | [
[
"Karmakar",
"Bithika",
""
],
[
"Bandyopadhyay",
"Aritra",
""
],
[
"Haque",
"Najmul",
""
],
[
"Mustafa",
"Munshi G",
""
]
] | Based on transversality condition of gauge boson self-energy we have systematically constructed the general structure of the gauge boson two-point functions using four linearly independent basis tensors in presence of a nontrivial background, i.e., hot magnetized material medium. The hard thermal loop approximation has been used for the heat bath to compute various form factors associated with the gauge boson's two point functions both in strong and weak field approximation. We have also analyzed the dispersion of a gauge boson (e.g., gluon) using the effective propagator both in strong and weak magnetic field approximation. The formalism is also applicable to QED. The presence of only thermal background leads to a longitudinal (plasmon) mode and a two-fold degenerate transverse mode. In presence of a hot magnetized background medium the degeneracy of the two transverse modes is lifted and one gets three quasiparticle modes. In weak field approximation one gets two transverse modes and one plasmon mode. On the other hand, in strong field approximation also one gets the three modes in Lowest Landau Level. The general structure of two-point function may be useful for computing the thermo-magnetic correction of various quantities associated with a gauge boson. |
2407.19060 | Jo\~ao Paulo Pinheiro | Damir Be\v{c}irevi\'c, Florentin Jaffredo, Jo\~ao Paulo Pinheiro,
Olcyr Sumensari | Lepton flavor violation in exclusive $b\to d\ell_i\ell_j$ and $b\to
s\ell_i\ell_j$ decay modes | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the exclusive lepton flavor violating (LFV) decays modes based on
$b\to d\ell_i\ell_j$ and $b\to s\ell_i\ell_j$ by considering the ground state
mesons and baryons. After spelling out the expressions for such decay rates in
a low energy effective theory which includes generic contributions arising from
physics beyond the Standard Model (BSM), we show that the experimental bounds
on meson decays can be used to bound the corresponding modes involving baryons.
We find, for example, $\mathcal{B}(\Lambda_b\to \Lambda\mu\tau)\lesssim 4\times
10^{-5}$. We also consider two specific models and constrain the relevant LFV
couplings by using the low energy observables. In the first model we assume the
Higgs mediated LFV and find the resulting decay rates to be too small to be
experimentally detectable. We also emphasize that the regions favored by the
bounds $\mathcal{B}(h\to\mu\tau)^\mathrm{Atlas}$ and $\mathcal{B}(h\to
e\tau)^\mathrm{Atlas}$ are not compatible with $\mathcal{B}(\mu\to
e\gamma)^\mathrm{MEG}$ to $1\sigma$. In the second model we assume LFV mediated
by a heavy $Z'$ boson and find that the corresponding $b$-hadron branching
fractions can be $\mathcal{O}(10^{-6})$, thus possibly within experimental
reach at LHCb and Belle~II.
| [
{
"created": "Fri, 26 Jul 2024 19:37:05 GMT",
"version": "v1"
}
] | 2024-07-30 | [
[
"Bečirević",
"Damir",
""
],
[
"Jaffredo",
"Florentin",
""
],
[
"Pinheiro",
"João Paulo",
""
],
[
"Sumensari",
"Olcyr",
""
]
] | We discuss the exclusive lepton flavor violating (LFV) decays modes based on $b\to d\ell_i\ell_j$ and $b\to s\ell_i\ell_j$ by considering the ground state mesons and baryons. After spelling out the expressions for such decay rates in a low energy effective theory which includes generic contributions arising from physics beyond the Standard Model (BSM), we show that the experimental bounds on meson decays can be used to bound the corresponding modes involving baryons. We find, for example, $\mathcal{B}(\Lambda_b\to \Lambda\mu\tau)\lesssim 4\times 10^{-5}$. We also consider two specific models and constrain the relevant LFV couplings by using the low energy observables. In the first model we assume the Higgs mediated LFV and find the resulting decay rates to be too small to be experimentally detectable. We also emphasize that the regions favored by the bounds $\mathcal{B}(h\to\mu\tau)^\mathrm{Atlas}$ and $\mathcal{B}(h\to e\tau)^\mathrm{Atlas}$ are not compatible with $\mathcal{B}(\mu\to e\gamma)^\mathrm{MEG}$ to $1\sigma$. In the second model we assume LFV mediated by a heavy $Z'$ boson and find that the corresponding $b$-hadron branching fractions can be $\mathcal{O}(10^{-6})$, thus possibly within experimental reach at LHCb and Belle~II. |
hep-ph/9910250 | Willy van Neerven | A. Chuvakin, J. Smith and W.L. van Neerven | Comparison between variable flavor number schemes for charm quark
electroproduction | 64 pages, LaTeX, 16 Postscript figures | Phys.Rev.D61:096004,2000 | 10.1103/PhysRevD.61.096004 | null | hep-ph | null | Where appropriate, the abbreviation 'VFNS' is replaced by 'CSN' to indicate
the scheme using massive heavy quark coefficient functions proposed in this
paper. The text below Eq. (2.13) and between Eqs. (2.33) and (2.36) has been
considerably changed.
| [
{
"created": "Wed, 6 Oct 1999 10:05:16 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Feb 2000 10:05:48 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Chuvakin",
"A.",
""
],
[
"Smith",
"J.",
""
],
[
"van Neerven",
"W. L.",
""
]
] | Where appropriate, the abbreviation 'VFNS' is replaced by 'CSN' to indicate the scheme using massive heavy quark coefficient functions proposed in this paper. The text below Eq. (2.13) and between Eqs. (2.33) and (2.36) has been considerably changed. |
1602.03166 | Scientific Information Service CERN | Grojean, C (ed.) (CERN) Mulders, M (ed.) (CERN) | Proceedings, 2011 European School of High-Energy Physics (ESHEP 2011):
Cheile Gradistei, Romania, September 7-20, 2011 | 9 lectures, 362 pages, published as CERN Yellow Report
https://cds.cern.ch/record/1327568 | null | 10.5170/CERN-2014-003 | CERN-2014-003 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The European School of High-Energy Physics is intended to give young
physicists an introduction to the theoretical aspects of recent advances in
elementary particle physics. These proceedings contain lecture notes on quantum
field theory and the Standard Model, quantum chromodynamics, flavour physics,
neutrino physics, physics beyond the Standard Model, cosmology, heavy ion
physics, statistical data analysis, as well as an account for the physics
results with the data accumulated during the first run of the LHC.
| [
{
"created": "Tue, 15 Dec 2015 16:01:14 GMT",
"version": "v1"
}
] | 2016-02-10 | [
[
"Grojean",
"",
"",
"ed."
],
[
"C",
"",
"",
"ed."
],
[
"Mulders",
"",
"",
"ed."
],
[
"M",
"",
"",
"ed."
]
] | The European School of High-Energy Physics is intended to give young physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain lecture notes on quantum field theory and the Standard Model, quantum chromodynamics, flavour physics, neutrino physics, physics beyond the Standard Model, cosmology, heavy ion physics, statistical data analysis, as well as an account for the physics results with the data accumulated during the first run of the LHC. |
hep-ph/0412044 | V. I. Kopeikin | V. Kopeikin, L. Mikaelyan, V. Sinev | Antineutrino Background from Spent Fuel Storage in sensitive Searches
for theta_13 at Reactors | 6 pages, 3 figures, submitted to Phys. Atom. Nucl | Phys.Atom.Nucl. 69 (2006) 185-188 | 10.1134/S1063778806020025 | null | hep-ph | null | Sensitive searches for antineutrino oscillations in atmospheric mass
parameter region much discussed in recent years are based on accurate
comparison of the inverse beta decay positron spectra measured in two (or more)
detectors, far and near, stationed e.g. at ~1000 m and ~100 m from the
reactor(s). We show that antineutrinos emitted from the stored irradiated fuel
can differently distort the soft part of positron spectra measured in the far
and near detector and thus mimic (or hide) the oscillation signal
| [
{
"created": "Fri, 3 Dec 2004 09:29:46 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Kopeikin",
"V.",
""
],
[
"Mikaelyan",
"L.",
""
],
[
"Sinev",
"V.",
""
]
] | Sensitive searches for antineutrino oscillations in atmospheric mass parameter region much discussed in recent years are based on accurate comparison of the inverse beta decay positron spectra measured in two (or more) detectors, far and near, stationed e.g. at ~1000 m and ~100 m from the reactor(s). We show that antineutrinos emitted from the stored irradiated fuel can differently distort the soft part of positron spectra measured in the far and near detector and thus mimic (or hide) the oscillation signal |
hep-ph/9506376 | Verma Ramesh C. | R. C. Verma | Searching a systematics for nonfactorizable contributions to hadronic
decays of $ D^{0}$ and $ D^{+}$ mesons | 23 pages, Latex | Z.Phys. C69 (1996) 253-258 | null | Panjab Univ. May 2 - 95 | hep-ph | null | We investigate nonfactorizable contributions to charm meson decays in $ D
\rightarrow \bar K \pi $/ $ \bar K \rho$ /$ \bar K ^{*} \pi$ / $ \bar K a_{1}$
/ $ \bar K ^{*} \rho $ modes. Obtaining the contributions from spectator-quark
diagrams for $ N_{c}$ = 3, we determine nonfactorizable isospin 1/2 and 3/2
amplitudes required to explain the data for these modes. We observe that ratio
of these amplitudes seem to follow a universal value.
| [
{
"created": "Tue, 20 Jun 1995 14:53:18 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Verma",
"R. C.",
""
]
] | We investigate nonfactorizable contributions to charm meson decays in $ D \rightarrow \bar K \pi $/ $ \bar K \rho$ /$ \bar K ^{*} \pi$ / $ \bar K a_{1}$ / $ \bar K ^{*} \rho $ modes. Obtaining the contributions from spectator-quark diagrams for $ N_{c}$ = 3, we determine nonfactorizable isospin 1/2 and 3/2 amplitudes required to explain the data for these modes. We observe that ratio of these amplitudes seem to follow a universal value. |
2203.01734 | Kechen Wang | Filmon Andom Ghebretinsaea, Zeren Simon Wang and Kechen Wang | Probing axion-like particles coupling to gluons at the LHC | 24 pages, 10 figures, 3 tables | https://link.springer.com/article/10.1007/JHEP07(2022)070 | 10.1007/JHEP07(2022)070 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Assuming ALPs couple to gluons only, they can be produced via the $p p \to a
j$ process and decay into two jets at the LHC. When the coupling parameter,
$C_{\tilde{G}} / f_a$, is small, the lifetime of ALPs can be long enough
leading to displaced final state jets. In this paper, we consider the signal
including both the prompt and long-lived cases of ALPs by employing a
specialized Delphes module to handle displaced jets. Relevant background
processes are generated and simulated at the detector level, and multivariate
analyses based on machine-learning are performed to discriminate signal and
background events and achieve the best sensitivities. Based on the data
accumulated for this study, we forecast the expected upper limits on
$C_{\tilde{G}}/f_a$ for ALP mass $m_a$ in the range 5$-$2300 GeV at 2-, 3- and
5-$\sigma$ significances at the High Luminosity-LHC with 14 TeV center-of-mass
energy and 3 ab$^{-1}$ integrated luminosity. Vast previously unprobed regions
in the parameter space spanned by $C_{\tilde{G}}/f_a$ and $m_a$ are probed and
the best upper limits on $C_{\tilde{G}}/f_a$ at 2-$\sigma$ significance is
found to be around $1.0 \times 10^{-2} \,\, {\rm TeV^{-1}}$ for $m_a \sim 500$
GeV. The ALP mass is reconstructed from the kinematics of final state jets and
we find that it is measurable in this method when $m_a$ is below about 1 TeV at
the HL-LHC. The effects of systematic uncertainties and validation of the EFT
framework are also checked and discussed.
| [
{
"created": "Thu, 3 Mar 2022 14:25:39 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jul 2022 07:13:42 GMT",
"version": "v2"
}
] | 2022-08-01 | [
[
"Ghebretinsaea",
"Filmon Andom",
""
],
[
"Wang",
"Zeren Simon",
""
],
[
"Wang",
"Kechen",
""
]
] | Assuming ALPs couple to gluons only, they can be produced via the $p p \to a j$ process and decay into two jets at the LHC. When the coupling parameter, $C_{\tilde{G}} / f_a$, is small, the lifetime of ALPs can be long enough leading to displaced final state jets. In this paper, we consider the signal including both the prompt and long-lived cases of ALPs by employing a specialized Delphes module to handle displaced jets. Relevant background processes are generated and simulated at the detector level, and multivariate analyses based on machine-learning are performed to discriminate signal and background events and achieve the best sensitivities. Based on the data accumulated for this study, we forecast the expected upper limits on $C_{\tilde{G}}/f_a$ for ALP mass $m_a$ in the range 5$-$2300 GeV at 2-, 3- and 5-$\sigma$ significances at the High Luminosity-LHC with 14 TeV center-of-mass energy and 3 ab$^{-1}$ integrated luminosity. Vast previously unprobed regions in the parameter space spanned by $C_{\tilde{G}}/f_a$ and $m_a$ are probed and the best upper limits on $C_{\tilde{G}}/f_a$ at 2-$\sigma$ significance is found to be around $1.0 \times 10^{-2} \,\, {\rm TeV^{-1}}$ for $m_a \sim 500$ GeV. The ALP mass is reconstructed from the kinematics of final state jets and we find that it is measurable in this method when $m_a$ is below about 1 TeV at the HL-LHC. The effects of systematic uncertainties and validation of the EFT framework are also checked and discussed. |
2405.12677 | Sami Yrj\"anheikki | Ilkka Helenius, Hannu Paukkunen, Sami Yrj\"anheikki | Dimuons from neutrino-nucleus collisions in the semi-inclusive DIS
approach | null | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We present a next-to-leading order perturbative QCD calculation of dimuon
production in neutrino-nucleus collisions. This process is typically calculated
by assuming it to be proportional to inclusive charm production, which requires
an effective acceptance correction to take the experimental cuts on the
decay-muon kinematics into account. Here, we instead compute the dimuon
production cross section directly as a convolution of semi-inclusive deep
inelastic scattering to produce charmed hadrons, and a decay function fitted to
$e^+e^-$ data to produce a muon from the charmed hadrons. The presented
approach is in a good agreement with available experimental data and will serve
as a starting point for higher-order QCD calculations without an external
acceptance correction. The uncertainties arising from the decay function and
scale dependence are sizeably smaller than those from the nuclear parton
distribution functions. We also calculate the effective acceptances within our
approach and compare them to those usually used in global fits of parton
distribution functions, finding differences of the order of $10\,\%$, depending
on the kinematics, perturbative order, and applied parton distributions.
| [
{
"created": "Tue, 21 May 2024 11:10:41 GMT",
"version": "v1"
}
] | 2024-05-22 | [
[
"Helenius",
"Ilkka",
""
],
[
"Paukkunen",
"Hannu",
""
],
[
"Yrjänheikki",
"Sami",
""
]
] | We present a next-to-leading order perturbative QCD calculation of dimuon production in neutrino-nucleus collisions. This process is typically calculated by assuming it to be proportional to inclusive charm production, which requires an effective acceptance correction to take the experimental cuts on the decay-muon kinematics into account. Here, we instead compute the dimuon production cross section directly as a convolution of semi-inclusive deep inelastic scattering to produce charmed hadrons, and a decay function fitted to $e^+e^-$ data to produce a muon from the charmed hadrons. The presented approach is in a good agreement with available experimental data and will serve as a starting point for higher-order QCD calculations without an external acceptance correction. The uncertainties arising from the decay function and scale dependence are sizeably smaller than those from the nuclear parton distribution functions. We also calculate the effective acceptances within our approach and compare them to those usually used in global fits of parton distribution functions, finding differences of the order of $10\,\%$, depending on the kinematics, perturbative order, and applied parton distributions. |
2403.18029 | Alexander Ilyichev Dr. | Igor Akushevich, Alexander Ilyichev, Stanislav Srednyak | Exact and Leading Order Radiative Effects in Semi-inclusive Deep
Inelastic Scattering | 18 pages, 7 figure | Phys. Rev. D 109, 076028 (2024) | 10.1103/PhysRevD.109.076028 | JLAB-PHY-23-3785 | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | Radiative effects in semi-inclusive hadron leptoproduction of unpolarized
particles are calculated within the leading order approximation. The
contributions of the infrared-free sum of the effects of real and virtual
photon emission as well as the contribution of exclusive radiative tail are
considered. It is demonstrated how the obtained formulae in the leading log
approximation can be obtained using the standard approach of the leading log
approximation as well as from the exact expressions for the radiative
correction of the lowest order. The method of the electron structure function
is used to calculate the higher order corrections. The results are analytically
compared to the results obtained by other groups. Numeric illustrations are
given in the kinematics of the modern experiments at Jefferson Laboratory.
| [
{
"created": "Tue, 26 Mar 2024 18:31:31 GMT",
"version": "v1"
}
] | 2024-04-30 | [
[
"Akushevich",
"Igor",
""
],
[
"Ilyichev",
"Alexander",
""
],
[
"Srednyak",
"Stanislav",
""
]
] | Radiative effects in semi-inclusive hadron leptoproduction of unpolarized particles are calculated within the leading order approximation. The contributions of the infrared-free sum of the effects of real and virtual photon emission as well as the contribution of exclusive radiative tail are considered. It is demonstrated how the obtained formulae in the leading log approximation can be obtained using the standard approach of the leading log approximation as well as from the exact expressions for the radiative correction of the lowest order. The method of the electron structure function is used to calculate the higher order corrections. The results are analytically compared to the results obtained by other groups. Numeric illustrations are given in the kinematics of the modern experiments at Jefferson Laboratory. |
hep-ph/0101188 | Ayse Kizilersu | A.Kizilersu, T.Sizer and A.G.Williams | Regularization-independent study of renormalized non-perturbative
quenched QED | 20 pages,5 figures | Phys.Rev.D65:085020,2002 | 10.1103/PhysRevD.65.085020 | null | hep-ph hep-th | null | A recently proposed regularization-independent method is used for the first
time to solve the renormalized fermion Schwinger-Dyson equation numerically in
quenched QED$_4$. The Curtis-Pennington vertex is used to illustrate the
technique and to facilitate comparison with previous calculations which used
the alternative regularization schemes of modified ultraviolet cut-off and
dimensional regularization. Our new results are in excellent numerical
agreement with these, and so we can now conclude with confidence that there is
no residual regularization dependence in these results. Moreover, from a
computational point of view the regularization independent method has enormous
advantages, since all integrals are absolutely convergent by construction, and
so do not mix small and arbitrarily large momentum scales. We analytically
predict power law behaviour in the asymptotic region, which is confirmed
numerically with high precision. The successful demonstration of this efficient
new technique opens the way for studies of unquenched QED to be undertaken in
the near future.
| [
{
"created": "Wed, 17 Jan 2001 01:43:16 GMT",
"version": "v1"
}
] | 2010-03-04 | [
[
"Kizilersu",
"A.",
""
],
[
"Sizer",
"T.",
""
],
[
"Williams",
"A. G.",
""
]
] | A recently proposed regularization-independent method is used for the first time to solve the renormalized fermion Schwinger-Dyson equation numerically in quenched QED$_4$. The Curtis-Pennington vertex is used to illustrate the technique and to facilitate comparison with previous calculations which used the alternative regularization schemes of modified ultraviolet cut-off and dimensional regularization. Our new results are in excellent numerical agreement with these, and so we can now conclude with confidence that there is no residual regularization dependence in these results. Moreover, from a computational point of view the regularization independent method has enormous advantages, since all integrals are absolutely convergent by construction, and so do not mix small and arbitrarily large momentum scales. We analytically predict power law behaviour in the asymptotic region, which is confirmed numerically with high precision. The successful demonstration of this efficient new technique opens the way for studies of unquenched QED to be undertaken in the near future. |
0811.0956 | Peihong Gu | Pei-Hong Gu, Utpal Sarkar | Pathways to testable leptogenesis | 4 pages, 3 figures | Mod.Phys.Lett.A25:501-509,2010 | 10.1142/S0217732310032597 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the conventional seesaw models of neutrino masses, leptogenesis occurs at
a very high scale. Three approaches have been discussed in the literature to
lower the scale of leptogenesis: mass degeneracy, hierarchy of couplings and
three-body decays. We advocate yet another approach to a testable leptogenesis,
whereby the decaying particles could go out of equilibrium at an accessible
scale due to kinematics, although their couplings to the decay products are
larger for generating a desired CP asymmetry. We demonstrate this new
possibility for the testable leptogenesis in a two Higgs doublet model where
the neutrino masses originate from a one-loop diagram.
| [
{
"created": "Thu, 6 Nov 2008 14:23:50 GMT",
"version": "v1"
}
] | 2010-11-15 | [
[
"Gu",
"Pei-Hong",
""
],
[
"Sarkar",
"Utpal",
""
]
] | In the conventional seesaw models of neutrino masses, leptogenesis occurs at a very high scale. Three approaches have been discussed in the literature to lower the scale of leptogenesis: mass degeneracy, hierarchy of couplings and three-body decays. We advocate yet another approach to a testable leptogenesis, whereby the decaying particles could go out of equilibrium at an accessible scale due to kinematics, although their couplings to the decay products are larger for generating a desired CP asymmetry. We demonstrate this new possibility for the testable leptogenesis in a two Higgs doublet model where the neutrino masses originate from a one-loop diagram. |
1001.1281 | S. Weinzierl | Stefan Weinzierl | NNLO predictions for event shapes and jet rates in electron-positron
annihilation | 6 pages, talk given at RADCOR 2009 | PoS RADCOR2009:051,2010 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The strong coupling constant is a fundamental parameter of nature. It can be
extracted from experiments measuring three-jet events in electron-positron
annihilation. For this extraction precise theoretical calculations for jet
rates and event shapes are needed. In this talk I will discuss the NNLO
calculation for these observables.
| [
{
"created": "Fri, 8 Jan 2010 14:12:57 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Weinzierl",
"Stefan",
""
]
] | The strong coupling constant is a fundamental parameter of nature. It can be extracted from experiments measuring three-jet events in electron-positron annihilation. For this extraction precise theoretical calculations for jet rates and event shapes are needed. In this talk I will discuss the NNLO calculation for these observables. |
1711.06380 | Istv\'an Szanyi | Norbert Bence, L\'aszl\'o Jenkovszky and Istv\'an Szanyi | Approaching the asymptotics at the LHC | 16 pages, 8 figures; submitted to Physical Review D | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent results on the slope of the $pp$ diffraction cone measured by TOTEM at
$7$ and $8$ GeV show an unexpected rapid rise in $s$, close to $B(s)\sim
\ln^2$, rather than $\ln s$, typical of the Regge-pole predictions. We show
that the new phenomenon can be accommodated by the inclusion of unitarity
corrections to a simple Regge (pomeron) pole exchange. Interestingly, the
odderon may also promote the acceleration of $B(s)$. The onset of the new
regime may be indicative of the approach to the asymptotic dynamics of strong
interactions. We analyse the new data together with other available forward
measurable in a unitarized Regge dipole. Unitarization proves crucial in
fitting the data, especially those on the slope $B(s)$ showing a change from
the $\ln (s)$ to $\ln^2 (s)$ behavior. Having fitted the free parameters of the
unitarized model to the data, we predict the behavior of the cross sections and
the slope at still higher energies, including those asymptotic.
| [
{
"created": "Fri, 17 Nov 2017 02:28:38 GMT",
"version": "v1"
}
] | 2017-11-20 | [
[
"Bence",
"Norbert",
""
],
[
"Jenkovszky",
"László",
""
],
[
"Szanyi",
"István",
""
]
] | Recent results on the slope of the $pp$ diffraction cone measured by TOTEM at $7$ and $8$ GeV show an unexpected rapid rise in $s$, close to $B(s)\sim \ln^2$, rather than $\ln s$, typical of the Regge-pole predictions. We show that the new phenomenon can be accommodated by the inclusion of unitarity corrections to a simple Regge (pomeron) pole exchange. Interestingly, the odderon may also promote the acceleration of $B(s)$. The onset of the new regime may be indicative of the approach to the asymptotic dynamics of strong interactions. We analyse the new data together with other available forward measurable in a unitarized Regge dipole. Unitarization proves crucial in fitting the data, especially those on the slope $B(s)$ showing a change from the $\ln (s)$ to $\ln^2 (s)$ behavior. Having fitted the free parameters of the unitarized model to the data, we predict the behavior of the cross sections and the slope at still higher energies, including those asymptotic. |
1312.3377 | David Kapukchyan | David Kapukchyan, Tim M.P. Tait | Sensitivity of a Future High Energy $e^+ e^-$ Collider to $Z^\prime$
Bosons | null | null | 10.1088/0954-3899/41/7/075011 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the capability of a future high energy $e^+ e^-$ collider to
search for the $Z^\prime$ bosons associated with a $U(1)^\prime$ gauge
extension of the Standard Model. Even for $Z^\prime$ masses well above the
center of mass energy of the collider, the rates of production of $e^+ e^-$,
$\mu^+ \mu^-$, unflavored jets, and $b$-tagged jets can reveal the presence of
virtual $Z^\prime$ exchange. We consider collider configurations with
center-of-mass energy 200, 300, and 500 GeV, and show how various classes of
$Z^\prime$ model-lines can be probed with $100~{\rm fb}^{-1}$ of integrated
luminosity. We find that for order one couplings, $Z^\prime$ masses on the
order of several TeV can be discovered, depending on the collider energy. Our
results suggest that a 200 GeV collision energy is unlikely to discover any of
the $Z^\prime$ models we consider that would not have already been visible in
late stages of LHC running, but could still help refine understanding of the
couplings and distinguish between different models. For $e^+ e^-$ collision
energies of 300 GeV, parameter space beyond the reach of the LHC becomes
accessible.
| [
{
"created": "Thu, 12 Dec 2013 00:48:33 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Jun 2014 02:49:46 GMT",
"version": "v2"
}
] | 2015-06-18 | [
[
"Kapukchyan",
"David",
""
],
[
"Tait",
"Tim M. P.",
""
]
] | We consider the capability of a future high energy $e^+ e^-$ collider to search for the $Z^\prime$ bosons associated with a $U(1)^\prime$ gauge extension of the Standard Model. Even for $Z^\prime$ masses well above the center of mass energy of the collider, the rates of production of $e^+ e^-$, $\mu^+ \mu^-$, unflavored jets, and $b$-tagged jets can reveal the presence of virtual $Z^\prime$ exchange. We consider collider configurations with center-of-mass energy 200, 300, and 500 GeV, and show how various classes of $Z^\prime$ model-lines can be probed with $100~{\rm fb}^{-1}$ of integrated luminosity. We find that for order one couplings, $Z^\prime$ masses on the order of several TeV can be discovered, depending on the collider energy. Our results suggest that a 200 GeV collision energy is unlikely to discover any of the $Z^\prime$ models we consider that would not have already been visible in late stages of LHC running, but could still help refine understanding of the couplings and distinguish between different models. For $e^+ e^-$ collision energies of 300 GeV, parameter space beyond the reach of the LHC becomes accessible. |
2103.05257 | Qi Wu | Qi Wu, Dian-Yong Chen, Ran Ji | Production of $P_{cs}(4459)$ from $\Xi_b$ decay | 6 pages,2 figures, 1 table; matches published version | Chin. Phys. Lett. 38, 071301 (2021) | 10.1088/0256-307X/38/7/071301 | null | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | Inspired by the $P_{cs}(4459)$ reported by the LHCb collaboration recently,
we investigate the $P_{cs}(4459)$ production from $\Xi_b$ decay in a molecular
scenario using an effective Lagrangian approach. With different $J^P$
assignments to $P_{cs}(4459)$, the magnitude of branching fractions of $\Xi_b
\to P_{cs}(4459) K$ is estimated, which is of the order of $10^{-4}$. Together
with the decay properties of $P_{cs}(4459)$, the present estimations could be
further testified by precise measurements and contribute to a better
understanding of the molecular interpretations and the exploration of $J^P$
quantum numbers of $P_{cs}(4459)$.
| [
{
"created": "Tue, 9 Mar 2021 07:03:07 GMT",
"version": "v1"
},
{
"created": "Sat, 10 Jul 2021 04:21:35 GMT",
"version": "v2"
}
] | 2021-09-01 | [
[
"Wu",
"Qi",
""
],
[
"Chen",
"Dian-Yong",
""
],
[
"Ji",
"Ran",
""
]
] | Inspired by the $P_{cs}(4459)$ reported by the LHCb collaboration recently, we investigate the $P_{cs}(4459)$ production from $\Xi_b$ decay in a molecular scenario using an effective Lagrangian approach. With different $J^P$ assignments to $P_{cs}(4459)$, the magnitude of branching fractions of $\Xi_b \to P_{cs}(4459) K$ is estimated, which is of the order of $10^{-4}$. Together with the decay properties of $P_{cs}(4459)$, the present estimations could be further testified by precise measurements and contribute to a better understanding of the molecular interpretations and the exploration of $J^P$ quantum numbers of $P_{cs}(4459)$. |
hep-ph/0408235 | Bo-Qiang Ma | Nan Li, Bo-Qiang Ma | A New Parametrization of the Neutrino Mixing Matrix | 11 pages, 4 figures, version published in PLB | Phys.Lett.B600:248-254,2004 | 10.1016/j.physletb.2004.08.069 | null | hep-ph astro-ph hep-ex nucl-ex nucl-th | null | The neutrino mixing matrix is expanded in powers of a small parameter
$\lambda$, which approximately equals to 0.1. The meaning of every order of the
expansion is discussed respectively, and the range of $\lambda$ is carefully
calculated. We also present some applications of this new parametrization, such
as to the expression of the Jarlskog parameter $J$, in which the simplicities
and advantages of this parametrization are shown.
| [
{
"created": "Sun, 22 Aug 2004 04:04:39 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Dec 2004 16:41:19 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Li",
"Nan",
""
],
[
"Ma",
"Bo-Qiang",
""
]
] | The neutrino mixing matrix is expanded in powers of a small parameter $\lambda$, which approximately equals to 0.1. The meaning of every order of the expansion is discussed respectively, and the range of $\lambda$ is carefully calculated. We also present some applications of this new parametrization, such as to the expression of the Jarlskog parameter $J$, in which the simplicities and advantages of this parametrization are shown. |
2002.05008 | Vladimir Skalozub | O. A. Borisenko and V. V. Skalozub | On plasmon contribution to the hot A_0 condensate | 5 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In SU(2) gluodynamics, the Debye gluon contribution W_D(A_0) to the effective
action of the temporal gauge field component, A_0 = const, at high temperature
is calculated in the background R^{xi} gauge. It is shown that at nonzero A_0
the standard definition k_0 = 0, |k| -> 0 corresponds to long distance
correlations for the longitudinal in internal space gluons. The transversal
gluons become screened by the A_0 background field. Therefore they give zero
contributions and have to be excluded from the correlation corrections. The
total effective action accounting for the one-loop, two-loop and correct
W_D(A_0) satisfies Nielsen's identity that proves gauge invariance of the A_0
condensation phenomenon.
| [
{
"created": "Wed, 12 Feb 2020 14:13:42 GMT",
"version": "v1"
}
] | 2020-02-13 | [
[
"Borisenko",
"O. A.",
""
],
[
"Skalozub",
"V. V.",
""
]
] | In SU(2) gluodynamics, the Debye gluon contribution W_D(A_0) to the effective action of the temporal gauge field component, A_0 = const, at high temperature is calculated in the background R^{xi} gauge. It is shown that at nonzero A_0 the standard definition k_0 = 0, |k| -> 0 corresponds to long distance correlations for the longitudinal in internal space gluons. The transversal gluons become screened by the A_0 background field. Therefore they give zero contributions and have to be excluded from the correlation corrections. The total effective action accounting for the one-loop, two-loop and correct W_D(A_0) satisfies Nielsen's identity that proves gauge invariance of the A_0 condensation phenomenon. |
hep-ph/0110217 | Bertrand Laforge | C. Balazs, B. Laforge | Probing TeV-scale gauge unification by hadronic collisions | 10 pages, 2 figures, using JHEP style | Phys.Lett. B525 (2002) 219-224 | 10.1016/S0370-2693(01)01466-6 | LPNHE 2001-06, UH-511-991-01 | hep-ph | null | Grand unified theories (GUTs) and extra dimensions are potential ingredients
of the new physics that may resolve various outstanding problems of the
Standard Model. If the inverse size of (one of) the extra dimension(s) is
smaller than the GUT scale and standard gauge bosons are allowed to propagate
in the bulk then, among other consequences, the evolution of the gauge
couplings deviates from the usual logarithmic running somewhat below and
between these two scales.
In this work, we show that if the compactification scale is the order of 10
TeV, then this modified running may be observable at the CERN Large Hadron
Collider in the dijet invariant mass distribution. We also demonstrate that
dijets are highly sensitive to the renormalization effects of the extra
dimensions, and are potential tools for determining the number of dimensions
and the value of the compactification scale.
| [
{
"created": "Tue, 16 Oct 2001 16:05:39 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Balazs",
"C.",
""
],
[
"Laforge",
"B.",
""
]
] | Grand unified theories (GUTs) and extra dimensions are potential ingredients of the new physics that may resolve various outstanding problems of the Standard Model. If the inverse size of (one of) the extra dimension(s) is smaller than the GUT scale and standard gauge bosons are allowed to propagate in the bulk then, among other consequences, the evolution of the gauge couplings deviates from the usual logarithmic running somewhat below and between these two scales. In this work, we show that if the compactification scale is the order of 10 TeV, then this modified running may be observable at the CERN Large Hadron Collider in the dijet invariant mass distribution. We also demonstrate that dijets are highly sensitive to the renormalization effects of the extra dimensions, and are potential tools for determining the number of dimensions and the value of the compactification scale. |
1903.02570 | Qin Qin | Jian-Nan Ding, Qin Qin and Fu-Sheng Yu | Heavy neutrino searches at future $Z$-factories | 17 pages, 6 figures, more complete SM background is considered
compared to v1 | null | 10.1140/epjc/s10052-019-7277-3 | SI-HEP-2019-02, QFET-2019-02 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the capacity of future $Z$-factories to search for heavy neutrinos
with their mass from 10 to 85 GeV. The heavy neutrinos $N$ are considered to be
produced via the process $e^+e^-\to Z\to \nu N$ and to decay into an electron
or muon and two jets. By means of Monte Carlo simulation of such signal events
and the Standard Model background events, we obtain the upper bounds on the
cross sections $\sigma(e^+e^-\to \nu N\to \nu\ell jj)$ given by the
$Z$-factories with integrated luminosities of 0.1, 1 and 10 ab$^{-1}$ if no
signal events are observed. Under the assumption of a minimal extension of the
Standard Model in the neutrino sector, we also present the corresponding
constraints on the mixing parameters of the heavy neutrinos with the Standard
Model leptons, and find they are improved by at least one order compared to
current experimental constraints.
| [
{
"created": "Wed, 6 Mar 2019 19:00:05 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Sep 2019 04:05:47 GMT",
"version": "v2"
}
] | 2019-09-20 | [
[
"Ding",
"Jian-Nan",
""
],
[
"Qin",
"Qin",
""
],
[
"Yu",
"Fu-Sheng",
""
]
] | We analyze the capacity of future $Z$-factories to search for heavy neutrinos with their mass from 10 to 85 GeV. The heavy neutrinos $N$ are considered to be produced via the process $e^+e^-\to Z\to \nu N$ and to decay into an electron or muon and two jets. By means of Monte Carlo simulation of such signal events and the Standard Model background events, we obtain the upper bounds on the cross sections $\sigma(e^+e^-\to \nu N\to \nu\ell jj)$ given by the $Z$-factories with integrated luminosities of 0.1, 1 and 10 ab$^{-1}$ if no signal events are observed. Under the assumption of a minimal extension of the Standard Model in the neutrino sector, we also present the corresponding constraints on the mixing parameters of the heavy neutrinos with the Standard Model leptons, and find they are improved by at least one order compared to current experimental constraints. |
1906.02523 | Alexandru Catalin Ene Mr. | Alexandru Catalin Ene, Alexandru Jipa, Lavinia-Elena Giubega | Study of Monte Carlo event generators for proton-proton collisions at
LHC energies in the forward region | null | null | 10.1088/1674-1137/43/8/083001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we present a comparative study between PYTHIA, EPOS, QGSJET,
and SIBYLL generators. The global event observables considered are the charged
energy flow, charged-particle distributions, charged-hadron production ratios
and $V^{0}$ ratios. The study is performed in the LHCb and TOTEM fiducial
phase-spaces on minimum bias simulated data samples for \emph{pp} collisions at
$\sqrt{s} = 7$ TeV using reference measurements from the aforementioned
experiments. In the majority of cases, the measurements are within a band
defined by the most extreme predictions. The observed differences between the
predictions and the measurements seem to be, in most part, caused by
extrapolation from the central pseudorapidity region ($|\eta| \leq$ 2.5), in
which the generators were mainly tuned.
| [
{
"created": "Thu, 6 Jun 2019 11:23:18 GMT",
"version": "v1"
}
] | 2019-09-04 | [
[
"Ene",
"Alexandru Catalin",
""
],
[
"Jipa",
"Alexandru",
""
],
[
"Giubega",
"Lavinia-Elena",
""
]
] | In this paper we present a comparative study between PYTHIA, EPOS, QGSJET, and SIBYLL generators. The global event observables considered are the charged energy flow, charged-particle distributions, charged-hadron production ratios and $V^{0}$ ratios. The study is performed in the LHCb and TOTEM fiducial phase-spaces on minimum bias simulated data samples for \emph{pp} collisions at $\sqrt{s} = 7$ TeV using reference measurements from the aforementioned experiments. In the majority of cases, the measurements are within a band defined by the most extreme predictions. The observed differences between the predictions and the measurements seem to be, in most part, caused by extrapolation from the central pseudorapidity region ($|\eta| \leq$ 2.5), in which the generators were mainly tuned. |
2401.02781 | Jun Gao | Jun Gao, ChongYang Liu, XiaoMin Shen, Hongxi Xing, Yuxiang Zhao | Simultaneous Determination of Fragmentation Functions and Test on
Momentum Sum Rule | published version; link to FF grids provided | Phys.Rev.Lett. 132 (2024) 26, 261903 | 10.1103/PhysRevLett.132.261903 | null | hep-ph hep-ex nucl-th | http://creativecommons.org/publicdomain/zero/1.0/ | We perform a simultaneous global analysis of hadron fragmentation functions
(FFs) to various charged hadrons at next-to-leading order in QCD. The world
data set includes results from electron-positron single-inclusive annihilation,
semi-inclusive deep inelastic scattering, as well as proton-proton collisions
including jet fragmentation measurements which lead to strong constraints on
the gluon fragmentations. By carefully selecting hadron kinematics to ensure
the validity of QCD factorization and the convergence of perturbative
calculations, we achieve a satisfying best fit with $\chi^2/$d.o.f.$=0.90$, in
the simultaneous extraction of FFs for light charged hadrons ($\pi^{\pm}$,
$K^{\pm}$ and $p/\bar{p}$). The total momentum of $u$, $d$ quarks and gluon
carried by light charged hadrons have been determined precisely. That urges
future precision measurements on fragmentation to neutral hadrons, which are
crucial for the test of fundamental sum rules in QCD fragmentation.
| [
{
"created": "Fri, 5 Jan 2024 12:41:17 GMT",
"version": "v1"
},
{
"created": "Sat, 29 Jun 2024 13:12:43 GMT",
"version": "v2"
}
] | 2024-07-02 | [
[
"Gao",
"Jun",
""
],
[
"Liu",
"ChongYang",
""
],
[
"Shen",
"XiaoMin",
""
],
[
"Xing",
"Hongxi",
""
],
[
"Zhao",
"Yuxiang",
""
]
] | We perform a simultaneous global analysis of hadron fragmentation functions (FFs) to various charged hadrons at next-to-leading order in QCD. The world data set includes results from electron-positron single-inclusive annihilation, semi-inclusive deep inelastic scattering, as well as proton-proton collisions including jet fragmentation measurements which lead to strong constraints on the gluon fragmentations. By carefully selecting hadron kinematics to ensure the validity of QCD factorization and the convergence of perturbative calculations, we achieve a satisfying best fit with $\chi^2/$d.o.f.$=0.90$, in the simultaneous extraction of FFs for light charged hadrons ($\pi^{\pm}$, $K^{\pm}$ and $p/\bar{p}$). The total momentum of $u$, $d$ quarks and gluon carried by light charged hadrons have been determined precisely. That urges future precision measurements on fragmentation to neutral hadrons, which are crucial for the test of fundamental sum rules in QCD fragmentation. |
hep-ph/0011046 | Soon-Tae Hong | Soon-Tae Hong, Young-Jai Park | Flavor symmetry breaking effects on SU(3) Skyrmion | 12 pages, latex, no figures | Phys.Rev. D63 (2001) 054018 | 10.1103/PhysRevD.63.054018 | SOGANG-HEP 275/00 | hep-ph | null | We study the massive SU(3) Skyrmion model to investigate the flavor symmetry
breaking (FSB) effects on the static properties of the strange baryons in the
framework of the rigid rotator quantization scheme combined with the improved
Dirac quantization one. Both the chiral symmetry breaking pion mass and FSB
kinetic terms are shown to improve $c$ the ratio of the strange-light to
light-light interaction strengths and $\bar{c}$ that of the strange-strange to
light-light.
| [
{
"created": "Fri, 3 Nov 2000 02:52:08 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Hong",
"Soon-Tae",
""
],
[
"Park",
"Young-Jai",
""
]
] | We study the massive SU(3) Skyrmion model to investigate the flavor symmetry breaking (FSB) effects on the static properties of the strange baryons in the framework of the rigid rotator quantization scheme combined with the improved Dirac quantization one. Both the chiral symmetry breaking pion mass and FSB kinetic terms are shown to improve $c$ the ratio of the strange-light to light-light interaction strengths and $\bar{c}$ that of the strange-strange to light-light. |
1309.0780 | Rui-Lin Zhu | Ruilin Zhu, Peng Sun, Feng Yuan | Low Transverse Momentum Heavy Quark Pair Production to Probe Gluon
Tomography | 9 pages, 2 figures | null | 10.1016/j.physletb.2013.11.002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive the transverse momentum dependent (TMD) factorization for heavy
quark pair production in deep inelastic scattering, where the total transverse
momentum is much smaller than the invariant mass of the pair. The factorization
is demonstrated at one-loop order, in both Ji-Ma-Yuan and Collins-11 schemes
for the TMD definitions, and the hard factors are calculated accordingly. Our
result provides a solid theoretical foundation for the phenomenological
investigations of the gluon TMDs in this process, and can be extended to other
similar hard processes, including dijet (di-hadron) production in DIS.
| [
{
"created": "Tue, 3 Sep 2013 19:08:38 GMT",
"version": "v1"
}
] | 2015-06-17 | [
[
"Zhu",
"Ruilin",
""
],
[
"Sun",
"Peng",
""
],
[
"Yuan",
"Feng",
""
]
] | We derive the transverse momentum dependent (TMD) factorization for heavy quark pair production in deep inelastic scattering, where the total transverse momentum is much smaller than the invariant mass of the pair. The factorization is demonstrated at one-loop order, in both Ji-Ma-Yuan and Collins-11 schemes for the TMD definitions, and the hard factors are calculated accordingly. Our result provides a solid theoretical foundation for the phenomenological investigations of the gluon TMDs in this process, and can be extended to other similar hard processes, including dijet (di-hadron) production in DIS. |
hep-ph/9404239 | Jose Ramon Pelaez | A.Dobado, J.R.Pelaez (Departamento de Fisica Teorica, Universidad
Complutense de Madrid) | The Equivalence Theorem for Chiral Lagrangians | 18 pages, LaTeX, FT/UCM/2/94 (We have corrected some errata) | Phys.Lett.B329:469-478,1994; Addendum-ibid.B335:554,1994 | 10.1016/0370-2693(94)91092-8 | null | hep-ph | null | In this work we derive the version of the Equivalence Theorem that applies
when the symmetry breaking sector of the Standard Model is described by a
general chiral lagrangian. The demonstration is valid for renormalized fields
for any value of the gauge parameter (in $R_{\xi}$ gauges) and any
parametrization of the coset space. It is based in the absence of gauge
anomalies which makes it possible to build an (anti)-BRS invariant chiral
lagrangian in terms of the renormalized fields and therefore to use the
corresponding Ward identities to obtain the theorem.
| [
{
"created": "Fri, 8 Apr 1994 17:06:50 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Apr 1994 12:53:54 GMT",
"version": "v2"
}
] | 2019-08-17 | [
[
"Dobado",
"A.",
"",
"Departamento de Fisica Teorica, Universidad\n Complutense de Madrid"
],
[
"Pelaez",
"J. R.",
"",
"Departamento de Fisica Teorica, Universidad\n Complutense de Madrid"
]
] | In this work we derive the version of the Equivalence Theorem that applies when the symmetry breaking sector of the Standard Model is described by a general chiral lagrangian. The demonstration is valid for renormalized fields for any value of the gauge parameter (in $R_{\xi}$ gauges) and any parametrization of the coset space. It is based in the absence of gauge anomalies which makes it possible to build an (anti)-BRS invariant chiral lagrangian in terms of the renormalized fields and therefore to use the corresponding Ward identities to obtain the theorem. |
2007.00565 | Andreas Helset | Chris Hays, Andreas Helset, Adam Martin, Michael Trott | Exact SMEFT formulation and expansion to $\mathcal{O}(v^4/\Lambda^4)$ | 42 pages, 9 figures | null | 10.1007/JHEP11(2020)087 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Standard Model Effective Field Theory (SMEFT) theoretical framework is
increasingly used to interpret particle physics measurements and constrain
physics beyond the Standard Model. We investigate the truncation of the
effective-operator expansion using the geometric formulation of the SMEFT,
which allows exact solutions, up to mass-dimension eight. Using this
construction, we compare the exact solution to the expansion at
${\mathcal{O}}(v^2/\Lambda^2)$, partial ${\mathcal{O}}(v^4/\Lambda^4)$ using a
subset of terms with dimension-6 operators, and full
${\mathcal{O}}(v^4/\Lambda^4)$, where $v$ is the vacuum expectation value and
$\Lambda$ is the scale of new physics. This comparison is performed for general
values of the coefficients, and for the specific model of a heavy U(1) gauge
field kinetically mixed with the Standard Model. We additionally determine the
input-parameter scheme dependence at all orders in $v/\Lambda$, and show that
this dependence increases at higher orders in $v/\Lambda$.
| [
{
"created": "Wed, 1 Jul 2020 15:51:52 GMT",
"version": "v1"
}
] | 2020-12-02 | [
[
"Hays",
"Chris",
""
],
[
"Helset",
"Andreas",
""
],
[
"Martin",
"Adam",
""
],
[
"Trott",
"Michael",
""
]
] | The Standard Model Effective Field Theory (SMEFT) theoretical framework is increasingly used to interpret particle physics measurements and constrain physics beyond the Standard Model. We investigate the truncation of the effective-operator expansion using the geometric formulation of the SMEFT, which allows exact solutions, up to mass-dimension eight. Using this construction, we compare the exact solution to the expansion at ${\mathcal{O}}(v^2/\Lambda^2)$, partial ${\mathcal{O}}(v^4/\Lambda^4)$ using a subset of terms with dimension-6 operators, and full ${\mathcal{O}}(v^4/\Lambda^4)$, where $v$ is the vacuum expectation value and $\Lambda$ is the scale of new physics. This comparison is performed for general values of the coefficients, and for the specific model of a heavy U(1) gauge field kinetically mixed with the Standard Model. We additionally determine the input-parameter scheme dependence at all orders in $v/\Lambda$, and show that this dependence increases at higher orders in $v/\Lambda$. |
1201.1872 | Bernd Kniehl | Mathias Butenschoen, Bernd A. Kniehl | J/psi polarization at Tevatron and LHC: Nonrelativistic-QCD
factorization at the crossroads | 8 pages, 2 figures; minor changes to the text, 3 references added;
accepted for publication in Physical Review Letters | null | 10.1103/PhysRevLett.108.172002 | DESY 12-001 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the polarization observables of J/psi hadroproduction at
next-to-leading order within the factorization formalism of nonrelativistic
quantum chromodynamics. We complete the present knowledge of the relativistic
corrections by also providing the contribution due to the intermediate
^3P_J^{[8]} color-octet states at this order, which turns out to be quite
significant. Exploiting the color-octet long-distance matrix elements
previously extracted through a global fit to experimental data of unpolarized
J/psi production, we provide theoretical predictions in the helicity and
Collins-Soper frames and compare them with data taken by CDF at Fermilab
Tevatron I and II and by ALICE at CERN LHC. The notorious CDF J/psi
polarization anomaly familiar from leading-order analyses persists at the
quantum level, while the situation looks promising for the LHC, which is bound
to bring final clarification.
| [
{
"created": "Mon, 9 Jan 2012 18:57:31 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Mar 2012 13:59:11 GMT",
"version": "v2"
}
] | 2015-06-03 | [
[
"Butenschoen",
"Mathias",
""
],
[
"Kniehl",
"Bernd A.",
""
]
] | We study the polarization observables of J/psi hadroproduction at next-to-leading order within the factorization formalism of nonrelativistic quantum chromodynamics. We complete the present knowledge of the relativistic corrections by also providing the contribution due to the intermediate ^3P_J^{[8]} color-octet states at this order, which turns out to be quite significant. Exploiting the color-octet long-distance matrix elements previously extracted through a global fit to experimental data of unpolarized J/psi production, we provide theoretical predictions in the helicity and Collins-Soper frames and compare them with data taken by CDF at Fermilab Tevatron I and II and by ALICE at CERN LHC. The notorious CDF J/psi polarization anomaly familiar from leading-order analyses persists at the quantum level, while the situation looks promising for the LHC, which is bound to bring final clarification. |
1601.03044 | Logan Wille | Francis Halzen and Logan Wille | Upper Limit on Forward Charm Contribution to Atmospheric Neutrino Flux | null | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit the calculation of charm particle production in hadron collisions,
focusing on the production of charm particles that carry a large fraction of
the momentum of the incident proton. In the case of strange particles, such a
component is familiar from the abundant production of $K^+\Lambda$ pairs.
Modern collider experiments have no coverage in the very large rapidity region
where the forward pair production dominates. While forward charm particles are
produced inside the LHC beampipe, they dominate the high-energy atmospheric
neutrino flux in underground experiments because long-lived pions and kaons
interact before decaying into neutrinos. The fragmentation of the spectator
quark in the partonic subprocesses $qc \rightarrow qc$ and $gc \rightarrow gc$
is responsible for the forward component of charm production in perturbative
QCD. We use this phenomenological framework to construct a charm cross section
that saturates available accelerator and cosmic ray data, i.e., it represents
an upper limit on the normalization of the charm cross section that cannot be
reliably calculated because the charm mass is much smaller than the
center-of-mass energy. Where the highest energy IceCube observations are
concerned, we conclude that the upper limit on the flux of neutrinos from
forward charm production may dominate the much-studied central component. It
may therefore also represent a significant contribution to the TeV atmospheric
neutrino flux but cannot accommodate the PeV flux of high-energy cosmic
neutrinos observed by IceCube, or even the excess of events observed in the 30
TeV energy range.
| [
{
"created": "Tue, 12 Jan 2016 21:00:04 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Jan 2016 21:29:32 GMT",
"version": "v2"
},
{
"created": "Fri, 22 Jan 2016 21:08:07 GMT",
"version": "v3"
}
] | 2016-01-26 | [
[
"Halzen",
"Francis",
""
],
[
"Wille",
"Logan",
""
]
] | We revisit the calculation of charm particle production in hadron collisions, focusing on the production of charm particles that carry a large fraction of the momentum of the incident proton. In the case of strange particles, such a component is familiar from the abundant production of $K^+\Lambda$ pairs. Modern collider experiments have no coverage in the very large rapidity region where the forward pair production dominates. While forward charm particles are produced inside the LHC beampipe, they dominate the high-energy atmospheric neutrino flux in underground experiments because long-lived pions and kaons interact before decaying into neutrinos. The fragmentation of the spectator quark in the partonic subprocesses $qc \rightarrow qc$ and $gc \rightarrow gc$ is responsible for the forward component of charm production in perturbative QCD. We use this phenomenological framework to construct a charm cross section that saturates available accelerator and cosmic ray data, i.e., it represents an upper limit on the normalization of the charm cross section that cannot be reliably calculated because the charm mass is much smaller than the center-of-mass energy. Where the highest energy IceCube observations are concerned, we conclude that the upper limit on the flux of neutrinos from forward charm production may dominate the much-studied central component. It may therefore also represent a significant contribution to the TeV atmospheric neutrino flux but cannot accommodate the PeV flux of high-energy cosmic neutrinos observed by IceCube, or even the excess of events observed in the 30 TeV energy range. |
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