id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0801.3540 | Yanrui Liu | Yan-Rui Liu, Xiang Liu, Wei-Zhen Deng, Shi-Lin Zhu | Is X(3872) {\sl Really} a Molecular State? | 11 pages, 7 figures, 9 tables. The version to appear in EPJC | Eur.Phys.J.C56:63-73,2008 | 10.1140/epjc/s10052-008-0640-4 | null | hep-ph hep-ex hep-lat nucl-th | null | After taking into account both the pion and sigma meson exchange potential,
we have performed a dynamical calculation of the $D^0\bar{D}^{\ast0}$ system.
The $\sigma$ meson exchange potential is repulsive from heavy quark symmetry
and numerically important for a loosely bound system. Our analysis disfavors
the interpretation of X(3872) as a loosely bound molecular state if we use the
experimental $D^\ast D\pi$ coupling constant $g=0.59$ and a reasonable cutoff
around 1 GeV, which is the typical hadronic scale. Bound state solutions with
negative eigenvalues for the $D\bar{D}^\ast$ system exist only with either a
very large coupling constant (two times of the experimental value) or a large
cutoff ($\Lambda \sim 6$ GeV or $\beta \sim 6$ GeV$^2$). In contrast, there
probably exists a loosely bound S-wave $B\bar{B}^\ast$ molecular state. Once
produced, such a molecular state would be rather stable since its dominant
decay mode is the radiative decay through $B^\ast\to B \gamma$. Experimental
search of these states will be very interesting.
| [
{
"created": "Wed, 23 Jan 2008 16:03:29 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Apr 2008 16:42:53 GMT",
"version": "v2"
},
{
"created": "Tue, 13 May 2008 11:57:31 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Liu",
"Yan-Rui",
""
],
[
"Liu",
"Xiang",
""
],
[
"Deng",
"Wei-Zhen",
""
],
[
"Zhu",
"Shi-Lin",
""
]
] | After taking into account both the pion and sigma meson exchange potential, we have performed a dynamical calculation of the $D^0\bar{D}^{\ast0}$ system. The $\sigma$ meson exchange potential is repulsive from heavy quark symmetry and numerically important for a loosely bound system. Our analysis disfavors the interpretation of X(3872) as a loosely bound molecular state if we use the experimental $D^\ast D\pi$ coupling constant $g=0.59$ and a reasonable cutoff around 1 GeV, which is the typical hadronic scale. Bound state solutions with negative eigenvalues for the $D\bar{D}^\ast$ system exist only with either a very large coupling constant (two times of the experimental value) or a large cutoff ($\Lambda \sim 6$ GeV or $\beta \sim 6$ GeV$^2$). In contrast, there probably exists a loosely bound S-wave $B\bar{B}^\ast$ molecular state. Once produced, such a molecular state would be rather stable since its dominant decay mode is the radiative decay through $B^\ast\to B \gamma$. Experimental search of these states will be very interesting. |
hep-ph/9610249 | Sergey Troshin | Sergey M. Troshin | On the extreme behaviour of $g_1(x,Q^2)$ at $x\to 0$ | 4 pages, latex, enlarged, to be published in Phys. Lett. B | Phys.Lett. B397 (1997) 133-136 | 10.1016/S0370-2693(97)00164-0 | null | hep-ph | null | On the basis of the U-matrix form of s-channel unitarization, we consider
constraints unitarity provides for the spin structure function $g_1(x,Q^2)$ at
$x\to 0$. Corresponding constraint for the spin structure function $h_1(x,
Q^2)$ is given along.
| [
{
"created": "Fri, 4 Oct 1996 12:45:38 GMT",
"version": "v1"
},
{
"created": "Sat, 15 Feb 1997 13:25:16 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Troshin",
"Sergey M.",
""
]
] | On the basis of the U-matrix form of s-channel unitarization, we consider constraints unitarity provides for the spin structure function $g_1(x,Q^2)$ at $x\to 0$. Corresponding constraint for the spin structure function $h_1(x, Q^2)$ is given along. |
hep-ph/0111027 | Yuri Kubyshin | Yuri A. Kubyshin | Models with Extra Dimensions and Their Phenomenology | 52 pages, 15 postscript figures, LaTeX, based on the lectures given
at the XI School "Particles and Cosmology" (Baksan, April 18-24, 2001); new
references are added in the revised version | null | null | null | hep-ph | null | The Arkani-Hamed-Dimopoulos-Dvali and the Randall-Sundrum models with extra
spacelike dimensions, recently proposed as a solution to the hierarchy problem,
are reviewed. We discuss their basic properties and phenomenological effects of
particle interactions at high energies, predicted whithin these models.
| [
{
"created": "Fri, 2 Nov 2001 14:40:17 GMT",
"version": "v1"
},
{
"created": "Sat, 17 Nov 2001 16:30:57 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Kubyshin",
"Yuri A.",
""
]
] | The Arkani-Hamed-Dimopoulos-Dvali and the Randall-Sundrum models with extra spacelike dimensions, recently proposed as a solution to the hierarchy problem, are reviewed. We discuss their basic properties and phenomenological effects of particle interactions at high energies, predicted whithin these models. |
hep-ph/9502283 | Per Osland | Arild Skjold, Per Osland | Testing $CP$ in the Bjorken process | 15 pages, LaTex, plus 5 uuencoded figures attached Full ps file
available at ftp://vsfys1.fi.uib.no/anonymous/pub/BERGEN1995-02.ps | Nucl.Phys.B453:3-16,1995 | 10.1016/0550-3213(95)00373-Z | Bergen Scientific/Technical Report No. 1995-02 | hep-ph | null | In a more general electroweak theory, there could be Higgs particles that are
odd under $CP$, and also Higgs-like particles which are not eigenstates of
$CP$. We discuss distributions which for the Bjorken process are sensitive to
the $CP$ parity. Correlations among momenta of the initial electron and
final-state fermions yield this kind of information. We discuss also
observables which may demonstrate presence of $CP$ violation and identify a
phase shift $\delta$ which is a measure of the strength of $CP$ violation in
the Higgs-vector-vector coupling, and which can be measured directly in the
decay distribution. We present Monte Carlo data on the expected efficiency, and
conclude that it is relatively easy to determine whether the produced particle
is even or odd under $CP$. However, observation of any $CP$ violation would
require a very large amount of data.
| [
{
"created": "Mon, 13 Feb 1995 11:42:14 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Skjold",
"Arild",
""
],
[
"Osland",
"Per",
""
]
] | In a more general electroweak theory, there could be Higgs particles that are odd under $CP$, and also Higgs-like particles which are not eigenstates of $CP$. We discuss distributions which for the Bjorken process are sensitive to the $CP$ parity. Correlations among momenta of the initial electron and final-state fermions yield this kind of information. We discuss also observables which may demonstrate presence of $CP$ violation and identify a phase shift $\delta$ which is a measure of the strength of $CP$ violation in the Higgs-vector-vector coupling, and which can be measured directly in the decay distribution. We present Monte Carlo data on the expected efficiency, and conclude that it is relatively easy to determine whether the produced particle is even or odd under $CP$. However, observation of any $CP$ violation would require a very large amount of data. |
1606.07862 | Masaaki Kuroda | Masaaki Kuroda, Dieter Schildknecht | Color Dipole Picture of Deep Inelastic Scattering, Revisited | null | null | 10.1142/S0217751X16501578 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based upon the color-dipole picture, we provide closed analytic expressions
for the longitudinal and the transverse photoabsorption cross sections at low
values of the Bjorken variable of x<0.1. We compare with the experimental data
for the longitudinal-to-transverse ratio of the (virtual) photoabsorption cross
section and with our previous fit to the experimental data for the total
photoabsorption cross section. Scaling in terms of the low-x scaling variable
eta(W^2,Q^2) is analyzed in terms of the reduced cross section of deep
inelastic scattering.
| [
{
"created": "Sat, 25 Jun 2016 01:20:46 GMT",
"version": "v1"
}
] | 2016-11-23 | [
[
"Kuroda",
"Masaaki",
""
],
[
"Schildknecht",
"Dieter",
""
]
] | Based upon the color-dipole picture, we provide closed analytic expressions for the longitudinal and the transverse photoabsorption cross sections at low values of the Bjorken variable of x<0.1. We compare with the experimental data for the longitudinal-to-transverse ratio of the (virtual) photoabsorption cross section and with our previous fit to the experimental data for the total photoabsorption cross section. Scaling in terms of the low-x scaling variable eta(W^2,Q^2) is analyzed in terms of the reduced cross section of deep inelastic scattering. |
hep-ph/9402306 | P. A. Henning | P.A.Henning | A Transport Equation for Quantum Fields with Continuous Mass Spectrum | 25 pages LaTeX, 1 figure uuencoded, GSI-Preprint 94-13 | Nucl.Phys.A582:633-654,1995; ERRATUM-ibid.A586:777,1995 | 10.1016/0375-9474(94)00495-9 | null | hep-ph | null | Within a relativistic real-time Green's function formalism, a quantum
transport equation for the phase-space distribution function is derived without
a quasi-particle approximation. Dissipation is due to a nonzero spectral width,
and can be separated into time-local and memory effects.
| [
{
"created": "Thu, 17 Feb 1994 07:13:31 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Henning",
"P. A.",
""
]
] | Within a relativistic real-time Green's function formalism, a quantum transport equation for the phase-space distribution function is derived without a quasi-particle approximation. Dissipation is due to a nonzero spectral width, and can be separated into time-local and memory effects. |
hep-ph/9609318 | Robert Harris | Robert M. Harris (Fermilab) | Discovery Mass Reach for Topgluons Decaying to t anti-t at the Tevatron | 5 pages, 3 Figures, LaTex, macros epsf.sty, snowtimes.sty, and
snow2e.cls. To appear in the proceedings of DPF/DPB Summer Study on New
Directions for High Energy Physics, Snowmass, Colorado, June 25-July 12,
1996. Postscript file of full paper also available at
http://www-cdf.fnal.gov/physics/conf96/cdf3873_snow_topgluon_ttbar.ps | ECONFC960625:NEW166,1996 | null | Fermilab-Conf-96/277-E | hep-ph hep-ex | null | In topcolor assisted technicolor, topgluons are massive gluons which couple
mainly to top and bottom quarks. We estimate the mass reach for topgluons
decaying to t anti-t at the Tevatron as a function of integrated luminosity.
The mass reach for topgluons decreases with increasing topgluon width, and is
1.0 - 1.1 TeV for Run II (2 fb^-1) and 1.3-1.4 TeV for TeV33 (30 fb^-1).
| [
{
"created": "Wed, 11 Sep 1996 03:26:16 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Harris",
"Robert M.",
"",
"Fermilab"
]
] | In topcolor assisted technicolor, topgluons are massive gluons which couple mainly to top and bottom quarks. We estimate the mass reach for topgluons decaying to t anti-t at the Tevatron as a function of integrated luminosity. The mass reach for topgluons decreases with increasing topgluon width, and is 1.0 - 1.1 TeV for Run II (2 fb^-1) and 1.3-1.4 TeV for TeV33 (30 fb^-1). |
2112.05967 | Hongxia Huang | Yuheng Wu, Xin Jin, Runxin Liu, Hongxia Huang and Jialun Ping | The study of double-charm and double-strange tetraquarks | 8 pages, 3 figures | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | In the framework of the quark delocalization color screening model (QDCSM),
we systematically investigate the double-charm and double-strange tetraquark
systems $cc\bar{s}\bar{s}$ with two structures: meson-meson and
diquark-antidiquark. The bound-state calculation shows that there is no any
bound state in present work. However, by applying a stabilization calculation
and coupling all channels of both two structures, two new resonance states with
$IJ^{P}=00^{+}$ are obtained. One is more possible to be a molecular resonance
state with a mass and width around $4256$ MeV and $60$ MeV, respectively;
another one is more likely to be a compact resonance state with a mass and
width around $4308$ MeV and $19$ MeV, respectively. Although no significant
signals were observed in present experiment at the Belle collaboration, there
is still some structures around $4.3$ GeV in the distributions of
$M_{D^{+}_{s}D^{+}_{s}}$ and $M_{D^{*+}_{s}D^{*+}_{s}}$. We suggest that the
experiment can be further tested with a larger amount of data.
| [
{
"created": "Sat, 11 Dec 2021 12:39:05 GMT",
"version": "v1"
}
] | 2021-12-14 | [
[
"Wu",
"Yuheng",
""
],
[
"Jin",
"Xin",
""
],
[
"Liu",
"Runxin",
""
],
[
"Huang",
"Hongxia",
""
],
[
"Ping",
"Jialun",
""
]
] | In the framework of the quark delocalization color screening model (QDCSM), we systematically investigate the double-charm and double-strange tetraquark systems $cc\bar{s}\bar{s}$ with two structures: meson-meson and diquark-antidiquark. The bound-state calculation shows that there is no any bound state in present work. However, by applying a stabilization calculation and coupling all channels of both two structures, two new resonance states with $IJ^{P}=00^{+}$ are obtained. One is more possible to be a molecular resonance state with a mass and width around $4256$ MeV and $60$ MeV, respectively; another one is more likely to be a compact resonance state with a mass and width around $4308$ MeV and $19$ MeV, respectively. Although no significant signals were observed in present experiment at the Belle collaboration, there is still some structures around $4.3$ GeV in the distributions of $M_{D^{+}_{s}D^{+}_{s}}$ and $M_{D^{*+}_{s}D^{*+}_{s}}$. We suggest that the experiment can be further tested with a larger amount of data. |
2309.03706 | Murat Abdughani | Murat Abdughani and Yakefu Reyimuaji | Constraining light dark matter and mediator with $B^+ \rightarrow K^+
\nu \bar \nu$ data | 11 pages, 3 figures | null | null | null | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | We study the decay of $B^+$ meson into $K^+$ plus a light mediator $\phi$
followed by production of dark matter (DM) pair $\bar \chi \chi$, which can
mimic the flavor changing neural current (FCNC) process of $B^+ \rightarrow K^+
\nu \bar \nu$ in the standard model (SM). Constraints from DM relic density,
direct detection, collider and $B-$physics data combined with the recently
reported $B^+\rightarrow K^+ \nu \bar \nu$ branching ratio performed at the
Belle II experiment, we analyse couplings between the mediator and the SM
fermions as well as the dark matter particle. We obtain that: if the process
$\phi \rightarrow \bar \chi \chi$ is kinematically allowed, i.e. $m_\phi >
2m_\chi$, then $m_\phi$ should be larger than mass of the muon pair; Otherwise,
$\phi$ should play the role of missing energy, and only allowed decaying
channel is $\phi \rightarrow e^+ e^-$.
| [
{
"created": "Thu, 7 Sep 2023 13:33:04 GMT",
"version": "v1"
}
] | 2023-09-08 | [
[
"Abdughani",
"Murat",
""
],
[
"Reyimuaji",
"Yakefu",
""
]
] | We study the decay of $B^+$ meson into $K^+$ plus a light mediator $\phi$ followed by production of dark matter (DM) pair $\bar \chi \chi$, which can mimic the flavor changing neural current (FCNC) process of $B^+ \rightarrow K^+ \nu \bar \nu$ in the standard model (SM). Constraints from DM relic density, direct detection, collider and $B-$physics data combined with the recently reported $B^+\rightarrow K^+ \nu \bar \nu$ branching ratio performed at the Belle II experiment, we analyse couplings between the mediator and the SM fermions as well as the dark matter particle. We obtain that: if the process $\phi \rightarrow \bar \chi \chi$ is kinematically allowed, i.e. $m_\phi > 2m_\chi$, then $m_\phi$ should be larger than mass of the muon pair; Otherwise, $\phi$ should play the role of missing energy, and only allowed decaying channel is $\phi \rightarrow e^+ e^-$. |
1010.0378 | Heli Honkanen | H. Honkanen | Electron in a transverse harmonic potential | 8 pages, 4 figures, Presented at Light Cone 2010: Relativistic
Hadronic and Particle Physics, June 14-18, 2010, Valencia, Spain | PoS LC2010:004,2010 | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Non-perturbative solutions to the quantum-field theory is a topic of current
and broad interest, especially for the heavy ion and laser physics communities,
since they investigate particle production in the presence of strong external
fields. We have solved a non-perturbative QED + external field problem of an
electron in a strong transverse confining potential using Hamiltonian
light-front quantum field theory in a basis function representation. The
invariant mass spectra and the anomalous magnetic moment of the lowest state
for this two-scale system are also evaluated. With this method the perturbative
QED results are also reproduced with a good accuracy. We also discuss the
extension of the method to other problems as well.
| [
{
"created": "Sun, 3 Oct 2010 04:43:25 GMT",
"version": "v1"
}
] | 2015-03-17 | [
[
"Honkanen",
"H.",
""
]
] | Non-perturbative solutions to the quantum-field theory is a topic of current and broad interest, especially for the heavy ion and laser physics communities, since they investigate particle production in the presence of strong external fields. We have solved a non-perturbative QED + external field problem of an electron in a strong transverse confining potential using Hamiltonian light-front quantum field theory in a basis function representation. The invariant mass spectra and the anomalous magnetic moment of the lowest state for this two-scale system are also evaluated. With this method the perturbative QED results are also reproduced with a good accuracy. We also discuss the extension of the method to other problems as well. |
1710.05934 | Viktor Begun | Viktor Begun | Resonances in a sudden chemical freeze-out model | Minor changes on the request of a referee | null | 10.1051/epjconf/201817115002 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The prediction for $p_T$ spectra of various resonances produced in Pb+Pb
collisions at 2.76 TeV at the LHC in equilibrium and non-equilibrium models is
made. It includes the $\eta$, $\rho$(770), $\Sigma$(1385), $\Lambda$(1520), and
$\Xi$(1530). The apparent differences may allow to distinguish between the
models.
| [
{
"created": "Mon, 16 Oct 2017 18:00:18 GMT",
"version": "v1"
},
{
"created": "Thu, 2 Nov 2017 19:04:27 GMT",
"version": "v2"
},
{
"created": "Fri, 8 Dec 2017 10:41:56 GMT",
"version": "v3"
}
] | 2018-03-14 | [
[
"Begun",
"Viktor",
""
]
] | The prediction for $p_T$ spectra of various resonances produced in Pb+Pb collisions at 2.76 TeV at the LHC in equilibrium and non-equilibrium models is made. It includes the $\eta$, $\rho$(770), $\Sigma$(1385), $\Lambda$(1520), and $\Xi$(1530). The apparent differences may allow to distinguish between the models. |
hep-ph/0610040 | Arlene Cristina Aguilar | Arlene C. Aguilar and Joannis Papavassiliou | Gluon mass generation in the PT-BFM scheme | 54 pages, 24 figures | JHEP0612:012,2006 | 10.1088/1126-6708/2006/12/012 | null | hep-ph hep-lat hep-th | null | In this article we study the general structure and special properties of the
Schwinger-Dyson equation for the gluon propagator constructed with the pinch
technique, together with the question of how to obtain infrared finite
solutions, associated with the generation of an effective gluon mass.
Exploiting the known all-order correspondence between the pinch technique and
the background field method, we demonstrate that, contrary to the standard
formulation, the non-perturbative gluon self-energy is transverse
order-by-order in the dressed loop expansion, and separately for gluonic and
ghost contributions. We next present a comprehensive review of several subtle
issues relevant to the search of infrared finite solutions, paying particular
attention to the role of the seagull graph in enforcing transversality, the
necessity of introducing massless poles in the three-gluon vertex, and the
incorporation of the correct renormalization group properties. In addition, we
present a method for regulating the seagull-type contributions based on
dimensional regularization; its applicability depends crucially on the
asymptotic behavior of the solutions in the deep ultraviolet, and in particular
on the anomalous dimension of the dynamically generated gluon mass. A
linearized version of the truncated Schwinger-Dyson equation is derived, using
a vertex that satisfies the required Ward identity and contains massless poles
belonging to different Lorentz structures. The resulting integral equation is
then solved numerically, the infrared and ultraviolet properties of the
obtained solutions are examined in detail, and the allowed range for the
effective gluon mass is determined. Various open questions and possible
connections with different approaches in the literature are discussed.
| [
{
"created": "Tue, 3 Oct 2006 21:36:23 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Aguilar",
"Arlene C.",
""
],
[
"Papavassiliou",
"Joannis",
""
]
] | In this article we study the general structure and special properties of the Schwinger-Dyson equation for the gluon propagator constructed with the pinch technique, together with the question of how to obtain infrared finite solutions, associated with the generation of an effective gluon mass. Exploiting the known all-order correspondence between the pinch technique and the background field method, we demonstrate that, contrary to the standard formulation, the non-perturbative gluon self-energy is transverse order-by-order in the dressed loop expansion, and separately for gluonic and ghost contributions. We next present a comprehensive review of several subtle issues relevant to the search of infrared finite solutions, paying particular attention to the role of the seagull graph in enforcing transversality, the necessity of introducing massless poles in the three-gluon vertex, and the incorporation of the correct renormalization group properties. In addition, we present a method for regulating the seagull-type contributions based on dimensional regularization; its applicability depends crucially on the asymptotic behavior of the solutions in the deep ultraviolet, and in particular on the anomalous dimension of the dynamically generated gluon mass. A linearized version of the truncated Schwinger-Dyson equation is derived, using a vertex that satisfies the required Ward identity and contains massless poles belonging to different Lorentz structures. The resulting integral equation is then solved numerically, the infrared and ultraviolet properties of the obtained solutions are examined in detail, and the allowed range for the effective gluon mass is determined. Various open questions and possible connections with different approaches in the literature are discussed. |
1808.10565 | Zhun Lu | Yongliang Yang, Wenjuan Mao, Zhun Lu | Single Spin Asymmetry in transverse polarized proton production and
lambda production in Semi-Inclusive DIS at twist-3 | 13 pages, 10 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the single spin asymmetry in the transversely polarized proton
production and the lambda hyperon production in semi-inclusive deep inelastic
scattering with a $\sin \phi_{S_h}$ modulation, in which $S_h$ is the azimuthal
angle of the transverse spin of the final hadron. The theoretical
interpretation for the asymmetry is presented as the convolution of the twist-3
quark transverse momentum dependent distributions and twist-2 fragmentation
functions. We investigate the role of the twist-3 distribution functions $h(x,
p_T^2)$, $f^\perp(x, p_T^2)$ and $g^\perp(x, p_T^2)$ and the twist-2
fragmentation functions $H_1(x, k_T^2)$, $D_{1T}^\perp(x, k_T^2)$ and
$G_{1T}(x, k_T^2)$ in this asymmetry. Using spectator model, we compute these
distribution and fragmentation functions and estimate the $\sin \phi_{S_h}$
asymmetry for the proton production as well as for the lambda production at
JLab with a 12 $\mathrm{GeV}$ electron beam. The asymmetry at the COMPASS
kinematics is also predicted. By comparing different sources for the asymmetry,
we conclude that it is feasible to access the distribution function $h$ and the
fragmentation function $H_1$ through measuring the asymmetry in the proton
production, whereas the $f^\perp \,D_{1T}^\perp$ term might be probed in the
lambda production at JLab 12 GeV.
| [
{
"created": "Fri, 31 Aug 2018 01:37:33 GMT",
"version": "v1"
}
] | 2018-09-03 | [
[
"Yang",
"Yongliang",
""
],
[
"Mao",
"Wenjuan",
""
],
[
"Lu",
"Zhun",
""
]
] | We study the single spin asymmetry in the transversely polarized proton production and the lambda hyperon production in semi-inclusive deep inelastic scattering with a $\sin \phi_{S_h}$ modulation, in which $S_h$ is the azimuthal angle of the transverse spin of the final hadron. The theoretical interpretation for the asymmetry is presented as the convolution of the twist-3 quark transverse momentum dependent distributions and twist-2 fragmentation functions. We investigate the role of the twist-3 distribution functions $h(x, p_T^2)$, $f^\perp(x, p_T^2)$ and $g^\perp(x, p_T^2)$ and the twist-2 fragmentation functions $H_1(x, k_T^2)$, $D_{1T}^\perp(x, k_T^2)$ and $G_{1T}(x, k_T^2)$ in this asymmetry. Using spectator model, we compute these distribution and fragmentation functions and estimate the $\sin \phi_{S_h}$ asymmetry for the proton production as well as for the lambda production at JLab with a 12 $\mathrm{GeV}$ electron beam. The asymmetry at the COMPASS kinematics is also predicted. By comparing different sources for the asymmetry, we conclude that it is feasible to access the distribution function $h$ and the fragmentation function $H_1$ through measuring the asymmetry in the proton production, whereas the $f^\perp \,D_{1T}^\perp$ term might be probed in the lambda production at JLab 12 GeV. |
1012.5935 | Kazem Azizi | T. M. Aliev, K. Azizi, M. Savci | Spin--3/2 to spin--1/2 heavy baryons and pseudoscalar mesons transitions
in QCD | 17 Pages, 4 Figures and 5 Tables | null | 10.1140/epjc/s10052-011-1675-5 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The strong coupling constants of light pseudoscalar mesons with spin--3/2 and
spin--1/2 heavy baryons are calculated in the framework of light cone QCD sum
rules. It is shown that each class of transitions among members of the sextet
spin--3/2 to sextet spin--1/2 baryons and that of the sextet spin--3/2 to
spin--1/2 anti--triplet baryons is described by only one invariant function. We
also estimate the widths of kinematically allowed transitions. Our results on
decay widths are in good agreement with the existing experimental data, as well
as predictions of other nonperturbative approaches.
| [
{
"created": "Wed, 29 Dec 2010 13:23:05 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Feb 2011 06:54:07 GMT",
"version": "v2"
},
{
"created": "Thu, 5 May 2011 17:02:59 GMT",
"version": "v3"
}
] | 2015-05-20 | [
[
"Aliev",
"T. M.",
""
],
[
"Azizi",
"K.",
""
],
[
"Savci",
"M.",
""
]
] | The strong coupling constants of light pseudoscalar mesons with spin--3/2 and spin--1/2 heavy baryons are calculated in the framework of light cone QCD sum rules. It is shown that each class of transitions among members of the sextet spin--3/2 to sextet spin--1/2 baryons and that of the sextet spin--3/2 to spin--1/2 anti--triplet baryons is described by only one invariant function. We also estimate the widths of kinematically allowed transitions. Our results on decay widths are in good agreement with the existing experimental data, as well as predictions of other nonperturbative approaches. |
hep-ph/9601337 | Georgios Leontaris | G. K. Leontaris | A String Model with $SU(4)\times O(4)\times [Sp(4)]_{Hidden}$ Gauge
Symmetry | LateX file, 12pp, no figures (Phys.Lett.B) | Phys.Lett. B372 (1996) 212-218 | 10.1016/0370-2693(96)00059-7 | IOA-335/95 | hep-ph | null | In the four dimensional free fermionic formulation of the heterotic string, a
semi-realistic $SU(4)\times SU(2)_L \times SU(2)_R$ model is proposed with
three fermion generations in $(4,2,1)+(\bar 4,1,2)$ representations. The gauge
symmetry of the model breaks to the standard gauge group using a higgs pair in
the $(4,1,2)+(\bar 4,1,2)$ representations. The massless spectrum includes
exotic fractionally charged states with non -- trivial transformation
properties under part ($Sp(4)$) of the non -- abelian `hidden' symmetry.
Finally there is a mirror pair in $(4,2,1) , (\bar 4,2,1)$ allowing the
possibility for an identical running of $g_{4,L,R}$ couplings between the
string and $SU(4)$ breaking scales. This is of crucial importance for a
successful prediction of the weak mixing angle. Potential shortcomings and
problems of the construction are analysed and possible solutions are discussed.
| [
{
"created": "Thu, 25 Jan 1996 20:21:06 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Leontaris",
"G. K.",
""
]
] | In the four dimensional free fermionic formulation of the heterotic string, a semi-realistic $SU(4)\times SU(2)_L \times SU(2)_R$ model is proposed with three fermion generations in $(4,2,1)+(\bar 4,1,2)$ representations. The gauge symmetry of the model breaks to the standard gauge group using a higgs pair in the $(4,1,2)+(\bar 4,1,2)$ representations. The massless spectrum includes exotic fractionally charged states with non -- trivial transformation properties under part ($Sp(4)$) of the non -- abelian `hidden' symmetry. Finally there is a mirror pair in $(4,2,1) , (\bar 4,2,1)$ allowing the possibility for an identical running of $g_{4,L,R}$ couplings between the string and $SU(4)$ breaking scales. This is of crucial importance for a successful prediction of the weak mixing angle. Potential shortcomings and problems of the construction are analysed and possible solutions are discussed. |
1105.2067 | Richard Neufeld Jr. | R. B. Neufeld, Ivan Vitev | Parton showers as sources of energy-momentum deposition in the QGP and
their implication for shockwave formation at RHIC and at the LHC | 8 pages, 4 figures | null | 10.1103/PhysRevC.86.024905 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive the distribution of energy and momentum transmitted from a primary
fast parton and its medium-induced bremsstrahlung gluons to a thermalized
quark-gluon plasma. Our calculation takes into account the important and thus
far neglected effects of quantum interference between the resulting color
currents. We use our result to obtain the rate at which energy is absorbed by
the medium as a function of time and find that the rate is modified by the
quantum interference between the primary parton and secondary gluons. This
Landau-Pomeranchuk-Migdal type interference persists for time scales relevant
to heavy ion phenomenology. We further couple the newly derived source of
energy and momentum deposition to linearized hydrodynamics to obtain the bulk
medium response to realistic parton propagation and splitting in the
quark-gluon plasma. We find that because of the characteristic large angle
in-medium gluon emission and the multiple sources of energy deposition in a
parton shower, formation of well defined Mach cones by energetic jets in heavy
ion reactions is not likely.
| [
{
"created": "Tue, 10 May 2011 22:42:34 GMT",
"version": "v1"
}
] | 2015-05-28 | [
[
"Neufeld",
"R. B.",
""
],
[
"Vitev",
"Ivan",
""
]
] | We derive the distribution of energy and momentum transmitted from a primary fast parton and its medium-induced bremsstrahlung gluons to a thermalized quark-gluon plasma. Our calculation takes into account the important and thus far neglected effects of quantum interference between the resulting color currents. We use our result to obtain the rate at which energy is absorbed by the medium as a function of time and find that the rate is modified by the quantum interference between the primary parton and secondary gluons. This Landau-Pomeranchuk-Migdal type interference persists for time scales relevant to heavy ion phenomenology. We further couple the newly derived source of energy and momentum deposition to linearized hydrodynamics to obtain the bulk medium response to realistic parton propagation and splitting in the quark-gluon plasma. We find that because of the characteristic large angle in-medium gluon emission and the multiple sources of energy deposition in a parton shower, formation of well defined Mach cones by energetic jets in heavy ion reactions is not likely. |
2406.17599 | Christoph Andreas Ternes | D. Barducci, E. Bertuzzo, M. Taoso, C. A. Ternes, C. Toni | Illuminating the dark: mono-$\gamma$ signals at NA62 | v1: 18 pages, 4 figures, 1 table | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | Dipole interactions between dark sector states or between a Standard Model
particle and a dark state can efficiently be searched for via high-intensity
fixed-target facilities. We propose to look for the associated mono-$\gamma$
signature at the NA62 experiment running in beam-dump mode. Focusing on models
of dipole inelastic Dark Matter and active-sterile neutrino dipole
interactions, we compute the corresponding expected sensitivities finding
promising prospects for discovery.
| [
{
"created": "Tue, 25 Jun 2024 14:41:29 GMT",
"version": "v1"
}
] | 2024-06-26 | [
[
"Barducci",
"D.",
""
],
[
"Bertuzzo",
"E.",
""
],
[
"Taoso",
"M.",
""
],
[
"Ternes",
"C. A.",
""
],
[
"Toni",
"C.",
""
]
] | Dipole interactions between dark sector states or between a Standard Model particle and a dark state can efficiently be searched for via high-intensity fixed-target facilities. We propose to look for the associated mono-$\gamma$ signature at the NA62 experiment running in beam-dump mode. Focusing on models of dipole inelastic Dark Matter and active-sterile neutrino dipole interactions, we compute the corresponding expected sensitivities finding promising prospects for discovery. |
0904.4732 | Bipin singh Koranga | Bipin Singh Koranga (Delhi U.) | Neutrino Oscillation Probability from Tri-Bimaximality due to Planck
Scale Effects | 7 pages | Electron.J.Theor.Phys.6:1-8,2009 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Current neutrino experimental data on neutrino mixing are well describes by
Tri-bi-maximal mixing, which is predicts sin^{2}\theta_{12}=1/3,zero U_{e3} and
\theta_{23}=45^{o}. We consider the planck scale operator on neutrino mixing.
We assume that the neutrino masses and mixing arise through physics at a scale
intrimediate between planck scale and the electroweak braking scale. We also
assume, that just above the electroweak breaking scale neutrino mass are nearly
degenerate and the mixing is tri-bi-maximal. Quantum gravity (Planck scale)
effects lead to an effective SU(2)_{L}\times U(1) invariant dimension-5
Lagrangian symmetry involving Standard Model. On electroweak symmetry breaking,
this operator gives rise to correction to the neutrino masses and mixings these
additional terms can be considered as perturbation to the tri-bimaximal
neutrino mass matrix. We compute the deviation of the three mixing angles and
oscillation probability. We find that the only large change in solar mixing
angle and % change in maximum P_{\mu e} is about 10%.
| [
{
"created": "Thu, 30 Apr 2009 01:50:09 GMT",
"version": "v1"
}
] | 2009-05-01 | [
[
"Koranga",
"Bipin Singh",
"",
"Delhi U."
]
] | Current neutrino experimental data on neutrino mixing are well describes by Tri-bi-maximal mixing, which is predicts sin^{2}\theta_{12}=1/3,zero U_{e3} and \theta_{23}=45^{o}. We consider the planck scale operator on neutrino mixing. We assume that the neutrino masses and mixing arise through physics at a scale intrimediate between planck scale and the electroweak braking scale. We also assume, that just above the electroweak breaking scale neutrino mass are nearly degenerate and the mixing is tri-bi-maximal. Quantum gravity (Planck scale) effects lead to an effective SU(2)_{L}\times U(1) invariant dimension-5 Lagrangian symmetry involving Standard Model. On electroweak symmetry breaking, this operator gives rise to correction to the neutrino masses and mixings these additional terms can be considered as perturbation to the tri-bimaximal neutrino mass matrix. We compute the deviation of the three mixing angles and oscillation probability. We find that the only large change in solar mixing angle and % change in maximum P_{\mu e} is about 10%. |
1509.06130 | Grigorii Pivovarov | Grigorii B. Pivovarov | Gell-Mann--Low scheme for the Standard Model | 8 pages; based on a talk given at HADRON STRUCTURE '15; to appear in
the Proceedings | null | 10.1142/S2010194515600848 | Preprint INR-TH-2015-024 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I describe a version of the Gell-Mann--Low scheme which is applicable to the
Standard Model. First, I give a procedure for extracting input parameters of
the theory from the Green's functions. After that, an iterative procedure of
expressing the Green's functions in terms of the above parameters is given.
| [
{
"created": "Mon, 21 Sep 2015 07:43:45 GMT",
"version": "v1"
}
] | 2015-12-09 | [
[
"Pivovarov",
"Grigorii B.",
""
]
] | I describe a version of the Gell-Mann--Low scheme which is applicable to the Standard Model. First, I give a procedure for extracting input parameters of the theory from the Green's functions. After that, an iterative procedure of expressing the Green's functions in terms of the above parameters is given. |
hep-ph/0010184 | Eric Laenen | Eric Laenen, George Sterman, Werner Vogelsang | Combined recoil and threshold resummation for hard scattering cross
sections | 4 pages, LaTeX, 2 figs. Contributed to 30th International Conference
on High-Energy Physics (ICHEP 2000), Osaka, Japan, 27 Jul - 2 Aug 2000 | null | null | NIKHEF/00-30, YITP-SB-00-65, BNL-HET-00/39, RBREC 145 | hep-ph | null | We discuss the simultaneous resummation of threshold and recoil enhancements
to partonic cross sections due to soft radiation. Our method is based on a
refactorization of the parton cross section near its partonic threshold. It
avoids double counting, conserves the flow of partonic energy, and reproduces
either threshold or recoil resummation when the other enhancements are
neglected.
| [
{
"created": "Tue, 17 Oct 2000 11:26:58 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Laenen",
"Eric",
""
],
[
"Sterman",
"George",
""
],
[
"Vogelsang",
"Werner",
""
]
] | We discuss the simultaneous resummation of threshold and recoil enhancements to partonic cross sections due to soft radiation. Our method is based on a refactorization of the parton cross section near its partonic threshold. It avoids double counting, conserves the flow of partonic energy, and reproduces either threshold or recoil resummation when the other enhancements are neglected. |
hep-ph/0112263 | Pedro Pacheco de Queiroz Filho | Pedro Pacheco de Queiroz Filho and Jorge Eduardo Cieza Montalvo | Heavy-Exotic-Leptons at LHC | 6 pages and 7 eps-figures | null | null | DFNAE-IF/UERJ-01/21 | hep-ph | null | We investigate the production, signatures and backgrounds of a pair of
heavy-exotic charged leptons and a heavy-exotic neutrino together with the
exotic charged lepton in the framework of the vector singlet model, vector
doublet model, and fermion-mirror-fermion model, at the CERN Large Hadron
Collider (LHC). We still show that the cross-sections for the case of the
production of a pair of heavy exotic leptons are competitive with the ones for
the single production of exotic leptons.
| [
{
"created": "Wed, 19 Dec 2001 19:28:33 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Dec 2001 20:39:58 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Filho",
"Pedro Pacheco de Queiroz",
""
],
[
"Montalvo",
"Jorge Eduardo Cieza",
""
]
] | We investigate the production, signatures and backgrounds of a pair of heavy-exotic charged leptons and a heavy-exotic neutrino together with the exotic charged lepton in the framework of the vector singlet model, vector doublet model, and fermion-mirror-fermion model, at the CERN Large Hadron Collider (LHC). We still show that the cross-sections for the case of the production of a pair of heavy exotic leptons are competitive with the ones for the single production of exotic leptons. |
1104.3450 | Nan Su | Nan Su | A Gauge-Invariant Reorganization of Thermal Gauge Theory | Doctoral dissertation, Goethe-Universitaet Frankfurt, 152 pp., Aug.
2010. Official version available from
http://publikationen.ub.uni-frankfurt.de/volltexte/2011/8962/ | null | null | null | hep-ph hep-lat hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This dissertation is devoted to the study of thermodynamics for quantum gauge
theories. The poor convergence of quantum field theory at finite temperature
has been the main obstacle in the practical applications of thermal QCD for
decades. In this dissertation I apply hard-thermal-loop perturbation theory,
which is a gauge-invariant reorganization of the conventional perturbative
expansion for quantum gauge theories to the thermodynamics of QED and
Yang-Mills theory to three-loop order. For the Abelian case, I present a
calculation of the free energy of a hot gas of electrons and photons by
expanding in a power series in $m_D/T$, $m_f/T$ and $e^2$, where $m_D$ and
$m_f$ are the photon and electron thermal masses, respectively, and $e$ is the
coupling constant. I demonstrate that the hard-thermal-loop perturbation
reorganization improves the convergence of the successive approximations to the
QED free energy at large coupling, $e \sim 2$. For the non-Abelian case, I
present a calculation of the free energy of a hot gas of gluons by expanding in
a power series in $m_D/T$ and $g^2$, where $m_D$ is the gluon thermal mass and
$g$ is the coupling constant. I show that at three-loop order hard-thermal-loop
perturbation theory is compatible with lattice results for the pressure, energy
density, and entropy down to temperatures $T \sim 2-3\;T_c$. The results
suggest that HTLpt provides a systematic framework that can be used to
calculate static and dynamic quantities for temperatures relevant at LHC.
| [
{
"created": "Mon, 18 Apr 2011 12:20:27 GMT",
"version": "v1"
},
{
"created": "Fri, 6 May 2011 14:36:58 GMT",
"version": "v2"
}
] | 2011-05-09 | [
[
"Su",
"Nan",
""
]
] | This dissertation is devoted to the study of thermodynamics for quantum gauge theories. The poor convergence of quantum field theory at finite temperature has been the main obstacle in the practical applications of thermal QCD for decades. In this dissertation I apply hard-thermal-loop perturbation theory, which is a gauge-invariant reorganization of the conventional perturbative expansion for quantum gauge theories to the thermodynamics of QED and Yang-Mills theory to three-loop order. For the Abelian case, I present a calculation of the free energy of a hot gas of electrons and photons by expanding in a power series in $m_D/T$, $m_f/T$ and $e^2$, where $m_D$ and $m_f$ are the photon and electron thermal masses, respectively, and $e$ is the coupling constant. I demonstrate that the hard-thermal-loop perturbation reorganization improves the convergence of the successive approximations to the QED free energy at large coupling, $e \sim 2$. For the non-Abelian case, I present a calculation of the free energy of a hot gas of gluons by expanding in a power series in $m_D/T$ and $g^2$, where $m_D$ is the gluon thermal mass and $g$ is the coupling constant. I show that at three-loop order hard-thermal-loop perturbation theory is compatible with lattice results for the pressure, energy density, and entropy down to temperatures $T \sim 2-3\;T_c$. The results suggest that HTLpt provides a systematic framework that can be used to calculate static and dynamic quantities for temperatures relevant at LHC. |
1710.02425 | Shao-Jiang Wang | Rong-Gen Cai, Tong-Bo Liu, Shao-Jiang Wang | Gravitational wave as probe of superfluid dark matter | v1, 10 pages, 2 figures, two columns; v2, 12 pages, 2 figures, two
columns, references are added, a summary for GW velocity constraints is
added, a discussion on Shapiro time delay is added; v3, 13 pages, 2 figures,
two columns, final version to match the published version | Phys. Rev. D 97, 023027 (2018) | 10.1103/PhysRevD.97.023027 | null | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In recent years, superfluid dark matter (SfDM) has become a competitive model
of emergent modified Newtonian dynamics (MOND) scenario: MOND phenomenons
naturally emerge as a derived concept due to an extra force mediated between
baryons by phonons as a result of axionlike particles condensed as superfluid
at galactic scales; Beyond galactic scales, these axionlike particles behave as
normal fluid without phonon-mediated MOND-like force between baryons, therefore
SfDM also maintains the usual success of $\Lambda$CDM at cosmological scales.
In this paper, we use gravitational waves (GWs) to probe the relevant parameter
space of SfDM. GWs through Bose-Einstein condensate (BEC) could propagate with
a speed slightly deviation from the speed-of-light due to the change in the
effective refractive index, which depends on the SfDM parameters and GW-source
properties. We find that Five hundred meter Aperture Spherical Telescope
(FAST), Square Kilometre Array (SKA) and International Pulsar Timing Array
(IPTA) are the most promising means as GW probe of relevant parameter space of
SfDM. Future space-based GW detectors are also capable of probing SfDM if a
multimessenger approach is adopted.
| [
{
"created": "Fri, 6 Oct 2017 14:32:32 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Oct 2017 17:24:14 GMT",
"version": "v2"
},
{
"created": "Wed, 7 Feb 2018 15:30:48 GMT",
"version": "v3"
}
] | 2018-02-08 | [
[
"Cai",
"Rong-Gen",
""
],
[
"Liu",
"Tong-Bo",
""
],
[
"Wang",
"Shao-Jiang",
""
]
] | In recent years, superfluid dark matter (SfDM) has become a competitive model of emergent modified Newtonian dynamics (MOND) scenario: MOND phenomenons naturally emerge as a derived concept due to an extra force mediated between baryons by phonons as a result of axionlike particles condensed as superfluid at galactic scales; Beyond galactic scales, these axionlike particles behave as normal fluid without phonon-mediated MOND-like force between baryons, therefore SfDM also maintains the usual success of $\Lambda$CDM at cosmological scales. In this paper, we use gravitational waves (GWs) to probe the relevant parameter space of SfDM. GWs through Bose-Einstein condensate (BEC) could propagate with a speed slightly deviation from the speed-of-light due to the change in the effective refractive index, which depends on the SfDM parameters and GW-source properties. We find that Five hundred meter Aperture Spherical Telescope (FAST), Square Kilometre Array (SKA) and International Pulsar Timing Array (IPTA) are the most promising means as GW probe of relevant parameter space of SfDM. Future space-based GW detectors are also capable of probing SfDM if a multimessenger approach is adopted. |
1712.04966 | Namrata Manglani | F. Mahmoudi, N. Manglani and K. Sridhar | The bulk Higgs in the Deformed RS Model | 11 pages | Phys.Lett. B784 (2018) 330-335 | 10.1016/j.physletb.2018.08.007 | CERN-TH-2017-260, TIFR/TH/17-44 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Randall-Sundrum model with a deformed metric can generate light
Kaluza-Klein (KK) Higgs modes consistent with the electroweak precision
analysis for a certain range of parameters. The first KK mode of the Higgs
($h_{1}$) in such a model could lie in the mass range varying from 800 GeV to
1.3 TeV. We find that the $h_{1}$ is gaugephobic and decays dominantly into a
$t\bar{t}$ pair. The search strategy for $h_{1}$ decaying to $t\bar{t}$ at the
Large Hadron Collider (LHC) in this low mass range has been studies. We have
used substructure tools to suppress the large QCD background associated with
this channel. We find that $h_{1}$ can be probed at the LHC.
| [
{
"created": "Wed, 13 Dec 2017 19:21:55 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Sep 2018 09:27:50 GMT",
"version": "v2"
}
] | 2018-09-10 | [
[
"Mahmoudi",
"F.",
""
],
[
"Manglani",
"N.",
""
],
[
"Sridhar",
"K.",
""
]
] | The Randall-Sundrum model with a deformed metric can generate light Kaluza-Klein (KK) Higgs modes consistent with the electroweak precision analysis for a certain range of parameters. The first KK mode of the Higgs ($h_{1}$) in such a model could lie in the mass range varying from 800 GeV to 1.3 TeV. We find that the $h_{1}$ is gaugephobic and decays dominantly into a $t\bar{t}$ pair. The search strategy for $h_{1}$ decaying to $t\bar{t}$ at the Large Hadron Collider (LHC) in this low mass range has been studies. We have used substructure tools to suppress the large QCD background associated with this channel. We find that $h_{1}$ can be probed at the LHC. |
2208.02643 | Aleksey Rusov | Alexander Lenz, Maria Laura Piscopo, Aleksey V. Rusov | Disintegration of beauty: a precision study | 35 pages, 5 figures, 7 tables | null | 10.1007/JHEP01(2023)004 | SI-HEP-2022-22 | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We update the Standard Model (SM) predictions for $B$-meson lifetimes within
the heavy quark expansion (HQE). Including for the first time the contribution
of the Darwin operator, SU(3)$_F$ breaking corrections to the matrix element of
dimension-six four-quark operators and the so-called eye-contractions, we
obtain for the total widths $\Gamma (B^+) = (0.58^{+0.11}_{-0.07}) \,
\mbox{ps}^{-1}$, $\Gamma (B_d) = (0.63^{+0.11}_{-0.07}) \, \mbox{ps}^{-1}$,
$\Gamma (B_s) = (0.63^{+0.11}_{-0.07}) \, \mbox{ps}^{-1}$, and for the lifetime
ratios $\tau (B^+) / \tau (B_d) = 1.086 \pm 0.022$, $\tau (B_s) / \tau (B_d) =
1.003 \pm 0.006 \, (1.028 \pm 0.011)$. The two values for the last observable
arise from using two different sets of input for the non-perturbative
parameters $\mu_\pi^2(B_d)$, $\mu_G^2(B_d)$, and $\rho_D^3(B_d)$ as well as
from different estimates of the SU(3)$_F$ breaking in these parameters. Our
results are overall in very good agreement with the corresponding experimental
data, however, there seems to emerge a tension in $\tau (B_s)/\tau (B_d)$ when
considering the second set of input parameters. Specifically, this observable
is extremely sensitive to the size of the parameter $\rho_D^3 (B_d)$ and of the
SU(3)$_F$ breaking effects in $\mu_\pi^2$, $\mu_G^2$ and $\rho_D^3$; hence, it
is of utmost importance to be able to better constrain all these parameters. In
this respect, an extraction of $\mu_\pi^2 (B_s), \mu_G^2 (B_s), \rho_D^3 (B_s)$
from future experimental data on inclusive semileptonic $B_s$-meson decays or
from direct non-perturbative calculations, as well as more insights about the
value of $\rho_D^3 (B)$ extracted from fit, would be very helpful in reducing
the corresponding theory uncertainties.
| [
{
"created": "Thu, 4 Aug 2022 13:21:55 GMT",
"version": "v1"
}
] | 2023-01-25 | [
[
"Lenz",
"Alexander",
""
],
[
"Piscopo",
"Maria Laura",
""
],
[
"Rusov",
"Aleksey V.",
""
]
] | We update the Standard Model (SM) predictions for $B$-meson lifetimes within the heavy quark expansion (HQE). Including for the first time the contribution of the Darwin operator, SU(3)$_F$ breaking corrections to the matrix element of dimension-six four-quark operators and the so-called eye-contractions, we obtain for the total widths $\Gamma (B^+) = (0.58^{+0.11}_{-0.07}) \, \mbox{ps}^{-1}$, $\Gamma (B_d) = (0.63^{+0.11}_{-0.07}) \, \mbox{ps}^{-1}$, $\Gamma (B_s) = (0.63^{+0.11}_{-0.07}) \, \mbox{ps}^{-1}$, and for the lifetime ratios $\tau (B^+) / \tau (B_d) = 1.086 \pm 0.022$, $\tau (B_s) / \tau (B_d) = 1.003 \pm 0.006 \, (1.028 \pm 0.011)$. The two values for the last observable arise from using two different sets of input for the non-perturbative parameters $\mu_\pi^2(B_d)$, $\mu_G^2(B_d)$, and $\rho_D^3(B_d)$ as well as from different estimates of the SU(3)$_F$ breaking in these parameters. Our results are overall in very good agreement with the corresponding experimental data, however, there seems to emerge a tension in $\tau (B_s)/\tau (B_d)$ when considering the second set of input parameters. Specifically, this observable is extremely sensitive to the size of the parameter $\rho_D^3 (B_d)$ and of the SU(3)$_F$ breaking effects in $\mu_\pi^2$, $\mu_G^2$ and $\rho_D^3$; hence, it is of utmost importance to be able to better constrain all these parameters. In this respect, an extraction of $\mu_\pi^2 (B_s), \mu_G^2 (B_s), \rho_D^3 (B_s)$ from future experimental data on inclusive semileptonic $B_s$-meson decays or from direct non-perturbative calculations, as well as more insights about the value of $\rho_D^3 (B)$ extracted from fit, would be very helpful in reducing the corresponding theory uncertainties. |
1703.05273 | Harald Ita | S. Abreu, F. Febres Cordero, H. Ita, M. Jaquier, B. Page and M. Zeng | Two-Loop Four-Gluon Amplitudes with the Numerical Unitarity Method | 6 pages, 3 figures, Mathematica files for reconstructed analytic
formulae | Phys. Rev. Lett. 119, 142001 (2017) | 10.1103/PhysRevLett.119.142001 | FR-PHENO-2017-007, UCLA-17-TEP-103 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the first numerical computation of two-loop amplitudes based on
the unitarity method. As a proof of principle, we compute the four-gluon
process. We discuss the new method, analyze its numerical properties and apply
it to reconstruct the analytic form of the amplitudes. The numerical method is
universal, and can be automated to provide multi-scale two-loop computations
for phenomenologically relevant signatures at hadron colliders.
| [
{
"created": "Wed, 15 Mar 2017 17:22:26 GMT",
"version": "v1"
}
] | 2017-10-11 | [
[
"Abreu",
"S.",
""
],
[
"Cordero",
"F. Febres",
""
],
[
"Ita",
"H.",
""
],
[
"Jaquier",
"M.",
""
],
[
"Page",
"B.",
""
],
[
"Zeng",
"M.",
""
]
] | We present the first numerical computation of two-loop amplitudes based on the unitarity method. As a proof of principle, we compute the four-gluon process. We discuss the new method, analyze its numerical properties and apply it to reconstruct the analytic form of the amplitudes. The numerical method is universal, and can be automated to provide multi-scale two-loop computations for phenomenologically relevant signatures at hadron colliders. |
2301.04407 | Roberto Franceschini | Roberto Franceschini | Beyond-Standard-Model Physics Associated with the Top Quark | 25 pages, 4 figures; Invited review prepared for Annual Review of
Nuclear and Particle Science 73 (2023) | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We review scenarios of physics beyond the Standard Model in which the top
quark plays a special role. Models that aim at the stabilization of the weak
scale are presented together with the specific phenomenology of partner states
that are characteristic of this type of model. Further, we present models of
flavor in which the top quark is singled out as a special flavor among the SM
ones. The flavor and collider phenomenology of these models is broadly
presented. Finally, we discuss the possibility that dark matter interacts
preferably with the top quark flavor and broadly present the dark matter
phenomenology of these scenarios, as well as collider and flavor signals.
| [
{
"created": "Wed, 11 Jan 2023 11:18:45 GMT",
"version": "v1"
}
] | 2023-01-12 | [
[
"Franceschini",
"Roberto",
""
]
] | We review scenarios of physics beyond the Standard Model in which the top quark plays a special role. Models that aim at the stabilization of the weak scale are presented together with the specific phenomenology of partner states that are characteristic of this type of model. Further, we present models of flavor in which the top quark is singled out as a special flavor among the SM ones. The flavor and collider phenomenology of these models is broadly presented. Finally, we discuss the possibility that dark matter interacts preferably with the top quark flavor and broadly present the dark matter phenomenology of these scenarios, as well as collider and flavor signals. |
1703.02190 | Kazuhiro Tanaka | Kazuhiro Tanaka (Juntendo Univ.) | QCD mechanisms for accessing the nucleon GPDs with the exclusive
pion-induced Drell-Yan process at J-PARC | 6 pages, 5 figures. To appear in proceedings of 22nd International
Symposium on Spin Physics (SPIN 2016), University of Illinois, Champaign,
Illinois, USA, September 25-30, 2016 | null | null | J-PARC-TH-0087 | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Generalized parton distributions (GPDs) encoding multidimensional information
of hadron partonic structure appear as the building blocks in a factorized
description of hard exclusive reactions. The nucleon GPDs have been accessed by
deeply virtual Compton scattering and deeply virtual meson production with
lepton beam. A complementary probe with hadron beam is the exclusive
pion-induced Drell-Yan process. We discuss recent theoretical advances on
describing this process in terms of the partonic subprocess convoluted with the
nucleon GPDs and the pion distribution amplitudes. Furthermore, we mention the
feasibility study for measuring the exclusive pion-induced Drell-Yan process,
$\pi^- p \to \mu^+ \mu^- n$, via a spectrometer at the High Momentum Beamline
being constructed at J-PARC in Japan. We also point out the possible soft
partonic mechanisms beyond the QCD factorization framework, which could give
important contributions at J-PARC kinematics, and present an estimate of the
soft mechanisms making use of dispersion relations and quark-hadron duality.
Realization of the measurement of the exclusive pion-induced Drell-Yan process
at J-PARC will provide a new test of QCD descriptions of a novel class of hard
exclusive reactions. It will also offer the possibility of experimentally
accessing nucleon GPDs at large timelike virtuality.
| [
{
"created": "Tue, 7 Mar 2017 03:05:27 GMT",
"version": "v1"
}
] | 2017-03-08 | [
[
"Tanaka",
"Kazuhiro",
"",
"Juntendo Univ."
]
] | Generalized parton distributions (GPDs) encoding multidimensional information of hadron partonic structure appear as the building blocks in a factorized description of hard exclusive reactions. The nucleon GPDs have been accessed by deeply virtual Compton scattering and deeply virtual meson production with lepton beam. A complementary probe with hadron beam is the exclusive pion-induced Drell-Yan process. We discuss recent theoretical advances on describing this process in terms of the partonic subprocess convoluted with the nucleon GPDs and the pion distribution amplitudes. Furthermore, we mention the feasibility study for measuring the exclusive pion-induced Drell-Yan process, $\pi^- p \to \mu^+ \mu^- n$, via a spectrometer at the High Momentum Beamline being constructed at J-PARC in Japan. We also point out the possible soft partonic mechanisms beyond the QCD factorization framework, which could give important contributions at J-PARC kinematics, and present an estimate of the soft mechanisms making use of dispersion relations and quark-hadron duality. Realization of the measurement of the exclusive pion-induced Drell-Yan process at J-PARC will provide a new test of QCD descriptions of a novel class of hard exclusive reactions. It will also offer the possibility of experimentally accessing nucleon GPDs at large timelike virtuality. |
hep-ph/9212240 | Bludman | Sidney A. Bludman | Cosmological and Astrophysical Bounds on Neutrino Masses and Lifetimes | 4 pages, Latex | null | null | UPR-530-T | hep-ph | null | The best upper bounds on the masses of stable and unstable light neutrinos
derive from the upper bound on the total mass density, as inferred from the
lower limit $t_0> 13$ Gyr on the dynamical age of the Universe: If the Universe
is matter-dominated, $m_\nu<35(23)\times$ max$ [1, (t_0/\tau_\nu)^{1/2}]$ eV,
according as a cosmological constant is (is not) allowed. The best constraints
on the radiative decay of light neutrinos derive from the failure to observe
prompt gamma rays accompanying the neutrinos from Supernova 1987A: For any
$m_{\nu} > 630$ eV, this provides a stronger bound on the neutrino transition
moment than that obtained from red giants or white dwarfs. For $m_\nu > 250$ eV
or $\tau_\nu < t_{rec}\sim 7\times 10^{12}$ sec, the upper limit on the
radiative branching ratio is even smaller than that obtained from the limits on
$\mu$-distortion of the cosmic background radiation. Our results improve on
earlier cosmological and radiative decay constraints by an overall factor
twenty, and allow neutrinos more massive than 35 eV, only if they decay
overwhelmingly into singlet majorons or other new particles.
| [
{
"created": "Tue, 8 Dec 1992 23:18:45 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bludman",
"Sidney A.",
""
]
] | The best upper bounds on the masses of stable and unstable light neutrinos derive from the upper bound on the total mass density, as inferred from the lower limit $t_0> 13$ Gyr on the dynamical age of the Universe: If the Universe is matter-dominated, $m_\nu<35(23)\times$ max$ [1, (t_0/\tau_\nu)^{1/2}]$ eV, according as a cosmological constant is (is not) allowed. The best constraints on the radiative decay of light neutrinos derive from the failure to observe prompt gamma rays accompanying the neutrinos from Supernova 1987A: For any $m_{\nu} > 630$ eV, this provides a stronger bound on the neutrino transition moment than that obtained from red giants or white dwarfs. For $m_\nu > 250$ eV or $\tau_\nu < t_{rec}\sim 7\times 10^{12}$ sec, the upper limit on the radiative branching ratio is even smaller than that obtained from the limits on $\mu$-distortion of the cosmic background radiation. Our results improve on earlier cosmological and radiative decay constraints by an overall factor twenty, and allow neutrinos more massive than 35 eV, only if they decay overwhelmingly into singlet majorons or other new particles. |
hep-ph/0508109 | Rabindra N. Mohapatra | R.N. Mohapatra and S. Nasri and S. Nussinov | Some Implications of Neutron Mirror Neutron Oscillation | 12 pages, 2 figures; minor changes in the text; accepted for
publication in Phys. Lett.B | Phys.Lett.B627:124-130,2005 | 10.1016/j.physletb.2005.08.101 | UMD-PP-05-051 | hep-ph | null | We comment on a recently discussed possibility of oscillations between
neutrons and degenerate mirror neutrons in the context of mirror models for
particles and forces. It has been noted by Bento and Berezhiani that if these
oscillations occurred at a rate of $\tau^{-1}_{NN'}\sim sec^{-1}$, it would
help explain putative super GKZ cosmic ray events provided the temperature of
the mirror radiation is $\sim 0.3-0.4$ times that of familiar cosmic microwave
background radiation. We discuss how such oscillation time scales can be
realized in mirror models and find that the simplest nonsupersymmetric model
for this idea requires the existence of a low mass (30-3000 GeV) color triplet
scalar or vector boson. A supersymmetric model, where this constraint can be
avoided is severely constrained by the requirement of maintaining a cooler
mirror sector. We also find that the reheat temperature after inflation in
generic models that give fast $n-n'$ oscillation be less than about 300 GeV in
order to maintain the required relative coolness of the mirror sector.
| [
{
"created": "Tue, 9 Aug 2005 18:17:42 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Aug 2005 18:29:28 GMT",
"version": "v2"
}
] | 2014-11-18 | [
[
"Mohapatra",
"R. N.",
""
],
[
"Nasri",
"S.",
""
],
[
"Nussinov",
"S.",
""
]
] | We comment on a recently discussed possibility of oscillations between neutrons and degenerate mirror neutrons in the context of mirror models for particles and forces. It has been noted by Bento and Berezhiani that if these oscillations occurred at a rate of $\tau^{-1}_{NN'}\sim sec^{-1}$, it would help explain putative super GKZ cosmic ray events provided the temperature of the mirror radiation is $\sim 0.3-0.4$ times that of familiar cosmic microwave background radiation. We discuss how such oscillation time scales can be realized in mirror models and find that the simplest nonsupersymmetric model for this idea requires the existence of a low mass (30-3000 GeV) color triplet scalar or vector boson. A supersymmetric model, where this constraint can be avoided is severely constrained by the requirement of maintaining a cooler mirror sector. We also find that the reheat temperature after inflation in generic models that give fast $n-n'$ oscillation be less than about 300 GeV in order to maintain the required relative coolness of the mirror sector. |
hep-ph/0212077 | Bojan Golli | B. Golli, W. Broniowski, G. Ripka | Baryons as Solitons in Chiral Quark Models | Invited talk at the XVIII European Conference on Few-Body Problems in
Physics, September 8-14, Bled, Slovenia, to be published in Few-Body Systems,
Supplement, 6 pages LaTeX | Few Body Syst.Suppl. 14 (2003) 1-6 | null | null | hep-ph | null | We describe the formation of solitons in NJL-type models and discuss the
influence of the regularization scheme on the stability of the solution. We
concentrate on models with non-local regulators in which stable solutions exist
without introducing additional constraints.
| [
{
"created": "Thu, 5 Dec 2002 08:04:02 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Golli",
"B.",
""
],
[
"Broniowski",
"W.",
""
],
[
"Ripka",
"G.",
""
]
] | We describe the formation of solitons in NJL-type models and discuss the influence of the regularization scheme on the stability of the solution. We concentrate on models with non-local regulators in which stable solutions exist without introducing additional constraints. |
0812.3622 | Fedor Bezrukov | F. Bezrukov, D. Gorbunov, M. Shaposhnikov | On initial conditions for the Hot Big Bang | 41 pages, 5 figures. Journal version accepted in JCAP | JCAP 0906:029,2009 | 10.1088/1475-7516/2009/06/029 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyse the process of reheating the Universe in the electroweak theory
where the Higgs field plays a role of the inflaton. We estimate the maximal
temperature of the Universe and fix the initial conditions for
radiation-dominated phase of the Universe expansion in the framework of the
Standard Model (SM) and of the nuMSM -- the minimal extension of the SM by
three right-handed singlet fermions. We show that the inflationary epoch is
followed by a matter dominated stage related to the Higgs field oscillations.
We investigate the energy transfer from Higgs-inflaton to the SM particles and
show that the radiation dominated phase of the Universe expansion starts at
temperature T_r~(3-15)*10^{13} GeV, where the upper bound depends on the Higgs
boson mass. We estimate the production rate of singlet fermions at preheating
and find that their concentrations at T_r are negligibly small. This suggests
that the sterile neutrino Dark Matter (DM) production and baryogenesis in the
nuMSM with Higgs-driven inflation are low energy phenomena, having nothing to
do with inflation. We study then a modification of the nuMSM, adding to its
Lagrangian higher dimensional operators suppressed by the Planck scale. The
role of these operators in Higgs-driven inflation is clarified. We find that
these operators do not contribute to the production of Warm Dark Matter (WDM)
and to baryogenesis. We also demonstrate that the sterile neutrino with mass
exceeding 100 keV (a Cold Dark Matter (CDM) candidate) can be created during
the reheating stage of the Universe in necessary amounts. We argue that the
mass of DM sterile neutrino should not exceed few MeV in order not to overclose
the Universe.
| [
{
"created": "Thu, 18 Dec 2008 19:04:35 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Jun 2009 14:30:30 GMT",
"version": "v2"
}
] | 2010-04-14 | [
[
"Bezrukov",
"F.",
""
],
[
"Gorbunov",
"D.",
""
],
[
"Shaposhnikov",
"M.",
""
]
] | We analyse the process of reheating the Universe in the electroweak theory where the Higgs field plays a role of the inflaton. We estimate the maximal temperature of the Universe and fix the initial conditions for radiation-dominated phase of the Universe expansion in the framework of the Standard Model (SM) and of the nuMSM -- the minimal extension of the SM by three right-handed singlet fermions. We show that the inflationary epoch is followed by a matter dominated stage related to the Higgs field oscillations. We investigate the energy transfer from Higgs-inflaton to the SM particles and show that the radiation dominated phase of the Universe expansion starts at temperature T_r~(3-15)*10^{13} GeV, where the upper bound depends on the Higgs boson mass. We estimate the production rate of singlet fermions at preheating and find that their concentrations at T_r are negligibly small. This suggests that the sterile neutrino Dark Matter (DM) production and baryogenesis in the nuMSM with Higgs-driven inflation are low energy phenomena, having nothing to do with inflation. We study then a modification of the nuMSM, adding to its Lagrangian higher dimensional operators suppressed by the Planck scale. The role of these operators in Higgs-driven inflation is clarified. We find that these operators do not contribute to the production of Warm Dark Matter (WDM) and to baryogenesis. We also demonstrate that the sterile neutrino with mass exceeding 100 keV (a Cold Dark Matter (CDM) candidate) can be created during the reheating stage of the Universe in necessary amounts. We argue that the mass of DM sterile neutrino should not exceed few MeV in order not to overclose the Universe. |
1312.1802 | Sunghoon Jung | Sunghoon Jung, James D. Wells | Gaugino physics of split supersymmetry spectrum at the LHC and future
proton colliders | 9 pages, 5 figures | Phys. Rev. D 89, 075004 (2014) | 10.1103/PhysRevD.89.075004 | KIAS-P13064 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Discovery of the Higgs boson and lack of discovery of superpartners in the
first run at LHC are both predictions of split supersymmetry with thermal dark
matter. We discuss what it would take to find gluinos at hadron supercolliders,
including the LHC at 14 TeV center of mass energy, and future pp colliders at
100 TeV and 200 TeV. We generalize the discussion by re-expressing the search
capacity in terms of gluino to lightest superpartner mass ratio, and apply
results to other scenarios, such as gauge mediation and mirage mediation.
| [
{
"created": "Fri, 6 Dec 2013 08:38:40 GMT",
"version": "v1"
}
] | 2014-04-23 | [
[
"Jung",
"Sunghoon",
""
],
[
"Wells",
"James D.",
""
]
] | Discovery of the Higgs boson and lack of discovery of superpartners in the first run at LHC are both predictions of split supersymmetry with thermal dark matter. We discuss what it would take to find gluinos at hadron supercolliders, including the LHC at 14 TeV center of mass energy, and future pp colliders at 100 TeV and 200 TeV. We generalize the discussion by re-expressing the search capacity in terms of gluino to lightest superpartner mass ratio, and apply results to other scenarios, such as gauge mediation and mirage mediation. |
1807.05508 | Mubarak Alqahtani | Mubarak Alqahtani, Dekrayat Almaalol, Mohammad Nopoush, Radoslaw
Ryblewski, and Michael Strickland | Anisotropic hydrodynamic modeling of heavy-ion collisions at LHC and
RHIC | 4 pages, 3 figures. Quark Matter 2018 proceedings | null | 10.1016/j.nuclphysa.2018.10.066 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this proceedings contribution, we review 3+1d quasiparticle anisotropic
hydrodynamics (aHydroQP). Then, we show some recent phenomenological
comparisons between the aHydroQP model and some experimental results. We show
comparisons between aHydroQP and Pb-Pb 2.76 TeV collisions from the ALICE
collaboration and Au-Au 200 GeV collisions from RHIC experiments. We show that
the quasiparticle anisotropic hydrodynamics model is able to describe the
experimental results for Pb-Pb and Au-Au collisions quite well for many
observables such as the spectra, multiplicity, elliptic flow, and HBT radii in
many centrality classes.
| [
{
"created": "Sun, 15 Jul 2018 08:07:42 GMT",
"version": "v1"
}
] | 2019-02-20 | [
[
"Alqahtani",
"Mubarak",
""
],
[
"Almaalol",
"Dekrayat",
""
],
[
"Nopoush",
"Mohammad",
""
],
[
"Ryblewski",
"Radoslaw",
""
],
[
"Strickland",
"Michael",
""
]
] | In this proceedings contribution, we review 3+1d quasiparticle anisotropic hydrodynamics (aHydroQP). Then, we show some recent phenomenological comparisons between the aHydroQP model and some experimental results. We show comparisons between aHydroQP and Pb-Pb 2.76 TeV collisions from the ALICE collaboration and Au-Au 200 GeV collisions from RHIC experiments. We show that the quasiparticle anisotropic hydrodynamics model is able to describe the experimental results for Pb-Pb and Au-Au collisions quite well for many observables such as the spectra, multiplicity, elliptic flow, and HBT radii in many centrality classes. |
hep-ph/0608057 | Nikolas Kauer | T. Binoth (Edinburgh U.), S. Karg, N. Kauer, R. R\"uckl (Wurzburg U.) | Multi-Higgs boson production in the Standard Model and beyond | 17 pages, 17 figures | Phys.Rev.D74:113008,2006 | 10.1103/PhysRevD.74.113008 | Edinburgh 2006/15 | hep-ph | null | We present a calculation of the loop-induced processes gg -> HH and gg ->
HHH, and investigate the observability of multi-Higgs boson production at the
CERN Large Hadron Collider (LHC) in the Standard Model (SM) and beyond. While
the SM cross sections are too small to allow observation at the LHC, we
demonstrate that physics beyond the SM can lead to amplified, observable cross
sections. Furthermore, the applicability of the heavy top quark approximation
in two- and three-Higgs boson production is investigated. We conclude that
multi-Higgs boson production at the SuperLHC is an interesting probe of Higgs
sectors beyond the SM and warrants further study.
| [
{
"created": "Fri, 4 Aug 2006 19:01:57 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Dec 2006 12:35:06 GMT",
"version": "v2"
}
] | 2011-01-13 | [
[
"Binoth",
"T.",
"",
"Edinburgh U."
],
[
"Karg",
"S.",
"",
"Wurzburg U."
],
[
"Kauer",
"N.",
"",
"Wurzburg U."
],
[
"Rückl",
"R.",
"",
"Wurzburg U."
]
] | We present a calculation of the loop-induced processes gg -> HH and gg -> HHH, and investigate the observability of multi-Higgs boson production at the CERN Large Hadron Collider (LHC) in the Standard Model (SM) and beyond. While the SM cross sections are too small to allow observation at the LHC, we demonstrate that physics beyond the SM can lead to amplified, observable cross sections. Furthermore, the applicability of the heavy top quark approximation in two- and three-Higgs boson production is investigated. We conclude that multi-Higgs boson production at the SuperLHC is an interesting probe of Higgs sectors beyond the SM and warrants further study. |
1611.00474 | Qin-Tao Song | S. Kumano and Qin-Tao Song | Estimate on Spin Asymmetry for Drell-Yan Process at Fermilab with
Tensor-Polarized Deuteron | 4 pages, 3 eps figures, to be published in JPS Conf. Proc.,
Proceedings of the 14th International Conference on Meson-Nucleon Physics and
the Structure of the Nucleon (MENU2016), July 25-30, 2016, Kyoto, Japan | null | 10.7566/JPSCP.13.020048 | KEK-TH-1931, J-PARC-TH-0066 | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There are four new structure functions for the spin-1 deuteron in comparison
with the ones for the spin-1/2 proton, and they are called $b_1$, $b_2$, $b_3$,
and $b_4$. The twist-2 structure functions $b_1$ and $b_2$ are expressed by
tensor-polarized parton distribution functions in the deuteron. HERMES
measurements of $b_1$ are much different from the prediction of the standard
deuteron model with D-state admixture. It indicates that the structure
functions $b_1$ and $b_2$ probe an interesting new aspect in the deuteron.
There is an approved experiment at JLab to measure $b_1$ and it is expected to
start in 2019. On the other hand, the measurement of tensor-polarized
distributions is under consideration at Fermilab by the Drell-Yan process with
the unpolarized proton beam and tensor-polarized deuteron target. It is
expected to provide crucial information on tensor-polarized antiquark
distributions. Since the distributions are small quantities, it is important to
estimate the tensor-polarized spin asymmetry theoretically to find experimental
feasibility for an actual proposal at Fermilab.
| [
{
"created": "Wed, 2 Nov 2016 05:30:47 GMT",
"version": "v1"
}
] | 2017-03-08 | [
[
"Kumano",
"S.",
""
],
[
"Song",
"Qin-Tao",
""
]
] | There are four new structure functions for the spin-1 deuteron in comparison with the ones for the spin-1/2 proton, and they are called $b_1$, $b_2$, $b_3$, and $b_4$. The twist-2 structure functions $b_1$ and $b_2$ are expressed by tensor-polarized parton distribution functions in the deuteron. HERMES measurements of $b_1$ are much different from the prediction of the standard deuteron model with D-state admixture. It indicates that the structure functions $b_1$ and $b_2$ probe an interesting new aspect in the deuteron. There is an approved experiment at JLab to measure $b_1$ and it is expected to start in 2019. On the other hand, the measurement of tensor-polarized distributions is under consideration at Fermilab by the Drell-Yan process with the unpolarized proton beam and tensor-polarized deuteron target. It is expected to provide crucial information on tensor-polarized antiquark distributions. Since the distributions are small quantities, it is important to estimate the tensor-polarized spin asymmetry theoretically to find experimental feasibility for an actual proposal at Fermilab. |
hep-ph/0401208 | Alejandro Gutierrez | A. Gutierrez-Rodriguez (Zacatecas University, Mexico), M. A.
Hernandez-Ruiz (Zacatecas University, Mexico) and A. Del Rio-De Santiago
(Zacatecas University, Mexico) | Bounds on the magnetic moment and electric dipole moment of the
$\tau$-neutrino via the process $e^{+}e^{-}\to \nu \bar \nu \gamma$ | 17 pages, 2 figures. Accepted for publication in Phys. Rev. D | Phys.Rev. D69 (2004) 073008 | 10.1103/PhysRevD.69.073008 | null | hep-ph | null | Bounds on the anomalous magnetic moment and the electric dipole moment of the
$\tau$-neutrino are calculated through the reaction $e^{+}e^{-}\to \nu \bar \nu
\gamma$ at the $Z_1$-pole, and in the framework of a left-right symmetric
model. The results are based on the recent data reported by the L3
Collaboration at CERN LEP. We find that the bounds are almost independent of
the mixing angle $\phi$ of the model in the allowed experimental range for this
parameter. In addition, the analytical and numerical results for the
cross-section have never been reported in the literature before.
| [
{
"created": "Mon, 26 Jan 2004 19:18:32 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Jan 2004 19:15:59 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Gutierrez-Rodriguez",
"A.",
"",
"Zacatecas University, Mexico"
],
[
"Hernandez-Ruiz",
"M. A.",
"",
"Zacatecas University, Mexico"
],
[
"Santiago",
"A. Del Rio-De",
"",
"Zacatecas University, Mexico"
]
] | Bounds on the anomalous magnetic moment and the electric dipole moment of the $\tau$-neutrino are calculated through the reaction $e^{+}e^{-}\to \nu \bar \nu \gamma$ at the $Z_1$-pole, and in the framework of a left-right symmetric model. The results are based on the recent data reported by the L3 Collaboration at CERN LEP. We find that the bounds are almost independent of the mixing angle $\phi$ of the model in the allowed experimental range for this parameter. In addition, the analytical and numerical results for the cross-section have never been reported in the literature before. |
1812.08270 | Riccardo Catena | Anton B\"ackstr\"om, Riccardo Catena and Carlos P\'erez de los Heros | Assessing the sensitivity of PINGU to effective dark matter-nucleon
interactions | 20 pages, 6 figures and 1 table | null | 10.1088/1475-7516/2019/05/023 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the sensitivity of next generation neutrino telescopes to the 28
(isoscalar and isovector) coupling constants defining the non-relativistic
effective theory of (spin 1/2) dark matter (DM)-nucleon interactions. We take
as a benchmark detector the proposed Precision IceCube Next Generation Upgrade
(PINGU), although our results are valid for any other neutrino telescope of
similar effective volume. We express PINGU's sensitivity in terms of $5\sigma$
sensitivity contours in the DM-mass - coupling constant plane, and compare our
sensitivity contours with the 90% C.L. exclusion limits on the same coupling
constants that we obtain from a reanalysis of the null result of current DM
searches at IceCube/DeepCore. We find that PINGU can effectively probe not only
the canonical spin-independent and spin-dependent DM-nucleon interactions, but
also velocity-dependent or momentum-dependent interactions that generate
coherently enhanced DM-nucleus scattering cross sections. We also find that
PINGU's $5\sigma$ sensitivity contours are significantly below current
IceCube/DeepCore 90% C.L. exclusion limits when $b\bar{b}$ is the leading DM
annihilation channel. This result shows the importance of lowering the
experimental energy threshold when probing models that generate soft neutrino
energy spectra, and holds true independently of the assumed DM-nucleon
interaction and for all DM masses tested here. When DM primarily annihilates
into $\tau\bar{\tau}$, a PINGU-like detector will improve upon current
exclusion limits for DM masses below $35$ GeV, independently of the assumed
DM-nucleon interaction.
| [
{
"created": "Wed, 19 Dec 2018 22:16:49 GMT",
"version": "v1"
}
] | 2019-05-29 | [
[
"Bäckström",
"Anton",
""
],
[
"Catena",
"Riccardo",
""
],
[
"Heros",
"Carlos Pérez de los",
""
]
] | We calculate the sensitivity of next generation neutrino telescopes to the 28 (isoscalar and isovector) coupling constants defining the non-relativistic effective theory of (spin 1/2) dark matter (DM)-nucleon interactions. We take as a benchmark detector the proposed Precision IceCube Next Generation Upgrade (PINGU), although our results are valid for any other neutrino telescope of similar effective volume. We express PINGU's sensitivity in terms of $5\sigma$ sensitivity contours in the DM-mass - coupling constant plane, and compare our sensitivity contours with the 90% C.L. exclusion limits on the same coupling constants that we obtain from a reanalysis of the null result of current DM searches at IceCube/DeepCore. We find that PINGU can effectively probe not only the canonical spin-independent and spin-dependent DM-nucleon interactions, but also velocity-dependent or momentum-dependent interactions that generate coherently enhanced DM-nucleus scattering cross sections. We also find that PINGU's $5\sigma$ sensitivity contours are significantly below current IceCube/DeepCore 90% C.L. exclusion limits when $b\bar{b}$ is the leading DM annihilation channel. This result shows the importance of lowering the experimental energy threshold when probing models that generate soft neutrino energy spectra, and holds true independently of the assumed DM-nucleon interaction and for all DM masses tested here. When DM primarily annihilates into $\tau\bar{\tau}$, a PINGU-like detector will improve upon current exclusion limits for DM masses below $35$ GeV, independently of the assumed DM-nucleon interaction. |
1512.06727 | Constantin Sluka | Stefan Antusch, Constantin Sluka | Predicting the Sparticle Spectrum from GUTs via SUSY Threshold
Corrections with SusyTC | 54 pages, 12 figures. SusyTC can be downloaded from
http://particlesandcosmology.unibas.ch/pages/SusyTC.htm | null | 10.1007/JHEP07(2016)108 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Grand Unified Theories (GUTs) can feature predictions for the ratios of quark
and lepton Yukawa couplings at high energy, which can be tested with the
increasingly precise results for the fermion masses, given at low energies. To
perform such tests, the renormalization group (RG) running has to be performed
with sufficient accuracy. In supersymmetric (SUSY) theories, the one-loop
threshold corrections (TC) are of particular importance and, since they affect
the quark-lepton mass relations, link a given GUT flavour model to the
sparticle spectrum. To accurately study such predictions, we extend and
generalize various formulas in the literature which are needed for a precision
analysis of SUSY flavour GUT models. We introduce the new software tool SusyTC,
a major extension to the Mathematica package REAP, where these formulas are
implemented. SusyTC extends the functionality of REAP by a full inclusion of
the (complex) MSSM SUSY sector and a careful calculation of the one-loop SUSY
threshold corrections for the full down-type quark, up-type quark and charged
lepton Yukawa coupling matrices in the electroweak-unbroken phase. Among other
useful features, SusyTC calculates the one-loop corrected pole mass of the
charged (or the CP-odd) Higgs boson as well as provides output in SLHA
conventions, i.e. the necessary input for external software, e.g. for
performing a two-loop Higgs mass calculation. We apply SusyTC to study the
predictions for the parameters of the CMSSM (mSUGRA) SUSY scenario from the set
of GUT scale Yukawa relations $y_e / y_d = - 1/2$, $y_\mu / y_s = 6$, and
$y_\tau / y_b = - 3/2$, which has been proposed recently in the context of SUSY
GUT flavour models.
| [
{
"created": "Mon, 21 Dec 2015 17:44:48 GMT",
"version": "v1"
}
] | 2016-08-24 | [
[
"Antusch",
"Stefan",
""
],
[
"Sluka",
"Constantin",
""
]
] | Grand Unified Theories (GUTs) can feature predictions for the ratios of quark and lepton Yukawa couplings at high energy, which can be tested with the increasingly precise results for the fermion masses, given at low energies. To perform such tests, the renormalization group (RG) running has to be performed with sufficient accuracy. In supersymmetric (SUSY) theories, the one-loop threshold corrections (TC) are of particular importance and, since they affect the quark-lepton mass relations, link a given GUT flavour model to the sparticle spectrum. To accurately study such predictions, we extend and generalize various formulas in the literature which are needed for a precision analysis of SUSY flavour GUT models. We introduce the new software tool SusyTC, a major extension to the Mathematica package REAP, where these formulas are implemented. SusyTC extends the functionality of REAP by a full inclusion of the (complex) MSSM SUSY sector and a careful calculation of the one-loop SUSY threshold corrections for the full down-type quark, up-type quark and charged lepton Yukawa coupling matrices in the electroweak-unbroken phase. Among other useful features, SusyTC calculates the one-loop corrected pole mass of the charged (or the CP-odd) Higgs boson as well as provides output in SLHA conventions, i.e. the necessary input for external software, e.g. for performing a two-loop Higgs mass calculation. We apply SusyTC to study the predictions for the parameters of the CMSSM (mSUGRA) SUSY scenario from the set of GUT scale Yukawa relations $y_e / y_d = - 1/2$, $y_\mu / y_s = 6$, and $y_\tau / y_b = - 3/2$, which has been proposed recently in the context of SUSY GUT flavour models. |
1108.3794 | Liam Keegan | Simon Catterall, Luigi Del Debbio, Joel Giedt, Liam Keegan | MCRG Minimal Walking Technicolor | 30 pages, 30 figures | null | 10.1103/PhysRevD.85.094501 | Edinburgh 2011/23 | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a Monte Carlo renormalisation group study of the SU(2) gauge
theory with two Dirac fermions in the adjoint representation. Using the
two-lattice matching technique we measure the running of the coupling and the
anomalous mass dimension. We find slow running of the coupling, compatible with
an infrared fixed point. Assuming this running is negligible we find a
vanishing anomalous dimension, gamma=-0.03(13), however taking this source of
systematic error into account gives a much larger range of allowed values, -0.6
< gamma < 0.6. We also attempt to measure the anomalous mass dimension using
the stability matrix method. We discuss the systematic errors affecting the
current analysis and possible improvements.
| [
{
"created": "Thu, 18 Aug 2011 16:54:21 GMT",
"version": "v1"
}
] | 2013-05-30 | [
[
"Catterall",
"Simon",
""
],
[
"Del Debbio",
"Luigi",
""
],
[
"Giedt",
"Joel",
""
],
[
"Keegan",
"Liam",
""
]
] | We present a Monte Carlo renormalisation group study of the SU(2) gauge theory with two Dirac fermions in the adjoint representation. Using the two-lattice matching technique we measure the running of the coupling and the anomalous mass dimension. We find slow running of the coupling, compatible with an infrared fixed point. Assuming this running is negligible we find a vanishing anomalous dimension, gamma=-0.03(13), however taking this source of systematic error into account gives a much larger range of allowed values, -0.6 < gamma < 0.6. We also attempt to measure the anomalous mass dimension using the stability matrix method. We discuss the systematic errors affecting the current analysis and possible improvements. |
hep-ph/0410205 | Alexander D. Mitov | Alexander Mitov | Perturbative Heavy Quark Fragmentation Function through O(\alpha_s^2):
Gluon Initiated Contribution | 8 pages, 1 figure; minor clarifications in the text; references added | Phys.Rev.D71:054021,2005 | 10.1103/PhysRevD.71.054021 | UH-511-1059-2004 | hep-ph | null | We derive the gluon initiated contribution to the initial condition for the
perturbative fragmentation function of a heavy quark through order
O(\alpha_s^2) in the MS-bar scheme. This result is needed for the resummation
with next-to-next-to-leading logarithmic accuracy of quasi-collinear logarithms
ln^k(m^2) in heavy quark differential distributions by solving the complete
DGLAP equation. Together with the previously evaluated fermion initiated
components, this result completes the derivation of the initial condition for
the perturbative fragmentation function at next-to-next-to-leading order.
| [
{
"created": "Thu, 14 Oct 2004 10:23:18 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Jul 2005 00:26:25 GMT",
"version": "v2"
}
] | 2014-11-18 | [
[
"Mitov",
"Alexander",
""
]
] | We derive the gluon initiated contribution to the initial condition for the perturbative fragmentation function of a heavy quark through order O(\alpha_s^2) in the MS-bar scheme. This result is needed for the resummation with next-to-next-to-leading logarithmic accuracy of quasi-collinear logarithms ln^k(m^2) in heavy quark differential distributions by solving the complete DGLAP equation. Together with the previously evaluated fermion initiated components, this result completes the derivation of the initial condition for the perturbative fragmentation function at next-to-next-to-leading order. |
hep-ph/0510344 | Eduardo Souza Fraga | Eduardo S. Fraga | The role of noise and dissipation in the hadronization of the
quark-gluon plasma | 8 pages, invited talk at the Workshop on Quark Gluon Plasma
Thermalization, Vienna, August 10-12, 2005 | Eur.Phys.J. A29 (2006) 123-126 | 10.1140/epja/i2005-10310-1 | null | hep-ph cond-mat.stat-mech nucl-th | null | We discuss the role of noise and dissipation in the explosive spinodal
decomposition scenario of hadron production during the chiral transition after
a high-energy heavy ion collision. We use a Langevin description inspired by
nonequilibrium field theory to perform real-time lattice simulations of the
behavior of the chiral fields. Preliminary results for the interplay between
additive and multiplicative noise terms, as well as for non-Markovian
corrections, are also presented.
| [
{
"created": "Wed, 26 Oct 2005 16:10:10 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Fraga",
"Eduardo S.",
""
]
] | We discuss the role of noise and dissipation in the explosive spinodal decomposition scenario of hadron production during the chiral transition after a high-energy heavy ion collision. We use a Langevin description inspired by nonequilibrium field theory to perform real-time lattice simulations of the behavior of the chiral fields. Preliminary results for the interplay between additive and multiplicative noise terms, as well as for non-Markovian corrections, are also presented. |
2012.01688 | Hiroshi Okada | Hiroshi Okada, Morimitsu Tanimoto | Spontaneous CP violation by modulus $\tau$ in $A_4$ model of lepton
flavors | 24 pages, 12 figures, 3 tables. arXiv admin note: text overlap with
arXiv:2009.14242 | null | 10.1007/JHEP03(2021)010 | APCTP Pre2020-033 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We discuss the modular $A_4$ invariant model of leptons combining with the
generalized CP symmetry. In our model, both CP and modular symmetries are
broken spontaneously by the vacuum expectation value of the modulus $\tau$. The
source of the CP violation is a non-trivial value of ${\rm Re} [\tau]$ while
other parameters of the model are real. The allowed region of $\tau$ is in very
narrow one close to the fixed point $\tau=i$ for both normal hierarchy (NH) and
inverted ones (IH) of neutrino masses. The CP violating Dirac phase
$\delta_{CP}$ is predicted clearly in $[98^\circ,\,110^\circ]$ and
$[250^\circ,\,262^\circ]$ for NH at $3\,\sigma$ confidence level. On the other
hand, $\delta_{CP}$ is in $[95^\circ,100^\circ]$ and $[260^\circ,\,265^\circ]$
for IH at $5\,\sigma$ confidence level. The predicted $\sum m_i$ is in
$[82,\,102]$ meV for NH and $\sum m_i=[134,\,180]$ meV for IH. The effective
mass $\langle m_{ee}\rangle$ for the $0\nu\beta\beta$ decay is predicted in
$[12.5,\,20.5]$ meV and $[54,\,67]$ meV for NH and IH, respectively.
| [
{
"created": "Thu, 3 Dec 2020 03:50:20 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Jan 2021 11:28:51 GMT",
"version": "v2"
}
] | 2021-03-17 | [
[
"Okada",
"Hiroshi",
""
],
[
"Tanimoto",
"Morimitsu",
""
]
] | We discuss the modular $A_4$ invariant model of leptons combining with the generalized CP symmetry. In our model, both CP and modular symmetries are broken spontaneously by the vacuum expectation value of the modulus $\tau$. The source of the CP violation is a non-trivial value of ${\rm Re} [\tau]$ while other parameters of the model are real. The allowed region of $\tau$ is in very narrow one close to the fixed point $\tau=i$ for both normal hierarchy (NH) and inverted ones (IH) of neutrino masses. The CP violating Dirac phase $\delta_{CP}$ is predicted clearly in $[98^\circ,\,110^\circ]$ and $[250^\circ,\,262^\circ]$ for NH at $3\,\sigma$ confidence level. On the other hand, $\delta_{CP}$ is in $[95^\circ,100^\circ]$ and $[260^\circ,\,265^\circ]$ for IH at $5\,\sigma$ confidence level. The predicted $\sum m_i$ is in $[82,\,102]$ meV for NH and $\sum m_i=[134,\,180]$ meV for IH. The effective mass $\langle m_{ee}\rangle$ for the $0\nu\beta\beta$ decay is predicted in $[12.5,\,20.5]$ meV and $[54,\,67]$ meV for NH and IH, respectively. |
1901.04526 | Mar\'ia Luisa L\'opez Ib\'a\~nez | M.L. L\'opez-Ib\'a\~nez, Aurora Melis, Davide Meloni, \'Oscar Vives | Lepton Flavor Violation and Neutrino Masses from $A_5$ and CP in the
Non-Universal MSSM | v2:version published in JHEP. Section 2 added. 34 pages, 10 figures,
5 tables | JHEP06(2019)047 | 10.1007/JHEP06(2019)047 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the phenomenological consequences of embedding a flavor symmetry
based on the groups $A_5$ and CP in a supersymmetric framework. We concentrate
on the leptonic sector, where two different residual symmetries are assumed to
be conserved at LO for charged and neutral leptons. All possible realizations
to generate neutrino masses at tree level are investigated. Sizable flavor
violating effects in the charged lepton sector are unavoidable due to the
non-universality of soft-breaking terms determined by the symmetry. We derive
testable predictions for the neutrino spectrum, lepton mixing and flavor
changing processes with non-trivial relations among observables.
| [
{
"created": "Mon, 14 Jan 2019 19:22:31 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Sep 2019 01:23:10 GMT",
"version": "v2"
}
] | 2019-09-10 | [
[
"López-Ibáñez",
"M. L.",
""
],
[
"Melis",
"Aurora",
""
],
[
"Meloni",
"Davide",
""
],
[
"Vives",
"Óscar",
""
]
] | We analyze the phenomenological consequences of embedding a flavor symmetry based on the groups $A_5$ and CP in a supersymmetric framework. We concentrate on the leptonic sector, where two different residual symmetries are assumed to be conserved at LO for charged and neutral leptons. All possible realizations to generate neutrino masses at tree level are investigated. Sizable flavor violating effects in the charged lepton sector are unavoidable due to the non-universality of soft-breaking terms determined by the symmetry. We derive testable predictions for the neutrino spectrum, lepton mixing and flavor changing processes with non-trivial relations among observables. |
0707.3826 | Chia-Min Lin | Kazunori Kohri, Chia-Min Lin, David H. Lyth | More hilltop inflation models | 12 pages, 25 figures, to appear in JCAP | JCAP0712:004,2007 | 10.1088/1475-7516/2007/12/004 | null | hep-ph astro-ph hep-th | null | Using analytic expressions, we explore the parameter space for hilltop
inflation models with a potential of the form $V_0\pm m^2\phi^2 -a\phi^p$. With
the positive sign and p>2 this converts the original hybrid inflation model
into a hilltop model, allowing the spectral index to agree with the observed
value n=0.95. In some cases the observed value is theoretically favored, while
in others there is only the generic prediction $|n-1|\lsim 1$.
| [
{
"created": "Wed, 25 Jul 2007 20:55:02 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Nov 2007 16:56:04 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Kohri",
"Kazunori",
""
],
[
"Lin",
"Chia-Min",
""
],
[
"Lyth",
"David H.",
""
]
] | Using analytic expressions, we explore the parameter space for hilltop inflation models with a potential of the form $V_0\pm m^2\phi^2 -a\phi^p$. With the positive sign and p>2 this converts the original hybrid inflation model into a hilltop model, allowing the spectral index to agree with the observed value n=0.95. In some cases the observed value is theoretically favored, while in others there is only the generic prediction $|n-1|\lsim 1$. |
2406.14895 | Jing Song | Jing Song, Man-Yu Duan, Luis Roca, Eulogio Oset | Pentaquark molecular states with hidden bottom and double strangeness | 8 pages, 1 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the meson-baryon interaction in coupled channels with the
quantum numbers of the pentaquarks $P_{bss}$ and $P_{bsss}$. The interaction is
derived from an extension of the local hidden gauge approach to the heavy quark
sector, which has demonstrated accurate results compared to experiments
involving $\Omega_{b}$, $\Xi_{b}$ states, and pentaquarks $P_{c}$ and $P_{cs}$.
In our study, we identify several molecular states with small decay widths
within the chosen set of coupled channels. The spin-parity ($J^P$) of these
states is as follows: $J^P={\frac{1}{2}}^-$ for pseudoscalar-baryon
(${\frac{1}{2}}^+$) coupled channels, $J^P={\frac{3}{2}}^-$ for
pseudoscalar-baryon (${\frac{3}{2}}^+$) coupled channels, $J^P={\frac{1}{2}}^-$
and ${\frac{3}{2}}^-$ for vector-baryon (${\frac{1}{2}}^+$) coupled channels,
and $J^P={\frac{1}{2}}^-$, ${\frac{3}{2}}^-$, ${\frac{5}{2}}^-$ for
vector-baryon (${\frac{3}{2}}^+$) coupled channels. We search for the poles of
these states and evaluate their couplings to the different channels.
| [
{
"created": "Fri, 21 Jun 2024 06:31:42 GMT",
"version": "v1"
}
] | 2024-06-24 | [
[
"Song",
"Jing",
""
],
[
"Duan",
"Man-Yu",
""
],
[
"Roca",
"Luis",
""
],
[
"Oset",
"Eulogio",
""
]
] | We investigate the meson-baryon interaction in coupled channels with the quantum numbers of the pentaquarks $P_{bss}$ and $P_{bsss}$. The interaction is derived from an extension of the local hidden gauge approach to the heavy quark sector, which has demonstrated accurate results compared to experiments involving $\Omega_{b}$, $\Xi_{b}$ states, and pentaquarks $P_{c}$ and $P_{cs}$. In our study, we identify several molecular states with small decay widths within the chosen set of coupled channels. The spin-parity ($J^P$) of these states is as follows: $J^P={\frac{1}{2}}^-$ for pseudoscalar-baryon (${\frac{1}{2}}^+$) coupled channels, $J^P={\frac{3}{2}}^-$ for pseudoscalar-baryon (${\frac{3}{2}}^+$) coupled channels, $J^P={\frac{1}{2}}^-$ and ${\frac{3}{2}}^-$ for vector-baryon (${\frac{1}{2}}^+$) coupled channels, and $J^P={\frac{1}{2}}^-$, ${\frac{3}{2}}^-$, ${\frac{5}{2}}^-$ for vector-baryon (${\frac{3}{2}}^+$) coupled channels. We search for the poles of these states and evaluate their couplings to the different channels. |
hep-ph/9305277 | Kingman Cheung | V. Barger, Kingman Cheung, T. Han and D. Zeppenfeld | Finding the Leptonic $WW$ Decay Mode of a Heavy Higgs Boson | LaTex(Revtex), 9 pages, 6 figures (available upon request),
MAD/PH/757 | Phys.Rev.D48:5433-5436,1993 | 10.1103/PhysRevD.48.5433 | null | hep-ph | null | We reanalyze the extraction of the heavy Higgs boson signal $H\rightarrow
W^+W^-\rightarrow \bar\ell\nu,\ell\bar\nu$ $(\ell=e\hbox{ or }\mu)$ from the
Standard Model background at hadron supercolliders, taking into account revised
estimates of the top quark background. With new acceptance criteria the
detection of the signal remains viable. Requiring a forward jet-tag, a central
jet-veto, and a large relative transverse momentum of the two charged leptons
yields $S/\sqrt B>6$ for one year of running at the SSC or LHC.
| [
{
"created": "Mon, 17 May 1993 18:10:16 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Barger",
"V.",
""
],
[
"Cheung",
"Kingman",
""
],
[
"Han",
"T.",
""
],
[
"Zeppenfeld",
"D.",
""
]
] | We reanalyze the extraction of the heavy Higgs boson signal $H\rightarrow W^+W^-\rightarrow \bar\ell\nu,\ell\bar\nu$ $(\ell=e\hbox{ or }\mu)$ from the Standard Model background at hadron supercolliders, taking into account revised estimates of the top quark background. With new acceptance criteria the detection of the signal remains viable. Requiring a forward jet-tag, a central jet-veto, and a large relative transverse momentum of the two charged leptons yields $S/\sqrt B>6$ for one year of running at the SSC or LHC. |
1307.6480 | Laura Lopez Honorez | Federica Giacchino, Laura Lopez-Honorez and Michel H.G. Tytgat | Scalar Dark Matter Models with Significant Internal Bremsstrahlung | 25 pages, 10 figures, typos corrected, added references, matching
version accepted by JCAP | null | 10.1088/1475-7516/2013/10/025 | ULB-TH/13-09 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There has been interest recently on particle physics models that may give
rise to sharp gamma ray spectral features from dark matter annihilation.
Because dark matter is supposed to be electrically neutral, it is challenging
to build weakly interacting massive particle models that may accommodate both a
large cross section into gamma rays at, say, the Galactic center, and the right
dark matter abundance. In this work, we consider the gamma ray signatures of a
class of scalar dark matter models that interact with Standard Model dominantly
through heavy vector-like fermions (the vector-like portal). We focus on a real
scalar singlet S annihilating into lepton-antilepton pairs. Because this
two-body final-state annihilation channel is d-wave suppressed in the chiral
limit, we show that virtual internal bremsstrahlung emission of a gamma ray
gives a large correction, both today and at the time of freeze-out. For the
sake of comparison, we confront this scenario to the familiar case of a
Majorana singlet annihilating into light lepton-antilepton pairs, and show that
the virtual internal bremsstrahlung signal may be enhanced by a factor of (up
to) two orders of magnitude. We discuss the scope and possible generalizations
of the model.
| [
{
"created": "Wed, 24 Jul 2013 16:21:09 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Oct 2013 15:11:58 GMT",
"version": "v2"
}
] | 2015-06-16 | [
[
"Giacchino",
"Federica",
""
],
[
"Lopez-Honorez",
"Laura",
""
],
[
"Tytgat",
"Michel H. G.",
""
]
] | There has been interest recently on particle physics models that may give rise to sharp gamma ray spectral features from dark matter annihilation. Because dark matter is supposed to be electrically neutral, it is challenging to build weakly interacting massive particle models that may accommodate both a large cross section into gamma rays at, say, the Galactic center, and the right dark matter abundance. In this work, we consider the gamma ray signatures of a class of scalar dark matter models that interact with Standard Model dominantly through heavy vector-like fermions (the vector-like portal). We focus on a real scalar singlet S annihilating into lepton-antilepton pairs. Because this two-body final-state annihilation channel is d-wave suppressed in the chiral limit, we show that virtual internal bremsstrahlung emission of a gamma ray gives a large correction, both today and at the time of freeze-out. For the sake of comparison, we confront this scenario to the familiar case of a Majorana singlet annihilating into light lepton-antilepton pairs, and show that the virtual internal bremsstrahlung signal may be enhanced by a factor of (up to) two orders of magnitude. We discuss the scope and possible generalizations of the model. |
hep-ph/0501284 | Defu Hou | Hou Defu | Shear viscosity of hot QCD from transport theory and thermal field
theory in real time formalism | 15 pages with 3 figures | null | null | null | hep-ph | null | We study shear viscosity in weakly coupled hot pure gauge field QCD theory
basing on transport theory and the Kubo formula using the closed time path
formalism (CTP) of real time finite temperature field theory. We show that the
viscosity can be obtained as the integral of a retarded three-point function.
Non-perturbative corrections to the bare one loop result can be obtained by
solving a Schwinger-Dyson type integral equation for this vertex. This integral
equation represents the resummation of an infinite series of ladder diagrams
which all contribute to the leading-log order result. We show that this
integral equation has exactly the same form as the linearized Boltzmann
equation and explain the reason behind this formal equality.
| [
{
"created": "Mon, 31 Jan 2005 09:54:42 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Defu",
"Hou",
""
]
] | We study shear viscosity in weakly coupled hot pure gauge field QCD theory basing on transport theory and the Kubo formula using the closed time path formalism (CTP) of real time finite temperature field theory. We show that the viscosity can be obtained as the integral of a retarded three-point function. Non-perturbative corrections to the bare one loop result can be obtained by solving a Schwinger-Dyson type integral equation for this vertex. This integral equation represents the resummation of an infinite series of ladder diagrams which all contribute to the leading-log order result. We show that this integral equation has exactly the same form as the linearized Boltzmann equation and explain the reason behind this formal equality. |
2012.10633 | Boris Ermolaev | B.I. Ermolaev, S.I. Troyan | Rise of the DIS structure function F_L at small x caused by
double-logarithmic contributions | 19 pp, 2 figs. Comparison with DGLAP and BFKL is presented in more
detail, misprints corrected, some refs added | null | 10.1007/JHEP03(2021)274 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present calculation of F_L in the double-logarithmic approximation and
demonstrate that the synergic effect of the factor 1/x from the
\alpha_s^2-order and the steep x-dependence of the totally resummed double
logarithmic contributions of higher orders ensures the power-like rise of F_L
at small x and arbitrary Q^2.
| [
{
"created": "Sat, 19 Dec 2020 09:10:55 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Jan 2021 10:18:23 GMT",
"version": "v2"
},
{
"created": "Thu, 25 Feb 2021 07:54:48 GMT",
"version": "v3"
}
] | 2021-04-14 | [
[
"Ermolaev",
"B. I.",
""
],
[
"Troyan",
"S. I.",
""
]
] | We present calculation of F_L in the double-logarithmic approximation and demonstrate that the synergic effect of the factor 1/x from the \alpha_s^2-order and the steep x-dependence of the totally resummed double logarithmic contributions of higher orders ensures the power-like rise of F_L at small x and arbitrary Q^2. |
hep-ph/9509382 | Ichio Fukui | I. Fukui and N. Setoh | Scalar-Scalar Ladder Model in the Unequal-Mass Case. II ---Numerical
Studies of the BS Amplitudes --- | 12 pages, Latex, 5 figures appended as an uuencoded Postscript file | Prog.Theor.Phys. 95 (1996) 433-439 | 10.1143/PTP.95.433 | SAGA-HE-93 | hep-ph | null | The Bethe-Salpeter amplitudes of the bound states formed by two scalar
particles with unequal masses are analyzed in the massive scalar particle
exchange ladder model. The norms of the amplitudes are calculated numerically,
and it is confirmed that the norm vanishes for the bound state corresponding to
the complex eigenvalue of the coupling constant. The behaviour of the
Bethe-Salpeter amplitudes in the momentum space is also investigated.
| [
{
"created": "Tue, 26 Sep 1995 03:07:48 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Fukui",
"I.",
""
],
[
"Setoh",
"N.",
""
]
] | The Bethe-Salpeter amplitudes of the bound states formed by two scalar particles with unequal masses are analyzed in the massive scalar particle exchange ladder model. The norms of the amplitudes are calculated numerically, and it is confirmed that the norm vanishes for the bound state corresponding to the complex eigenvalue of the coupling constant. The behaviour of the Bethe-Salpeter amplitudes in the momentum space is also investigated. |
1704.06663 | Ufuk Aydemir | Ufuk Aydemir | A scale at 10 MeV, gravitational topological vacuum, and large extra
dimensions | 8 pages. Minor improvements. Slightly more detailed version of the
published paper | Universe 2018, 4, 80 | 10.3390/universe4070080 | null | hep-ph gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss a possible scale of gravitational origin at around $10$ MeV, or
$10^{-12}$ cm, which arises in the MacDowell-Mansouri formalism of gravity due
to the topological Gauss-Bonnet term in the action, as pointed out by Bjorken
several years ago. A length scale of the same size emerges also in the Kodama
solution in gravity, which is known to be closely related to the
MacDowell-Mansouri formulation. We particularly draw attention to the
intriguing incident that existence of six compact extra dimensions originated
from TeV-scale quantum gravity as well points to a length scale of $10^{-12}$
cm, as the compactification scale. The presence of six such extra dimensions is
also in remarkable consistency with the MacDowell-Mansouri formalism; it
provides a possible explanation for the factor of $\sim10^{120}$ multiplying
the Gauss-Bonnet term in the action. We also comment on the relevant
implications of such a scale regarding the thermal history of the universe
motivated by the fact that it is considerably close to $1-2$ MeV below which
the weak interactions freeze out, leading to Big Bang Nucleosynthesis.
| [
{
"created": "Fri, 21 Apr 2017 18:00:09 GMT",
"version": "v1"
},
{
"created": "Wed, 10 May 2017 07:23:56 GMT",
"version": "v2"
},
{
"created": "Wed, 18 Jul 2018 10:51:50 GMT",
"version": "v3"
}
] | 2018-07-19 | [
[
"Aydemir",
"Ufuk",
""
]
] | We discuss a possible scale of gravitational origin at around $10$ MeV, or $10^{-12}$ cm, which arises in the MacDowell-Mansouri formalism of gravity due to the topological Gauss-Bonnet term in the action, as pointed out by Bjorken several years ago. A length scale of the same size emerges also in the Kodama solution in gravity, which is known to be closely related to the MacDowell-Mansouri formulation. We particularly draw attention to the intriguing incident that existence of six compact extra dimensions originated from TeV-scale quantum gravity as well points to a length scale of $10^{-12}$ cm, as the compactification scale. The presence of six such extra dimensions is also in remarkable consistency with the MacDowell-Mansouri formalism; it provides a possible explanation for the factor of $\sim10^{120}$ multiplying the Gauss-Bonnet term in the action. We also comment on the relevant implications of such a scale regarding the thermal history of the universe motivated by the fact that it is considerably close to $1-2$ MeV below which the weak interactions freeze out, leading to Big Bang Nucleosynthesis. |
1810.10587 | Keith R. Dienes | Keith R. Dienes, Jason Kumar, Patrick Stengel, Brooks Thomas | Cosmological Constraints on Unstable Particles: Numerical Bounds and
Analytic Approximations | 41 pages, LaTeX, 12 figures, 4 tables | Phys. Rev. D 99, 043513 (2019) | 10.1103/PhysRevD.99.043513 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Many extensions of the Standard Model predict large numbers of additional
unstable particles whose decays in the early universe are tightly constrained
by observational data. For example, the decays of such particles can alter the
ratios of light-element abundances, give rise to distortions in the cosmic
microwave background, alter the ionization history of the universe, and
contribute to the diffuse photon flux. Constraints on new physics from such
considerations are typically derived for a single unstable particle species
with a single well-defined mass and characteristic lifetime. In this paper, by
contrast, we investigate the cosmological constraints on theories involving
entire ensembles of decaying particles --- ensembles which span potentially
broad ranges of masses and lifetimes. In addition to providing a detailed
numerical analysis of these constraints, we also formulate a set of simple
analytic approximations for these constraints which may be applied to generic
ensembles of unstable particles which decay into
electromagnetically-interacting final states. We then illustrate how these
analytic approximations can be used to constrain a variety of toy scenarios for
physics beyond the Standard Model. For ease of reference, we also compile our
results in the form of a table which can be consulted independently of the rest
of the paper. It is thus our hope that this work might serve as a useful
reference for future model-builders concerned with cosmological constraints on
decaying particles, regardless of the particular model under study.
| [
{
"created": "Wed, 24 Oct 2018 19:39:16 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Feb 2019 01:58:37 GMT",
"version": "v2"
}
] | 2019-02-20 | [
[
"Dienes",
"Keith R.",
""
],
[
"Kumar",
"Jason",
""
],
[
"Stengel",
"Patrick",
""
],
[
"Thomas",
"Brooks",
""
]
] | Many extensions of the Standard Model predict large numbers of additional unstable particles whose decays in the early universe are tightly constrained by observational data. For example, the decays of such particles can alter the ratios of light-element abundances, give rise to distortions in the cosmic microwave background, alter the ionization history of the universe, and contribute to the diffuse photon flux. Constraints on new physics from such considerations are typically derived for a single unstable particle species with a single well-defined mass and characteristic lifetime. In this paper, by contrast, we investigate the cosmological constraints on theories involving entire ensembles of decaying particles --- ensembles which span potentially broad ranges of masses and lifetimes. In addition to providing a detailed numerical analysis of these constraints, we also formulate a set of simple analytic approximations for these constraints which may be applied to generic ensembles of unstable particles which decay into electromagnetically-interacting final states. We then illustrate how these analytic approximations can be used to constrain a variety of toy scenarios for physics beyond the Standard Model. For ease of reference, we also compile our results in the form of a table which can be consulted independently of the rest of the paper. It is thus our hope that this work might serve as a useful reference for future model-builders concerned with cosmological constraints on decaying particles, regardless of the particular model under study. |
1703.04920 | Nobuhiro Shimizu | N. Shimizu, D. Epifanov, J. Sasaki | The anomalous four-point interaction in the radiative leptonic $\tau$
decay | 4 pages, two figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | As one of the extensions of the Standard Model, we investigate the anomalous
four-point $\tau-W-\nu_\tau-\gamma$ scalar- and tensor-type interactions, which
originate from the gauge invariant dimension-five operators. The coupling
constants are constrained by the measured branching ratio of the $\tau^-
\rightarrow \mu^- \nu_{\tau} \bar{\nu_\mu} \gamma$ decay:
$-4.9<\kappa_\tau^S<9.4$ and $-1.4<\kappa_\tau^T<2.8$ at the 95% confidence
level for the scalar and tensor interactions, respectively.
| [
{
"created": "Wed, 15 Mar 2017 04:29:09 GMT",
"version": "v1"
}
] | 2017-03-16 | [
[
"Shimizu",
"N.",
""
],
[
"Epifanov",
"D.",
""
],
[
"Sasaki",
"J.",
""
]
] | As one of the extensions of the Standard Model, we investigate the anomalous four-point $\tau-W-\nu_\tau-\gamma$ scalar- and tensor-type interactions, which originate from the gauge invariant dimension-five operators. The coupling constants are constrained by the measured branching ratio of the $\tau^- \rightarrow \mu^- \nu_{\tau} \bar{\nu_\mu} \gamma$ decay: $-4.9<\kappa_\tau^S<9.4$ and $-1.4<\kappa_\tau^T<2.8$ at the 95% confidence level for the scalar and tensor interactions, respectively. |
0804.3042 | Felipe J. Llanes-Estrada | Reinhard Alkofer, Christian S. Fischer, Felipe J. Llanes-Estrada and
Kai Schwenzer | The quark-gluon vertex in Landau gauge QCD: Its role in dynamical chiral
symmetry breaking and quark confinement | 64 pages, 31 figures | Annals of Physics 324 (2009) 106 | 10.1016/j.aop.2008.07.001 | null | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The infrared behavior of the quark-gluon vertex of quenched Landau gauge QCD
is studied by analyzing its Dyson-Schwinger equation. Building on previously
obtained results for Green functions in the Yang-Mills sector we analytically
derive the existence of power-law infrared singularities for this vertex. We
establish that dynamical chiral symmetry breaking leads to the self-consistent
generation of components of the quark-gluon vertex forbidden when chiral
symmetry is forced to stay in the Wigner-Weyl mode. In the latter case the
running strong coupling assumes an infrared fixed point. If chiral symmetry is
broken, either dynamically or explicitely, the running coupling is infrared
divergent. Based on a truncation for the quark-gluon vertex Dyson-Schwinger
equation which respects the analytically determined infrared behavior numerical
results for the coupled system of the quark propagator and vertex
Dyson-Schwinger equation are presented. The resulting quark mass function as
well as the vertex function show only a very weak dependence on the current
quark mass in the deep infrared. From this we infer by an analysis of the
quark-quark scattering kernel a linearly rising quark potential with an almost
mass independent string tension in the case of broken chiral symmetry.
Enforcing chiral symmetry does lead to a Coulomb type potential. Therefore we
conclude that chiral symmetry breaking and confinement are closely related.
Furthermore we discuss aspects of confinement as the absence of long-range
van-der-Waals forces and Casimir scaling. An examination of experimental data
for quarkonia provides further evidence for the viability of the presented
mechanism for quark confinement in the Landau gauge.
| [
{
"created": "Fri, 18 Apr 2008 15:43:27 GMT",
"version": "v1"
}
] | 2009-11-13 | [
[
"Alkofer",
"Reinhard",
""
],
[
"Fischer",
"Christian S.",
""
],
[
"Llanes-Estrada",
"Felipe J.",
""
],
[
"Schwenzer",
"Kai",
""
]
] | The infrared behavior of the quark-gluon vertex of quenched Landau gauge QCD is studied by analyzing its Dyson-Schwinger equation. Building on previously obtained results for Green functions in the Yang-Mills sector we analytically derive the existence of power-law infrared singularities for this vertex. We establish that dynamical chiral symmetry breaking leads to the self-consistent generation of components of the quark-gluon vertex forbidden when chiral symmetry is forced to stay in the Wigner-Weyl mode. In the latter case the running strong coupling assumes an infrared fixed point. If chiral symmetry is broken, either dynamically or explicitely, the running coupling is infrared divergent. Based on a truncation for the quark-gluon vertex Dyson-Schwinger equation which respects the analytically determined infrared behavior numerical results for the coupled system of the quark propagator and vertex Dyson-Schwinger equation are presented. The resulting quark mass function as well as the vertex function show only a very weak dependence on the current quark mass in the deep infrared. From this we infer by an analysis of the quark-quark scattering kernel a linearly rising quark potential with an almost mass independent string tension in the case of broken chiral symmetry. Enforcing chiral symmetry does lead to a Coulomb type potential. Therefore we conclude that chiral symmetry breaking and confinement are closely related. Furthermore we discuss aspects of confinement as the absence of long-range van-der-Waals forces and Casimir scaling. An examination of experimental data for quarkonia provides further evidence for the viability of the presented mechanism for quark confinement in the Landau gauge. |
0903.3918 | Piergiulio Lenzi | P. Lenzi and J. M. Butterworth | A study on Matrix Element corrections in inclusive Z/ gamma* production
at LHC as implemented in PYTHIA, HERWIG, ALPGEN and SHERPA | 22 pages, 18 figures | null | null | MCnet/09/06 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study Matrix Element corrections as implemented in four popular event
generators for hadron collisions. We compare PYTHIA, HERWIG, ALPGEN and SHERPA
in the Z/gamma* inclusive production at LHC. PYTHIA and HERWIG are able to
correct the first emission from the shower taking the Matrix Element
calculation for one additional parton into account. SHERPA and ALPGEN are able
to take into account Matrix Element corrections not only for one, but rather
for several hard emissions from the incoming partons. This can be done at the
price of introducing a separation cut to distinguish a Matrix Element and a
Parton Shower populated regions. In this paper we check the effect of Matrix
Element corrections in PYTHIA and HERWIG and we check that results from these
two generators are consistent. Then we turn to SHERPA and ALPGEN, that
implement two different methods to match Matrix Element calculations and Parton
Shower. If we constraint them so that no more than one parton can emerge from
the Matrix Element calculations they should both give results similar to PYTHIA
and HERWIG. In other words PYTHIA and HERWIG provide us with the correct
reference to spot possible issues with the matching prescriptions implemented
in SHERPA and ALPGEN. We also check to what extent the dependency on the Matrix
Element - Parton Shower separation cut is canceled in these two generators.
| [
{
"created": "Mon, 23 Mar 2009 17:59:54 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Mar 2009 08:22:08 GMT",
"version": "v2"
}
] | 2009-03-27 | [
[
"Lenzi",
"P.",
""
],
[
"Butterworth",
"J. M.",
""
]
] | We study Matrix Element corrections as implemented in four popular event generators for hadron collisions. We compare PYTHIA, HERWIG, ALPGEN and SHERPA in the Z/gamma* inclusive production at LHC. PYTHIA and HERWIG are able to correct the first emission from the shower taking the Matrix Element calculation for one additional parton into account. SHERPA and ALPGEN are able to take into account Matrix Element corrections not only for one, but rather for several hard emissions from the incoming partons. This can be done at the price of introducing a separation cut to distinguish a Matrix Element and a Parton Shower populated regions. In this paper we check the effect of Matrix Element corrections in PYTHIA and HERWIG and we check that results from these two generators are consistent. Then we turn to SHERPA and ALPGEN, that implement two different methods to match Matrix Element calculations and Parton Shower. If we constraint them so that no more than one parton can emerge from the Matrix Element calculations they should both give results similar to PYTHIA and HERWIG. In other words PYTHIA and HERWIG provide us with the correct reference to spot possible issues with the matching prescriptions implemented in SHERPA and ALPGEN. We also check to what extent the dependency on the Matrix Element - Parton Shower separation cut is canceled in these two generators. |
hep-ph/9709423 | Joel S. Rozowsky | J.S. Rozowsky | Feynman Diagrams and Cutting Rules | Latex, 22 pages, 6 figures | null | null | UCLA/97/TEP/23 | hep-ph hep-th | null | We show how Feynman diagrams may be evaluated to take advantage of recent
developments in the application of Cutkosky rules to the calculation of
one-loop amplitudes. A sample calculation of gg->gH, previously calculated by
Ellis et al., is presented illustrating this equivalence. This example
demonstrates the use of cutting rules for massive amplitudes.
| [
{
"created": "Tue, 23 Sep 1997 00:44:01 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Rozowsky",
"J. S.",
""
]
] | We show how Feynman diagrams may be evaluated to take advantage of recent developments in the application of Cutkosky rules to the calculation of one-loop amplitudes. A sample calculation of gg->gH, previously calculated by Ellis et al., is presented illustrating this equivalence. This example demonstrates the use of cutting rules for massive amplitudes. |
1802.05508 | S.S. Pozdnyakov | S. Bondarenko, S.S. Pozdnyakov | NNLO classical solution for Lipatov's effective action for reggeized
gluons | 12 pages; submitted to Eur.Phys.Jour. C | null | 10.1142/S0217751X19501112 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the formalism of small-x effective action for reggeized gluons,
Gribov (Sov Phys JETP 26:414, 1968), Lipatov (Nucl Phys B 452:369, 1995; Phys
Rep 286:131, 1997; Subnucl Ser 49:131, 2013, Int J Mod Phys Conf Ser
39:1560082, 2015; Int J Mod Phys A 31(28/29):1645011, 2016; EPJ Web Conf
125:01010, 2016) and Lipatov et al. (Sov J Nucl Phys 23:338, 1976; Sov Phys
JETP 45:199, 1977; Sov J Nucl Phys 28:822, 1978), and, following to the
approach developed in Bondarenko et al. (Eur Phys J C 77(8):527, 2017, Eur Phys
J C 77(9):630, 2017), calculate the classical gluon field to NNLO precision
with fermion loops included. It is demonstrated, that the the self-consistency
of the equations of motion in each perturbatie order in the approach is
equivalent to the transversality conditions applied to the solutions of the
equations in the lower orders, that allows to construct the solutions with the
help of some recursive scheme. Applications of the obtained results are also
discussed.
| [
{
"created": "Thu, 15 Feb 2018 12:41:17 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Mar 2018 16:37:05 GMT",
"version": "v2"
}
] | 2019-09-04 | [
[
"Bondarenko",
"S.",
""
],
[
"Pozdnyakov",
"S. S.",
""
]
] | We consider the formalism of small-x effective action for reggeized gluons, Gribov (Sov Phys JETP 26:414, 1968), Lipatov (Nucl Phys B 452:369, 1995; Phys Rep 286:131, 1997; Subnucl Ser 49:131, 2013, Int J Mod Phys Conf Ser 39:1560082, 2015; Int J Mod Phys A 31(28/29):1645011, 2016; EPJ Web Conf 125:01010, 2016) and Lipatov et al. (Sov J Nucl Phys 23:338, 1976; Sov Phys JETP 45:199, 1977; Sov J Nucl Phys 28:822, 1978), and, following to the approach developed in Bondarenko et al. (Eur Phys J C 77(8):527, 2017, Eur Phys J C 77(9):630, 2017), calculate the classical gluon field to NNLO precision with fermion loops included. It is demonstrated, that the the self-consistency of the equations of motion in each perturbatie order in the approach is equivalent to the transversality conditions applied to the solutions of the equations in the lower orders, that allows to construct the solutions with the help of some recursive scheme. Applications of the obtained results are also discussed. |
2311.04993 | Jose Vieyra | J. Vieyra, A. Mart\'inez, M. Neri and A. Hern\'andez-Galeana | Radiative Corrections to the Muon Polarization in the Semileptonic Decay
of a Neutral Kaon | arXiv admin note: substantial text overlap with arXiv:2004.05402 | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | A model-independent expression for the Dalitz plot of the semileptonic decays
of a neutral kaon $K_{\mu 3}^0$, including radiative corrections to order
$\mathcal{O}[(\alpha / \pi )(q/M_1)]$, where $q$ is the four-momentum transfer
and $M_1$ is the mass of the decaying kaon, is presented. In this paper the
emitted muon is considered to be polarized so the analysis is centered on
numerically evaluating the radiative corrections to the longitudinal,
transverse, and normal polarization muon components. The model dependence of
radiative corrections is kept in general form within this approximation, which
is useful for model-independent experimental analyses. The final expressions,
with the triple integration of the bremsstrahlung photon variables are ready to
be performed numerically. The radiative corrections to the components of the
muon polarization are found to be very small compared to their respective
uncorrected values.
| [
{
"created": "Wed, 8 Nov 2023 19:49:39 GMT",
"version": "v1"
}
] | 2023-11-10 | [
[
"Vieyra",
"J.",
""
],
[
"Martínez",
"A.",
""
],
[
"Neri",
"M.",
""
],
[
"Hernández-Galeana",
"A.",
""
]
] | A model-independent expression for the Dalitz plot of the semileptonic decays of a neutral kaon $K_{\mu 3}^0$, including radiative corrections to order $\mathcal{O}[(\alpha / \pi )(q/M_1)]$, where $q$ is the four-momentum transfer and $M_1$ is the mass of the decaying kaon, is presented. In this paper the emitted muon is considered to be polarized so the analysis is centered on numerically evaluating the radiative corrections to the longitudinal, transverse, and normal polarization muon components. The model dependence of radiative corrections is kept in general form within this approximation, which is useful for model-independent experimental analyses. The final expressions, with the triple integration of the bremsstrahlung photon variables are ready to be performed numerically. The radiative corrections to the components of the muon polarization are found to be very small compared to their respective uncorrected values. |
0905.4462 | Claudio Coriano | Claudio Coriano, Marco Guzzi | Axions from Intersecting Branes and Decoupled Chiral Fermions at the
Large Hadron Collider | 64 pages, 15 Figs | Nucl.Phys.B826:87-147,2010 | 10.1016/j.nuclphysb.2009.09.031 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a study of a class of effective actions which show typical
axion-like interactions, and of their possible effects at the Large Hadron
Collider. One important feature of these models is the presence of one
pseudoscalar which is a generalization of the Peccei-Quinn axion. This can be
very light and very weakly coupled, with a mass which is unrelated to its
couplings to the gauge fields, described by Wess Zumino interactions.
We discuss two independent realizations of these models, one derived from the
theory of intersecting branes and the second one obtained by decoupling one
chiral fermion per generation (one right-handed neutrino) from an anomaly-free
mother theory. The key features of this second realization are illustrated
using a simple example.
Charge assignments of intersecting branes can be easily reproduced by the
chiral decoupling approach, which remains more general at the level of the
solution of its anomaly equations. Using considerations based on its lifetime,
we show that in brane models the axion can be dark matter only if its mass is
ultralight ($\sim 10^{-4}$ eV), while in the case of fermion decoupling it can
reach the GeV region, due to the absence of fermion couplings between the heavy
Higgs and the light fermion spectrum. For a GeV axion derived from brane models
we present a detailed discussion of its production rates at the LHC.
| [
{
"created": "Wed, 27 May 2009 16:03:01 GMT",
"version": "v1"
}
] | 2009-11-18 | [
[
"Coriano",
"Claudio",
""
],
[
"Guzzi",
"Marco",
""
]
] | We present a study of a class of effective actions which show typical axion-like interactions, and of their possible effects at the Large Hadron Collider. One important feature of these models is the presence of one pseudoscalar which is a generalization of the Peccei-Quinn axion. This can be very light and very weakly coupled, with a mass which is unrelated to its couplings to the gauge fields, described by Wess Zumino interactions. We discuss two independent realizations of these models, one derived from the theory of intersecting branes and the second one obtained by decoupling one chiral fermion per generation (one right-handed neutrino) from an anomaly-free mother theory. The key features of this second realization are illustrated using a simple example. Charge assignments of intersecting branes can be easily reproduced by the chiral decoupling approach, which remains more general at the level of the solution of its anomaly equations. Using considerations based on its lifetime, we show that in brane models the axion can be dark matter only if its mass is ultralight ($\sim 10^{-4}$ eV), while in the case of fermion decoupling it can reach the GeV region, due to the absence of fermion couplings between the heavy Higgs and the light fermion spectrum. For a GeV axion derived from brane models we present a detailed discussion of its production rates at the LHC. |
2305.05681 | Tanner Trickle | Asher Berlin, Tanner Trickle | Absorption of Axion Dark Matter in a Magnetized Medium | 10 pages, 2 figures | null | null | FERMILAB-PUB-23-168-SQMS-T | hep-ph astro-ph.CO cond-mat.mtrl-sci hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Detection of axion dark matter heavier than a meV is hindered by its small
wavelength, which limits the useful volume of traditional experiments. This
problem can be avoided by directly detecting in-medium excitations, whose $\sim
\text{meV} - \text{eV}$ energies are decoupled from the detector size. We show
that for any target inside a magnetic field, the absorption rate of
electromagnetically-coupled axions into in-medium excitations is determined by
the dielectric function. As a result, the plethora of candidate targets
previously identified for sub-GeV dark matter searches can be repurposed as
broadband axion detectors. We find that a $\text{kg} \cdot \text{yr}$ exposure
with noise levels comparable to recent measurements is sufficient to probe
parameter space currently unexplored by laboratory tests. Noise reduction by
only a few orders of magnitude can enable sensitivity to the QCD axion in the
$\sim 10 \ \text{meV} - 10 \ \text{eV}$ mass range.
| [
{
"created": "Tue, 9 May 2023 18:00:00 GMT",
"version": "v1"
}
] | 2023-05-11 | [
[
"Berlin",
"Asher",
""
],
[
"Trickle",
"Tanner",
""
]
] | Detection of axion dark matter heavier than a meV is hindered by its small wavelength, which limits the useful volume of traditional experiments. This problem can be avoided by directly detecting in-medium excitations, whose $\sim \text{meV} - \text{eV}$ energies are decoupled from the detector size. We show that for any target inside a magnetic field, the absorption rate of electromagnetically-coupled axions into in-medium excitations is determined by the dielectric function. As a result, the plethora of candidate targets previously identified for sub-GeV dark matter searches can be repurposed as broadband axion detectors. We find that a $\text{kg} \cdot \text{yr}$ exposure with noise levels comparable to recent measurements is sufficient to probe parameter space currently unexplored by laboratory tests. Noise reduction by only a few orders of magnitude can enable sensitivity to the QCD axion in the $\sim 10 \ \text{meV} - 10 \ \text{eV}$ mass range. |
1204.1061 | David McKeen | Patrick Draper and David McKeen | Diphotons from Tetraphotons in the Decay of a 125 GeV Higgs at the LHC | 14 pages, 7 figures, revtex4-1; v2: references added and rearranged,
g-2 limit improved, published version; v3: typos corrected | Phys.Rev.D85:115023,2012 | 10.1103/PhysRevD.85.115023 | SCIPP-12/04 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently the ATLAS and CMS experiments have presented data hinting at the
presence of a Higgs boson at $m_h\simeq125$ GeV. The best-fit
$h\rightarrow\gamma\gamma$ rate averaged over the two experiments is
approximately $2.1\pm0.5$ times the Standard Model prediction. We study the
possibility that the excess relative to the Standard Model is due to
$h\rightarrow aa$ decays, where $a$ is a light pseudoscalar that decays
predominantly into $\gamma\gamma$. Although this process yields $4\gamma$ final
states, if the pseudoscalar has a mass of the order tens of MeV, the two
photons from each $a$ decay can be so highly collimated that they may be
identified as a single photon. Some fraction of the events then contribute to
an effective $h\rightarrow\gamma\gamma$ signal. We study the constraints on the
parameter space where the net $h\rightarrow\gamma\gamma$ rate is enhanced over
the Standard Model by this mechanism and describe some simple models that give
rise to the pseudoscalar-photon interaction. Further tests and prospects for
searches in the near future are discussed.
| [
{
"created": "Wed, 4 Apr 2012 20:00:48 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Jun 2012 05:58:34 GMT",
"version": "v2"
},
{
"created": "Fri, 29 Jun 2012 22:01:04 GMT",
"version": "v3"
}
] | 2012-07-03 | [
[
"Draper",
"Patrick",
""
],
[
"McKeen",
"David",
""
]
] | Recently the ATLAS and CMS experiments have presented data hinting at the presence of a Higgs boson at $m_h\simeq125$ GeV. The best-fit $h\rightarrow\gamma\gamma$ rate averaged over the two experiments is approximately $2.1\pm0.5$ times the Standard Model prediction. We study the possibility that the excess relative to the Standard Model is due to $h\rightarrow aa$ decays, where $a$ is a light pseudoscalar that decays predominantly into $\gamma\gamma$. Although this process yields $4\gamma$ final states, if the pseudoscalar has a mass of the order tens of MeV, the two photons from each $a$ decay can be so highly collimated that they may be identified as a single photon. Some fraction of the events then contribute to an effective $h\rightarrow\gamma\gamma$ signal. We study the constraints on the parameter space where the net $h\rightarrow\gamma\gamma$ rate is enhanced over the Standard Model by this mechanism and describe some simple models that give rise to the pseudoscalar-photon interaction. Further tests and prospects for searches in the near future are discussed. |
1408.3563 | Poulose Poulose Dr. | Satendra Kumar and P. Poulose | Influence of anomalous VVH and VVHH on determination of Higgs self
couplings at ILC | 17 pages, 11 figures, references added | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recent discovery of a Higgs boson at LHC, while establishing the Higgs
mechanism as the way of electroweak symmetry breaking, started an era of
precision measurements involving the Higgs boson. In an effective Lagrangian
framework, we consider the e+e- --> ZHH process, at an ILC running at a centre
of mass energy of 800 GeV to investigate the effect of the ZZH and ZZHH
couplings on the sensitivity of HHH coupling on this process. Our results show
that the sensitivity of the trilinear Higgs self couplings on this process has
somewhat strong dependence on the Higgs-gauge boson couplings. Single and two
parameter reach of ILC with integrated luminosity of 1000 /fb are obtained on
the effective couplings, c6 and cH, which are related to the HHH couplings,
indicating how these limits are affected by the presence of anomalous ZZH and
ZZHH couplings. The kinematic distributions studied to understand the effect of
the anomalous couplings, again, show strong influence of Z-H couplings on the
dependence of these distributions on HHH coupling. Similar results are
indicated in the case of the process, e+e- --> nu nu HH, considered at a centre
of mass energy of 2 TeV, where the cross section is large enough. The effect of
WWH and WWHH couplings on the sensitivity of HHH coupling is clearely
established through our analyses of this process.
| [
{
"created": "Fri, 15 Aug 2014 15:30:05 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Aug 2014 04:21:38 GMT",
"version": "v2"
}
] | 2014-08-26 | [
[
"Kumar",
"Satendra",
""
],
[
"Poulose",
"P.",
""
]
] | The recent discovery of a Higgs boson at LHC, while establishing the Higgs mechanism as the way of electroweak symmetry breaking, started an era of precision measurements involving the Higgs boson. In an effective Lagrangian framework, we consider the e+e- --> ZHH process, at an ILC running at a centre of mass energy of 800 GeV to investigate the effect of the ZZH and ZZHH couplings on the sensitivity of HHH coupling on this process. Our results show that the sensitivity of the trilinear Higgs self couplings on this process has somewhat strong dependence on the Higgs-gauge boson couplings. Single and two parameter reach of ILC with integrated luminosity of 1000 /fb are obtained on the effective couplings, c6 and cH, which are related to the HHH couplings, indicating how these limits are affected by the presence of anomalous ZZH and ZZHH couplings. The kinematic distributions studied to understand the effect of the anomalous couplings, again, show strong influence of Z-H couplings on the dependence of these distributions on HHH coupling. Similar results are indicated in the case of the process, e+e- --> nu nu HH, considered at a centre of mass energy of 2 TeV, where the cross section is large enough. The effect of WWH and WWHH couplings on the sensitivity of HHH coupling is clearely established through our analyses of this process. |
1403.2099 | Stephen Adler | Stephen L. Adler | SU(8) family unification with boson-fermion balance | Latex, 20 pages. To appear in a World Scientific volume celebrating
the 50th anniversary of the quark model, H. Fritzsch and M. Gell-Mann, eds.,
and also in International Journal of Modern Physics A, Vol. 29 (2014) 1450130
(18 pages) | International Journal of Modern Physics A Vol. 29 (2014) 1450130 | 10.1142/S0217751X14501309 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We formulate an $SU(8)$ family unification model motivated by requiring that
the theory should incorporate the graviton, gravitinos, and the fermions and
gauge fields of the standard model, with boson--fermion balance. Gauge field
$SU(8)$ anomalies cancel between the gravitinos and spin $\frac {1}{2}$
fermions. The 56 of scalars breaks $SU(8)$ to $SU(3)_{family} \times
SU(5)\times U(1)/Z_5$, with the fermion representation content needed for
"flipped" $SU(5)$ with three families, and with residual scalars in the $10$
and $\overline{10}$ representations that break flipped $SU(5)$ to the standard
model. Dynamical symmetry breaking can account for the generation of $5$
representation scalars needed to break the electroweak group. Yukawa couplings
of the 56 scalars to the fermions are forbidden by chiral and gauge symmetries,
so in the first stage of $SU(8)$ breaking fermions remain massless. In the
limit of vanishing gauge coupling, there are $N=1$ and $N=8$ supersymmetries
relating the scalars to the fermions, which restrict the form of scalar
self-couplings and should improve the convergence of perturbation theory, if
not making the theory finite and "calculable". In an Appendix we give an
analysis of symmetry breaking by a Higgs component, such as the $(1,1)(-15)$ of
the $SU(8)$ 56 under $SU(8) \supset SU(3) \times SU(5) \times U(1)$, which has
nonzero $U(1)$ generator.
| [
{
"created": "Sun, 9 Mar 2014 20:22:17 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Mar 2014 19:48:48 GMT",
"version": "v2"
},
{
"created": "Mon, 24 Mar 2014 15:06:47 GMT",
"version": "v3"
},
{
"created": "Tue, 3 Jun 2014 20:12:06 GMT",
"version": "v4"
},
{
"cre... | 2015-02-11 | [
[
"Adler",
"Stephen L.",
""
]
] | We formulate an $SU(8)$ family unification model motivated by requiring that the theory should incorporate the graviton, gravitinos, and the fermions and gauge fields of the standard model, with boson--fermion balance. Gauge field $SU(8)$ anomalies cancel between the gravitinos and spin $\frac {1}{2}$ fermions. The 56 of scalars breaks $SU(8)$ to $SU(3)_{family} \times SU(5)\times U(1)/Z_5$, with the fermion representation content needed for "flipped" $SU(5)$ with three families, and with residual scalars in the $10$ and $\overline{10}$ representations that break flipped $SU(5)$ to the standard model. Dynamical symmetry breaking can account for the generation of $5$ representation scalars needed to break the electroweak group. Yukawa couplings of the 56 scalars to the fermions are forbidden by chiral and gauge symmetries, so in the first stage of $SU(8)$ breaking fermions remain massless. In the limit of vanishing gauge coupling, there are $N=1$ and $N=8$ supersymmetries relating the scalars to the fermions, which restrict the form of scalar self-couplings and should improve the convergence of perturbation theory, if not making the theory finite and "calculable". In an Appendix we give an analysis of symmetry breaking by a Higgs component, such as the $(1,1)(-15)$ of the $SU(8)$ 56 under $SU(8) \supset SU(3) \times SU(5) \times U(1)$, which has nonzero $U(1)$ generator. |
hep-ph/9608427 | Vittorio Del Duca | Vittorio Del Duca | Large Rapidity Gaps between Jets at HERA and at the Tevatron | LaTeX, 5 pages. To appear in the Proceedings of the International
Workshop on Deep Inelastic Scattering and Related Phenomena, Roma, Italy,
April 1996 | null | null | EDINBURGH 96/6 | hep-ph | null | In this talk I consider the formation of a rapidity gap in hadron production
between two jets.
| [
{
"created": "Fri, 23 Aug 1996 16:44:22 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Del Duca",
"Vittorio",
""
]
] | In this talk I consider the formation of a rapidity gap in hadron production between two jets. |
hep-ph/0205147 | Sanghyeon Chang | Sanghyeon Chang and T. K. Kuo | Renormalization Invariants of the Neutrino Mass Matrix | 11 pages, no figure | Phys.Rev. D66 (2002) 111302 | 10.1103/PhysRevD.66.111302 | null | hep-ph | null | The renormalization evolution of all parameters in the neutrino mass matrix
depends only on one variable, the energy scale. This fact, coupled with
rephasing considerations, leads to a set of renormalization invariants,
correlating the evolution of physical parameters. For the general three flavor
case, we obtain these invariants explicitly and discuss their implications.
| [
{
"created": "Tue, 14 May 2002 20:06:18 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Chang",
"Sanghyeon",
""
],
[
"Kuo",
"T. K.",
""
]
] | The renormalization evolution of all parameters in the neutrino mass matrix depends only on one variable, the energy scale. This fact, coupled with rephasing considerations, leads to a set of renormalization invariants, correlating the evolution of physical parameters. For the general three flavor case, we obtain these invariants explicitly and discuss their implications. |
1309.5825 | Asmaa Shalaby Mrs. | N.M. El Naggar, L.I. Abou Salem, A.G. Shalaby, and M. A. Bourham | The equation of state for non-ideal quark gluon plasma | 19 pages, 9 figures | Physical Science International Journal 4(7): 2014 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The mass spectra of quarkonium systems at temperature equal zero are analyzed
by solving the non-relativistic radial wave equation using the internal energy
potential. The QGP matter is studied through the dissociations of quarkonium
systems. A modified form of the internal energy potential function is used to
determine the EoS at different number of quark flavors by using Mayer s cluster
expansion theory and phenomenological thermodynamic model. The thermodynamic
model gives a good agreement with the lattice results rather than Mayer s
cluster expansion theory. One can conclude that, the Mayer s cluster expansion
theory may be more suitable to study a weakly coupled plasma while, the QGP may
be considered as a strongly interacting plasma.
| [
{
"created": "Mon, 2 Sep 2013 04:38:56 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Oct 2013 21:55:42 GMT",
"version": "v2"
}
] | 2014-08-26 | [
[
"Naggar",
"N. M. El",
""
],
[
"Salem",
"L. I. Abou",
""
],
[
"Shalaby",
"A. G.",
""
],
[
"Bourham",
"M. A.",
""
]
] | The mass spectra of quarkonium systems at temperature equal zero are analyzed by solving the non-relativistic radial wave equation using the internal energy potential. The QGP matter is studied through the dissociations of quarkonium systems. A modified form of the internal energy potential function is used to determine the EoS at different number of quark flavors by using Mayer s cluster expansion theory and phenomenological thermodynamic model. The thermodynamic model gives a good agreement with the lattice results rather than Mayer s cluster expansion theory. One can conclude that, the Mayer s cluster expansion theory may be more suitable to study a weakly coupled plasma while, the QGP may be considered as a strongly interacting plasma. |
1712.05173 | Roman Nikolaevich Lee | Roman N. Lee and Kirill T. Mingulov | DREAM, a program for arbitrary-precision computation of dimensional
recurrence relations solutions, and its applications | 17 pages, minor changes | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the Mathematica package DREAM for arbitrarily high precision
computation of multiloop integrals within the DRA (Dimensional Recurrence &
Analyticity) method as solutions of dimensional recurrence relations. Starting
from these relations, the package automatically constructs the inhomogeneous
solutions and reduces the manual efforts to setting proper homogeneous
solutions. DREAM also provides means to define the homogeneous solutions of the
higher-order recurrence relations (and can construct those of the first-order
recurrence relations automatically). Therefore, this package can be used to
apply the DRA method to the topologies with sectors having more than one master
integral. Two nontrivial examples are presented: four-loop fully massive
tadpole diagrams of cat-eye topology and three-loop cut diagrams which are
necessary for computation of the width of the para-positronium decay into four
photons. The analytical form of this width is obtained here for the first time
to the best of our knowledge.
| [
{
"created": "Thu, 14 Dec 2017 11:10:22 GMT",
"version": "v1"
},
{
"created": "Tue, 9 Jan 2018 09:00:40 GMT",
"version": "v2"
}
] | 2018-01-10 | [
[
"Lee",
"Roman N.",
""
],
[
"Mingulov",
"Kirill T.",
""
]
] | We present the Mathematica package DREAM for arbitrarily high precision computation of multiloop integrals within the DRA (Dimensional Recurrence & Analyticity) method as solutions of dimensional recurrence relations. Starting from these relations, the package automatically constructs the inhomogeneous solutions and reduces the manual efforts to setting proper homogeneous solutions. DREAM also provides means to define the homogeneous solutions of the higher-order recurrence relations (and can construct those of the first-order recurrence relations automatically). Therefore, this package can be used to apply the DRA method to the topologies with sectors having more than one master integral. Two nontrivial examples are presented: four-loop fully massive tadpole diagrams of cat-eye topology and three-loop cut diagrams which are necessary for computation of the width of the para-positronium decay into four photons. The analytical form of this width is obtained here for the first time to the best of our knowledge. |
hep-ph/0605031 | Takaaki Nomura | Takaaki Nomura, Joe Sato and Takashi Shimomura | Laser Irradiated Enhancement of the Atomic Electron Capture Rate in
search of New Physics | 14 pages, 7 figures, editing and typos corrected, title changed | Prog.Theor.Phys.117:401-414,2007 | 10.1143/PTP.117.401 | STUPP-06-184 | hep-ph | null | Electron capture processes are important in the search for new physics. In
this context, a high capture rate is desired. We investigate the possibility of
enhancing the electron capture rate by irradiating laser beam to ''atom''. The
possibility of such enhancement can be understood as a consequence of an
enhancement of the electron wave function at the origin, $\Psi (0)$, through an
increased effective mass of the electron. We find that an order of magnitude
enhancement can be realized by using a laser with intensity on the order of
$10^{10}$ W/mm$^2$ and a photon energy on the order of $10^{-3}$ eV.
| [
{
"created": "Wed, 3 May 2006 08:51:48 GMT",
"version": "v1"
},
{
"created": "Sat, 16 Jun 2007 11:34:54 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Nomura",
"Takaaki",
""
],
[
"Sato",
"Joe",
""
],
[
"Shimomura",
"Takashi",
""
]
] | Electron capture processes are important in the search for new physics. In this context, a high capture rate is desired. We investigate the possibility of enhancing the electron capture rate by irradiating laser beam to ''atom''. The possibility of such enhancement can be understood as a consequence of an enhancement of the electron wave function at the origin, $\Psi (0)$, through an increased effective mass of the electron. We find that an order of magnitude enhancement can be realized by using a laser with intensity on the order of $10^{10}$ W/mm$^2$ and a photon energy on the order of $10^{-3}$ eV. |
hep-ph/0504001 | Alexander Belyaev | Howard Baer, Azar Mustafayev, Stefano Profumo, Alexander Belyaev,
Xerxes Tata | Direct, Indirect and Collider Detection of Neutralino Dark Matter In
SUSY Models with Non-universal Higgs Masses | LaTeX, 48pages, 26 Figures. The version with high resolution Figures
is available at http://hep.pa.msu.edu/belyaev/public/projects/nuhm/nuhm.ps | JHEP 0507:065,2005 | 10.1088/1126-6708/2005/07/065 | null | hep-ph | null | In supersymmetric models with gravity-mediated SUSY breaking, universality of
soft SUSY breaking sfermion masses m_0 is motivated by the need to suppress
unwanted flavor changing processes. The same motivation, however, does not
apply to soft breaking Higgs masses, which may in general have independent
masses from matter scalars at the GUT scale. We explore phenomenological
implications of both the one-parameter and two-parameter non-universal Higgs
mass models (NUHM1 and NUHM2), and examine the parameter ranges compatible with
Omega_CDM h^2, BF(b --> s,gamma) and (g-2)_mu constraints. In contrast to the
mSUGRA model, in both NUHM1 and NUHM2 models, the dark matter A-annihilation
funnel can be reached at low values of tan(beta), while the higgsino dark
matter annihilation regions can be reached for low values of m_0. We show that
there may be observable rates for indirect and direct detection of neutralino
cold dark matter in phenomenologically aceptable ranges of parameter space. We
also examine implications of the NUHM models for the Fermilab Tevatron, the
CERN LHC and a Sqrt(s)=0.5-1 TeV e+e- linear collider. Novel possibilities
include: very light s-top_R, s-charm_R squark and slepton_L masses as well as
light charginos and neutralinos and H, A and H^+/- Higgs bosons.
| [
{
"created": "Fri, 1 Apr 2005 17:14:37 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Jul 2005 19:17:35 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Baer",
"Howard",
""
],
[
"Mustafayev",
"Azar",
""
],
[
"Profumo",
"Stefano",
""
],
[
"Belyaev",
"Alexander",
""
],
[
"Tata",
"Xerxes",
""
]
] | In supersymmetric models with gravity-mediated SUSY breaking, universality of soft SUSY breaking sfermion masses m_0 is motivated by the need to suppress unwanted flavor changing processes. The same motivation, however, does not apply to soft breaking Higgs masses, which may in general have independent masses from matter scalars at the GUT scale. We explore phenomenological implications of both the one-parameter and two-parameter non-universal Higgs mass models (NUHM1 and NUHM2), and examine the parameter ranges compatible with Omega_CDM h^2, BF(b --> s,gamma) and (g-2)_mu constraints. In contrast to the mSUGRA model, in both NUHM1 and NUHM2 models, the dark matter A-annihilation funnel can be reached at low values of tan(beta), while the higgsino dark matter annihilation regions can be reached for low values of m_0. We show that there may be observable rates for indirect and direct detection of neutralino cold dark matter in phenomenologically aceptable ranges of parameter space. We also examine implications of the NUHM models for the Fermilab Tevatron, the CERN LHC and a Sqrt(s)=0.5-1 TeV e+e- linear collider. Novel possibilities include: very light s-top_R, s-charm_R squark and slepton_L masses as well as light charginos and neutralinos and H, A and H^+/- Higgs bosons. |
hep-ph/0001033 | Werner Porod | W. Porod, D. Restrepo, and J.W.F. Valle | Light Stop: MSSM versus R-parity violation | LaTex, including 3 eps figures, 10 pages, report number added, a few
typographical errors corrected, contribution to "Physics with a
High-Luminosity e+e- Linear Collider", DESY/ECFA LC Workshop, DESY 99-123F | null | null | FTUV/00-7, IFIC/00-07, LC-TH-2000-005 | hep-ph | null | We discuss the phenomenology of the lightest stops in models where R-parity
is broken by bilinear terms. In this class of models we consider scenarios
where the R-parity breaking two-body decay stop_1 -> tau + b competes with the
leading three-body decays stop_1 -> W^+ + b + neutralino_1, H^+ + b +
neutralino_1, b slepton^+_i neutrino_l, b sneutrino_l l^+ (l=e, mu, tau). We
demonstrate that the R-parity violating decay can be the dominant one. In
particular we focus on the implications for a future electron posistion Linear
Collider.
| [
{
"created": "Wed, 5 Jan 2000 11:24:37 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Jan 2000 12:18:17 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Porod",
"W.",
""
],
[
"Restrepo",
"D.",
""
],
[
"Valle",
"J. W. F.",
""
]
] | We discuss the phenomenology of the lightest stops in models where R-parity is broken by bilinear terms. In this class of models we consider scenarios where the R-parity breaking two-body decay stop_1 -> tau + b competes with the leading three-body decays stop_1 -> W^+ + b + neutralino_1, H^+ + b + neutralino_1, b slepton^+_i neutrino_l, b sneutrino_l l^+ (l=e, mu, tau). We demonstrate that the R-parity violating decay can be the dominant one. In particular we focus on the implications for a future electron posistion Linear Collider. |
hep-ph/0508151 | Ulrich Baur | U. Baur (Buffalo) | Probing Electroweak Top Quark Couplings at Hadron and Lepton Colliders | 5 pages, 2 figures, 1 table, talk given at LCWS05, Stanford, CA,
March 2005, to appear in the proceedings | null | null | null | hep-ph | null | The International Linear Collider (ILC) will be able to precisely measure the
electroweak couplings of the top in e+e- -> tt~. We compare the limits which
can be achieved at the ILC with those which can be obtained in tt~gamma$ and
tt~Z production at the Large Hadron Collider (LHC).
| [
{
"created": "Fri, 12 Aug 2005 18:53:50 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Baur",
"U.",
"",
"Buffalo"
]
] | The International Linear Collider (ILC) will be able to precisely measure the electroweak couplings of the top in e+e- -> tt~. We compare the limits which can be achieved at the ILC with those which can be obtained in tt~gamma$ and tt~Z production at the Large Hadron Collider (LHC). |
1608.02101 | Eleazar Cuautle | E. Cuautle and G. Pai\'c | The energy density representation of the strangeness enhancement from
p+p to Pb+Pb | 5 pages, 3 figures | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The energy density is the prime parameter to define the deconfinement of
quarks and gluons occurring in collisions of heavy ions. Recently, there is
mounting evidence that many observables in proton-proton collisions behave in a
manner very similar to the one observed in heavy ions. We present as an
additional piece of evidence, a scaling of the strange particle yields as a
function of the energy density of the three collision systems: p+p p+Pb and
Pb+Pb, using the latest results of the ALICE collaboration.
| [
{
"created": "Sat, 6 Aug 2016 12:34:57 GMT",
"version": "v1"
}
] | 2016-08-09 | [
[
"Cuautle",
"E.",
""
],
[
"Paić",
"G.",
""
]
] | The energy density is the prime parameter to define the deconfinement of quarks and gluons occurring in collisions of heavy ions. Recently, there is mounting evidence that many observables in proton-proton collisions behave in a manner very similar to the one observed in heavy ions. We present as an additional piece of evidence, a scaling of the strange particle yields as a function of the energy density of the three collision systems: p+p p+Pb and Pb+Pb, using the latest results of the ALICE collaboration. |
1109.6027 | Thomas Becher | Thomas Becher, Matthias Neubert and Daniel Wilhelm | Electroweak Gauge-Boson Production at Small q_T: Infrared Safety from
the Collinear Anomaly | 34 pages, 9 figures | null | 10.1007/JHEP02(2012)124 | MZ-TH/11-29 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using methods from effective field theory, we develop a novel, systematic
framework for the calculation of the cross sections for electroweak gauge-boson
production at small and very small transverse momentum q_T, in which large
logarithms of the scale ratio M_V/q_T are resummed to all orders. These cross
sections receive logarithmically enhanced corrections from two sources: the
running of the hard matching coefficient and the collinear factorization
anomaly. The anomaly leads to the dynamical generation of a non-perturbative
scale q_* ~ M_V e^{-const/\alpha_s(M_V)}, which protects the processes from
receiving large long-distance hadronic contributions. Expanding the cross
sections in either \alpha_s or q_T generates strongly divergent series, which
must be resummed. As a by-product, we obtain an explicit non-perturbative
expression for the intercept of the cross sections at q_T=0, including the
normalization and first-order \alpha_s(q_*) correction. We perform a detailed
numerical comparison of our predictions with the available data on the
transverse-momentum distribution in Z-boson production at the Tevatron and LHC.
| [
{
"created": "Tue, 27 Sep 2011 20:19:30 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Becher",
"Thomas",
""
],
[
"Neubert",
"Matthias",
""
],
[
"Wilhelm",
"Daniel",
""
]
] | Using methods from effective field theory, we develop a novel, systematic framework for the calculation of the cross sections for electroweak gauge-boson production at small and very small transverse momentum q_T, in which large logarithms of the scale ratio M_V/q_T are resummed to all orders. These cross sections receive logarithmically enhanced corrections from two sources: the running of the hard matching coefficient and the collinear factorization anomaly. The anomaly leads to the dynamical generation of a non-perturbative scale q_* ~ M_V e^{-const/\alpha_s(M_V)}, which protects the processes from receiving large long-distance hadronic contributions. Expanding the cross sections in either \alpha_s or q_T generates strongly divergent series, which must be resummed. As a by-product, we obtain an explicit non-perturbative expression for the intercept of the cross sections at q_T=0, including the normalization and first-order \alpha_s(q_*) correction. We perform a detailed numerical comparison of our predictions with the available data on the transverse-momentum distribution in Z-boson production at the Tevatron and LHC. |
hep-ph/9605423 | Abada | As. Abada, M.B. Gavela, O. P\`ene | To rescue a star | 10 pages, Latex2e, two figures | Phys.Lett. B387 (1996) 315-319 | 10.1016/0370-2693(96)01050-7 | LPTHE-Orsay 96/36, FTUAM FEV/96/22 | hep-ph astro-ph | null | Massless neutrinos are exchanged in a neutron star, leading to long range
interactions. Many body forces of this type follow and we resum them. Their net
contribution to the total energy is negligible as compared to the star mass.
The stability of the star is not in danger, contrary to recent assertions.
| [
{
"created": "Tue, 28 May 1996 18:03:38 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Abada",
"As.",
""
],
[
"Gavela",
"M. B.",
""
],
[
"Pène",
"O.",
""
]
] | Massless neutrinos are exchanged in a neutron star, leading to long range interactions. Many body forces of this type follow and we resum them. Their net contribution to the total energy is negligible as compared to the star mass. The stability of the star is not in danger, contrary to recent assertions. |
1304.6346 | Roberto Pittau | Roberto Pittau (Granada U., Theor. Phys. Astrophys. & CAFPE, Granada) | Quantum field theory in four dimensions | 10 pages, Proceedings of the Corfu Summer Institute 2012 "School and
Workshops on Elementary Particle Physics and Gravity" September 8-27, 2012,
Corfu, Greece | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I review the current status of FDR, the recently introduced Four-Dimensional
Regularization/Renormalization approach to ultraviolet divergences in Quantum
Field Theory. FDR also regulates infrared and collinear infinities in the
intermediate steps of the calculation.
| [
{
"created": "Tue, 23 Apr 2013 16:48:04 GMT",
"version": "v1"
}
] | 2013-04-24 | [
[
"Pittau",
"Roberto",
"",
"Granada U., Theor. Phys. Astrophys. & CAFPE, Granada"
]
] | I review the current status of FDR, the recently introduced Four-Dimensional Regularization/Renormalization approach to ultraviolet divergences in Quantum Field Theory. FDR also regulates infrared and collinear infinities in the intermediate steps of the calculation. |
1802.07826 | Yoshimasa Kurihara | Junpei Fujimoto and Yoshimasa Kurihara and Nhi M. U. Quach | $\mathcal{O}(\alpha^2)$ ISR effects with a full electroweak one-loop
correction for a top pair-production at the ILC | Comments: 12 pages, 5 figures. Prepared for JHEP. Portions of this
work previously appeared as arXiv:1706.07042, on which this heavily draws | null | 10.1140/epjc/s10052-019-7026-7 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Precise predictions for an $e^+e^-\rightarrow t\bar{t}$ cross section are
presented at an energy region from 400 GeV to 800 GeV. Cross sections are
estimated including the beam-polarization effects with full
$\mathcal{O}(\alpha)$, and also with effects of the initial-state photon
emission. A radiator technique is used for the initial-state photon emission up
to two-loop order. A weak correction is defined as the full electroweak
corrections without the initial-state photonic corrections. As a result, it is
obtained that the total cross section of a top quark pair-production receives
the weak corrections of $+4\%$ over the trivial initial state corrections at a
centre of mass energy of 500 GeV. Among the initial state contributions, a
contribution from two-loop diagrams gives less than $0.11\%$ correction over
the one-loop ones at the center of mass energies of from $400$ GeV to $800$
GeV. In addition, an effect of a running coupling constant is also discussed.
| [
{
"created": "Wed, 21 Feb 2018 21:58:28 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Feb 2018 04:32:52 GMT",
"version": "v2"
}
] | 2019-07-24 | [
[
"Fujimoto",
"Junpei",
""
],
[
"Kurihara",
"Yoshimasa",
""
],
[
"Quach",
"Nhi M. U.",
""
]
] | Precise predictions for an $e^+e^-\rightarrow t\bar{t}$ cross section are presented at an energy region from 400 GeV to 800 GeV. Cross sections are estimated including the beam-polarization effects with full $\mathcal{O}(\alpha)$, and also with effects of the initial-state photon emission. A radiator technique is used for the initial-state photon emission up to two-loop order. A weak correction is defined as the full electroweak corrections without the initial-state photonic corrections. As a result, it is obtained that the total cross section of a top quark pair-production receives the weak corrections of $+4\%$ over the trivial initial state corrections at a centre of mass energy of 500 GeV. Among the initial state contributions, a contribution from two-loop diagrams gives less than $0.11\%$ correction over the one-loop ones at the center of mass energies of from $400$ GeV to $800$ GeV. In addition, an effect of a running coupling constant is also discussed. |
2301.05959 | Parham Dehghani | Parham Dehghani, Mariana Frank | Reconciling collider signals, dark matter, and the muon anomalous
magnetic moment in the supersymmetric $ U(1)_{R}\times U(1)_{B-L}$ model | 52 pages, 18 figures, 14 tables | JHEP06 (2023) 001 | 10.1007/JHEP06(2023)001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the low-scale predictions of the supersymmetric model extended by
$U(1)_R \times U(1)_{B-L}$ symmetry, obtained by breaking $SO(10)$ symmetry at
GUT scale via a left-right supersymmetric model. Two new singlet Higgs fields
($\chi_R$, $\bar{\chi}_R$) are responsible for the $U(1)_R \times U(1)_{B-L}$
symmetry breaking to the standard model gauge group. We explore the
phenomenology of this model by assuming universal and non-universal boundary
conditions at the GUT scale and their effects in obtaining consistency among
low-energy observables, dark matter experiments, muon magnetic moment
measurements, and $Z^{\prime}$ phenomenology. We examine different scenarios
with both the lightest neutralino and sneutrino mass eigenstates as the dark
matter candidates that satisfy all the experimental constraints. We explore the
collider signals of various scenarios including different benchmarks and their
significance versus standard model background. To complement our analysis, we
perform recasting of several LHC analyses to verify the credibility of
different benchmarks. We find that relaxing the universality conditions at
$M_{\rm GUT}$ can significantly improve the agreement of the model against the
experimental bounds. While the muon anomalous magnetic moment is found to be
the most challenging observable to fit with the model, we find points in the
parameter space consistent within $2 \sigma$ from the average measured value,
employing non-universality at the GUT scale.
| [
{
"created": "Sat, 14 Jan 2023 18:15:36 GMT",
"version": "v1"
},
{
"created": "Sun, 4 Jun 2023 13:49:47 GMT",
"version": "v2"
}
] | 2023-06-06 | [
[
"Dehghani",
"Parham",
""
],
[
"Frank",
"Mariana",
""
]
] | We study the low-scale predictions of the supersymmetric model extended by $U(1)_R \times U(1)_{B-L}$ symmetry, obtained by breaking $SO(10)$ symmetry at GUT scale via a left-right supersymmetric model. Two new singlet Higgs fields ($\chi_R$, $\bar{\chi}_R$) are responsible for the $U(1)_R \times U(1)_{B-L}$ symmetry breaking to the standard model gauge group. We explore the phenomenology of this model by assuming universal and non-universal boundary conditions at the GUT scale and their effects in obtaining consistency among low-energy observables, dark matter experiments, muon magnetic moment measurements, and $Z^{\prime}$ phenomenology. We examine different scenarios with both the lightest neutralino and sneutrino mass eigenstates as the dark matter candidates that satisfy all the experimental constraints. We explore the collider signals of various scenarios including different benchmarks and their significance versus standard model background. To complement our analysis, we perform recasting of several LHC analyses to verify the credibility of different benchmarks. We find that relaxing the universality conditions at $M_{\rm GUT}$ can significantly improve the agreement of the model against the experimental bounds. While the muon anomalous magnetic moment is found to be the most challenging observable to fit with the model, we find points in the parameter space consistent within $2 \sigma$ from the average measured value, employing non-universality at the GUT scale. |
2207.14662 | Hiroto Shibuya | Hiroto Shibuya, Takashi Toma | Impact of first-order phase transitions on dark matter production in the
scotogenic model | 28 pages, 11 figures, version to appear in JHEP | JHEP 11 (2022) 064 | 10.1007/JHEP11(2022)064 | KANAZAWA-22-04 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we investigate the effects of first-order phase transitions on
the singlet fermionic dark matter in the scotogenic model. It is known that
this dark matter candidate tends to conflict with the relevant constraints such
as the neutrino oscillation data and charged lepton flavor violating processes
if its thermal production mechanism is assumed. We find that the dark matter
production mechanisms are modified by first-order phase transitions at some
specific parameter regions, where the phase transitions can be one-step or
two-step depending on the parameters. If the phase transition is one-step, a
sufficiently low nucleation temperature is required to reproduce the observed
relic abundance of dark matter. If the phase transition is two-step, the dark
matter should never be thermalized, otherwise the abundance would remain too
much and overclose the universe. This is because the nucleation temperature
cannot be low as in the one-step case. Therefore we require another way of dark
matter production, the freeze-in mechanism for the two-step case. We show that
the freeze-in mechanism is modified by the temporary vacuum expectation value
of the inert scalar field. In both cases, the first-order phase transitions
could produce observable gravitational wave spectra. In particular for the
one-step phase transition, the generated gravitational waves with sizable
energy density are intrinsically correlated with the dark matter production
mechanism, and can be detectable by future space-based interferometers.
| [
{
"created": "Fri, 29 Jul 2022 13:08:32 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Nov 2022 04:32:34 GMT",
"version": "v2"
}
] | 2022-11-17 | [
[
"Shibuya",
"Hiroto",
""
],
[
"Toma",
"Takashi",
""
]
] | In this work, we investigate the effects of first-order phase transitions on the singlet fermionic dark matter in the scotogenic model. It is known that this dark matter candidate tends to conflict with the relevant constraints such as the neutrino oscillation data and charged lepton flavor violating processes if its thermal production mechanism is assumed. We find that the dark matter production mechanisms are modified by first-order phase transitions at some specific parameter regions, where the phase transitions can be one-step or two-step depending on the parameters. If the phase transition is one-step, a sufficiently low nucleation temperature is required to reproduce the observed relic abundance of dark matter. If the phase transition is two-step, the dark matter should never be thermalized, otherwise the abundance would remain too much and overclose the universe. This is because the nucleation temperature cannot be low as in the one-step case. Therefore we require another way of dark matter production, the freeze-in mechanism for the two-step case. We show that the freeze-in mechanism is modified by the temporary vacuum expectation value of the inert scalar field. In both cases, the first-order phase transitions could produce observable gravitational wave spectra. In particular for the one-step phase transition, the generated gravitational waves with sizable energy density are intrinsically correlated with the dark matter production mechanism, and can be detectable by future space-based interferometers. |
hep-ph/0104107 | Aleksander Filip Zarnecki | A.F.Zarnecki | Contact Interactions, Large Extra Dimensions and Leptoquarks at THERA | 23 pages, 9 figures, 7 tables | Acta Phys.Polon. B33 (2002) 619-640 | null | null | hep-ph | null | The sensitivity of THERA to different models of "new physics" has been
studied, both for the contact interaction approximation and for the resonance
production. For contact interaction models conserving parity, scales up to
about 18 TeV can be explored at THERA, extending considerably beyond the
existing bounds. Significant improvement of existing limits is also expected
for models with large extra dimensions. Effective Plank mass scales up to about
2.8 TeV can be probed. THERA will be the best machine to study leptoquark
properties, for leptoquark masses up to about 1 TeV. It will be sensitive to
the leptoquark Yukawa couplings down to lambda ~ 0.01.
| [
{
"created": "Wed, 11 Apr 2001 12:16:58 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Zarnecki",
"A. F.",
""
]
] | The sensitivity of THERA to different models of "new physics" has been studied, both for the contact interaction approximation and for the resonance production. For contact interaction models conserving parity, scales up to about 18 TeV can be explored at THERA, extending considerably beyond the existing bounds. Significant improvement of existing limits is also expected for models with large extra dimensions. Effective Plank mass scales up to about 2.8 TeV can be probed. THERA will be the best machine to study leptoquark properties, for leptoquark masses up to about 1 TeV. It will be sensitive to the leptoquark Yukawa couplings down to lambda ~ 0.01. |
hep-ph/0010304 | J\'er\^ome Charles | J. Charles (IFAE-Barcelona & CPT-Marseille) and L. Oliver (LPT-Orsay) | Discrete ambiguities in the determination of the CP angles | Talk given by L. Oliver at the International Conference on CP
Violation Physics, September 18-22 2000, Ferrara, Italy (8 pages, 3 figures).
Report number added | Nucl.Phys.Proc.Suppl.99B:287-294,2001 | 10.1016/S0920-5632(01)01388-3 | UAB-FT-497, CPT-2000/PE.4073, LPT-Orsay 00-86 | hep-ph hep-ex | null | We review briefly the problem of the discrete ambiguities in the
determination of the CKM angles, by classifying them into different categories.
We then focus on cos(2beta) and the extraction of alpha using QCD
factorization.
| [
{
"created": "Thu, 26 Oct 2000 15:34:12 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Oct 2000 15:55:38 GMT",
"version": "v2"
}
] | 2010-11-23 | [
[
"Charles",
"J.",
"",
"IFAE-Barcelona & CPT-Marseille"
],
[
"Oliver",
"L.",
"",
"LPT-Orsay"
]
] | We review briefly the problem of the discrete ambiguities in the determination of the CKM angles, by classifying them into different categories. We then focus on cos(2beta) and the extraction of alpha using QCD factorization. |
hep-ph/9905397 | Galit Eyal | Gabriela Barenboim, Galit Eyal and Yosef Nir | Constraining New Physics with the CDF Measurement of CP Violation in $B
\to \psi K_S$ | 13 pages, harvmac, 3 figures; v2: a discussion of new physics effects
on tree level decays added; references added; accepted for publication in
Physical Review Letters | Phys.Rev.Lett.83:4486-4489,1999 | 10.1103/PhysRevLett.83.4486 | MZ-TH/99-19, WIS-99/21/MAY-DPP | hep-ph | null | Recently, the CDF collaboration has reported a measurement of the CP
asymmetry in the $B\to\psi K_S$ decay: $a_{\psi K_S}=0.79^{+0.41}_{-0.44}$. We
analyze the constraints that follow from this measurement on the size and the
phase of contributions from new physics to $B-\barB$ mixing. Defining the
relative phase between the full $M_{12}$ amplitude and the Standard Model
contribution to be $2\theta_d$, we find a new bound: $\sin2\theta_d\gsim-0.6
(-0.87)$ at one sigma (95% CL). Further implications for the CP asymmetry in
semileptonic B decays are discussed.
| [
{
"created": "Wed, 19 May 1999 13:53:04 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Oct 1999 19:30:01 GMT",
"version": "v2"
}
] | 2010-11-23 | [
[
"Barenboim",
"Gabriela",
""
],
[
"Eyal",
"Galit",
""
],
[
"Nir",
"Yosef",
""
]
] | Recently, the CDF collaboration has reported a measurement of the CP asymmetry in the $B\to\psi K_S$ decay: $a_{\psi K_S}=0.79^{+0.41}_{-0.44}$. We analyze the constraints that follow from this measurement on the size and the phase of contributions from new physics to $B-\barB$ mixing. Defining the relative phase between the full $M_{12}$ amplitude and the Standard Model contribution to be $2\theta_d$, we find a new bound: $\sin2\theta_d\gsim-0.6 (-0.87)$ at one sigma (95% CL). Further implications for the CP asymmetry in semileptonic B decays are discussed. |
1612.04383 | Farinaldo Queiroz | Alexandre Alves, Giorgio Arcadi, P. V. Dong, Laura Duarte, Farinaldo
S. Queiroz, Jos\'e W. F. Valle | R-parity as a residual gauge symmetry : probing a theory of cosmological
dark matter | 7 pages, 3 figures | null | 10.1016/j.physletb.2017.07.056 | IFIC/16-XX | hep-ph astro-ph.HE hep-ex hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a non-supersymmetric scenario in which the R-parity symmetry $R_P
= (-1)^{3(B-L)+2s}$ arises as a result of spontaneous gauge symmetry breaking,
leading to a viable Dirac fermion WIMP dark matter candidate. Direct detection
in nuclear recoil experiments probes dark matter masses around $2-5$ TeV for
$M_{Z^{\prime}} \sim 3-4$ TeV consistent with searches at the LHC, while lepton
flavor violation rates and flavor changing neutral currents in neutral meson
systems lie within reach of upcoming experiments.
| [
{
"created": "Tue, 13 Dec 2016 21:00:05 GMT",
"version": "v1"
}
] | 2017-10-11 | [
[
"Alves",
"Alexandre",
""
],
[
"Arcadi",
"Giorgio",
""
],
[
"Dong",
"P. V.",
""
],
[
"Duarte",
"Laura",
""
],
[
"Queiroz",
"Farinaldo S.",
""
],
[
"Valle",
"José W. F.",
""
]
] | We present a non-supersymmetric scenario in which the R-parity symmetry $R_P = (-1)^{3(B-L)+2s}$ arises as a result of spontaneous gauge symmetry breaking, leading to a viable Dirac fermion WIMP dark matter candidate. Direct detection in nuclear recoil experiments probes dark matter masses around $2-5$ TeV for $M_{Z^{\prime}} \sim 3-4$ TeV consistent with searches at the LHC, while lepton flavor violation rates and flavor changing neutral currents in neutral meson systems lie within reach of upcoming experiments. |
1911.02677 | Philipp Isserstedt | Philipp Isserstedt, Michael Buballa, Christian S. Fischer, Pascal J.
Gunkel | Dyson-Schwinger approach to baryon number fluctuations | 5 pages, 4 figures; contribution to the proceedings of the FAIR next
generation scientists workshop (FAIRNESS), 6th edition, 20-24 May 2019,
Arenzano, Italy | J. Phys. Conf. Ser. 1667, 012015 (2020) | 10.1088/1742-6596/1667/1/012015 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We summarize our results on baryon number fluctuations at nonzero temperature
and chemical potential. They are obtained from solutions of a coupled set of
Dyson-Schwinger equations for the quark and gluon propagators of QCD in Landau
gauge with $N_f=2+1$ quark flavors. In comparison with preliminary STAR data,
our results are compatible with a critical endpoint at large chemical potential
and a freeze-out line that bends below it.
| [
{
"created": "Wed, 6 Nov 2019 23:30:17 GMT",
"version": "v1"
}
] | 2020-11-26 | [
[
"Isserstedt",
"Philipp",
""
],
[
"Buballa",
"Michael",
""
],
[
"Fischer",
"Christian S.",
""
],
[
"Gunkel",
"Pascal J.",
""
]
] | We summarize our results on baryon number fluctuations at nonzero temperature and chemical potential. They are obtained from solutions of a coupled set of Dyson-Schwinger equations for the quark and gluon propagators of QCD in Landau gauge with $N_f=2+1$ quark flavors. In comparison with preliminary STAR data, our results are compatible with a critical endpoint at large chemical potential and a freeze-out line that bends below it. |
hep-ph/9508238 | Fontannaz | Michel Fontannaz | Beyond Leading Logarithm Parton Distributions in the photon | 17 p., TEX file (figs 5 to 10 are available from the author) | null | null | Preprint LPTHE Orsay 95-05 | hep-ph | null | I discuss the parton distributions in the photon and the constraints coming
from the jet production in photoproduction and in photon-photon collisions.
| [
{
"created": "Fri, 4 Aug 1995 16:53:29 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Fontannaz",
"Michel",
""
]
] | I discuss the parton distributions in the photon and the constraints coming from the jet production in photoproduction and in photon-photon collisions. |
hep-ph/0412149 | Yu-Ping Kuang | Bin Zhang, Yuanning Gao, Yu-Ping Kuang | Distinguishing technicolor models via tt-bar productions at polarized
photon colliders | 7 pages, 6 figures, to appear in Physical Review D | Phys.Rev.D70:115012,2004 | 10.1103/PhysRevD.70.115012 | TUHEP-TH-03142 | hep-ph | null | We study top quark pair productions at a polarized photon collider from an
e(+)e(-) linear collider (LC) in various improved technicolor model, namely,
the one-family walking technicolor model, the top-color-assisted technicolor
model, and the top-color-assisted multiscale technicolor model. Recent
constraint on the top-pion mass from the precision data of R(b) is considered.
It is shown that, considering only the statistical errors, a polarized photon
collider from a 500 GeV LC with an integrated luminosity of 500 inverse fb is
sufficient for distinguishing the three improved technicolor models
experimentally.
| [
{
"created": "Sat, 11 Dec 2004 10:12:38 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Zhang",
"Bin",
""
],
[
"Gao",
"Yuanning",
""
],
[
"Kuang",
"Yu-Ping",
""
]
] | We study top quark pair productions at a polarized photon collider from an e(+)e(-) linear collider (LC) in various improved technicolor model, namely, the one-family walking technicolor model, the top-color-assisted technicolor model, and the top-color-assisted multiscale technicolor model. Recent constraint on the top-pion mass from the precision data of R(b) is considered. It is shown that, considering only the statistical errors, a polarized photon collider from a 500 GeV LC with an integrated luminosity of 500 inverse fb is sufficient for distinguishing the three improved technicolor models experimentally. |
2003.00101 | Noah Kurinsky | Noah Kurinsky, Daniel Baxter, Yonatan Kahn, Gordan Krnjaic, Peter
Abbamonte | Reply to Robinson and Michaud, arXiv:2002.08893 | 4 Pages | null | null | null | hep-ph astro-ph.CO cond-mat.mtrl-sci hep-ex physics.ins-det | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We respond to Robinson and Michaud's (RM) comment (arXiv:2002.08893) on our
recent preprint arXiv:2002.06937, in which we discuss recent excesses in
low-threshold dark matter searches, and offer a potential unifying dark matter
interpretation. We thank RM for their feedback, which highlights the critical
need for future measurements to directly calibrate plasmon charge yields for
low $\sim$ 10 eV energy depositions. RM objected to our assertion that plasmons
generated at energy scales below 100~eV may have a large branching fraction
into phonons. As we argue below, the points raised by RM do not invalidate our
primary conclusions, as they pertain to a much different energy scale than we
discuss in our paper.
| [
{
"created": "Fri, 28 Feb 2020 22:45:56 GMT",
"version": "v1"
}
] | 2020-03-03 | [
[
"Kurinsky",
"Noah",
""
],
[
"Baxter",
"Daniel",
""
],
[
"Kahn",
"Yonatan",
""
],
[
"Krnjaic",
"Gordan",
""
],
[
"Abbamonte",
"Peter",
""
]
] | We respond to Robinson and Michaud's (RM) comment (arXiv:2002.08893) on our recent preprint arXiv:2002.06937, in which we discuss recent excesses in low-threshold dark matter searches, and offer a potential unifying dark matter interpretation. We thank RM for their feedback, which highlights the critical need for future measurements to directly calibrate plasmon charge yields for low $\sim$ 10 eV energy depositions. RM objected to our assertion that plasmons generated at energy scales below 100~eV may have a large branching fraction into phonons. As we argue below, the points raised by RM do not invalidate our primary conclusions, as they pertain to a much different energy scale than we discuss in our paper. |
2112.14759 | Martin Rosenlyst | Martin Rosenlyst | Composite self-interacting dark matter and Higgs | 12 pages, 1 figure, 1 table | null | 10.1016/j.physletb.2022.137369 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a novel mechanism in composite models that provides
self-interacting dark matter along with the Higgs itself as composite
particles, alleviating the Standard Model naturalness problem and explaining
small-scale discrepancies such as the core-cusp and "too big to fail" problems.
These dark matter candidates are stable due to global U(1) symmetries of the
composite dynamics and their strong self-interactions are created by the novel
mechanism based on top-quark partial compositeness. The relic density of the
dark matter candidates is particle anti-particle symmetric and due to thermal
freeze-out. We implement this mechanism in a four-dimensional gauge theory with
a minimal number of fermions charged under a new confining gauge group
$G_{\text{HC}} $.
| [
{
"created": "Wed, 29 Dec 2021 18:57:30 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Dec 2021 16:41:27 GMT",
"version": "v2"
}
] | 2022-08-10 | [
[
"Rosenlyst",
"Martin",
""
]
] | We propose a novel mechanism in composite models that provides self-interacting dark matter along with the Higgs itself as composite particles, alleviating the Standard Model naturalness problem and explaining small-scale discrepancies such as the core-cusp and "too big to fail" problems. These dark matter candidates are stable due to global U(1) symmetries of the composite dynamics and their strong self-interactions are created by the novel mechanism based on top-quark partial compositeness. The relic density of the dark matter candidates is particle anti-particle symmetric and due to thermal freeze-out. We implement this mechanism in a four-dimensional gauge theory with a minimal number of fermions charged under a new confining gauge group $G_{\text{HC}} $. |
1107.4226 | Martin Schumacher | Martin Schumacher | Conference Report: Structure of scalar mesons and the Higgs sector of
strong interaction | XIV International Conference on Hadron Spectroscopy
(hadron2011),13-17 June 2011,Munich,Germany | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $\sigma$ mesons may be considered as the Higgs boson of strong
interaction. While the observation of the electroweak Higgs boson is the
primary goal in ongoing experiments at the LHC, the $\sigma$ meson is by now
well studied both as an on-shell particle and as a virtual particle while being
part of the constituent quark. This makes it timely to give an overview of the
present status of the Higgs sector of strong interaction which includes the
scalar mesons $\sigma(600)$, $\kappa(800)$, $f_0(980)$ and $a_0(980)$ together
with the pseudo Goldstone bosons $\pi$, $K$ and $\eta$.
| [
{
"created": "Thu, 21 Jul 2011 10:18:36 GMT",
"version": "v1"
}
] | 2011-07-22 | [
[
"Schumacher",
"Martin",
""
]
] | The $\sigma$ mesons may be considered as the Higgs boson of strong interaction. While the observation of the electroweak Higgs boson is the primary goal in ongoing experiments at the LHC, the $\sigma$ meson is by now well studied both as an on-shell particle and as a virtual particle while being part of the constituent quark. This makes it timely to give an overview of the present status of the Higgs sector of strong interaction which includes the scalar mesons $\sigma(600)$, $\kappa(800)$, $f_0(980)$ and $a_0(980)$ together with the pseudo Goldstone bosons $\pi$, $K$ and $\eta$. |
2003.04156 | Michal Krelina | Michal Krelina and Jan Nemchik | Nuclear shadowing in DIS at electron-ion colliders | Datasets at https://zenodo.org/record/3470138 , fixed figure and
misprints | Eur. Phys. J. Plus 135, 444 (2020) | 10.1140/epjp/s13360-020-00498-2 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a revision of predictions for nuclear shadowing in deep-inelastic
scattering at small Bjorken $x_{Bj}$ corresponding to kinematic regions
accessible by the future experiments at electron-ion colliders. The nuclear
shadowing is treated within the color dipole formalism based on the rigorous
Green function technique. This allows incorporating naturally color
transparency and coherence length effects, which are not consistently and
properly included in present calculations. For the lowest $|q\bar q\rangle$
Fock component of the photon, our calculations are based on an exact numerical
solution of the evolution equation for the Green function. Here the magnitude
of shadowing is tested using a realistic form for the nuclear density function,
as well as various phenomenological models for the dipole cross section. The
corresponding variation of the transverse size of the $q\bar q$ photon
fluctuations is important for $x_{Bj}\gtrsim 10^{-4}$, on the contrary with the
most of other models, which use frequently only the eikonal approximation with
the "frozen" transverse size. At $x_{Bj}\lesssim 0.01$ we calculate within the
same formalism also a shadowing correction for the higher Fock component of the
photon containing gluons. The corresponding magnitudes of gluon shadowing
correction are compared adopting different phenomenological dipole models. Our
results are tested by available data from the E665 and NMC collaborations.
Finally, the magnitude of nuclear shadowing is predicted for various kinematic
regions that should be scanned by the future experiments at electron-ion
colliders.
| [
{
"created": "Mon, 9 Mar 2020 14:02:45 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Mar 2020 14:57:37 GMT",
"version": "v2"
}
] | 2020-06-11 | [
[
"Krelina",
"Michal",
""
],
[
"Nemchik",
"Jan",
""
]
] | We present a revision of predictions for nuclear shadowing in deep-inelastic scattering at small Bjorken $x_{Bj}$ corresponding to kinematic regions accessible by the future experiments at electron-ion colliders. The nuclear shadowing is treated within the color dipole formalism based on the rigorous Green function technique. This allows incorporating naturally color transparency and coherence length effects, which are not consistently and properly included in present calculations. For the lowest $|q\bar q\rangle$ Fock component of the photon, our calculations are based on an exact numerical solution of the evolution equation for the Green function. Here the magnitude of shadowing is tested using a realistic form for the nuclear density function, as well as various phenomenological models for the dipole cross section. The corresponding variation of the transverse size of the $q\bar q$ photon fluctuations is important for $x_{Bj}\gtrsim 10^{-4}$, on the contrary with the most of other models, which use frequently only the eikonal approximation with the "frozen" transverse size. At $x_{Bj}\lesssim 0.01$ we calculate within the same formalism also a shadowing correction for the higher Fock component of the photon containing gluons. The corresponding magnitudes of gluon shadowing correction are compared adopting different phenomenological dipole models. Our results are tested by available data from the E665 and NMC collaborations. Finally, the magnitude of nuclear shadowing is predicted for various kinematic regions that should be scanned by the future experiments at electron-ion colliders. |
1112.5527 | Rui Santos | Abdesslam Arhrib, Cheng-Wei Chiang, Dilip Kumar Ghosh and Rui Santos | Two Higgs Doublet Model in light of the Standard Model H -> tau^+ tau^-
search at the LHC | 23 pages, 31 figures | null | 10.1103/PhysRevD.85.115003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the implications of the searches based on H -> tau^+ tau^- by the
ATLAS and CMS collaborations on the parameter space of the two Higgs doublet
model (2HDM). In the 2HDM, the scalars can decay into a tau pair with a
branching ratio larger than the SM one, leading to constraints on the 2HDM
parameter space. We have also discussed the implications for the 2HDM of the
recent di-muon search by the ATLAS collaboration for a CP-odd scalar in the
mass range 4-12 GeV.
| [
{
"created": "Fri, 23 Dec 2011 08:13:02 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Apr 2012 21:16:22 GMT",
"version": "v2"
}
] | 2013-05-30 | [
[
"Arhrib",
"Abdesslam",
""
],
[
"Chiang",
"Cheng-Wei",
""
],
[
"Ghosh",
"Dilip Kumar",
""
],
[
"Santos",
"Rui",
""
]
] | We study the implications of the searches based on H -> tau^+ tau^- by the ATLAS and CMS collaborations on the parameter space of the two Higgs doublet model (2HDM). In the 2HDM, the scalars can decay into a tau pair with a branching ratio larger than the SM one, leading to constraints on the 2HDM parameter space. We have also discussed the implications for the 2HDM of the recent di-muon search by the ATLAS collaboration for a CP-odd scalar in the mass range 4-12 GeV. |
0803.2393 | Yong-Yeon Keum | Yong-Yeon Keum, Kiyotomo Ichiki and Taka Kajino | Neutrino Mass Bounds from Neutrinoless Double Beta Decays and Large
Scale Structures | Latex 12 pages, 3 figures, correct typos and add new references | AIP Conf.Proc.1016:343-349,2008 | 10.1063/1.2943596 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the way how the total mass sum of neutrinos can be constrained
from the neutrinoless double beta decay and cosmological probes with cosmic
microwave background (WMAP 3-year results), large scale structures including
2dFGRS and SDSS data sets. First we discuss, in brief, on the current status of
neutrino mass bounds from neutrino beta decays and cosmic constrain within the
flat $\Lambda CMD$ model. In addition, we explore the interacting neutrino
dark-energy model, where the evolution of neutrino masses is determined by
quintessence scalar filed, which is responsable for cosmic acceleration today.
Assuming the flatness of the universe, the constraint we can derive from the
current observation is $\sum m_{\nu} < 0.87$eV at the 95 % confidence level,
which is consistent with $\sum m_{\nu} < 0.68$eV in the flat $\Lambda CDM$
model. Finally we discuss the future prospect of the neutrino mass bound with
weak-lensing effects.
| [
{
"created": "Mon, 17 Mar 2008 06:09:43 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Mar 2008 17:51:07 GMT",
"version": "v2"
}
] | 2010-12-13 | [
[
"Keum",
"Yong-Yeon",
""
],
[
"Ichiki",
"Kiyotomo",
""
],
[
"Kajino",
"Taka",
""
]
] | We investigate the way how the total mass sum of neutrinos can be constrained from the neutrinoless double beta decay and cosmological probes with cosmic microwave background (WMAP 3-year results), large scale structures including 2dFGRS and SDSS data sets. First we discuss, in brief, on the current status of neutrino mass bounds from neutrino beta decays and cosmic constrain within the flat $\Lambda CMD$ model. In addition, we explore the interacting neutrino dark-energy model, where the evolution of neutrino masses is determined by quintessence scalar filed, which is responsable for cosmic acceleration today. Assuming the flatness of the universe, the constraint we can derive from the current observation is $\sum m_{\nu} < 0.87$eV at the 95 % confidence level, which is consistent with $\sum m_{\nu} < 0.68$eV in the flat $\Lambda CDM$ model. Finally we discuss the future prospect of the neutrino mass bound with weak-lensing effects. |
hep-ph/9809426 | Yasunori Nomura | K. Hamaguchi, Yasunori Nomura, and T. Yanagida | Long Lived Superheavy Dark Matter with Discrete Gauge Symmetries | 27 pages, Latex | Phys.Rev.D59:063507,1999 | 10.1103/PhysRevD.59.063507 | UT-825 | hep-ph astro-ph | null | The recently observed ultra-high energy (UHE) cosmic rays beyond the
Greisen-Zatsepin-Kuzmin bound can be explained by the decays of some superheavy
$X$ particles forming a part of dark matter in our universe. We consider
various discrete gauge symmetries ${\bf Z}_N$ to ensure the required long
lifetime ($\tau_X \simeq 10^{10}-10^{22} years$) of the $X$ particle to explain
the UHE cosmic rays in the minimal supersymmetric standard model (MSSM) with
massive Majorana neutrinos. We show that there is no anomaly-free discrete
gauge symmetry to make the lifetime of the $X$ particle sufficiently long in
the MSSM with the $X$ particle. We find, however, possible solutions to this
problem especially by enlarging the particle contents in the MSSM. We show a
number of solutions introducing an extra pair of singlets $Y$ and $\bar{Y}$
which have fractional ${\bf Z}_N$ (N=2,3) charges. The present experimental
constraints on the $X$ particle are briefly discussed.
| [
{
"created": "Thu, 17 Sep 1998 08:13:15 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Jan 1999 03:12:20 GMT",
"version": "v2"
}
] | 2009-09-29 | [
[
"Hamaguchi",
"K.",
""
],
[
"Nomura",
"Yasunori",
""
],
[
"Yanagida",
"T.",
""
]
] | The recently observed ultra-high energy (UHE) cosmic rays beyond the Greisen-Zatsepin-Kuzmin bound can be explained by the decays of some superheavy $X$ particles forming a part of dark matter in our universe. We consider various discrete gauge symmetries ${\bf Z}_N$ to ensure the required long lifetime ($\tau_X \simeq 10^{10}-10^{22} years$) of the $X$ particle to explain the UHE cosmic rays in the minimal supersymmetric standard model (MSSM) with massive Majorana neutrinos. We show that there is no anomaly-free discrete gauge symmetry to make the lifetime of the $X$ particle sufficiently long in the MSSM with the $X$ particle. We find, however, possible solutions to this problem especially by enlarging the particle contents in the MSSM. We show a number of solutions introducing an extra pair of singlets $Y$ and $\bar{Y}$ which have fractional ${\bf Z}_N$ (N=2,3) charges. The present experimental constraints on the $X$ particle are briefly discussed. |
1609.09072 | Yonatan Kahn | Yonatan Kahn, Gordan Krnjaic, Siddharth Mishra-Sharma, Tim M.P. Tait | Light Weakly Coupled Axial Forces: Models, Constraints, and Projections | 30 pages, 5 figures, 4 tables. v2: format changed to JHEP, typos
fixed, references added | null | 10.1007/JHEP05(2017)002 | FERMILAB-PUB-16-385-PPD, UCI-HEP-TR-2016-15, MITP/16-098, PUPT 2507 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the landscape of constraints on MeV-GeV scale, hidden U(1)
forces with nonzero axial-vector couplings to Standard Model fermions. While
the purely vector-coupled dark photon, which may arise from kinetic mixing, is
a well-motivated scenario, several MeV-scale anomalies motivate a theory with
axial couplings which can be UV-completed consistent with Standard Model gauge
invariance. Moreover, existing constraints on dark photons depend on products
of various combinations of axial and vector couplings, making it difficult to
isolate the effects of axial couplings for particular flavors of SM fermions.
We present a representative renormalizable, UV-complete model of a dark photon
with adjustable axial and vector couplings, discuss its general features, and
show how some UV constraints may be relaxed in a model with nonrenormalizable
Yukawa couplings at the expense of fine-tuning. We survey the existing
parameter space and the projected reach of planned experiments, briefly
commenting on the relevance of the allowed parameter space to low-energy
anomalies in pi^0 and 8-Be* decay.
| [
{
"created": "Wed, 28 Sep 2016 20:00:01 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Oct 2016 17:56:54 GMT",
"version": "v2"
}
] | 2017-05-24 | [
[
"Kahn",
"Yonatan",
""
],
[
"Krnjaic",
"Gordan",
""
],
[
"Mishra-Sharma",
"Siddharth",
""
],
[
"Tait",
"Tim M. P.",
""
]
] | We investigate the landscape of constraints on MeV-GeV scale, hidden U(1) forces with nonzero axial-vector couplings to Standard Model fermions. While the purely vector-coupled dark photon, which may arise from kinetic mixing, is a well-motivated scenario, several MeV-scale anomalies motivate a theory with axial couplings which can be UV-completed consistent with Standard Model gauge invariance. Moreover, existing constraints on dark photons depend on products of various combinations of axial and vector couplings, making it difficult to isolate the effects of axial couplings for particular flavors of SM fermions. We present a representative renormalizable, UV-complete model of a dark photon with adjustable axial and vector couplings, discuss its general features, and show how some UV constraints may be relaxed in a model with nonrenormalizable Yukawa couplings at the expense of fine-tuning. We survey the existing parameter space and the projected reach of planned experiments, briefly commenting on the relevance of the allowed parameter space to low-energy anomalies in pi^0 and 8-Be* decay. |
hep-ph/0507069 | Le Ninh Duc | Le Duc Ninh and Hoang Ngoc Long | Standard-model-like Higgs boson production at the CERN LHC in 3-3-1
model with right-handed neutrinos | 9 pages, 6 figures | Phys.Rev.D72:075004,2005 | 10.1103/PhysRevD.72.075004 | null | hep-ph | null | The models based on ${SU}(3)_C\otimes {SU}(3)_L \otimes {U}(1)_X$ gauge group
(3-3-1) contain new Higgs bosons and one of them is the SM-like Higgs boson
$h$. Production of this Higgs boson at $p p$ colliders in the framework of
3-3-1 model with right-handed neutrinos is calculated. We found that the
contribution of the real $Z^\prime$ to the process $pp\to hZ$ is nearly 60 fb
if $M_{Z^\prime}$ is about 1 TeV. The decay width and the branching ratios of
the $Z'$ extra neutral gauge boson are systematically discussed.
| [
{
"created": "Wed, 6 Jul 2005 12:21:43 GMT",
"version": "v1"
},
{
"created": "Thu, 13 Oct 2005 14:46:16 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Ninh",
"Le Duc",
""
],
[
"Long",
"Hoang Ngoc",
""
]
] | The models based on ${SU}(3)_C\otimes {SU}(3)_L \otimes {U}(1)_X$ gauge group (3-3-1) contain new Higgs bosons and one of them is the SM-like Higgs boson $h$. Production of this Higgs boson at $p p$ colliders in the framework of 3-3-1 model with right-handed neutrinos is calculated. We found that the contribution of the real $Z^\prime$ to the process $pp\to hZ$ is nearly 60 fb if $M_{Z^\prime}$ is about 1 TeV. The decay width and the branching ratios of the $Z'$ extra neutral gauge boson are systematically discussed. |
1708.08929 | Yonatan Kahn | Yonit Hochberg, Yonatan Kahn, Mariangela Lisanti, Kathryn M. Zurek,
Adolfo G. Grushin, Roni Ilan, Sinead M. Griffin, Zhen-Fei Liu, Sophie F.
Weber, and Jeffrey B. Neaton | Detection of sub-MeV Dark Matter with Three-Dimensional Dirac Materials | 24+25 pages, 4 appendices, 12 figures, 1 table. v2: references added | Phys. Rev. D 97, 015004 (2018) | 10.1103/PhysRevD.97.015004 | PUPT-2535 | hep-ph cond-mat.mtrl-sci cond-mat.str-el | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose the use of three-dimensional Dirac materials as targets for direct
detection of sub-MeV dark matter. Dirac materials are characterized by a linear
dispersion for low-energy electronic excitations, with a small band gap of
O(meV) if lattice symmetries are broken. Dark matter at the keV scale carrying
kinetic energy as small as a few meV can scatter and excite an electron across
the gap. Alternatively, bosonic dark matter as light as a few meV can be
absorbed by the electrons in the target. We develop the formalism for dark
matter scattering and absorption in Dirac materials and calculate the
experimental reach of these target materials. We find that Dirac materials can
play a crucial role in detecting dark matter in the keV to MeV mass range that
scatters with electrons via a kinetically mixed dark photon, as the dark photon
does not develop an in-medium effective mass. The same target materials provide
excellent sensitivity to absorption of light bosonic dark matter in the meV to
hundreds of meV mass range, superior to all other existing proposals when the
dark matter is a kinetically mixed dark photon.
| [
{
"created": "Tue, 29 Aug 2017 18:00:01 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Sep 2017 02:14:46 GMT",
"version": "v2"
}
] | 2018-01-17 | [
[
"Hochberg",
"Yonit",
""
],
[
"Kahn",
"Yonatan",
""
],
[
"Lisanti",
"Mariangela",
""
],
[
"Zurek",
"Kathryn M.",
""
],
[
"Grushin",
"Adolfo G.",
""
],
[
"Ilan",
"Roni",
""
],
[
"Griffin",
"Sinead M.",
""
]... | We propose the use of three-dimensional Dirac materials as targets for direct detection of sub-MeV dark matter. Dirac materials are characterized by a linear dispersion for low-energy electronic excitations, with a small band gap of O(meV) if lattice symmetries are broken. Dark matter at the keV scale carrying kinetic energy as small as a few meV can scatter and excite an electron across the gap. Alternatively, bosonic dark matter as light as a few meV can be absorbed by the electrons in the target. We develop the formalism for dark matter scattering and absorption in Dirac materials and calculate the experimental reach of these target materials. We find that Dirac materials can play a crucial role in detecting dark matter in the keV to MeV mass range that scatters with electrons via a kinetically mixed dark photon, as the dark photon does not develop an in-medium effective mass. The same target materials provide excellent sensitivity to absorption of light bosonic dark matter in the meV to hundreds of meV mass range, superior to all other existing proposals when the dark matter is a kinetically mixed dark photon. |
2012.09867 | J\'er\'emy Auffinger | J\'er\'emy Auffinger, Isabella Masina, Giorgio Orlando | Bounds on warm dark matter from Schwarzschild primordial black holes | 27 pages, 8 figures | Eur. Phys. J. Plus (2021) 136: 261 | 10.1140/epjp/s13360-021-01247-9 | null | hep-ph astro-ph.CO astro-ph.HE hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider light dark matter candidates originated from the evaporation of
Schwarzschild primordial black holes, with masses in the range $10^{-5}-10^9$
g. These candidates are beyond Standard Model particles with negligible
couplings to the other particles, so that they interact only gravitationally.
Belonging to the category of warm dark matter, they nevertheless spoil
structure formation, with a softer impact for increasing values of the
candidate spin. Requiring such candidates to fully account for the observed
dark matter, we find that the scenario of black hole domination is ruled out
for all spin values up to 2. For the scenario of radiation domination, we
derive upper limits on the parameter $\beta$ (the primordial black hole energy
density at formation over the radiation one), which are less stringent the
higher the candidate spin is.
| [
{
"created": "Thu, 17 Dec 2020 19:00:02 GMT",
"version": "v1"
},
{
"created": "Thu, 11 Mar 2021 10:51:28 GMT",
"version": "v2"
}
] | 2021-03-12 | [
[
"Auffinger",
"Jérémy",
""
],
[
"Masina",
"Isabella",
""
],
[
"Orlando",
"Giorgio",
""
]
] | We consider light dark matter candidates originated from the evaporation of Schwarzschild primordial black holes, with masses in the range $10^{-5}-10^9$ g. These candidates are beyond Standard Model particles with negligible couplings to the other particles, so that they interact only gravitationally. Belonging to the category of warm dark matter, they nevertheless spoil structure formation, with a softer impact for increasing values of the candidate spin. Requiring such candidates to fully account for the observed dark matter, we find that the scenario of black hole domination is ruled out for all spin values up to 2. For the scenario of radiation domination, we derive upper limits on the parameter $\beta$ (the primordial black hole energy density at formation over the radiation one), which are less stringent the higher the candidate spin is. |
hep-ph/0002142 | Fabrizio Gangemi | Fabrizio Gangemi | Anomalous quartic couplings in six-fermion processes at the Linear
Collider | LaTeX (using elsart.sty). 15 pages, 6 figures. Submitted to Nuclear
Physics B | null | null | FNT/T-00/01 | hep-ph | null | The dimension-four genuine anomalous quartic couplings are studied in
processes of six-fermion production via e+e- collisions. Complete tree-level
electroweak calculations are performed including initial-state-radiation and
beamstrahlung. The analysis of final-state distributions can be used to find
kinematical cuts to enhance the effects of anomalous couplings. For the
parameters of the custodial-symmetry-conserving anomalous couplings a
sensitivity in the range between 10^{-3} and 10^{-2} can be expected at 1 TeV.
| [
{
"created": "Mon, 14 Feb 2000 11:58:50 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Gangemi",
"Fabrizio",
""
]
] | The dimension-four genuine anomalous quartic couplings are studied in processes of six-fermion production via e+e- collisions. Complete tree-level electroweak calculations are performed including initial-state-radiation and beamstrahlung. The analysis of final-state distributions can be used to find kinematical cuts to enhance the effects of anomalous couplings. For the parameters of the custodial-symmetry-conserving anomalous couplings a sensitivity in the range between 10^{-3} and 10^{-2} can be expected at 1 TeV. |
hep-ph/0412116 | Olivier Leitner | Z.J. Ajaltouni (LPC, Universite Blaise Pascal), E. Conte (LPC,
Universite Blaise Pascal) and O. Leitner (ECT*) | $\Lambda_b$ Decays into $\Lambda$-Vector | 10 pages, 2 figures | Phys.Lett. B614 (2005) 165-173 | 10.1016/j.physletb.2005.04.014 | PCCF RI 0417, ECT*-04-22 | hep-ph | null | A complete study of the angular distributions of the processes, $\Lambda_b
\to {\Lambda} V(1^-)$, with $\Lambda \to p {\pi}^-$ and $V (J/{\Psi}) \to
{\ell}^+ {\ell}^-$ or $V ({\rho}^0,\omega) \to {\pi}^+ {\pi}^-,$ is performed.
Emphasis is put on the initial $\Lambda_b$ polarization produced in the
proton-proton collisions. The polarization density-matrices as well as angular
distributions are derived and help to construct T-odd observables which allow
us to perform tests of both Time-Reversal and CP violation.
| [
{
"created": "Wed, 8 Dec 2004 15:30:09 GMT",
"version": "v1"
}
] | 2010-04-05 | [
[
"Ajaltouni",
"Z. J.",
"",
"LPC, Universite Blaise Pascal"
],
[
"Conte",
"E.",
"",
"LPC,\n Universite Blaise Pascal"
],
[
"Leitner",
"O.",
"",
"ECT*"
]
] | A complete study of the angular distributions of the processes, $\Lambda_b \to {\Lambda} V(1^-)$, with $\Lambda \to p {\pi}^-$ and $V (J/{\Psi}) \to {\ell}^+ {\ell}^-$ or $V ({\rho}^0,\omega) \to {\pi}^+ {\pi}^-,$ is performed. Emphasis is put on the initial $\Lambda_b$ polarization produced in the proton-proton collisions. The polarization density-matrices as well as angular distributions are derived and help to construct T-odd observables which allow us to perform tests of both Time-Reversal and CP violation. |
1905.08699 | Ingolf Bischer | Ingolf Bischer, Werner Rodejohann | General Neutrino Interactions from an Effective Field Theory Perspective | 23+9 pages, published version after minor revisions | Nucl. Phys. B947 (2019) 114746 | 10.1016/j.nuclphysb.2019.114746 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | General Neutrino Interactions (GNI) are scalar, pseudoscalar, vector, axial
vector or tensor interactions of neutrinos with fermions, and generalise the
often studied neutrino Non-Standard Interactions (NSI). If GNI arise from heavy
new physics, they should be embeddable into effective field theory operators
that respect the Standard Model (SM) gauge symmetry. Therefore we consider a
full basis of gauge-invariant dimension-six operators involving SM fermions and
right-handed singlet neutrinos and map their Wilson coefficients onto GNI
parameters. In this embedding we discuss correlations of and bounds on
different GNI in the context of charged lepton flavour violation processes and
neutrino-fermion scattering, as well as beta decay and coherent
neutrino-nucleus scattering. We also study possible UV completions of the
relevant dimension-six operators for GNI via leptoquarks that can be related to
radiative neutrino masses and $B$ physics anomalies. Details on the numbers of
free GNI parameters for Dirac or Majorana neutrinos and for CP violation or
conservation are also provided.
| [
{
"created": "Tue, 21 May 2019 15:29:09 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Sep 2019 11:47:50 GMT",
"version": "v2"
}
] | 2019-09-05 | [
[
"Bischer",
"Ingolf",
""
],
[
"Rodejohann",
"Werner",
""
]
] | General Neutrino Interactions (GNI) are scalar, pseudoscalar, vector, axial vector or tensor interactions of neutrinos with fermions, and generalise the often studied neutrino Non-Standard Interactions (NSI). If GNI arise from heavy new physics, they should be embeddable into effective field theory operators that respect the Standard Model (SM) gauge symmetry. Therefore we consider a full basis of gauge-invariant dimension-six operators involving SM fermions and right-handed singlet neutrinos and map their Wilson coefficients onto GNI parameters. In this embedding we discuss correlations of and bounds on different GNI in the context of charged lepton flavour violation processes and neutrino-fermion scattering, as well as beta decay and coherent neutrino-nucleus scattering. We also study possible UV completions of the relevant dimension-six operators for GNI via leptoquarks that can be related to radiative neutrino masses and $B$ physics anomalies. Details on the numbers of free GNI parameters for Dirac or Majorana neutrinos and for CP violation or conservation are also provided. |
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