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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1710.02129 | Anthony Bartolotta | Anthony Bartolotta, Michael J. Ramsey-Musolf | Coherent $\mu-e$ Conversion at Next-to-Leading Order | 36 pages, 2 figures, 7 tables | Phys. Rev. C 98, 015208 (2018) | 10.1103/PhysRevC.98.015208 | CALT-TH-2017-005, ACFI-T17-21 | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze next-to-leading order (NLO) corrections and uncertainties for
coherent $\mu-e$ conversion . The analysis is general but numerical results
focus on ${}^{27}\textrm{Al}$, which will be used in the Mu2E experiment. We
obtain a simple expression for the branching ratio in terms of Wilson
coefficients associated with possible physics beyond the Standard Model and a
set of model-independent parameters determined solely by Standard Model
dynamics. For scalar-mediated conversion, we find that NLO two-nucleon
contributions can significantly decrease the branching ratio, potentially
reducing the rate by as much as 50%. The pion-nucleon $\sigma$-term and quark
masses give the dominant sources of parametric uncertainty in this case. For
vector-mediated conversion, the impact of NLO contributions is considerably
less severe, while the present theoretical uncertainties are comparable to
parametric uncertainties.
| [
{
"created": "Thu, 5 Oct 2017 17:41:32 GMT",
"version": "v1"
}
] | 2018-08-01 | [
[
"Bartolotta",
"Anthony",
""
],
[
"Ramsey-Musolf",
"Michael J.",
""
]
] | We analyze next-to-leading order (NLO) corrections and uncertainties for coherent $\mu-e$ conversion . The analysis is general but numerical results focus on ${}^{27}\textrm{Al}$, which will be used in the Mu2E experiment. We obtain a simple expression for the branching ratio in terms of Wilson coefficients associated with possible physics beyond the Standard Model and a set of model-independent parameters determined solely by Standard Model dynamics. For scalar-mediated conversion, we find that NLO two-nucleon contributions can significantly decrease the branching ratio, potentially reducing the rate by as much as 50%. The pion-nucleon $\sigma$-term and quark masses give the dominant sources of parametric uncertainty in this case. For vector-mediated conversion, the impact of NLO contributions is considerably less severe, while the present theoretical uncertainties are comparable to parametric uncertainties. |
1108.4584 | Sergey Troshin | S.M. Troshin, N.E. Tyurin | Correlations in multiparticle production | 4 pages, 1 figure, contribution to the Proceedings of the 15th Annual
RDMS CMS Collaboration Conference Alushta (Crimea), Ukraine May 22 - 28, 2011 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss correlations in the hadron production in the $pp$-collision with
emphasize on the ridge-like structure origin in the two-particle correlation
function. We suggest that this structure can appear due to a rotating nature of
the transient state of matter generated in the intermidiate stage of proton
collison.
| [
{
"created": "Sun, 21 Aug 2011 08:47:19 GMT",
"version": "v1"
}
] | 2011-08-24 | [
[
"Troshin",
"S. M.",
""
],
[
"Tyurin",
"N. E.",
""
]
] | We discuss correlations in the hadron production in the $pp$-collision with emphasize on the ridge-like structure origin in the two-particle correlation function. We suggest that this structure can appear due to a rotating nature of the transient state of matter generated in the intermidiate stage of proton collison. |
2203.07883 | Wei Su | Ankit Beniwal, Filip Rajec, Markus Tobias Prim, Pat Scott, Wei Su,
Martin White, Anthony G. Williams, and Alex Woodcock | Global fit of 2HDM with future collider results | 9 pages, 3 plots, contribution to Snowmass 2021 | null | null | KIAS--P22014, gambit-proceedings-2022 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this work, we summarize a global fit study of Type-II two Higgs doublet
models (2HDM), and explore the impact of future SM-like Higgs and Z-pole
precision measurements on the allowed parameter space. The work is based on the
study results of a global fit of 2HDMs with the tool GAMBIT, utilising various
current constraints including theoretical constraints (unitarity,
perturbativity and vacuum stability), Higgs searches at colliders, electroweak
physics and flavour constraints. We further investigate the ability of future
facilities, such as the HL-LHC, CEPC, ILC and FCC-ee to explore the 2HDM
parameter space.
| [
{
"created": "Tue, 15 Mar 2022 13:32:44 GMT",
"version": "v1"
}
] | 2022-06-01 | [
[
"Beniwal",
"Ankit",
""
],
[
"Rajec",
"Filip",
""
],
[
"Prim",
"Markus Tobias",
""
],
[
"Scott",
"Pat",
""
],
[
"Su",
"Wei",
""
],
[
"White",
"Martin",
""
],
[
"Williams",
"Anthony G.",
""
],
[
"Wood... | In this work, we summarize a global fit study of Type-II two Higgs doublet models (2HDM), and explore the impact of future SM-like Higgs and Z-pole precision measurements on the allowed parameter space. The work is based on the study results of a global fit of 2HDMs with the tool GAMBIT, utilising various current constraints including theoretical constraints (unitarity, perturbativity and vacuum stability), Higgs searches at colliders, electroweak physics and flavour constraints. We further investigate the ability of future facilities, such as the HL-LHC, CEPC, ILC and FCC-ee to explore the 2HDM parameter space. |
1005.2676 | Michael Baker | Michael J Baker, S.T. Tsou | The Rotating Mass Matrix, the Strong CP Problem and Higgs Decay | 15 pages, 6 figures; improvements to introduction and preliminaries | Eur.Phys.J.C70:1009-1015,2010 | 10.1140/epjc/s10052-010-1506-0 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate a recent solution to the strong CP problem, obtaining a
theta-angle of order unity, and show that a smooth trajectory of the massive
eigenvector of a rank-one rotating mass matrix is consistent with the
experimental data for both fermion masses and mixing angles (except for the
masses of the lightest quarks). Using this trajectory we study Higgs decay and
find suppression of $\Gamma(H\to c\bar{c})$ compared to the standard model
predictions for a range of Higgs masses. We also give limits for flavour
violating decays, including a relatively large branching ratio for the
$\tau^-\mu^+$ mode.
| [
{
"created": "Sat, 15 May 2010 14:11:48 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Sep 2010 15:16:33 GMT",
"version": "v2"
}
] | 2012-01-25 | [
[
"Baker",
"Michael J",
""
],
[
"Tsou",
"S. T.",
""
]
] | We investigate a recent solution to the strong CP problem, obtaining a theta-angle of order unity, and show that a smooth trajectory of the massive eigenvector of a rank-one rotating mass matrix is consistent with the experimental data for both fermion masses and mixing angles (except for the masses of the lightest quarks). Using this trajectory we study Higgs decay and find suppression of $\Gamma(H\to c\bar{c})$ compared to the standard model predictions for a range of Higgs masses. We also give limits for flavour violating decays, including a relatively large branching ratio for the $\tau^-\mu^+$ mode. |
2105.01093 | Sayan Dasgupta | Avik Banerjee, Sayan Dasgupta, Tirtha Sankar Ray | Probing composite Higgs boson substructure at the HL-LHC | 18 pages, 7 captioned figures, Title changed, Conclusions unchanged,
Matches published version | Phys. Rev. D 104, 095021 (2021) | 10.1103/PhysRevD.104.095021 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Higgs boson may well be a composite scalar with a finite extension in
space. Owing to the momentum dependence of its couplings the imprints of such a
composite pseudo Goldstone Higgs may show up in the tails of various kinematic
distributions at the LHC, distinguishing it from an elementary state. From the
bottom up we construct the momentum dependent form factors to capture the
interactions of the composite Higgs with the weak gauge bosons. We demonstrate
their impact in the differential distributions of various kinematic parameters
for the $pp\rightarrow Z^*H\rightarrow l^+l^-b\bar{b}$ channel. We show that
this channel can provide an important handle to probe the Higgs' substructure
at the HL-LHC.
| [
{
"created": "Mon, 3 May 2021 18:01:10 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Dec 2021 16:46:37 GMT",
"version": "v2"
}
] | 2021-12-02 | [
[
"Banerjee",
"Avik",
""
],
[
"Dasgupta",
"Sayan",
""
],
[
"Ray",
"Tirtha Sankar",
""
]
] | The Higgs boson may well be a composite scalar with a finite extension in space. Owing to the momentum dependence of its couplings the imprints of such a composite pseudo Goldstone Higgs may show up in the tails of various kinematic distributions at the LHC, distinguishing it from an elementary state. From the bottom up we construct the momentum dependent form factors to capture the interactions of the composite Higgs with the weak gauge bosons. We demonstrate their impact in the differential distributions of various kinematic parameters for the $pp\rightarrow Z^*H\rightarrow l^+l^-b\bar{b}$ channel. We show that this channel can provide an important handle to probe the Higgs' substructure at the HL-LHC. |
2301.01408 | Spencer Klein | Spencer R. Klein | Challenges to the Good-Walker paradigm in coherent and incoherent
photoproduction | 7 pages; to be submitted for publication; comments are welcome | null | 10.1103/PhysRevC.107.055203 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | High-energy vector meson photoproduction is an important tool for studying
the partonic structure of matter at low Bjorken$-x$. In the Good-Walker (GW)
paradigm, the cross-section $d\sigma/dt$ for coherent production of vector
mesons or other final states, depends the average transverse distribution of
gluons, while the incoherent cross-section depends on fluctuations in the
nuclear structure, due to variations in nucleon positions, and/or gluonic hot
spots. However, predictions of the the GW paradigm seemingly conflict with data
from multiple experiments which observe coherent production of vector mesons
accompanied by nuclear excitation, or in peripheral relativistic heavy-ion
collisions. These data are consistent with a simpler, semi-classical approach.
We will discuss this contradiction and explore how and why GW fails. We will
also contrast the significant differences in incoherent photoproduction on
$^{197}$Au and $^{208}$Pb targets in the GW approach with the much smaller
expected differences in their low$-x$ gluon content.
| [
{
"created": "Wed, 4 Jan 2023 02:09:36 GMT",
"version": "v1"
}
] | 2023-05-31 | [
[
"Klein",
"Spencer R.",
""
]
] | High-energy vector meson photoproduction is an important tool for studying the partonic structure of matter at low Bjorken$-x$. In the Good-Walker (GW) paradigm, the cross-section $d\sigma/dt$ for coherent production of vector mesons or other final states, depends the average transverse distribution of gluons, while the incoherent cross-section depends on fluctuations in the nuclear structure, due to variations in nucleon positions, and/or gluonic hot spots. However, predictions of the the GW paradigm seemingly conflict with data from multiple experiments which observe coherent production of vector mesons accompanied by nuclear excitation, or in peripheral relativistic heavy-ion collisions. These data are consistent with a simpler, semi-classical approach. We will discuss this contradiction and explore how and why GW fails. We will also contrast the significant differences in incoherent photoproduction on $^{197}$Au and $^{208}$Pb targets in the GW approach with the much smaller expected differences in their low$-x$ gluon content. |
1112.4749 | Jose Rodriguez-Quintero | J. Rodr\'iguez-Quintero | The dimension-two gluon condensate, the ghost-gluon vertex and the
Taylor theorem | Oral contribution to QCDTNT-II (Trento, 2011) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the genuine non-perturbative corrections to the Landau gauge
ghost-gluon vertex in terms of the non-vanishing dimension-two gluon
condensate, and prove these corrections to give account of current SU(2)
lattice data for the vertex with different kinematical configurations in the
domain of intermediate momenta, roughly above 2-3 GeV. Based on this OPE
analysis, we also present a simple model for the vertex, in acceptable
agreement with the lattice data also in the IR domain. The necessity of a
non-vanishing dimension-two gluon condensate will be also investigated through
the analysis of the running coupling defined by the ghost-gluon vertex in
Taylor kinematics.
| [
{
"created": "Tue, 20 Dec 2011 16:06:54 GMT",
"version": "v1"
}
] | 2011-12-21 | [
[
"Rodríguez-Quintero",
"J.",
""
]
] | We study the genuine non-perturbative corrections to the Landau gauge ghost-gluon vertex in terms of the non-vanishing dimension-two gluon condensate, and prove these corrections to give account of current SU(2) lattice data for the vertex with different kinematical configurations in the domain of intermediate momenta, roughly above 2-3 GeV. Based on this OPE analysis, we also present a simple model for the vertex, in acceptable agreement with the lattice data also in the IR domain. The necessity of a non-vanishing dimension-two gluon condensate will be also investigated through the analysis of the running coupling defined by the ghost-gluon vertex in Taylor kinematics. |
1611.05048 | Nicholas Orlofsky | John Kearney, Nicholas Orlofsky, Aaron Pierce | $Z$ boson mediated dark matter beyond the effective theory | 10 pages, 3 figures; v2: published version | Phys. Rev. D 95, 035020 (2017) | 10.1103/PhysRevD.95.035020 | FERMILAB-PUB-16-534-T, MCTP-16-27 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Direct detection bounds are beginning to constrain a very simple model of
weakly interacting dark matter---a Majorana fermion with a coupling to the $Z$
boson. In a particularly straightforward gauge-invariant realization, this
coupling is introduced via a higher-dimensional operator. While attractive in
its simplicity, this model generically induces a large $\rho$ parameter. An
ultraviolet completion that avoids an overly large contribution to $\rho$ is
the singlet-doublet model. We revisit this model, focusing on the Higgs blind
spot region of parameter space where spin-independent interactions are absent.
This model successfully reproduces dark matter with direct detection mediated
by the $Z$ boson, but whose cosmology may depend on additional couplings and
states. Future direct detection experiments should effectively probe a
significant portion of this parameter space, aside from a small coannihilating
region. As such, $Z$-mediated thermal dark matter as realized in the
singlet-doublet model represents an interesting target for future searches.
| [
{
"created": "Tue, 15 Nov 2016 21:00:08 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Apr 2017 16:38:20 GMT",
"version": "v2"
}
] | 2017-04-11 | [
[
"Kearney",
"John",
""
],
[
"Orlofsky",
"Nicholas",
""
],
[
"Pierce",
"Aaron",
""
]
] | Direct detection bounds are beginning to constrain a very simple model of weakly interacting dark matter---a Majorana fermion with a coupling to the $Z$ boson. In a particularly straightforward gauge-invariant realization, this coupling is introduced via a higher-dimensional operator. While attractive in its simplicity, this model generically induces a large $\rho$ parameter. An ultraviolet completion that avoids an overly large contribution to $\rho$ is the singlet-doublet model. We revisit this model, focusing on the Higgs blind spot region of parameter space where spin-independent interactions are absent. This model successfully reproduces dark matter with direct detection mediated by the $Z$ boson, but whose cosmology may depend on additional couplings and states. Future direct detection experiments should effectively probe a significant portion of this parameter space, aside from a small coannihilating region. As such, $Z$-mediated thermal dark matter as realized in the singlet-doublet model represents an interesting target for future searches. |
2105.02840 | Alessandro Strumia | Christian Gross, Giacomo Landini, Alessandro Strumia, Daniele Teresi | Dark Matter as dark dwarfs and other macroscopic objects: multiverse
relics? | 24 pages, 4 figures. Final published version. Webinar presentation of
the paper https://www.youtube.com/watch?v=y5WONNDJbWc | J.HEP 09 (2021) 33 | null | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | First-order phase transitions can leave relic pockets of false vacua and
their particles, that manifest as macroscopic Dark Matter. We compute one
predictive model: a gauge theory with a dark quark relic heavier than the
confinement scale. During the first-order phase transition to confinement, dark
quarks remain in the false vacuum and get compressed, forming Fermi balls that
can undergo gravitational collapse to stable dark dwarfs (bound states
analogous to white dwarfs) near the Chandrasekhar limit, or to primordial black
holes.
| [
{
"created": "Thu, 6 May 2021 17:32:48 GMT",
"version": "v1"
},
{
"created": "Sun, 3 Apr 2022 18:22:09 GMT",
"version": "v2"
}
] | 2022-04-05 | [
[
"Gross",
"Christian",
""
],
[
"Landini",
"Giacomo",
""
],
[
"Strumia",
"Alessandro",
""
],
[
"Teresi",
"Daniele",
""
]
] | First-order phase transitions can leave relic pockets of false vacua and their particles, that manifest as macroscopic Dark Matter. We compute one predictive model: a gauge theory with a dark quark relic heavier than the confinement scale. During the first-order phase transition to confinement, dark quarks remain in the false vacuum and get compressed, forming Fermi balls that can undergo gravitational collapse to stable dark dwarfs (bound states analogous to white dwarfs) near the Chandrasekhar limit, or to primordial black holes. |
0710.2322 | Alexey Gladyshev | A.V. Gladyshev, D.I. Kazakov, M.G. Paucar (JINR, Dubna) | Long-living superpartners in the MSSM | Submitted for the SUSY07 proceedings | null | null | null | hep-ph | null | The parameter space of the Constrained Minimal supersymmetric Standard Model
is considered. It is shown that for the particular choice of parameters there
are some regions where long-living charged superparticles exist. Two regions of
interest are the co-annihilation region with light staus, and the region with
large negative trilinear scalar coupling A distinguished by light stops. The
phenomenology of long-living superparticles is briefly discussed.
| [
{
"created": "Thu, 11 Oct 2007 19:16:37 GMT",
"version": "v1"
}
] | 2007-10-12 | [
[
"Gladyshev",
"A. V.",
"",
"JINR, Dubna"
],
[
"Kazakov",
"D. I.",
"",
"JINR, Dubna"
],
[
"Paucar",
"M. G.",
"",
"JINR, Dubna"
]
] | The parameter space of the Constrained Minimal supersymmetric Standard Model is considered. It is shown that for the particular choice of parameters there are some regions where long-living charged superparticles exist. Two regions of interest are the co-annihilation region with light staus, and the region with large negative trilinear scalar coupling A distinguished by light stops. The phenomenology of long-living superparticles is briefly discussed. |
hep-ph/9204239 | Charles Gale | K. Haglin, C. Gale and V. Emel'yanov | Virtual bremsstrahlung from pions and quarks in thermalized hadronic
matter | 9 pages | Phys.Rev.D46:4082-4086,1992 | 10.1103/PhysRevD.46.4082 | null | hep-ph | null | A soft photon approximation is used to calculate the rates of lepton pair
production through virtual bremsstrahlung from both pions and quarks. Standard
assumptions about the evolution of a nuclear system under collision allow pion
and quark driven total production to be calculated. Comparisons are made with
Dalitz decay of light mesons. These mechanisms are expected to be significant
contributors to the soft dilepton mass spectra one might observe in heavy ion
collisions at RHIC and LHC energies.
| [
{
"created": "Thu, 30 Apr 1992 18:12:56 GMT",
"version": "v1"
}
] | 2010-01-15 | [
[
"Haglin",
"K.",
""
],
[
"Gale",
"C.",
""
],
[
"Emel'yanov",
"V.",
""
]
] | A soft photon approximation is used to calculate the rates of lepton pair production through virtual bremsstrahlung from both pions and quarks. Standard assumptions about the evolution of a nuclear system under collision allow pion and quark driven total production to be calculated. Comparisons are made with Dalitz decay of light mesons. These mechanisms are expected to be significant contributors to the soft dilepton mass spectra one might observe in heavy ion collisions at RHIC and LHC energies. |
hep-ph/9903527 | Nils Hammon | N. Hammon, H. St\"ocker, W. Greiner | Non-equilibrium initial conditions from pQCD for RHIC and LHC | typo in ref's removed, ack's added, no change in results | Phys.Rev.C61:014901,2000 | 10.1103/PhysRevC.61.014901 | null | hep-ph | null | We calculate the initial non-equilibrium conditions from perturbative QCD
(pQCD) within Glauber multiple scattering theory for $\sqrt s =200$ AGeV and
$\sqrt s =5.5$ ATeV. At the soon available collider energies one will
particularly test the small $x$ region of the parton distributions entering the
cross sections. Therefore shadowing effects, previously more or less
unimportant, will lead to new effects on variables such as particle
multiplicities $dN/dy$, transverse energy production $d\bar{E}_T/dy$, and the
initial temperature $T_i$. In this paper we will have a closer look on the
effects of shadowing by employing different parametrizations for the shadowing
effect for valence quarks, sea quarks and gluons. Since the cross sections at
midrapidity are dominated by processes involving gluons the amount of their
depletion is particularly important. We will therefore have a closer look on
the results for $dN/dy$, $d\bar{E}_T/dy$, and $T_i$ by using two different
gluon shadowing ratios, differing strongly in size. As a matter of fact, the
calculated quantities differ significantly.
| [
{
"created": "Tue, 30 Mar 1999 10:40:22 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Apr 1999 09:11:04 GMT",
"version": "v2"
},
{
"created": "Tue, 20 Apr 1999 09:01:53 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Hammon",
"N.",
""
],
[
"Stöcker",
"H.",
""
],
[
"Greiner",
"W.",
""
]
] | We calculate the initial non-equilibrium conditions from perturbative QCD (pQCD) within Glauber multiple scattering theory for $\sqrt s =200$ AGeV and $\sqrt s =5.5$ ATeV. At the soon available collider energies one will particularly test the small $x$ region of the parton distributions entering the cross sections. Therefore shadowing effects, previously more or less unimportant, will lead to new effects on variables such as particle multiplicities $dN/dy$, transverse energy production $d\bar{E}_T/dy$, and the initial temperature $T_i$. In this paper we will have a closer look on the effects of shadowing by employing different parametrizations for the shadowing effect for valence quarks, sea quarks and gluons. Since the cross sections at midrapidity are dominated by processes involving gluons the amount of their depletion is particularly important. We will therefore have a closer look on the results for $dN/dy$, $d\bar{E}_T/dy$, and $T_i$ by using two different gluon shadowing ratios, differing strongly in size. As a matter of fact, the calculated quantities differ significantly. |
2004.01706 | Brian Coffey Dr | Bryan W. Lynn, Brian J. Coffey, Kellen E. McGee, and Glenn D. Starkman | Nuclear matter as a liquid phase of spontaneously broken semi-classical
$SU(2)_L \times SU(2)_R$ chiral perturbation theory: Static chiral nucleon
liquids | 68 pages, 4 figures, subbmitted to Phys. Rev. C. arXiv admin note:
substantial text overlap with arXiv:1811.10784 | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study effective field theories (EFT) of nuclear structure based on
spontaneously broken global $SU(2)_L\times SU(2)_R$ chiral symmetry of QCD with
two massless quarks, i.e. $SU(2)\chi PT$. For ground-state nuclei, this EFT
enables expansion and truncation in inverse powers of $\Lambda_{\chi SB}\simeq
1 GeV$, with analytic operators renormalized to all loop orders. We derive the
EFT Lagrangian to order $\Lambda^0_{\chi SB}$.
We show that $SU(2)\chi PT$ of protons, neutrons and pions admits a
semi-classical "Static Chiral Nucleon Liquid" (Static$\chi$NL) phase and that
"Pion-less" $SU(2)\chi PT$ emerges in this liquid: far-infrared pions decouple
from Static$\chi$NL, vastly simplifying the derivation of saturated nuclear
matter (the infinite liquid phase) and of finite microscopic liquid drops
(ground-state nuclides).
Static$\chi$NL are made entirely of nucleons with even parity, total spin
zero, and even $Z$ and $N$; local expectation values for spin and momenta
vanish. They explain the power of pion-less $SU(2)\chi PT$ to capture
experimental ground-state properties of certain nuclides, this explanation
following directly from the global symmetries of QCD with two massless quarks.
Mean-field Static$\chi$NL non-topological solitons are true solutions of
$SU(2)\chi PT$'s semi-classical symmetries: they obey all CVC and PCAC
conservation laws and they have zero internal and external pressure. The
nuclear liquid-drop model and the semi-empirical mass formula emerge -- with
correct nuclear density and saturation and asymmetry energies -- in an explicit
Thomas-Fermi construction.
We relate our work to compatible and complementary work in pionless and in
halo/ cluster EFTs, also composed entirely of nucleons and applied to light
($A\leq 6$) nuclei, which might provide important (<12.5%) corrections to
Static$\chi NL$.
| [
{
"created": "Fri, 3 Apr 2020 08:08:31 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Dec 2021 17:56:43 GMT",
"version": "v2"
}
] | 2021-12-17 | [
[
"Lynn",
"Bryan W.",
""
],
[
"Coffey",
"Brian J.",
""
],
[
"McGee",
"Kellen E.",
""
],
[
"Starkman",
"Glenn D.",
""
]
] | We study effective field theories (EFT) of nuclear structure based on spontaneously broken global $SU(2)_L\times SU(2)_R$ chiral symmetry of QCD with two massless quarks, i.e. $SU(2)\chi PT$. For ground-state nuclei, this EFT enables expansion and truncation in inverse powers of $\Lambda_{\chi SB}\simeq 1 GeV$, with analytic operators renormalized to all loop orders. We derive the EFT Lagrangian to order $\Lambda^0_{\chi SB}$. We show that $SU(2)\chi PT$ of protons, neutrons and pions admits a semi-classical "Static Chiral Nucleon Liquid" (Static$\chi$NL) phase and that "Pion-less" $SU(2)\chi PT$ emerges in this liquid: far-infrared pions decouple from Static$\chi$NL, vastly simplifying the derivation of saturated nuclear matter (the infinite liquid phase) and of finite microscopic liquid drops (ground-state nuclides). Static$\chi$NL are made entirely of nucleons with even parity, total spin zero, and even $Z$ and $N$; local expectation values for spin and momenta vanish. They explain the power of pion-less $SU(2)\chi PT$ to capture experimental ground-state properties of certain nuclides, this explanation following directly from the global symmetries of QCD with two massless quarks. Mean-field Static$\chi$NL non-topological solitons are true solutions of $SU(2)\chi PT$'s semi-classical symmetries: they obey all CVC and PCAC conservation laws and they have zero internal and external pressure. The nuclear liquid-drop model and the semi-empirical mass formula emerge -- with correct nuclear density and saturation and asymmetry energies -- in an explicit Thomas-Fermi construction. We relate our work to compatible and complementary work in pionless and in halo/ cluster EFTs, also composed entirely of nucleons and applied to light ($A\leq 6$) nuclei, which might provide important (<12.5%) corrections to Static$\chi NL$. |
hep-ph/0105042 | David Berenstein | David Berenstein, Vishnu Jejjala, Robert G. Leigh | The Standard Model on a D-brane | 8 pages Latex, 1 fig. v2: discussion improved, added new references | Phys.Rev.Lett. 88 (2002) 071602 | 10.1103/PhysRevLett.88.071602 | ILL-(TH)-01-02 | hep-ph hep-th | null | We present a consistent string theory model which reproduces the Standard
Model, consisting of a D3-brane at a simple orbifold singularity. We study some
simple features of the phenomenology of the model. We find that the scale of
stringy physics must be in the multi-TeV range. There are natural hierarchies
in the fermion spectrum and there are several possible experimental signatures
of the model.
| [
{
"created": "Fri, 4 May 2001 20:07:23 GMT",
"version": "v1"
},
{
"created": "Wed, 9 May 2001 17:14:37 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Berenstein",
"David",
""
],
[
"Jejjala",
"Vishnu",
""
],
[
"Leigh",
"Robert G.",
""
]
] | We present a consistent string theory model which reproduces the Standard Model, consisting of a D3-brane at a simple orbifold singularity. We study some simple features of the phenomenology of the model. We find that the scale of stringy physics must be in the multi-TeV range. There are natural hierarchies in the fermion spectrum and there are several possible experimental signatures of the model. |
1312.5278 | Pierre Grange | Pierre Grange' (LUPM), Jean-Francois Mathiot (LPC-CLERMONT), Bruno
Mutet (LPC-CLERMONT), Ernst Werner | Aspects of fine-tuning of the Higgs mass within finite field theories | 9 pages. arXiv admin note: substantial text overlap with
arXiv:1011.1740 | Physical Review D 88, 12 (2013) 125015 | 10.1103/PhysRevD.88.125015 | null | hep-ph hep-th math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We reanalyze the perturbative radiative corrections to the Higgs mass within
the Standard Model in the light of the Taylor-Lagrange renormalization scheme.
This scheme naturally leads to completely finite corrections, depending on an
arbitrary scale. The formulation avoids very large individual corrections to
the Higgs mass. This illustrates the fact that the so-called fine-tuning
problem in the Standard Model is just an artifact of the regularization scheme.
It should therefore not lead to any physical interpretation in terms of the
energy scale at which new physics should show up, nor in terms of a new
symmetry. We analyze the intrinsic physical scales relevant for the description
of these radiative corrections.
| [
{
"created": "Wed, 18 Dec 2013 19:26:54 GMT",
"version": "v1"
}
] | 2013-12-19 | [
[
"Grange'",
"Pierre",
"",
"LUPM"
],
[
"Mathiot",
"Jean-Francois",
"",
"LPC-CLERMONT"
],
[
"Mutet",
"Bruno",
"",
"LPC-CLERMONT"
],
[
"Werner",
"Ernst",
""
]
] | We reanalyze the perturbative radiative corrections to the Higgs mass within the Standard Model in the light of the Taylor-Lagrange renormalization scheme. This scheme naturally leads to completely finite corrections, depending on an arbitrary scale. The formulation avoids very large individual corrections to the Higgs mass. This illustrates the fact that the so-called fine-tuning problem in the Standard Model is just an artifact of the regularization scheme. It should therefore not lead to any physical interpretation in terms of the energy scale at which new physics should show up, nor in terms of a new symmetry. We analyze the intrinsic physical scales relevant for the description of these radiative corrections. |
1606.04054 | Hong-Jian He | Hong-Jian He, Xun-Jie Xu | Connecting Leptonic Unitarity Triangle to Neutrino Oscillation with CP
Violation in Vacuum and in Matter | PRD Final Version (9pp, 5 Figs). All results/conclusions un-changed.
Further added new Fig.5 for analysis of LBL experiment DUNE. Only minor
rewording to clarify the Importance of this work | Phys. Rev. D 95, 033002 (2017) | 10.1103/PhysRevD.95.033002 | null | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Leptonic unitarity triangle (LUT) provides fundamental means to geometrically
describe CP violation in neutrino oscillation. In this work, we use LUT to
present a new geometrical interpretation of the vacuum oscillation probability,
and derive a compact new oscillation formula in terms of only 3 independent
parameters of the corresponding LUT. Then, we systematically study matter
effects in the geometrical formulation of neutrino oscillation with CP
violation. Including nontrivial matter effects, we derive a very compact new
oscillation formula by using the LUT formulation. We further demonstrate that
this geometrical formula holds well for applications to neutrino oscillations
in matter, including the long baseline experiments T2K, MINOS, NOvA, and DUNE.
| [
{
"created": "Mon, 13 Jun 2016 18:16:47 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Jun 2016 19:23:59 GMT",
"version": "v2"
},
{
"created": "Tue, 13 Dec 2016 16:54:05 GMT",
"version": "v3"
}
] | 2017-02-22 | [
[
"He",
"Hong-Jian",
""
],
[
"Xu",
"Xun-Jie",
""
]
] | Leptonic unitarity triangle (LUT) provides fundamental means to geometrically describe CP violation in neutrino oscillation. In this work, we use LUT to present a new geometrical interpretation of the vacuum oscillation probability, and derive a compact new oscillation formula in terms of only 3 independent parameters of the corresponding LUT. Then, we systematically study matter effects in the geometrical formulation of neutrino oscillation with CP violation. Including nontrivial matter effects, we derive a very compact new oscillation formula by using the LUT formulation. We further demonstrate that this geometrical formula holds well for applications to neutrino oscillations in matter, including the long baseline experiments T2K, MINOS, NOvA, and DUNE. |
2108.04246 | Wen Yin | Wen Yin | Small cosmological constant from a peculiar inflaton potential | 21pages, 3figures; | null | 10.1103/PhysRevD.106.055014 | null | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a novel scenario to explain the small cosmological constant (CC)
by a finely tuned inflaton potential. The tuned shape is stable under radiative
corrections, and our setup is technically natural. The peculiar po- tential
approximately satisfies the following conditions: the inflation is eternal if
CC is positive, and not eternal if CC is negative. By introducing a slowly
varying CC from a positive value to a negative value, the dominant volume of
the Universe after the inflation turns out to have a vanishingly small CC. The
scenario does not require eternal inflation but the e-folding number is
exponentially large and the inflation scale should be low enough. The scenario
can have a consistent thermal history, but the present equation of state of the
Universe is predicted to differ from the prediction of the {\Lambda}CDM model.
A concrete model with a light scalar field is studied.
| [
{
"created": "Mon, 9 Aug 2021 18:00:00 GMT",
"version": "v1"
}
] | 2022-10-05 | [
[
"Yin",
"Wen",
""
]
] | We propose a novel scenario to explain the small cosmological constant (CC) by a finely tuned inflaton potential. The tuned shape is stable under radiative corrections, and our setup is technically natural. The peculiar po- tential approximately satisfies the following conditions: the inflation is eternal if CC is positive, and not eternal if CC is negative. By introducing a slowly varying CC from a positive value to a negative value, the dominant volume of the Universe after the inflation turns out to have a vanishingly small CC. The scenario does not require eternal inflation but the e-folding number is exponentially large and the inflation scale should be low enough. The scenario can have a consistent thermal history, but the present equation of state of the Universe is predicted to differ from the prediction of the {\Lambda}CDM model. A concrete model with a light scalar field is studied. |
hep-ph/0301037 | Alon Faraggi | Gerald B. Cleaver, Alon E. Faraggi and Sander Nooij | NAHE-based string models with SU(4) X SU(2) X U(1) SO(10) Subgroup | 25 pages. Standard Latex. Revised version to appear in NPB | Nucl.Phys. B672 (2003) 64-86 | 10.1016/j.nuclphysb.2003.09.012 | BU-HEPP-02/13, CASPER-02/05, OUTP-03-01P | hep-ph hep-th | null | The orbifold GUT doublet-triplet splitting mechanism was discussed in 1994 in
the framework of the NAHE-based free fermionic models in which the SO(10) GUT
symmetry is broken to SO(6) X SO(4), SU(3) X SU(2) X U(1)^2, or SU(3) X U(1) X
SU(2)^2. In this paper we study NAHE-based free fermionic models in which the
SO(10) symmetry is broken at the string level to SU(4) X SU(2) X U(1). In
addition to the doublet-triplet splitting this case also has the advantage of
inducing the doublet-doublet splitting already at the string level. We
demonstrate, however, that NAHE-based models with SU(4) X SU(2) X U(1) SO(10)
subgroup are not viable. We show that, similarly to the LRS models, and in
contrast to the FSU5, PS and SLM models, the SU421 case gives rise to models
without an anomalous U(1) symmetry, and discuss the different cases in terms of
their N=4 origins.
| [
{
"created": "Tue, 7 Jan 2003 11:18:48 GMT",
"version": "v1"
},
{
"created": "Thu, 4 Sep 2003 15:04:58 GMT",
"version": "v2"
}
] | 2015-06-25 | [
[
"Cleaver",
"Gerald B.",
""
],
[
"Faraggi",
"Alon E.",
""
],
[
"Nooij",
"Sander",
""
]
] | The orbifold GUT doublet-triplet splitting mechanism was discussed in 1994 in the framework of the NAHE-based free fermionic models in which the SO(10) GUT symmetry is broken to SO(6) X SO(4), SU(3) X SU(2) X U(1)^2, or SU(3) X U(1) X SU(2)^2. In this paper we study NAHE-based free fermionic models in which the SO(10) symmetry is broken at the string level to SU(4) X SU(2) X U(1). In addition to the doublet-triplet splitting this case also has the advantage of inducing the doublet-doublet splitting already at the string level. We demonstrate, however, that NAHE-based models with SU(4) X SU(2) X U(1) SO(10) subgroup are not viable. We show that, similarly to the LRS models, and in contrast to the FSU5, PS and SLM models, the SU421 case gives rise to models without an anomalous U(1) symmetry, and discuss the different cases in terms of their N=4 origins. |
hep-ph/0303122 | Xuelei Wang | Gongru Lu, Furong Yin, Xuelei Wang, Lingde Wan | The rare top quark decays $t\to cV$ in the topcolor-assisted technicolor
model | 14 pages, 4 figures | Phys.Rev. D68 (2003) 015002 | 10.1103/PhysRevD.68.015002 | null | hep-ph | null | We consider the rare top quark decays in the framework of topcolor-assisted
technicolor (TC2) model. We find that the contributions of top-pions and
top-Higgs predicted by the TC2 model can enhance the SM branching ratios by as
much as 6-9 orders of magnitude. i.e., in the most case, the orders of
magnitude of branching ratios are $Br(t\to c g)\sim 10^{-5}$, $Br(t\to c Z)\sim
10^{-5}$, $Br(t\to c \gamma)\sim 10^{-7}$. With the reasonable values of the
parameters in TC2 model, such rare top quark decays may be testable in the
future experiments. So, rare top quark decays provide us a unique way to test
TC2 model.
| [
{
"created": "Fri, 14 Mar 2003 13:09:34 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Lu",
"Gongru",
""
],
[
"Yin",
"Furong",
""
],
[
"Wang",
"Xuelei",
""
],
[
"Wan",
"Lingde",
""
]
] | We consider the rare top quark decays in the framework of topcolor-assisted technicolor (TC2) model. We find that the contributions of top-pions and top-Higgs predicted by the TC2 model can enhance the SM branching ratios by as much as 6-9 orders of magnitude. i.e., in the most case, the orders of magnitude of branching ratios are $Br(t\to c g)\sim 10^{-5}$, $Br(t\to c Z)\sim 10^{-5}$, $Br(t\to c \gamma)\sim 10^{-7}$. With the reasonable values of the parameters in TC2 model, such rare top quark decays may be testable in the future experiments. So, rare top quark decays provide us a unique way to test TC2 model. |
hep-ph/0512066 | Tobias Huber | T. Huber, E. Lunghi, M. Misiak, D. Wyler | Electromagnetic Logarithms in B -> X_s l+ l- | Corrections in Eqs. (85), (89), (94), (128). Minor numerical changes
in Eqs. (10)-(13). The final central values and total errors remain
unaffected | Nucl.Phys.B740:105-137,2006 | 10.1016/j.nuclphysb.2006.01.037 | ZU-TH 06/05; IFT-6/2005; FERMILAB-PUB-05-531-T | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The B -> X_s l+ l- decay rate is known at the next-to-next-to-leading order
in QCD. It is proportional to alpha_em (mu)^2 and has a +- 4% scale uncertainty
before including the O(alpha_em log(M_W^2/m_b^2)) electromagnetic corrections.
We evaluate these corrections and confirm the earlier findings of Bobeth et al.
>. Furthermore, we complete the calculation of logarithmically enhanced
electromagnetic effects by including also QED corrections to the matrix
elements of four-fermion operators. Such corrections contain a collinear
logarithm log(m_b^2/m_l^2) that survives integration over the low dilepton
invariant mass region 1 GeV^2 < q^2 < 6 GeV^2 and enhances the integrated decay
rate in this domain. For the low-q^2 integrated branching ratio in the muonic
case, we find B (B -> X_s mu^+mu^-) = (1.59 +- 0.11) 10^(-6), where the error
includes the parametric and perturbative uncertainties only. For B (B -> X_s
e^+e^-), in the current BaBar and Belle setups, the logarithm of the lepton
mass gets replaced by angular cut parameters and the integrated branching ratio
for the electrons is expected to be close to that for the muons.
| [
{
"created": "Mon, 5 Dec 2005 18:31:05 GMT",
"version": "v1"
},
{
"created": "Thu, 26 Jan 2006 08:51:58 GMT",
"version": "v2"
},
{
"created": "Thu, 3 May 2007 13:50:18 GMT",
"version": "v3"
},
{
"created": "Wed, 12 Oct 2011 14:31:47 GMT",
"version": "v4"
}
] | 2011-10-13 | [
[
"Huber",
"T.",
""
],
[
"Lunghi",
"E.",
""
],
[
"Misiak",
"M.",
""
],
[
"Wyler",
"D.",
""
]
] | The B -> X_s l+ l- decay rate is known at the next-to-next-to-leading order in QCD. It is proportional to alpha_em (mu)^2 and has a +- 4% scale uncertainty before including the O(alpha_em log(M_W^2/m_b^2)) electromagnetic corrections. We evaluate these corrections and confirm the earlier findings of Bobeth et al. >. Furthermore, we complete the calculation of logarithmically enhanced electromagnetic effects by including also QED corrections to the matrix elements of four-fermion operators. Such corrections contain a collinear logarithm log(m_b^2/m_l^2) that survives integration over the low dilepton invariant mass region 1 GeV^2 < q^2 < 6 GeV^2 and enhances the integrated decay rate in this domain. For the low-q^2 integrated branching ratio in the muonic case, we find B (B -> X_s mu^+mu^-) = (1.59 +- 0.11) 10^(-6), where the error includes the parametric and perturbative uncertainties only. For B (B -> X_s e^+e^-), in the current BaBar and Belle setups, the logarithm of the lepton mass gets replaced by angular cut parameters and the integrated branching ratio for the electrons is expected to be close to that for the muons. |
1412.1541 | Soo-hyeon Nam | Kang Young Lee and Soo-hyeon Nam | LHC Phenomenology of Z' and Z" bosons in the SU(4)_L \times U(1)_X
little Higgs model | 9 pages, 11 figures, references added, typos corrected | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine direct limits on masses of the extra neutral gauge bosons in the
SU(4)_L \times U(1)_X model with a little Higgs mechanism confronted with the
LHC data, especially by embedding anomaly-free set of fermions. There exist two
extra neutral gauge bosons, calling Z' and Z", in this model. The lower
exclusion limit of the mass of the lighter extra neutral gauge boson is about 3
TeV while that of the heavier one 5 TeV. For comparison, we examine the mass
limit of Z'_3 boson in the SU(3)_L \times U(1)_X model as well, and discuss the
implication of our result in the SU(4)_L \times U(1)_X model with a standard
Higgs mechanism. We also discuss the discovery potential of Z' and Z" at the
future LHC with the center-of-momentum energy of 14 TeV. Our results can be
applicable to the models with regular Higgs mechanism if the same type of
fermion family is assigned.
| [
{
"created": "Thu, 4 Dec 2014 02:12:42 GMT",
"version": "v1"
},
{
"created": "Sun, 16 Aug 2015 13:42:48 GMT",
"version": "v2"
}
] | 2015-08-18 | [
[
"Lee",
"Kang Young",
""
],
[
"Nam",
"Soo-hyeon",
""
]
] | We examine direct limits on masses of the extra neutral gauge bosons in the SU(4)_L \times U(1)_X model with a little Higgs mechanism confronted with the LHC data, especially by embedding anomaly-free set of fermions. There exist two extra neutral gauge bosons, calling Z' and Z", in this model. The lower exclusion limit of the mass of the lighter extra neutral gauge boson is about 3 TeV while that of the heavier one 5 TeV. For comparison, we examine the mass limit of Z'_3 boson in the SU(3)_L \times U(1)_X model as well, and discuss the implication of our result in the SU(4)_L \times U(1)_X model with a standard Higgs mechanism. We also discuss the discovery potential of Z' and Z" at the future LHC with the center-of-momentum energy of 14 TeV. Our results can be applicable to the models with regular Higgs mechanism if the same type of fermion family is assigned. |
hep-ph/0301200 | Nestor Armesto Perez | N. Armesto and C. A. Salgado | Gluon distributions in nuclei at small x: guidance from different models | 6 pages, LaTeX2e, uses enclosed cernrep.cls, one eps figure enclosed
using graphicx, contribution to the Yellow Report on Hard Probes in Heavy Ion
Collisions at the LHC | null | null | UCOFIS 1/03 | hep-ph | null | Different approaches to gluon shadowing at small x are reviewed. Some
available results relevant for RHIC and LHC are compared.
| [
{
"created": "Thu, 23 Jan 2003 11:16:57 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Armesto",
"N.",
""
],
[
"Salgado",
"C. A.",
""
]
] | Different approaches to gluon shadowing at small x are reviewed. Some available results relevant for RHIC and LHC are compared. |
hep-ph/9605239 | Oreste Nicrosini | A. Arbuzov, M. Bigi, H. Burkhardt, M. Cacciari, M. Caffo, H. Czy\.z,
M. Dallavalle, J.H. Field, F. Filthaut, S. Jadach, F. Jegerlehner, E. Kuraev,
G. Montagna, O. Nicrosini, F. Piccinini, B. Pietrzyk, W. P{\l}aczek, E.
Remiddi, M. Skrzypek, L. Trentadue, B.F.L. Ward, Z. W\c{a}s | The present theoretical error on the Bhabha scattering cross section in
the luminometry region at LEP | 7 pages | Phys.Lett. B383 (1996) 238-242 | 10.1016/0370-2693(96)00733-2 | null | hep-ph | null | The results concerning the theoretical evaluation of the small-angle Bhabha
Scattering cross section obtained during the Workshop on Physics at LEP2 (CERN,
Geneva, Switzerland, 1995) by the Working Group ``Event Generators for Bhabha
Scattering'' are summarized. The estimate of the theoretical error on the cross
section in the luminometry region is updated.
| [
{
"created": "Tue, 7 May 1996 08:25:51 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Arbuzov",
"A.",
""
],
[
"Bigi",
"M.",
""
],
[
"Burkhardt",
"H.",
""
],
[
"Cacciari",
"M.",
""
],
[
"Caffo",
"M.",
""
],
[
"Czyż",
"H.",
""
],
[
"Dallavalle",
"M.",
""
],
[
"Field",
"J. H.",
... | The results concerning the theoretical evaluation of the small-angle Bhabha Scattering cross section obtained during the Workshop on Physics at LEP2 (CERN, Geneva, Switzerland, 1995) by the Working Group ``Event Generators for Bhabha Scattering'' are summarized. The estimate of the theoretical error on the cross section in the luminometry region is updated. |
hep-ph/9907327 | Fred Jegerlehner | J. Fleischer, F. Jegerlehner and O.V. Tarasov | Algebraic reduction of one-loop Feynman graph amplitudes | 18 pages, 1 figure, added references, expanded introduction, improved
text | Nucl.Phys.B566:423-440,2000 | 10.1016/S0550-3213(99)00678-1 | DESY 99-086 | hep-ph | null | An algorithm for the reduction of one-loop n-point tensor integrals to basic
integrals is proposed. We transform tensor integrals to scalar integrals with
shifted dimension and reduce these by recurrence relations to integrals in
generic dimension. Also the integration-by-parts method is used to reduce
indices (powers of scalar propagators) of the scalar diagrams. The obtained
recurrence relations for one-loop integrals are explicitly evaluated for 5- and
6-point functions. In the latter case the corresponding Gram determinant
vanishes identically for d=4, which greatly simplifies the application of the
recurrence relations.
| [
{
"created": "Tue, 13 Jul 1999 08:13:32 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Oct 1999 15:43:13 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Fleischer",
"J.",
""
],
[
"Jegerlehner",
"F.",
""
],
[
"Tarasov",
"O. V.",
""
]
] | An algorithm for the reduction of one-loop n-point tensor integrals to basic integrals is proposed. We transform tensor integrals to scalar integrals with shifted dimension and reduce these by recurrence relations to integrals in generic dimension. Also the integration-by-parts method is used to reduce indices (powers of scalar propagators) of the scalar diagrams. The obtained recurrence relations for one-loop integrals are explicitly evaluated for 5- and 6-point functions. In the latter case the corresponding Gram determinant vanishes identically for d=4, which greatly simplifies the application of the recurrence relations. |
hep-ph/0409063 | Georg Weiglein | S. Heinemeyer, S. Kraml, W. Porod and G. Weiglein | Impact of a precise top mass measurement | 4 pages, 2 figures, to appear in the proceedings of LCWS04, Paris,
April 2004 | null | null | CERN-PH-TH/2004-161, DCPT/04/106, IPPP/04/53 | hep-ph | null | The physics impact of a precise determination of the top-quark mass, m_t, at
the Linear Collider (LC) is discussed, and the results are compared with the
prospective accuracy at the LHC. The importance of a precise knowledge of m_t
for electroweak precision observables and for Higgs physics in the MSSM is
pointed out in particular. We find that going from hadron collider to LC
accuracy in m_t leads to an improvement of the investigated quantities by up to
an order of magnitude.
| [
{
"created": "Mon, 6 Sep 2004 17:57:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Heinemeyer",
"S.",
""
],
[
"Kraml",
"S.",
""
],
[
"Porod",
"W.",
""
],
[
"Weiglein",
"G.",
""
]
] | The physics impact of a precise determination of the top-quark mass, m_t, at the Linear Collider (LC) is discussed, and the results are compared with the prospective accuracy at the LHC. The importance of a precise knowledge of m_t for electroweak precision observables and for Higgs physics in the MSSM is pointed out in particular. We find that going from hadron collider to LC accuracy in m_t leads to an improvement of the investigated quantities by up to an order of magnitude. |
hep-ph/0501026 | Hee-Jung Lee | Hee-Jung Lee | Instantons and Structure of Pentaquark | 6 pages, 2 figures, Talk at XVII International Baldin Seminar on High
Energy Physics Problems, Dubna, Russia, September 27 -- October 2, 2004 | null | null | null | hep-ph | null | We are discussing the influence of the complex structure of the QCD vacuum on
the properties of the exotic multiquark states, specially the possibility for
the existence of a deeply bound pentaquark. We show that the specific
spin-flavor properties of the instanton induced interaction between the quarks
leads to the existence of light tri- and di-quark clusters inside the
pentaquark. This strong quark correlations might be behind the anomalous
properties of the pentaquark.
| [
{
"created": "Wed, 5 Jan 2005 13:40:40 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lee",
"Hee-Jung",
""
]
] | We are discussing the influence of the complex structure of the QCD vacuum on the properties of the exotic multiquark states, specially the possibility for the existence of a deeply bound pentaquark. We show that the specific spin-flavor properties of the instanton induced interaction between the quarks leads to the existence of light tri- and di-quark clusters inside the pentaquark. This strong quark correlations might be behind the anomalous properties of the pentaquark. |
2109.08887 | Zhengyu Chen | Zhengyu Chen | Kinetic theory of overpopulated gluon systems with inelastic processes | new discussion on the infinite terms; Sec.III, Subsection B deleted;
references updated. arXiv admin note: text overlap with arXiv:1703.02495 by
other authors | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, the role of inelastic processes in the formation of a transient
Bose-Einstein condensation (BEC) is investigated based on kinetic theory. We
calculate the condensation rate for an overpopulated gluon system which is
assumed to be in thermal equilibrium and with the presence of a BEC. The matrix
elements of the inelastic processes are chosen as the isotropic one and the
gluons are considered to have a finite mass. Our calculations indicate that the
inelastic processes can hinder the formation of a BEC since the negatively
infinite net condensation rate can destroy any BEC instantly.
| [
{
"created": "Sat, 18 Sep 2021 09:11:36 GMT",
"version": "v1"
},
{
"created": "Sun, 6 Feb 2022 02:33:50 GMT",
"version": "v2"
}
] | 2022-02-08 | [
[
"Chen",
"Zhengyu",
""
]
] | In this work, the role of inelastic processes in the formation of a transient Bose-Einstein condensation (BEC) is investigated based on kinetic theory. We calculate the condensation rate for an overpopulated gluon system which is assumed to be in thermal equilibrium and with the presence of a BEC. The matrix elements of the inelastic processes are chosen as the isotropic one and the gluons are considered to have a finite mass. Our calculations indicate that the inelastic processes can hinder the formation of a BEC since the negatively infinite net condensation rate can destroy any BEC instantly. |
hep-ph/0005222 | Nelson Nunes | E.J. Copeland, N.J. Nunes and F. Rosati | Quintessence models in Supergravity | 6 pages, revised version to appear in PRD | Phys.Rev. D62 (2000) 123503 | 10.1103/PhysRevD.62.123503 | SUSX-TH/00-008 | hep-ph astro-ph | null | Scalar field models of quintessence typically require that the expectation
value of the field today is of order the Planck mass, if we want them to
explain the observed acceleration of the Universe. This suggests that we should
be considering models in the context of supergravity. We discuss a particular
class of supergravity models and analyze their behavior under different choices
of the Kahler metric.
| [
{
"created": "Mon, 22 May 2000 17:10:11 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Oct 2000 16:13:00 GMT",
"version": "v2"
}
] | 2019-08-17 | [
[
"Copeland",
"E. J.",
""
],
[
"Nunes",
"N. J.",
""
],
[
"Rosati",
"F.",
""
]
] | Scalar field models of quintessence typically require that the expectation value of the field today is of order the Planck mass, if we want them to explain the observed acceleration of the Universe. This suggests that we should be considering models in the context of supergravity. We discuss a particular class of supergravity models and analyze their behavior under different choices of the Kahler metric. |
1311.0836 | Ismail Zahed | Edward Shuryak and Ismail Zahed | New Regimes of Stringy (Holographic) Pomeron and High Multiplicity pp
and pA Collisions | 29 pages, 15 figures | Phys. Rev. D 89, 094001 (2014) | 10.1103/PhysRevD.89.094001 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Holographic AdS/QCD models of the Pomeron unite a string-based description of
hadronic reactions of the pre-QCD era with the perturbative BFKL approach. The
specific version we will use due to Stoffers and Zahed, is based on a
semiclassical quantization of a "tube" (closed string exchange or open string
virtual pair production) in its Euclidean formulation using the scalar Polyakov
action. This model has a number of phenomenologically successful results. The
periodicity of a coordinate around the tube allows the introduction of a
Matsubara time and therefore an effective temperature Teff on the string. We
observe that at the LHC energies and for sufficiently small impact parameter,
Teff approaches and even exceeds the Hagedorn temperature of the QCD strings.
Based on studies of the stringy thermodynamics of pure gauge theories we
suggest that there should exist two new regimes of the Pomeron: the
"near-critical" and the "post-critical" ones. In the former one, string
excitations create a high entropy "string ball", with high energy and entropy
but small pressure/free energy. If heavy enough this ball becomes a (dual)
black hole (BH). As the intrinsic temperature of the string exceeds the
Hagedorn temperature, the ball becomes a post-critical explosive "QGP ball".
The hydrodynamical explosion resulting from this scenario was predicted by us
to have radial flow exceeding that ever seen even in heavy ion collisions,
which was recently confirmed by CMS and ALICE at LHC. We also discuss the
elastic scattering profile, finding some hints for new phases in it, as well as
two-particle correlations.
| [
{
"created": "Mon, 4 Nov 2013 20:25:22 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Jan 2014 16:04:55 GMT",
"version": "v2"
}
] | 2014-05-07 | [
[
"Shuryak",
"Edward",
""
],
[
"Zahed",
"Ismail",
""
]
] | Holographic AdS/QCD models of the Pomeron unite a string-based description of hadronic reactions of the pre-QCD era with the perturbative BFKL approach. The specific version we will use due to Stoffers and Zahed, is based on a semiclassical quantization of a "tube" (closed string exchange or open string virtual pair production) in its Euclidean formulation using the scalar Polyakov action. This model has a number of phenomenologically successful results. The periodicity of a coordinate around the tube allows the introduction of a Matsubara time and therefore an effective temperature Teff on the string. We observe that at the LHC energies and for sufficiently small impact parameter, Teff approaches and even exceeds the Hagedorn temperature of the QCD strings. Based on studies of the stringy thermodynamics of pure gauge theories we suggest that there should exist two new regimes of the Pomeron: the "near-critical" and the "post-critical" ones. In the former one, string excitations create a high entropy "string ball", with high energy and entropy but small pressure/free energy. If heavy enough this ball becomes a (dual) black hole (BH). As the intrinsic temperature of the string exceeds the Hagedorn temperature, the ball becomes a post-critical explosive "QGP ball". The hydrodynamical explosion resulting from this scenario was predicted by us to have radial flow exceeding that ever seen even in heavy ion collisions, which was recently confirmed by CMS and ALICE at LHC. We also discuss the elastic scattering profile, finding some hints for new phases in it, as well as two-particle correlations. |
1006.1197 | Johan Bijnens | Johan Bijnens and Ilaria Jemos (Lund) | Hard Pion Chiral Perturbation Theory for $B\to\pi$ and $D\to\pi$
Formfactors | 16 pages, two wrong statements about relation relativistic-heavy
meson formfactors changed and (a lot of) misprints corrected. These include
misprints in the main results | Nucl.Phys.B840:54-66,2010; Erratum-ibid.B844:182-183,2011 | 10.1016/j.nuclphysb.2010.06.021 10.1016/j.nuclphysb.2010.10.024 | LU TP 10-16 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use one-loop Heavy Meson Chiral Perturbation Theory (HMCHPT) as well as a
relativistic formulation to calculate the chiral logarithms
$m^2_\pi\log{\left(m^2_\pi/\mu^2\right)}$ contributing to the formfactors of
the semileptonic $B\rightarrow \pi$ decays at momentum transfer $q^2$ away from
$q^2_\mathrm{max}=(m_B-m_\pi)^2$. We give arguments why this chiral behavior is
reliable even in the energy regime with hard or fast pions. These results can
be used to extrapolate the formfactors calculated on the lattice to lower light
meson masses.
| [
{
"created": "Mon, 7 Jun 2010 08:05:12 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Oct 2010 11:53:25 GMT",
"version": "v2"
}
] | 2010-11-30 | [
[
"Bijnens",
"Johan",
"",
"Lund"
],
[
"Jemos",
"Ilaria",
"",
"Lund"
]
] | We use one-loop Heavy Meson Chiral Perturbation Theory (HMCHPT) as well as a relativistic formulation to calculate the chiral logarithms $m^2_\pi\log{\left(m^2_\pi/\mu^2\right)}$ contributing to the formfactors of the semileptonic $B\rightarrow \pi$ decays at momentum transfer $q^2$ away from $q^2_\mathrm{max}=(m_B-m_\pi)^2$. We give arguments why this chiral behavior is reliable even in the energy regime with hard or fast pions. These results can be used to extrapolate the formfactors calculated on the lattice to lower light meson masses. |
hep-ph/0506296 | Jose W. F. Valle | M. Malinsky, J.C.Romao, J. W. F. Valle | Novel Supersymmetric SO(10) Seesaw Mechanism | 4 pages, 3 figures, revtex4, references added, typos corrected,
sharper discussion of the RGEs given | Phys.Rev.Lett.95:161801,2005 | 10.1103/PhysRevLett.95.161801 | IFIC/05-28 | hep-ph | null | We propose a new seesaw mechanism for neutrino masses within a class of
supersymmetric SO(10) models with broken D-parity. It is shown that in such
scenarios the B-L scale can be as low as TeV without generating inconsistencies
with gauge coupling unification nor with the required magnitude of the light
neutrino masses. This leads to a possibly light new neutral gauge boson as well
as relatively light quasi-Dirac heavy leptons. These particles could be at the
TeV scale and mediate lepton flavour and CP violating processes at appreciable
levels.
| [
{
"created": "Tue, 28 Jun 2005 16:17:14 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Jul 2005 08:20:14 GMT",
"version": "v2"
},
{
"created": "Fri, 29 Jul 2005 12:01:09 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Malinsky",
"M.",
""
],
[
"Romao",
"J. C.",
""
],
[
"Valle",
"J. W. F.",
""
]
] | We propose a new seesaw mechanism for neutrino masses within a class of supersymmetric SO(10) models with broken D-parity. It is shown that in such scenarios the B-L scale can be as low as TeV without generating inconsistencies with gauge coupling unification nor with the required magnitude of the light neutrino masses. This leads to a possibly light new neutral gauge boson as well as relatively light quasi-Dirac heavy leptons. These particles could be at the TeV scale and mediate lepton flavour and CP violating processes at appreciable levels. |
0708.1784 | Rogerio Rosenfeld | O. Bertolami and R. Rosenfeld | The Higgs portal and an unified model for dark energy and dark matter | 5 pages, no figures. New references and acknowledgment added | Int.J.Mod.Phys.A23:4817-4827,2008 | 10.1142/S0217751X08042675 | null | hep-ph astro-ph | null | We examine a scenario where the Higgs boson is coupled to an additional
singlet scalar field which we identify with a quintessence field. We show that
this results in an unified picture of dark matter and dark energy, where dark
energy is the zero-mode classical field rolling the usual quintessence
potential and the dark matter candidate is the quantum excitation (particle) of
the field, which is produced in the universe due to its coupling to the Higgs
boson.
| [
{
"created": "Mon, 13 Aug 2007 22:28:53 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Aug 2007 14:43:07 GMT",
"version": "v2"
}
] | 2008-12-25 | [
[
"Bertolami",
"O.",
""
],
[
"Rosenfeld",
"R.",
""
]
] | We examine a scenario where the Higgs boson is coupled to an additional singlet scalar field which we identify with a quintessence field. We show that this results in an unified picture of dark matter and dark energy, where dark energy is the zero-mode classical field rolling the usual quintessence potential and the dark matter candidate is the quantum excitation (particle) of the field, which is produced in the universe due to its coupling to the Higgs boson. |
2107.09557 | T. Lappi | Tuomas Lappi | Ultraperipheral collisions and low-x physics | 10 pages, 5 figure, proceedings of DIS2021 | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Ultraperipheral collisions at the LHC and RHIC offer the highest currently
available energy for photon-nucleon and photon-nucleus collisions. Thus they
are a valuable tool for studying the gluonic structure of hadrons and nuclei at
small $x$. We discuss recent theoretical work towards understanding such
exclusive processes at NLO accuracy in QCD perturbation theory. These
theoretical advances are also immediately relevant for understanding the
physics of deep inelastic scattering at small $x$. We also discuss experimental
results in ultraperipheral collisions, most prominently for exclusive vector
meson production.
| [
{
"created": "Tue, 20 Jul 2021 15:19:00 GMT",
"version": "v1"
}
] | 2021-07-21 | [
[
"Lappi",
"Tuomas",
""
]
] | Ultraperipheral collisions at the LHC and RHIC offer the highest currently available energy for photon-nucleon and photon-nucleus collisions. Thus they are a valuable tool for studying the gluonic structure of hadrons and nuclei at small $x$. We discuss recent theoretical work towards understanding such exclusive processes at NLO accuracy in QCD perturbation theory. These theoretical advances are also immediately relevant for understanding the physics of deep inelastic scattering at small $x$. We also discuss experimental results in ultraperipheral collisions, most prominently for exclusive vector meson production. |
hep-ph/9707500 | Masashi Wakamatsu Ohtsubo Laboratory | Masashi Wakamatsu and Takanori Kubota (Osaka Univ.) | Chiral Symmetry and the Nucleon Structure Functions | 20pages, LaTex, 5 Postscript figures A numerical error of the
original version was corrected. The discussion on the regularization
dependence of distribution functions has been added. A comparison with the
low energy-scale parametrization of Gloeck, Reya and Vogt has been made | Phys.Rev. D57 (1998) 5755-5766 | 10.1103/PhysRevD.57.5755 | null | hep-ph | null | The isospin asymmetry of the sea quark distribution as well as the
unexpectedly small quark spin fraction of the nucleon are two outstanding
discoveries recently made in the physics of deep-inelastic structure functions.
We evaluate here the corresponding quark distribution functions within the
framework of the chiral quark soliton model, which is an effective quark model
of baryons maximally incorporating the most important feature of low energy
QCD, i.e. the chiral symmetry and its spontaneous breakdown. It is shown that
the model can explain qualitative features of the above-mentioned nucleon
structure functions within a single framework, thereby disclosing the
importance of chiral symmetry in the physics of high energy deep-inelastic
scatterings.
| [
{
"created": "Tue, 29 Jul 1997 03:37:04 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Nov 1997 07:00:10 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Wakamatsu",
"Masashi",
"",
"Osaka Univ."
],
[
"Kubota",
"Takanori",
"",
"Osaka Univ."
]
] | The isospin asymmetry of the sea quark distribution as well as the unexpectedly small quark spin fraction of the nucleon are two outstanding discoveries recently made in the physics of deep-inelastic structure functions. We evaluate here the corresponding quark distribution functions within the framework of the chiral quark soliton model, which is an effective quark model of baryons maximally incorporating the most important feature of low energy QCD, i.e. the chiral symmetry and its spontaneous breakdown. It is shown that the model can explain qualitative features of the above-mentioned nucleon structure functions within a single framework, thereby disclosing the importance of chiral symmetry in the physics of high energy deep-inelastic scatterings. |
hep-ph/9702319 | Antonio Riotto | Antonio Riotto and Goran Senjanovi\'c | Supersymmetry and Broken Symmetries at High Temperature | Four pages, LaTeX file; a couple of refs. added. Final version
accepted for publication in Phys. Rev. Lett | Phys.Rev.Lett. 79 (1997) 349-352 | 10.1103/PhysRevLett.79.349 | FERMILAB-Pub-96/020-A and IC/97/11 | hep-ph astro-ph | null | It is generally believed that internal symmetries are necessarily restored at
high temperature in supersymmetric theories. We provide simple and natural
counterexamples to this no-go theorem for systems having a net background
charge. We exemplify our findings on abelian models, for both cases of global
and local symmetries and discuss their possible implications.
| [
{
"created": "Wed, 12 Feb 1997 21:00:31 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Jun 1997 17:16:05 GMT",
"version": "v2"
},
{
"created": "Mon, 16 Jun 1997 13:21:05 GMT",
"version": "v3"
}
] | 2009-10-30 | [
[
"Riotto",
"Antonio",
""
],
[
"Senjanović",
"Goran",
""
]
] | It is generally believed that internal symmetries are necessarily restored at high temperature in supersymmetric theories. We provide simple and natural counterexamples to this no-go theorem for systems having a net background charge. We exemplify our findings on abelian models, for both cases of global and local symmetries and discuss their possible implications. |
1011.5753 | Hiroshi Okada | Yuji Kajiyama, Hiroshi Okada | T(13) Flavor Symmetry and Decaying Dark Matter | 14 pages, 2 figures, 3 tables; version accepted for publication in
Nuclear Physics B | Nucl.Phys.B848:303-313,2011 | 10.1016/j.nuclphysb.2011.02.020 | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study a new flavor symmetric model with non-Abelian discrete symmetry
T_{13}. The T_{13} group is isomorphic to Z_{13} \rtimes Z_3, and it is the
minimal group having two complex triplets as the irreducible representations.
We show that the T_{13} symmetry can derive lepton masses and mixings
consistently. Moreover, if we assume a gauge-singlet fermionic decaying dark
matter, its decay operators are also constrained by the T_{13} symmetry so that
only dimension six operators of leptonic decay are allowed. We find that the
cosmic-ray anomalies reported by PAMELA and Fermi-LAT are explained by decaying
dark matter controlled by the T_{13} flavor symmetry.
| [
{
"created": "Fri, 26 Nov 2010 10:45:30 GMT",
"version": "v1"
},
{
"created": "Sat, 12 Mar 2011 00:08:14 GMT",
"version": "v2"
}
] | 2011-08-04 | [
[
"Kajiyama",
"Yuji",
""
],
[
"Okada",
"Hiroshi",
""
]
] | We study a new flavor symmetric model with non-Abelian discrete symmetry T_{13}. The T_{13} group is isomorphic to Z_{13} \rtimes Z_3, and it is the minimal group having two complex triplets as the irreducible representations. We show that the T_{13} symmetry can derive lepton masses and mixings consistently. Moreover, if we assume a gauge-singlet fermionic decaying dark matter, its decay operators are also constrained by the T_{13} symmetry so that only dimension six operators of leptonic decay are allowed. We find that the cosmic-ray anomalies reported by PAMELA and Fermi-LAT are explained by decaying dark matter controlled by the T_{13} flavor symmetry. |
2011.10362 | Ant\'onio Torres Manso | Mar Bastero-Gil and Ant\'onio Torres Manso | Supersymmetric $\nu$-Inflaton Dark Matter | null | null | 10.1088/1475-7516/2021/04/037 | null | hep-ph astro-ph.CO gr-qc hep-th | http://creativecommons.org/licenses/by/4.0/ | We present the supersymmetric extension of the unified model for inflation
and Dark Matter studied in Ref. arXiv:1811.02302. The scenario is based on the
incomplete decay of the inflaton field into right-handed (s)neutrino pairs. By
imposing a discrete interchange symmetry on the inflaton and the right-handed
(s)neutrinos, one can ensure the stability of the inflaton field at the global
minimum today, while still allowing it to partially decay and reheat the
Universe after inflation. Compatibility of inflationary predictions, BBN bounds
and obtaining the right DM abundance for the inflaton Dark Matter candidate
typically requires large values of its coupling to the neutrino sector, and we
use supersymmetry to protect the inflaton from potentially dangerous large
radiative corrections which may spoil the required flatness of its potential.
In addition, the inflaton will decay now predominatly into sneutrinos during
reheating, which in turn give rise both to the thermal bath made of Standard
Model particles, and inflaton particles. We have performed a through analyses
of the reheating process following the evolution of all the partners involved,
identifying the different regimes in the parameter space for the final Dark
Matter candidate. This as usual can be a WIMP-like inflaton particle or an
oscillating condensate, but we find a novel regime for a FIMP-like candidate.
| [
{
"created": "Fri, 20 Nov 2020 12:05:48 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Feb 2021 10:09:57 GMT",
"version": "v2"
}
] | 2021-04-21 | [
[
"Bastero-Gil",
"Mar",
""
],
[
"Manso",
"António Torres",
""
]
] | We present the supersymmetric extension of the unified model for inflation and Dark Matter studied in Ref. arXiv:1811.02302. The scenario is based on the incomplete decay of the inflaton field into right-handed (s)neutrino pairs. By imposing a discrete interchange symmetry on the inflaton and the right-handed (s)neutrinos, one can ensure the stability of the inflaton field at the global minimum today, while still allowing it to partially decay and reheat the Universe after inflation. Compatibility of inflationary predictions, BBN bounds and obtaining the right DM abundance for the inflaton Dark Matter candidate typically requires large values of its coupling to the neutrino sector, and we use supersymmetry to protect the inflaton from potentially dangerous large radiative corrections which may spoil the required flatness of its potential. In addition, the inflaton will decay now predominatly into sneutrinos during reheating, which in turn give rise both to the thermal bath made of Standard Model particles, and inflaton particles. We have performed a through analyses of the reheating process following the evolution of all the partners involved, identifying the different regimes in the parameter space for the final Dark Matter candidate. This as usual can be a WIMP-like inflaton particle or an oscillating condensate, but we find a novel regime for a FIMP-like candidate. |
hep-ph/0202221 | Egle Tomasi-Gustafsson | Michail P. Rekalo and Egle Tomasi-Gustafsson | Associative charm photoproduction with circularly polarized photons | Add details on previously published model | Phys.Lett. B541 (2002) 101-107 | 10.1016/S0370-2693(02)02190-1 | null | hep-ph | null | We calculate the asymmetries for the processes $\vec\gamma+\vec p\to
\Lambda_c^+ (\Sigma_c^+)+\bar{D^0}$ and $\vec\gamma+\vec p\to \Lambda_c^+
(\Sigma_c^+)+\bar{D^*}$, induced by circularly polarized photons on a polarized
proton target in the framework of an effective Lagrangian model. We found large
and positive values for the asymmetry induced by the $z-$component of the
proton polarization, in a wide energy region, from threshold up to
$E_\gamma=70$ GeV. In the case of pseudoscalar meson photoproduction, the
predictions are qualitatively model-independent. For $D^*$-photoproduction,
there is a strong dependence of the asymmetries on $N\Lambda_c D(D^*)$-coupling
constants.
| [
{
"created": "Sat, 23 Feb 2002 16:13:55 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Apr 2002 13:14:59 GMT",
"version": "v2"
},
{
"created": "Fri, 31 May 2002 14:05:38 GMT",
"version": "v3"
}
] | 2009-11-07 | [
[
"Rekalo",
"Michail P.",
""
],
[
"Tomasi-Gustafsson",
"Egle",
""
]
] | We calculate the asymmetries for the processes $\vec\gamma+\vec p\to \Lambda_c^+ (\Sigma_c^+)+\bar{D^0}$ and $\vec\gamma+\vec p\to \Lambda_c^+ (\Sigma_c^+)+\bar{D^*}$, induced by circularly polarized photons on a polarized proton target in the framework of an effective Lagrangian model. We found large and positive values for the asymmetry induced by the $z-$component of the proton polarization, in a wide energy region, from threshold up to $E_\gamma=70$ GeV. In the case of pseudoscalar meson photoproduction, the predictions are qualitatively model-independent. For $D^*$-photoproduction, there is a strong dependence of the asymmetries on $N\Lambda_c D(D^*)$-coupling constants. |
hep-ph/9803474 | Andrej Arbuzov | A.B. Arbuzov, E.A. Kuraev (JINR, Dubna), F.F. Tikhonin (IHEP,
Protvino) B.G. Shaikhatdenov (JINR, Dubna) | Radiative corrections to the process $\mu^+ \mu^- \to H \gamma$ | 7 pages, LaTeX2e, 1 PostScript figure, misprints corrected, submitted
to Yad. Fiz | Phys.Atom.Nucl. 62 (1999) 1393-1396; Yad.Fiz. 62 (1999) 1477-1480 | null | null | hep-ph | null | QED radiative corrections to the cross-section of muon-antimuon annihilation
into Higgs boson and photon are calculated within the 1-loop approximation. We
write down the expression for cross-section in the form of Drell-Yan process,
taking into account higher order leading logs. The non-singlet structure
functions of fermions are shown to obey here evolution equations of twist-3
operators. Numerical estimation shows an importance of the correction in the
region close to the threshold of Higgs production.
| [
{
"created": "Fri, 27 Mar 1998 12:41:22 GMT",
"version": "v1"
},
{
"created": "Sat, 11 Apr 1998 14:31:02 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Arbuzov",
"A. B.",
"",
"JINR, Dubna"
],
[
"Kuraev",
"E. A.",
"",
"JINR, Dubna"
],
[
"Tikhonin",
"F. F.",
"",
"IHEP,\n Protvino"
],
[
"Shaikhatdenov",
"B. G.",
"",
"JINR, Dubna"
]
] | QED radiative corrections to the cross-section of muon-antimuon annihilation into Higgs boson and photon are calculated within the 1-loop approximation. We write down the expression for cross-section in the form of Drell-Yan process, taking into account higher order leading logs. The non-singlet structure functions of fermions are shown to obey here evolution equations of twist-3 operators. Numerical estimation shows an importance of the correction in the region close to the threshold of Higgs production. |
2104.01339 | Kang Xian-Wei | Jie-Cheng Feng, Xian-Wei Kang, Qi-Fang L\"u, Feng-Shou Zhang | Possible Assignment of Excited Light $^3S_1$ Vector Mesons | 10 pages, 9 tables, 6 figures, accepted for publication in PRD | Phys. Rev. D 104, 054027 (2021) | 10.1103/PhysRevD.104.054027 | null | hep-ph hep-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | We reanalyze the problems in the assignment of 3$^3S_1$ and 4$^3S_1$ light
mesons, which have not yet been well established with the $q\bar{q}$ quark
model. Regge trajectories and the $^3P_0$ decay model are used respectively to
study the mass and width of the observed states and predict the missing ones.
By comparing our calculations with the latest experiments, we suggest that the
inconsistent data of $\rho(2150)$ may include two similar structures
$\rho(4^3S_1)$ and $\omega(4^3S_1)$. In addition, the problem of the
$K^*(2^3S_1)$ assignment, with two observed states $K^*(1410)$ and $K^*(1680)$,
is investigated, with several possible explanations.
| [
{
"created": "Sat, 3 Apr 2021 08:25:13 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Jul 2021 14:08:40 GMT",
"version": "v2"
},
{
"created": "Wed, 4 Aug 2021 02:31:40 GMT",
"version": "v3"
}
] | 2021-09-29 | [
[
"Feng",
"Jie-Cheng",
""
],
[
"Kang",
"Xian-Wei",
""
],
[
"Lü",
"Qi-Fang",
""
],
[
"Zhang",
"Feng-Shou",
""
]
] | We reanalyze the problems in the assignment of 3$^3S_1$ and 4$^3S_1$ light mesons, which have not yet been well established with the $q\bar{q}$ quark model. Regge trajectories and the $^3P_0$ decay model are used respectively to study the mass and width of the observed states and predict the missing ones. By comparing our calculations with the latest experiments, we suggest that the inconsistent data of $\rho(2150)$ may include two similar structures $\rho(4^3S_1)$ and $\omega(4^3S_1)$. In addition, the problem of the $K^*(2^3S_1)$ assignment, with two observed states $K^*(1410)$ and $K^*(1680)$, is investigated, with several possible explanations. |
hep-ph/9911299 | Yuri Dokshitzer | Yu.L. Dokshitzer | Perturbative QCD and Power Corrections | Invited talk at the International Conference ``Frontiers of Matter'',
Blois, France, June 1999 10 pages, 9 figures | null | null | null | hep-ph | null | A short review is given of the present status of the studies of genuine
confinement effects in multiple hadron production in hard processes
| [
{
"created": "Wed, 10 Nov 1999 11:39:26 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Nov 1999 12:38:20 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Dokshitzer",
"Yu. L.",
""
]
] | A short review is given of the present status of the studies of genuine confinement effects in multiple hadron production in hard processes |
1105.6364 | Christian Weiss | G. A. Miller, M. Strikman, C. Weiss | Realizing vector meson dominance with transverse charge densities | 14 pages, 12 figures | null | 10.1103/PhysRevC.84.045205 | NT@UW-11-08, JLAB-THY-11-1377 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The transverse charge density in a fast-moving nucleon is represented as a
dispersion integral of the imaginary part of the Dirac form factor in the
timelike region (spectral function). At a given transverse distance b the
integration effectively extends over energies in a range sqrt{t} ~< 1/b, with
exponential suppression of larger values. The transverse charge density at
peripheral distances thus acts as a low-pass filter for the spectral function
and allows one to select energy regions dominated by specific t-channel states,
corresponding to definite exchange mechanisms in the spacelike form factor. We
show that distances b ~ 0.5 - 1.5 fm in the isovector density are maximally
sensitive to the rho meson region, with only a ~10% contribution from
higher-mass states. Soft-pion exchange governed by chiral dynamics becomes
relevant only at larger distances. In the isoscalar density higher-mass states
beyond the omega are comparatively more important. The dispersion approach
suggests that the positive transverse charge density in the neutron at b ~ 1
fm, found previously in a Fourier analysis of spacelike form factor data, could
serve as a sensitive test of the the isoscalar strength in the ~1 GeV mass
region. In terms of partonic structure, the transverse densities in the vector
meson region b ~ 1 fm support an approximate mean-field picture of the motion
of valence quarks in the nucleon.
| [
{
"created": "Tue, 31 May 2011 19:15:54 GMT",
"version": "v1"
}
] | 2013-05-29 | [
[
"Miller",
"G. A.",
""
],
[
"Strikman",
"M.",
""
],
[
"Weiss",
"C.",
""
]
] | The transverse charge density in a fast-moving nucleon is represented as a dispersion integral of the imaginary part of the Dirac form factor in the timelike region (spectral function). At a given transverse distance b the integration effectively extends over energies in a range sqrt{t} ~< 1/b, with exponential suppression of larger values. The transverse charge density at peripheral distances thus acts as a low-pass filter for the spectral function and allows one to select energy regions dominated by specific t-channel states, corresponding to definite exchange mechanisms in the spacelike form factor. We show that distances b ~ 0.5 - 1.5 fm in the isovector density are maximally sensitive to the rho meson region, with only a ~10% contribution from higher-mass states. Soft-pion exchange governed by chiral dynamics becomes relevant only at larger distances. In the isoscalar density higher-mass states beyond the omega are comparatively more important. The dispersion approach suggests that the positive transverse charge density in the neutron at b ~ 1 fm, found previously in a Fourier analysis of spacelike form factor data, could serve as a sensitive test of the the isoscalar strength in the ~1 GeV mass region. In terms of partonic structure, the transverse densities in the vector meson region b ~ 1 fm support an approximate mean-field picture of the motion of valence quarks in the nucleon. |
1901.09761 | Jaume Tarr\'us Castell\`a | Jaume Tarr\'us Castell\`a | Heavy hybrids and tetraquarks in effective field theory | Invited plenary talk at the 9th International Workshop on Charm
Physics. 8 pages, 3 figures | null | 10.1051/epjconf/201920201005 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We report on an effective field theory (EFT) description of exotic quarkonia
as bound states on the spectrum of hybrid and tetraquark static energies. We
provide expressions for hybrid and tetraquark static energies in terms of
Wilson loops. The former have been computed in quenched lattice calculations
but the latter are yet unavailable. From the few simulations with dynamical
light-quarks we argue that the overall picture from hybrid static energies does
not change but additional states, such as heavy meson pairs, need to be
considered for a full description. In this EFT framework for quarkonium
hybrids, we report on recent results for mixing with standard quarkonium,
spin-dependent contributions, and semi-inclusive decays.
| [
{
"created": "Mon, 28 Jan 2019 16:07:06 GMT",
"version": "v1"
}
] | 2019-05-01 | [
[
"Castellà",
"Jaume Tarrús",
""
]
] | We report on an effective field theory (EFT) description of exotic quarkonia as bound states on the spectrum of hybrid and tetraquark static energies. We provide expressions for hybrid and tetraquark static energies in terms of Wilson loops. The former have been computed in quenched lattice calculations but the latter are yet unavailable. From the few simulations with dynamical light-quarks we argue that the overall picture from hybrid static energies does not change but additional states, such as heavy meson pairs, need to be considered for a full description. In this EFT framework for quarkonium hybrids, we report on recent results for mixing with standard quarkonium, spin-dependent contributions, and semi-inclusive decays. |
2210.09886 | Adrian Abac | James David M. Tu\~nacao, Adrian G. Abac, Roland Emerito S. Otadoy | Finite Temperature Considerations in the Structure of Quadratic
GUP-modified White Dwarfs | null | International Journal of Modern Physics D Vol. 32, No. 08, 2350049
(2023) | 10.1142/S0218271823500499 | null | hep-ph astro-ph.SR gr-qc | http://creativecommons.org/licenses/by/4.0/ | In quantum gravity phenomenology, the effect of the generalized uncertainty
principle (GUP) on white dwarfs has been given much attention in the
literature. However, these studies assume a zero temperature equation of state
(EoS), consequently excluding young white dwarfs whose initial temperatures are
substantially high. To that cause, this paper calculates the Chandrasekhar EoS
and resulting mass-radius relations of finite temperature white dwarfs modified
by the quadratic GUP, an approach that extends Heisenberg's uncertainty
principle by a quadratic term in momenta. The EoS was first approximated by
treating the quadratic GUP parameter as perturbative, causing the EoS to
exhibit expected thermal deviations at low pressures, and conflicting behaviors
at high pressures, depending on the order of approximation. We then proceeded
with a full numerical simulation of the modified EoS, and showed that in
general, finite temperatures cause the EoS at low pressures to soften, while
the quadratic GUP stiffens the EoS at high pressures. This modified EoS was
then applied to the Tolman-Oppenheimer-Volkoff equations and its classical
approximation to obtain the modified mass-radius relations for general
relativistic and Newtonian white dwarfs. The relations for both cases were
found to exhibit the expected thermal deviations at small masses, where
low-mass white dwarfs are shifted to the high-mass regime at large radii, while
high-mass white dwarfs acquire larger masses, beyond the Chandrasekhar limit.
Additionally, we find that for sufficiently large values of the GUP parameter
and temperature, we obtain mass-radius relations that are completely removed
from the ideal case, as high-mass deviations due to GUP and low-mass deviations
due to temperature are no longer mutually exclusive.
| [
{
"created": "Tue, 18 Oct 2022 14:22:44 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Oct 2022 14:07:22 GMT",
"version": "v2"
},
{
"created": "Thu, 27 Apr 2023 09:29:48 GMT",
"version": "v3"
}
] | 2023-07-12 | [
[
"Tuñacao",
"James David M.",
""
],
[
"Abac",
"Adrian G.",
""
],
[
"Otadoy",
"Roland Emerito S.",
""
]
] | In quantum gravity phenomenology, the effect of the generalized uncertainty principle (GUP) on white dwarfs has been given much attention in the literature. However, these studies assume a zero temperature equation of state (EoS), consequently excluding young white dwarfs whose initial temperatures are substantially high. To that cause, this paper calculates the Chandrasekhar EoS and resulting mass-radius relations of finite temperature white dwarfs modified by the quadratic GUP, an approach that extends Heisenberg's uncertainty principle by a quadratic term in momenta. The EoS was first approximated by treating the quadratic GUP parameter as perturbative, causing the EoS to exhibit expected thermal deviations at low pressures, and conflicting behaviors at high pressures, depending on the order of approximation. We then proceeded with a full numerical simulation of the modified EoS, and showed that in general, finite temperatures cause the EoS at low pressures to soften, while the quadratic GUP stiffens the EoS at high pressures. This modified EoS was then applied to the Tolman-Oppenheimer-Volkoff equations and its classical approximation to obtain the modified mass-radius relations for general relativistic and Newtonian white dwarfs. The relations for both cases were found to exhibit the expected thermal deviations at small masses, where low-mass white dwarfs are shifted to the high-mass regime at large radii, while high-mass white dwarfs acquire larger masses, beyond the Chandrasekhar limit. Additionally, we find that for sufficiently large values of the GUP parameter and temperature, we obtain mass-radius relations that are completely removed from the ideal case, as high-mass deviations due to GUP and low-mass deviations due to temperature are no longer mutually exclusive. |
0904.0998 | Markus Ahlers | Markus Ahlers | The Hubble diagram as a probe of mini-charged particles | 4 pages, 3 figures | Phys.Rev.D80:023513,2009 | 10.1103/PhysRevD.80.023513 | OUTP-0908P | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The luminosity-redshift relation of cosmological standard candles provides
information about the relative energy composition of our Universe. In
particular, the observation of type Ia supernovae up to redshift of z~2
indicate a universe which is dominated today by dark matter and dark energy.
The propagation distance of light from these sources is of the order of the
Hubble radius and serves as a very sensitive probe of feeble inelastic photon
interactions with background matter, radiation or magnetic fields. In this
paper we discuss the limits on mini-charged particle models arising from a
dimming effect in supernova surveys. We briefly speculate about a strong
dimming effect as an alternative to dark energy.
| [
{
"created": "Tue, 7 Apr 2009 08:46:34 GMT",
"version": "v1"
}
] | 2009-09-02 | [
[
"Ahlers",
"Markus",
""
]
] | The luminosity-redshift relation of cosmological standard candles provides information about the relative energy composition of our Universe. In particular, the observation of type Ia supernovae up to redshift of z~2 indicate a universe which is dominated today by dark matter and dark energy. The propagation distance of light from these sources is of the order of the Hubble radius and serves as a very sensitive probe of feeble inelastic photon interactions with background matter, radiation or magnetic fields. In this paper we discuss the limits on mini-charged particle models arising from a dimming effect in supernova surveys. We briefly speculate about a strong dimming effect as an alternative to dark energy. |
hep-ph/0506325 | Philippe Ruelle | P. Artoisenet, J.-M. Gerard and J. Weyers | Survival before annihilation in Psi-prime decays | 6 pages, no figure | Phys.Lett.B628:211-214,2005 | 10.1016/j.physletb.2005.09.041 | UCL-IPT-05-02 | hep-ph hep-ex | null | We extend the simple scenario for $\Psi'$ decays suggested a few years ago.
The $c\bar c$ pair in the $\Psi'$ does not annihilate directly into three
gluons but rather survives before annihilating. An interesting prediction is
that a large fraction of all $\Psi'$ decays could originate from the $\Psi' \to
\eta_{c} (3\pi)$ channel which we urge experimentalists to identify. Our model
solves the problem of the apparent hadronic excess in $\Psi'$ decays as well as
the $\rho\pi$ puzzle since, in our view, the two-body decays of the $\Psi'$ are
naturally of electromagnetic origin. Further tests of this picture are
proposed, e.g. $J/\Psi \to b_{1}\eta$.
| [
{
"created": "Thu, 30 Jun 2005 14:10:27 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Artoisenet",
"P.",
""
],
[
"Gerard",
"J. -M.",
""
],
[
"Weyers",
"J.",
""
]
] | We extend the simple scenario for $\Psi'$ decays suggested a few years ago. The $c\bar c$ pair in the $\Psi'$ does not annihilate directly into three gluons but rather survives before annihilating. An interesting prediction is that a large fraction of all $\Psi'$ decays could originate from the $\Psi' \to \eta_{c} (3\pi)$ channel which we urge experimentalists to identify. Our model solves the problem of the apparent hadronic excess in $\Psi'$ decays as well as the $\rho\pi$ puzzle since, in our view, the two-body decays of the $\Psi'$ are naturally of electromagnetic origin. Further tests of this picture are proposed, e.g. $J/\Psi \to b_{1}\eta$. |
hep-ph/0504241 | Michal Malinsky | Stefano Bertolini, Michal Malinsky | On CP Violation in Minimal Renormalizable SUSY SO(10) and Beyond | 9 pages, 6 figures. Two refs added, discussion expanded. To appear on
Phys. Rev. D | Phys.Rev. D72 (2005) 055021 | 10.1103/PhysRevD.72.055021 | null | hep-ph | null | We investigate the role of CP phases within the renormalizable SUSY SO(10)
GUT with one 10_H, one 126bar_H one 126_H and one 210_H Higgs representations
and type II seesaw dominating the neutrino mass matrix. This framework is non
trivially predictive in the fermionic sector and connects in a natural way the
GUT unification of b and tau Yukawa couplings with the bi-large mixing scenario
for neutrinos. On the other hand, existing numerical analysis claim that
consistency with quark and charged lepton data prevents the minimal setup from
reproducing the observed CP violation via the Cabibbo-Kobayashi-Maskawa (CKM)
matrix. We re-examine the issue and find by inspection of the fermion mass sum
rules and a detailed numerical scan that, even though the CKM phase takes
preferentially values in the second quadrant, the agreement of the minimal
model with the data is actually obtained in a non negligible fraction of the
parameter space. We then consider a recently proposed renormalizable extension
of the minimal model, obtained by adding one chiral 120-dimensional Higgs
supermultiplet. We show that within such a setup the CKM phase falls naturally
in the observed range. We emphazise the robust predictivity of both models here
considered for neutrino parameters that are in the reach of ongoing and future
experiments.
| [
{
"created": "Tue, 26 Apr 2005 14:48:18 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Apr 2005 20:21:59 GMT",
"version": "v2"
},
{
"created": "Tue, 24 May 2005 12:32:59 GMT",
"version": "v3"
},
{
"created": "Mon, 5 Sep 2005 07:54:16 GMT",
"version": "v4"
}
] | 2009-11-11 | [
[
"Bertolini",
"Stefano",
""
],
[
"Malinsky",
"Michal",
""
]
] | We investigate the role of CP phases within the renormalizable SUSY SO(10) GUT with one 10_H, one 126bar_H one 126_H and one 210_H Higgs representations and type II seesaw dominating the neutrino mass matrix. This framework is non trivially predictive in the fermionic sector and connects in a natural way the GUT unification of b and tau Yukawa couplings with the bi-large mixing scenario for neutrinos. On the other hand, existing numerical analysis claim that consistency with quark and charged lepton data prevents the minimal setup from reproducing the observed CP violation via the Cabibbo-Kobayashi-Maskawa (CKM) matrix. We re-examine the issue and find by inspection of the fermion mass sum rules and a detailed numerical scan that, even though the CKM phase takes preferentially values in the second quadrant, the agreement of the minimal model with the data is actually obtained in a non negligible fraction of the parameter space. We then consider a recently proposed renormalizable extension of the minimal model, obtained by adding one chiral 120-dimensional Higgs supermultiplet. We show that within such a setup the CKM phase falls naturally in the observed range. We emphazise the robust predictivity of both models here considered for neutrino parameters that are in the reach of ongoing and future experiments. |
1711.10859 | P\'eter Kov\'acs Dr. | P\'eter Kov\'acs, Gy\"orgy Wolf | Phase diagram and isentropic curves from the vector meson extended
Polyakov quark meson model | 6 pages, 4 figures, Presented at Excited QCD 2017, 7-13 May 2017,
Sintra, Portugal | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of the $N_f = 2+1$ flavor (axial)vector meson extended
Polyakov quark meson model we investigate the QCD phase diagram at finite
temperature and density. We use a $\chi^2$ minimization procedure to
parameterize the model based on tree\,-\,level decay widths and vacuum scalar
and pseudoscalar curvature masses which incorporate the contribution of the
constituent quarks. Using a hybrid approximation (mesons at tree level,
fermions at one\,-\,loop level) for the grand potential we determine the phase
boundary both on the $\mu_B-T$ and $\rho-T$ planes. We also determine the
location of the critical end point of the phase diagram. Moreover by
calculating the pressure and other thermodynamical quantities derived from it,
we determine a set of isentropic curves in the crossover region. We show that
the curves behave very similarly as their counterparts obtained from the
lattice in the crossover regime.
| [
{
"created": "Wed, 29 Nov 2017 14:06:57 GMT",
"version": "v1"
}
] | 2017-11-30 | [
[
"Kovács",
"Péter",
""
],
[
"Wolf",
"György",
""
]
] | In the framework of the $N_f = 2+1$ flavor (axial)vector meson extended Polyakov quark meson model we investigate the QCD phase diagram at finite temperature and density. We use a $\chi^2$ minimization procedure to parameterize the model based on tree\,-\,level decay widths and vacuum scalar and pseudoscalar curvature masses which incorporate the contribution of the constituent quarks. Using a hybrid approximation (mesons at tree level, fermions at one\,-\,loop level) for the grand potential we determine the phase boundary both on the $\mu_B-T$ and $\rho-T$ planes. We also determine the location of the critical end point of the phase diagram. Moreover by calculating the pressure and other thermodynamical quantities derived from it, we determine a set of isentropic curves in the crossover region. We show that the curves behave very similarly as their counterparts obtained from the lattice in the crossover regime. |
hep-ph/0003119 | Jon Rosner | Michael Gronau and Jonathan L. Rosner | The Role of $B_s \to K \pi$ in Determining the Weak Phase $\gamma$ | 8 pages, LaTeX, no figures, submitted to Physics Letters B,
corrections to discussion of SU(3) breaking added | Phys.Lett.B482:71-76,2000 | 10.1016/S0370-2693(00)00508-6 | TECHNION-PH-00-25, EFI 2000-8 | hep-ph | null | The decay rates for $B^0 \to K^+ \pi^-$, $B^+ \to K^0 \pi^+$, and the
charge-conjugate processes were found to provide information on the weak phase
$\gamma \equiv {\rm Arg}(V_{ub}^*)$ when the ratio $r$ of weak tree and penguin
amplitudes was taken from data on $B \to \pi \pi$ or semileptonic $B \to \pi$
decays. We show here that the rates for $B_s \to K^- \pi^+$ and $\bar B_s \to
K^+ \pi^-$ can provide the necessary information on $r$, and estimate the
statistical accuracy of forthcoming measurements at the Fermilab Tevatron.
| [
{
"created": "Mon, 13 Mar 2000 17:51:30 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Mar 2000 17:46:29 GMT",
"version": "v2"
},
{
"created": "Mon, 20 Mar 2000 16:54:12 GMT",
"version": "v3"
},
{
"created": "Wed, 22 Mar 2000 16:37:59 GMT",
"version": "v4"
}
] | 2014-11-17 | [
[
"Gronau",
"Michael",
""
],
[
"Rosner",
"Jonathan L.",
""
]
] | The decay rates for $B^0 \to K^+ \pi^-$, $B^+ \to K^0 \pi^+$, and the charge-conjugate processes were found to provide information on the weak phase $\gamma \equiv {\rm Arg}(V_{ub}^*)$ when the ratio $r$ of weak tree and penguin amplitudes was taken from data on $B \to \pi \pi$ or semileptonic $B \to \pi$ decays. We show here that the rates for $B_s \to K^- \pi^+$ and $\bar B_s \to K^+ \pi^-$ can provide the necessary information on $r$, and estimate the statistical accuracy of forthcoming measurements at the Fermilab Tevatron. |
hep-ph/0701084 | Mohammad M. Sheikh-Jabbari | M. M. Sheikh-Jabbari | An N-tropic Solution to the Cosmological Constant Problem | 4 pages, Presented at IPM School and Conference on Lepton and Hadron
Physics (IPM-LHP06), Tehran, Iran, 15-20 May 2006 and also in ICHEP'06,
Moscow, Russia | ECONF C0605151:0023,2006 | null | null | hep-ph gr-qc hep-th | null | Based on the assertion that the cosmological constant problem is essentially
a quantum gravity problem, the framework which addresses the cosmological
constant problem should also bear a picture for the ``quantum space-time''. In
this talk in an attempt to address the cosmological constant problem I suggest
to start with noncommutative fuzzy spheres as the toy model for the quantum
space-time. In this setting, we show that the cosmological constant problem may
be resolved due to the noncommutativity and ``fuzziness'' of the space and the
fact that the smallest volume which could be measured in the a quantum
space-time is much larger than the naively expected Planckian size. This talk
is based on Ref.[1] which has appeared on the arXiv as hep-th/0605110.
| [
{
"created": "Thu, 11 Jan 2007 10:12:59 GMT",
"version": "v1"
}
] | 2009-10-07 | [
[
"Sheikh-Jabbari",
"M. M.",
""
]
] | Based on the assertion that the cosmological constant problem is essentially a quantum gravity problem, the framework which addresses the cosmological constant problem should also bear a picture for the ``quantum space-time''. In this talk in an attempt to address the cosmological constant problem I suggest to start with noncommutative fuzzy spheres as the toy model for the quantum space-time. In this setting, we show that the cosmological constant problem may be resolved due to the noncommutativity and ``fuzziness'' of the space and the fact that the smallest volume which could be measured in the a quantum space-time is much larger than the naively expected Planckian size. This talk is based on Ref.[1] which has appeared on the arXiv as hep-th/0605110. |
0907.2256 | Emi Kou | Sebastien Descotes-Genon, Jibo He, Emi Kou and Patrick Robbe | Non-leptonic charmless Bc decays and their search at LHCb | 22 pages, 1 figure | Phys.Rev.D80:114031,2009 | 10.1103/PhysRevD.80.114031 | LPT-ORSAY-09-14, LAL-09-28 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the decay of Bc mesons into two light mesons (pi, K^(*), eta',
rho, omega, phi). All these decay channels come from a single type of diagram,
namely tree annihilation. This allows us to derive extremely simple SU(3)
relations among these processes. The size of annihilation contributions is an
important issue in B physics, and we provide two different estimates in the
case of non-leptonic charmless Bc decays, either a comparison with annihilation
decays of heavy-light mesons or a perturbative model inspired by QCD
factorisation. We finally discuss a possible search for these channels at LHCb.
| [
{
"created": "Mon, 13 Jul 2009 22:04:39 GMT",
"version": "v1"
}
] | 2010-01-08 | [
[
"Descotes-Genon",
"Sebastien",
""
],
[
"He",
"Jibo",
""
],
[
"Kou",
"Emi",
""
],
[
"Robbe",
"Patrick",
""
]
] | We discuss the decay of Bc mesons into two light mesons (pi, K^(*), eta', rho, omega, phi). All these decay channels come from a single type of diagram, namely tree annihilation. This allows us to derive extremely simple SU(3) relations among these processes. The size of annihilation contributions is an important issue in B physics, and we provide two different estimates in the case of non-leptonic charmless Bc decays, either a comparison with annihilation decays of heavy-light mesons or a perturbative model inspired by QCD factorisation. We finally discuss a possible search for these channels at LHCb. |
hep-ph/0503219 | Sangyong Jeon | Sangyong Jeon and Raju Venugopalan | A classical Odderon in QCD at high energies | 19 pages. No figure | Phys.Rev.D71:125003,2005 | 10.1103/PhysRevD.71.125003 | null | hep-ph hep-th nucl-th | null | We show that the weight functional for color sources in the classical theory
of the Color Glass Condensate includes a term which generates Odderon
excitations. Remarkably, the classical origin of these excitations can be
traced to the random walk of partons in the two dimensional space spanned by
the SU(3) Casimirs. This term is naturally suppressed for a large nucleus at
high energies.
| [
{
"created": "Tue, 22 Mar 2005 17:05:46 GMT",
"version": "v1"
}
] | 2010-11-30 | [
[
"Jeon",
"Sangyong",
""
],
[
"Venugopalan",
"Raju",
""
]
] | We show that the weight functional for color sources in the classical theory of the Color Glass Condensate includes a term which generates Odderon excitations. Remarkably, the classical origin of these excitations can be traced to the random walk of partons in the two dimensional space spanned by the SU(3) Casimirs. This term is naturally suppressed for a large nucleus at high energies. |
hep-ph/9308304 | Youichi Yamada | Youichi Yamada | Two-loop renormalization of gaugino masses in general supersymmetric
gauge models | 8 pages + 1 figure (omitted),KEK-TH-371 / UT-653 | Phys.Rev.Lett. 72 (1994) 25-27 | 10.1103/PhysRevLett.72.25 | null | hep-ph | null | We calculate the two-loop renormalization group equations for the running
gaugino masses in general SUSY gauge models, improving our previous result. We
also study its consequence to the unification of the gaugino masses in the SUSY
SU(5) model. The two-loop correction to the one-loop relation
$m_i(\mu)\propto\alpha_i(\mu)$ is found to be of the order of a few \%.
| [
{
"created": "Fri, 20 Aug 1993 01:45:57 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Yamada",
"Youichi",
""
]
] | We calculate the two-loop renormalization group equations for the running gaugino masses in general SUSY gauge models, improving our previous result. We also study its consequence to the unification of the gaugino masses in the SUSY SU(5) model. The two-loop correction to the one-loop relation $m_i(\mu)\propto\alpha_i(\mu)$ is found to be of the order of a few \%. |
0903.1427 | Qiang Zhao | Xiao-Hai Liu, Yuan-Jiang Zhang and Qiang Zhao | A possible mechanism for producing the threshold enhancement in
$J/\psi\to\gamma p\bar{p}$ | Revtex4, 8 pages, 5 eps figures; Revised version with additional
supportive results on pp-bar to VV; To appear in Phys. Rev. D | Phys.Rev.D80:034032,2009 | 10.1103/PhysRevD.80.034032 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the $J/\psi$ radiative decay channels $J/\psi\to \gamma V\bar{V}$, the
result of partial wave analysis indicates that the $V\bar{V}$ systems are
predominately pseudoscalar component, and most of these channels have
relatively large branching ratios at an order of $10^{-3}$. Meanwhile, vector
mesons, such as $\rho$, $\omega$ and $K^*$, have strong couplings with nucleons
and/or hyperons. This suggests a dynamical mechanism describing the $\eta
p\bar{p}$ form factors for higher $\eta$ mesons, such as $\eta(1405/1475)$ and
$\eta(1760)$. It is thus natural to expect that rescatterings of these vector
meson pairs into $p\bar{p}$ of $0^-$ partial wave could be an important source
contributing to $J/\psi\to\gamma p\bar{p}$ of which the branching ratio is at
the order of $10^{-4}$. Our calculation justifies this point. In particular, we
find that interferences between different rescattering amplitudes can produce a
significant threshold enhancement in the invariant mass spectrum of $p\bar{p}$.
Without introducing dramatic ingredients, our model provides a natural
explanation for the peculiar threshold enhancement observed by BES-II in
$J/\psi\to \gamma p\bar{p}$. Additional experimental constraints on the
$V\bar{V}\to p\bar{p}$ transitions are examined. This mechanism in $J/\psi\to
\omega p\bar{p}$ is also discussed.
| [
{
"created": "Mon, 9 Mar 2009 02:59:57 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Aug 2009 19:49:04 GMT",
"version": "v2"
}
] | 2009-09-01 | [
[
"Liu",
"Xiao-Hai",
""
],
[
"Zhang",
"Yuan-Jiang",
""
],
[
"Zhao",
"Qiang",
""
]
] | In the $J/\psi$ radiative decay channels $J/\psi\to \gamma V\bar{V}$, the result of partial wave analysis indicates that the $V\bar{V}$ systems are predominately pseudoscalar component, and most of these channels have relatively large branching ratios at an order of $10^{-3}$. Meanwhile, vector mesons, such as $\rho$, $\omega$ and $K^*$, have strong couplings with nucleons and/or hyperons. This suggests a dynamical mechanism describing the $\eta p\bar{p}$ form factors for higher $\eta$ mesons, such as $\eta(1405/1475)$ and $\eta(1760)$. It is thus natural to expect that rescatterings of these vector meson pairs into $p\bar{p}$ of $0^-$ partial wave could be an important source contributing to $J/\psi\to\gamma p\bar{p}$ of which the branching ratio is at the order of $10^{-4}$. Our calculation justifies this point. In particular, we find that interferences between different rescattering amplitudes can produce a significant threshold enhancement in the invariant mass spectrum of $p\bar{p}$. Without introducing dramatic ingredients, our model provides a natural explanation for the peculiar threshold enhancement observed by BES-II in $J/\psi\to \gamma p\bar{p}$. Additional experimental constraints on the $V\bar{V}\to p\bar{p}$ transitions are examined. This mechanism in $J/\psi\to \omega p\bar{p}$ is also discussed. |
2210.13187 | Slava Khruschov | K. A. Bronnikov, V. D. Ivashchuk, V. V. Khruschov | Fundamental physical constants: current results in search for variations
and their description | 8 pages | Measurement Techniques, 2022, Vol. 65, No. 3, P. 151-156 | 10.1007/s11018-022-02062-z | null | hep-ph gr-qc | http://creativecommons.org/licenses/by/4.0/ | We consider the current results in search for and description of temporal
variations of fundamental physical constants (FPCs) obtained under laboratory
and astrophysical conditions. On the basis of fixed values of base constants,
those FPCs have been chosen that can exhibit variations of greatest interest
from the viewpoints of physics and metrology. An analysis of the current data
concerning these constants is performed, and estimates of their variations on
large time scales are presented. We point out the significance of studying
long-term FPC variations for both practical and fundamental metrology.
| [
{
"created": "Fri, 21 Oct 2022 06:56:16 GMT",
"version": "v1"
}
] | 2022-10-25 | [
[
"Bronnikov",
"K. A.",
""
],
[
"Ivashchuk",
"V. D.",
""
],
[
"Khruschov",
"V. V.",
""
]
] | We consider the current results in search for and description of temporal variations of fundamental physical constants (FPCs) obtained under laboratory and astrophysical conditions. On the basis of fixed values of base constants, those FPCs have been chosen that can exhibit variations of greatest interest from the viewpoints of physics and metrology. An analysis of the current data concerning these constants is performed, and estimates of their variations on large time scales are presented. We point out the significance of studying long-term FPC variations for both practical and fundamental metrology. |
0712.2681 | Chen Jacoby | Chen Jacoby and Shmuel Nussinov | The Relic Abundance of Massive Colored Particles after a Late Hadronic
Annihilation Stage | 28 pages, 2 figures | null | null | TAUP-2867-07 | hep-ph astro-ph | null | We discuss the relic abundance of massive long lived colored particles with
mass of the order of 1 TeV. We first examine the case where the massive colored
particles have the standard color only. Next we consider the "Quirk Model"
suggested by M. Luty, in which the colored particles transform under an
additional non-abelian gauge group with a scale much smaller than the
particles' mass. In both cases, the relic abundance is reduced via a "late"
hadronic annihilation stage. In the second case the relic Quirks bind to
ordinary quarks forming fractional charged objects and also anomalous heavy
isotopes, and the bounds on the relic abundance become extremely severe. The
force between Quirks, however, has a new confining part that manifests via
macroscopic strings and the resulting efficient "very late" annihilations
reduce the relic abundance to acceptable levels. The prospects of creating and
detecting such particles at LHC and the fate of the particles created are
discussed.
| [
{
"created": "Mon, 17 Dec 2007 11:07:26 GMT",
"version": "v1"
}
] | 2007-12-18 | [
[
"Jacoby",
"Chen",
""
],
[
"Nussinov",
"Shmuel",
""
]
] | We discuss the relic abundance of massive long lived colored particles with mass of the order of 1 TeV. We first examine the case where the massive colored particles have the standard color only. Next we consider the "Quirk Model" suggested by M. Luty, in which the colored particles transform under an additional non-abelian gauge group with a scale much smaller than the particles' mass. In both cases, the relic abundance is reduced via a "late" hadronic annihilation stage. In the second case the relic Quirks bind to ordinary quarks forming fractional charged objects and also anomalous heavy isotopes, and the bounds on the relic abundance become extremely severe. The force between Quirks, however, has a new confining part that manifests via macroscopic strings and the resulting efficient "very late" annihilations reduce the relic abundance to acceptable levels. The prospects of creating and detecting such particles at LHC and the fate of the particles created are discussed. |
2208.06252 | Francesco Giovanni Celiberto | Alessandro Bacchetta, Francesco Giovanni Celiberto, Marco Radici,
Andrea Signori | Phenomenology of gluon TMDs from $\eta_{b,c}$ production | 7 pages, 1 figure. Presented by F.G. Celiberto at DIS2022: XXIX
International Workshop on Deep-Inelastic Scattering and Related Subjects,
Santiago de Compostela, Spain, May 2-6 2022 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the potential of $\eta_{b,c}$ production in proton collisions to
access the gluon transverse-momentum dependent parton distributions (TMDs). In
particular, we explore the phenomenology of the unpolarized and
linearly-polarized gluon TMDs in unpolarized collisions for different kinematic
settings, and the potential of a fixed-target experiment at the LHC.
| [
{
"created": "Fri, 12 Aug 2022 13:01:27 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Aug 2022 13:42:24 GMT",
"version": "v2"
}
] | 2022-08-17 | [
[
"Bacchetta",
"Alessandro",
""
],
[
"Celiberto",
"Francesco Giovanni",
""
],
[
"Radici",
"Marco",
""
],
[
"Signori",
"Andrea",
""
]
] | We present the potential of $\eta_{b,c}$ production in proton collisions to access the gluon transverse-momentum dependent parton distributions (TMDs). In particular, we explore the phenomenology of the unpolarized and linearly-polarized gluon TMDs in unpolarized collisions for different kinematic settings, and the potential of a fixed-target experiment at the LHC. |
hep-ph/9712347 | S. Karshenboim | Savely G. Karshenboim (D. I. Mendeleev Institute for Metrology
(VNIIM), St. Petersburg) | What do we actually know on the proton radius ? | 24 pages, 5 figures, 5 tables | Can.J.Phys. 77 (1999) 241-266 | 10.1139/cjp-77-4-241 | null | hep-ph | null | The work is devoted to a consideration of the different determinations of the
proton charge radius. It is demonstrated that the results from the elastic
electron-proton scattering have to be of a higher uncertainty. A review of the
hydrogen Lamb shift measurements and the radius determination from them is also
presented.
| [
{
"created": "Thu, 11 Dec 1997 14:13:58 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Karshenboim",
"Savely G.",
"",
"D. I. Mendeleev Institute for Metrology"
]
] | The work is devoted to a consideration of the different determinations of the proton charge radius. It is demonstrated that the results from the elastic electron-proton scattering have to be of a higher uncertainty. A review of the hydrogen Lamb shift measurements and the radius determination from them is also presented. |
hep-ph/9604319 | Jonathan L. Rosner | Jonathan L. Rosner | Two Topics in $b$ Physics | 11 pages, latex, no figures. Presented at 10th La Thuile Rencontre.
DESY preprint no. corrected in heading | null | null | DESY-96-062, CERN-TH/96-100, EFI-96-11 | hep-ph | null | (1) A simple transversity analysis permits one to separate the P-even and
P-odd partial waves in such decays as $B_s \to J/\psi \phi$ and $B \to J/\psi
K^*$. This method is relevant to the separation of contributions of CP-even and
CP-odd final states in $B_s$ decays, and hence to the measurement of a possible
lifetime difference between mass eigenstates. (2) The enhancement $\Delta
\Gamma (\Lambda_b)$ of the $\Lambda_b$ decay rate due to four-fermion processes
is calculated in terms of the $\Sigma_b^* - \Sigma_b$ hyperfine splitting, the
$B^* - B$ hyperfine splitting, and the $B$ meson decay constant $f_B$. Despite
a relatively large hyperfine splitting observed by the DELPHI Collaboration,
the mechanism falls far short of being able to explain the observed
enhancement.
| [
{
"created": "Mon, 15 Apr 1996 09:33:04 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Apr 1996 08:27:33 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Rosner",
"Jonathan L.",
""
]
] | (1) A simple transversity analysis permits one to separate the P-even and P-odd partial waves in such decays as $B_s \to J/\psi \phi$ and $B \to J/\psi K^*$. This method is relevant to the separation of contributions of CP-even and CP-odd final states in $B_s$ decays, and hence to the measurement of a possible lifetime difference between mass eigenstates. (2) The enhancement $\Delta \Gamma (\Lambda_b)$ of the $\Lambda_b$ decay rate due to four-fermion processes is calculated in terms of the $\Sigma_b^* - \Sigma_b$ hyperfine splitting, the $B^* - B$ hyperfine splitting, and the $B$ meson decay constant $f_B$. Despite a relatively large hyperfine splitting observed by the DELPHI Collaboration, the mechanism falls far short of being able to explain the observed enhancement. |
1909.11242 | Avital Dery | Avital Dery and Yosef Nir | Implications of the LHCb discovery of CP violation in charm decays | null | null | 10.1007/JHEP12(2019)104 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recent measurement of $\Delta A_{CP}$ by the LHCb collaboration requires
an ${\cal O}(10)$ enhancement coming from hadronic physics in order to be
explained within the SM. We examine to what extent can NP models explain
$\Delta A_{CP}$ without such enhancements. We discuss the implications in terms
of a low energy effective theory as well as in the context of several explicit
NP models.
| [
{
"created": "Wed, 25 Sep 2019 00:44:07 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Nov 2019 16:23:54 GMT",
"version": "v2"
}
] | 2020-01-29 | [
[
"Dery",
"Avital",
""
],
[
"Nir",
"Yosef",
""
]
] | The recent measurement of $\Delta A_{CP}$ by the LHCb collaboration requires an ${\cal O}(10)$ enhancement coming from hadronic physics in order to be explained within the SM. We examine to what extent can NP models explain $\Delta A_{CP}$ without such enhancements. We discuss the implications in terms of a low energy effective theory as well as in the context of several explicit NP models. |
hep-ph/9304303 | Oleg | D.J.Broadhurst, J.Fleischer and O.V.Tarasov | Two-loop two-point functions with masses: asymptotic expansions and
Taylor series, in any dimension | 25 pages, OUT--4102--43, BI--TP/92--57 | Z.Phys.C60:287-302,1993 | 10.1007/BF01474625 | null | hep-ph | null | In all mass cases needed for quark and gluon self-energies, the two-loop
master diagram is expanded at large and small $q^2$, in $d$ dimensions, using
identities derived from integration by parts. Expansions are given, in terms of
hypergeometric series, for all gluon diagrams and for all but one of the quark
diagrams; expansions of the latter are obtained from differential equations.
Pad\'{e} approximants to truncations of the expansions are shown to be of great
utility. As an application, we obtain the two-loop photon self-energy, for all
$d$, and achieve highly accelerated convergence of its expansions in powers of
$q^2/m^2$ or $m^2/q^2$, for $d=4$.
| [
{
"created": "Tue, 27 Apr 1993 12:50:48 GMT",
"version": "v1"
}
] | 2011-08-17 | [
[
"Broadhurst",
"D. J.",
""
],
[
"Fleischer",
"J.",
""
],
[
"Tarasov",
"O. V.",
""
]
] | In all mass cases needed for quark and gluon self-energies, the two-loop master diagram is expanded at large and small $q^2$, in $d$ dimensions, using identities derived from integration by parts. Expansions are given, in terms of hypergeometric series, for all gluon diagrams and for all but one of the quark diagrams; expansions of the latter are obtained from differential equations. Pad\'{e} approximants to truncations of the expansions are shown to be of great utility. As an application, we obtain the two-loop photon self-energy, for all $d$, and achieve highly accelerated convergence of its expansions in powers of $q^2/m^2$ or $m^2/q^2$, for $d=4$. |
1311.1065 | Michael Eides | Michael I. Eides and Valery A. Shelyuto | Light-by-Light Scattering Nonlogarithmic Corrections to Hyperfine
Splitting in Muonium | Minor corrections, version to be published in Phys. Rev. D | Phys. Rev. D 89, 014034 (2014) | 10.1103/PhysRevD.89.014034 | UK/13-04 | hep-ph physics.atom-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider three-loop corrections to hyperfine splitting in muonium
generated by the gauge invariant set of diagrams with virtual light-by-light
scattering block. These diagrams produce both recoil and nonrecoil
contributions to hyperfine splitting. Recoil corrections are enhanced by large
logarithms of the muon-electron mass ratio. Both nonrecoil and logarithmically
enhanced radiative-recoil corrections where calculated some time ago. Here we
calculate nonlogarithmic radiative-recoil corrections generated by the
insertions of the light-by-light scattering block.
| [
{
"created": "Tue, 5 Nov 2013 14:24:46 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Nov 2013 11:54:41 GMT",
"version": "v2"
},
{
"created": "Thu, 16 Jan 2014 17:06:46 GMT",
"version": "v3"
}
] | 2014-02-05 | [
[
"Eides",
"Michael I.",
""
],
[
"Shelyuto",
"Valery A.",
""
]
] | We consider three-loop corrections to hyperfine splitting in muonium generated by the gauge invariant set of diagrams with virtual light-by-light scattering block. These diagrams produce both recoil and nonrecoil contributions to hyperfine splitting. Recoil corrections are enhanced by large logarithms of the muon-electron mass ratio. Both nonrecoil and logarithmically enhanced radiative-recoil corrections where calculated some time ago. Here we calculate nonlogarithmic radiative-recoil corrections generated by the insertions of the light-by-light scattering block. |
0907.4985 | David G. Cerdeno | D.G. Cerdeno, Y. Mambrini, A. Romagnoni | Gravitino dark matter in hybrid gauge-gravity models | LaTeX, 20 pages 3 figures | JHEP 0911:113,2009 | 10.1088/1126-6708/2009/11/113 | FTUAM 09/16, IFT-UAM/CSIC-09-32, CPHT-RR077.0709, LPT-Orsay 09/59 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the phenomenology of generic supergravity models in which gravity
mediation naturally competes with gauge mediation as the origin of
supergravity-breaking. This class of hybrid models has been recently motivated
in string inspired constructions and differs from usual gauge mediated
supersymmetry breaking models in having messenger masses of order of the GUT
scale. In these scenarios the gravitino can be the lightest supersymmetric
particle in wide regions of the parameter space and therefore a potential
candidate for dark matter. We investigate this possibility, imposing the WMAP
bound on its relic abundance and taking into account constraints from Big Bang
nucleosynthesis. We show that in these constructions viable gravitino dark
matter can be obtained in specific regions of the parameter space, featuring
large values of tan(beta) and where the supersymmetry breaking mechanism is
dominated by gauge mediation.
| [
{
"created": "Wed, 29 Jul 2009 11:43:05 GMT",
"version": "v1"
}
] | 2009-12-04 | [
[
"Cerdeno",
"D. G.",
""
],
[
"Mambrini",
"Y.",
""
],
[
"Romagnoni",
"A.",
""
]
] | We study the phenomenology of generic supergravity models in which gravity mediation naturally competes with gauge mediation as the origin of supergravity-breaking. This class of hybrid models has been recently motivated in string inspired constructions and differs from usual gauge mediated supersymmetry breaking models in having messenger masses of order of the GUT scale. In these scenarios the gravitino can be the lightest supersymmetric particle in wide regions of the parameter space and therefore a potential candidate for dark matter. We investigate this possibility, imposing the WMAP bound on its relic abundance and taking into account constraints from Big Bang nucleosynthesis. We show that in these constructions viable gravitino dark matter can be obtained in specific regions of the parameter space, featuring large values of tan(beta) and where the supersymmetry breaking mechanism is dominated by gauge mediation. |
2008.03139 | Maria Stefaniak | Maria Stefaniak, Daniel Kincses | Investigating the pion source function in heavy-ion collisions with the
EPOS model | 7 pages, 5 figures, Summer XLVI-th IEEE-SPIE Joint Symposium Wilga
2020 - conference proceedings | null | 10.1117/12.2580570 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By measuring the momentum correlations of pions created in heavy-ion
collisions we can gain information about the space-time geometry of the
particle emitting source. Recent experimental results from multiple different
collaborations demonstrated that to properly describe the shape of the measured
correlation functions, one needs to go beyond the Gaussian approximation. Some
studies suggest that the Levy distribution could provide a good description of
the source. While there are already many experimental results, there is very
little input from the phenomenology side in explanation of the observed
non-Gaussian source shapes. The EPOS model is a sophisticated hybrid model
where the evolution of the newly-created system is governed by Parton-Based
Gribov-Regge theory. It has already proved to be successful in describing many
different experimental observations for the systems characterized by baryon
chemical potential close to zero, but so far the source shape has not been
explored in detail. In this paper we discuss studies of the pion emitting
source based on the theoretical approach of the EPOS model.
| [
{
"created": "Fri, 7 Aug 2020 12:58:21 GMT",
"version": "v1"
}
] | 2020-10-30 | [
[
"Stefaniak",
"Maria",
""
],
[
"Kincses",
"Daniel",
""
]
] | By measuring the momentum correlations of pions created in heavy-ion collisions we can gain information about the space-time geometry of the particle emitting source. Recent experimental results from multiple different collaborations demonstrated that to properly describe the shape of the measured correlation functions, one needs to go beyond the Gaussian approximation. Some studies suggest that the Levy distribution could provide a good description of the source. While there are already many experimental results, there is very little input from the phenomenology side in explanation of the observed non-Gaussian source shapes. The EPOS model is a sophisticated hybrid model where the evolution of the newly-created system is governed by Parton-Based Gribov-Regge theory. It has already proved to be successful in describing many different experimental observations for the systems characterized by baryon chemical potential close to zero, but so far the source shape has not been explored in detail. In this paper we discuss studies of the pion emitting source based on the theoretical approach of the EPOS model. |
hep-ph/9701355 | Sandra Klevansky | S.P. Klevansky, P. Rehberg, A. Ogura and J. H"ufner | Developing Transport Theory to Systematically Include Mesons And
Hadronization | Proceedings of the Hirschegg Conference, QCD Phase Transitions,
January 1997 | null | null | null | hep-ph | null | Transport theory for the Nambu--Jona-Lasinio (NJL) model is examined. The
collision term is investigated in a first approach in a coupling strength
expansion. It can be demonstrated that this leads to a form easily recognized
from the Boltzmann equation if the quasiparticle approximation is used. It is
seen that enforcing a quasiparticle approximation suppresses the three body
creation and annihilation processes that would otherwise be present. Including
mesons and hadronization consistently in a $1/N_c$ expansion is discussed
briefly. Some comments on the numerical simulation of the Vlasov equation and
the relaxation time approximation to the collision term are made.
| [
{
"created": "Thu, 23 Jan 1997 11:22:06 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Klevansky",
"S. P.",
""
],
[
"Rehberg",
"P.",
""
],
[
"Ogura",
"A.",
""
],
[
"H\"ufner",
"J.",
""
]
] | Transport theory for the Nambu--Jona-Lasinio (NJL) model is examined. The collision term is investigated in a first approach in a coupling strength expansion. It can be demonstrated that this leads to a form easily recognized from the Boltzmann equation if the quasiparticle approximation is used. It is seen that enforcing a quasiparticle approximation suppresses the three body creation and annihilation processes that would otherwise be present. Including mesons and hadronization consistently in a $1/N_c$ expansion is discussed briefly. Some comments on the numerical simulation of the Vlasov equation and the relaxation time approximation to the collision term are made. |
1012.1618 | Florian Plentinger | Davide Meloni, Florian Plentinger and Walter Winter | Perturbing exactly tri-bimaximal neutrino mixings with charged lepton
mass matrices | 13 pages, 9 figures; matches published version, changes in notation | null | 10.1016/j.physletb.2011.04.033 | SISSA 83/2010/EP | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study perturbations of exactly tri-bimaximal neutrino mixings under the
assumption that they are coming solely from the charged lepton mass matrix.
This may be plausible in scenarios where the mass generation mechanisms of
neutrinos and charged leptons/quarks have a different origin. As a working
hypothesis, we assume mass textures which may be generated by the
Froggatt-Nielsen mechanism for the charged lepton and quark sectors, which
generically leads to strong hierarchies, whereas the neutrino sector is exactly
tri-bimaximal with a mild (normal) hierarchy. We find that in this approach,
deviations from maximal atmospheric mixing can be introduced without affecting
theta_13 and theta_12, whereas a deviation of theta_13 or theta_12 from its
tri-bimaximal value will inevitably lead to a similar-sized deviation of the
other parameter. Therefore, the already very precise knowledge of theta_12
points towards small sin^2(2 theta_13) <= 0.01. The magnitude of this deviation
can be controlled by the specific form of the charged lepton texture.
| [
{
"created": "Tue, 7 Dec 2010 21:45:42 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Apr 2011 13:49:46 GMT",
"version": "v2"
}
] | 2015-05-20 | [
[
"Meloni",
"Davide",
""
],
[
"Plentinger",
"Florian",
""
],
[
"Winter",
"Walter",
""
]
] | We study perturbations of exactly tri-bimaximal neutrino mixings under the assumption that they are coming solely from the charged lepton mass matrix. This may be plausible in scenarios where the mass generation mechanisms of neutrinos and charged leptons/quarks have a different origin. As a working hypothesis, we assume mass textures which may be generated by the Froggatt-Nielsen mechanism for the charged lepton and quark sectors, which generically leads to strong hierarchies, whereas the neutrino sector is exactly tri-bimaximal with a mild (normal) hierarchy. We find that in this approach, deviations from maximal atmospheric mixing can be introduced without affecting theta_13 and theta_12, whereas a deviation of theta_13 or theta_12 from its tri-bimaximal value will inevitably lead to a similar-sized deviation of the other parameter. Therefore, the already very precise knowledge of theta_12 points towards small sin^2(2 theta_13) <= 0.01. The magnitude of this deviation can be controlled by the specific form of the charged lepton texture. |
1406.2606 | Namit Mahajan | Namit Mahajan | Charged Higgs contribution to $0\nu2\beta$ decay | 5 pages | Phys. Rev. D 90, 035015 (2014) | 10.1103/PhysRevD.90.035015 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The singly charged Higgs boson contribution to $0\nu2\beta$ is neglected on
grounds of couplings involving small masses and small nuclear matrix elements.
We reconsider such contributions, but now in the light of QCD corrections and
renormalization group evolution. It is found that the charged Higgs
contribution is generically as large as (and at times significantly larger
than) the other contributions and there can be large cancellations between
contributions coming from different sources. This observation will have an
important impact on the phenomenology.
| [
{
"created": "Tue, 10 Jun 2014 16:01:44 GMT",
"version": "v1"
}
] | 2014-08-20 | [
[
"Mahajan",
"Namit",
""
]
] | The singly charged Higgs boson contribution to $0\nu2\beta$ is neglected on grounds of couplings involving small masses and small nuclear matrix elements. We reconsider such contributions, but now in the light of QCD corrections and renormalization group evolution. It is found that the charged Higgs contribution is generically as large as (and at times significantly larger than) the other contributions and there can be large cancellations between contributions coming from different sources. This observation will have an important impact on the phenomenology. |
hep-ph/0005252 | Yukinari Sumino | Y. Sumino | Gauge dependence and matching procedure of a nonrelativistic QCD
boundstate formalism | 5 pages, no figure | null | null | TU-591 | hep-ph | null | We investigate gauge dependence of a nonrelativistic boundstate formalism
used in contemporary calculations. It is known that the effective Hamiltonian
of the boundstate system depends on the choice of gauge. We obtain the gauge
transformation charge of the Hamiltonian, by which gauge independence of the
mass spectrum and gauge dependences of the boundstate wave functions are
dictated. We raise two questions of practical and physical interest, and
provide answers to them.
| [
{
"created": "Thu, 25 May 2000 10:34:33 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Sumino",
"Y.",
""
]
] | We investigate gauge dependence of a nonrelativistic boundstate formalism used in contemporary calculations. It is known that the effective Hamiltonian of the boundstate system depends on the choice of gauge. We obtain the gauge transformation charge of the Hamiltonian, by which gauge independence of the mass spectrum and gauge dependences of the boundstate wave functions are dictated. We raise two questions of practical and physical interest, and provide answers to them. |
0901.4688 | Karol Kampf | Karol Kampf, Bachir Moussallam | Chiral expansions of the pi0 lifetime | 20 pages, 1 figure; v2: comments and references added, accepted for
publication in PRD | Phys.Rev.D79:076005,2009 | 10.1103/PhysRevD.79.076005 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The corrections induced by light quark masses to the current algebra result
for the $\pi^0$ lifetime are reexamined. We consider NNLO corrections and we
compute all the one-loop and the two-loop diagrams which contribute to the
decay amplitude at NNLO in the two-flavour chiral expansion. We show that the
result is renormalizable, as Weinberg consistency conditions are satisfied. We
find that chiral logarithms are present at this order unlike the case at NLO.
The result could be used in conjunction with lattice QCD simulations, the
feasibility of which was recently demonstrated. We discuss the matching between
the two-flavour and the three-flavour chiral expansions in the anomalous sector
at order one-loop and derive the relations between the coupling constants. A
modified chiral counting is proposed, in which $m_s$ counts as $O(p)$. We have
updated the various inputs needed and used this to make a phenomenological
prediction.
| [
{
"created": "Thu, 29 Jan 2009 14:31:06 GMT",
"version": "v1"
},
{
"created": "Tue, 5 May 2009 08:45:35 GMT",
"version": "v2"
}
] | 2010-01-05 | [
[
"Kampf",
"Karol",
""
],
[
"Moussallam",
"Bachir",
""
]
] | The corrections induced by light quark masses to the current algebra result for the $\pi^0$ lifetime are reexamined. We consider NNLO corrections and we compute all the one-loop and the two-loop diagrams which contribute to the decay amplitude at NNLO in the two-flavour chiral expansion. We show that the result is renormalizable, as Weinberg consistency conditions are satisfied. We find that chiral logarithms are present at this order unlike the case at NLO. The result could be used in conjunction with lattice QCD simulations, the feasibility of which was recently demonstrated. We discuss the matching between the two-flavour and the three-flavour chiral expansions in the anomalous sector at order one-loop and derive the relations between the coupling constants. A modified chiral counting is proposed, in which $m_s$ counts as $O(p)$. We have updated the various inputs needed and used this to make a phenomenological prediction. |
1605.08077 | Dmitry Gorbunov | D. Gorbunov and A. Mitrofanov | $K^{+}\rightarrow \mu^{+}\nu_{\mu} \nu \bar \nu$ and $K^{+}\rightarrow
e^{+}\nu_{e} \nu \bar \nu$ decays within the Chiral Perturbation Theory | 10 pages, 4 figures; v2: Introduction and Conclusion extended,
journal version | null | 10.1007/JHEP10(2016)039 | INR-TH-2016-017 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Decays $K^{+} \rightarrow \mu^{+}\nu_{\mu} \nu \bar \nu$ and
$K^{+}\rightarrow e^{+}\nu_{e} \nu \bar \nu$ are examined to the leading order
in momenta in the framework of Chiral Perturbation Theory. Predictions of the
Standard Model for the muon and electron differential energy spectra and
branching ratios of $K_{\mu 3 \nu}$ and $K_{e 3 \nu}$ are presented.
| [
{
"created": "Wed, 25 May 2016 21:13:26 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Oct 2016 08:40:26 GMT",
"version": "v2"
}
] | 2016-11-03 | [
[
"Gorbunov",
"D.",
""
],
[
"Mitrofanov",
"A.",
""
]
] | Decays $K^{+} \rightarrow \mu^{+}\nu_{\mu} \nu \bar \nu$ and $K^{+}\rightarrow e^{+}\nu_{e} \nu \bar \nu$ are examined to the leading order in momenta in the framework of Chiral Perturbation Theory. Predictions of the Standard Model for the muon and electron differential energy spectra and branching ratios of $K_{\mu 3 \nu}$ and $K_{e 3 \nu}$ are presented. |
1801.04256 | Wolfgang Hollik | W. G. Hollik | Higgs Inflation at the LC | 18 pages, 6 figures. Talk presented at the International Workshop on
Future Linear Colliders (LCWS2017), Strasbourg, France, 23-27 October 2017.
C17-10-23.2; v2: typo corrected, reference added | null | null | DESY 18-005 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Most cosmological models of inflation are far away from providing a smoking
gun at low energies. A model of Higgs inflation in the Next-to-Minimal
Supersymmetric Standard Model, however, changes the NMSSM phenomenology
drastically and may be well distinguished from the pure NMSSM or MSSM at a
future Linear Collider. We point out certain differences of the inflationary
model to the ordinary NMSSM and discuss the Higgs and neutralino/chargino
sector in particular to identify the smoking gun of inflation at electroweak
energies.
| [
{
"created": "Fri, 12 Jan 2018 18:10:48 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Jan 2018 14:02:19 GMT",
"version": "v2"
}
] | 2018-01-31 | [
[
"Hollik",
"W. G.",
""
]
] | Most cosmological models of inflation are far away from providing a smoking gun at low energies. A model of Higgs inflation in the Next-to-Minimal Supersymmetric Standard Model, however, changes the NMSSM phenomenology drastically and may be well distinguished from the pure NMSSM or MSSM at a future Linear Collider. We point out certain differences of the inflationary model to the ordinary NMSSM and discuss the Higgs and neutralino/chargino sector in particular to identify the smoking gun of inflation at electroweak energies. |
hep-ph/0002049 | Uma Mahanta | Uma Mahanta and Subhendu Rakshit | Some low energy effects of a light stabilized radion in the
Randall-Sundrum model | Plain Tex, 9 pages, No figures. The text has been revised and the
effects of higgs-radion mixing induced by top quark loop on WWh and ZZh
coupling has been added | Phys.Lett.B480:176-180,2000 | 10.1016/S0370-2693(00)00352-X | null | hep-ph | null | In this paper we study some low energy effects of a light stabilized radion
in the Randall-Sundrum scenario. We find that the NLC 500 with its projected
precision level will be able to probe the radion contribution to the anomalous
magnetic moment and electric quadrupole moment of W boson for values of radion
vev up to 500 Gev. On the other hand the BNL experiment E821 will be able to
test the radion contribution to $a_{\mu}$ for 1 Tev radion vev and $m_{\phi}\le
m_{\mu}$. We have also shown that the higgs-radion mixing induces a 2.6%
correction in the WWh coupling. Finally by comparing the radionstrahlung with
the higgsstrahlung process we have found that the LEPI bound on the higgs mass
based on $Z\to hl\bar{l}$ decay mode suggests a lower bound of about 35 Gev on
the radion mass.
| [
{
"created": "Fri, 4 Feb 2000 10:30:10 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Feb 2000 14:37:27 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Mahanta",
"Uma",
""
],
[
"Rakshit",
"Subhendu",
""
]
] | In this paper we study some low energy effects of a light stabilized radion in the Randall-Sundrum scenario. We find that the NLC 500 with its projected precision level will be able to probe the radion contribution to the anomalous magnetic moment and electric quadrupole moment of W boson for values of radion vev up to 500 Gev. On the other hand the BNL experiment E821 will be able to test the radion contribution to $a_{\mu}$ for 1 Tev radion vev and $m_{\phi}\le m_{\mu}$. We have also shown that the higgs-radion mixing induces a 2.6% correction in the WWh coupling. Finally by comparing the radionstrahlung with the higgsstrahlung process we have found that the LEPI bound on the higgs mass based on $Z\to hl\bar{l}$ decay mode suggests a lower bound of about 35 Gev on the radion mass. |
hep-ph/9911327 | Kin-ya Oda | Ryuichiro Kitano and Kin-ya Oda | Neutrino Masses in the Supersymmetric Standard Model with Right-Handed
Neutrinos and Spontaneous R-Parity Violation | 22pages, RevTeX, 3 ps figures; a reference added | Phys.Rev. D61 (2000) 113001 | 10.1103/PhysRevD.61.113001 | KEK preprint 99-137, KEK-TH-661, OU-HET-331 | hep-ph | null | We propose an extension of the supersymmetric standard model with
right-handed neutrinos and a singlet Higgs field, and study the neutrino masses
in this model. The Majorana masses for the right-handed neutrinos are generated
around the supersymmetry breaking scale through the vacuum expectation value of
the singlet Higgs field. This model may induce spontaneous R-parity violation
via the vacuum expectation value of the right-handed sneutrino. In the case,
the effective theory is similar to a bilinear R-parity violating model. There
are two sources for the neutrino masses: one is this bilinear R-parity breaking
effect, and the other is the ordinary seesaw effect between left- and
right-handed neutrinos. Combining these two effects, the hierarchical neutrino
mass pattern arises even when the neutrino Yukawa matrices are not
hierarchical. We acquire appropriate masses and mixings to explain both the
solar and atmospheric neutrino oscillations.
| [
{
"created": "Fri, 12 Nov 1999 09:46:04 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Nov 1999 10:45:49 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kitano",
"Ryuichiro",
""
],
[
"Oda",
"Kin-ya",
""
]
] | We propose an extension of the supersymmetric standard model with right-handed neutrinos and a singlet Higgs field, and study the neutrino masses in this model. The Majorana masses for the right-handed neutrinos are generated around the supersymmetry breaking scale through the vacuum expectation value of the singlet Higgs field. This model may induce spontaneous R-parity violation via the vacuum expectation value of the right-handed sneutrino. In the case, the effective theory is similar to a bilinear R-parity violating model. There are two sources for the neutrino masses: one is this bilinear R-parity breaking effect, and the other is the ordinary seesaw effect between left- and right-handed neutrinos. Combining these two effects, the hierarchical neutrino mass pattern arises even when the neutrino Yukawa matrices are not hierarchical. We acquire appropriate masses and mixings to explain both the solar and atmospheric neutrino oscillations. |
hep-ph/9707281 | Goran Senjanovic | Rabindra N. Mohapatra, Andrija Rasin, Goran Senjanovic | P, C and Strong CP in Left-Right Supersymmetric Models | 5 pages, RevTex, no figures. Some minor changes, final version as
published in Phys. Rev. Lett. 79, 4744 (1997) | Phys.Rev.Lett. 79 (1997) 4744-4747 | 10.1103/PhysRevLett.79.4744 | UMD-PP-97-118 | hep-ph | null | We systematically study the connection between P, C and strong CP in the
context of both non-supersymmetric and supersymmetric left-right theories. We
find that the solution to the strong CP problem requires both supersymmetry and
parity breaking scales to be around the weak scale.
| [
{
"created": "Tue, 8 Jul 1997 18:36:31 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Dec 1997 21:57:29 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Mohapatra",
"Rabindra N.",
""
],
[
"Rasin",
"Andrija",
""
],
[
"Senjanovic",
"Goran",
""
]
] | We systematically study the connection between P, C and strong CP in the context of both non-supersymmetric and supersymmetric left-right theories. We find that the solution to the strong CP problem requires both supersymmetry and parity breaking scales to be around the weak scale. |
hep-ph/0502239 | Bodo Geyer | Bodo Geyer and Oliver Witzel | B-Meson Distribution Amplitudes of Geometric Twist vs. Dynamical Twist | 18 pages, Latex 2e, no figures | Phys.Rev. D72 (2005) 034023 | 10.1103/PhysRevD.72.034023 | null | hep-ph | null | Two- and three-particle distribution amplitudes of heavy pseudoscalar mesons
of well-defined geometric twist are introduced. They are obtained from
appropriately parametrized vacuum-to-meson matrix elements by applying those
twist projectors which determine the enclosed light-cone operators of definite
geometric twist and, in addition, observing the heavy quark constraint.
Comparing these distribution amplitudes with the conventional ones of dynamical
twist we derive relations between them, partially being of Wandzura-Wilczek
type; also sum rules of Burkhardt-Cottingham type are derived.The derivation is
performed for the (double) Mellin moments and then re-summed to the non-local
distribution amplitudes. Furthermore, a parametrization of vacuum-to-meson
matrix elements for non-local operators off the light-cone in terms of
distribution amplitudes accompanying independent kinematical structures is
derived.
| [
{
"created": "Sun, 27 Feb 2005 15:30:08 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Geyer",
"Bodo",
""
],
[
"Witzel",
"Oliver",
""
]
] | Two- and three-particle distribution amplitudes of heavy pseudoscalar mesons of well-defined geometric twist are introduced. They are obtained from appropriately parametrized vacuum-to-meson matrix elements by applying those twist projectors which determine the enclosed light-cone operators of definite geometric twist and, in addition, observing the heavy quark constraint. Comparing these distribution amplitudes with the conventional ones of dynamical twist we derive relations between them, partially being of Wandzura-Wilczek type; also sum rules of Burkhardt-Cottingham type are derived.The derivation is performed for the (double) Mellin moments and then re-summed to the non-local distribution amplitudes. Furthermore, a parametrization of vacuum-to-meson matrix elements for non-local operators off the light-cone in terms of distribution amplitudes accompanying independent kinematical structures is derived. |
1809.06881 | Juan Herrero-Garcia | Juan Herrero-Garcia, Andre Scaffidi, Martin White and Anthony G.
Williams | On the direct detection of multi-component dark matter: implications of
the relic abundance | 22 pages, 11 figures, 1 table. Minor changes, matches published
version in JCAP | null | 10.1088/1475-7516/2019/01/008 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently we studied the direct detection of multi-component dark matter with
arbitrary local energy densities. Although the generation of the dark matter
relic abundance is model-dependent, and in principle could be only indirectly
related to direct detection, it is interesting to consider the implications of
the former on the latter. In this work we conduct an extended analysis to
include constraints from two natural scenarios of dark matter genesis:
asymmetric dark matter and thermal freeze-out. In the first (second) case, the
dark matter number (energy) densities of the different components are expected
to be similar. In the case of thermal freeze-out, we assume that the global
energy density scales with the local one. In our numerical analysis we analyse
the median sensitivity of direct detection experiments to discriminate a
two-component scenario from a one-component one, and also the precision with
which dark matter parameters can be extracted. We analyse these generic
scenarios for both light and heavy mediators. We find that most scenarios have
a relatively suppressed maximum median sensitivity compared to the previously
studied general cases. We also find that the asymmetric scenario is more
promising than the thermal freeze-out one.
| [
{
"created": "Tue, 18 Sep 2018 18:29:16 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Jan 2019 10:13:58 GMT",
"version": "v2"
}
] | 2019-01-23 | [
[
"Herrero-Garcia",
"Juan",
""
],
[
"Scaffidi",
"Andre",
""
],
[
"White",
"Martin",
""
],
[
"Williams",
"Anthony G.",
""
]
] | Recently we studied the direct detection of multi-component dark matter with arbitrary local energy densities. Although the generation of the dark matter relic abundance is model-dependent, and in principle could be only indirectly related to direct detection, it is interesting to consider the implications of the former on the latter. In this work we conduct an extended analysis to include constraints from two natural scenarios of dark matter genesis: asymmetric dark matter and thermal freeze-out. In the first (second) case, the dark matter number (energy) densities of the different components are expected to be similar. In the case of thermal freeze-out, we assume that the global energy density scales with the local one. In our numerical analysis we analyse the median sensitivity of direct detection experiments to discriminate a two-component scenario from a one-component one, and also the precision with which dark matter parameters can be extracted. We analyse these generic scenarios for both light and heavy mediators. We find that most scenarios have a relatively suppressed maximum median sensitivity compared to the previously studied general cases. We also find that the asymmetric scenario is more promising than the thermal freeze-out one. |
1305.1016 | Tirtha Sankar Ray | Ujjal Kumar Dey, Tirtha Sankar Ray | Constraining minimal and non-minimal UED models with Higgs couplings | KK level mixing effects included, resembles published version, 8
pages, 4 figures | Phys. Rev. D 88, 056016 (2013) | 10.1103/PhysRevD.88.056016 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Early indications from the LHC for the observed scalar boson imply properties
close to the Standard Model Higgs, putting considerable constraints on TeV
scale new physics scenarios. In this letter we consider flat extra dimensional
scenarios with the fifth spatial dimension compactified on an S^1/Z_2 orbifold.
We find in the minimal model the experimentally preferred effective Higgs
couplings to gluon and photon at 95% confidence level disfavor the New Physics
scale below 1.3 TeV. We demonstrate that a generalization of these models to
include brane localized kinetic terms can relieve the tension to accommodate
scales as low as 0.4 TeV.
| [
{
"created": "Sun, 5 May 2013 14:39:46 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Jun 2013 12:44:46 GMT",
"version": "v2"
},
{
"created": "Fri, 20 Sep 2013 06:23:48 GMT",
"version": "v3"
}
] | 2013-09-23 | [
[
"Dey",
"Ujjal Kumar",
""
],
[
"Ray",
"Tirtha Sankar",
""
]
] | Early indications from the LHC for the observed scalar boson imply properties close to the Standard Model Higgs, putting considerable constraints on TeV scale new physics scenarios. In this letter we consider flat extra dimensional scenarios with the fifth spatial dimension compactified on an S^1/Z_2 orbifold. We find in the minimal model the experimentally preferred effective Higgs couplings to gluon and photon at 95% confidence level disfavor the New Physics scale below 1.3 TeV. We demonstrate that a generalization of these models to include brane localized kinetic terms can relieve the tension to accommodate scales as low as 0.4 TeV. |
1701.04340 | Victor Goncalves | V. P. Goncalves, F. S. Navarra, D. Spiering | Investigating the impact of the gluon saturation effects on the momentum
transfer distributions for the exclusive vector meson photoproduction in
hadronic collisions | 7 pages, 5 figures. arXiv admin note: text overlap with
arXiv:1612.06254 | null | 10.1016/j.physletb.2017.03.009 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The exclusive vector meson production cross section is one of the most
promising observables to probe the high energy regime of the QCD dynamics. In
particular, the squared momentum transfer ($t$) distributions are an important
source of information about the spatial distribution of the gluons in the
hadron and about fluctuations of the color fields. In this paper we complement
previous studies on exclusive vector meson photoproduction in hadronic
collisions presenting a comprehensive analysis of the $t$ - spectrum measured
in exclusive $\rho$, $\phi$ and $J/\Psi$ photoproduction in $pp$ and $PbPb$
collisions at the LHC. We compute the differential cross sections taking into
account gluon saturation effects and compare the predictions with those
obtained in the linear regime of the QCD dynamics. Our results show that gluon
saturation suppresses the magnitude of the cross sections and shifts the
position of the dips towards smaller values of $t$.
| [
{
"created": "Mon, 16 Jan 2017 15:57:36 GMT",
"version": "v1"
}
] | 2017-04-05 | [
[
"Goncalves",
"V. P.",
""
],
[
"Navarra",
"F. S.",
""
],
[
"Spiering",
"D.",
""
]
] | The exclusive vector meson production cross section is one of the most promising observables to probe the high energy regime of the QCD dynamics. In particular, the squared momentum transfer ($t$) distributions are an important source of information about the spatial distribution of the gluons in the hadron and about fluctuations of the color fields. In this paper we complement previous studies on exclusive vector meson photoproduction in hadronic collisions presenting a comprehensive analysis of the $t$ - spectrum measured in exclusive $\rho$, $\phi$ and $J/\Psi$ photoproduction in $pp$ and $PbPb$ collisions at the LHC. We compute the differential cross sections taking into account gluon saturation effects and compare the predictions with those obtained in the linear regime of the QCD dynamics. Our results show that gluon saturation suppresses the magnitude of the cross sections and shifts the position of the dips towards smaller values of $t$. |
1206.6063 | George W. S. Hou | Yukihiro Mimura, Wei-Shu Hou, Hiroaki Kohyama | Bootstrap Dynamical Symmetry Breaking with New Heavy Chiral Quarks | updated with ICHEP and HCP 2012 results on discovery of Higgs-like
particle, version still under review at JHEP (figures unchanged) | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A Higgs-like new boson with mass around 126 GeV is now established, but its
true nature probably cannot be settled with 2011--2012 LHC data. We assume it
is a dilaton with couplings weaker than the Higgs boson (except to
$\gamma\gamma$ and $gg$), and explore dynamical symmetry breaking (DSB) by
strong Yukawa coupling of a yet unseen heavy chiral quark doublet $Q$. Assuming
the actual Higgs boson to be heavy, the Goldstone boson $G$ of electroweak
symmetry breaking still couples to $Q$ with Yukawa coupling $\lambda_Q$. A
``bootstrap" gap equation without a Higgs particle is constructed. Electroweak
symmetry breaking via strong $\lambda_Q$ generates both heavy mass for $Q$,
while self-consistently justifying $G$ as a massless Goldstone particle in the
loop. The spontaneous breaking of scale invariance in principle \emph{allows}
for a dilaton. We numerically solve such a gap equation and find the mass of
the heavy quark to be a couple of TeV. We offer a short critique on the results
of the scale-invariant model of Hung and Xiong, where a similar gap equation is
built with a massless scalar doublet. Through this we show that a light SM
Higgs at 126 GeV cannot be viable within our approach to DSB, while a dilaton
with weaker couplings is consistent with our main result.
| [
{
"created": "Tue, 26 Jun 2012 17:41:34 GMT",
"version": "v1"
},
{
"created": "Thu, 31 Jan 2013 16:17:59 GMT",
"version": "v2"
}
] | 2013-02-01 | [
[
"Mimura",
"Yukihiro",
""
],
[
"Hou",
"Wei-Shu",
""
],
[
"Kohyama",
"Hiroaki",
""
]
] | A Higgs-like new boson with mass around 126 GeV is now established, but its true nature probably cannot be settled with 2011--2012 LHC data. We assume it is a dilaton with couplings weaker than the Higgs boson (except to $\gamma\gamma$ and $gg$), and explore dynamical symmetry breaking (DSB) by strong Yukawa coupling of a yet unseen heavy chiral quark doublet $Q$. Assuming the actual Higgs boson to be heavy, the Goldstone boson $G$ of electroweak symmetry breaking still couples to $Q$ with Yukawa coupling $\lambda_Q$. A ``bootstrap" gap equation without a Higgs particle is constructed. Electroweak symmetry breaking via strong $\lambda_Q$ generates both heavy mass for $Q$, while self-consistently justifying $G$ as a massless Goldstone particle in the loop. The spontaneous breaking of scale invariance in principle \emph{allows} for a dilaton. We numerically solve such a gap equation and find the mass of the heavy quark to be a couple of TeV. We offer a short critique on the results of the scale-invariant model of Hung and Xiong, where a similar gap equation is built with a massless scalar doublet. Through this we show that a light SM Higgs at 126 GeV cannot be viable within our approach to DSB, while a dilaton with weaker couplings is consistent with our main result. |
1805.01549 | M\'aximo Coppola | M. Coppola, D. Gomez Dumm, N.N. Scoccola | Pion masses under intense magnetic fields within the NJL model | Poster presented at the XIV International Workshop on Hadron Physics,
Florian\'opolis, Brazil, March 2018 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The behavior of charged and neutral pion masses in the presence of a static
uniform magnetic field is studied in the framework of the two-flavor
Nambu-Jona-Lasinio (NJL) model. Analytical calculations are carried out
employing the Ritus eigenfunction method. Numerical results are obtained for
definite model parameters, comparing the predictions of the model with present
lattice QCD (LQCD) results.
| [
{
"created": "Thu, 3 May 2018 21:36:53 GMT",
"version": "v1"
}
] | 2018-05-07 | [
[
"Coppola",
"M.",
""
],
[
"Dumm",
"D. Gomez",
""
],
[
"Scoccola",
"N. N.",
""
]
] | The behavior of charged and neutral pion masses in the presence of a static uniform magnetic field is studied in the framework of the two-flavor Nambu-Jona-Lasinio (NJL) model. Analytical calculations are carried out employing the Ritus eigenfunction method. Numerical results are obtained for definite model parameters, comparing the predictions of the model with present lattice QCD (LQCD) results. |
1607.00011 | Carlos Arguelles Delgado | G.H. Collin and C.A. Arg\"uelles and J.M. Conrad and M.H. Shaevitz | First Constraints on the Complete Neutrino Mixing Matrix with a Sterile
Neutrino | 7 pages, 4 figures | Phys. Rev. Lett. 117, 221801 (2016) | 10.1103/PhysRevLett.117.221801 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Neutrino oscillation models involving one extra mass eigenstate beyond the
standard three ($3+1$) are fit to global short baseline experimental data and
the recent IceCube $\nu_\mu+\bar\nu_\mu$ disappearance search result. We find a
best fit of $\Delta m^2_{41} = 1.75\; \text{eV}^2$ with $\Delta
\chi^2_{null-min}$ (dof) of 50.61 (4). We find that the combined IceCube and
short baseline data constrain $\theta_{34}$ to $< 80^\circ (< 6^\circ) $ at
90\% C.L. for $\Delta m^2_{41} \approx 2 (6)~\text{eV}^2$, which is improved
over present limits. Incorporating the IceCube information provides the first
constraints on all entries of the 3+1 mixing matrix.
| [
{
"created": "Thu, 30 Jun 2016 20:00:06 GMT",
"version": "v1"
},
{
"created": "Tue, 12 Jul 2016 20:12:08 GMT",
"version": "v2"
},
{
"created": "Tue, 25 Oct 2016 19:55:53 GMT",
"version": "v3"
}
] | 2016-11-30 | [
[
"Collin",
"G. H.",
""
],
[
"Argüelles",
"C. A.",
""
],
[
"Conrad",
"J. M.",
""
],
[
"Shaevitz",
"M. H.",
""
]
] | Neutrino oscillation models involving one extra mass eigenstate beyond the standard three ($3+1$) are fit to global short baseline experimental data and the recent IceCube $\nu_\mu+\bar\nu_\mu$ disappearance search result. We find a best fit of $\Delta m^2_{41} = 1.75\; \text{eV}^2$ with $\Delta \chi^2_{null-min}$ (dof) of 50.61 (4). We find that the combined IceCube and short baseline data constrain $\theta_{34}$ to $< 80^\circ (< 6^\circ) $ at 90\% C.L. for $\Delta m^2_{41} \approx 2 (6)~\text{eV}^2$, which is improved over present limits. Incorporating the IceCube information provides the first constraints on all entries of the 3+1 mixing matrix. |
1207.5795 | Maximilian Attems | Maximilian Attems, Anton Rebhan, Michael Strickland | Instabilities of an anisotropically expanding non-Abelian plasma: 3D+3V
discretized hard-loop simulations | 25 pages, 13 figures; v3: corrected labels of fig. 11, minor
additions, version accepted to PRD | Phys. Rev. D 87, 025010 (2013) | 10.1103/PhysRevD.87.025010 | TUW-12-16 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the (3+1)-dimensional evolution of non-Abelian plasma instabilities
in the presence of a longitudinally expanding background of hard particles
using the discretized hard loop framework. The free streaming background
dynamically generates a momentum-space anisotropic distribution which is
unstable to the rapid growth of chromomagnetic and chromoelectric fields. These
fields produce longitudinal pressure that works to isotropize the system.
Extrapolating our results to energies probed in ultrarelativistic heavy-ion
collisions we find, however, that a pressure anisotropy persists for a few
fm/c. In addition, on time scales relevant to heavy-ion collisions we observe
continued growth of plasma instabilities in the strongly non-Abelian regime.
Finally, we find that the longitudinal energy spectrum is well-described by a
Boltzmann distribution with increasing temperature at intermediate time scales.
| [
{
"created": "Tue, 24 Jul 2012 20:00:02 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Sep 2012 13:36:48 GMT",
"version": "v2"
},
{
"created": "Wed, 19 Dec 2012 14:59:46 GMT",
"version": "v3"
}
] | 2013-01-15 | [
[
"Attems",
"Maximilian",
""
],
[
"Rebhan",
"Anton",
""
],
[
"Strickland",
"Michael",
""
]
] | We study the (3+1)-dimensional evolution of non-Abelian plasma instabilities in the presence of a longitudinally expanding background of hard particles using the discretized hard loop framework. The free streaming background dynamically generates a momentum-space anisotropic distribution which is unstable to the rapid growth of chromomagnetic and chromoelectric fields. These fields produce longitudinal pressure that works to isotropize the system. Extrapolating our results to energies probed in ultrarelativistic heavy-ion collisions we find, however, that a pressure anisotropy persists for a few fm/c. In addition, on time scales relevant to heavy-ion collisions we observe continued growth of plasma instabilities in the strongly non-Abelian regime. Finally, we find that the longitudinal energy spectrum is well-described by a Boltzmann distribution with increasing temperature at intermediate time scales. |
1306.6022 | Jan L\"ucker | Christian S. Fischer, Leonard Fister, Jan Luecker, Jan M. Pawlowski | Polyakov loop potential at finite density | 5 pages, 9 figures | null | 10.1016/j.physletb.2014.03.057 | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Polyakov loop potential serves to distinguish between the confined
hadronic and the deconfined quark-gluon plasma phases of QCD. For Nf=2+1 quark
flavors with physical masses we determine the Polyakov loop potential at finite
temperature and density and extract the location of the deconfinement
transition. We find a cross-over at small values of the chemical potential
running into a critical end-point at mu/T > 1.
| [
{
"created": "Tue, 25 Jun 2013 16:31:41 GMT",
"version": "v1"
}
] | 2015-06-16 | [
[
"Fischer",
"Christian S.",
""
],
[
"Fister",
"Leonard",
""
],
[
"Luecker",
"Jan",
""
],
[
"Pawlowski",
"Jan M.",
""
]
] | The Polyakov loop potential serves to distinguish between the confined hadronic and the deconfined quark-gluon plasma phases of QCD. For Nf=2+1 quark flavors with physical masses we determine the Polyakov loop potential at finite temperature and density and extract the location of the deconfinement transition. We find a cross-over at small values of the chemical potential running into a critical end-point at mu/T > 1. |
hep-ph/9407257 | null | J. Rosner (University of Chicago) | Our Present Understanding of CP Violation | 26 Pages, LaTeX, 7 figures not included (available in hard copy upon
request). July, 1994, Enrico Fermi Institute report EFI 94-25 | null | null | null | hep-ph | null | If CP violation in the decays of neutral kaons is due to phases in the weak
couplings of quarks, as encoded in the Cabibbo-Kobayashi-Maskawa (CKM) matrix,
there are many other experimental consequences. Notable among these are
CP-violating rate asymmetries and triangle relations among decay rates in $B$
meson decays, while charmed particle decays should not be a good place to see
CP-violating effects. In the context of the CKM and other models of CP
violation, we discuss phenomena such as electric dipole moments, the baryon
asymmetry of the Universe, and the strong CP problem, and speculate on a common
origin for CP-violating phenomena.
| [
{
"created": "Thu, 7 Jul 1994 16:02:30 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Rosner",
"J.",
"",
"University of Chicago"
]
] | If CP violation in the decays of neutral kaons is due to phases in the weak couplings of quarks, as encoded in the Cabibbo-Kobayashi-Maskawa (CKM) matrix, there are many other experimental consequences. Notable among these are CP-violating rate asymmetries and triangle relations among decay rates in $B$ meson decays, while charmed particle decays should not be a good place to see CP-violating effects. In the context of the CKM and other models of CP violation, we discuss phenomena such as electric dipole moments, the baryon asymmetry of the Universe, and the strong CP problem, and speculate on a common origin for CP-violating phenomena. |
hep-ph/0107323 | Vento Vicente | Vicente Vento (Universidad de Valencia, Spain) | Quark degrees of freedom in hadronic systems: Partonic distributions | 12 pages, 3 figures, to appear in the Proceedings of the 8th
Conference Mesons and Light Nuclei, Prague '01. Requires AIP Press macros | AIP Conf.Proc.603:199-210,2001 | 10.1063/1.1436601 | FTUV-01-0718 and IFIC/01-40 | hep-ph | null | The role of models in Quantum Chromodynamics is to produce simple physical
pictures that connect the phenomenological regularities with the underlying
structure. The static properties of hadrons have provided experimental input to
define a variety of very succesful Quark Models. We discuss applications of
some of the most widely used of these models to the high energy regime, a
scenario for which they were not proposed. The initial assumption underlying
our presentation will be that gluon and sea bremsstrahlung connect the
constituent quark momentum distributions with the partonic structure functions.
The results obtained are encouraging but lead to the necessity of more complex
structures at the hadronic scale. This initial hypothesis may be relaxed by
introducing some non perturbative model for the constituent quarks. Within this
scheme we will discuss some relevant problems in nucleon structure as seen in
high energy experiments.
| [
{
"created": "Tue, 31 Jul 2001 15:06:45 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Vento",
"Vicente",
"",
"Universidad de Valencia, Spain"
]
] | The role of models in Quantum Chromodynamics is to produce simple physical pictures that connect the phenomenological regularities with the underlying structure. The static properties of hadrons have provided experimental input to define a variety of very succesful Quark Models. We discuss applications of some of the most widely used of these models to the high energy regime, a scenario for which they were not proposed. The initial assumption underlying our presentation will be that gluon and sea bremsstrahlung connect the constituent quark momentum distributions with the partonic structure functions. The results obtained are encouraging but lead to the necessity of more complex structures at the hadronic scale. This initial hypothesis may be relaxed by introducing some non perturbative model for the constituent quarks. Within this scheme we will discuss some relevant problems in nucleon structure as seen in high energy experiments. |
2112.12649 | Terry Generet | Terry Generet | Top-pair events with B-hadrons at the LHC | 5 pages, 6 figures. Talk at the 14th International Workshop on Top
Quark Physics (videoconference), 13-17 September 2021 | null | null | TTK-21-59 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In these proceedings, we summarise the results of the recent calculation of
the NNLO QCD corrections for the production of a top-quark pair in association
with a bottom-flavoured hadron. The results consist of differential
distributions of observables involving the identified hadron.
| [
{
"created": "Thu, 23 Dec 2021 15:37:54 GMT",
"version": "v1"
}
] | 2021-12-24 | [
[
"Generet",
"Terry",
""
]
] | In these proceedings, we summarise the results of the recent calculation of the NNLO QCD corrections for the production of a top-quark pair in association with a bottom-flavoured hadron. The results consist of differential distributions of observables involving the identified hadron. |
hep-ph/9703336 | null | Hitoshi Yamamoto (Harvard University) | Lepton CP Asymmetries in B Decays | 13 pages, no figures, Latex. References updated | Phys.Lett. B401 (1997) 91-99 | 10.1016/S0370-2693(97)00388-2 | HUTP-97/A011 | hep-ph | null | In the decay of Upsilon(4S, the decay time distribution of Upsilon(4S) -> f +
X, where f is a final state that B^0 or B^0bar can decay to, is the sum of the
decay time distributions of B^0 -> f and B^0bar -> f. Using this general rule,
we estimate the sensitivity of single lepton CP violation measurements with
respect to that of traditional di-lepton measurements. We find that the
sensitivity of the single lepton method is comparable to or better than that of
the di-lepton method. The two data samples are largely statistically
independent, so that they can be combined to improve sensitivity. The advantage
of the single lepton measurement increases for large mixings, which suggests
that the single lepton method holds promise for B_s. We also discuss lepton
asymmetry measurements on the Z^0 peak and in hadron colliders. The achievable
sensitivity with the currently available data is already in the range relevant
to standard model predictions. PACS numbers: 11.30.Er, 13.20.Gd, 13.20.He,
03.65.Bx
| [
{
"created": "Sun, 16 Mar 1997 23:14:12 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Mar 1997 07:11:53 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Yamamoto",
"Hitoshi",
"",
"Harvard University"
]
] | In the decay of Upsilon(4S, the decay time distribution of Upsilon(4S) -> f + X, where f is a final state that B^0 or B^0bar can decay to, is the sum of the decay time distributions of B^0 -> f and B^0bar -> f. Using this general rule, we estimate the sensitivity of single lepton CP violation measurements with respect to that of traditional di-lepton measurements. We find that the sensitivity of the single lepton method is comparable to or better than that of the di-lepton method. The two data samples are largely statistically independent, so that they can be combined to improve sensitivity. The advantage of the single lepton measurement increases for large mixings, which suggests that the single lepton method holds promise for B_s. We also discuss lepton asymmetry measurements on the Z^0 peak and in hadron colliders. The achievable sensitivity with the currently available data is already in the range relevant to standard model predictions. PACS numbers: 11.30.Er, 13.20.Gd, 13.20.He, 03.65.Bx |
0710.5773 | Orhan Cakir | O.Cakir (2) and K.O.Ozansoy (1, 2) ((1) University of Wisconsin,
Madison, USA, (2) Ankara University, Ankara, Turkey) | Unparticle Searches Through Compton Scattering | Table 1 and 2 have been combined as Table 1, references updated,
minor typos have been corrected | Europhys.Lett.83:51001,2008 | 10.1209/0295-5075/83/51001 | null | hep-ph | null | We investigate the effects of unparticles on Compton scattering, e gamma -> e
gamma based on a future e^+e^- linear collider such as the CLIC. For different
polarization configurations, we calculate the lower limits of the unparticle
energy scale Lambda_U for a discovery reach at the center of mass energies
sqrt(s)=0.5 TeV- 3 TeV. It is shown that, especially, for smaller values of the
mass dimension d, (1 <d <1.3), and for high energies and luminosities of the
collider these bounds are very significant. As a stringent limit, we find
Lambda_U>80 TeV for d<1.3 at sqrt(s)=3 TeV, and 1 ab^(-1) integrated luminosity
per year, which is comparable with the limits calculated from other low and
high energy physics implications.
| [
{
"created": "Wed, 31 Oct 2007 10:05:48 GMT",
"version": "v1"
},
{
"created": "Sun, 6 Jan 2008 19:55:57 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Cakir",
"O.",
""
],
[
"Ozansoy",
"K. O.",
""
]
] | We investigate the effects of unparticles on Compton scattering, e gamma -> e gamma based on a future e^+e^- linear collider such as the CLIC. For different polarization configurations, we calculate the lower limits of the unparticle energy scale Lambda_U for a discovery reach at the center of mass energies sqrt(s)=0.5 TeV- 3 TeV. It is shown that, especially, for smaller values of the mass dimension d, (1 <d <1.3), and for high energies and luminosities of the collider these bounds are very significant. As a stringent limit, we find Lambda_U>80 TeV for d<1.3 at sqrt(s)=3 TeV, and 1 ab^(-1) integrated luminosity per year, which is comparable with the limits calculated from other low and high energy physics implications. |
0802.2648 | Qiang Zhao | Xiao-Hai Liu, Qiang Zhao, and Frank E. Close | Search for tetraquark candidate Z(4430) in meson photoproduction | Minor changes with wording; Revised version to appear on Phys. Rev. D | Phys.Rev.D77:094005,2008 | 10.1103/PhysRevD.77.094005 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a search for the newly discovered tetraquark candidate Z(4430) in
photoproduction. Based on the Belle results we show that if Z(4430) is a
genuine resonance, its significantly large coupling to $\psi^\prime\pi$ will
cause it to stand out above the background in $\gamma p\to Z^+(4430) n\to
\psi^\prime \pi^+ n$. We consider the dependence of the cross section for the
quantum numbers ($J^{P}=1^{-}$, $1^{+}$ or $0^{-}$).
| [
{
"created": "Tue, 19 Feb 2008 13:05:22 GMT",
"version": "v1"
},
{
"created": "Sat, 29 Mar 2008 11:55:59 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Liu",
"Xiao-Hai",
""
],
[
"Zhao",
"Qiang",
""
],
[
"Close",
"Frank E.",
""
]
] | We propose a search for the newly discovered tetraquark candidate Z(4430) in photoproduction. Based on the Belle results we show that if Z(4430) is a genuine resonance, its significantly large coupling to $\psi^\prime\pi$ will cause it to stand out above the background in $\gamma p\to Z^+(4430) n\to \psi^\prime \pi^+ n$. We consider the dependence of the cross section for the quantum numbers ($J^{P}=1^{-}$, $1^{+}$ or $0^{-}$). |
1203.4254 | Kristjan Kannike | Pier Paolo Giardino, Kristjan Kannike, Martti Raidal and Alessandro
Strumia | Reconstructing Higgs boson properties from the LHC and Tevatron data | 15 pages, 5 figures, references added, discussion clarified (e.g. fit
to invisible width), fit to radion added | null | 10.1007/JHEP06(2012)117 | CERN-PH-TH/2012-066 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a phenomenological fit to all ATLAS, CMS, CDF and D0 Higgs boson
data available after Moriond 2012. We allow all Higgs boson branching
fractions, its couplings to standard model particles, as well as to an
hypothetical invisible sector to vary freely, and determine their current
favourite values. The standard model Higgs boson with a mass 125 GeV correctly
predicts the average observed rate and provides an acceptable global fit to
data. However, better fits are obtained by non-standard scenarios that
reproduce anomalies in the present data (more \gamma\gamma{} and less WW
signals than expected), such as modified rates of loop processes or partial
fermiophobia. We find that present data disfavours Higgs boson invisible
decays. We consider implications for the standard model, for supersymmetric and
fermiophobic Higgs bosons, for dark matter models, for warped extra-dimensions.
| [
{
"created": "Mon, 19 Mar 2012 20:45:27 GMT",
"version": "v1"
},
{
"created": "Wed, 9 May 2012 09:42:20 GMT",
"version": "v2"
}
] | 2015-06-04 | [
[
"Giardino",
"Pier Paolo",
""
],
[
"Kannike",
"Kristjan",
""
],
[
"Raidal",
"Martti",
""
],
[
"Strumia",
"Alessandro",
""
]
] | We perform a phenomenological fit to all ATLAS, CMS, CDF and D0 Higgs boson data available after Moriond 2012. We allow all Higgs boson branching fractions, its couplings to standard model particles, as well as to an hypothetical invisible sector to vary freely, and determine their current favourite values. The standard model Higgs boson with a mass 125 GeV correctly predicts the average observed rate and provides an acceptable global fit to data. However, better fits are obtained by non-standard scenarios that reproduce anomalies in the present data (more \gamma\gamma{} and less WW signals than expected), such as modified rates of loop processes or partial fermiophobia. We find that present data disfavours Higgs boson invisible decays. We consider implications for the standard model, for supersymmetric and fermiophobic Higgs bosons, for dark matter models, for warped extra-dimensions. |
hep-ph/9611416 | Matthias Burkardt | M. Burkardt (New Mexico State University) | Fermions and Condensates on the Light-Front | lecture notes, 28 pages, lamuphys.sty | null | null | null | hep-ph | null | Light-Front quantization is one of the most promising and physical tools
towards studying deep inelastic scattering on the basis of quark gluon degrees
of freedom. The simplified vacuum structure (nontrivial vacuum effects can only
appear in zero-mode degrees of freedom) and the physical basis allows for a
description of hadrons that stays close to intuition. I am reviewing recent
progress in understanding the deep connection between renormalization of
light-front Hamiltonians, effective light-front Hamiltonians and nontrivial
vacuum condensates.
| [
{
"created": "Mon, 25 Nov 1996 19:34:02 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Burkardt",
"M.",
"",
"New Mexico State University"
]
] | Light-Front quantization is one of the most promising and physical tools towards studying deep inelastic scattering on the basis of quark gluon degrees of freedom. The simplified vacuum structure (nontrivial vacuum effects can only appear in zero-mode degrees of freedom) and the physical basis allows for a description of hadrons that stays close to intuition. I am reviewing recent progress in understanding the deep connection between renormalization of light-front Hamiltonians, effective light-front Hamiltonians and nontrivial vacuum condensates. |
hep-ph/9902330 | null | Yi-Bing Ding, Xue-Qian Li, Peng-Nian Shen | Singularity in Potential, Perturbation and Variational Methods | 14 pages, Latex | Commun.Theor.Phys.33:613-620,2000 | 10.1088/0253-6102/33/4/613 | null | hep-ph | null | In this work, we carefully study the energy eigen-values and splitting of
heavy quarkonia as there exist $1/r^3$ and $\delta^3(\vec r)$ singular terms in
the potential which make a direct numerical solution of the Schr\"{o}dinger
equation impossible. We compare the results obtained in terms of perturbation
and variational methods with various treatments.
| [
{
"created": "Fri, 12 Feb 1999 08:32:39 GMT",
"version": "v1"
}
] | 2018-01-17 | [
[
"Ding",
"Yi-Bing",
""
],
[
"Li",
"Xue-Qian",
""
],
[
"Shen",
"Peng-Nian",
""
]
] | In this work, we carefully study the energy eigen-values and splitting of heavy quarkonia as there exist $1/r^3$ and $\delta^3(\vec r)$ singular terms in the potential which make a direct numerical solution of the Schr\"{o}dinger equation impossible. We compare the results obtained in terms of perturbation and variational methods with various treatments. |
1703.01682 | Muhammad Goharipour | Muhammad Goharipour and Hossein Mehraban | Predictions for the isolated prompt photon production at the LHC at $
\sqrt s= $13 TeV | 8 pages, 7 figures | Adv.High Energy Phys. 2017 (2017) 3802381 | 10.1155/2017/3802381 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The prompt photon production in hadronic collisions has a long history of
providing information on the substructure of hadrons and testing the
perturbative techniques of QCD. Some valuable information about the parton
densities in the nucleon and nuclei, especially of the gluon, can also be
achieved by analysing the measurements of the prompt photon production cross
section whether inclusively or in association with heavy quarks or jets. In
this work, we present predictions for the inclusive isolated prompt photon
production in $ pp $ collisions at center-of-mass energy of 13 TeV using
various modern PDF sets. The calculations are presented both as a function of
photon transverse energy $ E_\textrm{T}^\gamma $ and pseudorapidity $
\eta^\gamma $ for the ATLAS kinematic coverage. We also study in detail the
theoretical uncertainty in the cross sections due to the variation of the
renormalization, factorization and fragmentation scales. Moreover, we introduce
and calculate the ratios of photon momenta for different rapidity regions and
study the impact of various input PDFs on such quantity.
| [
{
"created": "Sun, 5 Mar 2017 22:45:05 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Mar 2017 15:34:40 GMT",
"version": "v2"
}
] | 2017-03-14 | [
[
"Goharipour",
"Muhammad",
""
],
[
"Mehraban",
"Hossein",
""
]
] | The prompt photon production in hadronic collisions has a long history of providing information on the substructure of hadrons and testing the perturbative techniques of QCD. Some valuable information about the parton densities in the nucleon and nuclei, especially of the gluon, can also be achieved by analysing the measurements of the prompt photon production cross section whether inclusively or in association with heavy quarks or jets. In this work, we present predictions for the inclusive isolated prompt photon production in $ pp $ collisions at center-of-mass energy of 13 TeV using various modern PDF sets. The calculations are presented both as a function of photon transverse energy $ E_\textrm{T}^\gamma $ and pseudorapidity $ \eta^\gamma $ for the ATLAS kinematic coverage. We also study in detail the theoretical uncertainty in the cross sections due to the variation of the renormalization, factorization and fragmentation scales. Moreover, we introduce and calculate the ratios of photon momenta for different rapidity regions and study the impact of various input PDFs on such quantity. |
hep-ph/0211114 | Marco Aurelio Diaz | M.A. Diaz, R.A. Lineros, and M.A. Rivera | Charged Higgs and Stau Production in Anomaly Mediated Supersymmetry
Breaking | 4 pages, including 1 figure. Presented at Workshop on Physics and
Experiments with Future Electron-Positron Linear Colliders August 26-30,
2002, Jeju Island, Korea | null | null | null | hep-ph | null | Charged Higgs production in association with staus in electron positron
annihilation is a signal of supersymmetry with bilinear R-Parity violation. In
this model, neutrino masses and mixing angles are generated due to mixing with
neutralinos. We show how parameters related to neutrino physics can be
determined at a $500 {\mathrm fb}^{-1}$ Linear Collider from measurements of
charged Higgs and stau production cross sections and decay rates. This can be
achieved in AMSB where charged Higgs and stau can have similar masses.
| [
{
"created": "Fri, 8 Nov 2002 13:01:46 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Diaz",
"M. A.",
""
],
[
"Lineros",
"R. A.",
""
],
[
"Rivera",
"M. A.",
""
]
] | Charged Higgs production in association with staus in electron positron annihilation is a signal of supersymmetry with bilinear R-Parity violation. In this model, neutrino masses and mixing angles are generated due to mixing with neutralinos. We show how parameters related to neutrino physics can be determined at a $500 {\mathrm fb}^{-1}$ Linear Collider from measurements of charged Higgs and stau production cross sections and decay rates. This can be achieved in AMSB where charged Higgs and stau can have similar masses. |
1204.6403 | Treleani Daniele | Daniele Treleani and Giorgio Calucci | Collisions of protons with light nuclei shed new light on nucleon
structure | 50 pages, 13 figures | null | 10.1103/PhysRevD.86.036003 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The high rates of multi-parton interactions at the LHC can provide a unique
opportunity to study the multi-parton structure of the hadron. To this purpose
high energy collisions of protons with nuclei are particularly suitable. The
rates of multi-parton interactions depend in fact both on the partonic
multiplicities and on the distributions of partons in transverse space, which
produce different effects on the cross section in pA collisions, as a function
of the atomic mass number A. Differently with respect to the case of
multi-parton interactions in pp collisions, the possibility of changing the
atomic mass number provides thus an additional handle to distinguish the
diverse contributions. Some relevant features of double parton interactions in
pD collisions have been discussed in a previous paper. In the present paper we
show how the effects of double and triple correlation terms of the multi-parton
structure can be disentangled, by comparing the rates of multiple parton
interactions in collisions of protons with D, Tritium and 3He.
| [
{
"created": "Sat, 28 Apr 2012 12:42:49 GMT",
"version": "v1"
}
] | 2013-05-30 | [
[
"Treleani",
"Daniele",
""
],
[
"Calucci",
"Giorgio",
""
]
] | The high rates of multi-parton interactions at the LHC can provide a unique opportunity to study the multi-parton structure of the hadron. To this purpose high energy collisions of protons with nuclei are particularly suitable. The rates of multi-parton interactions depend in fact both on the partonic multiplicities and on the distributions of partons in transverse space, which produce different effects on the cross section in pA collisions, as a function of the atomic mass number A. Differently with respect to the case of multi-parton interactions in pp collisions, the possibility of changing the atomic mass number provides thus an additional handle to distinguish the diverse contributions. Some relevant features of double parton interactions in pD collisions have been discussed in a previous paper. In the present paper we show how the effects of double and triple correlation terms of the multi-parton structure can be disentangled, by comparing the rates of multiple parton interactions in collisions of protons with D, Tritium and 3He. |
hep-ph/0303261 | David Akers | David Akers | Baryons in the Constituent-Quark Model | PDF only, 24 pages, 5 figures, 2 tables, source file available from
Author, major changes to revision | null | null | null | hep-ph | null | An elementary constituent-quark (CQ) model of mesons was previously
presented. In this paper, we continue research into a study of the baryons in
the constituent-quark model. Mac Gregor proposed a comprehensive model of
elementary particles for which both mesons and baryons shared common mass-band
structure in quantized units of m = 70 MeV, B= 140 MeV and X = 420 MeV. A
review of the baryon data is under taken for comparison with the CQ model. It
is shown in this paper that baryons possess an isospin I related to the mass
quantum m = 70 MeV and to the B = 140 MeV quantum (or the mass of the pion). In
order to establish a consistency with the quark model of Gell-Mann, we identify
the SU(3) baryon decuplet as a standard feature to be maintained with only
slight changes to the constituent-quark masses. By insisting on the J = 3/2,
P-states of the SU(3) baryon decuplet to be in the same CQ excitation states,
we are lead to establish baryon cores in the P-states with J = 1/2. Core
corrections to Mac Gregor's CQ model of baryons are presented. Exact shell
structure is found among all the baryons regardless of isospin as evidenced in
the data from the Particle Data Group listing. New baryons are predicted to
exist.
| [
{
"created": "Mon, 31 Mar 2003 16:19:46 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Apr 2003 15:30:16 GMT",
"version": "v2"
},
{
"created": "Thu, 3 Apr 2003 00:12:28 GMT",
"version": "v3"
},
{
"created": "Fri, 13 Jun 2003 15:08:06 GMT",
"version": "v4"
},
{
"cre... | 2007-05-23 | [
[
"Akers",
"David",
""
]
] | An elementary constituent-quark (CQ) model of mesons was previously presented. In this paper, we continue research into a study of the baryons in the constituent-quark model. Mac Gregor proposed a comprehensive model of elementary particles for which both mesons and baryons shared common mass-band structure in quantized units of m = 70 MeV, B= 140 MeV and X = 420 MeV. A review of the baryon data is under taken for comparison with the CQ model. It is shown in this paper that baryons possess an isospin I related to the mass quantum m = 70 MeV and to the B = 140 MeV quantum (or the mass of the pion). In order to establish a consistency with the quark model of Gell-Mann, we identify the SU(3) baryon decuplet as a standard feature to be maintained with only slight changes to the constituent-quark masses. By insisting on the J = 3/2, P-states of the SU(3) baryon decuplet to be in the same CQ excitation states, we are lead to establish baryon cores in the P-states with J = 1/2. Core corrections to Mac Gregor's CQ model of baryons are presented. Exact shell structure is found among all the baryons regardless of isospin as evidenced in the data from the Particle Data Group listing. New baryons are predicted to exist. |
hep-ph/0207035 | Giuesepp Battistoni | G.Battistoni, A.Ferrari, T.Montaruli and P.R.Sala | The FLUKA atmospheric neutrino flux calculation | Papper has been corrected since the cosine of Zenith angle in flux
tables was erraneously inverted. Also, fig. 17 and 18 have been corrected | Astropart.Phys.19:269-290,2003; Erratum-ibid.19:291-294,2003 | 10.1016/S0927-6505(02)00246-3 | null | hep-ph astro-ph | null | The 3-dimensional (3-D) calculation of the atmospheric neutrino flux by means
of the FLUKA Monte Carlo model is here described in all details, starting from
the latest data on primary cosmic ray spectra. The importance of a 3-D
calculation and of its consequences have been already debated in a previous
paper. Here instead the focus is on the absolute flux. We stress the relevant
aspects of the hadronic interaction model of FLUKA in the atmospheric neutrino
flux calculation. This model is constructed and maintained so to provide a high
degree of accuracy in the description of particle production. The accuracy
achieved in the comparison with data from accelerators and cross checked with
data on particle production in atmosphere certifies the reliability of shower
calculation in atmosphere. The results presented here can be already used for
analysis by current experiments on atmospheric neutrinos. However they
represent an intermediate step towards a final release, since this calculation
does not yet include the bending of charged particles in atmosphere. On the
other hand this last aspect, while requiring a considerable effort in a fully
3-D description of the Earth, if a high level of accuracy has to be maintained,
does not affect in a significant way the analysis of atmospheric neutrino
events.
| [
{
"created": "Tue, 2 Jul 2002 14:26:02 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jan 2003 11:08:48 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Battistoni",
"G.",
""
],
[
"Ferrari",
"A.",
""
],
[
"Montaruli",
"T.",
""
],
[
"Sala",
"P. R.",
""
]
] | The 3-dimensional (3-D) calculation of the atmospheric neutrino flux by means of the FLUKA Monte Carlo model is here described in all details, starting from the latest data on primary cosmic ray spectra. The importance of a 3-D calculation and of its consequences have been already debated in a previous paper. Here instead the focus is on the absolute flux. We stress the relevant aspects of the hadronic interaction model of FLUKA in the atmospheric neutrino flux calculation. This model is constructed and maintained so to provide a high degree of accuracy in the description of particle production. The accuracy achieved in the comparison with data from accelerators and cross checked with data on particle production in atmosphere certifies the reliability of shower calculation in atmosphere. The results presented here can be already used for analysis by current experiments on atmospheric neutrinos. However they represent an intermediate step towards a final release, since this calculation does not yet include the bending of charged particles in atmosphere. On the other hand this last aspect, while requiring a considerable effort in a fully 3-D description of the Earth, if a high level of accuracy has to be maintained, does not affect in a significant way the analysis of atmospheric neutrino events. |
hep-ph/9510239 | Chung-Yi Wu | Chung-Yi Wu (National Cheng Kung University) | Structural Aspects of the Proton in the Chiral Quark Model | 10 pages, LaTeX | Mod.Phys.Lett. A12 (1997) 1145-1152 | 10.1142/S0217732397001175 | NCKU-HEP/95-05 | hep-ph | null | We calculate with chiral symmetry the parton contents of the proton based on
a two-component wave function. The calculation results give significant
sea-quark contents and, especially, the intrinsic gluon polarization produced
at a more fundamental level.
| [
{
"created": "Fri, 6 Oct 1995 14:50:56 GMT",
"version": "v1"
},
{
"created": "Sat, 7 Oct 1995 05:14:34 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Wu",
"Chung-Yi",
"",
"National Cheng Kung University"
]
] | We calculate with chiral symmetry the parton contents of the proton based on a two-component wave function. The calculation results give significant sea-quark contents and, especially, the intrinsic gluon polarization produced at a more fundamental level. |
0907.3916 | Michael Ramsey-Musolf | Michael J. Ramsey-Musolf | Fundamental Symmetries of the Early Universe and the Precision Frontier | Proceedings of CIPANP 2009; 9 pages, 1 figure | AIP Conf.Proc.1182:635-643,2009 | 10.1063/1.3293888 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The search for the next Standard Model of fundamental interactions is being
carried out at two frontiers: the high energy frontier involving the Tevatron
and Large Hadron Collider, and the high precision frontier where the focus is
largely on low energy experiments. I discuss the unique and powerful window on
new physics provided by the precision frontier and its complementarity to the
information we hope to gain from present and future colliders.
| [
{
"created": "Thu, 23 Jul 2009 15:47:54 GMT",
"version": "v1"
}
] | 2010-01-15 | [
[
"Ramsey-Musolf",
"Michael J.",
""
]
] | The search for the next Standard Model of fundamental interactions is being carried out at two frontiers: the high energy frontier involving the Tevatron and Large Hadron Collider, and the high precision frontier where the focus is largely on low energy experiments. I discuss the unique and powerful window on new physics provided by the precision frontier and its complementarity to the information we hope to gain from present and future colliders. |
0704.1590 | Mitsuru Kakizaki | Manuel Drees, Hoernisa Iminniyaz, Mitsuru Kakizaki | Constraints on the Very Early Universe from Thermal WIMP Dark Matter | 23 pages, 8 figures, comments added | Phys.Rev.D76:103524,2007 | 10.1103/PhysRevD.76.103524 | null | hep-ph astro-ph | null | We investigate the relic density n_\chi of non-relativistic long-lived or
stable particles \chi in non-standard cosmological scenarios. We calculate the
relic abundance starting from arbitrary initial temperatures of the
radiation-dominated epoch, and derive the lower bound on the initial
temperature T_0 \geq m_\chi/23, assuming that thermally produced \chi particles
account for the dark matter energy density in the universe; this bound holds
for all \chi annihilation cross sections. We also investigate cosmological
scenarios with modified expansion rate. Even in this case an approximate
formula similar to the standard one is capable of predicting the final relic
abundance correctly. Choosing the \chi annihilation cross section such that the
observed cold dark matter abundance is reproduced in standard cosmology, we
constrain possible modifications of the expansion rate at T \sim m_\chi/20,
well before Big Bang nucleosynthesis.
| [
{
"created": "Thu, 12 Apr 2007 14:36:24 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Nov 2007 21:47:31 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Drees",
"Manuel",
""
],
[
"Iminniyaz",
"Hoernisa",
""
],
[
"Kakizaki",
"Mitsuru",
""
]
] | We investigate the relic density n_\chi of non-relativistic long-lived or stable particles \chi in non-standard cosmological scenarios. We calculate the relic abundance starting from arbitrary initial temperatures of the radiation-dominated epoch, and derive the lower bound on the initial temperature T_0 \geq m_\chi/23, assuming that thermally produced \chi particles account for the dark matter energy density in the universe; this bound holds for all \chi annihilation cross sections. We also investigate cosmological scenarios with modified expansion rate. Even in this case an approximate formula similar to the standard one is capable of predicting the final relic abundance correctly. Choosing the \chi annihilation cross section such that the observed cold dark matter abundance is reproduced in standard cosmology, we constrain possible modifications of the expansion rate at T \sim m_\chi/20, well before Big Bang nucleosynthesis. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.