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
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0901.4599
|
Bjoern Duling
|
Bjoern Duling
|
K and B meson mixing in warped extra dimensions with custodial
protection
|
9 pages, 4 figures. To appear in the Discrete'08 proceedings
|
J.Phys.Conf.Ser.171:012061,2009
|
10.1088/1742-6596/171/1/012061
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
After a brief theoretical introduction of the warped extra-dimensional model
with custodial protection the results of arXiv:0809.1073 [hep-ph] are
presented. In this work we analyze the impact of Kaluza-Klein (KK) gauge boson
modes on Delta F=2 observables, for the first time considering the full
operator basis and including NLO renormalization group running. It is pointed
out that the dominant contribution in the B-system does not come from the KK
gluon, but that contributions from KK excitations of the weak gauge bosons are
competitive. In a numerical analysis we assess the amount of fine-tuning
necessary for obtaining realistic values for quark masses and mixings and at
the same time realistic values for epsilon_K, the measure for CP violation in K
meson mixing. We are able to show that a mass of the lightest KK gauge boson of
2-3 TeV, and hence in the reach of the LHC, is still possible for moderate
fine-tuning. These results enable us to make predictions for not yet measured
Delta F=2 observables, such as S_\psi\phi and A_s^SL, which can differ
significantly from their SM values.
|
[
{
"created": "Thu, 29 Jan 2009 16:09:38 GMT",
"version": "v1"
}
] |
2009-07-22
|
[
[
"Duling",
"Bjoern",
""
]
] |
After a brief theoretical introduction of the warped extra-dimensional model with custodial protection the results of arXiv:0809.1073 [hep-ph] are presented. In this work we analyze the impact of Kaluza-Klein (KK) gauge boson modes on Delta F=2 observables, for the first time considering the full operator basis and including NLO renormalization group running. It is pointed out that the dominant contribution in the B-system does not come from the KK gluon, but that contributions from KK excitations of the weak gauge bosons are competitive. In a numerical analysis we assess the amount of fine-tuning necessary for obtaining realistic values for quark masses and mixings and at the same time realistic values for epsilon_K, the measure for CP violation in K meson mixing. We are able to show that a mass of the lightest KK gauge boson of 2-3 TeV, and hence in the reach of the LHC, is still possible for moderate fine-tuning. These results enable us to make predictions for not yet measured Delta F=2 observables, such as S_\psi\phi and A_s^SL, which can differ significantly from their SM values.
|
1304.3356
|
Angel Gomez Nicola
|
A. Gomez Nicola, J. Ruiz de Elvira, R. Torres Andres
|
Chiral Symmetry Restoration and Scalar-Pseudoscalar partners in QCD
|
9 pages, 4 figures. Enlarged version to appear in Phys.Rev.D
|
Phys. Rev. D 88, 076007 (2013)
|
10.1103/PhysRevD.88.076007
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We describe Scalar-Pseudoscalar partner degeneration at the QCD chiral
transition in terms of the dominant low-energy physical states for the light
quark sector. First, we obtain within model-independent one-loop Chiral
Perturbation Theory (ChPT) that the QCD pseudoscalar susceptibility is
proportional to the quark condensate at low $T$. Next, we show that this
chiral-restoring behaviour for $\chi_P$ is compatible with recent lattice
results for screening masses and gives rise to degeneration between the scalar
and pseudoscalar susceptibilities ($\chi_S$, $\chi_P$) around the transition
point, consistently with an O(4)-like current restoration pattern. This
scenario is clearly confirmed by lattice data when we compare $\chi_S(T)$ with
the quark condensate, expected to scale as $\chi_P(T)$. Finally, we show that
saturating $\chi_S$ with the $\sigma/f_0(500)$ broad resonance observed in pion
scattering and including its finite temperature dependence, allows to describe
the peak structure of $\chi_S(T)$ in lattice data and the associated critical
temperature. This is carried out within a unitarized ChPT scheme which
generates the resonant state dynamically and is also consistent with partner
degeneration.
|
[
{
"created": "Thu, 11 Apr 2013 16:16:05 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Oct 2013 18:54:44 GMT",
"version": "v2"
}
] |
2013-10-30
|
[
[
"Nicola",
"A. Gomez",
""
],
[
"de Elvira",
"J. Ruiz",
""
],
[
"Andres",
"R. Torres",
""
]
] |
We describe Scalar-Pseudoscalar partner degeneration at the QCD chiral transition in terms of the dominant low-energy physical states for the light quark sector. First, we obtain within model-independent one-loop Chiral Perturbation Theory (ChPT) that the QCD pseudoscalar susceptibility is proportional to the quark condensate at low $T$. Next, we show that this chiral-restoring behaviour for $\chi_P$ is compatible with recent lattice results for screening masses and gives rise to degeneration between the scalar and pseudoscalar susceptibilities ($\chi_S$, $\chi_P$) around the transition point, consistently with an O(4)-like current restoration pattern. This scenario is clearly confirmed by lattice data when we compare $\chi_S(T)$ with the quark condensate, expected to scale as $\chi_P(T)$. Finally, we show that saturating $\chi_S$ with the $\sigma/f_0(500)$ broad resonance observed in pion scattering and including its finite temperature dependence, allows to describe the peak structure of $\chi_S(T)$ in lattice data and the associated critical temperature. This is carried out within a unitarized ChPT scheme which generates the resonant state dynamically and is also consistent with partner degeneration.
|
1112.2047
|
Claude Semay
|
Fabien Buisseret, Nicolas Matagne, Claude Semay
|
Spin contribution to light baryons in different large-$N$ limits
|
1 figure
|
Phys. Rev. D 85, 036010 (2012)
|
10.1103/PhysRevD.85.036010
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate the spin contribution to light baryon ground states in three
inequivalent large-$N$ limits: 't Hooft, QCD antisymmetric and QCD symmetric.
Our framework is a constituent quark model with a relativistic Hamiltonian
containing a stringlike confinement and a one-gluon exchange term. Two
spin-dependent potentials are considered and treated as perturbations: the
color magnetic interaction stemming from the one-gluon exchange process and the
chiral boson exchange interaction. We analytically prove that the spin
contributions scale like $S(S+1)/n_q$, where $S$ is the total spin and $n_q$ is
the number of quark, in agreement with diagrammatic methods. Both potentials
yield also $S$-independent contributions which scale at most as O$(n_q)$.
|
[
{
"created": "Fri, 9 Dec 2011 08:39:45 GMT",
"version": "v1"
}
] |
2012-02-29
|
[
[
"Buisseret",
"Fabien",
""
],
[
"Matagne",
"Nicolas",
""
],
[
"Semay",
"Claude",
""
]
] |
We investigate the spin contribution to light baryon ground states in three inequivalent large-$N$ limits: 't Hooft, QCD antisymmetric and QCD symmetric. Our framework is a constituent quark model with a relativistic Hamiltonian containing a stringlike confinement and a one-gluon exchange term. Two spin-dependent potentials are considered and treated as perturbations: the color magnetic interaction stemming from the one-gluon exchange process and the chiral boson exchange interaction. We analytically prove that the spin contributions scale like $S(S+1)/n_q$, where $S$ is the total spin and $n_q$ is the number of quark, in agreement with diagrammatic methods. Both potentials yield also $S$-independent contributions which scale at most as O$(n_q)$.
|
1310.1070
|
Martin Bauer
|
Kaustubh Agashe, Martin Bauer, Florian Goertz, Seung J. Lee, Luca
Vecchi, Lian-Tao Wang, Felix Yu
|
Constraining RS Models by Future Flavor and Collider Measurements: A
Snowmass Whitepaper
|
20 pages, 9 figures
| null | null |
FERMILAB-CONF-13-435-T
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Randall-Sundrum models are models of quark flavor, because they explain the
hierarchies in the quark masses and mixings in terms of order one localization
parameters of extra dimensional wavefunctions. The same small numbers which
generate the light quark masses suppress contributions to flavor violating tree
level amplitudes. In this note we update universal constraints from electroweak
precision parameters and demonstrate how future measurements of flavor
violation in ultra rare decay channels of Kaons and B mesons will constrain the
parameter space of this type of models. We show how collider signatures are
correlated with these flavor measurements and compute projected limits for
direct searches at the 14 TeV LHC run, a 14 TeV LHC luminosity upgrade, a 33
TeV LHC energy upgrade, and a potential 100 TeV machine. We further discuss the
effects of a warped model of leptons in future measurements of lepton flavor
violation.
|
[
{
"created": "Thu, 3 Oct 2013 19:17:52 GMT",
"version": "v1"
}
] |
2013-10-04
|
[
[
"Agashe",
"Kaustubh",
""
],
[
"Bauer",
"Martin",
""
],
[
"Goertz",
"Florian",
""
],
[
"Lee",
"Seung J.",
""
],
[
"Vecchi",
"Luca",
""
],
[
"Wang",
"Lian-Tao",
""
],
[
"Yu",
"Felix",
""
]
] |
Randall-Sundrum models are models of quark flavor, because they explain the hierarchies in the quark masses and mixings in terms of order one localization parameters of extra dimensional wavefunctions. The same small numbers which generate the light quark masses suppress contributions to flavor violating tree level amplitudes. In this note we update universal constraints from electroweak precision parameters and demonstrate how future measurements of flavor violation in ultra rare decay channels of Kaons and B mesons will constrain the parameter space of this type of models. We show how collider signatures are correlated with these flavor measurements and compute projected limits for direct searches at the 14 TeV LHC run, a 14 TeV LHC luminosity upgrade, a 33 TeV LHC energy upgrade, and a potential 100 TeV machine. We further discuss the effects of a warped model of leptons in future measurements of lepton flavor violation.
|
1202.3556
|
Alexander Semke
|
A. Semke and M. F. M. Lutz
|
Strangeness in the baryon ground states
|
15 pages, 5 tables, 3 figures. There are two significant extensions
in the revised manuscript. First, a precise determination of the axial
coupling constants F and D from the lattice data on the baryon masses is
provided. Second, it is shown that the lattice data of the QCDSF-UKQCD group
on the baryon masses in the flavor symmetric limit are recovered. The 3rd
version is the published version
| null |
10.1016/j.physletb.2012.09.008
| null |
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We compute the strangeness content of the baryon octet and decuplet states
based on an analysis of recent lattice simulations of the BMW, PACS, LHPC and
HSC groups for the pion-mass dependence of the baryon masses. Our results rely
on the relativistic chiral Lagrangian and large-$N_c$ sum rule estimates of the
counter terms relevant for the baryon masses at N$^3$LO. A partial summation is
implied by the use of physical baryon and meson masses in the one-loop
contributions to the baryon self energies. A simultaneous description of the
lattice results of the BMW, LHPC, PACS and HSC groups is achieved. From a
global fit we determine the axial coupling constants $F\simeq 0.45$ and $D
\simeq 0.80 $ in agreement with their values extracted from semi-leptonic
decays of the baryons. Moreover, various flavor symmetric limits of baron octet
and decuplet masses as obtained by the QCDSF-UKQCD group are recovered. We
predict the pion- and strangeness sigma terms and the pion-mass dependence of
the octet and decuplet ground states at different strange quark masses.
|
[
{
"created": "Thu, 16 Feb 2012 10:33:58 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Jun 2012 18:59:16 GMT",
"version": "v2"
},
{
"created": "Fri, 14 Sep 2012 19:06:12 GMT",
"version": "v3"
}
] |
2015-06-04
|
[
[
"Semke",
"A.",
""
],
[
"Lutz",
"M. F. M.",
""
]
] |
We compute the strangeness content of the baryon octet and decuplet states based on an analysis of recent lattice simulations of the BMW, PACS, LHPC and HSC groups for the pion-mass dependence of the baryon masses. Our results rely on the relativistic chiral Lagrangian and large-$N_c$ sum rule estimates of the counter terms relevant for the baryon masses at N$^3$LO. A partial summation is implied by the use of physical baryon and meson masses in the one-loop contributions to the baryon self energies. A simultaneous description of the lattice results of the BMW, LHPC, PACS and HSC groups is achieved. From a global fit we determine the axial coupling constants $F\simeq 0.45$ and $D \simeq 0.80 $ in agreement with their values extracted from semi-leptonic decays of the baryons. Moreover, various flavor symmetric limits of baron octet and decuplet masses as obtained by the QCDSF-UKQCD group are recovered. We predict the pion- and strangeness sigma terms and the pion-mass dependence of the octet and decuplet ground states at different strange quark masses.
|
2108.05398
|
Yohei Ema
|
Yohei Ema, Ting Gao, Maxim Pospelov
|
Improved indirect limits on muon EDM
|
5 pages, 2 figures; v2: references added; v3: supplemental material
added, version accepted in PRL
| null | null |
DESY 21-118
|
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
Given current discrepancy in muon $g-2$ and future dedicated efforts to
measure muon electric dipole moment (EDM) $d_\mu$, we assess the indirect
constraints imposed on $d_\mu$ by the EDM measurements performed with heavy
atoms and molecules. We notice that the dominant muon EDM effect arises via the
muon-loop induced "light-by-light" $CP$-odd amplitude $\propto{\bf B}{\bf
E}^3$, and in the vicinity of a large nucleus the corresponding parameter of
expansion can be significant, $eE_{\rm nucl}/m_\mu^2 \sim 0.04$. We compute the
$d_\mu$-induced Schiff moment of the $^{199}$Hg nucleus, and the linear
combination of $d_e$ and semileptonic $C_S$ operator (dominant in this case)
that determine the $CP$-odd effects in ThO molecule. The results,
$d_\mu(^{199}{\rm Hg}) < 6\times 10^{-20}e$cm and $d_\mu({\rm ThO}) < 2\times
10^{-20}e$cm, constitute approximately three- and nine-fold improvements over
the limits on $d_\mu$ extracted from the BNL muon beam experiment.
|
[
{
"created": "Wed, 11 Aug 2021 18:27:27 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Oct 2021 02:31:22 GMT",
"version": "v2"
},
{
"created": "Sat, 26 Mar 2022 18:51:53 GMT",
"version": "v3"
}
] |
2022-03-29
|
[
[
"Ema",
"Yohei",
""
],
[
"Gao",
"Ting",
""
],
[
"Pospelov",
"Maxim",
""
]
] |
Given current discrepancy in muon $g-2$ and future dedicated efforts to measure muon electric dipole moment (EDM) $d_\mu$, we assess the indirect constraints imposed on $d_\mu$ by the EDM measurements performed with heavy atoms and molecules. We notice that the dominant muon EDM effect arises via the muon-loop induced "light-by-light" $CP$-odd amplitude $\propto{\bf B}{\bf E}^3$, and in the vicinity of a large nucleus the corresponding parameter of expansion can be significant, $eE_{\rm nucl}/m_\mu^2 \sim 0.04$. We compute the $d_\mu$-induced Schiff moment of the $^{199}$Hg nucleus, and the linear combination of $d_e$ and semileptonic $C_S$ operator (dominant in this case) that determine the $CP$-odd effects in ThO molecule. The results, $d_\mu(^{199}{\rm Hg}) < 6\times 10^{-20}e$cm and $d_\mu({\rm ThO}) < 2\times 10^{-20}e$cm, constitute approximately three- and nine-fold improvements over the limits on $d_\mu$ extracted from the BNL muon beam experiment.
|
2203.02981
|
J.K. Chen
|
Jiao-Kai Chen
|
Revisiting the pion Regge trajectories
|
14 pages, 9 figures, 4 tables. V3: Nucl. Phys. B
|
Nucl. Phys. B 983 (2022) 115911
|
10.1016/j.nuclphysb.2022.115911
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We propose a model-independent ansatz
$M={\beta_x}\left(x+c_0\right)^{\nu}+c_1$ ($x=l,\,n_r$) and then use it to fit
the orbital and radial pion Regge trajectories without the preset values. It is
shown that nonzero $c_1$ is reasonable and acceptable. Nonzero $c_1$ gives an
explanation for the nonlinearity of the pion Regge trajectories in the usually
employed $(M^2,\,x)$ plane. As $m_R$ or $c_1$ is chosen appropriately, both the
orbital and radial pion Regge trajectories are linear in the $((M-m_R)^2,\,x)$
plane whether the $\pi^0$ is included or not on the Regge trajectories. The
fitted pion Regge trajectories suggest $0.45\le\nu\le0.5$, which indicates the
confining potential $r^a$ with $9/11{\le}a\le1$. Moreover, it is illustrated in
the appendix B that $m_R$ can be nonzero for the light nonstrange mesons. We
present discussions in the appendix A on the structure of the Regge
trajectories plotted in the $(M,\,x)$ plane and on the structure of the Regge
trajectories in the $((M-m_R)^2,\,x)$ plane based on the potential models and
the string models.
|
[
{
"created": "Sun, 6 Mar 2022 15:10:51 GMT",
"version": "v1"
},
{
"created": "Sun, 17 Jul 2022 10:12:12 GMT",
"version": "v2"
},
{
"created": "Sun, 7 Aug 2022 04:03:48 GMT",
"version": "v3"
}
] |
2022-08-17
|
[
[
"Chen",
"Jiao-Kai",
""
]
] |
We propose a model-independent ansatz $M={\beta_x}\left(x+c_0\right)^{\nu}+c_1$ ($x=l,\,n_r$) and then use it to fit the orbital and radial pion Regge trajectories without the preset values. It is shown that nonzero $c_1$ is reasonable and acceptable. Nonzero $c_1$ gives an explanation for the nonlinearity of the pion Regge trajectories in the usually employed $(M^2,\,x)$ plane. As $m_R$ or $c_1$ is chosen appropriately, both the orbital and radial pion Regge trajectories are linear in the $((M-m_R)^2,\,x)$ plane whether the $\pi^0$ is included or not on the Regge trajectories. The fitted pion Regge trajectories suggest $0.45\le\nu\le0.5$, which indicates the confining potential $r^a$ with $9/11{\le}a\le1$. Moreover, it is illustrated in the appendix B that $m_R$ can be nonzero for the light nonstrange mesons. We present discussions in the appendix A on the structure of the Regge trajectories plotted in the $(M,\,x)$ plane and on the structure of the Regge trajectories in the $((M-m_R)^2,\,x)$ plane based on the potential models and the string models.
|
hep-ph/0102211
|
Uma Mahanta
|
Uma Mahanta
|
Constraining new physics in the Tev range by the recent BNL measurement
of (g-2)_{\mu}
|
Final version to be published in Physics Letters B
|
Phys.Lett. B511 (2001) 235-239
|
10.1016/S0370-2693(01)00637-2
| null |
hep-ph
| null |
In this paper we study the implications of the recent high precision
measurement of (g-2)_{\mu} by BNL on new heavy physics beyond the SM in a model
independent way. We find that if the new physics responsible for the muon
anomaly is due to d=6 direct operators then they could arise from the following
follwing three broad classes of new physics a) new particles in the few hundred
Gev range with weak gauge coupling b) strongly interacting particles and
resonances in the few Tev range and c) massive Kaluza-Klein modes of the
graviton in the Tev range with couplings to SM particles of the order of
${E\over (Tev)}$.
|
[
{
"created": "Fri, 16 Feb 2001 18:24:46 GMT",
"version": "v1"
},
{
"created": "Sun, 18 Feb 2001 12:23:38 GMT",
"version": "v2"
},
{
"created": "Sun, 18 Mar 2001 13:42:22 GMT",
"version": "v3"
},
{
"created": "Tue, 19 Jun 2001 11:22:53 GMT",
"version": "v4"
}
] |
2009-11-07
|
[
[
"Mahanta",
"Uma",
""
]
] |
In this paper we study the implications of the recent high precision measurement of (g-2)_{\mu} by BNL on new heavy physics beyond the SM in a model independent way. We find that if the new physics responsible for the muon anomaly is due to d=6 direct operators then they could arise from the following follwing three broad classes of new physics a) new particles in the few hundred Gev range with weak gauge coupling b) strongly interacting particles and resonances in the few Tev range and c) massive Kaluza-Klein modes of the graviton in the Tev range with couplings to SM particles of the order of ${E\over (Tev)}$.
|
1209.0042
|
Qingfeng Li
|
Qingfeng Li, Gunnar Graef and Marcus Bleicher
|
UrQMD calculations of two-pion HBT correlations in p+p and Pb+Pb
collisions at LHC energies
|
9 pages, 4 figures, 1 table. Talk given by Qingfeng Li at the 11th
International Conference on Nucleus-Nucleus Collisions (NN2012), San Antonio,
Texas, USA, May 27-June 1, 2012. To appear in the NN2012 Proceedings in
Journal of Physics: Conference Series (JPCS)
| null |
10.1088/1742-6596/420/1/012039
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Two-pion Hanbury-Brown-Twiss (HBT) correlations for p+p and central Pb+Pb
collisions at the Large-Hadron-Collider (LHC) energies are investigated with
the ultra-relativistic quantum molecular dynamics model combined with a
correlation afterburner. The transverse momentum dependence of the
Pratt-Bertsch HBT radii $R_{long}$, $R_{out}$, and $R_{side}$ is extracted from
a three-dimensional Gaussian fit to the correlator in the longitudinal
co-moving system. In the p+p case, the dependence of correlations on the
charged particle multiplicity and formation time is explored and the data
allows to constrain the formation time in the string fragmentation to $\tau_f
\leq 0.8$ fm/c. In the Pb+Pb case, it is found that $R_{out}$ is overpredicted
by nearly 50%. The LHC results are also compared to data from the STAR
experiment at RHIC. For both energies we find that the calculated
$R_{out}/R_{side}$ ratio is always larger than data, indicating that the
emission in the model is less explosive than observed in the data.
|
[
{
"created": "Sat, 1 Sep 2012 01:06:35 GMT",
"version": "v1"
}
] |
2015-06-11
|
[
[
"Li",
"Qingfeng",
""
],
[
"Graef",
"Gunnar",
""
],
[
"Bleicher",
"Marcus",
""
]
] |
Two-pion Hanbury-Brown-Twiss (HBT) correlations for p+p and central Pb+Pb collisions at the Large-Hadron-Collider (LHC) energies are investigated with the ultra-relativistic quantum molecular dynamics model combined with a correlation afterburner. The transverse momentum dependence of the Pratt-Bertsch HBT radii $R_{long}$, $R_{out}$, and $R_{side}$ is extracted from a three-dimensional Gaussian fit to the correlator in the longitudinal co-moving system. In the p+p case, the dependence of correlations on the charged particle multiplicity and formation time is explored and the data allows to constrain the formation time in the string fragmentation to $\tau_f \leq 0.8$ fm/c. In the Pb+Pb case, it is found that $R_{out}$ is overpredicted by nearly 50%. The LHC results are also compared to data from the STAR experiment at RHIC. For both energies we find that the calculated $R_{out}/R_{side}$ ratio is always larger than data, indicating that the emission in the model is less explosive than observed in the data.
|
1611.08511
|
Howard Baer
|
Howard Baer, Vernon Barger, Natsumi Nagata and Michael Savoy
|
A top-squark hunter's guide
|
20 pages with 10 .png figures; version 2 contains updated b->s gamma
data and added references
|
Phys. Rev. D 95, 055012 (2017)
|
10.1103/PhysRevD.95.055012
|
UT-16-32
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In supersymmetric models with radiatively-driven naturalness and light
higgsinos, the top squarks may lie in the 0.5- 3TeV range and thus only a
fraction of natural parameter space is accessible to LHC searches. We outline
the range of top squark and lightest SUSY particle masses preferred by
electroweak naturalness in the standard parameter space plane. We note that the
branching fraction for b-> s\gamma decay favors top squarks much heavier than
500 GeV. Such a range of top-squark mass values is in contrast to previous
expectations where m(stop)<500 GeV had been considered natural. In radiative
natural SUSY, top squarks decay roughly equally via t1-> bW1 and Z_{1,2} where
W1 and Z_{1,2} are higgsino-like electroweak-inos. Thus, top squark pair
production should yield all of t\bar{t}+\eslt, t\bar{b}+\eslt, b\bar{t}+\eslt
and b\bar{b}+\eslt signatures at comparable rates. We propose that future LHC
top squark searches take place within a semi-simplified model which corresponds
more closely to expectations from theory.
|
[
{
"created": "Fri, 25 Nov 2016 16:35:31 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Dec 2016 17:44:06 GMT",
"version": "v2"
}
] |
2017-03-22
|
[
[
"Baer",
"Howard",
""
],
[
"Barger",
"Vernon",
""
],
[
"Nagata",
"Natsumi",
""
],
[
"Savoy",
"Michael",
""
]
] |
In supersymmetric models with radiatively-driven naturalness and light higgsinos, the top squarks may lie in the 0.5- 3TeV range and thus only a fraction of natural parameter space is accessible to LHC searches. We outline the range of top squark and lightest SUSY particle masses preferred by electroweak naturalness in the standard parameter space plane. We note that the branching fraction for b-> s\gamma decay favors top squarks much heavier than 500 GeV. Such a range of top-squark mass values is in contrast to previous expectations where m(stop)<500 GeV had been considered natural. In radiative natural SUSY, top squarks decay roughly equally via t1-> bW1 and Z_{1,2} where W1 and Z_{1,2} are higgsino-like electroweak-inos. Thus, top squark pair production should yield all of t\bar{t}+\eslt, t\bar{b}+\eslt, b\bar{t}+\eslt and b\bar{b}+\eslt signatures at comparable rates. We propose that future LHC top squark searches take place within a semi-simplified model which corresponds more closely to expectations from theory.
|
2308.07133
|
Shi-Ping He
|
Shi-Ping He
|
Handbook of the analytic and expansion formulae for the muon $g-2$
anomaly
|
25 pages, 1 captioned figure, 2 tables. This manuscript will continue
to be updated. Suggestions and comments are welcome
| null | null | null |
hep-ph hep-ex
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
Since announcement of the muon $g-2$ anomaly, plenty of papers have devoted
to this anomaly. The approximate formulae are always adopted when determining
the new physics contributions to $(g-2)_{\mu}$, while clear scope of
applications are always absent. This manuscript is dedicated to the
comprehensive analytical results and approximations for the canonical
interactions at one-loop level, which can be a useful handbook for the model
builders. Here, we only collect the analytic and approximate expressions for
the scalar mediator case. For the expressions of vector mediator case, they
will appear in the future.
|
[
{
"created": "Mon, 14 Aug 2023 13:39:24 GMT",
"version": "v1"
}
] |
2023-08-15
|
[
[
"He",
"Shi-Ping",
""
]
] |
Since announcement of the muon $g-2$ anomaly, plenty of papers have devoted to this anomaly. The approximate formulae are always adopted when determining the new physics contributions to $(g-2)_{\mu}$, while clear scope of applications are always absent. This manuscript is dedicated to the comprehensive analytical results and approximations for the canonical interactions at one-loop level, which can be a useful handbook for the model builders. Here, we only collect the analytic and approximate expressions for the scalar mediator case. For the expressions of vector mediator case, they will appear in the future.
|
hep-ph/9312344
|
Dr. Dubravko Klabucar
|
D. Klabu\v{c}ar
|
Instantons And Baryon Mass Splittings in the MIT Bag Model
|
23 pages, report ZTF-93/10 (to appear in Phys.Rev. D)
|
Phys.Rev. D49 (1994) 1506-1512
|
10.1103/PhysRevD.49.1506
| null |
hep-ph
| null |
The contribution of instanton-induced effective inter-quark interactions to
the baryon mass splittings was considered in the bag model. It is found that
results are different from those obtained in the constituent quark model where
the instanton effects are like those from one-gluon exchange. This is because
in the context of the bag model calculation the one-body instanton-induced
interaction has to be included.
|
[
{
"created": "Mon, 27 Dec 1993 17:17:20 GMT",
"version": "v1"
}
] |
2009-10-22
|
[
[
"Klabučar",
"D.",
""
]
] |
The contribution of instanton-induced effective inter-quark interactions to the baryon mass splittings was considered in the bag model. It is found that results are different from those obtained in the constituent quark model where the instanton effects are like those from one-gluon exchange. This is because in the context of the bag model calculation the one-body instanton-induced interaction has to be included.
|
hep-ph/9901232
|
Mohammad Ahmady
|
Mohammad R. Ahmady (RIKEN, Wako) and Victor Elias (Western Ontario)
|
Nonperturbative QCD corrections to the effective coefficients of the
four-Fermi operators
|
12 pages, Revtex, 3 postscript figures (included)
|
Phys.Rev. D60 (1999) 074013
|
10.1103/PhysRevD.60.074013
|
RIKEN-AF-NP-295
|
hep-ph
| null |
We calculate the leading nonperturbative contributions to the effective
Wilson coefficient of the four-fermion operators arising from the QCD penguin,
and we demonstrate how the usual perturbative one loop contribution is
augmented by nonperturbative condensates. These corrections, which are obtained
by quark and gluon condensate insertions into the quark loops, enter at the
next-to-leading logarithm precision.
Our results indicate for the charmed quark loop that the gluon condensate
contribution is quite sensitive to the momentum transfer to the quark-antiquark
pair.
|
[
{
"created": "Wed, 6 Jan 1999 06:23:43 GMT",
"version": "v1"
}
] |
2016-09-06
|
[
[
"Ahmady",
"Mohammad R.",
"",
"RIKEN, Wako"
],
[
"Elias",
"Victor",
"",
"Western Ontario"
]
] |
We calculate the leading nonperturbative contributions to the effective Wilson coefficient of the four-fermion operators arising from the QCD penguin, and we demonstrate how the usual perturbative one loop contribution is augmented by nonperturbative condensates. These corrections, which are obtained by quark and gluon condensate insertions into the quark loops, enter at the next-to-leading logarithm precision. Our results indicate for the charmed quark loop that the gluon condensate contribution is quite sensitive to the momentum transfer to the quark-antiquark pair.
|
1708.02764
|
Vinicius Rodrigues Debastiani
|
M. Bayar and V. R. Debastiani
|
$a_0(980) - f_0(980)$ mixing in $\chi_{c1} \to \pi^0 f_0(980) \to \pi^0
\pi^+ \pi^-$ and $\chi_{c1} \to \pi^0 a_0(980) \to \pi^0 \pi^0 \eta$
|
revised manuscript, new figures, new references; 8 pages, 6 figures
|
Phys. Lett. B 775, 94 (2017)
|
10.1016/j.physletb.2017.10.061
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the isospin breaking in the reactions $\chi_{c1} \to \pi^0 \pi^+
\pi^-$ and $\chi_{c1} \to \pi^0 \pi^0 \eta$ and its relation to the $a_0(980) -
f_0(980)$ mixing, which was measured by the BESIII Collaboration. We show that
the same theoretical model previously developed to study the $\chi_{c1} \to
\eta \pi^+ \pi^-$ reaction (also measured by BESIII), and further explored in
the predictions to the $\eta_{c} \to \eta \pi^+ \pi^-$, can be successfully
employed in the present study. We assume that the $\chi_{c1}$ behaves as an
$SU(3)$ singlet to find the weight in which trios of pseudoscalars are created,
followed by the final state interaction of pairs of mesons to describe how the
$a_0(980)$ and $f_0(980)$ are dynamically generated, using the chiral unitary
approach in coupled channels. The isospin violation is introduced through the
use of different masses for the charged and neutral kaons, either in the
propagators of the pairs of mesons created in the $\chi_{c1}$ decay, or in the
propagators inside the $T$ matrix, constructed through the unitarization of the
scattering and transition amplitudes of pairs of pseudoscalar mesons. We find
that violating isospin inside the $T$ matrix makes the $\pi^0\eta \to
\pi^+\pi^-$ amplitude nonzero, which gives an important contribution and also
enhances the effect of the $K\bar{K}$ term. Also, we find that in the total
amplitude the most important effect is the isospin breaking inside the $T$
matrix, due to the constructive sum of $\pi^0\eta \to \pi^+\pi^-$ and $K\bar{K}
\to \pi^+ \pi^-$, which is essential to get a good agreement with the
experimental measurement of the mixing.
|
[
{
"created": "Wed, 9 Aug 2017 08:56:23 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Oct 2017 16:59:53 GMT",
"version": "v2"
}
] |
2017-11-03
|
[
[
"Bayar",
"M.",
""
],
[
"Debastiani",
"V. R.",
""
]
] |
We study the isospin breaking in the reactions $\chi_{c1} \to \pi^0 \pi^+ \pi^-$ and $\chi_{c1} \to \pi^0 \pi^0 \eta$ and its relation to the $a_0(980) - f_0(980)$ mixing, which was measured by the BESIII Collaboration. We show that the same theoretical model previously developed to study the $\chi_{c1} \to \eta \pi^+ \pi^-$ reaction (also measured by BESIII), and further explored in the predictions to the $\eta_{c} \to \eta \pi^+ \pi^-$, can be successfully employed in the present study. We assume that the $\chi_{c1}$ behaves as an $SU(3)$ singlet to find the weight in which trios of pseudoscalars are created, followed by the final state interaction of pairs of mesons to describe how the $a_0(980)$ and $f_0(980)$ are dynamically generated, using the chiral unitary approach in coupled channels. The isospin violation is introduced through the use of different masses for the charged and neutral kaons, either in the propagators of the pairs of mesons created in the $\chi_{c1}$ decay, or in the propagators inside the $T$ matrix, constructed through the unitarization of the scattering and transition amplitudes of pairs of pseudoscalar mesons. We find that violating isospin inside the $T$ matrix makes the $\pi^0\eta \to \pi^+\pi^-$ amplitude nonzero, which gives an important contribution and also enhances the effect of the $K\bar{K}$ term. Also, we find that in the total amplitude the most important effect is the isospin breaking inside the $T$ matrix, due to the constructive sum of $\pi^0\eta \to \pi^+\pi^-$ and $K\bar{K} \to \pi^+ \pi^-$, which is essential to get a good agreement with the experimental measurement of the mixing.
|
1306.5546
|
Hyejung St\"ockinger-Kim
|
C. Gnendiger, D. St\"ockinger, H. St\"ockinger-Kim
|
The electroweak contributions to (g-2)_\mu\ after the Higgs boson mass
measurement
|
11 pages, 5 figures. Slight update of numbers. Version to appear in
Phys.Rev.D
| null |
10.1103/PhysRevD.88.053005
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The Higgs boson mass used to be the only unknown input parameter of the
electroweak contributions to (g-2)_\mu\ in the Standard Model. It enters at the
two-loop level in diagrams with e.g. top loops, W- or Z-exchange. We
re-evaluate these contributions, providing analytic expressions and exact
numerical results for the Higgs boson mass recently measured at the LHC. Our
final result for the full Standard Model electroweak contributions is
(153.6\pm1.0)*10^{-11}, where the remaining theory error comes from unknown
three-loop contributions and hadronic uncertainties.
|
[
{
"created": "Mon, 24 Jun 2013 09:21:14 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Sep 2013 08:30:31 GMT",
"version": "v2"
}
] |
2013-09-18
|
[
[
"Gnendiger",
"C.",
""
],
[
"Stöckinger",
"D.",
""
],
[
"Stöckinger-Kim",
"H.",
""
]
] |
The Higgs boson mass used to be the only unknown input parameter of the electroweak contributions to (g-2)_\mu\ in the Standard Model. It enters at the two-loop level in diagrams with e.g. top loops, W- or Z-exchange. We re-evaluate these contributions, providing analytic expressions and exact numerical results for the Higgs boson mass recently measured at the LHC. Our final result for the full Standard Model electroweak contributions is (153.6\pm1.0)*10^{-11}, where the remaining theory error comes from unknown three-loop contributions and hadronic uncertainties.
|
1701.00812
|
Renata Jora
|
Amir H. Fariborz and Renata Jora
|
Electromagnetic axial anomaly in a generalized linear sigma model
|
15 pages; version to be published in Phys. Rev. D
|
Phys. Rev. D 95, 114001 (2017)
|
10.1103/PhysRevD.95.114001
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We construct the electromagnetic anomaly effective term for a generalized
linear sigma model with two chiral nonets, one with a quark-antiquark
structure, the other one with a four quark content. We compute in the leading
order of this framework the decays into two photons of six pseudoscalars:
$\pi_0(137)$, $\pi_0(1300)$, $\eta(547)$, $\eta(958)$, $\eta(1295)$ and
$\eta(1760)$. Our results agree well with the available experimental data.
|
[
{
"created": "Tue, 3 Jan 2017 20:25:48 GMT",
"version": "v1"
},
{
"created": "Thu, 27 Apr 2017 11:04:25 GMT",
"version": "v2"
}
] |
2017-06-07
|
[
[
"Fariborz",
"Amir H.",
""
],
[
"Jora",
"Renata",
""
]
] |
We construct the electromagnetic anomaly effective term for a generalized linear sigma model with two chiral nonets, one with a quark-antiquark structure, the other one with a four quark content. We compute in the leading order of this framework the decays into two photons of six pseudoscalars: $\pi_0(137)$, $\pi_0(1300)$, $\eta(547)$, $\eta(958)$, $\eta(1295)$ and $\eta(1760)$. Our results agree well with the available experimental data.
|
hep-ph/9408227
| null |
E.M. Henley and G.A. Miller
|
A Proposed Test of Charge Symmetry in $\Sigma$ Decay
|
6 pages, submitted to Physical Review D, Brief Reports, Report #
DOE/ER/40427-14-N94
|
Phys.Rev. D50 (1994) 7077-7078
|
10.1103/PhysRevD.50.7077
| null |
hep-ph
| null |
The semi-leptonic decays of $\Sigma^\pm$ offer a vehicle for observing charge
symmetry-breaking. The effect is expected to be about 6\%, enhanced due to the
replacement of two u quarks by d quarks. We propose that present experimental
data be improved to search for this effect.
|
[
{
"created": "Wed, 3 Aug 1994 20:09:58 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Henley",
"E. M.",
""
],
[
"Miller",
"G. A.",
""
]
] |
The semi-leptonic decays of $\Sigma^\pm$ offer a vehicle for observing charge symmetry-breaking. The effect is expected to be about 6\%, enhanced due to the replacement of two u quarks by d quarks. We propose that present experimental data be improved to search for this effect.
|
1510.00128
|
Andrzej Buras
|
Andrzej J. Buras
|
Kaon Theory News
|
Talk presented at HEP-EPS in Vienna, July 2015, 15 pages, 3 figures
| null | null | null |
hep-ph hep-ex hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
During the last fifteen years B_{s,d} decays, B_{s,d}^0-\bar B^0_{s,d}
mixings, CP-violating asymmetries S_{\psi K_S} and S_{\psi\phi} provided the
dominant information about the pattern of flavour violation within the SM and
its extensions. We emphasize that in the coming years K meson physics will
certainly strike back through the measurements of the branching ratios of
theoretically very clean decays K^+->pi^+\nu\bar\nu and K_L->\pi^0\nu\bar\nu
and improved calculations of the ratio epsilon'/epsilon=\epe. We summarize the
status of K^+->pi^+\nu\bar\nu and K_L->\pi^0\nu\bar\nu within the SM and
simplified NP models and update the picture of flavour violation in the
Littlest Higgs model with T-parity taking all available constraints into
account. But the highlight of this talk are new results on \epe from lattice
QCD and large N approach that give a strong indication for a new anomaly in
flavour physics, this time coming from K mesons. Indeed, \epe within the SM is
found to be significantly below the data of NA48 and KTeV collaborations.
Combining lattice results on the non-perturbative parameters B6 and B8 with the
assumption that the SM dynamics dominates the Delta I=1/2 rule a 3 sigma
anomaly in \epe emerges. Moreover, the recently derived upper bounds on B6 and
B8 from large N approach increase the confidence that the found anomaly could
be an important signal of NP at work. Of particular importance are the
correlations between K^+->pi^+\nu\bar\nu, K_L->\pi^0\nu\bar\nu and \epe. With
future precise measurements of K^+->pi^+\nu\bar\nu and K_L->\pi^0\nu\bar\nu and
improved calculations of \epe they will surely provide powerful tools for
selecting the favourite NP models. We illustrate this with the help of the LHT
model and simplified models in which NP in K\to\pi\nu\bar\nu and \epe is
governed by Z with flavour violating couplings or by a heavy Z'.
|
[
{
"created": "Thu, 1 Oct 2015 07:35:43 GMT",
"version": "v1"
}
] |
2015-10-02
|
[
[
"Buras",
"Andrzej J.",
""
]
] |
During the last fifteen years B_{s,d} decays, B_{s,d}^0-\bar B^0_{s,d} mixings, CP-violating asymmetries S_{\psi K_S} and S_{\psi\phi} provided the dominant information about the pattern of flavour violation within the SM and its extensions. We emphasize that in the coming years K meson physics will certainly strike back through the measurements of the branching ratios of theoretically very clean decays K^+->pi^+\nu\bar\nu and K_L->\pi^0\nu\bar\nu and improved calculations of the ratio epsilon'/epsilon=\epe. We summarize the status of K^+->pi^+\nu\bar\nu and K_L->\pi^0\nu\bar\nu within the SM and simplified NP models and update the picture of flavour violation in the Littlest Higgs model with T-parity taking all available constraints into account. But the highlight of this talk are new results on \epe from lattice QCD and large N approach that give a strong indication for a new anomaly in flavour physics, this time coming from K mesons. Indeed, \epe within the SM is found to be significantly below the data of NA48 and KTeV collaborations. Combining lattice results on the non-perturbative parameters B6 and B8 with the assumption that the SM dynamics dominates the Delta I=1/2 rule a 3 sigma anomaly in \epe emerges. Moreover, the recently derived upper bounds on B6 and B8 from large N approach increase the confidence that the found anomaly could be an important signal of NP at work. Of particular importance are the correlations between K^+->pi^+\nu\bar\nu, K_L->\pi^0\nu\bar\nu and \epe. With future precise measurements of K^+->pi^+\nu\bar\nu and K_L->\pi^0\nu\bar\nu and improved calculations of \epe they will surely provide powerful tools for selecting the favourite NP models. We illustrate this with the help of the LHT model and simplified models in which NP in K\to\pi\nu\bar\nu and \epe is governed by Z with flavour violating couplings or by a heavy Z'.
|
hep-ph/0308317
|
Igor Marfin
|
I. Marfin, V. Mossolov, T. Shishkina
|
Study of Quartic Boson Vertices at Photon Colliders in the Standard
Model and Beyond
|
Invited talk at the XXIII Physics in Collisions Conference (PIC03),
Zeuthen, Germany, June 2003, 3 pages, LaTeX, 4 eps figures. PSN FRAP11
| null | null | null |
hep-ph
| null |
The production of several vector bosons in $\gamma\gamma$-interactions is the
best place to search directly for any anomalous behavior of triple and quartic
couplings. A few anomalous quartic boson operators are considered in the paper.
A high precision of anomalous effects can be achieved by calculation of the
lowest order electroweak corrections: one-loop corrections, real photon and
$Z$-boson emission.
|
[
{
"created": "Fri, 29 Aug 2003 14:05:48 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Marfin",
"I.",
""
],
[
"Mossolov",
"V.",
""
],
[
"Shishkina",
"T.",
""
]
] |
The production of several vector bosons in $\gamma\gamma$-interactions is the best place to search directly for any anomalous behavior of triple and quartic couplings. A few anomalous quartic boson operators are considered in the paper. A high precision of anomalous effects can be achieved by calculation of the lowest order electroweak corrections: one-loop corrections, real photon and $Z$-boson emission.
|
1504.07415
|
Fanrong Xu
|
Fanrong Xu
|
Dark $Z$ Implication for Flavor Physics
|
13 pages, 3 figures; For V2 typo corrected, references added,
published in JHEP
|
JHEP 06 (2015) 170
|
10.1007/JHEP06(2015)170
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Dark $Z$/dark photon ($Z'$) is one candidate of dark force carrier, which
helps to interpret the properties of dark matter (DM). Other than traditional
studies of DM including direct detection, indirect detection and collider
simulation, in this work we take flavor physics as a complementary approach to
investigate the features of dark matter. We give an exact calculation of the
new type of penguin diagram induced by $Z'$ which further modifies the
well-known $X, Y, Z$ functions in penguin-box expansion. The measurement of
rare decays $B\to K^{(*)}\mu^+\mu^-$ and $B_s\to \mu^+\mu^-$ at LHC, together
with direct CP violation $\varepsilon'/\varepsilon$ in $K\to\pi \pi$ as well as
$K_L\to\mu^+\mu^-$, are used to determine the parameter space. The size of
coupling constant, however, is found to be $\mathcal{O}(1)$ which is much
weaker than the known constraints.
|
[
{
"created": "Tue, 28 Apr 2015 10:38:06 GMT",
"version": "v1"
},
{
"created": "Fri, 3 Jul 2015 01:12:50 GMT",
"version": "v2"
}
] |
2015-07-06
|
[
[
"Xu",
"Fanrong",
""
]
] |
Dark $Z$/dark photon ($Z'$) is one candidate of dark force carrier, which helps to interpret the properties of dark matter (DM). Other than traditional studies of DM including direct detection, indirect detection and collider simulation, in this work we take flavor physics as a complementary approach to investigate the features of dark matter. We give an exact calculation of the new type of penguin diagram induced by $Z'$ which further modifies the well-known $X, Y, Z$ functions in penguin-box expansion. The measurement of rare decays $B\to K^{(*)}\mu^+\mu^-$ and $B_s\to \mu^+\mu^-$ at LHC, together with direct CP violation $\varepsilon'/\varepsilon$ in $K\to\pi \pi$ as well as $K_L\to\mu^+\mu^-$, are used to determine the parameter space. The size of coupling constant, however, is found to be $\mathcal{O}(1)$ which is much weaker than the known constraints.
|
2003.05976
|
Michelangelo Mangano
|
Michelangelo Mangano
|
LHC at 10: the physics legacy
|
8 pages, 6 figures. Published in CERN Courier March/April 2020 p 40,
submitted to arXiv with permission
|
CERN Courier March/April 2020 p 40
| null |
CERN-TH-2020-030
|
hep-ph hep-ex hep-th
|
http://creativecommons.org/licenses/by/4.0/
|
Ten years into the LHC physics programme, I reflect on the vast amount of
extraordinary results that have emerged so far.
|
[
{
"created": "Thu, 12 Mar 2020 19:00:17 GMT",
"version": "v1"
}
] |
2020-03-16
|
[
[
"Mangano",
"Michelangelo",
""
]
] |
Ten years into the LHC physics programme, I reflect on the vast amount of extraordinary results that have emerged so far.
|
1209.3374
|
Ernest Ma
|
Ernest Ma (UC Riverside)
|
Self-Organizing Neutrino Mixing Matrix
|
7 pages, no figure (expanded discussion)
|
Phys. Rev. D86, 117301 (2012)
|
10.1103/PhysRevD.86.117301
|
UCRHEP-T523 (September 2012)
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A new and novel idea for a predictive neutrino mass matrix is presented,
using the non-Abelian discrete symmetry A(4) and the seesaw mechanism with only
two heavy neutral fermion singlets. Given the components of the one necessarily
massless neutrino eigenstate, the other two massive states are automatically
generated. A realistic example is discussed with predictions of a normal
hierarchy of neutrino masses and maximal CP violation.
|
[
{
"created": "Sat, 15 Sep 2012 08:58:27 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Sep 2012 15:11:05 GMT",
"version": "v2"
}
] |
2015-06-11
|
[
[
"Ma",
"Ernest",
"",
"UC Riverside"
]
] |
A new and novel idea for a predictive neutrino mass matrix is presented, using the non-Abelian discrete symmetry A(4) and the seesaw mechanism with only two heavy neutral fermion singlets. Given the components of the one necessarily massless neutrino eigenstate, the other two massive states are automatically generated. A realistic example is discussed with predictions of a normal hierarchy of neutrino masses and maximal CP violation.
|
hep-ph/0408181
|
Kingman Cheung
|
Kingman Cheung (NTHU)
|
Summary Report for the $e^- e^-$ session in LCWS 2004
|
4 pages and 1 figures. Plenary talk given at the International
Conference on Linear Colliders, LCWS04, 19-23 April 2004, Paris, France
| null | null | null |
hep-ph
| null |
In this talk, I summarize the activities in the $e^- e^-$ session. The
consensus is that if the next generation $e^+ e^-$ linear collider wants to
include an $e^- e^-$ option, the planning has to include it as early as
possible. By doing so the extra cost would be only a small fraction of the
total, and of course the physics potential would be very rewarding.
|
[
{
"created": "Tue, 17 Aug 2004 07:27:34 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Cheung",
"Kingman",
"",
"NTHU"
]
] |
In this talk, I summarize the activities in the $e^- e^-$ session. The consensus is that if the next generation $e^+ e^-$ linear collider wants to include an $e^- e^-$ option, the planning has to include it as early as possible. By doing so the extra cost would be only a small fraction of the total, and of course the physics potential would be very rewarding.
|
hep-ph/0101334
|
Koichi Yoshioka
|
N. Haba, J. Sato, M. Tanimoto and K. Yoshioka
|
Possible Flavor Mixing Structures of Lepton Mass Matrices
|
21 pages
|
Phys.Rev. D64 (2001) 113016
|
10.1103/PhysRevD.64.113016
| null |
hep-ph
| null |
To search for possible textures of lepton mass matrices, we systematically
examine flavor mixing structures which can lead to large lepton mixing angles.
We find out 37 mixing patterns are consistent with experimental data, taking
into account phase factors in the mixing matrices. Only six of the patterns can
explain the observed data without any tuning of parameters, while the others
need particular choices for the phase values. It is found that these six mixing
patterns are those predicted by the models which have been proposed to account
for fermion mass hierarchies. On the other hand, the others may give new flavor
mixing structures of lepton mass matrices and therefore new possibilities of
model construction.
|
[
{
"created": "Tue, 30 Jan 2001 14:24:52 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Feb 2001 11:08:43 GMT",
"version": "v2"
},
{
"created": "Mon, 7 May 2001 07:32:49 GMT",
"version": "v3"
},
{
"created": "Fri, 19 Oct 2001 06:06:02 GMT",
"version": "v4"
}
] |
2009-11-07
|
[
[
"Haba",
"N.",
""
],
[
"Sato",
"J.",
""
],
[
"Tanimoto",
"M.",
""
],
[
"Yoshioka",
"K.",
""
]
] |
To search for possible textures of lepton mass matrices, we systematically examine flavor mixing structures which can lead to large lepton mixing angles. We find out 37 mixing patterns are consistent with experimental data, taking into account phase factors in the mixing matrices. Only six of the patterns can explain the observed data without any tuning of parameters, while the others need particular choices for the phase values. It is found that these six mixing patterns are those predicted by the models which have been proposed to account for fermion mass hierarchies. On the other hand, the others may give new flavor mixing structures of lepton mass matrices and therefore new possibilities of model construction.
|
hep-ph/9401294
|
Adrian Signer
|
Zoltan Kunszt, Adrian Signer and Zoltan Trocsanyi
|
Singular terms of helicity amplitudes at one-loop in QCD and the soft
limit of the cross sections of multi-parton processes
|
Latex,13 pages, ETH-TH/94-3
|
Nucl.Phys. B420 (1994) 550-564
|
10.1016/0550-3213(94)90077-9
| null |
hep-ph
| null |
We describe a general method that enables us to obtain all the singular terms
of helicity amplitudes of n-parton processes at one loop. The algorithm uses
helicity amplitudes at tree level and simple color algebra.
We illustrate the method by calculating the singular part of the one loop
helicity amplitudes of all $ 2\to 3$ parton subprocesses. The results are used
to derive the soft gluon limit of the cross sections of all $2\to 4$ parton
scattering subprocesses which provide a useful initial condition for the
angular ordering approximation to coherent multiple soft gluon emission,
incorporated in existing Monte Carlo simulation programs.
|
[
{
"created": "Thu, 20 Jan 1994 16:18:52 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Kunszt",
"Zoltan",
""
],
[
"Signer",
"Adrian",
""
],
[
"Trocsanyi",
"Zoltan",
""
]
] |
We describe a general method that enables us to obtain all the singular terms of helicity amplitudes of n-parton processes at one loop. The algorithm uses helicity amplitudes at tree level and simple color algebra. We illustrate the method by calculating the singular part of the one loop helicity amplitudes of all $ 2\to 3$ parton subprocesses. The results are used to derive the soft gluon limit of the cross sections of all $2\to 4$ parton scattering subprocesses which provide a useful initial condition for the angular ordering approximation to coherent multiple soft gluon emission, incorporated in existing Monte Carlo simulation programs.
|
1007.1497
|
Wataru Sakamoto
|
Masako Hayashi, Tomohiro Inagaki, Wataru Sakamoto
|
Phase Structure of a Four- and Eight-Fermion Interaction Model at Finite
Temperature and Chemical Potential in Arbitrary Dimensions
|
20 pages, 26 figures; revised argument and added reference for
section 5
|
Int.J.Mod.Phys.A25:4757-4774,2010
|
10.1142/S0217751X10050627
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The phase structure of a four- and eight-fermion interaction model is
investigated at finite temperature and chemical potential in arbitrary
space-time dimensions, $2\leq D<4$. The effective potential and the gap
equation are calculated in the leading order of the 1/N expansion. If the first
order phase transition takes place, the phase boundary dividing the symmetric
and the broken phase is modified by the eight-fermion interaction.
|
[
{
"created": "Fri, 9 Jul 2010 02:28:25 GMT",
"version": "v1"
},
{
"created": "Tue, 27 Jul 2010 05:48:53 GMT",
"version": "v2"
}
] |
2011-03-14
|
[
[
"Hayashi",
"Masako",
""
],
[
"Inagaki",
"Tomohiro",
""
],
[
"Sakamoto",
"Wataru",
""
]
] |
The phase structure of a four- and eight-fermion interaction model is investigated at finite temperature and chemical potential in arbitrary space-time dimensions, $2\leq D<4$. The effective potential and the gap equation are calculated in the leading order of the 1/N expansion. If the first order phase transition takes place, the phase boundary dividing the symmetric and the broken phase is modified by the eight-fermion interaction.
|
1409.6517
|
Juan Jose Sanz-Cillero
|
J.J. Sanz-Cillero
|
Electroweak chiral Lagrangians and the Higgs properties at the one-loop
level
|
6 pages, 2 eps figures. Proceedings of the 7th Edition of the
International Workshop on Quantum Chromodynamics -QCD@Work: Interantional
Workshop on QCD, Theory and Experiment- (16-19 June 2014, Giovinazzo, Italy)
| null |
10.1051/epjconf/20148000053
|
IFT-UAM/CSIC-14-096, FTUAM-14-37
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In these proceedings we explore the use of (non-linear) electroweak chiral
Lagrangians for the description of possible beyond the Standard Model strong
dynamics in the electroweak sector. Experimentally one observes an approximate
electroweak symmetry breaking pattern $SU(2)_L\times SU(2)_R/SU(2)_{L+R}$.
Quantum Chromodynamics shows a similar chiral structure and, in spite of the
differences (in the electroweak theory $SU(2)_L\times U(1)_Y$ is gauged), it
has served for years as a guide for this type of studies. Examples of one-loop
computations in the low-energy effective theory and the theory including the
first vector and axial-vector resonances are provided, yielding, respectively,
predictions for $\gamma\gamma\to Z_LZ_L,W^+_LW^-_L$ and the oblique parameters
$S$ and $T$.
|
[
{
"created": "Tue, 23 Sep 2014 12:48:37 GMT",
"version": "v1"
}
] |
2015-06-23
|
[
[
"Sanz-Cillero",
"J. J.",
""
]
] |
In these proceedings we explore the use of (non-linear) electroweak chiral Lagrangians for the description of possible beyond the Standard Model strong dynamics in the electroweak sector. Experimentally one observes an approximate electroweak symmetry breaking pattern $SU(2)_L\times SU(2)_R/SU(2)_{L+R}$. Quantum Chromodynamics shows a similar chiral structure and, in spite of the differences (in the electroweak theory $SU(2)_L\times U(1)_Y$ is gauged), it has served for years as a guide for this type of studies. Examples of one-loop computations in the low-energy effective theory and the theory including the first vector and axial-vector resonances are provided, yielding, respectively, predictions for $\gamma\gamma\to Z_LZ_L,W^+_LW^-_L$ and the oblique parameters $S$ and $T$.
|
1812.07187
|
Murat Koksal
|
V. Ari, E. Gurkanli, A. A. Billur and M. Koksal
|
Model independent study for the anomalous quartic $WW\gamma\gamma$
couplings at Future Electron-Proton Colliders
|
28 Pages, 15 Figures and 7 Tables
| null |
10.1016/j.nuclphysb.2020.115102
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The Large Hadron Electron Collider and the Future Circular Collider-hadron
electron with high center-of-mass energy and luminosity allow to better
understand the Standard Model and to examine new physics beyond the Standard
Model in the electroweak sector. Multi-boson processes permit for a measurement
of the gauge boson self-interactions of the Standard Model that can be used to
determine the anomalous gauge boson couplings. For this purpose, we present a
study of the process $ep \rightarrow \nu_{e} \gamma \gamma j$ at the Large
Hadron Electron Collider with center-of-mass energies of 1.30, 1.98 TeV and at
the Future Circular Collider-hadron electron with center-of-mass energies of
7.07, 10 TeV to interpret the anomalous quartic $WW\gamma\gamma$ gauge
couplings using a model independent way in the framework of effective field
theory. We obtain the sensitivity limits at $95\%$ Confidence Level on 13
different anomalous couplings arising from dimension-8 operators. The best
limit in $f_{Mi}/\Lambda^{4}$ ($i=0,1,2,3,4,5,7$) parameters is obtained for
$f_{M2}/\Lambda^{4}$ parameter while the best sensitivity derived on
$f_{Ti}/\Lambda^{4}$ ($i=0,1,2,5,6,7$) parameters is obtained for
$f_{T5}/\Lambda^{4}$. In addition, this study is the first report on the
anomalous quartic couplings determined by effective Lagrangians at $ep$
colliders.
|
[
{
"created": "Tue, 18 Dec 2018 06:14:57 GMT",
"version": "v1"
},
{
"created": "Sat, 8 Aug 2020 11:25:17 GMT",
"version": "v2"
}
] |
2020-08-11
|
[
[
"Ari",
"V.",
""
],
[
"Gurkanli",
"E.",
""
],
[
"Billur",
"A. A.",
""
],
[
"Koksal",
"M.",
""
]
] |
The Large Hadron Electron Collider and the Future Circular Collider-hadron electron with high center-of-mass energy and luminosity allow to better understand the Standard Model and to examine new physics beyond the Standard Model in the electroweak sector. Multi-boson processes permit for a measurement of the gauge boson self-interactions of the Standard Model that can be used to determine the anomalous gauge boson couplings. For this purpose, we present a study of the process $ep \rightarrow \nu_{e} \gamma \gamma j$ at the Large Hadron Electron Collider with center-of-mass energies of 1.30, 1.98 TeV and at the Future Circular Collider-hadron electron with center-of-mass energies of 7.07, 10 TeV to interpret the anomalous quartic $WW\gamma\gamma$ gauge couplings using a model independent way in the framework of effective field theory. We obtain the sensitivity limits at $95\%$ Confidence Level on 13 different anomalous couplings arising from dimension-8 operators. The best limit in $f_{Mi}/\Lambda^{4}$ ($i=0,1,2,3,4,5,7$) parameters is obtained for $f_{M2}/\Lambda^{4}$ parameter while the best sensitivity derived on $f_{Ti}/\Lambda^{4}$ ($i=0,1,2,5,6,7$) parameters is obtained for $f_{T5}/\Lambda^{4}$. In addition, this study is the first report on the anomalous quartic couplings determined by effective Lagrangians at $ep$ colliders.
|
2209.03538
|
M. Gabriel Santiago
|
Yuri V. Kovchegov, M. Gabriel Santiago
|
T-odd Leading-Twist Quark TMDs at Small $x$
|
50 pages, 5 figures
| null |
10.1007/JHEP11(2022)098
| null |
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the small-$x$ asymptotics of the flavor non-singlet T-odd
leading-twist quark transverse momentum dependent parton distributions (TMDs),
the Sivers and Boer-Mulders functions. While the leading eikonal small-$x$
asymptotics of the quark Sivers function is given by the spin-dependent
odderon, we are interested in revisiting the sub-eikonal correction considered
by us earlier. We first simplify the expressions for both TMDs at small Bjorken
$x$ and then construct small-$x$ evolution equations for the resulting
operators in the large-$N_c$ limit, with $N_c$ the number of quark colors. For
both TMDs, the evolution equations resum all powers of the double-logarithmic
parameter $\alpha_s \, \ln^2 (1/x)$, where $\alpha_s$ is the strong coupling
constant, which is assumed to be small. Solving these evolution equations
numerically (for the Sivers function) and analytically (for the Boer-Mulders
function) we arrive at the following leading small-$x$ asymptotics of these
TMDs at large $N_c$: \begin{align} f_{1 \: T}^{\perp \: NS} (x \ll 1 ,k_T^2) &
= C_O (x, k_T^2) \, \frac{1}{x} + C_1 (x, k_T^2) \, \left( \frac{1}{x}
\right)^{3.4 \, \sqrt{\frac{\alpha_s \, N_c}{4 \pi}}} , \notag \\ h_1^{\perp \,
\textrm{NS}} (x \ll 1, k_T^2) & = C (x, k_T^2) \left( \frac{1}{x} \right)^{-1}.
\notag \end{align} The functions $C_O (x, k_T^2)$, $C_1 (x, k_T^2)$, and $C (x,
k_T^2)$ can be readily obtained in our formalism: they are mildly $x$-dependent
and do not strongly affect the power-of-$x$ asymptotics shown above. The
function $C_O$, along with the $1/x$ factor, arises from the odderon exchange.
For the sub-eikonal contribution to the quark Sivers function (the term with
$C_1$), our result shown above supersedes the one obtained in our previous work
due to the new contributions identified recently.
|
[
{
"created": "Thu, 8 Sep 2022 02:36:54 GMT",
"version": "v1"
}
] |
2022-11-30
|
[
[
"Kovchegov",
"Yuri V.",
""
],
[
"Santiago",
"M. Gabriel",
""
]
] |
We study the small-$x$ asymptotics of the flavor non-singlet T-odd leading-twist quark transverse momentum dependent parton distributions (TMDs), the Sivers and Boer-Mulders functions. While the leading eikonal small-$x$ asymptotics of the quark Sivers function is given by the spin-dependent odderon, we are interested in revisiting the sub-eikonal correction considered by us earlier. We first simplify the expressions for both TMDs at small Bjorken $x$ and then construct small-$x$ evolution equations for the resulting operators in the large-$N_c$ limit, with $N_c$ the number of quark colors. For both TMDs, the evolution equations resum all powers of the double-logarithmic parameter $\alpha_s \, \ln^2 (1/x)$, where $\alpha_s$ is the strong coupling constant, which is assumed to be small. Solving these evolution equations numerically (for the Sivers function) and analytically (for the Boer-Mulders function) we arrive at the following leading small-$x$ asymptotics of these TMDs at large $N_c$: \begin{align} f_{1 \: T}^{\perp \: NS} (x \ll 1 ,k_T^2) & = C_O (x, k_T^2) \, \frac{1}{x} + C_1 (x, k_T^2) \, \left( \frac{1}{x} \right)^{3.4 \, \sqrt{\frac{\alpha_s \, N_c}{4 \pi}}} , \notag \\ h_1^{\perp \, \textrm{NS}} (x \ll 1, k_T^2) & = C (x, k_T^2) \left( \frac{1}{x} \right)^{-1}. \notag \end{align} The functions $C_O (x, k_T^2)$, $C_1 (x, k_T^2)$, and $C (x, k_T^2)$ can be readily obtained in our formalism: they are mildly $x$-dependent and do not strongly affect the power-of-$x$ asymptotics shown above. The function $C_O$, along with the $1/x$ factor, arises from the odderon exchange. For the sub-eikonal contribution to the quark Sivers function (the term with $C_1$), our result shown above supersedes the one obtained in our previous work due to the new contributions identified recently.
|
hep-ph/0404238
|
Otto Kong
|
Otto C.W. Kong (Nat'l Central U., Taiwan)
|
On Extended Electroweak Symmetries
|
1+8 pages of latex with ws-procs9x6.cls; talk presented at Coral
Gables Conference 2003
|
Int.J.Mod.Phys. A20 (2005) 1295-1302
|
10.1142/S0217751X05024195
|
NCU-HEP-k016
|
hep-ph
| null |
We discuss extensions of the Standard Model through extending the electroweak
gauge symmetry. An extended electroweak symmetry requires a list of extra
fermionic and scalar states. The former is necessary to maintain cancellation
of gauge anomalies, and largely fixed by the symmetry embedding itself. The
latter is usually considered quite arbitrary, so long as a vacuum structure
admitting the symmetry breaking is allowed. Anomaly cancellation may be used to
link the three families of quarks and leptons together, given a perspective on
flavor physics. It is illustrated lately that the kind of models may also have
the so-called little Higgs mechanism incorporated. This more or less fixes the
scalar sector and take care of the hierarchy problem, making such models of
extended electroweak symmetries quite appealing candidates as TeV scale
effective field theories.
|
[
{
"created": "Tue, 27 Apr 2004 12:56:11 GMT",
"version": "v1"
}
] |
2009-11-10
|
[
[
"Kong",
"Otto C. W.",
"",
"Nat'l Central U., Taiwan"
]
] |
We discuss extensions of the Standard Model through extending the electroweak gauge symmetry. An extended electroweak symmetry requires a list of extra fermionic and scalar states. The former is necessary to maintain cancellation of gauge anomalies, and largely fixed by the symmetry embedding itself. The latter is usually considered quite arbitrary, so long as a vacuum structure admitting the symmetry breaking is allowed. Anomaly cancellation may be used to link the three families of quarks and leptons together, given a perspective on flavor physics. It is illustrated lately that the kind of models may also have the so-called little Higgs mechanism incorporated. This more or less fixes the scalar sector and take care of the hierarchy problem, making such models of extended electroweak symmetries quite appealing candidates as TeV scale effective field theories.
|
1903.05116
|
Joachim Brod
|
Joachim Brod, Martin Gorbahn
|
The Z Penguin in Generic Extensions of the Standard Model
|
28 pages, 2 figures; improved discussion, version as published in
JHEP
|
JHEP 1909 (2019) 027
|
10.1007/JHEP09(2019)027
| null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
Precision flavour observables play an important role in the interpretation of
results at the LHC in terms of models of new physics. We present the result for
the one-loop Z penguin in generic extensions of the standard model which
exhibit exact perturbative unitarity. We use Slavnov-Taylor identities to study
the implications of unitarity on the renormalisation of the Z penguin, and
derive a manifestly finite result that depends on a reduced set of physical
couplings.
|
[
{
"created": "Tue, 12 Mar 2019 18:04:02 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Apr 2021 21:45:14 GMT",
"version": "v2"
}
] |
2021-04-19
|
[
[
"Brod",
"Joachim",
""
],
[
"Gorbahn",
"Martin",
""
]
] |
Precision flavour observables play an important role in the interpretation of results at the LHC in terms of models of new physics. We present the result for the one-loop Z penguin in generic extensions of the standard model which exhibit exact perturbative unitarity. We use Slavnov-Taylor identities to study the implications of unitarity on the renormalisation of the Z penguin, and derive a manifestly finite result that depends on a reduced set of physical couplings.
|
hep-ph/9605347
|
Felice Pisano
|
F. Pisano (IFT - S.Paulo - Brazil), J.A. Silva-Sobrinho (IFT -S.Paulo
- Brazil) and M.D. Tonasse (UERJ - Rio de Janeiro - Brazil)
|
Neutrinos and Electromagnetic Gauge Invariance
|
10 pages, Revtex 3.0, no figures
|
Phys.Lett. B388 (1996) 338-345
|
10.1016/S0370-2693(96)01250-6
|
IFT-P.005/96
|
hep-ph
| null |
It is discussed a recently proposed connection among U(1)$_{\rm em}$
electromagnetic gauge invariance and the nature of the neutrino mass terms in
the framework of $\mbox {SU(3)}_C\otimes G_W \otimes {\mbox U(1)}_N$, $G_W$ =
SU(3)$_L$, extensions of the Standard Model. The impossibility of that
connection, also in the extended case $G_W $ = SU(4)$_L$, is demonstrated.
|
[
{
"created": "Fri, 17 May 1996 20:12:58 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Pisano",
"F.",
"",
"IFT - S.Paulo - Brazil"
],
[
"Silva-Sobrinho",
"J. A.",
"",
"IFT -S.Paulo\n - Brazil"
],
[
"Tonasse",
"M. D.",
"",
"UERJ - Rio de Janeiro - Brazil"
]
] |
It is discussed a recently proposed connection among U(1)$_{\rm em}$ electromagnetic gauge invariance and the nature of the neutrino mass terms in the framework of $\mbox {SU(3)}_C\otimes G_W \otimes {\mbox U(1)}_N$, $G_W$ = SU(3)$_L$, extensions of the Standard Model. The impossibility of that connection, also in the extended case $G_W $ = SU(4)$_L$, is demonstrated.
|
hep-ph/9806390
|
Christian Weiss
|
M.V. Polyakov and C. Weiss
|
Two-pion light-cone distribution amplitudes from the instanton vacuum
|
13 pages, LaTeX, 4 figures included using epsf
|
Phys.Rev.D59:091502,1999
|
10.1103/PhysRevD.59.091502
|
RUB-TPII-7/98
|
hep-ph
| null |
We calculate the two-pion light-cone distribution amplitudes in the effective
low-energy theory based on the instanton vacuum. These generalized distribution
amplitudes describe the soft (non-perturbative) part of the process
$\gamma^*\gamma \to \pi\pi$ in the region where the c.m. energy is much smaller
than the photon virtuality. They can also be used in the analysis of exclusive
processes such as $\gamma^* p \to p + 2\pi, 3\pi$ etc.
|
[
{
"created": "Tue, 16 Jun 1998 23:32:36 GMT",
"version": "v1"
}
] |
2009-12-30
|
[
[
"Polyakov",
"M. V.",
""
],
[
"Weiss",
"C.",
""
]
] |
We calculate the two-pion light-cone distribution amplitudes in the effective low-energy theory based on the instanton vacuum. These generalized distribution amplitudes describe the soft (non-perturbative) part of the process $\gamma^*\gamma \to \pi\pi$ in the region where the c.m. energy is much smaller than the photon virtuality. They can also be used in the analysis of exclusive processes such as $\gamma^* p \to p + 2\pi, 3\pi$ etc.
|
0912.0351
|
Fu-Guang Cao
|
H. Chen, F.-G. Cao, A. I. Signal
|
Strange sea distributions of the nucleon
|
version published in J. Phys. G, 14 pages, 3 figures
|
J.Phys.G37:105006,2010
|
10.1088/0954-3899/37/10/105006
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The strange and antistrange quark distributions of the nucleon are less
constrained by experimental data than the non-strange quark sea. The
combination of light quark sea distributions,
$\Delta(x)=\dbar(x)+\ubar(x)-s(x)-\sbar(x)$, originates mainly from
non-perturbative processes and can be calculated using non-perturbative models
of the nucleon. We have calculated $\Delta(x)$ using the meson cloud model,
which, when combined with the relatively well known non-strange light antiquark
distributions obtained from global analysis of available experimental data,
enables us to make new estimates of the total strange sea distributions of the
nucleon and the strange sea suppression factor.
|
[
{
"created": "Wed, 2 Dec 2009 07:29:20 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Aug 2010 23:16:37 GMT",
"version": "v2"
}
] |
2010-08-26
|
[
[
"Chen",
"H.",
""
],
[
"Cao",
"F. -G.",
""
],
[
"Signal",
"A. I.",
""
]
] |
The strange and antistrange quark distributions of the nucleon are less constrained by experimental data than the non-strange quark sea. The combination of light quark sea distributions, $\Delta(x)=\dbar(x)+\ubar(x)-s(x)-\sbar(x)$, originates mainly from non-perturbative processes and can be calculated using non-perturbative models of the nucleon. We have calculated $\Delta(x)$ using the meson cloud model, which, when combined with the relatively well known non-strange light antiquark distributions obtained from global analysis of available experimental data, enables us to make new estimates of the total strange sea distributions of the nucleon and the strange sea suppression factor.
|
1411.5584
|
Qian Wang
|
Feng-Kun Guo, Christoph Hanhart, Qian Wang, Qiang Zhao
|
Could the near-threshold $XYZ$ states be simply kinematic effects?
|
Accepted by Phys. Rev. D as a rapid communication
|
Phys. Rev. D 91, 051504 (2015)
|
10.1103/PhysRevD.91.051504
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We demonstrate that the spectacular structures discovered recently in various
experiments and named as $X$, $Y$ and $Z$ states cannot be purely kinematic
effects. Their existence necessarily calls for nearby poles in the $S$--matrix
and they therefore qualify as states. We propose a way to distinguishing
kinematic cusp effects from genuine $S$--matrix poles: the kinematic threshold
cusp cannot produce a narrow peak in the invariant mass distribution in the
elastic channel in contrast with a genuine $S$--matrix pole.
|
[
{
"created": "Thu, 20 Nov 2014 15:58:06 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Mar 2015 19:34:59 GMT",
"version": "v2"
}
] |
2015-04-01
|
[
[
"Guo",
"Feng-Kun",
""
],
[
"Hanhart",
"Christoph",
""
],
[
"Wang",
"Qian",
""
],
[
"Zhao",
"Qiang",
""
]
] |
We demonstrate that the spectacular structures discovered recently in various experiments and named as $X$, $Y$ and $Z$ states cannot be purely kinematic effects. Their existence necessarily calls for nearby poles in the $S$--matrix and they therefore qualify as states. We propose a way to distinguishing kinematic cusp effects from genuine $S$--matrix poles: the kinematic threshold cusp cannot produce a narrow peak in the invariant mass distribution in the elastic channel in contrast with a genuine $S$--matrix pole.
|
hep-ph/0301005
|
Jiri Novotny
|
M. Kolesar, J. Novotny
|
The eta->pi^0 pi^0 gamma gamma decay in generalized chiral perturbation
theory
|
7 pages, 6 figures, Talk presented at Int. Conf. Hadron Structure
'02, Herlany, Slovakia, September 22-27, 2002
| null | null | null |
hep-ph
| null |
Calculations of eta->pi^0 pi^0 gamma gamma decay in generalized chiral
perturbation theory are presented. Tree level and some of next-to-leading
corrections are involved. Sensitivity to the deviations from the standard
chiral perturbation theory is discussed.
|
[
{
"created": "Thu, 2 Jan 2003 14:47:38 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Kolesar",
"M.",
""
],
[
"Novotny",
"J.",
""
]
] |
Calculations of eta->pi^0 pi^0 gamma gamma decay in generalized chiral perturbation theory are presented. Tree level and some of next-to-leading corrections are involved. Sensitivity to the deviations from the standard chiral perturbation theory is discussed.
|
hep-ph/0607193
|
Bruno Machet
|
Quentin Duret (LPTHE), Bruno Machet (LPTHE)
|
The Cabibbo angle : an algebraic calculation
|
The Cabibbo angle can be positive or negative, which was overlooked
in the first version. Minor addenda
| null | null | null |
hep-ph hep-th
| null |
We show that the Cabibbo angle theta\_c satisfies the relation tan(2
theta\_c)=-+/- 1/2 when universality for diagonal neutral currents of mass
eigenstates is satisfied at the same level of accuracy as the absence of their
off-diagonal counterparts. The predicted value is cos theta\_c \approx 0.9732,
only 7/10000 away from experimental results. No mass ratio appears in the
calculation. theta\_c occurs a priori for both quark species, and, showing that
one recovers the standard dependence of leptonic and semi-leptonic decays of
pseudoscalar mesons, we advocate, like for neutrinos and charged leptons, for a
symmetrical treatment of u and d-type quarks.
|
[
{
"created": "Tue, 18 Jul 2006 05:15:55 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Sep 2006 08:33:30 GMT",
"version": "v2"
}
] |
2007-05-23
|
[
[
"Duret",
"Quentin",
"",
"LPTHE"
],
[
"Machet",
"Bruno",
"",
"LPTHE"
]
] |
We show that the Cabibbo angle theta\_c satisfies the relation tan(2 theta\_c)=-+/- 1/2 when universality for diagonal neutral currents of mass eigenstates is satisfied at the same level of accuracy as the absence of their off-diagonal counterparts. The predicted value is cos theta\_c \approx 0.9732, only 7/10000 away from experimental results. No mass ratio appears in the calculation. theta\_c occurs a priori for both quark species, and, showing that one recovers the standard dependence of leptonic and semi-leptonic decays of pseudoscalar mesons, we advocate, like for neutrinos and charged leptons, for a symmetrical treatment of u and d-type quarks.
|
hep-ph/9906305
|
Andre Peshier
|
A. Peshier, B. Kampfer, G. Soff
|
Thermodynamics of Deconfined Matter at Finite Chemical Potential in a
Quasiparticle Description
|
4 pages REVTEX, 3 eps figures
| null | null | null |
hep-ph
| null |
An effective quasiparticle description of the thermodynamics of deconfined
matter, compatible with both finite-temperature lattice data and the
perturbative limit, is generalized to finite chemical potential. Within this
approach, the available 4-flavor lattice equation of state is extended to
finite baryon density, and implications for cold, charge-neutral deconfined
matter in beta-equilibrium in compact stars are considered.
|
[
{
"created": "Wed, 9 Jun 1999 14:42:47 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Peshier",
"A.",
""
],
[
"Kampfer",
"B.",
""
],
[
"Soff",
"G.",
""
]
] |
An effective quasiparticle description of the thermodynamics of deconfined matter, compatible with both finite-temperature lattice data and the perturbative limit, is generalized to finite chemical potential. Within this approach, the available 4-flavor lattice equation of state is extended to finite baryon density, and implications for cold, charge-neutral deconfined matter in beta-equilibrium in compact stars are considered.
|
1601.04954
|
Xiao-Fang Han
|
Xiao-Fang Han, Lei Wang, Jin Min Yang
|
An extension of two-Higgs-doublet model and the excesses of 750 GeV
diphoton, muon g-2 and $h\to\mu\tau$
|
18 pages, 3 figures and references added
| null |
10.1016/j.physletb.2016.04.036
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this paper we simultaneously explain the excesses of the 750 GeV diphoton,
muon g-2 and $h\to \mu\tau$ in an extension of the two-Higgs-doublet model
(2HDM) with additional vector-like fermions and a CP-odd scalar singlet ($P$)
which is identified as the 750 GeV resonance. This 750 GeV resonance has a
mixing with the CP-odd scalar ($A$) in 2HDM, which leads to a coupling between
$P$ and the SM particles as well as a coupling between $A$ and the vector-like
fermions. Such a mixing and couplings are strongly constrained by
$\tau\to\mu\gamma$, muon g-2 and the 750 GeV diphoton data. We scan over the
parameter space and find that such an extension can simultaneously account for
the observed excesses of 750 GeV diphoton, muon g-2 and $h\to \mu\tau$. The 750
GeV resonance decays in exotic modes, such as $P\to hA$, $P\to HZ$, $P\to HA$
and $P\to W^\pm H^\mp$, and its width can be dozens of GeV and is sensitive to
the mixing angle.
|
[
{
"created": "Tue, 19 Jan 2016 15:32:18 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Jan 2016 15:24:19 GMT",
"version": "v2"
}
] |
2016-05-25
|
[
[
"Han",
"Xiao-Fang",
""
],
[
"Wang",
"Lei",
""
],
[
"Yang",
"Jin Min",
""
]
] |
In this paper we simultaneously explain the excesses of the 750 GeV diphoton, muon g-2 and $h\to \mu\tau$ in an extension of the two-Higgs-doublet model (2HDM) with additional vector-like fermions and a CP-odd scalar singlet ($P$) which is identified as the 750 GeV resonance. This 750 GeV resonance has a mixing with the CP-odd scalar ($A$) in 2HDM, which leads to a coupling between $P$ and the SM particles as well as a coupling between $A$ and the vector-like fermions. Such a mixing and couplings are strongly constrained by $\tau\to\mu\gamma$, muon g-2 and the 750 GeV diphoton data. We scan over the parameter space and find that such an extension can simultaneously account for the observed excesses of 750 GeV diphoton, muon g-2 and $h\to \mu\tau$. The 750 GeV resonance decays in exotic modes, such as $P\to hA$, $P\to HZ$, $P\to HA$ and $P\to W^\pm H^\mp$, and its width can be dozens of GeV and is sensitive to the mixing angle.
|
0707.1723
|
Pomita Ghoshal
|
Raj Gandhi, Pomita Ghoshal, Srubabati Goswami, Poonam Mehta, S Uma
Sankar, Shashank Shalgar
|
Mass Hierarchy Determination via future Atmospheric Neutrino Detectors
|
36 pages, 13 figures, revised version accepted in Physical Review D
|
Phys.Rev.D76:073012,2007
|
10.1103/PhysRevD.76.073012
| null |
hep-ph hep-ex
| null |
We study the problem of determination of the sign of Delta m^2_{31}, or the
neutrino mass hierarchy, through observations of atmospheric neutrinos in
future detectors. We consider two proposed detector types :
(a) Megaton sized water Cerenkov detectors, which can measure the survival
rates of nu_\mu + \bar{\nu}_\mu and nu_e + \bar{\nu}_e and (b) 100 kton sized
magnetized iron detectors, which can measure the survival rates of \nu_\mu and
\bar{\nu}_\mu. For energies and path-lengths relevant to atmospheric neutrinos,
these rates obtain significant matter contributions from P_{\mu e}, P_{\mu \mu}
and P_{ee}, leading to an appreciable sensitivity to the hierarchy. We do a
binned \chi^2 analysis of simulated data in these two types of detectors which
includes the effect of smearing in neutrino energy and direction and
incorporates detector efficiencies and relevant statistical, theoretical and
systematic errors. We also marginalize the \chi^2 over the allowed ranges of
neutrino parameters in order to accurately account for their uncertainties.
Finally, we compare the performance of both types of detectors vis a vis the
hierarchy determination.
|
[
{
"created": "Thu, 12 Jul 2007 00:32:01 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Sep 2007 13:02:31 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Gandhi",
"Raj",
""
],
[
"Ghoshal",
"Pomita",
""
],
[
"Goswami",
"Srubabati",
""
],
[
"Mehta",
"Poonam",
""
],
[
"Sankar",
"S Uma",
""
],
[
"Shalgar",
"Shashank",
""
]
] |
We study the problem of determination of the sign of Delta m^2_{31}, or the neutrino mass hierarchy, through observations of atmospheric neutrinos in future detectors. We consider two proposed detector types : (a) Megaton sized water Cerenkov detectors, which can measure the survival rates of nu_\mu + \bar{\nu}_\mu and nu_e + \bar{\nu}_e and (b) 100 kton sized magnetized iron detectors, which can measure the survival rates of \nu_\mu and \bar{\nu}_\mu. For energies and path-lengths relevant to atmospheric neutrinos, these rates obtain significant matter contributions from P_{\mu e}, P_{\mu \mu} and P_{ee}, leading to an appreciable sensitivity to the hierarchy. We do a binned \chi^2 analysis of simulated data in these two types of detectors which includes the effect of smearing in neutrino energy and direction and incorporates detector efficiencies and relevant statistical, theoretical and systematic errors. We also marginalize the \chi^2 over the allowed ranges of neutrino parameters in order to accurately account for their uncertainties. Finally, we compare the performance of both types of detectors vis a vis the hierarchy determination.
|
1512.09318
|
Peter Petreczky
|
Swagato Mukherjee, P. Petreczky and S. Sharma
|
Charm hadrons above $T_c$
|
Talk presented at Quark Matter 2015, LaTeX, 4 pages, uses
nupha_ecrc.sty, ecrc.sty
| null |
10.1016/j.nuclphysa.2016.02.017
| null |
hep-ph hep-lat nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
From the analysis of the lattice data on fluctuations and correlations of
charm we conclude that open charm meson and baryon-like excitations exist above
the QCD crossover temperature, and in fact are the dominant degrees of freedom
for thermodynamics in the vicinity of the transition. Charm quarks become the
dominant charm degrees of freedom only for temperatures T>200 MeV.
|
[
{
"created": "Thu, 31 Dec 2015 16:22:51 GMT",
"version": "v1"
}
] |
2016-11-23
|
[
[
"Mukherjee",
"Swagato",
""
],
[
"Petreczky",
"P.",
""
],
[
"Sharma",
"S.",
""
]
] |
From the analysis of the lattice data on fluctuations and correlations of charm we conclude that open charm meson and baryon-like excitations exist above the QCD crossover temperature, and in fact are the dominant degrees of freedom for thermodynamics in the vicinity of the transition. Charm quarks become the dominant charm degrees of freedom only for temperatures T>200 MeV.
|
hep-ph/0105329
|
Adam Szczepaniak
|
Adam P. Szczepaniak and Maciej Swat
|
Role of Photoproduction in Exotic Meson Searches
|
10 pages, 2 figures inculded
|
Phys.Lett. B516 (2001) 72-76
|
10.1016/S0370-2693(01)00905-4
| null |
hep-ph
| null |
We discuss two production mechanisms of the $J^{PC}=1^{-+}$ exotic meson,
hadroproduction, using pion beams and photoproduction.
We show that the ratio of exotic to non-exotic, in particular the $a_2$,
meson production cross sections is expected to be by a factor of 5 to 10
larger, in photoproduction then in hadroproduction. Furthermore we show that
the low-t photoproduction of exotic meson is enhanced as compared to hadronic
production. This findings support the simple quark picture in which exotic
meson production is predicted to be enhanced when the beam is a virtual $Q\bar
Q$ pair with a spin-1 (photon) rather then with a spin-0 (pion).
|
[
{
"created": "Thu, 31 May 2001 02:07:31 GMT",
"version": "v1"
}
] |
2009-11-07
|
[
[
"Szczepaniak",
"Adam P.",
""
],
[
"Swat",
"Maciej",
""
]
] |
We discuss two production mechanisms of the $J^{PC}=1^{-+}$ exotic meson, hadroproduction, using pion beams and photoproduction. We show that the ratio of exotic to non-exotic, in particular the $a_2$, meson production cross sections is expected to be by a factor of 5 to 10 larger, in photoproduction then in hadroproduction. Furthermore we show that the low-t photoproduction of exotic meson is enhanced as compared to hadronic production. This findings support the simple quark picture in which exotic meson production is predicted to be enhanced when the beam is a virtual $Q\bar Q$ pair with a spin-1 (photon) rather then with a spin-0 (pion).
|
hep-ph/9308279
|
Marcelo Gleiser
|
Marcelo Gleiser
|
Pseudo-Stable Bubbles
|
10 pages, LaTeX (uses revtex 3.0), 4 figures (postscript files of
figs.1 and 2 appended starting on line 497), report DART-HEP-93/05
|
Phys.Rev. D49 (1994) 2978-2981
|
10.1103/PhysRevD.49.2978
| null |
hep-ph
| null |
The evolution of spherically symmetric unstable scalar field configurations
(``bubbles'') is examined for both symmetric (SDWP) and asymmetric (ADWP)
double-well potentials. Bubbles with initial static energies $E_0\la E_{{\rm
crit}}$, where $E_{{\rm crit}}$ is some critical value, shrink in a time scale
determined by their linear dimension, or ``radius''. Bubbles with $E_0\ga
E_{{\rm crit}}$ evolve into time-dependent, localized configurations which are
{\it very} long-lived compared to characteristic time-scales in the models
examined. The stability of these configurations is investigated and possible
applications are briefly discussed.tic time-scales in the models examined. The
stability of these configurations is investigated and possible applications are
briefly discussed.
|
[
{
"created": "Mon, 16 Aug 1993 17:36:36 GMT",
"version": "v1"
}
] |
2009-10-22
|
[
[
"Gleiser",
"Marcelo",
""
]
] |
The evolution of spherically symmetric unstable scalar field configurations (``bubbles'') is examined for both symmetric (SDWP) and asymmetric (ADWP) double-well potentials. Bubbles with initial static energies $E_0\la E_{{\rm crit}}$, where $E_{{\rm crit}}$ is some critical value, shrink in a time scale determined by their linear dimension, or ``radius''. Bubbles with $E_0\ga E_{{\rm crit}}$ evolve into time-dependent, localized configurations which are {\it very} long-lived compared to characteristic time-scales in the models examined. The stability of these configurations is investigated and possible applications are briefly discussed.tic time-scales in the models examined. The stability of these configurations is investigated and possible applications are briefly discussed.
|
2009.14209
|
Imre Majer
|
R. Gauld, A. Gehrmann-De Ridder, E. W. N. Glover, A. Huss, and I.
Majer
|
Precise predictions for $\mathrm{WH}$+jet production at the LHC
|
6 pages, 2 figures, 1 table
| null |
10.1016/j.physletb.2021.136335
|
NIKHEF 2020-034, ZU-TH 34/20, IPPP/20/45, CERN-TH-2020-163
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present precise predictions for the production of a Higgs boson in
association with a hadronic jet and a $\mathrm{W}$ boson at hadron colliders.
The behaviour of QCD corrections are studied for fiducial cross sections and
distributions of the charged gauge boson and jet-related observables. The
inclusive process (at least one resolved jet) and the exclusive process
(exactly one resolved jet) are contrasted and discussed. The inclusion of QCD
corrections up to $\mathcal{O}(\alpha_{\text{s}}^3)$ leads to a clear
stabilisation of the predictions and contributes substantially to a reduction
of remaining theoretical uncertainties.
|
[
{
"created": "Tue, 29 Sep 2020 18:00:02 GMT",
"version": "v1"
}
] |
2021-06-02
|
[
[
"Gauld",
"R.",
""
],
[
"Ridder",
"A. Gehrmann-De",
""
],
[
"Glover",
"E. W. N.",
""
],
[
"Huss",
"A.",
""
],
[
"Majer",
"I.",
""
]
] |
We present precise predictions for the production of a Higgs boson in association with a hadronic jet and a $\mathrm{W}$ boson at hadron colliders. The behaviour of QCD corrections are studied for fiducial cross sections and distributions of the charged gauge boson and jet-related observables. The inclusive process (at least one resolved jet) and the exclusive process (exactly one resolved jet) are contrasted and discussed. The inclusion of QCD corrections up to $\mathcal{O}(\alpha_{\text{s}}^3)$ leads to a clear stabilisation of the predictions and contributes substantially to a reduction of remaining theoretical uncertainties.
|
1510.00799
|
Kei Yagyu
|
Hiroshi Okada, Yuta Orikasa, Kei Yagyu
|
Higgs Triplet Model with Classically Conformal Invariance
|
References added
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss an extension of the minimal Higgs triplet model with a classically
conformal invariance and with a gauged $U(1)_{B-L}$ symmetry. In our scenario,
tiny masses of neutrinos are generated by a hybrid contribution from the type-I
and type-II seesaw mechanisms. The shape of the Higgs potential at low energies
is determined by solving one-loop renormalization group equations for all the
scalar quartic couplings with a set of initial values of parameters at the
Planck scale. We find a successful set of the parameters in which the
$U(1)_{B-L}$ symmetry is radiatively broken via the Coleman-Weinberg mechanism
at the ${\cal O}$(10) TeV scale, and the electroweak symmetry breaking is also
triggered by the $U(1)_{B-L}$ breaking. Under this configuration, we can
predict various low energy observables such as the mass spectrum of extra Higgs
bosons, and the mixing angles. Furthermore, using these predicted mass
parameters, we obtain upper limits on Yukawa couplings among an isospin triplet
Higgs field and lepton doublets from lepton flavor violation data.
|
[
{
"created": "Sat, 3 Oct 2015 09:21:01 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Oct 2015 17:20:40 GMT",
"version": "v2"
}
] |
2015-10-14
|
[
[
"Okada",
"Hiroshi",
""
],
[
"Orikasa",
"Yuta",
""
],
[
"Yagyu",
"Kei",
""
]
] |
We discuss an extension of the minimal Higgs triplet model with a classically conformal invariance and with a gauged $U(1)_{B-L}$ symmetry. In our scenario, tiny masses of neutrinos are generated by a hybrid contribution from the type-I and type-II seesaw mechanisms. The shape of the Higgs potential at low energies is determined by solving one-loop renormalization group equations for all the scalar quartic couplings with a set of initial values of parameters at the Planck scale. We find a successful set of the parameters in which the $U(1)_{B-L}$ symmetry is radiatively broken via the Coleman-Weinberg mechanism at the ${\cal O}$(10) TeV scale, and the electroweak symmetry breaking is also triggered by the $U(1)_{B-L}$ breaking. Under this configuration, we can predict various low energy observables such as the mass spectrum of extra Higgs bosons, and the mixing angles. Furthermore, using these predicted mass parameters, we obtain upper limits on Yukawa couplings among an isospin triplet Higgs field and lepton doublets from lepton flavor violation data.
|
hep-ph/0610214
|
Adeola Adeluyi
|
A. Adeluyi, G. Fai
|
Mass dependence of nuclear shadowing at small Bjorken-x from diffractive
scattering
|
To be published in Phys. Rev. C
|
Phys.Rev.C74:054904,2006
|
10.1103/PhysRevC.74.054904
|
KSUCNR-204-07
|
hep-ph
| null |
We calculate the nuclear shadowing ratio for a wide range of nuclei at small
Bjorken-x in the framework of Gribov theory. The coherent contribution to the
(virtual) photon-nucleon cross section is obtained in terms of the diffractive
dissociation cross section. Information on diffraction from FNAL and HERA is
used. Our results are compared to available experimental data from the NMC and
E665 experiments at x ~ 10^{-4}.
|
[
{
"created": "Tue, 17 Oct 2006 15:43:44 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Adeluyi",
"A.",
""
],
[
"Fai",
"G.",
""
]
] |
We calculate the nuclear shadowing ratio for a wide range of nuclei at small Bjorken-x in the framework of Gribov theory. The coherent contribution to the (virtual) photon-nucleon cross section is obtained in terms of the diffractive dissociation cross section. Information on diffraction from FNAL and HERA is used. Our results are compared to available experimental data from the NMC and E665 experiments at x ~ 10^{-4}.
|
hep-ph/0310240
|
Hans-Werner Hammer
|
H.-W. Hammer (Bonn U.), D. Drechsel (Mainz U.), and Ulf-G. Mei{\ss}ner
(Bonn U. and FZ J\"ulich)
|
On the pion cloud of the nucleon
|
7 pages, latex, 3 ps figures, minor changes
|
Phys.Lett. B586 (2004) 291-296
|
10.1016/j.physletb.2003.12.073
|
HISKP-TH-03/21
|
hep-ph nucl-th
| null |
We evaluate the two--pion contribution to the nucleon electromagnetic form
factors by use of dispersion analysis and chiral perturbation theory. After
subtraction of the rho--meson component, we calculate the distributions of
charge and magnetization in coordinate space, which can be interpreted as the
effects of the pion cloud. We find that the charge distribution of this pion
cloud effect peaks at distances of about 0.3 fm. Furthermore, we calculate the
contribution of the pion cloud to the isovector charges and radii of the
nucleon.
|
[
{
"created": "Mon, 20 Oct 2003 15:55:01 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Dec 2003 14:12:27 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Hammer",
"H. -W.",
"",
"Bonn U."
],
[
"Drechsel",
"D.",
"",
"Mainz U."
],
[
"Meißner",
"Ulf-G.",
"",
"Bonn U. and FZ Jülich"
]
] |
We evaluate the two--pion contribution to the nucleon electromagnetic form factors by use of dispersion analysis and chiral perturbation theory. After subtraction of the rho--meson component, we calculate the distributions of charge and magnetization in coordinate space, which can be interpreted as the effects of the pion cloud. We find that the charge distribution of this pion cloud effect peaks at distances of about 0.3 fm. Furthermore, we calculate the contribution of the pion cloud to the isovector charges and radii of the nucleon.
|
hep-ph/0410107
|
Federica Bazzocchi
|
F. Bazzocchi, M. Fabbrichesi
|
Flavor and electroweak symmetry breaking at the TeV scale
| null |
Nucl.Phys. B715 (2005) 372-412
|
10.1016/j.nuclphysb.2005.03.004
| null |
hep-ph
| null |
We present a unified picture of flavor and electroweak symmetry breaking at
the TeV scale. Flavor and Higgs bosons arise as pseudo-Goldstone modes in a
nonlinear sigma model. Explicit collective symmetry breaking yields stable
vacuum expectation values and masses protected at one loop by the little-Higgs
mechanism. The coupling to the fermions through a Yukawa lagrangian with a U(1)
global flavor symmetry generates well-definite mass textures that correctly
reproduce the mass hierarchies and mixings of quarks and leptons. The model is
more constrained than usual little- Higgs models because of bounds on weak and
flavor physics. The main experimental signatures testable at the LHC are a
rather large mass mh0 = 317+/-80 GeV for the (lightest) Higgs boson and a
characteristic spectrum of new bosons and fermions with masses around the TeV
scale.
|
[
{
"created": "Thu, 7 Oct 2004 14:01:24 GMT",
"version": "v1"
}
] |
2009-11-10
|
[
[
"Bazzocchi",
"F.",
""
],
[
"Fabbrichesi",
"M.",
""
]
] |
We present a unified picture of flavor and electroweak symmetry breaking at the TeV scale. Flavor and Higgs bosons arise as pseudo-Goldstone modes in a nonlinear sigma model. Explicit collective symmetry breaking yields stable vacuum expectation values and masses protected at one loop by the little-Higgs mechanism. The coupling to the fermions through a Yukawa lagrangian with a U(1) global flavor symmetry generates well-definite mass textures that correctly reproduce the mass hierarchies and mixings of quarks and leptons. The model is more constrained than usual little- Higgs models because of bounds on weak and flavor physics. The main experimental signatures testable at the LHC are a rather large mass mh0 = 317+/-80 GeV for the (lightest) Higgs boson and a characteristic spectrum of new bosons and fermions with masses around the TeV scale.
|
2111.04088
|
Volodymyr Takhistov
|
Volodymyr Takhistov
|
Neutrino and Axion Astronomy with Dark Matter Experiments
|
5 pages, 3 figures, Proceedings of the 17th International Conference
on Topics in Astroparticle and Underground Physics (TAUP 2021), 30 August - 3
September 2021, Valencia, Spain - Online
| null |
10.1088/1742-6596/2156/1/012049
|
IPMU21-0077
|
hep-ph astro-ph.CO astro-ph.HE hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Sensitive dark matter (DM) experiments can be well exploited beyond their
designated targets, allowing to explore a breadth of physics topics. As we
discuss, future large direct DM detection experiments constitute impressive
telescopes, complementary to conventional neutrino detectors. This opens a new
window into neutrino astronomy, including puzzles such as the origin of
supermassive black holes and topics like supernova forecast. Furthermore, DM
experiments can act as effective instruments for multimessenger astronomy. This
is well illustrated by exploration of relativistic axions from transient
astrophysical sources (e.g. axion star explosions), providing novel signatures
as well as possible insights into the axion potential.
|
[
{
"created": "Sun, 7 Nov 2021 13:41:52 GMT",
"version": "v1"
}
] |
2022-03-02
|
[
[
"Takhistov",
"Volodymyr",
""
]
] |
Sensitive dark matter (DM) experiments can be well exploited beyond their designated targets, allowing to explore a breadth of physics topics. As we discuss, future large direct DM detection experiments constitute impressive telescopes, complementary to conventional neutrino detectors. This opens a new window into neutrino astronomy, including puzzles such as the origin of supermassive black holes and topics like supernova forecast. Furthermore, DM experiments can act as effective instruments for multimessenger astronomy. This is well illustrated by exploration of relativistic axions from transient astrophysical sources (e.g. axion star explosions), providing novel signatures as well as possible insights into the axion potential.
|
1307.6460
|
Sonny Mantry
|
Zhong-Bo Kang, Xiaohui Liu, Sonny Mantry, Jian-Wei Qiu
|
The 1-Jettiness event shape for DIS with NNLL resummation
|
To appear in the proceedings of the QCD Evolution Workshop, JLab, May
6th-10th, 2013
|
Int. J. Mod. Phys. Conf. Ser. 25, 1460041 (2014)
|
10.1142/S2010194514600416
| null |
hep-ph nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We propose the use of 1-jettiness, a global event shape, for exclusive single
jet production in lepton-nucleus deep inelastic scattering (DIS). We derive a
factorization formula, using the Soft-Collinear Effective Theory, differential
in the transverse momentum and rapidity of the jet and the 1-jettiness event
shape. It provides a quantitative measure of the shape of the final-state QCD
radiation in the presence of the hard jet, providing a useful powerful probe of
QCD and nuclear physics. For example, one expects differences in the observed
pattern of QCD radiation between large and small nuclei and these can be
quantified by the 1-jettiness event shape. Numerical results are given for this
new DIS event shape at leading twist with resummation at the
next-to-next-to-leading logarithmic (NNLL) level of accuracy, for a variety of
nuclear targets. Such studies would be ideal at a future EIC or LHeC
electron-ion collider, where a range of nuclear targets are planned.
|
[
{
"created": "Wed, 24 Jul 2013 15:38:45 GMT",
"version": "v1"
}
] |
2014-01-13
|
[
[
"Kang",
"Zhong-Bo",
""
],
[
"Liu",
"Xiaohui",
""
],
[
"Mantry",
"Sonny",
""
],
[
"Qiu",
"Jian-Wei",
""
]
] |
We propose the use of 1-jettiness, a global event shape, for exclusive single jet production in lepton-nucleus deep inelastic scattering (DIS). We derive a factorization formula, using the Soft-Collinear Effective Theory, differential in the transverse momentum and rapidity of the jet and the 1-jettiness event shape. It provides a quantitative measure of the shape of the final-state QCD radiation in the presence of the hard jet, providing a useful powerful probe of QCD and nuclear physics. For example, one expects differences in the observed pattern of QCD radiation between large and small nuclei and these can be quantified by the 1-jettiness event shape. Numerical results are given for this new DIS event shape at leading twist with resummation at the next-to-next-to-leading logarithmic (NNLL) level of accuracy, for a variety of nuclear targets. Such studies would be ideal at a future EIC or LHeC electron-ion collider, where a range of nuclear targets are planned.
|
1612.05194
|
Kei Yagyu
|
A. G. Akeroyd, Stefano Moretti, Kei Yagyu, Emine Yildirim
|
Light charged Higgs boson scenario in 3HDMs
|
Prepared for proceedings for Charged2016, talk presented by Kei Yagyu
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The measurement of the $B\to X_s\gamma$ process gives important constraints
on physics related to charged Higgs bosons ($H^\pm$). In 2-Higgs Doublet Models
(2HDMs) with a softly-broken $Z_2$ symmetry, a light $H^\pm$ scenario, in which
$H^\pm$ can be produced via the top decay, is possible in two of four types of
Yukawa interactions (the so-called Type-I and Type-X). In these types of 2HDMs,
the $H^\pm \to \tau^\pm \nu$ decay mode is dominant in wide regions of the
parameter space. In this report, we discuss the other possibility of a light
charged Higgs boson scenario in 3-Higgs-Doublet Models (3HDMs) based on the
results obtained in Ref. [1]. We show that charged Higgs bosons can mainly
decay into $cb$ without contradiction with the $B\to X_s\gamma$ data and the
direct searches for charged Higgs bosons at the LHC, and this scenario cannot
be realized in the 2HDMs.
|
[
{
"created": "Thu, 15 Dec 2016 19:12:23 GMT",
"version": "v1"
}
] |
2016-12-16
|
[
[
"Akeroyd",
"A. G.",
""
],
[
"Moretti",
"Stefano",
""
],
[
"Yagyu",
"Kei",
""
],
[
"Yildirim",
"Emine",
""
]
] |
The measurement of the $B\to X_s\gamma$ process gives important constraints on physics related to charged Higgs bosons ($H^\pm$). In 2-Higgs Doublet Models (2HDMs) with a softly-broken $Z_2$ symmetry, a light $H^\pm$ scenario, in which $H^\pm$ can be produced via the top decay, is possible in two of four types of Yukawa interactions (the so-called Type-I and Type-X). In these types of 2HDMs, the $H^\pm \to \tau^\pm \nu$ decay mode is dominant in wide regions of the parameter space. In this report, we discuss the other possibility of a light charged Higgs boson scenario in 3-Higgs-Doublet Models (3HDMs) based on the results obtained in Ref. [1]. We show that charged Higgs bosons can mainly decay into $cb$ without contradiction with the $B\to X_s\gamma$ data and the direct searches for charged Higgs bosons at the LHC, and this scenario cannot be realized in the 2HDMs.
|
hep-ph/0404010
|
Franco Giuliani
|
F. Giuliani
|
Model-independent assessment of current direct searches for
spin-dependent dark matter
|
4 pages, 4 figures, revised and accepted for publication on Phys.
Rev. Lett
|
Phys.Rev.Lett.93:161301,2004
|
10.1103/PhysRevLett.93.161301
| null |
hep-ph astro-ph
| null |
I evaluate the current results of spin-dependent weakly interacting massive
particle (WIMP) searches within a model-independent framework, showing the most
restrictive limits to date derive from the combination of xenon and sodium
iodide experiments. The extension of this analysis to the case of positive
signal experiments is elaborated.
|
[
{
"created": "Thu, 1 Apr 2004 17:20:16 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Sep 2004 14:24:39 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Giuliani",
"F.",
""
]
] |
I evaluate the current results of spin-dependent weakly interacting massive particle (WIMP) searches within a model-independent framework, showing the most restrictive limits to date derive from the combination of xenon and sodium iodide experiments. The extension of this analysis to the case of positive signal experiments is elaborated.
|
hep-ph/0002082
|
Costas Papadopoulos
|
Aggeliki Kanaki and Costas G. Papadopoulos
|
HELAC: a package to compute electroweak helicity amplitudes
|
14 pages
|
Comput.Phys.Commun. 132 (2000) 306-315
|
10.1016/S0010-4655(00)00151-X
|
DEMO-HEP-2000/01
|
hep-ph
| null |
HELAC is a FORTRAN based package that is able to compute efficiently helicity
amplitudes for arbitrary scattering processes within the standard electroweak
theory. The algorithm exploits the virtues of the Dyson-Schwinger equations as
compared to the traditional Feynman graph approach. All electroweak vertices
are included in both the unitary and Feynman gauges, and computations including
all mass effects are available. A version performing multi-precision
computations with arbitrary - user defined - accuracy is also included,
allowing access to any phase space point for arbitrary high energies.
|
[
{
"created": "Tue, 8 Feb 2000 09:27:06 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Feb 2000 07:54:24 GMT",
"version": "v2"
}
] |
2009-10-31
|
[
[
"Kanaki",
"Aggeliki",
""
],
[
"Papadopoulos",
"Costas G.",
""
]
] |
HELAC is a FORTRAN based package that is able to compute efficiently helicity amplitudes for arbitrary scattering processes within the standard electroweak theory. The algorithm exploits the virtues of the Dyson-Schwinger equations as compared to the traditional Feynman graph approach. All electroweak vertices are included in both the unitary and Feynman gauges, and computations including all mass effects are available. A version performing multi-precision computations with arbitrary - user defined - accuracy is also included, allowing access to any phase space point for arbitrary high energies.
|
hep-ph/0206166
|
Ed Stoeffhaas
|
M.M. Block and G. Pancheri
|
Forward Elastic Scattering of Light on Light,
\gamma+\gamma\to\gamma+\gamma
|
5 pages, Latex2e, 2 postscript figures, uses epsfig.sty
|
Eur.Phys.J.C25:287-289,2002
|
10.1007/s10052-002-1019-6
|
NUHEP 1001
|
hep-ph
| null |
The forward elastic scattering of light on light, {\em i.e.,} the reaction
$\gamma+\gamma \to \gamma+\gamma$ in the forward direction, is analyzed
utilizing real analytic amplitudes. We calculate $\rho_{\gamma \gamma}$, the
ratio of the real to the imaginary portion of the forward scattering amplitude,
by fitting the total $\gamma \gamma$ cross section data in the high energy
region $5 GeV \le \sqrt s \le 130 $ GeV, assuming a cross section that rises
asymptotically as $\ln^2 s$. We then compare $\rho_{\gamma\gamma}$ to
$\rho_{nn}$, the ratio of the even portions of the $pp$ and $\pbar p$ forward
scattering amplitudes, as well as to $\rho_{\gamma p}$, the $\rho$ value for
Compton scattering. Within errors, we find that the three $\rho$-values in the
c.m.s. energy region $5 GeV \le \sqrt s \le 130$ GeV are the same, as predicted
by a factorization theorem of Block and Kadailov.
|
[
{
"created": "Tue, 18 Jun 2002 20:17:37 GMT",
"version": "v1"
}
] |
2009-01-07
|
[
[
"Block",
"M. M.",
""
],
[
"Pancheri",
"G.",
""
]
] |
The forward elastic scattering of light on light, {\em i.e.,} the reaction $\gamma+\gamma \to \gamma+\gamma$ in the forward direction, is analyzed utilizing real analytic amplitudes. We calculate $\rho_{\gamma \gamma}$, the ratio of the real to the imaginary portion of the forward scattering amplitude, by fitting the total $\gamma \gamma$ cross section data in the high energy region $5 GeV \le \sqrt s \le 130 $ GeV, assuming a cross section that rises asymptotically as $\ln^2 s$. We then compare $\rho_{\gamma\gamma}$ to $\rho_{nn}$, the ratio of the even portions of the $pp$ and $\pbar p$ forward scattering amplitudes, as well as to $\rho_{\gamma p}$, the $\rho$ value for Compton scattering. Within errors, we find that the three $\rho$-values in the c.m.s. energy region $5 GeV \le \sqrt s \le 130$ GeV are the same, as predicted by a factorization theorem of Block and Kadailov.
|
hep-ph/0309290
|
Yili Wang
|
Yili Wang
|
Chargino Contributions in $B \to \phi K_S$ Asymmetry
| null |
Phys.Rev. D69 (2004) 054001
|
10.1103/PhysRevD.69.054001
| null |
hep-ph
| null |
CP asymmetry in $B \to \phi K_S$ decay is studied in a special context of
supersymmetry theories, in which the charginos play an important role. We find
that in addition to the gluino, chargino can also make large contributions to
CP asymmetry in $B \to \phi K_S$ decay. After considering the constraints from
$B \to J/psi K_S$ decay, we study three special scenarios: (a). Large mixing on
left-handed charm and top squarks (LL mixing); (b). Large mixing on
right-handed charm and top squarks (RR mixing); (c). Large mixing on
left-handed charm and top squarks plus right-handed charm and top squarks (LL +
RR mixing). We show quantitatively that because of large squark mixing within
second and third generations, an $\mathcal O$(1) effect on CP violation in $B
\to \phi K_S$ is possible.
|
[
{
"created": "Thu, 25 Sep 2003 15:52:32 GMT",
"version": "v1"
},
{
"created": "Sat, 1 Nov 2003 23:23:56 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Wang",
"Yili",
""
]
] |
CP asymmetry in $B \to \phi K_S$ decay is studied in a special context of supersymmetry theories, in which the charginos play an important role. We find that in addition to the gluino, chargino can also make large contributions to CP asymmetry in $B \to \phi K_S$ decay. After considering the constraints from $B \to J/psi K_S$ decay, we study three special scenarios: (a). Large mixing on left-handed charm and top squarks (LL mixing); (b). Large mixing on right-handed charm and top squarks (RR mixing); (c). Large mixing on left-handed charm and top squarks plus right-handed charm and top squarks (LL + RR mixing). We show quantitatively that because of large squark mixing within second and third generations, an $\mathcal O$(1) effect on CP violation in $B \to \phi K_S$ is possible.
|
1708.08233
|
Jiri Hosek
|
Jiri Hosek and J.Adam, Jr
|
On the Origin of Lepton and Quark Masses
|
6 pages
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Gauging the flavor (family, generation, horizontal) index of the chiral
fermion fields of the Standard model, for anomaly freedom extended by three
sterile right-handed neutrino fields, results in asymptotically free, {\it bona
fide} nonconfining $SU(3)_f$ quantum flavor dynamics. Approximate
nonperturbative strong-coupling solutions of the corresponding Schwinger-Dyson
(SD) equation for fermion self-energies give rise to the complete flavor
symmetry breaking by : (1) Three huge Majorana masses of sterile right-handed
neutrinos. (2) Three exponentially light Dirac masses common to all fermion
sorts in a family. Masses of charged leptons and quarks are further
distinguished from Dirac neutrino masses by the weak hypercharge contributions
to the universal $SU(3)_f$ kernel of the SD equation, free of unknown
parameters. The $SU(3)_f$ dynamics itself thus gives the neutrino mass spectrum
in the seesaw form.
|
[
{
"created": "Mon, 28 Aug 2017 08:26:48 GMT",
"version": "v1"
}
] |
2017-08-29
|
[
[
"Hosek",
"Jiri",
""
],
[
"Adam,",
"J.",
"Jr"
]
] |
Gauging the flavor (family, generation, horizontal) index of the chiral fermion fields of the Standard model, for anomaly freedom extended by three sterile right-handed neutrino fields, results in asymptotically free, {\it bona fide} nonconfining $SU(3)_f$ quantum flavor dynamics. Approximate nonperturbative strong-coupling solutions of the corresponding Schwinger-Dyson (SD) equation for fermion self-energies give rise to the complete flavor symmetry breaking by : (1) Three huge Majorana masses of sterile right-handed neutrinos. (2) Three exponentially light Dirac masses common to all fermion sorts in a family. Masses of charged leptons and quarks are further distinguished from Dirac neutrino masses by the weak hypercharge contributions to the universal $SU(3)_f$ kernel of the SD equation, free of unknown parameters. The $SU(3)_f$ dynamics itself thus gives the neutrino mass spectrum in the seesaw form.
|
2310.03463
|
Harleen Dahiya Dr.
|
Shubham Sharma and Harleen Dahiya
|
Exploring twist-4 chiral-even GPDs in the light-front quark-diquark
model
|
27 pages, 6 figures and 2 tables
|
Nucl. Phys. B, 1002, 116522 (2024)
|
10.1016/j.nuclphysb.2024.116522
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this work, we delve into the realm of quantum chromodynamics (QCD) by
calculating twist-4 chiral-even generalized parton distributions (GPDs), within
the context of the light-front quark-diquark model (LFQDM), focusing
specifically on the intriguing case of zero skewness. To shed light on the
behavior of twist-4 chiral-even GPDs, we present comprehensive two-dimensional
($2$-D) and 3-dimensional ($3$-D) plots, mapping their dependence on the
longitudinal momentum fraction ($x$) and the momentum transfer ($t$).
Furthermore, our research looks into the profound connection between twist-4
chiral-even GPDs and other distribution functions (DFs), including parton
distribution functions (PDFs), transverse momentum-dependent parton
distributions (TMDs) and generalized transverse-momentum dependent parton
distributions (GTMDs). Additionally, our investigation extends to the
exploration of related higher twist form factors (FFs), which play a pivotal
role in elucidating the internal structure of hadrons. To provide significant
insights into the partons spatial distribution, we have also yielded impact
parameter GPD plots.
|
[
{
"created": "Thu, 5 Oct 2023 11:20:44 GMT",
"version": "v1"
}
] |
2024-05-02
|
[
[
"Sharma",
"Shubham",
""
],
[
"Dahiya",
"Harleen",
""
]
] |
In this work, we delve into the realm of quantum chromodynamics (QCD) by calculating twist-4 chiral-even generalized parton distributions (GPDs), within the context of the light-front quark-diquark model (LFQDM), focusing specifically on the intriguing case of zero skewness. To shed light on the behavior of twist-4 chiral-even GPDs, we present comprehensive two-dimensional ($2$-D) and 3-dimensional ($3$-D) plots, mapping their dependence on the longitudinal momentum fraction ($x$) and the momentum transfer ($t$). Furthermore, our research looks into the profound connection between twist-4 chiral-even GPDs and other distribution functions (DFs), including parton distribution functions (PDFs), transverse momentum-dependent parton distributions (TMDs) and generalized transverse-momentum dependent parton distributions (GTMDs). Additionally, our investigation extends to the exploration of related higher twist form factors (FFs), which play a pivotal role in elucidating the internal structure of hadrons. To provide significant insights into the partons spatial distribution, we have also yielded impact parameter GPD plots.
|
hep-ph/9910427
|
Marc Vanderhaeghen
|
Barry R. Holstein, D. Drechsel, B. Pasquini, M. Vanderhaeghen
|
Higher Order Polarizabilities of the Proton
|
18 pages, revised version with one reference added
|
Phys.Rev. C61 (2000) 034316
|
10.1103/PhysRevC.61.034316
| null |
hep-ph
| null |
Compton scattering results are used to probe proton structure via measurement
of higher order polarizabilities. Values for
$\alpha_{E2}^p,\beta_{E2}^p,\alpha_{E\nu}^p,$ $\beta_{E\nu}^p$ determined via
dispersion relations are compared to predictions based upon chiral symmetry and
from the constituent quark model. Extensions to spin-polarizabilities are also
discussed.
|
[
{
"created": "Thu, 21 Oct 1999 09:47:28 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Oct 1999 17:51:37 GMT",
"version": "v2"
}
] |
2016-09-06
|
[
[
"Holstein",
"Barry R.",
""
],
[
"Drechsel",
"D.",
""
],
[
"Pasquini",
"B.",
""
],
[
"Vanderhaeghen",
"M.",
""
]
] |
Compton scattering results are used to probe proton structure via measurement of higher order polarizabilities. Values for $\alpha_{E2}^p,\beta_{E2}^p,\alpha_{E\nu}^p,$ $\beta_{E\nu}^p$ determined via dispersion relations are compared to predictions based upon chiral symmetry and from the constituent quark model. Extensions to spin-polarizabilities are also discussed.
|
hep-ph/9907435
|
Evgeny Akhmedov
|
E. Kh. Akhmedov (IST, Lisbon and Kurchatov Inst., Moscow)
|
Parametric resonance in neutrino oscillations in matter
|
LaTeX, 20 pages, 8 figures, requires epsfig. Invited review article
to be published in the special issue of Pramana dedicated to neutrino physics
|
Pramana 54:47-63,2000
| null |
FISIST/12-99/CFIF
|
hep-ph astro-ph hep-ex
| null |
Neutrino oscillations in matter can exhibit a specific resonance enhancement
-- parametric resonance, which is different from the MSW resonance.
Oscillations of atmospheric and solar neutrinos inside the earth can undergo
parametric enhancement when neutrino trajectories cross the core of the earth.
In this paper we review the parametric resonance of neutrino oscillations in
matter. In particular, physical interpretation of the effect and the prospects
of its experimental observation in oscillations of solar and atmospheric
neutrinos in the earth are discussed.
|
[
{
"created": "Tue, 20 Jul 1999 17:48:08 GMT",
"version": "v1"
}
] |
2009-06-19
|
[
[
"Akhmedov",
"E. Kh.",
"",
"IST, Lisbon and Kurchatov Inst., Moscow"
]
] |
Neutrino oscillations in matter can exhibit a specific resonance enhancement -- parametric resonance, which is different from the MSW resonance. Oscillations of atmospheric and solar neutrinos inside the earth can undergo parametric enhancement when neutrino trajectories cross the core of the earth. In this paper we review the parametric resonance of neutrino oscillations in matter. In particular, physical interpretation of the effect and the prospects of its experimental observation in oscillations of solar and atmospheric neutrinos in the earth are discussed.
|
1307.7700
|
Antonio Pich
|
Antonio Pich
|
The Physics of the Higgs-like Boson
|
Invited talk at the LHCP 2013 Conference (Barcelona, Spain, 13-18 May
2013). 6 pages, 8 figures
| null |
10.1051/epjconf/20136002006
|
IFIC/13-51, FTUV/13-0729
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The present knowledge on the Higgs-like boson discovered at the LHC is
summarized. The data accumulated so far are consistent with the Standard Model
predictions and put interesting constraints on alternative scenarios of
electroweak symmetry breaking. The measured couplings to gauge bosons and
third-generation fermions indicate that a Higgs particle has indeed been found.
More precise data are needed to clarify whether it is the unique Higgs boson of
the Standard Model or the first member of a new variety of dynamical (either
elementary or composite) fields.
|
[
{
"created": "Mon, 29 Jul 2013 19:45:01 GMT",
"version": "v1"
}
] |
2015-06-16
|
[
[
"Pich",
"Antonio",
""
]
] |
The present knowledge on the Higgs-like boson discovered at the LHC is summarized. The data accumulated so far are consistent with the Standard Model predictions and put interesting constraints on alternative scenarios of electroweak symmetry breaking. The measured couplings to gauge bosons and third-generation fermions indicate that a Higgs particle has indeed been found. More precise data are needed to clarify whether it is the unique Higgs boson of the Standard Model or the first member of a new variety of dynamical (either elementary or composite) fields.
|
hep-ph/0512033
|
Erik Lundstrom
|
E. Lundstrom
|
Detection of elastic photon-photon scattering through four-wave coupling
|
MSc thesis. 70 pages, 8 figures. Including appendix with the
geometric factors referred to in hep-ph/0510076
| null | null | null |
hep-ph
| null |
According to the theory of quantum electrodynamics, photon-photon scattering
can take place via exchange of virtual electron-positron pairs. Effectively,
the interaction can be formulated in terms of non-linear corrections to
Maxwell's equations, and hence may be treated by classical non-linear
electrodynamics. Due to the strong electromagnetic fields needed to reach any
noticeable effect, photon-photon scattering has not yet been observed
experimentally, but recent improvements in laser technology have increased the
possibility of direct detection. A verification of the phenomena would be of
great scientific value as a confirmation of quantum electrodynamics. In this
thesis the possibility of direct detection of elastic photon-photon scattering
through four-wave coupling is investigated, both for current and future
systems. It is shown how three colliding laser pulses satisfying certain
matching conditions, can generate scattered radiation in a fourth resonant
direction. The interaction is modeled, and the number of scattered photons is
estimated for optimized configurations of incoming pulses, both for the Vulcan
laser at the Rutherford Appleton Laboratory as well as for the planned XFEL at
DESY. An experiment using the Vulcan laser is predicted to produce 22 scattered
photons per shot, an amount which is definitely detectable. The usefulness of
the XFEL highly depends on future developments in laser technology, but a
realistic estimation gives a result of 30000 scattered photons per second.
|
[
{
"created": "Fri, 2 Dec 2005 13:32:42 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Lundstrom",
"E.",
""
]
] |
According to the theory of quantum electrodynamics, photon-photon scattering can take place via exchange of virtual electron-positron pairs. Effectively, the interaction can be formulated in terms of non-linear corrections to Maxwell's equations, and hence may be treated by classical non-linear electrodynamics. Due to the strong electromagnetic fields needed to reach any noticeable effect, photon-photon scattering has not yet been observed experimentally, but recent improvements in laser technology have increased the possibility of direct detection. A verification of the phenomena would be of great scientific value as a confirmation of quantum electrodynamics. In this thesis the possibility of direct detection of elastic photon-photon scattering through four-wave coupling is investigated, both for current and future systems. It is shown how three colliding laser pulses satisfying certain matching conditions, can generate scattered radiation in a fourth resonant direction. The interaction is modeled, and the number of scattered photons is estimated for optimized configurations of incoming pulses, both for the Vulcan laser at the Rutherford Appleton Laboratory as well as for the planned XFEL at DESY. An experiment using the Vulcan laser is predicted to produce 22 scattered photons per shot, an amount which is definitely detectable. The usefulness of the XFEL highly depends on future developments in laser technology, but a realistic estimation gives a result of 30000 scattered photons per second.
|
hep-ph/9308353
|
Oscar Eboli
|
F.T. Brandt, O.J.P. Eboli, E.M. Gregores, M.B. Magro, P.G. Mercadante,
and S.F. Novaes
|
Triple Vector Boson Processes in $\gamma\gamma$ Colliders
|
uses REVTeX 3, 13 pages and 7 figures (available upon request or ftp
anonymous), IFUSP-P 1065 and IFT-P.053/93. (References added and minor
changes)
|
Phys.Rev. D50 (1994) 5591-5601
|
10.1103/PhysRevD.50.5591
| null |
hep-ph
| null |
We study the production of three gauge bosons at the next generation of
linear $e^+e^-$ colliders operating in the $\gamma\gamma$ mode. The processes
$\gamma\gamma \rightarrow W^+W^-V$ ($V=Z^0$, or $\gamma$) can provide direct
information about the quartic gauge-boson couplings. We analyze the total cross
section as well as several dynamical distributions of the final state particles
including the effect of kinematical cuts. We find out that a linear $e^+e^-$
machine operating in the $\gamma\gamma$ mode will produce 5--10 times more
three-gauge-boson states compared to the standard $e^+e^-$ mode at high
energies.
|
[
{
"created": "Fri, 27 Aug 1993 19:09:36 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Sep 1993 14:14:53 GMT",
"version": "v2"
}
] |
2009-10-22
|
[
[
"Brandt",
"F. T.",
""
],
[
"Eboli",
"O. J. P.",
""
],
[
"Gregores",
"E. M.",
""
],
[
"Magro",
"M. B.",
""
],
[
"Mercadante",
"P. G.",
""
],
[
"Novaes",
"S. F.",
""
]
] |
We study the production of three gauge bosons at the next generation of linear $e^+e^-$ colliders operating in the $\gamma\gamma$ mode. The processes $\gamma\gamma \rightarrow W^+W^-V$ ($V=Z^0$, or $\gamma$) can provide direct information about the quartic gauge-boson couplings. We analyze the total cross section as well as several dynamical distributions of the final state particles including the effect of kinematical cuts. We find out that a linear $e^+e^-$ machine operating in the $\gamma\gamma$ mode will produce 5--10 times more three-gauge-boson states compared to the standard $e^+e^-$ mode at high energies.
|
1504.04022
|
Joachim Brod
|
Fady Bishara, Joachim Brod, Patipan Uttayarat, Jure Zupan
|
Nonstandard Yukawa Couplings and Higgs Portal Dark Matter
|
38 pages, 12 figures; minor mistake in numerics fixed, conclusions
unchanged; references added
| null |
10.1007/JHEP01(2016)010
|
FERMILAB-PUB-15-134-T, MITP/15-020
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the implications of non-standard Higgs Yukawa couplings to light
quarks on Higgs-portal dark matter phenomenology. Saturating the present
experimental bounds on up-quark, down-quark, or strange-quark Yukawa couplings,
the predicted direct dark matter detection scattering rate can increase by up
to four orders of magnitude. The effect on the dark matter annihilation cross
section, on the other hand, is subleading unless the dark matter is very light
-- a scenario that is already excluded by measurements of the Higgs invisible
decay width. We investigate the expected size of corrections in
multi-Higgs-doublet models with natural flavor conservation, the type-II
two-Higgs-doublet model, the Giudice-Lebedev model of light quark masses,
minimal flavor violation new physics models, Randall-Sundrum, and composite
Higgs models. We find that an enhancement in the dark matter scattering rate of
an order of magnitude is possible. Finally, we point out that a discovery of
Higgs-portal dark matter could lead to interesting bounds on the light-quark
Yukawa couplings.
|
[
{
"created": "Wed, 15 Apr 2015 20:01:06 GMT",
"version": "v1"
},
{
"created": "Fri, 15 May 2015 11:25:41 GMT",
"version": "v2"
}
] |
2016-01-27
|
[
[
"Bishara",
"Fady",
""
],
[
"Brod",
"Joachim",
""
],
[
"Uttayarat",
"Patipan",
""
],
[
"Zupan",
"Jure",
""
]
] |
We study the implications of non-standard Higgs Yukawa couplings to light quarks on Higgs-portal dark matter phenomenology. Saturating the present experimental bounds on up-quark, down-quark, or strange-quark Yukawa couplings, the predicted direct dark matter detection scattering rate can increase by up to four orders of magnitude. The effect on the dark matter annihilation cross section, on the other hand, is subleading unless the dark matter is very light -- a scenario that is already excluded by measurements of the Higgs invisible decay width. We investigate the expected size of corrections in multi-Higgs-doublet models with natural flavor conservation, the type-II two-Higgs-doublet model, the Giudice-Lebedev model of light quark masses, minimal flavor violation new physics models, Randall-Sundrum, and composite Higgs models. We find that an enhancement in the dark matter scattering rate of an order of magnitude is possible. Finally, we point out that a discovery of Higgs-portal dark matter could lead to interesting bounds on the light-quark Yukawa couplings.
|
hep-ph/0012223
|
Stephen C. Davis
|
Stephen C. Davis, Warren B. Perkins, Anne-Christine Davis and Ian R.
Vernon
|
Cosmological Phase Transitions in a Brane World
|
RevTeX, 9 pages. This paper was previously part of hep-ph/0008132.
v2: section 5 corrected
|
Phys.Rev.D63:083518,2001
|
10.1103/PhysRevD.63.083518
|
DAMTP-2000-138, SWAT/264B
|
hep-ph astro-ph gr-qc hep-th
| null |
In brane world scenarios the Friedmann equation is modified, resulting in an
increased expansion at early times. This has important effects on cosmological
phase transitions which we investigate, elucidating significant differences to
the standard case. First order phase transitions require a higher nucleation
rate to complete; baryogenesis and particle abundances could be suppressed.
Topological defect evolution is also affected, though the current defect
densities are largely unchanged. In particular, the increased expansion does
not solve the usual monopole and domain wall problems.
|
[
{
"created": "Mon, 18 Dec 2000 13:04:51 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Aug 2001 14:37:08 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Davis",
"Stephen C.",
""
],
[
"Perkins",
"Warren B.",
""
],
[
"Davis",
"Anne-Christine",
""
],
[
"Vernon",
"Ian R.",
""
]
] |
In brane world scenarios the Friedmann equation is modified, resulting in an increased expansion at early times. This has important effects on cosmological phase transitions which we investigate, elucidating significant differences to the standard case. First order phase transitions require a higher nucleation rate to complete; baryogenesis and particle abundances could be suppressed. Topological defect evolution is also affected, though the current defect densities are largely unchanged. In particular, the increased expansion does not solve the usual monopole and domain wall problems.
|
1202.2364
|
Kfir Blum
|
Kfir Blum and Raffaele Tito D'Agnolo
|
2 Higgs or not 2 Higgs
|
5 pages, 1 figure. v2: corrected error at order $(mh/mH)^4$ in
eqs.(8-9), added comment about spurion analysis in footnote 1, updated figure
1. No qualitative and no significant numerical change
| null |
10.1016/j.physletb.2012.06.054
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Motivated by recent results from the LHC experiments, we analyze Higgs
couplings in two Higgs doublet models with an approximate PQ symmetry. Models
of this kind can naturally accommodate sizable modifications to Higgs decay
patterns while leaving production at hadron colliders untouched. Near the
decoupling limit, we integrate out the heavy doublet to obtain the effective
couplings of the SM-like Higgs and express these couplings in a physically
transparent way, keeping all orders in (m_h/m_H) for small PQ breaking.
Considering supersymmetric models, we show that the effects on the Higgs
couplings are considerably constrained.
|
[
{
"created": "Fri, 10 Feb 2012 21:00:10 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Apr 2014 14:11:25 GMT",
"version": "v2"
}
] |
2015-06-04
|
[
[
"Blum",
"Kfir",
""
],
[
"D'Agnolo",
"Raffaele Tito",
""
]
] |
Motivated by recent results from the LHC experiments, we analyze Higgs couplings in two Higgs doublet models with an approximate PQ symmetry. Models of this kind can naturally accommodate sizable modifications to Higgs decay patterns while leaving production at hadron colliders untouched. Near the decoupling limit, we integrate out the heavy doublet to obtain the effective couplings of the SM-like Higgs and express these couplings in a physically transparent way, keeping all orders in (m_h/m_H) for small PQ breaking. Considering supersymmetric models, we show that the effects on the Higgs couplings are considerably constrained.
|
1603.02013
|
Tianhong Wang
|
Qiang Li, Tianhong Wang, Yue Jiang, Han Yuan, Guo-Li Wang
|
$D$-Wave Charmonia $\eta_{c2}$($1{^1D_2}$), $\psi_2$($1{^3D_2}$), and
$\psi_3$($1{^3D_3}$) in $B_c$ Decays
|
18 pages, 9 figures
|
Eur. Phys. J. C (2016) 76: 454
|
10.1140/epjc/s10052-016-4306-3
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the semi-leptonic and non-leptonic decays of $B_c$ meson to $D$-wave
charmonia, namely, $\eta_{c2}(1^1\!D_2)$, $\psi_2(1^3\!D_2)$, and
$\psi_3(1^3\!D_3)$. In our calculations, the instantaneous Bethe-Salpeter
method is applied to achieve the hadronic matrix elements. This method includes
relativistic corrections which are important especially for the higher orbital
excited states. For the semi-leptonic decay channels with electron as the final
lepton, we get the branching ratios $\mathcal{B}[B_c \rightarrow
\eta_{c2}e\bar{\nu}_e] = 5.9^{-0.8}_{+1.0}\times 10^{-4}$, $\mathcal{B}[B_c
\rightarrow \psi_2e\bar{\nu}_e]=1.5^{-0.2}_{+0.3}\times 10^{-4}$, and
$\mathcal{B}[B_c \rightarrow \psi_3e\bar{\nu}_e]=3.5^{-0.6}_{+0.8}\times
10^{-4}$. The transition form factors, forward-backward asymmetries, and lepton
spectra in these processes are also presented. For the non-leptonic decay
channels, those with $\rho$ as the lighter meson have the largest branching
ratios, $\mathcal{B}[B_c \rightarrow \eta_{c2}\rho] = 8.1^{-1.0}_{+1.0}\times
10^{-4}$, $\mathcal{B}[B_c \rightarrow \psi_2\rho]=9.6^{-1.0}_{+1.0}\times
10^{-5}$, and $\mathcal{B}[B_c \rightarrow \psi_3\rho]=4.1^{-0.7}_{+0.8}\times
10^{-4}$.
|
[
{
"created": "Mon, 7 Mar 2016 11:41:13 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Jun 2016 06:38:15 GMT",
"version": "v2"
},
{
"created": "Thu, 9 Jun 2016 11:38:59 GMT",
"version": "v3"
}
] |
2016-09-14
|
[
[
"Li",
"Qiang",
""
],
[
"Wang",
"Tianhong",
""
],
[
"Jiang",
"Yue",
""
],
[
"Yuan",
"Han",
""
],
[
"Wang",
"Guo-Li",
""
]
] |
We study the semi-leptonic and non-leptonic decays of $B_c$ meson to $D$-wave charmonia, namely, $\eta_{c2}(1^1\!D_2)$, $\psi_2(1^3\!D_2)$, and $\psi_3(1^3\!D_3)$. In our calculations, the instantaneous Bethe-Salpeter method is applied to achieve the hadronic matrix elements. This method includes relativistic corrections which are important especially for the higher orbital excited states. For the semi-leptonic decay channels with electron as the final lepton, we get the branching ratios $\mathcal{B}[B_c \rightarrow \eta_{c2}e\bar{\nu}_e] = 5.9^{-0.8}_{+1.0}\times 10^{-4}$, $\mathcal{B}[B_c \rightarrow \psi_2e\bar{\nu}_e]=1.5^{-0.2}_{+0.3}\times 10^{-4}$, and $\mathcal{B}[B_c \rightarrow \psi_3e\bar{\nu}_e]=3.5^{-0.6}_{+0.8}\times 10^{-4}$. The transition form factors, forward-backward asymmetries, and lepton spectra in these processes are also presented. For the non-leptonic decay channels, those with $\rho$ as the lighter meson have the largest branching ratios, $\mathcal{B}[B_c \rightarrow \eta_{c2}\rho] = 8.1^{-1.0}_{+1.0}\times 10^{-4}$, $\mathcal{B}[B_c \rightarrow \psi_2\rho]=9.6^{-1.0}_{+1.0}\times 10^{-5}$, and $\mathcal{B}[B_c \rightarrow \psi_3\rho]=4.1^{-0.7}_{+0.8}\times 10^{-4}$.
|
hep-ph/0001080
|
Eran Naftali
|
E. Gotsman, E. Levin, U. Maor and E. Naftali (Tel-Aviv U.)
|
The Components of the $\gamma^*\gamma^*$ Cross Section
|
28 pages, 12 Postscript figures
|
Eur.Phys.J.C14:511-523,2000
|
10.1007/s100520000362
|
TAUP 2618/00
|
hep-ph
| null |
We extend our previous treatment of $\gamma^*p$ cross section based on
Gribov's hypothesis to the case of photon-photon scattering. With the aid of
two parameters, determined from experimental data, we separate the interactions
into two categories corresponding to short ("soft") and long ("hard") distance
processes. The photon-photon cross section, thus, receives contributions from
three sectors, soft-soft, hard-hard and hard-soft. The additive quark model is
used to describe the soft-soft sector, pQCD the hard-hard sector, while the
hard-soft sector is determined by relating it to the $\gamma^{*}$p system. We
calculate and display the behaviour of the total photon-photon cross section
and it's various components and polarizations for different values of energy
and virtuality of the two photons, and discuss the significance of our results.
|
[
{
"created": "Tue, 11 Jan 2000 11:04:30 GMT",
"version": "v1"
}
] |
2011-09-13
|
[
[
"Gotsman",
"E.",
"",
"Tel-Aviv U."
],
[
"Levin",
"E.",
"",
"Tel-Aviv U."
],
[
"Maor",
"U.",
"",
"Tel-Aviv U."
],
[
"Naftali",
"E.",
"",
"Tel-Aviv U."
]
] |
We extend our previous treatment of $\gamma^*p$ cross section based on Gribov's hypothesis to the case of photon-photon scattering. With the aid of two parameters, determined from experimental data, we separate the interactions into two categories corresponding to short ("soft") and long ("hard") distance processes. The photon-photon cross section, thus, receives contributions from three sectors, soft-soft, hard-hard and hard-soft. The additive quark model is used to describe the soft-soft sector, pQCD the hard-hard sector, while the hard-soft sector is determined by relating it to the $\gamma^{*}$p system. We calculate and display the behaviour of the total photon-photon cross section and it's various components and polarizations for different values of energy and virtuality of the two photons, and discuss the significance of our results.
|
hep-ph/0309155
|
Arif Shoshi
|
H.-J. Pirner, A. I. Shoshi (Heidelberg University), G. Soyez
(Universite de Liege)
|
Log(1/x) Gluon Distribution and Structure Functions in the Loop-Loop
Correlation Model
|
13 pages, 10 figures,revised version,references added, typos
corrected, to be published in Eur. Phys. Journal C
|
Eur.Phys.J. C33 (2004) 63-74
|
10.1140/epjc/s2003-01528-2
| null |
hep-ph
| null |
We consider the interaction of the partonic fluctuation of a scalar
``photon'' with an external color field to calculate the leading and
next-to-leading order gluon distribution of the proton following the work done
by Dosch-Hebecker-Metz-Pirner. We relate these gluon distributions to the short
and long distance behavior of the cross section of an adjoint dipole scattering
off a proton. The leading order result is a constant while the next-to-leading
order result shows a ln(1/x) enhancement at small x. To get numerical results
for the gluon distributions at the initial scale Q^2_0=1.8 GeV^2, we compute
the adjoint dipole-proton cross section in the loop-loop correlation model.
Quark distributions at the same initial scale are parametrized according to
Regge theory. We evolve quark and gluon distributions to higher Q^2 values
using the DGLAP equation and compute charm and proton structure functions in
the small-x region for different Q^2 values.
|
[
{
"created": "Sun, 14 Sep 2003 12:53:54 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Dec 2003 17:54:07 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Pirner",
"H. -J.",
"",
"Heidelberg University"
],
[
"Shoshi",
"A. I.",
"",
"Heidelberg University"
],
[
"Soyez",
"G.",
"",
"Universite de Liege"
]
] |
We consider the interaction of the partonic fluctuation of a scalar ``photon'' with an external color field to calculate the leading and next-to-leading order gluon distribution of the proton following the work done by Dosch-Hebecker-Metz-Pirner. We relate these gluon distributions to the short and long distance behavior of the cross section of an adjoint dipole scattering off a proton. The leading order result is a constant while the next-to-leading order result shows a ln(1/x) enhancement at small x. To get numerical results for the gluon distributions at the initial scale Q^2_0=1.8 GeV^2, we compute the adjoint dipole-proton cross section in the loop-loop correlation model. Quark distributions at the same initial scale are parametrized according to Regge theory. We evolve quark and gluon distributions to higher Q^2 values using the DGLAP equation and compute charm and proton structure functions in the small-x region for different Q^2 values.
|
2003.06412
|
Emmanuel de Oliveira
|
Edgar Huayra, Emmanuel G. de Oliveira, Roman Pasechnik
|
DPS mechanism for associated $c\bar c b\bar b$ production in $AA$ UPCs
|
12 pages, 4 figs., version accepted for publication at EPJC
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss the associated $c\bar{c}$ and $b\bar{b}$ quark pairs production in
the double-parton scattering (DPS) process in ultraperipheral (UPCs) $AA$
collisions. We derive an analogue of the inclusive DPS pocket formula and the
photon-energy dependent effective cross section considering an overlap between
the hard SPS scatterings. We provide numerical predictions for the DPS cross
sections for the $c\bar{c}b\bar{b}$ production process at the typical energies
of $AA$ UPCs at the LHC and FCC colliders and also characterize the $A$
dependence of the total UPC DPS cross section.
|
[
{
"created": "Fri, 13 Mar 2020 17:54:02 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Aug 2020 20:16:44 GMT",
"version": "v2"
}
] |
2020-08-28
|
[
[
"Huayra",
"Edgar",
""
],
[
"de Oliveira",
"Emmanuel G.",
""
],
[
"Pasechnik",
"Roman",
""
]
] |
We discuss the associated $c\bar{c}$ and $b\bar{b}$ quark pairs production in the double-parton scattering (DPS) process in ultraperipheral (UPCs) $AA$ collisions. We derive an analogue of the inclusive DPS pocket formula and the photon-energy dependent effective cross section considering an overlap between the hard SPS scatterings. We provide numerical predictions for the DPS cross sections for the $c\bar{c}b\bar{b}$ production process at the typical energies of $AA$ UPCs at the LHC and FCC colliders and also characterize the $A$ dependence of the total UPC DPS cross section.
|
1310.2788
|
Anders Kvellestad
|
N.-E. Bomark, A. Kvellestad, S. Lola, P. Osland and A.R. Raklev
|
Long lived charginos in Natural SUSY?
|
Extended discussion, updated references, matches version to appear in
JHEP
| null |
10.1007/JHEP05(2014)007
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Supersymmetric models with a small neutralino-chargino mass difference, and
as a result metastable charginos, have been a popular topic of investigation in
collider phenomenology, e.g. in anomaly-mediated models of supersymmetry
breaking. Recently, the absence of any supersymmetric signal at the 8 TeV LHC
data has led to significant interest in the so-called Natural SUSY models with
light higgsinos. These models also have a naturally small neutralino-chargino
mass difference. However, we show here that when relevant indirect constraints
from results at the LHC and elsewhere are applied, this possibility is heavily
constrained within the Minimal Supersymmetric Standard Model (MSSM): massive
metastable higgsinos are not a signature of Natural SUSY.
|
[
{
"created": "Thu, 10 Oct 2013 12:28:49 GMT",
"version": "v1"
},
{
"created": "Sat, 3 May 2014 14:29:47 GMT",
"version": "v2"
}
] |
2015-06-17
|
[
[
"Bomark",
"N. -E.",
""
],
[
"Kvellestad",
"A.",
""
],
[
"Lola",
"S.",
""
],
[
"Osland",
"P.",
""
],
[
"Raklev",
"A. R.",
""
]
] |
Supersymmetric models with a small neutralino-chargino mass difference, and as a result metastable charginos, have been a popular topic of investigation in collider phenomenology, e.g. in anomaly-mediated models of supersymmetry breaking. Recently, the absence of any supersymmetric signal at the 8 TeV LHC data has led to significant interest in the so-called Natural SUSY models with light higgsinos. These models also have a naturally small neutralino-chargino mass difference. However, we show here that when relevant indirect constraints from results at the LHC and elsewhere are applied, this possibility is heavily constrained within the Minimal Supersymmetric Standard Model (MSSM): massive metastable higgsinos are not a signature of Natural SUSY.
|
hep-ph/9910310
|
Maxim Polyakov
|
B. Lehmann-Dronke, P.V. Pobylitsa, M.V. Polyakov, A. Schafer, and K.
Goeke
|
Hard diffractive electroproduction of two pions
|
Estimates of angular distributions are added
|
Phys.Lett. B475 (2000) 147-156
|
10.1016/S0370-2693(00)00069-1
|
RUB-TP2-16/98
|
hep-ph
| null |
We have calculated the leading order amplitude of hard diffractive
electroproduction of two pions in lepton nucleon scattering. At the leading
twist level a pion pair can be produced only in an isospin one or zero state.
We have shown that isoscalar states are produced dominantly for x_{Bj}>0.3 and
with an invariant mass of the two pions close to the threshold (S-wave) and in
the f_2 resonance region (D-wave). These isoscalar pion pairs are dominantly
produced by two collinear gluons.
Comparing the production of charged and neutral pion pairs as a function of
x_{Bj} and m_pipi one can get information about the gluonic component of
two-pion distribution amplitudes.
|
[
{
"created": "Tue, 12 Oct 1999 14:00:16 GMT",
"version": "v1"
},
{
"created": "Sun, 20 Feb 2000 13:26:34 GMT",
"version": "v2"
}
] |
2009-10-31
|
[
[
"Lehmann-Dronke",
"B.",
""
],
[
"Pobylitsa",
"P. V.",
""
],
[
"Polyakov",
"M. V.",
""
],
[
"Schafer",
"A.",
""
],
[
"Goeke",
"K.",
""
]
] |
We have calculated the leading order amplitude of hard diffractive electroproduction of two pions in lepton nucleon scattering. At the leading twist level a pion pair can be produced only in an isospin one or zero state. We have shown that isoscalar states are produced dominantly for x_{Bj}>0.3 and with an invariant mass of the two pions close to the threshold (S-wave) and in the f_2 resonance region (D-wave). These isoscalar pion pairs are dominantly produced by two collinear gluons. Comparing the production of charged and neutral pion pairs as a function of x_{Bj} and m_pipi one can get information about the gluonic component of two-pion distribution amplitudes.
|
hep-ph/9408377
|
Johannes Bluemlein
|
Johannes Bl\"umlein
|
Small $x$ Contributions to the Structure Function $F_L(x,Q^2)$
|
4 p., postscript encoded with uufiles; DESY 94--149
|
Nucl.Phys.Proc.Suppl. 39BC (1995) 22-24
|
10.1016/0920-5632(95)00035-8
| null |
hep-ph
| null |
The gluon contributions to $F_L(x,Q^2)$ in ${\cal O}(\alpha_s)$ are
calculated taking into account the transverse momentum of the initial state
parton. In comparison with collinear factorization $F_L(x,Q^2)$, is not
affected at large $x$ but takes smaller values in the small $x$ range. The
onset of the $k_{\perp}$ effect is a function of $Q^2$.
|
[
{
"created": "Fri, 26 Aug 1994 08:45:27 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Blümlein",
"Johannes",
""
]
] |
The gluon contributions to $F_L(x,Q^2)$ in ${\cal O}(\alpha_s)$ are calculated taking into account the transverse momentum of the initial state parton. In comparison with collinear factorization $F_L(x,Q^2)$, is not affected at large $x$ but takes smaller values in the small $x$ range. The onset of the $k_{\perp}$ effect is a function of $Q^2$.
|
2004.05174
|
Oscar J. P. \'Eboli
|
Eduardo da Silva Almeida, O. J. P. \'Eboli, M. C. Gonzalez-Garcia
|
Unitarity Constraints on Anomalous Quartic Couplings
|
typos corrected and two additional operators included in the analyses
|
Phys. Rev. D 101, 113003 (2020)
|
10.1103/PhysRevD.101.113003
|
YITP-SB-2020-8
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We obtain the partial-wave unitarity constraints on the lowest-dimension
effective operators which generate anomalous quartic gauge couplings but leave
the triple gauge couplings unaffected. We consider operator expansions with
linear and nonlinear realizations of the electroweak symmetry and explore the
multidimensional parameter space of the coefficients of the relevant operators:
20 dimension-eight operators in the linear expansion and 5 ${\cal O}(p^4)$
operators in the derivative expansion. We study two-to-two scattering of
electroweak gauge bosons and Higgs bosons taking into account all coupled
channels and all possible helicity amplitudes for the $J=0,1$ partial waves. In
general, the bounds degrade by factors of a few when several operator
coefficients are considered non-vanishing simultaneously. However, this
requires to consider constraints from both $J=0$ and $J=1$ partial waves for
some sets of operators.
|
[
{
"created": "Fri, 10 Apr 2020 18:00:02 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Jun 2020 14:42:27 GMT",
"version": "v2"
},
{
"created": "Thu, 18 Mar 2021 14:29:06 GMT",
"version": "v3"
}
] |
2021-03-19
|
[
[
"Almeida",
"Eduardo da Silva",
""
],
[
"Éboli",
"O. J. P.",
""
],
[
"Gonzalez-Garcia",
"M. C.",
""
]
] |
We obtain the partial-wave unitarity constraints on the lowest-dimension effective operators which generate anomalous quartic gauge couplings but leave the triple gauge couplings unaffected. We consider operator expansions with linear and nonlinear realizations of the electroweak symmetry and explore the multidimensional parameter space of the coefficients of the relevant operators: 20 dimension-eight operators in the linear expansion and 5 ${\cal O}(p^4)$ operators in the derivative expansion. We study two-to-two scattering of electroweak gauge bosons and Higgs bosons taking into account all coupled channels and all possible helicity amplitudes for the $J=0,1$ partial waves. In general, the bounds degrade by factors of a few when several operator coefficients are considered non-vanishing simultaneously. However, this requires to consider constraints from both $J=0$ and $J=1$ partial waves for some sets of operators.
|
0911.3571
|
Nils-Erik Bomark
|
N.-E. Bomark, S. Lola, P. Osland, A.R. Raklev
|
Cosmic Ray Signatures from Decaying Gravitino Dark Matter
|
To appear in the proceedings of EPS-HEP 2009, Krakow, Poland
|
PoS EPS-HEP2009:098,2009
| null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the charged cosmic rays arising from the slow decay of gravitino
dark matter within supersymmetric scenarios with trilinear R-parity violation.
It is shown that operators of the LLE type can very well account for the recent
anomalies in cosmic ray electron and positron data reported by PAMELA, ATIC and
Fermi LAT, without violating any other bounds. This scenario will soon be
tested by the Fermi LAT data on diffuse gamma ray emission.
|
[
{
"created": "Wed, 18 Nov 2009 15:26:55 GMT",
"version": "v1"
}
] |
2014-11-20
|
[
[
"Bomark",
"N. -E.",
""
],
[
"Lola",
"S.",
""
],
[
"Osland",
"P.",
""
],
[
"Raklev",
"A. R.",
""
]
] |
We study the charged cosmic rays arising from the slow decay of gravitino dark matter within supersymmetric scenarios with trilinear R-parity violation. It is shown that operators of the LLE type can very well account for the recent anomalies in cosmic ray electron and positron data reported by PAMELA, ATIC and Fermi LAT, without violating any other bounds. This scenario will soon be tested by the Fermi LAT data on diffuse gamma ray emission.
|
0711.4993
|
Silvia Pascoli
|
S. Pascoli and S. T. Petcov
|
Majorana Neutrinos, Neutrino Mass Spectrum and the |<m>| ~ 0.001 eV
Frontier in Neutrinoless Double Beta Decay
|
29 pages, 6 eps figures
|
Phys.Rev.D77:113003,2008
|
10.1103/PhysRevD.77.113003
|
SISSA 78/2007/EP; IPPP/07/83; CPT/07/166
|
hep-ph
| null |
If future neutrino oscillation experiments show that the neutrino mass
spectrum is with normal ordering, m1 < m2 < m3, and the searches for
neutrinoless double beta-decay with sensitivity to values of the effective
Majorana mass |<m>| > 0.01 eV give negative results, the next frontier in the
quest for neutrinoless double beta-decay will correspond to |<m>| ~ 0.001 eV.
Assuming that massive neutrinos are Majorana particles and their exchange is
the dominant mechanism generating neutrinoless double beta-decay, we analise
the conditions under which |<m>|, in the case of three neutrino mixing and
neutrino mass spectrum with normal ordering, would satisfy |<m>| > 0.001 eV. We
consider the specific cases of i) normal hierarchical neutrino mass spectrum,
ii) of relatively small value of the CHOOZ angle theta13 as well as iii) the
general case of spectrum with normal ordering, partial hierarchy and a value of
theta13 close to the existing upper limit. We study the ranges of the lightest
neutrino mass m1 and/or of sin^2 theta13, for which |<m>|> 0.001 eV and discuss
the phenomenological implications of such scenarios. We provide also an
estimate of |<m>| when the three neutrino masses and the neutrino mixing
originate from neutrino mass term of Majorana type for the (left-handed)
flavour neutrinos and m1 Ue1^2 + m2 U_e2^2 + m3 Ue3^2 =0, but there does not
exist a symmetry which forbids the neutrinoless double beta-decay.
|
[
{
"created": "Fri, 30 Nov 2007 17:57:45 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Pascoli",
"S.",
""
],
[
"Petcov",
"S. T.",
""
]
] |
If future neutrino oscillation experiments show that the neutrino mass spectrum is with normal ordering, m1 < m2 < m3, and the searches for neutrinoless double beta-decay with sensitivity to values of the effective Majorana mass |<m>| > 0.01 eV give negative results, the next frontier in the quest for neutrinoless double beta-decay will correspond to |<m>| ~ 0.001 eV. Assuming that massive neutrinos are Majorana particles and their exchange is the dominant mechanism generating neutrinoless double beta-decay, we analise the conditions under which |<m>|, in the case of three neutrino mixing and neutrino mass spectrum with normal ordering, would satisfy |<m>| > 0.001 eV. We consider the specific cases of i) normal hierarchical neutrino mass spectrum, ii) of relatively small value of the CHOOZ angle theta13 as well as iii) the general case of spectrum with normal ordering, partial hierarchy and a value of theta13 close to the existing upper limit. We study the ranges of the lightest neutrino mass m1 and/or of sin^2 theta13, for which |<m>|> 0.001 eV and discuss the phenomenological implications of such scenarios. We provide also an estimate of |<m>| when the three neutrino masses and the neutrino mixing originate from neutrino mass term of Majorana type for the (left-handed) flavour neutrinos and m1 Ue1^2 + m2 U_e2^2 + m3 Ue3^2 =0, but there does not exist a symmetry which forbids the neutrinoless double beta-decay.
|
1804.07255
|
Mark Hertzberg
|
Mark P. Hertzberg, Enrico D. Schiappacasse
|
Scalar Dark Matter Clumps with Angular Momentum
|
22 pages, 7 figures. V2: Additional comparison to literature and
added references. Updated to resemble version published in JCAP
|
JCAP 08 (2018) 028
|
10.1088/1475-7516/2018/08/028
| null |
hep-ph astro-ph.CO astro-ph.GA gr-qc hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The behavior of light scalar dark matter has been a subject of much interest
recently as it can lead to interesting small scale behavior. In particular,
this can lead to the formation of gravitationally bound clumps for these light
scalars, including axions. In Ref. [1] we analyzed the behavior of these
clumps, assuming spherical symmetry, allowing for both attractive and repulsive
self-interactions. There is a maximum allowed mass for the clumps in the case
of attractive interactions, and a minimum radius for the clumps in the case of
repulsive interactions, which is saturated at large mass. Here we extend this
work to include non-spherically symmetric clumps. Since the system tries to
re-organize into a BEC ground state, we consider configurations with a
conserved non-zero angular momentum, and construct minimum energy
configurations at fixed particle number and fixed angular momentum. We find
generalizations of the previous spherically symmetric results. In particular,
while there is still a maximum mass for the attractive case, its value
increases with angular momentum. Also, the minimum radius in the repulsive case
is raised to higher radii. We clarify how a recent claim in the literature of
an upper bound on angular momentum is due to inaccurate numerics. In a
forthcoming paper we shall investigate the possibility of resonance of axion
clumps into both visible and hidden sector photons, and analyze how the altered
mass and radius from non-zero angular momentum affects the resonance.
|
[
{
"created": "Thu, 19 Apr 2018 16:23:23 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Sep 2018 17:47:53 GMT",
"version": "v2"
}
] |
2018-09-18
|
[
[
"Hertzberg",
"Mark P.",
""
],
[
"Schiappacasse",
"Enrico D.",
""
]
] |
The behavior of light scalar dark matter has been a subject of much interest recently as it can lead to interesting small scale behavior. In particular, this can lead to the formation of gravitationally bound clumps for these light scalars, including axions. In Ref. [1] we analyzed the behavior of these clumps, assuming spherical symmetry, allowing for both attractive and repulsive self-interactions. There is a maximum allowed mass for the clumps in the case of attractive interactions, and a minimum radius for the clumps in the case of repulsive interactions, which is saturated at large mass. Here we extend this work to include non-spherically symmetric clumps. Since the system tries to re-organize into a BEC ground state, we consider configurations with a conserved non-zero angular momentum, and construct minimum energy configurations at fixed particle number and fixed angular momentum. We find generalizations of the previous spherically symmetric results. In particular, while there is still a maximum mass for the attractive case, its value increases with angular momentum. Also, the minimum radius in the repulsive case is raised to higher radii. We clarify how a recent claim in the literature of an upper bound on angular momentum is due to inaccurate numerics. In a forthcoming paper we shall investigate the possibility of resonance of axion clumps into both visible and hidden sector photons, and analyze how the altered mass and radius from non-zero angular momentum affects the resonance.
|
1601.06557
|
Bertrand Duclou\'e
|
B. Duclou\'e, T. Lappi, H. M\"antysaari
|
Centrality-dependent forward $J/\psi$ production in high energy
proton-nucleus collisions
|
6 pages, 2 figures. Contribution to the proceedings of the 6th
International Conference on Physics Opportunities at an Electron-Ion Collider
(POETIC6), September 7-11, 2015, Palaiseau, France
| null |
10.1051/epjconf/201611204002
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Forward $J/\psi$ production and suppression in high energy proton-nucleus
collisions can be an important probe of gluon saturation. In an earlier work we
studied this process in the Color Glass Condensate framework and showed that
using the Glauber approach to extrapolate the dipole cross section of a proton
to a nucleus leads to results closer to experimental data than previous
calculations in this framework. Here we investigate the centrality dependence
of the nuclear suppression in this model and show a comparison of our results
with recent LHC data.
|
[
{
"created": "Mon, 25 Jan 2016 11:21:31 GMT",
"version": "v1"
}
] |
2016-04-20
|
[
[
"Ducloué",
"B.",
""
],
[
"Lappi",
"T.",
""
],
[
"Mäntysaari",
"H.",
""
]
] |
Forward $J/\psi$ production and suppression in high energy proton-nucleus collisions can be an important probe of gluon saturation. In an earlier work we studied this process in the Color Glass Condensate framework and showed that using the Glauber approach to extrapolate the dipole cross section of a proton to a nucleus leads to results closer to experimental data than previous calculations in this framework. Here we investigate the centrality dependence of the nuclear suppression in this model and show a comparison of our results with recent LHC data.
|
hep-ph/0603250
|
Irinel Caprini
|
Irinel Caprini
|
Rescattering effects and the $\sigma$ pole in hadronic decays
|
10 pages, minor text changes, version to appear in Phys.Lett.B
|
Phys.Lett.B638:468-472,2006
|
10.1016/j.physletb.2006.06.003
| null |
hep-ph
| null |
The $\sigma$ resonance was observed as a conspicuous $\pi^+\pi^-$ peak in
hadronic decays like $J/\psi\to \pi^+\pi^-\omega$ or $D^+\to\pi^+\pi^-\pi^+$.
The phase of the $\sigma\to\pi^+\pi^-$ amplitude, extracted from production
data within the conventional isobar model, is assumed to coincide with that in
$\pi\pi$ elastic scattering. We check the validity of this assumption by using
Lehmann-Symanzik-Zimmermann (LSZ) reduction and unitarity. The rescattering
effects in the final three-particle states are shown to generate a correction
to the phase given by a naive application of Watson theorem. We briefly discuss
the implications of this result for the pole determination from production
data.
|
[
{
"created": "Thu, 30 Mar 2006 07:20:17 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Jun 2006 08:54:54 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Caprini",
"Irinel",
""
]
] |
The $\sigma$ resonance was observed as a conspicuous $\pi^+\pi^-$ peak in hadronic decays like $J/\psi\to \pi^+\pi^-\omega$ or $D^+\to\pi^+\pi^-\pi^+$. The phase of the $\sigma\to\pi^+\pi^-$ amplitude, extracted from production data within the conventional isobar model, is assumed to coincide with that in $\pi\pi$ elastic scattering. We check the validity of this assumption by using Lehmann-Symanzik-Zimmermann (LSZ) reduction and unitarity. The rescattering effects in the final three-particle states are shown to generate a correction to the phase given by a naive application of Watson theorem. We briefly discuss the implications of this result for the pole determination from production data.
|
2107.02652
|
Glen Cowan
|
Glen Cowan
|
Effect of Systematic Uncertainty Estimation on the Muon $g-2$ Anomaly
|
6 pages, 2 figures
| null |
10.1051/epjconf/202225809002
| null |
hep-ph physics.data-an
|
http://creativecommons.org/licenses/by/4.0/
|
The statistical significance that characterizes a discrepancy between a
measurement and theoretical prediction is usually calculated assuming that the
statistical and systematic uncertainties are known. Many types of systematic
uncertainties are, however, estimated on the basis of approximate procedures
and thus the values of the assigned errors are themselves uncertain. Here the
impact of the uncertainty {\it on the assigned uncertainty} is investigated in
the context of the muon $g-2$ anomaly. The significance of the observed
discrepancy between the Standard Model prediction of the muon's anomalous
magnetic moment and measured values are shown to decrease substantially if the
relative uncertainty in the uncertainty assigned to the Standard Model
prediction exceeds around 30\%. The reduction in sensitivity increases for
higher significance, so that establishing a $5\sigma$ effect will require not
only small uncertainties but the uncertainties themselves must be estimated
accurately to correspond to one standard deviation.
|
[
{
"created": "Tue, 6 Jul 2021 14:43:57 GMT",
"version": "v1"
}
] |
2022-02-16
|
[
[
"Cowan",
"Glen",
""
]
] |
The statistical significance that characterizes a discrepancy between a measurement and theoretical prediction is usually calculated assuming that the statistical and systematic uncertainties are known. Many types of systematic uncertainties are, however, estimated on the basis of approximate procedures and thus the values of the assigned errors are themselves uncertain. Here the impact of the uncertainty {\it on the assigned uncertainty} is investigated in the context of the muon $g-2$ anomaly. The significance of the observed discrepancy between the Standard Model prediction of the muon's anomalous magnetic moment and measured values are shown to decrease substantially if the relative uncertainty in the uncertainty assigned to the Standard Model prediction exceeds around 30\%. The reduction in sensitivity increases for higher significance, so that establishing a $5\sigma$ effect will require not only small uncertainties but the uncertainties themselves must be estimated accurately to correspond to one standard deviation.
|
1704.05893
|
Bob Holdom
|
Bob Holdom and Roman Koniuk
|
A bound state model for a light scalar
|
14 pages, 8 figures, published version
|
J. High Energ. Phys. (2017) 2017: 102
|
10.1007/JHEP12(2017)102
| null |
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Recent lattice studies of near-conformal strong dynamics suggest the
existence of a light scalar. This provides motivation to consider a simple
Hamiltonian-based bound-state model where the pseudoscalar, scalar, vector and
axial-vector states are treated on an equal footing. The model interpolates
between the non-relativistic limit and the highly relativistic chiral limit,
where the pseudoscalar mass drops to zero. The fermion mass becomes purely
dynamical at this point. When the gauge coupling is constant over a moderate
range of scales the scalar becomes significantly lighter than the spin 1 states
as the chiral limit is approached. We relate this result to the behavior of the
form factors of the respective states and their decay constants. In the
conformal limit of the model all masses vanish and the theory is characterized
by scaling dimensions.
|
[
{
"created": "Wed, 19 Apr 2017 18:39:57 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Dec 2017 23:01:23 GMT",
"version": "v2"
}
] |
2017-12-22
|
[
[
"Holdom",
"Bob",
""
],
[
"Koniuk",
"Roman",
""
]
] |
Recent lattice studies of near-conformal strong dynamics suggest the existence of a light scalar. This provides motivation to consider a simple Hamiltonian-based bound-state model where the pseudoscalar, scalar, vector and axial-vector states are treated on an equal footing. The model interpolates between the non-relativistic limit and the highly relativistic chiral limit, where the pseudoscalar mass drops to zero. The fermion mass becomes purely dynamical at this point. When the gauge coupling is constant over a moderate range of scales the scalar becomes significantly lighter than the spin 1 states as the chiral limit is approached. We relate this result to the behavior of the form factors of the respective states and their decay constants. In the conformal limit of the model all masses vanish and the theory is characterized by scaling dimensions.
|
1110.4138
|
Vincenzo Greco
|
V. Greco (Catania U.), H. van Hees (Frankfurt U.), R. Rapp (Texas A&M
U.)
|
Heavy Quark Dynamics in the QGP
|
10 pages, 4 figures, Proceedings of EPIC@LHC Workshop, 6-8 July, Bari
| null |
10.1063/1.3692206
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We assess transport properties of heavy quarks in the Quark-Gluon Plasma
(QGP) that show a strong non-perturbative behavior. A T-matrix approach based
on a potential taken from lattice QCD hints at the presence of heavy-quark (HQ)
resonant scattering with an increasing strength as the temperature, $T$,
reaches the critical temperature, $T_c \simeq 170 \; \MeV$ for deconfinement
from above. The implementation of HQ resonance scattering along with a
hadronization via quark coalescence under the conditions of the plasma created
in heavy-ion collisions has been shown to correctly describe both the nuclear
modification factor, $R_{AA}$, and the elliptic flow, $v_2$, of single
electrons at RHIC and have correctly predicted the $R_{AA}$ of D mesons at LHC
energy.
|
[
{
"created": "Tue, 18 Oct 2011 22:27:27 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Oct 2011 09:01:43 GMT",
"version": "v2"
}
] |
2015-05-30
|
[
[
"Greco",
"V.",
"",
"Catania U."
],
[
"van Hees",
"H.",
"",
"Frankfurt U."
],
[
"Rapp",
"R.",
"",
"Texas A&M\n U."
]
] |
We assess transport properties of heavy quarks in the Quark-Gluon Plasma (QGP) that show a strong non-perturbative behavior. A T-matrix approach based on a potential taken from lattice QCD hints at the presence of heavy-quark (HQ) resonant scattering with an increasing strength as the temperature, $T$, reaches the critical temperature, $T_c \simeq 170 \; \MeV$ for deconfinement from above. The implementation of HQ resonance scattering along with a hadronization via quark coalescence under the conditions of the plasma created in heavy-ion collisions has been shown to correctly describe both the nuclear modification factor, $R_{AA}$, and the elliptic flow, $v_2$, of single electrons at RHIC and have correctly predicted the $R_{AA}$ of D mesons at LHC energy.
|
1902.05142
|
Jens Erler
|
Jens Erler and Matthias Schott
|
Electroweak Precision Tests of the Standard Model after the Discovery of
the Higgs Boson
|
65 pages, 52 figures
| null |
10.1016/j.ppnp.2019.02.007
|
MITP/19-006
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The global fit of the Standard Model predictions to electroweak precision
data, which has been routinely performed in the past decades by several groups,
led to the prediction of the top quark and the Higgs boson masses before their
respective discoveries. With the measurement of the Higgs boson mass at the
Large Hadron Collider (LHC) in 2012 by the ATLAS and CMS collaborations, the
last free parameter of the Standard Model of particle physics has been fixed,
and the global electroweak fit can be used to test the full internal
consistency of the electroweak sector of the Standard Model and constrain
models beyond. In this article, we review the current state-of-the-art
theoretical calculations, as well as the precision measurements performed at
the LHC, and interpret them within the context of the global electroweak fit.
Special focus is drawn in the impact of the Higgs boson mass on the fit.
|
[
{
"created": "Wed, 13 Feb 2019 21:50:03 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Feb 2019 12:03:29 GMT",
"version": "v2"
}
] |
2019-05-01
|
[
[
"Erler",
"Jens",
""
],
[
"Schott",
"Matthias",
""
]
] |
The global fit of the Standard Model predictions to electroweak precision data, which has been routinely performed in the past decades by several groups, led to the prediction of the top quark and the Higgs boson masses before their respective discoveries. With the measurement of the Higgs boson mass at the Large Hadron Collider (LHC) in 2012 by the ATLAS and CMS collaborations, the last free parameter of the Standard Model of particle physics has been fixed, and the global electroweak fit can be used to test the full internal consistency of the electroweak sector of the Standard Model and constrain models beyond. In this article, we review the current state-of-the-art theoretical calculations, as well as the precision measurements performed at the LHC, and interpret them within the context of the global electroweak fit. Special focus is drawn in the impact of the Higgs boson mass on the fit.
|
hep-ph/9406285
|
Claudio Lucchesi
|
P.F. Kelly, Q. Liu, C. Lucchesi and C. Manuel
|
Classical Transport Theory and Hard Thermal Loops in the Quark-Gluon
Plasma
|
MIT--CTP #2320, 23 pages, Revtex
|
Phys.Rev.D50:4209-4218,1994
|
10.1103/PhysRevD.50.4209
| null |
hep-ph hep-th nucl-th
| null |
Classical transport theory for colored particles is investigated and employed
to derive the hard thermal loops of QCD. A formal construction of phase-space
for color degrees of freedom is presented. The gauge invariance of the
non-Abelian Vlasov equations is verified and used as a guiding principle in our
approximation scheme.We then derive the generating functional of hard thermal
loops from a constraint satisfied at leading-order by the color current. This
derivation is more direct than alternative ones based on perturbative quantum
field theory, and shows that hard thermal effects in hot QCD are essentially
{\it classical}. As an illustration, we analyze color polarization in the QCD
plasma.
|
[
{
"created": "Fri, 10 Jun 1994 20:23:53 GMT",
"version": "v1"
}
] |
2011-07-19
|
[
[
"Kelly",
"P. F.",
""
],
[
"Liu",
"Q.",
""
],
[
"Lucchesi",
"C.",
""
],
[
"Manuel",
"C.",
""
]
] |
Classical transport theory for colored particles is investigated and employed to derive the hard thermal loops of QCD. A formal construction of phase-space for color degrees of freedom is presented. The gauge invariance of the non-Abelian Vlasov equations is verified and used as a guiding principle in our approximation scheme.We then derive the generating functional of hard thermal loops from a constraint satisfied at leading-order by the color current. This derivation is more direct than alternative ones based on perturbative quantum field theory, and shows that hard thermal effects in hot QCD are essentially {\it classical}. As an illustration, we analyze color polarization in the QCD plasma.
|
1909.03554
|
Yan-Qing Ma
|
Rong Li, An-Ping Chen, Jing-Kai Huang, Yan-Qing Ma
|
Relativistic effect of $J/\psi$ hadroproduction in large $p_T$ region
|
24 pages, 2 figures
| null |
10.1007/JHEP10(2019)210
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
By combining NRQCD factorization and collinear factorization, we compute a
series of relativistic corrections for $J/\psi$ hadroproduction to all orders
in $v^2$ at large $p_T$ limit. The $v^2$ expansion converges well for all
channels. We find that the ratio of relativistic correction term to the
corresponding leading term is independent of kinematic variables for any
channel, which generalizes the proportional relations found in previous works
to all orders.
|
[
{
"created": "Sun, 8 Sep 2019 22:05:44 GMT",
"version": "v1"
}
] |
2020-01-08
|
[
[
"Li",
"Rong",
""
],
[
"Chen",
"An-Ping",
""
],
[
"Huang",
"Jing-Kai",
""
],
[
"Ma",
"Yan-Qing",
""
]
] |
By combining NRQCD factorization and collinear factorization, we compute a series of relativistic corrections for $J/\psi$ hadroproduction to all orders in $v^2$ at large $p_T$ limit. The $v^2$ expansion converges well for all channels. We find that the ratio of relativistic correction term to the corresponding leading term is independent of kinematic variables for any channel, which generalizes the proportional relations found in previous works to all orders.
|
2102.06718
|
Matthew Schwartz
|
Roman N. Lee, Matthew D. Schwartz, and Xiaoyuan Zhang
|
The Compton Scattering Total Cross Section at Next-to-Leading Order
|
6 pages 1 figure; v2. published version; explicit expressions given
in an Appendix and in Mathematica notebook
|
Phys. Rev. Lett. 126, 211801 (2021)
|
10.1103/PhysRevLett.126.211801
| null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
An analytic formula is given for the total scattering cross section of an
electron and a photon at order $\alpha^3$. This includes both the
double-Compton scattering real-emission contribution as well as the virtual
Compton scattering part. When combined with the recent analytic result for the
pair-production cross section, the complete $\alpha^3$ cross section is now
known. Both the next-to-leading order calculation as well as the
pair-production cross section are computed using modern multiloop calculation
techniques, where cut diagrams are decomposed into a set of master integrals
that are then computed using differential equations.
|
[
{
"created": "Fri, 12 Feb 2021 19:00:11 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Jun 2021 18:23:18 GMT",
"version": "v2"
}
] |
2021-06-18
|
[
[
"Lee",
"Roman N.",
""
],
[
"Schwartz",
"Matthew D.",
""
],
[
"Zhang",
"Xiaoyuan",
""
]
] |
An analytic formula is given for the total scattering cross section of an electron and a photon at order $\alpha^3$. This includes both the double-Compton scattering real-emission contribution as well as the virtual Compton scattering part. When combined with the recent analytic result for the pair-production cross section, the complete $\alpha^3$ cross section is now known. Both the next-to-leading order calculation as well as the pair-production cross section are computed using modern multiloop calculation techniques, where cut diagrams are decomposed into a set of master integrals that are then computed using differential equations.
|
1112.6086
|
Takahiro Sasaki
|
Takahiro Sasaki, Junichi Takahashi, Yuji Sakai, Hiroaki Kouno,
Masanobu Yahiro
|
Theta vacuum and entanglement interaction in the three-flavor
Polyakov-loop extended Nambu-Jona-Lasinio model
|
9 pages, 14 figures, Published version
|
Phys.Rev.D85:056009,2012
|
10.1103/PhysRevD.85.056009
| null |
hep-ph hep-lat nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate theta-vacuum effects on the QCD phase diagram for the
realistic 2+1 flavor system, using the three-flavor Polyakov-extended
Nambu-Jona-Lasinio (PNJL) model and the entanglement PNJL model as an extension
of the PNJL model. The theta-vacuum effects make the chiral transition sharper.
For large theta-vacuum angle the chiral transition becomes first order even if
the quark number chemical potential is zero, when the entanglement coupling
between the chiral condensate and the Polyakov loop is taken into account. We
finally propose a way of circumventing the sign problem on lattice QCD with
finite theta.
|
[
{
"created": "Wed, 28 Dec 2011 09:53:50 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Feb 2012 10:47:11 GMT",
"version": "v2"
},
{
"created": "Thu, 5 Apr 2012 05:44:28 GMT",
"version": "v3"
}
] |
2012-04-06
|
[
[
"Sasaki",
"Takahiro",
""
],
[
"Takahashi",
"Junichi",
""
],
[
"Sakai",
"Yuji",
""
],
[
"Kouno",
"Hiroaki",
""
],
[
"Yahiro",
"Masanobu",
""
]
] |
We investigate theta-vacuum effects on the QCD phase diagram for the realistic 2+1 flavor system, using the three-flavor Polyakov-extended Nambu-Jona-Lasinio (PNJL) model and the entanglement PNJL model as an extension of the PNJL model. The theta-vacuum effects make the chiral transition sharper. For large theta-vacuum angle the chiral transition becomes first order even if the quark number chemical potential is zero, when the entanglement coupling between the chiral condensate and the Polyakov loop is taken into account. We finally propose a way of circumventing the sign problem on lattice QCD with finite theta.
|
2201.02317
|
Mikko Laine
|
P. Klose, M. Laine, S. Procacci
|
Gravitational wave background from non-Abelian reheating after
axion-like inflation
|
18 pages. v2: clarifications added
|
JCAP 05 (2022) 021
|
10.1088/1475-7516/2022/05/021
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A pseudoscalar inflaton $\varphi$, coupled to the topological charge density
$F\tilde{F}$ of a non-Abelian sector, can decay to gauge bosons ($\varphi\to g
g $), which may thermalize rapidly. The friction felt by $\varphi$ is then
increased by non-Abelian "strong sphalerons", leading to a self-amplifying
process that can efficiently heat up the medium. We determine a lower bound for
the gravitational wave production rate from such a process, originating via
hydrodynamic fluctuations and particle collisions, in terms of a minimal number
of parameters. Only a moderate fraction of energy density is converted to
gravitational waves, suggesting that non-Abelian models may avoid the
overproduction observed in some Abelian cases.
|
[
{
"created": "Fri, 7 Jan 2022 03:54:18 GMT",
"version": "v1"
},
{
"created": "Fri, 13 May 2022 15:57:35 GMT",
"version": "v2"
}
] |
2022-05-16
|
[
[
"Klose",
"P.",
""
],
[
"Laine",
"M.",
""
],
[
"Procacci",
"S.",
""
]
] |
A pseudoscalar inflaton $\varphi$, coupled to the topological charge density $F\tilde{F}$ of a non-Abelian sector, can decay to gauge bosons ($\varphi\to g g $), which may thermalize rapidly. The friction felt by $\varphi$ is then increased by non-Abelian "strong sphalerons", leading to a self-amplifying process that can efficiently heat up the medium. We determine a lower bound for the gravitational wave production rate from such a process, originating via hydrodynamic fluctuations and particle collisions, in terms of a minimal number of parameters. Only a moderate fraction of energy density is converted to gravitational waves, suggesting that non-Abelian models may avoid the overproduction observed in some Abelian cases.
|
1409.2494
|
Hongxi Xing
|
Zhong-Bo Kang, Ivan Vitev, Enke Wang, Hongxi Xing, Cheng Zhang
|
Multiple scattering effects on heavy meson production in p+A collisions
at backward rapidity
|
10 pages, 6 figures, published version in PLB
|
Phys. Lett. B 740, 23 (2015)
|
10.1016/j.physletb.2014.11.024
|
LA-UR-14-27010
|
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the incoherent multiple scattering effects on heavy meson production
in the backward rapidity region of p+A collisions within the generalized
high-twist factorization formalism. We calculate explicitly the double
scattering contributions to the heavy meson differential cross sections by
taking into account both initial-state and final-state interactions, and find
that these corrections are positive. We further evaluate the nuclear
modification factor for muons that come form the semi-leptonic decays of heavy
flavor mesons. Phenomenological applications in d+Au collisions at a
center-of-mass energy $\sqrt{s}=200$ GeV at RHIC and in p+Pb collisions at
$\sqrt{s}=5.02$ TeV at the LHC are presented. We find that incoherent multiple
scattering can describe rather well the observed nuclear enhancement in the
intermediate $p_T$ region for such reactions.
|
[
{
"created": "Mon, 8 Sep 2014 20:00:10 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Dec 2014 23:30:40 GMT",
"version": "v2"
}
] |
2015-03-09
|
[
[
"Kang",
"Zhong-Bo",
""
],
[
"Vitev",
"Ivan",
""
],
[
"Wang",
"Enke",
""
],
[
"Xing",
"Hongxi",
""
],
[
"Zhang",
"Cheng",
""
]
] |
We study the incoherent multiple scattering effects on heavy meson production in the backward rapidity region of p+A collisions within the generalized high-twist factorization formalism. We calculate explicitly the double scattering contributions to the heavy meson differential cross sections by taking into account both initial-state and final-state interactions, and find that these corrections are positive. We further evaluate the nuclear modification factor for muons that come form the semi-leptonic decays of heavy flavor mesons. Phenomenological applications in d+Au collisions at a center-of-mass energy $\sqrt{s}=200$ GeV at RHIC and in p+Pb collisions at $\sqrt{s}=5.02$ TeV at the LHC are presented. We find that incoherent multiple scattering can describe rather well the observed nuclear enhancement in the intermediate $p_T$ region for such reactions.
|
0801.3124
|
Yutaka Tobita
|
Kenzo Ishikawa, Yutaka Tobita
|
Coherence length of cosmic background radiation enlarges the attenuation
length of the ultra-high energy proton
|
8 pages, 2 figures,study about the second coherence length has been
added
| null | null |
EPHOU-08-001
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
It is pointed out that an agreement of the one particle energy spectrum of
the cosmic background radiation (CMBR) with Plank distribution of 2.725 [K]
does not give a strong constraint on the coherence length of CMBR if the mean
free path of CMBR is very long. The coherence length in this situation is
estimated as a few times of $k_BT$. Due to this finite coherence length, the
attenuation length of ultra-high energy cosmic rays (UHECR) is reduced in the
$\Delta $ resonance region,i.e., around $10^{20}$ [eV]. The small attenuation
length makes the suppression of the flux of cosmic rays in this energy region
less prominent than the naive estimation
|
[
{
"created": "Mon, 21 Jan 2008 04:54:50 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Jun 2009 16:28:19 GMT",
"version": "v2"
},
{
"created": "Tue, 9 Mar 2010 10:14:26 GMT",
"version": "v3"
}
] |
2010-03-10
|
[
[
"Ishikawa",
"Kenzo",
""
],
[
"Tobita",
"Yutaka",
""
]
] |
It is pointed out that an agreement of the one particle energy spectrum of the cosmic background radiation (CMBR) with Plank distribution of 2.725 [K] does not give a strong constraint on the coherence length of CMBR if the mean free path of CMBR is very long. The coherence length in this situation is estimated as a few times of $k_BT$. Due to this finite coherence length, the attenuation length of ultra-high energy cosmic rays (UHECR) is reduced in the $\Delta $ resonance region,i.e., around $10^{20}$ [eV]. The small attenuation length makes the suppression of the flux of cosmic rays in this energy region less prominent than the naive estimation
|
hep-ph/0112065
|
Gilberto Tavares Velasco
|
A. Flores-Tlalpa, J. M. Hernandez, G. Tavares-Velasco and J.J. Toscano
|
Effective Lagrangian description of the lepton flavor violating decays
Z-->li lj
|
References added, final version to appear in Physical Review D
|
Phys.Rev. D65 (2002) 073010
|
10.1103/PhysRevD.65.073010
| null |
hep-ph
| null |
A comprehensive analysis of the lepton flavor violating (LFV) decays Z-->li
lj is presented within the effective Lagrangian approach. Both the decoupling
and nondecoupling scenarios are explored. The experimental constraints from li
--> lj lk \bar{lk} and li -->lj gamma as well as some relationships arising
from the gauge invariance of the effective Lagrangian are used to put
constraints on Z-->li lj. It is found that while current experimental data
impose very strong constraints on Z-->mu e, the channel Z --> tau mu (e)still
may be at the reach of the planned TESLA collider.
|
[
{
"created": "Tue, 4 Dec 2001 23:10:45 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Jan 2002 22:24:16 GMT",
"version": "v2"
}
] |
2009-11-07
|
[
[
"Flores-Tlalpa",
"A.",
""
],
[
"Hernandez",
"J. M.",
""
],
[
"Tavares-Velasco",
"G.",
""
],
[
"Toscano",
"J. J.",
""
]
] |
A comprehensive analysis of the lepton flavor violating (LFV) decays Z-->li lj is presented within the effective Lagrangian approach. Both the decoupling and nondecoupling scenarios are explored. The experimental constraints from li --> lj lk \bar{lk} and li -->lj gamma as well as some relationships arising from the gauge invariance of the effective Lagrangian are used to put constraints on Z-->li lj. It is found that while current experimental data impose very strong constraints on Z-->mu e, the channel Z --> tau mu (e)still may be at the reach of the planned TESLA collider.
|
2403.13966
|
Szymon Zi\k{e}ba
|
Biswajit Karmakar, Szymon Zi\k{e}ba
|
Constraining Neutrino Mixing Schemes with Correlations of Oscillation
Data
|
6 pages, 3 figures, submitted to Proceedings of "XXX Cracow EPIPHANY
Conference on Precision Physics at High Energy Colliders"
| null | null | null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
Correlations obtained from neutrino oscillation data on mixing parameters may
help to validate neutrino mixing schemes. In this context, we explore how
correlations of neutrino oscillation parameters affect the $\rm{TM}_1$ and
$\rm{TM}_2$ mixing scenarios.
|
[
{
"created": "Wed, 20 Mar 2024 20:41:30 GMT",
"version": "v1"
}
] |
2024-03-22
|
[
[
"Karmakar",
"Biswajit",
""
],
[
"Zięba",
"Szymon",
""
]
] |
Correlations obtained from neutrino oscillation data on mixing parameters may help to validate neutrino mixing schemes. In this context, we explore how correlations of neutrino oscillation parameters affect the $\rm{TM}_1$ and $\rm{TM}_2$ mixing scenarios.
|
0707.0817
|
Wei-shui Xu
|
Yi-hong Gao, Wei-shui Xu and Ding-fang Zeng
|
Viscosity and jet quenching from holographic model
|
5 pages, minor changes and references added
| null | null | null |
hep-ph
| null |
We consider the backreaction of the fundamental flavor degrees of freedom on
the AdS$_5$-Schwarz background, and calculate their contributions to the shear
viscosity and jet-quenching parameter of the thermal quark-gluon plasma.
|
[
{
"created": "Thu, 5 Jul 2007 16:01:13 GMT",
"version": "v1"
},
{
"created": "Sun, 23 Sep 2007 14:57:23 GMT",
"version": "v2"
}
] |
2007-09-23
|
[
[
"Gao",
"Yi-hong",
""
],
[
"Xu",
"Wei-shui",
""
],
[
"Zeng",
"Ding-fang",
""
]
] |
We consider the backreaction of the fundamental flavor degrees of freedom on the AdS$_5$-Schwarz background, and calculate their contributions to the shear viscosity and jet-quenching parameter of the thermal quark-gluon plasma.
|
hep-ph/9805328
|
Michael A. Doncheski
|
M. A. Doncheski and R. W. Robinett
|
Radiation zeros and scalar particles beyond the standard model
|
18 pages (LaTeX) plus 5 postscript figures
|
Phys.Lett. B435 (1998) 364-372
|
10.1016/S0370-2693(98)00807-7
|
PSU/TH/199
|
hep-ph
| null |
Standard radiation zeros arise from the factorization properties of
tree-level amplitudes involving a massless photon and can occur when all
charged particles in the initial and final state have the same sign. We
investigate how several different processes involving new scalar particles
beyond the standard model may exhibit radiation zeros and how this structure
might be exploited to probe their electromagnetic structure. We focus on (i)
unnoticed aspects of angular zeros in the process e- + e- --> Delta-- + gamma
for doubly charged Higgs boson (or any bilepton) production and (ii) the
process gamma + e- --> q + S/V for scalar (S) or vector (V) leptoquarks (LQs).
We also discuss how factorized amplitudes and radiation zeros may appear in the
gauge boson fusion production of non-conjugate leptoquark pairs via gamma + W
--> S_i + S_j* in high energy ee reactions and how the zeros affect the
production cross-sections for various types of scalar leptoquarks.
|
[
{
"created": "Thu, 14 May 1998 17:12:30 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Doncheski",
"M. A.",
""
],
[
"Robinett",
"R. W.",
""
]
] |
Standard radiation zeros arise from the factorization properties of tree-level amplitudes involving a massless photon and can occur when all charged particles in the initial and final state have the same sign. We investigate how several different processes involving new scalar particles beyond the standard model may exhibit radiation zeros and how this structure might be exploited to probe their electromagnetic structure. We focus on (i) unnoticed aspects of angular zeros in the process e- + e- --> Delta-- + gamma for doubly charged Higgs boson (or any bilepton) production and (ii) the process gamma + e- --> q + S/V for scalar (S) or vector (V) leptoquarks (LQs). We also discuss how factorized amplitudes and radiation zeros may appear in the gauge boson fusion production of non-conjugate leptoquark pairs via gamma + W --> S_i + S_j* in high energy ee reactions and how the zeros affect the production cross-sections for various types of scalar leptoquarks.
|
2205.07474
|
Josef Pradler
|
Josef Pradler
|
Is there a radio excess from the decoupling of pre-recombination
bremsstrahlung?
|
3 pages
|
Res. Notes AAS 6 266 (2022)
|
10.3847/2515-5172/acab64
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Recently it has been suggested that thermal bremsstrahlung emission, when it
decouples prior to recombination, creates an excess over the Planck cosmic
microwave background spectrum at sub-GHz frequencies. Remarkable by itself,
this would also explain a long-standing unexplained deficit in the predictions
of the extragalactic radio background. In this brief note we reiterate that no
such non-thermal component can arise by itself when matter and radiation remain
kinetically coupled.
|
[
{
"created": "Mon, 16 May 2022 06:57:52 GMT",
"version": "v1"
}
] |
2022-12-19
|
[
[
"Pradler",
"Josef",
""
]
] |
Recently it has been suggested that thermal bremsstrahlung emission, when it decouples prior to recombination, creates an excess over the Planck cosmic microwave background spectrum at sub-GHz frequencies. Remarkable by itself, this would also explain a long-standing unexplained deficit in the predictions of the extragalactic radio background. In this brief note we reiterate that no such non-thermal component can arise by itself when matter and radiation remain kinetically coupled.
|
hep-ph/9402285
|
Mabq
|
Tao Huang, Bo-Qiang Ma and Qi-Xing Shen
|
Analysis of the Pion Wave Function in Light-Cone Formalism
|
22 Latex pages
|
Phys.Rev. D49 (1994) 1490-1499
|
10.1103/PhysRevD.49.1490
| null |
hep-ph
| null |
Several general constraints are suggested to analyze the pionic valence-state
wave function. It is found that the present model wave functions used in
light-cone formalism of perturbative quantum chromodynamics have failed these
requirements to fit the pionic form factor data and the reasonable
valence-state structure function which does not exceed the pionic structure
function data for $x \rightarrow 1$ simultaneously. Furthermore, it is pointed
out that there is a possibility to find model wave functions which can satisfy
all of general constraints. Also we show that there are two higher helicity
$(\lambda_{1} + \lambda_{2} =\pm1)$ components in the light-cone wave function
for the pion as a natural consequence from the Melosh rotation and it is
speculated that these components should be incorporated into the perturbative
quantum chromodynamics.
|
[
{
"created": "Tue, 15 Feb 1994 16:31:53 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Huang",
"Tao",
""
],
[
"Ma",
"Bo-Qiang",
""
],
[
"Shen",
"Qi-Xing",
""
]
] |
Several general constraints are suggested to analyze the pionic valence-state wave function. It is found that the present model wave functions used in light-cone formalism of perturbative quantum chromodynamics have failed these requirements to fit the pionic form factor data and the reasonable valence-state structure function which does not exceed the pionic structure function data for $x \rightarrow 1$ simultaneously. Furthermore, it is pointed out that there is a possibility to find model wave functions which can satisfy all of general constraints. Also we show that there are two higher helicity $(\lambda_{1} + \lambda_{2} =\pm1)$ components in the light-cone wave function for the pion as a natural consequence from the Melosh rotation and it is speculated that these components should be incorporated into the perturbative quantum chromodynamics.
|
hep-ph/9711457
|
Mary Hall Reno
|
L. Pasquali (U Iowa), M. H. Reno (U Iowa and CERN), I. Sarcevic (U
Arizona)
|
Muon and Muon Neutrino Fluxes from Atmospheric Charm
|
3 pages, submitted to the Proceedings of the Fifth International
Workshop on Topics in Astroparticle and Underground Physics, Sept. 1997
|
Nucl.Phys.Proc.Suppl. 70 (1999) 361-363
|
10.1016/S0920-5632(98)00452-6
| null |
hep-ph astro-ph
| null |
The charm contribution to the atmospheric fluxes of muons and muon neutrinos
may be enhanced by as much as a factor of 10 when one includes the
contributions of D->pi,K->leptons and folds in uncertainties in the charm cross
section and energy distribution. In the energy range considered here, from 100
GeV to 10 TeV, the charm contribution is small compared to the conventional
flux of muons and muon neutrinos.
|
[
{
"created": "Tue, 25 Nov 1997 08:18:24 GMT",
"version": "v1"
}
] |
2015-06-25
|
[
[
"Pasquali",
"L.",
"",
"U Iowa"
],
[
"Reno",
"M. H.",
"",
"U Iowa and CERN"
],
[
"Sarcevic",
"I.",
"",
"U\n Arizona"
]
] |
The charm contribution to the atmospheric fluxes of muons and muon neutrinos may be enhanced by as much as a factor of 10 when one includes the contributions of D->pi,K->leptons and folds in uncertainties in the charm cross section and energy distribution. In the energy range considered here, from 100 GeV to 10 TeV, the charm contribution is small compared to the conventional flux of muons and muon neutrinos.
|
1610.04765
|
Francesco Giovanni Celiberto
|
F. Caporale, F.G. Celiberto, G. Chachamis, D. Gordo Gomez, B. Murdaca,
A. Sabio Vera
|
High energy effects in multi-jet production at LHC
|
7 pages, 2 figures, presented by F.G. Celiberto at the 24th Low-x
Meeting, 6-11 June 2016, K\'aroly R\'obert F\H{o}iskola, Gy\"ong\"yos,
Hungary
|
Journal of Central European Green Innovation 5 (2017) no.2, 47
| null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study differential cross sections for the production of three and four
jets in multi-Regge kinematics, the main interest lying on azimuthal angle
dependences. The theoretical setup is the jet production from a single BFKL
ladder with a convolution of two/three BFKL Green functions, where two
forward/backward jets are always tagged in the final state. Furthermore, we
require the tagging of one/two further jets in more central regions of the
detectors with a relative separation in rapidity. We found, as result, that the
dependence on transverse momenta and rapidities of the central jets can be
considered as a distinct signal of the onset of BFKL dynamics.
|
[
{
"created": "Sat, 15 Oct 2016 17:11:45 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Sep 2017 22:52:15 GMT",
"version": "v2"
}
] |
2017-09-12
|
[
[
"Caporale",
"F.",
""
],
[
"Celiberto",
"F. G.",
""
],
[
"Chachamis",
"G.",
""
],
[
"Gomez",
"D. Gordo",
""
],
[
"Murdaca",
"B.",
""
],
[
"Vera",
"A. Sabio",
""
]
] |
We study differential cross sections for the production of three and four jets in multi-Regge kinematics, the main interest lying on azimuthal angle dependences. The theoretical setup is the jet production from a single BFKL ladder with a convolution of two/three BFKL Green functions, where two forward/backward jets are always tagged in the final state. Furthermore, we require the tagging of one/two further jets in more central regions of the detectors with a relative separation in rapidity. We found, as result, that the dependence on transverse momenta and rapidities of the central jets can be considered as a distinct signal of the onset of BFKL dynamics.
|
hep-ph/0312268
|
Timothy L. Barklow
|
Timothy L. Barklow
|
Higgs Coupling Measurements at a 1 TeV Linear Collider
|
Correct typo in Table 2
| null | null |
SLAC-PUB-10283
|
hep-ph
| null |
Methods for extracting Higgs boson signals at a 1 TeV center-of-mass energy
e+e- linear collider are described. In addition, estimates are given for the
accuracy with which branching fractions can be measured for Higgs boson decays
to bb, WW, gluon-gluon, and gamma-gamma.
|
[
{
"created": "Thu, 18 Dec 2003 21:19:44 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Jan 2004 19:51:57 GMT",
"version": "v2"
}
] |
2007-05-23
|
[
[
"Barklow",
"Timothy L.",
""
]
] |
Methods for extracting Higgs boson signals at a 1 TeV center-of-mass energy e+e- linear collider are described. In addition, estimates are given for the accuracy with which branching fractions can be measured for Higgs boson decays to bb, WW, gluon-gluon, and gamma-gamma.
|
0707.2395
|
Alexander Ilyichev
|
A. Ilyichev, S. Lukashevich, N. Maksimenko
|
Moving medium electrodynamics approach for description of the electric
and magnetic static polarizable properties of the nucleon at low energy
|
11 pages, 3 figures
| null | null | null |
hep-ph
| null |
Using the relativistic electrodynamics of continuous media formalism and main
relativistic quantum field theory principles the covariant Lagrangian of
electromagnetic field interaction with polarizable 1/2-spin particles have been
obtained. This Lagrangian let us to determine canonical and metric
energy-momentum tensors as well as low-energy Compton scattering amplitude. The
application of this Lagrangian for the calculation of the radiative correction
to the imaginary part of double virtual Compton scattering is demonstrated.
|
[
{
"created": "Tue, 17 Jul 2007 05:52:40 GMT",
"version": "v1"
}
] |
2007-07-18
|
[
[
"Ilyichev",
"A.",
""
],
[
"Lukashevich",
"S.",
""
],
[
"Maksimenko",
"N.",
""
]
] |
Using the relativistic electrodynamics of continuous media formalism and main relativistic quantum field theory principles the covariant Lagrangian of electromagnetic field interaction with polarizable 1/2-spin particles have been obtained. This Lagrangian let us to determine canonical and metric energy-momentum tensors as well as low-energy Compton scattering amplitude. The application of this Lagrangian for the calculation of the radiative correction to the imaginary part of double virtual Compton scattering is demonstrated.
|
hep-ph/0305149
|
Konstantin Klimenko
|
D. Ebert, K.G. Klimenko
|
Quark droplets stability induced by external magnetic field
|
16 pages, 9 figures, REVTEX4; new references added; minor changes of
the text
|
Nucl.Phys. A728 (2003) 203-225
|
10.1016/j.nuclphysa.2003.08.021
| null |
hep-ph
| null |
The influence of a constant homogeneous external magnetic field $H$ on the
formation and stability of quark droplets is investigated within a simple Nambu
-- Jona-Lasinio model by using a thermodynamic approach. For a vanishing
magnetic field stable quark droplets, which are schematically the bags of
massless quarks, are allowed to exist only at $G>G_{bag}$, where $G$ is the
quark coupling constant, $G_{bag}=1.37G_{crit}$, and $G_{crit}$ is the value of
the coupling constant above which chiral symmetry is spontaneously broken down.
On the other hand, a nonvanishing external magnetic field can induce the
stability of quark droplets so that they may exist even at $G<G_{bag}$. In this
case, depending on the value of $H$, quark droplets are composed either of
massive or massless quarks.
|
[
{
"created": "Wed, 14 May 2003 09:27:32 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Jun 2003 13:39:46 GMT",
"version": "v2"
}
] |
2015-06-25
|
[
[
"Ebert",
"D.",
""
],
[
"Klimenko",
"K. G.",
""
]
] |
The influence of a constant homogeneous external magnetic field $H$ on the formation and stability of quark droplets is investigated within a simple Nambu -- Jona-Lasinio model by using a thermodynamic approach. For a vanishing magnetic field stable quark droplets, which are schematically the bags of massless quarks, are allowed to exist only at $G>G_{bag}$, where $G$ is the quark coupling constant, $G_{bag}=1.37G_{crit}$, and $G_{crit}$ is the value of the coupling constant above which chiral symmetry is spontaneously broken down. On the other hand, a nonvanishing external magnetic field can induce the stability of quark droplets so that they may exist even at $G<G_{bag}$. In this case, depending on the value of $H$, quark droplets are composed either of massive or massless quarks.
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.