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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2201.03951 | Kanat Nurlan | M.K. Volkov, A.A. Pivovarov, K. Nurlan | Low-energy interactions of mesons with participation of the first
radially excited states in $U(3) \times U(3)$ NJL model | 62 pages, 32 figures and 8 tables | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $U(3) \times U(3)$ chiral symmetric NJL model describing pseudoscalar,
vector, and axial vector mesons in both the ground state and first radially
excited states is shortly presented in this review. In this model, it is
possible to describe a large number of low-energy interactions of mesons,
$\tau$ lepton decays into mesons and processes of meson production in
electron-positron annihilations in satisfactory agreement with the experiments.
In describing a number of processes, it turned out to be necessary to take into
account the interactions of mesons in the final state.
| [
{
"created": "Tue, 11 Jan 2022 13:56:37 GMT",
"version": "v1"
}
] | 2022-01-12 | [
[
"Volkov",
"M. K.",
""
],
[
"Pivovarov",
"A. A.",
""
],
[
"Nurlan",
"K.",
""
]
] | The $U(3) \times U(3)$ chiral symmetric NJL model describing pseudoscalar, vector, and axial vector mesons in both the ground state and first radially excited states is shortly presented in this review. In this model, it is possible to describe a large number of low-energy interactions of mesons, $\tau$ lepton decays into mesons and processes of meson production in electron-positron annihilations in satisfactory agreement with the experiments. In describing a number of processes, it turned out to be necessary to take into account the interactions of mesons in the final state. |
0801.2176 | Marcelo Loewe | Marcelo Loewe and Cristian Mart\'inez V | Thermal Corrections to $\pi$-$\pi$ Scattering Lengths in the Linear
Sigma Model | 8 pages. Keywords: Finite temperature field theory; scattering
lengths; linear sigma model. A new reference has been added. Written in
RevTex4. The paper is being accepted for publication in Phys. Rev. D. The
size of the manuscript was reduced considerably | Phys.Rev.D77:105006,2008; Erratum-ibid.D78:069902,2008 | 10.1103/PhysRevD.77.105006 10.1103/PhysRevD.78.069902 | null | hep-ph | null | In this article we explore the thermal evolution of the $\pi$-$\pi$
scattering lengths in the frame of the linear sigma model. We compute, using
thermofield dynamics, all the one loop diagrams that contribute to $\pi$-$\pi$
scattering. We restrict ourselves to temperature correction only in the pion
sector, due to the Boltzmann supression for the sigma meson. From this analysis
we obtain the thermal behavior of $a_0^0$ and $a_0^2$, s-waves scattering
lengths in the isospin channel I=0 and I=2 respectively. It turns out that
$a_0^0$ grows whereas $a_0^2$ diminishes as function of temperature. We compare
our results with other determinations of the thermal behavior of these
magnitudes.
| [
{
"created": "Mon, 14 Jan 2008 22:38:44 GMT",
"version": "v1"
},
{
"created": "Fri, 18 Jan 2008 00:56:18 GMT",
"version": "v2"
},
{
"created": "Wed, 23 Jan 2008 21:57:46 GMT",
"version": "v3"
},
{
"created": "Thu, 27 Mar 2008 20:38:44 GMT",
"version": "v4"
}
] | 2014-11-18 | [
[
"Loewe",
"Marcelo",
""
],
[
"Martínez",
"Cristian",
"V"
]
] | In this article we explore the thermal evolution of the $\pi$-$\pi$ scattering lengths in the frame of the linear sigma model. We compute, using thermofield dynamics, all the one loop diagrams that contribute to $\pi$-$\pi$ scattering. We restrict ourselves to temperature correction only in the pion sector, due to the Boltzmann supression for the sigma meson. From this analysis we obtain the thermal behavior of $a_0^0$ and $a_0^2$, s-waves scattering lengths in the isospin channel I=0 and I=2 respectively. It turns out that $a_0^0$ grows whereas $a_0^2$ diminishes as function of temperature. We compare our results with other determinations of the thermal behavior of these magnitudes. |
1712.05803 | Kiel Howe | Prateek Agrawal, Kiel Howe | A Flavorful Factoring of the Strong CP Problem | 15 pages, 6 figures | null | 10.1007/JHEP12(2018)035 | FERMILAB-PUB-17-562-PPD | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the intimate connection between the strong CP problem and the
flavor structure of the Standard Model, we present a flavor model that revives
and extends the classic ${m_u=0}$ solution to the strong CP problem. QCD is
embedded into a $SU(3)_1\times SU(3)_2 \times SU(3)_3$ gauge group, with each
generation of quarks charged under the respective $SU(3)$. The non-zero value
of the up-quark Yukawa coupling (along with the strange quark and bottom-quark
Yukawas) is generated by contributions from small instantons at a new scale $M
\gg \Lambda_{QCD}$. The Higgsing of $SU(3)^3\to SU(3)_c$ allows dimension-5
operators that generate the Standard Model flavor structure and can be
completed in a simple renormalizable theory. The smallness of the third
generation mixing angles can naturally emerge in this picture, and is connected
to the smallness of threshold corrections to $\bar\theta$. Remarkably,
$\bar\theta$ is essentially fixed by the measured quark masses and mixings, and
is estimated to be close to the current experimental bound and well within
reach of the next generation of neutron and proton EDM experiments.
| [
{
"created": "Fri, 15 Dec 2017 19:00:03 GMT",
"version": "v1"
}
] | 2018-12-26 | [
[
"Agrawal",
"Prateek",
""
],
[
"Howe",
"Kiel",
""
]
] | Motivated by the intimate connection between the strong CP problem and the flavor structure of the Standard Model, we present a flavor model that revives and extends the classic ${m_u=0}$ solution to the strong CP problem. QCD is embedded into a $SU(3)_1\times SU(3)_2 \times SU(3)_3$ gauge group, with each generation of quarks charged under the respective $SU(3)$. The non-zero value of the up-quark Yukawa coupling (along with the strange quark and bottom-quark Yukawas) is generated by contributions from small instantons at a new scale $M \gg \Lambda_{QCD}$. The Higgsing of $SU(3)^3\to SU(3)_c$ allows dimension-5 operators that generate the Standard Model flavor structure and can be completed in a simple renormalizable theory. The smallness of the third generation mixing angles can naturally emerge in this picture, and is connected to the smallness of threshold corrections to $\bar\theta$. Remarkably, $\bar\theta$ is essentially fixed by the measured quark masses and mixings, and is estimated to be close to the current experimental bound and well within reach of the next generation of neutron and proton EDM experiments. |
2402.16385 | Boris Ermolaev | B.I. Ermolaev | Solution to the Proton Spin Puzzle | 9 pages, 3 figures | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We show that description of the quark and gluon helicities in the
Double-Logarithmic Approximation (DLA) solves the proton spin puzzle. First we
explain how to solve this problem in the straightforward way by combining the
RHIC data and expressions for the helicities calculated in DLA. These
expressions are complicated to use, so we approximate the helicities by simpler
DL expressions and obtain a tentative solution to the puzzle.
| [
{
"created": "Mon, 26 Feb 2024 08:18:04 GMT",
"version": "v1"
}
] | 2024-02-27 | [
[
"Ermolaev",
"B. I.",
""
]
] | We show that description of the quark and gluon helicities in the Double-Logarithmic Approximation (DLA) solves the proton spin puzzle. First we explain how to solve this problem in the straightforward way by combining the RHIC data and expressions for the helicities calculated in DLA. These expressions are complicated to use, so we approximate the helicities by simpler DL expressions and obtain a tentative solution to the puzzle. |
hep-ph/0308171 | Hyun-Chul Kim | Hyun-Ah Choi and Hyun-Chul Kim | Effective chiral lagrangian in the chiral limit from the instanton
vacuum | 14 pages, 5 figures, submitted to Phys.Rev. D | Phys.Rev. D69 (2004) 054004 | 10.1103/PhysRevD.69.054004 | PNU-NTG-03/2003 | hep-ph | null | We study the effective chiral Lagrangian in the chiral limit from the
instanton vacuum. Starting from the nonlocal effective chiral action, we derive
the effective chiral Lagrangian, using the derivative expansion to order
$O(p^4)$ in the chiral limit. The low energy constants, $L_1$, $L_2$, and $L_3$
are determined and compared with various models and the corresponding empirical
data. The results are in a good agreement with the data. We also discuss about
the upper limit of the sigma meson, based on the present results.
| [
{
"created": "Sun, 17 Aug 2003 21:42:18 GMT",
"version": "v1"
}
] | 2016-09-06 | [
[
"Choi",
"Hyun-Ah",
""
],
[
"Kim",
"Hyun-Chul",
""
]
] | We study the effective chiral Lagrangian in the chiral limit from the instanton vacuum. Starting from the nonlocal effective chiral action, we derive the effective chiral Lagrangian, using the derivative expansion to order $O(p^4)$ in the chiral limit. The low energy constants, $L_1$, $L_2$, and $L_3$ are determined and compared with various models and the corresponding empirical data. The results are in a good agreement with the data. We also discuss about the upper limit of the sigma meson, based on the present results. |
1205.6931 | Wilco J. den Dunnen | Wilco J. den Dunnen, Daniel Boer, Cristian Pisano, Marc Schlegel and
Werner Vogelsang | Linearly polarized Gluons and the Higgs Transverse Momentum Distribution | DIS2012 conference proceedings contribution. Corrected typos in Eq.
(7) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the possible role of linearly polarized gluons in Higgs
production from unpolarized pp collisions. The transverse momentum distribution
of the produced Higgs boson is found to exhibit a modulation with respect to
the naive, unpolarized expectation, with the sign depending on the parity of
the Higgs boson. The transverse momentum distribution of a scalar Higgs will,
therefore, have a shape clearly different from a pseudoscalar Higgs. We suggest
that this effect can be used to determine the parity of the Higgs at the LHC,
without the need to use challenging angular distributions.
| [
{
"created": "Thu, 31 May 2012 09:32:24 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Jun 2012 14:01:47 GMT",
"version": "v2"
}
] | 2012-06-11 | [
[
"Dunnen",
"Wilco J. den",
""
],
[
"Boer",
"Daniel",
""
],
[
"Pisano",
"Cristian",
""
],
[
"Schlegel",
"Marc",
""
],
[
"Vogelsang",
"Werner",
""
]
] | We investigate the possible role of linearly polarized gluons in Higgs production from unpolarized pp collisions. The transverse momentum distribution of the produced Higgs boson is found to exhibit a modulation with respect to the naive, unpolarized expectation, with the sign depending on the parity of the Higgs boson. The transverse momentum distribution of a scalar Higgs will, therefore, have a shape clearly different from a pseudoscalar Higgs. We suggest that this effect can be used to determine the parity of the Higgs at the LHC, without the need to use challenging angular distributions. |
0903.3595 | Gabriel Denicol | G. S. Denicol, T. Kodama, T. Koide and Ph. Mota | Effect of bulk viscosity on Elliptic Flow near QCD phase transition | 14 pages, 12 figures | Phys.Rev.C80:064901,2009 | 10.1103/PhysRevC.80.064901 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Effects of the bulk viscosity on the elliptic flow are studied. To introduce
a realistic equation of state and transport coefficients, we apply the results
of the lattice QCD and hadron resonance gas calculations for these quantities.
We found that the bulk viscosity acts in a non trivial manner on the elliptic
flow $v_{2}$. The reduction of $v_{2}$ is more effective at low $p_{T}$
compared to the case of shear viscosity, whereas at high $p_{T}$, the situation
is reversed, leading to $v_{2}$ enhancement. We argue that this is caused by
the competition of the critical behaviors of the equation of state and the
transport coefficients. We further found that Grad's method with the 14 moments
approximation is not applicable to estimate the viscous effects for the
one-particle distribution function at the freeze out.
| [
{
"created": "Fri, 20 Mar 2009 19:29:36 GMT",
"version": "v1"
},
{
"created": "Sat, 10 Oct 2009 01:04:03 GMT",
"version": "v2"
}
] | 2009-12-14 | [
[
"Denicol",
"G. S.",
""
],
[
"Kodama",
"T.",
""
],
[
"Koide",
"T.",
""
],
[
"Mota",
"Ph.",
""
]
] | Effects of the bulk viscosity on the elliptic flow are studied. To introduce a realistic equation of state and transport coefficients, we apply the results of the lattice QCD and hadron resonance gas calculations for these quantities. We found that the bulk viscosity acts in a non trivial manner on the elliptic flow $v_{2}$. The reduction of $v_{2}$ is more effective at low $p_{T}$ compared to the case of shear viscosity, whereas at high $p_{T}$, the situation is reversed, leading to $v_{2}$ enhancement. We argue that this is caused by the competition of the critical behaviors of the equation of state and the transport coefficients. We further found that Grad's method with the 14 moments approximation is not applicable to estimate the viscous effects for the one-particle distribution function at the freeze out. |
2011.04941 | Mahmoud Nassar | Mahmoud Hanafy (Physics Department, Benha University, Benha, Egypt)
and Muhammad Maher (Helwan University, Physics Department, Ain Helwan, Egypt) | An approach of statistical corrections to interactions in hadron
resonance gas | 13 pages, 3 figures | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new model for hadrons with quantum mechanical attractive and
repulsive interactions sensitive to some spatial correlation length parameter
inspired by Beth-Uhlenbeck quantum mechanical non-ideal gas model
\cite{uhlenbeck1937quantum}. We confront the thermodynamics calculated using
our model with a corresponding recent lattice data at four different values of
the baryon chemical potential, $\mu_{\mathtt{b}}= 0, 170, 340, 425~$MeV over
temperatures ranging from $130$ MeV to $200~$MeV and for five values for the
correlation length ranging from $0$ to $0.2~$fm. For equilibrium temperatures
up to the vicinity of the chiral phase transition temperature $\simeq 160~$MeV,
a decent fitting between the model and the lattice data is observed for
different values of $r$, especially at $(\mu_{\mathtt{b}}, r) = (170,0.05),
(340,0.1)$, and $(340,0.15)$, where $\mu_{\mathtt{b}}$ is in MeV and $r$ is in
fm. For vanishing chemical potential, the uncorrelated model ($r=0$), which
corresponds to ideal hadron resonance gas model seems to offer the best fit.
The quantum hadron correlations seem to be more probable at non-vanishing
chemical potentials, especially within the range $\mu_{\mathtt{b}}\in [170,
340~$MeV$]$.
| [
{
"created": "Tue, 10 Nov 2020 07:01:40 GMT",
"version": "v1"
}
] | 2020-11-11 | [
[
"Hanafy",
"Mahmoud",
"",
"Physics Department, Benha University, Benha, Egypt"
],
[
"Maher",
"Muhammad",
"",
"Helwan University, Physics Department, Ain Helwan, Egypt"
]
] | We propose a new model for hadrons with quantum mechanical attractive and repulsive interactions sensitive to some spatial correlation length parameter inspired by Beth-Uhlenbeck quantum mechanical non-ideal gas model \cite{uhlenbeck1937quantum}. We confront the thermodynamics calculated using our model with a corresponding recent lattice data at four different values of the baryon chemical potential, $\mu_{\mathtt{b}}= 0, 170, 340, 425~$MeV over temperatures ranging from $130$ MeV to $200~$MeV and for five values for the correlation length ranging from $0$ to $0.2~$fm. For equilibrium temperatures up to the vicinity of the chiral phase transition temperature $\simeq 160~$MeV, a decent fitting between the model and the lattice data is observed for different values of $r$, especially at $(\mu_{\mathtt{b}}, r) = (170,0.05), (340,0.1)$, and $(340,0.15)$, where $\mu_{\mathtt{b}}$ is in MeV and $r$ is in fm. For vanishing chemical potential, the uncorrelated model ($r=0$), which corresponds to ideal hadron resonance gas model seems to offer the best fit. The quantum hadron correlations seem to be more probable at non-vanishing chemical potentials, especially within the range $\mu_{\mathtt{b}}\in [170, 340~$MeV$]$. |
2010.14412 | Wojciech Wislicki | Wojciech Wislicki | Bounds on Plack-scale deformation of CPT from lifetimes and interference | 6 pages, 4 figs, Proceedings of EPS-HEP2019 | null | 10.5506/APhysPolB.51.135 | P0S(EPS-HEP2029)059 | hep-ph gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Deformed relativistic kinematics, expected to emerge in a flat-spacetime
limit of quantum gravity, predicts violation of discrete symmetries at energy
scale in the vicinity of the Planck mass. Momentum-dependent deformations of
the C, P and T invariance are derived from the \k{appa}-deformed Poincar\'e
algebra. Deformation of the CPT symmetry leads to a subtle violation of Lorentz
symmetry. This entails some small but measurable phenomenological consequences,
as corrections to characteristics of time evolution: particle lifetimes or
frequency of flavour oscillations in two-particle states at high energy. We
argue here that using current experimental precisions on the muon lifetime one
can bound the deformation parameter \k{appa} > 10^14 GeV at LHC energy and move
this limit even to 10^16 GeV at Future Circular Collider, planned at CERN.
Weaker limits on deformation can be also obtained from interference of neutral
mesons. In case of B0s from {\Upsilon} decay it amounts to \k{appa} > 10^8 GeV
at confidence level 99%.
| [
{
"created": "Tue, 27 Oct 2020 16:21:34 GMT",
"version": "v1"
}
] | 2020-11-04 | [
[
"Wislicki",
"Wojciech",
""
]
] | Deformed relativistic kinematics, expected to emerge in a flat-spacetime limit of quantum gravity, predicts violation of discrete symmetries at energy scale in the vicinity of the Planck mass. Momentum-dependent deformations of the C, P and T invariance are derived from the \k{appa}-deformed Poincar\'e algebra. Deformation of the CPT symmetry leads to a subtle violation of Lorentz symmetry. This entails some small but measurable phenomenological consequences, as corrections to characteristics of time evolution: particle lifetimes or frequency of flavour oscillations in two-particle states at high energy. We argue here that using current experimental precisions on the muon lifetime one can bound the deformation parameter \k{appa} > 10^14 GeV at LHC energy and move this limit even to 10^16 GeV at Future Circular Collider, planned at CERN. Weaker limits on deformation can be also obtained from interference of neutral mesons. In case of B0s from {\Upsilon} decay it amounts to \k{appa} > 10^8 GeV at confidence level 99%. |
1112.3549 | Vladimir Kopeliovich Benedikt | Vladimir Kopeliovich (Moscow, INR), Irina Potashnikova (Santa Maria
U., Valparaiso) | Restriction on the Neutron-Antineutron Oscillations from the SNO Data on
the Deuteron Stability | 8 pages, 1 fig.; presented at the 3-d International Workshop on
Baryon and Lepton number Violation (BLV-2011), Gatlinburg, Tennessee, USA,
Sept. 22-24 2011 and Session of the Nuclear Physics Department of RAS, ITEP,
Moscow, Nov. 21-25 2011; submitted to JETP Lett. [Pisma Zh.Eksp.Teor.Fiz] | JETP Lett.95:1-5,2012; Pisma Zh.Eksp.Teor.Fiz.95:3-7,2012 | 10.1134/S0021364012010079 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Restriction on the neutron-antineutron oscillation time in vacuum is obtained
from latest SNO data on the deuteron stability, $\tau_D\,>\,3.01^.10^{31}$
years. Calculation performed within the quantum field theory based diagram
technique reproduces satisfactorily results of the potential approach
previously developed. The dependence of the obtained restriction on the total
spin of the annihilating $N\bar N$ system and the deuteron wave function
modifications is discussed.
| [
{
"created": "Thu, 15 Dec 2011 16:05:48 GMT",
"version": "v1"
}
] | 2015-06-03 | [
[
"Kopeliovich",
"Vladimir",
"",
"Moscow, INR"
],
[
"Potashnikova",
"Irina",
"",
"Santa Maria\n U., Valparaiso"
]
] | Restriction on the neutron-antineutron oscillation time in vacuum is obtained from latest SNO data on the deuteron stability, $\tau_D\,>\,3.01^.10^{31}$ years. Calculation performed within the quantum field theory based diagram technique reproduces satisfactorily results of the potential approach previously developed. The dependence of the obtained restriction on the total spin of the annihilating $N\bar N$ system and the deuteron wave function modifications is discussed. |
1109.5539 | Munshi Golam Mustafa Dr. | Raktim Abir, Carsten Greiner, Mauricio Martinez, Munshi G. Mustafa,
and Jan Uphoff | Soft gluon emission off a heavy quark revisited | A portion of the discussion and Fig. 3 changed in the text; A little
change in the abstract; Version accepted in PRD | null | 10.1103/PhysRevD.85.054012 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An improved generalized suppression factor for gluon emission off a heavy
quark is derived within perturbative QCD, which is valid for the full range of
rapidity of the radiated gluon and also has no restriction on the scaled mass
of the quark with its energy. In the appropriate limit it correctly reproduces
the usual dead cone factor in the forward rapidity region. On the other hand,
this improved suppression factor becomes close to unity in the backward
direction. This indicates a small suppression of gluon emission in the backward
region, which should have an impact on the phenomenology of heavy quark energy
loss in the hot and dense matter produced in ultra-relativistic heavy-ion
collisions.
| [
{
"created": "Mon, 26 Sep 2011 12:23:32 GMT",
"version": "v1"
},
{
"created": "Sun, 12 Feb 2012 16:17:15 GMT",
"version": "v2"
}
] | 2013-05-30 | [
[
"Abir",
"Raktim",
""
],
[
"Greiner",
"Carsten",
""
],
[
"Martinez",
"Mauricio",
""
],
[
"Mustafa",
"Munshi G.",
""
],
[
"Uphoff",
"Jan",
""
]
] | An improved generalized suppression factor for gluon emission off a heavy quark is derived within perturbative QCD, which is valid for the full range of rapidity of the radiated gluon and also has no restriction on the scaled mass of the quark with its energy. In the appropriate limit it correctly reproduces the usual dead cone factor in the forward rapidity region. On the other hand, this improved suppression factor becomes close to unity in the backward direction. This indicates a small suppression of gluon emission in the backward region, which should have an impact on the phenomenology of heavy quark energy loss in the hot and dense matter produced in ultra-relativistic heavy-ion collisions. |
1710.07165 | Adrian Lewandowski | Adrian Lewandowski (Max-Planck-Institut f\"ur Gravitationsphysik,
Potsdam) | LSZ-reduction, resonances and non-diagonal propagators: fermions and
scalars | 37 pages, 1 figure | null | 10.1016/j.nuclphysb.2018.10.020 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze in details the effects associated with mixing of fermionic fields.
In a system with an arbitrary number of Majorana or Dirac particles, a simple
proof of factorizability of residues of non-diagonal propagators at the complex
poles is given, together with a prescription for finding the "square-rooted"
residues to all orders of perturbation theory, in an arbitrary renormalization
scheme. Corresponding prescription for the scalar case is provided as well.
| [
{
"created": "Thu, 19 Oct 2017 14:48:01 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Mar 2018 12:13:25 GMT",
"version": "v2"
}
] | 2018-11-14 | [
[
"Lewandowski",
"Adrian",
"",
"Max-Planck-Institut für Gravitationsphysik,\n Potsdam"
]
] | We analyze in details the effects associated with mixing of fermionic fields. In a system with an arbitrary number of Majorana or Dirac particles, a simple proof of factorizability of residues of non-diagonal propagators at the complex poles is given, together with a prescription for finding the "square-rooted" residues to all orders of perturbation theory, in an arbitrary renormalization scheme. Corresponding prescription for the scalar case is provided as well. |
hep-ph/0412206 | Petr Zavada | Petr Zavada | Proton transversity and intrinsic motion of the quarks | Prepared for the conference SPIN2004 | null | 10.1142/9789812701909_0079 | null | hep-ph | null | The spin structure of the system of quasifree fermions having total angular
momentum $J=1/2$ is studied in a consistently covariant approach. Within this
model the relations between the spin functions are obtained. Their particular
cases are the sum rules Wanzura - Wilczek, Efremov - Leader - Teryaev,
Burkhardt - Cottingham and also the expression for the Wanzura - Wilczek twist
2 term $g_{2}^{WW}$. With the use of the proton valence quark distributions as
an input, the corresponding spin functions including transversity are obtained.
| [
{
"created": "Wed, 15 Dec 2004 08:36:21 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Zavada",
"Petr",
""
]
] | The spin structure of the system of quasifree fermions having total angular momentum $J=1/2$ is studied in a consistently covariant approach. Within this model the relations between the spin functions are obtained. Their particular cases are the sum rules Wanzura - Wilczek, Efremov - Leader - Teryaev, Burkhardt - Cottingham and also the expression for the Wanzura - Wilczek twist 2 term $g_{2}^{WW}$. With the use of the proton valence quark distributions as an input, the corresponding spin functions including transversity are obtained. |
hep-ph/0604206 | Shigehiro Yasui | S. Yasui and A. Hosaka | Quark droplets with chiral symmetry in the Nambu--Jona-Lasinio model | null | Phys.Rev. D74 (2006) 054036 | 10.1103/PhysRevD.74.054036 | null | hep-ph | null | We discuss the stability of strangelets by considering dynamical chiral
symmetry breaking. For quark droplets of finite volume, we formulate the
Nambu--Jona-Lasinio model with a basis set of the quark wave functions in the
chiral bag model. Chiral symmetry breaking for the finite volume bag is
discussed in a mean field approximation. Effects of the pion cloud including
the chiral Casimir effect are investigated. Physical quantities of the quark
droplets such as masses and radii are obtained for quark droplets of baryon
numbers up to five. We also apply our model setting to the nucleon and discuss
the stability of the quark droplets against nuclei.
| [
{
"created": "Tue, 25 Apr 2006 01:23:43 GMT",
"version": "v1"
},
{
"created": "Fri, 19 May 2006 06:02:38 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Yasui",
"S.",
""
],
[
"Hosaka",
"A.",
""
]
] | We discuss the stability of strangelets by considering dynamical chiral symmetry breaking. For quark droplets of finite volume, we formulate the Nambu--Jona-Lasinio model with a basis set of the quark wave functions in the chiral bag model. Chiral symmetry breaking for the finite volume bag is discussed in a mean field approximation. Effects of the pion cloud including the chiral Casimir effect are investigated. Physical quantities of the quark droplets such as masses and radii are obtained for quark droplets of baryon numbers up to five. We also apply our model setting to the nucleon and discuss the stability of the quark droplets against nuclei. |
2006.16626 | Sourendu Gupta | Sourendu Gupta and Rishi Sharma | Real time warm pions from the lattice using an effective theory | null | null | 10.1142/S0217751X20300215 | null | hep-ph hep-lat hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Lattice measurements provide adequate information to fix the parameters of
long distance effective field theories in Euclidean time. Using such a theory,
we examine the analytic continuation of long distance correlation functions of
composite operators at finite temperature from Euclidean to Minkowski space
time. We show through an explicit computation that the analytic continuation of
the pion correlation function is possible and gives rise to non-trivial
effects. Among them is the possibility, supported by lattice computations of
Euclidean correlators, that long distance excitations can be understood in
terms of (very massive) pions even at temperatures higher than the QCD cross
over temperature.
| [
{
"created": "Tue, 30 Jun 2020 09:40:59 GMT",
"version": "v1"
}
] | 2020-12-30 | [
[
"Gupta",
"Sourendu",
""
],
[
"Sharma",
"Rishi",
""
]
] | Lattice measurements provide adequate information to fix the parameters of long distance effective field theories in Euclidean time. Using such a theory, we examine the analytic continuation of long distance correlation functions of composite operators at finite temperature from Euclidean to Minkowski space time. We show through an explicit computation that the analytic continuation of the pion correlation function is possible and gives rise to non-trivial effects. Among them is the possibility, supported by lattice computations of Euclidean correlators, that long distance excitations can be understood in terms of (very massive) pions even at temperatures higher than the QCD cross over temperature. |
hep-ph/9305238 | null | J. Dolejsi, J. Huefner and B.Z. Kopeliovich | Colour Screening, Quark Propagation in Nuclear Matter and the Broadening
of the Momentum Distribution of Drell-Yan Pairs | LaTex file, 7 pages + 2 figs (not included, available by fax)
Heidelberg , HD-TVP-93-5 | Phys.Lett. B312 (1993) 235-239 | 10.1016/0370-2693(93)90517-L | null | hep-ph | null | We calculate the broadening of the transverse momentum distribution of a
quark propagating through nuclear matter. Colour screening plays a fundamental
role in that it cuts off quark-nucleon interactions with soft gluons. The mean
transverse momentum of the quark acquired along its trajectory, observed via
Drell-Yan pairs, is related to it the ratio of the total inelastic
meson-nucleon cross section it to the meson mean squared radius. Parameter-free
calculations agree with the data.
| [
{
"created": "Tue, 11 May 1993 08:47:08 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Dolejsi",
"J.",
""
],
[
"Huefner",
"J.",
""
],
[
"Kopeliovich",
"B. Z.",
""
]
] | We calculate the broadening of the transverse momentum distribution of a quark propagating through nuclear matter. Colour screening plays a fundamental role in that it cuts off quark-nucleon interactions with soft gluons. The mean transverse momentum of the quark acquired along its trajectory, observed via Drell-Yan pairs, is related to it the ratio of the total inelastic meson-nucleon cross section it to the meson mean squared radius. Parameter-free calculations agree with the data. |
0809.1977 | Pervez Hoodbhoy | Pervez Hoodbhoy | ADS/CFT Applied To Vector Meson Emission From A Heavy Accelerated
Nucleus | 17 pages, 1 figure | Phys.Rev.D78:115015,2008 | 10.1103/PhysRevD.78.115015 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a classical source, moving on the 4-D boundary of a 5-D ADS
space, that is coupled to quantum fields residing in the bulk.
Bremsstrahlung-like radiation of the corresponding quanta is shown to occur and
the S-matrix is derived assuming that the source is sufficiently massive so
that recoil effects are negligible. As an illustrative example, using the ADS
hard-wall model, we consider vector mesons coupled to a heavy nucleus that is
moved around at high speed in an accelerator ring. The meson radiation rate is
found to be finite but small. Much higher accelerations, such as when a pair of
heavy ions suffer an ultra peripheral collision, cause substantial emission of
various excited vector mesons. Predictions are made for the spectrum of this
radiation. A comparison is made against existing photon-pomeron fusion
calculations for the transverse momentum spectra of rho mesons. These have the
same overall shape as the recently measured transverse momentum distributions
at RHIC.
| [
{
"created": "Thu, 11 Sep 2008 12:56:58 GMT",
"version": "v1"
}
] | 2009-01-08 | [
[
"Hoodbhoy",
"Pervez",
""
]
] | We consider a classical source, moving on the 4-D boundary of a 5-D ADS space, that is coupled to quantum fields residing in the bulk. Bremsstrahlung-like radiation of the corresponding quanta is shown to occur and the S-matrix is derived assuming that the source is sufficiently massive so that recoil effects are negligible. As an illustrative example, using the ADS hard-wall model, we consider vector mesons coupled to a heavy nucleus that is moved around at high speed in an accelerator ring. The meson radiation rate is found to be finite but small. Much higher accelerations, such as when a pair of heavy ions suffer an ultra peripheral collision, cause substantial emission of various excited vector mesons. Predictions are made for the spectrum of this radiation. A comparison is made against existing photon-pomeron fusion calculations for the transverse momentum spectra of rho mesons. These have the same overall shape as the recently measured transverse momentum distributions at RHIC. |
hep-ph/0606099 | Pedro Castelo Ferreira | J. Tito Mendonca, J. Dias de Deus, P. Castelo Ferreira | Higher Harmonics in Non-Linear Vacuum from QED Effects Without Low Mass
Intermediate Particles | 4 pages, 1 figure; includes Erratum: The PVLAS signal cannot be
explained by this mechanism | Phys.Rev.Lett.97:100403,2006; Erratum-ibid.97:269901,2006 | 10.1103/PhysRevLett.97.100403 | null | hep-ph | null | We show that in the presence of a slowly rotating strong transverse magnetic
field there is an infinite spectrum of harmonic wave functions $A_n$ due to the
first order QED correction (in $\alpha^2$) given by the Euler-Heisenberg
Lagrangian. The frequency shifts are integer multiples $\pm \omega_0 n$ of the
magnetic field angular frequency rotation $\omega_0=2\pi\nu_m$ and the several
modes $n$ are coupled to the nearest harmonics $n\pm 1$. This is a new effect
due to QED vacuum fluctuations, not exploit before, that can explain, both
qualitatively and quantatively, the recent experimental results of the PVLAS
collaboration without the need of a low mass intermediate particle, hence
dismiss the recent claim of the discovery of the axion. [Erratum: The PVLAS
signal cannot be explained by this mechanism.]
| [
{
"created": "Thu, 8 Jun 2006 17:11:42 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Jul 2006 15:34:27 GMT",
"version": "v2"
},
{
"created": "Tue, 3 Jul 2007 13:14:08 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Mendonca",
"J. Tito",
""
],
[
"de Deus",
"J. Dias",
""
],
[
"Ferreira",
"P. Castelo",
""
]
] | We show that in the presence of a slowly rotating strong transverse magnetic field there is an infinite spectrum of harmonic wave functions $A_n$ due to the first order QED correction (in $\alpha^2$) given by the Euler-Heisenberg Lagrangian. The frequency shifts are integer multiples $\pm \omega_0 n$ of the magnetic field angular frequency rotation $\omega_0=2\pi\nu_m$ and the several modes $n$ are coupled to the nearest harmonics $n\pm 1$. This is a new effect due to QED vacuum fluctuations, not exploit before, that can explain, both qualitatively and quantatively, the recent experimental results of the PVLAS collaboration without the need of a low mass intermediate particle, hence dismiss the recent claim of the discovery of the axion. [Erratum: The PVLAS signal cannot be explained by this mechanism.] |
1210.8095 | Alexander Goritschnig T. | A.T. Goritschnig, B. Pire and W. Schweiger | Double handbag description of proton-antiproton annihilation into a
heavy meson pair | 25 pages | null | 10.1103/PhysRevD.87.014017 | CPHT-RR033.0612 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose to describe the process $ p \bar{p} \,\to\, \bar{D^0} D^0$ in a
perturbative QCD motivated framework where a double-handbag hard process $ u d
\bar u \bar d \to \bar{c} c$ factorizes from transition distribution
amplitudes, which are quasi forward hadronic matrix elements of $\Psi_q \Psi_q
\Psi_c $ operators, where q denotes light quarks and c denotes the heavy quark.
We advocate that the charm-quark mass acts as the large scale allowing this
factorization. We calculate this process in the simplified framework of the
scalar diquark model and present the expected cross sections for the PANDA
experiment at GSI-FAIR.
| [
{
"created": "Tue, 30 Oct 2012 17:42:28 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Oct 2013 17:18:27 GMT",
"version": "v2"
}
] | 2013-10-22 | [
[
"Goritschnig",
"A. T.",
""
],
[
"Pire",
"B.",
""
],
[
"Schweiger",
"W.",
""
]
] | We propose to describe the process $ p \bar{p} \,\to\, \bar{D^0} D^0$ in a perturbative QCD motivated framework where a double-handbag hard process $ u d \bar u \bar d \to \bar{c} c$ factorizes from transition distribution amplitudes, which are quasi forward hadronic matrix elements of $\Psi_q \Psi_q \Psi_c $ operators, where q denotes light quarks and c denotes the heavy quark. We advocate that the charm-quark mass acts as the large scale allowing this factorization. We calculate this process in the simplified framework of the scalar diquark model and present the expected cross sections for the PANDA experiment at GSI-FAIR. |
hep-ph/9409398 | null | John F. Donoghue | Calculation of a weak nonleptonic matrix element using ``Weinberg'' sum
rules | Talk presented at the XXVIII International Conference on High Energy
Physics, ICHEP94, Glasgow, Aug. 1994.] 5 pages, no figures, Latex, UMHEP-412 | null | null | null | hep-ph | null | There is a ``toy'' weak matrix element which can be expressed as an integral
over the vector and axial vector spectral functions, $\rho_V (s) - \rho_A (s)$.
I review our recent evaluation of these spectral functions, the study of four
``Weinberg'' sum rules and the calculation of this matrix element.
| [
{
"created": "Fri, 23 Sep 1994 15:46:53 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Donoghue",
"John F.",
""
]
] | There is a ``toy'' weak matrix element which can be expressed as an integral over the vector and axial vector spectral functions, $\rho_V (s) - \rho_A (s)$. I review our recent evaluation of these spectral functions, the study of four ``Weinberg'' sum rules and the calculation of this matrix element. |
hep-ph/9409227 | George W. S. Hou | Wei-Shu Hou and Hsuan-Cheng Huang | Singlet Charge $2/3$ Quark hiding the Top: Tevatron and LEP Implications | 10 pages + 3 Figures (not included), ReVTeX, NTUTH-94-18 | Phys.Rev. D51 (1995) 5285-5288 | 10.1103/PhysRevD.51.5285 | null | hep-ph | null | If $c$ and $t$ quarks are strongly mixed with a weak singlet charge $2/3$
quark, $BR(t\to \ell\nu + X)$ could be suppressed via the $t\to cH^0$ mode,
thereby the top quark could still hide below $M_W$, whereas the heavy quark
signal observed at the Tevatron is due to the dominantly singlet quark $Q$.
This may occur without affecting the small $m_c$ value. Demanding $m_Q \simeq
175$ GeV and $m_t \ltap M_W$, we find that $BR(t\to \ell\nu + X)$ cannot be too
suppressed. The heavy quark $Q$ decays via $W,\ H$, and $Z$ bosons. The latter
can lead to $b$-tagged $Z + 4$ jet events, while the strong $c$--$Q$ mixing is
reflected in sizable $Q\to sW$ fraction. $Z\to t\bar c$ decay occurs at tree
level and may be at the $10^{-3}$ order, leading to the signature of $Z\to
\ell\nu b\bar c$, all isolated and with large $p_T$, at $10^{-5}$ order.
| [
{
"created": "Mon, 5 Sep 1994 17:58:19 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Hou",
"Wei-Shu",
""
],
[
"Huang",
"Hsuan-Cheng",
""
]
] | If $c$ and $t$ quarks are strongly mixed with a weak singlet charge $2/3$ quark, $BR(t\to \ell\nu + X)$ could be suppressed via the $t\to cH^0$ mode, thereby the top quark could still hide below $M_W$, whereas the heavy quark signal observed at the Tevatron is due to the dominantly singlet quark $Q$. This may occur without affecting the small $m_c$ value. Demanding $m_Q \simeq 175$ GeV and $m_t \ltap M_W$, we find that $BR(t\to \ell\nu + X)$ cannot be too suppressed. The heavy quark $Q$ decays via $W,\ H$, and $Z$ bosons. The latter can lead to $b$-tagged $Z + 4$ jet events, while the strong $c$--$Q$ mixing is reflected in sizable $Q\to sW$ fraction. $Z\to t\bar c$ decay occurs at tree level and may be at the $10^{-3}$ order, leading to the signature of $Z\to \ell\nu b\bar c$, all isolated and with large $p_T$, at $10^{-5}$ order. |
2009.05371 | Zhi-Gang Wang | Zhi-Gang Wang | Revisit the tetraquark candidates in the $J/\psi J/\psi$ mass spectrum | 11 pages, 3 figures. arXiv admin note: text overlap with
arXiv:2006.13028 | Int. J. Mod. Phys. A36 (2021) 2150014 | 10.1142/S0217751X21500147 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this article, we introduce a relative P-wave to construct the doubly-charm
axialvector diquark operator, then take the doubly-charm axialvector
(anti)diquark operator as the basic constituent to construct the scalar and
tensor tetraquark currents to study the scalar, axialvector and tensor
fully-charm tetraquark states with the QCD sum rules. We observe that the
ground state $\tilde{A}\tilde{A}$ type tetraquark states and the first radial
excited states of the $AA$ type tetraquark states have almost degenerated
masses, where the $\tilde{A}$ and $A$ stand for the diquark operators with and
without the relative P-wave respectively, the broad structure above the $J/\psi
J/\psi$ threshold maybe consist of several diquark-antidiquark type fully-charm
tetraquark states.
| [
{
"created": "Thu, 10 Sep 2020 12:54:39 GMT",
"version": "v1"
},
{
"created": "Sun, 15 Nov 2020 08:08:31 GMT",
"version": "v2"
}
] | 2021-01-25 | [
[
"Wang",
"Zhi-Gang",
""
]
] | In this article, we introduce a relative P-wave to construct the doubly-charm axialvector diquark operator, then take the doubly-charm axialvector (anti)diquark operator as the basic constituent to construct the scalar and tensor tetraquark currents to study the scalar, axialvector and tensor fully-charm tetraquark states with the QCD sum rules. We observe that the ground state $\tilde{A}\tilde{A}$ type tetraquark states and the first radial excited states of the $AA$ type tetraquark states have almost degenerated masses, where the $\tilde{A}$ and $A$ stand for the diquark operators with and without the relative P-wave respectively, the broad structure above the $J/\psi J/\psi$ threshold maybe consist of several diquark-antidiquark type fully-charm tetraquark states. |
1502.02932 | Wei-Hong Liang | Wei-Hong Liang, R. Molina, Ju-Jun Xie, M. D\"oring, E. Oset | Predictions for the $\bar B^0 \to \bar K^{*0} X (YZ)$ and $\bar B^0_s
\to \phi X (YZ)$ with $X(4160), Y(3940), Z(3930)$ | 10 pages, 6 figures; v2: minor correction, reference added; v3: a new
section added, version to appear in Eur. Phys. J. A | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the decay of $\bar B^0 \to \bar K^{*0} R$ and $\bar B^0_s \to
\phi R$ with $R$ being the $X(4160)$, $Y(3940)$, $Z(3930)$ resonances. Under
the assumption that these states are dynamically generated from the
vector-vector interaction, as has been concluded from several theoretical
studies, we use a reaction mechanism of quark production at the elementary
level, followed by hadronization of one final $q \bar q$ pair into two vectors
and posterior final state interaction of this pair of vector mesons to produce
the resonances. With this procedure we are able to predict five ratios for
these decays, which are closely linked to the dynamical nature of these states,
and also predict the order of magnitude of the branching ratios which we find
of the order of $10^{-4}$, well within the present measurable range. In order
to further test the dynamical nature of these resonances we study the $\bar
B^0_s \to \phi D^* \bar D^*$ and $\bar B^0_s \to \phi D_s^* \bar D_s^*$ decays
close to the $D^* \bar D^*$ and $D_s^* \bar D_s^*$ thresholds and make
predictions for the ratio of the mass distributions in these decays and the
$\bar B^0_s \to \phi R$ decay widths. The measurement of these decays rates can
help unravel the nature of these resonances.
| [
{
"created": "Tue, 10 Feb 2015 15:05:25 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Feb 2015 07:35:00 GMT",
"version": "v2"
},
{
"created": "Tue, 19 May 2015 09:26:34 GMT",
"version": "v3"
}
] | 2015-05-20 | [
[
"Liang",
"Wei-Hong",
""
],
[
"Molina",
"R.",
""
],
[
"Xie",
"Ju-Jun",
""
],
[
"Döring",
"M.",
""
],
[
"Oset",
"E.",
""
]
] | We investigate the decay of $\bar B^0 \to \bar K^{*0} R$ and $\bar B^0_s \to \phi R$ with $R$ being the $X(4160)$, $Y(3940)$, $Z(3930)$ resonances. Under the assumption that these states are dynamically generated from the vector-vector interaction, as has been concluded from several theoretical studies, we use a reaction mechanism of quark production at the elementary level, followed by hadronization of one final $q \bar q$ pair into two vectors and posterior final state interaction of this pair of vector mesons to produce the resonances. With this procedure we are able to predict five ratios for these decays, which are closely linked to the dynamical nature of these states, and also predict the order of magnitude of the branching ratios which we find of the order of $10^{-4}$, well within the present measurable range. In order to further test the dynamical nature of these resonances we study the $\bar B^0_s \to \phi D^* \bar D^*$ and $\bar B^0_s \to \phi D_s^* \bar D_s^*$ decays close to the $D^* \bar D^*$ and $D_s^* \bar D_s^*$ thresholds and make predictions for the ratio of the mass distributions in these decays and the $\bar B^0_s \to \phi R$ decay widths. The measurement of these decays rates can help unravel the nature of these resonances. |
1904.05357 | Masahito Yamazaki | Masahito Yamazaki | From Swampland to Phenomenology and Back | 6 pages, 3 figures, contribution to the 2019 EW session of the 54th
Rencontres de Moriond, v2: references added | null | null | IPMU19-0055 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Swampland conjectures are a set of proposed necessary conditions for a
low-energy effective field theory to have a UV completion inside a theory of
quantum gravity. Swampland conjectures have interesting phenomenological
consequences, and conversely phenomenological considerations are useful
guidelines in sharping our understanding of quantum gravity.
| [
{
"created": "Wed, 10 Apr 2019 18:00:00 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Jul 2019 06:05:31 GMT",
"version": "v2"
}
] | 2019-07-31 | [
[
"Yamazaki",
"Masahito",
""
]
] | Swampland conjectures are a set of proposed necessary conditions for a low-energy effective field theory to have a UV completion inside a theory of quantum gravity. Swampland conjectures have interesting phenomenological consequences, and conversely phenomenological considerations are useful guidelines in sharping our understanding of quantum gravity. |
1705.10505 | Saeed Uddin | Waseem Bashir, Saeed Uddin, Hamid Nanda | Particle Ratios From Strongly Interacting Hadronic Matter | 18 pages, 23 figures | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the particle ratios for a strongly interacting hadronic matter
matter using non-linear Walecka model (NLWM) in relativistic mean-field
approximation. A comparison with Hadron Resonance Gas Model is made.
| [
{
"created": "Tue, 30 May 2017 08:32:28 GMT",
"version": "v1"
}
] | 2017-05-31 | [
[
"Bashir",
"Waseem",
""
],
[
"Uddin",
"Saeed",
""
],
[
"Nanda",
"Hamid",
""
]
] | We calculate the particle ratios for a strongly interacting hadronic matter matter using non-linear Walecka model (NLWM) in relativistic mean-field approximation. A comparison with Hadron Resonance Gas Model is made. |
hep-ph/0107313 | Nobuhiro Maekawa | Nobuhiro Maekawa | A natural solution for the \mu problem with anomalous U(1)_A gauge
symmetry | 7 pages, LATEX, Ver.2:Argument on Giudice-Masiero mechanism is
corrected. Ver.3:Argument on the effect of D-term is added | Phys.Lett. B521 (2001) 42-46 | 10.1016/S0370-2693(01)01179-0 | KUNS-1729 | hep-ph | null | Recently we proposed an attractive scenario of grand unified theories with
anomalous $U(1)_A$ gauge symmetry, in which doublet-triplet splitting is
naturally realized in SO(10) unification using Dimopoulos-Wilczek mechanism and
realistic quark and lepton mass matrices can be obtained in a simple way. In
this paper we show that there is a mechanism in which the doublet Higgs obtains
the supersymmetric mass which is proportional to the SUSY breaking parameters.
This mechanism can be applied easily in the above scenario. The point is that
the mass term, which is forbidden by SUSY zero mechanism, can be induced by
SUSY breaking. The proportional coefficient is controlled by the anomalous
U(1)_A charges.
| [
{
"created": "Tue, 31 Jul 2001 01:51:26 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Aug 2001 05:27:43 GMT",
"version": "v2"
},
{
"created": "Mon, 17 Sep 2001 08:42:21 GMT",
"version": "v3"
}
] | 2009-11-07 | [
[
"Maekawa",
"Nobuhiro",
""
]
] | Recently we proposed an attractive scenario of grand unified theories with anomalous $U(1)_A$ gauge symmetry, in which doublet-triplet splitting is naturally realized in SO(10) unification using Dimopoulos-Wilczek mechanism and realistic quark and lepton mass matrices can be obtained in a simple way. In this paper we show that there is a mechanism in which the doublet Higgs obtains the supersymmetric mass which is proportional to the SUSY breaking parameters. This mechanism can be applied easily in the above scenario. The point is that the mass term, which is forbidden by SUSY zero mechanism, can be induced by SUSY breaking. The proportional coefficient is controlled by the anomalous U(1)_A charges. |
1402.6761 | Nobuhito Maru | C.S. Lim, Nobuhito Maru and Takashi Miura | Is the 126 GeV Higgs Boson Mass Calculable in Gauge-Higgs Unification? | 24 pages, 2 figures, v2: Calculations of corrections to gauge kinetic
terms added, v3: final version to be published | null | 10.1093/ptep/ptv030 | OCU-PHYS 399, KOBE-TH-14-03 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We address a question whether the recently observed Higgs mass $M_{H} = 126$
GeV, of the order of the weak scale $M_{W}$, is calculable as a finite value in
the scnenario of gauge-Higgs unification. In the scenario formulated on a flat
5-dimensional space-time, the Higgs mass is calculable, being protected under
the quantum correction by gauge invariance, though the predicted Higgs mass is
generally too small compared with $M_{W}$. In the 6-dimensional SU(3) model,
however, a suitable orbifolding is known to lead to a mass of the order of
$M_{W}$: $M_{H} = 2M_{W}$ at the tree level, which has some similarity to the
corresponding prediction by the MSSM, $M_{H}$ leq (cos beta) $M_{Z}$. We
demonstrate first by a general argument and secondly by explicit calculations
that, even though the quantum correction to the quartic self-coupling of the
Higgs field is UV-divergent, its deviation from that of $g^{2}$ is calculable,
and therefore two observables, $M_{H}^{2}$ and Delta equiv
$(M_{H}/2M_{W})^{2}-1$, are both calculable in the gauge-Higgs unification
scenario. The implication of the precise value 126 GeV to the compactification
scale and the bulk mass of the matter field in our model is also discussed.
| [
{
"created": "Thu, 27 Feb 2014 01:30:46 GMT",
"version": "v1"
},
{
"created": "Sat, 30 Aug 2014 07:34:36 GMT",
"version": "v2"
},
{
"created": "Mon, 9 Feb 2015 15:00:43 GMT",
"version": "v3"
}
] | 2015-04-01 | [
[
"Lim",
"C. S.",
""
],
[
"Maru",
"Nobuhito",
""
],
[
"Miura",
"Takashi",
""
]
] | We address a question whether the recently observed Higgs mass $M_{H} = 126$ GeV, of the order of the weak scale $M_{W}$, is calculable as a finite value in the scnenario of gauge-Higgs unification. In the scenario formulated on a flat 5-dimensional space-time, the Higgs mass is calculable, being protected under the quantum correction by gauge invariance, though the predicted Higgs mass is generally too small compared with $M_{W}$. In the 6-dimensional SU(3) model, however, a suitable orbifolding is known to lead to a mass of the order of $M_{W}$: $M_{H} = 2M_{W}$ at the tree level, which has some similarity to the corresponding prediction by the MSSM, $M_{H}$ leq (cos beta) $M_{Z}$. We demonstrate first by a general argument and secondly by explicit calculations that, even though the quantum correction to the quartic self-coupling of the Higgs field is UV-divergent, its deviation from that of $g^{2}$ is calculable, and therefore two observables, $M_{H}^{2}$ and Delta equiv $(M_{H}/2M_{W})^{2}-1$, are both calculable in the gauge-Higgs unification scenario. The implication of the precise value 126 GeV to the compactification scale and the bulk mass of the matter field in our model is also discussed. |
1306.0845 | John LoSecco | John LoSecco | Optimization for Mass Hierarchy | 3+ pages, 6 figures | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Delta m^2_13 oscillation frequency for reactor neutrinos differs by 6.4%
between normal and inverted mass hierarchy. This frequency difference
accumulates to a phase difference over distance and time. The optimal distance
is when the maximum phase difference between hierarchies occurs near the peak
in the observable reactor neutrino spectrum. Added citations to some related
recent work.
| [
{
"created": "Tue, 4 Jun 2013 16:22:08 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Jun 2013 17:15:26 GMT",
"version": "v2"
}
] | 2013-06-24 | [
[
"LoSecco",
"John",
""
]
] | The Delta m^2_13 oscillation frequency for reactor neutrinos differs by 6.4% between normal and inverted mass hierarchy. This frequency difference accumulates to a phase difference over distance and time. The optimal distance is when the maximum phase difference between hierarchies occurs near the peak in the observable reactor neutrino spectrum. Added citations to some related recent work. |
1109.1181 | Sreemoyee Sarkar | Mahatsab Mandal, Sreemoyee Sarkar, Pradip Roy and Abhee K.
Dutt-Mazumder | Energy loss due to field fluctuations in a two-stream QCD plasma | 4 pages, 2 figures | null | null | null | hep-ph nucl-th physics.plasm-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive the expression for the collisional energy loss in two stream plasma
induced by the fluctuating chromoelectric field. It is revealed that the main
contribution here comes from the unstable modes which grow exponentially with
time. A strong direction dependence of the energy loss has also been
demonstrated.
| [
{
"created": "Tue, 6 Sep 2011 13:38:28 GMT",
"version": "v1"
}
] | 2011-09-07 | [
[
"Mandal",
"Mahatsab",
""
],
[
"Sarkar",
"Sreemoyee",
""
],
[
"Roy",
"Pradip",
""
],
[
"Dutt-Mazumder",
"Abhee K.",
""
]
] | We derive the expression for the collisional energy loss in two stream plasma induced by the fluctuating chromoelectric field. It is revealed that the main contribution here comes from the unstable modes which grow exponentially with time. A strong direction dependence of the energy loss has also been demonstrated. |
hep-ph/9209245 | Andy Cohen | A. Cohen and A. Nelson | Supersymmtric Baryogenesis | 14 pages 3 fig.,BUHEP-92-20 | Phys.Lett.B297:111-117,1992 | 10.1016/0370-2693(92)91078-N | null | hep-ph | null | Requiring that the baryon number of the universe be generated by anomalous
electroweak interactions places strong constraints on the minimal
supersymmetric standard model. In particular, the electric dipole moment of the
neutron must be greater than $10^{-27}$e-cm. Improvement of the current
experimental bound on the neutron's electric dipole moment by one order of
magnitude would constrain the lightest chargino to be lighter than 88 GeV, and
the the lightest neutralino to be lighter than 44 GeV. In extensions of this
model with gauge singlet superfields all of these bounds are eliminated.
| [
{
"created": "Wed, 16 Sep 1992 17:45:14 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Cohen",
"A.",
""
],
[
"Nelson",
"A.",
""
]
] | Requiring that the baryon number of the universe be generated by anomalous electroweak interactions places strong constraints on the minimal supersymmetric standard model. In particular, the electric dipole moment of the neutron must be greater than $10^{-27}$e-cm. Improvement of the current experimental bound on the neutron's electric dipole moment by one order of magnitude would constrain the lightest chargino to be lighter than 88 GeV, and the the lightest neutralino to be lighter than 44 GeV. In extensions of this model with gauge singlet superfields all of these bounds are eliminated. |
1305.6610 | Gl\'auber Carvalho Dorsch | G. C. Dorsch, S. J. Huber and J. M. No | A strong electroweak phase transition in the 2HDM after LHC8 | null | null | 10.1007/JHEP10(2013)029 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The nature of the electroweak phase transition in two-Higgs-doublet models is
revisited in light of the recent LHC results. A scan over an extensive region
of their parameter space is performed, showing that a strongly first-order
phase transition favours a light neutral scalar with SM-like properties,
together with a heavy pseudo-scalar (m_A^0 > 400 GeV) and a mass hierarchy in
the scalar sector, m_H^+ < m_H^0 < m_A^0. We also investigate the h^0 -> gamma
gamma decay channel and find that an enhancement in the branching ratio is
allowed, and in some cases even preferred, when a strongly first-order phase
transition is required.
| [
{
"created": "Tue, 28 May 2013 20:00:03 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Oct 2013 17:35:59 GMT",
"version": "v2"
}
] | 2013-10-30 | [
[
"Dorsch",
"G. C.",
""
],
[
"Huber",
"S. J.",
""
],
[
"No",
"J. M.",
""
]
] | The nature of the electroweak phase transition in two-Higgs-doublet models is revisited in light of the recent LHC results. A scan over an extensive region of their parameter space is performed, showing that a strongly first-order phase transition favours a light neutral scalar with SM-like properties, together with a heavy pseudo-scalar (m_A^0 > 400 GeV) and a mass hierarchy in the scalar sector, m_H^+ < m_H^0 < m_A^0. We also investigate the h^0 -> gamma gamma decay channel and find that an enhancement in the branching ratio is allowed, and in some cases even preferred, when a strongly first-order phase transition is required. |
2005.05332 | Cyril Creque-Sarbinowski | Cyril Creque-Sarbinowski, Jeffrey Hyde and Marc Kamionkowski | Resonant Neutrino Self-Interactions | 11 pages, 8 figures | Phys. Rev. D 103, 023527 (2021) | 10.1103/PhysRevD.103.023527 | null | hep-ph astro-ph.CO astro-ph.HE nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | If neutrinos have self-interactions, these will induce scatterings between
astrophysical and cosmic neutrinos. Prior work proposed to look for possible
resulting resonance features in astrophysical neutrino spectra in order to seek
a neutrino self-interaction which can be either diagonal in the neutrino flavor
space or couple different neutrino flavors. The calculation of the
astrophysical spectra involves either a Monte Carlo simulation or a
computationally intensive numerical integration of an
integro-partial-differential equation. As a result only limited regions of the
neutrino self-interaction parameter space have been explored, and only
flavor-diagonal self-interactions have been considered. Here, we present a
fully analytic form for the astrophysical neutrino spectra for arbitrary
neutrino number and arbitrary self-coupling matrix that accurately obtains the
resonance features in the observable neutrino spectra. The results can be
applied to calculations of the diffuse supernova neutrino background and of the
spectrum from high-energy astrophysical neutrino sources. We illustrate with a
few examples.
| [
{
"created": "Mon, 11 May 2020 18:00:01 GMT",
"version": "v1"
}
] | 2021-01-27 | [
[
"Creque-Sarbinowski",
"Cyril",
""
],
[
"Hyde",
"Jeffrey",
""
],
[
"Kamionkowski",
"Marc",
""
]
] | If neutrinos have self-interactions, these will induce scatterings between astrophysical and cosmic neutrinos. Prior work proposed to look for possible resulting resonance features in astrophysical neutrino spectra in order to seek a neutrino self-interaction which can be either diagonal in the neutrino flavor space or couple different neutrino flavors. The calculation of the astrophysical spectra involves either a Monte Carlo simulation or a computationally intensive numerical integration of an integro-partial-differential equation. As a result only limited regions of the neutrino self-interaction parameter space have been explored, and only flavor-diagonal self-interactions have been considered. Here, we present a fully analytic form for the astrophysical neutrino spectra for arbitrary neutrino number and arbitrary self-coupling matrix that accurately obtains the resonance features in the observable neutrino spectra. The results can be applied to calculations of the diffuse supernova neutrino background and of the spectrum from high-energy astrophysical neutrino sources. We illustrate with a few examples. |
hep-ph/0311241 | Carlo Giunti | Carlo Giunti | Theory of Neutrino Oscillations | 5 pages, talk presented at IFAE 2003, Lecce, 23-26 April 2003 | null | null | null | hep-ph | null | We review critically the main assumptions on which the standard theory of
neutrino oscillations is based. We show that all assumptions are realistic,
except the so-called "equal momentum assumption", which however is irrelevant.
We conclude that the standard expression for the probability of neutrino
oscillations is robust.
| [
{
"created": "Wed, 19 Nov 2003 13:19:07 GMT",
"version": "v1"
},
{
"created": "Fri, 6 Feb 2004 11:16:30 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Giunti",
"Carlo",
""
]
] | We review critically the main assumptions on which the standard theory of neutrino oscillations is based. We show that all assumptions are realistic, except the so-called "equal momentum assumption", which however is irrelevant. We conclude that the standard expression for the probability of neutrino oscillations is robust. |
2212.12780 | Phuoc Ha | Phuoc Ha | Some applications of the Eikonal model with Coulomb and curvature
corrections in $pp$ and $\bar{p}p$ scattering | 10 pages, 3 figures | null | 10.1103/PhysRevD.107.094016 | null | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | Using a simple eikonal approach to the treatment of Coulomb-nuclear
interference and form-factors effects and taking into account the curvature
effects in high-energy $pp$ and $\bar{p}p$ scattering, we determine the basic
parameters $B$, $\rho$ and $\sigma_{\rm tot}$ from fits to experiment at
$W=\sqrt s=$ 53 GeV, 62.3 GeV, 8 TeV, and 13 TeV. We then investigate the
differential cross sections in the dip region for $pp$ and $\bar{p}p$ elastic
scattering at $W=$ 53 GeV and 1.96 TeV. We find that the results of the basic
parameters calculated using the simple eikonal approach agree well with the
values determined in other analyses. We find that Coulomb effects are
significant in the dip region at 53 GeV and 1.96 TeV, and must be taken into
account in searches for odderon effects through cross section differences in
that energy region.
| [
{
"created": "Sat, 24 Dec 2022 17:03:16 GMT",
"version": "v1"
},
{
"created": "Mon, 15 May 2023 18:51:10 GMT",
"version": "v2"
}
] | 2023-05-24 | [
[
"Ha",
"Phuoc",
""
]
] | Using a simple eikonal approach to the treatment of Coulomb-nuclear interference and form-factors effects and taking into account the curvature effects in high-energy $pp$ and $\bar{p}p$ scattering, we determine the basic parameters $B$, $\rho$ and $\sigma_{\rm tot}$ from fits to experiment at $W=\sqrt s=$ 53 GeV, 62.3 GeV, 8 TeV, and 13 TeV. We then investigate the differential cross sections in the dip region for $pp$ and $\bar{p}p$ elastic scattering at $W=$ 53 GeV and 1.96 TeV. We find that the results of the basic parameters calculated using the simple eikonal approach agree well with the values determined in other analyses. We find that Coulomb effects are significant in the dip region at 53 GeV and 1.96 TeV, and must be taken into account in searches for odderon effects through cross section differences in that energy region. |
2202.05276 | Matthias Steinhauser | Matteo Fael, Fabian Lange, Kay Schoenwald, Matthias Steinhauser | Massive vector form factors to three loops | 7 pages | null | 10.1103/PhysRevLett.128.172003 | TTP22-009, P3H-22-016 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the three-loop non-singlet corrections to the photon-quark form
factors taking into account the full dependence on the virtuality of the photon
and the quark mass. We combine the method of differential equations in an
effective way with expansions around regular and singular points. This allows
us to obtain results for the form factors with an accuracy of about eight to
twelve digits in the whole kinematic range.
| [
{
"created": "Thu, 10 Feb 2022 19:00:00 GMT",
"version": "v1"
}
] | 2022-05-11 | [
[
"Fael",
"Matteo",
""
],
[
"Lange",
"Fabian",
""
],
[
"Schoenwald",
"Kay",
""
],
[
"Steinhauser",
"Matthias",
""
]
] | We compute the three-loop non-singlet corrections to the photon-quark form factors taking into account the full dependence on the virtuality of the photon and the quark mass. We combine the method of differential equations in an effective way with expansions around regular and singular points. This allows us to obtain results for the form factors with an accuracy of about eight to twelve digits in the whole kinematic range. |
1211.1026 | David Atwood | David Atwood and Amarjit Soni | Searching for the Origin of CP violation in Cabibbo Suppressed D-meson
Decays | 21 pages, 4 figures, 1 table; Version to appear in journal | null | 10.1093/ptep/ptt065 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recent evidence of large direct CP violation in D0 decay at LHCb suggests
that such CP studies may become an important avenue for understanding CP. In
this paper, we make several suggestions to try to clarify the role of new
physics in these results. We propose that the enhancement needed in the
Standard Model to attribute the observed CP violation in D to two pseudoscalar
modes may not operate for inclusive final states where asymmetries will likely
approximate the quark level expectation. Experimentally testing this principle
requires a search for CP asymmetries in final states containing K and K-bar
with a total energy of less than M_D. We also propose that CP asymmetries may
be enhanced in modes where the tree is color suppressed. In particular, the
final state rho0 rho0 is of special interest; similarly Ds-> rho0 K+ and rho0
K*+ likewise appear interesting. We discuss how isospin symmetry yields
observables sensitive to certain classes of new physics and suppressed in the
Standard Model. Some modes considered in this context are D-> pi pi, rho pi,
rho rho as well as Ds-> K* pi. We also consider how such analysis may
eventually be supplemented by information about the weak phases in D0 decay. In
order to obtain this information experimentally, we consider various methods
for preparing an initial state which is a quantum mechanical mixture of D0 and
D0-bar. This may be done through the use of natural D0 D0-bar oscillations;
observing D0-mesons which arise from Bd or Bs mesons which themselves are
oscillating or from quantum correlations in D0 pairs which arise from either
psi" decay or B-meson decay. Observing CP violation in the magnitudes of decay
amplitudes should be within the capability of experiments in the near future
however obtaining the weak phases through the methods we discuss will likely
require future generations of machines.
| [
{
"created": "Mon, 5 Nov 2012 21:00:13 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Jan 2013 23:05:31 GMT",
"version": "v2"
},
{
"created": "Tue, 9 Jul 2013 18:51:09 GMT",
"version": "v3"
}
] | 2014-05-07 | [
[
"Atwood",
"David",
""
],
[
"Soni",
"Amarjit",
""
]
] | The recent evidence of large direct CP violation in D0 decay at LHCb suggests that such CP studies may become an important avenue for understanding CP. In this paper, we make several suggestions to try to clarify the role of new physics in these results. We propose that the enhancement needed in the Standard Model to attribute the observed CP violation in D to two pseudoscalar modes may not operate for inclusive final states where asymmetries will likely approximate the quark level expectation. Experimentally testing this principle requires a search for CP asymmetries in final states containing K and K-bar with a total energy of less than M_D. We also propose that CP asymmetries may be enhanced in modes where the tree is color suppressed. In particular, the final state rho0 rho0 is of special interest; similarly Ds-> rho0 K+ and rho0 K*+ likewise appear interesting. We discuss how isospin symmetry yields observables sensitive to certain classes of new physics and suppressed in the Standard Model. Some modes considered in this context are D-> pi pi, rho pi, rho rho as well as Ds-> K* pi. We also consider how such analysis may eventually be supplemented by information about the weak phases in D0 decay. In order to obtain this information experimentally, we consider various methods for preparing an initial state which is a quantum mechanical mixture of D0 and D0-bar. This may be done through the use of natural D0 D0-bar oscillations; observing D0-mesons which arise from Bd or Bs mesons which themselves are oscillating or from quantum correlations in D0 pairs which arise from either psi" decay or B-meson decay. Observing CP violation in the magnitudes of decay amplitudes should be within the capability of experiments in the near future however obtaining the weak phases through the methods we discuss will likely require future generations of machines. |
2306.10973 | Liang Chen | Liang Chen, Ta-Wei Chan, Thomas W. Kephart, Wai Yee Keung, Tzu-Chiang
Yuan | GUT origins of general electroweak multiplets and their oblique
parameters | new references added | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We survey the scalar electroweak multiplets that can originate from a grand
unified theory (GUT) like $SU(5)$, $SO(10)$ or $E_6$. We compute the oblique
parameters $S$, $T$ and $U$ for a general scalar electroweak multiplet and then
apply the results to the leptoquark, as well as the color sextet and octet
cases, allowed by the GUT survey. Constraints from precision measurement data
of the Standard Model $W$ boson mass and $\rho$ parameter to the mass
splittings within each of these multiplets are presented. Extension to general
vector electroweak multiplets is briefly discussed.
| [
{
"created": "Mon, 19 Jun 2023 14:34:36 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Jun 2023 05:29:32 GMT",
"version": "v2"
}
] | 2023-06-29 | [
[
"Chen",
"Liang",
""
],
[
"Chan",
"Ta-Wei",
""
],
[
"Kephart",
"Thomas W.",
""
],
[
"Keung",
"Wai Yee",
""
],
[
"Yuan",
"Tzu-Chiang",
""
]
] | We survey the scalar electroweak multiplets that can originate from a grand unified theory (GUT) like $SU(5)$, $SO(10)$ or $E_6$. We compute the oblique parameters $S$, $T$ and $U$ for a general scalar electroweak multiplet and then apply the results to the leptoquark, as well as the color sextet and octet cases, allowed by the GUT survey. Constraints from precision measurement data of the Standard Model $W$ boson mass and $\rho$ parameter to the mass splittings within each of these multiplets are presented. Extension to general vector electroweak multiplets is briefly discussed. |
1412.8714 | Ayon Patra Dr. | K. S. Babu and Ayon Patra | Higgs Boson Spectra in Supersymmetric Left-Right Models | 52 pages, 13 figures | Phys. Rev. D 93, 055030 (2016) | 10.1103/PhysRevD.93.055030 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a comprehensive analysis of the Higgs boson spectra in several
versions of the supersymmetric left--right model based on the gauge symmetry
$SU(3)_c \times SU(2)_L \times SU(2)_R \times U(1)_{B-L}$. A variety of
symmetry breaking sectors are studied, with a focus on the constraints placed
on model parameters by the lightest neutral CP even Higgs boson mass $M_h$. The
breaking of $SU(2)_R$ symmetry is achieved by Higgs fields transforming either
as triplets or doublets, and the electroweak symmetry breaking is triggered by
either bi--doublets or doublets. The Higgs potential is analyzed with or
without a gauge singlet Higgs field present. Seesaw models of Type I and Type
II, inverse seesaw models, universal seesaw models and an $E_6$ inspired
alternate left--right model are included in our analysis. Several of these
models lead to the tree--level relation $M_h \leq \sqrt{2}\,m_W$ (rather than
$M_h \leq m_Z$ that arises in the MSSM), realized when the $SU(2)_R$ symmetry
breaking scale is of order TeV. With such an enhanced upper limit, it becomes
possible to accommodate a Higgs boson of mass 126 GeV with relatively light
stops that mix negligibly. In models with Higgs triplets, a doubly charged
scalar remains light below a TeV with its mass arising entirely from radiative
corrections. We carry out the complete one--loop calculation for its mass
induced by the Majorana Yukawa couplings and show the consistency of the
framework. We argue that these models prefer a low $SU(2)_R$ breaking scale.
Other theoretical and phenomenological implications of these models are briefly
discussed.
| [
{
"created": "Tue, 30 Dec 2014 18:14:12 GMT",
"version": "v1"
}
] | 2016-03-30 | [
[
"Babu",
"K. S.",
""
],
[
"Patra",
"Ayon",
""
]
] | We present a comprehensive analysis of the Higgs boson spectra in several versions of the supersymmetric left--right model based on the gauge symmetry $SU(3)_c \times SU(2)_L \times SU(2)_R \times U(1)_{B-L}$. A variety of symmetry breaking sectors are studied, with a focus on the constraints placed on model parameters by the lightest neutral CP even Higgs boson mass $M_h$. The breaking of $SU(2)_R$ symmetry is achieved by Higgs fields transforming either as triplets or doublets, and the electroweak symmetry breaking is triggered by either bi--doublets or doublets. The Higgs potential is analyzed with or without a gauge singlet Higgs field present. Seesaw models of Type I and Type II, inverse seesaw models, universal seesaw models and an $E_6$ inspired alternate left--right model are included in our analysis. Several of these models lead to the tree--level relation $M_h \leq \sqrt{2}\,m_W$ (rather than $M_h \leq m_Z$ that arises in the MSSM), realized when the $SU(2)_R$ symmetry breaking scale is of order TeV. With such an enhanced upper limit, it becomes possible to accommodate a Higgs boson of mass 126 GeV with relatively light stops that mix negligibly. In models with Higgs triplets, a doubly charged scalar remains light below a TeV with its mass arising entirely from radiative corrections. We carry out the complete one--loop calculation for its mass induced by the Majorana Yukawa couplings and show the consistency of the framework. We argue that these models prefer a low $SU(2)_R$ breaking scale. Other theoretical and phenomenological implications of these models are briefly discussed. |
hep-ph/0512069 | Michael Dinsdale | M. J. Dinsdale | Scale Optimisation and Event Shapes in Deep-Inelastic Scattering | 21 pages, 6 figures | null | null | MZ-TH/05-29 | hep-ph | null | We study the effect of optimising the renormalisation and factorisation
scales on perturbative calculations of event shape means defined in the Breit
frame of ep DIS. Unlike in the case of e^+e^- event shape means, this has only
a small effect on the NLO QCD predictions and a large power correction is still
required to fit the data. However, if separate renormalization scales are
introduced for the quark- and gluon-initiated sub-processes the optimisation
has a much larger effect and greatly reduces the size of the required power
corrections. Unfortunately, there are then problems fitting the low energy data
for some observables.
| [
{
"created": "Mon, 5 Dec 2005 20:43:35 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dinsdale",
"M. J.",
""
]
] | We study the effect of optimising the renormalisation and factorisation scales on perturbative calculations of event shape means defined in the Breit frame of ep DIS. Unlike in the case of e^+e^- event shape means, this has only a small effect on the NLO QCD predictions and a large power correction is still required to fit the data. However, if separate renormalization scales are introduced for the quark- and gluon-initiated sub-processes the optimisation has a much larger effect and greatly reduces the size of the required power corrections. Unfortunately, there are then problems fitting the low energy data for some observables. |
hep-ph/0204161 | Bruce H. J. McKellar | S. R. Choudhury, G. C. Joshi, S. Mahajan, B. H. J. McKellar | Probing large distance higher dimensional gravity from lensing data | 6 pages, 1 figure, added references | Astropart.Phys.21:559-563,2004 | 10.1016/j.astropartphys.2004.04.001 | null | hep-ph | null | The modifications induced in the standard weak-lensing formula if Newtonian
gravity differs from inverse square law at large distances are studied. The
possibility of putting bounds on the mass of gravitons from lensing data is
explored. A bound on graviton mass, esitmated to be about 100 Mpc$^{-1}$ is
obtained from analysis of some recent data on gravitational lensing.
| [
{
"created": "Mon, 15 Apr 2002 01:32:05 GMT",
"version": "v1"
},
{
"created": "Mon, 6 May 2002 07:21:42 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Choudhury",
"S. R.",
""
],
[
"Joshi",
"G. C.",
""
],
[
"Mahajan",
"S.",
""
],
[
"McKellar",
"B. H. J.",
""
]
] | The modifications induced in the standard weak-lensing formula if Newtonian gravity differs from inverse square law at large distances are studied. The possibility of putting bounds on the mass of gravitons from lensing data is explored. A bound on graviton mass, esitmated to be about 100 Mpc$^{-1}$ is obtained from analysis of some recent data on gravitational lensing. |
hep-ph/0310025 | Matthew Dorsten | Matthew P. Dorsten (Caltech) | Perturbative corrections to curvature sum rules | 19 pages, 4 figures; minor clarifications, additional figure | Phys.Rev. D70 (2004) 096013 | 10.1103/PhysRevD.70.096013 | CALT-68-2450 | hep-ph | null | Two new sum rules were recently discovered by Le Yaouanc et al. by applying
the operator product expansion to the nonforward matrix element of a
time-ordered product of $b \to c$ currents in the heavy-quark limit of QCD.
They lead to the constraints $\sigma^2 > 5\rho^2/4$ and $\sigma^2 >
3(\rho^2)^2/5 + 4\rho^2/5$ on the curvature of the $\bar{B} \to D^{(*)}$
Isgur-Wise function, both of which imply the absolute lower bound $\sigma^2 >
15/16$ when combined with the Uraltsev bound $\rho^2 > 3/4$ on the slope. This
paper calculates order $\alpha_s$ corrections to these bounds, increasing the
accuracy of the resultant constraints on the physical form factors. The latter
may have implications for the determination of $|V_{cb}|$ from exclusive
semileptonic $B$ meson decays.
| [
{
"created": "Thu, 2 Oct 2003 19:44:46 GMT",
"version": "v1"
},
{
"created": "Thu, 2 Dec 2004 22:05:51 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Dorsten",
"Matthew P.",
"",
"Caltech"
]
] | Two new sum rules were recently discovered by Le Yaouanc et al. by applying the operator product expansion to the nonforward matrix element of a time-ordered product of $b \to c$ currents in the heavy-quark limit of QCD. They lead to the constraints $\sigma^2 > 5\rho^2/4$ and $\sigma^2 > 3(\rho^2)^2/5 + 4\rho^2/5$ on the curvature of the $\bar{B} \to D^{(*)}$ Isgur-Wise function, both of which imply the absolute lower bound $\sigma^2 > 15/16$ when combined with the Uraltsev bound $\rho^2 > 3/4$ on the slope. This paper calculates order $\alpha_s$ corrections to these bounds, increasing the accuracy of the resultant constraints on the physical form factors. The latter may have implications for the determination of $|V_{cb}|$ from exclusive semileptonic $B$ meson decays. |
hep-ph/9705326 | Mihail Kopysov | M. Yu. Kopysov and Yu. E. Pokrovsky (Russian Research Center
''Kurchatov Institute'', Moscow, Russia) | Possible Asymmetry of Particle Distribution Around Axes of Hard Jets in
Ultrarelativistic Heavy Ion Collisions | 15 pages, LaTeX, 3 LaTeX figures, submitted to Physics Letters B | null | null | null | hep-ph | null | We discuss a possible new manifestation of the formation of an initial
nonequilibrium flux tube stage in high energy heavy ion collisions. It is shown
that a strong asymmetry in particle distributions around axes of
hard-transverse jets takes place due to a large difference between longitudinal
and transverse forces acting on the hardly scattered quarks or gluons crossing
the flux tubes.
| [
{
"created": "Thu, 15 May 1997 14:53:04 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kopysov",
"M. Yu.",
"",
"Russian Research Center\n ''Kurchatov Institute'', Moscow, Russia"
],
[
"Pokrovsky",
"Yu. E.",
"",
"Russian Research Center\n ''Kurchatov Institute'', Moscow, Russia"
]
] | We discuss a possible new manifestation of the formation of an initial nonequilibrium flux tube stage in high energy heavy ion collisions. It is shown that a strong asymmetry in particle distributions around axes of hard-transverse jets takes place due to a large difference between longitudinal and transverse forces acting on the hardly scattered quarks or gluons crossing the flux tubes. |
hep-ph/9907263 | Marc Schumann | M. Schumann, R.J. Lindebaum and R.D. Viollier | Hadron masses in cavity quantum chromodynamics to order $\alpha_s^2$ | 15 pages, 2 figures | null | 10.1007/s100520050025 | null | hep-ph | null | The non-divergent diagrams describing two-gluon exchange and annihilation
between quarks and antiquarks are calculated in the Feynman gauge, based on
quantum chromodynamics in a spherical cavity. Using the experimental $N$,
$\Delta$, $\Omega$, and $\rho$ masses to fit the free parameters of the M.I.T.\
bag model, the predicted states agree very well with the observed low-lying
hadrons. As expected, the two-gluon annihilation graphs lift the degeneracy of
the $\pi$ and $\eta$, while the $\rho$ and $\omega$ remain degenerate.
Diagonalizing the $\eta - \eta'$ subspace Hamiltonian yields a very good value
for the mass of the $\eta$ meson.
| [
{
"created": "Wed, 7 Jul 1999 10:16:10 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Apr 2000 12:03:19 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Schumann",
"M.",
""
],
[
"Lindebaum",
"R. J.",
""
],
[
"Viollier",
"R. D.",
""
]
] | The non-divergent diagrams describing two-gluon exchange and annihilation between quarks and antiquarks are calculated in the Feynman gauge, based on quantum chromodynamics in a spherical cavity. Using the experimental $N$, $\Delta$, $\Omega$, and $\rho$ masses to fit the free parameters of the M.I.T.\ bag model, the predicted states agree very well with the observed low-lying hadrons. As expected, the two-gluon annihilation graphs lift the degeneracy of the $\pi$ and $\eta$, while the $\rho$ and $\omega$ remain degenerate. Diagonalizing the $\eta - \eta'$ subspace Hamiltonian yields a very good value for the mass of the $\eta$ meson. |
2404.15711 | Alexander Karlberg | Valerio Bertone, Alexander Karlberg | Benchmark of deep-inelastic-scattering structure functions at
$\mathcal{O}(\alpha_s^3)$ | 21 pages, benchmark code is available at
https://github.com/alexanderkarlberg/n3lo-structure-function-benchmarks | Eur. Phys. J. C 84, 774 (2024) | 10.1140/epjc/s10052-024-13133-6 | CERN-TH-2024-018 | hep-ph hep-ex hep-th | http://creativecommons.org/licenses/by/4.0/ | We present a benchmark comparison of the massless inclusive
deep-inelastic-scattering (DIS) structure functions up to
$\mathcal{O}(\alpha_s^3)$ in perturbative QCD. The comparison is performed
using the codes APFEL++ and HOPPET within the framework of the
variable-flavour-number scheme and over a broad kinematic range relevant to the
extraction of parton distribution functions. We provide results for both the
single structure functions and the reduced cross sections in both neutral- and
charged-current DIS. Look-up tables for future reference are included, and we
also release the code used for the benchmark.
| [
{
"created": "Wed, 24 Apr 2024 08:03:57 GMT",
"version": "v1"
}
] | 2024-08-08 | [
[
"Bertone",
"Valerio",
""
],
[
"Karlberg",
"Alexander",
""
]
] | We present a benchmark comparison of the massless inclusive deep-inelastic-scattering (DIS) structure functions up to $\mathcal{O}(\alpha_s^3)$ in perturbative QCD. The comparison is performed using the codes APFEL++ and HOPPET within the framework of the variable-flavour-number scheme and over a broad kinematic range relevant to the extraction of parton distribution functions. We provide results for both the single structure functions and the reduced cross sections in both neutral- and charged-current DIS. Look-up tables for future reference are included, and we also release the code used for the benchmark. |
1301.5787 | Emanuele Pace | Emanuele Pace, Giovanni Salme', Sergio Scopetta, Alessio Del Dotto,
Matteo Rinaldi | Neutron Transverse-Momentum Distributions and Polarized 3He within
Light-Front Hamiltonian Dynamics | 4 pages, 2 figures, Presented at the 20th International IUPAP
Conference on Few-Body Problems in Physics, 20 - 25 August, 2012, Fukuoka,
Japan | null | 10.1007/s00601-013-0679-0 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The possibility to extract the quark transverse-momentum distributions in the
neutron from semi-inclusive deep inelastic electron scattering off polarized
3He is illustrated through an impulse approximation analysis in the Bjorken
limit. The generalization of the analysis at finite momentum transfers in a
Poincare' covariant framework is outlined. The definition of the light-front
spin-dependent spectral function of a J=1/2 system allows us to show that
within the light-front dynamics only three of the six leading twist T-even
transverse-momentum distributions are independent.
| [
{
"created": "Thu, 24 Jan 2013 14:18:46 GMT",
"version": "v1"
}
] | 2015-06-12 | [
[
"Pace",
"Emanuele",
""
],
[
"Salme'",
"Giovanni",
""
],
[
"Scopetta",
"Sergio",
""
],
[
"Del Dotto",
"Alessio",
""
],
[
"Rinaldi",
"Matteo",
""
]
] | The possibility to extract the quark transverse-momentum distributions in the neutron from semi-inclusive deep inelastic electron scattering off polarized 3He is illustrated through an impulse approximation analysis in the Bjorken limit. The generalization of the analysis at finite momentum transfers in a Poincare' covariant framework is outlined. The definition of the light-front spin-dependent spectral function of a J=1/2 system allows us to show that within the light-front dynamics only three of the six leading twist T-even transverse-momentum distributions are independent. |
1102.4068 | Jordy Vries de | J. de Vries, E. Mereghetti, R.G.E. Timmermans, U. van Kolck | Parity- and Time-Reversal-Violating Form Factors of the Deuteron | null | Phys.Rev.Lett.107:091804,2011 | 10.1103/PhysRevLett.107.091804 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the electric-dipole and magnetic-quadrupole form factors of the
deuteron that arise as a low-energy manifestation of parity and time-reversal
violation in quark-gluon interactions of effective dimension four and six: the
QCD vacuum angle, the quark electric and chromo-electric dipole moments, and
the gluon chromo-electric dipole moment. Within the framework of two-flavor
chiral perturbation theory, we show that the relative sizes of the
corresponding moments allow an identification of the symmetry-breaking source.
| [
{
"created": "Sun, 20 Feb 2011 13:34:49 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Sep 2011 15:23:01 GMT",
"version": "v2"
}
] | 2011-09-07 | [
[
"de Vries",
"J.",
""
],
[
"Mereghetti",
"E.",
""
],
[
"Timmermans",
"R. G. E.",
""
],
[
"van Kolck",
"U.",
""
]
] | We calculate the electric-dipole and magnetic-quadrupole form factors of the deuteron that arise as a low-energy manifestation of parity and time-reversal violation in quark-gluon interactions of effective dimension four and six: the QCD vacuum angle, the quark electric and chromo-electric dipole moments, and the gluon chromo-electric dipole moment. Within the framework of two-flavor chiral perturbation theory, we show that the relative sizes of the corresponding moments allow an identification of the symmetry-breaking source. |
hep-ph/0510410 | Anisovich Vladimir V. | V.V. Anisovich, L.G. Dakhno, M.A. Matveev, V.A. Nikonov and A.V.
Sarantsev | Quark--antiquark states and their radiative transitions in terms of the
spectral integral equation. {\Huge I.} Bottomonia | 43 pages, 13 figures | Phys.Atom.Nucl.70:63-92,2007 | 10.1134/S1063778807010097 | null | hep-ph | null | In the framework of the spectral integral equation, we consider the $b\bar b$
states and their radiative transitions. We reconstruct the $b\bar b$
interaction on the basis of data for the levels of the bottomonium states with
$J^{PC}=0^{-+}$, $1^{--}$, $0^{++}$, $1^{++}$, $2^{++}$ as well as the data for
the radiative transitions $\Upsilon(3S) \to\gamma\chi_{bJ}(2P) $ and
$\Upsilon(2S) \to\gamma \chi_{bJ}(1P) $ with $J=0,1,2$. We calculate
bottomonium levels with the radial quantum numbers $n\le 6$, their wave
functions and corresponding radiative transitions. The ratios
$Br[\chi_{bJ}(2P)\to\gamma\Upsilon(2S)]/Br[\chi_{bJ}(2P)\to\gamma\Upsilon(1S)]$
for $J=0,1,2$ are found in the agreement with data. We determine the $b\bar b$
component of the photon wave function using the data for the $e^+e^-$
annihilation, $e^+e^- \to\Upsilon(9460)$, $\Upsilon(10023)$, $\Upsilon(10036)$,
$\Upsilon(10580)$, $ \Upsilon(10865)$, $\Upsilon(11019)$, and predict partial
widths of the two-photon decays $\eta_{b0}\to\ggam$, $\chi_{b0}\to\ggam$,
$\chi_{b2}\to\ggam$ for the radial excitation states below $B\bar B$ threshold
($n\le 3$).
| [
{
"created": "Mon, 31 Oct 2005 10:10:23 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Nov 2005 09:50:43 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Anisovich",
"V. V.",
""
],
[
"Dakhno",
"L. G.",
""
],
[
"Matveev",
"M. A.",
""
],
[
"Nikonov",
"V. A.",
""
],
[
"Sarantsev",
"A. V.",
""
]
] | In the framework of the spectral integral equation, we consider the $b\bar b$ states and their radiative transitions. We reconstruct the $b\bar b$ interaction on the basis of data for the levels of the bottomonium states with $J^{PC}=0^{-+}$, $1^{--}$, $0^{++}$, $1^{++}$, $2^{++}$ as well as the data for the radiative transitions $\Upsilon(3S) \to\gamma\chi_{bJ}(2P) $ and $\Upsilon(2S) \to\gamma \chi_{bJ}(1P) $ with $J=0,1,2$. We calculate bottomonium levels with the radial quantum numbers $n\le 6$, their wave functions and corresponding radiative transitions. The ratios $Br[\chi_{bJ}(2P)\to\gamma\Upsilon(2S)]/Br[\chi_{bJ}(2P)\to\gamma\Upsilon(1S)]$ for $J=0,1,2$ are found in the agreement with data. We determine the $b\bar b$ component of the photon wave function using the data for the $e^+e^-$ annihilation, $e^+e^- \to\Upsilon(9460)$, $\Upsilon(10023)$, $\Upsilon(10036)$, $\Upsilon(10580)$, $ \Upsilon(10865)$, $\Upsilon(11019)$, and predict partial widths of the two-photon decays $\eta_{b0}\to\ggam$, $\chi_{b0}\to\ggam$, $\chi_{b2}\to\ggam$ for the radial excitation states below $B\bar B$ threshold ($n\le 3$). |
hep-ph/0411100 | Kalmykov Mikhail | M.Yu.Kalmykov (Dubna, JINR) and A.Sheplyakov (Dubna, JINR) | LSJK - a C++ library for arbitrary-precision numeric evaluation of the
generalized log-sine functions | 16 pages,LaTeX; to be published in Comp.Phys.Comm. v.2: typos in
Eq.(3.1) corrected; new section(3.3) added with detailed description of the
installation instructions | Comput.Phys.Commun. 172 (2005) 45-59 | 10.1016/j.cpc.2005.04.013 | null | hep-ph cs.MS cs.NA math-ph math.MP math.NA | null | Generalized log-sine functions appear in higher order epsilon-expansion of
different Feynman diagrams. We present an algorithm for numerical evaluation of
these functions of real argument. This algorithm is implemented as C++ library
with arbitrary-precision arithmetics for integer 0 < k < 9 and j > 1. Some new
relations and representations for the generalized log-sine functions are given.
| [
{
"created": "Sun, 7 Nov 2004 17:13:45 GMT",
"version": "v1"
},
{
"created": "Sun, 24 Apr 2005 23:56:43 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Kalmykov",
"M. Yu.",
"",
"Dubna, JINR"
],
[
"Sheplyakov",
"A.",
"",
"Dubna, JINR"
]
] | Generalized log-sine functions appear in higher order epsilon-expansion of different Feynman diagrams. We present an algorithm for numerical evaluation of these functions of real argument. This algorithm is implemented as C++ library with arbitrary-precision arithmetics for integer 0 < k < 9 and j > 1. Some new relations and representations for the generalized log-sine functions are given. |
hep-ph/0008067 | John Gracey | J.F. Bennett and J.A. Gracey | On the n -> 0 limit of gamma_gg(a) in QCD | 7 latex pages | Phys.Lett.B488:269-273,2000 | 10.1016/S0370-2693(00)00879-0 | LTH 483 | hep-ph | null | We consider the n -> 0 limit of the DGLAP splitting function gamma_gg(a) at
all orders in the strong coupling constant, a, by analysing the leading order
large N_f form of the associated d-dimensional critical exponent. We show that
for unpolarized scattering the pole at n = 0 which appears in successive orders
in perturbation theory is absent in the resummed expression.
| [
{
"created": "Tue, 8 Aug 2000 09:45:30 GMT",
"version": "v1"
}
] | 2010-03-25 | [
[
"Bennett",
"J. F.",
""
],
[
"Gracey",
"J. A.",
""
]
] | We consider the n -> 0 limit of the DGLAP splitting function gamma_gg(a) at all orders in the strong coupling constant, a, by analysing the leading order large N_f form of the associated d-dimensional critical exponent. We show that for unpolarized scattering the pole at n = 0 which appears in successive orders in perturbation theory is absent in the resummed expression. |
1904.05699 | Mio Kubota | Ryusuke Jinno, Mio Kubota, Kin-ya Oda, and Seong Chan Park | Higgs inflation in metric and Palatini formalisms: Required suppression
of higher dimensional operators | 29 pages, 10 figures; minor typo correction; references added | JCAP 03 (2020) 063 | 10.1088/1475-7516/2020/03/063 | DESY 19-058, CTPU-PTC-19-10, OCHA-PP-354, OU-HET-1005, LDU2019-03 | hep-ph astro-ph.CO hep-th | http://creativecommons.org/licenses/by/4.0/ | We investigate the sensitivity of Higgs(-like) inflation to higher
dimensional operators in the nonminimal couplings and in the potential, both in
the metric and Palatini formalisms. We find that, while inflationary
predictions are relatively stable against the higher dimensional operators
around the attractor point in the metric formalism, they are extremely
sensitive in the Palatini one: for the latter, inflationary predictions are
spoiled by $|\xi_4| \gtrsim 10^{-6}$ in the nonminimal couplings $(\xi_2 \phi^2
+ \xi_4 \phi^4 + \cdots)R$, or by $|\lambda_6| \gtrsim 10^{-16}$ in the
Jordan-frame potential $\lambda_4 \phi^4 + \lambda_6 \phi^6 + \cdots$ (both in
Planck units). This extreme sensitivity results from the absence of attractor
in the Palatini formalism. Our study underscores the challenge of realizing
inflationary models with the nonminimal coupling in the Palatini formalism.
| [
{
"created": "Thu, 11 Apr 2019 14:00:41 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Apr 2019 09:22:07 GMT",
"version": "v2"
},
{
"created": "Wed, 1 Apr 2020 09:46:22 GMT",
"version": "v3"
}
] | 2020-04-03 | [
[
"Jinno",
"Ryusuke",
""
],
[
"Kubota",
"Mio",
""
],
[
"Oda",
"Kin-ya",
""
],
[
"Park",
"Seong Chan",
""
]
] | We investigate the sensitivity of Higgs(-like) inflation to higher dimensional operators in the nonminimal couplings and in the potential, both in the metric and Palatini formalisms. We find that, while inflationary predictions are relatively stable against the higher dimensional operators around the attractor point in the metric formalism, they are extremely sensitive in the Palatini one: for the latter, inflationary predictions are spoiled by $|\xi_4| \gtrsim 10^{-6}$ in the nonminimal couplings $(\xi_2 \phi^2 + \xi_4 \phi^4 + \cdots)R$, or by $|\lambda_6| \gtrsim 10^{-16}$ in the Jordan-frame potential $\lambda_4 \phi^4 + \lambda_6 \phi^6 + \cdots$ (both in Planck units). This extreme sensitivity results from the absence of attractor in the Palatini formalism. Our study underscores the challenge of realizing inflationary models with the nonminimal coupling in the Palatini formalism. |
hep-ph/9706350 | David Blaschke | M.K. Volkov, E.A. Kuraev, D. Blaschke, G. Roepke, S. Schmidt | Excess low energy photon pairs from pion annihilation at the chiral
phase transition | 15 pages, LaTeX, 6 figures, Phys. Lett. B | Phys.Lett. B424 (1998) 235-243 | 10.1016/S0370-2693(98)00227-5 | null | hep-ph | null | The photon pair production by pion annihilation in a hot and dense medium at
the chiral phase transition is investigated within a chiral quark model. As a
direct consequence of this transition the $\sigma$ meson appears as a bound
state in the domain of temperatures and chemical potentials where the condition
$M_\sigma(T,\mu) \approx 2 M_\pi(T,\mu)$ is fulfilled. This effect results in a
strong enhancement of the cross section for the pion annihilation process $2
\pi \to 2 \gamma$ compared with the vacuum case. The calculation of the photon
pair production rate as function of the invariant mass shows a strong
enhancement and narrowing of the $\sigma$ meson resonance at threshold due to
chiral symmetry restoration.
| [
{
"created": "Fri, 13 Jun 1997 08:47:09 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Dec 1997 21:47:42 GMT",
"version": "v2"
},
{
"created": "Thu, 5 Feb 1998 00:04:34 GMT",
"version": "v3"
}
] | 2009-10-30 | [
[
"Volkov",
"M. K.",
""
],
[
"Kuraev",
"E. A.",
""
],
[
"Blaschke",
"D.",
""
],
[
"Roepke",
"G.",
""
],
[
"Schmidt",
"S.",
""
]
] | The photon pair production by pion annihilation in a hot and dense medium at the chiral phase transition is investigated within a chiral quark model. As a direct consequence of this transition the $\sigma$ meson appears as a bound state in the domain of temperatures and chemical potentials where the condition $M_\sigma(T,\mu) \approx 2 M_\pi(T,\mu)$ is fulfilled. This effect results in a strong enhancement of the cross section for the pion annihilation process $2 \pi \to 2 \gamma$ compared with the vacuum case. The calculation of the photon pair production rate as function of the invariant mass shows a strong enhancement and narrowing of the $\sigma$ meson resonance at threshold due to chiral symmetry restoration. |
hep-ph/9512236 | Beata Ziaja | B. Ziaja | Intermittency for coherent and incoherent current ensemble model | 13 pages, latex, no figures | Z.Phys. C71 (1996) 639-644 | 10.1007/BF02907025 | Ms. 992 (to be published in Zeitschrift fuer Physik C) | hep-ph | null | We investigate the origin of intermittency for multiparticle distribution in
momentum space, following the idea that there is a kind of power law
distribution of the space-time region of hadron emission. Using the formalism
of current ensamble model to describe boson sources we discuss intermittency
exponents for the coherent and incoherent ( chaotic) particle production
scheme.
| [
{
"created": "Tue, 5 Dec 1995 16:30:19 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Ziaja",
"B.",
""
]
] | We investigate the origin of intermittency for multiparticle distribution in momentum space, following the idea that there is a kind of power law distribution of the space-time region of hadron emission. Using the formalism of current ensamble model to describe boson sources we discuss intermittency exponents for the coherent and incoherent ( chaotic) particle production scheme. |
2005.08102 | David d'Enterria | David d'Enterria and Hua-Sheng Shao | Rare two-body decays of the top quark into a bottom meson plus an up or
charm quark | 26 pages, 5 figures | null | 10.1007/JHEP07(2020)127 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Rare two-body decays of the top quark into a neutral bottom-quark meson plus
an up- or charm-quark: $t\to {\overline B}^0+ u, c$; $t\to {\overline B}^0_{s}+
c,u$; and $t \to \Upsilon(nS)+ c,u$, are studied for the first time. The
corresponding partials widths are computed at leading order in the
non-relativistic QCD framework. The sums of all two-body branching ratios
amount to $\mathcal{B}(t \to {\overline B}^0+ {\rm jet}) \approx \mathcal{B}(t
\to {\overline B}^0_{s}+ {\rm jet}) \approx 4.2\cdot 10^{-5}$ and
$\mathcal{B}(t \to \Upsilon(nS)+ {\rm jet}) \approx 2\cdot 10^{-9}$,
respectively. The feasibility to observe the $t\to {\overline B}^0_{(s)}+{\rm
jet}$ decay is estimated in top-pair events produced in proton-proton
collisions at $\sqrt{s} = 14, 100$ TeV at the LHC and FCC, respectively.
Combining many exclusive hadronic ${\overline B}^0_{(s)}$ decays, with $J/\psi$
or $D^{0,\pm}$ final states, about 50 (16000) events are expected in 3 (20)
ab$^{-1}$ of integrated luminosity at the LHC (FCC), after typical selection
criteria, acceptance, and efficiency losses. An observation of the two-body
top-quark decay can also be achieved in the interesting $t\to
b(\rm{jet})+c(\rm{jet})$ dijet final state, where the ${\overline B}^0_{(s)}$
decay products are reconstructed as a jet, with 5300 and 1.4 million signal
events above backgrounds expected after selection criteria at the LHC and FCC,
respectively. Such unique final states provide a new direct method to precisely
measure the top-quark mass via simple 2-body invariant mass analyses.
| [
{
"created": "Sat, 16 May 2020 21:09:14 GMT",
"version": "v1"
}
] | 2020-08-26 | [
[
"d'Enterria",
"David",
""
],
[
"Shao",
"Hua-Sheng",
""
]
] | Rare two-body decays of the top quark into a neutral bottom-quark meson plus an up- or charm-quark: $t\to {\overline B}^0+ u, c$; $t\to {\overline B}^0_{s}+ c,u$; and $t \to \Upsilon(nS)+ c,u$, are studied for the first time. The corresponding partials widths are computed at leading order in the non-relativistic QCD framework. The sums of all two-body branching ratios amount to $\mathcal{B}(t \to {\overline B}^0+ {\rm jet}) \approx \mathcal{B}(t \to {\overline B}^0_{s}+ {\rm jet}) \approx 4.2\cdot 10^{-5}$ and $\mathcal{B}(t \to \Upsilon(nS)+ {\rm jet}) \approx 2\cdot 10^{-9}$, respectively. The feasibility to observe the $t\to {\overline B}^0_{(s)}+{\rm jet}$ decay is estimated in top-pair events produced in proton-proton collisions at $\sqrt{s} = 14, 100$ TeV at the LHC and FCC, respectively. Combining many exclusive hadronic ${\overline B}^0_{(s)}$ decays, with $J/\psi$ or $D^{0,\pm}$ final states, about 50 (16000) events are expected in 3 (20) ab$^{-1}$ of integrated luminosity at the LHC (FCC), after typical selection criteria, acceptance, and efficiency losses. An observation of the two-body top-quark decay can also be achieved in the interesting $t\to b(\rm{jet})+c(\rm{jet})$ dijet final state, where the ${\overline B}^0_{(s)}$ decay products are reconstructed as a jet, with 5300 and 1.4 million signal events above backgrounds expected after selection criteria at the LHC and FCC, respectively. Such unique final states provide a new direct method to precisely measure the top-quark mass via simple 2-body invariant mass analyses. |
2203.11831 | Alexander M Milov | Iakov Aizenberg (1), Zvi Citron (2) and Alexander Milov (1) ((1)
Department of Physics and Astrophysics, Weizmann Institute of Science,
Rehovot, Israel (2) Department of Physics, Ben Gurion University of the
Negev, Beer Sheva, Israel) | Can Transverse Mass Scaling Shed Light on the Event-Activity Dependence
of $\Upsilon$ Mesons Production at LHC? | 7 pages, 3 figures | null | 10.1103/PhysRevD.107.014012 | null | hep-ph nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Measurements by the CMS experiment [CMS Collaboration, JHEP04 (2014) 103; CMS
Collaboration, JHEP11 (2020) 001] reveal a deficit of charged particle tracks
in events with higher $\Upsilon$(nS) states. This observation is suggested to
be a manifestation of the excited bottomonia suppression in $pp$ interactions.
Transverse mass ($m_{\mathrm{T}}$) scaling can be implied to check this
assumption in an independent way. The scaling has been observed for a wide
range of particle species in proton-proton collisions at various energies from
the SPS to RHIC and the LHC. The observed scaling is known to be different for
baryons and mesons, and this work presents a comprehensive study of the
$m_{\mathrm{T}}$-scaling of mesons at LHC energies with a focus on heavier
mesons. The study demonstrates patterns in the scaling properties of mesons,
which are related to the particle quark content. In particular, light species
and ground-state quarkonia obey the same scaling, whereas open-flavor particles
deviate from it because their spectra are significantly harder. The magnitude
of deviation depends on the flavor of the heaviest quark in the meson. By
extending the $m_{\mathrm{T}}$-scaling assumption to the excited bottomonia
states, it is observed that the measured cross sections of $\Upsilon$(2S) and
$\Upsilon$(3S) are reduced by factors of 1.6 and 2.4 compared to the
expectation from the scaling. This observation is consistent with recently
observed differences between the event-activity dependence of different
$\Upsilon$(nS) meson states.
| [
{
"created": "Tue, 22 Mar 2022 15:58:34 GMT",
"version": "v1"
},
{
"created": "Mon, 9 May 2022 11:29:57 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Jan 2023 16:42:52 GMT",
"version": "v3"
}
] | 2023-01-25 | [
[
"Aizenberg",
"Iakov",
""
],
[
"Citron",
"Zvi",
""
],
[
"Milov",
"Alexander",
""
]
] | Measurements by the CMS experiment [CMS Collaboration, JHEP04 (2014) 103; CMS Collaboration, JHEP11 (2020) 001] reveal a deficit of charged particle tracks in events with higher $\Upsilon$(nS) states. This observation is suggested to be a manifestation of the excited bottomonia suppression in $pp$ interactions. Transverse mass ($m_{\mathrm{T}}$) scaling can be implied to check this assumption in an independent way. The scaling has been observed for a wide range of particle species in proton-proton collisions at various energies from the SPS to RHIC and the LHC. The observed scaling is known to be different for baryons and mesons, and this work presents a comprehensive study of the $m_{\mathrm{T}}$-scaling of mesons at LHC energies with a focus on heavier mesons. The study demonstrates patterns in the scaling properties of mesons, which are related to the particle quark content. In particular, light species and ground-state quarkonia obey the same scaling, whereas open-flavor particles deviate from it because their spectra are significantly harder. The magnitude of deviation depends on the flavor of the heaviest quark in the meson. By extending the $m_{\mathrm{T}}$-scaling assumption to the excited bottomonia states, it is observed that the measured cross sections of $\Upsilon$(2S) and $\Upsilon$(3S) are reduced by factors of 1.6 and 2.4 compared to the expectation from the scaling. This observation is consistent with recently observed differences between the event-activity dependence of different $\Upsilon$(nS) meson states. |
2402.01234 | Robert Vertesi | R\'obert V\'ertesi and Zolt\'an Varga | Connection of event shapes to the heavy-flavor baryon enhancement | Proceedings of the ISMD 2023 Conference | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent results from ALICE and CMS show a low-transverse-momentum enhancement
of charm baryon-to-meson production ratios over model predictions based on
$e^+e^-$ collisions. This new development challenges the universality of
fragmentation. We studied the charm-baryon enhancement in collision events
generated by PYTHIA 8 and applied a color-reconnection model beyond leading
color approximation. We proposed a measurement method based on several
event-activity classifiers, to identify the origin of the charm-baryon
enhancement. In this work we extend our studies to a new event classifier,
flattenicity, that considers a broad pseudorapidity range. We have also studied
the role of isospin and strangeness by comparing the production of different
charmed baryons. The observables we explored provide a unique opportunity in
the upcoming measurements from the high-luminosity LHC Run 3 period to better
understand heavy-flavor fragmentation mechanisms, and will help the further
development of models.
| [
{
"created": "Fri, 2 Feb 2024 08:56:52 GMT",
"version": "v1"
}
] | 2024-02-05 | [
[
"Vértesi",
"Róbert",
""
],
[
"Varga",
"Zoltán",
""
]
] | Recent results from ALICE and CMS show a low-transverse-momentum enhancement of charm baryon-to-meson production ratios over model predictions based on $e^+e^-$ collisions. This new development challenges the universality of fragmentation. We studied the charm-baryon enhancement in collision events generated by PYTHIA 8 and applied a color-reconnection model beyond leading color approximation. We proposed a measurement method based on several event-activity classifiers, to identify the origin of the charm-baryon enhancement. In this work we extend our studies to a new event classifier, flattenicity, that considers a broad pseudorapidity range. We have also studied the role of isospin and strangeness by comparing the production of different charmed baryons. The observables we explored provide a unique opportunity in the upcoming measurements from the high-luminosity LHC Run 3 period to better understand heavy-flavor fragmentation mechanisms, and will help the further development of models. |
1101.2610 | Christoph Weniger | Gilles Vertongen and Christoph Weniger | Hunting Dark Matter Gamma-Ray Lines with the Fermi LAT | 31 pages, 10 figures, 3 tables; revised version with figures and
discussions added | null | 10.1088/1475-7516/2011/05/027 | DESY 10-237, MPP-2010-166 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Monochromatic photons could be produced in the annihilation or decay of dark
matter particles. At high energies, the search for such line features in the
cosmic gamma-ray spectrum is essentially background free because plausible
astrophysical processes are not expected to produce such a signal. The
observation of a gamma-ray line would hence be a `smoking-gun' signature for
dark matter, making the search for such signals particularly attractive. Among
the different dark matter models predicting gamma-ray lines, the local
supersymmetric extension of the standard model with small R-parity violation
and gravitino LSP is of particular interest because it provides a framework
where primordial nucleosynthesis, gravitino dark matter and thermal
leptogenesis are naturally consistent. Using the two-years Fermi LAT data, we
present a dedicated search for gamma-ray lines coming from dark matter
annihilation or decay in the Galactic halo. Taking into account the full
detector response, and using a binned profile likelihood method, we search for
significant line features in the energy spectrum of the diffuse flux observed
in different regions of the sky. No evidence for a line signal at the 5-sigma
level is found for photon energies between 1 and 300 GeV, and conservative
bounds on dark matter decay rates and annihilation cross sections are
presented. Implications for gravitino dark matter in presence of small R-parity
violation are discussed, as well as the impact of our results on the prospect
for seeing long-lived neutralinos or staus at the LHC.
| [
{
"created": "Thu, 13 Jan 2011 17:10:26 GMT",
"version": "v1"
},
{
"created": "Fri, 6 May 2011 15:51:06 GMT",
"version": "v2"
}
] | 2015-05-27 | [
[
"Vertongen",
"Gilles",
""
],
[
"Weniger",
"Christoph",
""
]
] | Monochromatic photons could be produced in the annihilation or decay of dark matter particles. At high energies, the search for such line features in the cosmic gamma-ray spectrum is essentially background free because plausible astrophysical processes are not expected to produce such a signal. The observation of a gamma-ray line would hence be a `smoking-gun' signature for dark matter, making the search for such signals particularly attractive. Among the different dark matter models predicting gamma-ray lines, the local supersymmetric extension of the standard model with small R-parity violation and gravitino LSP is of particular interest because it provides a framework where primordial nucleosynthesis, gravitino dark matter and thermal leptogenesis are naturally consistent. Using the two-years Fermi LAT data, we present a dedicated search for gamma-ray lines coming from dark matter annihilation or decay in the Galactic halo. Taking into account the full detector response, and using a binned profile likelihood method, we search for significant line features in the energy spectrum of the diffuse flux observed in different regions of the sky. No evidence for a line signal at the 5-sigma level is found for photon energies between 1 and 300 GeV, and conservative bounds on dark matter decay rates and annihilation cross sections are presented. Implications for gravitino dark matter in presence of small R-parity violation are discussed, as well as the impact of our results on the prospect for seeing long-lived neutralinos or staus at the LHC. |
2202.07352 | Sebastian Bieringer | Sebastian Bieringer, Anja Butter, Sascha Diefenbacher, Engin Eren,
Frank Gaede, Daniel Hundhausen, Gregor Kasieczka, Benjamin Nachman, Tilman
Plehn and Mathias Trabs | Calomplification -- The Power of Generative Calorimeter Models | 17 pages, 10 figures | JINST 17 P09028 (2022) | 10.1088/1748-0221/17/09/P09028 | DESY-22-031 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the high computational costs of classical simulations,
machine-learned generative models can be extremely useful in particle physics
and elsewhere. They become especially attractive when surrogate models can
efficiently learn the underlying distribution, such that a generated sample
outperforms a training sample of limited size. This kind of GANplification has
been observed for simple Gaussian models. We show the same effect for a physics
simulation, specifically photon showers in an electromagnetic calorimeter.
| [
{
"created": "Tue, 15 Feb 2022 12:19:54 GMT",
"version": "v1"
},
{
"created": "Mon, 9 May 2022 12:18:53 GMT",
"version": "v2"
},
{
"created": "Wed, 25 Jan 2023 16:26:57 GMT",
"version": "v3"
}
] | 2023-01-26 | [
[
"Bieringer",
"Sebastian",
""
],
[
"Butter",
"Anja",
""
],
[
"Diefenbacher",
"Sascha",
""
],
[
"Eren",
"Engin",
""
],
[
"Gaede",
"Frank",
""
],
[
"Hundhausen",
"Daniel",
""
],
[
"Kasieczka",
"Gregor",
""
]... | Motivated by the high computational costs of classical simulations, machine-learned generative models can be extremely useful in particle physics and elsewhere. They become especially attractive when surrogate models can efficiently learn the underlying distribution, such that a generated sample outperforms a training sample of limited size. This kind of GANplification has been observed for simple Gaussian models. We show the same effect for a physics simulation, specifically photon showers in an electromagnetic calorimeter. |
1410.0221 | Yongchao Zhang | Demos Kazanas, Rabindra N. Mohapatra, Shmuel Nussinov, Vigdor L.
Teplitz, Yongchao Zhang | Supernova Bounds on the Dark Photon Using its Electromagnetic Decay | 10 pages, 6 figures, minor typos corrected, version to appear in NPB | Nuclear Physics B 890 (2015) 17 | 10.1016/j.nuclphysb.2014.11.009 | UMD-PP- 014-015 | hep-ph astro-ph.CO astro-ph.HE astro-ph.SR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The hypothetical massive dark photon ($\gamma'$) which has kinetic mixing
with the SM photon can decay electromagnetically to $e^+e^-$ pairs if its mass
$m$ exceeds $2m_e$ and otherwise into three SM photons. These decays yield
cosmological and supernovae associated signatures. We briefly discuss these
signatures, particularly in connection with the supernova SN1987A and delineate
the extra constraints that may then arise on the mass and mixing parameter of
the dark photon. In particular, we find that for dark photon mass $m_{\gamma'}$
in the 5-20 MeV range, arguments based on supernova 1987A observations lead to
a bound on $\epsilon$ which is about 300 times stronger than the presently
existing bounds based on energy loss arguments.
| [
{
"created": "Wed, 1 Oct 2014 13:45:46 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Nov 2014 07:22:25 GMT",
"version": "v2"
},
{
"created": "Fri, 7 Nov 2014 18:44:19 GMT",
"version": "v3"
}
] | 2014-11-21 | [
[
"Kazanas",
"Demos",
""
],
[
"Mohapatra",
"Rabindra N.",
""
],
[
"Nussinov",
"Shmuel",
""
],
[
"Teplitz",
"Vigdor L.",
""
],
[
"Zhang",
"Yongchao",
""
]
] | The hypothetical massive dark photon ($\gamma'$) which has kinetic mixing with the SM photon can decay electromagnetically to $e^+e^-$ pairs if its mass $m$ exceeds $2m_e$ and otherwise into three SM photons. These decays yield cosmological and supernovae associated signatures. We briefly discuss these signatures, particularly in connection with the supernova SN1987A and delineate the extra constraints that may then arise on the mass and mixing parameter of the dark photon. In particular, we find that for dark photon mass $m_{\gamma'}$ in the 5-20 MeV range, arguments based on supernova 1987A observations lead to a bound on $\epsilon$ which is about 300 times stronger than the presently existing bounds based on energy loss arguments. |
hep-ph/0209332 | Vincenzo Cirigliano | V. Cirigliano, J.F. Donoghue, E. Golowich, K. Maltman | K -> pi pi Electroweak Penguins in the Chiral Limit | 4 pages, 2 figures. Contribution to QCD02, International Conference
on Quantum Chromo-Dynamics, Montpellier (France), July 2-9 2002 | null | 10.1016/S0920-5632(03)01846-2 | IFIC/02-45, FTUV/02-0927 | hep-ph | null | We report on dispersive and finite energy sum rule analyses of the
electroweak penguin matrix elements < (pi pi) | Q_{7,8} | K > in the chiral
limit. We accomplish the correct perturbative matching (scale and scheme
dependence) at NLO in alpha_s, and we describe two different strategies for
numerical evaluation.
| [
{
"created": "Fri, 27 Sep 2002 11:07:43 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Cirigliano",
"V.",
""
],
[
"Donoghue",
"J. F.",
""
],
[
"Golowich",
"E.",
""
],
[
"Maltman",
"K.",
""
]
] | We report on dispersive and finite energy sum rule analyses of the electroweak penguin matrix elements < (pi pi) | Q_{7,8} | K > in the chiral limit. We accomplish the correct perturbative matching (scale and scheme dependence) at NLO in alpha_s, and we describe two different strategies for numerical evaluation. |
1201.5906 | Scott A. Yost | Scott Yost, Valerie Halyo, Miroslav Hejna, B.F.L. Ward | HERWIRI2: CEEX Electroweak Corrections in a Hadronic MC | Presented by Scott Yost at the 10th International Symposium on
Radiative Corrections, RADCOR2011, Sept. 26-30, 2011, Mamallapuram, India. 8
pages | null | null | BU-HEPP-11-06 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Reaching the 1% precision level for W and Z production calculations for the
LHC will require a mixture of higher order QCD and electroweak corrections. As
a first step toward implementing the combined QED\otimesQCD exponentiation
proposed in previous work, we have implemented the order alpha electroweak
corrections and YFS exponentiation structure of the KK Monte Carlo in HERWIG.
We discuss the current status of this program and sketch the further
developments needed to reach the desired precision level.
| [
{
"created": "Fri, 27 Jan 2012 22:47:14 GMT",
"version": "v1"
}
] | 2012-01-31 | [
[
"Yost",
"Scott",
""
],
[
"Halyo",
"Valerie",
""
],
[
"Hejna",
"Miroslav",
""
],
[
"Ward",
"B. F. L.",
""
]
] | Reaching the 1% precision level for W and Z production calculations for the LHC will require a mixture of higher order QCD and electroweak corrections. As a first step toward implementing the combined QED\otimesQCD exponentiation proposed in previous work, we have implemented the order alpha electroweak corrections and YFS exponentiation structure of the KK Monte Carlo in HERWIG. We discuss the current status of this program and sketch the further developments needed to reach the desired precision level. |
1405.0418 | Michael Lublinsky | Alex Kovner, Michael Lublinsky, and Yair Mulian | NLO JIMWLK evolution unabridged | 39 pages | null | 10.1007/JHEP08(2014)114 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In Ref. [1] we presented the JIMWLK Hamiltonian for high energy evolution of
QCD amplitudes at the next-to-leading order accuracy in $\alpha_s$. In the
present paper we provide details of our original derivation, which was not
reported in [1], and provide the Hamiltonian in the form appropriate for action
on color singlet as well as color nonsinglet states. The rapidity evolution of
the quark dipole generated by this Hamiltonian is computed and compared with
the corresponding result of Balitsky and Chirilli [2]. We then establish the
equivalence between the NLO JIMWLK Hamiltonian and the NLO version of the
Balitsky's hierarchy [3], which includes action on nonsinglet combinations of
Wilson lines. Finally, we present complete evolution equation for three-quark
Wilson loop operator, thus extending the results of Grabovsky [4].
| [
{
"created": "Fri, 2 May 2014 14:38:33 GMT",
"version": "v1"
},
{
"created": "Tue, 6 May 2014 15:39:41 GMT",
"version": "v2"
}
] | 2015-06-19 | [
[
"Kovner",
"Alex",
""
],
[
"Lublinsky",
"Michael",
""
],
[
"Mulian",
"Yair",
""
]
] | In Ref. [1] we presented the JIMWLK Hamiltonian for high energy evolution of QCD amplitudes at the next-to-leading order accuracy in $\alpha_s$. In the present paper we provide details of our original derivation, which was not reported in [1], and provide the Hamiltonian in the form appropriate for action on color singlet as well as color nonsinglet states. The rapidity evolution of the quark dipole generated by this Hamiltonian is computed and compared with the corresponding result of Balitsky and Chirilli [2]. We then establish the equivalence between the NLO JIMWLK Hamiltonian and the NLO version of the Balitsky's hierarchy [3], which includes action on nonsinglet combinations of Wilson lines. Finally, we present complete evolution equation for three-quark Wilson loop operator, thus extending the results of Grabovsky [4]. |
1812.02344 | Cyrus Faroughy | Cyrus Faroughy | Cosmological Perturbations in a Universe with a Domain Wall Era | Ph.D. Thesis, Dec 2017 | null | null | null | hep-ph gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Topologically protected sheet-like surfaces, called domain walls, form when
the potential of a field has a discrete symmetry that is spontaneously broken.
Since this condition is commonplace in field theory, it is plausible that many
of these walls were produced at some point in the early universe. Moreover, for
potentials with a rich enough structure, the walls can join and form a (at
large scales) homogeneous and isotropic network that dominates the energy
density of the universe for some time before decaying. In this thesis, we study
the faith of large scale perturbations in a cosmology with a short period of
domain wall dominance. Treating the domain wall network as a relativistic
elastic solid at large scales, we show that the perturbations that exited the
horizon during inflation get suppressed during the domain wall era, before
re-entering the horizon. This power suppression occurs because, unlike a
fluid-like universe, a solid-like universe can support sizable anisotropic
stress gradients across large scales which effectively act as mass for the
scalar and tensor modes. Interestingly, the amplitude of the primordial scalar
power spectrum can be closer to one in this cosmology and still give the
observed value of $10^{-9}$ today. As a result, the usual bounds on the energy
scale of inflation get relaxed to values closer to the (more natural) Planck
scale. In the last part of this thesis, as an existence proof, we present a
hybrid inflation model with $N$ `waterfall' fields that can realize the
proposed cosmology. In this model, a domain wall network forms when an
approximate $O(N)$ symmetry gets spontaneously broken at the end of inflation,
and for $N \geq 5$, we show that there is a region in parameter space where the
network dominates the energy density for a few e-folds before decaying and
reheating the universe.
| [
{
"created": "Thu, 6 Dec 2018 04:35:12 GMT",
"version": "v1"
}
] | 2018-12-07 | [
[
"Faroughy",
"Cyrus",
""
]
] | Topologically protected sheet-like surfaces, called domain walls, form when the potential of a field has a discrete symmetry that is spontaneously broken. Since this condition is commonplace in field theory, it is plausible that many of these walls were produced at some point in the early universe. Moreover, for potentials with a rich enough structure, the walls can join and form a (at large scales) homogeneous and isotropic network that dominates the energy density of the universe for some time before decaying. In this thesis, we study the faith of large scale perturbations in a cosmology with a short period of domain wall dominance. Treating the domain wall network as a relativistic elastic solid at large scales, we show that the perturbations that exited the horizon during inflation get suppressed during the domain wall era, before re-entering the horizon. This power suppression occurs because, unlike a fluid-like universe, a solid-like universe can support sizable anisotropic stress gradients across large scales which effectively act as mass for the scalar and tensor modes. Interestingly, the amplitude of the primordial scalar power spectrum can be closer to one in this cosmology and still give the observed value of $10^{-9}$ today. As a result, the usual bounds on the energy scale of inflation get relaxed to values closer to the (more natural) Planck scale. In the last part of this thesis, as an existence proof, we present a hybrid inflation model with $N$ `waterfall' fields that can realize the proposed cosmology. In this model, a domain wall network forms when an approximate $O(N)$ symmetry gets spontaneously broken at the end of inflation, and for $N \geq 5$, we show that there is a region in parameter space where the network dominates the energy density for a few e-folds before decaying and reheating the universe. |
hep-ph/0007328 | Takeo Moroi | Takeo Moroi | CP violation in B_d \to \phi K_S in SUSY GUT with right-handed neutrinos | 12 pages, 2 figures | Phys.Lett. B493 (2000) 366-374 | 10.1016/S0370-2693(00)01160-6 | TU-599, RCNS-00-01 | hep-ph | null | CP violation in the B_d system is discussed in the supersymmetric grand
unified theory (GUT) with the right-handed neutrinos. Above the GUT scale, the
right-handed down-type squarks couple to the right-handed neutrinos. Due to the
renormalization group effect, flavor violations in the lepton sector may be
transfered to the right-handed down-type squark mass matrix, which affects the
CP violation in the B decay. Taking into account this effect, we compare the CP
violation in B_d \to \psi K_S and B_d \to \phi K_S processes. We will find that
a significant difference is possible between the CP violating phases in two
decay processes.
| [
{
"created": "Fri, 28 Jul 2000 11:53:21 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Moroi",
"Takeo",
""
]
] | CP violation in the B_d system is discussed in the supersymmetric grand unified theory (GUT) with the right-handed neutrinos. Above the GUT scale, the right-handed down-type squarks couple to the right-handed neutrinos. Due to the renormalization group effect, flavor violations in the lepton sector may be transfered to the right-handed down-type squark mass matrix, which affects the CP violation in the B decay. Taking into account this effect, we compare the CP violation in B_d \to \psi K_S and B_d \to \phi K_S processes. We will find that a significant difference is possible between the CP violating phases in two decay processes. |
0708.1801 | Firooz Arash | Firooz Arash and Fatemeh Taghavi-Shahri | Polarized Structure of Nucleon in the Valon Representation | 24 pages, 9 Figures | JHEP 0707:071,2007; Erratum-ibid.1008:106,2010 | 10.1088/1126-6708/2007/07/071 10.1007/JHEP08(2010)106 | null | hep-ph | null | We have utilized the concept of valon model to calculate the spin structure
functions of proton, neutron and deuteron. The valon structure itself is
universal and arises from the perturbative dressing of the valence quark in
QCD. Our results agree rather well with all the relevant experimental data on
$g_{1}^{p, n, d}$ and $g_{A}/g_{v}$, and suggests that the sea quark
contribution to the spin of proton is consistent with zero. It also reveals
that while the total quark contribution to the spin of valon is almost constant
at $Q^{2}>=1$ the gluon contribution grows with the increase of $Q^2$ and hence
requiring a sizable negative orbital angular momentum component $L_z$. This
component along with the singlet and non-singlet parts are calculated in the
Next-to-Leading order in QCD. We speculate that gluon contribution to the spin
content of the proton is about 60% for all $Q^2$ values. Finally, we show that
the size of gluon polarization and hence, $L_{z}$, is sensitive to the initial
scale$Q_{0}^{2}$.
| [
{
"created": "Tue, 14 Aug 2007 05:11:46 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Arash",
"Firooz",
""
],
[
"Taghavi-Shahri",
"Fatemeh",
""
]
] | We have utilized the concept of valon model to calculate the spin structure functions of proton, neutron and deuteron. The valon structure itself is universal and arises from the perturbative dressing of the valence quark in QCD. Our results agree rather well with all the relevant experimental data on $g_{1}^{p, n, d}$ and $g_{A}/g_{v}$, and suggests that the sea quark contribution to the spin of proton is consistent with zero. It also reveals that while the total quark contribution to the spin of valon is almost constant at $Q^{2}>=1$ the gluon contribution grows with the increase of $Q^2$ and hence requiring a sizable negative orbital angular momentum component $L_z$. This component along with the singlet and non-singlet parts are calculated in the Next-to-Leading order in QCD. We speculate that gluon contribution to the spin content of the proton is about 60% for all $Q^2$ values. Finally, we show that the size of gluon polarization and hence, $L_{z}$, is sensitive to the initial scale$Q_{0}^{2}$. |
hep-ph/0111071 | Sun Myong Kim | Sun Myong Kim | A Test of SU(15) at HERA Using The HELAS Program | 5 pages in latex with 4 figures | Mod.Phys.Lett. A16 (2001) 2115 | 10.1142/S0217732301005448 | null | hep-ph | null | A possible SU(15) process at HERA is investigated. The process that we
consider is $e^- P\ra \bar\nu_e \mu^- \mu^- +anything$ through the exchange of
new heavy gauge bosons $X^-$ and $X^{--}$ which are predicted in SU(15). This
process produces two easily observable like-sign muons in the final state. The
cross section of this process is calculated by using HELAS and VEGAS programs,
and PDF-library functions. The cross section turns out to be small to be
observed in near future.
| [
{
"created": "Wed, 7 Nov 2001 13:08:23 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Kim",
"Sun Myong",
""
]
] | A possible SU(15) process at HERA is investigated. The process that we consider is $e^- P\ra \bar\nu_e \mu^- \mu^- +anything$ through the exchange of new heavy gauge bosons $X^-$ and $X^{--}$ which are predicted in SU(15). This process produces two easily observable like-sign muons in the final state. The cross section of this process is calculated by using HELAS and VEGAS programs, and PDF-library functions. The cross section turns out to be small to be observed in near future. |
hep-ph/9612292 | James Wells | James D. Wells (SLAC) | The electroweak symmetry breaking Higgs boson in models with top-quark
condensation | 16 pages, LaTeX | Phys.Rev. D56 (1997) 1504-1510 | 10.1103/PhysRevD.56.1504 | SLAC-PUB-7374 | hep-ph | null | The top quark may get its mass not from a fundamental scalar but a
Nambu-Jona-Lasinio mechanism involving a strongly coupled gauge sector that
triggers top-quark condensation. Forbidding a large hierarchy in the gap
equation implies that top-quark condensation is a spectator to electroweak
symmetry breaking, which must be accomplished mainly by another sector. The
properties of the electroweak symmetry breaking scalars are identified.
Production mechanisms and decay modes are studied. Unlike the standard model,
the scalar degree of freedom most relevant to electroweak symmetry breaking can
only be produced by its gauge interactions. An e-e-\mu+ + \mu-\mu-e+ signal is
proposed to help unambiguously detect the presence of such a gauge-coupled
Higgs if it is light. Other useful modes of detection are also presented, and a
summary is made of the search capabilities at LEPII, Tevatron, and LHC.
| [
{
"created": "Mon, 9 Dec 1996 00:49:26 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Dec 1996 01:14:58 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Wells",
"James D.",
"",
"SLAC"
]
] | The top quark may get its mass not from a fundamental scalar but a Nambu-Jona-Lasinio mechanism involving a strongly coupled gauge sector that triggers top-quark condensation. Forbidding a large hierarchy in the gap equation implies that top-quark condensation is a spectator to electroweak symmetry breaking, which must be accomplished mainly by another sector. The properties of the electroweak symmetry breaking scalars are identified. Production mechanisms and decay modes are studied. Unlike the standard model, the scalar degree of freedom most relevant to electroweak symmetry breaking can only be produced by its gauge interactions. An e-e-\mu+ + \mu-\mu-e+ signal is proposed to help unambiguously detect the presence of such a gauge-coupled Higgs if it is light. Other useful modes of detection are also presented, and a summary is made of the search capabilities at LEPII, Tevatron, and LHC. |
2309.02400 | H\'ector Novales-S\'anchez | H\'ector Novales-S\'anchez, M\'onica Salinas | Majorana neutrinos in the triple gauge boson coupling $ZZZ^*$ | 20 pages, 5 figures, 3 tables | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Confirmed by the measurement of neutrino oscillations, neutrino mass is
recognized as a genuine manifestation of physics beyond the Standard Model,
while its originating mechanism remains a mystery. Moreover, the proper
field-theory description of neutrinos, whether they are Majorana or Dirac type,
must be linked to such a mechanism. The present work addresses the calculation,
estimation, and analysis of one-loop contributions from virtual Majorana
neutrinos, light and heavy as well, to the neutral gauge boson coupling $ZZZ$,
which participates in $Z$-boson pair production from $e^+e^-$ collisions. This
task is carried out in the framework defined by a seesaw variant in which light
neutrinos remain massless at tree level, then becoming massive radiatively. The
$ZZZ^*$ coupling, with $Z^*$ an off-shell $Z$ boson, is defined by two form
factors, namely, $f_4$, characterizing CP-odd effects, and $f_5$, which is
CP-even. Constraints from the Large Hadron Collider on both these quantities
are currently ${\cal O}(10^{-4})$. Our calculation yields CP-nonpreserving
contributions to $ZZZ$, which are absent in the framework of the sole Standard
Model. Our estimations show that the $f_4$ contribution might be as large as
${\cal O}(10^{-7})$ for heavy-neutrino masses $\sim1\,{\rm TeV}$. CP-even
contributions $f_5$ are also generated, which are, in general, larger than
their CP-odd counterparts. We estimate them to be as large as ${\cal
O}(10^{-4})$ at a center-of-mass energy of $500\,{\rm GeV}$, in $e^+e^-$
collisions.
| [
{
"created": "Tue, 5 Sep 2023 17:22:35 GMT",
"version": "v1"
}
] | 2023-09-06 | [
[
"Novales-Sánchez",
"Héctor",
""
],
[
"Salinas",
"Mónica",
""
]
] | Confirmed by the measurement of neutrino oscillations, neutrino mass is recognized as a genuine manifestation of physics beyond the Standard Model, while its originating mechanism remains a mystery. Moreover, the proper field-theory description of neutrinos, whether they are Majorana or Dirac type, must be linked to such a mechanism. The present work addresses the calculation, estimation, and analysis of one-loop contributions from virtual Majorana neutrinos, light and heavy as well, to the neutral gauge boson coupling $ZZZ$, which participates in $Z$-boson pair production from $e^+e^-$ collisions. This task is carried out in the framework defined by a seesaw variant in which light neutrinos remain massless at tree level, then becoming massive radiatively. The $ZZZ^*$ coupling, with $Z^*$ an off-shell $Z$ boson, is defined by two form factors, namely, $f_4$, characterizing CP-odd effects, and $f_5$, which is CP-even. Constraints from the Large Hadron Collider on both these quantities are currently ${\cal O}(10^{-4})$. Our calculation yields CP-nonpreserving contributions to $ZZZ$, which are absent in the framework of the sole Standard Model. Our estimations show that the $f_4$ contribution might be as large as ${\cal O}(10^{-7})$ for heavy-neutrino masses $\sim1\,{\rm TeV}$. CP-even contributions $f_5$ are also generated, which are, in general, larger than their CP-odd counterparts. We estimate them to be as large as ${\cal O}(10^{-4})$ at a center-of-mass energy of $500\,{\rm GeV}$, in $e^+e^-$ collisions. |
hep-ph/9308265 | Tim Morris | Tim R. Morris | The Exact Renormalisation Group and Approximate Solutions | 49 pages (with figures), Plain TeX, uses psfig, 7 postscript figures
appended as uuencoded compressed tar file, SHEP 92/93-27, CERN-TH.6977/93,
Note Added with more complete comparison to earlier work | Int.J.Mod.Phys. A9 (1994) 2411-2450 | 10.1142/S0217751X94000972 | null | hep-ph hep-th | null | We investigate the structure of Polchinski's formulation of the flow
equations for the continuum Wilson effective action.
Reinterpretations in terms of I.R. cutoff greens functions are given. A
promising non-perturbative approximation scheme is derived by carefully taking
the sharp cutoff limit and expanding in `irrelevancy' of operators.
We illustrate with two simple models of four dimensional $\lambda \varphi^4$
theory: the cactus approximation, and a model incorporating the first
irrelevant correction to the renormalized coupling. The qualitative and
quantitative behaviour give confidence in a fuller use of this method for
obtaining accurate results.
| [
{
"created": "Thu, 12 Aug 1993 15:41:20 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Aug 1993 16:26:20 GMT",
"version": "v2"
},
{
"created": "Fri, 8 Oct 1993 10:16:31 GMT",
"version": "v3"
}
] | 2009-10-22 | [
[
"Morris",
"Tim R.",
""
]
] | We investigate the structure of Polchinski's formulation of the flow equations for the continuum Wilson effective action. Reinterpretations in terms of I.R. cutoff greens functions are given. A promising non-perturbative approximation scheme is derived by carefully taking the sharp cutoff limit and expanding in `irrelevancy' of operators. We illustrate with two simple models of four dimensional $\lambda \varphi^4$ theory: the cactus approximation, and a model incorporating the first irrelevant correction to the renormalized coupling. The qualitative and quantitative behaviour give confidence in a fuller use of this method for obtaining accurate results. |
1309.5890 | Don Colladay | Don Colladay | Covariant Photon Quantization in the SME | Presented at the Sixth Meeting on CPT and Lorentz Symmetry,
Bloomington, Indiana, June 17-21, 2013 | null | 10.1142/9789814566438_0032 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Gupta Bleuler quantization procedure is applied to the SME photon sector.
A direct application of the method to the massless case fails due to an
unavoidable incompleteness in the polarization states. A mass term can be
included into the photon lagrangian to rescue the quantization procedure and
maintain covariance.
| [
{
"created": "Mon, 23 Sep 2013 17:36:36 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Colladay",
"Don",
""
]
] | The Gupta Bleuler quantization procedure is applied to the SME photon sector. A direct application of the method to the massless case fails due to an unavoidable incompleteness in the polarization states. A mass term can be included into the photon lagrangian to rescue the quantization procedure and maintain covariance. |
0711.3596 | Roberto Pittau | Giovanni Ossola, Costas G. Papadopoulos, Roberto Pittau | CutTools: a program implementing the OPP reduction method to compute
one-loop amplitudes | Version published in JHEP | JHEP 0803:042,2008 | 10.1088/1126-6708/2008/03/042 | null | hep-ph | null | We present a program that implements the OPP reduction method to extract the
coefficients of the one-loop scalar integrals from a user defined
(sub)-amplitude or Feynman Diagram, as well as the rational terms coming from
the 4-dimensional part of the numerator. The rational pieces coming from the
epsilon-dimensional part of the numerator are treated as an external input, and
can be computed with the help of dedicated tree-level like Feynman rules.
Possible numerical instabilities are dealt with the help of arbitrary
precision routines, that activate only when needed.
| [
{
"created": "Thu, 22 Nov 2007 15:24:20 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Apr 2008 15:40:28 GMT",
"version": "v2"
}
] | 2011-05-05 | [
[
"Ossola",
"Giovanni",
""
],
[
"Papadopoulos",
"Costas G.",
""
],
[
"Pittau",
"Roberto",
""
]
] | We present a program that implements the OPP reduction method to extract the coefficients of the one-loop scalar integrals from a user defined (sub)-amplitude or Feynman Diagram, as well as the rational terms coming from the 4-dimensional part of the numerator. The rational pieces coming from the epsilon-dimensional part of the numerator are treated as an external input, and can be computed with the help of dedicated tree-level like Feynman rules. Possible numerical instabilities are dealt with the help of arbitrary precision routines, that activate only when needed. |
hep-ph/0511031 | Kazunori Itakura | K. Itakura | Recent results on saturation and CGC | 10 pages, 4 figures. Plenary talk given at 18th International
Conference on Ultrarelativistic Nucleus-Nucleus Collisions: Quark Matter
2005, Budapest, Hungary, 4-9 Aug 2002 | Nucl.Phys. A774 (2006) 277-286 | 10.1016/j.nuclphysa.2006.06.048 | null | hep-ph | null | I discuss recent results on the Color Glass Condensate which is a dense
saturated gluonic state and appears as the universal picture of hadrons or
nuclei at very high energies.
| [
{
"created": "Thu, 3 Nov 2005 18:03:21 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Itakura",
"K.",
""
]
] | I discuss recent results on the Color Glass Condensate which is a dense saturated gluonic state and appears as the universal picture of hadrons or nuclei at very high energies. |
1907.06308 | Luis Anchordoqui | L. A. Anchordoqui, I. Antoniadis, V. Barger, F. Cornet, C. Garc\'ia
Canal, M. Guti\'errez, J. I. Illana, J. G. Learned, D. Marfatia, M. Masip, S.
Pakvasa, S. Palomares-Ruiz, J. F. Soriano, T. J. Weiler | The pros and cons of beyond standard model interpretations of ANITA
events | To appear in Proceedings of the 36th International Cosmic Ray
Conference | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Antarctic Impulsive Transient Antenna (ANITA) experiment has observed two
air shower events with energy $\sim 500~{\rm PeV}$ emerging from the Earth with
exit angles $\sim 30^\circ$ above the horizon. As was immediately noted by the
ANITA Collaboration, these events (in principle) could originate in the
atmospheric decay of an upgoing $\tau$-lepton produced through a charged
current interaction of a $\nu_\tau$ inside the Earth. However, the relatively
steep arrival angles of these perplexing events create tension with the
standard model (SM) neutrino-nucleon interaction cross section. Deepening the
conundrum, the IceCube neutrino telescope and the Pierre Auger Observatory with
substantially larger exposures to cosmic $\nu_\tau$'s in this energy range have
not observed any events. This lack of observation implies that the messenger
particle (MP) giving rise to ANITA events must produce an air shower event rate
at least a factor of 40 larger than that produced by a flux of $\tau$-neutrinos
to avoid conflicts with the upper limits reported by the IceCube and the Pierre
Auger collaborations. In addition, the sensitivity of ANITA to MP-induced
events must be comparable to or larger than those of IceCube and Auger to avoid
conflict with the non-observation of any signal at these facilities. Beyond SM
interpretations of ANITA events can be classified according to whether the MPs:
(i) live inside the Earth, (ii) originate in neutrino-nucleon collisions inside
the Earth, (iii) come from cosmological distances. In this communication we
investigate the positive and negative facets of these three classes of models.
| [
{
"created": "Mon, 15 Jul 2019 01:43:30 GMT",
"version": "v1"
},
{
"created": "Fri, 2 Aug 2019 12:40:40 GMT",
"version": "v2"
}
] | 2019-08-05 | [
[
"Anchordoqui",
"L. A.",
""
],
[
"Antoniadis",
"I.",
""
],
[
"Barger",
"V.",
""
],
[
"Cornet",
"F.",
""
],
[
"Canal",
"C. García",
""
],
[
"Gutiérrez",
"M.",
""
],
[
"Illana",
"J. I.",
""
],
[
"Learn... | The Antarctic Impulsive Transient Antenna (ANITA) experiment has observed two air shower events with energy $\sim 500~{\rm PeV}$ emerging from the Earth with exit angles $\sim 30^\circ$ above the horizon. As was immediately noted by the ANITA Collaboration, these events (in principle) could originate in the atmospheric decay of an upgoing $\tau$-lepton produced through a charged current interaction of a $\nu_\tau$ inside the Earth. However, the relatively steep arrival angles of these perplexing events create tension with the standard model (SM) neutrino-nucleon interaction cross section. Deepening the conundrum, the IceCube neutrino telescope and the Pierre Auger Observatory with substantially larger exposures to cosmic $\nu_\tau$'s in this energy range have not observed any events. This lack of observation implies that the messenger particle (MP) giving rise to ANITA events must produce an air shower event rate at least a factor of 40 larger than that produced by a flux of $\tau$-neutrinos to avoid conflicts with the upper limits reported by the IceCube and the Pierre Auger collaborations. In addition, the sensitivity of ANITA to MP-induced events must be comparable to or larger than those of IceCube and Auger to avoid conflict with the non-observation of any signal at these facilities. Beyond SM interpretations of ANITA events can be classified according to whether the MPs: (i) live inside the Earth, (ii) originate in neutrino-nucleon collisions inside the Earth, (iii) come from cosmological distances. In this communication we investigate the positive and negative facets of these three classes of models. |
hep-ph/9506305 | Dimitrios Kominis | Dimitris Kominis | Flavor-Changing Neutral Current Constraints in Topcolor-Assisted
Technicolor | 11 pages, plain LaTeX | Phys.Lett.B358:312-317,1995 | 10.1016/0370-2693(95)01047-T | BUHEP-95-20 | hep-ph | null | It is argued that the topcolor models recently proposed by Hill [1] may face
significant constraints from flavor-changing neutral current processes (such as
$B-\bar{B}$ mixing) unless the mixing angles between down-type quarks are
small. The flavor-changing processes are mediated by scalar bound states which
are likely to be light as a result of the near critical dynamics of the
$b$-quark sector. The consequences of the latter on the bottom quark mass are
also briefly discussed.
| [
{
"created": "Mon, 12 Jun 1995 21:24:49 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Kominis",
"Dimitris",
""
]
] | It is argued that the topcolor models recently proposed by Hill [1] may face significant constraints from flavor-changing neutral current processes (such as $B-\bar{B}$ mixing) unless the mixing angles between down-type quarks are small. The flavor-changing processes are mediated by scalar bound states which are likely to be light as a result of the near critical dynamics of the $b$-quark sector. The consequences of the latter on the bottom quark mass are also briefly discussed. |
1809.04511 | Armando Bermudez Martinez | A. Bermudez Martinez, P. Connor, F. Hautmann, H. Jung, A. Lelek, V.
Radescu, R. Zlebcik | Determination and application of TMD parton densities using the Parton
Branching method | null | null | null | DESY 18-156 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a determination of parton densities at NLO obtained with the
Parton Branching method using precision measurements of deep inelastic
scattering cross sections at HERA. The two sets of parton densities shown in
this work are obtained with the same angular angular ordering condition for the
evolution scale and they differ in the chosen scale for the strong coupling
evaluation, for which we consider two scenarios: the evolution scale, and the
transverse momentum qT from the angular ordering prescription. The transverse
momentum dependent densities obtained with the Parton Branching method are
applied to two LHC processes: the Drell-Yan pT spectrum and the azimuthal
correlation in high pT dijet events. For the Drell-Yan pT spectrum a
significant effect from the strong coupling scale choice is observed.
| [
{
"created": "Wed, 12 Sep 2018 15:28:17 GMT",
"version": "v1"
}
] | 2018-09-13 | [
[
"Martinez",
"A. Bermudez",
""
],
[
"Connor",
"P.",
""
],
[
"Hautmann",
"F.",
""
],
[
"Jung",
"H.",
""
],
[
"Lelek",
"A.",
""
],
[
"Radescu",
"V.",
""
],
[
"Zlebcik",
"R.",
""
]
] | We present a determination of parton densities at NLO obtained with the Parton Branching method using precision measurements of deep inelastic scattering cross sections at HERA. The two sets of parton densities shown in this work are obtained with the same angular angular ordering condition for the evolution scale and they differ in the chosen scale for the strong coupling evaluation, for which we consider two scenarios: the evolution scale, and the transverse momentum qT from the angular ordering prescription. The transverse momentum dependent densities obtained with the Parton Branching method are applied to two LHC processes: the Drell-Yan pT spectrum and the azimuthal correlation in high pT dijet events. For the Drell-Yan pT spectrum a significant effect from the strong coupling scale choice is observed. |
0908.1297 | Sergey Gevorkyan | S. Gevorkyan, A. Gasparian, L. Gan, I. Larin, M. Khandaker | Incoherent photoproduction of pseudoscalar mesons off nuclei at forward
angles | 12 pages,2 figures | Physics of Particles and Nuclei Letters 9, 18 (2012) | 10.1134/S1547477112010116 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent advances in the photon tagging facilities together with the novel,
high resolution fast calorimetry made possible to perform photoproduction cross
section measurements of pseudoscalar mesons on nuclei with a percent level
accuracy. The extraction of the radiative decay widths, needed for testing the
symmetry breaking effects in QCD, from these measurements at small angles is
done by the Primakoff method. This method requires theoretical treatment of all
processes participating in these reactions at the same percent level. The most
updated description of general processes, including the nuclear coherent
amplitude, is done in our previous paper. In this work, based on the framework
of Glauber multiple scattering theory, we obtain analytical expressions for the
incoherent cross section of the photoproduction of pseudoscalar mesons off
nuclei accounting for the mesons absorption in nuclei and Pauli suppression at
forward production angles. As illustrations of the obtained formulas, we
calculate the incoherent cross section for photoproduction from a closed shell
nucleus, 16^O, and from an unclosed shell nucleus, 12^C. These calculations
allow one to compare different approaches and estimate their impact on the
incoherent cross section of the processes under consideration.
| [
{
"created": "Mon, 10 Aug 2009 10:42:37 GMT",
"version": "v1"
}
] | 2015-05-13 | [
[
"Gevorkyan",
"S.",
""
],
[
"Gasparian",
"A.",
""
],
[
"Gan",
"L.",
""
],
[
"Larin",
"I.",
""
],
[
"Khandaker",
"M.",
""
]
] | Recent advances in the photon tagging facilities together with the novel, high resolution fast calorimetry made possible to perform photoproduction cross section measurements of pseudoscalar mesons on nuclei with a percent level accuracy. The extraction of the radiative decay widths, needed for testing the symmetry breaking effects in QCD, from these measurements at small angles is done by the Primakoff method. This method requires theoretical treatment of all processes participating in these reactions at the same percent level. The most updated description of general processes, including the nuclear coherent amplitude, is done in our previous paper. In this work, based on the framework of Glauber multiple scattering theory, we obtain analytical expressions for the incoherent cross section of the photoproduction of pseudoscalar mesons off nuclei accounting for the mesons absorption in nuclei and Pauli suppression at forward production angles. As illustrations of the obtained formulas, we calculate the incoherent cross section for photoproduction from a closed shell nucleus, 16^O, and from an unclosed shell nucleus, 12^C. These calculations allow one to compare different approaches and estimate their impact on the incoherent cross section of the processes under consideration. |
hep-ph/0703073 | J\'er\^ome Charles | J. Charles, A. Hoecker, H. Lacker, F. Le Diberder, S. T'Jampens | Reply to: ''Improved Determination of the CKM Angle alpha from B -> pipi
decays'' | 5 pages, 1 figure. Fig. 1 corrected (wrong file) | null | null | CPT-P08-2007,LAPP-EXP-2007-01 | hep-ph | null | In reply to hep-ph/0701204 we demonstrate why the arguments made therein do
not address the criticism exposed in hep-ph/0607246 on the fundamental
shortcomings of the Bayesian approach when it comes to the extraction of
parameters of Nature from experimental data. As for the isospin analysis and
the CKM angle alpha it is shown that the use of uniform priors for the observed
quantities in the Explicit Solution parametrization is equivalent to a
frequentist construction resulting from a change of variables, and thus relies
neither on prior PDFs nor on Bayes' theorem. This procedure provides in this
particular case results that are similar to the Confidence Level approach, but
the treatment of mirror solutions remains incorrect and it is far from being
general. In a second part it is shown that important differences subsist
between the Bayesian and frequentist approaches, when following the proposal of
hep-ph/0701204 and inserting additional information on the hadronic amplitudes
beyond isospin invariance. In particular the frequentist result preserves the
exact degeneracy that is expected from the remaining symmetries of the problem
while the Bayesian procedure does not. Moreover, in the Bayesian approach
reducing inference to the 68% or 95% credible interval is a misconception of
the meaning of the posterior PDF, which in turn implies that the significant
dependence of the latter to the chosen parametrization cannot be viewed as a
minor effect, contrary to the claim in hep-ph/0701204.
| [
{
"created": "Wed, 7 Mar 2007 17:16:45 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Mar 2007 12:49:43 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Charles",
"J.",
""
],
[
"Hoecker",
"A.",
""
],
[
"Lacker",
"H.",
""
],
[
"Diberder",
"F. Le",
""
],
[
"T'Jampens",
"S.",
""
]
] | In reply to hep-ph/0701204 we demonstrate why the arguments made therein do not address the criticism exposed in hep-ph/0607246 on the fundamental shortcomings of the Bayesian approach when it comes to the extraction of parameters of Nature from experimental data. As for the isospin analysis and the CKM angle alpha it is shown that the use of uniform priors for the observed quantities in the Explicit Solution parametrization is equivalent to a frequentist construction resulting from a change of variables, and thus relies neither on prior PDFs nor on Bayes' theorem. This procedure provides in this particular case results that are similar to the Confidence Level approach, but the treatment of mirror solutions remains incorrect and it is far from being general. In a second part it is shown that important differences subsist between the Bayesian and frequentist approaches, when following the proposal of hep-ph/0701204 and inserting additional information on the hadronic amplitudes beyond isospin invariance. In particular the frequentist result preserves the exact degeneracy that is expected from the remaining symmetries of the problem while the Bayesian procedure does not. Moreover, in the Bayesian approach reducing inference to the 68% or 95% credible interval is a misconception of the meaning of the posterior PDF, which in turn implies that the significant dependence of the latter to the chosen parametrization cannot be viewed as a minor effect, contrary to the claim in hep-ph/0701204. |
2012.15190 | Atri Bhattacharya | Atri Bhattacharya, Rikard Enberg, Mary Hall Reno, Ina Sarcevic and
Anna Stasto | Perturbative Charm Production and the Prompt Atmospheric Neutrino Flux
in light of RHIC and LHC | Submission towards ICHEP2020 Proceedings | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Prompt neutrinos due to the decay of charmed mesons produced in the
atmosphere from cosmic-ray and atmospheric nuclei interactions may be a
significant source of background to ultra-high energy neutrino searches above
10 TeV. We re-evaluate this flux using updated charm production cross-sections
based on QCD parameters, the charm quark mass, and the range for the
factorization and renormalization scales that provide the best description of
this data at fixed target experiments, at RHIC, and at LHC. We find that the
prompt neutrino flux is reduced from previous results in the literature by a
factor between two and eight, depending on the energy. We discuss the
implications of our results for current IceCube data.
| [
{
"created": "Wed, 30 Dec 2020 15:23:02 GMT",
"version": "v1"
}
] | 2021-01-01 | [
[
"Bhattacharya",
"Atri",
""
],
[
"Enberg",
"Rikard",
""
],
[
"Reno",
"Mary Hall",
""
],
[
"Sarcevic",
"Ina",
""
],
[
"Stasto",
"Anna",
""
]
] | Prompt neutrinos due to the decay of charmed mesons produced in the atmosphere from cosmic-ray and atmospheric nuclei interactions may be a significant source of background to ultra-high energy neutrino searches above 10 TeV. We re-evaluate this flux using updated charm production cross-sections based on QCD parameters, the charm quark mass, and the range for the factorization and renormalization scales that provide the best description of this data at fixed target experiments, at RHIC, and at LHC. We find that the prompt neutrino flux is reduced from previous results in the literature by a factor between two and eight, depending on the energy. We discuss the implications of our results for current IceCube data. |
2305.04646 | John Andrew Raine | Debajyoti Sengupta, Samuel Klein, John Andrew Raine, Tobias Golling | CURTAINs Flows For Flows: Constructing Unobserved Regions with Maximum
Likelihood Estimation | 19 pages, 10 figures, 4 tables | null | null | null | hep-ph cs.LG hep-ex | http://creativecommons.org/licenses/by/4.0/ | Model independent techniques for constructing background data templates using
generative models have shown great promise for use in searches for new physics
processes at the LHC. We introduce a major improvement to the CURTAINs method
by training the conditional normalizing flow between two side-band regions
using maximum likelihood estimation instead of an optimal transport loss. The
new training objective improves the robustness and fidelity of the transformed
data and is much faster and easier to train.
We compare the performance against the previous approach and the current
state of the art using the LHC Olympics anomaly detection dataset, where we see
a significant improvement in sensitivity over the original CURTAINs method.
Furthermore, CURTAINsF4F requires substantially less computational resources to
cover a large number of signal regions than other fully data driven approaches.
When using an efficient configuration, an order of magnitude more models can be
trained in the same time required for ten signal regions, without a significant
drop in performance.
| [
{
"created": "Mon, 8 May 2023 11:58:49 GMT",
"version": "v1"
}
] | 2023-05-09 | [
[
"Sengupta",
"Debajyoti",
""
],
[
"Klein",
"Samuel",
""
],
[
"Raine",
"John Andrew",
""
],
[
"Golling",
"Tobias",
""
]
] | Model independent techniques for constructing background data templates using generative models have shown great promise for use in searches for new physics processes at the LHC. We introduce a major improvement to the CURTAINs method by training the conditional normalizing flow between two side-band regions using maximum likelihood estimation instead of an optimal transport loss. The new training objective improves the robustness and fidelity of the transformed data and is much faster and easier to train. We compare the performance against the previous approach and the current state of the art using the LHC Olympics anomaly detection dataset, where we see a significant improvement in sensitivity over the original CURTAINs method. Furthermore, CURTAINsF4F requires substantially less computational resources to cover a large number of signal regions than other fully data driven approaches. When using an efficient configuration, an order of magnitude more models can be trained in the same time required for ten signal regions, without a significant drop in performance. |
0804.1719 | Eibun Senaha | Cheng-Wei Chiang, Eibun Senaha | CP violation in the secluded U(1)'-extended MSSM | 28 pages, 16 figures, JHEP style | JHEP 0806:019,2008 | 10.1088/1126-6708/2008/06/019 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the Higgs sector of the secluded $U(1)'$-extended MSSM (sMSSM)
focusing on CP violation. Using the one-loop effective potential that includes
contributions from quarks and squarks in the third generation, we search for
the allowed region under theoretical and experimental constraints. It is found
that the possible region for the electroweak vacuum to exist is quite limited,
depending on the parameters in the model. The masses and couplings of the Higgs
bosons are calculated with/without CP violation. Even at the tree level, CP
violation is possible by complex soft SUSY breaking masses. Similar to the CPX
scenario in the MSSM, the scalar-pseudoscalar mixing enables the lightest Higgs
boson mass to become smaller than the $Z$ boson mass while the coupling with
the $Z$ boson is sufficiently suppressed to avoid the LEP experimental
constraints. However, unlike the CPX scenario, large $\mu$ and $A$ are not
required for the realization of large CP violation. The typical spectrum of the
SUSY particles is thus different. We also investigate the possible upper bound
of the lightest Higgs boson in the case of spontaneous CP violation. The
maximal value of it can reach above 100 GeV with maximal CP-violating phases.
| [
{
"created": "Thu, 10 Apr 2008 14:23:30 GMT",
"version": "v1"
}
] | 2009-01-06 | [
[
"Chiang",
"Cheng-Wei",
""
],
[
"Senaha",
"Eibun",
""
]
] | We study the Higgs sector of the secluded $U(1)'$-extended MSSM (sMSSM) focusing on CP violation. Using the one-loop effective potential that includes contributions from quarks and squarks in the third generation, we search for the allowed region under theoretical and experimental constraints. It is found that the possible region for the electroweak vacuum to exist is quite limited, depending on the parameters in the model. The masses and couplings of the Higgs bosons are calculated with/without CP violation. Even at the tree level, CP violation is possible by complex soft SUSY breaking masses. Similar to the CPX scenario in the MSSM, the scalar-pseudoscalar mixing enables the lightest Higgs boson mass to become smaller than the $Z$ boson mass while the coupling with the $Z$ boson is sufficiently suppressed to avoid the LEP experimental constraints. However, unlike the CPX scenario, large $\mu$ and $A$ are not required for the realization of large CP violation. The typical spectrum of the SUSY particles is thus different. We also investigate the possible upper bound of the lightest Higgs boson in the case of spontaneous CP violation. The maximal value of it can reach above 100 GeV with maximal CP-violating phases. |
0912.3523 | Christopher Lee | Vincenzo Cirigliano, Christopher Lee, Michael J. Ramsey-Musolf, and
Sean Tulin | Flavored Quantum Boltzmann Equations | 41 pages, 7 figures. v2: references added, minor corrections and
clarifications | Phys.Rev.D81:103503,2010 | 10.1103/PhysRevD.81.103503 | LAUR-09-08118, NPAC-09-16, UCB-PTH-09/37 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive from first principles, using non-equilibrium field theory, the
quantum Boltzmann equations that describe the dynamics of flavor oscillations,
collisions, and a time-dependent mass matrix in the early universe. Working to
leading non-trivial order in ratios of relevant time scales, we study in detail
a toy model for weak scale baryogenesis: two scalar species that mix through a
slowly varying time-dependent and CP-violating mass matrix, and interact with a
thermal bath. This model clearly illustrates how the CP asymmetry arises
through coherent flavor oscillations in a non-trivial background. We solve the
Boltzmann equations numerically for the density matrices, investigating the
impact of collisions in various regimes.
| [
{
"created": "Fri, 18 Dec 2009 17:23:37 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Feb 2010 06:26:13 GMT",
"version": "v2"
}
] | 2010-05-25 | [
[
"Cirigliano",
"Vincenzo",
""
],
[
"Lee",
"Christopher",
""
],
[
"Ramsey-Musolf",
"Michael J.",
""
],
[
"Tulin",
"Sean",
""
]
] | We derive from first principles, using non-equilibrium field theory, the quantum Boltzmann equations that describe the dynamics of flavor oscillations, collisions, and a time-dependent mass matrix in the early universe. Working to leading non-trivial order in ratios of relevant time scales, we study in detail a toy model for weak scale baryogenesis: two scalar species that mix through a slowly varying time-dependent and CP-violating mass matrix, and interact with a thermal bath. This model clearly illustrates how the CP asymmetry arises through coherent flavor oscillations in a non-trivial background. We solve the Boltzmann equations numerically for the density matrices, investigating the impact of collisions in various regimes. |
1002.1922 | Martin White Dr | M. J. White and F. Feroz | MSSM dark matter measurements at the LHC without squarks and sleptons | null | JHEP 1007:064,2010 | 10.1007/JHEP07(2010)064 | Cavendish-HEP-2010-02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the case of neutralino dark matter in the focus point region of
the MSSM, in which the scalar sparticles are too heavy to be produced at the
LHC. Whilst it has been previously asserted that the LHC alone would fail to
constrain the properties of the lightest neutralino for such a scenario, we
find that one can obtain good predictions of astrophysical quantities such as
the relic density, annihilation cross-section and direct search cross-sections
by using the shape of the dilepton invariant mass spectrum to constrain
neutralino mixing. We demonstrate our technique using a Bayesian analysis of
the 24 parameter MSSM model space, and in the process introduce a novel way of
improving the LHC results even without assumptions on which new sparticles are
responsible for the kinematic features in the dilepton invariant mass
distribution.
| [
{
"created": "Tue, 9 Feb 2010 17:51:28 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"White",
"M. J.",
""
],
[
"Feroz",
"F.",
""
]
] | We examine the case of neutralino dark matter in the focus point region of the MSSM, in which the scalar sparticles are too heavy to be produced at the LHC. Whilst it has been previously asserted that the LHC alone would fail to constrain the properties of the lightest neutralino for such a scenario, we find that one can obtain good predictions of astrophysical quantities such as the relic density, annihilation cross-section and direct search cross-sections by using the shape of the dilepton invariant mass spectrum to constrain neutralino mixing. We demonstrate our technique using a Bayesian analysis of the 24 parameter MSSM model space, and in the process introduce a novel way of improving the LHC results even without assumptions on which new sparticles are responsible for the kinematic features in the dilepton invariant mass distribution. |
2312.10677 | Mehran Dehpour | Mehran Dehpour | Thermal leptogenesis in anisotropic cosmology | 16 pages, 5 figures | Int.J.Mod.Phys.A 38 (2023) 35n36, 2350181 | 10.1142/S0217751X23501816 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There is no evidence that the universe must have been homogeneous and
isotropic before the big bang nucleosynthesis. The Bianchi type-I cosmology is
the simplest homogeneous but anisotropic cosmology. In this work, we
investigate thermal leptogenesis, as a baryogenesis scenario, in the Bianchi
type-I cosmology. Our results show that for specific values of the anisotropy,
the modified thermal leptogenesis generated more baryon asymmetry than the
standard one. In this way, anisotropy can help to achieve low-scale
leptogenesis.
| [
{
"created": "Sun, 17 Dec 2023 10:25:30 GMT",
"version": "v1"
}
] | 2024-03-26 | [
[
"Dehpour",
"Mehran",
""
]
] | There is no evidence that the universe must have been homogeneous and isotropic before the big bang nucleosynthesis. The Bianchi type-I cosmology is the simplest homogeneous but anisotropic cosmology. In this work, we investigate thermal leptogenesis, as a baryogenesis scenario, in the Bianchi type-I cosmology. Our results show that for specific values of the anisotropy, the modified thermal leptogenesis generated more baryon asymmetry than the standard one. In this way, anisotropy can help to achieve low-scale leptogenesis. |
0907.4774 | Kazem Azizi | K. Azizi, M. Bayar, A. Ozpineci, Y. Sarac | Tree Level Semileptonic $\Sigma_{b}$ to Nucleon Decay in Light Cone QCD
Sum Rules | 15 Pages, 1 Figure and 10 Tables | Phys.Rev.D80:036007,2009 | 10.1103/PhysRevD.80.036007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the most general form of the interpolating current of the heavy spin
1/2, $\Sigma_{b}$ baryon and distribution amplitudes of the nucleon, the
transition form factors of the semileptonic $\Sigma_{b}\to Nl\nu$ decay are
calculated in the framework of light cone QCD sum rules. It is obtained that
the form factors satisfy the heavy quark effective theory relations. The
obtained results for the related form factors are used to estimate the decay
rate of this transition.
| [
{
"created": "Mon, 27 Jul 2009 21:26:31 GMT",
"version": "v1"
}
] | 2009-09-02 | [
[
"Azizi",
"K.",
""
],
[
"Bayar",
"M.",
""
],
[
"Ozpineci",
"A.",
""
],
[
"Sarac",
"Y.",
""
]
] | Using the most general form of the interpolating current of the heavy spin 1/2, $\Sigma_{b}$ baryon and distribution amplitudes of the nucleon, the transition form factors of the semileptonic $\Sigma_{b}\to Nl\nu$ decay are calculated in the framework of light cone QCD sum rules. It is obtained that the form factors satisfy the heavy quark effective theory relations. The obtained results for the related form factors are used to estimate the decay rate of this transition. |
1003.0047 | Marco Ruggieri | Kenji Fukushima, Marco Ruggieri and Raoul Gatto | Chiral magnetic effect in the PNJL model | Some reference added. Minor revisions. One figure added. To appear on
Phys. Rev. D | Phys.Rev.D81:114031,2010 | 10.1103/PhysRevD.81.114031 | YITP-10-3 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the two-flavor Nambu--Jona-Lasinio model with the Polyakov loop
(PNJL model) in the presence of a strong magnetic field and a chiral chemical
potential $\mu_5$ which mimics the effect of imbalanced chirality due to QCD
instanton and/or sphaleron transitions. Firstly we focus on the properties of
chiral symmetry breaking and deconfinement crossover under the strong magnetic
field. Then we discuss the role of $\mu_5$ on the phase structure. Finally the
chirality charge, electric current, and their susceptibility, which are
relevant to the Chiral Magnetic Effect, are computed in the model.
| [
{
"created": "Sat, 27 Feb 2010 02:22:55 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Jun 2010 06:01:49 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Fukushima",
"Kenji",
""
],
[
"Ruggieri",
"Marco",
""
],
[
"Gatto",
"Raoul",
""
]
] | We study the two-flavor Nambu--Jona-Lasinio model with the Polyakov loop (PNJL model) in the presence of a strong magnetic field and a chiral chemical potential $\mu_5$ which mimics the effect of imbalanced chirality due to QCD instanton and/or sphaleron transitions. Firstly we focus on the properties of chiral symmetry breaking and deconfinement crossover under the strong magnetic field. Then we discuss the role of $\mu_5$ on the phase structure. Finally the chirality charge, electric current, and their susceptibility, which are relevant to the Chiral Magnetic Effect, are computed in the model. |
1805.06471 | Srimoyee Sen | Srimoyee Sen | Plasma Effects on Lasing of Uniform Ultralight Axion Condensate | New references added | Phys. Rev. D 98, 103012 (2018) | 10.1103/PhysRevD.98.103012 | INT-PUB-18-020 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Lasing of ultralight axion condensate into photons can be sensitive to the
presence of a background plasma owing to its coupling to electromagnetism. Such
a scenario is particularly relevant for superradiant axion condensate around
stellar mass black holes since the axion mass can be within a few orders of
magnitude of the plasma frequency of the surrounding medium. In this paper I
discuss the properties of the plasma around a black hole and analyze its
effects on the lasing of a uniform axion condensate of mass of the order of the
plasma frequency.
| [
{
"created": "Wed, 16 May 2018 18:00:19 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Jun 2018 21:08:17 GMT",
"version": "v2"
},
{
"created": "Wed, 15 Aug 2018 18:01:08 GMT",
"version": "v3"
},
{
"created": "Mon, 19 Nov 2018 16:58:48 GMT",
"version": "v4"
}
] | 2018-11-21 | [
[
"Sen",
"Srimoyee",
""
]
] | Lasing of ultralight axion condensate into photons can be sensitive to the presence of a background plasma owing to its coupling to electromagnetism. Such a scenario is particularly relevant for superradiant axion condensate around stellar mass black holes since the axion mass can be within a few orders of magnitude of the plasma frequency of the surrounding medium. In this paper I discuss the properties of the plasma around a black hole and analyze its effects on the lasing of a uniform axion condensate of mass of the order of the plasma frequency. |
2306.04045 | Rui Wen | Rui Wen, Shi Yin, Wei-jie Fu, Mei Huang | Functional renormalization group study of neutral and charged pion under
magnetic fields in the quark-meson model | 10 pages, 5 figures | null | 10.1103/PhysRevD.108.076020 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We calculated the masses of neutral and charged pion and pion decay constants
under an extra magnetic field at zero temperature. The quantum fluctuations are
integrated through the functional renormalization group. We consider the quark
and meson propagators in the Landau level representation and weak-field
expansion, respectively. The neutral pion mass monotonically decreases with the
magnetic field, while the charged pion mass monotonically increases with the
magnetic field. The pion decay constant and the quark mass show the magnetic
catalysis behavior at vanishing temperature. The neutral pion mass and pion
decay constant are quantitatively in agreement with the lattice QCD results in
the region of $eB < 1.2 {\rm GeV}^2$, and no non-monotonic mass behavior for
charged pion has been observed in this framework.
| [
{
"created": "Tue, 6 Jun 2023 22:21:33 GMT",
"version": "v1"
}
] | 2024-03-13 | [
[
"Wen",
"Rui",
""
],
[
"Yin",
"Shi",
""
],
[
"Fu",
"Wei-jie",
""
],
[
"Huang",
"Mei",
""
]
] | We calculated the masses of neutral and charged pion and pion decay constants under an extra magnetic field at zero temperature. The quantum fluctuations are integrated through the functional renormalization group. We consider the quark and meson propagators in the Landau level representation and weak-field expansion, respectively. The neutral pion mass monotonically decreases with the magnetic field, while the charged pion mass monotonically increases with the magnetic field. The pion decay constant and the quark mass show the magnetic catalysis behavior at vanishing temperature. The neutral pion mass and pion decay constant are quantitatively in agreement with the lattice QCD results in the region of $eB < 1.2 {\rm GeV}^2$, and no non-monotonic mass behavior for charged pion has been observed in this framework. |
hep-ph/9710225 | Thomas Gajdosik | Ekaterina Christova and Dimitar Draganov | On the top-quark polarization and how to measure it | 9 pages, LaTex, 3 ps.figures | Phys.Lett. B434 (1998) 373-378 | 10.1016/S0370-2693(98)00630-3 | INRNE-TH-97/08 | hep-ph | null | The top quark is expected to decay as a free particle with definite momentum
and polarization. Here we consider the possibilities to obtain information
about its polarization through the energy and angular distributions of the
b-quarks from the decay of the top-quarks produced in $e^+e^-$ annihilation.
Analytic expressions and numerical estimates for different beam polarizations
are derived.
| [
{
"created": "Thu, 2 Oct 1997 17:08:44 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Christova",
"Ekaterina",
""
],
[
"Draganov",
"Dimitar",
""
]
] | The top quark is expected to decay as a free particle with definite momentum and polarization. Here we consider the possibilities to obtain information about its polarization through the energy and angular distributions of the b-quarks from the decay of the top-quarks produced in $e^+e^-$ annihilation. Analytic expressions and numerical estimates for different beam polarizations are derived. |
2004.04213 | Hubert Spiesberger | B. A. Kniehl, G. Kramer, I. Schienbein and H. Spiesberger | $\Lambda_c^{\pm}$ production in pp collisions with a new fragmentation
function | 21 pages | Phys. Rev. D 101, 114021 (2020) | 10.1103/PhysRevD.101.114021 | DESY 20-058, MITP/20-015 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study inclusive $\Lambda_c^{\pm}$-baryon production in $pp$ collisions in
the general-mass variable-flavor number scheme and compare with data from the
LHCb, ALICE and CMS collaborations. We perform a new fit of the $c \to
\Lambda_c^+$ fragmentation function combining $e^+e^-$ data from OPAL and
Belle. The agreement with LHC data is slightly worse compared with a
calculation using an older fragmentation function, and the tension between
different determinations of $\Lambda_c^{\pm}$ production cross sections from
the LHC experimental collaborations is not resolved. The ratio of data for
$\Lambda_c^+$-baryon and $D^0$-meson production seems to violate the
universality of $c$-charm quark to $c$-hadron fragmentation.
| [
{
"created": "Wed, 8 Apr 2020 19:22:20 GMT",
"version": "v1"
}
] | 2020-07-01 | [
[
"Kniehl",
"B. A.",
""
],
[
"Kramer",
"G.",
""
],
[
"Schienbein",
"I.",
""
],
[
"Spiesberger",
"H.",
""
]
] | We study inclusive $\Lambda_c^{\pm}$-baryon production in $pp$ collisions in the general-mass variable-flavor number scheme and compare with data from the LHCb, ALICE and CMS collaborations. We perform a new fit of the $c \to \Lambda_c^+$ fragmentation function combining $e^+e^-$ data from OPAL and Belle. The agreement with LHC data is slightly worse compared with a calculation using an older fragmentation function, and the tension between different determinations of $\Lambda_c^{\pm}$ production cross sections from the LHC experimental collaborations is not resolved. The ratio of data for $\Lambda_c^+$-baryon and $D^0$-meson production seems to violate the universality of $c$-charm quark to $c$-hadron fragmentation. |
0807.0270 | Peihong Gu | Pei-Hong Gu, Utpal Sarkar | Radiative seesaw in left-right symmetric model | 5 pages, 3 figures. Revised version with minor change. Accepted by
PRD | Phys.Rev.D78:073012,2008 | 10.1103/PhysRevD.78.073012 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There are some radiative origins for the neutrino masses in the conventional
left-right symmetric models with the usual bi-doublet and triplet Higgs
scalars. These radiative contributions could dominate over the tree-level
seesaw and could explain the observed neutrino masses.
| [
{
"created": "Wed, 2 Jul 2008 05:05:33 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Oct 2008 15:51:09 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Gu",
"Pei-Hong",
""
],
[
"Sarkar",
"Utpal",
""
]
] | There are some radiative origins for the neutrino masses in the conventional left-right symmetric models with the usual bi-doublet and triplet Higgs scalars. These radiative contributions could dominate over the tree-level seesaw and could explain the observed neutrino masses. |
hep-ph/0007304 | Kenneth Lane | Kenneth Lane | Technicolor 2000 | 46 pages, 21 figures, using Latex with frascatiphys.sty. Lectures at
the LNF Spring School in Nuclear, Subnuclear and Astroparticle Physics,
Frascati (Rome), Italy, May 15-20, 2000 | null | null | Boston University Report BUHEP-00-15 | hep-ph hep-ex | null | This review is based on lectures on technicolor and extended technicolor
presented at the Frascati Spring School in May 2000. I summarize the motivation
and structure of this theory of dynamical breaking of electroweak and flavor
symmetries. Particular attention is paid to the main phenomenological obstacles
to this picture-flavor-changing neutral currents, precision electroweak
measurements, and the large top-quark mass-and their proposed
resolutions-walking technicolor and topcolor-assisted technicolor. I then
discuss the signatures for technicolor and the existing and upcoming searches
for them at LEP, the Tevatron Collider, and the Large Hadron Collider. The
final section lists some outstanding theoretical questions.
| [
{
"created": "Wed, 26 Jul 2000 17:36:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lane",
"Kenneth",
""
]
] | This review is based on lectures on technicolor and extended technicolor presented at the Frascati Spring School in May 2000. I summarize the motivation and structure of this theory of dynamical breaking of electroweak and flavor symmetries. Particular attention is paid to the main phenomenological obstacles to this picture-flavor-changing neutral currents, precision electroweak measurements, and the large top-quark mass-and their proposed resolutions-walking technicolor and topcolor-assisted technicolor. I then discuss the signatures for technicolor and the existing and upcoming searches for them at LEP, the Tevatron Collider, and the Large Hadron Collider. The final section lists some outstanding theoretical questions. |
hep-ph/9506460 | null | Christopher D. Carone and Hitoshi Murayama | Light U(1) Gauge Boson Coupled to Baryon Number | 8pp. LaTeX, 5 figures included as uuencoded, gzipped, encapsulated
postscript files. Talk presented by C. Carone at the Workshop on Particle
Theory and Phenomenology, May 17-19, 1995, Iowa State University, Ames Iowa.
Full postscript available from
http://theor1.lbl.gov/www/theorgroup/papers/37432.ps | null | null | LBL-37432 | hep-ph | null | We discuss the phenomenology of a light U(1) gauge boson, $\gamma_B$, that
couples only to baryon number. Gauging baryon number at high energies can
prevent dangerous baryon-number violating operators that may be generated by
Planck scale physics. However, we assume at low energies that the new U(1)
gauge symmetry is spontaneously broken and that the $\gamma_B$ mass $m_B$ is
smaller than $m_Z$. We show for $m_\Upsilon<m_B<m_Z$ that the $\gamma_B$
coupling $\alpha_B$ can be as large as $\sim 0.1$ without conflicting with the
current experimental constraints. We argue that $\alpha_B\sim 0.1$ is large
enough to produce visible collider signatures and that evidence for the
$\gamma_B$ could be hidden in existing LEP data. We show that there are
realistic models in which mixing between the $\gamma_B$ and the electroweak
gauge bosons occurs only as a radiative effect and does not lead to conflict
with precision electroweak measurements. Such mixing may nevertheless provide a
leptonic signal for models of this type at an upgraded Tevatron.
| [
{
"created": "Thu, 29 Jun 1995 22:37:31 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Jun 1995 18:17:05 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Carone",
"Christopher D.",
""
],
[
"Murayama",
"Hitoshi",
""
]
] | We discuss the phenomenology of a light U(1) gauge boson, $\gamma_B$, that couples only to baryon number. Gauging baryon number at high energies can prevent dangerous baryon-number violating operators that may be generated by Planck scale physics. However, we assume at low energies that the new U(1) gauge symmetry is spontaneously broken and that the $\gamma_B$ mass $m_B$ is smaller than $m_Z$. We show for $m_\Upsilon<m_B<m_Z$ that the $\gamma_B$ coupling $\alpha_B$ can be as large as $\sim 0.1$ without conflicting with the current experimental constraints. We argue that $\alpha_B\sim 0.1$ is large enough to produce visible collider signatures and that evidence for the $\gamma_B$ could be hidden in existing LEP data. We show that there are realistic models in which mixing between the $\gamma_B$ and the electroweak gauge bosons occurs only as a radiative effect and does not lead to conflict with precision electroweak measurements. Such mixing may nevertheless provide a leptonic signal for models of this type at an upgraded Tevatron. |
hep-ph/9911431 | null | Y. Nemoto, K. Naito, M. Oka | Effective Potential of O(N) Linear Sigma Model at Finite Temperature | 31 pages, LaTeX, 10 eps figures, uses epsf.sty | Eur.Phys.J.A9:245-259,2000 | 10.1007/s100500070042 | null | hep-ph | null | We study the O(N) symmetric linear sigma model at finite temperature as the
low-energy effective models of quantum chromodynamics(QCD) using the
Cornwall-Jackiw-Tomboulis(CJT) effective action for composite operators. It has
so far been claimed that the Nambu-Goldstone theorem is not satisfied at finite
temperature in this framework unless the large N limit in the O(N) symmetry is
taken. We show that this is not the case. The pion is always massless below the
critical temperature, if one determines the propagator within the form such
that the symmetry of the system is conserved, and defines the pion mass as the
curvature of the effective potential. We use a new renormalization prescription
for the CJT effective potential in the Hartree-Fock approximation. A numerical
study of the Schwinger-Dyson equation and the gap equation is carried out
including the thermal and quantum loops. We point out a problem in the
derivation of the sigma meson mass without quantum correction at finite
temperature. A problem about the order of the phase transition in this approach
is also discussed.
| [
{
"created": "Mon, 22 Nov 1999 03:27:23 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Nemoto",
"Y.",
""
],
[
"Naito",
"K.",
""
],
[
"Oka",
"M.",
""
]
] | We study the O(N) symmetric linear sigma model at finite temperature as the low-energy effective models of quantum chromodynamics(QCD) using the Cornwall-Jackiw-Tomboulis(CJT) effective action for composite operators. It has so far been claimed that the Nambu-Goldstone theorem is not satisfied at finite temperature in this framework unless the large N limit in the O(N) symmetry is taken. We show that this is not the case. The pion is always massless below the critical temperature, if one determines the propagator within the form such that the symmetry of the system is conserved, and defines the pion mass as the curvature of the effective potential. We use a new renormalization prescription for the CJT effective potential in the Hartree-Fock approximation. A numerical study of the Schwinger-Dyson equation and the gap equation is carried out including the thermal and quantum loops. We point out a problem in the derivation of the sigma meson mass without quantum correction at finite temperature. A problem about the order of the phase transition in this approach is also discussed. |
0807.4805 | Tiago Charters | T. Charters, A. Nunes, J. P. Mimoso | Reheating induced by competing decay modes | 14 pages, 4 figures Added references. Corrected typos | Phys.Rev.D78:083539,2008 | 10.1103/PhysRevD.78.083539 | null | hep-ph gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We address the problem of studying the decay of the inflaton field $\phi$ to
another scalar field $\chi$ through parametric resonance in the case of a
coupling that involves several decay modes. This amounts to the presence of
extra harmonic terms in the perturbation of the $\chi$ field dynamics. For the
case of two frequencies we compute the geometry of the resonance regions, which
is significantly altered due to the presence of non-cuspidal resonance regions
associated to higher harmonics and to the emergence of instability `pockets'.
We discuss the effect of this change in the efficiency of the energy transfer
process for the simplest case of a coupling given by a combination of the two
interaction terms of homogeneous degree usually considered in the literature.
We find that the presence of higher harmonics has limited cosmological
implications.
| [
{
"created": "Wed, 30 Jul 2008 15:37:48 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Sep 2008 09:55:16 GMT",
"version": "v2"
}
] | 2010-05-12 | [
[
"Charters",
"T.",
""
],
[
"Nunes",
"A.",
""
],
[
"Mimoso",
"J. P.",
""
]
] | We address the problem of studying the decay of the inflaton field $\phi$ to another scalar field $\chi$ through parametric resonance in the case of a coupling that involves several decay modes. This amounts to the presence of extra harmonic terms in the perturbation of the $\chi$ field dynamics. For the case of two frequencies we compute the geometry of the resonance regions, which is significantly altered due to the presence of non-cuspidal resonance regions associated to higher harmonics and to the emergence of instability `pockets'. We discuss the effect of this change in the efficiency of the energy transfer process for the simplest case of a coupling given by a combination of the two interaction terms of homogeneous degree usually considered in the literature. We find that the presence of higher harmonics has limited cosmological implications. |
hep-ph/9206249 | Stephen Naculich | S. G. Naculich and C.-P. Yuan | Inelastic Channels in the Electroweak Symmetry-Breaking Sector | 10 pages, phyzzx, JHU-TIPAC-920012 | Phys.Lett.B293:405-409,1992 | 10.1016/0370-2693(92)90904-I | null | hep-ph | null | It has been argued that if light Higgs bosons do not exist then the
self--interactions of $W$'s become strong in the TeV region and can be observed
in longitudinal $WW$ scattering. We present a model with many inelastic
channels in the $WW$ scattering process, corresponding to the creation of heavy
fermion pairs. The presence of these heavy fermions affects the elastic
scattering of $W$'s by propagating in loops, greatly reducing the amplitudes in
some charge channels. Consequently, the symmetry--breaking sector cannot be
fully explored by using, for example, the $W^+W^+$ mode alone; all $WW
\rightarrow WW$ scattering modes must be measured.}
| [
{
"created": "Thu, 25 Jun 1992 20:54:00 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Naculich",
"S. G.",
""
],
[
"Yuan",
"C. -P.",
""
]
] | It has been argued that if light Higgs bosons do not exist then the self--interactions of $W$'s become strong in the TeV region and can be observed in longitudinal $WW$ scattering. We present a model with many inelastic channels in the $WW$ scattering process, corresponding to the creation of heavy fermion pairs. The presence of these heavy fermions affects the elastic scattering of $W$'s by propagating in loops, greatly reducing the amplitudes in some charge channels. Consequently, the symmetry--breaking sector cannot be fully explored by using, for example, the $W^+W^+$ mode alone; all $WW \rightarrow WW$ scattering modes must be measured.} |
hep-ph/9711454 | Toshiaki Ito | Toshiaki Ito, Naotoshi Okamura and Morimitsu Tanimoto | NNI Quark-Lepton Mass Matrices in SUSY SU(5) GUT | 7 pages, 1 figure using epsf.sty | Phys.Rev.D58:077301,1998; Erratum-ibid.D59:039902,1999 | 10.1103/PhysRevD.58.077301 10.1103/PhysRevD.59.039902 | DCE-APU-97-02/DPNU-97-54/EHU-97-11 | hep-ph | null | We propose the Fritzsch-Branco-Silva-Marcos type fermion mass matrix, which
is a typical texture in the nearest-neighbor interaction form, in SU(5) GUT. By
evolution of the mass matrices with SU(5) GUT relations in the minimal SUSY
standard model, we obtain predictions for the unitarity triangle of CP
violation as well as the quark flavor mixing angles, which are consistent with
experimental data, in the case of \tan\beta \simeq 3.
| [
{
"created": "Tue, 25 Nov 1997 03:55:14 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Ito",
"Toshiaki",
""
],
[
"Okamura",
"Naotoshi",
""
],
[
"Tanimoto",
"Morimitsu",
""
]
] | We propose the Fritzsch-Branco-Silva-Marcos type fermion mass matrix, which is a typical texture in the nearest-neighbor interaction form, in SU(5) GUT. By evolution of the mass matrices with SU(5) GUT relations in the minimal SUSY standard model, we obtain predictions for the unitarity triangle of CP violation as well as the quark flavor mixing angles, which are consistent with experimental data, in the case of \tan\beta \simeq 3. |
hep-ph/9405378 | null | J. Maalampi, J. Sirkka and I. Vilja | Baryon and lepton number transport in electroweak phase transition | 13 pages + 2 figures available on request, HU-TFT-94-15, TURKU-FL-P11 | Phys.Lett. B337 (1994) 122-127 | 10.1016/0370-2693(94)91454-0 | null | hep-ph | null | We consider the baryon number generation by charge transport mechanism in the
electroweak phase transition taking properly into account thermal fluxes
through the wall separating true and false vacuum in the spatial space. We show
that the diffusion from the true vacuum to the false one has a large
diminishing effect on the baryon number unless the wall velocity is near to,
but less than, the speed of sound in the medium and the ratio between the
collision rate and wall thickness is about 0.3. The maximum net baryon density
generated is $\rho_B/s\simeq 0.2\times 10^{-10}$, where $s$ is the entropy
density of the Universe. If the wall proceeds as a detonation, no baryon number
is produced.
| [
{
"created": "Wed, 25 May 1994 07:15:47 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Maalampi",
"J.",
""
],
[
"Sirkka",
"J.",
""
],
[
"Vilja",
"I.",
""
]
] | We consider the baryon number generation by charge transport mechanism in the electroweak phase transition taking properly into account thermal fluxes through the wall separating true and false vacuum in the spatial space. We show that the diffusion from the true vacuum to the false one has a large diminishing effect on the baryon number unless the wall velocity is near to, but less than, the speed of sound in the medium and the ratio between the collision rate and wall thickness is about 0.3. The maximum net baryon density generated is $\rho_B/s\simeq 0.2\times 10^{-10}$, where $s$ is the entropy density of the Universe. If the wall proceeds as a detonation, no baryon number is produced. |
hep-ph/0604266 | Adam Szczepaniak | Adam P. Szczepaniak and J.T. Londergan | Exclusive electroproduction and the quark structure of the nucleon | 11 pages, 1 figure, typos corrected, references added | Phys.Lett.B643:17-21,2006 | 10.1016/j.physletb.2006.10.028 | null | hep-ph | null | The natural interpretation of deep inelastic scattering is in terms of hard
scattering on QCD constituents of the target. We examine the relation between
amplitudes measured in exclusive lepto-production and the quark content of the
nucleon. We show that in the Bjorken limit, the natural interpretation of
amplitudes measured in these hard exclusive processes is in terms of the quark
content of the meson cloud and not the target itself. Therefore the most
efficient representation of these exclusive processes is in terms of leading
Regge amplitudes.
| [
{
"created": "Fri, 28 Apr 2006 13:07:36 GMT",
"version": "v1"
},
{
"created": "Sun, 18 Jun 2006 16:15:42 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Szczepaniak",
"Adam P.",
""
],
[
"Londergan",
"J. T.",
""
]
] | The natural interpretation of deep inelastic scattering is in terms of hard scattering on QCD constituents of the target. We examine the relation between amplitudes measured in exclusive lepto-production and the quark content of the nucleon. We show that in the Bjorken limit, the natural interpretation of amplitudes measured in these hard exclusive processes is in terms of the quark content of the meson cloud and not the target itself. Therefore the most efficient representation of these exclusive processes is in terms of leading Regge amplitudes. |
2007.00015 | Jessica Turner | Pedro Machado, Holger Schulz, Jessica Turner | Tau neutrinos at DUNE: new strategies, new opportunities | 10 pages, 9 figures. Figure labels enlarged, expanded captions and
included url for code in references. Matches PRD accepted version | Phys. Rev. D 102, 053010 (2020) | 10.1103/PhysRevD.102.053010 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a novel analysis strategy, that leverages the unique capabilities
of the DUNE experiment, to study tau neutrinos. We integrate collider physics
ideas, such as jet clustering algorithms in combination with machine learning
techniques, into neutrino measurements. Through the construction of a set of
observables and kinematic cuts, we obtain a superior discrimination of the
signal ($S$) over the background ($B$). In a single year, using the nominal
neutrino beam mode, DUNE may achieve $S/\sqrt{B}$ of $3.3$ and $2.3$ for the
hadronic and leptonic decay channels of the tau respectively. Operating in the
tau-optimized beam mode would increase $S/\sqrt{B}$ to $8.8$ and $11$ for each
of these channels. We premier the use of the analysis software Rivet, a tool
ubiquitously used by the LHC experiments, in neutrino physics. For wider
accessibility, we provide our analysis code.
| [
{
"created": "Tue, 30 Jun 2020 18:00:03 GMT",
"version": "v1"
},
{
"created": "Sat, 15 Aug 2020 01:58:22 GMT",
"version": "v2"
}
] | 2020-09-30 | [
[
"Machado",
"Pedro",
""
],
[
"Schulz",
"Holger",
""
],
[
"Turner",
"Jessica",
""
]
] | We propose a novel analysis strategy, that leverages the unique capabilities of the DUNE experiment, to study tau neutrinos. We integrate collider physics ideas, such as jet clustering algorithms in combination with machine learning techniques, into neutrino measurements. Through the construction of a set of observables and kinematic cuts, we obtain a superior discrimination of the signal ($S$) over the background ($B$). In a single year, using the nominal neutrino beam mode, DUNE may achieve $S/\sqrt{B}$ of $3.3$ and $2.3$ for the hadronic and leptonic decay channels of the tau respectively. Operating in the tau-optimized beam mode would increase $S/\sqrt{B}$ to $8.8$ and $11$ for each of these channels. We premier the use of the analysis software Rivet, a tool ubiquitously used by the LHC experiments, in neutrino physics. For wider accessibility, we provide our analysis code. |
1907.12294 | Maryam Soleymaninia | Maryam Soleymaninia and Hamzeh Khanpour | Transverse momentum dependent of charged pion, kaon and
proton/antiproton fragmentation functions from $e^+e^-$ annihilation process | 11 pages, 5 figures and 2 tables, Accepted for Publication in
Physical Review D | Phys. Rev. D 100, 094033 (2019) | 10.1103/PhysRevD.100.094033 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The main aim of this paper is a new determination of transverse momentum
dependence of unpolarized fragmentation function (TMD FFs) in single inclusive
hadron production in electron-positron annihilation (SIA) process. Motivated by
the need for a reliable and consistent determination of TMD FFs, we use the
most recent TMD production cross sections of charged pions ($\pi^\pm$), kaons
($K^\pm$) and protons/antiprotons ($p/\bar{p}$) measured in inclusive $e^+e^-$
collisions by Belle Collaboration. These datasets are the first transverse
momentum dependence of identified light charged hadron measurements SIA
process. In this analysis, referred to as {\tt SK19 TMD FFs}, the common
Gaussian distribution is used for the $P_{hT}$ dependent of the cross section.
The uncertainties in the extraction of {\tt SK19 TMD FFs} are estimated using
the standard "Hessian" technique. We study the quality of the TMD FFs
determined in this analysis by comparing with the available recent Belle cross
sections measurement. For all hadron species, we found a very good agreement
between this particular set of experimental data and the corresponding theory
calculations over a relatively wide range of transverse momentum $P_{hT}$. As a
result of this study, suggestions are identified for possible future research
considering the theory improvements and other available experimental
observables.
| [
{
"created": "Mon, 29 Jul 2019 09:31:43 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Nov 2019 18:14:09 GMT",
"version": "v2"
}
] | 2019-12-04 | [
[
"Soleymaninia",
"Maryam",
""
],
[
"Khanpour",
"Hamzeh",
""
]
] | The main aim of this paper is a new determination of transverse momentum dependence of unpolarized fragmentation function (TMD FFs) in single inclusive hadron production in electron-positron annihilation (SIA) process. Motivated by the need for a reliable and consistent determination of TMD FFs, we use the most recent TMD production cross sections of charged pions ($\pi^\pm$), kaons ($K^\pm$) and protons/antiprotons ($p/\bar{p}$) measured in inclusive $e^+e^-$ collisions by Belle Collaboration. These datasets are the first transverse momentum dependence of identified light charged hadron measurements SIA process. In this analysis, referred to as {\tt SK19 TMD FFs}, the common Gaussian distribution is used for the $P_{hT}$ dependent of the cross section. The uncertainties in the extraction of {\tt SK19 TMD FFs} are estimated using the standard "Hessian" technique. We study the quality of the TMD FFs determined in this analysis by comparing with the available recent Belle cross sections measurement. For all hadron species, we found a very good agreement between this particular set of experimental data and the corresponding theory calculations over a relatively wide range of transverse momentum $P_{hT}$. As a result of this study, suggestions are identified for possible future research considering the theory improvements and other available experimental observables. |
1107.5292 | Gordon Ramsey | Yevgeny Binder, Gordon P. Ramsey and Dennis Sivers | Studying Spin-Orbit Dynamics using Measurements of the Proton's
Polarized Gluon Asymmetry | 24 pages, 3 figures | null | null | ANL-HEP-PR-11-49 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Measurements involving the gluon spin density, Delta G=G++ - G+-, can play an
important role in the quantitative understanding of proton structure. To
demonstrate this, we show that the shape of the gluon asymmetry, A(x,t)=Delta
G(x,t)/G(x,t), contains significant dynamical information about
non-perturbative spin-orbit effects. It is instructive to use a separation
A(x,t)=A_0^epsilon(x)+epsilon(x,t), where A_0^epsilon(x) is an approximately
scale-invariant form that can be calculated within a given factorization
prescription from the measured distributions Delta q(x,t), q(x,t) and G(x,t).
Applying this separation with the J_z=1/2 sum rule provides a convenient way to
determine the total amount of orbital angular momentum generated by mechanisms
associated with confinement and chiral dynamics. The results are consistent
with alternate non-perturbative approaches to the determination of orbital
angular momentum in the proton. Our studies help to specify the accuracy that
future measurements should achieve to constrain theoretical models for nucleon
structure.
| [
{
"created": "Tue, 26 Jul 2011 18:46:34 GMT",
"version": "v1"
}
] | 2011-07-27 | [
[
"Binder",
"Yevgeny",
""
],
[
"Ramsey",
"Gordon P.",
""
],
[
"Sivers",
"Dennis",
""
]
] | Measurements involving the gluon spin density, Delta G=G++ - G+-, can play an important role in the quantitative understanding of proton structure. To demonstrate this, we show that the shape of the gluon asymmetry, A(x,t)=Delta G(x,t)/G(x,t), contains significant dynamical information about non-perturbative spin-orbit effects. It is instructive to use a separation A(x,t)=A_0^epsilon(x)+epsilon(x,t), where A_0^epsilon(x) is an approximately scale-invariant form that can be calculated within a given factorization prescription from the measured distributions Delta q(x,t), q(x,t) and G(x,t). Applying this separation with the J_z=1/2 sum rule provides a convenient way to determine the total amount of orbital angular momentum generated by mechanisms associated with confinement and chiral dynamics. The results are consistent with alternate non-perturbative approaches to the determination of orbital angular momentum in the proton. Our studies help to specify the accuracy that future measurements should achieve to constrain theoretical models for nucleon structure. |
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