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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/0402274 | Takashi Shimomura | Kanji Fujii and Takashi Shimomura | Expectation values of flavor-neutrino currents in field theoretical
approach to oscillation problem -- formulation | 31 pages, 12 figures | null | null | EPHOU-04-001 | hep-ph | null | As a possible approach to the neutrino oscillation on the basis of quantum
field theory, the expectation values of the flavor-neutrino currents are
investigated by employing the finite-time transition matrix in the interaction
representation. Such expectation values give us in the simplest form a possible
way of treating the neutrino oscillation without recourse to any one
flavor-neutrino states. The present paper is devoted to presenting the
formulation and the main structures of the relevant expectation values.
| [
{
"created": "Thu, 26 Feb 2004 09:12:47 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Fujii",
"Kanji",
""
],
[
"Shimomura",
"Takashi",
""
]
] | As a possible approach to the neutrino oscillation on the basis of quantum field theory, the expectation values of the flavor-neutrino currents are investigated by employing the finite-time transition matrix in the interaction representation. Such expectation values give us in the simplest form a possible way of treating the neutrino oscillation without recourse to any one flavor-neutrino states. The present paper is devoted to presenting the formulation and the main structures of the relevant expectation values. |
2312.09896 | Marco Niggetiedt | Micha{\l} Czakon, Felix Eschment, Marco Niggetiedt, Rene Poncelet, Tom
Schellenberger | Top-Bottom Interference Contribution to Fully-Inclusive Higgs Production | 6 pages, 1 table | Phys. Rev. Lett. 132, 211902 (2024) | 10.1103/PhysRevLett.132.211902 | P3H-23-101, TTK-23-34, MPP-2023-286, IFJPAN-IV-2023-6 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We evaluate the top-bottom interference contribution to the fully-inclusive
Higgs production cross section at next-to-next-to-leading order in QCD.
Although bottom-quark-mass effects are power-suppressed, the accuracy of
state-of-the-art theory predictions makes an exact determination of this effect
indispensable. The total effect of the interference at 13 TeV is
$-1.99(1)^{+0.30}_{-0.15}$ pb, while the pure $\mathcal{O}(\alpha_s^4)$
correction is 0.43 pb. With this result, we address one of the leading theory
uncertainties of the cross section.
| [
{
"created": "Fri, 15 Dec 2023 15:46:16 GMT",
"version": "v1"
},
{
"created": "Fri, 24 May 2024 07:31:28 GMT",
"version": "v2"
}
] | 2024-05-27 | [
[
"Czakon",
"Michał",
""
],
[
"Eschment",
"Felix",
""
],
[
"Niggetiedt",
"Marco",
""
],
[
"Poncelet",
"Rene",
""
],
[
"Schellenberger",
"Tom",
""
]
] | We evaluate the top-bottom interference contribution to the fully-inclusive Higgs production cross section at next-to-next-to-leading order in QCD. Although bottom-quark-mass effects are power-suppressed, the accuracy of state-of-the-art theory predictions makes an exact determination of this effect indispensable. The total effect of the interference at 13 TeV is $-1.99(1)^{+0.30}_{-0.15}$ pb, while the pure $\mathcal{O}(\alpha_s^4)$ correction is 0.43 pb. With this result, we address one of the leading theory uncertainties of the cross section. |
hep-ph/0607223 | Redamy Perez Ramos | Redamy Perez Ramos (LPTHE) | Single Inclusive Distribution and Two-Particle Correlations Inside One
Jet at "Modified Leading Logarithmic Approximation" of Quantum Chromodynamics
II : Steepest Descent Evaluation at Small X | LaTeX, 22 pages, 18 .eps figures | JHEP0609:014,2006 | 10.1088/1126-6708/2006/09/014 | null | hep-ph | null | The MLLA single inclusive distribution inside one high energy (gluon) jet at
small x is estimated by the steepest descent method. Its analytical expression
is obtained outside the "limiting spectrum". It is then used to evaluate
2-particle correlations at the same level of generality. The dependence of both
observables on the ratio between the infrared cutoff Q\_0 and Lambda\_QCD is
studied. Fong & Webber's results for correlations are recovered at the limits
when this ratio goes to 1 and when one stays close to the peak of the single
inclusive distribution.
| [
{
"created": "Thu, 20 Jul 2006 10:03:41 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Ramos",
"Redamy Perez",
"",
"LPTHE"
]
] | The MLLA single inclusive distribution inside one high energy (gluon) jet at small x is estimated by the steepest descent method. Its analytical expression is obtained outside the "limiting spectrum". It is then used to evaluate 2-particle correlations at the same level of generality. The dependence of both observables on the ratio between the infrared cutoff Q\_0 and Lambda\_QCD is studied. Fong & Webber's results for correlations are recovered at the limits when this ratio goes to 1 and when one stays close to the peak of the single inclusive distribution. |
1508.06131 | Shashank Bhatnagar Dr. | Hluf Negash and Shashank Bhatnagar | Spectroscopy of ground and excited states of pseudoscalar and vector
charmonium and bottomonium | 33 pages, 5 figure, 6 tables | Intl. J. Mod. Phys. E25, 1650059 (2016) | 10.1142/S0218301316500592 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we calculate the mass spectrum, weak decay constants, two photon
decay widths, and two gluon decay widths of ground (1S), and radially excited
(2S,3S,...) states of pseudoscalar charmoniuum and bottomonium such as
$\eta_{c}$ and $\eta_{b}$, as well as the mass spectrum and leptonic decay
constants of ground state (1S), excited (2S,1D,3S,2D,4S,and 3D) states of
vector charmonium and bottomonium such as $J/\psi$, and $\Upsilon$, using the
formulation of Bethe-Salpeter equation under covariant Instantaneous Ansatz
(CIA). Our results are in good agreement with data (where ever available) and
other models. In this framework, from the beginning, we employ a $4\times 4$
representation for two-body ($q\overline{q}$) BS amplitude for calculating both
the mass spectra as well as the transition amplitudes. However, the price we
have to pay is to solve a coupled set of equations for both pseudoscalar and
vector quarkonia, which we have explicitly shown get decoupled in the
heavy-quark approximation, leading to mass spectral equation with analytical
solutions for both masses, as well as eigenfunctions for all the above states,
in an approximate harmonic oscillator basis. Further, in the present framework
of BSE, the hadron-quark vertex function (and the full 4D BS wave function) for
pseudoscalar and vector quarkonia used for calculation of various processes,
accommodates all the Dirac structures from their complete set in a natural
manner.
| [
{
"created": "Tue, 25 Aug 2015 12:37:50 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Jan 2016 18:01:08 GMT",
"version": "v2"
},
{
"created": "Fri, 14 Oct 2016 08:39:47 GMT",
"version": "v3"
}
] | 2016-10-17 | [
[
"Negash",
"Hluf",
""
],
[
"Bhatnagar",
"Shashank",
""
]
] | In this work we calculate the mass spectrum, weak decay constants, two photon decay widths, and two gluon decay widths of ground (1S), and radially excited (2S,3S,...) states of pseudoscalar charmoniuum and bottomonium such as $\eta_{c}$ and $\eta_{b}$, as well as the mass spectrum and leptonic decay constants of ground state (1S), excited (2S,1D,3S,2D,4S,and 3D) states of vector charmonium and bottomonium such as $J/\psi$, and $\Upsilon$, using the formulation of Bethe-Salpeter equation under covariant Instantaneous Ansatz (CIA). Our results are in good agreement with data (where ever available) and other models. In this framework, from the beginning, we employ a $4\times 4$ representation for two-body ($q\overline{q}$) BS amplitude for calculating both the mass spectra as well as the transition amplitudes. However, the price we have to pay is to solve a coupled set of equations for both pseudoscalar and vector quarkonia, which we have explicitly shown get decoupled in the heavy-quark approximation, leading to mass spectral equation with analytical solutions for both masses, as well as eigenfunctions for all the above states, in an approximate harmonic oscillator basis. Further, in the present framework of BSE, the hadron-quark vertex function (and the full 4D BS wave function) for pseudoscalar and vector quarkonia used for calculation of various processes, accommodates all the Dirac structures from their complete set in a natural manner. |
1312.0051 | Farinaldo Queiroz | Chris Kelso, P.R.D. Pinheiro, Farinaldo S. Queiroz, William Shepherd | The Muon Anomalous Magnetic Moment in the Reduced Minimal 3-3-1 Model | 19 pages, 4 figures | Eur.Phys.J. C74 (2014) 2808 | 10.1140/epjc/s10052-014-2808-4 | CETUP2013-023 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the muon anomalous magnetic moment $(g-2)_{\mu}$ in the context of
the reduced minimal 3-3-1 model recently proposed in the literature. In
particular, its spectrum contains a doubly charged scalar ($H^{\pm \pm}$) and
gauge boson ($U^{\pm \pm}$), new singly charged vectors ($V^{\pm}$) and a
$Z^{\prime}$ boson, each of which might give a sizeable contribution to the
$(g-2)_{\mu}$. We compute the 1-loop contributions from all these new particles
to the $(g-2)_{\mu}$. We conclude that the doubly charged vector boson provides
the dominant contribution, and by comparing our results with the experimental
constraints we derive an expected value for the scale of $SU(3)_L\otimes
U(1)_N$ symmetry breaking $v_{\chi} \sim 2$ TeV. We also note that, if the
discrepancy in the anomalous moment is resolved in the future without this
model then the constraints will tighten to requiring $v_\chi > 2.7$ TeV with
current precision, and will entirely rule out the model if the expected
precision is achieved by the future experiment at Fermilab.
| [
{
"created": "Sat, 30 Nov 2013 02:45:37 GMT",
"version": "v1"
}
] | 2014-06-20 | [
[
"Kelso",
"Chris",
""
],
[
"Pinheiro",
"P. R. D.",
""
],
[
"Queiroz",
"Farinaldo S.",
""
],
[
"Shepherd",
"William",
""
]
] | We study the muon anomalous magnetic moment $(g-2)_{\mu}$ in the context of the reduced minimal 3-3-1 model recently proposed in the literature. In particular, its spectrum contains a doubly charged scalar ($H^{\pm \pm}$) and gauge boson ($U^{\pm \pm}$), new singly charged vectors ($V^{\pm}$) and a $Z^{\prime}$ boson, each of which might give a sizeable contribution to the $(g-2)_{\mu}$. We compute the 1-loop contributions from all these new particles to the $(g-2)_{\mu}$. We conclude that the doubly charged vector boson provides the dominant contribution, and by comparing our results with the experimental constraints we derive an expected value for the scale of $SU(3)_L\otimes U(1)_N$ symmetry breaking $v_{\chi} \sim 2$ TeV. We also note that, if the discrepancy in the anomalous moment is resolved in the future without this model then the constraints will tighten to requiring $v_\chi > 2.7$ TeV with current precision, and will entirely rule out the model if the expected precision is achieved by the future experiment at Fermilab. |
hep-ph/0608149 | Kopylov | A. Kopylov, V. Petukhov | On the Mass Eigenstate Composition of the 8B Neutrinos from the Sun | 13 pages, 1 figure, 1 table. Corrected version, published in
JCAP04(2007)002 | JCAP 0704:002,2007 | 10.1088/1475-7516/2007/04/002 | null | hep-ph | null | The present data of gallium experiments provide indirectly the only
experimental limit on the fraction of $\nu_2$ mass eigenstate for the $^8$B
neutrinos from the Sun. However, if to use the experimental data alone, the
fraction of $\nu_2$ and, consequently, $sin^2\theta_{sol}$ still is allowed to
be varied within a rather broad range. The further experimental efforts are
needed to clear this point.
| [
{
"created": "Mon, 14 Aug 2006 06:16:30 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Nov 2006 09:30:08 GMT",
"version": "v2"
},
{
"created": "Tue, 21 Nov 2006 10:17:06 GMT",
"version": "v3"
},
{
"created": "Thu, 19 Apr 2007 06:18:51 GMT",
"version": "v4"
}
] | 2010-10-27 | [
[
"Kopylov",
"A.",
""
],
[
"Petukhov",
"V.",
""
]
] | The present data of gallium experiments provide indirectly the only experimental limit on the fraction of $\nu_2$ mass eigenstate for the $^8$B neutrinos from the Sun. However, if to use the experimental data alone, the fraction of $\nu_2$ and, consequently, $sin^2\theta_{sol}$ still is allowed to be varied within a rather broad range. The further experimental efforts are needed to clear this point. |
2212.06509 | Francisco Albergaria | Francisco Albergaria, Lu\'is Lavoura, Jorge C. Rom\~ao | Oblique corrections from triplet quarks | 30 pages | JHEP 03, 031 (2023) | 10.1007/JHEP03(2023)031 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We present general formulas for the oblique-correction parameters $S$, $T$,
$U$, $V$, $W$, and $X$ in an extension of the Standard Model having arbitrary
numbers of singlet, doublet, and triplet quarks with electric charges $-4/3$,
$-1/3$, $2/3$, and $5/3$ that mix with the standard quarks of the same charge.
| [
{
"created": "Tue, 13 Dec 2022 11:47:41 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Dec 2022 17:17:13 GMT",
"version": "v2"
},
{
"created": "Mon, 6 Feb 2023 18:38:13 GMT",
"version": "v3"
},
{
"created": "Mon, 20 Feb 2023 12:41:55 GMT",
"version": "v4"
},
{
"cr... | 2023-03-13 | [
[
"Albergaria",
"Francisco",
""
],
[
"Lavoura",
"Luís",
""
],
[
"Romão",
"Jorge C.",
""
]
] | We present general formulas for the oblique-correction parameters $S$, $T$, $U$, $V$, $W$, and $X$ in an extension of the Standard Model having arbitrary numbers of singlet, doublet, and triplet quarks with electric charges $-4/3$, $-1/3$, $2/3$, and $5/3$ that mix with the standard quarks of the same charge. |
hep-ph/0101036 | Akihiro Nakamura | Shigenori Kagiyama, Akira Minaka, Akihiro Nakamura (Kagoshima Univ.) | Evolution of the quark-gluon and hadronic fluid with the compressible
bag model | 20+1 pages, LaTeX2e, 12 figures | null | null | Kagoshima HE-01-1 | hep-ph | null | The evolution of matter produced in nucleus collisions is investigated in the
frame work of the simplified fluid equation, where the compressible bag model
is used as the equation of state for hadrons. It is shown that the quark-gluon
phase is easily achieved in RHIC experiments, and that the typical structure of
the phase transition, however, may be difficult to observe in simple analyses
of $<p_t>$ data.
| [
{
"created": "Thu, 4 Jan 2001 12:56:42 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kagiyama",
"Shigenori",
"",
"Kagoshima Univ."
],
[
"Minaka",
"Akira",
"",
"Kagoshima Univ."
],
[
"Nakamura",
"Akihiro",
"",
"Kagoshima Univ."
]
] | The evolution of matter produced in nucleus collisions is investigated in the frame work of the simplified fluid equation, where the compressible bag model is used as the equation of state for hadrons. It is shown that the quark-gluon phase is easily achieved in RHIC experiments, and that the typical structure of the phase transition, however, may be difficult to observe in simple analyses of $<p_t>$ data. |
1501.02020 | Li-Gang Jin | Li-Gang Jin, Rui Tang, and Fei Zhang | A three-loop radiative neutrino mass model with dark matter | 7 pages, 3 figures | Phys. Lett. B 741 (2015) 163 | 10.1016/j.physletb.2014.12.034 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a model that generates small neutrino masses at three-loop level
due to the existence of Majorana fermionic dark matter, which is stabilized by
a Z2 symmetry. The model predicts that the lightest neutrino is massless. We
show a prototypical parameter choice allowed by relevant experimental data,
which favors the case of normal neutrino mass spectrum and the dark matter with
m \sim 50-135 GeV and a sizable Yukawa coupling. It means that new particles
can be searched for in future e+e- collisions.
| [
{
"created": "Fri, 9 Jan 2015 02:46:39 GMT",
"version": "v1"
}
] | 2018-05-09 | [
[
"Jin",
"Li-Gang",
""
],
[
"Tang",
"Rui",
""
],
[
"Zhang",
"Fei",
""
]
] | We present a model that generates small neutrino masses at three-loop level due to the existence of Majorana fermionic dark matter, which is stabilized by a Z2 symmetry. The model predicts that the lightest neutrino is massless. We show a prototypical parameter choice allowed by relevant experimental data, which favors the case of normal neutrino mass spectrum and the dark matter with m \sim 50-135 GeV and a sizable Yukawa coupling. It means that new particles can be searched for in future e+e- collisions. |
0708.0647 | Douglas Gingrich Mr. | Douglas M. Gingrich and Kevin Martell | Microcanonical treatment of black hole decay at the Large Hadron
Collider | small additions and clarifications, format for J. Phys. G | J. Phys. G: Nucl. Part. Phys. 35 (2008) 035001 | 10.1088/0954-3899/35/3/035001 | null | hep-ph | null | This study of corrections to the canonical picture of black hole decay in
large extra dimensions examines the effects of back-reaction corrected and
microcanonical emission at the LHC. We provide statistical interpretations of
the different multiparticle number densities in terms of black hole decay to
standard model particles. Provided new heavy particles of mass near the
fundamental Planck scale are not discovered, differences between these
corrections and thermal decay will be insignificant at the LHC.
| [
{
"created": "Sat, 4 Aug 2007 21:23:35 GMT",
"version": "v1"
},
{
"created": "Sat, 15 Sep 2007 16:32:20 GMT",
"version": "v2"
},
{
"created": "Mon, 24 Dec 2007 03:58:27 GMT",
"version": "v3"
}
] | 2009-11-13 | [
[
"Gingrich",
"Douglas M.",
""
],
[
"Martell",
"Kevin",
""
]
] | This study of corrections to the canonical picture of black hole decay in large extra dimensions examines the effects of back-reaction corrected and microcanonical emission at the LHC. We provide statistical interpretations of the different multiparticle number densities in terms of black hole decay to standard model particles. Provided new heavy particles of mass near the fundamental Planck scale are not discovered, differences between these corrections and thermal decay will be insignificant at the LHC. |
hep-ph/9409275 | David Spergel | Glenn D. Starkman (CITA) and David N. Spergel (Princeton) | A New Technique for Detecting Supersymmetric Dark Matter | 6 pages plain tex | null | 10.1103/PhysRevLett.74.2623 | null | hep-ph astro-ph | null | We estimate the event rate for excitation of atomic transition by
photino-like dark matter. For excitations of several eV, this event rate can
exceed naive cross-section by many orders of magnitude. Although the event rate
for these atomic excitation is smaller than that of nuclear recoil off of
non-zero spin nuclei, the photons emitted by the deexcitation are easier to
detect than low-energy nuclear recoils. For many elements, there are several
low-lying states with comparable excitation rates, thus, spectral ratios could
be used to distinguish signal from background.
| [
{
"created": "Fri, 9 Sep 1994 21:20:31 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Sep 1994 13:16:16 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Starkman",
"Glenn D.",
"",
"CITA"
],
[
"Spergel",
"David N.",
"",
"Princeton"
]
] | We estimate the event rate for excitation of atomic transition by photino-like dark matter. For excitations of several eV, this event rate can exceed naive cross-section by many orders of magnitude. Although the event rate for these atomic excitation is smaller than that of nuclear recoil off of non-zero spin nuclei, the photons emitted by the deexcitation are easier to detect than low-energy nuclear recoils. For many elements, there are several low-lying states with comparable excitation rates, thus, spectral ratios could be used to distinguish signal from background. |
1106.2741 | Alexei P. Martynenko | A.P. Martynenko (Samara State U. and Samara State Aerospace U.), A.M.
Trunin (Samara State Aerospace U.) | Relativistic description of the double P-wave charmonium production in
e^+e^- annihilation | 15 pages, 1 figure | null | null | SSU-HEP-11/05 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | On the basis of perturbative QCD and the relativistic quark model we
calculate relativistic and bound state corrections in the production processes
of a pair of P-wave charmonium states. Relativistic factors in the production
amplitude connected with the relative motion of heavy quarks and the
transformation law of the bound state wave function to the reference frame of
the moving P-wave mesons are taken into account. For the gluon and quark
propagators entering the production vertex function we use a truncated
expansion in the ratio of the relative quark momenta to the center-of-mass
energy sqrt{s} up to the second order. Relativistic corrections to the quark
bound state wave functions in the rest frame are considered by means of the
Breit-like potential. It turns out that the examined effects change essentially
the nonrelativistic results of the cross section for the reaction e^++e^-\to
h_c+\chi_{cJ} at the center-of-mass energy sqrt{s}=10.6 GeV.
| [
{
"created": "Tue, 14 Jun 2011 15:23:22 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Jun 2011 12:57:51 GMT",
"version": "v2"
},
{
"created": "Wed, 10 Aug 2011 11:13:28 GMT",
"version": "v3"
}
] | 2011-08-11 | [
[
"Martynenko",
"A. P.",
"",
"Samara State U. and Samara State Aerospace U."
],
[
"Trunin",
"A. M.",
"",
"Samara State Aerospace U."
]
] | On the basis of perturbative QCD and the relativistic quark model we calculate relativistic and bound state corrections in the production processes of a pair of P-wave charmonium states. Relativistic factors in the production amplitude connected with the relative motion of heavy quarks and the transformation law of the bound state wave function to the reference frame of the moving P-wave mesons are taken into account. For the gluon and quark propagators entering the production vertex function we use a truncated expansion in the ratio of the relative quark momenta to the center-of-mass energy sqrt{s} up to the second order. Relativistic corrections to the quark bound state wave functions in the rest frame are considered by means of the Breit-like potential. It turns out that the examined effects change essentially the nonrelativistic results of the cross section for the reaction e^++e^-\to h_c+\chi_{cJ} at the center-of-mass energy sqrt{s}=10.6 GeV. |
2304.11573 | Saurabh D. Rindani | Kumar Rao, Saurabh D. Rindani, Priyanka Sarmah and Balbeer Singh | Polarized $Z$ cross sections in Higgsstrahlung for the determination of
anomalous $ZZH$ couplings | This is a shorter version of arXiv:2202.10215v1. This shorter version
is published in Phys. Lett. B | Phys. Lett. B 840 (2023) 137847 | 10.1016/j.physletb.2023.137847 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The production of a Higgs boson in association with a $Z$ at an
electron-positron collider is one of the cleanest methods for the measurement
of the couplings of the Higgs boson. In view of the large production cross
section at energies a little above the threshold, it seems feasible to make a
more detailed study of the process by measuring the cross sections for
polarized $Z$ in order to measure possible anomalous $ZZH$ couplings. We show
that certain combinations of cross sections in $e^+e^- \to ZH$ with different
$Z$ polarizations help to enhance or isolate the effect of one of the two kinds
of anomalous $ZZH$ couplings possible on general grounds of CP and Lorentz
invariance. These combinations can be useful to get information on the $ZZH$
coupling in the specific contexts of an effective field theory,
two-Higgs-doublet models, and composite Higgs models, in a relatively
model-independent fashion. We find in particular that the longitudinal helicity
fraction of the $Z$ is expected to be insensitive to anomalous couplings, and
would be close to its value in the standard model in the scenarios we consider.
We also discuss the sensitivity of the proposed measurements to the anomalous
couplings, including longitudinal beam polarizations, which suppress
backgrounds, and can improve the sensitivity if appropriately chosen.
| [
{
"created": "Sun, 23 Apr 2023 08:10:26 GMT",
"version": "v1"
}
] | 2023-04-28 | [
[
"Rao",
"Kumar",
""
],
[
"Rindani",
"Saurabh D.",
""
],
[
"Sarmah",
"Priyanka",
""
],
[
"Singh",
"Balbeer",
""
]
] | The production of a Higgs boson in association with a $Z$ at an electron-positron collider is one of the cleanest methods for the measurement of the couplings of the Higgs boson. In view of the large production cross section at energies a little above the threshold, it seems feasible to make a more detailed study of the process by measuring the cross sections for polarized $Z$ in order to measure possible anomalous $ZZH$ couplings. We show that certain combinations of cross sections in $e^+e^- \to ZH$ with different $Z$ polarizations help to enhance or isolate the effect of one of the two kinds of anomalous $ZZH$ couplings possible on general grounds of CP and Lorentz invariance. These combinations can be useful to get information on the $ZZH$ coupling in the specific contexts of an effective field theory, two-Higgs-doublet models, and composite Higgs models, in a relatively model-independent fashion. We find in particular that the longitudinal helicity fraction of the $Z$ is expected to be insensitive to anomalous couplings, and would be close to its value in the standard model in the scenarios we consider. We also discuss the sensitivity of the proposed measurements to the anomalous couplings, including longitudinal beam polarizations, which suppress backgrounds, and can improve the sensitivity if appropriately chosen. |
hep-ph/9803348 | Eric C. Martell | David Bowser-Chao, Tom D. Imbo, B. Alex King and Eric C. Martell | Lepto-mesons, Leptoquarkonium and the QCD Potential | 12 pages, 1 figure, 3 tables, plain TeX, requires harvmac. References
updated and minor clarifications made. To appear in Physics Letters B | Phys.Lett. B432 (1998) 167-174 | 10.1016/S0370-2693(98)00636-4 | UICHEP-TH/97-13 | hep-ph hep-ex | null | We consider bound states of heavy leptoquark-antiquark pairs (lepto-mesons)
as well as leptoquark-antileptoquark pairs (leptoquarkonium). Unlike the
situation for top quarks, leptoquarks (if they exist) may live long enough for
these hadrons to form. We study the spectra and decay widths of these states in
the context of a nonrelativistic potential model which matches the recently
calculated two-loop QCD potential at short distances to a successful
phenomenological quarkonium potential at intermediate distances. We also
compute the expected number of events for these states at future colliders.
| [
{
"created": "Sat, 14 Mar 1998 00:15:41 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Mar 1998 19:29:22 GMT",
"version": "v2"
},
{
"created": "Thu, 19 Mar 1998 17:10:58 GMT",
"version": "v3"
},
{
"created": "Mon, 18 May 1998 20:34:41 GMT",
"version": "v4"
}
] | 2009-10-31 | [
[
"Bowser-Chao",
"David",
""
],
[
"Imbo",
"Tom D.",
""
],
[
"King",
"B. Alex",
""
],
[
"Martell",
"Eric C.",
""
]
] | We consider bound states of heavy leptoquark-antiquark pairs (lepto-mesons) as well as leptoquark-antileptoquark pairs (leptoquarkonium). Unlike the situation for top quarks, leptoquarks (if they exist) may live long enough for these hadrons to form. We study the spectra and decay widths of these states in the context of a nonrelativistic potential model which matches the recently calculated two-loop QCD potential at short distances to a successful phenomenological quarkonium potential at intermediate distances. We also compute the expected number of events for these states at future colliders. |
0711.1075 | Olga Mena Requejo | Andreas Jansson, Olga Mena, Stephen Parke and Niki Saoulidou | Combining CPT-conjugate Neutrino channels at Fermilab | 21 pages, 9 figures | Phys.Rev.D78:053002,2008 | 10.1103/PhysRevD.78.053002 | FERMILAB-PUB-07-456-APC-E-T, ROMA-TH-1458 | hep-ph | null | We explore an alternative strategy to determine the neutrino mass hierarchy
by making use of possible future neutrino facilities at Fermilab. Here, we use
CPT-conjugate neutrino channels, exploiting a nu_mu beam from the NuMI beamline
and a barnu_e beam from a betabeam experimental setup. Both experiments are
performed at approximately the same E/L. We present different possible
accelerator scenarios for the betabeam neutrino setup and fluxes. This
CPT-conjugate neutrino channel scenario can extract the neutrino mass hierarchy
down to sin^2 (2 theta_13) \approx 0.02.
| [
{
"created": "Wed, 7 Nov 2007 13:12:14 GMT",
"version": "v1"
}
] | 2008-12-18 | [
[
"Jansson",
"Andreas",
""
],
[
"Mena",
"Olga",
""
],
[
"Parke",
"Stephen",
""
],
[
"Saoulidou",
"Niki",
""
]
] | We explore an alternative strategy to determine the neutrino mass hierarchy by making use of possible future neutrino facilities at Fermilab. Here, we use CPT-conjugate neutrino channels, exploiting a nu_mu beam from the NuMI beamline and a barnu_e beam from a betabeam experimental setup. Both experiments are performed at approximately the same E/L. We present different possible accelerator scenarios for the betabeam neutrino setup and fluxes. This CPT-conjugate neutrino channel scenario can extract the neutrino mass hierarchy down to sin^2 (2 theta_13) \approx 0.02. |
1206.2632 | Peter Schweitzer | Manuel Mai, Peter Schweitzer | Energy momentum tensor, stability, and the D-term of Q-balls | 18 pages, 12 figures | Phys. Rev. D 86, 076001 (2012) | 10.1103/PhysRevD.86.076001 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the energy-momentum tensor of stable, meta-stable and unstable
Q-balls in scalar field theories with U(1) symmetry. We calculate properties
such as charge, mass, mean square radii and the constant d1 ("D-term") as
functions of the phase space angular velocity omega. We discuss the limits when
omega approaches the boundaries of the region in which solutions exist, and
derive analytical results for the quantities in these limits. The central
result of this work is the rigorous proof that d1 is strictly negative for all
finite energy solutions in the Q-ball system. We also show that for Q-balls
stability is a sufficient, but not necessary, condition for d1 to be negative.
| [
{
"created": "Tue, 12 Jun 2012 19:48:40 GMT",
"version": "v1"
}
] | 2012-10-03 | [
[
"Mai",
"Manuel",
""
],
[
"Schweitzer",
"Peter",
""
]
] | We study the energy-momentum tensor of stable, meta-stable and unstable Q-balls in scalar field theories with U(1) symmetry. We calculate properties such as charge, mass, mean square radii and the constant d1 ("D-term") as functions of the phase space angular velocity omega. We discuss the limits when omega approaches the boundaries of the region in which solutions exist, and derive analytical results for the quantities in these limits. The central result of this work is the rigorous proof that d1 is strictly negative for all finite energy solutions in the Q-ball system. We also show that for Q-balls stability is a sufficient, but not necessary, condition for d1 to be negative. |
hep-ph/9608407 | Andrzej Czarnecki | Andrzej Czarnecki and Vladimir A. Smirnov | Threshold behavior of Feynman diagrams: the master two-loop propagator | Minor additions; to appear in Physics Letters B | Phys.Lett. B394 (1997) 211-217 | 10.1016/S0370-2693(96)01698-X | TTP96-32 | hep-ph | null | An asymptotic expansion of the two-loop two-point ``master'' diagram with two
masses $m$ and $M$, on the mass shell $Q^2=M^2$, is presented. The treatment of
the non-analytical terms arising in the expansion around the branching point is
discussed. Some details of the calculation of a new class of two-loop integrals
are given.
| [
{
"created": "Thu, 22 Aug 1996 10:38:34 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Jan 1997 16:22:29 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Czarnecki",
"Andrzej",
""
],
[
"Smirnov",
"Vladimir A.",
""
]
] | An asymptotic expansion of the two-loop two-point ``master'' diagram with two masses $m$ and $M$, on the mass shell $Q^2=M^2$, is presented. The treatment of the non-analytical terms arising in the expansion around the branching point is discussed. Some details of the calculation of a new class of two-loop integrals are given. |
0711.0448 | Arman Esmaili | Arman Esmaili and Yasaman Farzan | A new class of invariants in the lepton sector | 19 pages, Version appeared in Nuclear Physics B | Nucl.Phys.B811:98-108,2009 | 10.1016/j.nuclphysb.2008.11.013 | IPM/P-2007/067 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a new set of combinations from the mass matrices of the charged
leptons and neutrinos that are invariant under basis transformation, hereafter
{\it the} invariants. We use these invariants to study various symmetries and
neutrino mass textures in a basis independent way. In particular, we show that
by using these invariants the ansatz such as $\mu-\tau$ exchange and reflection
symmetries, various texture zeros and flavor symmetries can be expressed in a
general basis.
| [
{
"created": "Sat, 3 Nov 2007 14:00:02 GMT",
"version": "v1"
},
{
"created": "Sun, 18 Jan 2009 12:15:26 GMT",
"version": "v2"
}
] | 2009-02-02 | [
[
"Esmaili",
"Arman",
""
],
[
"Farzan",
"Yasaman",
""
]
] | We construct a new set of combinations from the mass matrices of the charged leptons and neutrinos that are invariant under basis transformation, hereafter {\it the} invariants. We use these invariants to study various symmetries and neutrino mass textures in a basis independent way. In particular, we show that by using these invariants the ansatz such as $\mu-\tau$ exchange and reflection symmetries, various texture zeros and flavor symmetries can be expressed in a general basis. |
hep-ph/0506230 | Matteo Beccaria | M. Beccaria, F.M. Renard, and C. Verzegnassi | Weak Interaction Sum Rules for Polarized top-antitop Production at LHC | 13 pages, 3 figures, local report number added | Phys.Rev.D72:093001,2005 | 10.1103/PhysRevD.72.093001 | PM/05-20 | hep-ph | null | We consider two polarization asymmetries in the process of top-antitop
production at LHC. We show that the theoretical predictions for these two
quantities, at the strong and electroweak partonic one-loop level, are free of
QCD and QED effects. At this perturbative level we derive two sum rules, that
relate measurable quantities of top-antitop production to genuinely weak
inputs. This would allow to perform two independent tests of the candidate
theoretical model, with a precision that will be fixed by the future
experimental accuracies of the different polarization measurements. A tentative
quantitative illustration of this statement for a specific MSSM scenario is
enclosed, and a generalization to include two other future realistic
measurements is also proposed.
| [
{
"created": "Thu, 23 Jun 2005 11:37:11 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Jun 2005 10:02:28 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Beccaria",
"M.",
""
],
[
"Renard",
"F. M.",
""
],
[
"Verzegnassi",
"C.",
""
]
] | We consider two polarization asymmetries in the process of top-antitop production at LHC. We show that the theoretical predictions for these two quantities, at the strong and electroweak partonic one-loop level, are free of QCD and QED effects. At this perturbative level we derive two sum rules, that relate measurable quantities of top-antitop production to genuinely weak inputs. This would allow to perform two independent tests of the candidate theoretical model, with a precision that will be fixed by the future experimental accuracies of the different polarization measurements. A tentative quantitative illustration of this statement for a specific MSSM scenario is enclosed, and a generalization to include two other future realistic measurements is also proposed. |
hep-ph/0207300 | Fridger Schrempp | F. Schrempp (DESY) and A. Utermann (DESY) | QCD Instantons and High-Energy Diffractive Scattering | 13 pages, 2 figures, typos corrected, comments added; version as
submitted to and appearing in Phys. Lett. B | Phys.Lett. B543 (2002) 197-207 | 10.1016/S0370-2693(02)02458-9 | DESY 02-094 | hep-ph | null | We pursue the intriguing possibility that larger-size instantons build up
diffractive scattering, with the marked instanton-size scale <rho>
approximately 0.5 fm being reflected in the conspicuous ``geometrization'' of
soft QCD. As an explicit step in this direction, the known instanton-induced
cross sections in deep-inelastic scattering (DIS) are transformed into the
familiar colour dipole picture, which represents an intuitive framework for
investigating the transition from hard to soft physics in DIS at small x_{Bj}.
The simplest instanton (I) process without final-state gluons is studied first.
With the help of lattice results, the q bar{q}-dipole size r is carefully
increased towards hadronic dimensions. Unlike perturbative QCD, one now
observes a competition between two crucial length scales: the dipole size r and
the size rho of the background instanton that is sharply localized around <rho>
approximately 0.5 fm. For r exceeding <rho>, the dipole cross section indeed
saturates towards a geometrical limit, proportional to the area pi <rho>^2,
subtended by the instanton. In case of final-state gluons, lattice data are
crucially used to support the emerging picture and to assert the range of
validity of the underlying I bar{I}-valley approach. As function of an
appropriate energy variable, the resulting dipole cross section turns out to be
sharply peaked at the sphaleron mass in the soft regime. The general
geometrical features remain like in the case without gluons.
| [
{
"created": "Wed, 24 Jul 2002 19:21:48 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Aug 2002 16:00:55 GMT",
"version": "v2"
}
] | 2010-04-05 | [
[
"Schrempp",
"F.",
"",
"DESY"
],
[
"Utermann",
"A.",
"",
"DESY"
]
] | We pursue the intriguing possibility that larger-size instantons build up diffractive scattering, with the marked instanton-size scale <rho> approximately 0.5 fm being reflected in the conspicuous ``geometrization'' of soft QCD. As an explicit step in this direction, the known instanton-induced cross sections in deep-inelastic scattering (DIS) are transformed into the familiar colour dipole picture, which represents an intuitive framework for investigating the transition from hard to soft physics in DIS at small x_{Bj}. The simplest instanton (I) process without final-state gluons is studied first. With the help of lattice results, the q bar{q}-dipole size r is carefully increased towards hadronic dimensions. Unlike perturbative QCD, one now observes a competition between two crucial length scales: the dipole size r and the size rho of the background instanton that is sharply localized around <rho> approximately 0.5 fm. For r exceeding <rho>, the dipole cross section indeed saturates towards a geometrical limit, proportional to the area pi <rho>^2, subtended by the instanton. In case of final-state gluons, lattice data are crucially used to support the emerging picture and to assert the range of validity of the underlying I bar{I}-valley approach. As function of an appropriate energy variable, the resulting dipole cross section turns out to be sharply peaked at the sphaleron mass in the soft regime. The general geometrical features remain like in the case without gluons. |
1801.04760 | Matteo Rinaldi | Matteo Rinaldi and Federico Alberto Ceccopieri | Hadronic structure from double parton scattering | 5 pages, 1 figure. References added and figure updated. Referee
suggestions implemented. Published in PRD rapid communication | Phys. Rev. D 97, 071501 (2018) | 10.1103/PhysRevD.97.071501 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the present paper we consider the so-called effective cross section, a
quantity which encodes the experimental knowledge on double parton scattering
in hadronic collisions that has been accomulated so far. We show that the
effective cross section, under some assumptions close to those adopted in its
experimental extractions, can be used to obtain a range of mean transverse
distance between an interacting parton pair in double parton scattering.
Therefore we have proved that the effective cross section offers a way to
access information on the hadronic structure.
| [
{
"created": "Mon, 15 Jan 2018 12:01:13 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Jan 2018 13:38:50 GMT",
"version": "v2"
},
{
"created": "Mon, 30 Apr 2018 13:45:42 GMT",
"version": "v3"
}
] | 2018-05-02 | [
[
"Rinaldi",
"Matteo",
""
],
[
"Ceccopieri",
"Federico Alberto",
""
]
] | In the present paper we consider the so-called effective cross section, a quantity which encodes the experimental knowledge on double parton scattering in hadronic collisions that has been accomulated so far. We show that the effective cross section, under some assumptions close to those adopted in its experimental extractions, can be used to obtain a range of mean transverse distance between an interacting parton pair in double parton scattering. Therefore we have proved that the effective cross section offers a way to access information on the hadronic structure. |
0711.0161 | Guido Altarelli | Guido Altarelli | Lectures on Models of Neutrino Masses and Mixings | Two lectures given at the Summer Institute 2007, 3-10 August 2007,
Fuji-Yoshida, Japan 27 pages, 3 figures | null | null | RM3-TH/07-17, CERN-PH-TH/2007-213 | hep-ph | null | We present a concise review of models for neutrino masses and mixings with
particular emphasis on recent developments and current problems. We discuss in
detail attempts at reproducing approximate tri-bimaximal mixing starting from
discrete symmetry groups, notably A4. We discuss the problems encountered when
trying to extend the symmetry to the quark sector and to construct Grand
Unified versions.
| [
{
"created": "Thu, 1 Nov 2007 16:54:45 GMT",
"version": "v1"
}
] | 2007-11-02 | [
[
"Altarelli",
"Guido",
""
]
] | We present a concise review of models for neutrino masses and mixings with particular emphasis on recent developments and current problems. We discuss in detail attempts at reproducing approximate tri-bimaximal mixing starting from discrete symmetry groups, notably A4. We discuss the problems encountered when trying to extend the symmetry to the quark sector and to construct Grand Unified versions. |
2103.10217 | Sergei Chekanov V. | S.V. Chekanov and S. Darmora and W. Islam and C.E.M. Wagner and J.
Zhang | Model-independent searches for new physics in multi-body invariant
masses | 17 pages, 10 figures, contribution to Snowmass 2021 | Universe, Volume 7, Issue 9 (2021) | 10.3390/universe7090333 | ANL-HEP-166648 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Model-independent searches for physics beyond the Standard Model typically
focus on invariant masses of two objects (jets, leptons or photons). In this
study we explore opportunities for similar model-agnostic searches in
multi-body invariant masses. In particular, we focus on the situations when new
physics can be observed in a model-independent way in three- and four-body
invariant masses of jets and leptons. Such searches may have good prospects in
finding new physics in the situations when two-body invariant masses, that have
been extensively explored at collider experiments in the past, cannot provide
sufficient signatures for experimental observations.
| [
{
"created": "Thu, 18 Mar 2021 12:41:53 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Sep 2021 16:30:12 GMT",
"version": "v2"
}
] | 2021-09-09 | [
[
"Chekanov",
"S. V.",
""
],
[
"Darmora",
"S.",
""
],
[
"Islam",
"W.",
""
],
[
"Wagner",
"C. E. M.",
""
],
[
"Zhang",
"J.",
""
]
] | Model-independent searches for physics beyond the Standard Model typically focus on invariant masses of two objects (jets, leptons or photons). In this study we explore opportunities for similar model-agnostic searches in multi-body invariant masses. In particular, we focus on the situations when new physics can be observed in a model-independent way in three- and four-body invariant masses of jets and leptons. Such searches may have good prospects in finding new physics in the situations when two-body invariant masses, that have been extensively explored at collider experiments in the past, cannot provide sufficient signatures for experimental observations. |
2310.03680 | Silvano Simula | G. Martinelli, S. Simula and L. Vittorio | Updates on the determination of $\vert V_{cb} \vert$, $R(D^{*})$ and
$\vert V_{ub} \vert/\vert V_{cb} \vert$ | 28 pages, 9 figures, 6 tables. Recent update of the HPQCD results for
the semileptonic $B \to D^*$ form factors included in the lattice inputs for
the bin-per-bin analyses. Figs. 1-2,4,6-8 and Tables 1-4 updated. Main
conclusions unchanged. Covariance matrices for various theoretical
observables added as appendix for applications to phenomenological studies | null | null | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an updated determination of the values of $\vert V_{cb} \vert$,
$R(D^*)$ and $\vert V_{ub} \vert/\vert V_{cb} \vert$ based on the new data on
semileptonic $B \to D^* \ell \nu_\ell$ decays by the Belle and Belle-II
Collaborations and on the recent theoretical progress in the calculation of the
form factors relevant for semileptonic $B \to D^* \ell \nu_\ell$ and $B_s \to K
\ell \nu_\ell$ decays. In particular we present results derived by applying
either the Dispersive Matrix (DM) method of Refs. [1-6] or the more standard
Boyd-Grinstein-Lebed (BGL) [7] approach to the most recent values of the form
factors determined in lattice QCD. Using all the available lattice results for
the form factors from the DM method we get the theoretical value $R^{\rm
th}(D^*) = 0.262 \pm 0.009$ and we extract from a bin-per-bin analysis of the
experimental data the value $\vert V_{cb} \vert = (39.92 \pm 0.64)
\cdot10^{-3}$. Our result for $R(D^*)$ is consistent with the latest
experimental world average $R^{\rm exp}(D^*) = 0.284 \pm 0.012$ [8]} at the
$\simeq 1.5\,\sigma$ level. Our value for $\vert V_{cb} \vert$ is compatible
with the latest inclusive determinations $\vert V_{cb} \vert^{\rm incl} =
(41.97 \pm 0.48) \cdot 10^{-3}$ [9] and $\vert V_{cb} \vert^{\rm incl} =
(41.69\pm 0.63) \cdot 10^{-3}$ [10] within $\simeq 2.6$ and $\simeq 2.0$
standard deviations, respectively. From a reappraisal of the calculations of
$\vert V_{ub} \vert / \vert V_{cb} \vert$, we also obtain $\vert V_{ub} \vert /
\vert V_{cb} \vert = 0.087\pm 0.009$ in good agreement with the result $\vert
V_{ub} \vert / \vert V_{cb} \vert = 0.0844\pm 0.0056$ from the latest FLAG
review [11].
| [
{
"created": "Thu, 5 Oct 2023 16:58:47 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Nov 2023 13:49:27 GMT",
"version": "v2"
},
{
"created": "Mon, 25 Mar 2024 10:35:42 GMT",
"version": "v3"
}
] | 2024-03-26 | [
[
"Martinelli",
"G.",
""
],
[
"Simula",
"S.",
""
],
[
"Vittorio",
"L.",
""
]
] | We present an updated determination of the values of $\vert V_{cb} \vert$, $R(D^*)$ and $\vert V_{ub} \vert/\vert V_{cb} \vert$ based on the new data on semileptonic $B \to D^* \ell \nu_\ell$ decays by the Belle and Belle-II Collaborations and on the recent theoretical progress in the calculation of the form factors relevant for semileptonic $B \to D^* \ell \nu_\ell$ and $B_s \to K \ell \nu_\ell$ decays. In particular we present results derived by applying either the Dispersive Matrix (DM) method of Refs. [1-6] or the more standard Boyd-Grinstein-Lebed (BGL) [7] approach to the most recent values of the form factors determined in lattice QCD. Using all the available lattice results for the form factors from the DM method we get the theoretical value $R^{\rm th}(D^*) = 0.262 \pm 0.009$ and we extract from a bin-per-bin analysis of the experimental data the value $\vert V_{cb} \vert = (39.92 \pm 0.64) \cdot10^{-3}$. Our result for $R(D^*)$ is consistent with the latest experimental world average $R^{\rm exp}(D^*) = 0.284 \pm 0.012$ [8]} at the $\simeq 1.5\,\sigma$ level. Our value for $\vert V_{cb} \vert$ is compatible with the latest inclusive determinations $\vert V_{cb} \vert^{\rm incl} = (41.97 \pm 0.48) \cdot 10^{-3}$ [9] and $\vert V_{cb} \vert^{\rm incl} = (41.69\pm 0.63) \cdot 10^{-3}$ [10] within $\simeq 2.6$ and $\simeq 2.0$ standard deviations, respectively. From a reappraisal of the calculations of $\vert V_{ub} \vert / \vert V_{cb} \vert$, we also obtain $\vert V_{ub} \vert / \vert V_{cb} \vert = 0.087\pm 0.009$ in good agreement with the result $\vert V_{ub} \vert / \vert V_{cb} \vert = 0.0844\pm 0.0056$ from the latest FLAG review [11]. |
hep-ph/0212102 | Valery G. Serbo | G.L. Kotkin, V.G. Serbo (Novosibirsk State University, Russia) | Once Again about Beam-Size or MD-Effect at Colliding Beams | 16 Latex page | null | null | null | hep-ph | null | For several processes at colliding beams, macroscopically large impact
parameters give an essential contribution to the standard cross section. These
impact parameters may be much larger than the transverse sizes of the colliding
bunches. In that case, the standard calculations have to be essentially modify.
The corresponding formulae were given twenty years ago. In recent paper of
Baier and Katkov [17] it was claimed that the previous results about
bremsstrahlung spectrum have to be revised and an additional subtraction
related to the coherent contribution has to be done. This additional term has
been calculated with the result that it may be essential for the performed and
future experiments. In the present paper we analyze in detail the coherent and
incoherent contributions in the conditions, considered in paper [17]. In
contract to above claims, we found out that under these conditions the coherent
contribution is completely negligible and, therefore, there is no need to
revise the previous results.
| [
{
"created": "Fri, 6 Dec 2002 13:54:27 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kotkin",
"G. L.",
"",
"Novosibirsk State University, Russia"
],
[
"Serbo",
"V. G.",
"",
"Novosibirsk State University, Russia"
]
] | For several processes at colliding beams, macroscopically large impact parameters give an essential contribution to the standard cross section. These impact parameters may be much larger than the transverse sizes of the colliding bunches. In that case, the standard calculations have to be essentially modify. The corresponding formulae were given twenty years ago. In recent paper of Baier and Katkov [17] it was claimed that the previous results about bremsstrahlung spectrum have to be revised and an additional subtraction related to the coherent contribution has to be done. This additional term has been calculated with the result that it may be essential for the performed and future experiments. In the present paper we analyze in detail the coherent and incoherent contributions in the conditions, considered in paper [17]. In contract to above claims, we found out that under these conditions the coherent contribution is completely negligible and, therefore, there is no need to revise the previous results. |
hep-ph/9907416 | Stefan Scherer | S. Scherer (Institut f. Kernphysik, Mainz, Germany) | Generalized dipole polarizabilities of the pion | 11 pages, Latex2e, 5 postscript figures, uses ws-p8-50x6-00.cls,
invited talk at the 2nd International Conference on Perspectives in Hadronic
Physics, 10 - 14 May 1999, Trieste, Italy | null | null | MKPH-T-99-19 | hep-ph hep-ex nucl-th | null | We discuss the virtual Compton scattering amplitude $\gamma^\ast+\pi\to
\gamma+\pi$ which enters the reaction $\pi^-+e^-\to\pi^-+e^-+\gamma$. The
low-energy scattering amplitude is divided into a model-independent part,
involving only the electromagnetic form factor, and a residual part which
contains structure information related specifically to (virtual) Compton
scattering. In the limit of vanishing final-photon energy, the residual
amplitude can be expressed in terms of three generalized dipole
polarizabilities which are functions of the squared virtual-photon
four-momentum. We study the VCS amplitude in the framework of chiral
perturbation theory at ${\cal O}(p^4)$. At the one-loop level the generalized
dipole polarizabilities are degenerate
$\alpha_L(q^2)=\alpha_T(q^2)=-\beta(q^2)$.
| [
{
"created": "Mon, 19 Jul 1999 16:26:43 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Scherer",
"S.",
"",
"Institut f. Kernphysik, Mainz, Germany"
]
] | We discuss the virtual Compton scattering amplitude $\gamma^\ast+\pi\to \gamma+\pi$ which enters the reaction $\pi^-+e^-\to\pi^-+e^-+\gamma$. The low-energy scattering amplitude is divided into a model-independent part, involving only the electromagnetic form factor, and a residual part which contains structure information related specifically to (virtual) Compton scattering. In the limit of vanishing final-photon energy, the residual amplitude can be expressed in terms of three generalized dipole polarizabilities which are functions of the squared virtual-photon four-momentum. We study the VCS amplitude in the framework of chiral perturbation theory at ${\cal O}(p^4)$. At the one-loop level the generalized dipole polarizabilities are degenerate $\alpha_L(q^2)=\alpha_T(q^2)=-\beta(q^2)$. |
0809.0582 | Josip Trampetic Dr. | Raul Horvat, Peter Minkowski and Josip Trampetic | Dark consequences from light neutrino condensations | 5 pages; version to appear in PLB | Phys.Lett.B671:51-54,2009 | 10.1016/j.physletb.2008.11.055 | null | hep-ph astro-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we discuss light neutrino dipole moments, computed in the
neutrino-mass extended standard model (SM), as a possible source for neutrino
condensates which may cause cosmological constant observed today.
| [
{
"created": "Wed, 3 Sep 2008 09:31:32 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Nov 2008 10:57:37 GMT",
"version": "v2"
}
] | 2009-01-16 | [
[
"Horvat",
"Raul",
""
],
[
"Minkowski",
"Peter",
""
],
[
"Trampetic",
"Josip",
""
]
] | In this paper we discuss light neutrino dipole moments, computed in the neutrino-mass extended standard model (SM), as a possible source for neutrino condensates which may cause cosmological constant observed today. |
hep-ph/0312264 | Dominik Stockinger | S. Heinemeyer, D. St\"ockinger, G. Weiglein | Two-Loop SUSY Corrections to the Anomalous Magnetic Moment of the Muon | 18 pages, 7 figures, version to be published in NPB | Nucl.Phys. B690 (2004) 62-80 | 10.1016/j.nuclphysb.2004.04.017 | CERN-TH/2003-309, DCPT/03/148, DESY-03-153, IPPP/03/74, LMU 28/03 | hep-ph | null | We calculate supersymmetric two-loop corrections to the anomalous magnetic
moment of the muon, consisting of diagrams with a closed scalar fermion or
fermion loop and gauge and/or Higgs boson exchange. We discuss the numerical
impact of each subclass of diagrams and determine the leading contributions. We
analyze in detail constraints from experimental information on the Higgs boson
mass, Delta(rho), and the branching ratios of B -> X_s gamma and B_s -> mu^+
mu^-. If these constraints are taken into account, the largest possible
contributions are reduced from more than 2 sigma (in terms of the current
experimental error) to ~0.3 sigma. The only exceptions arise in rather extreme
parameter scenarios with a strong non-universality between the soft breaking
parameters in the stop and sbottom sectors.
| [
{
"created": "Thu, 18 Dec 2003 19:11:26 GMT",
"version": "v1"
},
{
"created": "Tue, 25 May 2004 16:41:21 GMT",
"version": "v2"
}
] | 2010-04-05 | [
[
"Heinemeyer",
"S.",
""
],
[
"Stöckinger",
"D.",
""
],
[
"Weiglein",
"G.",
""
]
] | We calculate supersymmetric two-loop corrections to the anomalous magnetic moment of the muon, consisting of diagrams with a closed scalar fermion or fermion loop and gauge and/or Higgs boson exchange. We discuss the numerical impact of each subclass of diagrams and determine the leading contributions. We analyze in detail constraints from experimental information on the Higgs boson mass, Delta(rho), and the branching ratios of B -> X_s gamma and B_s -> mu^+ mu^-. If these constraints are taken into account, the largest possible contributions are reduced from more than 2 sigma (in terms of the current experimental error) to ~0.3 sigma. The only exceptions arise in rather extreme parameter scenarios with a strong non-universality between the soft breaking parameters in the stop and sbottom sectors. |
2402.07195 | Fu-Lai Wang | Bao-Jun Lai, Fu-Lai Wang, and Xiang Liu | Investigating the M1 radiative decay behaviors and the magnetic moments
of the predicted triple-charm molecular-type pentaquarks | 10 pages, 2 figure, and 4 tables | Phys. Rev. D 109, 054036 (2024) | 10.1103/PhysRevD.109.054036 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we systematically study the electromagnetic properties
including the M1 radiative decay widths and the magnetic moments of the
isoscalar $\Xi_{c c} D^{(*)}$, $\Xi_{cc}D_{1}$, and $\Xi_{cc}D_{2}^{*}$
triple-charm molecular-type pentaquark candidates, where we adopt the
constituent quark model and consider both the $S$-$D$ wave mixing effect and
the coupled channel effect. Our numerical results suggest that the M1 radiative
decay widths and the magnetic moments of the isoscalar $\Xi_{c c} D^{(*)}$,
$\Xi_{cc}D_{1}$, and $\Xi_{cc}D_{2}^{*}$ triple-charm molecular-type pentaquark
candidates can reflect their inner structures, and the study of the
electromagnetic properties is the important step to construct the family of the
triple-charm molecular-type pentaquarks. With the accumulation of the
experimental data during the high-luminosity phase of LHC, we expect that the
present work combined with the corresponding mass spectrum information can
encourage the experimental colleagues at LHCb to focus on the isoscalar $\Xi_{c
c} D^{(*)}$, $\Xi_{cc}D_{1}$, and $\Xi_{cc}D_{2}^{*}$ triple-charm
molecular-type pentaquark candidates.
| [
{
"created": "Sun, 11 Feb 2024 13:15:13 GMT",
"version": "v1"
},
{
"created": "Sun, 10 Mar 2024 06:50:47 GMT",
"version": "v2"
},
{
"created": "Wed, 27 Mar 2024 02:15:05 GMT",
"version": "v3"
}
] | 2024-03-28 | [
[
"Lai",
"Bao-Jun",
""
],
[
"Wang",
"Fu-Lai",
""
],
[
"Liu",
"Xiang",
""
]
] | In this work, we systematically study the electromagnetic properties including the M1 radiative decay widths and the magnetic moments of the isoscalar $\Xi_{c c} D^{(*)}$, $\Xi_{cc}D_{1}$, and $\Xi_{cc}D_{2}^{*}$ triple-charm molecular-type pentaquark candidates, where we adopt the constituent quark model and consider both the $S$-$D$ wave mixing effect and the coupled channel effect. Our numerical results suggest that the M1 radiative decay widths and the magnetic moments of the isoscalar $\Xi_{c c} D^{(*)}$, $\Xi_{cc}D_{1}$, and $\Xi_{cc}D_{2}^{*}$ triple-charm molecular-type pentaquark candidates can reflect their inner structures, and the study of the electromagnetic properties is the important step to construct the family of the triple-charm molecular-type pentaquarks. With the accumulation of the experimental data during the high-luminosity phase of LHC, we expect that the present work combined with the corresponding mass spectrum information can encourage the experimental colleagues at LHCb to focus on the isoscalar $\Xi_{c c} D^{(*)}$, $\Xi_{cc}D_{1}$, and $\Xi_{cc}D_{2}^{*}$ triple-charm molecular-type pentaquark candidates. |
hep-ph/9306213 | Nir Polonsky-3C13-949 | Nir Polonsky | Coupling Constant and Yukawa Coupling Unifications: Uncertainties and
Constraints | (talk presented at the SUSY-93 Workshop), 7 pages + 2 figures
(figures are available upon request), LaTex, UPR-0571T | null | null | null | hep-ph | null | The status of coupling constant unification (with and without a unification
of Yukawa couplings) is discussed. Uncertainties associated with the input
coupling constants, $m_{b}$ and $m_{t}$, threshold corrections at the low and
high scale, and possible nonrenormalizable operators are described and a
discrepancy between effective and physical scales is pointed out. Theoretical
uncertainties in the predictions of $\alpha_{s}(M_{Z})$, $m_{b}$, and the
unification scale, $M_{G}$, are discussed and estimated. Constraints on the
super-partner spectrum are found to be weak if uncertainties associated with
the high-scale are included. However, requiring $h_{b} = h_{\tau}$ at $M_{G}$
excludes $3 < \tan \beta < 40$ (for $m_{t} < 200$ GeV).
| [
{
"created": "Wed, 2 Jun 1993 16:06:16 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Polonsky",
"Nir",
""
]
] | The status of coupling constant unification (with and without a unification of Yukawa couplings) is discussed. Uncertainties associated with the input coupling constants, $m_{b}$ and $m_{t}$, threshold corrections at the low and high scale, and possible nonrenormalizable operators are described and a discrepancy between effective and physical scales is pointed out. Theoretical uncertainties in the predictions of $\alpha_{s}(M_{Z})$, $m_{b}$, and the unification scale, $M_{G}$, are discussed and estimated. Constraints on the super-partner spectrum are found to be weak if uncertainties associated with the high-scale are included. However, requiring $h_{b} = h_{\tau}$ at $M_{G}$ excludes $3 < \tan \beta < 40$ (for $m_{t} < 200$ GeV). |
1805.05059 | Jin-Huan Sheng | Jin-Huan Sheng, Ru-Min Wang, Ya-Dong Yang | Effect of scalar leptoquarks on the lepton flavor violation decays of B
meson | 16 pages;5 figures Appendix; publication in International Journal of
Theoretical Physics | null | 10.1007/s10773-018-3948-3 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Leptoquarks have been suggested to solve a variety of discrepancies between
the expected and observed phenomenon. In this paper, we investigate the effect
of scalar leptoquarks on the lepton flavor violating B meson rare decays which
involve the quark level transition $\bar{b} \to \bar{s} \ell^-_i \ell^+_j(i
\neq j)$. The leptoquark parameter space is constrained by using the recently
measured upper limits on the $\mathcal{B}(B_s^0 \to \ell^-_i \ell^+_j)$ and
$\mathcal{B}(B \to K^{(*)}\ell^-_i \ell^+_j)$. Using such constrained
leptoquark parameter space, some relevant physical quantities are also
predicted and we find that the constrained New Physics parameters in the
leptoquark model have very obvious effects on the relevant physical quantities
in this paper. With future measurements of observable in $B \to K^{(*)}\ell^-_i
\ell^+_j$ decays at the LHCb, more and more differentiated from the other NP
explanations could be tested.
| [
{
"created": "Mon, 14 May 2018 08:25:27 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Jan 2019 03:38:08 GMT",
"version": "v2"
}
] | 2019-01-10 | [
[
"Sheng",
"Jin-Huan",
""
],
[
"Wang",
"Ru-Min",
""
],
[
"Yang",
"Ya-Dong",
""
]
] | Leptoquarks have been suggested to solve a variety of discrepancies between the expected and observed phenomenon. In this paper, we investigate the effect of scalar leptoquarks on the lepton flavor violating B meson rare decays which involve the quark level transition $\bar{b} \to \bar{s} \ell^-_i \ell^+_j(i \neq j)$. The leptoquark parameter space is constrained by using the recently measured upper limits on the $\mathcal{B}(B_s^0 \to \ell^-_i \ell^+_j)$ and $\mathcal{B}(B \to K^{(*)}\ell^-_i \ell^+_j)$. Using such constrained leptoquark parameter space, some relevant physical quantities are also predicted and we find that the constrained New Physics parameters in the leptoquark model have very obvious effects on the relevant physical quantities in this paper. With future measurements of observable in $B \to K^{(*)}\ell^-_i \ell^+_j$ decays at the LHCb, more and more differentiated from the other NP explanations could be tested. |
2201.08253 | Menglin Du Dr. | Meng-Lin Du, Miguel Albaladejo, Feng-Kun Guo, and Juan Nieves | A combined analysis of the $Z_c(3900)$ and the $Z_{cs}(3985)$ exotic
states | 27 pages, 9 figures, and 4 tables, version published in physical
review D | Phys.Rev.D 105 (2022) 074018 | 10.1103/PhysRevD.105.074018 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have performed a combined analysis of the BESIII data for both the
$Z_c(3900)$ and $Z_{cs}(3985)$ structures, assuming that the latter is an SU(3)
flavor partner of the former one. We have improved on the previous analysis of
Albaladejo $et$ $al.$ [Phys. Lett. B 755, 337 (2016)] by computing the
amplitude for the $D_1\bar{D}D^*$ triangle diagram considering both $D$ and
$S$-wave $D_1D^*\pi$ couplings. We have also investigated effects from SU(3)
light-flavor violations, which are found to be moderate and of the order of
20%. The successful reproduction of the BESIII spectra, in both the
hidden-charm and hidden-charm strange sectors, strongly supports that the
$Z_{cs}(3985)$ and $Z_c(3900)$ are SU(3) flavor partners placed in the same
octet multiplet. The best results are obtained when an energy-dependent term in
the diagonal $D^{(*)}\bar D_{(s)}^{(*)}$ interaction is included, leading to
resonances (poles above the thresholds) to describe these exotic states. We
have also made predictions for the isovector $Z_{c}^*$ and isodoublet
$Z_{cs}^*$, $D^*\bar{D}^*$ and $D^*\bar{D}_{s}^*$ molecules, with
$J^{PC}=1^{+-}$ and $J^{P}=1^{+}$, respectively. These states would be
heavy-quark spin symmetry partners of the $Z_{c}$ and $Z_{cs}$. Besides the
determination of the masses and widths of the $Z_c(3900)$ and $Z_{cs}(3985)$,
we also predict those of the $Z_c^*$ and $Z_{cs}^*$ resonances.
| [
{
"created": "Thu, 20 Jan 2022 16:00:24 GMT",
"version": "v1"
},
{
"created": "Mon, 2 May 2022 13:56:12 GMT",
"version": "v2"
}
] | 2022-05-05 | [
[
"Du",
"Meng-Lin",
""
],
[
"Albaladejo",
"Miguel",
""
],
[
"Guo",
"Feng-Kun",
""
],
[
"Nieves",
"Juan",
""
]
] | We have performed a combined analysis of the BESIII data for both the $Z_c(3900)$ and $Z_{cs}(3985)$ structures, assuming that the latter is an SU(3) flavor partner of the former one. We have improved on the previous analysis of Albaladejo $et$ $al.$ [Phys. Lett. B 755, 337 (2016)] by computing the amplitude for the $D_1\bar{D}D^*$ triangle diagram considering both $D$ and $S$-wave $D_1D^*\pi$ couplings. We have also investigated effects from SU(3) light-flavor violations, which are found to be moderate and of the order of 20%. The successful reproduction of the BESIII spectra, in both the hidden-charm and hidden-charm strange sectors, strongly supports that the $Z_{cs}(3985)$ and $Z_c(3900)$ are SU(3) flavor partners placed in the same octet multiplet. The best results are obtained when an energy-dependent term in the diagonal $D^{(*)}\bar D_{(s)}^{(*)}$ interaction is included, leading to resonances (poles above the thresholds) to describe these exotic states. We have also made predictions for the isovector $Z_{c}^*$ and isodoublet $Z_{cs}^*$, $D^*\bar{D}^*$ and $D^*\bar{D}_{s}^*$ molecules, with $J^{PC}=1^{+-}$ and $J^{P}=1^{+}$, respectively. These states would be heavy-quark spin symmetry partners of the $Z_{c}$ and $Z_{cs}$. Besides the determination of the masses and widths of the $Z_c(3900)$ and $Z_{cs}(3985)$, we also predict those of the $Z_c^*$ and $Z_{cs}^*$ resonances. |
1712.09873 | Sebastian Baum | Sebastian Baum, Marcela Carena, Nausheen R. Shah, Carlos E. M. Wagner | Higgs Portals for Thermal Dark Matter - EFT Perspectives and the NMSSM - | 42 pages, 14 figures. v2: added references, published in JHEP | JHEP04(2018)069 | 10.1007/JHEP04(2018)069 | NORDITA-2017-130, FERMILAB-PUB-17-611-T, EFI-17-25, WSU-HEP-1715 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze a low energy effective model of Dark Matter in which the thermal
relic density is provided by a singlet Majorana fermion which interacts with
the Higgs fields via higher dimensional operators. Direct detection signatures
may be reduced if blind spot solutions exist, which naturally appear in models
with extended Higgs sectors. Explicit mass terms for the Majorana fermion can
be forbidden by a $Z_3$ symmetry, which in addition leads to a reduction of the
number of higher dimensional operators. Moreover, a weak scale mass for the
Majorana fermion is naturally obtained from the vacuum expectation value of a
scalar singlet field. The proper relic density may be obtained by the
$s$-channel interchange of Higgs and gauge bosons, with the longitudinal mode
of the $Z$ boson (the neutral Goldstone mode) playing a relevant role in the
annihilation process. This model shares many properties with the
Next-to-Minimal Supersymmetric extension of the Standard Model (NMSSM) with
light singlinos and heavy scalar and gauge superpartners. In order to test the
validity of the low energy effective field theory, we compare its predictions
with those of the ultraviolet complete NMSSM. Extending our framework to
include $Z_3$ neutral Majorana fermions, analogous to the bino in the NMSSM, we
find the appearance of a new bino-singlino well tempered Dark Matter region.
| [
{
"created": "Thu, 28 Dec 2017 14:32:15 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Apr 2018 08:50:04 GMT",
"version": "v2"
}
] | 2018-04-18 | [
[
"Baum",
"Sebastian",
""
],
[
"Carena",
"Marcela",
""
],
[
"Shah",
"Nausheen R.",
""
],
[
"Wagner",
"Carlos E. M.",
""
]
] | We analyze a low energy effective model of Dark Matter in which the thermal relic density is provided by a singlet Majorana fermion which interacts with the Higgs fields via higher dimensional operators. Direct detection signatures may be reduced if blind spot solutions exist, which naturally appear in models with extended Higgs sectors. Explicit mass terms for the Majorana fermion can be forbidden by a $Z_3$ symmetry, which in addition leads to a reduction of the number of higher dimensional operators. Moreover, a weak scale mass for the Majorana fermion is naturally obtained from the vacuum expectation value of a scalar singlet field. The proper relic density may be obtained by the $s$-channel interchange of Higgs and gauge bosons, with the longitudinal mode of the $Z$ boson (the neutral Goldstone mode) playing a relevant role in the annihilation process. This model shares many properties with the Next-to-Minimal Supersymmetric extension of the Standard Model (NMSSM) with light singlinos and heavy scalar and gauge superpartners. In order to test the validity of the low energy effective field theory, we compare its predictions with those of the ultraviolet complete NMSSM. Extending our framework to include $Z_3$ neutral Majorana fermions, analogous to the bino in the NMSSM, we find the appearance of a new bino-singlino well tempered Dark Matter region. |
hep-ph/0301055 | Junegone Chay | Junegone Chay and Chul Kim | Factorization of B decays into two light mesons in soft-collinear
effective theory | 5 pages, 3 figures. Major revision. We concentrate on the
factorization properties in nonleptonic B decays | Phys.Rev. D68 (2003) 071502 | 10.1103/PhysRevD.68.071502 | KUPT-03-01 | hep-ph | null | We show that the amplitudes for B decays into two light mesons at leading
order in soft-collinear effective theory are factorized to all orders in
alpha_s. We construct gauge-invariant four-quark operators by employing the
effective theories SCET_I for sqrt{m_b \Lambda} <\mu<m_b, and SCET_II for \mu
<sqrt{m_b \Lambda} with Lambda ~0.5 GeV. These operators do not allow gluon
exchanges between different sectors of the current and the matrix elements are
reduced to the products of current matrix elements. The spectator interactions
are also factorized at leading order in SCET and to all orders in alpha_s.
| [
{
"created": "Thu, 9 Jan 2003 09:31:47 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Jul 2003 05:39:38 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Chay",
"Junegone",
""
],
[
"Kim",
"Chul",
""
]
] | We show that the amplitudes for B decays into two light mesons at leading order in soft-collinear effective theory are factorized to all orders in alpha_s. We construct gauge-invariant four-quark operators by employing the effective theories SCET_I for sqrt{m_b \Lambda} <\mu<m_b, and SCET_II for \mu <sqrt{m_b \Lambda} with Lambda ~0.5 GeV. These operators do not allow gluon exchanges between different sectors of the current and the matrix elements are reduced to the products of current matrix elements. The spectator interactions are also factorized at leading order in SCET and to all orders in alpha_s. |
hep-ph/0202211 | Tomohiro Matsuda | Tomohiro Matsuda | Affleck-Dine baryogenesis in the local domain | 18pages, latex2e, to appear in PRD | Phys.Rev. D65 (2002) 103502 | 10.1103/PhysRevD.65.103502 | null | hep-ph astro-ph hep-th | null | For Affleck-Dine baryogenesis to proceed, there must have been two types of
phase transitions. One is the destabilized-stabilized phase transition of the
flat direction, which is in general induced by the Hubble parameter. The other
is the phase transition related to the A-term, which induces the misalignment
of the relative phase of the flat direction. In the conventional Affleck-Dine
baryogenesis they are supposed to start almost simultaneously. Of course these
phase transitions can take place separately, but the latter must not be later
than the former because the phase transition of the A-term can not produce any
baryon number when there is no condensate of the relative charge.
In this paper we try to construct models where the original idea of
Affleck-Dine baryogenesis is realized in a different way. We show examples in
which the local domain of the false vacuum with the required condensate is
formed after inflation and collapses in a safe way so that the domain wall
problem is avoided. We also show examples where the phase transition of the
A-term starts before the decay of the condensate. As in the conventional
Affleck-Dine mechanism, the phase transition of the A-term produces baryon
number in the local domain of the condensate. We construct scenarios where our
mechanism produces sufficient baryon asymmetry of the Universe.
| [
{
"created": "Fri, 22 Feb 2002 13:20:45 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Mar 2002 07:33:33 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Matsuda",
"Tomohiro",
""
]
] | For Affleck-Dine baryogenesis to proceed, there must have been two types of phase transitions. One is the destabilized-stabilized phase transition of the flat direction, which is in general induced by the Hubble parameter. The other is the phase transition related to the A-term, which induces the misalignment of the relative phase of the flat direction. In the conventional Affleck-Dine baryogenesis they are supposed to start almost simultaneously. Of course these phase transitions can take place separately, but the latter must not be later than the former because the phase transition of the A-term can not produce any baryon number when there is no condensate of the relative charge. In this paper we try to construct models where the original idea of Affleck-Dine baryogenesis is realized in a different way. We show examples in which the local domain of the false vacuum with the required condensate is formed after inflation and collapses in a safe way so that the domain wall problem is avoided. We also show examples where the phase transition of the A-term starts before the decay of the condensate. As in the conventional Affleck-Dine mechanism, the phase transition of the A-term produces baryon number in the local domain of the condensate. We construct scenarios where our mechanism produces sufficient baryon asymmetry of the Universe. |
1811.10586 | Alejandro Correa L\'opez | Alejandro Correa L\'opez | Electroweak phase transition in the scotogenic model | 5 pages, LaTeX, 6 PDF figures. Invited talk at PIC2018: XXXVIII
International Symposium on Physics in Collision, Bogot\'a, Colombia, 2018 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we study the behavior of the effective scalar potential at zero
and finite temperature of the scotogenic model. In particular, we analyze the
impact of the Yukawa couplings associated to the right--handed neutrinos on the
electroweak phase transition.
| [
{
"created": "Mon, 26 Nov 2018 18:42:30 GMT",
"version": "v1"
}
] | 2018-11-27 | [
[
"López",
"Alejandro Correa",
""
]
] | In this work we study the behavior of the effective scalar potential at zero and finite temperature of the scotogenic model. In particular, we analyze the impact of the Yukawa couplings associated to the right--handed neutrinos on the electroweak phase transition. |
2303.17433 | Patrick Foldenauer | Patrick Foldenauer | On Consistent Kinetic Mixing and the Higgs Low-Energy Theorems | 8 pages, 3 figures, Contribution to the proceedings of 8th Symposium
on Prospects in the Physics of Discrete Symmetries - DISCRETE 2022, 7-11
November 2022, Baden-Baden, Germany | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | A popular class of extensions of the Standard Model (SM) are models of a new
Abelian gauge boson $X$, called $dark$ or $hidden\ photon$, that kinetically
mixes with the SM photon. We revisit the matching procedure of kinetic mixing
terms in the electroweak symmetric phase to the ones in the broken phase. Our
central finding is that in order to obtain the correct matching prescription
one has to take into account mixing of the hidden photon with the neutral
component of the weak $SU(2)_L$ bosons. This mixing is generated by a
dimension-six operator and, in theories where $SU(2)_L$ multiplets are charged
under the novel Abelian gauge group, is necessarily induced at the one-loop
level. We illustrate this matching procedure for the loop-generated kinetic
mixing in $U(1)_{L_\mu-L_\tau}$. Furthermore, we show how to obtain general
expressions for the Higgs decay amplitudes to two neutral vector bosons from
the vacuum polarisation amplitudes via the low-energy theorems. As an
application, we derive general expression for the branching ratios of the
decays $h\to\gamma X$ and $h\to XX$ in $U(1)_{B-L}$.
| [
{
"created": "Thu, 30 Mar 2023 14:58:26 GMT",
"version": "v1"
}
] | 2023-03-31 | [
[
"Foldenauer",
"Patrick",
""
]
] | A popular class of extensions of the Standard Model (SM) are models of a new Abelian gauge boson $X$, called $dark$ or $hidden\ photon$, that kinetically mixes with the SM photon. We revisit the matching procedure of kinetic mixing terms in the electroweak symmetric phase to the ones in the broken phase. Our central finding is that in order to obtain the correct matching prescription one has to take into account mixing of the hidden photon with the neutral component of the weak $SU(2)_L$ bosons. This mixing is generated by a dimension-six operator and, in theories where $SU(2)_L$ multiplets are charged under the novel Abelian gauge group, is necessarily induced at the one-loop level. We illustrate this matching procedure for the loop-generated kinetic mixing in $U(1)_{L_\mu-L_\tau}$. Furthermore, we show how to obtain general expressions for the Higgs decay amplitudes to two neutral vector bosons from the vacuum polarisation amplitudes via the low-energy theorems. As an application, we derive general expression for the branching ratios of the decays $h\to\gamma X$ and $h\to XX$ in $U(1)_{B-L}$. |
1310.2376 | Grigory Rubtsov | A.D. Dolgov, S.L. Dubovsky, G.I. Rubtsov and I.I. Tkachev | Constraints on millicharged particles from Planck | 4 pages, 3 figures | Phys. Rev. D 88, 117701 (2013) | 10.1103/PhysRevD.88.117701 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit cosmic microwave background (CMB) constraints on the abundance of
millicharged particles based on the Planck data. The stringent limit
Omega_{mcp}h^2 < 0.001 (95% CL) may be set using the CMB data alone if
millicharged particles participate in the acoustic oscillations of
baryon-photon plasma at the recombination epoch. The latter condition is valid
for a wide region of charges and masses of the particles. Adding the
millicharged component to LCDM shifts prefered scalar spectral index of
primordial perturbations to somewhat larger values as compared to minimal
model, even approaching Harrison-Zeldovich spectrum under some assumptions.
| [
{
"created": "Wed, 9 Oct 2013 07:20:26 GMT",
"version": "v1"
}
] | 2013-12-16 | [
[
"Dolgov",
"A. D.",
""
],
[
"Dubovsky",
"S. L.",
""
],
[
"Rubtsov",
"G. I.",
""
],
[
"Tkachev",
"I. I.",
""
]
] | We revisit cosmic microwave background (CMB) constraints on the abundance of millicharged particles based on the Planck data. The stringent limit Omega_{mcp}h^2 < 0.001 (95% CL) may be set using the CMB data alone if millicharged particles participate in the acoustic oscillations of baryon-photon plasma at the recombination epoch. The latter condition is valid for a wide region of charges and masses of the particles. Adding the millicharged component to LCDM shifts prefered scalar spectral index of primordial perturbations to somewhat larger values as compared to minimal model, even approaching Harrison-Zeldovich spectrum under some assumptions. |
hep-ph/0602079 | Eduard De La Cruz Burelo | Homer A. Neal and Eduard De La Cruz Burelo | Hyperon Polarization in a Quark-Quark Scattering Model | 17 pages, 9 figures | null | 10.1063/1.2750818 | null | hep-ph | null | A continuing mystery in particle physics is the large polarization observed
in inclusive hyperon production in high energy p-p collisions. In this paper
the authors advance the concept that the polarization effects can be accounted
for in a simple model based on quarks becoming polarized in the direct q-q
scattering process and where, at a fundamental level, the s quark is treated no
differently than the u and d, except that it is required to have been created
as part of a s-sbar pair prior to the collision. The q-q polarization
parameters are extracted from p-p elastic scattering using a previous model and
these are used to predict the Lambda polarization from the p-p data. Remarkably
good agreement is obtained, raising the possibility that the large hyperon
polarizations are no more of a mystery than the p-p polarization itself and
that, at least at small pt, the two may be simply related. This concept is
extended in an attempt to explain the polarizations observed in other inclusive
hyperon processes with the finding that hyperon and elastic polarizations,
which previously seemed almost unrelated, may have a simple and common origin.
| [
{
"created": "Thu, 9 Feb 2006 11:54:54 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Neal",
"Homer A.",
""
],
[
"Burelo",
"Eduard De La Cruz",
""
]
] | A continuing mystery in particle physics is the large polarization observed in inclusive hyperon production in high energy p-p collisions. In this paper the authors advance the concept that the polarization effects can be accounted for in a simple model based on quarks becoming polarized in the direct q-q scattering process and where, at a fundamental level, the s quark is treated no differently than the u and d, except that it is required to have been created as part of a s-sbar pair prior to the collision. The q-q polarization parameters are extracted from p-p elastic scattering using a previous model and these are used to predict the Lambda polarization from the p-p data. Remarkably good agreement is obtained, raising the possibility that the large hyperon polarizations are no more of a mystery than the p-p polarization itself and that, at least at small pt, the two may be simply related. This concept is extended in an attempt to explain the polarizations observed in other inclusive hyperon processes with the finding that hyperon and elastic polarizations, which previously seemed almost unrelated, may have a simple and common origin. |
0903.0899 | Boris Kayser | Boris Kayser | Are Neutrinos Their Own Antiparticles? | 8 pages, pdf | J.Phys.Conf.Ser.173:012013,2009 | 10.1088/1742-6596/173/1/012013 | FERMILAB-CONF-09-058-T | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explain the relationship between Majorana neutrinos, which are their own
antiparticles, and Majorana neutrino masses. We point out that Majorana masses
would make the neutrinos very distinctive particles, and explain why many
theorists strongly suspect that neutrinos do have Majorana masses. The
promising approach to confirming this suspicion is to seek neutrinoless double
beta decay. We introduce a toy model that illustrates why this decay requires
nonzero neutrino masses, even when there are both right-handed and left-handed
weak currents.
| [
{
"created": "Thu, 5 Mar 2009 03:04:47 GMT",
"version": "v1"
}
] | 2009-07-24 | [
[
"Kayser",
"Boris",
""
]
] | We explain the relationship between Majorana neutrinos, which are their own antiparticles, and Majorana neutrino masses. We point out that Majorana masses would make the neutrinos very distinctive particles, and explain why many theorists strongly suspect that neutrinos do have Majorana masses. The promising approach to confirming this suspicion is to seek neutrinoless double beta decay. We introduce a toy model that illustrates why this decay requires nonzero neutrino masses, even when there are both right-handed and left-handed weak currents. |
hep-ph/0209251 | Neil Russell | Neil Russell | Investigating Lorentz and CPT Symmetry with Antihydrogen | 10 pages, latex, invited talk at XIVth Rencontres de Blois on
Matter-Antimatter Asymmetry, Chateau de Blois, France, 16-22 June 2002 | null | null | null | hep-ph | null | This talk discusses theoretical aspects of tests of CPT and Lorentz Symmetry
that will in principle be possible with trapped antihydrogen. The framework is
the standard-model extension, which admits minuscule violations of CPT and
Lorentz symmetry in a general manner without giving up other features of the
standard model of particle physics. Spectroscopic transitions in hydrogen and
antihydrogen that exhibit leading-order effects are identified. Such
comparisons of spectral frequencies in antimatter with the corresponding
frequencies in regular matter will bound parameter combinations that are not
accessible with regular-matter atoms alone.
| [
{
"created": "Mon, 23 Sep 2002 02:47:26 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Russell",
"Neil",
""
]
] | This talk discusses theoretical aspects of tests of CPT and Lorentz Symmetry that will in principle be possible with trapped antihydrogen. The framework is the standard-model extension, which admits minuscule violations of CPT and Lorentz symmetry in a general manner without giving up other features of the standard model of particle physics. Spectroscopic transitions in hydrogen and antihydrogen that exhibit leading-order effects are identified. Such comparisons of spectral frequencies in antimatter with the corresponding frequencies in regular matter will bound parameter combinations that are not accessible with regular-matter atoms alone. |
2008.03409 | Yohan Mauricio Oviedo Torres | D. Cogollo, F. F. Freitas, C. A. de S. Pires, Yohan M. Oviedo-Torres,
P. Vasconcelos | Deep learnig analysis of the inverse seesaw in a 3-3-1 model at the LHC | null | null | 10.1016/j.physletb.2020.135931 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inverse seesaw is a genuine TeV scale seesaw mechanism. In it active
neutrinos with masses at eV scale requires lepton number be explicitly violated
at keV scale and the existence of new physics, in the form of heavy neutrinos,
at TeV scale. Therefore it is a phenomenologically viable seesaw mechanism
since its signature may be probed at the LHC. Moreover it is successfully
embedded into gauge extensions of the standard model as the 3-3-1 model with
the right-handed neutrinos. In this work we revisit the implementation of this
mechanism into the 3-3-1 model and employ deep learning analysis to probe such
setting at the LHC and, as main result, we have that if its signature is not
detected in the next LHC running with energy of 14 TeVs, then, the vector boson
$Z^{\prime}$ of the 3-3-1 model must be heavier than 4 TeVs.
| [
{
"created": "Sat, 8 Aug 2020 01:06:19 GMT",
"version": "v1"
}
] | 2020-11-11 | [
[
"Cogollo",
"D.",
""
],
[
"Freitas",
"F. F.",
""
],
[
"Pires",
"C. A. de S.",
""
],
[
"Oviedo-Torres",
"Yohan M.",
""
],
[
"Vasconcelos",
"P.",
""
]
] | Inverse seesaw is a genuine TeV scale seesaw mechanism. In it active neutrinos with masses at eV scale requires lepton number be explicitly violated at keV scale and the existence of new physics, in the form of heavy neutrinos, at TeV scale. Therefore it is a phenomenologically viable seesaw mechanism since its signature may be probed at the LHC. Moreover it is successfully embedded into gauge extensions of the standard model as the 3-3-1 model with the right-handed neutrinos. In this work we revisit the implementation of this mechanism into the 3-3-1 model and employ deep learning analysis to probe such setting at the LHC and, as main result, we have that if its signature is not detected in the next LHC running with energy of 14 TeVs, then, the vector boson $Z^{\prime}$ of the 3-3-1 model must be heavier than 4 TeVs. |
1902.02791 | Zoltan Peli | Zolt\'an P\'eli and Zolt\'an Tr\'ocs\'anyi | Stability of the vacuum as constraint on $U$(1) extensions of the
standard model | 13 pages, 6 figures | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the standard model the running quartic coupling becomes negative during
its renormalization group flow, which destabilizes the vacuum. We consider U(1)
extensions of the standard model, with an extra complex scalar field and a
Majorana-type neutrino Yukawa coupling. These additional couplings affect the
renormalization group flow of the quartic couplings. We compute the
beta-functions of the extended model at one-loop order in perturbation theory
and study how the parameter space of the new scalar couplings can be
constrained by the requirement of stable vacuum and perturbativity up to the
Planck scale.
| [
{
"created": "Thu, 7 Feb 2019 19:00:02 GMT",
"version": "v1"
}
] | 2019-02-11 | [
[
"Péli",
"Zoltán",
""
],
[
"Trócsányi",
"Zoltán",
""
]
] | In the standard model the running quartic coupling becomes negative during its renormalization group flow, which destabilizes the vacuum. We consider U(1) extensions of the standard model, with an extra complex scalar field and a Majorana-type neutrino Yukawa coupling. These additional couplings affect the renormalization group flow of the quartic couplings. We compute the beta-functions of the extended model at one-loop order in perturbation theory and study how the parameter space of the new scalar couplings can be constrained by the requirement of stable vacuum and perturbativity up to the Planck scale. |
hep-ph/0011193 | Kieran Holland | K. Holland and U.-J. Wiese | The Center symmetry and its spontaneous breakdown at high temperatures | LaTex, 35 pages, 6 figures, uses sprocl.sty. To be published in the
Festschrift in honor of B.L. Ioffe, "At the Frontier of Particle Physics/
Handbook of QCD", edited by M. Shifman | null | 10.1142/9789812810458_0040 | BUTP-2000/34, MIT-CTP 3045 | hep-ph hep-lat hep-th | null | We examine the role of the center Z(N) of the gauge group SU(N) in gauge
theories. In this pedagogical article, we discuss, among other topics, the
center symmetry and confinement and deconfinement in gauge theories and
associated finite-temperature phase transitions. We also look at universal
properties of domain walls separating distinct confined and deconfined bulk
phases, including a description of how QCD color-flux strings can end on
color-neutral domain walls, and unusual finite-volume dependence in which
quarks in deconfined bulk phase seem to be "confined".
| [
{
"created": "Wed, 15 Nov 2000 16:33:40 GMT",
"version": "v1"
}
] | 2016-11-23 | [
[
"Holland",
"K.",
""
],
[
"Wiese",
"U. -J.",
""
]
] | We examine the role of the center Z(N) of the gauge group SU(N) in gauge theories. In this pedagogical article, we discuss, among other topics, the center symmetry and confinement and deconfinement in gauge theories and associated finite-temperature phase transitions. We also look at universal properties of domain walls separating distinct confined and deconfined bulk phases, including a description of how QCD color-flux strings can end on color-neutral domain walls, and unusual finite-volume dependence in which quarks in deconfined bulk phase seem to be "confined". |
1611.08609 | Emanuele Roberto Nocera | Micha{\l} Czakon, Nathan P. Hartland, Alexander Mitov, Emanuele R.
Nocera and Juan Rojo | Pinning down the large-x gluon with NNLO top-quark pair differential
distributions | 42 pages, 21 figures, 11 tables, this version match the version
accepted for publication in JHEP | null | 10.1007/JHEP04(2017)044 | OUTP-16-15P, Nikhef/2016-046, Cavendish-HEP-16/17, Aachen-TTK-16-49 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Top-quark pair production at the LHC is directly sensitive to the gluon PDF
at large x. While total cross-section data is already included in several PDF
determinations, differential distributions are not, because the corresponding
NNLO calculations have become available only recently. In this work we study
the impact on the large-x gluon of top-quark pair differential distributions
measured by ATLAS and CMS at $\sqrt{s}=8$ TeV. Our analysis, performed in the
NNPDF3.0 framework at NNLO accuracy, allows us to identify the optimal
combination of LHC top-quark pair measurements that maximize the constraints on
the gluon, as well as to assess the compatibility between ATLAS and CMS data.
We find that differential distributions from top-quark pair production provide
significant constraints on the large-x gluon, comparable to those obtained from
inclusive jet production data, and thus should become an important ingredient
for the next generation of global PDF fits.
| [
{
"created": "Fri, 25 Nov 2016 21:00:06 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Mar 2017 12:23:35 GMT",
"version": "v2"
}
] | 2017-04-26 | [
[
"Czakon",
"Michał",
""
],
[
"Hartland",
"Nathan P.",
""
],
[
"Mitov",
"Alexander",
""
],
[
"Nocera",
"Emanuele R.",
""
],
[
"Rojo",
"Juan",
""
]
] | Top-quark pair production at the LHC is directly sensitive to the gluon PDF at large x. While total cross-section data is already included in several PDF determinations, differential distributions are not, because the corresponding NNLO calculations have become available only recently. In this work we study the impact on the large-x gluon of top-quark pair differential distributions measured by ATLAS and CMS at $\sqrt{s}=8$ TeV. Our analysis, performed in the NNPDF3.0 framework at NNLO accuracy, allows us to identify the optimal combination of LHC top-quark pair measurements that maximize the constraints on the gluon, as well as to assess the compatibility between ATLAS and CMS data. We find that differential distributions from top-quark pair production provide significant constraints on the large-x gluon, comparable to those obtained from inclusive jet production data, and thus should become an important ingredient for the next generation of global PDF fits. |
1204.6471 | Ilnur Gabdrakhmanov | I. R. Gabdrakhmanov, O. V. Teryaev | Analyticity and sum rules for photon GPDs | Version to appear in Physics Letters B | null | 10.1016/j.physletb.2012.08.041 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The photon is explored as an object to test the applications of QCD to the
perturbatively calculable collinear parton distributions. We investigate
analytic properties of DVCS amplitudes and related sum rules of generalized
parton distributions of the photon using as an input their earlier calculations
in the leading order. The relation of these GPDs to the quintessential
functions in the framework of the dual parametrization approach is also found.
| [
{
"created": "Sun, 29 Apr 2012 12:15:43 GMT",
"version": "v1"
},
{
"created": "Wed, 2 May 2012 21:05:09 GMT",
"version": "v2"
},
{
"created": "Mon, 7 May 2012 21:42:18 GMT",
"version": "v3"
},
{
"created": "Thu, 14 Jun 2012 19:40:56 GMT",
"version": "v4"
},
{
"cre... | 2012-09-25 | [
[
"Gabdrakhmanov",
"I. R.",
""
],
[
"Teryaev",
"O. V.",
""
]
] | The photon is explored as an object to test the applications of QCD to the perturbatively calculable collinear parton distributions. We investigate analytic properties of DVCS amplitudes and related sum rules of generalized parton distributions of the photon using as an input their earlier calculations in the leading order. The relation of these GPDs to the quintessential functions in the framework of the dual parametrization approach is also found. |
hep-ph/0501145 | Xuelei Wang | Xuelei Wang, Qiaoli Zhang, Qingpeng Qiao | Studying top quark decay into the polarized W-boson in the TC2 model | 8 pages, 4 figures | Phys.Rev.D71:014035,2005 | 10.1103/PhysRevD.71.014035 | null | hep-ph | null | We study the decay mode of top quark decaying into Wb in the TC2 model where
the top quark is distinguished from other fermions by participating in a strong
interaction. We find that the TC2 correction to the decay width $\Gamma (t \to
b W) $ is generally several percent and maximum value can reach 8% for the
currently allowed parameters. The magnitude of such correction is comparable
with QCD correction and larger than that of minimal supersymmetric model. Such
correction might be observable in the future colliders. We also study the TC2
correction to the branching ratio of top quark decay into the polarized W
bosons and find the correction is below $ 1 % $. After considering the TC2
correction, we find that our theoretical predictions about the decay branching
ratio are also consistent with the experimental data.
| [
{
"created": "Sun, 16 Jan 2005 13:24:06 GMT",
"version": "v1"
}
] | 2011-03-23 | [
[
"Wang",
"Xuelei",
""
],
[
"Zhang",
"Qiaoli",
""
],
[
"Qiao",
"Qingpeng",
""
]
] | We study the decay mode of top quark decaying into Wb in the TC2 model where the top quark is distinguished from other fermions by participating in a strong interaction. We find that the TC2 correction to the decay width $\Gamma (t \to b W) $ is generally several percent and maximum value can reach 8% for the currently allowed parameters. The magnitude of such correction is comparable with QCD correction and larger than that of minimal supersymmetric model. Such correction might be observable in the future colliders. We also study the TC2 correction to the branching ratio of top quark decay into the polarized W bosons and find the correction is below $ 1 % $. After considering the TC2 correction, we find that our theoretical predictions about the decay branching ratio are also consistent with the experimental data. |
hep-ph/9907353 | Michael R. Pennington | M.R. Pennington | Exclusive channels in $\gamma\gamma$ reactions: light at the end of the
tunnel? | 9 pages,8 figures. Invited introductory talk at Photon'99, Freiburg
im Br., Germany, May 1999 | Nucl.Phys.Proc.Suppl. 82 (2000) 291-299 | 10.1016/S0920-5632(00)00167-5 | DTP-99/74 | hep-ph | null | The physics that can be learnt by studying exclusive channels in two photon
interactions is recalled. This serves as an introduction to the Exclusive
Reaction session of Photon'99.
| [
{
"created": "Wed, 14 Jul 1999 16:51:54 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Pennington",
"M. R.",
""
]
] | The physics that can be learnt by studying exclusive channels in two photon interactions is recalled. This serves as an introduction to the Exclusive Reaction session of Photon'99. |
hep-ph/0205276 | Jan Nemcik | J. Nemchik | Incoherent Production of Charmonia off Nuclei As a Good Tool for Study
of Color Transparency | 26 pages including 7 figures | Phys.Rev. C66 (2002) 045204 | 10.1103/PhysRevC.66.045204 | null | hep-ph | null | Within a light-cone QCD formalism which incorporates color transparency (CT),
coherence length (CL) effects and gluon shadowing (GS) we study
electroproduction of charmonia off nuclei. In contrast to production of light
vector mesons (rho^0, phi^0) when at small and medium energies CT and the onset
of CL effects are not easily separated, in production of charmonia CT effects
dominate. We found rather large CT effects in the range of Q^2 < 20 GeV^2. They
are stronger at low than at high energies and can be easily identified by the
planned future experiments. Our parameter-free calculations explain well the
NMC data for variation with photon energy of the Sn/C ratio of nuclear
transparencies. We provide predictions for incoherent and coherent production
of charmonia for future measurements.
| [
{
"created": "Fri, 24 May 2002 10:58:33 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Nemchik",
"J.",
""
]
] | Within a light-cone QCD formalism which incorporates color transparency (CT), coherence length (CL) effects and gluon shadowing (GS) we study electroproduction of charmonia off nuclei. In contrast to production of light vector mesons (rho^0, phi^0) when at small and medium energies CT and the onset of CL effects are not easily separated, in production of charmonia CT effects dominate. We found rather large CT effects in the range of Q^2 < 20 GeV^2. They are stronger at low than at high energies and can be easily identified by the planned future experiments. Our parameter-free calculations explain well the NMC data for variation with photon energy of the Sn/C ratio of nuclear transparencies. We provide predictions for incoherent and coherent production of charmonia for future measurements. |
hep-ph/0203089 | Vittorio Lubicz | E. Franco, V. Lubicz, F. Mescia and C. Tarantino | Lifetime Ratios of Beauty Hadrons at the Next-to-Leading Order in QCD | 24 pages, 4 figures | Nucl.Phys. B633 (2002) 212-236 | 10.1016/S0550-3213(02)00262-6 | RM3-TH/02-3, ROME1-1333/02, SHEP 02/04 | hep-ph hep-lat | null | We compute the next-to-leading order QCD corrections to spectator effects in
the lifetime ratios of beauty hadrons. With respect to previous calculations,
we take into account the non vanishing value of the charm quark mass. We obtain
the predictions tau(B+)/tau(Bd) = 1.06 +- 0.02, tau(Bs)/tau(Bd)= 1.00 +- 0.01
and tau(Lambdab)/tau(Bd) = 0.90 +- 0.05, in good agreement with the
experimental results. In the case of tau(Bs)/tau(Bd) and tau(Lambdab)/tau(Bd),
however, some contributions, which either vanish in the vacuum insertion
approximation or represent a pure NLO corrections, have not been determined
yet.
| [
{
"created": "Fri, 8 Mar 2002 17:15:58 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Franco",
"E.",
""
],
[
"Lubicz",
"V.",
""
],
[
"Mescia",
"F.",
""
],
[
"Tarantino",
"C.",
""
]
] | We compute the next-to-leading order QCD corrections to spectator effects in the lifetime ratios of beauty hadrons. With respect to previous calculations, we take into account the non vanishing value of the charm quark mass. We obtain the predictions tau(B+)/tau(Bd) = 1.06 +- 0.02, tau(Bs)/tau(Bd)= 1.00 +- 0.01 and tau(Lambdab)/tau(Bd) = 0.90 +- 0.05, in good agreement with the experimental results. In the case of tau(Bs)/tau(Bd) and tau(Lambdab)/tau(Bd), however, some contributions, which either vanish in the vacuum insertion approximation or represent a pure NLO corrections, have not been determined yet. |
2308.14270 | Junle Pei | Junle Pei, Xinchou Lou, Yaquan Fang, Jinfei Wu, and Manqi Ruan | Radiative Leptonic Decay of Heavy Quarkonia | 16 pages, 6 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This study examines the properties of heavy quarkonia $X$ by treating them as
bound states of $Q$ and $\bar{Q}$ at the LO level within the NRQCD framework,
where $Q$ represents either a charm or a bottom quark. The branching ratios for
the radiative leptonic decays $X\rightarrow \gamma l^{+} l^{-}$ are revisited
and the angular and energy/momentum distributions of the final state particles
are analyzed in the rest frame of $X$. Furthermore, we apply Lorentz
transformations from the rest frame of $X$ to the center-of-mass frame of $l^+
l^-$ to establish the connection between the widths ${\Gamma_{X \rightarrow
\gamma l^{+} l^{-}}}$ and ${\Gamma_{X \rightarrow l^{+} l^{-}}}$. When
comparing the connection with those documented in the literature (divided by
$2\pi$) for various $X$ states, such as $J/\Psi$, $\Psi(2S)$, $\Upsilon(1S)$,
and $\Upsilon(2S)$, relative differences typically around or below 10\% can be
found, which is comparable to the NLO corrections of $O(\alpha)$ and $O(v^4)$.
However, we observe a significant disparity in the ratio between
${\Gamma_{\Psi(2S) \to \gamma \tau^+ \tau^-}}$ and ${\Gamma_{\Psi(2S) \to
\tau^+ \tau^-}}$, with our prediction being four times larger than those in the
literature. The outcomes derived from this study held practical implications in
describing the QED radiative processes and contribute to the investigation of
QCD processes associated with the decays of heavy quarkonia and the searches
for new physics.
| [
{
"created": "Mon, 28 Aug 2023 02:57:49 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Jul 2024 04:44:07 GMT",
"version": "v2"
}
] | 2024-07-19 | [
[
"Pei",
"Junle",
""
],
[
"Lou",
"Xinchou",
""
],
[
"Fang",
"Yaquan",
""
],
[
"Wu",
"Jinfei",
""
],
[
"Ruan",
"Manqi",
""
]
] | This study examines the properties of heavy quarkonia $X$ by treating them as bound states of $Q$ and $\bar{Q}$ at the LO level within the NRQCD framework, where $Q$ represents either a charm or a bottom quark. The branching ratios for the radiative leptonic decays $X\rightarrow \gamma l^{+} l^{-}$ are revisited and the angular and energy/momentum distributions of the final state particles are analyzed in the rest frame of $X$. Furthermore, we apply Lorentz transformations from the rest frame of $X$ to the center-of-mass frame of $l^+ l^-$ to establish the connection between the widths ${\Gamma_{X \rightarrow \gamma l^{+} l^{-}}}$ and ${\Gamma_{X \rightarrow l^{+} l^{-}}}$. When comparing the connection with those documented in the literature (divided by $2\pi$) for various $X$ states, such as $J/\Psi$, $\Psi(2S)$, $\Upsilon(1S)$, and $\Upsilon(2S)$, relative differences typically around or below 10\% can be found, which is comparable to the NLO corrections of $O(\alpha)$ and $O(v^4)$. However, we observe a significant disparity in the ratio between ${\Gamma_{\Psi(2S) \to \gamma \tau^+ \tau^-}}$ and ${\Gamma_{\Psi(2S) \to \tau^+ \tau^-}}$, with our prediction being four times larger than those in the literature. The outcomes derived from this study held practical implications in describing the QED radiative processes and contribute to the investigation of QCD processes associated with the decays of heavy quarkonia and the searches for new physics. |
0808.2425 | Philipp Kostka | Stefan Antusch, Mar Bastero-Gil, Koushik Dutta, Steve F. King and
Philipp M. Kostka | Solving the $\eta$-Problem in Hybrid Inflation with Heisenberg Symmetry
and Stabilized Modulus | 27 pages, 4 figures; appendix and reference added; version published
in JCAP | JCAP 0901:040,2009 | 10.1088/1475-7516/2009/01/040 | CAFPE-103/08, MPP-2008-108, UGFT-233/08 | hep-ph astro-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a class of models in which the $\eta$-problem of supersymmetric
hybrid inflation is resolved using a Heisenberg symmetry, where the associated
modulus field is stabilized and made heavy with the help of the large vacuum
energy during inflation without any fine-tuning. The proposed class of models
is well motivated both from string theory considerations, since it includes the
commonly encountered case of no-scale supergravity Kaehler potential, and from
the perspective of particle physics since a natural candidate for the inflaton
in this class of models is the right-handed sneutrino which is massless during
the inflationary epoch, and subsequently acquires a large mass at the end of
inflation. We study a specific example motivated by sneutrino hybrid inflation
with no-scale supergravity in some detail, and show that the spectral index may
lie within the latest WMAP range, while the tensor-to-scalar ratio is very
small.
| [
{
"created": "Mon, 18 Aug 2008 17:35:50 GMT",
"version": "v1"
},
{
"created": "Tue, 27 Jan 2009 16:03:49 GMT",
"version": "v2"
}
] | 2009-02-05 | [
[
"Antusch",
"Stefan",
""
],
[
"Bastero-Gil",
"Mar",
""
],
[
"Dutta",
"Koushik",
""
],
[
"King",
"Steve F.",
""
],
[
"Kostka",
"Philipp M.",
""
]
] | We propose a class of models in which the $\eta$-problem of supersymmetric hybrid inflation is resolved using a Heisenberg symmetry, where the associated modulus field is stabilized and made heavy with the help of the large vacuum energy during inflation without any fine-tuning. The proposed class of models is well motivated both from string theory considerations, since it includes the commonly encountered case of no-scale supergravity Kaehler potential, and from the perspective of particle physics since a natural candidate for the inflaton in this class of models is the right-handed sneutrino which is massless during the inflationary epoch, and subsequently acquires a large mass at the end of inflation. We study a specific example motivated by sneutrino hybrid inflation with no-scale supergravity in some detail, and show that the spectral index may lie within the latest WMAP range, while the tensor-to-scalar ratio is very small. |
1008.1323 | Oleg Selyugin | O.V. Selyugin | Gravitation form-factors and spin asymmetries in hadron elastic
scattering | 6 pages, 6 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of the model, where the scattering amplitude is determined
by the first and second moments of the GPDs, the qualitative description of all
existing experimental data at $\sqrt{s} \geq 52.8 $ GeV, including the Coulomb
range and large momentum transfers, is obtained with only 4 free parameters.
The spin-flip amplitude of the nucleon-nucleon elastic scattering is determined
taking into account the spin-dependence part of the second moment of the
generalized parton distributions (GPDs) with a new set of $t $-dependence.
The corresponding value of the % analyzing power $A_N$ for the $pp$ at high
energy (RHIC) elastic scattering is obtained.
| [
{
"created": "Sat, 7 Aug 2010 11:27:33 GMT",
"version": "v1"
}
] | 2010-08-10 | [
[
"Selyugin",
"O. V.",
""
]
] | In the framework of the model, where the scattering amplitude is determined by the first and second moments of the GPDs, the qualitative description of all existing experimental data at $\sqrt{s} \geq 52.8 $ GeV, including the Coulomb range and large momentum transfers, is obtained with only 4 free parameters. The spin-flip amplitude of the nucleon-nucleon elastic scattering is determined taking into account the spin-dependence part of the second moment of the generalized parton distributions (GPDs) with a new set of $t $-dependence. The corresponding value of the % analyzing power $A_N$ for the $pp$ at high energy (RHIC) elastic scattering is obtained. |
2111.04241 | Sh\=an Hu\'ang | Shan Huang (for the LUXE Collaboration) | LUXE: A new experiment to study non-perturbative QED in electron-laser
and photon-laser collisions | Conference proceedings for PANIC 2021 parallel talk on 5 Sep 2021, to
be published in the Proceedings of Science; minor wording changes and
adjustments | null | 10.22323/1.380.0429 | null | hep-ph hep-ex physics.ins-det physics.optics | http://creativecommons.org/licenses/by-nc-nd/4.0/ | LUXE (Laser Und XFEL Experiment) is a new experiment in planning at DESY
Hamburg using the electron beam of the European XFEL. LUXE is intended to study
collisions between a high-intensity optical laser and 16.5 GeV electrons from
the XFEL electron beam, as well as collisions between the optical laser and
high-energy secondary photons. The physics objective of LUXE are processes of
quantum electrodynamics (QED) at the strong-field frontier, where the
electromagnetic field of the laser is above the Schwinger limit. In this
regime, QED is non-perturbative. This manifests itself in the creation of
physical electron-positron pairs from the QED vacuum, similar to Hawking
radiation from black holes. LUXE intends to measure the positron production
rate in an unprecedented laser intensity regime. An overview of the LUXE
experimental setup and its challenges will be given, followed by a discussion
of the expected physics reach in the context of testing QED in the
non-perturbative regime.
| [
{
"created": "Mon, 8 Nov 2021 02:34:48 GMT",
"version": "v1"
},
{
"created": "Sun, 6 Mar 2022 19:54:24 GMT",
"version": "v2"
}
] | 2022-03-16 | [
[
"Huang",
"Shan",
"",
"for the LUXE Collaboration"
]
] | LUXE (Laser Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. LUXE is intended to study collisions between a high-intensity optical laser and 16.5 GeV electrons from the XFEL electron beam, as well as collisions between the optical laser and high-energy secondary photons. The physics objective of LUXE are processes of quantum electrodynamics (QED) at the strong-field frontier, where the electromagnetic field of the laser is above the Schwinger limit. In this regime, QED is non-perturbative. This manifests itself in the creation of physical electron-positron pairs from the QED vacuum, similar to Hawking radiation from black holes. LUXE intends to measure the positron production rate in an unprecedented laser intensity regime. An overview of the LUXE experimental setup and its challenges will be given, followed by a discussion of the expected physics reach in the context of testing QED in the non-perturbative regime. |
2406.00525 | Pasquale Di Bari | Pasquale Di Bari | Majorana mass generation, gravitational waves and cosmological tensions | 8 pages, 1 figure; talk given at EW Moriond 2024 (La Thuile, 24-31
March 2024) | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | A neutrino Majorana mass generation in the early universe might have left
imprints in cosmological observables. It can source the production of a
detectable stochastic background of primordial gravitational waves with a
spectrum that combines a contribution from a first order phase transition
production and from the vibration of global cosmic strings. An intriguing
possibility is given by the split seesaw model. In this case, in addition to
the traditional high scale seesaw, a low scale neutrino Majorana mass
generation can solve a potential primordial deuterium problem and ameliorate
the cosmological tensions of the $\Lambda$CDM model. At the same time, it can
also produce subdominant contribution to the NANOGrav signal of a stochastic
background of gravitational waves (GWs), in addition to the astrophysical
dominant contribution from supermassive black hole mergers.
| [
{
"created": "Sat, 1 Jun 2024 18:25:00 GMT",
"version": "v1"
}
] | 2024-06-04 | [
[
"Di Bari",
"Pasquale",
""
]
] | A neutrino Majorana mass generation in the early universe might have left imprints in cosmological observables. It can source the production of a detectable stochastic background of primordial gravitational waves with a spectrum that combines a contribution from a first order phase transition production and from the vibration of global cosmic strings. An intriguing possibility is given by the split seesaw model. In this case, in addition to the traditional high scale seesaw, a low scale neutrino Majorana mass generation can solve a potential primordial deuterium problem and ameliorate the cosmological tensions of the $\Lambda$CDM model. At the same time, it can also produce subdominant contribution to the NANOGrav signal of a stochastic background of gravitational waves (GWs), in addition to the astrophysical dominant contribution from supermassive black hole mergers. |
2310.03776 | Scott Tezlaf | S. V. Tezlaf | Significance of the negative binomial distribution in multiplicity
phenomena | 18 pages, 3 figures. Physica Scripta (2023) | null | 10.1088/1402-4896/acfead | null | hep-ph hep-th stat.ME | http://creativecommons.org/licenses/by-nc-nd/4.0/ | The negative binomial distribution (NBD) has been theorized to express a
scale-invariant property of many-body systems and has been consistently shown
to outperform other statistical models in both describing the multiplicity of
quantum-scale events in particle collision experiments and predicting the
prevalence of cosmological observables, such as the number of galaxies in a
region of space. Despite its widespread applicability and empirical success in
these contexts, a theoretical justification for the NBD from first principles
has remained elusive for fifty years. The accuracy of the NBD in modeling
hadronic, leptonic, and semileptonic processes is suggestive of a highly
general principle, which is yet to be understood. This study demonstrates that
a statistical event of the NBD can in fact be derived in a general context via
the dynamical equations of a canonical ensemble of particles in Minkowski
space. These results describe a fundamental feature of many-body systems that
is consistent with data from the ALICE and ATLAS experiments and provides an
explanation for the emergence of the NBD in these multiplicity observations.
Two methods are used to derive this correspondence: the Feynman path integral
and a hypersurface parametrization of a propagating ensemble.
| [
{
"created": "Thu, 5 Oct 2023 09:37:38 GMT",
"version": "v1"
}
] | 2023-10-09 | [
[
"Tezlaf",
"S. V.",
""
]
] | The negative binomial distribution (NBD) has been theorized to express a scale-invariant property of many-body systems and has been consistently shown to outperform other statistical models in both describing the multiplicity of quantum-scale events in particle collision experiments and predicting the prevalence of cosmological observables, such as the number of galaxies in a region of space. Despite its widespread applicability and empirical success in these contexts, a theoretical justification for the NBD from first principles has remained elusive for fifty years. The accuracy of the NBD in modeling hadronic, leptonic, and semileptonic processes is suggestive of a highly general principle, which is yet to be understood. This study demonstrates that a statistical event of the NBD can in fact be derived in a general context via the dynamical equations of a canonical ensemble of particles in Minkowski space. These results describe a fundamental feature of many-body systems that is consistent with data from the ALICE and ATLAS experiments and provides an explanation for the emergence of the NBD in these multiplicity observations. Two methods are used to derive this correspondence: the Feynman path integral and a hypersurface parametrization of a propagating ensemble. |
2011.03003 | Daniel Elander | Daniel Elander, Michele Frigerio, Marc Knecht, Jean-Loic Kneur | Holographic models of composite Higgs in the Veneziano limit. Part I.
Bosonic sector | Version published in JHEP. Additional discussion of the Veneziano
limit and of the dilaton lightness | J. High Energ. Phys. 2021, 182 (2021) | 10.1007/JHEP03(2021)182 | null | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study strongly-coupled, approximately scale-invariant gauge theories,
which develop a mass gap in the infrared. We argue that a large number of
fermion flavours is most suitable to provide an ultraviolet completion for the
composite Higgs scenario. The holographic approach allows to describe the
qualitative features of the non-perturbative dynamics in the Veneziano limit.
We introduce new bottom-up holographic models, which incorporate the
backreaction of flavour on the geometry, and show that this can correlate the
mass gap to the scale of flavour-symmetry breaking. We compute the mass
spectrum for the various composite bosonic states, and study its dependence on
the scaling dimension of the symmetry-breaking operators, as well as on the
number of flavours. The different regions with a light dilaton are critically
surveyed. We carefully assess the domain of validity of the holographic
approach, and compare it with lattice simulations and the Nambu--Jona-Lasinio
model.
| [
{
"created": "Thu, 5 Nov 2020 17:57:39 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Mar 2021 12:44:35 GMT",
"version": "v2"
}
] | 2021-03-25 | [
[
"Elander",
"Daniel",
""
],
[
"Frigerio",
"Michele",
""
],
[
"Knecht",
"Marc",
""
],
[
"Kneur",
"Jean-Loic",
""
]
] | We study strongly-coupled, approximately scale-invariant gauge theories, which develop a mass gap in the infrared. We argue that a large number of fermion flavours is most suitable to provide an ultraviolet completion for the composite Higgs scenario. The holographic approach allows to describe the qualitative features of the non-perturbative dynamics in the Veneziano limit. We introduce new bottom-up holographic models, which incorporate the backreaction of flavour on the geometry, and show that this can correlate the mass gap to the scale of flavour-symmetry breaking. We compute the mass spectrum for the various composite bosonic states, and study its dependence on the scaling dimension of the symmetry-breaking operators, as well as on the number of flavours. The different regions with a light dilaton are critically surveyed. We carefully assess the domain of validity of the holographic approach, and compare it with lattice simulations and the Nambu--Jona-Lasinio model. |
1308.5296 | Tom Mertens | T. Mertens and P. Taels | Evolution of Light-Like Wilson Loops with a Self-Intersection in Loop
Space | Correction of some small typos and small changes to the figures. To
be submitted for publication to Phys Lett B | Phys.Lett. B727 2013 563-567 | 10.1016/j.physletb.2013.11.011 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently, we proposed a general evolution equation for single quadrilateral
Wilson loop on the light-cone. In present work, we study the energy evolution
of a combination of two such loops that partially overlap or have a
self-intersection. We show that, for a class of geometric variations, then
evolution is consistent with our previous conjecture, and we are able to handle
the intricacies associated with the self-intersections and overlaps. This way,
a step forward is made towards the understanding of loop space, with the hope
of studying more complicated structures appearing in phenomenological relevant
objects, such as parton distributions.
| [
{
"created": "Sat, 24 Aug 2013 04:46:44 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Sep 2013 20:39:28 GMT",
"version": "v2"
}
] | 2014-01-14 | [
[
"Mertens",
"T.",
""
],
[
"Taels",
"P.",
""
]
] | Recently, we proposed a general evolution equation for single quadrilateral Wilson loop on the light-cone. In present work, we study the energy evolution of a combination of two such loops that partially overlap or have a self-intersection. We show that, for a class of geometric variations, then evolution is consistent with our previous conjecture, and we are able to handle the intricacies associated with the self-intersections and overlaps. This way, a step forward is made towards the understanding of loop space, with the hope of studying more complicated structures appearing in phenomenological relevant objects, such as parton distributions. |
1507.08795 | Abhijit Bhattacharyya Prof. | Abhijit Bhattacharyya, Sanjay K. Ghosh, Rajarshi Ray, Kinkar Saha and
Sudipa Upadhaya | Polyakov--Nambu--Jona-Lasinio model in finite volumes | null | Europhysics Letters, 116, 52001 (2016) | 10.1209/0295-5075/116/52001 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the 2+1 flavor Polyakov loop enhanced Nambu--Jona-Lasinio model in
a finite volume. The main objective is to check the volume scaling of
thermodynamic observables for various temperatures and chemical potentials. We
observe the possible violation of the scaling with system size in a
considerable window along the whole transition region in the $T-\mu_q$ plane.
| [
{
"created": "Fri, 31 Jul 2015 08:12:07 GMT",
"version": "v1"
},
{
"created": "Sun, 29 Jan 2017 07:19:18 GMT",
"version": "v2"
}
] | 2017-01-31 | [
[
"Bhattacharyya",
"Abhijit",
""
],
[
"Ghosh",
"Sanjay K.",
""
],
[
"Ray",
"Rajarshi",
""
],
[
"Saha",
"Kinkar",
""
],
[
"Upadhaya",
"Sudipa",
""
]
] | We discuss the 2+1 flavor Polyakov loop enhanced Nambu--Jona-Lasinio model in a finite volume. The main objective is to check the volume scaling of thermodynamic observables for various temperatures and chemical potentials. We observe the possible violation of the scaling with system size in a considerable window along the whole transition region in the $T-\mu_q$ plane. |
hep-ph/0612295 | Raymond R. Volkas | Raymond R. Volkas | The brane as a Higgs domain wall: ideas and issues | 4 pages. Invited talk at Susy06. To appear in the proceedings | AIPConf.Proc.903:419-422,2007 | 10.1063/1.2735213 | null | hep-ph | null | The most obvious field-theoretic model for a brane is a scalar field domain
wall or kink. I discuss how this idea can be connected with spontaneous
internal symmetry breaking via a mechanism called the ``clash of symmetries''.
Compatibility with Randall and Sundrum's warped metric alternative to
compactification is then demonstrated. I end with brief remarks about open
questions.
| [
{
"created": "Fri, 22 Dec 2006 03:31:13 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Volkas",
"Raymond R.",
""
]
] | The most obvious field-theoretic model for a brane is a scalar field domain wall or kink. I discuss how this idea can be connected with spontaneous internal symmetry breaking via a mechanism called the ``clash of symmetries''. Compatibility with Randall and Sundrum's warped metric alternative to compactification is then demonstrated. I end with brief remarks about open questions. |
1003.5725 | Maxim Perelstein | Maxim Perelstein and Yong-Hui Qi | Topological Interactions in the Higgsless Model at the LHC | 18 pages, 8 figures. Discussion of Drell-Yan production process added
in v3. This is the final version to appear in Physical Review D | Phys.Rev.D82:015004,2010 | 10.1103/PhysRevD.82.015004 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Topological quantum interactions, namely Chern-Simons terms and global
Wess-Zumino terms, arise naturally in theories with extra dimensions of space
compactified on orbifolds. If the extra dimensions become manifest at the TeV
scale, experiments at the Large Hadron Collider (LHC) could observe signatures
of topological interactions. Decays of Kaluza-Klein excitations of neutral
electroweak gauge bosons into pairs of neutral Standard Model gauge bosons, ZZ
and Z+photon, would provide a clean signature, since such decays do not occur
at tree level. In this paper, we investigate the prospects for discovering such
decays at the LHC, in the context of the Higgsless model of electroweak
symmetry breaking. We identify the form of the relevant topological
interactions, and estimate their strength. We find that in the minimal version
of the model, the signal may be observed with about 100 inverse fb of data at
the LHC using the Drell-Yan production process of the Kaluza-Klein gauge
bosons. In addition, it is likely that the ultraviolet completion of the model
would contain additional massive fermions, which can significantly enhance the
signal. With two additional fermion multiplets, observation of the topological
decay modes at the 3-sigma level would be possible with about 100 inverse fb of
data using the highly model-independent vector boson fusion production channel.
| [
{
"created": "Tue, 30 Mar 2010 03:17:05 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Apr 2010 19:40:24 GMT",
"version": "v2"
},
{
"created": "Thu, 8 Jul 2010 17:48:56 GMT",
"version": "v3"
}
] | 2014-11-20 | [
[
"Perelstein",
"Maxim",
""
],
[
"Qi",
"Yong-Hui",
""
]
] | Topological quantum interactions, namely Chern-Simons terms and global Wess-Zumino terms, arise naturally in theories with extra dimensions of space compactified on orbifolds. If the extra dimensions become manifest at the TeV scale, experiments at the Large Hadron Collider (LHC) could observe signatures of topological interactions. Decays of Kaluza-Klein excitations of neutral electroweak gauge bosons into pairs of neutral Standard Model gauge bosons, ZZ and Z+photon, would provide a clean signature, since such decays do not occur at tree level. In this paper, we investigate the prospects for discovering such decays at the LHC, in the context of the Higgsless model of electroweak symmetry breaking. We identify the form of the relevant topological interactions, and estimate their strength. We find that in the minimal version of the model, the signal may be observed with about 100 inverse fb of data at the LHC using the Drell-Yan production process of the Kaluza-Klein gauge bosons. In addition, it is likely that the ultraviolet completion of the model would contain additional massive fermions, which can significantly enhance the signal. With two additional fermion multiplets, observation of the topological decay modes at the 3-sigma level would be possible with about 100 inverse fb of data using the highly model-independent vector boson fusion production channel. |
1602.07214 | Yuta Orikasa | P. Ko, Takaaki Nomura, Hiroshi Okada, Yuta Orikasa | Confronting a New Three-loop Seesaw Model with the 750 GeV Diphoton
Excess | 34 pages, 9 figures, 1 table. arXiv admin note: text overlap with
arXiv:1601.07339, arXiv:1601.04516, version to appear in PRD | Phys. Rev. D 94, 013009 (2016) | 10.1103/PhysRevD.94.013009 | KIAS-P16018 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new type of radiative neutrino model with a local hidden $U(1)$
symmetry, in which neutrino masses are induced at the three loop level, and
discuss the muon anomalous magnetic moment, and dark matter candidates therein.
By allowing the hypercharges larger than 3/2 for new fields that contribute to
the neutrino masses and making them decay into the standard model fields
appropriately, we introduce a lot of new particles with multiple electrical
charges in a natural manner. As a by-product, we can accommodate the 750 GeV
diphoton excess depending on the hypercharge quantum numbers of new fields
responsible for the neutrino masses at the three loop level.
| [
{
"created": "Tue, 23 Feb 2016 15:56:42 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Jul 2016 06:03:45 GMT",
"version": "v2"
}
] | 2016-07-20 | [
[
"Ko",
"P.",
""
],
[
"Nomura",
"Takaaki",
""
],
[
"Okada",
"Hiroshi",
""
],
[
"Orikasa",
"Yuta",
""
]
] | We propose a new type of radiative neutrino model with a local hidden $U(1)$ symmetry, in which neutrino masses are induced at the three loop level, and discuss the muon anomalous magnetic moment, and dark matter candidates therein. By allowing the hypercharges larger than 3/2 for new fields that contribute to the neutrino masses and making them decay into the standard model fields appropriately, we introduce a lot of new particles with multiple electrical charges in a natural manner. As a by-product, we can accommodate the 750 GeV diphoton excess depending on the hypercharge quantum numbers of new fields responsible for the neutrino masses at the three loop level. |
1807.06245 | Wolfgang Lucha | Thomas Hilger, Mar\'ia G\'omez-Rocha, Andreas Krassnigg, Wolfgang
Lucha | Global Dyson-Schwinger-Bethe-Salpeter Approach to Mesons with Open
Flavour | 5 pages, 6 figures, contributed to "QCD@Work 2018 - International
Workshop on Quantum Chromodynamics: Theory and Experiment" (25 - 28 June
2018, Matera, Italy) | EPJ Web of Conferences 192, 00038 (2018) | 10.1051/epjconf/201819200038 | HEPHY-PUB 1003/18 (2018) | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Exploiting an interplay of the Bethe-Salpeter equation enabling us to regard
mesons as bound states of quark and antiquark and the Dyson-Schwinger equation
controlling the dressed quark propagator, we amend existing studies of
quarkonia by a comprehensive description of open-flavour mesons composed of all
conceivable combinations of quark flavour. Employing throughout a fixed set of
model parameters, we predict some basic characteristics of these mesons, i.e.,
their masses, leptonic decay constants and corresponding in-hadron condensates
entering in a generalized formulation of the Gell-Mann-Oakes-Renner relation.
| [
{
"created": "Tue, 17 Jul 2018 06:49:37 GMT",
"version": "v1"
}
] | 2019-06-03 | [
[
"Hilger",
"Thomas",
""
],
[
"Gómez-Rocha",
"María",
""
],
[
"Krassnigg",
"Andreas",
""
],
[
"Lucha",
"Wolfgang",
""
]
] | Exploiting an interplay of the Bethe-Salpeter equation enabling us to regard mesons as bound states of quark and antiquark and the Dyson-Schwinger equation controlling the dressed quark propagator, we amend existing studies of quarkonia by a comprehensive description of open-flavour mesons composed of all conceivable combinations of quark flavour. Employing throughout a fixed set of model parameters, we predict some basic characteristics of these mesons, i.e., their masses, leptonic decay constants and corresponding in-hadron condensates entering in a generalized formulation of the Gell-Mann-Oakes-Renner relation. |
2212.14361 | Juri Smirnov | Juri Smirnov | Dark Matter Bound States: A Window into the Early Universe | Contribution to the proceedings series based on a plenary talk at the
iDM2022 conference in Vienna. 10 pages, 3 figures | null | 10.21468/SciPostPhysProc | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Despite significant experimental sensitivity to point-like, weakly
interacting particles at the electroweak mass scale, dark matter has not been
found yet. This could hint at a more complex dark sector with multiple states
or composite dark particles, much like the complexity of the standard model.
Currently, our experimental sensitivity to such scenarios is limited by a lack
of theoretical understanding. The investigation of Dark Matter systems with
unstable or stable bound states provides a playground that leads to the
development of important tools needed for the understanding of dark sectors
with complex phenomena and allows to experimentally test well-motivated DM
scenarios.
| [
{
"created": "Thu, 29 Dec 2022 16:21:49 GMT",
"version": "v1"
}
] | 2023-01-02 | [
[
"Smirnov",
"Juri",
""
]
] | Despite significant experimental sensitivity to point-like, weakly interacting particles at the electroweak mass scale, dark matter has not been found yet. This could hint at a more complex dark sector with multiple states or composite dark particles, much like the complexity of the standard model. Currently, our experimental sensitivity to such scenarios is limited by a lack of theoretical understanding. The investigation of Dark Matter systems with unstable or stable bound states provides a playground that leads to the development of important tools needed for the understanding of dark sectors with complex phenomena and allows to experimentally test well-motivated DM scenarios. |
hep-ph/0701115 | Lyakhov Konstantin | K.A.Lyakhov | Baryon kinetic energy loss in the color flux tube model | 13 pages, 2 figures | Phys. Rev. C 84, (2011), 055206 | 10.1103/PhysRevC.84.055206 | null | hep-ph | null | This article generalizes Schwinger's mechanism for particles production in
the arbitrary finite field volume. McLerran-Venugopolan(MV) model and iterative
solution of DGLAP equation in the double leading log approximation for small x
gluon distribution function were used to derive the new formula for initial
chromofield energy density. This initial chromofield energy is distributed
among color neutral clusters or strings of different length. This strings are
stretched by receding nucleus. From the proposed mechanism of string
fragmentation or color field decay based on exact solution of Dirac equation in
the different finite volume, the new formulae for esimated baryon kinetic
energy loss and rapidity spectrum of produced partons were derived.
| [
{
"created": "Mon, 15 Jan 2007 19:10:28 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Jul 2007 17:08:10 GMT",
"version": "v2"
}
] | 2023-12-04 | [
[
"Lyakhov",
"K. A.",
""
]
] | This article generalizes Schwinger's mechanism for particles production in the arbitrary finite field volume. McLerran-Venugopolan(MV) model and iterative solution of DGLAP equation in the double leading log approximation for small x gluon distribution function were used to derive the new formula for initial chromofield energy density. This initial chromofield energy is distributed among color neutral clusters or strings of different length. This strings are stretched by receding nucleus. From the proposed mechanism of string fragmentation or color field decay based on exact solution of Dirac equation in the different finite volume, the new formulae for esimated baryon kinetic energy loss and rapidity spectrum of produced partons were derived. |
hep-ph/0406158 | Yuli Shabelski | F.Bopp, Yu.M.Shabelski | Baryon Number Transfer in High Energy $hp$ Collisions | 10 pages, 7 figures, references added | Phys.Atom.Nucl. 68 (2005) 2093-2099; Yad.Fiz. 68 (2005) 2155-2161 | 10.1134/1.2149088 | null | hep-ph | null | The process of baryon number transfer due to string junction propagation in
rapidity is considered. It has a significant effect in the net baryon
production in $pp$ collisions at mid-rapidities and an even larger effect in
the forward hemisphere in the cases of $\pi p$ and $\gamma p$ interactions. The
results of numerical calculations in the framework of the Quark-Gluon String
Model are in reasonable agreement with the data with the same parameter values
for different energies.
| [
{
"created": "Tue, 15 Jun 2004 12:06:37 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Jun 2004 09:33:04 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Bopp",
"F.",
""
],
[
"Shabelski",
"Yu. M.",
""
]
] | The process of baryon number transfer due to string junction propagation in rapidity is considered. It has a significant effect in the net baryon production in $pp$ collisions at mid-rapidities and an even larger effect in the forward hemisphere in the cases of $\pi p$ and $\gamma p$ interactions. The results of numerical calculations in the framework of the Quark-Gluon String Model are in reasonable agreement with the data with the same parameter values for different energies. |
hep-ph/0203168 | Kamila Kowalska | Kamila Kowalska (Institute of Theoretical Physics, Warsaw University,
Poland) | Neutrino masses and unification of the gauge and Yukawa couplings | 11 pages | Acta Phys.Polon.B33:1823,2002 | null | IFT-02/11 | hep-ph | null | There is a convincing experimental evidence that neutrinos are massive.
Therefore we investigate the influence of the neutrino masses on the
unification of gauge and Yukawa couplings in the framework of the Minimal
Supersymmetric Standard Model. We estimate the contribution of the neutrino
Yukawa coupling to the gauge and Yukawa coupling unification. We find that in
the case of the gauge coupling unification the effect of massive neutrinos is
small and can be neglected. It appears to be much more significant, if we
explore Y_{b} and Y_{tau} equality at the GUT scale. The neutrino contribution
can change that relation even by ~12%.
| [
{
"created": "Mon, 18 Mar 2002 14:29:45 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Mar 2002 13:54:54 GMT",
"version": "v2"
},
{
"created": "Fri, 22 Mar 2002 11:15:06 GMT",
"version": "v3"
}
] | 2014-11-17 | [
[
"Kowalska",
"Kamila",
"",
"Institute of Theoretical Physics, Warsaw University,\n Poland"
]
] | There is a convincing experimental evidence that neutrinos are massive. Therefore we investigate the influence of the neutrino masses on the unification of gauge and Yukawa couplings in the framework of the Minimal Supersymmetric Standard Model. We estimate the contribution of the neutrino Yukawa coupling to the gauge and Yukawa coupling unification. We find that in the case of the gauge coupling unification the effect of massive neutrinos is small and can be neglected. It appears to be much more significant, if we explore Y_{b} and Y_{tau} equality at the GUT scale. The neutrino contribution can change that relation even by ~12%. |
1309.5736 | David Greynat | Giancarlo D'Ambrosio, David Greynat and Gr\'egory Vulvert | Standard Model and New Physics contributions to $K_L$ and $K_S$ into
four leptons | Improvements of the text and references added | Eur. Phys. J. C (2013) 73:2678 | 10.1140/epjc/s10052-013-2678-1 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the $K_L$ and $K_S$ decays into four leptons ($e\bar{e}e\bar{e}, \,
\mu\bar{\mu}\mu\bar{\mu},\, e\bar{e}\mu\bar{\mu}$) where we use a form factor
motivated by vector meson dominance, and show the dependence of the branching
ratios and spectra from the slopes. A precise determination of short distance
contribution to $K_L\to \mu\mu$ is affected by our ignorance on the sign of the
amplitude $\mathcal{A}(K_L\to \gamma\gamma)$ but we show a possibility to
measure the sign of this amplitude by studying $K_L$ and $K_S$ decays in four
leptons. We also investigate the effect of New Physics contributions for these
decays.
| [
{
"created": "Mon, 23 Sep 2013 09:18:12 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Sep 2013 09:07:27 GMT",
"version": "v2"
},
{
"created": "Thu, 28 Nov 2013 12:15:34 GMT",
"version": "v3"
}
] | 2014-04-02 | [
[
"D'Ambrosio",
"Giancarlo",
""
],
[
"Greynat",
"David",
""
],
[
"Vulvert",
"Grégory",
""
]
] | We study the $K_L$ and $K_S$ decays into four leptons ($e\bar{e}e\bar{e}, \, \mu\bar{\mu}\mu\bar{\mu},\, e\bar{e}\mu\bar{\mu}$) where we use a form factor motivated by vector meson dominance, and show the dependence of the branching ratios and spectra from the slopes. A precise determination of short distance contribution to $K_L\to \mu\mu$ is affected by our ignorance on the sign of the amplitude $\mathcal{A}(K_L\to \gamma\gamma)$ but we show a possibility to measure the sign of this amplitude by studying $K_L$ and $K_S$ decays in four leptons. We also investigate the effect of New Physics contributions for these decays. |
0902.3570 | Alfredo Valcarce | J. Vijande, G. Krein, A. Valcarce | Screened potential and quarkonia properties at high temperatures | 9 pages, 11 figures. Accepted for publication ijn Eur. Phys. J. A | Eur.Phys.J.A40:89-97,2009 | 10.1140/epja/i2008-10736-9 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a quark model calculation of the quarkonia $b\overline{b}$ and
$c\overline{c}$ spectra using smooth and sudden string breaking potentials. The
screening parameter is scale dependent and can be related to an effective
running gluon mass that has a finite infrared fixed point. A temperature
dependence for the screening mass is motivated by lattice QCD simulations at
finite temperature. Qualitatively different results are obtained for quarkonia
properties close to a critical value of the deconfining temperature when a
smooth or a sudden string breaking potential is used. In particular, with a
sudden string breaking potential quarkonia radii remain almost independent of
the temperature up to the critical point, only well above the critical point
the radii increase significantly. Such a behavior will impact the phenomenology
of quarkonia interactions in medium, in particular for scattering dissociation
processes.
| [
{
"created": "Fri, 20 Feb 2009 12:34:26 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Vijande",
"J.",
""
],
[
"Krein",
"G.",
""
],
[
"Valcarce",
"A.",
""
]
] | We perform a quark model calculation of the quarkonia $b\overline{b}$ and $c\overline{c}$ spectra using smooth and sudden string breaking potentials. The screening parameter is scale dependent and can be related to an effective running gluon mass that has a finite infrared fixed point. A temperature dependence for the screening mass is motivated by lattice QCD simulations at finite temperature. Qualitatively different results are obtained for quarkonia properties close to a critical value of the deconfining temperature when a smooth or a sudden string breaking potential is used. In particular, with a sudden string breaking potential quarkonia radii remain almost independent of the temperature up to the critical point, only well above the critical point the radii increase significantly. Such a behavior will impact the phenomenology of quarkonia interactions in medium, in particular for scattering dissociation processes. |
hep-ph/0305165 | A. Cooper-Sarkar | A.M.Cooper-Sarkar and R.C.E.Devenish | The rise and fall of F_2 at low x | 16 pages, 11 figues. To appear in the special edition of Acta Physica
Polonica to celebrate the 65th birthday of Prof. Jan Kwiecinski | Acta Phys.Polon.B34:2911-2928,2003 | null | null | hep-ph | null | A short personal account is given of the impact of HERA data and the
influence of Jan Kwiecinski on low x physics
| [
{
"created": "Thu, 15 May 2003 13:26:53 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Cooper-Sarkar",
"A. M.",
""
],
[
"Devenish",
"R. C. E.",
""
]
] | A short personal account is given of the impact of HERA data and the influence of Jan Kwiecinski on low x physics |
hep-ph/0006070 | Alexei Nefediev | Yu.S.Kalashnikova, A.V.Nefediev (ITEP,Moscow) | Strong decays and Adler selfconsistency condition in two-dimensional QCD | LaTeX2e, 10 pages, 4 eps pictures, comment and one reference added | Phys.Lett. B487 (2000) 371-378 | 10.1016/S0370-2693(00)00828-5 | null | hep-ph | null | Strong mesonic decays are studied in the framework of the 't Hooft model for
the two-dimensional QCD in the axial gauge. Special attention is payed to the
processes with pions in the final state involved and the low energy theorems
have been checked including the "Adler zero". It is demonstrated explicitly
that in the chiral limit any three-meson decay amplitude with at least one pion
vertex vanishes identically for any values of the external momenta. Ward
identities for the dressed vector and axial-vector currents vertices are
identified and their relationship to the pionic vertex are discussed.
| [
{
"created": "Thu, 8 Jun 2000 08:17:38 GMT",
"version": "v1"
},
{
"created": "Wed, 23 Aug 2000 11:17:10 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kalashnikova",
"Yu. S.",
"",
"ITEP,Moscow"
],
[
"Nefediev",
"A. V.",
"",
"ITEP,Moscow"
]
] | Strong mesonic decays are studied in the framework of the 't Hooft model for the two-dimensional QCD in the axial gauge. Special attention is payed to the processes with pions in the final state involved and the low energy theorems have been checked including the "Adler zero". It is demonstrated explicitly that in the chiral limit any three-meson decay amplitude with at least one pion vertex vanishes identically for any values of the external momenta. Ward identities for the dressed vector and axial-vector currents vertices are identified and their relationship to the pionic vertex are discussed. |
0901.1619 | Sujoy Poddar | Amitava Datta and Sujoy Poddar | Probing R-parity violating models of neutrino mass at the LHC via top
squark decays | 19 pages, 1 Figure and 11 Tables | Phys.Rev.D79:075021,2009 | 10.1103/PhysRevD.79.075021 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that the R-parity violating decays of the lighter top squarks
(${\widetilde t}_1$) triggered by the lepton number violating couplings
$\lambda^{\prime}_{i33}$, where the lepton family index i = 1-3, can be
observed at the LHC via the dilepton di-jet channel even if the coupling is as
small as 10$^{-4}$ or 10$^{-5}$, which is the case in several models of
neutrino mass, provided it is the next lightest supersymmetric particle(NLSP)
the lightest neutralino being the lightest supersymmetric particle(LSP). We
have first obtained a fairly model independent estimate of the minimum
observable value of the parameter ($P_{ij} \equiv BR(\widetilde t \to l_i^+ b)
\times BR(\widetilde t^* \to l_j^- \bar b$)) at the LHC for an integrated
luminosity of 10fb$^{-1}$ as a function of $\mlstop$ by a standard Pythia based
analysis. We have then computed the parameter $P_{ij}$ in several
representative models of neutrino mass constrained by the neutrino oscillation
data and have found that the theoretical predictions are above the estimated
minimum observable levels for a wide region of the parameter space.
| [
{
"created": "Mon, 12 Jan 2009 17:26:52 GMT",
"version": "v1"
}
] | 2009-11-06 | [
[
"Datta",
"Amitava",
""
],
[
"Poddar",
"Sujoy",
""
]
] | It is shown that the R-parity violating decays of the lighter top squarks (${\widetilde t}_1$) triggered by the lepton number violating couplings $\lambda^{\prime}_{i33}$, where the lepton family index i = 1-3, can be observed at the LHC via the dilepton di-jet channel even if the coupling is as small as 10$^{-4}$ or 10$^{-5}$, which is the case in several models of neutrino mass, provided it is the next lightest supersymmetric particle(NLSP) the lightest neutralino being the lightest supersymmetric particle(LSP). We have first obtained a fairly model independent estimate of the minimum observable value of the parameter ($P_{ij} \equiv BR(\widetilde t \to l_i^+ b) \times BR(\widetilde t^* \to l_j^- \bar b$)) at the LHC for an integrated luminosity of 10fb$^{-1}$ as a function of $\mlstop$ by a standard Pythia based analysis. We have then computed the parameter $P_{ij}$ in several representative models of neutrino mass constrained by the neutrino oscillation data and have found that the theoretical predictions are above the estimated minimum observable levels for a wide region of the parameter space. |
hep-ph/0611355 | Markus H. Thoma | Purnendu Chakraborty, Munshi Golam Mustafa, Markus H. Thoma | Energy gain of heavy quarks by fluctuations in the QGP | 6 pages, 4 figures, extended version, accepted for publication in
Phys. Rev. C | Phys.Rev.C75:064908,2007 | 10.1103/PhysRevC.75.064908 | null | hep-ph nucl-th | null | The collisional energy gain of a heavy quark due to chromo-electromagnetic
field fluctuations in a quark-gluon plasma is investigated. The field
fluctuations lead to an energy gain of the quark for all temperatures and
velocities. The net effect is a reduction of the collisional energy loss by
15-40% for parameters relevant at RHIC energies.
| [
{
"created": "Tue, 28 Nov 2006 15:40:55 GMT",
"version": "v1"
},
{
"created": "Fri, 11 May 2007 13:58:38 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Chakraborty",
"Purnendu",
""
],
[
"Mustafa",
"Munshi Golam",
""
],
[
"Thoma",
"Markus H.",
""
]
] | The collisional energy gain of a heavy quark due to chromo-electromagnetic field fluctuations in a quark-gluon plasma is investigated. The field fluctuations lead to an energy gain of the quark for all temperatures and velocities. The net effect is a reduction of the collisional energy loss by 15-40% for parameters relevant at RHIC energies. |
hep-ph/9311265 | null | T.G. Rizzo | Model Dependence of $W_R$ Searches at the Tevatron | LaTex, 13 pages, 11 figures (not included), ANL-HEP-PR-93-87 | Phys.Rev.D50:325-330,1994 | 10.1103/PhysRevD.50.325 | null | hep-ph | null | We explore the sensitivity of the on-going Tevatron search for charged,
right-handed gauge bosons, $W_R^{\pm}$, to various model dependent assumptions
such as the magnitude of the $SU(2)_R$ gauge coupling, the values of the
right-handed Kobayashi-Maskawa mixing matrix elements, $(V_R)_{ij}$, and the
nature of the right-handed neutrino. These results also have important
implications for HERA searches for right-handed currents.
| [
{
"created": "Wed, 10 Nov 1993 12:46:04 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Rizzo",
"T. G.",
""
]
] | We explore the sensitivity of the on-going Tevatron search for charged, right-handed gauge bosons, $W_R^{\pm}$, to various model dependent assumptions such as the magnitude of the $SU(2)_R$ gauge coupling, the values of the right-handed Kobayashi-Maskawa mixing matrix elements, $(V_R)_{ij}$, and the nature of the right-handed neutrino. These results also have important implications for HERA searches for right-handed currents. |
1003.0324 | Yuji Kajiyama | Yuji Kajiyama, Shaaban Khalil, Hiroshi Okada and Ernest Ma | Gauged B-L Leptogenesis | 4 pages, 2 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new leptogenesis scenario in a gauged $B-L$ model with
supersymmetry at the TeV energy scale. Instead of relying on the very small
Yukawa couplings of the singlet neutrinos $N^c$ to generate the observed baryon
asymmetry of the Universe, which requires a very large resonance enhancement,
their $B-L$ gauge interactions are invoked. Successful leptogenesis is then
possible if a particular scalar bilinear $\tilde N^c \tilde N^c$ term is
disallowed.
| [
{
"created": "Mon, 1 Mar 2010 12:00:17 GMT",
"version": "v1"
}
] | 2010-03-02 | [
[
"Kajiyama",
"Yuji",
""
],
[
"Khalil",
"Shaaban",
""
],
[
"Okada",
"Hiroshi",
""
],
[
"Ma",
"Ernest",
""
]
] | We propose a new leptogenesis scenario in a gauged $B-L$ model with supersymmetry at the TeV energy scale. Instead of relying on the very small Yukawa couplings of the singlet neutrinos $N^c$ to generate the observed baryon asymmetry of the Universe, which requires a very large resonance enhancement, their $B-L$ gauge interactions are invoked. Successful leptogenesis is then possible if a particular scalar bilinear $\tilde N^c \tilde N^c$ term is disallowed. |
1204.5453 | Fuminobu Takahashi | Kwang Sik Jeong and Fuminobu Takahashi | Anarchy and Leptogenesis | 29 pages, 6 figures. v2: figures and references added. v3: published
in JHEP | JHEP07(2012)170 | 10.1007/JHEP07(2012)170 | TU-905; IPMU12-0071 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study if leptogenesis works successfully together with the neutrino mass
anarchy hypothesis. We find that the predicted neutrino mass spectrum is
sensitive to the reheating temperature or the inflaton mass, while the
distributions of the neutrino mixing angles and CP violation phases remain
intact as determined by the invariant Haar measure of U(3). In the case of
thermal leptogenesis, the light neutrino mass distribution agrees well with the
observations if the reheating temperature is O(10^{9-11}) GeV. The mass
spectrum of the right-handed neutrinos and the neutrino Yukawa matrix exhibit a
certain pattern, as a result of the competition between random matrices with
elements of order unity and the wash-out effect. Non-thermal leptogenesis is
consistent with observation only if the inflaton mass is larger than or
comparable to the typical right-handed neutrino mass scale. Cosmological
implications are discussed in connection with the 125GeV Higgs boson mass.
| [
{
"created": "Tue, 24 Apr 2012 18:03:50 GMT",
"version": "v1"
},
{
"created": "Thu, 10 May 2012 05:16:42 GMT",
"version": "v2"
},
{
"created": "Thu, 2 Aug 2012 00:52:38 GMT",
"version": "v3"
}
] | 2012-08-03 | [
[
"Jeong",
"Kwang Sik",
""
],
[
"Takahashi",
"Fuminobu",
""
]
] | We study if leptogenesis works successfully together with the neutrino mass anarchy hypothesis. We find that the predicted neutrino mass spectrum is sensitive to the reheating temperature or the inflaton mass, while the distributions of the neutrino mixing angles and CP violation phases remain intact as determined by the invariant Haar measure of U(3). In the case of thermal leptogenesis, the light neutrino mass distribution agrees well with the observations if the reheating temperature is O(10^{9-11}) GeV. The mass spectrum of the right-handed neutrinos and the neutrino Yukawa matrix exhibit a certain pattern, as a result of the competition between random matrices with elements of order unity and the wash-out effect. Non-thermal leptogenesis is consistent with observation only if the inflaton mass is larger than or comparable to the typical right-handed neutrino mass scale. Cosmological implications are discussed in connection with the 125GeV Higgs boson mass. |
hep-ph/9612254 | Concha Gonzalez-Garcia | O.J.P. Eboli, M.C. Gonzalez-Garcia, and J.K. Mizukoshi | Z Physics Constraints on Vector Leptoquarks | 15 pages, revtex, 3 figures included | Phys.Lett.B396:238-244,1997 | 10.1016/S0370-2693(97)00123-8 | FTUV/96-82; IFIC/96-91; IFUSP-P 1251 | hep-ph | null | We analyze the constraints on vector leptoquarks coming from radiative
corrections to $Z$ physics. We perform a global fitting to the LEP data
including the oblique and non-universal contributions of the most general
effective Lagrangian for vector leptoquarks, which exhibits the $SU(2)_L \times
U(1)_Y$ gauge invariance. We show that the $Z$ physics leads to stronger bounds
on second and third generation vectors leptoquarks than the ones obtained from
low energy and the current collider experiments.
| [
{
"created": "Wed, 4 Dec 1996 16:32:52 GMT",
"version": "v1"
}
] | 2011-01-25 | [
[
"Eboli",
"O. J. P.",
""
],
[
"Gonzalez-Garcia",
"M. C.",
""
],
[
"Mizukoshi",
"J. K.",
""
]
] | We analyze the constraints on vector leptoquarks coming from radiative corrections to $Z$ physics. We perform a global fitting to the LEP data including the oblique and non-universal contributions of the most general effective Lagrangian for vector leptoquarks, which exhibits the $SU(2)_L \times U(1)_Y$ gauge invariance. We show that the $Z$ physics leads to stronger bounds on second and third generation vectors leptoquarks than the ones obtained from low energy and the current collider experiments. |
1402.0666 | Felipe J. Llanes-Estrada | Antonio Dobado (contact author), Rafael L. Delgado and Felipe J.
Llanes-Estrada (Univ. Complutense Madrid) | Strongly Interacting Electroweak Symmetry Breaking Sector with a
Higgs-like light scalar | Delivered at the II Russian-Spanish Congress "Particle and Nuclear
Physics at all Scales and Cosmology" Institute of Cosmos Sciences,
Saint-Petersburg, October 1-4, 2013. To be published (AIP proc.) | null | 10.1063/1.4891127 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The apparent finding of a 125-GeV light Higgs boson closes unitarity of the
minimal Standard Model (SM), that is weakly interacting: this is an exceptional
feature not generally true if new physics exists beyond the mass gap found at
the LHC up to 700 GeV. Such new physics induces departures of the low-energy
dynamics for the minimal electroweak symmetry-breaking sector, with three
Goldstone bosons (related to longitudinal W bosons) and one light scalar, from
the SM couplings. We calculate the scattering amplitudes among these four
particles and their partial-wave projections in effective theory. For this we
employ the Electroweak Chiral Lagrangian extended by one light scalar and carry
out the complete one-loop computation at high energy including the counterterms
needed for perturbative renormalization, of dimension eight. For most of
parameter space, the scattering is strongly interacting (with the SM a
remarkable exception). We therefore explore various unitarization methods, that
can already be applied to the tree-level $W_L W_L$ amplitude; we find and study
a natural second sigma-like scalar pole there.
| [
{
"created": "Tue, 4 Feb 2014 09:11:54 GMT",
"version": "v1"
}
] | 2015-04-17 | [
[
"Dobado",
"Antonio",
"",
"contact author"
],
[
"Delgado",
"Rafael L.",
"",
"Univ. Complutense Madrid"
],
[
"Llanes-Estrada",
"Felipe J.",
"",
"Univ. Complutense Madrid"
]
] | The apparent finding of a 125-GeV light Higgs boson closes unitarity of the minimal Standard Model (SM), that is weakly interacting: this is an exceptional feature not generally true if new physics exists beyond the mass gap found at the LHC up to 700 GeV. Such new physics induces departures of the low-energy dynamics for the minimal electroweak symmetry-breaking sector, with three Goldstone bosons (related to longitudinal W bosons) and one light scalar, from the SM couplings. We calculate the scattering amplitudes among these four particles and their partial-wave projections in effective theory. For this we employ the Electroweak Chiral Lagrangian extended by one light scalar and carry out the complete one-loop computation at high energy including the counterterms needed for perturbative renormalization, of dimension eight. For most of parameter space, the scattering is strongly interacting (with the SM a remarkable exception). We therefore explore various unitarization methods, that can already be applied to the tree-level $W_L W_L$ amplitude; we find and study a natural second sigma-like scalar pole there. |
hep-ph/0405206 | Bachir Moussallam | B. Ananthanarayan and B. Moussallam | Four-point correlator constraints on electromagnetic chiral parameters
and resonance effective Lagrangians | 42 pages, 1 figure. v2: references added | JHEP 0406:047,2004 | 10.1088/1126-6708/2004/06/047 | IISc-CHEP-5/04 IPNO-DR-04/05 | hep-ph | null | We pursue the analysis of a set of generalized DGMLY sum rules for the
electromagnetic chiral parameters at order $e^2p^2$ and discuss implications
for effective Lagrangians with resonances. We exploit a formalism in which
charge spurions are introduced and treated as sources. We show that no
inconsistency arises from anomalies up to quadratic order in the spurions. We
focus on the sum rules associated with QCD 4-point correlators which were not
analyzed in detail before. Convergence properties of the sum rules are deduced
from a general analysis of the form of the counterterms in the presence of
electromagnetic spurions. Following the approach in which vector and
axial-vector resonances are described with antisymmetric tensor fields and have
a chiral order, we show that the convergence constraints are violated at chiral
order four and can be satisfied by introducing a set of terms of order six. The
relevant couplings get completely and uniquely determined from a set of
generalized Weinberg sum-rule relations. An update on the corrections to
Dashen's low-energy theorem is given.
| [
{
"created": "Fri, 21 May 2004 10:55:50 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Jun 2004 13:45:53 GMT",
"version": "v2"
}
] | 2010-02-03 | [
[
"Ananthanarayan",
"B.",
""
],
[
"Moussallam",
"B.",
""
]
] | We pursue the analysis of a set of generalized DGMLY sum rules for the electromagnetic chiral parameters at order $e^2p^2$ and discuss implications for effective Lagrangians with resonances. We exploit a formalism in which charge spurions are introduced and treated as sources. We show that no inconsistency arises from anomalies up to quadratic order in the spurions. We focus on the sum rules associated with QCD 4-point correlators which were not analyzed in detail before. Convergence properties of the sum rules are deduced from a general analysis of the form of the counterterms in the presence of electromagnetic spurions. Following the approach in which vector and axial-vector resonances are described with antisymmetric tensor fields and have a chiral order, we show that the convergence constraints are violated at chiral order four and can be satisfied by introducing a set of terms of order six. The relevant couplings get completely and uniquely determined from a set of generalized Weinberg sum-rule relations. An update on the corrections to Dashen's low-energy theorem is given. |
hep-ph/9408309 | Dremin | I.M. Dremin | Multiplicity Distributions in QCD at Very High Energies | 4 pages, no Figs. Abbreviated version of the talk given at 8th
International conf. on Very High Energy Cosmic Ray Interactions, Tokyo, July
1994 | null | null | null | hep-ph | null | Recent results in QCD on multiplicity distributions are briefly reviewed. QCD
is able to predict very tiny features of multiplicity distributions which
demonstrate that the negative binomial distribution (and, more generally, any
infinitely divisible distribution) is inappropriate for precise description of
experimental data. New fits of high energy multiplicity distributions can be
derived.
| [
{
"created": "Thu, 18 Aug 1994 03:43:45 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dremin",
"I. M.",
""
]
] | Recent results in QCD on multiplicity distributions are briefly reviewed. QCD is able to predict very tiny features of multiplicity distributions which demonstrate that the negative binomial distribution (and, more generally, any infinitely divisible distribution) is inappropriate for precise description of experimental data. New fits of high energy multiplicity distributions can be derived. |
1002.1589 | Rasna Rajkhowa | R.Rajkhowa, U. Jamil and J.K. Sarma | Polarized Dokshitzer-Gribov-Lipatov- Altarelli-Parisi equations and
t-evolution of structure functions in next-to-leading order at small-x | 19 pages, 3 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper the spin-dependent singlet and non-singlet structure functions
have been obtained by solving Dokshitzer-Gribov-Lipatov-Altarelli-Parisi
evolution equations in next-to-leading order in the small x limit. Here we have
used Taylor series expansion and then the particular and unique solution to
solve the evolution equations. We have also calculated t evolutions of
deuteron, proton and neutron structure functions and the results are compared
with the SLAC E-143 Collaboration data.
| [
{
"created": "Mon, 8 Feb 2010 12:30:43 GMT",
"version": "v1"
}
] | 2010-02-09 | [
[
"Rajkhowa",
"R.",
""
],
[
"Jamil",
"U.",
""
],
[
"Sarma",
"J. K.",
""
]
] | In this paper the spin-dependent singlet and non-singlet structure functions have been obtained by solving Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations in next-to-leading order in the small x limit. Here we have used Taylor series expansion and then the particular and unique solution to solve the evolution equations. We have also calculated t evolutions of deuteron, proton and neutron structure functions and the results are compared with the SLAC E-143 Collaboration data. |
1003.4533 | Daniel de Florian | Daniel de Florian and Werner Vogelsang | Helicity Parton Distributions from Spin Asymmetries in W-Boson
Production at RHIC | 22 pages, 13 figures included. Typos in Figs 2, 6, 8 and scales
corrected | Phys.Rev.D81:094020,2010 | 10.1103/PhysRevD.81.094020 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a next-to-leading order QCD calculation of the cross section and
longitudinal spin asymmetry in single-inclusive charged-lepton production, pp
-> l X, at RHIC, where the lepton is produced in the decay of an electroweak
gauge boson. Our calculation is presented in terms of a multi-purpose
Monte-Carlo integration program that may be readily used to include
experimental spin asymmetry data in a global analysis of helicity parton
densities. We perform a toy global analysis, studying the impact of anticipated
RHIC data on our knowledge about the polarized anti-quark distributions.
| [
{
"created": "Tue, 23 Mar 2010 21:18:25 GMT",
"version": "v1"
},
{
"created": "Sun, 9 May 2010 17:52:50 GMT",
"version": "v2"
},
{
"created": "Tue, 8 Mar 2011 02:34:27 GMT",
"version": "v3"
}
] | 2011-03-09 | [
[
"de Florian",
"Daniel",
""
],
[
"Vogelsang",
"Werner",
""
]
] | We present a next-to-leading order QCD calculation of the cross section and longitudinal spin asymmetry in single-inclusive charged-lepton production, pp -> l X, at RHIC, where the lepton is produced in the decay of an electroweak gauge boson. Our calculation is presented in terms of a multi-purpose Monte-Carlo integration program that may be readily used to include experimental spin asymmetry data in a global analysis of helicity parton densities. We perform a toy global analysis, studying the impact of anticipated RHIC data on our knowledge about the polarized anti-quark distributions. |
0706.3944 | Kunihiko Terasaki | Kunihiko Terasaki | A new tetra-quark interpretation of X(3872) | 4 pages, 0 figures, RevTeX, description clarified | Prog. Theor. Phys. 118: 821-826, 2007 | 10.1143/PTP.118.821 | YITP-07-36, KANAZAWA-0707 | hep-ph hep-ex nucl-th | null | A new tetra-quark interpretation of X(3872) is presented. In this model,
X(3872) consists of two degenerate tetra-quark mesons, {[cn](cbar nbar) +-
(cn)[cbar nbar]}_{I=0}, and, therefore, it is naturally understood that X(3872)
decays into two different eigenstates of G-parity.
| [
{
"created": "Wed, 27 Jun 2007 02:01:38 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Jul 2007 02:26:30 GMT",
"version": "v2"
},
{
"created": "Mon, 12 Nov 2007 01:08:20 GMT",
"version": "v3"
}
] | 2015-05-13 | [
[
"Terasaki",
"Kunihiko",
""
]
] | A new tetra-quark interpretation of X(3872) is presented. In this model, X(3872) consists of two degenerate tetra-quark mesons, {[cn](cbar nbar) +- (cn)[cbar nbar]}_{I=0}, and, therefore, it is naturally understood that X(3872) decays into two different eigenstates of G-parity. |
1312.5329 | David M. Straub | Adam Falkowski, David M. Straub, and Avelino Vicente | Vector-like leptons: Higgs decays and collider phenomenology | 16 pages, 5 figures | null | 10.1007/JHEP05(2014)092 | LPT-Orsay-13-141 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the impact of heavy vector-like leptons on several observables in
collider and low-energy physics. These states, present in many well-motivated
extensions of the Standard Model, can induce lepton flavour violation and
non-standard Higgs decays. We study these effects in an effective model
inspired by the composite Higgs scenario. After deriving bounds on the mass and
production cross-section of the vector-like states using recent LHC data on
multilepton searches, we discuss the modification of the Higgs decays to
dilepton, diphoton and $Z\gamma$ final states as well as low-energy observables
like radiative lepton decays, the anomalous magnetic moment of the muon and the
electric dipole moment of the electron. We find several interesting
correlations. In particular, we show that branching fractions of lepton
flavour-violating Higgs decays at an observable level are prohibited due to the
strong bounds on the radiative lepton decays.
| [
{
"created": "Wed, 18 Dec 2013 21:00:13 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Falkowski",
"Adam",
""
],
[
"Straub",
"David M.",
""
],
[
"Vicente",
"Avelino",
""
]
] | We study the impact of heavy vector-like leptons on several observables in collider and low-energy physics. These states, present in many well-motivated extensions of the Standard Model, can induce lepton flavour violation and non-standard Higgs decays. We study these effects in an effective model inspired by the composite Higgs scenario. After deriving bounds on the mass and production cross-section of the vector-like states using recent LHC data on multilepton searches, we discuss the modification of the Higgs decays to dilepton, diphoton and $Z\gamma$ final states as well as low-energy observables like radiative lepton decays, the anomalous magnetic moment of the muon and the electric dipole moment of the electron. We find several interesting correlations. In particular, we show that branching fractions of lepton flavour-violating Higgs decays at an observable level are prohibited due to the strong bounds on the radiative lepton decays. |
1809.00425 | Yoshio Koide | Yoshio Koide | What Physics Does The Charged Lepton Mass Relation Tell Us? | 5 pge, Conference report | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The charged lepton mass relation $K \equiv (m_e +m_\mu+m_\tau)/(\sqrt{m_e}
%+\sqrt{m_\mu} +\sqrt{m_\tau})^2= 2/3 $
is excellently satisfied by observed masses (pole masses). However, the
formula $K=2/3$ should be never satisfied with the observed charged lepton
masses. We will review a mechanism by proposed by Sumino and recent related
topics.
| [
{
"created": "Mon, 3 Sep 2018 02:06:38 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Nov 2019 08:33:52 GMT",
"version": "v2"
},
{
"created": "Tue, 12 Nov 2019 11:06:56 GMT",
"version": "v3"
}
] | 2019-11-13 | [
[
"Koide",
"Yoshio",
""
]
] | The charged lepton mass relation $K \equiv (m_e +m_\mu+m_\tau)/(\sqrt{m_e} %+\sqrt{m_\mu} +\sqrt{m_\tau})^2= 2/3 $ is excellently satisfied by observed masses (pole masses). However, the formula $K=2/3$ should be never satisfied with the observed charged lepton masses. We will review a mechanism by proposed by Sumino and recent related topics. |
1512.07889 | Shun Zhou | Jue Zhang and Shun Zhou | Electroweak Vacuum Stability and Diphoton Excess at 750 GeV | 17 pages, 2 figures, an error removed, numerical results revised,
more discussions added, to be published in Chin. Phys. C | Chin. Phys. C 40 (2016) 081001 | 10.1088/1674-1137/40/8/081001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently, both ATLAS and CMS collaborations at the CERN Large Hadron Collider
(LHC) have announced their observations of an excess of diphoton events around
the invariant mass of $750~{\rm GeV}$ with a local significance of $3.6\sigma$
and $2.6\sigma$, respectively. In this paper, we interpret the diphoton excess
as the on-shell production of a real singlet scalar in the $pp \to S \to \gamma
\gamma$ channel. To accommodate the observed production rate, we further
introduce a vector-like fermion $F$, which is carrying both color and electric
charges. The viable regions of model parameters are explored for this simple
extension of the Standard Model (SM). Moreover, we revisit the problem of
electroweak vacuum stability in the same scenario, and find that the
requirement for the electroweak vacuum stability up to high energy scales
imposes serious constraints on the Yukawa coupling of the vector-like fermion
and the quartic couplings of the SM Higgs boson and the new singlet scalar.
Consequently, a successful explanation for the diphoton excess and the absolute
stability of electroweak vacuum cannot be achieved simultaneously in this
economical setup.
| [
{
"created": "Thu, 24 Dec 2015 19:21:57 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Dec 2015 17:24:26 GMT",
"version": "v2"
},
{
"created": "Thu, 28 Apr 2016 08:30:07 GMT",
"version": "v3"
}
] | 2016-05-04 | [
[
"Zhang",
"Jue",
""
],
[
"Zhou",
"Shun",
""
]
] | Recently, both ATLAS and CMS collaborations at the CERN Large Hadron Collider (LHC) have announced their observations of an excess of diphoton events around the invariant mass of $750~{\rm GeV}$ with a local significance of $3.6\sigma$ and $2.6\sigma$, respectively. In this paper, we interpret the diphoton excess as the on-shell production of a real singlet scalar in the $pp \to S \to \gamma \gamma$ channel. To accommodate the observed production rate, we further introduce a vector-like fermion $F$, which is carrying both color and electric charges. The viable regions of model parameters are explored for this simple extension of the Standard Model (SM). Moreover, we revisit the problem of electroweak vacuum stability in the same scenario, and find that the requirement for the electroweak vacuum stability up to high energy scales imposes serious constraints on the Yukawa coupling of the vector-like fermion and the quartic couplings of the SM Higgs boson and the new singlet scalar. Consequently, a successful explanation for the diphoton excess and the absolute stability of electroweak vacuum cannot be achieved simultaneously in this economical setup. |
hep-ph/0601191 | Jaume Guasch | Santi Bejar, Jaume Guasch, Joan Sola | SUSY Higgs boson flavor-changing neutral currents at the LHC | 6 pages, LaTeX, 3 figures, 3 tables, to appear in the proceedings of
the "7th International Symposium on Radiative Corrections (RADCOR05)", Shonan
Village, Japan, 2005. References updated | null | 10.1016/j.nuclphysbps.2006.03.042 | UAB-FT-597, UB-ECM-PF-06/03 | hep-ph | null | We compute and analyze the Flavor-Changing Neutral Current (FCNC)
interactions of Minimal Supersymmetric Standard Model Higgs bosons (h = h0, H0,
A0) with heavy quarks (top and bottom), focusing on the strongly-interacting
sector. We correlate the Higgs bosons production cross-section at the LHC with
the FCNC decay branching ratios and find the maximum allowed values of the
production rates, sigma(pp -> h -> qq') = sigma(pp -> h) x B(h -> qq') (qq'= tc
or bs) after taking into account limits from low energy data on flavor-changing
interactions. We single out the top channel, with a maximum production rate of
sigma^max(pp -> h -> tc) =~ 10^-3 - 10^-2 pb, as the most promising FCNC
channel to be detected at the LHC.
| [
{
"created": "Mon, 23 Jan 2006 18:55:33 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Jan 2006 15:39:14 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Bejar",
"Santi",
""
],
[
"Guasch",
"Jaume",
""
],
[
"Sola",
"Joan",
""
]
] | We compute and analyze the Flavor-Changing Neutral Current (FCNC) interactions of Minimal Supersymmetric Standard Model Higgs bosons (h = h0, H0, A0) with heavy quarks (top and bottom), focusing on the strongly-interacting sector. We correlate the Higgs bosons production cross-section at the LHC with the FCNC decay branching ratios and find the maximum allowed values of the production rates, sigma(pp -> h -> qq') = sigma(pp -> h) x B(h -> qq') (qq'= tc or bs) after taking into account limits from low energy data on flavor-changing interactions. We single out the top channel, with a maximum production rate of sigma^max(pp -> h -> tc) =~ 10^-3 - 10^-2 pb, as the most promising FCNC channel to be detected at the LHC. |
hep-ph/9906268 | Jaume Guasch | Jaume Guasch, Joan Sola | FCNC top quark decay in the MSSM: a door to SUSY physics in high
luminosity colliders? | 22 pages, LaTeX2e, 10 figs. included. Title changed. Note and
references added | Nucl.Phys.B562:3-28,1999 | 10.1016/S0550-3213(99)00579-9 | UAB-FT-429, KA-TP-6-99 | hep-ph | null | We study the FCNC top quark decays t -> c h in the framework of the MSSM,
where h= h^0,H^0,A^0 is any of the supersymmetric neutral Higgs bosons. We
include the leading set of SUSY-QCD and SUSY electroweak contributions. While
the FCNC top quark decay into the SM Higgs boson has such a negligible rate
that will not be accessible to any presently conceivable accelerator, we find
that there is a chance that the potential rates in the MSSM can be measured at
the high luminosity colliders round the corner, especially at the LHC and
possibly at a future LC, but we deem it difficult at the upgraded Tevatron. In
view of the large SUSY-QCD effects that we find in the Higgs channels, and due
to some discrepancies in the literature, we have revisited the FCNC top quark
decay into gluon, t -> c g, in our framework. We confirm that the possibility
of sizeable rates does not necessarily require a general pattern of
gluino-mediated FCNC interactions affecting both the LH and the RH sfermion
sectors -- the LH one being sufficient. However, given the present bounds on
sparticle masses, the gluon channel turns out to lie just below the expected
experimental sensibility, so our general conclusion is that the Higgs channels
t -> c h (especially the one for the light CP-even Higgs) have the largest
potential top quark FCNC rates in the MSSM, namely of order 10^-4.
| [
{
"created": "Mon, 7 Jun 1999 18:29:27 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Jun 1999 11:20:24 GMT",
"version": "v2"
}
] | 2011-02-11 | [
[
"Guasch",
"Jaume",
""
],
[
"Sola",
"Joan",
""
]
] | We study the FCNC top quark decays t -> c h in the framework of the MSSM, where h= h^0,H^0,A^0 is any of the supersymmetric neutral Higgs bosons. We include the leading set of SUSY-QCD and SUSY electroweak contributions. While the FCNC top quark decay into the SM Higgs boson has such a negligible rate that will not be accessible to any presently conceivable accelerator, we find that there is a chance that the potential rates in the MSSM can be measured at the high luminosity colliders round the corner, especially at the LHC and possibly at a future LC, but we deem it difficult at the upgraded Tevatron. In view of the large SUSY-QCD effects that we find in the Higgs channels, and due to some discrepancies in the literature, we have revisited the FCNC top quark decay into gluon, t -> c g, in our framework. We confirm that the possibility of sizeable rates does not necessarily require a general pattern of gluino-mediated FCNC interactions affecting both the LH and the RH sfermion sectors -- the LH one being sufficient. However, given the present bounds on sparticle masses, the gluon channel turns out to lie just below the expected experimental sensibility, so our general conclusion is that the Higgs channels t -> c h (especially the one for the light CP-even Higgs) have the largest potential top quark FCNC rates in the MSSM, namely of order 10^-4. |
hep-ph/9808434 | A. Bialas | A.Bialas | Quark model and strange baryon production in heavy ion collisions | latex, 7 pages | Phys.Lett. B442 (1998) 449-452 | 10.1016/S0370-2693(98)01250-7 | TPJU - 21/98 | hep-ph | null | It is pointed out that the recent data on strange baryon and antibaryon
production in Pb-Pb collisions at 159 GeV/c agree well with the hypothesis of
an intermediate state of quasi-free and randomly distributed constituent quarks
and antiquarks. Also the S-S data are consistent with this hypothesis. The p-Pb
data follow a different pattern.
| [
{
"created": "Thu, 27 Aug 1998 09:29:01 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Bialas",
"A.",
""
]
] | It is pointed out that the recent data on strange baryon and antibaryon production in Pb-Pb collisions at 159 GeV/c agree well with the hypothesis of an intermediate state of quasi-free and randomly distributed constituent quarks and antiquarks. Also the S-S data are consistent with this hypothesis. The p-Pb data follow a different pattern. |
1305.5364 | Anna Kaminska | Anna Kaminska | Composite or elementary? Probing the nature of the Higgs | Talk given at Rencontres de Moriond QCD, 2013 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I discuss consequences of electroweak symmetry breaking by strong dynamics,
assuming the existence of a light composite scalar appearing as a
pseudo-Goldstone boson of some global symmetry of the new strongly interacting
sector. In such a scenario, the composite scalar has properties very similar to
the Standard Model Higgs, but the existence of additional resonances with
different spins is also expected. Properties and phenomenology of lightest
spin-1 resonances are considered in a simple general effective Lagrangian
description. The question whether the effects of spin-1 resonances can be
observed at the LHC, shedding light on the nature of the Higgs boson, is
addressed.
| [
{
"created": "Thu, 23 May 2013 09:55:27 GMT",
"version": "v1"
}
] | 2013-05-24 | [
[
"Kaminska",
"Anna",
""
]
] | I discuss consequences of electroweak symmetry breaking by strong dynamics, assuming the existence of a light composite scalar appearing as a pseudo-Goldstone boson of some global symmetry of the new strongly interacting sector. In such a scenario, the composite scalar has properties very similar to the Standard Model Higgs, but the existence of additional resonances with different spins is also expected. Properties and phenomenology of lightest spin-1 resonances are considered in a simple general effective Lagrangian description. The question whether the effects of spin-1 resonances can be observed at the LHC, shedding light on the nature of the Higgs boson, is addressed. |
2104.14182 | Denny Lane Sombillo | Denny Lane B. Sombillo and Yoichi Ikeda and Toru Sato and Atsushi
Hosaka | Unveiling the pole structure of S-matrix using deep learning | 7 pages, 3 figures, 2 tables, Added references | null | null | null | hep-ph hep-ex nucl-ex nucl-th quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Particle scattering is a powerful tool to unveil the nature of various
subatomic phenomena. The key quantity is the scattering amplitude whose
analytic structure carries the information of the quantum states. In this work,
we demonstrate our first step attempt to extract the pole configuration of
inelastic scatterings using the deep learning method. Among various problems,
motivated by the recent new hadron phenomena, we develop a curriculum learning
method of deep neural network to analyze coupled channel scattering problems.
We show how effectively the method works to extract the pole configuration
associated with resonances in the $\pi N$ scatterings.
| [
{
"created": "Thu, 29 Apr 2021 08:00:34 GMT",
"version": "v1"
},
{
"created": "Wed, 12 May 2021 02:19:53 GMT",
"version": "v2"
}
] | 2021-05-13 | [
[
"Sombillo",
"Denny Lane B.",
""
],
[
"Ikeda",
"Yoichi",
""
],
[
"Sato",
"Toru",
""
],
[
"Hosaka",
"Atsushi",
""
]
] | Particle scattering is a powerful tool to unveil the nature of various subatomic phenomena. The key quantity is the scattering amplitude whose analytic structure carries the information of the quantum states. In this work, we demonstrate our first step attempt to extract the pole configuration of inelastic scatterings using the deep learning method. Among various problems, motivated by the recent new hadron phenomena, we develop a curriculum learning method of deep neural network to analyze coupled channel scattering problems. We show how effectively the method works to extract the pole configuration associated with resonances in the $\pi N$ scatterings. |
2202.12317 | Ana Luisa Foguel | Enrico Bertuzzo, Ana Luisa Foguel, Gabriel M. Salla and Renata
Zukanovich Funchal | New Limits on Leptophilic Axionlike Particles and Majorons from ArgoNeuT | 8 pages, 4 figures; v2: extended discussion of the analysis and new
appendices; matches version published at PRL | null | 10.1103/PhysRevLett.130.171801 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Axionlike particles are among the most studied extensions of the standard
model. In this Letter we study the bounds that the ArgoNeuT experiment can put
on the parameter space of two specific scenarios: leptophilic axionlike
particles and Majorons. We find that such bounds are currently the most
constraining ones in the (0.2 - 1.7) GeV mass range.
| [
{
"created": "Thu, 24 Feb 2022 19:03:36 GMT",
"version": "v1"
},
{
"created": "Mon, 1 May 2023 20:31:20 GMT",
"version": "v2"
}
] | 2023-05-03 | [
[
"Bertuzzo",
"Enrico",
""
],
[
"Foguel",
"Ana Luisa",
""
],
[
"Salla",
"Gabriel M.",
""
],
[
"Funchal",
"Renata Zukanovich",
""
]
] | Axionlike particles are among the most studied extensions of the standard model. In this Letter we study the bounds that the ArgoNeuT experiment can put on the parameter space of two specific scenarios: leptophilic axionlike particles and Majorons. We find that such bounds are currently the most constraining ones in the (0.2 - 1.7) GeV mass range. |
hep-ph/9711345 | Jean Letessier | Jean Letessier, Jan Rafelski, Ahmed Tounsi | Strange Particle Abundance in QGP Formed in 200 GeV A Nuclear Collisions | 11 pages, LaTeX, 3 postscript figures, Phys. Lett. B 323 (1994) 393 | Phys.Lett. B323 (1994) 393-400 | 10.1016/0370-2693(94)91237-8 | null | hep-ph nucl-th | null | We investigate here the relative abundance of strange particles produced in
nuclear collisions at the SPS energies (9 GeV A in CM frame) assuming that the
central reaction fireball consists of quark-gluon plasma. We show that the
total strangeness yield in S-S, S-Ag and S-W reactions is compatible with this
picture.
| [
{
"created": "Mon, 17 Nov 1997 11:31:02 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Letessier",
"Jean",
""
],
[
"Rafelski",
"Jan",
""
],
[
"Tounsi",
"Ahmed",
""
]
] | We investigate here the relative abundance of strange particles produced in nuclear collisions at the SPS energies (9 GeV A in CM frame) assuming that the central reaction fireball consists of quark-gluon plasma. We show that the total strangeness yield in S-S, S-Ag and S-W reactions is compatible with this picture. |
hep-ph/9408308 | null | Nick Evans | Additional Fermion Families and Precision Electroweak Data | 7 pages + 4 appended ps diags, SWAT-40 | Phys.Lett. B340 (1994) 81-85 | 10.1016/0370-2693(94)91301-3 | null | hep-ph | null | The S,T, and U formalism for studying electroweak precision data has recently
been updated to include the effects of new light physics and within this
analysis the latest LEP and SLC data tightly constrain models of physics beyond
the Standard Model. We re-examine the constraints on additional strong and
weakly interacting fermion families in the light of these developments. We
conclude that the precision data favour models with at least one fermion with a
mass below 150GeV.
| [
{
"created": "Wed, 17 Aug 1994 12:06:25 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Evans",
"Nick",
""
]
] | The S,T, and U formalism for studying electroweak precision data has recently been updated to include the effects of new light physics and within this analysis the latest LEP and SLC data tightly constrain models of physics beyond the Standard Model. We re-examine the constraints on additional strong and weakly interacting fermion families in the light of these developments. We conclude that the precision data favour models with at least one fermion with a mass below 150GeV. |
0712.4270 | A. J. Buchmann | A.J. Buchmann | Charge form factors and nucleon shape | 14 pages, 5 figures, Proceedings of Shapes of Hadrons Workshop,
Athens, Greece, 27-29 April 2006 | AIP Conf.Proc.904:110-125,2007 | 10.1063/1.2734297 | null | hep-ph nucl-th | null | To obtain further information on the geometric shape of the nucleon, the
proton charge form factor is decomposed into two terms, which are connected
respectively with a spherically symmetric and an intrinsic quadrupole part of
the proton's charge density. Quark model relations are employed to derive
expressions for both terms. In particular, the proton's intrinsic quadrupole
form factor is obtained from a relation between the N -> Delta and neutron
charge form factors. The proposed decomposition shows that the neutron charge
form factor is an observable manifestation of an intrinsic quadrupole form
factor of the nucleon. Furthermore, it affords an interpretation of recent
electron-nucleon scattering data in terms of a nonspherical distribution of
quark-antiquark pairs in the nucleon.
| [
{
"created": "Thu, 27 Dec 2007 19:56:34 GMT",
"version": "v1"
}
] | 2010-11-11 | [
[
"Buchmann",
"A. J.",
""
]
] | To obtain further information on the geometric shape of the nucleon, the proton charge form factor is decomposed into two terms, which are connected respectively with a spherically symmetric and an intrinsic quadrupole part of the proton's charge density. Quark model relations are employed to derive expressions for both terms. In particular, the proton's intrinsic quadrupole form factor is obtained from a relation between the N -> Delta and neutron charge form factors. The proposed decomposition shows that the neutron charge form factor is an observable manifestation of an intrinsic quadrupole form factor of the nucleon. Furthermore, it affords an interpretation of recent electron-nucleon scattering data in terms of a nonspherical distribution of quark-antiquark pairs in the nucleon. |
2012.05763 | Johannes Rosskopp | Stefan Antusch and Johannes Rosskopp | Heavy Neutrino-Antineutrino Oscillations in Quantum Field Theory | 24 pages plus appendix, 3 figures, matches journal version | null | 10.1007/JHEP03(2021)170 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | It has been proposed that the coherent propagation of long-lived heavy
neutrino mass eigenstates can lead to an oscillating rate of lepton number
conserving (LNC) and violating (LNV) events, as a function of the distance
between the production and displaced decay vertices. We discuss this
phenomenon, which we refer to as heavy neutrino-antineutrino oscillations, in
the framework of quantum field theory (QFT), using the formalism of external
wave packets. General formulae for the oscillation probabilities and the number
of expected events are derived and the coherence and localisation conditions
that have to be satisfied in order for neutrino-antineutrino oscillations to be
observable are discussed. The formulae are then applied to a low scale seesaw
scenario, which features two nearly mass degenerate heavy neutrinos that can be
sufficiently long lived to produce a displaced vertex when their masses are
below the $W$ boson mass. The leading and next-to-leading order oscillation
formulae for this scenario are derived. For an example parameter point used in
previous studies, the kinematics of the considered LNC/LNV processes are
simulated, to check that the coherence and localisation conditions are
satisfied. Our results show that the phenomenon of heavy neutrino-antineutrino
oscillations can indeed occur in low scale seesaw scenarios and that the
previously used leading order formulae, derived with a plane wave approach,
provide a good approximation for the considered example parameter point.
| [
{
"created": "Thu, 10 Dec 2020 15:47:56 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Dec 2020 13:08:38 GMT",
"version": "v2"
},
{
"created": "Wed, 31 Mar 2021 13:03:39 GMT",
"version": "v3"
}
] | 2021-04-01 | [
[
"Antusch",
"Stefan",
""
],
[
"Rosskopp",
"Johannes",
""
]
] | It has been proposed that the coherent propagation of long-lived heavy neutrino mass eigenstates can lead to an oscillating rate of lepton number conserving (LNC) and violating (LNV) events, as a function of the distance between the production and displaced decay vertices. We discuss this phenomenon, which we refer to as heavy neutrino-antineutrino oscillations, in the framework of quantum field theory (QFT), using the formalism of external wave packets. General formulae for the oscillation probabilities and the number of expected events are derived and the coherence and localisation conditions that have to be satisfied in order for neutrino-antineutrino oscillations to be observable are discussed. The formulae are then applied to a low scale seesaw scenario, which features two nearly mass degenerate heavy neutrinos that can be sufficiently long lived to produce a displaced vertex when their masses are below the $W$ boson mass. The leading and next-to-leading order oscillation formulae for this scenario are derived. For an example parameter point used in previous studies, the kinematics of the considered LNC/LNV processes are simulated, to check that the coherence and localisation conditions are satisfied. Our results show that the phenomenon of heavy neutrino-antineutrino oscillations can indeed occur in low scale seesaw scenarios and that the previously used leading order formulae, derived with a plane wave approach, provide a good approximation for the considered example parameter point. |
1712.07469 | En Wang | Li-Juan liu, En Wang, Ju-Jun Xie, Kai-Lan Song, Jing-Yu Zhu | $\Lambda(1405)$ production in the process $\chi_{c0}(1P)\to
\bar{\Lambda}\Sigma\pi$ | 7 pages, 13 figures, the version for PRD | Phys. Rev. D 98, 114017 (2018) | 10.1103/PhysRevD.98.114017 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have performed a theoretical study on the process $\chi_{c0}(1P)\to
\bar{\Lambda}\Sigma\pi$, by taking into account the final state interactions of
$\pi\Sigma$ and $\pi\bar{\Lambda}$ based on the chiral unitary approach. As the
isospin filters of $I=0$ in the $\pi\Sigma$ channel and $I=1$ in the
$\pi\bar{\Lambda}$ channel, this process can be used to study the molecular
structure of the $\Lambda(1405)$ resonance, and to test the existence of the
predicted states $\Sigma(1380)$ and $\Sigma(1430)$ with spin-parity
$J^P=1/2^-$. Our results show that there is a peak around $1350 \sim 1400$~MeV,
and a cusp around the $\bar{K}N$ threshold in the $\pi\Sigma$ invariant mass
distribution, which should be the important feature of the molecular state
$\Lambda(1405)$. We also find a peak around $1380$~MeV, and a cusp around
$\bar{K}N$ threshold in the $\pi\bar{\Lambda}$ invariant mass distribution,
which are associated to the $\Sigma(1380)$ and $\Sigma(1430)$ resonances.
| [
{
"created": "Wed, 20 Dec 2017 13:25:43 GMT",
"version": "v1"
},
{
"created": "Sun, 17 Jun 2018 03:14:43 GMT",
"version": "v2"
},
{
"created": "Thu, 13 Dec 2018 02:00:02 GMT",
"version": "v3"
}
] | 2018-12-26 | [
[
"liu",
"Li-Juan",
""
],
[
"Wang",
"En",
""
],
[
"Xie",
"Ju-Jun",
""
],
[
"Song",
"Kai-Lan",
""
],
[
"Zhu",
"Jing-Yu",
""
]
] | We have performed a theoretical study on the process $\chi_{c0}(1P)\to \bar{\Lambda}\Sigma\pi$, by taking into account the final state interactions of $\pi\Sigma$ and $\pi\bar{\Lambda}$ based on the chiral unitary approach. As the isospin filters of $I=0$ in the $\pi\Sigma$ channel and $I=1$ in the $\pi\bar{\Lambda}$ channel, this process can be used to study the molecular structure of the $\Lambda(1405)$ resonance, and to test the existence of the predicted states $\Sigma(1380)$ and $\Sigma(1430)$ with spin-parity $J^P=1/2^-$. Our results show that there is a peak around $1350 \sim 1400$~MeV, and a cusp around the $\bar{K}N$ threshold in the $\pi\Sigma$ invariant mass distribution, which should be the important feature of the molecular state $\Lambda(1405)$. We also find a peak around $1380$~MeV, and a cusp around $\bar{K}N$ threshold in the $\pi\bar{\Lambda}$ invariant mass distribution, which are associated to the $\Sigma(1380)$ and $\Sigma(1430)$ resonances. |
2207.13258 | Hongxi Xing | Tianyin Li, Xingyu Guo, Wai Kin Lai, Xiaohui Liu, Enke Wang, Hongxi
Xing, Dan-Bo Zhang, Shi-Liang Zhu | Exploring Light-Cone Distribution Amplitudes from Quantum Computing | 8 pages, 7 figures, published version in Sci.China Phys.Mech.Astron | null | 10.1007/s11433-023-2120-1 | null | hep-ph hep-ex nucl-th quant-ph | http://creativecommons.org/licenses/by/4.0/ | Light-cone distribution amplitudes (LCDAs) are essential nonperturbative
quantities for theoretical predictions of exclusive high-energy processes in
quantum chromodynamics (QCD). We demonstrate the prospect of calculating LCDAs
on a quantum computer by applying a recently proposed quantum algorithm, with
staggered fermions, to the simulation of the LCDA in the (1+1)-dimensional
Nambu-Jona-Lasinio (NJL) model on classical hardware. The agreement between the
result from the classical simulation of the quantum algorithm and that from
exact diagonalization justifies the proposed quantum algorithm. We find that
the resulting LCDA in the NJL model exhibits features shared with the LCDAs
obtained from QCD.
| [
{
"created": "Wed, 27 Jul 2022 02:45:47 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Oct 2023 02:12:18 GMT",
"version": "v2"
}
] | 2023-10-19 | [
[
"Li",
"Tianyin",
""
],
[
"Guo",
"Xingyu",
""
],
[
"Lai",
"Wai Kin",
""
],
[
"Liu",
"Xiaohui",
""
],
[
"Wang",
"Enke",
""
],
[
"Xing",
"Hongxi",
""
],
[
"Zhang",
"Dan-Bo",
""
],
[
"Zhu",
"Shi-Lia... | Light-cone distribution amplitudes (LCDAs) are essential nonperturbative quantities for theoretical predictions of exclusive high-energy processes in quantum chromodynamics (QCD). We demonstrate the prospect of calculating LCDAs on a quantum computer by applying a recently proposed quantum algorithm, with staggered fermions, to the simulation of the LCDA in the (1+1)-dimensional Nambu-Jona-Lasinio (NJL) model on classical hardware. The agreement between the result from the classical simulation of the quantum algorithm and that from exact diagonalization justifies the proposed quantum algorithm. We find that the resulting LCDA in the NJL model exhibits features shared with the LCDAs obtained from QCD. |
1312.2955 | Fady Bishara | Fady Bishara, Yuval Grossman, Roni Harnik, Dean J. Robinson, Jing Shu
and Jure Zupan | Probing CP Violation in $h\rightarrow\gamma\gamma$ with Converted
Photons | 49 pages, 15 figures; updated to match JHEP and fixed minor typos | null | 10.1007/JHEP04(2014)084 | FERMILAB-PUB-13-540-T | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study Higgs diphoton decays, in which both photons undergo nuclear
conversion to electron- positron pairs. The kinematic distribution of the two
electron-positron pairs may be used to probe the CP violating (CPV) coupling of
the Higgs to photons, that may be produced by new physics. Detecting CPV in
this manner requires interference between the spin-polarized helicity
amplitudes for both conversions. We derive leading order, analytic forms for
these amplitudes. In turn, we obtain compact, leading-order expressions for the
full process rate. While performing experiments involving photon conversions
may be challenging, we use the results of our analysis to construct
experimental cuts on certain observables that may enhance sensitivity to CPV.
We show that there exist regions of phase space on which sensitivity to CPV is
of order unity. The statistical sensitivity of these cuts are verified
numerically, using dedicated Monte-Carlo simulations.
| [
{
"created": "Tue, 10 Dec 2013 21:00:05 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Nov 2015 21:00:55 GMT",
"version": "v2"
}
] | 2015-11-11 | [
[
"Bishara",
"Fady",
""
],
[
"Grossman",
"Yuval",
""
],
[
"Harnik",
"Roni",
""
],
[
"Robinson",
"Dean J.",
""
],
[
"Shu",
"Jing",
""
],
[
"Zupan",
"Jure",
""
]
] | We study Higgs diphoton decays, in which both photons undergo nuclear conversion to electron- positron pairs. The kinematic distribution of the two electron-positron pairs may be used to probe the CP violating (CPV) coupling of the Higgs to photons, that may be produced by new physics. Detecting CPV in this manner requires interference between the spin-polarized helicity amplitudes for both conversions. We derive leading order, analytic forms for these amplitudes. In turn, we obtain compact, leading-order expressions for the full process rate. While performing experiments involving photon conversions may be challenging, we use the results of our analysis to construct experimental cuts on certain observables that may enhance sensitivity to CPV. We show that there exist regions of phase space on which sensitivity to CPV is of order unity. The statistical sensitivity of these cuts are verified numerically, using dedicated Monte-Carlo simulations. |
1409.7000 | Chengcheng Han | Chengcheng Han | Probing light bino and higgsinos at the LHC | 15 pages, 5 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the naturalness, we study a simplified MSSM scenario where only
the bino-like LSP and higgsino-like NLSP are light. We first scan the parameter
space of this scenario, considering the constraints from the Higgs mass, flavor
physics, electroweak precision measurements and dark matter experiments. Then
in the allowed parameter space, we perform a Monte Carlo simulation for the
$\tilde{\chi}^\pm_1 \tilde{\chi}^0_{2,3}$ production followed by
$\tilde{\chi}^\pm_1 \to W^\pm \tilde{\chi}^0_1$ and $\tilde{\chi}^0_{2,3} \to
Z\tilde{\chi}^0_1$. By examining the presently available trilepton bounds on
the wino-like chargino/neutralino, we find that only a narrow region
$40\,\rm{GeV} \lesssim m_{\tilde{\chi}^0_1} \lesssim 50\,\rm{GeV}$ and
$160\,\rm{GeV} \lesssim m_{\tilde{\chi}^0_{2,3}} \lesssim 170\,\rm {GeV}$ on
the plane of $m_{\tilde{\chi}^0_1}-m_{\tilde{\chi}^0_{2,3}}$ can be excluded.
Finally, we explore the potential of trilepton signature in probing such a
scenario at 14 TeV LHC and find that the region with $40\,\rm{GeV} \lesssim
m_{\tilde{\chi}^0_1} \lesssim 60\,\rm {GeV}$ and $160 \rm {GeV}\,\lesssim
m_{\tilde{\chi}^0_{2,3}} \lesssim 300\,\rm{GeV}$ can be covered at $3\sigma$
level with luminosity ${\cal L}=300$ fb$^{-1}$.
| [
{
"created": "Wed, 24 Sep 2014 15:46:17 GMT",
"version": "v1"
},
{
"created": "Sun, 7 Dec 2014 12:25:54 GMT",
"version": "v2"
}
] | 2014-12-09 | [
[
"Han",
"Chengcheng",
""
]
] | Motivated by the naturalness, we study a simplified MSSM scenario where only the bino-like LSP and higgsino-like NLSP are light. We first scan the parameter space of this scenario, considering the constraints from the Higgs mass, flavor physics, electroweak precision measurements and dark matter experiments. Then in the allowed parameter space, we perform a Monte Carlo simulation for the $\tilde{\chi}^\pm_1 \tilde{\chi}^0_{2,3}$ production followed by $\tilde{\chi}^\pm_1 \to W^\pm \tilde{\chi}^0_1$ and $\tilde{\chi}^0_{2,3} \to Z\tilde{\chi}^0_1$. By examining the presently available trilepton bounds on the wino-like chargino/neutralino, we find that only a narrow region $40\,\rm{GeV} \lesssim m_{\tilde{\chi}^0_1} \lesssim 50\,\rm{GeV}$ and $160\,\rm{GeV} \lesssim m_{\tilde{\chi}^0_{2,3}} \lesssim 170\,\rm {GeV}$ on the plane of $m_{\tilde{\chi}^0_1}-m_{\tilde{\chi}^0_{2,3}}$ can be excluded. Finally, we explore the potential of trilepton signature in probing such a scenario at 14 TeV LHC and find that the region with $40\,\rm{GeV} \lesssim m_{\tilde{\chi}^0_1} \lesssim 60\,\rm {GeV}$ and $160 \rm {GeV}\,\lesssim m_{\tilde{\chi}^0_{2,3}} \lesssim 300\,\rm{GeV}$ can be covered at $3\sigma$ level with luminosity ${\cal L}=300$ fb$^{-1}$. |
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