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/0408059 | Antoni Szczurek | A. Szczurek | Kwieci\'Nski-CCFM Unintegrated Parton Distributions - a Few Applications | an invited talk at the international workshop DIS2004, Strbske Pleso,
Slovakia, April 14-18, 6 pages, 5 figures | null | null | null | hep-ph | null | A few applications of recent unintegrated parton distributions from the
solution of the recent equations formulated by Jan Kwieci\'nski are shown.
| [
{
"created": "Wed, 4 Aug 2004 10:55:59 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Szczurek",
"A.",
""
]
] | A few applications of recent unintegrated parton distributions from the solution of the recent equations formulated by Jan Kwieci\'nski are shown. |
hep-ph/9901254 | D. Elazzar Kaplan | D. Elazzar Kaplan and Ann E. Nelson | Solar and Atmospheric Neutrino Oscillations from Bilinear R-Parity
Violation | 14 pages, 2 figures, latex, references added | JHEP 0001:033,2000 | null | UW/99-02 | hep-ph | null | We discuss general predictions for neutrino masses and mixing angles from R
parity violation in the Minimal Supersymmetric Standard Model. If the soft
supersymmetry breaking terms are flavor blind at short distance, then the
leptonic analogue of the CKM matrix depends on only two real parameters, which
are completely determined by fits to solar and atmospheric neutrino
oscillations. Either the small angle MSW, large angle MSW, or ``just-so''
solutions to the solar neutrino problem are allowed, although the large angle
MSW solution requires substantial fine-tuning. The latter two cases require
significant $\nu_\mu\to\nu_e$ oscillations of atmospheric neutrinos. We present
a model which could explain bilinear R parity violation as a consequence of
spontaneous symmetry violation by a dynamical supersymmetry breaking sector.
The decay length and branching ratios of the LSP are estimated.
| [
{
"created": "Fri, 8 Jan 1999 18:58:04 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Apr 1999 03:42:15 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Kaplan",
"D. Elazzar",
""
],
[
"Nelson",
"Ann E.",
""
]
] | We discuss general predictions for neutrino masses and mixing angles from R parity violation in the Minimal Supersymmetric Standard Model. If the soft supersymmetry breaking terms are flavor blind at short distance, then the leptonic analogue of the CKM matrix depends on only two real parameters, which are completely determined by fits to solar and atmospheric neutrino oscillations. Either the small angle MSW, large angle MSW, or ``just-so'' solutions to the solar neutrino problem are allowed, although the large angle MSW solution requires substantial fine-tuning. The latter two cases require significant $\nu_\mu\to\nu_e$ oscillations of atmospheric neutrinos. We present a model which could explain bilinear R parity violation as a consequence of spontaneous symmetry violation by a dynamical supersymmetry breaking sector. The decay length and branching ratios of the LSP are estimated. |
1705.01411 | Xiao-Hong Wu | Chao-Shang Huang, Wen-Jun Li, Xiao-Hong Wu | E6 GUT through Effects of Dimension-5 Operators | 20 pages, 10 tables, 8 figures, journal accepted version | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the effective field theory framework, quantum gravity can induce effective
dimension-5 operators, which have important impacts on grand unified theories.
Interestingly, one of main effects is the modification of the usual gauge
coupling unification condition. We investigate the gauge coupling unification
in $E_{6}$ under modified gauge coupling unification condition at scales $M_X$
in the presence of one or more dimension-5 operators. It is shown that
nonsupersymmetric models of $E_6$ unification can be obtained and can easily
satisfy the constraints from the proton lifetime. For constructing these
models, we consider several maximal subgroups $H=SO(10)\times U(1),
H=SU(3)\times SU(3)\times SU(3)$, and $H=SU(2)\times SU(6)$ of $E_{6}$ and the
usual breaking chains for a specific maximal subgroup, and derive all of the
Clebsch-Gordan coefficients $\Phi^{(r)}_{s,z}$ associated with $E_6$ breaking
to the Standard Model, which are given in Appendix A.
| [
{
"created": "Wed, 3 May 2017 13:27:14 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Jul 2017 12:36:04 GMT",
"version": "v2"
},
{
"created": "Wed, 8 Nov 2017 11:47:04 GMT",
"version": "v3"
}
] | 2017-11-09 | [
[
"Huang",
"Chao-Shang",
""
],
[
"Li",
"Wen-Jun",
""
],
[
"Wu",
"Xiao-Hong",
""
]
] | In the effective field theory framework, quantum gravity can induce effective dimension-5 operators, which have important impacts on grand unified theories. Interestingly, one of main effects is the modification of the usual gauge coupling unification condition. We investigate the gauge coupling unification in $E_{6}$ under modified gauge coupling unification condition at scales $M_X$ in the presence of one or more dimension-5 operators. It is shown that nonsupersymmetric models of $E_6$ unification can be obtained and can easily satisfy the constraints from the proton lifetime. For constructing these models, we consider several maximal subgroups $H=SO(10)\times U(1), H=SU(3)\times SU(3)\times SU(3)$, and $H=SU(2)\times SU(6)$ of $E_{6}$ and the usual breaking chains for a specific maximal subgroup, and derive all of the Clebsch-Gordan coefficients $\Phi^{(r)}_{s,z}$ associated with $E_6$ breaking to the Standard Model, which are given in Appendix A. |
2211.06656 | Egle Tomasi-Gustafsson | G.I. Gakh, M.I. Konchatnij, N.P. Merenkov, E. Tomasi-Gustafsson | Polarization phenomena in the reaction $e^+ + e^- \to p + \bar p +\pi^0$
in frame of the non-resonant mechanism | 18 pages, 10 figures | null | null | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | The dependence of the nucleon polarization in the reaction $e^+ + e^- \to N +
\bar{N} +\pi^0 $ over different invariant variables in frame of the
non-resonant mechanism, has been derived. The nucleon polarization is expressed
in terms of six invariant complex amplitudes, assuming the conservation of the
hadron electromagnetic currents and the P-invariance of the hadron
electromagnetic interaction. An inclusive experimental setup when the proton
(or the antiproton) and the pion are detected in coincidence is considered.
Numerical estimations were performed for the so called normal polarization in
the energy range from threshold up to $s=16$ GeV$^2$, using a specific
parametrization of the nucleon electromagnetic form factors and taking into
account the unpolarized differential cross section of the non-resonant
mechanism, as previously calculated.
| [
{
"created": "Sat, 12 Nov 2022 13:14:18 GMT",
"version": "v1"
}
] | 2022-11-15 | [
[
"Gakh",
"G. I.",
""
],
[
"Konchatnij",
"M. I.",
""
],
[
"Merenkov",
"N. P.",
""
],
[
"Tomasi-Gustafsson",
"E.",
""
]
] | The dependence of the nucleon polarization in the reaction $e^+ + e^- \to N + \bar{N} +\pi^0 $ over different invariant variables in frame of the non-resonant mechanism, has been derived. The nucleon polarization is expressed in terms of six invariant complex amplitudes, assuming the conservation of the hadron electromagnetic currents and the P-invariance of the hadron electromagnetic interaction. An inclusive experimental setup when the proton (or the antiproton) and the pion are detected in coincidence is considered. Numerical estimations were performed for the so called normal polarization in the energy range from threshold up to $s=16$ GeV$^2$, using a specific parametrization of the nucleon electromagnetic form factors and taking into account the unpolarized differential cross section of the non-resonant mechanism, as previously calculated. |
hep-ph/0309287 | Andrei Rostovtsev | A.Kropivnitskaya, A.Rostovtsev | R\'enyi statistics in high energy particle production | 9pages, 3 figures | null | null | null | hep-ph | null | It is shown that R\'enyi statistics provides a plausible basis to describe
the hadron distributions measured in high energy particle interactions.
Generalized Boltzmann and gamma distributions obtained by maximization of
R\'enyi entropy under constraints on Kolmogorov-Nagumo averages are used to
describe the hadron transverse momentum and multiplicity spectra
correspondingly.
| [
{
"created": "Thu, 25 Sep 2003 13:26:04 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Oct 2003 13:20:22 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Kropivnitskaya",
"A.",
""
],
[
"Rostovtsev",
"A.",
""
]
] | It is shown that R\'enyi statistics provides a plausible basis to describe the hadron distributions measured in high energy particle interactions. Generalized Boltzmann and gamma distributions obtained by maximization of R\'enyi entropy under constraints on Kolmogorov-Nagumo averages are used to describe the hadron transverse momentum and multiplicity spectra correspondingly. |
1908.11730 | Volodymyr Vovchenko | Anton Motornenko, Volodymyr Vovchenko, Carsten Greiner, Horst Stoecker | Kinetic freeze-out temperature from yields of short-lived resonances | 6 pages, 3 figures. Version published in Physical Review C | Phys. Rev. C 102, 024909 (2020) | 10.1103/PhysRevC.102.024909 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A method to determine the kinetic freeze-out temperature in heavy-ion
collisions from measured yields of short-lived resonances is presented. The
resonance production is treated in the framework of thermal model with an
evolution between chemical and kinetic freeze-outs. The yields of many
short-lived resonances are suppressed at $T = T_{\rm kin} < T_{\rm ch}$. We
determine the values of $T_{\rm kin}$ and $T_{\rm ch}$ for various centralities
in Pb--Pb collisions at $\sqrt{s_{_{NN}}} = 2.76$ TeV by fitting the abundances
of both the stable hadrons and the short-lived resonances such as $\rho^0$ and
$ \text{K}^{*0}$, that were measured by the ALICE collaboration. This allows to
extract the kinetic freeze-out temperature from the measured hadron and
resonance yields alone, independent of assumptions about the flow velocity
profile and the freeze-out hypersurface. The extracted $T_{\rm ch}$ values
exhibit a moderate multiplicity dependence whereas $T_{\rm kin}$ drops, from
$T_{\rm kin} \simeq T_{\rm ch} \simeq 155$ MeV in peripheral collisions to
$T_{\rm kin} \simeq 110$ MeV in 0-20% central collisions. Predictions for other
short-lived resonances are presented. A potential (non-)observation of a
suppressed $f_0(980)$ meson yield will allow to constrain the lifetime of that
meson.
| [
{
"created": "Fri, 30 Aug 2019 13:29:57 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Sep 2019 12:45:52 GMT",
"version": "v2"
},
{
"created": "Thu, 13 Aug 2020 17:26:38 GMT",
"version": "v3"
}
] | 2020-08-14 | [
[
"Motornenko",
"Anton",
""
],
[
"Vovchenko",
"Volodymyr",
""
],
[
"Greiner",
"Carsten",
""
],
[
"Stoecker",
"Horst",
""
]
] | A method to determine the kinetic freeze-out temperature in heavy-ion collisions from measured yields of short-lived resonances is presented. The resonance production is treated in the framework of thermal model with an evolution between chemical and kinetic freeze-outs. The yields of many short-lived resonances are suppressed at $T = T_{\rm kin} < T_{\rm ch}$. We determine the values of $T_{\rm kin}$ and $T_{\rm ch}$ for various centralities in Pb--Pb collisions at $\sqrt{s_{_{NN}}} = 2.76$ TeV by fitting the abundances of both the stable hadrons and the short-lived resonances such as $\rho^0$ and $ \text{K}^{*0}$, that were measured by the ALICE collaboration. This allows to extract the kinetic freeze-out temperature from the measured hadron and resonance yields alone, independent of assumptions about the flow velocity profile and the freeze-out hypersurface. The extracted $T_{\rm ch}$ values exhibit a moderate multiplicity dependence whereas $T_{\rm kin}$ drops, from $T_{\rm kin} \simeq T_{\rm ch} \simeq 155$ MeV in peripheral collisions to $T_{\rm kin} \simeq 110$ MeV in 0-20% central collisions. Predictions for other short-lived resonances are presented. A potential (non-)observation of a suppressed $f_0(980)$ meson yield will allow to constrain the lifetime of that meson. |
2212.08579 | Shuzhe Shi | Anping Huang, Duan She, Shuzhe Shi, Mei Huang, Jinfeng Liao | Dynamical magnetic fields in heavy-ion collisions | 15 pages, 7 figures | Phys. Rev. C 107 (2023) 034901 | 10.1103/PhysRevC.107.034901 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The magnetic fields in heavy-ion collisions are important ingredients for
many interesting phenomena, such as the Chiral Magnetic Effect, Chiral Magnetic
Wave, the directed flow $v_1$ of $D^0$ mesons and the splitting of the spin
polarization of the $\Lambda$/$\bar{\Lambda}$. Quantitative studies of these
phenomena however suffer from limited understanding on the dynamical evolution
of these fields in the medium created by the collisions, which remains a
critical and challenging problem. The initial magnetic fields from the
colliding nuclei decay very fast in the vacuum but their lifetime could be
extended through medium response due to electrically conducting quarks and
antiquarks. Here we perform a detailed analysis of such medium effect on the
dynamical magnetic fields by numerically solving the Maxwell's equations
concurrently with the expanding medium described by viscous hydrodynamics,
under the assumption of negligible back reaction of the fields on the fluid
evolution. Our results suggest a considerable enhancement of late time magnetic
fields, the magnitude of which depends sensitively on the fireball expansion as
well as the medium electric conductivity both before and during hydrodynamic
stage.
| [
{
"created": "Fri, 16 Dec 2022 16:55:57 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Apr 2023 01:56:23 GMT",
"version": "v2"
}
] | 2023-04-10 | [
[
"Huang",
"Anping",
""
],
[
"She",
"Duan",
""
],
[
"Shi",
"Shuzhe",
""
],
[
"Huang",
"Mei",
""
],
[
"Liao",
"Jinfeng",
""
]
] | The magnetic fields in heavy-ion collisions are important ingredients for many interesting phenomena, such as the Chiral Magnetic Effect, Chiral Magnetic Wave, the directed flow $v_1$ of $D^0$ mesons and the splitting of the spin polarization of the $\Lambda$/$\bar{\Lambda}$. Quantitative studies of these phenomena however suffer from limited understanding on the dynamical evolution of these fields in the medium created by the collisions, which remains a critical and challenging problem. The initial magnetic fields from the colliding nuclei decay very fast in the vacuum but their lifetime could be extended through medium response due to electrically conducting quarks and antiquarks. Here we perform a detailed analysis of such medium effect on the dynamical magnetic fields by numerically solving the Maxwell's equations concurrently with the expanding medium described by viscous hydrodynamics, under the assumption of negligible back reaction of the fields on the fluid evolution. Our results suggest a considerable enhancement of late time magnetic fields, the magnitude of which depends sensitively on the fireball expansion as well as the medium electric conductivity both before and during hydrodynamic stage. |
hep-ph/0503122 | Jake Lee | Kingman Cheung (Tsing Hua U.), Sin Kyu Kang (SNU), C. S. Kim, Jake Lee
(Yonsei U.) | Lepton Flavor Violation as a Probe of Quark-Lepton Unification | 10 pages, no figures | Phys.Rev. D72 (2005) 036003 | 10.1103/PhysRevD.72.036003 | null | hep-ph | null | The recent measurements of the solar neutrino mixing angle theta_{sol} and
the Cabibbo mixing angle theta_C reveal a surprising relation,
theta_{sol}+theta_C ~ pi/4. Interpreting this empirical relation as a support
of the quark-lepton unification, we find that the PMNS mixing matrix can be
decomposed into a CKM-like matrix and maximal mixing matrices, which can give
profound implications on the quark-lepton unification. We explore a possibility
to probe the implication of quark-lepton unification by considering the
relative sizes of branching ratios for the lepton flavor violating radiative
decay processes, l_i-->l_j gamma, in the context of the supersymmetric standard
model with heavy right-handed Majorana neutrinos.
| [
{
"created": "Mon, 14 Mar 2005 05:23:22 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Cheung",
"Kingman",
"",
"Tsing Hua U."
],
[
"Kang",
"Sin Kyu",
"",
"SNU"
],
[
"Kim",
"C. S.",
"",
"Yonsei U."
],
[
"Lee",
"Jake",
"",
"Yonsei U."
]
] | The recent measurements of the solar neutrino mixing angle theta_{sol} and the Cabibbo mixing angle theta_C reveal a surprising relation, theta_{sol}+theta_C ~ pi/4. Interpreting this empirical relation as a support of the quark-lepton unification, we find that the PMNS mixing matrix can be decomposed into a CKM-like matrix and maximal mixing matrices, which can give profound implications on the quark-lepton unification. We explore a possibility to probe the implication of quark-lepton unification by considering the relative sizes of branching ratios for the lepton flavor violating radiative decay processes, l_i-->l_j gamma, in the context of the supersymmetric standard model with heavy right-handed Majorana neutrinos. |
2309.06292 | Ming-Ming Long | Christian Br{\o}nnum-Hansen, Ming-Ming Long, Kirill Melnikov | Scale dependence of non-factorizable virtual corrections to Higgs boson
production in weak boson fusion | 14 pages, 7 figures, version accepted by JHEP | null | null | TTP23-036, P3H-23-060 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The renormalization-scale dependence of the non-factorizable virtual
corrections to Higgs boson production in weak boson fusion at
next-to-next-to-leading order in perturbative QCD is unusually strong, due to
the peculiar nature of these corrections. To address this problem, we compute
the three-loop non-factorizable contribution to this process which accounts for
the running of the strong coupling constant, and show that it stabilizes the
theoretical prediction.
| [
{
"created": "Tue, 12 Sep 2023 14:56:56 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Nov 2023 10:08:16 GMT",
"version": "v2"
}
] | 2023-11-10 | [
[
"Brønnum-Hansen",
"Christian",
""
],
[
"Long",
"Ming-Ming",
""
],
[
"Melnikov",
"Kirill",
""
]
] | The renormalization-scale dependence of the non-factorizable virtual corrections to Higgs boson production in weak boson fusion at next-to-next-to-leading order in perturbative QCD is unusually strong, due to the peculiar nature of these corrections. To address this problem, we compute the three-loop non-factorizable contribution to this process which accounts for the running of the strong coupling constant, and show that it stabilizes the theoretical prediction. |
2108.13894 | Jamie McDonald | J. I. McDonald | Scanning the landscape of axion dark matter detectors: applying gradient
descent to experimental design | 6 pages, 3 figures, comments welcome | null | 10.1103/PhysRevD.105.083010 | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | The hunt for dark matter remains one of the principal objectives of modern
physics and cosmology. Searches for dark matter in the form of axions are
proposed or underway across a range of experimental collaborations. As we look
to the next generation of detectors, a natural question to ask is whether there
are new experimental designs waiting to be discovered and how we might find
them. Here we take a new approach to the experimental design procedure by using
gradient descent techniques to search for optimal detector designs. We provide
a proof of principle for this technique by searching 1D detectors varying the
bulk properties of the detector until the optimal detector design is obtained.
Remarkably, we find the detector is capable of out-performing a human designed
experiment on which the search was initiated. This opens the door to further
gradient descent searches of more complex 2D and 3D designs across a wider
variety of materials and boundary geometries of the detector. There is also an
opportunity to use more sophisticated gradient descent algorithms to complete a
more exhaustive scan of the landscape of designs.
| [
{
"created": "Tue, 31 Aug 2021 14:51:15 GMT",
"version": "v1"
}
] | 2022-05-04 | [
[
"McDonald",
"J. I.",
""
]
] | The hunt for dark matter remains one of the principal objectives of modern physics and cosmology. Searches for dark matter in the form of axions are proposed or underway across a range of experimental collaborations. As we look to the next generation of detectors, a natural question to ask is whether there are new experimental designs waiting to be discovered and how we might find them. Here we take a new approach to the experimental design procedure by using gradient descent techniques to search for optimal detector designs. We provide a proof of principle for this technique by searching 1D detectors varying the bulk properties of the detector until the optimal detector design is obtained. Remarkably, we find the detector is capable of out-performing a human designed experiment on which the search was initiated. This opens the door to further gradient descent searches of more complex 2D and 3D designs across a wider variety of materials and boundary geometries of the detector. There is also an opportunity to use more sophisticated gradient descent algorithms to complete a more exhaustive scan of the landscape of designs. |
1006.5013 | Christoph Bobeth | Christoph Bobeth, Gudrun Hiller and Danny van Dyk | The Benefits of B ---> K* l+ l- Decays at Low Recoil | 31 pages, 8 figures; Instability near minimal recoil from numerics
removed, Fig. 1 replaced and minor shifts in short distance uncertainties in
SM predictions; typos corrected and references added; main results and
conclusions unchanged | JHEP 1007:098,2010 | 10.1007/JHEP07(2010)098 | CERN-PH-TH-2010-134, DO-TH 10/08 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the heavy quark effective theory framework put forward by Grinstein and
Pirjol we work out predictions for B -> K* l+ l-, l = (e, mu), decays for a
softly recoiling K*, i.e., for large dilepton masses sqrt{q^2} of the order of
the b-quark mass m_b. We work to lowest order in Lambda/Q, where Q = (m_b,
sqrt{q^2}) and include the next-to-leading order corrections from the charm
quark mass m_c and the strong coupling at O(m_c^2/Q^2, alpha_s). The leading
Lambda/m_b corrections are parametrically suppressed. The improved Isgur-Wise
form factor relations correlate the B -> K* l+ l- transversity amplitudes,
which simplifies the description of the various decay observables and provides
opportunities for the extraction of the electroweak short distance couplings.
We propose new angular observables which have very small hadronic
uncertainties. We exploit existing data on B -> K* l+ l- distributions and show
that the low recoil region provides powerful additional information to the
large recoil one. We find disjoint best-fit solutions, which include the
Standard Model, but also beyond-the-Standard Model ones. This ambiguity can be
accessed with future precision measurements.
| [
{
"created": "Fri, 25 Jun 2010 15:50:41 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Jul 2010 12:15:20 GMT",
"version": "v2"
}
] | 2014-11-21 | [
[
"Bobeth",
"Christoph",
""
],
[
"Hiller",
"Gudrun",
""
],
[
"van Dyk",
"Danny",
""
]
] | Using the heavy quark effective theory framework put forward by Grinstein and Pirjol we work out predictions for B -> K* l+ l-, l = (e, mu), decays for a softly recoiling K*, i.e., for large dilepton masses sqrt{q^2} of the order of the b-quark mass m_b. We work to lowest order in Lambda/Q, where Q = (m_b, sqrt{q^2}) and include the next-to-leading order corrections from the charm quark mass m_c and the strong coupling at O(m_c^2/Q^2, alpha_s). The leading Lambda/m_b corrections are parametrically suppressed. The improved Isgur-Wise form factor relations correlate the B -> K* l+ l- transversity amplitudes, which simplifies the description of the various decay observables and provides opportunities for the extraction of the electroweak short distance couplings. We propose new angular observables which have very small hadronic uncertainties. We exploit existing data on B -> K* l+ l- distributions and show that the low recoil region provides powerful additional information to the large recoil one. We find disjoint best-fit solutions, which include the Standard Model, but also beyond-the-Standard Model ones. This ambiguity can be accessed with future precision measurements. |
1302.3374 | Namit Mahajan | Namit Mahajan | On non-minimal coupling of the inflaton | 10 pages | null | 10.1142/S021827181450076X | null | hep-ph astro-ph.CO gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The non-minimal coupling of the inflaton to gravity, $\xi R\phi^2$, is known
to alleviate the smallness (fine-tuning) of the quartic coupling $\lambda$ in
the chaotic inflation with $\phi^4$ potential. A large $\xi$ is required to
obtain the correct CMB power spectrum while we find that a small value $\sim
1/6$ seems to be preferred from spectral index. There are issues related to
conformal transformations, choice of frame and natural value(s) of $\xi$ for a
given potential. We revisit some of these issues and invoke certain field
theoretic arguments in order to address the same. A rather strong and general
conclusion reached, based on the requirements of renormalizability and
finiteness of specific matrix elements in a quantum theory, is that it is
generically not possible to eliminate the non-minimal coupling by going from
the Jordan to the Einstein frame via conformal transformations. We also comment
on Higgs inflation.
| [
{
"created": "Thu, 14 Feb 2013 11:30:35 GMT",
"version": "v1"
}
] | 2015-06-15 | [
[
"Mahajan",
"Namit",
""
]
] | The non-minimal coupling of the inflaton to gravity, $\xi R\phi^2$, is known to alleviate the smallness (fine-tuning) of the quartic coupling $\lambda$ in the chaotic inflation with $\phi^4$ potential. A large $\xi$ is required to obtain the correct CMB power spectrum while we find that a small value $\sim 1/6$ seems to be preferred from spectral index. There are issues related to conformal transformations, choice of frame and natural value(s) of $\xi$ for a given potential. We revisit some of these issues and invoke certain field theoretic arguments in order to address the same. A rather strong and general conclusion reached, based on the requirements of renormalizability and finiteness of specific matrix elements in a quantum theory, is that it is generically not possible to eliminate the non-minimal coupling by going from the Jordan to the Einstein frame via conformal transformations. We also comment on Higgs inflation. |
2402.06595 | Laura Tolos | Jose Luis Hernandez, Cristina Manuel and Laura Tolos | Damping of density oscillations from bulk viscosity in quark matter | 12 pages, 9 figures, 7 tables, published revised version | Phys. Rev. D 109 (2024) 123022 | 10.1103/PhysRevD.109.123022 | null | hep-ph astro-ph.HE nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the damping of density oscillations in the quark matter phase that
might occur in compact stars. To this end we compute the bulk viscosity and the
associated damping time in three-flavor quark matter, considering both
nonleptonic and semileptonic electroweak processes. We use two different
equations of state of quark matter, more precisely, the MIT bag model and
perturbative QCD, including the leading-order corrections in the strong
coupling constant. We analyze the dependence of our results on the density,
temperature and value of strange quark mass in each case. We then find that the
maximum of the bulk viscosity is in the range of temperature from 0.01 to 0.1
MeV for frequencies around 1 kHz, while the associated minimal damping times of
the density oscillations at those temperatures might be in the range of few to
hundreds milliseconds. Our results suggest that bulk viscous damping might be
relevant in the postmerger phase after the collision of two neutron stars if
deconfined matter is achieved in the process.
| [
{
"created": "Fri, 9 Feb 2024 18:16:44 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Jun 2024 21:42:53 GMT",
"version": "v2"
}
] | 2024-06-28 | [
[
"Hernandez",
"Jose Luis",
""
],
[
"Manuel",
"Cristina",
""
],
[
"Tolos",
"Laura",
""
]
] | We study the damping of density oscillations in the quark matter phase that might occur in compact stars. To this end we compute the bulk viscosity and the associated damping time in three-flavor quark matter, considering both nonleptonic and semileptonic electroweak processes. We use two different equations of state of quark matter, more precisely, the MIT bag model and perturbative QCD, including the leading-order corrections in the strong coupling constant. We analyze the dependence of our results on the density, temperature and value of strange quark mass in each case. We then find that the maximum of the bulk viscosity is in the range of temperature from 0.01 to 0.1 MeV for frequencies around 1 kHz, while the associated minimal damping times of the density oscillations at those temperatures might be in the range of few to hundreds milliseconds. Our results suggest that bulk viscous damping might be relevant in the postmerger phase after the collision of two neutron stars if deconfined matter is achieved in the process. |
hep-ph/9508284 | Alexander Yelkhovsky | A. Yelkhovsky | Order (Z\alpha)^4 m/M Ry Correction to Hydrogen Levels | 14 pages, LaTeX. Extended version with updated references. Minor
errors corrected, final results unchanged | null | null | BudkerINP-95-63 | hep-ph | null | The first in m/M and fourth in Z\alpha (pure recoil) correction to a hydrogen
energy level is found. This correction comprises two contributions, one coming
from the atomic scale, the other from distances of the Compton wavelength
order. Two different perturbation schemes are used to calculate the former. One
of them exploits as unperturbed the solution to the Dirac-Coulomb problem, the
nucleus' slow motion being the source of the perturbation. The alternative
scheme treats both the electron and the nucleus as slow, while relativistic
effects are considered perturbatively. The short-distance contribution is found
in the Feynman and Coulomb gauges. Recent results for P levels are confirmed,
in contrast with those for S levels. Numerically, the shift equals 2.77 kHz for
the ground state and 0.51 kHz for 2S state.
| [
{
"created": "Fri, 11 Aug 1995 07:35:01 GMT",
"version": "v1"
},
{
"created": "Sat, 25 Nov 1995 06:46:32 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Yelkhovsky",
"A.",
""
]
] | The first in m/M and fourth in Z\alpha (pure recoil) correction to a hydrogen energy level is found. This correction comprises two contributions, one coming from the atomic scale, the other from distances of the Compton wavelength order. Two different perturbation schemes are used to calculate the former. One of them exploits as unperturbed the solution to the Dirac-Coulomb problem, the nucleus' slow motion being the source of the perturbation. The alternative scheme treats both the electron and the nucleus as slow, while relativistic effects are considered perturbatively. The short-distance contribution is found in the Feynman and Coulomb gauges. Recent results for P levels are confirmed, in contrast with those for S levels. Numerically, the shift equals 2.77 kHz for the ground state and 0.51 kHz for 2S state. |
1005.0045 | Anjan Joshipura | Anjan S. Joshipura and Ketan M. Patel | Quasi-degenerate neutrinos in SO(10) | 12 pages | Phys.Rev.D82:031701,2010 | 10.1103/PhysRevD.82.031701 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Quark lepton universality inherent in grand unified theories based on
$SO(10)$ gauge group generically leads to hierarchical neutrino masses. We
propose a specific ansatz for the structure of Yukawa matrices in $SO(10)$
models which differ from this generic expectations and lead to quasi degenerate
neutrinos through the type-I seesaw mechanism. Consistency of this ansatz is
demonstrated through a detailed fits to fermion masses and mixing angles all of
which can be explained with reasonable accuracy in a model which uses the Higgs
fields transforming as $10,120$ and $\overline{126}$ representations of
$SO(10)$. The proposed ansatz is shown to follow from an extended model based
on the three generations of the vector like fermions and an $O(3)$ flavour
symmetry. Successful numerical fits are also discussed in earlier proposed
models which used combination of the type-I and type-II seesaw mechanisms for
obtaining quasi degenerate neutrinos. Large neutrino mixing angles emerge as a
consequence of neutrino mass degeneracy in both these cases.
| [
{
"created": "Sat, 1 May 2010 04:11:11 GMT",
"version": "v1"
}
] | 2015-03-17 | [
[
"Joshipura",
"Anjan S.",
""
],
[
"Patel",
"Ketan M.",
""
]
] | Quark lepton universality inherent in grand unified theories based on $SO(10)$ gauge group generically leads to hierarchical neutrino masses. We propose a specific ansatz for the structure of Yukawa matrices in $SO(10)$ models which differ from this generic expectations and lead to quasi degenerate neutrinos through the type-I seesaw mechanism. Consistency of this ansatz is demonstrated through a detailed fits to fermion masses and mixing angles all of which can be explained with reasonable accuracy in a model which uses the Higgs fields transforming as $10,120$ and $\overline{126}$ representations of $SO(10)$. The proposed ansatz is shown to follow from an extended model based on the three generations of the vector like fermions and an $O(3)$ flavour symmetry. Successful numerical fits are also discussed in earlier proposed models which used combination of the type-I and type-II seesaw mechanisms for obtaining quasi degenerate neutrinos. Large neutrino mixing angles emerge as a consequence of neutrino mass degeneracy in both these cases. |
2201.10427 | Yongseok Oh | Ahmad Jafar Arifi, Daiki Suenaga, Atsushi Hosaka, Yongseok Oh | Strong decays of multi-strangeness baryon resonances in the quark model | 15 pages, 12 figures, 10 tables | null | null | null | hep-ph hep-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | Decay properties of multi-strangeness $\Xi$ and $\Omega$ baryon resonances
are investigated within the constituent quark model by including relativistic
corrections. The strong decay widths of various $\Xi$ and $\Omega$ resonances
are computed and tested for internal quark configurations to pin down their
spin-parity ($J^P$) quantum numbers and internal structures. We found that the
Roper-like resonances in the multi-strangeness sector have large decay widths
bearing resemblances to their siblings in light and heavy baryon sectors. In
addition, we obtained the decay ratio for the $\Omega(2012)$ as
$\Gamma{(\Omega\to \Xi \bar{K} \pi)} / \Gamma{(\Omega\to \Xi \bar{K})}=4.5\%$,
which is consistent with the experimental data when $J^P=3/2^-$ is assigned.
This observation holds the possibility that the $\Omega(2012)$ could naturally
be explained as a three-quark state in the quark model. The decays of other
low-lying $\Xi$ and $\Omega$ resonances are systematically analyzed, which
would be useful to unveil the structure of these resonances in future
experiments.
| [
{
"created": "Tue, 25 Jan 2022 16:25:11 GMT",
"version": "v1"
}
] | 2022-01-26 | [
[
"Arifi",
"Ahmad Jafar",
""
],
[
"Suenaga",
"Daiki",
""
],
[
"Hosaka",
"Atsushi",
""
],
[
"Oh",
"Yongseok",
""
]
] | Decay properties of multi-strangeness $\Xi$ and $\Omega$ baryon resonances are investigated within the constituent quark model by including relativistic corrections. The strong decay widths of various $\Xi$ and $\Omega$ resonances are computed and tested for internal quark configurations to pin down their spin-parity ($J^P$) quantum numbers and internal structures. We found that the Roper-like resonances in the multi-strangeness sector have large decay widths bearing resemblances to their siblings in light and heavy baryon sectors. In addition, we obtained the decay ratio for the $\Omega(2012)$ as $\Gamma{(\Omega\to \Xi \bar{K} \pi)} / \Gamma{(\Omega\to \Xi \bar{K})}=4.5\%$, which is consistent with the experimental data when $J^P=3/2^-$ is assigned. This observation holds the possibility that the $\Omega(2012)$ could naturally be explained as a three-quark state in the quark model. The decays of other low-lying $\Xi$ and $\Omega$ resonances are systematically analyzed, which would be useful to unveil the structure of these resonances in future experiments. |
hep-ph/0308223 | Ulrich Jentschura | S. R. Valluri, U. D. Jentschura, D. R. Lamm | The Study of the Heisenberg-Euler Lagrangian and Some of its
Applications | 12 pages, LaTeX; Proceedings of the MRST-2003 conference; talk given
by S. R. Valluri | AIP Conf.Proc. 687 (2003) 203-214 | 10.1063/1.1632189 | null | hep-ph hep-th | null | The Heisenberg-Euler Lagrangian is not only a topic of fundamental interest,
but also has a rich variety of diverse applications in astrophysics, nonlinear
optics and elementary particle physics etc. We discuss the series
representation of this Lagrangian and a few of its applications in this study.
[In an appendix, we discuss issues related to the renormalization - and the
renormalization-group invariance - of the Heisenberg-Euler Lagrangian and its
two-loop generalization.]
| [
{
"created": "Thu, 21 Aug 2003 20:46:46 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Valluri",
"S. R.",
""
],
[
"Jentschura",
"U. D.",
""
],
[
"Lamm",
"D. R.",
""
]
] | The Heisenberg-Euler Lagrangian is not only a topic of fundamental interest, but also has a rich variety of diverse applications in astrophysics, nonlinear optics and elementary particle physics etc. We discuss the series representation of this Lagrangian and a few of its applications in this study. [In an appendix, we discuss issues related to the renormalization - and the renormalization-group invariance - of the Heisenberg-Euler Lagrangian and its two-loop generalization.] |
hep-ph/0409084 | Mitsuo J. Hayashi | Mitsuo J. Hayashi and Tomoki Watanabe | Dilatonic Inflation and SUSY Breaking in Modular-Invariant Supergravity | 4pages, 4 eps figures, talk at ICHEP2004, Aug. 16-22, 2004, Beijing | null | 10.1142/9789812702227_0062 | null | hep-ph | null | The theory of inflation will be investigated as well as supersymmetry
breaking in the context of supergravity, incorporating the target-space duality
and the non-perturbative gaugino condensation in the hidden sector. The
inflation and supersymmetry breaking occur at once by the interplay between the
dilaton field as inflaton and the condensate gauge-singlet field. The model
satisfies the slow-roll condition which solves the eta-problem. When the
particle rolls down along the minimized trajectry of the potential V(S,Y) at a
duality invariant fixed point T=1, we can obtain the e-fold value \sim 57. And
then the cosmological parameters obtained from our model well match with the
recent WMAP data combined with other experiments. This observation is
suggesting to consider the string-inspired supergravity as the fundamental of
the theory of the evolution of the universe as well as the particle theory.
| [
{
"created": "Wed, 8 Sep 2004 06:20:46 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Hayashi",
"Mitsuo J.",
""
],
[
"Watanabe",
"Tomoki",
""
]
] | The theory of inflation will be investigated as well as supersymmetry breaking in the context of supergravity, incorporating the target-space duality and the non-perturbative gaugino condensation in the hidden sector. The inflation and supersymmetry breaking occur at once by the interplay between the dilaton field as inflaton and the condensate gauge-singlet field. The model satisfies the slow-roll condition which solves the eta-problem. When the particle rolls down along the minimized trajectry of the potential V(S,Y) at a duality invariant fixed point T=1, we can obtain the e-fold value \sim 57. And then the cosmological parameters obtained from our model well match with the recent WMAP data combined with other experiments. This observation is suggesting to consider the string-inspired supergravity as the fundamental of the theory of the evolution of the universe as well as the particle theory. |
1503.06339 | Dmitry Levkov | Sergei Demidov and Dmitry Levkov | High-energy limit of collision-induced false vacuum decay | 33 pages, 14 figures; journal version | JHEP 06 (2015) 123 | null | INR-TH-2015-009 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We develop a consistent semiclassical description of field-theoretic
collision-induced tunneling at arbitrary high collision energies. As a
playground we consider a (1+1)-dimensional false vacuum decay initiated by a
collision of N particles at energy E, paying special attention to the realistic
case of N=2 particles. We demonstrate that the cross section of this process is
exponentially suppressed at all energies. Moreover, the respective
suppressesion exponent F_N(E) exhibits a specific behavior which is significant
for our semiclassical method and assumed to be general: it decreases with
energy, reaches absolute minimum F=F_min(N) at a certain threshold energy
E=E_rt(N), and stays constant at higher energies. We show that the minimal
suppression F_min(N) and threshold energy can be evaluated using a special
class of semiclassical solutions which describe exponentially suppressed
transitions but nevertheless evolve in real time. Importantly, we argue that
the cross section at energies above E_rt(N) is computed perturbatively in the
background of the latter solutions, and the terms of this perturbative
expansion stay bounded in the infinite-energy limit. Transitions in the
high-energy regime proceed via emission of many soft quanta with total energy
E_rt; the energy excess E-E_rt remains in the colliding particles till the end
of the process.
| [
{
"created": "Sat, 21 Mar 2015 19:13:00 GMT",
"version": "v1"
},
{
"created": "Tue, 19 May 2015 19:35:47 GMT",
"version": "v2"
}
] | 2015-06-23 | [
[
"Demidov",
"Sergei",
""
],
[
"Levkov",
"Dmitry",
""
]
] | We develop a consistent semiclassical description of field-theoretic collision-induced tunneling at arbitrary high collision energies. As a playground we consider a (1+1)-dimensional false vacuum decay initiated by a collision of N particles at energy E, paying special attention to the realistic case of N=2 particles. We demonstrate that the cross section of this process is exponentially suppressed at all energies. Moreover, the respective suppressesion exponent F_N(E) exhibits a specific behavior which is significant for our semiclassical method and assumed to be general: it decreases with energy, reaches absolute minimum F=F_min(N) at a certain threshold energy E=E_rt(N), and stays constant at higher energies. We show that the minimal suppression F_min(N) and threshold energy can be evaluated using a special class of semiclassical solutions which describe exponentially suppressed transitions but nevertheless evolve in real time. Importantly, we argue that the cross section at energies above E_rt(N) is computed perturbatively in the background of the latter solutions, and the terms of this perturbative expansion stay bounded in the infinite-energy limit. Transitions in the high-energy regime proceed via emission of many soft quanta with total energy E_rt; the energy excess E-E_rt remains in the colliding particles till the end of the process. |
0711.1821 | Lawrence M. Krauss | Lawrence M. Krauss (1,2) and James Dent (2) ((1) Case Western Reserve
University, (2) Vanderbilt University) | The Late Time Behavior of False Vacuum Decay: Possible Implications for
Cosmology and Metastable Inflating States | 4 pages, submitted to PRL, one reference changed, and changes to
abstract and concluding sentences to stem possible confusions regarding
observation and metastability | Phys.Rev.Lett.100:171301,2008 | 10.1103/PhysRevLett.100.171301 | null | hep-ph astro-ph hep-th | null | We describe here how the late time behavior of the decaying states, which is
predicted to deviate from an exponential form, while normally of insignificant
consequence, may have important cosmological implications in the case of false
vacuum decay. It may increase the likelihood of eternal inflation, and may help
explain the likelihood of observing a small vacuum energy at late times, as
well as arguing against decay into a large negative energy (anti-de Sitter
space), vacuum state as has been motivated by some string theory
considerations. Several interesting open questions are raised, including
whether observing the cosmological configuration of a metastable universe can
constrain its inferred lifetime.
| [
{
"created": "Mon, 12 Nov 2007 17:18:45 GMT",
"version": "v1"
},
{
"created": "Sat, 24 Nov 2007 23:37:31 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Krauss",
"Lawrence M.",
""
],
[
"Dent",
"James",
""
]
] | We describe here how the late time behavior of the decaying states, which is predicted to deviate from an exponential form, while normally of insignificant consequence, may have important cosmological implications in the case of false vacuum decay. It may increase the likelihood of eternal inflation, and may help explain the likelihood of observing a small vacuum energy at late times, as well as arguing against decay into a large negative energy (anti-de Sitter space), vacuum state as has been motivated by some string theory considerations. Several interesting open questions are raised, including whether observing the cosmological configuration of a metastable universe can constrain its inferred lifetime. |
hep-ph/9409357 | J. Gunion | J.F. Gunion, J.G. Kelly, and J. Ohnemus | Detection of Minimal Supersymmetric Model Higgs Bosons in $\gam\gam$
Collisions: Influence of SUSY Decay Modes | 12 pages, requires phyzzx.tex and tables.tex, full postscript file
including embedded tables available via anonymous ftp at ucdhep.ucdavis.edu
as [anonymous.gunion]gamgamsusy.ps, preprint UCD-94-35 | Phys.Rev. D51 (1995) 2101-2107 | 10.1103/PhysRevD.51.2101 | null | hep-ph | null | We demonstrate that supersymmetric decay modes of the neutral Higgs bosons of
the MSSM could well make their detection extremely difficult when produced
singly in $\gam\gam$ collisions at a back-scattered laser beam facility.
| [
{
"created": "Tue, 20 Sep 1994 02:00:18 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Gunion",
"J. F.",
""
],
[
"Kelly",
"J. G.",
""
],
[
"Ohnemus",
"J.",
""
]
] | We demonstrate that supersymmetric decay modes of the neutral Higgs bosons of the MSSM could well make their detection extremely difficult when produced singly in $\gam\gam$ collisions at a back-scattered laser beam facility. |
2212.00631 | Teng Ji | Teng Ji, Xiang-Kun Dong, Miguel Albaladejo, Meng-Lin Du, Feng-Kun Guo,
Juan Nieves and Bing-Song Zou | Understanding the $0^{++}$ and $2^{++}$ charmonium(-like) states near
3.9 GeV | 15 pages, 6 figures, 2 tables, to apear in Sci. Bull | Science Bulletin, 2023, 68(7):688-697 | 10.1016/j.scib.2023.02.034 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose that the $X(3915)$ observed in the $J/\psi\,\omega$ channel is the
same state as the $\chi_{c2}(3930)$, and the $X(3960)$, observed in the
$D_s^+D_s^-$ channel, is an $S$-wave $D_s^+ D_s^-$ hadronic molecule. In
addition, the $J^{PC}=0^{++}$ {component in the $B^+\to D^+D^-K^+$} assigned to
the $X(3915)$ in the current {\it Review of Particle Physics} has the same
origin as the $X(3960)$, which has a mass around 3.94~GeV. To check the
proposal, the available data in the $D\bar D$ and $D_s^+ D_s^-$ channels from
both $ B$ decays and $\gamma\gamma$ fusion reaction are analyzed considering
both the $D\bar D$-$D_s\bar D_s$-$D^*\bar D^*$-$D_s^*\bar D_s^*$ coupled
channels with $0^{++}$ and a $2^{++}$ state introduced additionally. It is
found that all the data in different processes can be simultaneously well
reproduced, and the coupled-channel dynamics produce four hidden-charm scalar
molecular states with masses around 3.73, 3.94, 3.99 and 4.23~GeV,
respectively. The results may deepen our understanding of the spectrum of
charmonia as well as of the interactions between charmed hadrons.
| [
{
"created": "Thu, 1 Dec 2022 16:29:53 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Mar 2023 10:32:03 GMT",
"version": "v2"
}
] | 2023-09-14 | [
[
"Ji",
"Teng",
""
],
[
"Dong",
"Xiang-Kun",
""
],
[
"Albaladejo",
"Miguel",
""
],
[
"Du",
"Meng-Lin",
""
],
[
"Guo",
"Feng-Kun",
""
],
[
"Nieves",
"Juan",
""
],
[
"Zou",
"Bing-Song",
""
]
] | We propose that the $X(3915)$ observed in the $J/\psi\,\omega$ channel is the same state as the $\chi_{c2}(3930)$, and the $X(3960)$, observed in the $D_s^+D_s^-$ channel, is an $S$-wave $D_s^+ D_s^-$ hadronic molecule. In addition, the $J^{PC}=0^{++}$ {component in the $B^+\to D^+D^-K^+$} assigned to the $X(3915)$ in the current {\it Review of Particle Physics} has the same origin as the $X(3960)$, which has a mass around 3.94~GeV. To check the proposal, the available data in the $D\bar D$ and $D_s^+ D_s^-$ channels from both $ B$ decays and $\gamma\gamma$ fusion reaction are analyzed considering both the $D\bar D$-$D_s\bar D_s$-$D^*\bar D^*$-$D_s^*\bar D_s^*$ coupled channels with $0^{++}$ and a $2^{++}$ state introduced additionally. It is found that all the data in different processes can be simultaneously well reproduced, and the coupled-channel dynamics produce four hidden-charm scalar molecular states with masses around 3.73, 3.94, 3.99 and 4.23~GeV, respectively. The results may deepen our understanding of the spectrum of charmonia as well as of the interactions between charmed hadrons. |
1607.02152 | Mehedi Masud | Debajyoti Dutta, Raj Gandhi, Boris Kayser, Mehedi Masud, Suprabh
Prakash | Capabilities of long-baseline experiments in the presence of a sterile
neutrino | Published in JHEP, 24 pages, 12 figures, IH results added | JHEP 11(2016)122 | 10.1007/JHEP11(2016)122 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Assuming that there is a sterile neutrino, we ask what then is the ability of
long-baseline experiments to i) establish that neutrino oscillation violates
CP, ii) determine the three-neutrino mass ordering, and iii) determine which
CP-violating phase or phases are the cause of any CP violation that may be
observed. We find that the ability to establish CP violation and to determine
the mass ordering could be very substantial. However, the effects of the
sterile neutrino could be quite large, and it might prove very difficult to
determine which phase is responsible for an observed CP violation. We explain
why a sterile neutrino changes the long-baseline sensitivities to CP violation
and to the mass ordering in the ways that it does. We note that long-baseline
experiments can probe the presence of sterile neutrinos in a way that is
different from, and complementary to, the probes of short-baseline experiments.
We explore the question of how large sterile-active mixing angles need to be
before long-baseline experiments can detect their effects, or how small they
need to be before the interpretation of these experiments can safely disregard
the possible existence of sterile neutrinos.
| [
{
"created": "Thu, 7 Jul 2016 20:01:35 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Nov 2016 09:43:12 GMT",
"version": "v2"
}
] | 2016-11-30 | [
[
"Dutta",
"Debajyoti",
""
],
[
"Gandhi",
"Raj",
""
],
[
"Kayser",
"Boris",
""
],
[
"Masud",
"Mehedi",
""
],
[
"Prakash",
"Suprabh",
""
]
] | Assuming that there is a sterile neutrino, we ask what then is the ability of long-baseline experiments to i) establish that neutrino oscillation violates CP, ii) determine the three-neutrino mass ordering, and iii) determine which CP-violating phase or phases are the cause of any CP violation that may be observed. We find that the ability to establish CP violation and to determine the mass ordering could be very substantial. However, the effects of the sterile neutrino could be quite large, and it might prove very difficult to determine which phase is responsible for an observed CP violation. We explain why a sterile neutrino changes the long-baseline sensitivities to CP violation and to the mass ordering in the ways that it does. We note that long-baseline experiments can probe the presence of sterile neutrinos in a way that is different from, and complementary to, the probes of short-baseline experiments. We explore the question of how large sterile-active mixing angles need to be before long-baseline experiments can detect their effects, or how small they need to be before the interpretation of these experiments can safely disregard the possible existence of sterile neutrinos. |
1106.3209 | Igor Ivanov | I. P. Ivanov | High-energy physics with particles carrying non-zero orbital angular
momentum | 7 pages, 1 figure, talk given at the workshop "30 years of strong
interactions", Spa, Belgium, 6-8 April 2011 | null | 10.1007/s00601-011-0248-3 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Thanks to progress in optics in the past two decades, it is possible to
create photons carrying well-defined non-zero orbital angular momentum (OAM).
Boosting these photons into high-energy range preserving their OAM seems
feasible. Intermediate energy electrons with OAM have also been produced
recently. One can, therefore, view OAM as a new degree of freedom in
high-energy collisions and ask what novel insights into particles' structure
and interactions it can bring. Here we discuss generic features of scattering
processes involving particles with OAM in the initial state. We show that they
make it possible to perform a Fourier analysis of a plane wave cross section
with respect to the azimuthal angles of the initial particles, and to probe the
autocorrelation function of the amplitude, a quantity inaccessible in plane
wave collisions.
| [
{
"created": "Thu, 16 Jun 2011 12:11:00 GMT",
"version": "v1"
}
] | 2015-05-28 | [
[
"Ivanov",
"I. P.",
""
]
] | Thanks to progress in optics in the past two decades, it is possible to create photons carrying well-defined non-zero orbital angular momentum (OAM). Boosting these photons into high-energy range preserving their OAM seems feasible. Intermediate energy electrons with OAM have also been produced recently. One can, therefore, view OAM as a new degree of freedom in high-energy collisions and ask what novel insights into particles' structure and interactions it can bring. Here we discuss generic features of scattering processes involving particles with OAM in the initial state. We show that they make it possible to perform a Fourier analysis of a plane wave cross section with respect to the azimuthal angles of the initial particles, and to probe the autocorrelation function of the amplitude, a quantity inaccessible in plane wave collisions. |
0903.3186 | Sergey Afonin | S. S. Afonin | About the possibility of five-dimensional effective theories for
low-energy QCD | 11 pages, accepted by Eur. Phys. J. C | Eur.Phys.J.C61:69-73,2009 | 10.1140/epjc/s10052-009-1008-0 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The AdS/QCD models suggest an interesting idea that the effective theory of
low-energy QCD may be formulated as a 5-dimensional field theory in the weak
coupling regime in which the fifth coordinate plays a role of inverse energy
scale. Taking the point of view that this is just an efficient parametrization
of the non-perturbative dynamics of strong interactions, we discuss on a
qualitative level an alternative possibility for a simpler 5-dimensional
parametrization of main phenomena in the low-energy QCD. We propose to
interpret the effect of chiral symmetry breaking as an effective appearance of
compactified extra dimension with the radius of the order of inverse scale of
chiral symmetry breaking. Following some heuristic arguments two dual scenarios
for the emergence of the excited light mesons are introduced: In the first
scenario, the meson resonances are interpreted as the effects of Kaluza-Klein
excitations of quarks inside mesons, in the second one, as the formation of
gluon strings wound around the compactified dimension an appropriate number of
times. Matching of these scenarios permits to express the slope of radial Regge
trajectories through the order parameters of the chiral symmetry breaking, with
the compactification radius being excluded. This example shows qualitatively
that the extra dimension may play an auxiliary role providing a short way for
deriving new relations.
| [
{
"created": "Wed, 18 Mar 2009 15:36:14 GMT",
"version": "v1"
}
] | 2009-07-22 | [
[
"Afonin",
"S. S.",
""
]
] | The AdS/QCD models suggest an interesting idea that the effective theory of low-energy QCD may be formulated as a 5-dimensional field theory in the weak coupling regime in which the fifth coordinate plays a role of inverse energy scale. Taking the point of view that this is just an efficient parametrization of the non-perturbative dynamics of strong interactions, we discuss on a qualitative level an alternative possibility for a simpler 5-dimensional parametrization of main phenomena in the low-energy QCD. We propose to interpret the effect of chiral symmetry breaking as an effective appearance of compactified extra dimension with the radius of the order of inverse scale of chiral symmetry breaking. Following some heuristic arguments two dual scenarios for the emergence of the excited light mesons are introduced: In the first scenario, the meson resonances are interpreted as the effects of Kaluza-Klein excitations of quarks inside mesons, in the second one, as the formation of gluon strings wound around the compactified dimension an appropriate number of times. Matching of these scenarios permits to express the slope of radial Regge trajectories through the order parameters of the chiral symmetry breaking, with the compactification radius being excluded. This example shows qualitatively that the extra dimension may play an auxiliary role providing a short way for deriving new relations. |
1406.6338 | Ennio Salvioni | Aleksandr Azatov, Christophe Grojean, Ayan Paul and Ennio Salvioni | Taming the off-shell Higgs boson | 30 pages, 7 figures, 3 tables; v2: small improvements in discussion,
references added, typos corrected. Version submitted to JETP for a special
issue in honor of the 60th birthday of V. Rubakov; v3: matches version
published in JETP | JETP Vol. 147 (3) (2015) | 10.1134/S1063776115030140 | CERN-PH-TH-2014-108 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the off-shell Higgs data in the process $pp\to h^{(*)} \to
Z^{(\ast)}Z^{(\ast)}\to 4\ell$, to constrain deviations of the Higgs couplings.
We point out that this channel can be used to resolve the long- and
short-distance contributions to Higgs production by gluon fusion and can thus
be complementary to $pp\to ht\bar t$ in measuring the top Yukawa coupling. Our
analysis, performed in the context of Effective Field Theory, shows that
current data do not allow one to draw any model-independent conclusions. We
study the prospects at future hadron colliders, including the high-luminosity
LHC and accelerators with higher-energy, up to 100 TeV. The available QCD
calculations and the theoretical uncertainties affecting our analysis are also
briefly discussed.
| [
{
"created": "Tue, 24 Jun 2014 19:17:09 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Jul 2014 17:12:13 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Mar 2015 17:37:46 GMT",
"version": "v3"
}
] | 2015-06-22 | [
[
"Azatov",
"Aleksandr",
""
],
[
"Grojean",
"Christophe",
""
],
[
"Paul",
"Ayan",
""
],
[
"Salvioni",
"Ennio",
""
]
] | We study the off-shell Higgs data in the process $pp\to h^{(*)} \to Z^{(\ast)}Z^{(\ast)}\to 4\ell$, to constrain deviations of the Higgs couplings. We point out that this channel can be used to resolve the long- and short-distance contributions to Higgs production by gluon fusion and can thus be complementary to $pp\to ht\bar t$ in measuring the top Yukawa coupling. Our analysis, performed in the context of Effective Field Theory, shows that current data do not allow one to draw any model-independent conclusions. We study the prospects at future hadron colliders, including the high-luminosity LHC and accelerators with higher-energy, up to 100 TeV. The available QCD calculations and the theoretical uncertainties affecting our analysis are also briefly discussed. |
hep-ph/0301245 | Ralf Rapp | R. Rapp and E.V. Shuryak | D-Meson Production from Recombination in Hadronic Collisions | 14 pages RevTeX including 10 ps-figures | Phys.Rev. D67 (2003) 074036 | 10.1103/PhysRevD.67.074036 | null | hep-ph hep-ex nucl-th | null | Nonperturbative effects in $D$-meson production in pion-nucleon and
proton-nucleon collisions are investigated within the recombination model. The
coalescence of perturbatively created charm quarks with sea- and valence-quarks
from projectile and target fragments is shown to be competitive in magnitude
with standard fragmentation calculations at both central (small $x_F$) and
forward rapidities. Corresponding flavor asymmetries for inclusive $D$-meson
production are thus mostly generated on the (light-) parton distribution level,
and turn out to be in reasonable overall agreement with available fixed-target
data. Predictions for upcoming measurements at RHIC are given.
| [
{
"created": "Tue, 28 Jan 2003 14:26:09 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Rapp",
"R.",
""
],
[
"Shuryak",
"E. V.",
""
]
] | Nonperturbative effects in $D$-meson production in pion-nucleon and proton-nucleon collisions are investigated within the recombination model. The coalescence of perturbatively created charm quarks with sea- and valence-quarks from projectile and target fragments is shown to be competitive in magnitude with standard fragmentation calculations at both central (small $x_F$) and forward rapidities. Corresponding flavor asymmetries for inclusive $D$-meson production are thus mostly generated on the (light-) parton distribution level, and turn out to be in reasonable overall agreement with available fixed-target data. Predictions for upcoming measurements at RHIC are given. |
1206.6363 | Michael Seymour | Jeffrey R. Forshaw, Michael H. Seymour, Andrzej Siodmok (University of
Manchester) | On the breaking of collinear factorization in QCD | Version 2: minor improvements for journal publication | null | 10.1007/JHEP11(2012)066 | MAN/HEP/2012/05 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the breakdown of collinear factorization for non-inclusive
observables in hadron-hadron collisions. For pure QCD processes, factorization
is violated at the three-loop level and it has a structure identical to that
encountered previously in the case of super-leading logarithms. In particular,
it is driven by the non-commutation of Coulomb/Glauber gluon exchanges with
other soft exchanges. Beyond QCD, factorization may be violated at the two-loop
level provided that the hard subprocess contains matrix element contributions
with phase differences between different colour topologies.
| [
{
"created": "Wed, 27 Jun 2012 18:51:12 GMT",
"version": "v1"
},
{
"created": "Mon, 12 Nov 2012 16:59:23 GMT",
"version": "v2"
}
] | 2015-06-05 | [
[
"Forshaw",
"Jeffrey R.",
"",
"University of\n Manchester"
],
[
"Seymour",
"Michael H.",
"",
"University of\n Manchester"
],
[
"Siodmok",
"Andrzej",
"",
"University of\n Manchester"
]
] | We investigate the breakdown of collinear factorization for non-inclusive observables in hadron-hadron collisions. For pure QCD processes, factorization is violated at the three-loop level and it has a structure identical to that encountered previously in the case of super-leading logarithms. In particular, it is driven by the non-commutation of Coulomb/Glauber gluon exchanges with other soft exchanges. Beyond QCD, factorization may be violated at the two-loop level provided that the hard subprocess contains matrix element contributions with phase differences between different colour topologies. |
2308.15843 | Etido Inyang | M. Abu-Shady, E. Omugbe and E.P. Inyang | Approximate Bound State Solutions of the Fractional Schr\"odinger
Equation under the Spin-Spin-Dependent Cornell Potential | 16 pages,2 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this work, the approximate bound state solutions of the fractional
Schr\"odinger equation under a spin-spin-dependent Cornell potential are
obtained via the convectional Nikiforov-Uvarov approach. The energy spectra are
applied to obtain the mass spectra of the heavy mesons such as bottomonium,
charmonium and bottom-charm. The masses for the singlet and triplet spin
numbers increase as the quantum numbers increase. The fractional Schr\"odinger
equation improves the mass spectra compared to the masses obtained in the
existing literature. The bottomonium masses agree with the experimental data of
the Particle Data Group where percentage errors for fractional parameters of
\b{eta}=1,{\alpha}=0.97 and \b{eta}=1,{\alpha}=0.50 were found to be 0.67% and
0.49% respectively. The respective percentage errors of 1.97% and 1.62% for
fractional parameters of \b{eta}=1,{\alpha}=0.97 and \b{eta}=1,{\alpha}=0.50
were obtained for charmonium meson. The results indicate that the potential
curves coupled with the fractional parameters account for the short-range gluon
exchange between the quark-antiquark interactions and the linear confinement
phenomena which is associated with the quantum chromo-dynamic and
phenomenological potential models in particle and high-energy physics
| [
{
"created": "Wed, 30 Aug 2023 08:28:02 GMT",
"version": "v1"
}
] | 2023-08-31 | [
[
"Abu-Shady",
"M.",
""
],
[
"Omugbe",
"E.",
""
],
[
"Inyang",
"E. P.",
""
]
] | In this work, the approximate bound state solutions of the fractional Schr\"odinger equation under a spin-spin-dependent Cornell potential are obtained via the convectional Nikiforov-Uvarov approach. The energy spectra are applied to obtain the mass spectra of the heavy mesons such as bottomonium, charmonium and bottom-charm. The masses for the singlet and triplet spin numbers increase as the quantum numbers increase. The fractional Schr\"odinger equation improves the mass spectra compared to the masses obtained in the existing literature. The bottomonium masses agree with the experimental data of the Particle Data Group where percentage errors for fractional parameters of \b{eta}=1,{\alpha}=0.97 and \b{eta}=1,{\alpha}=0.50 were found to be 0.67% and 0.49% respectively. The respective percentage errors of 1.97% and 1.62% for fractional parameters of \b{eta}=1,{\alpha}=0.97 and \b{eta}=1,{\alpha}=0.50 were obtained for charmonium meson. The results indicate that the potential curves coupled with the fractional parameters account for the short-range gluon exchange between the quark-antiquark interactions and the linear confinement phenomena which is associated with the quantum chromo-dynamic and phenomenological potential models in particle and high-energy physics |
hep-ph/0412419 | Stefan Hesselbach | A. Bartl, S. Hesselbach | Standard Model and Beyond | 20 pages, LaTeX, 7 eps figures, uses ws-procs9x6.cls, lecture given
by A. Bartl at the VII School on Non-Accelerator Astroparticle Physics,
Trieste, Italy, July 26 - August 6, 2004 | null | 10.1142/9789812701893_0001 | UWThPh-2004-43 | hep-ph | null | We first discuss the basic features of electroweak 1-loop corrections in the
Standard Model. We also give a short and elementary review on Higgs boson
searches, grand unification, supersymmetry and extra dimensions.
| [
{
"created": "Thu, 30 Dec 2004 12:25:19 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Bartl",
"A.",
""
],
[
"Hesselbach",
"S.",
""
]
] | We first discuss the basic features of electroweak 1-loop corrections in the Standard Model. We also give a short and elementary review on Higgs boson searches, grand unification, supersymmetry and extra dimensions. |
1611.06095 | Marcela Gonz\'alez | Carolina Arbel\'aez, Marcela Gonz\'alez, Sergey Kovalenko, Martin
Hirsch | QCD-improved limits from neutrinoless double beta decay | 18 pages, 13 figures | Phys. Rev. D 96, 015010 (2017) | 10.1103/PhysRevD.96.015010 | IFIC/16-83 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the impact of QCD corrections on limits derived from neutrinoless
double beta decay ($0\nu\beta\beta$). As demonstrated previously, the effect of
the color-mismatch arising from loops with gluons linking the quarks from
different color-singlet currents participating in the effective operators has a
dramatic impact on the predictions for some particular Wilson coefficients.
Here, we consider all possible contributions from heavy particle exchange, i.e.
the so-called short-range mechanism of $0\nu\beta\beta$ decay. All high-scale
models (HSM) in this class match at some scale around a $\sim$ few TeV with the
corresponding effective theory, containing a certain set of effective
dimension-9 operators. Many of these HSM receive contributions from more than
one of the basic operators and we calculate limits on these models using the
latest experimental data. We also show with one non-trivial example, how to
derive limits on more complicated models, in which many different Feynman
diagrams contribute to $0\nu\beta\beta$ decay, using our general method.
| [
{
"created": "Fri, 18 Nov 2016 14:24:41 GMT",
"version": "v1"
}
] | 2017-07-19 | [
[
"Arbeláez",
"Carolina",
""
],
[
"González",
"Marcela",
""
],
[
"Kovalenko",
"Sergey",
""
],
[
"Hirsch",
"Martin",
""
]
] | We analyze the impact of QCD corrections on limits derived from neutrinoless double beta decay ($0\nu\beta\beta$). As demonstrated previously, the effect of the color-mismatch arising from loops with gluons linking the quarks from different color-singlet currents participating in the effective operators has a dramatic impact on the predictions for some particular Wilson coefficients. Here, we consider all possible contributions from heavy particle exchange, i.e. the so-called short-range mechanism of $0\nu\beta\beta$ decay. All high-scale models (HSM) in this class match at some scale around a $\sim$ few TeV with the corresponding effective theory, containing a certain set of effective dimension-9 operators. Many of these HSM receive contributions from more than one of the basic operators and we calculate limits on these models using the latest experimental data. We also show with one non-trivial example, how to derive limits on more complicated models, in which many different Feynman diagrams contribute to $0\nu\beta\beta$ decay, using our general method. |
2201.01447 | Lawrence M. Krauss | Lawrence M. Krauss (Origins Project Foundation) | Axions, Time Varying CP Violation, and Baryogenesis | 3 pages, submitted to Phys. Rev.D, also references corrected | null | null | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | We derive two features of axion cosmology that may have cosmological
implications, whether or not axions are dark matter: For the full range of
allowed axion masses, the evolution of a cosmic axion background allows large
CP violation until temperatures as low as $\sim$ 2 GeV, and once the axion
field begins to oscillate, the cosmological axion field's relaxation to its
ground state can briefly provide a new departure from thermal equilibrium, via
time-varying CP violation. During both of these periods, the Strong CP
violating parameter $\bar\theta$ can be as large as O(1).
| [
{
"created": "Wed, 5 Jan 2022 04:38:46 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Jan 2022 23:18:40 GMT",
"version": "v2"
}
] | 2022-01-10 | [
[
"Krauss",
"Lawrence M.",
"",
"Origins Project Foundation"
]
] | We derive two features of axion cosmology that may have cosmological implications, whether or not axions are dark matter: For the full range of allowed axion masses, the evolution of a cosmic axion background allows large CP violation until temperatures as low as $\sim$ 2 GeV, and once the axion field begins to oscillate, the cosmological axion field's relaxation to its ground state can briefly provide a new departure from thermal equilibrium, via time-varying CP violation. During both of these periods, the Strong CP violating parameter $\bar\theta$ can be as large as O(1). |
hep-ph/9801372 | Yuri Dokshitzer | Yu. L. Dokshitzer | QCD, Theoretical issues | 21 page; Plenary talk at the HEP EPS Conference, Jerusalem, August
1997 | null | null | null | hep-ph | null | Today's QCD problems, prospects and achievements are reviewed.
| [
{
"created": "Wed, 21 Jan 1998 12:56:15 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dokshitzer",
"Yu. L.",
""
]
] | Today's QCD problems, prospects and achievements are reviewed. |
hep-ph/9211241 | null | A. Dolgov | Antimatter in the Universe | 17 pages + 2 figures | null | 10.1007/BF02316703 | UM-TH-92-29 | hep-ph | null | Cosmological models which predict a large amount of antimatter in the
Universe are reviewed. Observational signatures and searches for cosmic
antimatter are briefly considered. A short discussion of new long range forces
which might be associated with matter and antimatter is presented.
| [
{
"created": "Thu, 12 Nov 1992 16:05:00 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Dolgov",
"A.",
""
]
] | Cosmological models which predict a large amount of antimatter in the Universe are reviewed. Observational signatures and searches for cosmic antimatter are briefly considered. A short discussion of new long range forces which might be associated with matter and antimatter is presented. |
2102.03704 | En Wang | Le-Le Wei, Hong-Shen Li, En Wang, Ju-Jun Xie, De-Min Li, and Yu-Xiao
Li | Search for a $D \bar{D}$ bound state in the $\Lambda_b \rightarrow
\Lambda D\bar{D}$ process | 7 pages, 9 figures, comments are welcome | Phys. Rev. D 103, 114013 (2021) | 10.1103/PhysRevD.103.114013 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We have investigated the process of $\Lambda_b\to \Lambda D\bar{D}$, by
taking into account the contributions from the $s$-wave $D\bar{D}$ interaction
within the coupled-channel unitary approach, and the intermediate $\psi(3770)$
resonance. In addition to the peak of the $\psi(3770)$, an enhancement near the
$D\bar{D}$ mass threshold is found in the $D\bar{D}$ invariant mass
distributions, which should be the reflection of the $D\bar{D}$ bound state. We
would like to encourage our experimental colleagues to measure the $D\bar{D}$
invariant mass distribution of the $\Lambda_b\to \Lambda D\bar{D}$ process,
which is crucial to search for the $D\bar{D}$ bound state and to understand the
heavy-hadron heavy-hadron interactions.
| [
{
"created": "Sun, 7 Feb 2021 02:58:24 GMT",
"version": "v1"
}
] | 2021-06-16 | [
[
"Wei",
"Le-Le",
""
],
[
"Li",
"Hong-Shen",
""
],
[
"Wang",
"En",
""
],
[
"Xie",
"Ju-Jun",
""
],
[
"Li",
"De-Min",
""
],
[
"Li",
"Yu-Xiao",
""
]
] | We have investigated the process of $\Lambda_b\to \Lambda D\bar{D}$, by taking into account the contributions from the $s$-wave $D\bar{D}$ interaction within the coupled-channel unitary approach, and the intermediate $\psi(3770)$ resonance. In addition to the peak of the $\psi(3770)$, an enhancement near the $D\bar{D}$ mass threshold is found in the $D\bar{D}$ invariant mass distributions, which should be the reflection of the $D\bar{D}$ bound state. We would like to encourage our experimental colleagues to measure the $D\bar{D}$ invariant mass distribution of the $\Lambda_b\to \Lambda D\bar{D}$ process, which is crucial to search for the $D\bar{D}$ bound state and to understand the heavy-hadron heavy-hadron interactions. |
hep-ph/9505262 | Thomas Teubner | A.H. Hoang, J.H. K\"uhn and T. Teubner | Radiation of Light Fermions in Heavy Fermion Production | 11 pages, LaTex (uses epsf.sty, 4 figures appended as uuencoded ps
files). The complete paper, including figures, is also available via
anonymous ftp at ftp://ttpux2.physik.uni-karlsruhe.de/ , or via www at
http://ttpux2.physik.uni-karlsruhe.de/cgi-bin/preprints/ | Nucl.Phys. B452 (1995) 173-187 | 10.1016/0550-3213(95)00308-F | TTP95-10 | hep-ph | null | The rate for the production of a pair of massive fermions in $e^+ e^-$
annihilation plus real or virtual radiation of a pair of massless fermions is
calculated analytically. The contributions for real and virtual radiation are
displayed separately. The asymptotic behaviour close to threshold and for high
energies is given in a compact form. These approximations provide arguments for
the appropriate choice of the scale in the ${\cal O}(\alpha)$ result, such that
no large logarithms remain in the final answer.
| [
{
"created": "Tue, 9 May 1995 12:50:13 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Hoang",
"A. H.",
""
],
[
"Kühn",
"J. H.",
""
],
[
"Teubner",
"T.",
""
]
] | The rate for the production of a pair of massive fermions in $e^+ e^-$ annihilation plus real or virtual radiation of a pair of massless fermions is calculated analytically. The contributions for real and virtual radiation are displayed separately. The asymptotic behaviour close to threshold and for high energies is given in a compact form. These approximations provide arguments for the appropriate choice of the scale in the ${\cal O}(\alpha)$ result, such that no large logarithms remain in the final answer. |
2404.15988 | Glauber Carvalho Dorsch | Bruno Berganholi, Gl\'auber C. Dorsch, Beatriz M. D. Sena and Giovanna
F. do Valle | Symmetries in particle physics: from nuclear isospin to the quark model | 12 figures, 24 pages | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a concise pedagogic introduction to group representation theory
motivated by the historical developments surrounding the advent of the
Eightfold Way. Abstract definitions of groups and representations are avoided
in favour of the physical intuition of symmetries of the nuclear interaction.
The concept of nuclear isospin is used as a physical motivation to introduce
SU(2) and discuss the main techniques of representation theory. The discovery
of strange particles motivates extending the symmetry group to SU(3), at first
in the context of the Sakata model. We highlight the successes in fitting
mesons in the SU(3) octet, discuss the drawbacks of the Sakata model for
baryonic classifications, and how the Eightfold Way finally led to the quark
model. This approach has two major advantages: (i) the main concepts of the
theory of Lie groups are introduced and discussed without ever losing touch
with its applications in particle physics; (ii) it allows the beginner to study
group theory while also becoming acquainted with the historical developments of
particle physics that led to the concept of quarks. In particular, in this
pedagogical path the quarks appear as yet another class of particles predicted
from symmetry principles, rather than being introduced ad hoc for postulating
an SU(3) symmetry, as usually done in the literature.
| [
{
"created": "Wed, 24 Apr 2024 17:02:15 GMT",
"version": "v1"
}
] | 2024-04-25 | [
[
"Berganholi",
"Bruno",
""
],
[
"Dorsch",
"Gláuber C.",
""
],
[
"Sena",
"Beatriz M. D.",
""
],
[
"Valle",
"Giovanna F. do",
""
]
] | We present a concise pedagogic introduction to group representation theory motivated by the historical developments surrounding the advent of the Eightfold Way. Abstract definitions of groups and representations are avoided in favour of the physical intuition of symmetries of the nuclear interaction. The concept of nuclear isospin is used as a physical motivation to introduce SU(2) and discuss the main techniques of representation theory. The discovery of strange particles motivates extending the symmetry group to SU(3), at first in the context of the Sakata model. We highlight the successes in fitting mesons in the SU(3) octet, discuss the drawbacks of the Sakata model for baryonic classifications, and how the Eightfold Way finally led to the quark model. This approach has two major advantages: (i) the main concepts of the theory of Lie groups are introduced and discussed without ever losing touch with its applications in particle physics; (ii) it allows the beginner to study group theory while also becoming acquainted with the historical developments of particle physics that led to the concept of quarks. In particular, in this pedagogical path the quarks appear as yet another class of particles predicted from symmetry principles, rather than being introduced ad hoc for postulating an SU(3) symmetry, as usually done in the literature. |
2009.01684 | Shao-Feng Ge | Shao-Feng Ge and Pedro Pasquini | Parity Violation and Chiral Oscillation of Cosmological Relic Neutrinos | 5 pages, 1 figure | null | 10.1016/j.physletb.2020.135961 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The conventional derivation of neutrino oscillation treats neutrino mass
eigenstate as plane wave with an overall evolution phase. Nevertheless, due to
the intrinsic parity-violating nature of weak interactions, only the
left-chiral neutrino can be produced as initial condition. On the other hand,
the neutrino mass term connects the left-chiral component to the right-chiral
one and unavoidably leads to generation of the later through oscillation. This
chiral oscillation has significant consequences on the detection of the
cosmological relic neutrinos. The event rate is reduced by a factor of 2 than
the conventional prediction.
| [
{
"created": "Thu, 3 Sep 2020 14:09:42 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Sep 2020 00:43:03 GMT",
"version": "v2"
}
] | 2020-11-25 | [
[
"Ge",
"Shao-Feng",
""
],
[
"Pasquini",
"Pedro",
""
]
] | The conventional derivation of neutrino oscillation treats neutrino mass eigenstate as plane wave with an overall evolution phase. Nevertheless, due to the intrinsic parity-violating nature of weak interactions, only the left-chiral neutrino can be produced as initial condition. On the other hand, the neutrino mass term connects the left-chiral component to the right-chiral one and unavoidably leads to generation of the later through oscillation. This chiral oscillation has significant consequences on the detection of the cosmological relic neutrinos. The event rate is reduced by a factor of 2 than the conventional prediction. |
hep-ph/0006023 | Wit | K. Fialkowski and R. Wit | Are charge fluctuations a good signal for QGP? | 3 pages, 1 figure | null | null | null | hep-ph | null | A recent proposal to study charge fluctuations as a possible signal of
quark-gluon plasma is discussed. It is shown that the "pion gas model"
considered as the reference sample is unrealistic and the expected signal from
plasma may be difficult to distinguish from that coming from "standard
collisions".
| [
{
"created": "Fri, 2 Jun 2000 09:50:08 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Fialkowski",
"K.",
""
],
[
"Wit",
"R.",
""
]
] | A recent proposal to study charge fluctuations as a possible signal of quark-gluon plasma is discussed. It is shown that the "pion gas model" considered as the reference sample is unrealistic and the expected signal from plasma may be difficult to distinguish from that coming from "standard collisions". |
hep-ph/0201186 | Jan Kalinowski | Wojciech Krolikowski | Neutrino bimaximal mixing and unitary deformation of fermion
universality | 9 pages, latex, no figures | null | null | IFT-02/02 | hep-ph | null | An effective texture is presented for six Majorana neutrinos, three active
and three (conventional) sterile, based on a 6x6 mass matrix whose 3x3 Dirac
component (i.e., active--sterile component) is conjectured to get a
hierarchical fermion universal form, similar to the previously constructed 3x3
mass matrices for charged leptons as well as for up and down quarks. However,
for neutrinos this form becomes unitarily deformed by the action of bimaximal
mixing, specific in their case. The 3x3 lefthanded and righthanded components
(i.e., active-active and sterile-sterile components) of the 6x6 mass matrix are
diagonal with degenerate entries of opposite sign. They dominate over the 3x3
Dirac component. In such a texture the neutrino masses are $ m_1 = -m_4 \simeq
m_2 = -m_5 \simeq m_3 = -m_6 $ with the mass-squared differences $\Delta
m^2_{21} \ll \Delta m^2_{32} \simeq \Delta m^2_{31}$ and $\Delta m^2_{41} =
\Delta m^2_{52} = \Delta m^2_{63} = 0$. The last equality implies in our
texture the absence of oscillations for three (conventional) sterile neutrinos.
Thus, these neutrinos are here effectively decoupled, what is realized
evidently in another way than through the popular seesaw mechanism. There
remain the oscillations of three active neutrinos, getting the form as for
bimaximal mixing, but with the mass spectrum following from our texture.
| [
{
"created": "Mon, 21 Jan 2002 10:18:20 GMT",
"version": "v1"
}
] | 2016-09-06 | [
[
"Krolikowski",
"Wojciech",
""
]
] | An effective texture is presented for six Majorana neutrinos, three active and three (conventional) sterile, based on a 6x6 mass matrix whose 3x3 Dirac component (i.e., active--sterile component) is conjectured to get a hierarchical fermion universal form, similar to the previously constructed 3x3 mass matrices for charged leptons as well as for up and down quarks. However, for neutrinos this form becomes unitarily deformed by the action of bimaximal mixing, specific in their case. The 3x3 lefthanded and righthanded components (i.e., active-active and sterile-sterile components) of the 6x6 mass matrix are diagonal with degenerate entries of opposite sign. They dominate over the 3x3 Dirac component. In such a texture the neutrino masses are $ m_1 = -m_4 \simeq m_2 = -m_5 \simeq m_3 = -m_6 $ with the mass-squared differences $\Delta m^2_{21} \ll \Delta m^2_{32} \simeq \Delta m^2_{31}$ and $\Delta m^2_{41} = \Delta m^2_{52} = \Delta m^2_{63} = 0$. The last equality implies in our texture the absence of oscillations for three (conventional) sterile neutrinos. Thus, these neutrinos are here effectively decoupled, what is realized evidently in another way than through the popular seesaw mechanism. There remain the oscillations of three active neutrinos, getting the form as for bimaximal mixing, but with the mass spectrum following from our texture. |
hep-ph/0302268 | V. A. Yerokhin | V. A. Yerokhin, P. Indelicato, and V. M. Shabaev | Two-loop self-energy correction in high-Z hydrogen-like ions | RevTeX, 5 figures, 1 table | Phys.Rev.Lett. 91 (2003) 073001 | 10.1103/PhysRevLett.91.073001 | null | hep-ph | null | A complete evaluation of the two-loop self-energy diagrams to all orders in
Z\alpha is presented for the ground state of H-like ions with Z\ge 40.
| [
{
"created": "Fri, 28 Feb 2003 08:24:29 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Yerokhin",
"V. A.",
""
],
[
"Indelicato",
"P.",
""
],
[
"Shabaev",
"V. M.",
""
]
] | A complete evaluation of the two-loop self-energy diagrams to all orders in Z\alpha is presented for the ground state of H-like ions with Z\ge 40. |
hep-ph/0007331 | Liliana Micu | L. Micu (NIPNE-HH, Bucharest, Romania) | A Lorentz covariant approach to the bound state problem | 7 pages, Latex, no figures | null | null | null | hep-ph | null | The relativistic equivalent of the Schr\"odinger equation for a two particle
bound state having the total angular momentum $S$ is written in the form of a
Lorentz covariant set of equations (p_1^mu+p_2^mu+Omega^mu)Psi(p_1,p_2;P)
chi_S(\vec{p}_1,\vec{p}_2)=P^mu Psi(p_1,p_2;P) chi_S(\vec{p}_1,\vec{p}_2) where
the operators Omega^mu are the components of a 4-vector quasipotential. The
solution of this set is a stationary function representing the distribution of
spins and internal momenta in a reference frame where the momentum of the bound
system is P^\mu.
The contribution of the operators Omega^mu to the bound state momentum is
assumed to be the 4-momentum of a vacuum-like effective field entering the
bound system as an independent component. It is shown that a state made of free
quarks and of the effective field has definite mass and can be normalized like
a single particle state.
The generalization to the case of three or more particles is immediate.
| [
{
"created": "Fri, 28 Jul 2000 10:05:15 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Micu",
"L.",
"",
"NIPNE-HH, Bucharest, Romania"
]
] | The relativistic equivalent of the Schr\"odinger equation for a two particle bound state having the total angular momentum $S$ is written in the form of a Lorentz covariant set of equations (p_1^mu+p_2^mu+Omega^mu)Psi(p_1,p_2;P) chi_S(\vec{p}_1,\vec{p}_2)=P^mu Psi(p_1,p_2;P) chi_S(\vec{p}_1,\vec{p}_2) where the operators Omega^mu are the components of a 4-vector quasipotential. The solution of this set is a stationary function representing the distribution of spins and internal momenta in a reference frame where the momentum of the bound system is P^\mu. The contribution of the operators Omega^mu to the bound state momentum is assumed to be the 4-momentum of a vacuum-like effective field entering the bound system as an independent component. It is shown that a state made of free quarks and of the effective field has definite mass and can be normalized like a single particle state. The generalization to the case of three or more particles is immediate. |
1501.06750 | Michael C. Birse | Mohammad H. Alhakami and Michael C. Birse (University of Manchester) | Power counting for three-body decays of a near-threshold state | 5 pages, 1 figure; more discussion of pion exchange added | Phys. Rev. D 91, 054019 (2015) | 10.1103/PhysRevD.91.054019 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new power counting for the effective field theory describing a
near-threshold state with unstable constituents, such as the X(3872) meson. In
this counting, the momenta of the heavy particles, the pion mass and the
excitation energy of the unstable constituent -- the D* in the case of the X --
are treated as small scales, of order Q. The difference, delta, between the
excitation energy of the D* and the pion mass is smaller than either by a
factor ~20. We therefore assign delta an order Q^2 in our counting. This
provides a consistent framework for a double expansion in both delta/m_pi and
the ratio of m_pi to the high-energy scales in this system. It ensures that
amplitudes have the correct behaviour at the three-body threshold. It allows us
to derive, within an effective theory, various results which have previously
been obtained using physically-motivated approximations.
| [
{
"created": "Tue, 27 Jan 2015 11:45:27 GMT",
"version": "v1"
},
{
"created": "Mon, 23 Feb 2015 08:47:55 GMT",
"version": "v2"
}
] | 2015-03-18 | [
[
"Alhakami",
"Mohammad H.",
"",
"University of Manchester"
],
[
"Birse",
"Michael C.",
"",
"University of Manchester"
]
] | We propose a new power counting for the effective field theory describing a near-threshold state with unstable constituents, such as the X(3872) meson. In this counting, the momenta of the heavy particles, the pion mass and the excitation energy of the unstable constituent -- the D* in the case of the X -- are treated as small scales, of order Q. The difference, delta, between the excitation energy of the D* and the pion mass is smaller than either by a factor ~20. We therefore assign delta an order Q^2 in our counting. This provides a consistent framework for a double expansion in both delta/m_pi and the ratio of m_pi to the high-energy scales in this system. It ensures that amplitudes have the correct behaviour at the three-body threshold. It allows us to derive, within an effective theory, various results which have previously been obtained using physically-motivated approximations. |
1611.09094 | Stefano Di Chiara | Stefano Di Chiara, Matti Heikinheimo, Kimmo Tuominen | Vector resonances at LHC Run II in composite 2HDM | 15 pages, 5 figures: eqs.4,7,13-17 and fig.4 added, text revised and
extended; version to appear on JHEP | null | 10.1007/JHEP03(2017)009 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a model where the electroweak symmetry breaking is driven by
strong dynamics, resulting in an electroweak doublet scalar condensate, and
transmitted to the standard model matter fields via another electroweak doublet
scalar. At low energies the effective theory therefore shares features with a
type-I two Higgs doublet model. However, important differences arise due to the
rich composite spectrum expected to contain new vector resonances accessible at
the LHC. We carry out a systematic analysis of the vector resonance signals at
LHC and find that the model remains viable, but will be tightly constrained by
direct searches as the projected integrated luminosity, around 200 fb$^{-1}$,
of the current run becomes available.
| [
{
"created": "Mon, 28 Nov 2016 12:24:06 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Mar 2017 17:03:45 GMT",
"version": "v2"
}
] | 2017-04-05 | [
[
"Di Chiara",
"Stefano",
""
],
[
"Heikinheimo",
"Matti",
""
],
[
"Tuominen",
"Kimmo",
""
]
] | We consider a model where the electroweak symmetry breaking is driven by strong dynamics, resulting in an electroweak doublet scalar condensate, and transmitted to the standard model matter fields via another electroweak doublet scalar. At low energies the effective theory therefore shares features with a type-I two Higgs doublet model. However, important differences arise due to the rich composite spectrum expected to contain new vector resonances accessible at the LHC. We carry out a systematic analysis of the vector resonance signals at LHC and find that the model remains viable, but will be tightly constrained by direct searches as the projected integrated luminosity, around 200 fb$^{-1}$, of the current run becomes available. |
2012.09176 | Javier Fernandez Acevedo | Javier F. Acevedo, Joseph Bramante, Alan Goodman, Joachim Kopp and
Toby Opferkuch | Dark Matter, Destroyer of Worlds: Neutrino, Thermal, and Existential
Signatures from Black Holes in the Sun and Earth | 40 pages, 12 figures, JCAP version | null | 10.1088/1475-7516/2021/04/026 | CERN-TH-2020-209, MITP/20-081 | hep-ph astro-ph.HE hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Dark matter can be captured by celestial objects and accumulate at their
centers, forming a core of dark matter that can collapse to a small black hole,
provided that the annihilation rate is small or zero. If the nascent black hole
is big enough, it will grow to consume the star or planet. We calculate the
rate of dark matter accumulation in the Sun and Earth, and use their continued
existence to place novel constraints on high mass asymmetric dark matter
interactions. We also identify and detail less destructive signatures: a
newly-formed black hole can be small enough to evaporate via Hawking radiation,
resulting in an anomalous heat flow emanating from Earth, or in a flux of
high-energy neutrinos from the Sun observable at IceCube. The latter signature
is entirely new, and we find that it may cover large regions of parameter space
that are not probed by any other method.
| [
{
"created": "Wed, 16 Dec 2020 19:00:01 GMT",
"version": "v1"
},
{
"created": "Tue, 11 May 2021 19:04:03 GMT",
"version": "v2"
}
] | 2021-05-13 | [
[
"Acevedo",
"Javier F.",
""
],
[
"Bramante",
"Joseph",
""
],
[
"Goodman",
"Alan",
""
],
[
"Kopp",
"Joachim",
""
],
[
"Opferkuch",
"Toby",
""
]
] | Dark matter can be captured by celestial objects and accumulate at their centers, forming a core of dark matter that can collapse to a small black hole, provided that the annihilation rate is small or zero. If the nascent black hole is big enough, it will grow to consume the star or planet. We calculate the rate of dark matter accumulation in the Sun and Earth, and use their continued existence to place novel constraints on high mass asymmetric dark matter interactions. We also identify and detail less destructive signatures: a newly-formed black hole can be small enough to evaporate via Hawking radiation, resulting in an anomalous heat flow emanating from Earth, or in a flux of high-energy neutrinos from the Sun observable at IceCube. The latter signature is entirely new, and we find that it may cover large regions of parameter space that are not probed by any other method. |
hep-ph/9903236 | Stephen Wong | S.M.H. Wong | Colour Octet Contribution in Exclusive P-Wave Charmonium Decay into
Octet and Decuplet Baryons | 58 pages, 17 embedded PS figures, corrected typos, added appendix of
numerical parameters, version to appear in Eur. Phys. J. C | Eur.Phys.J.C14:643-671,2000 | 10.1007/s100520000376 | NUC-MINN-98/12-T | hep-ph hep-ex | null | In the last years, the need of the colour octet state in inclusive P-wave
charmonium decay has been firmly established. However, the implications of this
in the corresponding exclusive reactions have not been fully recognized. We
argue for the necessity of the colour octet in P- and higher-wave quarkonium
decay. Using a set of phenomenologically constructed baryon wavefunctions, we
consider the Chi_J decay into octet and decuplet baryon-antibaryon pair. By
doing so, we subject the wavefunctions to a test of applicability. We show that
the colour singlet component alone is insufficient to account for experimental
measurements and only by including the colour octet contribution can the
partial theoretical decay widths be brought into range of the data. By the
present and earlier applications of the set of wavefunctions, they show
themselves to be reasonable model wavefunctions at around the scale Q^2 \sim
10-20 GeV^2.
| [
{
"created": "Wed, 3 Mar 1999 00:14:12 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Feb 2000 17:32:17 GMT",
"version": "v2"
}
] | 2009-01-07 | [
[
"Wong",
"S. M. H.",
""
]
] | In the last years, the need of the colour octet state in inclusive P-wave charmonium decay has been firmly established. However, the implications of this in the corresponding exclusive reactions have not been fully recognized. We argue for the necessity of the colour octet in P- and higher-wave quarkonium decay. Using a set of phenomenologically constructed baryon wavefunctions, we consider the Chi_J decay into octet and decuplet baryon-antibaryon pair. By doing so, we subject the wavefunctions to a test of applicability. We show that the colour singlet component alone is insufficient to account for experimental measurements and only by including the colour octet contribution can the partial theoretical decay widths be brought into range of the data. By the present and earlier applications of the set of wavefunctions, they show themselves to be reasonable model wavefunctions at around the scale Q^2 \sim 10-20 GeV^2. |
hep-ph/9508371 | Victor Pervushin | V.N. Pervushin, G. Roepke, M.K. Volkov, D. Blaschke, H.-P. Pavel and
A. Litvin | Bogoliubov condensation of gluons and spontaneous gauge symmetry
breaking in QCD | 16 pages, LaTex, revised version | null | null | MPG-VT-UR 60/95 | hep-ph | null | The problem of the gluonic quasiparticle excitations in QCD is considered
under the aspect of the condensation of gluon pairs in the ''squeezed'' vacuum.
The present approach is a field theoretical generalization of the Bogoliubov
model which successfully reproduced the Landau spectrum in the microscopic
theory of superfluidity. We construct a gauge invariant QCD Hamiltonian by
formally solving the Gauss equation such that the physical variables are
separated by a non-Abelian projection operator, instead of fixing a gauge. By
using Dirac quantization we show that the Bogoliubov condensation of gluon
pairs destroys this projection operator, and the spontaneous appearance of a
gluon mass is accompanied by a longitudinal component for the gluon field in
correspondence with the relativistic covariance. Gauge symmetry is broken
spontaneously since the gauge invariance of the Hamiltonian is not shared by
the vacuum. The squeezed vacuum in the present model is characterized by one
free parameter related to the contraction of a pair of zero momentum gluon
fields which is fixed from the difference of the $\eta'$ and the $\eta$ - meson
masses ($ U(1)$-problem) and results in a value for the gluon condensate which
is in good agreement with the value obtained by Shifman, Vainshtein and
Zakharov.
| [
{
"created": "Fri, 25 Aug 1995 14:46:52 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Dec 1995 17:34:36 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Pervushin",
"V. N.",
""
],
[
"Roepke",
"G.",
""
],
[
"Volkov",
"M. K.",
""
],
[
"Blaschke",
"D.",
""
],
[
"Pavel",
"H. -P.",
""
],
[
"Litvin",
"A.",
""
]
] | The problem of the gluonic quasiparticle excitations in QCD is considered under the aspect of the condensation of gluon pairs in the ''squeezed'' vacuum. The present approach is a field theoretical generalization of the Bogoliubov model which successfully reproduced the Landau spectrum in the microscopic theory of superfluidity. We construct a gauge invariant QCD Hamiltonian by formally solving the Gauss equation such that the physical variables are separated by a non-Abelian projection operator, instead of fixing a gauge. By using Dirac quantization we show that the Bogoliubov condensation of gluon pairs destroys this projection operator, and the spontaneous appearance of a gluon mass is accompanied by a longitudinal component for the gluon field in correspondence with the relativistic covariance. Gauge symmetry is broken spontaneously since the gauge invariance of the Hamiltonian is not shared by the vacuum. The squeezed vacuum in the present model is characterized by one free parameter related to the contraction of a pair of zero momentum gluon fields which is fixed from the difference of the $\eta'$ and the $\eta$ - meson masses ($ U(1)$-problem) and results in a value for the gluon condensate which is in good agreement with the value obtained by Shifman, Vainshtein and Zakharov. |
2204.09974 | Matteo Rinaldi | M. Rinaldi, F. A. Ceccopieri and V. Vento | The pion in the graviton soft-wall model: phenomenological applications | 23 pages, 15 figures. Acceptet version in THE EUROPEAN PHYSICAL
JOURNAL C. References added | null | 10.1140/epjc/s10052-022-10538-z | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The holographic graviton soft-wall model, introduced to describe the spectrum
of scalar and tensor glueballs, is improved to incorporate the realization of
chiral-symmetry as in QCD. Such a goal is achieved by including the
longitudinal dynamics of QCD into the scheme. Using the relation between
AdS/QCD and Light-Front dynamics, we construct the appropriate wave function
for the pion which is used to calculate several pion observables. The
comparison of our results with phenomenology is remarkably successful.
| [
{
"created": "Thu, 21 Apr 2022 08:57:43 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Jun 2022 15:07:55 GMT",
"version": "v2"
}
] | 2022-08-10 | [
[
"Rinaldi",
"M.",
""
],
[
"Ceccopieri",
"F. A.",
""
],
[
"Vento",
"V.",
""
]
] | The holographic graviton soft-wall model, introduced to describe the spectrum of scalar and tensor glueballs, is improved to incorporate the realization of chiral-symmetry as in QCD. Such a goal is achieved by including the longitudinal dynamics of QCD into the scheme. Using the relation between AdS/QCD and Light-Front dynamics, we construct the appropriate wave function for the pion which is used to calculate several pion observables. The comparison of our results with phenomenology is remarkably successful. |
hep-ph/0306198 | Valery V. Nesvizhevsky | V. V. Nesvizhevsky (1), H. G. Boerner (1), A. M. Gagarsky (2), A. K.
Petoukhov (1 and 2), G. A. Petrov (2), H. Abele (3), S. Baessler (3 and 7),
G. Divkovic (3), F. J. Ruess (3), Th. Stoeferle (3), A. Westphal (3), A. V.
Strelkov (4), K. V. Protasov (5), A. Yu. Voronin (6, 5) ((1) Institute
Laue-Langevin, Grenoble, France, (2) Peterburg Nuclear Physics Institute,
Gatchina, Russia, (3) University of Heidelberg, Germany, (4) Joint Institute
for Nuclear Research, Dubna, Russia, (5) Institut Sciences Nucleare,
Grenoble, France, (6) FIAN, Moscow, Russia) | Measurement of quantum states of neutrons in the Earth's gravitational
field | null | Phys.Rev. D67 (2003) 102002 | 10.1103/PhysRevD.67.102002 | null | hep-ph | null | The lowest stationary quantum state of neutrons in the Earth's gravitational
field is identified in the measurement of neutron transmission between a
horizontal mirror on the bottom and an absorber on top. Such an assembly is not
transparent for neutrons if the absorber height is smaller than the "height" of
the lowest quantum state.
| [
{
"created": "Sat, 21 Jun 2003 19:40:46 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Nesvizhevsky",
"V. V.",
"",
"1 and 2"
],
[
"Boerner",
"H. G.",
"",
"1 and 2"
],
[
"Gagarsky",
"A. M.",
"",
"1 and 2"
],
[
"Petoukhov",
"A. K.",
"",
"1 and 2"
],
[
"Petrov",
"G. A.",
"",
"3 and 7"
],
[
"Abele",
"H.",
"",
"3 and 7"
],
[
"Baessler",
"S.",
"",
"3 and 7"
],
[
"Divkovic",
"G.",
""
],
[
"Ruess",
"F. J.",
""
],
[
"Stoeferle",
"Th.",
""
],
[
"Westphal",
"A.",
""
],
[
"Strelkov",
"A. V.",
""
],
[
"Protasov",
"K. V.",
""
],
[
"Voronin",
"A. Yu.",
""
]
] | The lowest stationary quantum state of neutrons in the Earth's gravitational field is identified in the measurement of neutron transmission between a horizontal mirror on the bottom and an absorber on top. Such an assembly is not transparent for neutrons if the absorber height is smaller than the "height" of the lowest quantum state. |
1502.06158 | Samoil Bilenky M. | S. M. Bilenky | Some comments on high precision study of neutrino oscillations | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I discuss some problems connected with the high precision study of neutrino
oscillations. In the general case of $n$-neutrino mixing I derive a convenient
expression for transition probability in which only independent terms (and
mass-squared differences) enter. For three-neutrino mixing I discuss a problem
of a definition of a large (atmospheric) neutrino mass-squared difference. I
comment also possibilities to reveal the character of neutrino mass spectrum in
future reactor neutrino experiments.
| [
{
"created": "Sun, 22 Feb 2015 00:51:04 GMT",
"version": "v1"
}
] | 2015-02-24 | [
[
"Bilenky",
"S. M.",
""
]
] | I discuss some problems connected with the high precision study of neutrino oscillations. In the general case of $n$-neutrino mixing I derive a convenient expression for transition probability in which only independent terms (and mass-squared differences) enter. For three-neutrino mixing I discuss a problem of a definition of a large (atmospheric) neutrino mass-squared difference. I comment also possibilities to reveal the character of neutrino mass spectrum in future reactor neutrino experiments. |
0905.1148 | Pran Nath | Daniel Feldman, Zuowei Liu, and Pran Nath | Gluino NLSP, Dark Matter via Gluino Coannihilation, and LHC Signatures | 33 pages, 8 figures, accepted for publication in Physical Review D | Phys.Rev.D80:015007,2009 | 10.1103/PhysRevD.80.015007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The possibility that the gluino is the next to the lightest supersymmetric
particle (NLSP) is discussed and it is shown that this situation arises in
nonuniversal SUGRA models within a significant part of the parameter space
compatible with all known experimental bounds. It is then shown that the gluino
NLSP (GNLSP) models lead to a compressed sfermion spectrum with the sleptons
often heavier than the squarks at least for the first two generations. The
relic density here is governed by gluino coannihilation which is responsible
for a relatively small mass splitting between the gluino and the neutralino
masses. Thus the GNLSP class of models is very predictive first because the
SUSY production cross sections at the LHC are dominated by gluino production
and second because the gluino production itself proceeds dominantly through a
single channel which allows for a direct determination of the gluino mass and
an indirect determination of the neutralino mass due to a linear relation
between these two masses which is highly constrained by coannihilation. A
detailed analysis of these models shows that the jet production and tagged
b-jets from the gluino production can be discriminated from the standard model
background with appropriate cuts. It is found that the GNLSP models can be
tested with just 10 fb$^{-1}$ of integrated luminosity and may therefore be
checked with low luminosity runs in the first data at the LHC. Thus if a GNLSP
model is realized, the LHC will turn into a gluino factory through a profuse
production of gluinos with typically only a small fraction $\lesssim 5%$ of
total SUSY events arising from other production modes over the allowed GNLSP
model parameter space.
| [
{
"created": "Fri, 8 May 2009 16:47:47 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Jul 2009 18:19:47 GMT",
"version": "v2"
}
] | 2014-11-18 | [
[
"Feldman",
"Daniel",
""
],
[
"Liu",
"Zuowei",
""
],
[
"Nath",
"Pran",
""
]
] | The possibility that the gluino is the next to the lightest supersymmetric particle (NLSP) is discussed and it is shown that this situation arises in nonuniversal SUGRA models within a significant part of the parameter space compatible with all known experimental bounds. It is then shown that the gluino NLSP (GNLSP) models lead to a compressed sfermion spectrum with the sleptons often heavier than the squarks at least for the first two generations. The relic density here is governed by gluino coannihilation which is responsible for a relatively small mass splitting between the gluino and the neutralino masses. Thus the GNLSP class of models is very predictive first because the SUSY production cross sections at the LHC are dominated by gluino production and second because the gluino production itself proceeds dominantly through a single channel which allows for a direct determination of the gluino mass and an indirect determination of the neutralino mass due to a linear relation between these two masses which is highly constrained by coannihilation. A detailed analysis of these models shows that the jet production and tagged b-jets from the gluino production can be discriminated from the standard model background with appropriate cuts. It is found that the GNLSP models can be tested with just 10 fb$^{-1}$ of integrated luminosity and may therefore be checked with low luminosity runs in the first data at the LHC. Thus if a GNLSP model is realized, the LHC will turn into a gluino factory through a profuse production of gluinos with typically only a small fraction $\lesssim 5%$ of total SUSY events arising from other production modes over the allowed GNLSP model parameter space. |
hep-ph/9411236 | Stephen S. Pinsky | Stephen Pinsky | Topology and Confinement In Light-Front QCD | 6 pages,Latex | null | null | OHSTPY-HEP-T-94-019 | hep-ph | null | In 1+1 dimensional compact QCD the zero modes of $A^+$ give the theory a non-
trivial topological structure. We examine the effects of these topological
structures on the confining infrared structure of the theory. We show that the
ground state wavefunction of the topological excitation smears the infrared
behavior sufficiently to eliminate confinement for some matter currents. We
review the work of Franke et.al. which shows that the zero modes of$A^+$ in
$QCD_{3+1}$ give rise to instantons. The relation of zero modes of$A^+$.Invited
talk at the workshop on "Theory of Hadrons ond Light-Front QCD" at Polona
Zgorzelisko, Poland August 15-25 1994
| [
{
"created": "Mon, 7 Nov 1994 20:13:14 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Pinsky",
"Stephen",
""
]
] | In 1+1 dimensional compact QCD the zero modes of $A^+$ give the theory a non- trivial topological structure. We examine the effects of these topological structures on the confining infrared structure of the theory. We show that the ground state wavefunction of the topological excitation smears the infrared behavior sufficiently to eliminate confinement for some matter currents. We review the work of Franke et.al. which shows that the zero modes of$A^+$ in $QCD_{3+1}$ give rise to instantons. The relation of zero modes of$A^+$.Invited talk at the workshop on "Theory of Hadrons ond Light-Front QCD" at Polona Zgorzelisko, Poland August 15-25 1994 |
1301.1384 | Aleksandrs Aleksejevs | A. Aleksejevs, S. Barkanova, E. Kuraev, V. Zykunov | NLO and NNLO EWC for PV Moller Scattering | ICHEP2012 proceedings, 6 pages | null | null | null | hep-ph | http://creativecommons.org/licenses/by-nc-sa/3.0/ | High-precision electroweak experiments such as parity-violating Moller
scattering can provide indirect access to physics at multi-TeV scales and play
an important complementary role to the LHC research program. However, before
physics of interest can be extracted from experimental data, electroweak
radiative corrections, which can significantly reduce the cross-section
asymmetry, must be calculated with an unprecedented completeness and accuracy.
Although the two-loop corrections are strongly suppressed relative to the
one-loop corrections, they can no longer be dismissed for the upcoming
precision experiments. We evaluate a full gauge-invariant set of one-loop and
several types of two-loop radiative corrections for the parity-violating
electron-electron scattering asymmetry by combining two distinct but
mutually-reinforcing techniques: semiautomatic, precise, with FeynArts and
FormCalc as base languages, and by hand, with some approximations. For 11 GeV
relevant for the ultra-precise MOLLER experiment planned at JLab, the results
obtained by two approaches are in excellent agreement, which gives us assurance
that our calculations are error-free.
| [
{
"created": "Tue, 8 Jan 2013 02:27:30 GMT",
"version": "v1"
}
] | 2013-01-09 | [
[
"Aleksejevs",
"A.",
""
],
[
"Barkanova",
"S.",
""
],
[
"Kuraev",
"E.",
""
],
[
"Zykunov",
"V.",
""
]
] | High-precision electroweak experiments such as parity-violating Moller scattering can provide indirect access to physics at multi-TeV scales and play an important complementary role to the LHC research program. However, before physics of interest can be extracted from experimental data, electroweak radiative corrections, which can significantly reduce the cross-section asymmetry, must be calculated with an unprecedented completeness and accuracy. Although the two-loop corrections are strongly suppressed relative to the one-loop corrections, they can no longer be dismissed for the upcoming precision experiments. We evaluate a full gauge-invariant set of one-loop and several types of two-loop radiative corrections for the parity-violating electron-electron scattering asymmetry by combining two distinct but mutually-reinforcing techniques: semiautomatic, precise, with FeynArts and FormCalc as base languages, and by hand, with some approximations. For 11 GeV relevant for the ultra-precise MOLLER experiment planned at JLab, the results obtained by two approaches are in excellent agreement, which gives us assurance that our calculations are error-free. |
hep-ph/9708401 | null | Daniel F. Litim | On the Finite Temperature Phase Transition of Scalar QED | Talk given at the conf. Strong and Electroweak Matter '97, Eger,
Hungary, 21-25 May 1997, to be published in the proceedings, 6 pages, 4 ps
figures | null | null | Imperial/TP/96-97/58 | hep-ph | null | We analyse the finite temperature phase transition of scalar QED in euclidean
spacetime. Analytical solutions of approximations to a Wilsonian
renormalisation group equation are discussed. Special emphasis is put on the
discussion of the $3d$ running of the Abelian charge and its effects on
thermodynamical quantities. An upper bound for the range of first-order phase
transitions is given. Our results are compared to those of resummed
perturbation theory.
| [
{
"created": "Tue, 19 Aug 1997 14:42:13 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Litim",
"Daniel F.",
""
]
] | We analyse the finite temperature phase transition of scalar QED in euclidean spacetime. Analytical solutions of approximations to a Wilsonian renormalisation group equation are discussed. Special emphasis is put on the discussion of the $3d$ running of the Abelian charge and its effects on thermodynamical quantities. An upper bound for the range of first-order phase transitions is given. Our results are compared to those of resummed perturbation theory. |
hep-ph/9211307 | null | K. Enqvist and H. Uibo | Cosmological Neutrino Mass Limit Revisited | 11 pages (2 figures available on request), NORDITA-92/87 P | Phys.Lett.B301:376-381,1993 | 10.1016/0370-2693(93)91166-K | null | hep-ph | null | We consider the equilibration of the 'wrong--helicity' Dirac neutrino states
$\nu_{+}$ and $\overline\nu_{-}$ in the early Universe via weak interactions
and calculate carefully the thermally averaged production rate, taking into
account all the relevant scattering and decay processes. Requiring that the
production rate is less than the Hubble parameter at the onset of QCD phase
transition so that the nucleosynthesis predictions are not contradicted, we
find for $T_{\rm{QCD}}\simeq 200$ MeV the upper limits $m_{\nu_\tau}\lsim 740$
keV and $m_{\nu_\mu}\lsim 480$ keV.
| [
{
"created": "Wed, 25 Nov 1992 18:05:21 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Enqvist",
"K.",
""
],
[
"Uibo",
"H.",
""
]
] | We consider the equilibration of the 'wrong--helicity' Dirac neutrino states $\nu_{+}$ and $\overline\nu_{-}$ in the early Universe via weak interactions and calculate carefully the thermally averaged production rate, taking into account all the relevant scattering and decay processes. Requiring that the production rate is less than the Hubble parameter at the onset of QCD phase transition so that the nucleosynthesis predictions are not contradicted, we find for $T_{\rm{QCD}}\simeq 200$ MeV the upper limits $m_{\nu_\tau}\lsim 740$ keV and $m_{\nu_\mu}\lsim 480$ keV. |
hep-ph/0503187 | Artur Ankowski | Artur M. Ankowski | High-energy limit of neutrino quasielastic cross section | 11 pages, 3 figures | Acta Phys. Pol. B37 (2006) 377 | null | null | hep-ph | null | It's a common knowledge that the quasielastic neutrino-neutron and
antineutrino-proton cross sections tend to the same constant as (anti)neutrino
energy becomes high. In this paper we calculate the exact expression of the
limit in terms of the parameters describing quasielastic scattering. We check
that even at very high energies only small absolute values of the four-momentum
transfer contribute to the cross section, hence the Fermi theory can be
applied. The dipole approximation of the form factors allows to perform
analytic calculations. Obtained results are neutrino-flavour independent.
| [
{
"created": "Fri, 18 Mar 2005 16:12:49 GMT",
"version": "v1"
},
{
"created": "Wed, 23 Mar 2005 18:02:30 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Ankowski",
"Artur M.",
""
]
] | It's a common knowledge that the quasielastic neutrino-neutron and antineutrino-proton cross sections tend to the same constant as (anti)neutrino energy becomes high. In this paper we calculate the exact expression of the limit in terms of the parameters describing quasielastic scattering. We check that even at very high energies only small absolute values of the four-momentum transfer contribute to the cross section, hence the Fermi theory can be applied. The dipole approximation of the form factors allows to perform analytic calculations. Obtained results are neutrino-flavour independent. |
hep-ph/0310006 | Grigory Volovik | G.E. Volovik | Dark matter from SU(4) model | 9 pages, 2 figures, version accepted in JETP Letters, corrected after
referee reports, references are added | Pisma Zh.Eksp.Teor.Fiz. 78 (2003) 1203-1206; JETP Lett. 78 (2003)
691-694 | 10.1134/1.1648287 | null | hep-ph cond-mat gr-qc | null | The left-right symmetric Pati-Salam model of the unification of quarks and
leptons is based on SU(4) and SU(2)xSU(2) groups. These groups are naturally
extended to include the classification of families of quarks and leptons. We
assume that the family group (the group which unites the families) is also the
SU(4) group. The properties of the 4-th generation of fermions are the same as
that of the ordinary-matter fermions in first three generations except for the
family charge of the SU(4)_F group: F=(1/3,1/3,1/3,-1), where F=1/3 for
fermions of ordinary matter and F=-1 for the 4-th generation. The difference in
F does not allow the mixing between ordinary and fourth-generation fermions.
Because of the conservation of the F charge, the creation of baryons and
leptons in the process of electroweak baryogenesis must be accompanied by the
creation of fermions of the 4-th generation. As a result the excess n_B of
baryons over antibaryons leads to the excess n_{\nu 4}=N-\bar N=n_B of
neutrinos over antineutrinos in the 4-th generation. This massive
fourth-generation neutrino may form the non-baryonic dark matter. In principle
their mass density n_{\nu 4}m_N in the Universe can give the main contribution
to the dark matter, since the lower bound on neutrino mass m_N from the data on
decay of the Z-bosons is m_N > m_Z/2. The straightforward prediction of this
model leads to the amount of cold dark matter relative to baryons, which is an
order of magnitude bigger than allowed by observations. This inconsistency may
be avoided by non-conservation of the F-charge.
| [
{
"created": "Wed, 1 Oct 2003 06:43:56 GMT",
"version": "v1"
},
{
"created": "Fri, 3 Oct 2003 13:02:44 GMT",
"version": "v2"
},
{
"created": "Wed, 15 Oct 2003 14:25:04 GMT",
"version": "v3"
},
{
"created": "Thu, 30 Oct 2003 14:10:21 GMT",
"version": "v4"
}
] | 2009-11-10 | [
[
"Volovik",
"G. E.",
""
]
] | The left-right symmetric Pati-Salam model of the unification of quarks and leptons is based on SU(4) and SU(2)xSU(2) groups. These groups are naturally extended to include the classification of families of quarks and leptons. We assume that the family group (the group which unites the families) is also the SU(4) group. The properties of the 4-th generation of fermions are the same as that of the ordinary-matter fermions in first three generations except for the family charge of the SU(4)_F group: F=(1/3,1/3,1/3,-1), where F=1/3 for fermions of ordinary matter and F=-1 for the 4-th generation. The difference in F does not allow the mixing between ordinary and fourth-generation fermions. Because of the conservation of the F charge, the creation of baryons and leptons in the process of electroweak baryogenesis must be accompanied by the creation of fermions of the 4-th generation. As a result the excess n_B of baryons over antibaryons leads to the excess n_{\nu 4}=N-\bar N=n_B of neutrinos over antineutrinos in the 4-th generation. This massive fourth-generation neutrino may form the non-baryonic dark matter. In principle their mass density n_{\nu 4}m_N in the Universe can give the main contribution to the dark matter, since the lower bound on neutrino mass m_N from the data on decay of the Z-bosons is m_N > m_Z/2. The straightforward prediction of this model leads to the amount of cold dark matter relative to baryons, which is an order of magnitude bigger than allowed by observations. This inconsistency may be avoided by non-conservation of the F-charge. |
2312.08339 | Ayala Glick-Magid | Ayala Glick-Magid | Non-relativistic nuclear reduction for tensor couplings in dark matter
direct detection and $\mu \to e$ conversion | 9 pages, 3 tables (additional terms and operators) | null | null | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Nonrelativistic Effective Theory (NRET) is widely used in dark matter
direct detection and charged-lepton flavor violation studies through $\mu \to
e$ conversion. However, existing literature has not fully considered tensor
couplings. This study bridges this gap by utilizing an innovative tensor
decomposition method, extending NRET to incorporate previously overlooked
tensor interactions. We find additional operators in the $\mu \to e$ conversion
that are not present in the scalar and vector couplings. This development is
expected to have a significant impact on ongoing experiments seeking physics
beyond the Standard Model and on our understanding of the new-physics
interactions. To support further research and experimental analyses,
comprehensive tables featuring tensor matrix elements and their corresponding
operators are provided.
| [
{
"created": "Wed, 13 Dec 2023 18:15:38 GMT",
"version": "v1"
},
{
"created": "Fri, 3 May 2024 16:48:07 GMT",
"version": "v2"
}
] | 2024-05-06 | [
[
"Glick-Magid",
"Ayala",
""
]
] | The Nonrelativistic Effective Theory (NRET) is widely used in dark matter direct detection and charged-lepton flavor violation studies through $\mu \to e$ conversion. However, existing literature has not fully considered tensor couplings. This study bridges this gap by utilizing an innovative tensor decomposition method, extending NRET to incorporate previously overlooked tensor interactions. We find additional operators in the $\mu \to e$ conversion that are not present in the scalar and vector couplings. This development is expected to have a significant impact on ongoing experiments seeking physics beyond the Standard Model and on our understanding of the new-physics interactions. To support further research and experimental analyses, comprehensive tables featuring tensor matrix elements and their corresponding operators are provided. |
hep-ph/9507367 | Paul Hoyer | Paul Hoyer and C. S. Lam | The Interpretation of Rapidity Gaps at Hera | 16 pages, latex, 1 uuencoded eps figure in a separate file | Z.Phys. C70 (1996) 449-454 | null | NORDITA-95/53 P | hep-ph | null | In leading twist deep inelastic $ep$ scattering, the virtual photon
interaction is fast compared to the time scale of soft color rearrangement. We
compare the Pomeron exchange model, in which a neutral cluster is preformed,
with a gluon exchange model, in which color is exchanged after the hard
interaction. We find several features of the DIS data and of data on exclusive
hard processes that favor a gluon exchange scenario. If correct, the postulate
of soft color interactions between the produced ($q\bar q$) system and the
target has important implications for other processes. In particular, this may
explain the puzzles of charmonium hadroproduction.
| [
{
"created": "Fri, 21 Jul 1995 10:09:58 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Hoyer",
"Paul",
""
],
[
"Lam",
"C. S.",
""
]
] | In leading twist deep inelastic $ep$ scattering, the virtual photon interaction is fast compared to the time scale of soft color rearrangement. We compare the Pomeron exchange model, in which a neutral cluster is preformed, with a gluon exchange model, in which color is exchanged after the hard interaction. We find several features of the DIS data and of data on exclusive hard processes that favor a gluon exchange scenario. If correct, the postulate of soft color interactions between the produced ($q\bar q$) system and the target has important implications for other processes. In particular, this may explain the puzzles of charmonium hadroproduction. |
1206.6362 | Celso C. Nishi | A. G. Dias, A. C. B. Machado, C. C. Nishi | An $S_3$ Model for Lepton Mass Matrices with Nearly Minimal Texture | 11pp, 2 figures. v2: vev alignment addressed, additional analysis
performed; to appear in PRD | Phys. Rev. D 86, 093005 (2012) | 10.1103/PhysRevD.86.093005 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a simple extension of the electroweak standard model based on the
discrete $S_3$ symmetry that is capable of realizing a nearly minimal
Fritzsch-type texture for the Dirac mass matrices of both charged leptons and
neutrinos. This is achieved with the aid of additional $Z_5$ and $Z_3$
symmetries, one of which can be embedded in $U(1)_{B-L}$. Five complex scalar
singlet fields are introduced in addition to the SM with right-handed
neutrinos. Although more general, the modified texture of the model retains the
successful features of the minimal texture without fine-tuning; namely, it
accommodates the masses and mixing of the leptonic sector and relates the
emergence of large leptonic mixing angles with the seesaw mechanism. For large
deviations of the minimal texture, both quasidegenerate spectrum or inverted
hierarchy are allowed for neutrino masses.
| [
{
"created": "Wed, 27 Jun 2012 18:39:17 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Oct 2012 12:12:34 GMT",
"version": "v2"
}
] | 2015-03-20 | [
[
"Dias",
"A. G.",
""
],
[
"Machado",
"A. C. B.",
""
],
[
"Nishi",
"C. C.",
""
]
] | We propose a simple extension of the electroweak standard model based on the discrete $S_3$ symmetry that is capable of realizing a nearly minimal Fritzsch-type texture for the Dirac mass matrices of both charged leptons and neutrinos. This is achieved with the aid of additional $Z_5$ and $Z_3$ symmetries, one of which can be embedded in $U(1)_{B-L}$. Five complex scalar singlet fields are introduced in addition to the SM with right-handed neutrinos. Although more general, the modified texture of the model retains the successful features of the minimal texture without fine-tuning; namely, it accommodates the masses and mixing of the leptonic sector and relates the emergence of large leptonic mixing angles with the seesaw mechanism. For large deviations of the minimal texture, both quasidegenerate spectrum or inverted hierarchy are allowed for neutrino masses. |
hep-ph/9411320 | D. P. Roy | D.P. Roy | Physics Prospects at the Hadron Colliders | 16 pages Latex + 15 figures (available on request) | Pramana 45 (1995) S293-S312 | 10.1007/BF02907980 | TIFR/TH/94-45 (To be published in the Proceedings of WHEPP-3, the
3rd Workshop on High Energy Physics Phenomenology, Madras, India, 1994) | hep-ph | null | I start with a brief introduction to the elementary particles and their
interactions, Higgs mechanism and supersymmetry. The major physics objectives
of the Tevatron and LHC colliders are identified. The status and prospects of
the top quark, charged Higgs boson and superparticle searches are discussed in
detail, while those of the neutral Higgs boson(s) are covered in a parallel
talk by R.J.N. Phillips at this workshop.
| [
{
"created": "Thu, 17 Nov 1994 10:18:56 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Roy",
"D. P.",
""
]
] | I start with a brief introduction to the elementary particles and their interactions, Higgs mechanism and supersymmetry. The major physics objectives of the Tevatron and LHC colliders are identified. The status and prospects of the top quark, charged Higgs boson and superparticle searches are discussed in detail, while those of the neutral Higgs boson(s) are covered in a parallel talk by R.J.N. Phillips at this workshop. |
hep-ph/0411321 | Andrea Ferroglia | R. Bonciani, A. Ferroglia, P. Mastrolia, E. Remiddi, J. J. van der Bij | Two-Loop N_F =1 QED Bhabha Scattering: Soft Emission and Numerical
Evaluation of the Differential Cross-section | 24 pages, 15 figures. Formulas in Appendix B corrected, changes in
Section 3, references added | Nucl.Phys. B716 (2005) 280-302 | 10.1016/j.nuclphysb.2005.03.010 | null | hep-ph | null | Recently, we evaluated the virtual cross-section for Bhabha scattering in
pure QED, up to corrections of order alpha^4 (N_F =1). This calculation is
valid for arbitrary values of the squared center of mass energy s and momentum
transfer t; the electron and positron mass m was considered a finite, non
vanishing quantity. In the present work, we supplement the previous calculation
by considering the contribution of the soft photon emission diagrams to the
differential cross-section, up to and including terms of order alpha^4 (N_F=1).
Adding the contribution of the real corrections to the renormalized virtual
ones, we obtain an UV and IR finite differential cross-section; we evaluate
this quantity numerically for a significant set of values of the squared center
of mass energy s.
| [
{
"created": "Wed, 24 Nov 2004 13:47:04 GMT",
"version": "v1"
},
{
"created": "Thu, 11 May 2006 15:49:33 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Bonciani",
"R.",
""
],
[
"Ferroglia",
"A.",
""
],
[
"Mastrolia",
"P.",
""
],
[
"Remiddi",
"E.",
""
],
[
"van der Bij",
"J. J.",
""
]
] | Recently, we evaluated the virtual cross-section for Bhabha scattering in pure QED, up to corrections of order alpha^4 (N_F =1). This calculation is valid for arbitrary values of the squared center of mass energy s and momentum transfer t; the electron and positron mass m was considered a finite, non vanishing quantity. In the present work, we supplement the previous calculation by considering the contribution of the soft photon emission diagrams to the differential cross-section, up to and including terms of order alpha^4 (N_F=1). Adding the contribution of the real corrections to the renormalized virtual ones, we obtain an UV and IR finite differential cross-section; we evaluate this quantity numerically for a significant set of values of the squared center of mass energy s. |
hep-ph/0103087 | Christoph Greub | H.H. Asatryan, H.M. Asatrian, C. Greub and M. Walker | Two-loop virtual corrections to B --> X_s l^+ l^- in the standard model | 14 pages including 4 postscript figures | Phys.Lett.B507:162-172,2001 | 10.1016/S0370-2693(01)00441-5 | BUTP-01/06 | hep-ph | null | We calculate O(alpha_s) two-loop virtual corrections to the differential
decay width dGamma(B --> X_s l^+ l^-)/ds, where s is the invariant mass squared
of the lepton pair. We also include those contributions from gluon
bremsstrahlung which are needed to cancel infrared and collinear singularities
present in the virtual corrections. Our calculation is restricted to the range
0.05 < s/m_b^2 < 0.25 where the effects from resonances are small. The new
contributions drastically reduce the renormalization scale dependence of
existing results for dGamma(B --> X_s l^+ l^-)/ds. For the corresponding
branching ratio (restricted to the above s-range) the renormalization scale
uncertainty gets reduced from +/- 13% to +/- 6.5%.
| [
{
"created": "Thu, 8 Mar 2001 17:38:54 GMT",
"version": "v1"
}
] | 2011-01-05 | [
[
"Asatryan",
"H. H.",
""
],
[
"Asatrian",
"H. M.",
""
],
[
"Greub",
"C.",
""
],
[
"Walker",
"M.",
""
]
] | We calculate O(alpha_s) two-loop virtual corrections to the differential decay width dGamma(B --> X_s l^+ l^-)/ds, where s is the invariant mass squared of the lepton pair. We also include those contributions from gluon bremsstrahlung which are needed to cancel infrared and collinear singularities present in the virtual corrections. Our calculation is restricted to the range 0.05 < s/m_b^2 < 0.25 where the effects from resonances are small. The new contributions drastically reduce the renormalization scale dependence of existing results for dGamma(B --> X_s l^+ l^-)/ds. For the corresponding branching ratio (restricted to the above s-range) the renormalization scale uncertainty gets reduced from +/- 13% to +/- 6.5%. |
1901.02946 | Jorge Gamboa | Paola Arias, Jorge Gamboa and Natalia Tapia | Anapole Dark Matter Interactions as Soft Hidden Photons | typos and references added, accepted in PLB | null | 10.1016/j.physletb.2019.02.021 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a model where the anapole appears as a hidden photon that is
coupled to visible matter through a kinetic mixing. For low momentum $|{\bf p}|
\ll M$ where $M$ is the cutoff the model (soft hidden photons limit) is reduced
to the Ho-Scherrer description. We show that the hidden gauge boson is stable
and therefore the hidden photons, indeed, are candidates for dark matter. Our
approach shows that anapole and kinetic mixing terms are equivalent
descriptions seen from different scales of energy.
| [
{
"created": "Wed, 9 Jan 2019 22:04:33 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Feb 2019 22:27:34 GMT",
"version": "v2"
}
] | 2019-02-27 | [
[
"Arias",
"Paola",
""
],
[
"Gamboa",
"Jorge",
""
],
[
"Tapia",
"Natalia",
""
]
] | We propose a model where the anapole appears as a hidden photon that is coupled to visible matter through a kinetic mixing. For low momentum $|{\bf p}| \ll M$ where $M$ is the cutoff the model (soft hidden photons limit) is reduced to the Ho-Scherrer description. We show that the hidden gauge boson is stable and therefore the hidden photons, indeed, are candidates for dark matter. Our approach shows that anapole and kinetic mixing terms are equivalent descriptions seen from different scales of energy. |
1908.05685 | Dimitrios Karamitros | Luc Darm\'e, Andrzej Hryczuk, Dimitrios Karamitros, Leszek Roszkowski | Forbidden frozen-in dark matter | 29 pages, 9 figures; v2: References updated, typos corrected, matches
version published in JHEP | JHEP 1911 (2019) 159 | 10.1007/JHEP11(2019)159 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine and point out the importance of a regime of dark matter production
through the freeze-in mechanism that results from a large thermal correction to
a decaying mediator particle mass from hot plasma in the early Universe. We
show that mediator decays to dark matter that are kinematically forbidden at
the usually considered ranges of low temperatures can be generically present at
higher temperatures and actually dominate the overall dark matter production,
thus leading to very distinct solutions from the standard case. We illustrate
these features by considering a dark Higgs portal model where dark matter is
produced via decays of a scalar field with a large thermal mass. We identify
the resulting ranges of parameters that are consistent with the correct dark
matter relic abundance and further apply current and expected future collider,
cosmological, and astrophysical limits.
| [
{
"created": "Thu, 15 Aug 2019 18:00:01 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Dec 2019 14:51:57 GMT",
"version": "v2"
}
] | 2019-12-03 | [
[
"Darmé",
"Luc",
""
],
[
"Hryczuk",
"Andrzej",
""
],
[
"Karamitros",
"Dimitrios",
""
],
[
"Roszkowski",
"Leszek",
""
]
] | We examine and point out the importance of a regime of dark matter production through the freeze-in mechanism that results from a large thermal correction to a decaying mediator particle mass from hot plasma in the early Universe. We show that mediator decays to dark matter that are kinematically forbidden at the usually considered ranges of low temperatures can be generically present at higher temperatures and actually dominate the overall dark matter production, thus leading to very distinct solutions from the standard case. We illustrate these features by considering a dark Higgs portal model where dark matter is produced via decays of a scalar field with a large thermal mass. We identify the resulting ranges of parameters that are consistent with the correct dark matter relic abundance and further apply current and expected future collider, cosmological, and astrophysical limits. |
hep-ph/9403411 | null | Roberto Peccei | Physics Beyond the Standard Model | 47 pages (figures can be requested from reyes@physics.ucla.edu),
UCLA/94/TEP/11 | null | null | null | hep-ph | null | In these lectures I describe some of the open questions in the standard model
relating to the nature and origin of mass, forces and matter and discuss some
of the speculative theoretical ideas put forth in this regard. Some of the
topics touched upon include supsersymmetry, dynamical symmetry breaking,
composite models, grand unified theories and superstrings.
| [
{
"created": "Fri, 1 Apr 1994 02:09:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Peccei",
"Roberto",
""
]
] | In these lectures I describe some of the open questions in the standard model relating to the nature and origin of mass, forces and matter and discuss some of the speculative theoretical ideas put forth in this regard. Some of the topics touched upon include supsersymmetry, dynamical symmetry breaking, composite models, grand unified theories and superstrings. |
hep-ph/0404120 | Roberto Pittau | F. del Aguila (CAFPE, Granada & Granada U., Theor. Phys. Astrophys.)
and R. Pittau (Granada U., Theor. Phys. Astrophys. & Turin U. & INFN, Turin) | Recursive numerical calculus of one-loop tensor integrals | Typo corrected in formula 79. 22 pages, Latex, 1 figure, uses
axodraw.sty | JHEP 0407:017,2004 | 10.1088/1126-6708/2004/07/017 | UG-FT-162/04 and CAFPE-32/04 | hep-ph | null | A numerical approach to compute tensor integrals in one-loop calculations is
presented. The algorithm is based on a recursion relation which allows to
express high rank tensor integrals as a function of lower rank ones. At each
level of iteration only inverse square roots of Gram determinants appear. For
the phase-space regions where Gram determinants are so small that numerical
problems are expected, we give general prescriptions on how to construct
reliable approximations to the exact result without performing Taylor
expansions. Working in 4+epsilon dimensions does not require an analytic
separation of ultraviolet and infrared/collinear divergences, and, apart from
trivial integrals that we compute explicitly, no additional ones besides the
standard set of scalar one-loop integrals are needed.
| [
{
"created": "Wed, 14 Apr 2004 16:10:07 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Feb 2005 17:28:08 GMT",
"version": "v2"
}
] | 2010-02-03 | [
[
"del Aguila",
"F.",
"",
"CAFPE, Granada & Granada U., Theor. Phys. Astrophys."
],
[
"Pittau",
"R.",
"",
"Granada U., Theor. Phys. Astrophys. & Turin U. & INFN, Turin"
]
] | A numerical approach to compute tensor integrals in one-loop calculations is presented. The algorithm is based on a recursion relation which allows to express high rank tensor integrals as a function of lower rank ones. At each level of iteration only inverse square roots of Gram determinants appear. For the phase-space regions where Gram determinants are so small that numerical problems are expected, we give general prescriptions on how to construct reliable approximations to the exact result without performing Taylor expansions. Working in 4+epsilon dimensions does not require an analytic separation of ultraviolet and infrared/collinear divergences, and, apart from trivial integrals that we compute explicitly, no additional ones besides the standard set of scalar one-loop integrals are needed. |
0808.2782 | Stephen King | S.Boudjemaa and S.F.King | Deviations from Tri-bimaximal Mixing: Charged Lepton Corrections and
Renormalization Group Running | Comparison of numerical results to analytic estimates added. 26
pages, 19 figures | Phys.Rev.D79:033001,2009 | 10.1103/PhysRevD.79.033001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the effects of charged lepton corrections and renormalization
group (RG) running on the low energy predictions of theories which accurately
predict tri-bimaximal neutrino mixing at the high energy scale. In particular
we focus on GUT inspired see-saw models with accurate tri-bimaximal neutrino
mixing at the GUT scale, in which the charged lepton corrections are
Cabibbo-like and give rise to sum rules valid at the GUT scale. We study
numerically the RG corrections to a variety of such neutrino mixing sum rules
in order to assess their accuracy and reliability when comparing them to future
low energy neutrino oscillation experiments. Our results indicate that the RG
corrections to neutrino mixing sum rules are typically small (less than one
degree), at least in the examples studied with hierarchical neutrinos.
| [
{
"created": "Wed, 20 Aug 2008 16:53:28 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Aug 2008 13:44:09 GMT",
"version": "v2"
},
{
"created": "Wed, 26 Nov 2008 09:00:18 GMT",
"version": "v3"
}
] | 2009-02-20 | [
[
"Boudjemaa",
"S.",
""
],
[
"King",
"S. F.",
""
]
] | We analyze the effects of charged lepton corrections and renormalization group (RG) running on the low energy predictions of theories which accurately predict tri-bimaximal neutrino mixing at the high energy scale. In particular we focus on GUT inspired see-saw models with accurate tri-bimaximal neutrino mixing at the GUT scale, in which the charged lepton corrections are Cabibbo-like and give rise to sum rules valid at the GUT scale. We study numerically the RG corrections to a variety of such neutrino mixing sum rules in order to assess their accuracy and reliability when comparing them to future low energy neutrino oscillation experiments. Our results indicate that the RG corrections to neutrino mixing sum rules are typically small (less than one degree), at least in the examples studied with hierarchical neutrinos. |
0812.4494 | Chris Bird | Chris Bird | The Early Universe as a Probe of New Physics | Doctoral Dissertation | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Standard Model of Particle Physics has been verified to unprecedented
precision in the last few decades. However there are still phenomena in nature
which cannot be explained, and as such new theories will be required. Since
terrestrial experiments are limited in both the energy and precision that can
be probed, new methods are required to search for signs of physics beyond the
Standard Model. In this dissertation, I demonstrate how these theories can be
probed by searching for remnants of their effects in the early Universe. In
particular I focus on three possible extensions of the Standard Model: the
addition of massive neutral particles as dark matter (through the use of
several minimal models of dark matter), the addition of charged massive
particles (through catalyzed Big Bang Nucleosynthesis), and the existence of
higher dimensions (through its effects on BBN and galactic positron
production). For each new model, I review the existing experimental bounds and
the potential for discovering new physics in the next generation of
experiments.
| [
{
"created": "Wed, 24 Dec 2008 18:15:07 GMT",
"version": "v1"
}
] | 2008-12-25 | [
[
"Bird",
"Chris",
""
]
] | The Standard Model of Particle Physics has been verified to unprecedented precision in the last few decades. However there are still phenomena in nature which cannot be explained, and as such new theories will be required. Since terrestrial experiments are limited in both the energy and precision that can be probed, new methods are required to search for signs of physics beyond the Standard Model. In this dissertation, I demonstrate how these theories can be probed by searching for remnants of their effects in the early Universe. In particular I focus on three possible extensions of the Standard Model: the addition of massive neutral particles as dark matter (through the use of several minimal models of dark matter), the addition of charged massive particles (through catalyzed Big Bang Nucleosynthesis), and the existence of higher dimensions (through its effects on BBN and galactic positron production). For each new model, I review the existing experimental bounds and the potential for discovering new physics in the next generation of experiments. |
1411.3149 | Werner Vogelsang | Patriz Hinderer, Felix Ringer, George F. Sterman, Werner Vogelsang | Toward NNLL Threshold Resummation for Hadron Pair Production in Hadronic
Collisions | 33 pages, 5 figures. Some references added, minor corrections.
Version to appear in Phys. Rev. D | null | 10.1103/PhysRevD.91.014016 | YITP-SB-14-44 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate QCD threshold resummation effects beyond the next-to-leading
logarithmic (NLL) order for the process H1 H2->h1 h2 X at high invariant mass
of the produced hadron pair. We take into account the color structure of the
underlying partonic hard-scattering cross sections and determine the relevant
hard and soft matrices in color space that contribute to the resummed cross
section at next-to-next-to-leading logarithmic (NNLL) accuracy. We present
numerical results for fixed-target and collider regimes. We find a significant
improvement compared to previous results at NLL accuracy. In particular, the
scale dependence of the resummed cross section is greatly reduced. Use of the
most recent set of fragmentation functions also helps in improving the
comparison with the experimental data. Our calculation provides a step towards
a systematic NNLL extension of threshold resummation also for other hadronic
processes, in particular for jet production.
| [
{
"created": "Wed, 12 Nov 2014 11:36:15 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Dec 2014 17:07:22 GMT",
"version": "v2"
}
] | 2015-06-23 | [
[
"Hinderer",
"Patriz",
""
],
[
"Ringer",
"Felix",
""
],
[
"Sterman",
"George F.",
""
],
[
"Vogelsang",
"Werner",
""
]
] | We investigate QCD threshold resummation effects beyond the next-to-leading logarithmic (NLL) order for the process H1 H2->h1 h2 X at high invariant mass of the produced hadron pair. We take into account the color structure of the underlying partonic hard-scattering cross sections and determine the relevant hard and soft matrices in color space that contribute to the resummed cross section at next-to-next-to-leading logarithmic (NNLL) accuracy. We present numerical results for fixed-target and collider regimes. We find a significant improvement compared to previous results at NLL accuracy. In particular, the scale dependence of the resummed cross section is greatly reduced. Use of the most recent set of fragmentation functions also helps in improving the comparison with the experimental data. Our calculation provides a step towards a systematic NNLL extension of threshold resummation also for other hadronic processes, in particular for jet production. |
1406.2441 | Lei Guo | Guo Lei, Zhang Ren-You and Ma Wen-Gan | Precise calculation for heavy gauge boson production in the LHT model | 12 pages, 6 figures. To appear in the proceedings of 15th
International Workshop on advanced computing and analysis techniques in
physics (ACAT 2013), 16-21 May 2013, Beijing, China | Journal of Physics: Conference Series 523 (2014) 012054 | 10.1088/1742-6596/523/1/012054 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of the littlest Higgs model with $T$ parity, we study the
$W_H/Z_H+q_-$ and $W_H$-pair productions at the CERN Large Hadron Collider up
to the QCD next-to-leading order (NLO). The kinematic distributions of final
decay products and the theoretical dependence of the cross section on the
factorization/renormalization scale are analyzed. We adopt the PROSPINO scheme
in the QCD NLO calculations to avoid double counting and keep the convergence
of the perturbative QCD description. By using the subtraction scheme, the QCD
NLO corrections enhance the leading order cross section with a K-factor in the
range of $1.00 \sim 1.43$ for $W_H(Z_H) q_-$ production process, and in the
range of $1.09 \sim 1.22$ for the $W_H$ pair production process.
| [
{
"created": "Tue, 10 Jun 2014 07:09:23 GMT",
"version": "v1"
}
] | 2014-06-11 | [
[
"Lei",
"Guo",
""
],
[
"Ren-You",
"Zhang",
""
],
[
"Wen-Gan",
"Ma",
""
]
] | In the framework of the littlest Higgs model with $T$ parity, we study the $W_H/Z_H+q_-$ and $W_H$-pair productions at the CERN Large Hadron Collider up to the QCD next-to-leading order (NLO). The kinematic distributions of final decay products and the theoretical dependence of the cross section on the factorization/renormalization scale are analyzed. We adopt the PROSPINO scheme in the QCD NLO calculations to avoid double counting and keep the convergence of the perturbative QCD description. By using the subtraction scheme, the QCD NLO corrections enhance the leading order cross section with a K-factor in the range of $1.00 \sim 1.43$ for $W_H(Z_H) q_-$ production process, and in the range of $1.09 \sim 1.22$ for the $W_H$ pair production process. |
1504.07742 | Pablo Sanchez Puertas | R. Escribano, P. Masjuan, P. Sanchez-Puertas | The eta transition form factor from space- and time-like experimental
data | 16 pages, 17 figures; v2: additional comments, references added;
mathces published version in EPJC | Eur.Phys.J. C75 (2015) 9, 414 | 10.1140/epjc/s10052-015-3642-z | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $\eta$ transition form factor is analysed for the first time in both
space- and time-like regions at low and intermediate energies in a
model-independent approach through the use of rational approximants. The
$\eta\rightarrow e^+e^-\gamma$ experimental data provided by the A2
Collaboration in the very low energy region of the dilelectron invariant mass
distribution allows for the extraction of the most precise up-to-date slope and
curvature parameters of the form factors as well as their values at zero and
infinity. The impact of these new results on the mixing parameters of the
$\eta$-$\eta^\prime$ system, together with the role played by renormalisation
dependent effects, and on the determination of the $VP\gamma$ couplings from
$V\to P\gamma$ and $P\to V\gamma$ radiative decays are also discussed.
| [
{
"created": "Wed, 29 Apr 2015 07:26:56 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Sep 2015 14:30:32 GMT",
"version": "v2"
}
] | 2015-09-17 | [
[
"Escribano",
"R.",
""
],
[
"Masjuan",
"P.",
""
],
[
"Sanchez-Puertas",
"P.",
""
]
] | The $\eta$ transition form factor is analysed for the first time in both space- and time-like regions at low and intermediate energies in a model-independent approach through the use of rational approximants. The $\eta\rightarrow e^+e^-\gamma$ experimental data provided by the A2 Collaboration in the very low energy region of the dilelectron invariant mass distribution allows for the extraction of the most precise up-to-date slope and curvature parameters of the form factors as well as their values at zero and infinity. The impact of these new results on the mixing parameters of the $\eta$-$\eta^\prime$ system, together with the role played by renormalisation dependent effects, and on the determination of the $VP\gamma$ couplings from $V\to P\gamma$ and $P\to V\gamma$ radiative decays are also discussed. |
0901.2849 | Yogiro Hama | Y. Hama, R. P. G. Andrade, F. Grassi, W.-L. Qian (Sao Paulo U.) and T.
Kodama (Rio de Janeiro Federal U.) | Fluctuation of the Initial Conditions and Its Consequences on Some
Observables | 6 pages, 6 figures, presented at the IV Workshop on Particle
Correlations and Femtoscopy (WPCF2008), Krakow, Poland, 11-14 Sep 2008 | Acta Phys.Polon.B40:931-936,2009 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show effects of the event-by-event fluctuation of the initial conditions
(IC) in hydrodynamic description of high-energy nuclear collisions on some
observables. Such IC produce not only fluctuations in observables but, due to
their bumpy structure, several non-trivial effects appear. They enhance
production of isotropically distributed high-pT particles, making v2 smaller
there. Also, they reduce v2 in the forward and backward regions where the
global matter density is smaller, so where such effects become more
efficacious. They may also produce the so-called ridge effect in the two
large-pT particle correlation.
| [
{
"created": "Mon, 19 Jan 2009 13:21:16 GMT",
"version": "v1"
}
] | 2009-04-24 | [
[
"Hama",
"Y.",
"",
"Sao Paulo U."
],
[
"Andrade",
"R. P. G.",
"",
"Sao Paulo U."
],
[
"Grassi",
"F.",
"",
"Sao Paulo U."
],
[
"Qian",
"W. -L.",
"",
"Sao Paulo U."
],
[
"Kodama",
"T.",
"",
"Rio de Janeiro Federal U."
]
] | We show effects of the event-by-event fluctuation of the initial conditions (IC) in hydrodynamic description of high-energy nuclear collisions on some observables. Such IC produce not only fluctuations in observables but, due to their bumpy structure, several non-trivial effects appear. They enhance production of isotropically distributed high-pT particles, making v2 smaller there. Also, they reduce v2 in the forward and backward regions where the global matter density is smaller, so where such effects become more efficacious. They may also produce the so-called ridge effect in the two large-pT particle correlation. |
0807.0066 | Barbara Jager | B. Jager | Photoproduction of single inclusive jets at future ep colliders in
next-to-leading order QCD | 17 pages, 8 figures | Phys.Rev.D78:034017,2008 | 10.1103/PhysRevD.78.034017 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A next-to-leading order QCD calculation for single-inclusive jet
photoproduction in unpolarized and longitudinally polarized lepton-hadron
collisions is presented which consistently includes ``direct'' and ``resolved''
photon contributions. The computation is performed within the ``small-cone
approximation'' in a largely analytical form. Phenomenological aspects of jet
production at future ep colliders such as the CERN-LHeC and the polarized
BNL-eRHIC are discussed, placing particular emphasis on the perturbative
stability of the predictions and the possibility to constrain the parton
content of the photon.
| [
{
"created": "Tue, 1 Jul 2008 04:19:08 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Jager",
"B.",
""
]
] | A next-to-leading order QCD calculation for single-inclusive jet photoproduction in unpolarized and longitudinally polarized lepton-hadron collisions is presented which consistently includes ``direct'' and ``resolved'' photon contributions. The computation is performed within the ``small-cone approximation'' in a largely analytical form. Phenomenological aspects of jet production at future ep colliders such as the CERN-LHeC and the polarized BNL-eRHIC are discussed, placing particular emphasis on the perturbative stability of the predictions and the possibility to constrain the parton content of the photon. |
1303.4603 | Octavian Micu | Nicusor Arsene, Xavier Calmet, Laurentiu Ioan Caramete, Octavian Micu | Back-to-Back Black Holes decay Signature at Neutrino Observatories | 8 pages, 4 figures | null | 10.1016/j.astropartphys.2013.12.005 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a decay signature for non-thermal small black holes with masses in
the TeV range which can be discovered by neutrino observatories. The black
holes would result due to the impact between ultra high energy neutrinos with
nuclei in water or ice and decay instantaneously. They could be produced if the
Planck scale is in the few TeV region and the highly energetic fluxes are large
enough. Having masses close to the Planck scale, the typical decay mode for
these black holes is into two particles emitted back-to-back. For a certain
range of angles between the emitted particles and the center of mass direction
of motion, it is possible for the detectors to measure separate muons having
specific energies and their trajectories oriented at a large enough angle to
prove that they are the result of a back-to-back decay event.
| [
{
"created": "Tue, 19 Mar 2013 14:11:26 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Mar 2013 11:42:36 GMT",
"version": "v2"
},
{
"created": "Mon, 8 Jul 2013 11:21:21 GMT",
"version": "v3"
},
{
"created": "Mon, 6 Jan 2014 16:40:42 GMT",
"version": "v4"
}
] | 2015-06-15 | [
[
"Arsene",
"Nicusor",
""
],
[
"Calmet",
"Xavier",
""
],
[
"Caramete",
"Laurentiu Ioan",
""
],
[
"Micu",
"Octavian",
""
]
] | We propose a decay signature for non-thermal small black holes with masses in the TeV range which can be discovered by neutrino observatories. The black holes would result due to the impact between ultra high energy neutrinos with nuclei in water or ice and decay instantaneously. They could be produced if the Planck scale is in the few TeV region and the highly energetic fluxes are large enough. Having masses close to the Planck scale, the typical decay mode for these black holes is into two particles emitted back-to-back. For a certain range of angles between the emitted particles and the center of mass direction of motion, it is possible for the detectors to measure separate muons having specific energies and their trajectories oriented at a large enough angle to prove that they are the result of a back-to-back decay event. |
hep-ph/0609138 | Antonio Pich | Antonio Pich | Theoretical overview on tau physics | Invited talk at the International Workshop on Tau-Charm Physics
(Charm2006), Beijing, China, June 5-7, 2006. 8 pages, 2 figures | Int.J.Mod.Phys. A21 (2006) 5652-5659 | 10.1142/S0217751X06034860 | IFIC/06-27, FTUV/06-0914 | hep-ph | null | Precise measurements of the tau lepton properties provide stringent tests of
the Standard Model structure and accurate determinations of its parameters. We
overview the present status of a few selected topics: lepton universality, QCD
tests and the determination of alpha_s, m_s and V_us from hadronic tau decays,
and lepton flavor violation phenomena.
| [
{
"created": "Thu, 14 Sep 2006 14:46:47 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Pich",
"Antonio",
""
]
] | Precise measurements of the tau lepton properties provide stringent tests of the Standard Model structure and accurate determinations of its parameters. We overview the present status of a few selected topics: lepton universality, QCD tests and the determination of alpha_s, m_s and V_us from hadronic tau decays, and lepton flavor violation phenomena. |
1611.06622 | Wojciech Kotlarski | Wojciech Kotlarski | Analysis of the R-symmetric supersymmetric models including quantum
corrections | PhD thesis, 142 pages, University of Warsaw, September 2016 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the Minimal R-symmetric Supersymmetric Standard Model (MRSSM) at the
quantum level. The thesis consists of two parts. First one treats about the
electroweak sector of the model. Among others, it identifies the parameter
region allowed by the electroweak precision observables. Since the MRSSM
contains an $SU(2)_L$-triplet with a non-zero vacuum expectation value the
emphasis is put on the calculation of the $W$ boson mass. To that end, a full
one-loop calculation of $m_W$ augmented with the leading two-loop SM result is
presented. The region is then checked against the measurement of the Higgs
boson mass. For this, the full one-loop and leading two-loop corrections to the
Higgs boson mass in the MRSSM are calculated. Devised benchmark points,
consistent with both of these observables, are shown to fulfill also a number
of additional experimental constraints like properties of the Higgs boson(s),
$b$-physics observables and vacuum stability. Correlating all of these
observables allows to put bounds on the parameters of the model. Second part of
the thesis treats about the strongly interacting scalar sector. First, NLO QCD
corrections to the production of scalar gluon (sgluon) pair at the LHC are
calculated. A set of $K$-factors for a selected sgluon masses at 13 and 14 TeV
LHC is presented. This calculation is applied to constrain the sgluon mass
using 2015 data set from Run 2 of the LHC. To that end, a same-sign lepton
search by ATLAS is recasted for the case of the production of the sgluon pair
decaying to $t\bar{t}$ pairs. The analysis is reproduced with the help of
shower Monte Carlo softwares and the program performing a fast detector
response simulation. The analysis shows that already using 3.2/fb of integrated
luminosity the exclusion limits from Run 2 are competitive with the 8 TeV ones.
| [
{
"created": "Mon, 21 Nov 2016 01:03:05 GMT",
"version": "v1"
}
] | 2016-11-22 | [
[
"Kotlarski",
"Wojciech",
""
]
] | We study the Minimal R-symmetric Supersymmetric Standard Model (MRSSM) at the quantum level. The thesis consists of two parts. First one treats about the electroweak sector of the model. Among others, it identifies the parameter region allowed by the electroweak precision observables. Since the MRSSM contains an $SU(2)_L$-triplet with a non-zero vacuum expectation value the emphasis is put on the calculation of the $W$ boson mass. To that end, a full one-loop calculation of $m_W$ augmented with the leading two-loop SM result is presented. The region is then checked against the measurement of the Higgs boson mass. For this, the full one-loop and leading two-loop corrections to the Higgs boson mass in the MRSSM are calculated. Devised benchmark points, consistent with both of these observables, are shown to fulfill also a number of additional experimental constraints like properties of the Higgs boson(s), $b$-physics observables and vacuum stability. Correlating all of these observables allows to put bounds on the parameters of the model. Second part of the thesis treats about the strongly interacting scalar sector. First, NLO QCD corrections to the production of scalar gluon (sgluon) pair at the LHC are calculated. A set of $K$-factors for a selected sgluon masses at 13 and 14 TeV LHC is presented. This calculation is applied to constrain the sgluon mass using 2015 data set from Run 2 of the LHC. To that end, a same-sign lepton search by ATLAS is recasted for the case of the production of the sgluon pair decaying to $t\bar{t}$ pairs. The analysis is reproduced with the help of shower Monte Carlo softwares and the program performing a fast detector response simulation. The analysis shows that already using 3.2/fb of integrated luminosity the exclusion limits from Run 2 are competitive with the 8 TeV ones. |
hep-ph/0109209 | null | Carlos Quimbay, John Morales (Universidad Nacional de Colombia) | Rest masses of elementary particles as effective masses at zero
temperature | LATEX file, 25 pages, 3 eps figures. Corrected typos | null | null | FIUN-CP-01/1 | hep-ph cond-mat hep-th | null | We introduce a new approach to generate dinamically the masses of elementary
particles in the $SU(3)_C \times SU(2)_L \times U(1)_Y$ Standard Model without
Higgs Sector (SMWHS). We start from the assumption that rest masses correspond
to the effective masses of particles in an elementary quantum fluid at zero
temperature. These effective masses are obtained through radiative corrections,
at one-loop order, in the context of the real time formalism of quantum field
theory at finite temperature and density. The quantum fluid is described in
structure and dynamics by the SMWHS and it is characterized by non-vanishing
chemical potentials associated to the different fermion flavour species.
Starting from the experimental mass values for quarks and leptons, taking the
top quark mass as $m_t = 172.916$ GeV, we can compute, as an evidence of the
consistency of our approach, the experimental central mass values for the
$W^{\pm}$ and $Z^0$ gauge bosons. Subsequently we introduce in the SMWHS a
massless scalar field leading to Yukawa coupling terms in the Lagrangian
density. For this case we can also compute the experimental mass central values
of the $W^{\pm}$ and $Z^0$ gauge bosons using a top quark mass value in the
range 169.2 GeV $< m_{t} < 178.6$ GeV; this range for the top quark mass
implies that the scalar boson mass must be in the range $0 < M_{H} < 152$ GeV.
| [
{
"created": "Mon, 24 Sep 2001 00:35:44 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Oct 2001 16:54:41 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Quimbay",
"Carlos",
"",
"Universidad Nacional de Colombia"
],
[
"Morales",
"John",
"",
"Universidad Nacional de Colombia"
]
] | We introduce a new approach to generate dinamically the masses of elementary particles in the $SU(3)_C \times SU(2)_L \times U(1)_Y$ Standard Model without Higgs Sector (SMWHS). We start from the assumption that rest masses correspond to the effective masses of particles in an elementary quantum fluid at zero temperature. These effective masses are obtained through radiative corrections, at one-loop order, in the context of the real time formalism of quantum field theory at finite temperature and density. The quantum fluid is described in structure and dynamics by the SMWHS and it is characterized by non-vanishing chemical potentials associated to the different fermion flavour species. Starting from the experimental mass values for quarks and leptons, taking the top quark mass as $m_t = 172.916$ GeV, we can compute, as an evidence of the consistency of our approach, the experimental central mass values for the $W^{\pm}$ and $Z^0$ gauge bosons. Subsequently we introduce in the SMWHS a massless scalar field leading to Yukawa coupling terms in the Lagrangian density. For this case we can also compute the experimental mass central values of the $W^{\pm}$ and $Z^0$ gauge bosons using a top quark mass value in the range 169.2 GeV $< m_{t} < 178.6$ GeV; this range for the top quark mass implies that the scalar boson mass must be in the range $0 < M_{H} < 152$ GeV. |
0904.2246 | Harleen Dahiya Dr. | Neetika Sharma, Harleen Dahiya, P.K. Chatley, Manmohan Gupta | Weak vector and axial-vector form factors in the chiral constituent
quark model with configuration mixing | 11 pages, 3 Tables. To appear in Phys. Rev. D | Phys.Rev.D79:077503,2009 | 10.1103/PhysRevD.79.077503 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The effects of SU(3) symmetry breaking and configuration mixing have been
investigated for the weak vector and axial-vector form factors in the chiral
constituent quark model (\chi CQM) for the strangeness changing as well as
strangeness conserving semi-leptonic octet baryon decays in the nonperturbative
regime. The results are in good agreement with existing experimental data and
also show improvement over other phenomenological models.
| [
{
"created": "Wed, 15 Apr 2009 06:48:22 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Sharma",
"Neetika",
""
],
[
"Dahiya",
"Harleen",
""
],
[
"Chatley",
"P. K.",
""
],
[
"Gupta",
"Manmohan",
""
]
] | The effects of SU(3) symmetry breaking and configuration mixing have been investigated for the weak vector and axial-vector form factors in the chiral constituent quark model (\chi CQM) for the strangeness changing as well as strangeness conserving semi-leptonic octet baryon decays in the nonperturbative regime. The results are in good agreement with existing experimental data and also show improvement over other phenomenological models. |
1611.04322 | Naoyuki Takeda | Tetsutaro Higaki, Michinobu Nishida, Naoyuki Takeda | Flavor structure, Higgs boson mass and dark matter in supersymmetric
model with vector-like generations | 43 pages, 4 figures, Accepted by Progress of Theoretical and
Experimental Physics (PTEP) | Prog Theor Exp Phys (2017) | 10.1093/ptep/ptx104 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study a supersymmetric model in which the Higgs mass, the muon anomalous
magnetic moment and the dark matter are simultaneously explained with extra
vector-like generation multiplets. For the explanations, non-trivial flavor
structures and a singlet field are required. In this paper, we study the flavor
texture by using the Froggatt-Nielsen mechanism, and then find realistic flavor
structures which reproduce the Cabbibo-Kobayashi-Maskawa matrix and fermion
masses at low energy. Furthermore, we find that the fermion component of the
singlet field becomes a good candidate of dark matter. In our model, flavor
physics and dark matter are explained with moderate size couplings through
renormalization group flows, and the presence of dark matter supports the
existence of just three generations in low energy scales. We analyze the
parameter region where the current thermal relic abundance of dark matter, the
Higgs boson mass and the muon $g-2$ can be explained simultaneously.
| [
{
"created": "Mon, 14 Nov 2016 10:25:34 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Jul 2017 11:41:11 GMT",
"version": "v2"
}
] | 2019-12-06 | [
[
"Higaki",
"Tetsutaro",
""
],
[
"Nishida",
"Michinobu",
""
],
[
"Takeda",
"Naoyuki",
""
]
] | We study a supersymmetric model in which the Higgs mass, the muon anomalous magnetic moment and the dark matter are simultaneously explained with extra vector-like generation multiplets. For the explanations, non-trivial flavor structures and a singlet field are required. In this paper, we study the flavor texture by using the Froggatt-Nielsen mechanism, and then find realistic flavor structures which reproduce the Cabbibo-Kobayashi-Maskawa matrix and fermion masses at low energy. Furthermore, we find that the fermion component of the singlet field becomes a good candidate of dark matter. In our model, flavor physics and dark matter are explained with moderate size couplings through renormalization group flows, and the presence of dark matter supports the existence of just three generations in low energy scales. We analyze the parameter region where the current thermal relic abundance of dark matter, the Higgs boson mass and the muon $g-2$ can be explained simultaneously. |
hep-ph/9606392 | Darrell Tonge | C.J.Maxwell and D.G.Tonge (Centre for Particle Theory, Durham) | RS-invariant all-orders renormalon resummations for some QCD observables | 25 pages, uses LaTeX, 12 Postscript figures, epsfig.sty 'elsart.sty'
and 'elsart12.sty' are available via anonymous-ftp at
ftp://ftp.tex.ac.uk/tex-archive/macros/latex/contrib/supported/elsevier | Nucl.Phys. B481 (1996) 681-703 | 10.1016/S0550-3213(96)00532-9 | DTP/96/52 | hep-ph | null | We propose a renormalon-inspired resummation of QCD perturbation theory based
on approximating the renormalization scheme (RS) invariant effective charge
beta-function coefficients by the portion containing the highest power of
$b$=$\frac{1}{6}(11N$--$2N_{f})$, for SU($N$) QCD with $N_{f}$ quark flavours.
This can be accomplished using exact large-$N_{f}$ all-orders results. The
resulting resummation is RS-invariant and the exact next-to-leading order (NLO)
and next-to-NLO (NNLO) coefficients in any RS are included. This improves on a
previously employed naive resummation of the leading-$b$ piece of the
perturbative coefficients which is RS-dependent, making its comparison with
fixed-order perturbative results ambiguous. The RS-invariant resummation is
used to assess the reliability of fixed-order perturbation theory for the
$e^{+}e^{-}$ $R$-ratio, the analogous $\tau$-lepton decay ratio $R_{\tau}$, and
Deep Inelastic Scattering (DIS) sum rules, by comparing it with the exact NNLO
results in the effective charge RS. For the $R$-ratio and $R_{\tau}$, where
large-order perturbative behaviour is dominated by a leading ultra-violet
renormalon singularity, the comparison indicates fixed-order perturbation
theory to be very reliable. For DIS sum rules, which have a leading infra-red
renormalon singularity, the performance is rather poor. In this way we estimate
that at LEP/SLD energies ideal data on the $R$-ratio could determine
$\alpha_{s}(M_{Z})$ to three-significant figures, and for the $R_{\tau}$ we
estimate a theoretical uncertainty $\delta\alpha_{s}(m_{\tau})\simeq0.008$
corresponding to $\delta\alpha_{s}(M_{Z})\simeq0.001$. This encouragingly small
uncertainty is much less than has recently been deduced from comparison with
the ambiguous naive resummation.
| [
{
"created": "Thu, 20 Jun 1996 20:40:01 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Maxwell",
"C. J.",
"",
"Centre for Particle Theory, Durham"
],
[
"Tonge",
"D. G.",
"",
"Centre for Particle Theory, Durham"
]
] | We propose a renormalon-inspired resummation of QCD perturbation theory based on approximating the renormalization scheme (RS) invariant effective charge beta-function coefficients by the portion containing the highest power of $b$=$\frac{1}{6}(11N$--$2N_{f})$, for SU($N$) QCD with $N_{f}$ quark flavours. This can be accomplished using exact large-$N_{f}$ all-orders results. The resulting resummation is RS-invariant and the exact next-to-leading order (NLO) and next-to-NLO (NNLO) coefficients in any RS are included. This improves on a previously employed naive resummation of the leading-$b$ piece of the perturbative coefficients which is RS-dependent, making its comparison with fixed-order perturbative results ambiguous. The RS-invariant resummation is used to assess the reliability of fixed-order perturbation theory for the $e^{+}e^{-}$ $R$-ratio, the analogous $\tau$-lepton decay ratio $R_{\tau}$, and Deep Inelastic Scattering (DIS) sum rules, by comparing it with the exact NNLO results in the effective charge RS. For the $R$-ratio and $R_{\tau}$, where large-order perturbative behaviour is dominated by a leading ultra-violet renormalon singularity, the comparison indicates fixed-order perturbation theory to be very reliable. For DIS sum rules, which have a leading infra-red renormalon singularity, the performance is rather poor. In this way we estimate that at LEP/SLD energies ideal data on the $R$-ratio could determine $\alpha_{s}(M_{Z})$ to three-significant figures, and for the $R_{\tau}$ we estimate a theoretical uncertainty $\delta\alpha_{s}(m_{\tau})\simeq0.008$ corresponding to $\delta\alpha_{s}(M_{Z})\simeq0.001$. This encouragingly small uncertainty is much less than has recently been deduced from comparison with the ambiguous naive resummation. |
1503.00691 | Ulrich Haisch | Ulrich Haisch and Emanuele Re | Simplified dark matter top-quark interactions at the LHC | 29 pages, 11 figures; v4: conflict with CERN-PH-TH number fixed | null | null | OUTP-15-02P, CERN-PH-TH-2015-201 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Stringent limits on the interactions between dark matter (DM) and the
standard model can be set by studying how initial-state or final-state
particles recoil against missing transverse energy (MET). In this work, we
improve, extend and correct LHC constraints on the interactions between DM and
top quarks that are mediated by the exchange of spin-0 s-channel resonances. A
comparison of the LHC run-1 sensitivity of the two main search channels is
presented, which shows that mono-jet searches are typically more restrictive
than the MET + tbar t searches. We furthermore explore the reach of the 14 TeV
LHC. The collider constraints are compared to the restrictions arising from
direct and indirect detection as well as the DM relic abundance, and we also
reflect on effective field theory interpretations of the LHC exclusions.
| [
{
"created": "Mon, 2 Mar 2015 20:19:29 GMT",
"version": "v1"
},
{
"created": "Fri, 3 Jul 2015 09:30:34 GMT",
"version": "v2"
},
{
"created": "Wed, 19 Aug 2015 11:11:40 GMT",
"version": "v3"
},
{
"created": "Thu, 20 Aug 2015 09:13:19 GMT",
"version": "v4"
}
] | 2015-08-21 | [
[
"Haisch",
"Ulrich",
""
],
[
"Re",
"Emanuele",
""
]
] | Stringent limits on the interactions between dark matter (DM) and the standard model can be set by studying how initial-state or final-state particles recoil against missing transverse energy (MET). In this work, we improve, extend and correct LHC constraints on the interactions between DM and top quarks that are mediated by the exchange of spin-0 s-channel resonances. A comparison of the LHC run-1 sensitivity of the two main search channels is presented, which shows that mono-jet searches are typically more restrictive than the MET + tbar t searches. We furthermore explore the reach of the 14 TeV LHC. The collider constraints are compared to the restrictions arising from direct and indirect detection as well as the DM relic abundance, and we also reflect on effective field theory interpretations of the LHC exclusions. |
1702.07704 | Sofia Leit\~ao | Sofia Leit\~ao, Alfred Stadler, M. T. Pe\~na and E. P. Biernat | Relativistic phenomenology of meson spectra with a covariant quark model
in Minkowski space | null | null | 10.1051/epjconf/201713706014 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we perform a covariant treatment of quark-antiquark systems. We
calculate the spectra and wave functions using a formalism based on the
Covariant Spectator Theory (CST). Our results not only reproduce very well the
experimental data with a very small set of global parameters, but they also
allow a direct test of the predictive power of covariant kernels.
| [
{
"created": "Fri, 24 Feb 2017 18:53:10 GMT",
"version": "v1"
}
] | 2017-04-05 | [
[
"Leitão",
"Sofia",
""
],
[
"Stadler",
"Alfred",
""
],
[
"Peña",
"M. T.",
""
],
[
"Biernat",
"E. P.",
""
]
] | In this work, we perform a covariant treatment of quark-antiquark systems. We calculate the spectra and wave functions using a formalism based on the Covariant Spectator Theory (CST). Our results not only reproduce very well the experimental data with a very small set of global parameters, but they also allow a direct test of the predictive power of covariant kernels. |
1509.01598 | Tien-Tien Yu | Rouven Essig, Marivi Fernandez-Serra, Jeremy Mardon, Adrian Soto,
Tomer Volansky, Tien-Tien Yu | Direct Detection of sub-GeV Dark Matter with Semiconductor Targets | 30 pages + 22 pages appendices/references, 17 figures, website at
http://ddldm.physics.sunysb.edu/, v2 added references, minor edits to text
and Figs. 2 and 14, version to appear in JHEP | null | null | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Dark matter in the sub-GeV mass range is a theoretically motivated but
largely unexplored paradigm. Such light masses are out of reach for
conventional nuclear recoil direct detection experiments, but may be detected
through the small ionization signals caused by dark matter-electron scattering.
Semiconductors are well-studied and are particularly promising target materials
because their ${\cal O}(1~\rm{eV})$ band gaps allow for ionization signals from
dark matter as light as a few hundred keV. Current direct detection
technologies are being adapted for dark matter-electron scattering. In this
paper, we provide the theoretical calculations for dark matter-electron
scattering rate in semiconductors, overcoming several complications that stem
from the many-body nature of the problem. We use density functional theory to
numerically calculate the rates for dark matter-electron scattering in silicon
and germanium, and estimate the sensitivity for upcoming experiments such as
DAMIC and SuperCDMS. We find that the reach for these upcoming experiments has
the potential to be orders of magnitude beyond current direct detection
constraints and that sub-GeV dark matter has a sizable modulation signal. We
also give the first direct detection limits on sub-GeV dark matter from its
scattering off electrons in a semiconductor target (silicon) based on published
results from DAMIC. We make available publicly our code, QEdark, with which we
calculate our results. Our results can be used by experimental collaborations
to calculate their own sensitivities based on their specific setup. The
searches we propose will probe vast new regions of unexplored dark matter model
and parameter space.
| [
{
"created": "Fri, 4 Sep 2015 20:24:59 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Apr 2016 16:17:44 GMT",
"version": "v2"
}
] | 2016-04-26 | [
[
"Essig",
"Rouven",
""
],
[
"Fernandez-Serra",
"Marivi",
""
],
[
"Mardon",
"Jeremy",
""
],
[
"Soto",
"Adrian",
""
],
[
"Volansky",
"Tomer",
""
],
[
"Yu",
"Tien-Tien",
""
]
] | Dark matter in the sub-GeV mass range is a theoretically motivated but largely unexplored paradigm. Such light masses are out of reach for conventional nuclear recoil direct detection experiments, but may be detected through the small ionization signals caused by dark matter-electron scattering. Semiconductors are well-studied and are particularly promising target materials because their ${\cal O}(1~\rm{eV})$ band gaps allow for ionization signals from dark matter as light as a few hundred keV. Current direct detection technologies are being adapted for dark matter-electron scattering. In this paper, we provide the theoretical calculations for dark matter-electron scattering rate in semiconductors, overcoming several complications that stem from the many-body nature of the problem. We use density functional theory to numerically calculate the rates for dark matter-electron scattering in silicon and germanium, and estimate the sensitivity for upcoming experiments such as DAMIC and SuperCDMS. We find that the reach for these upcoming experiments has the potential to be orders of magnitude beyond current direct detection constraints and that sub-GeV dark matter has a sizable modulation signal. We also give the first direct detection limits on sub-GeV dark matter from its scattering off electrons in a semiconductor target (silicon) based on published results from DAMIC. We make available publicly our code, QEdark, with which we calculate our results. Our results can be used by experimental collaborations to calculate their own sensitivities based on their specific setup. The searches we propose will probe vast new regions of unexplored dark matter model and parameter space. |
2312.01718 | Zhan-Hong Lei | Chengcheng Han, Zhanhong Lei, Jin Min Yang | Type-II Seesaw Leptogenesis along the Ridge | null | null | null | null | hep-ph astro-ph.CO hep-th | http://creativecommons.org/licenses/by/4.0/ | Type-II seesaw leptogenesis is a model that integrates inflation, baryon
number asymmetry, and neutrino mass simultaneously. It employs the Affleck-Dine
mechanism to generate lepton asymmetry, with the Higgs bosons serving as the
inflaton. Previous studies assumed inflation to occur in a valley of the
potential, employing the single-field approximation. In this work, we explore
an alternative scenario for the type-II seesaw leptogenesis, where the
inflation takes place along a ridge of the potential. Firstly, we conduct a
comprehensive numerical calculation in the canonical scenario, where inflation
occurs in a valley, confirming the effectiveness of the single-field
approximation. Then, we introduce a novel scenario wherein inflation initiates
along the potential's ridge and transitions to the valley in the late stages.
In this case, the single-field inflation approximation is no longer valid, yet
leptogenesis is still successfully achieved. We find that this scenario can
generate a significant non-Gaussianity signature, offering testable predictions
for future experiments.
| [
{
"created": "Mon, 4 Dec 2023 08:19:05 GMT",
"version": "v1"
}
] | 2023-12-05 | [
[
"Han",
"Chengcheng",
""
],
[
"Lei",
"Zhanhong",
""
],
[
"Yang",
"Jin Min",
""
]
] | Type-II seesaw leptogenesis is a model that integrates inflation, baryon number asymmetry, and neutrino mass simultaneously. It employs the Affleck-Dine mechanism to generate lepton asymmetry, with the Higgs bosons serving as the inflaton. Previous studies assumed inflation to occur in a valley of the potential, employing the single-field approximation. In this work, we explore an alternative scenario for the type-II seesaw leptogenesis, where the inflation takes place along a ridge of the potential. Firstly, we conduct a comprehensive numerical calculation in the canonical scenario, where inflation occurs in a valley, confirming the effectiveness of the single-field approximation. Then, we introduce a novel scenario wherein inflation initiates along the potential's ridge and transitions to the valley in the late stages. In this case, the single-field inflation approximation is no longer valid, yet leptogenesis is still successfully achieved. We find that this scenario can generate a significant non-Gaussianity signature, offering testable predictions for future experiments. |
hep-ph/0509049 | Martin Melcher | A. Khodjamirian, Th. Mannel, M. Melcher and B. Melic | Annihilation effects in $B \to \pi\pi$ from QCD Light-Cone Sum Rules | two references added, a few misprints corrected, 38 pages, 29 figures | Phys.Rev.D72:094012,2005 | 10.1103/PhysRevD.72.094012 | SI-HEP-2005-08, IRB-TH-21/05 | hep-ph | null | Using the method of QCD light-cone sum rules, we calculate the $B \to \pi\pi$
hadronic matrix elements with annihilation topology. We obtain a finite result,
including the related strong phase. Numerically, the annihilation effects in
$B\to \pi\pi$ turn out to be small with respect to the factorizable emission
mechanism. Our predictions, together with the earlier sum rule estimates of
emission and penguin contributions, are used for the phenomenological analysis
of $B\to \pi\pi$ channels. We predict a $\Delta I=1/2$ transition amplitude
which significantly differs from this amplitude extracted from the current
data.
| [
{
"created": "Tue, 6 Sep 2005 14:51:27 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Nov 2005 13:10:47 GMT",
"version": "v2"
}
] | 2014-11-18 | [
[
"Khodjamirian",
"A.",
""
],
[
"Mannel",
"Th.",
""
],
[
"Melcher",
"M.",
""
],
[
"Melic",
"B.",
""
]
] | Using the method of QCD light-cone sum rules, we calculate the $B \to \pi\pi$ hadronic matrix elements with annihilation topology. We obtain a finite result, including the related strong phase. Numerically, the annihilation effects in $B\to \pi\pi$ turn out to be small with respect to the factorizable emission mechanism. Our predictions, together with the earlier sum rule estimates of emission and penguin contributions, are used for the phenomenological analysis of $B\to \pi\pi$ channels. We predict a $\Delta I=1/2$ transition amplitude which significantly differs from this amplitude extracted from the current data. |
hep-ph/0204057 | Chongxing Yue | Chongxing Yue, Yuanben Dai, Hong Li | The dynamical models and the $Z \to b \bar{b}$ asymmetry} | Latex files, 13 pages and 1 figure | Mod.Phys.Lett. A17 (2002) 261-268 | 10.1142/S0217732302006448 | null | hep-ph | null | Motivated by the $3.2\sigma(1.4\sigma)$ deviations between the recent
experimental value for $A_{FB}^{b}(R_{b})$ and the standard model(SM)
prediction, we examine the effect of new physics(NP) on the $Zb \bar{b}$
couplings $g_L^b$ and $g_R^b$. First we focus our attention on the dynamical
models. Then, using effective lagrangean techniques, we discuss the corrections
of NP to $g_L^b$ and $g_R^b$. We find some kinds of NP might explain the
recently experimental data about $R_b$ and $A_{FB}^b$. However, the free
parameters of these kinds of NP must be severely constrained.
| [
{
"created": "Thu, 4 Apr 2002 14:52:08 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Yue",
"Chongxing",
""
],
[
"Dai",
"Yuanben",
""
],
[
"Li",
"Hong",
""
]
] | Motivated by the $3.2\sigma(1.4\sigma)$ deviations between the recent experimental value for $A_{FB}^{b}(R_{b})$ and the standard model(SM) prediction, we examine the effect of new physics(NP) on the $Zb \bar{b}$ couplings $g_L^b$ and $g_R^b$. First we focus our attention on the dynamical models. Then, using effective lagrangean techniques, we discuss the corrections of NP to $g_L^b$ and $g_R^b$. We find some kinds of NP might explain the recently experimental data about $R_b$ and $A_{FB}^b$. However, the free parameters of these kinds of NP must be severely constrained. |
1304.2433 | David Weir | Mark Hindmarsh, Stephan J. Huber, Kari Rummukainen, David J. Weir | Gravitational waves from the sound of a first order phase transition | 5 pages, 4 figures; v2: Old Fig. 1 removed for space, error corrected
in fluid velocity power spectra normalisation, discussion of source modelling
significantly expanded, references added, conclusions unchanged, published in
PRL | Phys. Rev. Lett. 112, 041301 (2014) | 10.1103/PhysRevLett.112.041301 | HIP-2013-07/TH | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We report on the first 3-dimensional numerical simulations of first-order
phase transitions in the early universe to include the cosmic fluid as well as
the scalar field order parameter. We calculate the gravitational wave (GW)
spectrum resulting from the nucleation, expansion and collision of bubbles of
the low-temperature phase, for phase transition strengths and bubble wall
velocities covering many cases of interest. We find that the compression waves
in the fluid continue to be a source of GWs long after the bubbles have merged,
a new effect not taken properly into account in previous modelling of the GW
source. For a wide range of models the main source of the GWs produced by a
phase transition is therefore the sound the bubbles make.
| [
{
"created": "Mon, 8 Apr 2013 23:42:59 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Jan 2014 15:44:48 GMT",
"version": "v2"
}
] | 2014-01-30 | [
[
"Hindmarsh",
"Mark",
""
],
[
"Huber",
"Stephan J.",
""
],
[
"Rummukainen",
"Kari",
""
],
[
"Weir",
"David J.",
""
]
] | We report on the first 3-dimensional numerical simulations of first-order phase transitions in the early universe to include the cosmic fluid as well as the scalar field order parameter. We calculate the gravitational wave (GW) spectrum resulting from the nucleation, expansion and collision of bubbles of the low-temperature phase, for phase transition strengths and bubble wall velocities covering many cases of interest. We find that the compression waves in the fluid continue to be a source of GWs long after the bubbles have merged, a new effect not taken properly into account in previous modelling of the GW source. For a wide range of models the main source of the GWs produced by a phase transition is therefore the sound the bubbles make. |
hep-ph/0601122 | Ansgar Denner | A.Denner, S.Dittmaier, M.Roth, L.H.Wieders | Electroweak Corrections to e+e- --> 4 fermions | 5 pages, LaTeX, 6 postscript figures, to appear in the proceedings of
the "7th International Symposium on Radiative Corrections (RADCOR05)", Shonan
Village, 2005 | Nucl.Phys.Proc.Suppl.157:68-72,2006 | 10.1016/j.nuclphysbps.2006.03.009 | PSI-PR-06-02 | hep-ph | null | The calculation of the full electroweak O(alpha) corrections to the
charged-current four-fermion production processes e+e- --> nu_tau tau+ mu-
anti-nu_mu, u anti-d mu- anti-nu_mu, and u anti-d s anti-c is briefly reviewed.
The calculation is performed using the complex-mass scheme for the gauge-boson
resonances. The evaluation of the occurring one-loop tensor integrals, which
include 5- and 6-point functions, requires new techniques. The effects of the
complete O(alpha) corrections to the total cross section and to the
production-angle distribution are discussed and compared to predictions based
on the double-pole approximation, revealing that the latter approximation is
not sufficient to fully exploit the potential of a future linear collider in an
analysis of W-boson pairs at high energies.
| [
{
"created": "Mon, 16 Jan 2006 16:06:31 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Denner",
"A.",
""
],
[
"Dittmaier",
"S.",
""
],
[
"Roth",
"M.",
""
],
[
"Wieders",
"L. H.",
""
]
] | The calculation of the full electroweak O(alpha) corrections to the charged-current four-fermion production processes e+e- --> nu_tau tau+ mu- anti-nu_mu, u anti-d mu- anti-nu_mu, and u anti-d s anti-c is briefly reviewed. The calculation is performed using the complex-mass scheme for the gauge-boson resonances. The evaluation of the occurring one-loop tensor integrals, which include 5- and 6-point functions, requires new techniques. The effects of the complete O(alpha) corrections to the total cross section and to the production-angle distribution are discussed and compared to predictions based on the double-pole approximation, revealing that the latter approximation is not sufficient to fully exploit the potential of a future linear collider in an analysis of W-boson pairs at high energies. |
2307.00728 | Stefan H\"oche | Benoit Assi and Stefan H\"oche | A new approach to QCD evolution in processes with massive partons | 17 pages, 5 figures | null | null | FERMILAB-PUB-23-336-T, MCNET-23-09 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We present an algorithm for massive parton evolution which is based on the
differentially accurate simulation of soft-gluon radiation by means of a
non-trivial azimuthal angle dependence of the splitting functions. The
kinematics mapping is chosen such as to to reflect the symmetry of the final
state in soft-gluon radiation and collinear splitting processes. We compute the
counterterms needed for a fully differential NLO matching and discuss the
analytic structure of the parton shower in the NLL limit. We implement the new
algorithm in the numerical code Alaric and present a first comparison to
experimental data.
| [
{
"created": "Mon, 3 Jul 2023 03:20:27 GMT",
"version": "v1"
}
] | 2023-07-04 | [
[
"Assi",
"Benoit",
""
],
[
"Höche",
"Stefan",
""
]
] | We present an algorithm for massive parton evolution which is based on the differentially accurate simulation of soft-gluon radiation by means of a non-trivial azimuthal angle dependence of the splitting functions. The kinematics mapping is chosen such as to to reflect the symmetry of the final state in soft-gluon radiation and collinear splitting processes. We compute the counterterms needed for a fully differential NLO matching and discuss the analytic structure of the parton shower in the NLL limit. We implement the new algorithm in the numerical code Alaric and present a first comparison to experimental data. |
hep-ph/9410244 | Mike Seymour | Michael H. Seymour (Lund University, Sweden) | A Simple Prescription for First Order Corrections to Quark Scattering
and Annihilation Processes | 19 pages, LU TP 94-13 | Nucl.Phys. B436 (1995) 443-460 | 10.1016/0550-3213(94)00554-R | null | hep-ph | null | We formulate the first order corrections to processes involving the
scattering or annihilation of quarks in a form in which the QCD and electroweak
parts are exactly factorised. This allows for a straightforward physical
interpretation of effects such as lepton-hadron correlations, and a simpler
Monte Carlo treatment. The postscript file for this paper can also be obtained
by anonymous ftp from thep.lu.se, in the file pub/Preprints/lu_tp_94_13.ps
| [
{
"created": "Fri, 7 Oct 1994 13:30:49 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Seymour",
"Michael H.",
"",
"Lund University, Sweden"
]
] | We formulate the first order corrections to processes involving the scattering or annihilation of quarks in a form in which the QCD and electroweak parts are exactly factorised. This allows for a straightforward physical interpretation of effects such as lepton-hadron correlations, and a simpler Monte Carlo treatment. The postscript file for this paper can also be obtained by anonymous ftp from thep.lu.se, in the file pub/Preprints/lu_tp_94_13.ps |
1409.6704 | Jos\'e Daniel Madrigal | Martin Hentschinski, Jos\'e Daniel Madrigal Mart\'inez, Beatrice
Murdaca and Agust\'in Sabio Vera | The Gluon-Induced Mueller-Tang Jet Impact Factor at Next-to-Leading
Order | 32 pages, many figures | Nucl.Phys. B889 (2014) 549-579 | 10.1016/j.nuclphysb.2014.10.026 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We complete the computation of the Mueller-Tang jet impact factor at
next-to-leading order (NLO) initiated in arXiv:1406.5625 and presented in
arXiv:1404.2937 by computing the real corrections associated to gluons in the
initial state making use of Lipatov's effective action. NLO corrections for
this effective vertex are an important ingredient for a reliable description of
large rapidity gap phenomenology within the BFKL approach.
| [
{
"created": "Tue, 23 Sep 2014 19:19:51 GMT",
"version": "v1"
}
] | 2014-11-11 | [
[
"Hentschinski",
"Martin",
""
],
[
"Martínez",
"José Daniel Madrigal",
""
],
[
"Murdaca",
"Beatrice",
""
],
[
"Vera",
"Agustín Sabio",
""
]
] | We complete the computation of the Mueller-Tang jet impact factor at next-to-leading order (NLO) initiated in arXiv:1406.5625 and presented in arXiv:1404.2937 by computing the real corrections associated to gluons in the initial state making use of Lipatov's effective action. NLO corrections for this effective vertex are an important ingredient for a reliable description of large rapidity gap phenomenology within the BFKL approach. |
1407.6588 | Wan-Il Park | Seungwon Baek, P. Ko, Wan-Il Park | Local $Z_2$ scalar dark matter model confronting galactic ${\mathrm
GeV}$-scale $\gamma$-ray | matched to journal version | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a scalar dark matter (DM) model where DM ($X_I$) is stabilized by
a local $Z_2$ symmetry originating from a spontaneously broken local dark
$U(1)_X$. Compared with the usual scalar DM with a global $Z_2$ symmetry, the
local $Z_2$ model possesses three new extra fields, dark photon $Z^{'}$, dark
Higgs $\phi$ and the excited partner of scalar DM ($X_R$), with the kinetic
mixing and Higgs portal interactions dictated by local dark gauge invariance.
The resulting model can accommodate thermal relic density of scalar DM without
conflict with the invisible Higgs branching ratio and the bounds from DM direct
detections, thanks to the newly opened channels, $X_I X_I \rightarrow Z^{'}
Z^{'}, \phi\phi$. In particular, due to the new particles, the ${\rm GeV}$
scale $\gamma$-ray excess from the Galactic Center (GC) can be originated from
the decay of dark Higgs boson which is produced in DM annihilations.
| [
{
"created": "Thu, 24 Jul 2014 14:12:26 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Jan 2015 19:42:51 GMT",
"version": "v2"
},
{
"created": "Tue, 9 Jun 2015 19:58:56 GMT",
"version": "v3"
}
] | 2015-06-10 | [
[
"Baek",
"Seungwon",
""
],
[
"Ko",
"P.",
""
],
[
"Park",
"Wan-Il",
""
]
] | We present a scalar dark matter (DM) model where DM ($X_I$) is stabilized by a local $Z_2$ symmetry originating from a spontaneously broken local dark $U(1)_X$. Compared with the usual scalar DM with a global $Z_2$ symmetry, the local $Z_2$ model possesses three new extra fields, dark photon $Z^{'}$, dark Higgs $\phi$ and the excited partner of scalar DM ($X_R$), with the kinetic mixing and Higgs portal interactions dictated by local dark gauge invariance. The resulting model can accommodate thermal relic density of scalar DM without conflict with the invisible Higgs branching ratio and the bounds from DM direct detections, thanks to the newly opened channels, $X_I X_I \rightarrow Z^{'} Z^{'}, \phi\phi$. In particular, due to the new particles, the ${\rm GeV}$ scale $\gamma$-ray excess from the Galactic Center (GC) can be originated from the decay of dark Higgs boson which is produced in DM annihilations. |
2001.08550 | Antonio Costantini | Antonio Costantini, Margherita Ghezzi and Giovanni Marco Pruna | Theoretical constraints on the Higgs potential of the general $331$
model | 8 pages (two columns), accepted for publication in Physics Letters B | null | 10.1016/j.physletb.2020.135638 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This article reviews the theoretical constraints on the scalar potential of a
general extension of the Standard Model that encompasses a $SU(3)_c\times
SU(3)_L\times U(1)_X$ gauge symmetry. In this respect, the
boundedness-from-below is analysed to identify the correct criteria for
obtaining the physical minima of the Higgs parameter space. Furthermore,
perturbativity and unitarity bounds are discussed in light of the exact
diagonalisation of the scalar fields. This study represents a framework for
fast numerical checks on specific $331$ Model benchmarks that are relevant for
future collider searches.
| [
{
"created": "Wed, 22 Jan 2020 14:05:07 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Jul 2020 18:00:10 GMT",
"version": "v2"
}
] | 2020-07-29 | [
[
"Costantini",
"Antonio",
""
],
[
"Ghezzi",
"Margherita",
""
],
[
"Pruna",
"Giovanni Marco",
""
]
] | This article reviews the theoretical constraints on the scalar potential of a general extension of the Standard Model that encompasses a $SU(3)_c\times SU(3)_L\times U(1)_X$ gauge symmetry. In this respect, the boundedness-from-below is analysed to identify the correct criteria for obtaining the physical minima of the Higgs parameter space. Furthermore, perturbativity and unitarity bounds are discussed in light of the exact diagonalisation of the scalar fields. This study represents a framework for fast numerical checks on specific $331$ Model benchmarks that are relevant for future collider searches. |
hep-ph/9805335 | Konstantin Chetyrkin | K. G. Chetyrkin, J.H. K\"uhn and A.A. Pivovarov | Determining the Strange Quark Mass in Cabibbo Suppressed Tau Lepton
Decays | 26 pages, LaTeX, no figures | Nucl.Phys.B533:473-493,1998 | 10.1016/S0550-3213(98)00511-2 | null | hep-ph | null | In this work radiative corrections in the total hadronic decay rate of the
tau-lepton and some moments of its differential distributions are studied
employing perturbative QCD and the operator product expansion. We calculate
quadratic quark mass corrections in the strange mass to the decay rate ratio
R_tau to the order O(\alpha_s^3 m^2) and find that they contribute appreciably
to the Cabibbo suppressed decay modes of the tau-lepton. Using the results of a
recent experimental analysis, we obtain m_s(1 GeV) = 200 \pm 40_exp \pm 30_th
MeV.
| [
{
"created": "Fri, 15 May 1998 10:31:37 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Chetyrkin",
"K. G.",
""
],
[
"Kühn",
"J. H.",
""
],
[
"Pivovarov",
"A. A.",
""
]
] | In this work radiative corrections in the total hadronic decay rate of the tau-lepton and some moments of its differential distributions are studied employing perturbative QCD and the operator product expansion. We calculate quadratic quark mass corrections in the strange mass to the decay rate ratio R_tau to the order O(\alpha_s^3 m^2) and find that they contribute appreciably to the Cabibbo suppressed decay modes of the tau-lepton. Using the results of a recent experimental analysis, we obtain m_s(1 GeV) = 200 \pm 40_exp \pm 30_th MeV. |
2109.04157 | Hiroshi Okada | Takaaki Nomura, Hiroshi Okada | Linear seesaw model with a modular $S_4$ flavor symmetry | 21 pages, two tables, three figures; version accepted for publication
in Chinese Physics C | null | 10.1088/1674-1137/ac4975 | CTP-SCU/2021029, APCTP Pre2020 - 020 | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | We discuss a linear seesaw model with as minimum field content as possible,
introducing a modular $S_4$ with the help of gauged $U(1)_{B-L}$ symmetries.
Due to rank two neutrino mass matrix, we have a vanishing neutrino mass
eigenvalue, and only the normal mass hierarchy of neutrinos is favored through
the modular $S_4$ symmetry. In our numerical $\Delta \chi^2$ analysis, we
especially find rather sharp prediction on sum of neutrino masses to be around
$60$ meV in addition to the other predictions.
| [
{
"created": "Thu, 9 Sep 2021 10:37:43 GMT",
"version": "v1"
},
{
"created": "Fri, 31 Dec 2021 08:02:13 GMT",
"version": "v2"
}
] | 2022-05-04 | [
[
"Nomura",
"Takaaki",
""
],
[
"Okada",
"Hiroshi",
""
]
] | We discuss a linear seesaw model with as minimum field content as possible, introducing a modular $S_4$ with the help of gauged $U(1)_{B-L}$ symmetries. Due to rank two neutrino mass matrix, we have a vanishing neutrino mass eigenvalue, and only the normal mass hierarchy of neutrinos is favored through the modular $S_4$ symmetry. In our numerical $\Delta \chi^2$ analysis, we especially find rather sharp prediction on sum of neutrino masses to be around $60$ meV in addition to the other predictions. |
1611.07107 | Jun He | Jun He | $\bar{D}\Sigma^*_c$ and $\bar{D}^*\Sigma_c$ interactions and LHCb
pentaquarks | Talk given at the 14th International Conference on Meson-Nucleon
Physics and the Structure of the Nucleon (MENU2016), Kyoto, July 2016 | null | 10.7566/JPSCP.13.020045 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently, LHCb collaboration reported the observation of two hidden-charmed
resonances $P_c(4380)$ and $P_c(4450)$ consistent with hidden-charmed
pentaquarks. We perform a dynamical investigation about the
$\bar{D}\Sigma_c^*(2520)$ and $\bar{D}^*\Sigma_c(2455)$ interactions which are
described by the meson exchanges in a quasipotential Bethe-Salpeter equation
approach. Two poles around $4450$ and $4390$ MeV are produced from the
$\bar{D}^*\Sigma_c(2455)$ interaction with spin parities $3/2^-$ and $5/2^+$,
respectively. The peak for $5/2^+$ state has a comparable hight as that of
$3/2^-$ state in the $J/\psi p$ invariant mass spectrum. Another bound state
with spin-parity $J^P=3/2^-$ is produced from the $\bar{D}\Sigma^*_c(2520)$
interaction. Such results suggest that the narrower LHCb pentaquark $P_c(4450)$
can be well interpreted as a $5/2^+$ $\bar{D}^*\Sigma_c(2455)$ molecular state
while the $P_c(4380)$ is a $3/2^-$ $\bar{D}^*\Sigma_c(2455)$ molecular state
mixed with other secondary origins.
| [
{
"created": "Tue, 22 Nov 2016 00:04:27 GMT",
"version": "v1"
}
] | 2017-03-08 | [
[
"He",
"Jun",
""
]
] | Recently, LHCb collaboration reported the observation of two hidden-charmed resonances $P_c(4380)$ and $P_c(4450)$ consistent with hidden-charmed pentaquarks. We perform a dynamical investigation about the $\bar{D}\Sigma_c^*(2520)$ and $\bar{D}^*\Sigma_c(2455)$ interactions which are described by the meson exchanges in a quasipotential Bethe-Salpeter equation approach. Two poles around $4450$ and $4390$ MeV are produced from the $\bar{D}^*\Sigma_c(2455)$ interaction with spin parities $3/2^-$ and $5/2^+$, respectively. The peak for $5/2^+$ state has a comparable hight as that of $3/2^-$ state in the $J/\psi p$ invariant mass spectrum. Another bound state with spin-parity $J^P=3/2^-$ is produced from the $\bar{D}\Sigma^*_c(2520)$ interaction. Such results suggest that the narrower LHCb pentaquark $P_c(4450)$ can be well interpreted as a $5/2^+$ $\bar{D}^*\Sigma_c(2455)$ molecular state while the $P_c(4380)$ is a $3/2^-$ $\bar{D}^*\Sigma_c(2455)$ molecular state mixed with other secondary origins. |
2407.07986 | Kanat Nurlan | M.K. Volkov, A.A. Pivovarov, K. Nurlan | Description of the processes $e^+ e^- \to \pi^+ \pi^-$ and $\tau^- \to
\pi^- \pi^0 \nu_\tau$ in the NJL model with value of the vector coupling
constant $ g_{\rho} = 6$ | 10 pages, 9 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that the processes $e^+ e^- \to \pi^+ \pi^-$ and $\tau^- \to
\pi^- \pi^0 \nu_\tau$ can be described in a unified approach in satisfactory
agreement with experiment using the vector coupling constant $g_{\rho} = 6$. In
this case, in addition to quark loops, it is also necessary to take into
account meson loops corresponding to the next order in $1/N_c$. These loops
must be taken into account when describing the $\gamma (W) \to \rho$
transition, as well as in interaction of mesons in the final state.
| [
{
"created": "Wed, 10 Jul 2024 18:38:03 GMT",
"version": "v1"
}
] | 2024-07-12 | [
[
"Volkov",
"M. K.",
""
],
[
"Pivovarov",
"A. A.",
""
],
[
"Nurlan",
"K.",
""
]
] | It is shown that the processes $e^+ e^- \to \pi^+ \pi^-$ and $\tau^- \to \pi^- \pi^0 \nu_\tau$ can be described in a unified approach in satisfactory agreement with experiment using the vector coupling constant $g_{\rho} = 6$. In this case, in addition to quark loops, it is also necessary to take into account meson loops corresponding to the next order in $1/N_c$. These loops must be taken into account when describing the $\gamma (W) \to \rho$ transition, as well as in interaction of mesons in the final state. |
hep-ph/0009283 | Roberto Florean | F. Benatti and R. Floreanini | Effective dissipative dynamics for polarized photons | 15 pages, plain-TeX, no figures | Phys.Rev.D62:125009,2000 | 10.1103/PhysRevD.62.125009 | null | hep-ph hep-th quant-ph | null | In the framework of open quantum systems, the propagation of polarized
photons can be effectively described using quantum dynamical semigroups. These
extended time-evolutions induce irreversibility and dissipation. Planned, high
sensitive experiments, both in the laboratory and in space, will be able to put
stringent bounds on these non-standard effects.
| [
{
"created": "Mon, 25 Sep 2000 11:41:01 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Benatti",
"F.",
""
],
[
"Floreanini",
"R.",
""
]
] | In the framework of open quantum systems, the propagation of polarized photons can be effectively described using quantum dynamical semigroups. These extended time-evolutions induce irreversibility and dissipation. Planned, high sensitive experiments, both in the laboratory and in space, will be able to put stringent bounds on these non-standard effects. |
hep-ph/0506059 | Ryszard Manka | I. Bednarek and R. Manka (University of Silesia, Poland) | The influence of strength of hyperon-hyperon interactions on neutron
star properties | 18 pages, 22 figures, accepted to be published in Journal of Physics
G: Nuclear and Particle Physics | J.Phys.G31:1009-1024,2005 | 10.1088/0954-3899/31/9/003 | null | hep-ph astro-ph nucl-th | null | An equation of state of neutron star matter with strange baryons has been
obtained. The effects of the strength of hyperon-hyperon interactions on the
equations of state constructed for the chosen parameter sets have been
analyzed. Numerous neutron star models show that the appearance of hyperons is
connected with the increasing density in neutron star interiors. The performed
calculations have indicated that the change of the hyperon-hyperon coupling
constants affects the chemical composition of a neutron star. The obtained
numerical hyperon star models exclude large population of strange baryons in
the star interior.
| [
{
"created": "Mon, 6 Jun 2005 20:25:48 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Bednarek",
"I.",
"",
"University of Silesia, Poland"
],
[
"Manka",
"R.",
"",
"University of Silesia, Poland"
]
] | An equation of state of neutron star matter with strange baryons has been obtained. The effects of the strength of hyperon-hyperon interactions on the equations of state constructed for the chosen parameter sets have been analyzed. Numerous neutron star models show that the appearance of hyperons is connected with the increasing density in neutron star interiors. The performed calculations have indicated that the change of the hyperon-hyperon coupling constants affects the chemical composition of a neutron star. The obtained numerical hyperon star models exclude large population of strange baryons in the star interior. |
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