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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/9905531 | Daniel de Florian | Daniel de Florian (ETH, Zurich) | Polarized Fragmentation Functions | Talk at the Electron Polarized Ion Collider Workshop (EPIC99), at
IUCF, Bloomington, IA, April 1999, 15 pp, 6 figs | null | 10.1063/1.1345348 | ETH-TH/99-17 | hep-ph | null | In this talk I present a review on the theoretical status of polarized
fragmentation functions and the prospects for conceivable future semi-inclusive
deep-inelastic scattering and proton-proton collision experiments to measure
them.
| [
{
"created": "Fri, 28 May 1999 08:39:43 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"de Florian",
"Daniel",
"",
"ETH, Zurich"
]
] | In this talk I present a review on the theoretical status of polarized fragmentation functions and the prospects for conceivable future semi-inclusive deep-inelastic scattering and proton-proton collision experiments to measure them. |
hep-ph/0009128 | Werner Porod | M. Hirsch, W. Porod, J. Romao and J.W.F. Valle | Broken R Parity, Neutrino Anomalies and Collider Tests | LaTex, 4 pages, 5 Figures included, contribution to ICHEP2000, needs
ws-p10x7.cls (included) | null | null | IFIC/00-53 | hep-ph | null | The solar and atmospheric neutrino anomalies constitute the only solid and
most remarkable evidence for physics beyond the Standard Model, indicating that
the lepton mixing matrix is fundamentally distinct from that describing the
quarks. Here I will report on how supersymmetry with spontaneously or
bilinearly broken R Parity provides a predictive theory for neutrino mass and
mixing which leads to a solution of neutrino anomalies which can be clearly
tested at high energy accelerators.
| [
{
"created": "Mon, 11 Sep 2000 15:51:28 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Hirsch",
"M.",
""
],
[
"Porod",
"W.",
""
],
[
"Romao",
"J.",
""
],
[
"Valle",
"J. W. F.",
""
]
] | The solar and atmospheric neutrino anomalies constitute the only solid and most remarkable evidence for physics beyond the Standard Model, indicating that the lepton mixing matrix is fundamentally distinct from that describing the quarks. Here I will report on how supersymmetry with spontaneously or bilinearly broken R Parity provides a predictive theory for neutrino mass and mixing which leads to a solution of neutrino anomalies which can be clearly tested at high energy accelerators. |
2108.12810 | Rui Santos | Felipe F. Freitas, Gabriel Louren\c{c}o, Ant\'onio P. Morais, Andr\'e
Nunes, Jo\~ao Ol\'ivia, Roman Pasechnik, Rui Santos, Jo\~ao Viana | Impact of SM parameters and of the vacua of the Higgs potential in
gravitational waves detection | 28 pages, 13 figures | null | 10.1088/1475-7516/2022/03/046 | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | In this work we discuss two different phases of a complex singlet extension
of the Standard Model (SM) together with an extension that also includes new
fermion fields, in particular, a Majoron model equipped with an inverse seesaw
mechanism. All considered scenarios contain a global $\mathrm{U}(1)$ symmetry
and allow for first-order phase transitions while only two of them are strong
enough to favour the detection of primordial gravitational waves (GWs) in
planned experiments such as LISA. In particular, this is shown to be possible
in the singlet extension with a non vanishing real VEV at zero temperature and
also in the model with extra fermions. In the singlet extension with no
additional fermions, the detection of GWs strongly depends on the
$\mathrm{U}(1)$ symmetry breaking pattern of the scalar potential at zero
temperature. We study for the first time the impact of the precision in the
determination of the SM parameters on the strength of the GWs spectrum. It
turns out that the variation of the SM parameters such as the Higgs boson mass
and top quark Yukawa coupling in their allowed experimental ranges has a
notable impact on GWs detectability prospects.
| [
{
"created": "Sun, 29 Aug 2021 10:23:30 GMT",
"version": "v1"
},
{
"created": "Fri, 11 Mar 2022 10:13:58 GMT",
"version": "v2"
},
{
"created": "Thu, 17 Mar 2022 07:49:07 GMT",
"version": "v3"
}
] | 2022-03-30 | [
[
"Freitas",
"Felipe F.",
""
],
[
"Lourenço",
"Gabriel",
""
],
[
"Morais",
"António P.",
""
],
[
"Nunes",
"André",
""
],
[
"Olívia",
"João",
""
],
[
"Pasechnik",
"Roman",
""
],
[
"Santos",
"Rui",
""
],
[
"Viana",
"João",
""
]
] | In this work we discuss two different phases of a complex singlet extension of the Standard Model (SM) together with an extension that also includes new fermion fields, in particular, a Majoron model equipped with an inverse seesaw mechanism. All considered scenarios contain a global $\mathrm{U}(1)$ symmetry and allow for first-order phase transitions while only two of them are strong enough to favour the detection of primordial gravitational waves (GWs) in planned experiments such as LISA. In particular, this is shown to be possible in the singlet extension with a non vanishing real VEV at zero temperature and also in the model with extra fermions. In the singlet extension with no additional fermions, the detection of GWs strongly depends on the $\mathrm{U}(1)$ symmetry breaking pattern of the scalar potential at zero temperature. We study for the first time the impact of the precision in the determination of the SM parameters on the strength of the GWs spectrum. It turns out that the variation of the SM parameters such as the Higgs boson mass and top quark Yukawa coupling in their allowed experimental ranges has a notable impact on GWs detectability prospects. |
0901.1949 | T. Lappi | T. Lappi | Initial conditions of heavy ion collisions and small x | 6 pages, 6 figures, using elsart1p.sty. Talk at International
Conference on Particles And Nuclei (PANIC08), Eilat, Israel, November 2008 | Nucl.Phys.A827:365c-370c,2009 | 10.1016/j.nuclphysa.2009.05.079 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Color Glass Condensate (CGC), describing the physics of the nonlinear
gluonic interactions of QCD at high energy, provides a consistent
first-principles framework to understand the initial conditions of heavy ion
collisions. This talk reviews some aspects of the initial conditions at RHIC
and discusses implications for LHC heavy ion phenomenology. The CGC provides a
way compute bulk particle production and understand recent experimental
observations of long range rapidity correlations in terms of the classical
glasma field in the early stages of the collision.
| [
{
"created": "Wed, 14 Jan 2009 09:15:44 GMT",
"version": "v1"
}
] | 2010-02-25 | [
[
"Lappi",
"T.",
""
]
] | The Color Glass Condensate (CGC), describing the physics of the nonlinear gluonic interactions of QCD at high energy, provides a consistent first-principles framework to understand the initial conditions of heavy ion collisions. This talk reviews some aspects of the initial conditions at RHIC and discusses implications for LHC heavy ion phenomenology. The CGC provides a way compute bulk particle production and understand recent experimental observations of long range rapidity correlations in terms of the classical glasma field in the early stages of the collision. |
hep-ph/9211333 | Thomas Mannel | Wolfgang Kilian and Thomas Mannel | QCD Corrected $1/m_b$ Contributions to $B\bbar$--Mixixng | 16 Pages, LaTeX, 3 figures in separate uuencoded Postscript file,
Darmstadt report IKDA 92 / 36 | Phys.Lett. B301 (1993) 382-392 | 10.1016/0370-2693(93)91167-L | null | hep-ph | null | We calculate the QCD corrected effective Hamiltonian for $B\bbar$--Mixing in
heavy quark effective theory including corrections of the order $\Lambda_{QCD}
/ m_b$. The matrix elements of the subleading operators are estimated using the
vacuum insertion assumption. We show that the major part of the subleading
corrections may be absorbed into the heavy meson decay constant $f_B$; the
remaining corrections are only due to QCD effects and give an enhancement of
$\Delta M$ of 5\%.
| [
{
"created": "Mon, 30 Nov 1992 15:49:47 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Kilian",
"Wolfgang",
""
],
[
"Mannel",
"Thomas",
""
]
] | We calculate the QCD corrected effective Hamiltonian for $B\bbar$--Mixing in heavy quark effective theory including corrections of the order $\Lambda_{QCD} / m_b$. The matrix elements of the subleading operators are estimated using the vacuum insertion assumption. We show that the major part of the subleading corrections may be absorbed into the heavy meson decay constant $f_B$; the remaining corrections are only due to QCD effects and give an enhancement of $\Delta M$ of 5\%. |
0906.5013 | Spencer Chang | Spencer Chang and Markus A. Luty | Displaced Dark Matter at Colliders | 5 pages, 1 figure, revtex | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Models in which the dark matter is very weakly coupled to the observable
sector may explain the observed dark matter density, either as a "superWIMP" or
as "asymmetric dark matter." Both types of models predict displaced vertices at
colliders, with a rich variety of possible phenomenology. We classify the cases
in which the decays can naturally occur inside particle detectors at the LHC,
with particular focus on the nontrivial scenarios where the decaying particle
is invisible. Identification of the position and timing of these invisible
displaced vertices significantly improves the prospects of reconstructing the
new physics in models such as supersymmetry. In many cases, reconstruction of
the visible products of the displaced decay can determine the dark matter mass,
allowing the dark matter density to be predicted from collider data.
| [
{
"created": "Mon, 29 Jun 2009 19:13:40 GMT",
"version": "v1"
}
] | 2009-06-30 | [
[
"Chang",
"Spencer",
""
],
[
"Luty",
"Markus A.",
""
]
] | Models in which the dark matter is very weakly coupled to the observable sector may explain the observed dark matter density, either as a "superWIMP" or as "asymmetric dark matter." Both types of models predict displaced vertices at colliders, with a rich variety of possible phenomenology. We classify the cases in which the decays can naturally occur inside particle detectors at the LHC, with particular focus on the nontrivial scenarios where the decaying particle is invisible. Identification of the position and timing of these invisible displaced vertices significantly improves the prospects of reconstructing the new physics in models such as supersymmetry. In many cases, reconstruction of the visible products of the displaced decay can determine the dark matter mass, allowing the dark matter density to be predicted from collider data. |
hep-ph/0701009 | Kuang-Ta Chao | Ying-Jia Gao, Yu-Jie Zhang, Kuang-Ta Chao | Radiative decays of bottomonia into charmonia and light mesons | null | null | null | null | hep-ph | null | In the framework of nonrelativistic QCD, we study the radiative decays of
bottomonia into charmonia, including $\Upsilon\to \chi_{cJ}\gamma$,
$\Upsilon\to \eta_c\gamma$, $\eta_b\to J/\psi\gamma$, and $\chi_{bJ}\to
J/\psi\gamma$. We give predictions for their branching ratios with numerical
calculations. E.g., we predict the branching ratio for $\eta_b\to J/\psi\gamma$
is about $1\times 10^{-7}$. As a phenomenological model study, we further
extend our calculation to the radiative decays of bottomonia into light mesons
by assuming the $f_2(1270)$, $f_2'(1525)$ and other light mesons to be
described by nonrelativistic $q\bar q ~(q=u,d,s)$ bound states with constituent
quark masses. The calculated branching ratios for $\Upsilon\to f_2(1270)\gamma$
and $\Upsilon\to f_2'(1525)\gamma$ are roughly consistent with the CLEO data.
Comparisons with radiative decays of charmonium into light mesons such as
$J/\psi\to f_2(1270)\gamma$ are also given. In all calculations the QED
contributions are taken into account and found to be significant in some
processes.
| [
{
"created": "Mon, 1 Jan 2007 04:50:16 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Jan 2007 21:03:52 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Gao",
"Ying-Jia",
""
],
[
"Zhang",
"Yu-Jie",
""
],
[
"Chao",
"Kuang-Ta",
""
]
] | In the framework of nonrelativistic QCD, we study the radiative decays of bottomonia into charmonia, including $\Upsilon\to \chi_{cJ}\gamma$, $\Upsilon\to \eta_c\gamma$, $\eta_b\to J/\psi\gamma$, and $\chi_{bJ}\to J/\psi\gamma$. We give predictions for their branching ratios with numerical calculations. E.g., we predict the branching ratio for $\eta_b\to J/\psi\gamma$ is about $1\times 10^{-7}$. As a phenomenological model study, we further extend our calculation to the radiative decays of bottomonia into light mesons by assuming the $f_2(1270)$, $f_2'(1525)$ and other light mesons to be described by nonrelativistic $q\bar q ~(q=u,d,s)$ bound states with constituent quark masses. The calculated branching ratios for $\Upsilon\to f_2(1270)\gamma$ and $\Upsilon\to f_2'(1525)\gamma$ are roughly consistent with the CLEO data. Comparisons with radiative decays of charmonium into light mesons such as $J/\psi\to f_2(1270)\gamma$ are also given. In all calculations the QED contributions are taken into account and found to be significant in some processes. |
hep-ph/0408103 | Apostolos Pilaftsis | Apostolos Pilaftsis | Resonant \tau-Leptogenesis with Observable Lepton Number Violation | 4 ReVTeX pages, 1 eps figure, minor rewordings, to appear in Physical
Review Letters | Phys.Rev.Lett. 95 (2005) 081602 | 10.1103/PhysRevLett.95.081602 | null | hep-ph | null | We consider a minimal extension of the Standard Model with one singlet
neutrino per generation that can realize resonant leptogenesis at the
electroweak scale. In particular, the baryon asymmetry in the Universe can be
created by resonant lepton-to-baryon conversion of an individual lepton number,
for example that of the $\tau$-lepton. The solar and atmospheric neutrino data
can be explained by a simple CP-violating Yukawa texture. The model has several
testable phenomenological implications. Most interestingly, it predicts heavy
Majorana neutrinos at the sub-TeV scale, which can be probed at $e^+e^-$ linear
colliders, as well as $e$- and $\mu$-lepton-number-violating processes, such as
$0\nu\beta\beta$ decay and $\mu \to e\gamma$, with rates that are within reach
of experimental sensitivity.
| [
{
"created": "Mon, 9 Aug 2004 15:06:31 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Aug 2004 17:50:52 GMT",
"version": "v2"
},
{
"created": "Thu, 11 Aug 2005 14:10:15 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Pilaftsis",
"Apostolos",
""
]
] | We consider a minimal extension of the Standard Model with one singlet neutrino per generation that can realize resonant leptogenesis at the electroweak scale. In particular, the baryon asymmetry in the Universe can be created by resonant lepton-to-baryon conversion of an individual lepton number, for example that of the $\tau$-lepton. The solar and atmospheric neutrino data can be explained by a simple CP-violating Yukawa texture. The model has several testable phenomenological implications. Most interestingly, it predicts heavy Majorana neutrinos at the sub-TeV scale, which can be probed at $e^+e^-$ linear colliders, as well as $e$- and $\mu$-lepton-number-violating processes, such as $0\nu\beta\beta$ decay and $\mu \to e\gamma$, with rates that are within reach of experimental sensitivity. |
2208.05029 | Yizhuang Liu | Xiangdong Ji, Yizhuang Liu | Gravitational Tensor-Monopole Moment of Hydrogen Atom To Order ${\cal
O}(\alpha)$ | 22 pages, 9 figures. Typos corrected from v1 | null | null | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the gravitational tensor-monopole moment of the momentum-current
density $T^{ij}$ in the ground state of the hydrogen atom to order ${\cal
O}(\alpha)$ in quantum electrodynamics (QED). The result is \begin{align}
\tau_H/\tau_0 - 1 = \frac{4\alpha}{3\pi}\left(\ln\alpha^2-0.028\right)
\nonumber \end{align} where $\tau_0= \hbar^2/4m_e$ is the leading-order moment.
The physics of the next-to-leading-order correction is similar to that of the
famous Lamb shift for energy levels.
| [
{
"created": "Tue, 9 Aug 2022 20:18:23 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Mar 2023 21:32:17 GMT",
"version": "v2"
}
] | 2023-03-10 | [
[
"Ji",
"Xiangdong",
""
],
[
"Liu",
"Yizhuang",
""
]
] | We calculate the gravitational tensor-monopole moment of the momentum-current density $T^{ij}$ in the ground state of the hydrogen atom to order ${\cal O}(\alpha)$ in quantum electrodynamics (QED). The result is \begin{align} \tau_H/\tau_0 - 1 = \frac{4\alpha}{3\pi}\left(\ln\alpha^2-0.028\right) \nonumber \end{align} where $\tau_0= \hbar^2/4m_e$ is the leading-order moment. The physics of the next-to-leading-order correction is similar to that of the famous Lamb shift for energy levels. |
2307.08406 | Prabhupada Dixit | Prabhupada Dixit and Md. Nasim | Longitudinal flow decorrelation in heavy-ion collision at RHIC energies
using a multi-phase transport model | 5 pages, 5 figures | null | null | null | hep-ph hep-ex nucl-th | http://creativecommons.org/licenses/by-nc-nd/4.0/ | We present a comprehensive study on the longitudinal flow decorrelation in
heavy-ion collisions at the RHIC Beam Energy Scan (BES) energies, spanning from
$\sqrt{s_{NN}}$ = 11.5 to 200 GeV in Au+Au collisions, using the A Multi-Phase
Transport (AMPT) model. Our investigation entails measuring the second and
third order factorization ratios ($r_{2}$ and $r_{3}$) across all these
energies. We observed that the decorrelation is stronger at lower energies
compared to higher collision energies, with this energy dependence trend being
more prominent in $r_{3}$. Additionally, we analyze the contributions of
flow-plane and flow magnitude decorrelation to the overall decorrelation
phenomenon. Notably, our findings reveal that flow plane decorrelation exhibits
a dominant contribution compared to flow magnitude decorrelation. Moreover, we
incorporate a recently proposed observable, the four particle cumulant
($T_{2}$), which remains resilient to non-flow effects and exhibits sensitivity
to different decorrelation patterns. Through the measurement of $T_{2}$, we
consistently observe an S-shaped or torqued decorrelation across all energy
ranges.
| [
{
"created": "Mon, 17 Jul 2023 11:42:47 GMT",
"version": "v1"
}
] | 2023-07-18 | [
[
"Dixit",
"Prabhupada",
""
],
[
"Nasim",
"Md.",
""
]
] | We present a comprehensive study on the longitudinal flow decorrelation in heavy-ion collisions at the RHIC Beam Energy Scan (BES) energies, spanning from $\sqrt{s_{NN}}$ = 11.5 to 200 GeV in Au+Au collisions, using the A Multi-Phase Transport (AMPT) model. Our investigation entails measuring the second and third order factorization ratios ($r_{2}$ and $r_{3}$) across all these energies. We observed that the decorrelation is stronger at lower energies compared to higher collision energies, with this energy dependence trend being more prominent in $r_{3}$. Additionally, we analyze the contributions of flow-plane and flow magnitude decorrelation to the overall decorrelation phenomenon. Notably, our findings reveal that flow plane decorrelation exhibits a dominant contribution compared to flow magnitude decorrelation. Moreover, we incorporate a recently proposed observable, the four particle cumulant ($T_{2}$), which remains resilient to non-flow effects and exhibits sensitivity to different decorrelation patterns. Through the measurement of $T_{2}$, we consistently observe an S-shaped or torqued decorrelation across all energy ranges. |
1210.7588 | Vladimir Vechernin | Vladimir Vechernin | Forward-backward correlations between multiplicities in windows
separated in azimuth and rapidity | 25 pages, 6 figure. The results of calculations and the data at 2.76
TeV are added, Fig.5 and Table 1 are modified | Nuclear Physics A 939 (2015) 21-45 | 10.1016/j.nuclphysa.2015.03.009 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The forward-backward (FB) charged particle multiplicity correlations between
windows separated in rapidity and azimuth are analyzed using a model that
treats strings as independent identical emitters. Both the short-range (SR)
contribution, originating from the correlation between multiplicities produced
from a single source, and the long-range (LR) contribution, originating from
the fluctuation in the number of sources, are taken into account. The
dependencies of the FB correlation coefficient, $b$, on the windows' rapidity
and azimuthal acceptance and the gaps between these windows are studied and
compared with the preliminary data of ALICE. The analysis of these dependencies
effectively separates the contributions of two above mechanisms. It is also
demonstrated that traditional definitions of FB correlation coefficient $b$
have a strong nonlinear dependence on the acceptance of windows. Suitable
alternative observables for the future FB correlation studies are proposed. The
connection between $b$ and the two-particle correlation function, $C_2$, is
traced, as well as its connection to the untriggered di-hadron correlation
analysis. Using a model independent analysis, it is shown that measurement of
the FB multiplicity correlations between two small windows separated in
rapidity and azimuth fully determine the two-particle correlation function
$C_2$, even if the particle distribution in rapidity is not uniform.
| [
{
"created": "Mon, 29 Oct 2012 08:32:43 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Mar 2013 20:08:00 GMT",
"version": "v2"
},
{
"created": "Mon, 14 Jul 2014 12:37:29 GMT",
"version": "v3"
},
{
"created": "Tue, 21 Oct 2014 13:16:10 GMT",
"version": "v4"
},
{
"created": "Fri, 24 Oct 2014 08:52:58 GMT",
"version": "v5"
}
] | 2017-06-05 | [
[
"Vechernin",
"Vladimir",
""
]
] | The forward-backward (FB) charged particle multiplicity correlations between windows separated in rapidity and azimuth are analyzed using a model that treats strings as independent identical emitters. Both the short-range (SR) contribution, originating from the correlation between multiplicities produced from a single source, and the long-range (LR) contribution, originating from the fluctuation in the number of sources, are taken into account. The dependencies of the FB correlation coefficient, $b$, on the windows' rapidity and azimuthal acceptance and the gaps between these windows are studied and compared with the preliminary data of ALICE. The analysis of these dependencies effectively separates the contributions of two above mechanisms. It is also demonstrated that traditional definitions of FB correlation coefficient $b$ have a strong nonlinear dependence on the acceptance of windows. Suitable alternative observables for the future FB correlation studies are proposed. The connection between $b$ and the two-particle correlation function, $C_2$, is traced, as well as its connection to the untriggered di-hadron correlation analysis. Using a model independent analysis, it is shown that measurement of the FB multiplicity correlations between two small windows separated in rapidity and azimuth fully determine the two-particle correlation function $C_2$, even if the particle distribution in rapidity is not uniform. |
1305.3847 | Konstantin G. Savvidy | Yun Zhang and Konstantin Savvidy | Proton Compton scattering in a unified proton-Delta Model | 22 pages, 36 figures, pdflatex | Phys. Rev. C 88, 064614 (2013) | 10.1103/PhysRevC.88.064614 | NITS-PHY-2013002 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We develop a field-theoretic model for the description of proton Compton
scattering in which the proton and its excited state, the \Delta+ resonance,
are described as part of one multiplet with a single Rarita-Schwinger
wavefunction. In order to describe the phenomena observed, it is necessary to
incorporate both minimal and non-minimal couplings. The minimal coupling
reflects the fact that the \Delta+ is a charged particle, and in this model the
minimal coupling contributes also to the M1 magnetic transition via the \gamma
N\Delta vertex. The non-minimal couplings consist of five electromagnetic
form-factors, which are accessed at fixed and vanishing momentum-transfer
squared with real photons in Compton scattering experiments, therefore it is
possible to extract a rather well-determined set of optimal parameters which
reasonably well fit the data in the resonance region 140-450 MeV. The crucial
parameter which determines the \gamma N\Delta transition amplitude and
therefore the height of the resonance peak is equal to 3.66 +- 0.03, in units
of \mu_N. We find that this parameter also primarily determines the
contributions to magnetic polarizability in this model. In the low-energy
region up to 140 MeV, we separately fit the electric and magnetic
polarizabilities, while keeping the other parameters fixed and obtain values in
line with previous approaches. The basic model is then extended by
incorporating the sigma-meson channel with the currently favored parameters,
and the pion vertex corrections.
| [
{
"created": "Thu, 16 May 2013 15:53:04 GMT",
"version": "v1"
}
] | 2014-01-01 | [
[
"Zhang",
"Yun",
""
],
[
"Savvidy",
"Konstantin",
""
]
] | We develop a field-theoretic model for the description of proton Compton scattering in which the proton and its excited state, the \Delta+ resonance, are described as part of one multiplet with a single Rarita-Schwinger wavefunction. In order to describe the phenomena observed, it is necessary to incorporate both minimal and non-minimal couplings. The minimal coupling reflects the fact that the \Delta+ is a charged particle, and in this model the minimal coupling contributes also to the M1 magnetic transition via the \gamma N\Delta vertex. The non-minimal couplings consist of five electromagnetic form-factors, which are accessed at fixed and vanishing momentum-transfer squared with real photons in Compton scattering experiments, therefore it is possible to extract a rather well-determined set of optimal parameters which reasonably well fit the data in the resonance region 140-450 MeV. The crucial parameter which determines the \gamma N\Delta transition amplitude and therefore the height of the resonance peak is equal to 3.66 +- 0.03, in units of \mu_N. We find that this parameter also primarily determines the contributions to magnetic polarizability in this model. In the low-energy region up to 140 MeV, we separately fit the electric and magnetic polarizabilities, while keeping the other parameters fixed and obtain values in line with previous approaches. The basic model is then extended by incorporating the sigma-meson channel with the currently favored parameters, and the pion vertex corrections. |
hep-ph/0511165 | Alex Rivero E | Alejandro Rivero (EUPT, Universidad de Zaragoza) | GUT angle minimises $Z^0$ decay | 5 pages, 1 figure | null | null | null | hep-ph | null | The GUT value of Weinberg's angle is also the value that minimises the total
square matrix elements of $Z^0$ decay, independently of any GUT consideration,
and thus the one that maximises the neutrino branching ratio against total
width. We review the proof of this result and some related facts.
| [
{
"created": "Mon, 14 Nov 2005 13:52:46 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Rivero",
"Alejandro",
"",
"EUPT, Universidad de Zaragoza"
]
] | The GUT value of Weinberg's angle is also the value that minimises the total square matrix elements of $Z^0$ decay, independently of any GUT consideration, and thus the one that maximises the neutrino branching ratio against total width. We review the proof of this result and some related facts. |
0709.0784 | St\'ephane Munier | S. Munier (Ecole polytechnique, CPHT) | Connections between high energy QCD and statistical physics | 8 pages; To appear in the proceedings of 12th International
Conference on Elastic and Diffractive Scattering, DESY, Hamburg, Germany,
21-25 May 2007 | null | null | CPHT-PC-129.0907 | hep-ph | null | It has been proposed that the energy evolution of QCD amplitudes in the
high-energy regime falls in the universality class of reaction-diffusion
processes. We review the arguments for this correspondence, and we explain how
it enables one to compute analytically asymptotic features of QCD amplitudes.
| [
{
"created": "Thu, 6 Sep 2007 15:14:35 GMT",
"version": "v1"
}
] | 2007-09-07 | [
[
"Munier",
"S.",
"",
"Ecole polytechnique, CPHT"
]
] | It has been proposed that the energy evolution of QCD amplitudes in the high-energy regime falls in the universality class of reaction-diffusion processes. We review the arguments for this correspondence, and we explain how it enables one to compute analytically asymptotic features of QCD amplitudes. |
hep-ph/0101110 | Osamu Kiriyama | O. Kiriyama, M. Maruyama, and F. Takagi | Current quark mass effects on chiral phase transition of QCD in the
improved ladder approximation | 19 pages, 13 figures | Phys.Rev. D63 (2001) 116009 | 10.1103/PhysRevD.63.116009 | null | hep-ph | null | Current quark mass effects on the chiral phase transition of QCD is studied
in the improved ladder approximation. An infrared behavior of the gluon
propagator is modified in terms of an effective running coupling. The analysis
is based on a composite operator formalism and a variational approach. We use
the Schwinger-Dyson equation to give a ``normalization condition'' for the
Cornwall-Jackiw-Tomboulis effective potential and to isolate the ultraviolet
divergence which appears in an expression for the quark-antiquark condensate.
We study the current quark mass effects on the order parameter at zero
temperature and density. We then calculate the effective potential at finite
temperature and density and investigate the current quark mass effects on the
chiral phase transition. We find a smooth crossover for $T>0$, $\mu=0$ and a
first-order phase transition for $\mu>0$, T=0. Critical exponents are also
studied and our model gives the classical mean-field values. We also study the
temperature dependence of masses of scalar and pseudoscalar bosons. A critical
end point in the $T$-$\mu$ plane is found at $T \sim 100$ MeV, $\mu \sim 300$
MeV.
| [
{
"created": "Thu, 11 Jan 2001 07:18:58 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Mar 2001 07:41:13 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Kiriyama",
"O.",
""
],
[
"Maruyama",
"M.",
""
],
[
"Takagi",
"F.",
""
]
] | Current quark mass effects on the chiral phase transition of QCD is studied in the improved ladder approximation. An infrared behavior of the gluon propagator is modified in terms of an effective running coupling. The analysis is based on a composite operator formalism and a variational approach. We use the Schwinger-Dyson equation to give a ``normalization condition'' for the Cornwall-Jackiw-Tomboulis effective potential and to isolate the ultraviolet divergence which appears in an expression for the quark-antiquark condensate. We study the current quark mass effects on the order parameter at zero temperature and density. We then calculate the effective potential at finite temperature and density and investigate the current quark mass effects on the chiral phase transition. We find a smooth crossover for $T>0$, $\mu=0$ and a first-order phase transition for $\mu>0$, T=0. Critical exponents are also studied and our model gives the classical mean-field values. We also study the temperature dependence of masses of scalar and pseudoscalar bosons. A critical end point in the $T$-$\mu$ plane is found at $T \sim 100$ MeV, $\mu \sim 300$ MeV. |
2111.00616 | Christopher Gorham Lester | Christopher G. Lester and Rupert Tombs | Using unsupervised learning to detect broken symmetries, with relevance
to searches for parity violation in nature. (Previously: "Stressed GANs snag
desserts") | 10 pages, 4 figures. v2: updated arXiv numbers in bib. v3: typo
fixes, v4: adding workaround to provide access to sister paper (Ref [7])
following arXiv moderation problems. v5 removed bib workaround and added
author affiliations. v6: typo fixes. v7: better separation of proposal vs
illustration. v8: referee comments | Transactions on Machine Learning Research, 2022 | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Testing whether data breaks symmetries of interest can be important to many
fields. This paper describes a simple way that machine learning algorithms
(whose outputs have been appropriately symmetrised) can be used to detect
symmetry breaking. The original motivation for the paper was an important
question in Particle Physics: "Is parity violated at the LHC in some way that
no-one has anticipated?" and so we illustrate the main idea with an example
strongly related to that question. However, in order that the key ideas be
accessible to readers who are not particle physicists but who are interesting
in symmetry breaking, we choose to illustrate the method/approach with a 'toy'
example which places a simple discrete source of symmetry breaking (the
handedness of human handwriting) within a idealised particle-physics-like
context. Readers interested in seeing extensions to continuous symmetries,
non-ideal environments or more realistic particle-physics contexts are provided
with links to separate papers which delve into such details.
| [
{
"created": "Sun, 31 Oct 2021 23:06:37 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Nov 2021 01:26:28 GMT",
"version": "v2"
},
{
"created": "Wed, 3 Nov 2021 13:01:05 GMT",
"version": "v3"
},
{
"created": "Thu, 4 Nov 2021 08:46:07 GMT",
"version": "v4"
},
{
"created": "Thu, 11 Nov 2021 23:53:09 GMT",
"version": "v5"
},
{
"created": "Wed, 24 Nov 2021 13:05:54 GMT",
"version": "v6"
},
{
"created": "Sun, 19 Jun 2022 13:40:26 GMT",
"version": "v7"
},
{
"created": "Sat, 15 Oct 2022 01:07:24 GMT",
"version": "v8"
}
] | 2022-10-21 | [
[
"Lester",
"Christopher G.",
""
],
[
"Tombs",
"Rupert",
""
]
] | Testing whether data breaks symmetries of interest can be important to many fields. This paper describes a simple way that machine learning algorithms (whose outputs have been appropriately symmetrised) can be used to detect symmetry breaking. The original motivation for the paper was an important question in Particle Physics: "Is parity violated at the LHC in some way that no-one has anticipated?" and so we illustrate the main idea with an example strongly related to that question. However, in order that the key ideas be accessible to readers who are not particle physicists but who are interesting in symmetry breaking, we choose to illustrate the method/approach with a 'toy' example which places a simple discrete source of symmetry breaking (the handedness of human handwriting) within a idealised particle-physics-like context. Readers interested in seeing extensions to continuous symmetries, non-ideal environments or more realistic particle-physics contexts are provided with links to separate papers which delve into such details. |
2211.01302 | Raquel Molina Ms. | R. Molina and E. Oset | The $T_{c\bar{s}}(2900)$ as a threshold effect from the interaction of
the $D^*K^*$, $D^*_s\rho$ channels | 5 pages, 8 figures, 1 table | null | 10.1103/PhysRevD.107.056015 | null | hep-ph hep-lat | http://creativecommons.org/licenses/by/4.0/ | We look at the mass distribution of the $D_s^+ \pi^-$ in the $B^0 \to
\bar{D}^0 D_s^+ \pi^-$ decay, where a peak has been observed in the region of
the $D^*_s \rho$, $D^* K^*$ thresholds. By creating these two channels together
with a $\bar{D}^0$ in $B^0$ decay and letting them interact as coupled
channels, we obtain a structure around their thresholds, short of producing a
bound state, which leads to a peak in the $D_s^+ \pi^-$ mass distribution in
the $B^0 \to \bar{D}^0 D_s^+ \pi^-$ decay. We conclude that the interaction
between the $D^*K^*$ and $D^*_s\rho$ is essential to produce the cusp structure
that we associate to the recently seen $T_{c\bar{s}}(2900)$, and that its
experimental width is mainly due to the decay width of the $\rho$ meson. The
peak obtained together with a smooth background reproduces fairly well the
experimental mass distribution observed in the $B_0 \to \bar{D}^0 D_s^+ \pi^-$
decay.
| [
{
"created": "Wed, 2 Nov 2022 17:22:44 GMT",
"version": "v1"
}
] | 2023-03-29 | [
[
"Molina",
"R.",
""
],
[
"Oset",
"E.",
""
]
] | We look at the mass distribution of the $D_s^+ \pi^-$ in the $B^0 \to \bar{D}^0 D_s^+ \pi^-$ decay, where a peak has been observed in the region of the $D^*_s \rho$, $D^* K^*$ thresholds. By creating these two channels together with a $\bar{D}^0$ in $B^0$ decay and letting them interact as coupled channels, we obtain a structure around their thresholds, short of producing a bound state, which leads to a peak in the $D_s^+ \pi^-$ mass distribution in the $B^0 \to \bar{D}^0 D_s^+ \pi^-$ decay. We conclude that the interaction between the $D^*K^*$ and $D^*_s\rho$ is essential to produce the cusp structure that we associate to the recently seen $T_{c\bar{s}}(2900)$, and that its experimental width is mainly due to the decay width of the $\rho$ meson. The peak obtained together with a smooth background reproduces fairly well the experimental mass distribution observed in the $B_0 \to \bar{D}^0 D_s^+ \pi^-$ decay. |
hep-ph/0309091 | Harmen J. Warringa | Jens O. Andersen, Daniel Boer, Harmen J. Warringa | Thermodynamics of the O(N) Nonlinear Sigma Model in 1+1 Dimensions | 8 pages, revtex, 3 eps figures; reference added, improved figure 1,
minor other changes, conclusions unchanged | Phys.Rev. D69 (2004) 076006 | 10.1103/PhysRevD.69.076006 | null | hep-ph | null | The thermodynamics of the O(N) nonlinear sigma model in 1+1 dimensions is
studied. We calculate the pressure to next-to-leading order in the 1/N
expansion and show that at this order, only the minimum of the effective
potential can be rendered finite by temperature-independent renormalization. To
obtain a finite effective potential away from the minimum requires an arbitrary
choice of prescription, which implies that the temperature dependence is
ambiguous. We show that the problem is linked to thermal infrared renormalons.
| [
{
"created": "Tue, 9 Sep 2003 10:32:23 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Jan 2004 11:02:59 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Andersen",
"Jens O.",
""
],
[
"Boer",
"Daniel",
""
],
[
"Warringa",
"Harmen J.",
""
]
] | The thermodynamics of the O(N) nonlinear sigma model in 1+1 dimensions is studied. We calculate the pressure to next-to-leading order in the 1/N expansion and show that at this order, only the minimum of the effective potential can be rendered finite by temperature-independent renormalization. To obtain a finite effective potential away from the minimum requires an arbitrary choice of prescription, which implies that the temperature dependence is ambiguous. We show that the problem is linked to thermal infrared renormalons. |
1010.2811 | Jay Tasson | Jay D. Tasson | Gravitational physics with antimatter | 5 pages, presented at the International Conference on Exotic Atoms
(EXA 2008) and the 9th International Conference on Low Energy Antiproton
Physics (LEAP 2008), Vienna, Austria, September 2008 | Hyperfine Interact.193:291,2009 | 10.1007/s10751-009-0014-9 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The production of low-energy antimatter provides unique opportunities to
search for new physics in an unexplored regime. Testing gravitational
interactions with antimatter is one such opportunity. Here a scenario based on
Lorentz and CPT violation in the Standard- Model Extension is considered in
which anomalous gravitational effects in antimatter could arise.
| [
{
"created": "Thu, 14 Oct 2010 02:45:17 GMT",
"version": "v1"
}
] | 2010-10-15 | [
[
"Tasson",
"Jay D.",
""
]
] | The production of low-energy antimatter provides unique opportunities to search for new physics in an unexplored regime. Testing gravitational interactions with antimatter is one such opportunity. Here a scenario based on Lorentz and CPT violation in the Standard- Model Extension is considered in which anomalous gravitational effects in antimatter could arise. |
hep-ph/9810238 | Arthur Weldon | H. Arthur Weldon | New Mesons in the Chirally Symmetric Plasma | RevTex, 5 pages. Published in proceedings of RHIC Summer Study '96:
Theory Workshop on Relativistic Heavy Ion Collisions, Ed. D.E. Kahana and Y.
Pang, p. 279 | null | null | null | hep-ph | null | A nonperturbative proof is given that the chirally-invariant quark propagator
contains both particle and hole singularities with different dispersion
relations. Mesons made of a quark and a hole will produce dilepton pairs at
masses characteristic of the plasma and with a distinct energy dependence.
| [
{
"created": "Sat, 3 Oct 1998 19:20:28 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Weldon",
"H. Arthur",
""
]
] | A nonperturbative proof is given that the chirally-invariant quark propagator contains both particle and hole singularities with different dispersion relations. Mesons made of a quark and a hole will produce dilepton pairs at masses characteristic of the plasma and with a distinct energy dependence. |
hep-ph/0201256 | V. J. Kolhinen | K.J. Eskola, H. Honkanen, V.J. Kolhinen and C.A. Salgado | Constraints for nuclear gluon shadowing from DIS data | 11 pages, 3 eps figures | Phys.Lett.B532:222-230,2002 | 10.1016/S0370-2693(02)01592-7 | HIP-2002-03/TH, CERN-TH/2002-007 | hep-ph | null | The $Q^2$ dependence of the ratios of the cross sections of deep inelastic
lepton--nucleus scattering is studied in the framework of leading twist, lowest
order perturbative QCD. The $\log Q^2$ slope of the ratio $F_2^{\rm
Sn}/F_2^{\rm C}$ is computed by using the DGLAP evolution equations, and shown
to be sensitive to the nuclear gluon distribution functions. Four different
parametrizations for the nuclear effects of parton distributions are studied.
We show that the NMC data on the $Q^2$ dependence of $F_2^{\rm Sn}/F_2^{\rm C}$
rule out the case where nuclear shadowing (suppression) of gluons at $x\sim
0.01$ is much larger than the shadowing observed in the ratio $F_2^A/F_2^{\rm
D}$. We also show that the possible nonlinear correction terms due to gluon
fusion in the evolution equations do not change this conclusion. Some
consequences for computation of RHIC multiplicities, which probe the region
$x\gsim0.01$, are also discussed.
| [
{
"created": "Mon, 28 Jan 2002 13:01:18 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Eskola",
"K. J.",
""
],
[
"Honkanen",
"H.",
""
],
[
"Kolhinen",
"V. J.",
""
],
[
"Salgado",
"C. A.",
""
]
] | The $Q^2$ dependence of the ratios of the cross sections of deep inelastic lepton--nucleus scattering is studied in the framework of leading twist, lowest order perturbative QCD. The $\log Q^2$ slope of the ratio $F_2^{\rm Sn}/F_2^{\rm C}$ is computed by using the DGLAP evolution equations, and shown to be sensitive to the nuclear gluon distribution functions. Four different parametrizations for the nuclear effects of parton distributions are studied. We show that the NMC data on the $Q^2$ dependence of $F_2^{\rm Sn}/F_2^{\rm C}$ rule out the case where nuclear shadowing (suppression) of gluons at $x\sim 0.01$ is much larger than the shadowing observed in the ratio $F_2^A/F_2^{\rm D}$. We also show that the possible nonlinear correction terms due to gluon fusion in the evolution equations do not change this conclusion. Some consequences for computation of RHIC multiplicities, which probe the region $x\gsim0.01$, are also discussed. |
1107.0801 | C. Q. Geng | C. Q. Geng and Y. K. Hsiao | Semileptonic $B-\to p\bar{p} \ell-\bar{\nu}_\ell$ decays | 10 pages, 3 figures, published version | Physics Letters B704, 495 (2011) | 10.1016/j.physletb.2011.09.065 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the four-body exclusive semileptonic baryonic $\bar B$ decays of
$B^-\to p\bar p \ell^- \bar\nu_{\ell}$ ($\ell=e,\mu,\tau$) in the standard
model. We find that their decay branching ratios are about $(1.0,
1.0,0.5)\times 10^{-4}$, respectively. In particular, the electron mode is
close to the corresponding CLEO's upper limit of $5.2\times 10^{-3}$, while all
results are about one or two orders of magnitude larger than the previous
estimated values for the inclusive modes of $\bar B\to {\bf B\bar B'}\ell \bar
\nu$. Clearly, both B-factories of Belle and BaBar should be able to observe
these exclusive four-body modes.
| [
{
"created": "Tue, 5 Jul 2011 07:29:11 GMT",
"version": "v1"
},
{
"created": "Thu, 13 Oct 2011 06:50:32 GMT",
"version": "v2"
}
] | 2015-05-28 | [
[
"Geng",
"C. Q.",
""
],
[
"Hsiao",
"Y. K.",
""
]
] | We study the four-body exclusive semileptonic baryonic $\bar B$ decays of $B^-\to p\bar p \ell^- \bar\nu_{\ell}$ ($\ell=e,\mu,\tau$) in the standard model. We find that their decay branching ratios are about $(1.0, 1.0,0.5)\times 10^{-4}$, respectively. In particular, the electron mode is close to the corresponding CLEO's upper limit of $5.2\times 10^{-3}$, while all results are about one or two orders of magnitude larger than the previous estimated values for the inclusive modes of $\bar B\to {\bf B\bar B'}\ell \bar \nu$. Clearly, both B-factories of Belle and BaBar should be able to observe these exclusive four-body modes. |
2403.15110 | Barbara Linek | Barbara Linek, Marta {\L}uszczak, Wolfgang Sch\"afer, Antoni Szczurek | Probing gluon GTMDs of the proton in deep inelastic diffractive dijet
production at HERA | 16 pages, 18 figures, 2 tables | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We calculate several differential distributions for diffractive dijets
production in $e p \to e' {\rm jet \, jet} p$ in the pQCD dipole approach using
off diagonal unintegrated gluon distributions (GTMDs). Different models from
the literature are used. We concentrate on the contribution from exclusive $q
\bar q$ dijets.
Results of our calculations are compared to H1 and ZEUS data, including
specific experimental cuts in our calculations. In general, except of one GTMD,
our results are below the HERA data. The considered mechanism is expected to
gives a sizeable contribution to the ZEUS data, while it is negligible in the
kinematics of the H1 measurement.
This is in contrast to recent results from the literature where the
normalization was adjusted to some selected distributions of H1 collaboration
and no agreement with other observables was checked.
The ZEUS data provide stricter limitations on the GTMDs than the H1 data. We
conclude, based on comparison to different observables, that the calculated
cross sections are only a small fraction of the measured ones which contain
probably also processes with pomeron remnant. Alternatively the experimental
data could be explained by inclusion of $q \bar q g$ component.
We present also azimuthal correlations between the sum and the difference of
dijet transverse momenta. The cuts on transverse momenta of jets generate
corresponding azimuthal correlations which can be misidentified as due to
elliptic gluon distributions.
| [
{
"created": "Fri, 22 Mar 2024 11:05:11 GMT",
"version": "v1"
}
] | 2024-03-25 | [
[
"Linek",
"Barbara",
""
],
[
"Łuszczak",
"Marta",
""
],
[
"Schäfer",
"Wolfgang",
""
],
[
"Szczurek",
"Antoni",
""
]
] | We calculate several differential distributions for diffractive dijets production in $e p \to e' {\rm jet \, jet} p$ in the pQCD dipole approach using off diagonal unintegrated gluon distributions (GTMDs). Different models from the literature are used. We concentrate on the contribution from exclusive $q \bar q$ dijets. Results of our calculations are compared to H1 and ZEUS data, including specific experimental cuts in our calculations. In general, except of one GTMD, our results are below the HERA data. The considered mechanism is expected to gives a sizeable contribution to the ZEUS data, while it is negligible in the kinematics of the H1 measurement. This is in contrast to recent results from the literature where the normalization was adjusted to some selected distributions of H1 collaboration and no agreement with other observables was checked. The ZEUS data provide stricter limitations on the GTMDs than the H1 data. We conclude, based on comparison to different observables, that the calculated cross sections are only a small fraction of the measured ones which contain probably also processes with pomeron remnant. Alternatively the experimental data could be explained by inclusion of $q \bar q g$ component. We present also azimuthal correlations between the sum and the difference of dijet transverse momenta. The cuts on transverse momenta of jets generate corresponding azimuthal correlations which can be misidentified as due to elliptic gluon distributions. |
1806.02791 | Siavash Neshatpour | A. Arbey, T. Hurth, F. Mahmoudi, S. Neshatpour | Hadronic and New Physics Contributions to $b \to s$ Transitions | 20 pages, 7 figures. v2: $F_H(B^+ \to K^+ \mu^+ \mu^-)$ added to the
global fit (with no significant change in the results), references added. v3:
typos corrected | Phys. Rev. D 98, 095027 (2018) | 10.1103/PhysRevD.98.095027 | CERN-TH-2018-134, IPM/P.A-507, MITP/18-046 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Assuming the source of the anomalies observed recently in $b \to s$ data to
be new physics, there is a priori no reason to believe that - in the effective
field theory language - only one type of operator is responsible for the
tensions. We thus perform for the first time a global fit where all the Wilson
coefficients which can effectively receive new physics contributions are
considered, allowing for lepton flavour universality breaking effects as well
as contributions from chirality flipped and scalar and pseudoscalar operators,
and find the SM pull taking into account all effective parameters. As a result
of the full fit to all available $b \to s$ data including all relevant Wilson
coefficients, we obtain a total pull of 4.1$\sigma$ with the SM hypothesis
assuming 10% error for the power corrections. Moreover, we make a statistical
comparison to find whether the most favoured explanation of the anomalies is
new physics or underestimated hadronic effects using the most general
parameterisation which is fully consistent with the analyticity structure of
the amplitudes. This Wilks' test will be a very useful tool to analyse the
forthcoming $B\to K^* \mu^+ \mu^-$ data. Because the significance of the
observed tensions in the angular observables in $B \to K^* \mu^+\mu^-$ is
presently dependent on the theory estimation of the hadronic contributions to
these decays, we briefly discuss the various available approaches for taking
into account the long-distance hadronic effects and examine how the different
estimations of these contributions result in distinct significance of the new
physics interpretation of the observed anomalies.
| [
{
"created": "Thu, 7 Jun 2018 17:08:33 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Jun 2018 15:02:49 GMT",
"version": "v2"
},
{
"created": "Thu, 29 Nov 2018 17:45:37 GMT",
"version": "v3"
}
] | 2018-11-30 | [
[
"Arbey",
"A.",
""
],
[
"Hurth",
"T.",
""
],
[
"Mahmoudi",
"F.",
""
],
[
"Neshatpour",
"S.",
""
]
] | Assuming the source of the anomalies observed recently in $b \to s$ data to be new physics, there is a priori no reason to believe that - in the effective field theory language - only one type of operator is responsible for the tensions. We thus perform for the first time a global fit where all the Wilson coefficients which can effectively receive new physics contributions are considered, allowing for lepton flavour universality breaking effects as well as contributions from chirality flipped and scalar and pseudoscalar operators, and find the SM pull taking into account all effective parameters. As a result of the full fit to all available $b \to s$ data including all relevant Wilson coefficients, we obtain a total pull of 4.1$\sigma$ with the SM hypothesis assuming 10% error for the power corrections. Moreover, we make a statistical comparison to find whether the most favoured explanation of the anomalies is new physics or underestimated hadronic effects using the most general parameterisation which is fully consistent with the analyticity structure of the amplitudes. This Wilks' test will be a very useful tool to analyse the forthcoming $B\to K^* \mu^+ \mu^-$ data. Because the significance of the observed tensions in the angular observables in $B \to K^* \mu^+\mu^-$ is presently dependent on the theory estimation of the hadronic contributions to these decays, we briefly discuss the various available approaches for taking into account the long-distance hadronic effects and examine how the different estimations of these contributions result in distinct significance of the new physics interpretation of the observed anomalies. |
hep-ph/0605244 | Olga Shekhovtsova | G. Pancheri, O. Shekhovtsova, G. Venanzoni | Test of FSR in the process $e^+e^-\to\pi^+\pi^-\gamma$ at DA$\Phi$NE and
extraction of the pion form factor at threshold | 13 pages, 6 figures | Phys.Lett.B642:342-349,2006 | 10.1016/j.physletb.2006.09.053 | null | hep-ph | null | Effects due to non-pointlike behaviour of pions in the process
$e^+e^-\to\pi^+\pi^-\gamma$ can arise for hard photons in the final state. By
means of a Monte Carlo event generator, which also includes the contribution of
the direct decay $\phi\to\pi^+\pi^-\gamma$, we estimate these effects in the
framework of Resonance Perturbation Theory. We consider angular cuts used in
the KLOE analysis of the pion form factor at threshold. A method to reveal the
effects of non-pointlike behaviour of pions in a model-independent way is
proposed.
| [
{
"created": "Tue, 23 May 2006 11:35:29 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Pancheri",
"G.",
""
],
[
"Shekhovtsova",
"O.",
""
],
[
"Venanzoni",
"G.",
""
]
] | Effects due to non-pointlike behaviour of pions in the process $e^+e^-\to\pi^+\pi^-\gamma$ can arise for hard photons in the final state. By means of a Monte Carlo event generator, which also includes the contribution of the direct decay $\phi\to\pi^+\pi^-\gamma$, we estimate these effects in the framework of Resonance Perturbation Theory. We consider angular cuts used in the KLOE analysis of the pion form factor at threshold. A method to reveal the effects of non-pointlike behaviour of pions in a model-independent way is proposed. |
1009.1881 | Sergiy Ivashyn | Henryk Czyz, Sergiy Ivashyn | EKHARA Monte Carlo generator for e+e- to e+e-pi0 and e+e- to e+e- pi+pi-
processes | 32 pages, 4 figures, 1 table | Comput.Phys.Commun.182:1338-1349,2011 | 10.1016/j.cpc.2011.01.029 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present EKHARA Monte Carlo event generator of reactions e+e- to e+e- pi0
and e+e- to e+e- pi+pi-. The newly added channel (e+e- to e+e-pi0) is important
for gamma*gamma* physics and can be used for the pion transition form factor
studies at meson factories.
| [
{
"created": "Thu, 9 Sep 2010 20:24:58 GMT",
"version": "v1"
}
] | 2011-04-05 | [
[
"Czyz",
"Henryk",
""
],
[
"Ivashyn",
"Sergiy",
""
]
] | We present EKHARA Monte Carlo event generator of reactions e+e- to e+e- pi0 and e+e- to e+e- pi+pi-. The newly added channel (e+e- to e+e-pi0) is important for gamma*gamma* physics and can be used for the pion transition form factor studies at meson factories. |
2306.02357 | Wei Kou | Gang Xie, Wei Kou, Qiang Fu, Zhenyu Ye, Xurong Chen | Deeply Virtual Compton Scattering at Future Electron-Ion Colliders | 12 pages, 18 figures, 3 Tables | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | The study of hadronic structure has been carried out for many years.
Generalized parton distribution functions (GPDs) give broad information on the
internal structure of hadrons. Combining GPDs and high-energy scattering
experiments, we expect yielding three-dimensional physical quantities from
experiments. Deeply Virtual Compton Scattering (DVCS) process is a powerful
tool to study GPDs. It is one of the important experiments of Electron Ion
Collider (EIC) and Electron ion collider at China (EicC) in the future. In the
initial stage, the proposed EicC will have $3 \sim 5$ GeV polarized electrons
on $12 \sim 25$ GeV polarized protons, with luminosity up to $1 \sim 2 \times
10^{33}$cm$^{-2}$s$^{-1}$. EIC will be constructed in coming years, which will
cover the variable c.m. energies from 30 to 50 GeV, with the luminosity about
$10^{33} \sim 10^{34}$cm$^{-2}$s$^{-1}$. In this work we present a detailed
simulation of DVCS to study the feasibility of experiments at EicC and EIC.
Referring the method used by HERMES Collaboration, and comparing the model
calculations with pseudo data of asymmetries attributed to the DVCS, we
obtained a model-dependent constraint on the total angular momentum of up and
down quarks in the proton.
| [
{
"created": "Sun, 4 Jun 2023 13:27:49 GMT",
"version": "v1"
}
] | 2023-06-06 | [
[
"Xie",
"Gang",
""
],
[
"Kou",
"Wei",
""
],
[
"Fu",
"Qiang",
""
],
[
"Ye",
"Zhenyu",
""
],
[
"Chen",
"Xurong",
""
]
] | The study of hadronic structure has been carried out for many years. Generalized parton distribution functions (GPDs) give broad information on the internal structure of hadrons. Combining GPDs and high-energy scattering experiments, we expect yielding three-dimensional physical quantities from experiments. Deeply Virtual Compton Scattering (DVCS) process is a powerful tool to study GPDs. It is one of the important experiments of Electron Ion Collider (EIC) and Electron ion collider at China (EicC) in the future. In the initial stage, the proposed EicC will have $3 \sim 5$ GeV polarized electrons on $12 \sim 25$ GeV polarized protons, with luminosity up to $1 \sim 2 \times 10^{33}$cm$^{-2}$s$^{-1}$. EIC will be constructed in coming years, which will cover the variable c.m. energies from 30 to 50 GeV, with the luminosity about $10^{33} \sim 10^{34}$cm$^{-2}$s$^{-1}$. In this work we present a detailed simulation of DVCS to study the feasibility of experiments at EicC and EIC. Referring the method used by HERMES Collaboration, and comparing the model calculations with pseudo data of asymmetries attributed to the DVCS, we obtained a model-dependent constraint on the total angular momentum of up and down quarks in the proton. |
1101.3844 | Qi-Shu Yan | Bob Holdom, Qi-Shu Yan | Searches for the $t^\prime$ of a fourth family | 10 pages, 4 eps figures, 5 Tables, publication version | Phys.Rev.D83:114031,2011 | 10.1103/PhysRevD.83.114031 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the detection of the $t^\prime$ of a fourth family during the early
running of LHC with 7 TeV collision energy and 1 fb$^{-1}$ integrated
luminosity. By use of a neural network we show that it is feasible to search
for the $t'$ even with a mass close to the unitarity upper bound, which is in
the 500 to 600 GeV range. We also present results for the Tevatron with $10
\,\, \textrm{fb}^{-1}$. In both cases the search for a fourth family quark
doublet can be significantly enhanced if one incorporates the contribution that
the $b'$ can make to a $t'$-like signal. Thus the bound on the mass of a
degenerate quark doublet should be stronger than the bounds obtained by
treating $t'$ and $b'$ in isolation.
| [
{
"created": "Thu, 20 Jan 2011 08:57:56 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jun 2011 14:30:02 GMT",
"version": "v2"
}
] | 2011-07-04 | [
[
"Holdom",
"Bob",
""
],
[
"Yan",
"Qi-Shu",
""
]
] | We study the detection of the $t^\prime$ of a fourth family during the early running of LHC with 7 TeV collision energy and 1 fb$^{-1}$ integrated luminosity. By use of a neural network we show that it is feasible to search for the $t'$ even with a mass close to the unitarity upper bound, which is in the 500 to 600 GeV range. We also present results for the Tevatron with $10 \,\, \textrm{fb}^{-1}$. In both cases the search for a fourth family quark doublet can be significantly enhanced if one incorporates the contribution that the $b'$ can make to a $t'$-like signal. Thus the bound on the mass of a degenerate quark doublet should be stronger than the bounds obtained by treating $t'$ and $b'$ in isolation. |
1312.4260 | Zhaoxia Heng | Zhaoxia Heng, Liangliang Shang, Yanming Zhang, Yang Zhang, Jingya Zhu | Pair production of 125 GeV Higgs boson in the SM extension with
color-octet scalars at the LHC | 13 pages, 4 figures | JHEP02(2014)083 | 10.1007/JHEP02(2014)083 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Although the Higgs boson mass and single production rate have been determined
more or less precisely, its other properties may deviate significantly from its
predictions in the standard model (SM) due to the uncertainty of Higgs data. In
this work we study the Higgs pair production at the LHC in the Manohar-Wise
model, which extends the SM by one family of color-octet and isospin-doublet
scalars. We first scanned over the parameter space of the Manohar-Wise model
considering exprimental constraints and performed fits in the model to the
latest Higgs data by using the ATLAS and CMS data separately. Then we
calculated the Higgs pair production rate and investigated the potential of its
discovery at the LHC14. We conclude that: (i) Under current constrains
including Higgs data after Run I of the LHC, the cross section of Higgs pair
production in the Manohar-Wise model can be enhanced up to even $10^3$ times
prediction in the SM. (ii) Moreover, the sizable enhancement comes from the
contributions of the CP-odd color-octet scalar $S^A_I$. For lighter scalar
$S^A_I$ and larger values of $|\lambda_I|$, the cross section of Higgs pair
production can be much larger. (iii) After running again of LHC at 14 TeV, most
of the parameter spaces in the Manohar-Wise model can be test. For an
integrated luminosity of 100 fb$^{-1}$ at the LHC14, when the normalized ratio
$R=10$, the process of Higgs pair production can be detected.
| [
{
"created": "Mon, 16 Dec 2013 08:01:33 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Dec 2013 01:12:21 GMT",
"version": "v2"
},
{
"created": "Mon, 24 Feb 2014 08:25:25 GMT",
"version": "v3"
}
] | 2014-02-25 | [
[
"Heng",
"Zhaoxia",
""
],
[
"Shang",
"Liangliang",
""
],
[
"Zhang",
"Yanming",
""
],
[
"Zhang",
"Yang",
""
],
[
"Zhu",
"Jingya",
""
]
] | Although the Higgs boson mass and single production rate have been determined more or less precisely, its other properties may deviate significantly from its predictions in the standard model (SM) due to the uncertainty of Higgs data. In this work we study the Higgs pair production at the LHC in the Manohar-Wise model, which extends the SM by one family of color-octet and isospin-doublet scalars. We first scanned over the parameter space of the Manohar-Wise model considering exprimental constraints and performed fits in the model to the latest Higgs data by using the ATLAS and CMS data separately. Then we calculated the Higgs pair production rate and investigated the potential of its discovery at the LHC14. We conclude that: (i) Under current constrains including Higgs data after Run I of the LHC, the cross section of Higgs pair production in the Manohar-Wise model can be enhanced up to even $10^3$ times prediction in the SM. (ii) Moreover, the sizable enhancement comes from the contributions of the CP-odd color-octet scalar $S^A_I$. For lighter scalar $S^A_I$ and larger values of $|\lambda_I|$, the cross section of Higgs pair production can be much larger. (iii) After running again of LHC at 14 TeV, most of the parameter spaces in the Manohar-Wise model can be test. For an integrated luminosity of 100 fb$^{-1}$ at the LHC14, when the normalized ratio $R=10$, the process of Higgs pair production can be detected. |
2202.07197 | Zhen-Yan Lu | Zhen-Yan Lu, Jian-Feng Xu, Xin-Jian Wen, Guang-Xiong Peng, Marco
Ruggieri | Landau quantization and spin polarization of cold magnetized quark
matter | 10 pages, 7 figures; Manuscript has been accepted for publication as
a Regular Article in Chinese Physics C | Chin.Phys.C 46 (2022) 6, 064104 | 10.1088/1674-1137/ac5513 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by-sa/4.0/ | The magnetic field and density behaviors of various thermodynamic quantities
of strange quark matter under compact star conditions are investigated in the
framework of the thermodynamically self-consistent quasiparticle model. For
individual species, a larger number density $n_i$ leads to a larger magnetic
field strength threshold that align all particles parallel or antiparallel to
the magnetic field. Accordingly, in contrast to the finite baryon density
effect which reduces the spin polarization of magnetized strange quark matter,
the magnetic field effect leads to an enhancement of it. We also compute the
sound velocity as a function of the baryon density and find the sound velocity
shows an obvious oscillation with increasing density. Except for the
oscillation, similar to the zero-magnetic field case that the sound velocity
grows with increasing density and approaches the conformal limit $V_s^2=1/3$ at
high densities from below.
| [
{
"created": "Tue, 15 Feb 2022 05:11:05 GMT",
"version": "v1"
}
] | 2022-03-15 | [
[
"Lu",
"Zhen-Yan",
""
],
[
"Xu",
"Jian-Feng",
""
],
[
"Wen",
"Xin-Jian",
""
],
[
"Peng",
"Guang-Xiong",
""
],
[
"Ruggieri",
"Marco",
""
]
] | The magnetic field and density behaviors of various thermodynamic quantities of strange quark matter under compact star conditions are investigated in the framework of the thermodynamically self-consistent quasiparticle model. For individual species, a larger number density $n_i$ leads to a larger magnetic field strength threshold that align all particles parallel or antiparallel to the magnetic field. Accordingly, in contrast to the finite baryon density effect which reduces the spin polarization of magnetized strange quark matter, the magnetic field effect leads to an enhancement of it. We also compute the sound velocity as a function of the baryon density and find the sound velocity shows an obvious oscillation with increasing density. Except for the oscillation, similar to the zero-magnetic field case that the sound velocity grows with increasing density and approaches the conformal limit $V_s^2=1/3$ at high densities from below. |
hep-ph/0603125 | Houri Ziaeepour | Houri Ziaeepour | Condensation of a Classical Scalar Field After Inflation and Dark Energy | 19 pages, no figures,v2: a reference is added,v3: text improved | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In cosmological context, classical scalar fields are important ingredients
for inflation models, many candidate models of dark energy, symmetry breaking
and phase transition epochs, and their consequences such as baryo and
lepto-genesis. We investigate the formation of these fields by studying the
production of a light quantum scalar field during the decay of a heavy
particle. For simplicity it is assumed to be a scalar too. We discuss the
effects of the decay mode, the thermodynamical state of the decaying field,
boundary conditions, and related physical parameters on the production and
evolution of a condensate. For a simplified version of this model we calculate
the asymptotic behaviour of the condensate and conditions for its contribution
to the dark energy with an equation of state close to a cosmological constant.
We also discus the role of the back-reaction from interactions with other
fields and expansion of the Universe on the evolution of the condensate.
| [
{
"created": "Thu, 16 Mar 2006 15:51:18 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Apr 2006 09:46:36 GMT",
"version": "v2"
},
{
"created": "Sun, 1 Feb 2009 20:21:15 GMT",
"version": "v3"
},
{
"created": "Mon, 21 Sep 2009 12:55:00 GMT",
"version": "v4"
}
] | 2009-09-21 | [
[
"Ziaeepour",
"Houri",
""
]
] | In cosmological context, classical scalar fields are important ingredients for inflation models, many candidate models of dark energy, symmetry breaking and phase transition epochs, and their consequences such as baryo and lepto-genesis. We investigate the formation of these fields by studying the production of a light quantum scalar field during the decay of a heavy particle. For simplicity it is assumed to be a scalar too. We discuss the effects of the decay mode, the thermodynamical state of the decaying field, boundary conditions, and related physical parameters on the production and evolution of a condensate. For a simplified version of this model we calculate the asymptotic behaviour of the condensate and conditions for its contribution to the dark energy with an equation of state close to a cosmological constant. We also discus the role of the back-reaction from interactions with other fields and expansion of the Universe on the evolution of the condensate. |
2303.00781 | Benjamin Lehmann | Wolfgang Altmannshofer, Stefania Gori, Benjamin V. Lehmann and
Jianhong Zuo | UV physics from IR features: new prospects from top flavor violation | 16 pages, 6 figures. Matched published version | Phys. Rev. D 107, 095025 (2023) | 10.1103/PhysRevD.107.095025 | MIT-CTP/5534 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | New physics in the rare top decays $t \to q \ell^+\ell^-$ is currently very
weakly constrained. We show that in a large class of Standard Model extensions,
existing experimental constraints on new physics in flavor-conserving processes
imply strong indirect bounds on new physics contributions to flavor-violating
processes of the form $t \to q \ell^+\ell^-$. These indirect bounds arise from
basic principles of quantum field theory together with a few generic conditions
on the UV structure of the theory, and are roughly an order of magnitude
stronger than the present experimental bounds on the same processes. These
constraints provide a theoretically motivated target for experimental searches
for $t \to q \ell^+\ell^-$: violation of these bounds would exclude a large
class of new physics models, and would provide nontrivial insight into the UV
behavior of the new physics.
| [
{
"created": "Wed, 1 Mar 2023 19:08:46 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Jul 2023 01:46:11 GMT",
"version": "v2"
}
] | 2023-07-17 | [
[
"Altmannshofer",
"Wolfgang",
""
],
[
"Gori",
"Stefania",
""
],
[
"Lehmann",
"Benjamin V.",
""
],
[
"Zuo",
"Jianhong",
""
]
] | New physics in the rare top decays $t \to q \ell^+\ell^-$ is currently very weakly constrained. We show that in a large class of Standard Model extensions, existing experimental constraints on new physics in flavor-conserving processes imply strong indirect bounds on new physics contributions to flavor-violating processes of the form $t \to q \ell^+\ell^-$. These indirect bounds arise from basic principles of quantum field theory together with a few generic conditions on the UV structure of the theory, and are roughly an order of magnitude stronger than the present experimental bounds on the same processes. These constraints provide a theoretically motivated target for experimental searches for $t \to q \ell^+\ell^-$: violation of these bounds would exclude a large class of new physics models, and would provide nontrivial insight into the UV behavior of the new physics. |
1509.00465 | Dmitri Kharzeev | Dmitri E. Kharzeev | Color confinement from fluctuating topology | 14 pages, 3 figures; contribution to the Gribov-85 Memorial volume | null | null | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | QCD possesses a compact gauge group, and this implies a non-trivial
topological structure of the vacuum. In this contribution to the Gribov-85
Memorial volume, we first discuss the origin of Gribov copies and their
interpretation in terms of fluctuating topology in the QCD vacuum. We then
describe the recent work with E. Levin that links the confinement of gluons and
color screening to the fluctuating topology, and discuss implications for spin
physics, high energy scattering, and the physics of quark-gluon plasma.
| [
{
"created": "Tue, 1 Sep 2015 19:58:55 GMT",
"version": "v1"
}
] | 2015-09-02 | [
[
"Kharzeev",
"Dmitri E.",
""
]
] | QCD possesses a compact gauge group, and this implies a non-trivial topological structure of the vacuum. In this contribution to the Gribov-85 Memorial volume, we first discuss the origin of Gribov copies and their interpretation in terms of fluctuating topology in the QCD vacuum. We then describe the recent work with E. Levin that links the confinement of gluons and color screening to the fluctuating topology, and discuss implications for spin physics, high energy scattering, and the physics of quark-gluon plasma. |
1308.1635 | Marco Guzzi | Marco Guzzi, Katerina Lipka and Sven-Olaf Moch | Top-quark production at the LHC: differential cross section and
phenomenological applications | 5 pages, 2 Figures, conference proceeding, DIS2013: XXI International
Workshop on Deep-Inelastic Scattering and Related Subjects 22-26 April 2013,
Marseilles, France | null | null | DESY 13-141 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss top-quark pair production at hadron colliders and review available
calculations of differential top-pair production cross section in perturbative
QCD at approximate next-to-next-to-leading order (NNLO) within the threshold
resummation formalism. These calculations are implemented into an open source
program under development. We present phenomenological studies at the LHC that
include transverse momentum and rapidity distribution of the top quarks at a
center-of-mass energy of 7 TeV. Preliminary results obtained with this program
are in very good agreement with the recent LHC measurements.
| [
{
"created": "Wed, 7 Aug 2013 17:07:06 GMT",
"version": "v1"
}
] | 2013-08-08 | [
[
"Guzzi",
"Marco",
""
],
[
"Lipka",
"Katerina",
""
],
[
"Moch",
"Sven-Olaf",
""
]
] | We discuss top-quark pair production at hadron colliders and review available calculations of differential top-pair production cross section in perturbative QCD at approximate next-to-next-to-leading order (NNLO) within the threshold resummation formalism. These calculations are implemented into an open source program under development. We present phenomenological studies at the LHC that include transverse momentum and rapidity distribution of the top quarks at a center-of-mass energy of 7 TeV. Preliminary results obtained with this program are in very good agreement with the recent LHC measurements. |
hep-ph/9705460 | Georges Grunberg | G. Grunberg | 1/Q^2 terms and Landau singularity | 6 pages, latex, no figures; talk presented at the Moriond Conference
``QCD and High Energy Hadronic Interactions'', Les Arcs, France, March 22-29,
1997 | null | null | CPTh/PC 510.0597 | hep-ph | null | Standard power-behaved contributions in QCD arising from non-perturbative
effects at low scale can be described, as shown by Dokshitzer, Marchesini and
Webber, with the notion of an infrared regular effective coupling. In their
approach, a non-perturbative contribution to the coupling, essentially
restricted to low scales, parametrizes the non-perturbative power corrections.
I argue that their framework naturally allows for another type of power
contributions, arising from short distances (hence unrelated to renormalons and
the operator product expansion) which appear in the process of removing the
Landau singularity present in perturbation theory. A natural definition of an
infrared finite perturbative coupling is suggested within the dispersive
method. Implications for the tau hadronic width, where $O(1/Q^2)$ contributions
can be generated, are pointed out.
| [
{
"created": "Thu, 29 May 1997 15:05:06 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Grunberg",
"G.",
""
]
] | Standard power-behaved contributions in QCD arising from non-perturbative effects at low scale can be described, as shown by Dokshitzer, Marchesini and Webber, with the notion of an infrared regular effective coupling. In their approach, a non-perturbative contribution to the coupling, essentially restricted to low scales, parametrizes the non-perturbative power corrections. I argue that their framework naturally allows for another type of power contributions, arising from short distances (hence unrelated to renormalons and the operator product expansion) which appear in the process of removing the Landau singularity present in perturbation theory. A natural definition of an infrared finite perturbative coupling is suggested within the dispersive method. Implications for the tau hadronic width, where $O(1/Q^2)$ contributions can be generated, are pointed out. |
hep-ph/0009323 | Johannes Bluemlein | Johannes Bl\"umlein | Precision of electro--weak couplings of scalar leptoquarks at TESLA | 4 pages LATEX, 2 Refs. added | null | null | LC-TH-2000-50 | hep-ph | null | We investigate the potential to measure the electro-weak couplings of scalar
leptoquarks $\Phi_s$ at TESLA for energies in the range of $\sqrt{s} \simeq 1
\TeV$ using the pair production process $e^+e^- \to \Phi_s \bar{\Phi}_s$.
| [
{
"created": "Thu, 28 Sep 2000 13:06:55 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Nov 2000 15:17:03 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Blümlein",
"Johannes",
""
]
] | We investigate the potential to measure the electro-weak couplings of scalar leptoquarks $\Phi_s$ at TESLA for energies in the range of $\sqrt{s} \simeq 1 \TeV$ using the pair production process $e^+e^- \to \Phi_s \bar{\Phi}_s$. |
1008.1313 | Shunzo Kumano | M. Hirai, S. Kumano, K. Saito, T. Watanabe | Clustering aspects in nuclear structure functions | 11 pages, LaTeX, 10 eps files, Physical Review C in press | Phys.Rev.C83:035202,2011 | 10.1103/PhysRevC.83.035202 | KEK-TH-1363 | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | For understanding an anomalous nuclear effect experimentally observed for the
beryllium-9 nucleus at the Thomas Jefferson National Accelerator Facility
(JLab), clustering aspects are studied in structure functions of deep inelastic
lepton-nucleus scattering by using momentum distributions calculated in
antisymmetrized (or fermionic) molecular dynamics (AMD) and also in a simple
shell model for comparison. According to the AMD, the Be-9 nucleus consists of
two alpha-like clusters with a surrounding neutron. The clustering produces
high-momentum components in nuclear wave functions, which affects nuclear
modifications of the structure functions. We investigated whether clustering
features could appear in the structure function F_2 of Be-9 along with studies
for other light nuclei. We found that nuclear modifications of F_2 are similar
in both AMD and shell models within our simple convolution description although
there are slight differences in Be-9. It indicates that the anomalous Be-9
result should be explained by a different mechanism from the nuclear binding
and Fermi motion. If nuclear-modification slopes d(F_2^A/F_2^D)/dx are shown by
the maximum local densities, the Be-9 anomaly can be explained by the AMD
picture, namely by the clustering structure, whereas it certainly cannot be
described in the simple shell model. This fact suggests that the large nuclear
modification in Be-9 should be explained by large densities in the clusters.
For example, internal nucleon structure could be modified in the high-density
clusters. The clustering aspect of nuclear structure functions is an unexplored
topic which is interesting for future investigations.
| [
{
"created": "Sat, 7 Aug 2010 08:20:50 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Feb 2011 06:14:37 GMT",
"version": "v2"
}
] | 2011-03-23 | [
[
"Hirai",
"M.",
""
],
[
"Kumano",
"S.",
""
],
[
"Saito",
"K.",
""
],
[
"Watanabe",
"T.",
""
]
] | For understanding an anomalous nuclear effect experimentally observed for the beryllium-9 nucleus at the Thomas Jefferson National Accelerator Facility (JLab), clustering aspects are studied in structure functions of deep inelastic lepton-nucleus scattering by using momentum distributions calculated in antisymmetrized (or fermionic) molecular dynamics (AMD) and also in a simple shell model for comparison. According to the AMD, the Be-9 nucleus consists of two alpha-like clusters with a surrounding neutron. The clustering produces high-momentum components in nuclear wave functions, which affects nuclear modifications of the structure functions. We investigated whether clustering features could appear in the structure function F_2 of Be-9 along with studies for other light nuclei. We found that nuclear modifications of F_2 are similar in both AMD and shell models within our simple convolution description although there are slight differences in Be-9. It indicates that the anomalous Be-9 result should be explained by a different mechanism from the nuclear binding and Fermi motion. If nuclear-modification slopes d(F_2^A/F_2^D)/dx are shown by the maximum local densities, the Be-9 anomaly can be explained by the AMD picture, namely by the clustering structure, whereas it certainly cannot be described in the simple shell model. This fact suggests that the large nuclear modification in Be-9 should be explained by large densities in the clusters. For example, internal nucleon structure could be modified in the high-density clusters. The clustering aspect of nuclear structure functions is an unexplored topic which is interesting for future investigations. |
0809.1093 | Iain W. Stewart | Claudio Marcantonini, Iain W. Stewart | Reparameterization Invariant Collinear Operators | 45 pages, Journal Version, Ref. added | Phys.Rev.D79:065028,2009 | 10.1103/PhysRevD.79.065028 | MIT CTP-3609 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In constructing collinear operators, which describe the production of
energetic jets or energetic hadrons, important constraints are provided by
reparameterization invariance (RPI). RPI encodes Lorentz invariance in a power
expansion about a collinear direction, and connects the Wilson coefficients of
operators at different orders in this expansion to all orders in alphas. We
construct reparameterization invariant collinear objects. The expansion of
operators built from these objects provides an efficient way of deriving RPI
relations and finding a minimal basis of operators, particularly when one has
an observable with multiple collinear directions and/or soft particles.
Complete basis of operators are constructed for pure glue currents at twist-4,
and for operators involving multiple collinear directions, including those
appearing in e+e- -> 3 jets, and for pp-> 2 jets initiated via gluon-fusion.
| [
{
"created": "Mon, 8 Sep 2008 19:54:22 GMT",
"version": "v1"
},
{
"created": "Sun, 25 Jan 2009 05:32:12 GMT",
"version": "v2"
}
] | 2009-11-06 | [
[
"Marcantonini",
"Claudio",
""
],
[
"Stewart",
"Iain W.",
""
]
] | In constructing collinear operators, which describe the production of energetic jets or energetic hadrons, important constraints are provided by reparameterization invariance (RPI). RPI encodes Lorentz invariance in a power expansion about a collinear direction, and connects the Wilson coefficients of operators at different orders in this expansion to all orders in alphas. We construct reparameterization invariant collinear objects. The expansion of operators built from these objects provides an efficient way of deriving RPI relations and finding a minimal basis of operators, particularly when one has an observable with multiple collinear directions and/or soft particles. Complete basis of operators are constructed for pure glue currents at twist-4, and for operators involving multiple collinear directions, including those appearing in e+e- -> 3 jets, and for pp-> 2 jets initiated via gluon-fusion. |
2110.02183 | Emanuele Re | Emanuele Re | Recent progress on high order calculations and matching to parton
showers | 8 pages, 2 figures. Submitted to the proceedings of the 9th annual
Large Hadron Collider Physics conference, LHCP2021, 7-12 June, 2021 | null | null | LAPTH-Conf-029/21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I give an overview of the recent progress on the matching of fixed-order
calculations and parton showers. The focus is on the matching with NNLO QCD
corrections as well as with NLO EW ones.
| [
{
"created": "Tue, 5 Oct 2021 17:23:09 GMT",
"version": "v1"
}
] | 2021-10-06 | [
[
"Re",
"Emanuele",
""
]
] | I give an overview of the recent progress on the matching of fixed-order calculations and parton showers. The focus is on the matching with NNLO QCD corrections as well as with NLO EW ones. |
hep-ph/0411082 | Vladimir Galkin | D. Ebert, R.N. Faustov, V.O. Galkin, A.P. Martynenko | Masses and weak decay rates of doubly heavy baryons | Talk given at 13th International Seminar Quarks-2004, Pushkinskie
Gory, Russia, 24-30 May 2004, 10 pages | null | null | null | hep-ph | null | Mass spectra and semileptonic decay rates of doubly heavy baryons are studied
in the framework of the relativistic quark model in the quark-diquark
approximation.
| [
{
"created": "Fri, 5 Nov 2004 09:50:56 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Ebert",
"D.",
""
],
[
"Faustov",
"R. N.",
""
],
[
"Galkin",
"V. O.",
""
],
[
"Martynenko",
"A. P.",
""
]
] | Mass spectra and semileptonic decay rates of doubly heavy baryons are studied in the framework of the relativistic quark model in the quark-diquark approximation. |
1606.06678 | Alexandre Kisselev | A.V. Kisselev | Approximate formula for total cross section for moderately small eikonal
function | 29 pages, 5 figures. Title is slightly corrected. Section 3 is
rewritten. Two new sections are added. Appendix B is removed, three new
appendices are added | null | null | null | hep-ph math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The eikonal approximation for the total cross section for the scattering of
two unpolarized particles is studied. The approximate formula in the case when
the eikonal function chi(b) is moderately small, |chi(b)| < 0.1, is derived. It
is shown that the total cross section is given by the series of multiple
improper integrals of the Born amplitude A_B. Its advantage compared to
standard eikonal formulas is that the integrals contain no rapidly oscillating
Bessel functions. Two theorems which allow one to relate large-b behavior of
chi(b) with analytical properties of the Born amplitude are proved. Several
examples of these theorems are given. To check the efficiency of the main
formula, it is applied for numerical calculations of the total cross section
for a number of particular expressions of A_B. Only those Born amplitudes are
chosen which result in moderately small eikonal functions and lead to the
correct asymptotics of chi(b). The numerical calculations show that our formula
approximates the total cross section with the relative error of O(10^(-5)),
provided that the first three non-zero terms in it are taken into account.
| [
{
"created": "Sun, 19 Jun 2016 14:06:26 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Jul 2016 08:34:39 GMT",
"version": "v2"
},
{
"created": "Thu, 6 Jun 2019 13:10:06 GMT",
"version": "v3"
}
] | 2019-06-07 | [
[
"Kisselev",
"A. V.",
""
]
] | The eikonal approximation for the total cross section for the scattering of two unpolarized particles is studied. The approximate formula in the case when the eikonal function chi(b) is moderately small, |chi(b)| < 0.1, is derived. It is shown that the total cross section is given by the series of multiple improper integrals of the Born amplitude A_B. Its advantage compared to standard eikonal formulas is that the integrals contain no rapidly oscillating Bessel functions. Two theorems which allow one to relate large-b behavior of chi(b) with analytical properties of the Born amplitude are proved. Several examples of these theorems are given. To check the efficiency of the main formula, it is applied for numerical calculations of the total cross section for a number of particular expressions of A_B. Only those Born amplitudes are chosen which result in moderately small eikonal functions and lead to the correct asymptotics of chi(b). The numerical calculations show that our formula approximates the total cross section with the relative error of O(10^(-5)), provided that the first three non-zero terms in it are taken into account. |
1708.00797 | Wouter Dekens | W. Dekens | $\epsilon'$ from right-handed currents | Added references | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent lattice determinations of direct CP violation in kaon decays,
parametrized by $\epsilon'$, suggest a discrepancy of several sigma between
experiment and the standard model. Assuming that this situation is due to new
physics, we investigate a solution in terms of right-handed charged currents.
Chiral perturbation theory, in combination with lattice QCD results, allows one
to accurately determine the effect of right-handed interactions on $\epsilon'$.
In addition, similar techniques provide a direct link between the right-handed
contributions to $\epsilon'$ and hadronic electric dipole moments. We
demonstrate that the $\epsilon'$ discrepancy can be resolved with right-handed
charged currents, and that this scenario can be falsified by next-generation
hadronic electric dipole moment experiments.
| [
{
"created": "Wed, 2 Aug 2017 15:37:56 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Oct 2017 15:29:06 GMT",
"version": "v2"
}
] | 2017-10-05 | [
[
"Dekens",
"W.",
""
]
] | Recent lattice determinations of direct CP violation in kaon decays, parametrized by $\epsilon'$, suggest a discrepancy of several sigma between experiment and the standard model. Assuming that this situation is due to new physics, we investigate a solution in terms of right-handed charged currents. Chiral perturbation theory, in combination with lattice QCD results, allows one to accurately determine the effect of right-handed interactions on $\epsilon'$. In addition, similar techniques provide a direct link between the right-handed contributions to $\epsilon'$ and hadronic electric dipole moments. We demonstrate that the $\epsilon'$ discrepancy can be resolved with right-handed charged currents, and that this scenario can be falsified by next-generation hadronic electric dipole moment experiments. |
1009.5171 | Mitsuo J. Hayashi | Yuta Koshimizu, Toyokazu Fukuoka, Kenji Takagi, Hikoya Kasari and
Mitsuo J. Hayashi | Dilatonic Inflation, Gravitino and Reheating in Modified Modular
invariant Supergravity | 12 pages, 4 figures, 2 tables | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new modified string-inspired modular invariant supergravity model is
proposed and is applied to realize the slow roll inflation in Einstein frame,
so that the model explains WMAP observations very well. Gravitino mass and
their production rate from scalar fields are estimated at certain values of
parameters in the model. Seven cases of parameter choices are discussed here,
among which some examples show the possibility of observation of gauginos by
LHC experiments, which will give some hints of identity of dark matters. The
reheating temperature, which is estimated by the stability condition of
Boltzmann equation by using the decay rates of the dilaton $S$ into gauginos,
is lower than the mass of gravitino. Therefore no thermal reproduction of
gravitinos happens. The ratio between the scalar and tensor power spectrum is
predicted to be almost the same for the seven cases under study, and its value
$r \sim 6.8 \times 10^{-2}$ seems in the range possibly observed by the Planck
satellite soon. The plausible supergravity model of inflation, which will be
described here, will open the hope to construct a realistic theory of particles
and cosmology in this framework, including yet undetected objects.
| [
{
"created": "Mon, 27 Sep 2010 07:14:13 GMT",
"version": "v1"
},
{
"created": "Mon, 4 Oct 2010 06:22:47 GMT",
"version": "v2"
},
{
"created": "Mon, 22 Nov 2010 07:30:13 GMT",
"version": "v3"
}
] | 2010-11-23 | [
[
"Koshimizu",
"Yuta",
""
],
[
"Fukuoka",
"Toyokazu",
""
],
[
"Takagi",
"Kenji",
""
],
[
"Kasari",
"Hikoya",
""
],
[
"Hayashi",
"Mitsuo J.",
""
]
] | A new modified string-inspired modular invariant supergravity model is proposed and is applied to realize the slow roll inflation in Einstein frame, so that the model explains WMAP observations very well. Gravitino mass and their production rate from scalar fields are estimated at certain values of parameters in the model. Seven cases of parameter choices are discussed here, among which some examples show the possibility of observation of gauginos by LHC experiments, which will give some hints of identity of dark matters. The reheating temperature, which is estimated by the stability condition of Boltzmann equation by using the decay rates of the dilaton $S$ into gauginos, is lower than the mass of gravitino. Therefore no thermal reproduction of gravitinos happens. The ratio between the scalar and tensor power spectrum is predicted to be almost the same for the seven cases under study, and its value $r \sim 6.8 \times 10^{-2}$ seems in the range possibly observed by the Planck satellite soon. The plausible supergravity model of inflation, which will be described here, will open the hope to construct a realistic theory of particles and cosmology in this framework, including yet undetected objects. |
hep-ph/0307235 | Soon-Tae Hong | Soon-Tae Hong | Proton strange form factors and SAMPLE experiments | 3 pages | Nucl.Phys. A721 (2003) 421c-424c | 10.1016/S0375-9474(03)01087-X | null | hep-ph | null | We study the chiral models such as the Skyrmion and chiral bag to investigate
the baryon strange form factors associated with the SAMPLE experiments.
| [
{
"created": "Fri, 18 Jul 2003 11:42:32 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Hong",
"Soon-Tae",
""
]
] | We study the chiral models such as the Skyrmion and chiral bag to investigate the baryon strange form factors associated with the SAMPLE experiments. |
hep-ph/9203207 | null | Peter Haagensen and Jose I. Latorre | Differential Renormalization of Massive Quantum Field Theories | 8 pages(LaTex, no figures) | Phys.Lett. B283 (1992) 293-297 | 10.1016/0370-2693(92)90022-V | null | hep-ph | null | We extend the method of differential renormalization to massive quantum field
theories treating in particular $\ph4$-theory and QED. As in the massless case,
the method proves to be simple and powerful, and we are able to find, in
particular, compact explicit coordinate space expressions for the finite parts
of two notably complicated diagrams, namely, the 2-loop 2-point function in
$\ph4$ and the 1-loop vertex in QED.
| [
{
"created": "Tue, 10 Mar 1992 15:09:19 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Haagensen",
"Peter",
""
],
[
"Latorre",
"Jose I.",
""
]
] | We extend the method of differential renormalization to massive quantum field theories treating in particular $\ph4$-theory and QED. As in the massless case, the method proves to be simple and powerful, and we are able to find, in particular, compact explicit coordinate space expressions for the finite parts of two notably complicated diagrams, namely, the 2-loop 2-point function in $\ph4$ and the 1-loop vertex in QED. |
hep-ph/0511017 | Peter Schweitzer | M.Anselmino, M.Boglione, J.C.Collins, U.D'Alesio, A.V.Efremov,
K.Goeke, A.Kotzinian, S.Menzel, A.Metz, F.Murgia, A.Prokudin, P.Schweitzer,
W.Vogelsang, F.Yuan | Comparing extractions of Sivers functions | Contribution to the proceedings of "The International Workshop on
Transverse Polarisation Phenomena in Hard Processes" (Transversity 2005),
Villa Olmo (Como), 7-10th. September 2005 | null | 10.1142/9789812773272_0028 | BNL-NT-05/42, RBRC-572, RUB-TPII-14-05 | hep-ph | null | A comparison is given of the various recently published extractions of the
Sivers functions from the HERMES and COMPASS data on single-transverse spin
asymmetries in semi-inclusive deeply inelastic scattering.
| [
{
"created": "Wed, 2 Nov 2005 12:27:16 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Anselmino",
"M.",
""
],
[
"Boglione",
"M.",
""
],
[
"Collins",
"J. C.",
""
],
[
"D'Alesio",
"U.",
""
],
[
"Efremov",
"A. V.",
""
],
[
"Goeke",
"K.",
""
],
[
"Kotzinian",
"A.",
""
],
[
"Menzel",
"S.",
""
],
[
"Metz",
"A.",
""
],
[
"Murgia",
"F.",
""
],
[
"Prokudin",
"A.",
""
],
[
"Schweitzer",
"P.",
""
],
[
"Vogelsang",
"W.",
""
],
[
"Yuan",
"F.",
""
]
] | A comparison is given of the various recently published extractions of the Sivers functions from the HERMES and COMPASS data on single-transverse spin asymmetries in semi-inclusive deeply inelastic scattering. |
2305.10753 | Takuma Nishibuchi | Takuma Nishibuchi, Tetsuo Hyodo | Analysis of $\Xi(1620)$ resonance and $\bar{K}\Lambda$ scattering length
with chiral unitary approach | 12 pages, 11 figures | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the $\Xi(1620)$ resonance near the $\bar{K}\Lambda$ threshold in the
light of the recent experimental constraints. The Belle collaboration have
found a resonance peak of $\Xi(1620)$ slightly below the $\bar{K}^{0}\Lambda$
threshold in the $\pi^{+}\Xi^{-}$ invariant mass spectrum, and the ALICE
collaboration have determined the $K^{-}\Lambda$ scattering length from the
measurement of the momentum correlation functions in the heavy ion collisions.
Using the effective range expansion, we classify the nature of the pole of the
near-threshold eigenstate in terms of the scattering length, in the presence of
the decay channel. It is shown that the quasibound state below the threshold
can be described by only the scattering length, while the description of the
resonance above the threshold requires the contribution from the effective
range. Based on the chiral unitary approach, we construct a theoretical model
which generates the pole of $\Xi(1620)$ below the $\bar{K}\Lambda$ threshold
with relatively narrow width, as reported by the Belle collaboration. It is
quantitatively demonstrated that the spectrum of the $\Xi(1620)$ quasibound
state is distorted by the effect of the nearby $\bar{K}\Lambda$ threshold. We
then construct another model which reproduces the $K^{-}\Lambda$ scattering
length by the ALICE collaboration. In this case, the eigenstate pole does not
appear in the physically relevant Riemann sheets, and the spectrum shows a cusp
structure at the $\bar{K}\Lambda$ threshold. We finally examine the
compatibility of the value of the $\bar{K}\Lambda$ scattering length and the
subthreshold pole of $\Xi(1620)$ including the experimental uncertainties.
| [
{
"created": "Thu, 18 May 2023 06:53:16 GMT",
"version": "v1"
}
] | 2023-05-19 | [
[
"Nishibuchi",
"Takuma",
""
],
[
"Hyodo",
"Tetsuo",
""
]
] | We study the $\Xi(1620)$ resonance near the $\bar{K}\Lambda$ threshold in the light of the recent experimental constraints. The Belle collaboration have found a resonance peak of $\Xi(1620)$ slightly below the $\bar{K}^{0}\Lambda$ threshold in the $\pi^{+}\Xi^{-}$ invariant mass spectrum, and the ALICE collaboration have determined the $K^{-}\Lambda$ scattering length from the measurement of the momentum correlation functions in the heavy ion collisions. Using the effective range expansion, we classify the nature of the pole of the near-threshold eigenstate in terms of the scattering length, in the presence of the decay channel. It is shown that the quasibound state below the threshold can be described by only the scattering length, while the description of the resonance above the threshold requires the contribution from the effective range. Based on the chiral unitary approach, we construct a theoretical model which generates the pole of $\Xi(1620)$ below the $\bar{K}\Lambda$ threshold with relatively narrow width, as reported by the Belle collaboration. It is quantitatively demonstrated that the spectrum of the $\Xi(1620)$ quasibound state is distorted by the effect of the nearby $\bar{K}\Lambda$ threshold. We then construct another model which reproduces the $K^{-}\Lambda$ scattering length by the ALICE collaboration. In this case, the eigenstate pole does not appear in the physically relevant Riemann sheets, and the spectrum shows a cusp structure at the $\bar{K}\Lambda$ threshold. We finally examine the compatibility of the value of the $\bar{K}\Lambda$ scattering length and the subthreshold pole of $\Xi(1620)$ including the experimental uncertainties. |
1710.03933 | Tianhong Wang | Si-Chen Li, Tianhong Wang, Yue Jiang, Xiao-Ze Tan, Qiang Li, Guo-Li
Wang, Chao-Hsi Chang | Strong decays of $D_J(3000)$ and $D_{sJ}(3040)$ | 22 pages, 2 figures | Phys. Rev. D 97, 054002 (2018) | 10.1103/PhysRevD.97.054002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we systematically calculate two-body strong decays of newly
observed $D_J(3000)$ and $D_{sJ}(3040)$ with 2P$(1^+)$ and 2P$(1^{+\prime})$
assignments in an instantaneous approximation of the Bethe-Salpeter equation
method. Our results show that both resonances can be explained as the
2P$(1^{+'})$ with broad width via $^3P_1$ and $^1P_1$ mixing in $D$ and $D_s$
families. For $D_J(3000)$, the total width is 229.6 MeV in our calculation,
close to the upper limit of experimental data, and the dominant decay channels
are $D_2^*\pi$, $D^*\pi$, and $D^*(2600)\pi$. For $D_{sJ}(3040)$, the total
width is 157.4 MeV in our calculation, close to the lower limit of experimental
data, and the dominant channels are $D^*K$ and $D^*K^*$. These results are
consistent with observed channels in experiments. Given the very little
information that has been obtained from experiments and the large error bars of
the total decay widths, we recommend the detection of dominant channels in our
calculation.
| [
{
"created": "Wed, 11 Oct 2017 07:01:50 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Mar 2018 14:17:57 GMT",
"version": "v2"
}
] | 2018-03-14 | [
[
"Li",
"Si-Chen",
""
],
[
"Wang",
"Tianhong",
""
],
[
"Jiang",
"Yue",
""
],
[
"Tan",
"Xiao-Ze",
""
],
[
"Li",
"Qiang",
""
],
[
"Wang",
"Guo-Li",
""
],
[
"Chang",
"Chao-Hsi",
""
]
] | In this paper, we systematically calculate two-body strong decays of newly observed $D_J(3000)$ and $D_{sJ}(3040)$ with 2P$(1^+)$ and 2P$(1^{+\prime})$ assignments in an instantaneous approximation of the Bethe-Salpeter equation method. Our results show that both resonances can be explained as the 2P$(1^{+'})$ with broad width via $^3P_1$ and $^1P_1$ mixing in $D$ and $D_s$ families. For $D_J(3000)$, the total width is 229.6 MeV in our calculation, close to the upper limit of experimental data, and the dominant decay channels are $D_2^*\pi$, $D^*\pi$, and $D^*(2600)\pi$. For $D_{sJ}(3040)$, the total width is 157.4 MeV in our calculation, close to the lower limit of experimental data, and the dominant channels are $D^*K$ and $D^*K^*$. These results are consistent with observed channels in experiments. Given the very little information that has been obtained from experiments and the large error bars of the total decay widths, we recommend the detection of dominant channels in our calculation. |
1711.03945 | Alexander Mitov | Michal Czakon, David Heymes, Alexander Mitov, Davide Pagani, Ioannis
Tsinikos, Marco Zaro | The top-quark charge asymmetry at the LHC and Tevatron through NNLO QCD
and NLO EW | 9 pages, 7 figures, 2 tables | Phys. Rev. D 98, 014003 (2018) | 10.1103/PhysRevD.98.014003 | Cavendish-HEP-17/13, CP3-17-46, NIKHEF/2017-59, TUM-HEP-1109/17,
TTK-17-37 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We provide the most up-to-date predictions for the top-quark charge asymmetry
A_C at the LHC with a centre-of-mass energy of 8 TeV. Our result is accurate at
the NNLO level in the strong interactions and at the complete-NLO level in both
the strong and electroweak interactions. We present results for the inclusive
A_C, several differential asymmetries as well as the P_{T,tt} and M_{tt}
cumulative asymmetries. Similarly to the Tevatron forward-backward asymmetry
A_FB, both NNLO QCD and NLO EW corrections to A_C are found to be significant.
The inclusion of higher-order corrections reduces the residual scale dependence
in the predicted A_C. The pattern of higher-order corrections indicates good
perturbative control over these observables. We conclude that at present there
is nearly uniform agreement between Standard Model predictions and LHC
measurements across all A_C-related observables. All previously published
differential A_FB predictions at the Tevatron are updated to the same accuracy.
| [
{
"created": "Fri, 10 Nov 2017 18:05:02 GMT",
"version": "v1"
}
] | 2018-07-11 | [
[
"Czakon",
"Michal",
""
],
[
"Heymes",
"David",
""
],
[
"Mitov",
"Alexander",
""
],
[
"Pagani",
"Davide",
""
],
[
"Tsinikos",
"Ioannis",
""
],
[
"Zaro",
"Marco",
""
]
] | We provide the most up-to-date predictions for the top-quark charge asymmetry A_C at the LHC with a centre-of-mass energy of 8 TeV. Our result is accurate at the NNLO level in the strong interactions and at the complete-NLO level in both the strong and electroweak interactions. We present results for the inclusive A_C, several differential asymmetries as well as the P_{T,tt} and M_{tt} cumulative asymmetries. Similarly to the Tevatron forward-backward asymmetry A_FB, both NNLO QCD and NLO EW corrections to A_C are found to be significant. The inclusion of higher-order corrections reduces the residual scale dependence in the predicted A_C. The pattern of higher-order corrections indicates good perturbative control over these observables. We conclude that at present there is nearly uniform agreement between Standard Model predictions and LHC measurements across all A_C-related observables. All previously published differential A_FB predictions at the Tevatron are updated to the same accuracy. |
hep-ph/0002222 | John R. Hiller | J.R. Hiller (University of Minnesota Duluth) | Pauli-Villars regularization and discrete light-cone quantization in
Yukawa theory | 6 pages; LaTeX, sprocl.sty; to appear in the proceedings of the CSSM
Workshop on Light-Cone QCD and Nonperturbative Hadron Physics, Adelaide,
Australia, December 13-21, 1999 | null | null | UMN-D-00-1 | hep-ph | null | The techniques of Pauli-Villars regularization and discrete light-cone
quantization are combined to analyze Yukawa theory in a single-fermion
truncation. A special form of the Lanczos algorithm is constructed for
diagonalization of the indefinite-metric light-cone Hamiltonian.
| [
{
"created": "Mon, 21 Feb 2000 17:42:15 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Hiller",
"J. R.",
"",
"University of Minnesota Duluth"
]
] | The techniques of Pauli-Villars regularization and discrete light-cone quantization are combined to analyze Yukawa theory in a single-fermion truncation. A special form of the Lanczos algorithm is constructed for diagonalization of the indefinite-metric light-cone Hamiltonian. |
0805.3300 | Alessandro Mirizzi | Basudeb Dasgupta, Amol Dighe (Tata Inst., Mumbai), Alessandro Mirizzi
(Munich, Max Planck Inst. & INFN, Italy), Georg G. Raffelt (Max Planck Inst.,
Munich) | Collective neutrino oscillations in non-spherical geometry | 14 pages, 6 eps figures | Phys.Rev.D78:033014,2008 | 10.1103/PhysRevD.78.033014 | MPP-2008-47, TIFR/TH/08-19 | hep-ph astro-ph math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The rich phenomenology of collective neutrino oscillations has been studied
only in one-dimensional or spherically symmetric systems. Motivated by the
non-spherical example of coalescing neutron stars, presumably the central
engines of short gamma-ray bursts, we use the Liouville equation to formulate
the problem for general source geometries. Assuming the neutrino ensemble
displays self-maintained coherence, the problem once more becomes effectively
one-dimensional along the streamlines of the overall neutrino flux. This
approach for the first time provides a formal definition of the ``single-angle
approximation'' frequently used for supernova neutrinos and allows for a
natural generalization to non-spherical geometries. We study the explicit
example of a disk-shaped source as a proxy for coalescing neutron stars.
| [
{
"created": "Wed, 21 May 2008 17:52:40 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Dasgupta",
"Basudeb",
"",
"Tata Inst., Mumbai"
],
[
"Dighe",
"Amol",
"",
"Tata Inst., Mumbai"
],
[
"Mirizzi",
"Alessandro",
"",
"Munich, Max Planck Inst. & INFN, Italy"
],
[
"Raffelt",
"Georg G.",
"",
"Max Planck Inst.,\n Munich"
]
] | The rich phenomenology of collective neutrino oscillations has been studied only in one-dimensional or spherically symmetric systems. Motivated by the non-spherical example of coalescing neutron stars, presumably the central engines of short gamma-ray bursts, we use the Liouville equation to formulate the problem for general source geometries. Assuming the neutrino ensemble displays self-maintained coherence, the problem once more becomes effectively one-dimensional along the streamlines of the overall neutrino flux. This approach for the first time provides a formal definition of the ``single-angle approximation'' frequently used for supernova neutrinos and allows for a natural generalization to non-spherical geometries. We study the explicit example of a disk-shaped source as a proxy for coalescing neutron stars. |
1911.04784 | Gabor Cynolter | A. Curko and G. Cynolter | Unitarity in Multi-Higgs Production | 12 pages, 6 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has long been known that perturbative calculations in scalar
multi-particle production could break down since fast growing amplitudes
appear. A recent calculation in the regime $ \lambda n \gg 1$, where $ n $ is
the multiplicity and $ \lambda $ is the self-coupling, gives an amplitude which
grows exponentially with the energy, resulting in a divergent propagator and
leading to the violation of perturbative unitarity. In this paper the
transition rate is calculated from the solution of the self-consistent
Schwinger-Dyson equation in spectral representation. We get an amplitude
growing quadratically with the energy which leads to an asymptotically
decreasing propagator contrary to previous results. Hence, unitarity is not
violated, as expected in the Standard Model.
| [
{
"created": "Tue, 12 Nov 2019 10:43:02 GMT",
"version": "v1"
}
] | 2019-11-13 | [
[
"Curko",
"A.",
""
],
[
"Cynolter",
"G.",
""
]
] | It has long been known that perturbative calculations in scalar multi-particle production could break down since fast growing amplitudes appear. A recent calculation in the regime $ \lambda n \gg 1$, where $ n $ is the multiplicity and $ \lambda $ is the self-coupling, gives an amplitude which grows exponentially with the energy, resulting in a divergent propagator and leading to the violation of perturbative unitarity. In this paper the transition rate is calculated from the solution of the self-consistent Schwinger-Dyson equation in spectral representation. We get an amplitude growing quadratically with the energy which leads to an asymptotically decreasing propagator contrary to previous results. Hence, unitarity is not violated, as expected in the Standard Model. |
1605.04280 | Zack Sullivan | Zack Sullivan | Boosted-bottom jet tagging and BSM searches | 4 pgs, 3 figs, Submission to Proceedings of the 51st Rencontres de
Moriond | null | null | IIT-CAPP-16-02 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I present a new scheme for tagging boosted heavy flavor jets called "$\mu_x$
tagging" and its application to TeV-scale physics beyond the Standard Model.
Using muons from B hadron decay to define a particular combination "x" of
angular information, and jet substructure variables, we identify a clean
($\epsilon_{\mathrm{fake}}/\epsilon_b\sim 1/100$) good efficiency ($\epsilon_b
= 14\%$) tag. I demonstrate the usefulness of this new scheme by showing the
reach for discovery of leptophobic $Z^\prime\to b\bar b$ and $tH^\pm\to t t b$.
| [
{
"created": "Fri, 13 May 2016 18:48:52 GMT",
"version": "v1"
}
] | 2016-05-16 | [
[
"Sullivan",
"Zack",
""
]
] | I present a new scheme for tagging boosted heavy flavor jets called "$\mu_x$ tagging" and its application to TeV-scale physics beyond the Standard Model. Using muons from B hadron decay to define a particular combination "x" of angular information, and jet substructure variables, we identify a clean ($\epsilon_{\mathrm{fake}}/\epsilon_b\sim 1/100$) good efficiency ($\epsilon_b = 14\%$) tag. I demonstrate the usefulness of this new scheme by showing the reach for discovery of leptophobic $Z^\prime\to b\bar b$ and $tH^\pm\to t t b$. |
0809.1324 | Dennis D. Dietrich | Dennis D. Dietrich and Chris Kouvaris | Generalised bottom-up holography and walking technicolour | 12 pages, 5 figures | Phys.Rev.D79:075004,2009 | 10.1103/PhysRevD.79.075004 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In extradimensional holographic approaches the flavour symmetry is gauged in
the bulk, that is, treated as a local symmetry. Imposing such a local symmetry
admits fewer terms coupling the (axial) vectors and (pseudo)scalars than if a
global symmetry is imposed. The latter is the case in standard low-energy
effective Lagrangians. Here we incorporate these additional, a priori only
globally invariant terms into a holographic treatment by means of a
Stueckelberg completion and alternatively by means of a Legendre
transformation. This work was motivated by our investigations concerning
dynamical electroweak symmetry breaking by walking technicolour and we apply
our findings to these theories.
| [
{
"created": "Mon, 8 Sep 2008 12:11:57 GMT",
"version": "v1"
}
] | 2009-04-22 | [
[
"Dietrich",
"Dennis D.",
""
],
[
"Kouvaris",
"Chris",
""
]
] | In extradimensional holographic approaches the flavour symmetry is gauged in the bulk, that is, treated as a local symmetry. Imposing such a local symmetry admits fewer terms coupling the (axial) vectors and (pseudo)scalars than if a global symmetry is imposed. The latter is the case in standard low-energy effective Lagrangians. Here we incorporate these additional, a priori only globally invariant terms into a holographic treatment by means of a Stueckelberg completion and alternatively by means of a Legendre transformation. This work was motivated by our investigations concerning dynamical electroweak symmetry breaking by walking technicolour and we apply our findings to these theories. |
hep-ph/9801234 | Hsin-Chia Cheng | Hsin-Chia Cheng (Fermilab) | Precision Supersymmetry Measurements at the e^-e^- Collider | 12 pages, 4 figures, LaTeX, Talk presented at the 2nd International
Workshop on Electron-Electron Interactions at TeV Energies, September 22-24,
1997, University of California, Santa Cruz | Int.J.Mod.Phys.A13:2329-2336,1998 | 10.1142/S0217751X98001116 | Fermilab-CONF-98/005-T | hep-ph | null | Measurements of supersymmetric particle couplings provide important
verification of supersymmetry. If some of the superpartners are at the
multi-TeV scale, they will escape direct detection at planned future colliders.
However, such particles induce nondecoupling corrections in processes involving
the accessible superparticles through violations of the supersymmetric
equivalence between gauge boson and gaugino couplings. These violations are
analogous to the oblique corrections in the electroweak sector of the standard
model, and can be parametrized in terms of super-oblique parameters. The $e^-
e^-$ collision mode of a future linear collider is shown to be an excellent
environment for such high precision measurements of these SUSY parameters,
which will provide an important probe of superparticles beyond reachable
energies.
| [
{
"created": "Wed, 7 Jan 1998 18:11:36 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Cheng",
"Hsin-Chia",
"",
"Fermilab"
]
] | Measurements of supersymmetric particle couplings provide important verification of supersymmetry. If some of the superpartners are at the multi-TeV scale, they will escape direct detection at planned future colliders. However, such particles induce nondecoupling corrections in processes involving the accessible superparticles through violations of the supersymmetric equivalence between gauge boson and gaugino couplings. These violations are analogous to the oblique corrections in the electroweak sector of the standard model, and can be parametrized in terms of super-oblique parameters. The $e^- e^-$ collision mode of a future linear collider is shown to be an excellent environment for such high precision measurements of these SUSY parameters, which will provide an important probe of superparticles beyond reachable energies. |
hep-ph/0006110 | Huo Wu-jun | Wu-Jun Huo (IHEP, Cas, P.R.China) | Effects of the Fourth Generation on $\Delta M_{B_{d,s}}$ in $B^0-\bar
B^0$ Mixing | 13 pages, 5 figures. accepted by Europ. Phys. Jour. C | Eur.Phys.J.C24:275-280,2002 | 10.1007/s100520200933 | null | hep-ph | null | We investigate the mass differences $\Delta M_{B_{d,s}}$ in the mixing
$B^0_{d,s}-\bar B^0_{d,s}$ with a new up-like quark $t^{\prime}$ in the
sequential fourth generation model. We give the basic formulae for $\Delta
M_{B_{d,s}}$ in this model and obtain two kinds of numerical results of $\Delta
M_{B_{s}}$ which is the function of $m_{t^{\prime}}$. We find that one of our
results can satisfy the present experimental low bound of $\Delta M_{B_s}$. We
also get the constraints of the fourth generation CKM factor
$V^{*}_{t^{'}b}V_{t^{'}d}$, which is the function of $t^{'}$, from the
experimental measurements of $\Delta M_{B_d}$. Thus, $\Delta M_{B_{d,s}}$
provide a possible test of the fourth generation and give a signal of the new
physics.
| [
{
"created": "Mon, 12 Jun 2000 07:21:23 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Aug 2000 16:02:16 GMT",
"version": "v2"
},
{
"created": "Tue, 4 Dec 2001 03:36:33 GMT",
"version": "v3"
},
{
"created": "Wed, 20 Mar 2002 14:13:31 GMT",
"version": "v4"
}
] | 2008-11-26 | [
[
"Huo",
"Wu-Jun",
"",
"IHEP, Cas, P.R.China"
]
] | We investigate the mass differences $\Delta M_{B_{d,s}}$ in the mixing $B^0_{d,s}-\bar B^0_{d,s}$ with a new up-like quark $t^{\prime}$ in the sequential fourth generation model. We give the basic formulae for $\Delta M_{B_{d,s}}$ in this model and obtain two kinds of numerical results of $\Delta M_{B_{s}}$ which is the function of $m_{t^{\prime}}$. We find that one of our results can satisfy the present experimental low bound of $\Delta M_{B_s}$. We also get the constraints of the fourth generation CKM factor $V^{*}_{t^{'}b}V_{t^{'}d}$, which is the function of $t^{'}$, from the experimental measurements of $\Delta M_{B_d}$. Thus, $\Delta M_{B_{d,s}}$ provide a possible test of the fourth generation and give a signal of the new physics. |
1507.08812 | Emanuele Messina | Vincenzo Branchina and Emanuele Messina | Stability and UV completion of the Standard Model | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The knowledge of the stability condition of the electroweak (EW) vacuum is of
the greatest importance for our understanding of beyond Standard Model (BSM)
physics. It is widely believed that new physics that lives at very high energy
scales should have no impact on the stability analysis. This expectation has
been recently challenged, but the results were controversial as new physics was
given in terms of non-renormalizable higher order operators. Here we consider
for the first time a renormalizable (toy) UV completion of the SM, and
definitely show that such a decoupling does not take place. This result has
important phenomenological consequences, providing a very useful test for BSM
theories. In particular, it shows that speculations based on the so called
"criticality" do not appear to be well founded.
| [
{
"created": "Fri, 31 Jul 2015 09:45:34 GMT",
"version": "v1"
}
] | 2015-08-03 | [
[
"Branchina",
"Vincenzo",
""
],
[
"Messina",
"Emanuele",
""
]
] | The knowledge of the stability condition of the electroweak (EW) vacuum is of the greatest importance for our understanding of beyond Standard Model (BSM) physics. It is widely believed that new physics that lives at very high energy scales should have no impact on the stability analysis. This expectation has been recently challenged, but the results were controversial as new physics was given in terms of non-renormalizable higher order operators. Here we consider for the first time a renormalizable (toy) UV completion of the SM, and definitely show that such a decoupling does not take place. This result has important phenomenological consequences, providing a very useful test for BSM theories. In particular, it shows that speculations based on the so called "criticality" do not appear to be well founded. |
1011.4839 | Keisho Hidaka | A. Bartl (1), H. Eberl (2), B. Herrmann (3), K. Hidaka (4), K.
Hohenwarter-Sodek (1), T. Kernreiter (1), W. Majerotto (2) and W. Porod (5)
((1) Vienna U., (2) IHEP, Vienna, (3) DESY, (4) Tokyo Gakugei U., (5)
Wurzburg U.) | Impact of squark generation mixing on the search for squarks and gluinos
at LHC | 5 pages, 3 figures, Proceedings of the 35th International Conference
of High Energy Physics (ICHEP2010), Paris, France, July 22-28, 2010, file
error corrected | Proceedings of the 35th International Conference of High Energy
Physics, PoS(ICHEP 2010)395 | null | DESY 10-202 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the effect of squark-generation mixing on production and decays of
squarks and gluinos at LHC in the Minimal Supersymmetric Standard Model (MSSM).
We show that the mixing effects can be very large in a significant range of the
squark-generation mixing parameters despite the very strong constraints on
quark-flavour violation (QFV) from experimental data on B mesons. We find that
under favourable conditions the QFV decay branching ratio B(gluino -> c bar{t}
(t bar{c}) neutralino_1) can be as large as about 50%, which may lead to
significant QFV signals at LHC. We also find that the squark generation mixing
can result in a novel multiple-edge (3- or 4-edge) structure in the charm-top
quark invariant mass distribution. Further we show that the two lightest
up-type squarks ~u_{1,2} can have very large branching ratios for the decays
~u_i -> c neutralino_1 and ~u_i -> t neutralino_1 simultaneously due to the
mixing effect, resulting in QFV signals 'pp -> c bar{t} (t bar{c}) +
missing-E_T + X' at a significant rate at LHC. These remarkable signatures
could provide a powerful test of supersymmetric QFV at LHC and could have an
important impact on the search for squarks and gluinos and the determination of
the MSSM parameters at LHC.
| [
{
"created": "Mon, 22 Nov 2010 15:09:15 GMT",
"version": "v1"
},
{
"created": "Fri, 31 Dec 2010 03:58:06 GMT",
"version": "v2"
}
] | 2011-01-04 | [
[
"Bartl",
"A.",
""
],
[
"Eberl",
"H.",
""
],
[
"Herrmann",
"B.",
""
],
[
"Hidaka",
"K.",
""
],
[
"Hohenwarter-Sodek",
"K.",
""
],
[
"Kernreiter",
"T.",
""
],
[
"Majerotto",
"W.",
""
],
[
"Porod",
"W.",
""
]
] | We study the effect of squark-generation mixing on production and decays of squarks and gluinos at LHC in the Minimal Supersymmetric Standard Model (MSSM). We show that the mixing effects can be very large in a significant range of the squark-generation mixing parameters despite the very strong constraints on quark-flavour violation (QFV) from experimental data on B mesons. We find that under favourable conditions the QFV decay branching ratio B(gluino -> c bar{t} (t bar{c}) neutralino_1) can be as large as about 50%, which may lead to significant QFV signals at LHC. We also find that the squark generation mixing can result in a novel multiple-edge (3- or 4-edge) structure in the charm-top quark invariant mass distribution. Further we show that the two lightest up-type squarks ~u_{1,2} can have very large branching ratios for the decays ~u_i -> c neutralino_1 and ~u_i -> t neutralino_1 simultaneously due to the mixing effect, resulting in QFV signals 'pp -> c bar{t} (t bar{c}) + missing-E_T + X' at a significant rate at LHC. These remarkable signatures could provide a powerful test of supersymmetric QFV at LHC and could have an important impact on the search for squarks and gluinos and the determination of the MSSM parameters at LHC. |
1905.08784 | Dong-Yang Wang | Dong-Yang Wang, Ya-Dong Yang, and Xing-Bo Yuan | $b \to c\tau\bar\nu$ decays in supersymmetry with $R$-parity violation | 32 pages, 5 figures, to be published in Chinese Physics C. arXiv
admin note: text overlap with arXiv:1905.01795 | Chinese Physics C Vol.43, No.8(2019)083103 | 10.1088/1674-1137/43/8/083103 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the past few years, several hints of lepton flavour universality (LFU)
violation have emerged in the $b \to c \tau \bar\nu$ and $b \to s \ell^+
\ell^-$ data. Quite recently, the Belle Collaboration has reported the first
measurement of the $D^*$ longitudinal polarization fraction in the $B \to D^*
\tau \bar\nu$ decay. Motivated by this intriguing result, together with the
recent measurements of $R_{J/\psi}$ and $\tau$ polarization, we study $b \to c
\tau \bar\nu$ decays in the Supersymmetry (SUSY) with $R$-parity violation
(RPV). We consider $B \to D^{(*)} \tau \bar\nu$, $B_c \to \eta_c \tau \bar\nu$,
$B_c \to J/\psi \tau \bar\nu$ and $\Lambda_b \to \Lambda_c \tau \bar\nu$ modes
and focus on the branching ratios, the LFU ratios, the forward-backward
asymmetries, polarizations of daughter hadrons and $\tau$ lepton. It is found
that the RPV SUSY can explain the $R_{D^{(*)}}$ anomalies at $2\sigma$ level,
after taking into account various flavour constraints. In the allowed parameter
space, the differential branching fractions and LFU ratios are largely enhanced
by the SUSY effects, especially in the large dilepton invariant mass region. In
addition, a lower bound $\mathcal B(B^+ \to K^+ \nu \bar\nu) > 7.37 \times
10^{-6}$ is obtained. These observables could provide testable signatures at
the High-Luminosity LHC and SuperKEKB, and correlate with direct searches for
SUSY.
| [
{
"created": "Tue, 21 May 2019 02:21:23 GMT",
"version": "v1"
}
] | 2019-07-23 | [
[
"Wang",
"Dong-Yang",
""
],
[
"Yang",
"Ya-Dong",
""
],
[
"Yuan",
"Xing-Bo",
""
]
] | In the past few years, several hints of lepton flavour universality (LFU) violation have emerged in the $b \to c \tau \bar\nu$ and $b \to s \ell^+ \ell^-$ data. Quite recently, the Belle Collaboration has reported the first measurement of the $D^*$ longitudinal polarization fraction in the $B \to D^* \tau \bar\nu$ decay. Motivated by this intriguing result, together with the recent measurements of $R_{J/\psi}$ and $\tau$ polarization, we study $b \to c \tau \bar\nu$ decays in the Supersymmetry (SUSY) with $R$-parity violation (RPV). We consider $B \to D^{(*)} \tau \bar\nu$, $B_c \to \eta_c \tau \bar\nu$, $B_c \to J/\psi \tau \bar\nu$ and $\Lambda_b \to \Lambda_c \tau \bar\nu$ modes and focus on the branching ratios, the LFU ratios, the forward-backward asymmetries, polarizations of daughter hadrons and $\tau$ lepton. It is found that the RPV SUSY can explain the $R_{D^{(*)}}$ anomalies at $2\sigma$ level, after taking into account various flavour constraints. In the allowed parameter space, the differential branching fractions and LFU ratios are largely enhanced by the SUSY effects, especially in the large dilepton invariant mass region. In addition, a lower bound $\mathcal B(B^+ \to K^+ \nu \bar\nu) > 7.37 \times 10^{-6}$ is obtained. These observables could provide testable signatures at the High-Luminosity LHC and SuperKEKB, and correlate with direct searches for SUSY. |
hep-ph/9703205 | null | V. B. Kopeliovich (INR, Moscow, Russia) | Strange dibaryons in the Skyrme model | 6 pages, no figures; the talk at the Workshop on Hypernuclear Physics
(25th INS Symposium), December 7-8, Tokyo, Japan. To be published in
"Genshikaku Kenkyu" (Nuclear Studies) | Genshikaku Kenkyu 41:171-176,1997 | null | null | hep-ph | null | The phenomenological consequences of the existence of different local minima
in SU(3) configuration space of B=2 skyrmions are discussed.
| [
{
"created": "Fri, 28 Feb 1997 12:35:42 GMT",
"version": "v1"
}
] | 2011-04-15 | [
[
"Kopeliovich",
"V. B.",
"",
"INR, Moscow, Russia"
]
] | The phenomenological consequences of the existence of different local minima in SU(3) configuration space of B=2 skyrmions are discussed. |
hep-ph/9710462 | Gerhard Schuler | G.A. Schuler, F.A. Berends, R. van Gulik | Meson--photon transition form factors and resonance cross-sections in
e^+ e^- collisions | 17 pages, Latex, 4 figures | Nucl.Phys. B523 (1998) 423-438 | 10.1016/S0550-3213(98)00128-X | CERN-TH/97-294 | hep-ph | null | Meson--photon--photon transition form factors for S-, P-, and D-wave states
are calculated, the meson being treated as a non-relativistic
heavy-quark--antiquark pair. The full dependence on both photon virtualities is
included. Cross-section formulas for charge-conjugation even mesons with J^P =
0^-, 0^+, 1^+, 2^+, and 2^- in electron--positron collisions are presented and
numerical results for LEP energies are given. In particular, we find two-photon
event rates for \chi_{\rc 1}, \eta_{\rc}(2S), and \eta_{\rb}(1S) within reach
of LEP.
With minor modifications to incorporate SU(3)-flavour breaking we estimate
rates for 18 light mesons as well, based on the observation that their
two-photon decay widths agree remarkably well with measured data. Finally we
point out that e^+ e^- cross sections for 1^+ states do not vanish at low Q^2,
the Landau--Yang suppression factors of the two-photon cross sections being
compensated by the photon propagators.
| [
{
"created": "Fri, 24 Oct 1997 17:07:04 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Schuler",
"G. A.",
""
],
[
"Berends",
"F. A.",
""
],
[
"van Gulik",
"R.",
""
]
] | Meson--photon--photon transition form factors for S-, P-, and D-wave states are calculated, the meson being treated as a non-relativistic heavy-quark--antiquark pair. The full dependence on both photon virtualities is included. Cross-section formulas for charge-conjugation even mesons with J^P = 0^-, 0^+, 1^+, 2^+, and 2^- in electron--positron collisions are presented and numerical results for LEP energies are given. In particular, we find two-photon event rates for \chi_{\rc 1}, \eta_{\rc}(2S), and \eta_{\rb}(1S) within reach of LEP. With minor modifications to incorporate SU(3)-flavour breaking we estimate rates for 18 light mesons as well, based on the observation that their two-photon decay widths agree remarkably well with measured data. Finally we point out that e^+ e^- cross sections for 1^+ states do not vanish at low Q^2, the Landau--Yang suppression factors of the two-photon cross sections being compensated by the photon propagators. |
1710.09197 | Jiaxing Zhao | Jiaxing Zhao and Pengfei Zhuang | Exotic Quantum States for Charmed Baryons at Finite Temperature | null | null | 10.1016/j.physletb.2017.10.057 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The significantly screened heavy-quark potential in hot medium provides the
possibility to study exotic quantum states of three-heavy-quark systems. By
solving the Schr\"odinger equation for a three-charm-quark system at finite
temperature, we found that, there exist Borromean states which might be
realized in high energy nuclear collisions, and the binding energies of the
system satisfy precisely the scaling law for Efimov states in the resonance
limit.
| [
{
"created": "Wed, 25 Oct 2017 12:41:01 GMT",
"version": "v1"
}
] | 2017-11-22 | [
[
"Zhao",
"Jiaxing",
""
],
[
"Zhuang",
"Pengfei",
""
]
] | The significantly screened heavy-quark potential in hot medium provides the possibility to study exotic quantum states of three-heavy-quark systems. By solving the Schr\"odinger equation for a three-charm-quark system at finite temperature, we found that, there exist Borromean states which might be realized in high energy nuclear collisions, and the binding energies of the system satisfy precisely the scaling law for Efimov states in the resonance limit. |
hep-ph/0009153 | Klaus Werner | K. Werner | Tools for RHIC: Review of Models | Invited talk given at the 5th International Conference on Strangeness
in Quark Matter | J.Phys.G27:625-634,2001 | 10.1088/0954-3899/27/3/347 | SUBATECH 00-12 | hep-ph nucl-ex nucl-th | null | We discuss the present status of microscopic models for RHIC, with an
emphasis on models being realized via the Monte Carlo technique. This review is
to a large extent based on the OSCAR3 workshop, where general concepts and new
trends in this field have been discussed.
| [
{
"created": "Wed, 13 Sep 2000 12:46:39 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Werner",
"K.",
""
]
] | We discuss the present status of microscopic models for RHIC, with an emphasis on models being realized via the Monte Carlo technique. This review is to a large extent based on the OSCAR3 workshop, where general concepts and new trends in this field have been discussed. |
1611.06006 | Vladimir Kuksa | V. Beylin, M. Bezuglov, V. Kuksa, N. Volchanskiy | An analysis of a minimal vectorlike extension of the Standard Model | 16 pages, 1 table, v.2: minor modification, reference is added,
formula (62) is corrected | Adv. in High Energy Phys., vol. 2017, ID 1765340, 14 pages (2017) | 10.1155/2017/1765340 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze an extension of the Standard Model with an additional SU(2)
hypercolor gauge group keeping the Higgs boson as a fundamental field.
Vectorlike interactions of new hyperquarks with the intermediate vector bosons
are explicitly constructed. We also consider pseudo-Nambu--Goldstone bosons
caused by the symmetry breaking SU(4)-> Sp(4). A specific global symmetry of
the model with zero hypercharge of the hyperquark doublets ensures the
stability of a neutral pseudoscalar field. Some possible manifestations of the
lightest states at colliders are also examined.
| [
{
"created": "Fri, 18 Nov 2016 08:38:56 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Jan 2017 09:16:44 GMT",
"version": "v2"
},
{
"created": "Thu, 25 May 2017 09:36:10 GMT",
"version": "v3"
}
] | 2017-07-11 | [
[
"Beylin",
"V.",
""
],
[
"Bezuglov",
"M.",
""
],
[
"Kuksa",
"V.",
""
],
[
"Volchanskiy",
"N.",
""
]
] | We analyze an extension of the Standard Model with an additional SU(2) hypercolor gauge group keeping the Higgs boson as a fundamental field. Vectorlike interactions of new hyperquarks with the intermediate vector bosons are explicitly constructed. We also consider pseudo-Nambu--Goldstone bosons caused by the symmetry breaking SU(4)-> Sp(4). A specific global symmetry of the model with zero hypercharge of the hyperquark doublets ensures the stability of a neutral pseudoscalar field. Some possible manifestations of the lightest states at colliders are also examined. |
hep-ph/0007277 | Carsten Vogt | Carsten Vogt | Skewed parton distributions and the scale dependence of the transverse
size parameter | 10 pages, 4 figures; version to appear in Phys. Rev. D; Refs. added,
new discussion of results for pion form factor in view of new data | Phys.Rev.D63:034013,2001 | 10.1103/PhysRevD.63.034013 | WU B 00-15 | hep-ph | null | We discuss the scale dependence of a skewed parton distribution of the pion
obtained from a generalized light-cone wave function overlap formula. Using a
simple ansatz for the transverse momentum dependence of the light-cone wave
function and restricting ourselves to the case of a zero skewedness parameter,
the skewed parton distribution can be expressed through an ordinary parton
distribution multiplied by an exponential function. Matching the generalized
and ordinary DGLAP evolution equations of the skewed and ordinary parton
distributions, respectively, we derive a constraint for the scale dependence of
the transverse size parameter, which describes the width of the pion wave
function in transverse momentum space. This constraint has implications for the
Fock state probability and valence distribution. We apply our results to the
pion form factor.
| [
{
"created": "Tue, 25 Jul 2000 12:18:38 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Nov 2000 15:48:47 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Vogt",
"Carsten",
""
]
] | We discuss the scale dependence of a skewed parton distribution of the pion obtained from a generalized light-cone wave function overlap formula. Using a simple ansatz for the transverse momentum dependence of the light-cone wave function and restricting ourselves to the case of a zero skewedness parameter, the skewed parton distribution can be expressed through an ordinary parton distribution multiplied by an exponential function. Matching the generalized and ordinary DGLAP evolution equations of the skewed and ordinary parton distributions, respectively, we derive a constraint for the scale dependence of the transverse size parameter, which describes the width of the pion wave function in transverse momentum space. This constraint has implications for the Fock state probability and valence distribution. We apply our results to the pion form factor. |
hep-ph/0312146 | Igor Machulin | I.N. Machulin, S.V. Tolokonnikov | Neutrino flavour relaxation or neutrino oscillations? | null | JETP Lett. 79 (2004) 249-252; Pisma Zh.Eksp.Teor.Fiz. 79 (2004)
307-310 | 10.1134/1.1759403 | null | hep-ph | null | We propose the new mechanism of neutrino flavour relaxation to explain the
experimentally observed changes of initial neutrino flavour fluxes. The test of
neutrino relaxation hypothesis is presented, using the data of modern reactor,
solar and accelerator experiments. The final choice between the standard
neutrino oscillations and the proposed neutrino flavour relaxation model can be
done in future experiments.
| [
{
"created": "Thu, 11 Dec 2003 00:13:47 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Machulin",
"I. N.",
""
],
[
"Tolokonnikov",
"S. V.",
""
]
] | We propose the new mechanism of neutrino flavour relaxation to explain the experimentally observed changes of initial neutrino flavour fluxes. The test of neutrino relaxation hypothesis is presented, using the data of modern reactor, solar and accelerator experiments. The final choice between the standard neutrino oscillations and the proposed neutrino flavour relaxation model can be done in future experiments. |
2306.13280 | Joseph Kapusta | Joseph I. Kapusta, Scott Pratt and Mayank Singh | Disoriented isospin condensates may be the source of anomalous kaon
correlations measured in Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV | 5 pages, 4 figures | Phys. Rev. C 109, L031902 (2024) | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The magnitude of fluctuations between charged and neutral kaons measured by
the ALICE Collaboration in heavy-ion collisions at the LHC exceeds conventional
explanation. Here it is shown that if the scalar condensate, which is typically
associated with chiral symmetry, is accompanied by an isospin=1 field, then the
combination can produce large fluctuations where $\langle \bar{u}u\rangle \ne
\langle \bar{d}d\rangle$. Hadronizing strange and anti-strange quarks might
then strongly fluctuate between charged ($u\bar{s}$ or $s\bar{u}$) and neutral
($d\bar{s}$ or $s\bar{d}$) kaons.
| [
{
"created": "Fri, 23 Jun 2023 03:47:39 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Mar 2024 03:56:17 GMT",
"version": "v2"
}
] | 2024-03-15 | [
[
"Kapusta",
"Joseph I.",
""
],
[
"Pratt",
"Scott",
""
],
[
"Singh",
"Mayank",
""
]
] | The magnitude of fluctuations between charged and neutral kaons measured by the ALICE Collaboration in heavy-ion collisions at the LHC exceeds conventional explanation. Here it is shown that if the scalar condensate, which is typically associated with chiral symmetry, is accompanied by an isospin=1 field, then the combination can produce large fluctuations where $\langle \bar{u}u\rangle \ne \langle \bar{d}d\rangle$. Hadronizing strange and anti-strange quarks might then strongly fluctuate between charged ($u\bar{s}$ or $s\bar{u}$) and neutral ($d\bar{s}$ or $s\bar{d}$) kaons. |
1311.6815 | Sylvain Fichet | Sylvain Fichet, Gero von Gersdorff | Anomalous gauge couplings from composite Higgs and warped extra
dimensions | 37 pages, 2 figures, 3 tables. Minor typos fixed, some comments and
references added. Matches JHEP version | null | 10.1007/JHEP03(2014)102 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine trilinear and quartic anomalous gauge couplings (AGCs) generated
in composite Higgs models and models with warped extra dimensions. We first
revisit the SU(2)_L x U(1)_Y effective Lagrangian and derive the charged and
two-photon neutral AGCs. We derive the general perturbative contributions to
the pure field-strength operators from spin 0, 1/2, 1 resonances by means of
the heat kernel method. In the composite Higgs framework, we derive the pattern
of expected deviations from typical SO(N) embeddings of the light composite top
partner. We then study a generic warped extra dimension framework with AdS_5
background, recasting in few parameters the features of models relevant for
AGCs. We also present a detailed study of the latest bounds from electroweak
and Higgs precision observables, with and without brane kinetic terms. For
vanishing brane kinetic terms, we find that the S and T parameters exclude KK
gauge modes of the RS custodial [non-custodial] scenario below 7.7 [14.7] TeV,
for a brane Higgs and below 6.6 [8.1] TeV for a Pseudo Nambu-Goldstone Higgs,
at 95% CL. These constraints can be relaxed in presence of brane kinetic terms.
The leading AGCs are probing the KK gravitons and the KK modes of bulk gauge
fields in parts of the parameter space. In these scenarios, the future CMS and
ATLAS forward proton detectors could be sensitive to the effect of KK gravitons
in the multi-TeV mass range.
| [
{
"created": "Tue, 26 Nov 2013 21:00:06 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Mar 2014 14:37:14 GMT",
"version": "v2"
}
] | 2015-06-18 | [
[
"Fichet",
"Sylvain",
""
],
[
"von Gersdorff",
"Gero",
""
]
] | We examine trilinear and quartic anomalous gauge couplings (AGCs) generated in composite Higgs models and models with warped extra dimensions. We first revisit the SU(2)_L x U(1)_Y effective Lagrangian and derive the charged and two-photon neutral AGCs. We derive the general perturbative contributions to the pure field-strength operators from spin 0, 1/2, 1 resonances by means of the heat kernel method. In the composite Higgs framework, we derive the pattern of expected deviations from typical SO(N) embeddings of the light composite top partner. We then study a generic warped extra dimension framework with AdS_5 background, recasting in few parameters the features of models relevant for AGCs. We also present a detailed study of the latest bounds from electroweak and Higgs precision observables, with and without brane kinetic terms. For vanishing brane kinetic terms, we find that the S and T parameters exclude KK gauge modes of the RS custodial [non-custodial] scenario below 7.7 [14.7] TeV, for a brane Higgs and below 6.6 [8.1] TeV for a Pseudo Nambu-Goldstone Higgs, at 95% CL. These constraints can be relaxed in presence of brane kinetic terms. The leading AGCs are probing the KK gravitons and the KK modes of bulk gauge fields in parts of the parameter space. In these scenarios, the future CMS and ATLAS forward proton detectors could be sensitive to the effect of KK gravitons in the multi-TeV mass range. |
1912.03835 | Rusa Mandal | Rusa Mandal | Angular analysis of $\bar{B}\to D_2^*(\to D \pi)\ell \bar{\nu}$ decay
and new physics | Matches with the published version | Phys. Rev. D 101, 033007 (2020) | 10.1103/PhysRevD.101.033007 | SI-HEP-2019-18 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive the four-fold angular distribution for the semileptonic decay
$\bar{B}\to D_2^*(\to D \pi)\,\ell \bar{\nu}$ where $D_2^*$(2460) is a tensor
meson. We start with the most general beyond the Standard Model (SM)
dimension-six effective Hamiltonian which comprises (axial)vector,
(pseudo)scalar and tensor operators for both quark and lepton currents, and it
also includes the right-handed neutrinos. The decay can be described by 16
transversity amplitudes and it provides a multitude of observables which can be
extracted from data. We investigate the observables in the context of the SM
and the new physics scenarios which can explain the intriguing discrepancies
observed in the $b \to c \tau \bar{\nu}$ data.
| [
{
"created": "Mon, 9 Dec 2019 03:54:24 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Feb 2020 15:54:29 GMT",
"version": "v2"
}
] | 2020-02-26 | [
[
"Mandal",
"Rusa",
""
]
] | We derive the four-fold angular distribution for the semileptonic decay $\bar{B}\to D_2^*(\to D \pi)\,\ell \bar{\nu}$ where $D_2^*$(2460) is a tensor meson. We start with the most general beyond the Standard Model (SM) dimension-six effective Hamiltonian which comprises (axial)vector, (pseudo)scalar and tensor operators for both quark and lepton currents, and it also includes the right-handed neutrinos. The decay can be described by 16 transversity amplitudes and it provides a multitude of observables which can be extracted from data. We investigate the observables in the context of the SM and the new physics scenarios which can explain the intriguing discrepancies observed in the $b \to c \tau \bar{\nu}$ data. |
1801.04604 | Franz Himpsel | F. J. Himpsel | Dynamical Symmetry Breaking by SU(2) Gauge Bosons | 17 pages, 2 figures. Versions 2,3: added Ref. [15], augmented
Appendix B, clarified the text. Versions 4,5: added Eq. (35) + text (formula
for g), generalized Eq. (B17) + text | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This work explores the possibility of obtaining a mass gap in Yang-Mills
theories via the intrinsic gauge bosons, without invoking a separate Higgs
boson or fermion-antifermion pairs. Instead, pairs of gauge bosons in the spin
and isospin singlet state form a pair of composite Higgs bosons which can be
viewed as the simplest possible glueball of Yang-Mills gauge theories.
Quadratic and quartic gauge boson self-interactions form a potential that leads
to a finite expectation value of the gauge boson amplitude. Transverse
polarization ensures Lorentz invariance of the vacuum after averaging over all
possible polarization vectors. But the scalar pair products exhibit a finite
vacuum expectation value which breaks the gauge symmetry dynamically.
Compatibility with the standard Higgs potential determines the quadratic and
quartic coupling constants.
| [
{
"created": "Sun, 14 Jan 2018 19:38:59 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Jan 2018 13:44:30 GMT",
"version": "v2"
},
{
"created": "Wed, 21 Feb 2018 16:26:44 GMT",
"version": "v3"
},
{
"created": "Sun, 11 Mar 2018 16:39:39 GMT",
"version": "v4"
},
{
"created": "Wed, 9 May 2018 14:44:57 GMT",
"version": "v5"
}
] | 2018-05-10 | [
[
"Himpsel",
"F. J.",
""
]
] | This work explores the possibility of obtaining a mass gap in Yang-Mills theories via the intrinsic gauge bosons, without invoking a separate Higgs boson or fermion-antifermion pairs. Instead, pairs of gauge bosons in the spin and isospin singlet state form a pair of composite Higgs bosons which can be viewed as the simplest possible glueball of Yang-Mills gauge theories. Quadratic and quartic gauge boson self-interactions form a potential that leads to a finite expectation value of the gauge boson amplitude. Transverse polarization ensures Lorentz invariance of the vacuum after averaging over all possible polarization vectors. But the scalar pair products exhibit a finite vacuum expectation value which breaks the gauge symmetry dynamically. Compatibility with the standard Higgs potential determines the quadratic and quartic coupling constants. |
1303.5351 | Lingfei Wang | Lingfei Wang, Ernestas Pukartas and Anupam Mazumdar | Visible sector inflation and the right thermal history in light of
Planck data | 24 pages, 9 figures, revision accepted by JCAP | JCAP 1307 (2013) 019 | 10.1088/1475-7516/2013/07/019 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inflation creates perturbations for the large scale structures in the
universe, but it also dilutes everything. Therefore it is pertinent that the
end of inflation must explain how to excite the Standard Model {\it dof} along
with the dark matter. In this paper we will briefly discuss the role of visible
sector inflaton candidates which are embedded within the Minimal Supersymmetric
Standard Model (MSSM) and discuss their merit on how well they match the
current data from the Planck. Since the inflaton carries the Standard Model
charges their decay naturally produces all the relevant {\it dof} with no {\it
dark/hidden sector radiation} and no isocurvature fluctuations. We will first
discuss a single supersymmetric flat direction model of inflation and
demonstrate what parameter space is allowed by the Planck and the LHC. We will
also consider where the perturbations are created by another light field which
decays after inflation, known as a {\it curvaton}. The late decay of the
curvaton can create observable non-Gaussianity. In the end we will discuss the
role of a {\it spectator} field whose origin may not lie within the visible
sector physics, but its sheer presence during inflation can still create all
the perturbations responsible for the large scale structures including possible
non-Gaussianity, while the inflaton is embedded within the visible sector which
creates all the relevant matter including dark matter, but no dark radiation.
| [
{
"created": "Thu, 21 Mar 2013 17:56:52 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Jun 2013 15:33:58 GMT",
"version": "v2"
}
] | 2013-07-22 | [
[
"Wang",
"Lingfei",
""
],
[
"Pukartas",
"Ernestas",
""
],
[
"Mazumdar",
"Anupam",
""
]
] | Inflation creates perturbations for the large scale structures in the universe, but it also dilutes everything. Therefore it is pertinent that the end of inflation must explain how to excite the Standard Model {\it dof} along with the dark matter. In this paper we will briefly discuss the role of visible sector inflaton candidates which are embedded within the Minimal Supersymmetric Standard Model (MSSM) and discuss their merit on how well they match the current data from the Planck. Since the inflaton carries the Standard Model charges their decay naturally produces all the relevant {\it dof} with no {\it dark/hidden sector radiation} and no isocurvature fluctuations. We will first discuss a single supersymmetric flat direction model of inflation and demonstrate what parameter space is allowed by the Planck and the LHC. We will also consider where the perturbations are created by another light field which decays after inflation, known as a {\it curvaton}. The late decay of the curvaton can create observable non-Gaussianity. In the end we will discuss the role of a {\it spectator} field whose origin may not lie within the visible sector physics, but its sheer presence during inflation can still create all the perturbations responsible for the large scale structures including possible non-Gaussianity, while the inflaton is embedded within the visible sector which creates all the relevant matter including dark matter, but no dark radiation. |
1805.09296 | Vladimir Skokov | Alex Kovner, Vladimir V. Skokov | Bose enhancement, the Liouville effective action and the high
multiplicity tail in p-A collisions | 15 pages, 3 figures; version accepted for publication | Phys. Rev. D 98, 014004 (2018) | 10.1103/PhysRevD.98.014004 | CERN-TH-2018-101, RBRC-1281 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of dense-dilute CGC approach we study fluctuations in the
multiplicity of produced particles in p-A collisions. We show that the leading
effect that drives the fluctuations is the Bose enhancement of gluons in the
proton wave function. We explicitly calculate the moment generating function
that resums the effects of Bose enhancement. We show that it can be understood
in terms of the Liouville effective action for the composite field which is
identified with the fluctuating density, or saturation momentum of the proton.
The resulting probability distribution turns out to be very close to the
gamma-distribution. We also calculate the first correction to this distribution
which is due to pairwise Hanbury Brown-Twiss correlations of produced gluons.
| [
{
"created": "Wed, 23 May 2018 17:34:02 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Jan 2019 19:24:23 GMT",
"version": "v2"
}
] | 2019-01-16 | [
[
"Kovner",
"Alex",
""
],
[
"Skokov",
"Vladimir V.",
""
]
] | In the framework of dense-dilute CGC approach we study fluctuations in the multiplicity of produced particles in p-A collisions. We show that the leading effect that drives the fluctuations is the Bose enhancement of gluons in the proton wave function. We explicitly calculate the moment generating function that resums the effects of Bose enhancement. We show that it can be understood in terms of the Liouville effective action for the composite field which is identified with the fluctuating density, or saturation momentum of the proton. The resulting probability distribution turns out to be very close to the gamma-distribution. We also calculate the first correction to this distribution which is due to pairwise Hanbury Brown-Twiss correlations of produced gluons. |
1711.03988 | Soubhik Kumar | Soubhik Kumar and Raman Sundrum | Heavy-Lifting of Gauge Theories By Cosmic Inflation | 53 pages, 12 figures | JHEP 1805 (2018) 011 | 10.1007/JHEP05(2018)011 | UMD-PP-017-31 | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Future measurements of primordial non-Gaussianity can reveal cosmologically
produced particles with masses of order the inflationary Hubble scale and their
interactions with the inflaton, giving us crucial insights into the structure
of fundamental physics at extremely high energies. We study gauge-Higgs
theories that may be accessible in this regime, carefully imposing the
constraints of gauge symmetry and its (partial) Higgsing. We distinguish two
types of Higgs mechanisms: (i) a standard one in which the Higgs scale is
constant before and after inflation, where the particles observable in
non-Gaussianities are far heavier than can be accessed by laboratory
experiments, perhaps associated with gauge unification, and (ii) a
"heavy-lifting" mechanism in which couplings to curvature can result in Higgs
scales of order the Hubble scale during inflation while reducing to far lower
scales in the current era, where they may now be accessible to collider and
other laboratory experiments. In the heavy-lifting option,
renormalization-group running of terrestrial measurements yield predictions for
cosmological non-Gaussianities. If the heavy-lifted gauge theory suffers a
hierarchy problem, such as does the Standard Model, confirming such predictions
would demonstrate a striking violation of the Naturalness Principle. While
observing gauge-Higgs sectors in non-Gaussianities will be challenging given
the constraints of cosmic variance, we show that it may be possible with
reasonable precision given favorable couplings to the inflationary dynamics.
| [
{
"created": "Fri, 10 Nov 2017 19:10:25 GMT",
"version": "v1"
}
] | 2018-05-15 | [
[
"Kumar",
"Soubhik",
""
],
[
"Sundrum",
"Raman",
""
]
] | Future measurements of primordial non-Gaussianity can reveal cosmologically produced particles with masses of order the inflationary Hubble scale and their interactions with the inflaton, giving us crucial insights into the structure of fundamental physics at extremely high energies. We study gauge-Higgs theories that may be accessible in this regime, carefully imposing the constraints of gauge symmetry and its (partial) Higgsing. We distinguish two types of Higgs mechanisms: (i) a standard one in which the Higgs scale is constant before and after inflation, where the particles observable in non-Gaussianities are far heavier than can be accessed by laboratory experiments, perhaps associated with gauge unification, and (ii) a "heavy-lifting" mechanism in which couplings to curvature can result in Higgs scales of order the Hubble scale during inflation while reducing to far lower scales in the current era, where they may now be accessible to collider and other laboratory experiments. In the heavy-lifting option, renormalization-group running of terrestrial measurements yield predictions for cosmological non-Gaussianities. If the heavy-lifted gauge theory suffers a hierarchy problem, such as does the Standard Model, confirming such predictions would demonstrate a striking violation of the Naturalness Principle. While observing gauge-Higgs sectors in non-Gaussianities will be challenging given the constraints of cosmic variance, we show that it may be possible with reasonable precision given favorable couplings to the inflationary dynamics. |
0903.1377 | Mariangela Lisanti | Mariangela Lisanti and Jay G. Wacker | Discovering the Higgs with Low Mass Muon Pairs | 10 pages, 7 figures | Phys.Rev.D79:115006,2009 | 10.1103/PhysRevD.79.115006 | SLAC-PUB-13534 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Many models of electroweak symmetry breaking have an additional light
pseudoscalar. If the Higgs boson can decay to a new pseudoscalar, LEP searches
for the Higgs can be significantly altered and the Higgs can be as light as 86
GeV. Discovering the Higgs boson in these models is challenging when the
pseudoscalar is lighter than 10 GeV because it decays dominantly into tau
leptons. In this paper, we discuss discovering the Higgs in a subdominant decay
mode where one of the pseudoscalars decays to a pair of muons. This search
allows for potential discovery of a cascade-decaying Higgs boson with the
complete Tevatron data set or early data at the LHC.
| [
{
"created": "Sun, 8 Mar 2009 00:09:54 GMT",
"version": "v1"
}
] | 2009-06-30 | [
[
"Lisanti",
"Mariangela",
""
],
[
"Wacker",
"Jay G.",
""
]
] | Many models of electroweak symmetry breaking have an additional light pseudoscalar. If the Higgs boson can decay to a new pseudoscalar, LEP searches for the Higgs can be significantly altered and the Higgs can be as light as 86 GeV. Discovering the Higgs boson in these models is challenging when the pseudoscalar is lighter than 10 GeV because it decays dominantly into tau leptons. In this paper, we discuss discovering the Higgs in a subdominant decay mode where one of the pseudoscalars decays to a pair of muons. This search allows for potential discovery of a cascade-decaying Higgs boson with the complete Tevatron data set or early data at the LHC. |
hep-ph/9909319 | Jan Kalinowski | Wojciech Krolikowski | An alternative for righthanded neutrinos: lefthanded see--saw | LaTeX, 1+6 pages | null | null | IFT/99-21 | hep-ph | null | A new lefthanded see-saw mechanism is constructed, implying both the
smallness of active-neutrino masses and decoupling of heavy passive neutrinos,
similarly to the situation in the case of conventional see-saw. But now, in
place of the conventional righthanded neutrinos, the lefthanded sterile
neutrinos play the role of heavy passive neutrinos, the righthanded neutrinos
and righthanded sterile neutrinos being absent. In this case, the neutrino mass
term is necessarily of pure Majorana type.
| [
{
"created": "Fri, 10 Sep 1999 13:24:37 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Krolikowski",
"Wojciech",
""
]
] | A new lefthanded see-saw mechanism is constructed, implying both the smallness of active-neutrino masses and decoupling of heavy passive neutrinos, similarly to the situation in the case of conventional see-saw. But now, in place of the conventional righthanded neutrinos, the lefthanded sterile neutrinos play the role of heavy passive neutrinos, the righthanded neutrinos and righthanded sterile neutrinos being absent. In this case, the neutrino mass term is necessarily of pure Majorana type. |
1205.0648 | Prashant Shukla | P. K. Khandai, P. Sett, P. Shukla and V. Singh | Transverse mass spectra and scaling of hadrons at RHIC and LHC energies | pages 18, Figures 11 | null | null | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a systematic study of transverse mass spectra ($m_T$) of mesons
and baryons at RHIC and LHC energies. In an earlier study, it was shown that
all the mesons produced in p+p and d+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
follow $m_T$ scaling while in Au+Au collisions at same energy the mesons with
strange and charm quark contents do not follow $m_T$ scaling which can be
attributed to medium modifications.
We extend this study for baryons produced in all above colliding systems at
$\sqrt{s_{NN}}$ = 200 GeV. Although all available baryon spectra behave
differently from mesons but are found to scale with protons for both p+p and
d+Au collisions. In case of Au+Au collisions, the strange baryons behave
differently from protons.
This study has also been performed on the meson spectra in p+p collisions at
62.4 GeV which lies in between the highest RHIC energy and SPS energy where the
$m_T$ scaling was first observed and we arrive at same conclusions as those at
200 GeV.
We test the $m_T$ scaling at LHC with the first meson spectra measured in p+p
collisions at 900 GeV and find that the $m_T$ spectra of kaons and $\phi$ do
not scale with pions. Thus $m_T$ scaling which was working well up to p+p
collisions at 200 GeV seems to be broken. Here we use all data measured in the
mid rapidity region. Baryon to meson ratio is studied as a function of $m_T$,
at different energies and for different systems and is found that this ratio
for p+p at 900 GeV is quite different from that in p+p collisions at RHIC
energies.
| [
{
"created": "Thu, 3 May 2012 08:32:48 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jun 2012 12:56:38 GMT",
"version": "v2"
}
] | 2012-07-02 | [
[
"Khandai",
"P. K.",
""
],
[
"Sett",
"P.",
""
],
[
"Shukla",
"P.",
""
],
[
"Singh",
"V.",
""
]
] | We present a systematic study of transverse mass spectra ($m_T$) of mesons and baryons at RHIC and LHC energies. In an earlier study, it was shown that all the mesons produced in p+p and d+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV follow $m_T$ scaling while in Au+Au collisions at same energy the mesons with strange and charm quark contents do not follow $m_T$ scaling which can be attributed to medium modifications. We extend this study for baryons produced in all above colliding systems at $\sqrt{s_{NN}}$ = 200 GeV. Although all available baryon spectra behave differently from mesons but are found to scale with protons for both p+p and d+Au collisions. In case of Au+Au collisions, the strange baryons behave differently from protons. This study has also been performed on the meson spectra in p+p collisions at 62.4 GeV which lies in between the highest RHIC energy and SPS energy where the $m_T$ scaling was first observed and we arrive at same conclusions as those at 200 GeV. We test the $m_T$ scaling at LHC with the first meson spectra measured in p+p collisions at 900 GeV and find that the $m_T$ spectra of kaons and $\phi$ do not scale with pions. Thus $m_T$ scaling which was working well up to p+p collisions at 200 GeV seems to be broken. Here we use all data measured in the mid rapidity region. Baryon to meson ratio is studied as a function of $m_T$, at different energies and for different systems and is found that this ratio for p+p at 900 GeV is quite different from that in p+p collisions at RHIC energies. |
hep-ph/0210304 | Brian C. Tiburzi | B. C. Tiburzi, G. A. Miller | Current in the light-front Bethe-Salpeter formalism I: Replacement of
non-wave function vertices | 11 pages, 10 figures, 1 Table, RevTex4 | Phys.Rev. D67 (2003) 054014 | 10.1103/PhysRevD.67.054014 | NT-UW 02-30 | hep-ph nucl-th | null | We apply the light-front reduction of the Bethe-Salpeter equation to matrix
elements of the electromagnetic current between bound states. Using a simple
(1+1)-dimensional model to calculate form factors, we focus on two cases. In
one case, the interaction is dominated by a term instantaneous in light-cone
time. Here effects of higher Fock states are negligible and the form factor can
be effectively expressed using non-wave function vertices and crossed
interactions. If the interaction is not instantaneous, non-wave function
vertices are replaced by contributions from higher Fock states. These higher
Fock components arise from the covariant formalism via the energy poles of the
Bethe-Salpeter vertex and the electromagnetic vertex. The replacement of
non-wave function vertices in time-ordered perturbation theory is a theorem
which directly extends to generalized parton distributions, e.g., in (3+1)
dimensions.
| [
{
"created": "Wed, 23 Oct 2002 03:01:29 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Tiburzi",
"B. C.",
""
],
[
"Miller",
"G. A.",
""
]
] | We apply the light-front reduction of the Bethe-Salpeter equation to matrix elements of the electromagnetic current between bound states. Using a simple (1+1)-dimensional model to calculate form factors, we focus on two cases. In one case, the interaction is dominated by a term instantaneous in light-cone time. Here effects of higher Fock states are negligible and the form factor can be effectively expressed using non-wave function vertices and crossed interactions. If the interaction is not instantaneous, non-wave function vertices are replaced by contributions from higher Fock states. These higher Fock components arise from the covariant formalism via the energy poles of the Bethe-Salpeter vertex and the electromagnetic vertex. The replacement of non-wave function vertices in time-ordered perturbation theory is a theorem which directly extends to generalized parton distributions, e.g., in (3+1) dimensions. |
2111.01463 | Xin-Qiang Li | Li-Fen Lai, Xin-Qiang Li, Xin-Shuai Yan, and Ya-Dong Yang | Prospects for discovering new physics in charm sector through low-energy
scattering processes $e^-p\to e^- (\mu^-)\Lambda_c$ | 18 pages, 4 figures, and 6 tables; details of the amplitudes squared
and further discussions added, final version to be published in PRD | null | 10.1103/PhysRevD.105.035007 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the potential for discovering new physics through the
low-energy scattering processes $e^-p\to e^-(\mu^-)\Lambda_c$, which could be
accessible in the forthcoming $ep$ scattering experiments once adapted to our
proposed setups. In the framework of a general low-energy effective Lagrangian,
we demonstrate that, compared with the conventional flavor-changing
neutral-current weak decays of charmed hadrons and the dilepton productions at
high-energy colliders, the low-energy scattering processes can provide more
competitive potentials for hunting the underlying new physics. In some specific
leptoquark models, we also show that promising event rates can be expected for
both the scattering processes, and point out a possible way to distinguish the
experimental signals due to the scalar leptoquarks from those of the vector
ones.
| [
{
"created": "Tue, 2 Nov 2021 10:01:48 GMT",
"version": "v1"
},
{
"created": "Thu, 3 Feb 2022 11:20:23 GMT",
"version": "v2"
}
] | 2022-02-23 | [
[
"Lai",
"Li-Fen",
""
],
[
"Li",
"Xin-Qiang",
""
],
[
"Yan",
"Xin-Shuai",
""
],
[
"Yang",
"Ya-Dong",
""
]
] | We investigate the potential for discovering new physics through the low-energy scattering processes $e^-p\to e^-(\mu^-)\Lambda_c$, which could be accessible in the forthcoming $ep$ scattering experiments once adapted to our proposed setups. In the framework of a general low-energy effective Lagrangian, we demonstrate that, compared with the conventional flavor-changing neutral-current weak decays of charmed hadrons and the dilepton productions at high-energy colliders, the low-energy scattering processes can provide more competitive potentials for hunting the underlying new physics. In some specific leptoquark models, we also show that promising event rates can be expected for both the scattering processes, and point out a possible way to distinguish the experimental signals due to the scalar leptoquarks from those of the vector ones. |
2404.19037 | Lisa Biermann | Philipp Basler, Lisa Biermann, Margarete M\"uhlleitner, Jonas
M\"uller, Rui Santos, Jo\~ao Viana | BSMPT v3 A Tool for Phase Transitions and Primordial Gravitational Waves
in Extended Higgs Sectors | 78 pages, 13 figures, 4 tables | null | null | KA-TP-08-2024 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Strong first-order phase transitions (SFOPT) during the evolution of the
Higgs potential in the early universe not only allow for the dynamical
generation of the observed matter-antimatter asymmetry, they can also source a
stochastic gravitational wave (GW) background possibly detectable with future
space-based gravitational waves interferometers. As SFOPTs are
phenomenologically incompatible with the Standard Model (SM) Higgs sector, the
observation of GWs from SFOPTs provides an exciting interplay between cosmology
and particle physics in the search for new physics. With the C++ code BSMPTv3,
we present for the first time a tool that performs the whole chain from the
particle physics model to the gravitational wave spectrum. Extending the
previous versions BSMPTv1 and v2, it traces the phases of beyond-SM (BSM) Higgs
potentials and is capable of treating multiple vacuum directions and multi-step
phase transitions. During the tracing, it checks for discrete symmetries, flat
directions, and electroweak symmetry restoration, and finally reports the
transition history. The transition probability from the false to the true
vacuum is obtained from the solution of the bounce equation which allows for
the calculation of the nucleation, percolation and completion temperatures. The
peak amplitude and frequency of the GWs originating from sound waves and
turbulence, are evaluated after the calculation of the thermal parameters at
the transition temperature, and finally the signal-to-noise ratio at LISA is
provided. The code BSMPTv3 is a powerful self-contained tool that comes more
than timely and will be of great benefit for investigations of the vacuum
structure of the early universe of not only simple but also complicated Higgs
potentials involving several vacuum directions, with exciting applications in
the search for new physics.
| [
{
"created": "Mon, 29 Apr 2024 18:24:41 GMT",
"version": "v1"
}
] | 2024-05-01 | [
[
"Basler",
"Philipp",
""
],
[
"Biermann",
"Lisa",
""
],
[
"Mühlleitner",
"Margarete",
""
],
[
"Müller",
"Jonas",
""
],
[
"Santos",
"Rui",
""
],
[
"Viana",
"João",
""
]
] | Strong first-order phase transitions (SFOPT) during the evolution of the Higgs potential in the early universe not only allow for the dynamical generation of the observed matter-antimatter asymmetry, they can also source a stochastic gravitational wave (GW) background possibly detectable with future space-based gravitational waves interferometers. As SFOPTs are phenomenologically incompatible with the Standard Model (SM) Higgs sector, the observation of GWs from SFOPTs provides an exciting interplay between cosmology and particle physics in the search for new physics. With the C++ code BSMPTv3, we present for the first time a tool that performs the whole chain from the particle physics model to the gravitational wave spectrum. Extending the previous versions BSMPTv1 and v2, it traces the phases of beyond-SM (BSM) Higgs potentials and is capable of treating multiple vacuum directions and multi-step phase transitions. During the tracing, it checks for discrete symmetries, flat directions, and electroweak symmetry restoration, and finally reports the transition history. The transition probability from the false to the true vacuum is obtained from the solution of the bounce equation which allows for the calculation of the nucleation, percolation and completion temperatures. The peak amplitude and frequency of the GWs originating from sound waves and turbulence, are evaluated after the calculation of the thermal parameters at the transition temperature, and finally the signal-to-noise ratio at LISA is provided. The code BSMPTv3 is a powerful self-contained tool that comes more than timely and will be of great benefit for investigations of the vacuum structure of the early universe of not only simple but also complicated Higgs potentials involving several vacuum directions, with exciting applications in the search for new physics. |
1911.05527 | Christoph Englert | Christoph Englert, David J. Miller, Dumitru Dan Smaranda | Phenomenology of GUT-inspired gauge-Higgs unification | 10 pages, 9 figures, 1 table; v2: references added, version published
in PLB | null | 10.1016/j.physletb.2020.135261 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a detailed investigation of a Grand Unified Theory (GUT)-inspired
theory of gauge-Higgs unification. Scanning the model's parameter space with
adapted numerical techniques, we contrast the scenario's low energy limit with
existing SM and collider search constraints. We discuss potential modifications
of di-Higgs phenomenology at hadron colliders as sensitive probes of the
gauge-like character of the Higgs self-interactions and find that for
phenomenologically viable parameter choices modifications of the order of 20\%
compared to the SM cross section can be expected. While these modifications are
challenging to observe at the LHC, a future 100 TeV hadron collider might be
able to constrain the scenario through more precise di-Higgs measurements. We
point out alternative signatures that can be employed to constrain this model
in the near future.
| [
{
"created": "Wed, 13 Nov 2019 15:04:14 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Feb 2020 11:12:36 GMT",
"version": "v2"
}
] | 2020-02-05 | [
[
"Englert",
"Christoph",
""
],
[
"Miller",
"David J.",
""
],
[
"Smaranda",
"Dumitru Dan",
""
]
] | We perform a detailed investigation of a Grand Unified Theory (GUT)-inspired theory of gauge-Higgs unification. Scanning the model's parameter space with adapted numerical techniques, we contrast the scenario's low energy limit with existing SM and collider search constraints. We discuss potential modifications of di-Higgs phenomenology at hadron colliders as sensitive probes of the gauge-like character of the Higgs self-interactions and find that for phenomenologically viable parameter choices modifications of the order of 20\% compared to the SM cross section can be expected. While these modifications are challenging to observe at the LHC, a future 100 TeV hadron collider might be able to constrain the scenario through more precise di-Higgs measurements. We point out alternative signatures that can be employed to constrain this model in the near future. |
2310.18829 | Boris Kopeliovich | Boris Kopeliovich, Irina Potashnikova, Ivan Schmidt | Abundant radiation of soft photons: a puzzle lasting four decades | 8 pages 8 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The observed enhancement of low-kT photons in comparison with incorrect
calculations, should not be treated as a puzzle. The paper by Low considered a
large rapidity gap process of diffractive excitation of a hadron, h ->
h+\gamma, rather than multiple hadron production spanning all over the rapidity
interval between colliding hadrons. The optical theorem connects these two
processes, and what is inner bremsstrahlung, suppressed according to Low,
corresponds to radiation from final state hadrons. Thus, the main result of the
Low theorem, based on gauge invariance of the diffractive bremsstrahlung
amplitude, supplemented with the optical theorem, contradicts the so-called
bremsstrahlung model. The latter has been used for comparison with data,
leading to the longstanding soft photon puzzle.
| [
{
"created": "Sat, 28 Oct 2023 21:58:21 GMT",
"version": "v1"
}
] | 2023-10-31 | [
[
"Kopeliovich",
"Boris",
""
],
[
"Potashnikova",
"Irina",
""
],
[
"Schmidt",
"Ivan",
""
]
] | The observed enhancement of low-kT photons in comparison with incorrect calculations, should not be treated as a puzzle. The paper by Low considered a large rapidity gap process of diffractive excitation of a hadron, h -> h+\gamma, rather than multiple hadron production spanning all over the rapidity interval between colliding hadrons. The optical theorem connects these two processes, and what is inner bremsstrahlung, suppressed according to Low, corresponds to radiation from final state hadrons. Thus, the main result of the Low theorem, based on gauge invariance of the diffractive bremsstrahlung amplitude, supplemented with the optical theorem, contradicts the so-called bremsstrahlung model. The latter has been used for comparison with data, leading to the longstanding soft photon puzzle. |
hep-ph/0205314 | Hsin-Chia Cheng | Hsin-Chia Cheng, Konstantin T. Matchev, Martin Schmaltz | Bosonic Supersymmetry? Getting Fooled at the LHC | 6 pages, 4 figures, RevTeX4 | Phys.Rev.D66:056006,2002 | 10.1103/PhysRevD.66.056006 | EFI-02-80, UFIFT-HEP-02-7, CERN-TH/2002-108, BUHEP-02-21 | hep-ph hep-ex | null | We define a minimal model with Universal Extra Dimensions, and begin to study
its phenomenology. The collider signals of the first KK level are surprisingly
similar to those of a supersymmetric model with a nearly degenerate
superpartner spectrum. The lightest KK particle (LKP) is neutral and stable
because of KK-parity. KK excitations cascade decay to the LKP yielding missing
energy signatures with relatively soft jets and leptons. Level 2 KK modes may
also be probed via their KK number violating decays to Standard Model
particles. In either case we provide initial estimates for the discovery
potential of the Tevatron and the LHC.
| [
{
"created": "Tue, 28 May 2002 19:35:37 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Cheng",
"Hsin-Chia",
""
],
[
"Matchev",
"Konstantin T.",
""
],
[
"Schmaltz",
"Martin",
""
]
] | We define a minimal model with Universal Extra Dimensions, and begin to study its phenomenology. The collider signals of the first KK level are surprisingly similar to those of a supersymmetric model with a nearly degenerate superpartner spectrum. The lightest KK particle (LKP) is neutral and stable because of KK-parity. KK excitations cascade decay to the LKP yielding missing energy signatures with relatively soft jets and leptons. Level 2 KK modes may also be probed via their KK number violating decays to Standard Model particles. In either case we provide initial estimates for the discovery potential of the Tevatron and the LHC. |
2012.05555 | Mariana Panayotova | Daniela Kirilova, Mariana Panayotova | Scalar Field Condensate Baryogenesis Model in Different Inflationary
Scenarios | 8 pages, 1 figure | null | null | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the baryon asymmetry value generated in the Scalar Field
Condensate (SCF) baryogenesis model obtained in several inflationary scenarios
and different reheating models. We provide analysis of the baryon asymmetry
value obtained for more than 70 sets of parameters of the SCF model and the
following inflationary scenarios, namely: new inflation, chaotic inflation,
Starobinsky inflation, MSSM inflation, quintessential inflation. We considered
both cases of efficient thermalization after inflation and also delayed
thermalization. We have found that SFC baryogenesis model produces baryon
asymmetry by orders of magnitude bigger than the observed one for the following
inflationary models: new inflation, new inflation model by Shafi and Vilenkin,
MSSM inflation, chaotic inflation with high reheating temperature and the
simplest Shafi-Vilenkin chaotic inflationary model. For these models strong
diluting mechanisms are needed to reduce the resultant baryon excess at low
energies to its observational value today. We have found that a successful
generation of the observed baryon asymmetry is possible by SCF baryogenesis
model in Modified Starobinsky inflation, chaotic inflation with low reheating
temperature, chaotic inflation in SUGRA and Quintessential inflation.
| [
{
"created": "Thu, 10 Dec 2020 09:57:12 GMT",
"version": "v1"
}
] | 2021-01-19 | [
[
"Kirilova",
"Daniela",
""
],
[
"Panayotova",
"Mariana",
""
]
] | We calculate the baryon asymmetry value generated in the Scalar Field Condensate (SCF) baryogenesis model obtained in several inflationary scenarios and different reheating models. We provide analysis of the baryon asymmetry value obtained for more than 70 sets of parameters of the SCF model and the following inflationary scenarios, namely: new inflation, chaotic inflation, Starobinsky inflation, MSSM inflation, quintessential inflation. We considered both cases of efficient thermalization after inflation and also delayed thermalization. We have found that SFC baryogenesis model produces baryon asymmetry by orders of magnitude bigger than the observed one for the following inflationary models: new inflation, new inflation model by Shafi and Vilenkin, MSSM inflation, chaotic inflation with high reheating temperature and the simplest Shafi-Vilenkin chaotic inflationary model. For these models strong diluting mechanisms are needed to reduce the resultant baryon excess at low energies to its observational value today. We have found that a successful generation of the observed baryon asymmetry is possible by SCF baryogenesis model in Modified Starobinsky inflation, chaotic inflation with low reheating temperature, chaotic inflation in SUGRA and Quintessential inflation. |
0807.5039 | Jernej Kamenik | Tobias Hurth, Gino Isidori, Jernej F. Kamenik, Federico Mescia | Constraints on New Physics in MFV models: a model-independent analysis
of Delta F=1 processes | 23 pages, 7 figures (v2: very minor modifications - published
version) | Nucl.Phys.B808:326-346,2009 | 10.1016/j.nuclphysb.2008.09.040 | CERN-PH-TH/2008-161, SLAC-PUB-13342 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyse the constraints on dimension-six Delta F=1 effective operators in
models respecting the MFV hypothesis, both in the one-Higgs doublet case and in
the two-Higgs doublet scenario with large tan beta. The constraints are derived
mainly from the b -> s inclusive observables measured at the B factories. The
implications of these bounds in view of improved measurements in exclusive and
inclusive observables in b -> s l^+ l^- and s -> d nu nubar transitions are
discussed.
| [
{
"created": "Thu, 31 Jul 2008 12:03:44 GMT",
"version": "v1"
},
{
"created": "Sat, 13 Dec 2008 16:41:19 GMT",
"version": "v2"
}
] | 2008-12-18 | [
[
"Hurth",
"Tobias",
""
],
[
"Isidori",
"Gino",
""
],
[
"Kamenik",
"Jernej F.",
""
],
[
"Mescia",
"Federico",
""
]
] | We analyse the constraints on dimension-six Delta F=1 effective operators in models respecting the MFV hypothesis, both in the one-Higgs doublet case and in the two-Higgs doublet scenario with large tan beta. The constraints are derived mainly from the b -> s inclusive observables measured at the B factories. The implications of these bounds in view of improved measurements in exclusive and inclusive observables in b -> s l^+ l^- and s -> d nu nubar transitions are discussed. |
1705.00343 | Maria Ubiali Dr | Radja Boughezal, Alberto Guffanti, Frank Petriello, Maria Ubiali | The impact of the LHC Z-boson transverse momentum data on PDF
determinations | 36 pages, 18 figures | null | 10.1007/JHEP07(2017)130 | CAVENDISH-HEP-17/05 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The LHC has recently released precise measurements of the transverse momentum
distribution of the Z-boson that provide a unique constraint on the structure
of the proton. Theoretical developments now allow the prediction of these
observables through next-to-next-to-leading order (NNLO) in perturbative QCD.
In this work we study the impact of incorporating these latest advances into a
determination of parton distribution functions (PDFs) through NNLO including
the recent ATLAS and CMS 7 TeV and 8 TeV $p_T^Z$ data. We investigate the
consistency of these measurements in a global fit to the available data and
quantify the impact of including the $p_T^Z$ distributions on the PDFs. The
inclusion of these new data sets significantly reduces the uncertainties on
select parton distributions and the corresponding parton-parton luminosities.
In particular, we find that the $p_T^Z$ data ultimately leads to a reduction of
the PDF uncertainty on the gluon-fusion and vector-boson fusion Higgs
production cross sections by about 30%, while keeping the central values nearly
unchanged.
| [
{
"created": "Sun, 30 Apr 2017 16:59:18 GMT",
"version": "v1"
},
{
"created": "Tue, 9 May 2017 09:53:19 GMT",
"version": "v2"
}
] | 2017-09-13 | [
[
"Boughezal",
"Radja",
""
],
[
"Guffanti",
"Alberto",
""
],
[
"Petriello",
"Frank",
""
],
[
"Ubiali",
"Maria",
""
]
] | The LHC has recently released precise measurements of the transverse momentum distribution of the Z-boson that provide a unique constraint on the structure of the proton. Theoretical developments now allow the prediction of these observables through next-to-next-to-leading order (NNLO) in perturbative QCD. In this work we study the impact of incorporating these latest advances into a determination of parton distribution functions (PDFs) through NNLO including the recent ATLAS and CMS 7 TeV and 8 TeV $p_T^Z$ data. We investigate the consistency of these measurements in a global fit to the available data and quantify the impact of including the $p_T^Z$ distributions on the PDFs. The inclusion of these new data sets significantly reduces the uncertainties on select parton distributions and the corresponding parton-parton luminosities. In particular, we find that the $p_T^Z$ data ultimately leads to a reduction of the PDF uncertainty on the gluon-fusion and vector-boson fusion Higgs production cross sections by about 30%, while keeping the central values nearly unchanged. |
1211.4003 | Simon Dalley | Simon Dalley, Santosh Adhikari, Pavel Nadolsky | Optimizing Polar Angle Asymmetry Observables at Colliders | 6 pages, 2 figures, presented at Light Cone 2012, Cracow, Poland,
8-13 July | null | null | SMU-HEP-12-22 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Angular asymmetries are simple, intuitive, model-independent observables used
to identify spins of new elementary particles. In the case of Drell-Yan-like
boson resonances, we generalize the well-known center-edge angular asymmetry to
optimize spin identification when only a limited sample of events is available.
By choosing simple weight functions in integrals over the polar angle theta,
such as cos theta to the nth power, we can improve spin discrimination
significantly in production and decays of spin 0, 1, and 2 bosons. The power n
can be tuned in particular cases, but n=2 (n=1) works well for any
forward-backward symmetric (non-symmetric) decay to massless particles.
| [
{
"created": "Fri, 16 Nov 2012 19:59:02 GMT",
"version": "v1"
}
] | 2012-11-19 | [
[
"Dalley",
"Simon",
""
],
[
"Adhikari",
"Santosh",
""
],
[
"Nadolsky",
"Pavel",
""
]
] | Angular asymmetries are simple, intuitive, model-independent observables used to identify spins of new elementary particles. In the case of Drell-Yan-like boson resonances, we generalize the well-known center-edge angular asymmetry to optimize spin identification when only a limited sample of events is available. By choosing simple weight functions in integrals over the polar angle theta, such as cos theta to the nth power, we can improve spin discrimination significantly in production and decays of spin 0, 1, and 2 bosons. The power n can be tuned in particular cases, but n=2 (n=1) works well for any forward-backward symmetric (non-symmetric) decay to massless particles. |
2007.04191 | Qin Qin | Tobias Huber, Tobias Hurth, Jack Jenkins, Enrico Lunghi, Qin Qin,
K.Keri Vos | Phenomenology of inclusive $\bar{B}\to X_s \ell^+ \ell^-$ for the Belle
II era | match the published version | JHEP10(2020)088 | 10.1007/JHEP10(2020)088 | SI-HEP-2020-13 , P3H-20-030, MITP/20-37, TUM/1268-20 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | With the first data being recorded at Belle II, we are at the brink of a new
era in quark flavour physics. The many exciting new opportunities for Belle~II
include a full angular analysis of inclusive ${\bar B \to X_{s} \,
\ell^+\ell^-}$ which has the potential to reveal new physics, in particular by
its interplay with the exclusive $b \to s \ell^+\ell^-$ counterparts studied
extensively at LHCb. In this paper, we present fully updated Standard Model
predictions for all angular observables necessary for this endeavour. These
predictions are tailored to Belle II and include an elaborate study of the
treatment of collinear photons which become crucial when aiming for the highest
precision. In addition, we present a phenomenological study of the potential
for Belle II to reveal possible new physics in the inclusive decay channel,
both in an independent manner and in combination with exclusive modes.
| [
{
"created": "Wed, 8 Jul 2020 15:30:43 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Oct 2020 03:26:50 GMT",
"version": "v2"
}
] | 2020-10-20 | [
[
"Huber",
"Tobias",
""
],
[
"Hurth",
"Tobias",
""
],
[
"Jenkins",
"Jack",
""
],
[
"Lunghi",
"Enrico",
""
],
[
"Qin",
"Qin",
""
],
[
"Vos",
"K. Keri",
""
]
] | With the first data being recorded at Belle II, we are at the brink of a new era in quark flavour physics. The many exciting new opportunities for Belle~II include a full angular analysis of inclusive ${\bar B \to X_{s} \, \ell^+\ell^-}$ which has the potential to reveal new physics, in particular by its interplay with the exclusive $b \to s \ell^+\ell^-$ counterparts studied extensively at LHCb. In this paper, we present fully updated Standard Model predictions for all angular observables necessary for this endeavour. These predictions are tailored to Belle II and include an elaborate study of the treatment of collinear photons which become crucial when aiming for the highest precision. In addition, we present a phenomenological study of the potential for Belle II to reveal possible new physics in the inclusive decay channel, both in an independent manner and in combination with exclusive modes. |
1911.09746 | Pedro Miguel Martins Ferreira | P.M. Ferreira, B.L. Gon\c{c}alves | Stability of neutral minima against charge breaking in the Higgs triplet
model | Appendix C added, minor changes requested by referee | null | 10.1007/JHEP02(2020)182 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyse the possibility of charge breaking minima developing in the Higgs
triplet model, and under what conditions they are deeper than charge-preserving
ones. Analytical expressions relating the depth of minima of different types
are deduced. A global symmetry of the model leads to increased stability for
charge-preserving vacua. However, if that symmetry is broken by a soft term,
deeper charge-breaking minima may occur more easily. We identify the vev
configurations most likely to produce charge breaking minima.
| [
{
"created": "Thu, 21 Nov 2019 21:03:40 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Dec 2019 17:55:36 GMT",
"version": "v2"
},
{
"created": "Fri, 31 Jan 2020 12:21:14 GMT",
"version": "v3"
}
] | 2020-03-18 | [
[
"Ferreira",
"P. M.",
""
],
[
"Gonçalves",
"B. L.",
""
]
] | We analyse the possibility of charge breaking minima developing in the Higgs triplet model, and under what conditions they are deeper than charge-preserving ones. Analytical expressions relating the depth of minima of different types are deduced. A global symmetry of the model leads to increased stability for charge-preserving vacua. However, if that symmetry is broken by a soft term, deeper charge-breaking minima may occur more easily. We identify the vev configurations most likely to produce charge breaking minima. |
1804.07409 | Fred Jegerlehner | Fred Jegerlehner | The Muon g-2 in Progress | 19 pages, 23 figures. Note added on impact of new alpha from atomic
interferometry on prediction of the electron g-2. Two references added
[74],[75] | null | 10.5506/APhysPolB.49.1157 | DESY~18-057, HU-EP-18/11 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Two next generation muon $g-2$ experiments at Fermilab in the US and at
J-PARC in Japan have been designed to reach a four times better precision from
0.54 ppm to 0.14 ppm and the challenge for the theory side is to keep up in
precision as far as possible. This has triggered a lot of new research
activities. The main motivation is the persisting 3 to 4 $\sigma$ deviation
between standard theory and experiment. As Standard Model predictions almost
without exception match perfectly all other experimental information, the
deviation in one of the most precisely measured quantities in particle physics
remains a mystery and inspires the imagination of model builders. Plenty of
speculations are aiming to explain what beyond the Standard Model effects could
fill what seems to be missing. Here very high precision experiments are
competing with searches for new physics at the high energy frontier lead by the
Large Hadron Collider at CERN. Actually, the tension is increasing steadily as
no new states are found which could accommodate the $g_\mu-2$ discrepancy. With
the new muon $g-2$ experiments this discrepancy would go up at least to 6
$\sigma$, in case the central values do not move, up to 10 $\sigma$ could be
reached if the present theory error could be reduced by a factor of two.
Interestingly, the new $\alpha$ from Berkeley by R. H. Parker et al. Science
360, 191 (2018): $\alpha^{-1}({\rm Cs18})=137.035999046(27)$ gives an $a_e$
prediction $a_e=0.00115965218157(23)$ such that $a_e^{\rm exp}-a_e^{\rm
the}=(-84\pm36)\times 10^{-14}$ shows a $- 2.3~ \sigma$ deviation now.
| [
{
"created": "Fri, 20 Apr 2018 00:11:20 GMT",
"version": "v1"
},
{
"created": "Sat, 28 Apr 2018 23:24:29 GMT",
"version": "v2"
}
] | 2018-08-01 | [
[
"Jegerlehner",
"Fred",
""
]
] | Two next generation muon $g-2$ experiments at Fermilab in the US and at J-PARC in Japan have been designed to reach a four times better precision from 0.54 ppm to 0.14 ppm and the challenge for the theory side is to keep up in precision as far as possible. This has triggered a lot of new research activities. The main motivation is the persisting 3 to 4 $\sigma$ deviation between standard theory and experiment. As Standard Model predictions almost without exception match perfectly all other experimental information, the deviation in one of the most precisely measured quantities in particle physics remains a mystery and inspires the imagination of model builders. Plenty of speculations are aiming to explain what beyond the Standard Model effects could fill what seems to be missing. Here very high precision experiments are competing with searches for new physics at the high energy frontier lead by the Large Hadron Collider at CERN. Actually, the tension is increasing steadily as no new states are found which could accommodate the $g_\mu-2$ discrepancy. With the new muon $g-2$ experiments this discrepancy would go up at least to 6 $\sigma$, in case the central values do not move, up to 10 $\sigma$ could be reached if the present theory error could be reduced by a factor of two. Interestingly, the new $\alpha$ from Berkeley by R. H. Parker et al. Science 360, 191 (2018): $\alpha^{-1}({\rm Cs18})=137.035999046(27)$ gives an $a_e$ prediction $a_e=0.00115965218157(23)$ such that $a_e^{\rm exp}-a_e^{\rm the}=(-84\pm36)\times 10^{-14}$ shows a $- 2.3~ \sigma$ deviation now. |
2004.11919 | Xun-Jie Xu | Frank F. Deppisch, Lukas Graf, Werner Rodejohann, Xun-Jie Xu | Neutrino Self-Interactions and Double Beta Decay | 10 pages, 5 figures | Phys. Rev. D 102, 051701 (2020) | 10.1103/PhysRevD.102.051701 | null | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Neutrino Self-Interactions ($\nu$SI) beyond the Standard Model are an
attractive possibility to soften cosmological constraints on neutrino
properties and also to explain the tension in late and early time measurements
of the Hubble expansion rate. The required strength of $\nu$SI to explain the
$4\sigma$ Hubble tension is in terms of a point-like effective four-fermion
coupling that can be as high as $10^9\, G_F$, where $G_F$ is the Fermi
constant. In this work, we show that such strong $\nu$SI can cause significant
effects in two-neutrino double beta decay, leading to an observable enhancement
of decay rates and to spectrum distortions. We analyze self-interactions via an
effective operator as well as when mediated by a light scalar. Data from
observed two-neutrino double beta decay is used to constrain $\nu$SI, which
rules out the regime around $10^9\, G_F$.
| [
{
"created": "Fri, 24 Apr 2020 18:02:28 GMT",
"version": "v1"
}
] | 2020-09-09 | [
[
"Deppisch",
"Frank F.",
""
],
[
"Graf",
"Lukas",
""
],
[
"Rodejohann",
"Werner",
""
],
[
"Xu",
"Xun-Jie",
""
]
] | Neutrino Self-Interactions ($\nu$SI) beyond the Standard Model are an attractive possibility to soften cosmological constraints on neutrino properties and also to explain the tension in late and early time measurements of the Hubble expansion rate. The required strength of $\nu$SI to explain the $4\sigma$ Hubble tension is in terms of a point-like effective four-fermion coupling that can be as high as $10^9\, G_F$, where $G_F$ is the Fermi constant. In this work, we show that such strong $\nu$SI can cause significant effects in two-neutrino double beta decay, leading to an observable enhancement of decay rates and to spectrum distortions. We analyze self-interactions via an effective operator as well as when mediated by a light scalar. Data from observed two-neutrino double beta decay is used to constrain $\nu$SI, which rules out the regime around $10^9\, G_F$. |
1206.2892 | Sanjay Padhi | Michael Kr\"amer, Anna Kulesza, Robin van der Leeuw, Michelangelo
Mangano, Sanjay Padhi, Tilman Plehn and Xavier Portell | Supersymmetry production cross sections in pp collisions at sqrt{s} = 7
TeV | null | null | null | CERN-PH-TH/2012-163 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This document emerged from work that started in January 2012 as a joint
effort by the ATLAS, CMS and LPCC supersymmetry (SUSY) working groups to
compile state-of-the-art cross section predictions for SUSY particle production
at the LHC. We present cross sections for various SUSY processes in pp
collisions at $\sqrt{s} =7$ TeV, including an estimate of the theoretical
uncertainty due to scale variation and the parton distribution functions.
Further results for higher LHC centre-of-mass energies will be collected at
https://twiki.cern.ch/twiki/bin/view/LHCPhysics/SUSYCrossSections. For squark
and gluino production, which dominate the inclusive SUSY cross section, we
employ calculations which include the resummation of soft gluon emission at
next-to-leading logarithmic accuracy, matched to next-to-leading order (NLO)
SUSY-QCD. In all other cases we rely on NLO SUSY-QCD predictions.
| [
{
"created": "Wed, 13 Jun 2012 18:39:00 GMT",
"version": "v1"
}
] | 2012-06-14 | [
[
"Krämer",
"Michael",
""
],
[
"Kulesza",
"Anna",
""
],
[
"van der Leeuw",
"Robin",
""
],
[
"Mangano",
"Michelangelo",
""
],
[
"Padhi",
"Sanjay",
""
],
[
"Plehn",
"Tilman",
""
],
[
"Portell",
"Xavier",
""
]
] | This document emerged from work that started in January 2012 as a joint effort by the ATLAS, CMS and LPCC supersymmetry (SUSY) working groups to compile state-of-the-art cross section predictions for SUSY particle production at the LHC. We present cross sections for various SUSY processes in pp collisions at $\sqrt{s} =7$ TeV, including an estimate of the theoretical uncertainty due to scale variation and the parton distribution functions. Further results for higher LHC centre-of-mass energies will be collected at https://twiki.cern.ch/twiki/bin/view/LHCPhysics/SUSYCrossSections. For squark and gluino production, which dominate the inclusive SUSY cross section, we employ calculations which include the resummation of soft gluon emission at next-to-leading logarithmic accuracy, matched to next-to-leading order (NLO) SUSY-QCD. In all other cases we rely on NLO SUSY-QCD predictions. |
hep-ph/0312130 | Ralf Hofmann | Ralf Hofmann | Operator Product Expansion and Quark-Hadron Duality: Facts and Riddles | now 68 pages, 29 figures (1 figure added), habilitation thesis, mild
restructuring, typos corrected, about 30 references and corresponding text
added, version to be published in Prog. Part. Nucl. Phys | Prog.Part.Nucl.Phys. 52 (2004) 299-376 | 10.1016/j.ppnp.2004.02.003 | null | hep-ph | null | We review the status of the practical operator product expansion (OPE), when
applied to two-point correlators of QCD currents which interpolate to mesonic
resonances, in view of the violations of local quark-hadron duality. Covered
topics are: a mini-review of mesonic QCD sum rules in vacuum, at finite
temperature, or at finite baryon density, a comparison of model calculations of
current-current correlation functions in 2D and 4D with the OPE expression, a
discussion of meson distribution amplitudes in the light of nonperturbatively
nonlocal modifications of the OPE, and a reorganization of the OPE which
(partially) resums powers of covariant derivatives.
| [
{
"created": "Tue, 9 Dec 2003 19:14:52 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Jan 2004 10:11:21 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Hofmann",
"Ralf",
""
]
] | We review the status of the practical operator product expansion (OPE), when applied to two-point correlators of QCD currents which interpolate to mesonic resonances, in view of the violations of local quark-hadron duality. Covered topics are: a mini-review of mesonic QCD sum rules in vacuum, at finite temperature, or at finite baryon density, a comparison of model calculations of current-current correlation functions in 2D and 4D with the OPE expression, a discussion of meson distribution amplitudes in the light of nonperturbatively nonlocal modifications of the OPE, and a reorganization of the OPE which (partially) resums powers of covariant derivatives. |
2302.04639 | Lei Wang | Songtao Liu, Lei Wang | Spontaneous CP violation electroweak baryogenesis and gravitational wave
through multi-step phase transitions | 21 pages, 5 figures, 1 Table | null | null | null | hep-ph astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | In a singlet pseudoscalar extension of the two-Higgs-doublet model we discuss
spontaneous CP violation electroweak baryogenesis via two different patterns of
phase transitions (PTs): (i) two-step PTs whose first-step and second-step are
strongly first-order; (ii) three-step PTs whose first-step is second-order and
the second-step and third-step are strongly first-order. For the case of the
two-step pattern, the first-step PT takes place at a high temperature,
converting the origin phase into an electroweak symmetry broken phase and
breaking the CP symmetry spontaneously. Thus, the baryon number is produced
during the first-step PT. At the second-step PT, the phase is converted into
the observed vacuum at zero temperature, and the CP-symmetry is restored. In
both phases the sphaleron processes are sufficiently suppressed, which keep the
baryon number unchanged. For the case of the three-step PTs, the pseudoscalar
field firstly acquires a nonzero VEV, and VEVs of other fields still remain
zero during the first-step PT. The following PTs and electroweak baryogenesis
are similar to the case of the two-step PTs. In addition, the gravitational
wave spectra can have one or two peaks through the two-step and the three-step
PTs, and we discuss the detectability at the future gravitational wave
detectors.
| [
{
"created": "Thu, 9 Feb 2023 13:50:36 GMT",
"version": "v1"
}
] | 2023-02-10 | [
[
"Liu",
"Songtao",
""
],
[
"Wang",
"Lei",
""
]
] | In a singlet pseudoscalar extension of the two-Higgs-doublet model we discuss spontaneous CP violation electroweak baryogenesis via two different patterns of phase transitions (PTs): (i) two-step PTs whose first-step and second-step are strongly first-order; (ii) three-step PTs whose first-step is second-order and the second-step and third-step are strongly first-order. For the case of the two-step pattern, the first-step PT takes place at a high temperature, converting the origin phase into an electroweak symmetry broken phase and breaking the CP symmetry spontaneously. Thus, the baryon number is produced during the first-step PT. At the second-step PT, the phase is converted into the observed vacuum at zero temperature, and the CP-symmetry is restored. In both phases the sphaleron processes are sufficiently suppressed, which keep the baryon number unchanged. For the case of the three-step PTs, the pseudoscalar field firstly acquires a nonzero VEV, and VEVs of other fields still remain zero during the first-step PT. The following PTs and electroweak baryogenesis are similar to the case of the two-step PTs. In addition, the gravitational wave spectra can have one or two peaks through the two-step and the three-step PTs, and we discuss the detectability at the future gravitational wave detectors. |
1707.01319 | Zahra Ghalenovi | Zahra Ghalenovi | Study of Electromagnetic Properties of Light Baryons in the Hypercentral
Approach | null | Int J Theor Phys 57, 9 (2018) | 10.1007/s10773-018-3783-6 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Light flavour baryons are studied in a non-relativistic potential model with
colour Coulomb plus linear confinement potential using a simple variational
method. The ground-state masses and magnetic moments of the light baryons are
computed using a spin- and isospin-dependent potential. We extend our scheme to
predict the transition magnetic moments of $B_{(J^P={3/2}^+)} \rightarrow
B_{(J^P={1/2}^+)}\gamma$ processes. We also compute the radiative decay widths
and branching ratios of light baryons. A comparison of our results with those
of other works and experimental data is also presented.
| [
{
"created": "Wed, 5 Jul 2017 11:07:21 GMT",
"version": "v1"
}
] | 2021-11-10 | [
[
"Ghalenovi",
"Zahra",
""
]
] | Light flavour baryons are studied in a non-relativistic potential model with colour Coulomb plus linear confinement potential using a simple variational method. The ground-state masses and magnetic moments of the light baryons are computed using a spin- and isospin-dependent potential. We extend our scheme to predict the transition magnetic moments of $B_{(J^P={3/2}^+)} \rightarrow B_{(J^P={1/2}^+)}\gamma$ processes. We also compute the radiative decay widths and branching ratios of light baryons. A comparison of our results with those of other works and experimental data is also presented. |
hep-ph/0402264 | Alexei Smirnov Yu | A. Yu. Smirnov | Neutrinos: "...annus mirabilis" | 22 pages, latex, 11 figures. Talk given at the 2nd Int. Workshop on
Neutrino oscillations in Venice (NOVE) December 3-5, 2003, Venice, Italy | null | null | null | hep-ph | null | Main results and achievements of 2002 - 2003 in neutrino physics are
summarized. The field moves quickly to new phase with clear experimental and
phenomenological programs, and with new theoretical puzzle which may lead us to
discoveries of the fundamental importance. One of the main results is amazing
pattern of the lepton mixing which emerges from the data. The key questions
are: Does lepton mixing imply new symmetry of Nature? Is the large (maximal?)
mixing related to degeneracy of the neutrino mass spectrum? In this connection
priorities of the future studies are formulated.
| [
{
"created": "Wed, 25 Feb 2004 16:48:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Smirnov",
"A. Yu.",
""
]
] | Main results and achievements of 2002 - 2003 in neutrino physics are summarized. The field moves quickly to new phase with clear experimental and phenomenological programs, and with new theoretical puzzle which may lead us to discoveries of the fundamental importance. One of the main results is amazing pattern of the lepton mixing which emerges from the data. The key questions are: Does lepton mixing imply new symmetry of Nature? Is the large (maximal?) mixing related to degeneracy of the neutrino mass spectrum? In this connection priorities of the future studies are formulated. |
0904.1378 | Ernest Ma | Ernest Ma (UC Riverside) | Variants of the Dark Left-Right Gauge Model: Neutrinos and Scotinos | 9 pages, 1 figure, 2 references added | Phys.Rev.D79:117701,2009 | 10.1103/PhysRevD.79.117701 | UCRHEP-T464 (April 2009) | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the recently proposed dark left-right gauge model (DLRM) of particle
interactions, the usual left-handed lepton doublet (nu,e)_L transforming under
SU(2)_L is accompanied by the UNUSUAL right-handed fermion doublet (n,e)_R
transforming under SU(2)_R, where n_R is NOT the Dirac mass partner of nu_L. In
this scenario, whereas nu_L is certainly a neutrino, n_R should be considered a
SCOTINO, i.e. a dark-matter fermion. Variants of this basic idea are discussed,
including its minimal SCOTOGENIC realization.
| [
{
"created": "Wed, 8 Apr 2009 16:38:53 GMT",
"version": "v1"
},
{
"created": "Sun, 19 Apr 2009 15:25:52 GMT",
"version": "v2"
}
] | 2009-07-09 | [
[
"Ma",
"Ernest",
"",
"UC Riverside"
]
] | In the recently proposed dark left-right gauge model (DLRM) of particle interactions, the usual left-handed lepton doublet (nu,e)_L transforming under SU(2)_L is accompanied by the UNUSUAL right-handed fermion doublet (n,e)_R transforming under SU(2)_R, where n_R is NOT the Dirac mass partner of nu_L. In this scenario, whereas nu_L is certainly a neutrino, n_R should be considered a SCOTINO, i.e. a dark-matter fermion. Variants of this basic idea are discussed, including its minimal SCOTOGENIC realization. |
2102.13053 | Fei Gao | Fei Gao, Joannis Papavassiliou, Jan M. Pawlowski | Fully coupled functional equations for the quark sector of QCD | 72 pages, 30 figures. Version including minor changes of version
published in PRD. For the benefit of the reader we have also added an
Appendix, that contains many more details of the renormalization scheme
(MOM${}^2$ scheme) used in this work. In particular we provide a comparison
with MOM scheme results in the literature (Appendix A2), as well as the
derivation of the RG scheme (Appendix A3) | Phys. Rev. D 103, 094013 (2021) | 10.1103/PhysRevD.103.094013 | null | hep-ph hep-lat hep-th nucl-th | http://creativecommons.org/licenses/by/4.0/ | We present a comprehensive study of the quark sector of $2+1$ flavour QCD,
based on a self-consistent treatment of the coupled system of Schwinger-Dyson
equations for the quark propagator and the full quark-gluon vertex. The
individual form factors of the quark-gluon vertex are expressed in a special
tensor basis obtained from a set of gauge-invariant operators. The sole
external ingredient used as input to our equations is the Landau gauge gluon
propagator with $2+1$ dynamical quark flavours, obtained from studies with
Schwinger-Dyson equations, the functional renormalisation group approach, and
large volume lattice simulations. The appropriate renormalisation procedure
required in order to self-consistently accommodate external inputs stemming
from other functional approaches or the lattice is discussed in detail, and the
value of the gauge coupling is accurately determined at two vastly separated
renormalisation group scales.
Our analysis establishes a clear hierarchy among the vertex form factors. We
identify only three dominant ones, in agreement with previous results. The
components of the quark propagator obtained from our approach are in excellent
agreement with the results from Schwinger-Dyson equations, the functional
renormalisation group, and lattice QCD simulation, a simple benchmark
observable being the chiral condensate in the chiral limit, which is computed
as $(245\,\textrm{MeV})^3$. The present approach has a wide range of
applications, including the self-consistent computation of bound-state
properties and finite temperature and density physics, which are briefly
discussed.
| [
{
"created": "Thu, 25 Feb 2021 18:05:55 GMT",
"version": "v1"
},
{
"created": "Mon, 5 Jul 2021 14:00:36 GMT",
"version": "v2"
}
] | 2021-07-06 | [
[
"Gao",
"Fei",
""
],
[
"Papavassiliou",
"Joannis",
""
],
[
"Pawlowski",
"Jan M.",
""
]
] | We present a comprehensive study of the quark sector of $2+1$ flavour QCD, based on a self-consistent treatment of the coupled system of Schwinger-Dyson equations for the quark propagator and the full quark-gluon vertex. The individual form factors of the quark-gluon vertex are expressed in a special tensor basis obtained from a set of gauge-invariant operators. The sole external ingredient used as input to our equations is the Landau gauge gluon propagator with $2+1$ dynamical quark flavours, obtained from studies with Schwinger-Dyson equations, the functional renormalisation group approach, and large volume lattice simulations. The appropriate renormalisation procedure required in order to self-consistently accommodate external inputs stemming from other functional approaches or the lattice is discussed in detail, and the value of the gauge coupling is accurately determined at two vastly separated renormalisation group scales. Our analysis establishes a clear hierarchy among the vertex form factors. We identify only three dominant ones, in agreement with previous results. The components of the quark propagator obtained from our approach are in excellent agreement with the results from Schwinger-Dyson equations, the functional renormalisation group, and lattice QCD simulation, a simple benchmark observable being the chiral condensate in the chiral limit, which is computed as $(245\,\textrm{MeV})^3$. The present approach has a wide range of applications, including the self-consistent computation of bound-state properties and finite temperature and density physics, which are briefly discussed. |
hep-ph/0011035 | Volodymyr Magas | R. Fiore, L.L. Jenkovszky, V. Magas, F. Paccanoni and A. Papa | Analytic model of Regge trajectories | 17 pages, 3 figures | Eur.Phys.J. A10 (2001) 217-221 | 10.1007/s100500170133 | null | hep-ph | null | A model for a Regge trajectory compatible with the threshold behavior
required by unitarity and asymptotics in agreement with analyticity constraints
is given in explicit form. The model is confronted in the time-like region with
widths and masses of the mesonic resonances and, in the space-like region, the
$\rho$ trajectory is compared with predictions derived from $\pi-N$
charge-exchange reaction. Breaking of the exchange degeneracy is studied in the
model and its effect on both the masses and widths is determined.
| [
{
"created": "Thu, 2 Nov 2000 14:32:28 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Fiore",
"R.",
""
],
[
"Jenkovszky",
"L. L.",
""
],
[
"Magas",
"V.",
""
],
[
"Paccanoni",
"F.",
""
],
[
"Papa",
"A.",
""
]
] | A model for a Regge trajectory compatible with the threshold behavior required by unitarity and asymptotics in agreement with analyticity constraints is given in explicit form. The model is confronted in the time-like region with widths and masses of the mesonic resonances and, in the space-like region, the $\rho$ trajectory is compared with predictions derived from $\pi-N$ charge-exchange reaction. Breaking of the exchange degeneracy is studied in the model and its effect on both the masses and widths is determined. |
hep-ph/0605236 | Andre Sopczak | Andre Sopczak | New Physics Searches at the Tevatron and the LHC | 32 pages, 44 figures, presented at PHENO'05 and Aspen Collider
Physics Workshop 2005 | null | null | null | hep-ph | null | The Tevatron Run-II started data-taking in spring 2001 and several searches
for new particles have been performed. The preliminary 2005 results are
concisely reviewed for the experiments CDF and D0. Model-independent and
model-dependent limits on Higgs boson and Supersymmetric particle production
are set and interpretations are given. Several limits from the LEP era have
been extended. The outlook for the Tevatron and the prospects for the ATLAS and
CMS experiments at the LHC for selected searches are briefly addressed.
| [
{
"created": "Mon, 22 May 2006 19:51:52 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Sopczak",
"Andre",
""
]
] | The Tevatron Run-II started data-taking in spring 2001 and several searches for new particles have been performed. The preliminary 2005 results are concisely reviewed for the experiments CDF and D0. Model-independent and model-dependent limits on Higgs boson and Supersymmetric particle production are set and interpretations are given. Several limits from the LEP era have been extended. The outlook for the Tevatron and the prospects for the ATLAS and CMS experiments at the LHC for selected searches are briefly addressed. |
hep-ph/9910392 | Christopher D. Carone | Alfredo Aranda, Christopher D. Carone, and Richard F. Lebed | U(2) Flavor Physics without U(2) Symmetry | 12 pages RevTeX, 1 eps figure. A few typos corrected | Phys.Lett.B474:170-176,2000 | 10.1016/S0370-2693(99)01497-5 | WM-99-117, JLAB-THY-99-31 | hep-ph | null | We present a model of fermion masses based on a minimal, non-Abelian discrete
symmetry that reproduces the Yukawa matrices usually associated with U(2)
theories of flavor. Mass and mixing angle relations that follow from the simple
form of the quark and charged lepton Yukawa textures are therefore common to
both theories. We show that the differing representation structure of our
horizontal symmetry allows for new solutions to the solar and atmospheric
neutrino problems that do not involve modification of the original charged
fermion Yukawa textures, or the introduction of sterile neutrinos.
| [
{
"created": "Tue, 19 Oct 1999 01:18:54 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Jan 2000 19:39:22 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Aranda",
"Alfredo",
""
],
[
"Carone",
"Christopher D.",
""
],
[
"Lebed",
"Richard F.",
""
]
] | We present a model of fermion masses based on a minimal, non-Abelian discrete symmetry that reproduces the Yukawa matrices usually associated with U(2) theories of flavor. Mass and mixing angle relations that follow from the simple form of the quark and charged lepton Yukawa textures are therefore common to both theories. We show that the differing representation structure of our horizontal symmetry allows for new solutions to the solar and atmospheric neutrino problems that do not involve modification of the original charged fermion Yukawa textures, or the introduction of sterile neutrinos. |
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