id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0810.1037 | Deniz Yilmaz | D. Yilmaz | Joint analysis of solar neutrino and new KamLAND data in the RSFP
framework | 11 pages, 4 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A joint analysis of solar neutrino data together with the new KamLAND data is
presented in the RSFP framework. It is investigated that how the new KamLAND
data effects the allowed regions at different $\mu B$ values. A limit on $\mu
B$ value is found at the different confidence level intervals. It is shown that
the RSFP scenerio does not have a crucial role on the solar neutrino data.
| [
{
"created": "Mon, 6 Oct 2008 18:41:18 GMT",
"version": "v1"
}
] | 2008-10-07 | [
[
"Yilmaz",
"D.",
""
]
] | A joint analysis of solar neutrino data together with the new KamLAND data is presented in the RSFP framework. It is investigated that how the new KamLAND data effects the allowed regions at different $\mu B$ values. A limit on $\mu B$ value is found at the different confidence level intervals. It is shown that the RSFP scenerio does not have a crucial role on the solar neutrino data. |
1612.01309 | Jonas Wittbrodt | Margarete Muhlleitner, Marco O.P. Sampaio, Rui Santos, Jonas Wittbrodt | The N2HDM under Theoretical and Experimental Scrutiny | 36 pages, 11 figures, 6 tables. The N2HDECAY code and documentation
can be found at https://gitlab.com/jonaswittbrodt/N2HDECAY . The N2HDM scan
model implementation in ScannerS can be found at
http://scanners.hepforge.org/ . Fixed typos in the conditions for boundedness
and perturbative unitarity | JHEP 1703 (2017) 094 | 10.1007/JHEP03(2017)094 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The N2HDM is based on the CP-conserving 2HDM extended by a real scalar
singlet field. Its enlarged parameter space and its fewer symmetry conditions
as compared to supersymmetric models allow for an interesting phenomenology
compatible with current experimental constraints, while adding to the 2HDM
sector the possibility of Higgs-to-Higgs decays with three different Higgs
bosons. In this paper the N2HDM is subjected to detailed scrutiny. Regarding
the theoretical constraints we implement tests of tree-level perturbativity and
vacuum stability. Moreover, we present, for the first time, a thorough analysis
of the global minimum of the N2HDM. The model and the theoretical constraints
have been implemented in ScannerS, and we provide N2HDECAY, a code based on
HDECAY, for the computation of the N2HDM branching ratios and total widths
including the state-of-the-art higher order QCD corrections and off-shell
decays. We then perform an extensive parameter scan in the N2HDM parameter
space, with all theoretical and experimental constraints applied, and analyse
its allowed regions. We find that large singlet admixtures are still compatible
with the Higgs data and investigate which observables will allow to restrict
the singlet nature most effectively in the next runs of the LHC. Similarly to
the 2HDM, the N2HDM exhibits a wrong-sign parameter regime, which will be
constrained by future Higgs precision measurements.
| [
{
"created": "Mon, 5 Dec 2016 11:21:59 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Apr 2017 10:18:06 GMT",
"version": "v2"
},
{
"created": "Thu, 29 Jun 2017 14:36:32 GMT",
"version": "v3"
},
{
"created": "Tue, 1 Oct 2019 09:06:14 GMT",
"version": "v4"
}
] | 2019-10-02 | [
[
"Muhlleitner",
"Margarete",
""
],
[
"Sampaio",
"Marco O. P.",
""
],
[
"Santos",
"Rui",
""
],
[
"Wittbrodt",
"Jonas",
""
]
] | The N2HDM is based on the CP-conserving 2HDM extended by a real scalar singlet field. Its enlarged parameter space and its fewer symmetry conditions as compared to supersymmetric models allow for an interesting phenomenology compatible with current experimental constraints, while adding to the 2HDM sector the possibility of Higgs-to-Higgs decays with three different Higgs bosons. In this paper the N2HDM is subjected to detailed scrutiny. Regarding the theoretical constraints we implement tests of tree-level perturbativity and vacuum stability. Moreover, we present, for the first time, a thorough analysis of the global minimum of the N2HDM. The model and the theoretical constraints have been implemented in ScannerS, and we provide N2HDECAY, a code based on HDECAY, for the computation of the N2HDM branching ratios and total widths including the state-of-the-art higher order QCD corrections and off-shell decays. We then perform an extensive parameter scan in the N2HDM parameter space, with all theoretical and experimental constraints applied, and analyse its allowed regions. We find that large singlet admixtures are still compatible with the Higgs data and investigate which observables will allow to restrict the singlet nature most effectively in the next runs of the LHC. Similarly to the 2HDM, the N2HDM exhibits a wrong-sign parameter regime, which will be constrained by future Higgs precision measurements. |
hep-ph/9710355 | Shaouly Bar-Shalom | Shaouly Bar-Shalom | Probing New Higgs-Top Interactions at the Tree-Level in a Future e^+e^-
Collider | 25 pages, latex, 7 figures embadded in the text using epsfig.
Expanded version of a talk presented at the International Europhysics
Conference on High Energy Physics, EPS-HEP97, August 19-26, 1997, Jerusalem,
Israel | null | null | UCRHEP-T206 | hep-ph | null | The possibility of observing large signatures of new CP-violating and
flavor-changing Higgs-Top couplings in a future e^+e^- collider experiments
such as e^+e^- -> t bar-t h, t bar-t Z and e^+e^- -> t bar-c \nu_e bar-\nu_e, t
bar-c e^+ e^- is discussed. Such, beyond the Standard Model, couplings can
occur already at the tree-level within a class of Two Higgs Doublets Models.
Therefore, an extremely interesting feature of those reactions is that the
CP-violating and flavor-changing effects are governed by tree-level dynamics.
These reactions may therefore serve as unique avenues for searching for new
phenomena associated with Two Higgs Doublets Models and, as is shown here,
could yield statistically significant signals of new physics. We find that the
CP-asymmetries in e^+e^- -> t bar-t h, t bar-t Z can reach tens of percents,
and the flavor changing cross-section of e^+e^- -> t bar-c \nu_e bar-\nu_e is
typically a few fb's, for light Higgs mass around the electroweak scale.
| [
{
"created": "Tue, 14 Oct 1997 21:41:14 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bar-Shalom",
"Shaouly",
""
]
] | The possibility of observing large signatures of new CP-violating and flavor-changing Higgs-Top couplings in a future e^+e^- collider experiments such as e^+e^- -> t bar-t h, t bar-t Z and e^+e^- -> t bar-c \nu_e bar-\nu_e, t bar-c e^+ e^- is discussed. Such, beyond the Standard Model, couplings can occur already at the tree-level within a class of Two Higgs Doublets Models. Therefore, an extremely interesting feature of those reactions is that the CP-violating and flavor-changing effects are governed by tree-level dynamics. These reactions may therefore serve as unique avenues for searching for new phenomena associated with Two Higgs Doublets Models and, as is shown here, could yield statistically significant signals of new physics. We find that the CP-asymmetries in e^+e^- -> t bar-t h, t bar-t Z can reach tens of percents, and the flavor changing cross-section of e^+e^- -> t bar-c \nu_e bar-\nu_e is typically a few fb's, for light Higgs mass around the electroweak scale. |
2105.09873 | Fredrick Olness | nCTEQ Collaboration: P. Duwent\"aster, L. A. Husov\'a, T. Je\v{z}o, M.
Klasen, K. Kova\v{r}\'ik, A. Kusina, K. F. Muzakka, F. I. Olness, I.
Schienbein, J. Y. Yu | Impact of inclusive hadron production data on nuclear gluon PDFs | 23 pages, 17 figures, 5 tables. Minor updates to align with journal
version | Phys.Rev.D 104 (2021) 9, 094005 | 10.1103/PhysRevD.104.094005 | KA-TP-10-2021, MS-TP-21-11, P3H-21-033,
SMU-HEP-21-05,IFJPAN-IV-2021-9 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A precise knowledge of nuclear parton distribution functions (nPDFs) is --
among other things -- important for the unambiguous interpretation of hard
process data taken in pA and AA collisions at the Relativistic Heavy Ion
Collider (RHIC) and the Large Hadron Collider (LHC). The available fixed target
data for deep inelastic scattering (DIS) and Drell-Yan (DY) lepton pair
production mainly constrain the light quark distributions. It is hence crucial
to include more and more collider data in global analyses of nPDFs in order to
better pin down the different parton flavors, in particular the gluon
distribution at small x. To help constrain the nuclear gluon PDF, we extend the
nCTEQ15 analysis by including single inclusive hadron (SIH) production data
from RHIC (PHENIX and STAR) and LHC (ALICE). In addition to the DIS, DY and SIH
data sets, we will also include LHC W/Z production data. As the SIH calculation
is dependent on hadronic fragmentation functions (FFs), we use a variety of FFs
available in the literature to properly estimate this source of uncertainty. We
study the impact of these data on the PDFs, and compare with both the nCTEQ15
and nCTEQ15WZ sets. The calculations are performed using a new implementation
of the nCTEQ code (nCTEQ++) including a modified version of INCNLO which allows
faster calculations using pre-computed grids. The extension of the nCTEQ15
analysis to include the SIH data represents an important step toward the next
generation of PDFs.
| [
{
"created": "Thu, 20 May 2021 16:23:07 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Dec 2021 02:54:02 GMT",
"version": "v2"
}
] | 2021-12-02 | [
[
"nCTEQ Collaboration",
"",
""
],
[
"Duwentäster",
"P.",
""
],
[
"Husová",
"L. A.",
""
],
[
"Ježo",
"T.",
""
],
[
"Klasen",
"M.",
""
],
[
"Kovařík",
"K.",
""
],
[
"Kusina",
"A.",
""
],
[
"Muzakka",
"K. F.",
""
],
[
"Olness",
"F. I.",
""
],
[
"Schienbein",
"I.",
""
],
[
"Yu",
"J. Y.",
""
]
] | A precise knowledge of nuclear parton distribution functions (nPDFs) is -- among other things -- important for the unambiguous interpretation of hard process data taken in pA and AA collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). The available fixed target data for deep inelastic scattering (DIS) and Drell-Yan (DY) lepton pair production mainly constrain the light quark distributions. It is hence crucial to include more and more collider data in global analyses of nPDFs in order to better pin down the different parton flavors, in particular the gluon distribution at small x. To help constrain the nuclear gluon PDF, we extend the nCTEQ15 analysis by including single inclusive hadron (SIH) production data from RHIC (PHENIX and STAR) and LHC (ALICE). In addition to the DIS, DY and SIH data sets, we will also include LHC W/Z production data. As the SIH calculation is dependent on hadronic fragmentation functions (FFs), we use a variety of FFs available in the literature to properly estimate this source of uncertainty. We study the impact of these data on the PDFs, and compare with both the nCTEQ15 and nCTEQ15WZ sets. The calculations are performed using a new implementation of the nCTEQ code (nCTEQ++) including a modified version of INCNLO which allows faster calculations using pre-computed grids. The extension of the nCTEQ15 analysis to include the SIH data represents an important step toward the next generation of PDFs. |
1108.1767 | Ana Carolina Bruno Machado Miss | A. C. B. Machado, J. C. Montero and V. Pleitez | On fermion masses and mixing in a model with $A_4$ symmetry | Version accepted for publication in International Journal of Modern
Physics A. In this version we added a discussion on the charged lepton and
neutrino masses. The title has been changed. Other minor changes do not
modify the conclusions | null | 10.1142/S0217751X12500686 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a recently proposed multi-Higgs extension of the standard model in which
discrete symmetries, $A_4$ and $Z_3$ are imposed we show that, after
accommodating the fermion masses and the mixing matrices in the charged
currents, the mixing matrices in the neutral currents induced by neutral
scalars are numerically obtained. However, the flavor changing neutral currents
are under control mainly by mixing and/or mass suppressions in the neutral
scalar sector.
| [
{
"created": "Mon, 8 Aug 2011 18:04:18 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Apr 2012 19:04:02 GMT",
"version": "v2"
}
] | 2012-04-25 | [
[
"Machado",
"A. C. B.",
""
],
[
"Montero",
"J. C.",
""
],
[
"Pleitez",
"V.",
""
]
] | In a recently proposed multi-Higgs extension of the standard model in which discrete symmetries, $A_4$ and $Z_3$ are imposed we show that, after accommodating the fermion masses and the mixing matrices in the charged currents, the mixing matrices in the neutral currents induced by neutral scalars are numerically obtained. However, the flavor changing neutral currents are under control mainly by mixing and/or mass suppressions in the neutral scalar sector. |
2102.00110 | Dmitri Kharzeev | Dmitri E. Kharzeev | The mass radius of the proton | 20 pages, 3 figures; 2 typos fixed | Phys. Rev. D 104, 054015 (2021) | 10.1103/PhysRevD.104.054015 | null | hep-ph hep-lat nucl-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | The mass radius is a fundamental property of the proton that so far has not
been determined from experiment. Here we show that the mass radius of the
proton can be rigorously defined through the formfactor of the trace of the
energy-momentum tensor (EMT) of QCD in the weak gravitational field
approximation, as appropriate for this problem. We then demonstrate that the
scale anomaly of QCD enables the extraction of the formfactor of the trace of
the EMT from the data on threshold photoproduction of $J/\psi$ and $\Upsilon$
quarkonia, and use the recent GlueX Collaboration data to extract the r.m.s.
mass radius of the proton ${\rm R_m = 0.55 \pm 0.03 \ fm}$. The extracted mass
radius is significantly smaller than the charge radius of the proton ${\rm R_C
= 0.8409 \pm 0.0004 \ fm}$. We attribute this difference to the interplay of
asymptotic freedom and spontaneous breaking of chiral symmetry in QCD, and
outline future measurements needed to determine the mass radius more precisely.
| [
{
"created": "Fri, 29 Jan 2021 23:42:24 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Feb 2021 19:59:30 GMT",
"version": "v2"
}
] | 2021-09-22 | [
[
"Kharzeev",
"Dmitri E.",
""
]
] | The mass radius is a fundamental property of the proton that so far has not been determined from experiment. Here we show that the mass radius of the proton can be rigorously defined through the formfactor of the trace of the energy-momentum tensor (EMT) of QCD in the weak gravitational field approximation, as appropriate for this problem. We then demonstrate that the scale anomaly of QCD enables the extraction of the formfactor of the trace of the EMT from the data on threshold photoproduction of $J/\psi$ and $\Upsilon$ quarkonia, and use the recent GlueX Collaboration data to extract the r.m.s. mass radius of the proton ${\rm R_m = 0.55 \pm 0.03 \ fm}$. The extracted mass radius is significantly smaller than the charge radius of the proton ${\rm R_C = 0.8409 \pm 0.0004 \ fm}$. We attribute this difference to the interplay of asymptotic freedom and spontaneous breaking of chiral symmetry in QCD, and outline future measurements needed to determine the mass radius more precisely. |
0710.2078 | Hooman Davoudiasl | Hooman Davoudiasl, Thomas G. Rizzo, and Amarjit Soni | On Direct Verification of Warped Hierarchy-and-Flavor Models | Revtex4, 21 pages, 11 figures | Phys.Rev.D77:036001,2008 | 10.1103/PhysRevD.77.036001 | BNL-HET-07/16, SLAC-PUB-12855 | hep-ph | null | We consider direct experimental verification of warped models, based on the
Randall-Sundrum (RS) scenario, that explain gauge and flavor hierarchies,
assuming that the gauge fields and fermions of the Standard Model (SM)
propagate in the 5D bulk. Most studies have focused on the bosonic Kaluza Klein
(KK) signatures and indicate that discovering gauge KK modes is likely
possible, yet challenging, while graviton KK modes are unlikely to be
accessible at the LHC, even with a luminosity upgrade. We show that direct
evidence for bulk SM fermions, {\it i.e.} their KK modes, is likely also beyond
the reach of a luminosity-upgraded LHC. Thus, neither the spin-2 KK graviton,
the most distinct RS signal, nor the KK SM fermions, direct evidence for bulk
flavor, seem to be within the reach of the LHC. We then consider hadron
colliders with $\sqrt{s} =$ 21, 28, and 60 TeV. We find that discovering the
first KK modes of SM fermions and the graviton typically requires the Next
Hadron Collider (NHC) with $\sqrt{s} \approx 60$ TeV and ${\cal O}(1)$
ab$^{-1}$ of integrated luminosity. If the LHC yields hints of these warped
models, establishing that Nature is described by them, or their 4D CFT duals,
requires an NHC-class machine in the post-LHC experimental program.
| [
{
"created": "Wed, 10 Oct 2007 17:52:26 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Davoudiasl",
"Hooman",
""
],
[
"Rizzo",
"Thomas G.",
""
],
[
"Soni",
"Amarjit",
""
]
] | We consider direct experimental verification of warped models, based on the Randall-Sundrum (RS) scenario, that explain gauge and flavor hierarchies, assuming that the gauge fields and fermions of the Standard Model (SM) propagate in the 5D bulk. Most studies have focused on the bosonic Kaluza Klein (KK) signatures and indicate that discovering gauge KK modes is likely possible, yet challenging, while graviton KK modes are unlikely to be accessible at the LHC, even with a luminosity upgrade. We show that direct evidence for bulk SM fermions, {\it i.e.} their KK modes, is likely also beyond the reach of a luminosity-upgraded LHC. Thus, neither the spin-2 KK graviton, the most distinct RS signal, nor the KK SM fermions, direct evidence for bulk flavor, seem to be within the reach of the LHC. We then consider hadron colliders with $\sqrt{s} =$ 21, 28, and 60 TeV. We find that discovering the first KK modes of SM fermions and the graviton typically requires the Next Hadron Collider (NHC) with $\sqrt{s} \approx 60$ TeV and ${\cal O}(1)$ ab$^{-1}$ of integrated luminosity. If the LHC yields hints of these warped models, establishing that Nature is described by them, or their 4D CFT duals, requires an NHC-class machine in the post-LHC experimental program. |
2212.13029 | Chikako Idegawa | Gi-Chol Cho, Chikako Idegawa, Rio Sugihara | A complex singlet extension of the Standard Model and Multi-critical
Point Principle | 19 pages, 3 figures | null | 10.1016/j.physletb.2023.137757 | OCHA-PP-374 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the Multi-critical Point Principle (MPP) in a complex singlet scalar
extension of the Standard Model (CxSM). The MPP discussed in this study selects
model parameters so that two low-energy vacua realized by scalar fields are
degenerate. We further note that the MPP may inhibit the electroweak phase
transition (EWPT) in a certain class of models where the tree-level potential
plays an essential role in its realization. Despite that, we show that strong
first-order EWPT still occurs even after imposing the MPP to the scalar
potential of the CxSM due to the 1-loop corrections by the new scalar boson. We
study the allowed parameter space where a mass of the additional scalar is
degenerate with that of the Standard Model Higgs boson, which provides a
built-in mechanism to circumvent constraints from dark matter direct detection
experiments. The parameter space for the non-degenerate scalar scenario is also
studied for comparison.
| [
{
"created": "Mon, 26 Dec 2022 07:34:46 GMT",
"version": "v1"
}
] | 2023-03-01 | [
[
"Cho",
"Gi-Chol",
""
],
[
"Idegawa",
"Chikako",
""
],
[
"Sugihara",
"Rio",
""
]
] | We study the Multi-critical Point Principle (MPP) in a complex singlet scalar extension of the Standard Model (CxSM). The MPP discussed in this study selects model parameters so that two low-energy vacua realized by scalar fields are degenerate. We further note that the MPP may inhibit the electroweak phase transition (EWPT) in a certain class of models where the tree-level potential plays an essential role in its realization. Despite that, we show that strong first-order EWPT still occurs even after imposing the MPP to the scalar potential of the CxSM due to the 1-loop corrections by the new scalar boson. We study the allowed parameter space where a mass of the additional scalar is degenerate with that of the Standard Model Higgs boson, which provides a built-in mechanism to circumvent constraints from dark matter direct detection experiments. The parameter space for the non-degenerate scalar scenario is also studied for comparison. |
hep-ph/0410176 | Anindya Datta | Anindya Datta, Daniele Fargion, Barbara Mele | SUSY Resonances from UHE neutralinos in Neutrino Telescopes and in the
Sky | 23 pages, 4 figures; one reference added | JHEP0509:007,2005 | 10.1088/1126-6708/2005/09/007 | null | hep-ph astro-ph hep-ex | null | In the Top-down scenarios, the decay of super-heavy particles
(m~10^{12-16}GeV), situated in dark-matter halos not very far from our Galaxy,
can explain the ultra-high-energy (UHE) cosmic-ray spectrum beyond the
Griesen-Zatasepin-Kuzmin cut-off. In the MSSM, a major component of the UHE
cosmic-ray flux at PeV-EeV energies could be given by the lightest neutralino
\chi, that is the lightest stable supersymmetric particle. Then, the signal of
UHE \chi's on earth might emerge over the interactions of a comparable neutrino
component. We compute the event rates for the resonant production of "right"
selectrons and "right" squarks in mSUGRA, when UHE neutralinos of energy larger
than 10^5 GeV scatter off electrons and quarks in an earth-based detector like
IceCube. When the resonant channel dominates in the total \chi-e,\chi-q
scattering cross section, the only model parameters affecting the corresponding
visible signal rates turn out to be the physical masses of the resonant
right-scalar and of the lightest neutralino. We compare the expected number of
supersymmetric events with the rates corresponding to the expected Glashow W
resonance and to the continuum UHE \nu-N scattering for realistic power-law
spectra. We find that the event rate in the leptonic selectron channel is
particularly promising, and can reach a few tens for a one-year exposure in
IceCube. Finally, we note that UHE neutralinos at much higher energies (up to
hundreds ZeV) may produce sneutrino resonances by scattering off relic
neutrinos in the Local Group hot dark halo. The consequent \tilde{\nu}-burst
into hadronic final states could mimic Z-burst events, although with quite
smaller conversion efficiency.
| [
{
"created": "Tue, 12 Oct 2004 19:20:39 GMT",
"version": "v1"
},
{
"created": "Mon, 5 Sep 2005 08:34:38 GMT",
"version": "v2"
},
{
"created": "Thu, 15 Sep 2005 11:08:00 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Datta",
"Anindya",
""
],
[
"Fargion",
"Daniele",
""
],
[
"Mele",
"Barbara",
""
]
] | In the Top-down scenarios, the decay of super-heavy particles (m~10^{12-16}GeV), situated in dark-matter halos not very far from our Galaxy, can explain the ultra-high-energy (UHE) cosmic-ray spectrum beyond the Griesen-Zatasepin-Kuzmin cut-off. In the MSSM, a major component of the UHE cosmic-ray flux at PeV-EeV energies could be given by the lightest neutralino \chi, that is the lightest stable supersymmetric particle. Then, the signal of UHE \chi's on earth might emerge over the interactions of a comparable neutrino component. We compute the event rates for the resonant production of "right" selectrons and "right" squarks in mSUGRA, when UHE neutralinos of energy larger than 10^5 GeV scatter off electrons and quarks in an earth-based detector like IceCube. When the resonant channel dominates in the total \chi-e,\chi-q scattering cross section, the only model parameters affecting the corresponding visible signal rates turn out to be the physical masses of the resonant right-scalar and of the lightest neutralino. We compare the expected number of supersymmetric events with the rates corresponding to the expected Glashow W resonance and to the continuum UHE \nu-N scattering for realistic power-law spectra. We find that the event rate in the leptonic selectron channel is particularly promising, and can reach a few tens for a one-year exposure in IceCube. Finally, we note that UHE neutralinos at much higher energies (up to hundreds ZeV) may produce sneutrino resonances by scattering off relic neutrinos in the Local Group hot dark halo. The consequent \tilde{\nu}-burst into hadronic final states could mimic Z-burst events, although with quite smaller conversion efficiency. |
1410.0505 | Sophia Borowka | S. Borowka | Momentum Dependent Two-Loop Corrections to the Neutral Higgs Boson
Masses in the MSSM | 8 pages, 3 figures, contribution to the proceedings of the Loops and
Legs 2014 conference | null | null | MPP-2014-364 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The momentum dependent two-loop contributions of the order
$\mathcal{O}$($\alpha_s \alpha_t$) to the masses in the Higgs-boson sector of
the MSSM are computed. Adopting the Feynman-diagrammatic approach and using a
mixed on-shell/$\overline{DR}$ renormalization scheme, the new corrections can
directly be matched onto the higher-order corrections included in the code
FeynHiggs. Two-loop diagrams involving several mass scales are evaluated with
the program SecDec. The combination of the new momentum dependent two-loop
contribution with the existing one- and two-loop corrections leads to an
improved prediction of the light MSSM Higgs-boson mass with reduced theoretical
uncertainty. The resulting shifts in the lightest Higgs-boson mass $M_h$ can
extend up to the level of the current experimental uncertainty of about 500 MeV
in the scenario considered in these proceedings.
| [
{
"created": "Thu, 2 Oct 2014 10:48:05 GMT",
"version": "v1"
}
] | 2014-10-03 | [
[
"Borowka",
"S.",
""
]
] | The momentum dependent two-loop contributions of the order $\mathcal{O}$($\alpha_s \alpha_t$) to the masses in the Higgs-boson sector of the MSSM are computed. Adopting the Feynman-diagrammatic approach and using a mixed on-shell/$\overline{DR}$ renormalization scheme, the new corrections can directly be matched onto the higher-order corrections included in the code FeynHiggs. Two-loop diagrams involving several mass scales are evaluated with the program SecDec. The combination of the new momentum dependent two-loop contribution with the existing one- and two-loop corrections leads to an improved prediction of the light MSSM Higgs-boson mass with reduced theoretical uncertainty. The resulting shifts in the lightest Higgs-boson mass $M_h$ can extend up to the level of the current experimental uncertainty of about 500 MeV in the scenario considered in these proceedings. |
2311.04849 | Rodolfo Ferro-Hern\'andez | Rodolfo Ferro Hern\'andez | AdlerPy: A Python Package for the Perturbative Adler Function | 6 pages, 5 Figures | null | null | null | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this letter, I give availability to the source code AdlerPy which will
allow to easily use the Adler function. As an application, I use the
mass-dependent perturbative expression for the Adler function to compute
several observables and relevant Standard Model parameters.
| [
{
"created": "Wed, 8 Nov 2023 17:35:11 GMT",
"version": "v1"
}
] | 2023-11-09 | [
[
"Hernández",
"Rodolfo Ferro",
""
]
] | In this letter, I give availability to the source code AdlerPy which will allow to easily use the Adler function. As an application, I use the mass-dependent perturbative expression for the Adler function to compute several observables and relevant Standard Model parameters. |
2212.09756 | Ningqiang Song | Edward Hardy, Ningqiang Song | Listening for Dark Photon Radio from the Galactic Centre | 27 pages, 9 figures, matched journal version | null | 10.1103/PhysRevD.107.115035 | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | Dark photon dark matter that has a kinetic mixing with the Standard Model
photon can resonantly convert in environments where its mass $m_{A'}$ coincides
with the plasma frequency. We show that such conversion in neutron stars or
accreting white dwarfs in the galactic centre can lead to detectable radio
signals. Depending on the dark matter spatial distribution, future radio
telescopes could be sensitive to values of the kinetic mixing parameter that
exceed current constraints by orders of magnitude for $m_{A'} \in \left(6\times
10^{-6},7\times 10^{-4}\right)$ eV.
| [
{
"created": "Mon, 19 Dec 2022 19:00:00 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Sep 2023 15:32:02 GMT",
"version": "v2"
}
] | 2023-09-14 | [
[
"Hardy",
"Edward",
""
],
[
"Song",
"Ningqiang",
""
]
] | Dark photon dark matter that has a kinetic mixing with the Standard Model photon can resonantly convert in environments where its mass $m_{A'}$ coincides with the plasma frequency. We show that such conversion in neutron stars or accreting white dwarfs in the galactic centre can lead to detectable radio signals. Depending on the dark matter spatial distribution, future radio telescopes could be sensitive to values of the kinetic mixing parameter that exceed current constraints by orders of magnitude for $m_{A'} \in \left(6\times 10^{-6},7\times 10^{-4}\right)$ eV. |
hep-ph/0003320 | Jorge Portoles | D. Gomez Dumm, A. Pich, J. Portoles | The hadronic off-shell width of meson resonances | 1+12 pages, 4 figures. Minor changes in text. Conclusions unchanged.
Version accepted for publication in Phys. Rev. D | Phys.Rev. D62 (2000) 054014 | 10.1103/PhysRevD.62.054014 | IFIC/00-19, FTUV/00-0331, TAN-FNT-00-02 | hep-ph | null | Within the resonance chiral effective theory we study the dressed propagators
of the spin-1 fields, as arise from a Dyson-Schwinger resummation
perturbatively constructed from loop diagrams with absorptive contributions in
the s-channel. We apply the procedure to the vector pion form factor and the
elastic pion-pion scattering to obtain the off-shell width of the rho_0 meson.
We adopt a definition of the off-shell width of spin-1 meson resonances that
satisfies the requirements of analyticity, unitarity, chiral symmetry and
asymptotic behaviour ruled by QCD. To fulfil these constraints the resummation
procedure cannot consist only of self-energy diagrams. Our width definition is
shown to be independent of the formulation used to describe the spin-1 meson
resonances.
| [
{
"created": "Fri, 31 Mar 2000 14:10:39 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Jun 2000 07:27:21 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Dumm",
"D. Gomez",
""
],
[
"Pich",
"A.",
""
],
[
"Portoles",
"J.",
""
]
] | Within the resonance chiral effective theory we study the dressed propagators of the spin-1 fields, as arise from a Dyson-Schwinger resummation perturbatively constructed from loop diagrams with absorptive contributions in the s-channel. We apply the procedure to the vector pion form factor and the elastic pion-pion scattering to obtain the off-shell width of the rho_0 meson. We adopt a definition of the off-shell width of spin-1 meson resonances that satisfies the requirements of analyticity, unitarity, chiral symmetry and asymptotic behaviour ruled by QCD. To fulfil these constraints the resummation procedure cannot consist only of self-energy diagrams. Our width definition is shown to be independent of the formulation used to describe the spin-1 meson resonances. |
hep-ph/0007245 | null | A. Denner, S. Dittmaier, M. Roth, D. Wackeroth | Electroweak Precision Physics at e+ e- Colliders with RacoonWW | 12 pages, 13 postscript figures, to appear in the Proceedings of the
22nd annual MRST Conference on Theoretical High Energy Physics (MRST 2000),
Rochester, New York, May 8-9, 2000 | AIPConf.Proc.541:40-50,2000 | 10.1063/1.1328900 | ER/40685/948, UR-1609 | hep-ph | null | We present precise predictions for the processes e+ e- -> WW -> 4f(gamma) at
LEP2 and future Linear-Collider (LC) energies obtained with the Monte Carlo
generator RacoonWW. The program RacoonWW includes the complete O(alpha)
electroweak radiative corrections to e+ e- -> WW -> 4f in the double-pole
approximation (DPA). While the virtual corrections are treated in DPA, the
calculation of the bremsstrahlung corrections is based on the full lowest-order
matrix elements to the processes e+ e- -> 4f+gamma. This asymmetric treatment
of virtual and real photons requires a careful matching of the arising infrared
and collinear singularities. We also take into account higher-order
initial-state photon radiation via the structure-function method. Here, we
briefly describe the RacoonWW approach, give numerical results for the total
W-pair production cross sections, confront them with LEP2 data, and study the
impact of the radiative corrections on angular and W-invariant-mass
distributions at LEP2 and LC energies.
| [
{
"created": "Fri, 21 Jul 2000 22:08:56 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Denner",
"A.",
""
],
[
"Dittmaier",
"S.",
""
],
[
"Roth",
"M.",
""
],
[
"Wackeroth",
"D.",
""
]
] | We present precise predictions for the processes e+ e- -> WW -> 4f(gamma) at LEP2 and future Linear-Collider (LC) energies obtained with the Monte Carlo generator RacoonWW. The program RacoonWW includes the complete O(alpha) electroweak radiative corrections to e+ e- -> WW -> 4f in the double-pole approximation (DPA). While the virtual corrections are treated in DPA, the calculation of the bremsstrahlung corrections is based on the full lowest-order matrix elements to the processes e+ e- -> 4f+gamma. This asymmetric treatment of virtual and real photons requires a careful matching of the arising infrared and collinear singularities. We also take into account higher-order initial-state photon radiation via the structure-function method. Here, we briefly describe the RacoonWW approach, give numerical results for the total W-pair production cross sections, confront them with LEP2 data, and study the impact of the radiative corrections on angular and W-invariant-mass distributions at LEP2 and LC energies. |
1810.07224 | Jack Y. Araz | Jack Y. Araz, Shankha Banerjee, Mariana Frank, Benjamin Fuks, Andreas
Goudelis | Exploring vector-like supersymmetric extensions of the Standard Model
with dark matter and colliders | 18 pages, 5 figures and 5 tables; title changed to "Dark matter and
collider signals in an MSSM extension with vector-like multiplets" in journal
version; minor modifications and clarifications added; conclusions unchanged;
version accepted for publication in PRD | Phys. Rev. D 98, 115009 (2018) | 10.1103/PhysRevD.98.115009 | CUMQ/HEP 199, IPPP/18/95 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by grand unification considerations, we analyze a simple extension
of the minimal supersymmetric standard model with additional pairs of
vector-like chiral supermultiplets. We focus on the so-called LND setup, which
enlarges the particle content of the minimal model by two vector-like pairs of
weak doublets (one pair of leptons and one pair of down-type quarks) and one
vector-like pair of neutrino singlets. Imposing collider and low-energy
constraints, sneutrinos and neutralinos both emerge as possible lightest
supersymmetric particles and thus dark matter candidates. We perform a complete
analysis of the dark sector and study the viability of these neutralino and
sneutrino dark matter options. We show that cosmological considerations (the
dark matter relic abundance and its direct and indirect detection signals)
restrict neutralino dark matter to exhibit similar properties as in the minimal
supersymmetric standard model, and impose the sneutrino dark matter candidate
to be singlet-like, rather than doublet-like. Allowing the mixing of the
fermionic component of the new supermultiplets with the Standard Model third
generation fermions, we moreover demonstrate the existence of collider signals
that are distinguishable from other, more minimal, supersymmetric scenarios by
virtue of an enhanced production of events enriched in tau leptons. We
furthermore show that this signature yields robust LHC signals, that could
potentially be differentiated from the background in future data.
| [
{
"created": "Tue, 16 Oct 2018 18:38:15 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Nov 2018 16:18:15 GMT",
"version": "v2"
}
] | 2018-12-06 | [
[
"Araz",
"Jack Y.",
""
],
[
"Banerjee",
"Shankha",
""
],
[
"Frank",
"Mariana",
""
],
[
"Fuks",
"Benjamin",
""
],
[
"Goudelis",
"Andreas",
""
]
] | Motivated by grand unification considerations, we analyze a simple extension of the minimal supersymmetric standard model with additional pairs of vector-like chiral supermultiplets. We focus on the so-called LND setup, which enlarges the particle content of the minimal model by two vector-like pairs of weak doublets (one pair of leptons and one pair of down-type quarks) and one vector-like pair of neutrino singlets. Imposing collider and low-energy constraints, sneutrinos and neutralinos both emerge as possible lightest supersymmetric particles and thus dark matter candidates. We perform a complete analysis of the dark sector and study the viability of these neutralino and sneutrino dark matter options. We show that cosmological considerations (the dark matter relic abundance and its direct and indirect detection signals) restrict neutralino dark matter to exhibit similar properties as in the minimal supersymmetric standard model, and impose the sneutrino dark matter candidate to be singlet-like, rather than doublet-like. Allowing the mixing of the fermionic component of the new supermultiplets with the Standard Model third generation fermions, we moreover demonstrate the existence of collider signals that are distinguishable from other, more minimal, supersymmetric scenarios by virtue of an enhanced production of events enriched in tau leptons. We furthermore show that this signature yields robust LHC signals, that could potentially be differentiated from the background in future data. |
hep-ph/9512385 | null | Dmitri Diakonov, Hilmar Forkel and Matthias Lutz | Dynamical Higgs Mechanism without Elementary Scalars: A Lesson from
Instantons | 13 pages (REVTEX), 4 postscript figures | Phys.Lett.B373:147-152,1996 | 10.1016/0370-2693(96)00143-8 | ECT*/Dec/95-003 | hep-ph | null | The generation of gauge--dependent fermion vacuum condensates in Yang--Mills
theory would dynamically break the gauge symmetry and thus provide an
alternative to the Higgs mechanism in unified theories. We explore a simple
example: instanton-induced quark pair (diquark) condensation in QCD with 2
flavors and $N_c$ colors. We do find diquark condensates in the vacuum, but
only for $N_c = 2$, where they are equivalent to the standard quark-antiquark
condensate. At $N_c \geq 3$ diquark condensates exist as meta--stable saddle
points of the instanton-induced effective QCD action and may strongly affect
the properties of matter under extreme conditions. The scalar diquark
excitation, which is a Goldstone boson at $N_c =2$, becomes unbound for $N_c
\geq 3$.
| [
{
"created": "Wed, 20 Dec 1995 23:09:00 GMT",
"version": "v1"
}
] | 2010-12-16 | [
[
"Diakonov",
"Dmitri",
""
],
[
"Forkel",
"Hilmar",
""
],
[
"Lutz",
"Matthias",
""
]
] | The generation of gauge--dependent fermion vacuum condensates in Yang--Mills theory would dynamically break the gauge symmetry and thus provide an alternative to the Higgs mechanism in unified theories. We explore a simple example: instanton-induced quark pair (diquark) condensation in QCD with 2 flavors and $N_c$ colors. We do find diquark condensates in the vacuum, but only for $N_c = 2$, where they are equivalent to the standard quark-antiquark condensate. At $N_c \geq 3$ diquark condensates exist as meta--stable saddle points of the instanton-induced effective QCD action and may strongly affect the properties of matter under extreme conditions. The scalar diquark excitation, which is a Goldstone boson at $N_c =2$, becomes unbound for $N_c \geq 3$. |
hep-ph/9710351 | Stephen Parke | Stephen Parke (Fermi National Accelerator Laboratory) | Top Quark, W-boson and Light Higgs | 6 pages, 12 figures, Latex, aip2col.sty, talk presented at Frontiers
in Contemporary Physics; ``Fundamental Particles and Interactions,'' May
11-16, 1997 at Vanderbilt University, Nashville TN | null | 10.1063/1.55090 | Fermilab-Conf-97/335-T | hep-ph | null | In this presentation I will concentrate on top quark physics, the W-boson
mass and the possibility of discovering a light Higgs boson via associated
production at the Fermilab Tevatron.
| [
{
"created": "Tue, 14 Oct 1997 18:17:20 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Parke",
"Stephen",
"",
"Fermi National Accelerator Laboratory"
]
] | In this presentation I will concentrate on top quark physics, the W-boson mass and the possibility of discovering a light Higgs boson via associated production at the Fermilab Tevatron. |
2106.11084 | Xing-Xing Dong | Xing-Xing Dong, Tai-Fu Feng, Hai-Bin Zhang, Shu-Min Zhao, Jin-Lei Yang | Gravitational waves from the phase transition in the B-LSSM | null | null | 10.1007/JHEP12(2021)052 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based on the gauge symmetry group
$SU(3)_C\otimes{SU(2)_L}\otimes{U(1)_Y}\otimes{U(1)_{B-L}}$, the minimal
supersymmetric extension of the SM with local B-L gauge symmetry(B-LSSM) has
been introduced. In this model, we study the Higgs masses with the one-loop
zero temperature effective potential corrections. Besides, the finite
temperature effective potentials connected with two $U(1)_{B-L}$ Higgs singlets
are deduced specifically. Then we can obtain the gravitational wave spectrums
generated from the strong first-order phase transition. In the B-LSSM, the
gravitational wave signals can be as strong as $h^2\Omega_{GW}\sim10^{-11}$,
which may be detectable in the future experiments.
| [
{
"created": "Mon, 21 Jun 2021 13:08:45 GMT",
"version": "v1"
}
] | 2022-01-05 | [
[
"Dong",
"Xing-Xing",
""
],
[
"Feng",
"Tai-Fu",
""
],
[
"Zhang",
"Hai-Bin",
""
],
[
"Zhao",
"Shu-Min",
""
],
[
"Yang",
"Jin-Lei",
""
]
] | Based on the gauge symmetry group $SU(3)_C\otimes{SU(2)_L}\otimes{U(1)_Y}\otimes{U(1)_{B-L}}$, the minimal supersymmetric extension of the SM with local B-L gauge symmetry(B-LSSM) has been introduced. In this model, we study the Higgs masses with the one-loop zero temperature effective potential corrections. Besides, the finite temperature effective potentials connected with two $U(1)_{B-L}$ Higgs singlets are deduced specifically. Then we can obtain the gravitational wave spectrums generated from the strong first-order phase transition. In the B-LSSM, the gravitational wave signals can be as strong as $h^2\Omega_{GW}\sim10^{-11}$, which may be detectable in the future experiments. |
1105.1330 | Christof Sch\"upbach | Christoph Greub, Tobias Hurth, Volker Pilipp, Christof Sch\"upbach,
Matthias Steinhauser | Complete next-to-leading order gluino contributions to b--> s gamma and
b--> s g | 38 pages, including c++ code | null | 10.1016/j.nuclphysb.2011.07.017 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the first complete order alpha_s corrections to the Wilson
coefficients (at the high scale) of the various versions of magnetic and
chromomagnetic operators which are induced by a squark-gluino exchange. For
this matching calculation, we work out the on-shell amplitudes b--> s gamma and
b --> s g, both in the full and in the effective theory up to order alpha_s^2.
The most difficult part of the calculation is the evaluation of the two-loop
diagrams in the full theory; these can be split into two classes: a) diagrams
with one gluino and a virtual gluon; b) diagrams with two gluinos or with one
gluino and a four-squark vertex. Accordingly, the Wilson coefficients can be
split into a part a) and a part b). While part b) of the Wilson coefficients is
presented in this paper for the first time, part a) was given in (Bobeth et
al.). We checked their results for the coefficients of the magnetic operators
and found perfect agreement. Moreover, we work out the renormalization
procedure in great detail. Our results for the complete next-to-leading order
Wilson coefficients are fully analytic, but far too long to be printed. We
therefore publish them in the form of a C++ program. They constitute a crucial
building block for the phenomenological next-to-leading logarithmic analysis of
the branching ratio Bbar --> X_s gamma in a supersymmetric model beyond minimal
flavor violation.
| [
{
"created": "Fri, 6 May 2011 17:05:05 GMT",
"version": "v1"
}
] | 2015-05-28 | [
[
"Greub",
"Christoph",
""
],
[
"Hurth",
"Tobias",
""
],
[
"Pilipp",
"Volker",
""
],
[
"Schüpbach",
"Christof",
""
],
[
"Steinhauser",
"Matthias",
""
]
] | We present the first complete order alpha_s corrections to the Wilson coefficients (at the high scale) of the various versions of magnetic and chromomagnetic operators which are induced by a squark-gluino exchange. For this matching calculation, we work out the on-shell amplitudes b--> s gamma and b --> s g, both in the full and in the effective theory up to order alpha_s^2. The most difficult part of the calculation is the evaluation of the two-loop diagrams in the full theory; these can be split into two classes: a) diagrams with one gluino and a virtual gluon; b) diagrams with two gluinos or with one gluino and a four-squark vertex. Accordingly, the Wilson coefficients can be split into a part a) and a part b). While part b) of the Wilson coefficients is presented in this paper for the first time, part a) was given in (Bobeth et al.). We checked their results for the coefficients of the magnetic operators and found perfect agreement. Moreover, we work out the renormalization procedure in great detail. Our results for the complete next-to-leading order Wilson coefficients are fully analytic, but far too long to be printed. We therefore publish them in the form of a C++ program. They constitute a crucial building block for the phenomenological next-to-leading logarithmic analysis of the branching ratio Bbar --> X_s gamma in a supersymmetric model beyond minimal flavor violation. |
hep-ph/0403264 | Toshifumi Yamashita | Naoyuki Haba and Toshifumi Yamashita | Vacuum structure in 5D SO(10) GUT on $S^1/Z_2$ | 9 pages | Phys.Lett.B597:166-172,2004 | 10.1016/j.physletb.2004.07.015 | KUNS-1904 | hep-ph | null | We study the vacuum structure in 5D SO(10) grand unified theory (GUT)
compactified on $S^1/Z_2$ orbifold, where SO(10) is broken into $SU(3)\times
SU(2)\times U(1)^2$ through the boundary conditions. Although a lot of people
extended to 6D to avoid massless colored particle, we can show they obtain
finite masses by the radiative corrections. In a supersymmetric case, the
fermionic partner of the zero-mode can also acquire non-vanishing mass through
the SUSY breaking effects, and the gauge coupling unification can be recovered
by use of brane localized kinetic terms.
| [
{
"created": "Thu, 25 Mar 2004 12:17:01 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Haba",
"Naoyuki",
""
],
[
"Yamashita",
"Toshifumi",
""
]
] | We study the vacuum structure in 5D SO(10) grand unified theory (GUT) compactified on $S^1/Z_2$ orbifold, where SO(10) is broken into $SU(3)\times SU(2)\times U(1)^2$ through the boundary conditions. Although a lot of people extended to 6D to avoid massless colored particle, we can show they obtain finite masses by the radiative corrections. In a supersymmetric case, the fermionic partner of the zero-mode can also acquire non-vanishing mass through the SUSY breaking effects, and the gauge coupling unification can be recovered by use of brane localized kinetic terms. |
1510.07436 | Boris Blok | B. Blok (Technion) and P. Gunnellini (DESY) | Dynamical approach to MPI in W+dijet and Z+dijet production within the
PYTHIA event generator | 24 pages 10 figures. arXiv admin note: text overlap with
arXiv:1503.08246 | null | 10.1140/epjc/s10052-016-4035-7 | DESY number PUBDB-2015-04334 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The new numerical approach that includes 1 to 2 mechanism is applied to
double parton scattering (DPS) in W+dijet and Z+dijet final state production in
proton-proton collisions at LHC. By using the underlying event (UE) simulation
from a pythia 8 tune extracted in hadronic events, we show that, like in the
case of a four-jet final state, the inclusion of 1 to 2 mechanism improves the
description of experimental data measured at 7 TeV. In addition, predictions
for proton-proton collisions at a center-of-mass energy of 14 TeV are shown for
DPS- and UE-sensitive observables.
| [
{
"created": "Mon, 26 Oct 2015 10:46:17 GMT",
"version": "v1"
}
] | 2016-05-04 | [
[
"Blok",
"B.",
"",
"Technion"
],
[
"Gunnellini",
"P.",
"",
"DESY"
]
] | The new numerical approach that includes 1 to 2 mechanism is applied to double parton scattering (DPS) in W+dijet and Z+dijet final state production in proton-proton collisions at LHC. By using the underlying event (UE) simulation from a pythia 8 tune extracted in hadronic events, we show that, like in the case of a four-jet final state, the inclusion of 1 to 2 mechanism improves the description of experimental data measured at 7 TeV. In addition, predictions for proton-proton collisions at a center-of-mass energy of 14 TeV are shown for DPS- and UE-sensitive observables. |
hep-ph/9402359 | Goran Senjanovic | Goran Senjanovi\'c | Neutrino Mass | LaTeX, 7 pages. To be published in the Proceedings of the European
Physical Society Meeting, HEP93, Marseille, July 1993. IC/94/33 | null | null | null | hep-ph | null | We review the issue of neutrino mass by concentrating on the minimal
extensions of the standard model. In particular, we emphasize the role that
gravitation may play in this regard and discuss the central aspects of the
see-saw mechanism of generating neutrino mass, including the possibility of the
see-saw scale being close to the eelectroweak scale.
| [
{
"created": "Sat, 26 Feb 1994 19:08:30 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Senjanović",
"Goran",
""
]
] | We review the issue of neutrino mass by concentrating on the minimal extensions of the standard model. In particular, we emphasize the role that gravitation may play in this regard and discuss the central aspects of the see-saw mechanism of generating neutrino mass, including the possibility of the see-saw scale being close to the eelectroweak scale. |
hep-ph/0212200 | Alexander Tarakanov | A.V. Tarakanov, A.V. Reichel, S.A. Smolyansky (1), S.M. Schmidt, D.V.
Vinnik (2) ((1) Physics Department, Saratov State University, (2) Institute
of Theoretical Physics, Tuebingen University) | Kinetics of Vacuum Pair Creation in Strong Electromagnetic Fields | 8 pages, 2 figures | null | 10.1142/9789812705129_0035 | null | hep-ph | null | We study particle - antiparticle pair production under action of a strong
time dependent space homogeneous electric field at the presence of a collinear
constant magnetic field. We derive the kinetic equation for a such field
configuration for fermions and bosons in the framework of the Schwinger
mechanism of vacuum tunneling. We show the enhancement of pair production for
fermions with the increasing of the magnetic field as in the case of the
constant electromagnetic field. We have constructed closed set of equations,
which can be applied to some actual problems with manifestation of strong
electromagnetic fields, e.g., it is essential in the framework of the Flux Tube
Model of Quark - Gluon Plasma generation; for describing some cosmological
objects and especially because of the planned experiments on creation of
subcritical fields in the X-Free Electron Laser pulses.
| [
{
"created": "Fri, 13 Dec 2002 21:42:40 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Dec 2002 12:02:02 GMT",
"version": "v2"
}
] | 2017-08-23 | [
[
"Tarakanov",
"A. V.",
""
],
[
"Reichel",
"A. V.",
""
],
[
"Smolyansky",
"S. A.",
""
],
[
"Schmidt",
"S. M.",
""
],
[
"Vinnik",
"D. V.",
""
]
] | We study particle - antiparticle pair production under action of a strong time dependent space homogeneous electric field at the presence of a collinear constant magnetic field. We derive the kinetic equation for a such field configuration for fermions and bosons in the framework of the Schwinger mechanism of vacuum tunneling. We show the enhancement of pair production for fermions with the increasing of the magnetic field as in the case of the constant electromagnetic field. We have constructed closed set of equations, which can be applied to some actual problems with manifestation of strong electromagnetic fields, e.g., it is essential in the framework of the Flux Tube Model of Quark - Gluon Plasma generation; for describing some cosmological objects and especially because of the planned experiments on creation of subcritical fields in the X-Free Electron Laser pulses. |
1010.4798 | Sannino Francesco | Matin Mojaza, Claudio Pica, Francesco Sannino | Hot Conformal Gauge Theories | RevTeX, 2-columns, 10 pages, 10 figures | Phys.Rev.D82:116009,2010 | 10.1103/PhysRevD.82.116009 | CP3-Origins-2010-45 | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the nonzero temperature free energy up to the order g^6 \ln(1/g)
in the coupling constant for vector like SU(N) gauge theories featuring matter
transforming according to different representations of the underlying gauge
group. The number of matter fields, i.e. flavors, is arranged in such a way
that the theory develops a perturbative stable infrared fixed point at zero
temperature. Due to large distance conformality we trade the coupling constant
with its fixed point value and define a reduced free energy which depends only
on the number of flavors, colors and matter representation.
We show that the reduced free energy changes sign, at the second, fifth and
sixth order in the coupling, when decreasing the number of flavors from the
upper end of the conformal window. If the change in sign is interpreted as
signal of an instability of the system then we infer a critical number of
flavors. Surprisingly this number, if computed to the order g^2, agrees with
previous predictions for the lower boundary of the conformal window for
nonsupersymmetric gauge theories. The higher order results tend to predict a
higher number of critical flavors. These are universal properties, i.e. they
are independent on the specific matter representation.
| [
{
"created": "Fri, 22 Oct 2010 20:00:04 GMT",
"version": "v1"
}
] | 2011-03-07 | [
[
"Mojaza",
"Matin",
""
],
[
"Pica",
"Claudio",
""
],
[
"Sannino",
"Francesco",
""
]
] | We compute the nonzero temperature free energy up to the order g^6 \ln(1/g) in the coupling constant for vector like SU(N) gauge theories featuring matter transforming according to different representations of the underlying gauge group. The number of matter fields, i.e. flavors, is arranged in such a way that the theory develops a perturbative stable infrared fixed point at zero temperature. Due to large distance conformality we trade the coupling constant with its fixed point value and define a reduced free energy which depends only on the number of flavors, colors and matter representation. We show that the reduced free energy changes sign, at the second, fifth and sixth order in the coupling, when decreasing the number of flavors from the upper end of the conformal window. If the change in sign is interpreted as signal of an instability of the system then we infer a critical number of flavors. Surprisingly this number, if computed to the order g^2, agrees with previous predictions for the lower boundary of the conformal window for nonsupersymmetric gauge theories. The higher order results tend to predict a higher number of critical flavors. These are universal properties, i.e. they are independent on the specific matter representation. |
hep-ph/9510286 | Toru Goto | Toru Goto (Tohoku Univ), Takeshi Nihei (ICRR) and Yasuhiro Okada (KEK) | $B^0$--$\overline{B}^0$ mixing and $\epsilon_K$ parameter in the minimal
supergravity model | LaTeX, 23 pages + 12 figures (not included). Figures are available
upon request or at
ftp://tuhep.phys.tohoku.ac.jp/preprints/kek-th-445-figures.tar.gz | Phys.Rev.D53:5233,1996; Erratum-ibid.D54:5904,1996;
Phys.Rev.D54:5904,1996 | 10.1103/PhysRevD.53.5233 10.1103/PhysRevD.54.5904 | KEK-TH-445, KEK preprint 95-125, ICRR-Report-341-95-7, TU-485 | hep-ph | null | \bb mixing and a CP violation parameter in \kk mixing $\epsilon_K$ are
studied in the minimal supergravity model. We solve the one-loop
renormalization group equations for the minimal supersymmetric standard model
(MSSM) parameters numerically in order to determine the masses and mixings of
the supersymmetric particles, while all off-diagonal (generation mixing)
elements and phases of Yukawa coupling matrices and those of squark mass
matrices are taken into account. Applying the radiative electroweak symmetry
breaking condition and phenomenological constraints including the recent
measurement of the \bsg inclusive branching ratio, we obtain the allowed
parameter region. We have found that the present constraints still allow a
parameter region where both \bb mass splitting $\Delta M_B$ and $\epsilon_K$
are $\sim 20$\% larger than the standard model values. By explicit numerical
calculations, we have also found that the complex phase of \bb mixing matrix
element in this model is almost the same as the standard model value in a good
accuracy in the whole allowed parameter region. It is shown that $\Delta M_B$
and $\epsilon_K$ can put useful constraints on the supersymmetry's parameter
space when the Cabibbo-Kobayashi-Maskawa matrix elements are determined through
the measurements of CP violations in $B$ decay with future $B$-factories.
| [
{
"created": "Fri, 13 Oct 1995 11:51:00 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Goto",
"Toru",
"",
"Tohoku Univ"
],
[
"Nihei",
"Takeshi",
"",
"ICRR"
],
[
"Okada",
"Yasuhiro",
"",
"KEK"
]
] | \bb mixing and a CP violation parameter in \kk mixing $\epsilon_K$ are studied in the minimal supergravity model. We solve the one-loop renormalization group equations for the minimal supersymmetric standard model (MSSM) parameters numerically in order to determine the masses and mixings of the supersymmetric particles, while all off-diagonal (generation mixing) elements and phases of Yukawa coupling matrices and those of squark mass matrices are taken into account. Applying the radiative electroweak symmetry breaking condition and phenomenological constraints including the recent measurement of the \bsg inclusive branching ratio, we obtain the allowed parameter region. We have found that the present constraints still allow a parameter region where both \bb mass splitting $\Delta M_B$ and $\epsilon_K$ are $\sim 20$\% larger than the standard model values. By explicit numerical calculations, we have also found that the complex phase of \bb mixing matrix element in this model is almost the same as the standard model value in a good accuracy in the whole allowed parameter region. It is shown that $\Delta M_B$ and $\epsilon_K$ can put useful constraints on the supersymmetry's parameter space when the Cabibbo-Kobayashi-Maskawa matrix elements are determined through the measurements of CP violations in $B$ decay with future $B$-factories. |
1906.10745 | Doojin Kim | Bhaskar Dutta, Doojin Kim, Shu Liao, Jong-Chul Park, Seodong Shin,
Louis E. Strigari | Dark matter signals from timing spectra at neutrino experiments | 8 pages, 7 figures, 1 table, to appear in PRL | Phys. Rev. Lett. 124, 121802 (2020) | 10.1103/PhysRevLett.124.121802 | MI-TH-1925 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a novel strategy to search for new physics in timing spectra,
envisioning the situation in which a new particle comes from the decay of its
heavier partner with a finite particle width. The timing distribution of events
induced by the dark matter particle scattering at the detector may populate in
a relatively narrow range, forming a "resonance-like" shape. Due to this
structural feature, the signal may be isolated from the backgrounds, in
particular when the backgrounds are uniformly distributed in energy and time.
For proof of the principle, we investigate the discovery potential for dark
matter from the decay of a dark photon in the COHERENT experiment, and show the
exciting prospects for exploring the associated parameter space with this
experiment. We analyze the existing CsI detector data with a timing cut and an
energy cut, and find, for the first time, an excess in the timing distribution
which can be explained by such dark matter. We compare the sensitivity to the
kinetic mixing parameter ($\epsilon$) for current and future COHERENT
experiments with the projected limits from LDMX and DUNE.
| [
{
"created": "Tue, 25 Jun 2019 19:52:58 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Jul 2019 03:10:53 GMT",
"version": "v2"
},
{
"created": "Sat, 29 Feb 2020 06:18:31 GMT",
"version": "v3"
}
] | 2020-04-01 | [
[
"Dutta",
"Bhaskar",
""
],
[
"Kim",
"Doojin",
""
],
[
"Liao",
"Shu",
""
],
[
"Park",
"Jong-Chul",
""
],
[
"Shin",
"Seodong",
""
],
[
"Strigari",
"Louis E.",
""
]
] | We propose a novel strategy to search for new physics in timing spectra, envisioning the situation in which a new particle comes from the decay of its heavier partner with a finite particle width. The timing distribution of events induced by the dark matter particle scattering at the detector may populate in a relatively narrow range, forming a "resonance-like" shape. Due to this structural feature, the signal may be isolated from the backgrounds, in particular when the backgrounds are uniformly distributed in energy and time. For proof of the principle, we investigate the discovery potential for dark matter from the decay of a dark photon in the COHERENT experiment, and show the exciting prospects for exploring the associated parameter space with this experiment. We analyze the existing CsI detector data with a timing cut and an energy cut, and find, for the first time, an excess in the timing distribution which can be explained by such dark matter. We compare the sensitivity to the kinetic mixing parameter ($\epsilon$) for current and future COHERENT experiments with the projected limits from LDMX and DUNE. |
hep-ph/9904430 | Gabriel Lopez Castro | G. Lopez Castro and G. Toledo Sanchez | Vector-meson magnetic dipole moment effects in radiative tau decays | Latex, 12 pages, 4 figures, submitted to PRD | Phys.Rev. D60 (1999) 053004 | 10.1103/PhysRevD.60.053004 | null | hep-ph | null | We study the possibility that the magnetic dipole moment of light charged
vector mesons could be measured from their effects in \tau^- -->
V^-\nu_{\tau}\gamma decays. We conclude that the energy spectrum and angular
distribution of photons emitted at small angles with respect to vector mesons
is sensitive the effects of the magnetic dipole moment. Model-dependent
contributions and photon radiation off other electromagnetic multipoles are
small in this region. We also compute the effects of the magnetic dipole moment
on the integrated rates and photon energy spectrum of these $\tau$ lepton
decays.
| [
{
"created": "Thu, 22 Apr 1999 16:51:53 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Castro",
"G. Lopez",
""
],
[
"Sanchez",
"G. Toledo",
""
]
] | We study the possibility that the magnetic dipole moment of light charged vector mesons could be measured from their effects in \tau^- --> V^-\nu_{\tau}\gamma decays. We conclude that the energy spectrum and angular distribution of photons emitted at small angles with respect to vector mesons is sensitive the effects of the magnetic dipole moment. Model-dependent contributions and photon radiation off other electromagnetic multipoles are small in this region. We also compute the effects of the magnetic dipole moment on the integrated rates and photon energy spectrum of these $\tau$ lepton decays. |
1407.0281 | Eleni Vryonidou | Benoit Hespel, David Lopez-Val, Eleni Vryonidou | Higgs pair production via gluon fusion in the Two-Higgs-Doublet Model | 39 pages, 10 figures, 11 tables, matching published version | null | 10.1007/JHEP09(2014)124 | MCnet-14-12,CP3-14-48 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the production of Higgs boson pairs via gluon fusion at the LHC in
the Two-Higgs-Doublet Model. We present predictions at NLO accuracy in QCD,
matched to parton showers through the MC@NLO method. A dedicated reweighting
technique is used to improve the NLO calculation upon the infinite top-mass
limit. We perform our calculation within the MadGraph5_aMC@NLO framework, along
with the 2HDM implementation based on the NLOCT package. The inclusion of the
NLO corrections leads to large K-factors and significantly reduced theoretical
uncertainties. We examine the seven 2HDM Higgs pair combinations using a number
of representative 2HDM scenarios. We show how the model-specific features
modify the Higgs pair total rates and distribution shapes, leading to trademark
signatures of an extended Higgs sector.
| [
{
"created": "Tue, 1 Jul 2014 15:31:17 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Sep 2014 15:39:21 GMT",
"version": "v2"
}
] | 2014-10-01 | [
[
"Hespel",
"Benoit",
""
],
[
"Lopez-Val",
"David",
""
],
[
"Vryonidou",
"Eleni",
""
]
] | We study the production of Higgs boson pairs via gluon fusion at the LHC in the Two-Higgs-Doublet Model. We present predictions at NLO accuracy in QCD, matched to parton showers through the MC@NLO method. A dedicated reweighting technique is used to improve the NLO calculation upon the infinite top-mass limit. We perform our calculation within the MadGraph5_aMC@NLO framework, along with the 2HDM implementation based on the NLOCT package. The inclusion of the NLO corrections leads to large K-factors and significantly reduced theoretical uncertainties. We examine the seven 2HDM Higgs pair combinations using a number of representative 2HDM scenarios. We show how the model-specific features modify the Higgs pair total rates and distribution shapes, leading to trademark signatures of an extended Higgs sector. |
hep-ph/9909557 | Kolya Nikolaev | N.N. Nikolaev (IKP, Forschungszentrum Juelich, Germany and L.D.Landau
Institute, Chernogolovka, Russia), J. Speth (IKP, Forschungszentrum Juelich,
Germany) and B.G. Zakharov (L.D.Landau Institute, Chernogolovka, Russia) | Nuclear-Medium Modification of the Rho(1S)- and Rhoprim(2S)-Mesons in
Coherent Photo- and Electroproduction: Coupled Channel Analysis | 18 pages, 9 figures | Phys.Atom.Nucl. 63 (2000) 1463-1476; Yad.Fiz. 63 (2000) 1463-1476 | 10.1134/1.1307468 | FZJ-IKP(Th)-1999-26 | hep-ph | null | We study medium modifications of the dilepton mass spectrum in coherent
photo- and electroproduction of the Rho(1S)- and Rhoprim(2S)-meson resonances
on nuclear targets. The analysis is performed within the coupled Rho,
Rhoprim... channel formalism in which nuclear modifications derive from the
off-diagonal rescatterings. We find that the effect of off-diagonal
rescatterings on the shape of the dilepton mass spectrum in the Rho(1S)-meson
mass region is only marginal but is very important in the Rhoprim mass region.
The main off-diagonal contribution in the Rhoprim mass region comes from the
sequential mechanism gamma* -> Rho -> Rhoprim(2S), which dominates the
Rhoprim(2S) production for heavy nuclei.
Our results show also that in the Rhoprim(2S) mass region there is a
considerable effect of the interference of the Breit-Wigner tail of
Rho(1S)-meson with the Rhoprim-meson.
| [
{
"created": "Wed, 29 Sep 1999 17:17:22 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Nikolaev",
"N. N.",
"",
"IKP, Forschungszentrum Juelich, Germany and L.D.Landau\n Institute, Chernogolovka, Russia"
],
[
"Speth",
"J.",
"",
"IKP, Forschungszentrum Juelich,\n Germany"
],
[
"Zakharov",
"B. G.",
"",
"L.D.Landau Institute, Chernogolovka, Russia"
]
] | We study medium modifications of the dilepton mass spectrum in coherent photo- and electroproduction of the Rho(1S)- and Rhoprim(2S)-meson resonances on nuclear targets. The analysis is performed within the coupled Rho, Rhoprim... channel formalism in which nuclear modifications derive from the off-diagonal rescatterings. We find that the effect of off-diagonal rescatterings on the shape of the dilepton mass spectrum in the Rho(1S)-meson mass region is only marginal but is very important in the Rhoprim mass region. The main off-diagonal contribution in the Rhoprim mass region comes from the sequential mechanism gamma* -> Rho -> Rhoprim(2S), which dominates the Rhoprim(2S) production for heavy nuclei. Our results show also that in the Rhoprim(2S) mass region there is a considerable effect of the interference of the Breit-Wigner tail of Rho(1S)-meson with the Rhoprim-meson. |
2210.08058 | Zarina Banoo Ms | Zarina Banoo and Ramni Gupta | Intermittency analysis of charged particles generated in
Xe-Xe~collisions at $\sqrt{s_{\rm{NN}}}$ = 5.44 TeV using the AMPT model | 4 pages, 5 figures, 51st International Symposium on Multiparticle
Dynamics (ISMD2022) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The multiplicity fluctuations are sensitive to QCD phase transition and to
the presence of critical point in QCD phase diagram. At critical point a system
undergoing phase transition is characterized by large fluctuations in the
observables which is an important tool to understand the dynamics of particle
production in heavy-ion interactions and phase changes. Multiplicity
fluctuations of produced particles is an important observable to characterize
the evolving system. Using scaling exponent obtained from the normalized
factorial moments of the number of charged hadrons in the two dimensional
($\eta,\phi$) phase space, one can learn about the dynamics of system created
in these collisions. Events generated using Xe-Xe collisions at
$\sqrt{s_{\rm{NN}}} = 5.44 $ TeV with string-melting (SM) version of the AMPT
model are analyzed and the scaling exponent $(\nu)$ for various $p_T$ intervals
is determined. It is observed that the calculated value of $\nu$ is larger than
the universal value 1.304, as is obtained from Ginzburg-Landau theory for
second order phase transition. Here we will also present the results of the
dependence of the scaling exponent on the transverse momentum bin width.
| [
{
"created": "Fri, 14 Oct 2022 18:49:27 GMT",
"version": "v1"
},
{
"created": "Wed, 23 Nov 2022 10:10:59 GMT",
"version": "v2"
}
] | 2022-11-24 | [
[
"Banoo",
"Zarina",
""
],
[
"Gupta",
"Ramni",
""
]
] | The multiplicity fluctuations are sensitive to QCD phase transition and to the presence of critical point in QCD phase diagram. At critical point a system undergoing phase transition is characterized by large fluctuations in the observables which is an important tool to understand the dynamics of particle production in heavy-ion interactions and phase changes. Multiplicity fluctuations of produced particles is an important observable to characterize the evolving system. Using scaling exponent obtained from the normalized factorial moments of the number of charged hadrons in the two dimensional ($\eta,\phi$) phase space, one can learn about the dynamics of system created in these collisions. Events generated using Xe-Xe collisions at $\sqrt{s_{\rm{NN}}} = 5.44 $ TeV with string-melting (SM) version of the AMPT model are analyzed and the scaling exponent $(\nu)$ for various $p_T$ intervals is determined. It is observed that the calculated value of $\nu$ is larger than the universal value 1.304, as is obtained from Ginzburg-Landau theory for second order phase transition. Here we will also present the results of the dependence of the scaling exponent on the transverse momentum bin width. |
2012.02616 | Felipe J. Llanes-Estrada | Juan Escudero-Pedrosa, Felipe J. Llanes-Estrada, Jos\'e Antonio Oller,
Alexandre Salas-Bern\'ardez | Assessment of systematic theory uncertainties in IAM unitarization | 5 page letter for the proceedings of QCD20, 23TH International
Conference in Quantum Chromodynamics (27-20 October 2020, Montpellier) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Effective Field Theories (EFTs) for Goldstone Boson scattering at a low order
allow the computation of near--threshold observables in terms of a few
coefficients arranged by a counting. As a matter of principle they should make
sense up to an energy scale $E\sim 4\pi F$ but the expansion in powers of
momentum violates exact elastic unitarity and renders the derivative expansion
unreliable at much lower energies. If new--physics deviations from the Standard
Model are found and encoded in low-energy coefficients, perhaps at the LHC, it
will be profitable to extend the reach of the EFT to regimes where partial
waves are saturating unitarity. The methods known in hadron physics as
"Unitarized Chiral Perturbation Theory" extend the EFT up to its nominal reach
or up to the first new physics resonance or structure (if found below that
energy reach) in the partial wave amplitude, but they usually have unknown
uncertainties. We recapitulate our analysis of the systematic theory
uncertainties of the well known Inverse Amplitude Method (IAM).
| [
{
"created": "Thu, 3 Dec 2020 16:14:55 GMT",
"version": "v1"
}
] | 2020-12-07 | [
[
"Escudero-Pedrosa",
"Juan",
""
],
[
"Llanes-Estrada",
"Felipe J.",
""
],
[
"Oller",
"José Antonio",
""
],
[
"Salas-Bernárdez",
"Alexandre",
""
]
] | Effective Field Theories (EFTs) for Goldstone Boson scattering at a low order allow the computation of near--threshold observables in terms of a few coefficients arranged by a counting. As a matter of principle they should make sense up to an energy scale $E\sim 4\pi F$ but the expansion in powers of momentum violates exact elastic unitarity and renders the derivative expansion unreliable at much lower energies. If new--physics deviations from the Standard Model are found and encoded in low-energy coefficients, perhaps at the LHC, it will be profitable to extend the reach of the EFT to regimes where partial waves are saturating unitarity. The methods known in hadron physics as "Unitarized Chiral Perturbation Theory" extend the EFT up to its nominal reach or up to the first new physics resonance or structure (if found below that energy reach) in the partial wave amplitude, but they usually have unknown uncertainties. We recapitulate our analysis of the systematic theory uncertainties of the well known Inverse Amplitude Method (IAM). |
hep-ph/9601314 | Konrad Martins | K. Martins | J/Psi and Psi' Suppression in Hadronic Matter | LaTeX, 6 pages including 2 EPS files, to be published in Prog. Part.
Nucl. Phys., martins@darss.mpg.uni-rostock.de | Prog.Part.Nucl.Phys. 36 (1996) 409-410 | 10.1016/0146-6410(96)00046-4 | MPG-VT-UR 77/95 | hep-ph | null | We present a microscopic calculation of the breakup cross sections of
$J/\psi$ and $\psi'$ on pions and nucleons as a function of the kinetic energy.
These cross sections are used for the investigation of the $J/\psi$ to
continuum and $\psi'/J/\psi$ ratios in ultrarelativistic heavy ion collisions.
The contribution of produced comoving pions to the $\psi'/J/\psi$ signal is
calculated. While this model can account for the data, the uncertainties in the
parameter values do not allow to exclude the possibility of additional sources
for charmonium absorption, like a resonance gas or the quark gluon plasma.
| [
{
"created": "Tue, 23 Jan 1996 13:09:47 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Jan 1996 10:10:51 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Martins",
"K.",
""
]
] | We present a microscopic calculation of the breakup cross sections of $J/\psi$ and $\psi'$ on pions and nucleons as a function of the kinetic energy. These cross sections are used for the investigation of the $J/\psi$ to continuum and $\psi'/J/\psi$ ratios in ultrarelativistic heavy ion collisions. The contribution of produced comoving pions to the $\psi'/J/\psi$ signal is calculated. While this model can account for the data, the uncertainties in the parameter values do not allow to exclude the possibility of additional sources for charmonium absorption, like a resonance gas or the quark gluon plasma. |
1003.5928 | Andre Yoon | Andre S. Yoon, Edward Wenger, Gunther Roland | Convoluting jet spectra with fragmentation functions: a cross-check of
the charged particle p_T spectrum | null | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the excellent agreement between next-to-leading-order pQCD
calculations and the inclusive jet spectra measured by CDF, we cross-check
PYTHIA fragmentation functions. The convolution of the measured jet spectra
with unmodified PYTHIA fragmentation functions results in reasonable agreement
with the PYTHIA charged particle spectrum over the entire p_T range of
interest, while there is a sizable disagreement with the measured charged
particle spectrum above p_T=30 GeV/c. In an attempt to understand the source of
this discrepancy, we introduce a number of increasingly different toy-model
fragmentation functions for the convolution. However, even the most extreme
fragmentation functions result in an underestimate of the high-p_T CDF
spectrum, which remains irreconcilable with the measured jet spectra.
| [
{
"created": "Tue, 30 Mar 2010 21:28:47 GMT",
"version": "v1"
}
] | 2015-03-13 | [
[
"Yoon",
"Andre S.",
""
],
[
"Wenger",
"Edward",
""
],
[
"Roland",
"Gunther",
""
]
] | Motivated by the excellent agreement between next-to-leading-order pQCD calculations and the inclusive jet spectra measured by CDF, we cross-check PYTHIA fragmentation functions. The convolution of the measured jet spectra with unmodified PYTHIA fragmentation functions results in reasonable agreement with the PYTHIA charged particle spectrum over the entire p_T range of interest, while there is a sizable disagreement with the measured charged particle spectrum above p_T=30 GeV/c. In an attempt to understand the source of this discrepancy, we introduce a number of increasingly different toy-model fragmentation functions for the convolution. However, even the most extreme fragmentation functions result in an underestimate of the high-p_T CDF spectrum, which remains irreconcilable with the measured jet spectra. |
hep-ph/0206017 | Nestor Armesto Perez | N. Armesto | A simple model for nuclear structure functions at small $x$ in the
dipole picture | LaTeX, 27 pages, 9 postscript figures included using epsfig; final
version: discussion on geometrical scaling clarified, comparison of gluon
densities with other approaches added, Fig. 8 redone, references added and
updated, some misprints corrected, results and conclusions unchanged | Eur.Phys.J.C26:35-43,2002 | 10.1007/s10052-002-1021-z | UCOFIS 1/02 | hep-ph nucl-th | null | A simple model for nuclear structure functions in the region of small x and
small and moderate $Q^2$, is presented. It is a parameter-free extension, in
the Glauber-Gribov approach to nuclear collisions, of a saturation model for
the nucleon. A reasonable agreement with experimental data on ratios of nuclear
structure functions is obtained. Nuclear effects in the
longitudinal-to-transverse cross section ratios are found to be small.
Predictions of the model for values of $x$ smaller than those available to
present experiments are given. The unintegrated gluon distribution and the
behaviour of the saturation scale which result from this model are shown and
discussed.
| [
{
"created": "Mon, 3 Jun 2002 16:50:00 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Jul 2002 10:08:58 GMT",
"version": "v2"
}
] | 2009-01-07 | [
[
"Armesto",
"N.",
""
]
] | A simple model for nuclear structure functions in the region of small x and small and moderate $Q^2$, is presented. It is a parameter-free extension, in the Glauber-Gribov approach to nuclear collisions, of a saturation model for the nucleon. A reasonable agreement with experimental data on ratios of nuclear structure functions is obtained. Nuclear effects in the longitudinal-to-transverse cross section ratios are found to be small. Predictions of the model for values of $x$ smaller than those available to present experiments are given. The unintegrated gluon distribution and the behaviour of the saturation scale which result from this model are shown and discussed. |
1104.5124 | Aleksi Vuorinen | Aleksi Vuorinen | The QCD Equation of State - From Nuclear Physics to Perturbation Theory | Invited talk at the workshop Excited QCD 2011, Lec Houches, Feb.
20-25, 2011. 6 pages, no figures | null | null | null | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk, we briefly review the current understanding of the behavior of
the QCD equation of state throughout the phase diagram. Special emphasis is
given to regions of phenomenological interest, and a number of important open
questions as well as directions of ongoing research are pointed out. These
include in particular the region of low temperatures and (moderately) high
densities, where at the moment we have extremely few first principles tools
available.
| [
{
"created": "Wed, 27 Apr 2011 12:33:52 GMT",
"version": "v1"
}
] | 2011-04-28 | [
[
"Vuorinen",
"Aleksi",
""
]
] | In this talk, we briefly review the current understanding of the behavior of the QCD equation of state throughout the phase diagram. Special emphasis is given to regions of phenomenological interest, and a number of important open questions as well as directions of ongoing research are pointed out. These include in particular the region of low temperatures and (moderately) high densities, where at the moment we have extremely few first principles tools available. |
hep-ph/9908519 | Clerbaux Barbara | Barbara Clerbaux | Elastic production of Vector Mesons at HERA: study of the scale of the
interaction and measurement of the helicity amplitudes | The note includes plots presented in the vector meson discussion
session of the Workshop of Low-x Physics (june 1999), Tel-Aviv, Israel. 12
pages, 7 figures, 1 table. New version with new model prediction | null | null | null | hep-ph | null | A compilation of H1 and ZEUS cross section measurements for elastic vector
meson production is presented as a function of the scale $K^2 = (Q^2+M_V^2)/4$,
where Q^2 is the exchanged photon virtuality and M_V is the mass of the vector
meson. The ratio of longitudinal to transverse cross sections R =
$\sigma_L/\sigma_T$ is presented as a function of Q^2/M^2_V. The cross sections
are separated in a transverse and a longitudinal component, and are presented
as a function of K^2. The intercept $\alpha(0)$ -- 1 governing the energy
dependence of the vector meson cross sections is compared with the $\lambda$
parameter measured in inclusive F_2 analysis. For $\rho$ meson production, the
helicity amplitude ratios $|T_{ij}|/|T_{00}|$, extracted from the H1 and ZEUS
measurements of the spin density matrix elements are presented as a function of
Q^2 and W and are compared to recent predictions.
| [
{
"created": "Tue, 31 Aug 1999 13:54:15 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Sep 1999 12:12:50 GMT",
"version": "v2"
}
] | 2009-09-25 | [
[
"Clerbaux",
"Barbara",
""
]
] | A compilation of H1 and ZEUS cross section measurements for elastic vector meson production is presented as a function of the scale $K^2 = (Q^2+M_V^2)/4$, where Q^2 is the exchanged photon virtuality and M_V is the mass of the vector meson. The ratio of longitudinal to transverse cross sections R = $\sigma_L/\sigma_T$ is presented as a function of Q^2/M^2_V. The cross sections are separated in a transverse and a longitudinal component, and are presented as a function of K^2. The intercept $\alpha(0)$ -- 1 governing the energy dependence of the vector meson cross sections is compared with the $\lambda$ parameter measured in inclusive F_2 analysis. For $\rho$ meson production, the helicity amplitude ratios $|T_{ij}|/|T_{00}|$, extracted from the H1 and ZEUS measurements of the spin density matrix elements are presented as a function of Q^2 and W and are compared to recent predictions. |
1806.07551 | Wally Melnitchouk | Y. Salamu, Chueng-Ryong Ji, W. Melnitchouk, A. W. Thomas, P. Wang | Parton distributions from nonlocal chiral SU(3) effective theory. I.
Splitting functions | 43 pages, 6 figures, version to appear in Phys. Rev. D | Phys. Rev. D 99, 014041 (2019) | 10.1103/PhysRevD.99.014041 | JLAB-THY-18-2746, ADP-18-17/T1065 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a new formulation of pseudoscalar meson loop corrections to
nucleon parton distributions within a nonlocal covariant chiral effective field
theory, including contributions from SU(3) octet and decuplet baryons. The
nonlocal Lagrangian, constrained by requirements of local gauge invariance and
Lorentz-invariant ultraviolet regularization, generates additional interactions
associated with gauge links. We use these to compute the full set of proton
$\to$ meson + baryon splitting functions, which in general contain on-shell and
off-shell contributions, in addition to $\delta$-function terms at zero
momentum, along with nonlocal contributions associated with the finite size of
the proton. We illustrate the shapes of the various local and nonlocal
functions numerically using a simple example of a dipole regulator.
| [
{
"created": "Wed, 20 Jun 2018 04:48:54 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Dec 2018 17:21:10 GMT",
"version": "v2"
}
] | 2019-02-06 | [
[
"Salamu",
"Y.",
""
],
[
"Ji",
"Chueng-Ryong",
""
],
[
"Melnitchouk",
"W.",
""
],
[
"Thomas",
"A. W.",
""
],
[
"Wang",
"P.",
""
]
] | We present a new formulation of pseudoscalar meson loop corrections to nucleon parton distributions within a nonlocal covariant chiral effective field theory, including contributions from SU(3) octet and decuplet baryons. The nonlocal Lagrangian, constrained by requirements of local gauge invariance and Lorentz-invariant ultraviolet regularization, generates additional interactions associated with gauge links. We use these to compute the full set of proton $\to$ meson + baryon splitting functions, which in general contain on-shell and off-shell contributions, in addition to $\delta$-function terms at zero momentum, along with nonlocal contributions associated with the finite size of the proton. We illustrate the shapes of the various local and nonlocal functions numerically using a simple example of a dipole regulator. |
0809.4062 | Massimo Passera | M. Passera, W.J. Marciano, A. Sirlin | The muon g-2 discrepancy: errors or new physics? | 4 pages. Invited talk at 16th International Conference on
Supersymmetry and the Unification of Fundamental Interactions (SUSY08), June
16-21 2008, Seoul, Korea | AIP Conf.Proc.1078:378-381,2009 | 10.1063/1.3051967 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | After a brief review of the muon g-2 status, we discuss hypothetical errors
in the Standard Model prediction that could explain the present discrepancy
with the experimental value. None of them looks likely. In particular, an
hypothetical increase of the hadroproduction cross section in low-energy e^+e^-
collisions could bridge the muon g-2 discrepancy, but is shown to be unlikely
in view of current experimental error estimates. If, nonetheless, this turns
out to be the explanation of the discrepancy, then the 95% CL upper bound on
the Higgs boson mass is reduced to about 130 GeV which, in conjunction with the
experimental 114.4 GeV 95% CL lower bound, leaves a narrow window for the mass
of this fundamental particle.
| [
{
"created": "Wed, 24 Sep 2008 01:37:04 GMT",
"version": "v1"
}
] | 2009-04-06 | [
[
"Passera",
"M.",
""
],
[
"Marciano",
"W. J.",
""
],
[
"Sirlin",
"A.",
""
]
] | After a brief review of the muon g-2 status, we discuss hypothetical errors in the Standard Model prediction that could explain the present discrepancy with the experimental value. None of them looks likely. In particular, an hypothetical increase of the hadroproduction cross section in low-energy e^+e^- collisions could bridge the muon g-2 discrepancy, but is shown to be unlikely in view of current experimental error estimates. If, nonetheless, this turns out to be the explanation of the discrepancy, then the 95% CL upper bound on the Higgs boson mass is reduced to about 130 GeV which, in conjunction with the experimental 114.4 GeV 95% CL lower bound, leaves a narrow window for the mass of this fundamental particle. |
2308.09737 | Peter Denton | Peter B. Denton and Julia Gehrlein | A Survey of Neutrino Flavor Models and the Neutrinoless Double Beta
Decay Funnel | 24 pages, 13 figures, 5 tables, Many models. Comments welcome! v2:
clarifying remarks, matches published version | Phys. Rev. D 109, 055028 (2024) | 10.1103/PhysRevD.109.055028 | CERN-TH-2023-160, CETUP-2023-006 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The neutrinoless double beta decay experimental effort continues to make
tremendous progress with hopes of covering the inverted neutrino mass hierarchy
in coming years and pushing from the quasi-degenerate hierarchy into the normal
hierarchy. As neutrino oscillation data is starting to suggest that the mass
ordering may be normal, we may well be faced with staring down the funnel of
death: a region of parameter space in the normal ordering where -- for a
particular cancellation among the absolute neutrino mass scale, the Majorana
phases, and the oscillation parameters -- the neutrinoless double beta decay
rate may be vanishingly small. To answer the question of whether this region of
parameter space is theoretically preferred, we survey five broad categories of
flavor model structures which make various different predictions for parameters
relevant for neutrinoless double beta decay to determine how likely it is that
the rate may be in this funnel region. We find that a non-negligible fraction
of predictions surveyed are at least partially in the funnel region. Our
results can guide model builders and experimentalists alike in focusing their
efforts on theoretically motivated regions of parameter space.
| [
{
"created": "Fri, 18 Aug 2023 18:00:00 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Mar 2024 23:17:25 GMT",
"version": "v2"
}
] | 2024-03-20 | [
[
"Denton",
"Peter B.",
""
],
[
"Gehrlein",
"Julia",
""
]
] | The neutrinoless double beta decay experimental effort continues to make tremendous progress with hopes of covering the inverted neutrino mass hierarchy in coming years and pushing from the quasi-degenerate hierarchy into the normal hierarchy. As neutrino oscillation data is starting to suggest that the mass ordering may be normal, we may well be faced with staring down the funnel of death: a region of parameter space in the normal ordering where -- for a particular cancellation among the absolute neutrino mass scale, the Majorana phases, and the oscillation parameters -- the neutrinoless double beta decay rate may be vanishingly small. To answer the question of whether this region of parameter space is theoretically preferred, we survey five broad categories of flavor model structures which make various different predictions for parameters relevant for neutrinoless double beta decay to determine how likely it is that the rate may be in this funnel region. We find that a non-negligible fraction of predictions surveyed are at least partially in the funnel region. Our results can guide model builders and experimentalists alike in focusing their efforts on theoretically motivated regions of parameter space. |
1502.04619 | Zhi-Gang Wang | Zhi-Gang Wang, Ye-Fan Tian | Tetraquark state candidates: $Y(4140)$, $Y(4274)$ and $X(4350)$ | 15 pages, 12 figures. arXiv admin note: substantial text overlap with
arXiv:1312.1537, arXiv:1403.0810; text overlap with arXiv:1502.00279 | Int.J.Mod.Phys.A30(2015)1550004 | 10.1142/S0217751X15500049 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article, we tentatively assign the $Y(4140)$, $Y(4274)$ and $X(4350)$
to be the scalar and tensor $cs\bar{c}\bar{s}$ tetraquark states, respectively,
and study them with the QCD sum rules. In the operator product expansion, we
take into account the vacuum condensates up to dimension-10. In calculations,
we use the formula $\mu=\sqrt{M^2_{X/Y/Z}-(2{\mathbb{M}}_c)^2}$ to determine
the energy scales of the QCD spectral densities. The numerical results favor
assigning the $Y(4140)$ to be the $J^{PC}=2^{++}$ diquark-antidiquark type
tetraquark state, and disfavor assigning the $Y(4274)$ and $X(4350)$ to be the
$0^{++}$ or $2^{++}$ tetraquark states.
| [
{
"created": "Fri, 13 Feb 2015 03:22:08 GMT",
"version": "v1"
}
] | 2015-02-17 | [
[
"Wang",
"Zhi-Gang",
""
],
[
"Tian",
"Ye-Fan",
""
]
] | In this article, we tentatively assign the $Y(4140)$, $Y(4274)$ and $X(4350)$ to be the scalar and tensor $cs\bar{c}\bar{s}$ tetraquark states, respectively, and study them with the QCD sum rules. In the operator product expansion, we take into account the vacuum condensates up to dimension-10. In calculations, we use the formula $\mu=\sqrt{M^2_{X/Y/Z}-(2{\mathbb{M}}_c)^2}$ to determine the energy scales of the QCD spectral densities. The numerical results favor assigning the $Y(4140)$ to be the $J^{PC}=2^{++}$ diquark-antidiquark type tetraquark state, and disfavor assigning the $Y(4274)$ and $X(4350)$ to be the $0^{++}$ or $2^{++}$ tetraquark states. |
hep-ph/0210347 | Andreas Nyffeler | Andreas Nyffeler (CPT Marseille) | Hadronic light-by-light scattering contribution to g_{mu}-2 | 5 pages including 2 figures, Latex, uses npb.sty; Talk presented at
the 6th International Symposium on Radiative Corrections (RADCOR 2002) and
the 6th Zeuthen Workshop on Elementary Particle Theory (Loops and Legs in
Quantum Field Theory), Kloster Banz, Germany, 8-13 September, 2002. To appear
in the proceedings | Nucl.Phys.Proc.Suppl. 116 (2003) 225-229 | 10.1016/S0920-5632(03)80174-3 | CPT-2002/P.4424 | hep-ph | null | We briefly review the current status of the hadronic light-by-light
scattering correction to the muon g-2. Then we present our semi-analytical
evaluation of the pion-pole contribution, using a description of the
pion-photon-photon transition form factor based on large-N_C and short-distance
properties of QCD. We derive a two-dimensional integral representation which
allows to separate the generic features from the model dependence, in order to
better control the latter. Finally, we sketch an effective field theory
approach to hadronic light-by-light scattering which yields the leading
logarithmic terms that are enhanced by a factor N_C. It also shows that the
modeling of hadronic light-by-light scattering by a constituent quark loop is
not consistent with QCD.
| [
{
"created": "Fri, 25 Oct 2002 09:40:59 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Nyffeler",
"Andreas",
"",
"CPT Marseille"
]
] | We briefly review the current status of the hadronic light-by-light scattering correction to the muon g-2. Then we present our semi-analytical evaluation of the pion-pole contribution, using a description of the pion-photon-photon transition form factor based on large-N_C and short-distance properties of QCD. We derive a two-dimensional integral representation which allows to separate the generic features from the model dependence, in order to better control the latter. Finally, we sketch an effective field theory approach to hadronic light-by-light scattering which yields the leading logarithmic terms that are enhanced by a factor N_C. It also shows that the modeling of hadronic light-by-light scattering by a constituent quark loop is not consistent with QCD. |
1009.5054 | Marko B. Popovic | Marko B. Popovic | Thanks to 2D and maybe even beyond: 115 GeV and 140 GeV almost Standard
Model Higgs without problems | 52 Pages, 11 Figures, 1 Table, 155 References, document created on
July 24, 2010, document submitted to the Physical Review D on July 25, 2010 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I address: (1) dynamical, likely local Higgs mass generation as resolution to
the 4D hierarchy and vacuum energy problems, (2) possibility that top
condensation may be explained by an interplay among the gluon and scalar
sectors, (3) the Higgs Mass Zero Crossing (HMZC) scale, most likely equal to
{\Lambda}_EWSB, in accord with standard cosmology or classic inflation, and (4)
two preferred Higgs regions centered at 116.5 GeV and 140.5 GeV with related
high energy models. I show that SM in 2D could simultaneously satisfy (a)
complete radiative generation of the Higgs mass via top loop and (b)
cancelation of the remaining leading order corrections to the scalar
propagator. The Higgs mass, m_H, parameterized with k=1 (2), in the leading
order is 113.0{\pm}1.0 GeV (143.4{\pm}1.3 GeV). I show that the SM top
condensation is consistent with the gluon and Higgs mediated top-anti top
interactions at tree level. I predict the QCD fine structure constant with the
mean value only 0.25% away from the world average value at {\sqrt}s=M_Z. The SM
driven theory at energies larger than the HMZC scale necessary includes
effective tachyonic Higgs (Popovic 2001). Here, I map the SM physical Higgs
mass to the low energy HMZC scale (0.8-1.8 TeV). I show that the very "long
lived" SM necessitates Higgs lighter than 146.5{\pm}2 GeV such that there is a
single HMZC scale at energies smaller than the Planck mass. I present candidate
m_H=138.1{\pm}1.8 GeV for the SM valid up to an energy scale, nearly equal
Planck mass, obtained from a conjecture which minimizes the parameters of the
Higgs potential. I introduce a class of models potentially exactly removing
tachyons. I analyze Composite Particles Models (CPM) (Popovic 2002) where top
quark is composite, composed of 3 fundamental fermions, and Higgs scalar is
composite, composed of 2 fundamental fermions, with m_H=2/3 m_t=115.4{\pm}0.9
GeV.
| [
{
"created": "Sun, 26 Sep 2010 03:14:54 GMT",
"version": "v1"
}
] | 2010-09-28 | [
[
"Popovic",
"Marko B.",
""
]
] | I address: (1) dynamical, likely local Higgs mass generation as resolution to the 4D hierarchy and vacuum energy problems, (2) possibility that top condensation may be explained by an interplay among the gluon and scalar sectors, (3) the Higgs Mass Zero Crossing (HMZC) scale, most likely equal to {\Lambda}_EWSB, in accord with standard cosmology or classic inflation, and (4) two preferred Higgs regions centered at 116.5 GeV and 140.5 GeV with related high energy models. I show that SM in 2D could simultaneously satisfy (a) complete radiative generation of the Higgs mass via top loop and (b) cancelation of the remaining leading order corrections to the scalar propagator. The Higgs mass, m_H, parameterized with k=1 (2), in the leading order is 113.0{\pm}1.0 GeV (143.4{\pm}1.3 GeV). I show that the SM top condensation is consistent with the gluon and Higgs mediated top-anti top interactions at tree level. I predict the QCD fine structure constant with the mean value only 0.25% away from the world average value at {\sqrt}s=M_Z. The SM driven theory at energies larger than the HMZC scale necessary includes effective tachyonic Higgs (Popovic 2001). Here, I map the SM physical Higgs mass to the low energy HMZC scale (0.8-1.8 TeV). I show that the very "long lived" SM necessitates Higgs lighter than 146.5{\pm}2 GeV such that there is a single HMZC scale at energies smaller than the Planck mass. I present candidate m_H=138.1{\pm}1.8 GeV for the SM valid up to an energy scale, nearly equal Planck mass, obtained from a conjecture which minimizes the parameters of the Higgs potential. I introduce a class of models potentially exactly removing tachyons. I analyze Composite Particles Models (CPM) (Popovic 2002) where top quark is composite, composed of 3 fundamental fermions, and Higgs scalar is composite, composed of 2 fundamental fermions, with m_H=2/3 m_t=115.4{\pm}0.9 GeV. |
hep-ph/9512268 | null | S. Urano, D. Ring, and R. Arnowitt | Gravitational GUT Breaking and the GUT-Planck Hierarchy | 11 pages, REVTeX, 1 figure included as an uuencoded Z-compressed
PostScript file. Our Web page at
http://physics.tamu.edu/~urano/research/gutplanck.html contains ready to
print PostScript version (with figures) as well as color version of plots | Phys.Rev.Lett.76:3663-3666,1996 | 10.1103/PhysRevLett.76.3663 | CTP-TAMU-48/95 | hep-ph | null | It is shown that non-renormalizable gravitational interactions in the Higgs
sector of supersymmetric grand unified theories (GUT's) can produce the
breaking of the unifying gauge group $G$ at the GUT scale $M_{\rm GUT} \sim
10^{16}$~GeV. Such a breaking offers an attractive alternative to the
traditional method where the superheavy GUT scale mass parameters are added ad
hoc into the theory. The mechanism also offers a natural explanation for the
closeness of the GUT breaking scale to the Planck scale. A study of the minimal
SU(5) model endowed with this mechanism is presented and shown to be
phenomenologically viable. A second model is examined where the Higgs doublets
are kept naturally light as Goldstone modes. This latter model also achieves
breaking of $G$ at $M_{\rm GUT}$ but cannot easily satisfy the current
experimental proton decay bound.
| [
{
"created": "Mon, 11 Dec 1995 07:37:26 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Urano",
"S.",
""
],
[
"Ring",
"D.",
""
],
[
"Arnowitt",
"R.",
""
]
] | It is shown that non-renormalizable gravitational interactions in the Higgs sector of supersymmetric grand unified theories (GUT's) can produce the breaking of the unifying gauge group $G$ at the GUT scale $M_{\rm GUT} \sim 10^{16}$~GeV. Such a breaking offers an attractive alternative to the traditional method where the superheavy GUT scale mass parameters are added ad hoc into the theory. The mechanism also offers a natural explanation for the closeness of the GUT breaking scale to the Planck scale. A study of the minimal SU(5) model endowed with this mechanism is presented and shown to be phenomenologically viable. A second model is examined where the Higgs doublets are kept naturally light as Goldstone modes. This latter model also achieves breaking of $G$ at $M_{\rm GUT}$ but cannot easily satisfy the current experimental proton decay bound. |
1811.10152 | Dao-Neng Gao | Dao-Neng Gao | Note on invisible decays of light mesons | 8 pages, 4 figures, minor changes and references added. To appear in
PRD | Phys. Rev. D 98, 113006 (2018) | 10.1103/PhysRevD.98.113006 | USTC-ICTS-18-19 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A search for the invisible decays of $\omega$ and $\phi$ mesons in $J/\psi\to
\omega (\phi)\eta$ transitions has been performed by the BESIII Collaboration
very recently. Inspired by this experimental study, we compute the lowest order
contribution to branching ratios of ${\cal B}(V\to\bar{\nu}\nu)$ with $V$
denoting $\rho,\;\omega,\;\phi$, as the standard model background to these
invisible decays. Our predictions are far below the upper bounds given by the
BESIII experiment. We also analyze the $J/\psi\to
\eta(\eta^\prime)\bar{\nu}\nu$ processes, and estimate their decay rates.
Furthermore, the invisible decays of light pseudoscalar mesons $P$ including
$\pi^0$, $\eta$, and $\eta^\prime$ are reexamined in the present note. It is
shown that, due to the helicity suppression of the two-neutrino final state,
the standard model contributions to $P\to{\rm invisible}$ decays are dominated
by $P\to\bar{\nu}\nu \bar{\nu}\nu$ processes.
| [
{
"created": "Mon, 26 Nov 2018 02:51:41 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Dec 2018 02:52:00 GMT",
"version": "v2"
}
] | 2018-12-26 | [
[
"Gao",
"Dao-Neng",
""
]
] | A search for the invisible decays of $\omega$ and $\phi$ mesons in $J/\psi\to \omega (\phi)\eta$ transitions has been performed by the BESIII Collaboration very recently. Inspired by this experimental study, we compute the lowest order contribution to branching ratios of ${\cal B}(V\to\bar{\nu}\nu)$ with $V$ denoting $\rho,\;\omega,\;\phi$, as the standard model background to these invisible decays. Our predictions are far below the upper bounds given by the BESIII experiment. We also analyze the $J/\psi\to \eta(\eta^\prime)\bar{\nu}\nu$ processes, and estimate their decay rates. Furthermore, the invisible decays of light pseudoscalar mesons $P$ including $\pi^0$, $\eta$, and $\eta^\prime$ are reexamined in the present note. It is shown that, due to the helicity suppression of the two-neutrino final state, the standard model contributions to $P\to{\rm invisible}$ decays are dominated by $P\to\bar{\nu}\nu \bar{\nu}\nu$ processes. |
1606.07075 | Raza Sufian | Raza Sabbir Sufian, Yi-Bo Yang, Andrei Alexandru, Terrence Draper,
Keh-Fei Liu, and Jian Liang | Strange Quark Magnetic Moment of the Nucleon at Physical Point | Published version in Physical Review Letters | Phys. Rev. Lett. 118, 042001 (2017) | 10.1103/PhysRevLett.118.042001 | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We report a lattice QCD calculation of the strange quark contribution to the
nucleon's magnetic moment and charge radius. This analysis presents the first
direct determination of strange electromagnetic form factors including at the
physical pion mass. We perform a model-independent extraction of the strange
magnetic moment and the strange charge radius from the electromagnetic form
factors in the momentum transfer range of $0.051 \,\text{GeV}^2 \lesssim Q^2
\lesssim 1.31 \,\text{GeV}^2 $. The finite lattice spacing and finite volume
corrections are included in a global fit with $24$ valence quark masses on four
lattices with different lattice spacings, different volumes, and four sea quark
masses including one at the physical pion mass. We obtain the strange magnetic
moment $G^s_M(0) = - 0.064(14)(09)\, \mu_N$. The four-sigma precision in
statistics is achieved partly due to low-mode averaging of the quark loop and
low-mode substitution to improve the statistics of the nucleon propagator. We
also obtain the strange charge radius $\langle r_s^2\rangle_E = -0.0043
(16)(14)\,$ $\text{fm}^2$.
| [
{
"created": "Wed, 22 Jun 2016 20:00:40 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Dec 2016 04:44:18 GMT",
"version": "v2"
},
{
"created": "Fri, 27 Jan 2017 17:32:54 GMT",
"version": "v3"
}
] | 2017-01-30 | [
[
"Sufian",
"Raza Sabbir",
""
],
[
"Yang",
"Yi-Bo",
""
],
[
"Alexandru",
"Andrei",
""
],
[
"Draper",
"Terrence",
""
],
[
"Liu",
"Keh-Fei",
""
],
[
"Liang",
"Jian",
""
]
] | We report a lattice QCD calculation of the strange quark contribution to the nucleon's magnetic moment and charge radius. This analysis presents the first direct determination of strange electromagnetic form factors including at the physical pion mass. We perform a model-independent extraction of the strange magnetic moment and the strange charge radius from the electromagnetic form factors in the momentum transfer range of $0.051 \,\text{GeV}^2 \lesssim Q^2 \lesssim 1.31 \,\text{GeV}^2 $. The finite lattice spacing and finite volume corrections are included in a global fit with $24$ valence quark masses on four lattices with different lattice spacings, different volumes, and four sea quark masses including one at the physical pion mass. We obtain the strange magnetic moment $G^s_M(0) = - 0.064(14)(09)\, \mu_N$. The four-sigma precision in statistics is achieved partly due to low-mode averaging of the quark loop and low-mode substitution to improve the statistics of the nucleon propagator. We also obtain the strange charge radius $\langle r_s^2\rangle_E = -0.0043 (16)(14)\,$ $\text{fm}^2$. |
1403.3857 | Abolfazl Mirjalili | M.M.Yazdanpanah, R.Mohammadi pour, A.Mirjalili | Target mass correction, based on the re-scaled parton densities | 8 pages, 4 figures. arXiv admin note: text overlap with
arXiv:1103.5710 by other authors | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Target mass correction (TMC) is being used to improve the theoretical results
for the nucleon structure functions. This improvement makes the fitting more
reliable with the available experimental data in lepton scattering off the
nucleon . The recent relations, using the Georgi and Politzer approach indicate
that employing TMC effect are cumbersome, long and contains complicated
integrals. Some of these integrals can not be solved exactly and people are
forced to use approximate methods which seems not to give sufficient and
precise results. On the other hand on analysing the TMC effect we encounter
with the threshold problem for nucleon structure which results to have the
structure function in a regions which are physically forbidden. Here we render
a new solution way, based on the re-scaled parton densities to resolve the
difficultly, relating to the TMC effect. Our solution way can be employed
directly and easily to the parton distribution rather than to the nucleon
structure function. There are different options to amend the parton densities.
What we call as third re-scaling is the best one. Using it we are able to
discard the threshold problem for the nucleon structure function without
resorting to apply some auxiliary mathematical tools like the step function
which is plausible by people . On this way we obtain a better agreement for the
nucleon structure function with the available experimental data in comparison
with the ordinary TMC results, based on Georgi and Politzer approach and some
other approaches.
| [
{
"created": "Sat, 15 Mar 2014 22:22:16 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Sep 2014 17:15:51 GMT",
"version": "v2"
}
] | 2014-09-02 | [
[
"Yazdanpanah",
"M. M.",
""
],
[
"pour",
"R. Mohammadi",
""
],
[
"Mirjalili",
"A.",
""
]
] | Target mass correction (TMC) is being used to improve the theoretical results for the nucleon structure functions. This improvement makes the fitting more reliable with the available experimental data in lepton scattering off the nucleon . The recent relations, using the Georgi and Politzer approach indicate that employing TMC effect are cumbersome, long and contains complicated integrals. Some of these integrals can not be solved exactly and people are forced to use approximate methods which seems not to give sufficient and precise results. On the other hand on analysing the TMC effect we encounter with the threshold problem for nucleon structure which results to have the structure function in a regions which are physically forbidden. Here we render a new solution way, based on the re-scaled parton densities to resolve the difficultly, relating to the TMC effect. Our solution way can be employed directly and easily to the parton distribution rather than to the nucleon structure function. There are different options to amend the parton densities. What we call as third re-scaling is the best one. Using it we are able to discard the threshold problem for the nucleon structure function without resorting to apply some auxiliary mathematical tools like the step function which is plausible by people . On this way we obtain a better agreement for the nucleon structure function with the available experimental data in comparison with the ordinary TMC results, based on Georgi and Politzer approach and some other approaches. |
0705.1896 | Keitaro Nagata | Keitaro Nagata, Atsushi Hosaka, V. Dmitra\v{s}inovi\' c | Chiral Properties of Baryon Interpolating Fields | 14 pages | Mod.Phys.Lett.A23:2381-2384,2008 | 10.1142/S0217732308029423 | null | hep-ph | null | We study the chiral transformation properties of all possible local
(non-derivative) interpolating field operators for baryons consisting of three
quarks with two flavors, assuming good isospin symmetry. We derive and use the
relations/identities among the baryon operators with identical quantum numbers
that follow from the combined colour, Dirac and isospin Fierz transformations.
These relations reduce the number of independent baryon operators with any
given spin and isospin. The Fierz identities also effectively restrict allowed
baryon chiral multiplets. It turns out that the chiral multiplets of the
baryons are equivalent to their Lorentz representation. For the two independent
nucleon operators the only permissible chiral multiplet is the fundamental one
$(\frac12,0)\oplus(0,\frac12)$. For the $\Delta$, admissible Lorentz
representations are $(1,\frac12)\oplus (\frac12,1)$ and
$(\frac32,0)\oplus(0,\frac32)$. In the case of the $(1,\frac12)\oplus
(\frac12,1)$ chiral multiplet the $I(J)=\frac32(\frac32)$ $\Delta$ field has
one $I(J)=\frac12(\frac32)$ chiral partner; otherwise it has none. We also
consider the Abelian ($U_A(1)$) chiral transformation properties of fields and
show that each baryon comes in two varieties: 1) with Abelian axial charge +3;
and 2) with Abelian axial charge -1. In case of the nucleon these are the two
Ioffe's fields; in case of the $\Delta$, the $(1,\frac12)\oplus (\frac12,1)$
multiplet has Abelian axial charge -1 and the $(\frac32,0)\oplus(0,\frac32)$
multiplet has Abelian axial charge +3.
| [
{
"created": "Mon, 14 May 2007 09:43:56 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Nagata",
"Keitaro",
""
],
[
"Hosaka",
"Atsushi",
""
],
[
"c",
"V. Dmitrašinovi\\'",
""
]
] | We study the chiral transformation properties of all possible local (non-derivative) interpolating field operators for baryons consisting of three quarks with two flavors, assuming good isospin symmetry. We derive and use the relations/identities among the baryon operators with identical quantum numbers that follow from the combined colour, Dirac and isospin Fierz transformations. These relations reduce the number of independent baryon operators with any given spin and isospin. The Fierz identities also effectively restrict allowed baryon chiral multiplets. It turns out that the chiral multiplets of the baryons are equivalent to their Lorentz representation. For the two independent nucleon operators the only permissible chiral multiplet is the fundamental one $(\frac12,0)\oplus(0,\frac12)$. For the $\Delta$, admissible Lorentz representations are $(1,\frac12)\oplus (\frac12,1)$ and $(\frac32,0)\oplus(0,\frac32)$. In the case of the $(1,\frac12)\oplus (\frac12,1)$ chiral multiplet the $I(J)=\frac32(\frac32)$ $\Delta$ field has one $I(J)=\frac12(\frac32)$ chiral partner; otherwise it has none. We also consider the Abelian ($U_A(1)$) chiral transformation properties of fields and show that each baryon comes in two varieties: 1) with Abelian axial charge +3; and 2) with Abelian axial charge -1. In case of the nucleon these are the two Ioffe's fields; in case of the $\Delta$, the $(1,\frac12)\oplus (\frac12,1)$ multiplet has Abelian axial charge -1 and the $(\frac32,0)\oplus(0,\frac32)$ multiplet has Abelian axial charge +3. |
1909.06656 | Leonid Glozman | L. Ya. Glozman | Reply to E. Shuryak's Comments on "Three regimes of QCD" | 4 pp | null | null | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In his recent Comments E. Shuryak reiterates old, unfortunately misleading
arguments in favor of deconfined Quark-Gluon Plasma (QGP) immediately above the
chiral restoration pseudocritical temperature. In a Comment devoted to our view
of QCD at high temperatures he does not address and even mention the essence of
our arguments. In recent years a new "hidden" symmetry in QCD was discovered.
It is a symmetry of the electric sector of QCD, that is higher than the chiral
symmetry of the QCD Lagrangian as the whole. This symmetry was clearly observed
above T_c in spatial correlators and very recently also in time correlators.
The latter correlators are directly related to observable spectral density.
Then in a model-independent way we conclude that degrees of freedom in QCD
above T_c, but below roughly 3T_c, are chirally symmetric quarks bound by the
chromoelectric field into color-singlet compounds without the chromomagnetic
effects. This regime of QCD has been referred to as a Stringy Fluid since such
objects are very reminiscent of strings.At higher temperatures there is a very
smooth transition to the partonic degrees of freedom, i.e. to the QGP regime.
Here we will address some of the points made by Shuryak.
| [
{
"created": "Sat, 14 Sep 2019 19:03:07 GMT",
"version": "v1"
}
] | 2019-09-17 | [
[
"Glozman",
"L. Ya.",
""
]
] | In his recent Comments E. Shuryak reiterates old, unfortunately misleading arguments in favor of deconfined Quark-Gluon Plasma (QGP) immediately above the chiral restoration pseudocritical temperature. In a Comment devoted to our view of QCD at high temperatures he does not address and even mention the essence of our arguments. In recent years a new "hidden" symmetry in QCD was discovered. It is a symmetry of the electric sector of QCD, that is higher than the chiral symmetry of the QCD Lagrangian as the whole. This symmetry was clearly observed above T_c in spatial correlators and very recently also in time correlators. The latter correlators are directly related to observable spectral density. Then in a model-independent way we conclude that degrees of freedom in QCD above T_c, but below roughly 3T_c, are chirally symmetric quarks bound by the chromoelectric field into color-singlet compounds without the chromomagnetic effects. This regime of QCD has been referred to as a Stringy Fluid since such objects are very reminiscent of strings.At higher temperatures there is a very smooth transition to the partonic degrees of freedom, i.e. to the QGP regime. Here we will address some of the points made by Shuryak. |
hep-ph/9610298 | Giovanni Amelino-Camelia | G. Amelino-Camelia | Simple GUTs | 15 pages, LaTex. Presented as plenary talk at QUARKS96, Yaroslavl,
Russia, May 5-11, 1996. To be published in the proceedings | null | null | OUTP-96-17P | hep-ph | null | Together with some positive features, such as the constrained hypercharge
assignments, grandunification models typically have some unwelcome aspects,
mostly associated with the rich and peculiarly selected matter content. I
discuss some ideas which might help to interpret (part of) this apparent
complexity arising in grandunification in terms of simple structures. I also
point out that the conventional criteria used to establish fine tuning in
grandunified models should be modified if these models are viewed as effective
low-energy descriptions of a more fundamental theory.
| [
{
"created": "Wed, 9 Oct 1996 13:24:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Amelino-Camelia",
"G.",
""
]
] | Together with some positive features, such as the constrained hypercharge assignments, grandunification models typically have some unwelcome aspects, mostly associated with the rich and peculiarly selected matter content. I discuss some ideas which might help to interpret (part of) this apparent complexity arising in grandunification in terms of simple structures. I also point out that the conventional criteria used to establish fine tuning in grandunified models should be modified if these models are viewed as effective low-energy descriptions of a more fundamental theory. |
2007.05858 | Chandan Mondal | Jiangshan Lan, Chandan Mondal | Pion-nucleus induced Drell-Yan cross section in models inspired by
light-front holography | 9 pages, 5 figures; to appear in Physics Letters B | Phys.Lett. B 807, 135613 (2020) | 10.1016/j.physletb.2020.135613 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We evaluate the cross section for the pion induced Drell-Yan process in two
different models of the pion light-front wave function, inspired by light-front
holographic approaches. We obtain the valence quark distribution functions in
those models, which after QCD evolution, are consistent with the experimental
data from the E-0615 experiment at Fermilab. Supplemented by the parton
distribution functions of the target nuclei, we obtain the cross section
consistent with the experimental data for the $\pi^-$ Nucleus $\rightarrow
{\mu^+\mu^-X}$ Drell-Yan process.
| [
{
"created": "Sat, 11 Jul 2020 21:27:15 GMT",
"version": "v1"
}
] | 2020-07-23 | [
[
"Lan",
"Jiangshan",
""
],
[
"Mondal",
"Chandan",
""
]
] | We evaluate the cross section for the pion induced Drell-Yan process in two different models of the pion light-front wave function, inspired by light-front holographic approaches. We obtain the valence quark distribution functions in those models, which after QCD evolution, are consistent with the experimental data from the E-0615 experiment at Fermilab. Supplemented by the parton distribution functions of the target nuclei, we obtain the cross section consistent with the experimental data for the $\pi^-$ Nucleus $\rightarrow {\mu^+\mu^-X}$ Drell-Yan process. |
0804.1231 | Dr. Rukmani Mohanta | B. Mawlong, R. Mohanta, A.K. Giri | Signature of new physics in B -> phi pi decay | 13 pages, 3 figures, version to appear in Phys. Lett. B | Phys.Lett.B668:116-120,2008 | 10.1016/j.physletb.2008.08.015 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the effect of an extra fourth quark generation and FCNC
mediated $Z$ and $Z'$ bosons on the rare decay mode $B^- \to \phi \pi^-$. In
the standard model, this mode receives only $b \to d$ penguin contributions and
therefore, highly suppressed with branching ratio $\sim 5 \times 10^{-9}$. This
in turn makes this mode a very sensitive probe for new physics. We find that
due to the above mentioned new physics contributions there is a significant
enhancement in its branching ratio. Furthermore, the direct CP violation
parameter which is identically zero in the SM is found to be quite significant.
If this mode will be observed in the upcoming LHCb experiment, it will not only
provide a clear signal of new physics but also can be used to constrain the new
physics parameter space.
| [
{
"created": "Tue, 8 Apr 2008 10:25:58 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Jun 2008 04:28:08 GMT",
"version": "v2"
},
{
"created": "Sun, 10 Aug 2008 06:57:00 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Mawlong",
"B.",
""
],
[
"Mohanta",
"R.",
""
],
[
"Giri",
"A. K.",
""
]
] | We investigate the effect of an extra fourth quark generation and FCNC mediated $Z$ and $Z'$ bosons on the rare decay mode $B^- \to \phi \pi^-$. In the standard model, this mode receives only $b \to d$ penguin contributions and therefore, highly suppressed with branching ratio $\sim 5 \times 10^{-9}$. This in turn makes this mode a very sensitive probe for new physics. We find that due to the above mentioned new physics contributions there is a significant enhancement in its branching ratio. Furthermore, the direct CP violation parameter which is identically zero in the SM is found to be quite significant. If this mode will be observed in the upcoming LHCb experiment, it will not only provide a clear signal of new physics but also can be used to constrain the new physics parameter space. |
2208.09811 | Sherry Raj | Sherry Raj and Tejinder P. Singh | A Lagrangian with $E_8\times E_8$ symmetry for the standard model and
pre-gravitation I. -- The bosonic Lagrangian, and a theoretical derivation of
the weak mixing angle | 16 pages, 3 figures | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Building on earlier work, we propose an elementary Lagrangian for the
unification of the standard model with pre-gravitation, assumed to have an
unbroken $E_8 \times E_8$ symmetry. The Lagrangian is patterned after the
kinetic energy of a free particle in Newtonian dynamics, generalising it to the
matrix-valued Lagrangian dynamics of a 2-brane on a split bioctonionic space.
Symmetry breaking gives rise to the standard model quarks and leptons of three
generations along with the known gauge interactions, and a novel right-handed
counterpart $SU(3)_{grav}\times SU(2)_R \times U(1)_g$ identified as
pre-gravitation. The goal of the present series of papers is to investigate if
this pre-quantum, pre-spacetime matrix-valued Lagrangian dynamics can lead to
the emergence of quantum field theory for the standard model, and classical
general relativity, possibly with some additional corrections. In this paper we
work out the bosonic part of the Lagrangian, and show how the anticipated 32
gauge bosons are recovered from the elementary Lagrangian. As an application,
we show that the asymptotic low energy weak mixing angle $\theta_W$ is given by
a solution of the equation $1 = (1/2)\sqrt{ \cos(\theta_{W}/2)}+ \sqrt
{\sin(\theta_{W}/2)}$, yielding $\sin^2\theta_W \approx 0.24996$.
| [
{
"created": "Sun, 21 Aug 2022 05:55:34 GMT",
"version": "v1"
}
] | 2022-08-24 | [
[
"Raj",
"Sherry",
""
],
[
"Singh",
"Tejinder P.",
""
]
] | Building on earlier work, we propose an elementary Lagrangian for the unification of the standard model with pre-gravitation, assumed to have an unbroken $E_8 \times E_8$ symmetry. The Lagrangian is patterned after the kinetic energy of a free particle in Newtonian dynamics, generalising it to the matrix-valued Lagrangian dynamics of a 2-brane on a split bioctonionic space. Symmetry breaking gives rise to the standard model quarks and leptons of three generations along with the known gauge interactions, and a novel right-handed counterpart $SU(3)_{grav}\times SU(2)_R \times U(1)_g$ identified as pre-gravitation. The goal of the present series of papers is to investigate if this pre-quantum, pre-spacetime matrix-valued Lagrangian dynamics can lead to the emergence of quantum field theory for the standard model, and classical general relativity, possibly with some additional corrections. In this paper we work out the bosonic part of the Lagrangian, and show how the anticipated 32 gauge bosons are recovered from the elementary Lagrangian. As an application, we show that the asymptotic low energy weak mixing angle $\theta_W$ is given by a solution of the equation $1 = (1/2)\sqrt{ \cos(\theta_{W}/2)}+ \sqrt {\sin(\theta_{W}/2)}$, yielding $\sin^2\theta_W \approx 0.24996$. |
hep-ph/0407266 | Jean-Philippe Lansberg | J.P. Lansberg, F. Bissey, J.R. Cudell, J. Cugnon and P. Stassart | A Simple Model for Generalised Parton Distributions of the Pion | Presented by J.P. Lansberg at 12th International Workshop on Deep
Inelastic Scattering (DIS 2004), 14-18 April 2004, Strbske Pleso, Slovakia, 5
pages, 4 figures, LaTeX, uses dis04.cls (included) | null | null | null | hep-ph | null | We present here an extension of our model for the pion, which we used
previously to calculate its diagonal structure function, to the off-forward
case. The imaginary part of the off-forward gamma^* pi -> gamma^* pi scattering
amplitude is evaluated in the chiral limit (m_pi=0) and related to the
twist-two and twist-three generalised parton distributions H, H3, H3tilde.
Non-perturbative effects, linked to the size of the pion and still preserving
gauge invariance, are included. Remarkable new relations between H, H3 and
H3tilde are obtained and discussed.
| [
{
"created": "Thu, 22 Jul 2004 13:13:19 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lansberg",
"J. P.",
""
],
[
"Bissey",
"F.",
""
],
[
"Cudell",
"J. R.",
""
],
[
"Cugnon",
"J.",
""
],
[
"Stassart",
"P.",
""
]
] | We present here an extension of our model for the pion, which we used previously to calculate its diagonal structure function, to the off-forward case. The imaginary part of the off-forward gamma^* pi -> gamma^* pi scattering amplitude is evaluated in the chiral limit (m_pi=0) and related to the twist-two and twist-three generalised parton distributions H, H3, H3tilde. Non-perturbative effects, linked to the size of the pion and still preserving gauge invariance, are included. Remarkable new relations between H, H3 and H3tilde are obtained and discussed. |
hep-ph/9708266 | null | L. Gamberg (Oklahoma U.), H. Reinhardt (Tuebingen U.) and H. Weigel
(Tuebingen U.) | Nucleon Structure Functions within a Chiral Soliton Model | 5 pages, 3 postscript figures, uses menu97.sty. Presented at the
MENU97 Conference, Vancouver, Canada, July 28th - Aug. 2nd, 1997; to appear
in proceedings | piN Newslett.13:342,1997 | null | OKHEP-97-03, UNITU-THEP-10/1997 | hep-ph | null | We study nucleon structure functions within the bosonized
Nambu--Jona--Lasinio model where the nucleon emerges as a chiral soliton. We
discuss the model predictions on the Gottfried sum rule for electron--nucleon
scattering. A comparison with a low--scale parametrization shows that the model
reproduces the gross features of the empirical structure functions. We also
compute the leading twist contributions of the polarized structure functions
$g_{1}(x)$ and $g_{2}(x)$ in this model. We compare the model predictions on
these structure functions with data from the E143 experiment by GLAP evolving
them appropriately.
| [
{
"created": "Thu, 7 Aug 1997 01:05:00 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Gamberg",
"L.",
"",
"Oklahoma U."
],
[
"Reinhardt",
"H.",
"",
"Tuebingen U."
],
[
"Weigel",
"H.",
"",
"Tuebingen U."
]
] | We study nucleon structure functions within the bosonized Nambu--Jona--Lasinio model where the nucleon emerges as a chiral soliton. We discuss the model predictions on the Gottfried sum rule for electron--nucleon scattering. A comparison with a low--scale parametrization shows that the model reproduces the gross features of the empirical structure functions. We also compute the leading twist contributions of the polarized structure functions $g_{1}(x)$ and $g_{2}(x)$ in this model. We compare the model predictions on these structure functions with data from the E143 experiment by GLAP evolving them appropriately. |
1904.04257 | Christopher T. Hill | Christopher T. Hill, Pedro A. N. Machado, Anders E. Thomsen, Jessica
Turner | Where are the Next Higgs Bosons? | 8 pages, 2 figures | Phys. Rev. D 100, 015051 (2019) | 10.1103/PhysRevD.100.015051 | FERMILAB-PUB-19-143-T, CP3-Origins-2019-15 DNRF90 | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | Simple symmetry arguments applied to the third generation lead to a
prediction: there exist new sequential Higgs doublets with masses of order
$\lesssim 5 $ TeV, with approximately universal Higgs-Yukawa coupling
constants, $g\sim 1$. This is calibrated by the known Higgs boson mass, the top
quark Higgs-Yukawa coupling, and the $b$-quark mass. A new massive
weak-isodoublet, $H_b$, coupled to the $b$-quark with $g\sim 1$ is predicted,
and may be accessible to the LHC at $13$ TeV, and definitively at the energy
upgraded LHC of $26$ TeV. The extension to leptons generates a new $H_\tau$ and
a possible $H_{\nu_\tau}$ doublet. The accessibility of the latter depends upon
whether the mass of the $\tau$-neutrino is Dirac or Majorana.
| [
{
"created": "Mon, 8 Apr 2019 18:00:00 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Apr 2019 15:53:17 GMT",
"version": "v2"
}
] | 2019-08-07 | [
[
"Hill",
"Christopher T.",
""
],
[
"Machado",
"Pedro A. N.",
""
],
[
"Thomsen",
"Anders E.",
""
],
[
"Turner",
"Jessica",
""
]
] | Simple symmetry arguments applied to the third generation lead to a prediction: there exist new sequential Higgs doublets with masses of order $\lesssim 5 $ TeV, with approximately universal Higgs-Yukawa coupling constants, $g\sim 1$. This is calibrated by the known Higgs boson mass, the top quark Higgs-Yukawa coupling, and the $b$-quark mass. A new massive weak-isodoublet, $H_b$, coupled to the $b$-quark with $g\sim 1$ is predicted, and may be accessible to the LHC at $13$ TeV, and definitively at the energy upgraded LHC of $26$ TeV. The extension to leptons generates a new $H_\tau$ and a possible $H_{\nu_\tau}$ doublet. The accessibility of the latter depends upon whether the mass of the $\tau$-neutrino is Dirac or Majorana. |
2209.13469 | Daniele Barducci | Daniele Barducci, Enrico Bertuzzo, Marco Taoso, Claudio Toni | Probing right-handed neutrinos dipole operators | 24 pages, 3 figures, matches published version | null | 10.1007/JHEP03(2023)239 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the minimal see-saw extension of the Standard Model with two
right-handed singlet fermions $N_{1,2}$ with mass at the GeV scale, augmented
by an effective dipole operator between the sterile states. We firstly review
current bounds on this effective interaction from fixed-target and collider
experiments as well as from astrophysical and cosmological observations. We
then highlight the prospects for testing the decay $N_2 \to N_1 \gamma$ induced
by the dipole at future facilities targeting long lived particles such as
ANUBIS, CODEX-b, FACET, FASER 2, MAPP and SHiP.
| [
{
"created": "Tue, 27 Sep 2022 15:37:58 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Apr 2023 10:06:50 GMT",
"version": "v2"
}
] | 2023-04-19 | [
[
"Barducci",
"Daniele",
""
],
[
"Bertuzzo",
"Enrico",
""
],
[
"Taoso",
"Marco",
""
],
[
"Toni",
"Claudio",
""
]
] | We consider the minimal see-saw extension of the Standard Model with two right-handed singlet fermions $N_{1,2}$ with mass at the GeV scale, augmented by an effective dipole operator between the sterile states. We firstly review current bounds on this effective interaction from fixed-target and collider experiments as well as from astrophysical and cosmological observations. We then highlight the prospects for testing the decay $N_2 \to N_1 \gamma$ induced by the dipole at future facilities targeting long lived particles such as ANUBIS, CODEX-b, FACET, FASER 2, MAPP and SHiP. |
hep-ph/9509207 | Piotr Chankowski | P.H. Chankowski, S. Pokorski | Up--dating for the paper ``The mass of the Higgs boson in the Standard
Model from precision tests'' (MPI--Ph/95--39, hep-ph/9505308) | 6 pages, LaTeX; 3 postscript figures in a separate uuencoded
Z-compressed file | null | null | null | hep-ph | null | The bounds on the Higgs mass in the Standard Model are re-analyzed using the
precision electroweak data presented at the International Europhysics
Conference on High Energy Physics, Brussels, 27 July -- 2 August, 1995
| [
{
"created": "Fri, 1 Sep 1995 13:53:51 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Chankowski",
"P. H.",
""
],
[
"Pokorski",
"S.",
""
]
] | The bounds on the Higgs mass in the Standard Model are re-analyzed using the precision electroweak data presented at the International Europhysics Conference on High Energy Physics, Brussels, 27 July -- 2 August, 1995 |
2007.08153 | Takaaki Nomura | P. Ko, Takaaki Nomura, Hiroshi Okada | Dark matter physics in dark $SU(2)$ gauge symmetry with non-Abelian
kinetic mixing | 20 pages, 5 figures | Phys. Rev. D 103, 095011 (2021) | 10.1103/PhysRevD.103.095011 | KIAS-P20036, APCTP Pre2020-010 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate a model of dark sector based on non-Abelian $SU(2)_D$ gauge
symmetry. This dark gauge symmetry is broken into discrete $Z_2$ via vacuum
expectation values of two real triplet scalars, and an $SU(2)_D$ doublet Dirac
fermion becomes $Z_2-$odd particles whose lighter component makes stable dark
matter candidate. The standard model and dark sector can be connected via the
scalar mixing and the gauge kinetic mixing generated by higher dimensional
operators. We then discuss relic density of dark matter and implications to
collider physics in the model. The most unique signatures of this model at the
LHC would be the dark scalar ($\Phi_1^{(')}$) productions where it subsequently
decays into : (1) a fermionic dark matter ($\chi_l$) and a heavy dark fermion
($\chi_h$) pair, $\Phi_1^{(')} \to \bar \chi_l \chi_h(\bar \chi_h \chi_l) $,
followed by $\chi_h$ decays into $\chi_l$ and non-Abelian dark gauge bosons
($X_i$'s) which decays into SM fermion pair $\bar f_{SM} f_{SM}$ resulting in
the reaction $p p \rightarrow \Phi_1^{(')} \rightarrow \bar \chi_h \chi_l (\bar
\chi_l \chi_h) \to f_{SM} \bar f_{SM} \chi_l \bar \chi_l $, (2) a pair of
$X_i$'s followed by $X_i$ decays into a DM pair or the SM fermions resulting in
the reaction, $p p \rightarrow \Phi_1^{(')} \rightarrow X_i X_i \rightarrow
\bar \chi_l \chi_l f_{SM} \bar f_{SM}$ or even number of $f_{SM} \bar{f}_{SM}$
pairs.
| [
{
"created": "Thu, 16 Jul 2020 07:24:18 GMT",
"version": "v1"
}
] | 2021-05-26 | [
[
"Ko",
"P.",
""
],
[
"Nomura",
"Takaaki",
""
],
[
"Okada",
"Hiroshi",
""
]
] | We investigate a model of dark sector based on non-Abelian $SU(2)_D$ gauge symmetry. This dark gauge symmetry is broken into discrete $Z_2$ via vacuum expectation values of two real triplet scalars, and an $SU(2)_D$ doublet Dirac fermion becomes $Z_2-$odd particles whose lighter component makes stable dark matter candidate. The standard model and dark sector can be connected via the scalar mixing and the gauge kinetic mixing generated by higher dimensional operators. We then discuss relic density of dark matter and implications to collider physics in the model. The most unique signatures of this model at the LHC would be the dark scalar ($\Phi_1^{(')}$) productions where it subsequently decays into : (1) a fermionic dark matter ($\chi_l$) and a heavy dark fermion ($\chi_h$) pair, $\Phi_1^{(')} \to \bar \chi_l \chi_h(\bar \chi_h \chi_l) $, followed by $\chi_h$ decays into $\chi_l$ and non-Abelian dark gauge bosons ($X_i$'s) which decays into SM fermion pair $\bar f_{SM} f_{SM}$ resulting in the reaction $p p \rightarrow \Phi_1^{(')} \rightarrow \bar \chi_h \chi_l (\bar \chi_l \chi_h) \to f_{SM} \bar f_{SM} \chi_l \bar \chi_l $, (2) a pair of $X_i$'s followed by $X_i$ decays into a DM pair or the SM fermions resulting in the reaction, $p p \rightarrow \Phi_1^{(')} \rightarrow X_i X_i \rightarrow \bar \chi_l \chi_l f_{SM} \bar f_{SM}$ or even number of $f_{SM} \bar{f}_{SM}$ pairs. |
2101.07302 | Fernando Navarra | C. Le Roux, F. S. Navarra and L. M. Abreu | Understanding the $K^*/K$ ratio in heavy ion collisions | 9 pages, 5 figures | null | 10.1016/j.physletb.2021.136284 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We study the $K^*$ meson dissociation in heavy ion collisions during the
hadron gas phase. We use the production and absorption cross sections of the
$K^*$ and $K$ mesons in a hadron gas, which were calculated in a previous work.
We compute the time evolution of the $K^*$ abundance and the $K^* /K$ ratio
during the hadron gas phase. Assuming a Bjorken type cooling and using an
empirical relation between the freeze-out temperature and the central
multiplicity density, we are able to write $K^* /K$ as a function of ($ dN /d
\eta (\eta =0)$). The obtained function is in very good agreement with recent
experimental data.
| [
{
"created": "Mon, 18 Jan 2021 19:45:34 GMT",
"version": "v1"
}
] | 2021-04-28 | [
[
"Roux",
"C. Le",
""
],
[
"Navarra",
"F. S.",
""
],
[
"Abreu",
"L. M.",
""
]
] | We study the $K^*$ meson dissociation in heavy ion collisions during the hadron gas phase. We use the production and absorption cross sections of the $K^*$ and $K$ mesons in a hadron gas, which were calculated in a previous work. We compute the time evolution of the $K^*$ abundance and the $K^* /K$ ratio during the hadron gas phase. Assuming a Bjorken type cooling and using an empirical relation between the freeze-out temperature and the central multiplicity density, we are able to write $K^* /K$ as a function of ($ dN /d \eta (\eta =0)$). The obtained function is in very good agreement with recent experimental data. |
hep-ph/9610402 | Hans Werner Hammer | M.J. Musolf (U. of Washington, Seattle), H.-W. Hammer (U. of
Washington & Mainz U.) and D. Drechsel (Mainz U.) | Nucleon Strangeness and Unitarity | Revtex, 35 pages, 11 Postscript figures, uses epsf.sty, rotate.sty | Phys.Rev.D55:2741,1997; Erratum-ibid.D62:079901,2000;
Phys.Rev.D62:079901,2000 | 10.1103/PhysRevD.55.2741 10.1103/PhysRevD.62.079901 | INT \#DOE/ER/40561-291-INT96-00-149 & MKPH-T-96-25 | hep-ph nucl-th | null | The strange-quark vector current form factors of the nucleon are analyzed
within the framework of dispersion relations. Particular attention is paid to
contributions made by $K\bar{K}$ intermediate states to the form factor
spectral functions. It is shown that, when the $K\bar{K}\to N\bar{N}$ amplitude
is evaluated in the Born approximation, the $K\bar{K}$ contributions are
identical to those arising from a one-loop calculation and entail a serious
violation of unitarity. The mean square strangeness radius and magnetic moment
are evaluated by imposing unitarity bounds on the kaon-nucleon partial wave
amplitudes. The impact of including the kaon's form factor in the dispersion
integrals is also evaluated.
| [
{
"created": "Fri, 18 Oct 1996 00:39:55 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Musolf",
"M. J.",
"",
"U. of Washington, Seattle"
],
[
"Hammer",
"H. -W.",
"",
"U. of\n Washington & Mainz U."
],
[
"Drechsel",
"D.",
"",
"Mainz U."
]
] | The strange-quark vector current form factors of the nucleon are analyzed within the framework of dispersion relations. Particular attention is paid to contributions made by $K\bar{K}$ intermediate states to the form factor spectral functions. It is shown that, when the $K\bar{K}\to N\bar{N}$ amplitude is evaluated in the Born approximation, the $K\bar{K}$ contributions are identical to those arising from a one-loop calculation and entail a serious violation of unitarity. The mean square strangeness radius and magnetic moment are evaluated by imposing unitarity bounds on the kaon-nucleon partial wave amplitudes. The impact of including the kaon's form factor in the dispersion integrals is also evaluated. |
hep-ph/9506338 | null | M.G.Ryskin, Yu.M.Shabelski and A.G.Shuvaev (Petersburg Nuclear Physics
Inst.) | Heavy Quark Production in Parton Model and in QCD | 12 pages, LaTeX, 10 uuencoded-compressed-tar figs | Z.Phys.C69:269-276,1996; Yad.Fiz.59:521-528,1996 | 10.1007/s002880050027 | US-FT/11-95 | hep-ph | null | The cross sections of heavy quark production in $pp$ collision and for their
photo- and electroproduction are calculated in the framework of QCD. The
virtual nature of the interacting gluons as well as their transverse motion and
different polarizations are taken into account. The obtained cross sections
exhibit more rapid growth with the initial energy than the parton model
predictions and the $p_T$ distributions of produced heavy quarks are more
smooth.
| [
{
"created": "Thu, 15 Jun 1995 11:07:08 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Jun 1995 03:31:18 GMT",
"version": "v2"
}
] | 2011-01-25 | [
[
"Ryskin",
"M. G.",
"",
"Petersburg Nuclear Physics\n Inst."
],
[
"Shabelski",
"Yu. M.",
"",
"Petersburg Nuclear Physics\n Inst."
],
[
"Shuvaev",
"A. G.",
"",
"Petersburg Nuclear Physics\n Inst."
]
] | The cross sections of heavy quark production in $pp$ collision and for their photo- and electroproduction are calculated in the framework of QCD. The virtual nature of the interacting gluons as well as their transverse motion and different polarizations are taken into account. The obtained cross sections exhibit more rapid growth with the initial energy than the parton model predictions and the $p_T$ distributions of produced heavy quarks are more smooth. |
2301.08626 | Jaakko Annala | Jaakko Annala and Kari Rummukainen | Electroweak Sphaleron in a Magnetic field | 15 pages, 16 figures, corrected typos, published version | Phys. Rev. D 107, 073006, 24 April 2023 | 10.1103/PhysRevD.107.073006 | null | hep-ph astro-ph.CO hep-lat | http://creativecommons.org/licenses/by/4.0/ | Using lattice simulations we calculate the rate of baryon number violating
processes, the sphaleron rate, in the Standard Model with an external
(hyper)magnetic field for temperatures across the electroweak cross-over,
focusing on the broken phase. Additionally, we compute the Higgs expectation
value and the pseudocritical temperature. The electroweak cross-over shifts to
lower temperatures with increasing external magnetic field, bringing the onset
of the suppression of the baryon number violation with it. When the
hypermagnetic field reaches the magitude $B_Y \approx 2 T^2$ the cross-over
temperature is reduced from $160$ GeV to $145$ GeV. In the broken phase for
small magnetic fields the rate behaves quadratically as a function of the
magnetic flux. For stronger magnetic fields the rate reaches a linear regime
which lasts until the field gets strong enough to restore the electroweak
symmetry where the symmetric phase rate is reached.
| [
{
"created": "Fri, 20 Jan 2023 15:18:12 GMT",
"version": "v1"
},
{
"created": "Mon, 23 Jan 2023 11:57:19 GMT",
"version": "v2"
},
{
"created": "Tue, 25 Apr 2023 17:50:00 GMT",
"version": "v3"
}
] | 2023-04-26 | [
[
"Annala",
"Jaakko",
""
],
[
"Rummukainen",
"Kari",
""
]
] | Using lattice simulations we calculate the rate of baryon number violating processes, the sphaleron rate, in the Standard Model with an external (hyper)magnetic field for temperatures across the electroweak cross-over, focusing on the broken phase. Additionally, we compute the Higgs expectation value and the pseudocritical temperature. The electroweak cross-over shifts to lower temperatures with increasing external magnetic field, bringing the onset of the suppression of the baryon number violation with it. When the hypermagnetic field reaches the magitude $B_Y \approx 2 T^2$ the cross-over temperature is reduced from $160$ GeV to $145$ GeV. In the broken phase for small magnetic fields the rate behaves quadratically as a function of the magnetic flux. For stronger magnetic fields the rate reaches a linear regime which lasts until the field gets strong enough to restore the electroweak symmetry where the symmetric phase rate is reached. |
hep-ph/0104197 | Loyal Durand | Loyal Durand, Phuoc Ha, and Gregory Jaczko | Effective field theory and the quark model, II. Structure of loop
corrections | 29 pages, 13 eps figures, uses epsf, revtex | Phys.Rev.D65:034019,2002; Erratum-ibid.D65:099904,2002 | 10.1103/PhysRevD.65.034019 10.1103/PhysRevD.65.099904 | null | hep-ph | null | We analyze the structure of meson loop corrections to the O($m_s$)
expressions for the baryon masses and magnetic moments in heavy-baryon chiral
perturbation theory (HBChPT), and show in detail how the bulk of the
corrections are absorbed into redefinitions of the unknown parameters of the
O($m_s$) chiral expansion. To effect this analysis, we use the
three-flavor-index representation of the effective baryon fields and HBChPT
developed in a preceding paper, and a decomposition of the corrections in terms
of effective one-, two-, and three-quark operators. The results show why the
loop corrections have so little effect on fits to the masses and moments, and
do not seriously disrupt the Gell-Mann--Okubo relations for the masses and the
Okubo relation for the moments even though individual loops can be quite large.
We also examine the momentum structure of the residual loop corrections, and
comment on limits on their validity in HBChPT. The structural analysis can be
generalized straightforwardly to other problems in HBChPT using the
three-flavor-index representation of the effective baryon fields, and provides
a fairly simple way to determine what parts of the loop corrections are
actually significant in a given setting.
| [
{
"created": "Thu, 19 Apr 2001 21:29:38 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Durand",
"Loyal",
""
],
[
"Ha",
"Phuoc",
""
],
[
"Jaczko",
"Gregory",
""
]
] | We analyze the structure of meson loop corrections to the O($m_s$) expressions for the baryon masses and magnetic moments in heavy-baryon chiral perturbation theory (HBChPT), and show in detail how the bulk of the corrections are absorbed into redefinitions of the unknown parameters of the O($m_s$) chiral expansion. To effect this analysis, we use the three-flavor-index representation of the effective baryon fields and HBChPT developed in a preceding paper, and a decomposition of the corrections in terms of effective one-, two-, and three-quark operators. The results show why the loop corrections have so little effect on fits to the masses and moments, and do not seriously disrupt the Gell-Mann--Okubo relations for the masses and the Okubo relation for the moments even though individual loops can be quite large. We also examine the momentum structure of the residual loop corrections, and comment on limits on their validity in HBChPT. The structural analysis can be generalized straightforwardly to other problems in HBChPT using the three-flavor-index representation of the effective baryon fields, and provides a fairly simple way to determine what parts of the loop corrections are actually significant in a given setting. |
1505.06942 | Maxim V. Polyakov | M.V. Polyakov, J. Sieverding | Heavy quark mass expansion of vector and tensor currents and intrinsic
charm in nucleon form factors | 32 pages | null | 10.1007/JHEP01(2016)092 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The framework of the expansion by subgraphs is used to compute asymptotic
expansions for the vector and the tensor currents in the limit of large quark
masses. We use the results to obtain an estimate for the influence of heavy
quarks on the nucleon electromagnetic and tensor form factors.
| [
{
"created": "Tue, 26 May 2015 13:42:04 GMT",
"version": "v1"
}
] | 2016-02-17 | [
[
"Polyakov",
"M. V.",
""
],
[
"Sieverding",
"J.",
""
]
] | The framework of the expansion by subgraphs is used to compute asymptotic expansions for the vector and the tensor currents in the limit of large quark masses. We use the results to obtain an estimate for the influence of heavy quarks on the nucleon electromagnetic and tensor form factors. |
hep-ph/9810415 | Chris Michael | Chris Michael | Hadronic Spectroscopy from the Lattice: Glueballs and Hybrid Mesons | 9 pages, latex, 5 figures, talk presented at the LEAP98 conference in
Villasimius, Sardinia, Italy | Nucl.Phys.A655:12-22,1999 | 10.1016/S0375-9474(99)00230-4 | LTH 443 | hep-ph | null | Lattice QCD determinations appropriate to hadron spectroscopy are reviewed
with emphasis on the glueball and hybrid meson states in the quenched
approximation. Hybrids are discussed for heavy and for light quarks. The
effects of sea quarks (unquenching) are explored.
| [
{
"created": "Tue, 20 Oct 1998 12:09:30 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Michael",
"Chris",
""
]
] | Lattice QCD determinations appropriate to hadron spectroscopy are reviewed with emphasis on the glueball and hybrid meson states in the quenched approximation. Hybrids are discussed for heavy and for light quarks. The effects of sea quarks (unquenching) are explored. |
2102.01448 | Min Jiang | Min Jiang, Haowen Su, Antoine Garcon, Xinhua Peng, Dmitry Budker | Search for axion-like dark matter with spin-based amplifiers | 8 pages, 4 figures | Nature Physics. 2021 Dec;17(12):1402-7 | 10.1038/s41567-021-01392-z | null | hep-ph physics.atom-ph quant-ph | http://creativecommons.org/licenses/by/4.0/ | Ultralight axion-like particles (ALPs) are well-motivated dark matter
candidates introduced by theories beyond the standard model. However, the
constraints on the existence of ALPs through existing laboratory experiments
are hindered by their current sensitivities, which are usually weaker than
astrophysical limits. Here, we demonstrate a new quantum sensor to search for
ALPs in the mass range that spans about two decades from 8.3 feV to 744 feV.
Our sensor makes use of hyperpolarized long-lived nuclear spins as a
pre-amplifier that effectively enhances coherently oscillating axion-like
dark-matter field by a factor of >100. Using spin-based amplifiers, we achieve
an ultrahigh magnetic sensitivity of 18 fT/Hz$^{1/2}$, which is significantly
better than state-of-the-art nuclear-spin magnetometers. Our experiment
constrains the parameter space describing the coupling of ALPs to nucleons over
our mass range, at 67.5 feV reaching $2.9\times 10^{-9}~\textrm{GeV}^{-1}$
($95\%$ confidence level), improving over previous laboratory limits by at
least five orders of magnitude. Our measurements also constrain the ALP-nucleon
quadratic interaction and dark photon-nucleon interaction with new limits
beyond the astrophysical ones
| [
{
"created": "Tue, 2 Feb 2021 11:48:26 GMT",
"version": "v1"
}
] | 2022-03-01 | [
[
"Jiang",
"Min",
""
],
[
"Su",
"Haowen",
""
],
[
"Garcon",
"Antoine",
""
],
[
"Peng",
"Xinhua",
""
],
[
"Budker",
"Dmitry",
""
]
] | Ultralight axion-like particles (ALPs) are well-motivated dark matter candidates introduced by theories beyond the standard model. However, the constraints on the existence of ALPs through existing laboratory experiments are hindered by their current sensitivities, which are usually weaker than astrophysical limits. Here, we demonstrate a new quantum sensor to search for ALPs in the mass range that spans about two decades from 8.3 feV to 744 feV. Our sensor makes use of hyperpolarized long-lived nuclear spins as a pre-amplifier that effectively enhances coherently oscillating axion-like dark-matter field by a factor of >100. Using spin-based amplifiers, we achieve an ultrahigh magnetic sensitivity of 18 fT/Hz$^{1/2}$, which is significantly better than state-of-the-art nuclear-spin magnetometers. Our experiment constrains the parameter space describing the coupling of ALPs to nucleons over our mass range, at 67.5 feV reaching $2.9\times 10^{-9}~\textrm{GeV}^{-1}$ ($95\%$ confidence level), improving over previous laboratory limits by at least five orders of magnitude. Our measurements also constrain the ALP-nucleon quadratic interaction and dark photon-nucleon interaction with new limits beyond the astrophysical ones |
1512.02377 | Masaki Yoshikawa | Hiroaki Nakano, Masaki Yoshikawa | Next-to-minimal $R$-symmetric model: Dirac gaugino, Higgs mass and
invisible width | 32 pages, 24 figures. typo corrected | null | 10.1093/ptep/ptw007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study a singlet extension of the minimal $U(1)_R$ symmetric model, which
shares nice properties of Dirac gauginos and $R$-symmetric Higgs sector. At the
same time, a superpotential coupling of $R$-charged singlet to the Higgs
doublets can give a substantial contribution to the Higgs boson mass. We show
that the 125 GeV Higgs boson is consistent with perturbative unification, even
if the SUSY scale is as low as 1 TeV and if the $D$-term Higgs potential is
suppressed as is often the case in Dirac gauginos. The model also contains a
light scalar and fermion, pseudo-moduli and pseudo-Goldstino: The former gets a
mass mainly from SUSY breaking soft terms, in addition to a small explicit
$R$-symmetry breaking for the latter. We examine how the Higgs mass and width
are affected by these light degrees of freedom. Specifically we find
thatdepending on parameters of $R$-charged Higgses, the pseudo-moduli lighter
than a half of the SM-Higgs boson mass is still allowed by the constraints from
invisible decays of the $Z$ and Higgs bosons. We also find that such a light
scalar can reduce the Higgs boson mass, at most by a few percents.
| [
{
"created": "Tue, 8 Dec 2015 09:25:33 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Jan 2016 06:12:35 GMT",
"version": "v2"
},
{
"created": "Thu, 24 Mar 2016 03:12:43 GMT",
"version": "v3"
}
] | 2016-03-25 | [
[
"Nakano",
"Hiroaki",
""
],
[
"Yoshikawa",
"Masaki",
""
]
] | We study a singlet extension of the minimal $U(1)_R$ symmetric model, which shares nice properties of Dirac gauginos and $R$-symmetric Higgs sector. At the same time, a superpotential coupling of $R$-charged singlet to the Higgs doublets can give a substantial contribution to the Higgs boson mass. We show that the 125 GeV Higgs boson is consistent with perturbative unification, even if the SUSY scale is as low as 1 TeV and if the $D$-term Higgs potential is suppressed as is often the case in Dirac gauginos. The model also contains a light scalar and fermion, pseudo-moduli and pseudo-Goldstino: The former gets a mass mainly from SUSY breaking soft terms, in addition to a small explicit $R$-symmetry breaking for the latter. We examine how the Higgs mass and width are affected by these light degrees of freedom. Specifically we find thatdepending on parameters of $R$-charged Higgses, the pseudo-moduli lighter than a half of the SM-Higgs boson mass is still allowed by the constraints from invisible decays of the $Z$ and Higgs bosons. We also find that such a light scalar can reduce the Higgs boson mass, at most by a few percents. |
1011.5634 | Marcus Bluhm | M. Bluhm (SUBATECH Nantes and CERN), B. Kampfer (Helmholtzzentrum
Dresden-Rossendorf and Dresden, Tech. U.), K. Redlich (Wroclaw U. and CERN) | Shear and bulk viscosities of the gluon plasma in a quasiparticle
description | Sep 2011. 24pp. 6 figures. revised journal version | Phys.Rev.C84:025201,2011 | 10.1103/PhysRevC.84.025201 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Shear and bulk viscosities of deconfined gluonic matter are investigated
within an effective kinetic theory by describing the strongly interacting
medium phenomenologically in terms of quasiparticle excitations with
medium-dependent self-energies. We show that the resulting transport
coefficients reproduce the parametric dependencies on temperature and coupling
obtained in perturbative QCD at large temperatures and small running coupling.
The extrapolation into the non-perturbative regime results in a decreasing
specific shear viscosity with decreasing temperature, exhibiting a minimum in
the vicinity of the deconfinement transition, while the specific bulk viscosity
is sizeable in this region falling off rapidly with increasing temperature. The
temperature dependence of specific shear and bulk viscosities found within this
quasiparticle description of the pure gluon plasma is in agreement with
available lattice QCD results.
| [
{
"created": "Thu, 25 Nov 2010 14:43:53 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Sep 2011 17:52:22 GMT",
"version": "v2"
}
] | 2011-09-16 | [
[
"Bluhm",
"M.",
"",
"SUBATECH Nantes and CERN"
],
[
"Kampfer",
"B.",
"",
"Helmholtzzentrum\n Dresden-Rossendorf and Dresden, Tech. U."
],
[
"Redlich",
"K.",
"",
"Wroclaw U. and CERN"
]
] | Shear and bulk viscosities of deconfined gluonic matter are investigated within an effective kinetic theory by describing the strongly interacting medium phenomenologically in terms of quasiparticle excitations with medium-dependent self-energies. We show that the resulting transport coefficients reproduce the parametric dependencies on temperature and coupling obtained in perturbative QCD at large temperatures and small running coupling. The extrapolation into the non-perturbative regime results in a decreasing specific shear viscosity with decreasing temperature, exhibiting a minimum in the vicinity of the deconfinement transition, while the specific bulk viscosity is sizeable in this region falling off rapidly with increasing temperature. The temperature dependence of specific shear and bulk viscosities found within this quasiparticle description of the pure gluon plasma is in agreement with available lattice QCD results. |
1705.06716 | Kamuran Dilsiz | Kamuran Dilsiz, Emrah Tiras | Cross Section Predictions of W ($W\to\ell^{\pm}\nu$) and Z
($Z\to\ell^{+}\ell^{-}$) Bosons in Association with Jets in pp Collisions | This study needs many modifications | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Cross section predictions of W and Z bosons in association with jets (up to 6
jets, $W\to\ell^{\pm}\nu$ and $Z\to\ell^{\pm}$ where $\ell^{\pm}$=$e^{\pm}$ or
$\mu^{\pm}$) in proton-proton collisions at $\sqrt{s}$=14 TeV is performed
using Alpgen MC generator with CTEQ6L1 leading order parton distribution
function. In addition, W and Z boson cross sections are obtained up to next to
next to leading order (NNLO) QCD corrections using MCFM MC generator. To
validate the predictions, a detailed comparison of NNLO QCD calculations with 8
TeV CMS results for total cross section is performed and a fiducial region is
further defined to make a comparison of predictions with 7 TeV and 13 TeV ATLAS
results.
| [
{
"created": "Thu, 18 May 2017 17:39:39 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Sep 2017 23:37:08 GMT",
"version": "v2"
},
{
"created": "Mon, 18 Sep 2017 12:48:03 GMT",
"version": "v3"
}
] | 2017-09-19 | [
[
"Dilsiz",
"Kamuran",
""
],
[
"Tiras",
"Emrah",
""
]
] | Cross section predictions of W and Z bosons in association with jets (up to 6 jets, $W\to\ell^{\pm}\nu$ and $Z\to\ell^{\pm}$ where $\ell^{\pm}$=$e^{\pm}$ or $\mu^{\pm}$) in proton-proton collisions at $\sqrt{s}$=14 TeV is performed using Alpgen MC generator with CTEQ6L1 leading order parton distribution function. In addition, W and Z boson cross sections are obtained up to next to next to leading order (NNLO) QCD corrections using MCFM MC generator. To validate the predictions, a detailed comparison of NNLO QCD calculations with 8 TeV CMS results for total cross section is performed and a fiducial region is further defined to make a comparison of predictions with 7 TeV and 13 TeV ATLAS results. |
1502.07546 | Avelino Vicente | Sofiane M. Boucenna, Jose W. F. Valle, Avelino Vicente | Predicting charged lepton flavor violation from 3-3-1 gauge symmetry | 7 pages, 2 figures; v2: discussion extended. Matches version
published in PRD | Phys. Rev. D 92, 053001 (2015) | 10.1103/PhysRevD.92.053001 | IFIC/15-11 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The simplest realization of the inverse seesaw mechanism in a $SU(3)_C
\otimes SU(3)_L \otimes U(1)_X$ gauge theory offers striking flavor
correlations between rare charged lepton flavor violating decays and the
measured neutrino oscillations parameters. The predictions follow from the
gauge structure itself without the need for any flavor symmetry. Such tight
complementarity between charged lepton flavor violation and oscillations
renders the scenario strictly testable.
| [
{
"created": "Thu, 26 Feb 2015 13:30:16 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Sep 2015 12:49:08 GMT",
"version": "v2"
}
] | 2015-09-16 | [
[
"Boucenna",
"Sofiane M.",
""
],
[
"Valle",
"Jose W. F.",
""
],
[
"Vicente",
"Avelino",
""
]
] | The simplest realization of the inverse seesaw mechanism in a $SU(3)_C \otimes SU(3)_L \otimes U(1)_X$ gauge theory offers striking flavor correlations between rare charged lepton flavor violating decays and the measured neutrino oscillations parameters. The predictions follow from the gauge structure itself without the need for any flavor symmetry. Such tight complementarity between charged lepton flavor violation and oscillations renders the scenario strictly testable. |
hep-ph/9601272 | Ilya F. Ginzburg | Ilya F. Ginzburg | Initial Particle Instability in Muon Collisions | 5 pages, no figures; Talk given at 3 Int. Conference on Physics
Potential and Development of mumu Colliders, San Francisco, December 13-15,
1995 | Nucl.Phys.Proc.Suppl. 51A (1996) 85-89 | null | IM SO RAN Preprint -96 -1/201 | hep-ph | null | I consider the process $\mu^+\mu^-\to e\bar{\nu}W^+$ in the case when the
effective mass of the $(e\bar\nu)$ system than the muon mass. In this case the
momentum transferred from the initial muon to the $e\bar\nu$ system (the
virtual neutrino momentum) can be both time--like and space--like. Since the
path of integration over $k^2$ goes through a pole at $k^2=0$, it gives a
divergent cross section. In the ideal case of large enough beams this
divergence disappears if the finite width $\Gamma$ of the initial muon is taken
into account. The obtained cross section corresponds to the flux of equivalent
neutrino, which coincides with that of muon (with some energy distribution). In
practice, the effect of final size of the muon beam reduces this cross section
very strong, and the effect is hardly observable.
| [
{
"created": "Tue, 16 Jan 1996 06:38:04 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Ginzburg",
"Ilya F.",
""
]
] | I consider the process $\mu^+\mu^-\to e\bar{\nu}W^+$ in the case when the effective mass of the $(e\bar\nu)$ system than the muon mass. In this case the momentum transferred from the initial muon to the $e\bar\nu$ system (the virtual neutrino momentum) can be both time--like and space--like. Since the path of integration over $k^2$ goes through a pole at $k^2=0$, it gives a divergent cross section. In the ideal case of large enough beams this divergence disappears if the finite width $\Gamma$ of the initial muon is taken into account. The obtained cross section corresponds to the flux of equivalent neutrino, which coincides with that of muon (with some energy distribution). In practice, the effect of final size of the muon beam reduces this cross section very strong, and the effect is hardly observable. |
0811.2427 | Ki-Young Choi | Ki-Young Choi, Leszek Roszkowski, Roberto Ruiz de Austri | Determining Reheating Temperature at LHC with Axino or Gravitino Dark
Matter | 6 pages, 8 figures, Submitted for the DSU proceedings to be published
by the American institute of Physics (AIP) | AIP Conf.Proc.1115:27-32,2009 | 10.1063/1.3131512 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | After a period of inflationary expansion, the Universe reheated and reached
full thermal equilibrium at the reheating temperature. In this talk, based on
the paper, arXiv:0710.3349, we point out that, in the context of effective
low-energy supersymmetric models, LHC measurements may allow one to determine
reheating temperature as a function of the mass of the dark matter particle
assumed to be either an axino or a gravitino. An upper bound on their mass and
on the reheating temperature may also be derived.
| [
{
"created": "Fri, 14 Nov 2008 21:31:52 GMT",
"version": "v1"
}
] | 2009-05-01 | [
[
"Choi",
"Ki-Young",
""
],
[
"Roszkowski",
"Leszek",
""
],
[
"de Austri",
"Roberto Ruiz",
""
]
] | After a period of inflationary expansion, the Universe reheated and reached full thermal equilibrium at the reheating temperature. In this talk, based on the paper, arXiv:0710.3349, we point out that, in the context of effective low-energy supersymmetric models, LHC measurements may allow one to determine reheating temperature as a function of the mass of the dark matter particle assumed to be either an axino or a gravitino. An upper bound on their mass and on the reheating temperature may also be derived. |
2302.05926 | J.K. Chen | Jiao-Kai Chen | Regge trajectory relation for the universal description of the
heavy-heavy systems: diquarks, mesons, baryons and tetraquarks | 9 pages, 5 figures and 6 tables | Nucl. Phys.A1050(2024)122927 | 10.1016/j.nuclphysa.2024.122927 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | By employing the nonlinear Regge trajectory relation
$M=m_R+\beta_x(x+c_{0x})^{2/3}\,\,(x=l,\,n_r)$, we investigate the heavy-heavy
systems, such as the doubly heavy diquarks, the doubly heavy mesons, the
heavy-heavy baryons, and the heavy-heavy tetraquarks. The fitted Regge
trajectories illustrate that these heavy-heavy systems satisfy the above
formula and show the existence of an universal description of the heavy-heavy
systems. The universality embodies not only the universal behavior
$M{\sim}x^{2/3}$ but also the universal parameters. The values of $c_{fn_r}$
and $c_{fl}$ vary with different heavy-heavy systems, but they are close to
one. There is an inequality $\beta_{n_r}>\beta_{l}$, and it holds for all the
discussed heavy-heavy systems. Moreover, the expression of $\beta_x$ [Eq. (11)]
explains its variation with the change of the constituents' masses.
| [
{
"created": "Sun, 12 Feb 2023 14:37:23 GMT",
"version": "v1"
},
{
"created": "Sun, 12 Nov 2023 09:08:18 GMT",
"version": "v2"
},
{
"created": "Tue, 16 Jul 2024 11:07:23 GMT",
"version": "v3"
}
] | 2024-07-17 | [
[
"Chen",
"Jiao-Kai",
""
]
] | By employing the nonlinear Regge trajectory relation $M=m_R+\beta_x(x+c_{0x})^{2/3}\,\,(x=l,\,n_r)$, we investigate the heavy-heavy systems, such as the doubly heavy diquarks, the doubly heavy mesons, the heavy-heavy baryons, and the heavy-heavy tetraquarks. The fitted Regge trajectories illustrate that these heavy-heavy systems satisfy the above formula and show the existence of an universal description of the heavy-heavy systems. The universality embodies not only the universal behavior $M{\sim}x^{2/3}$ but also the universal parameters. The values of $c_{fn_r}$ and $c_{fl}$ vary with different heavy-heavy systems, but they are close to one. There is an inequality $\beta_{n_r}>\beta_{l}$, and it holds for all the discussed heavy-heavy systems. Moreover, the expression of $\beta_x$ [Eq. (11)] explains its variation with the change of the constituents' masses. |
1505.01039 | Toshifumi Yamashita | T. Yamashita | Higgs as a probe of supersymmetric grand unification with the Hosotani
mechanism | 4 pages, 3 figures. Talk given at the 2nd Toyama International
Workshop on Higgs as a Probe of New Physics 2015, 11-15 February 2015,
Toyama, Japan | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The supersymmetric grand unified theory where the $SU(5)$ gauge symmetry is
broken by the Hosotani mechanism provides a natural solution to the so-called
doublet-triplet splitting problem. At the same time, this model derives a
general and distinctive prediction that is testable at TeV scale collider
experiments. To be more concrete, adjoint chiral supermultiplets with masses
around TeV scale appear. Since these additional fields originate from a
higher-dimensional gauge supermultiplet, our model is highly predictive. We
study especially the Higgs sector and show that our model is discriminative
from the others by precision measurements of the couplings and masses. Namely,
we may get a hint of the breaking mechanism of the grand unification at future
collider experiments.
| [
{
"created": "Tue, 5 May 2015 15:23:43 GMT",
"version": "v1"
}
] | 2015-05-06 | [
[
"Yamashita",
"T.",
""
]
] | The supersymmetric grand unified theory where the $SU(5)$ gauge symmetry is broken by the Hosotani mechanism provides a natural solution to the so-called doublet-triplet splitting problem. At the same time, this model derives a general and distinctive prediction that is testable at TeV scale collider experiments. To be more concrete, adjoint chiral supermultiplets with masses around TeV scale appear. Since these additional fields originate from a higher-dimensional gauge supermultiplet, our model is highly predictive. We study especially the Higgs sector and show that our model is discriminative from the others by precision measurements of the couplings and masses. Namely, we may get a hint of the breaking mechanism of the grand unification at future collider experiments. |
2309.11562 | Matthew Baumgart | Matthew Baumgart, Nicholas L. Rodd, Tracy R. Slatyer, and Varun Vaidya | The Quintuplet Annihilation Spectrum | 85 pages, 14 figures; v2: appendix and figures added on rapid
variation of annihilation rate with mass | null | null | null | hep-ph astro-ph.CO astro-ph.HE hep-th | http://creativecommons.org/licenses/by/4.0/ | We extend the Effective Field Theory of Heavy Dark Matter to arbitrary odd
representations of SU(2) and incorporate the effects of bound states. This
formalism is then deployed to compute the gamma-ray spectrum for a 5 of SU(2):
quintuplet dark matter. Except at isolated values of the quintuplet mass, the
bound state contribution to hard photons with energy near the dark-matter mass
is at the level of a few percent compared to that from direct annihilation.
Further, compared to smaller representations, such as the triplet wino, the
quintuplet can exhibit a strong variation in the shape of the spectrum as a
function of mass. Using our results, we forecast the fate of the thermal
quintuplet, which has a mass of $\sim$13.6 TeV. We find that existing H.E.S.S.
data should be able to significantly test the scenario, however, the final word
on this canonical model of minimal dark matter will likely be left to the
Cherenkov Telescope Array (CTA).
| [
{
"created": "Wed, 20 Sep 2023 18:02:11 GMT",
"version": "v1"
},
{
"created": "Sun, 14 Jan 2024 22:19:51 GMT",
"version": "v2"
}
] | 2024-01-17 | [
[
"Baumgart",
"Matthew",
""
],
[
"Rodd",
"Nicholas L.",
""
],
[
"Slatyer",
"Tracy R.",
""
],
[
"Vaidya",
"Varun",
""
]
] | We extend the Effective Field Theory of Heavy Dark Matter to arbitrary odd representations of SU(2) and incorporate the effects of bound states. This formalism is then deployed to compute the gamma-ray spectrum for a 5 of SU(2): quintuplet dark matter. Except at isolated values of the quintuplet mass, the bound state contribution to hard photons with energy near the dark-matter mass is at the level of a few percent compared to that from direct annihilation. Further, compared to smaller representations, such as the triplet wino, the quintuplet can exhibit a strong variation in the shape of the spectrum as a function of mass. Using our results, we forecast the fate of the thermal quintuplet, which has a mass of $\sim$13.6 TeV. We find that existing H.E.S.S. data should be able to significantly test the scenario, however, the final word on this canonical model of minimal dark matter will likely be left to the Cherenkov Telescope Array (CTA). |
1509.04590 | Nejc Ko\v{s}nik | Nejc Ko\v{s}nik | New Physics Models Facing Lepton Flavor Violating Higgs Decays | To be published in the proceedings of CHARM-2015, Detroit, MI, 18-22
May 2015 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We speculate about the possible interpretations of the recently observed
excess in the $h \to \tau \mu$ decay. We derive a robust lower bound on the
Higgs boson coupling strength to a tau and a muon, even in presence of the most
general new physics affecting other Higgs properties. Then we reevaluate
complementary indirect constraints coming from low energy observables as well
as from theoretical considerations. In particular, the tentative signal should
lead to $\tau \to \mu \gamma$ at rates which could be observed at Belle II. In
turn we show that, barring fine-tuned cancellations, the effect can be
accommodated within models with an extended scalar sector. These general
conclusions are demonstrated in explicit new physics models. Finally we show
how, given the $h \to \tau \mu$ signal, the current and future searches for
$\mu \to e \gamma$ and $\mu \to e$ nuclear conversions unambiguously constrain
the allowed rates for $h \to \tau e$.
| [
{
"created": "Tue, 15 Sep 2015 14:53:13 GMT",
"version": "v1"
}
] | 2015-09-16 | [
[
"Košnik",
"Nejc",
""
]
] | We speculate about the possible interpretations of the recently observed excess in the $h \to \tau \mu$ decay. We derive a robust lower bound on the Higgs boson coupling strength to a tau and a muon, even in presence of the most general new physics affecting other Higgs properties. Then we reevaluate complementary indirect constraints coming from low energy observables as well as from theoretical considerations. In particular, the tentative signal should lead to $\tau \to \mu \gamma$ at rates which could be observed at Belle II. In turn we show that, barring fine-tuned cancellations, the effect can be accommodated within models with an extended scalar sector. These general conclusions are demonstrated in explicit new physics models. Finally we show how, given the $h \to \tau \mu$ signal, the current and future searches for $\mu \to e \gamma$ and $\mu \to e$ nuclear conversions unambiguously constrain the allowed rates for $h \to \tau e$. |
hep-ph/9912426 | R. Floreanini | F. Benatti and R. Floreanini | CPT, dissipation, and all that | 16 pages, plain-TeX, talk given by R.F. at Daphne99, Frascati,
November 16-19, 1999 | null | null | null | hep-ph hep-th | null | A phenomenological paradigm for the study of CPT-violating effects in the
neutral kaon system is presented. Besides the familiar direct and indirect
breakings, it encodes possible phenomena leading to irreversibility and
dissipation, that could originate from quantum effects at Planck's scale. These
new effects can be experimentally probed with great accuracy, in particular at
phi-factories.
| [
{
"created": "Mon, 20 Dec 1999 14:30:53 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Benatti",
"F.",
""
],
[
"Floreanini",
"R.",
""
]
] | A phenomenological paradigm for the study of CPT-violating effects in the neutral kaon system is presented. Besides the familiar direct and indirect breakings, it encodes possible phenomena leading to irreversibility and dissipation, that could originate from quantum effects at Planck's scale. These new effects can be experimentally probed with great accuracy, in particular at phi-factories. |
0711.4646 | Alexander Kusenko | Kalliopi Petraki and Alexander Kusenko | Dark-matter sterile neutrinos in models with a gauge singlet in the
Higgs sector | 12 pages, 7 figures | Phys.Rev.D77:065014,2008 | 10.1103/PhysRevD.77.065014 | UCLA/07/TEP/27 | hep-ph astro-ph | null | Sterile neutrino with mass of several keV can be the cosmological dark
matter, can explain the observed velocities of pulsars, and can play an
important role in the formation of the first stars. We describe the production
of sterile neutrinos in a model with an extended Higgs sector, in which the
Majorana mass term is generated by the vacuum expectation value of a
gauge-singlet Higgs boson. In this model the relic abundance of sterile
neutrinos does not necessarily depend on their mixing angles, the
free-streaming length can be much smaller than in the case of warm dark matter
produced by neutrino oscillations, and, therefore, some of the previously
quoted bounds do not apply. The presence of the gauge singlet in the Higgs
sector has important implications for the electroweak phase transition,
baryogenesis, and the upcoming experiments at the Large Hadron Collider and a
Linear Collider.
| [
{
"created": "Thu, 29 Nov 2007 20:13:52 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Dec 2007 23:53:50 GMT",
"version": "v2"
},
{
"created": "Wed, 5 Mar 2008 21:07:49 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Petraki",
"Kalliopi",
""
],
[
"Kusenko",
"Alexander",
""
]
] | Sterile neutrino with mass of several keV can be the cosmological dark matter, can explain the observed velocities of pulsars, and can play an important role in the formation of the first stars. We describe the production of sterile neutrinos in a model with an extended Higgs sector, in which the Majorana mass term is generated by the vacuum expectation value of a gauge-singlet Higgs boson. In this model the relic abundance of sterile neutrinos does not necessarily depend on their mixing angles, the free-streaming length can be much smaller than in the case of warm dark matter produced by neutrino oscillations, and, therefore, some of the previously quoted bounds do not apply. The presence of the gauge singlet in the Higgs sector has important implications for the electroweak phase transition, baryogenesis, and the upcoming experiments at the Large Hadron Collider and a Linear Collider. |
1903.11001 | Hua-Xing Chen | Hua-Xing Chen, Wei Chen and Shi-Lin Zhu | Possible interpretations of the $P_c(4312)$, $P_c(4440)$, and
$P_c(4457)$ | 5 pages, 1 figure, 1 table, revised version published in PRD | Phys. Rev. D 100, 051501 (2019) | 10.1103/PhysRevD.100.051501 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based on our previous QCD sum rule studies on hidden-charm pentaquark states,
we discuss possible interpretations of the $P_c(4312)$, $P_c(4440)$, and
$P_c(4457)$, which were recently observed by LHCb. Our results suggest that the
$P_c(4312)$ can be well interpreted as the $[\Sigma_c^{++} \bar D^-]$ bound
state with $J^P = 1/2^-$, while the $P_c(4440)$ and $P_c(4457)$ can be
interpreted as the $[\Sigma_c^{+} \bar D^0]$ bound state with $J^P = 1/2^-$,
the $[\Sigma_c^{*++} \bar D^{-}]$ and $[\Sigma_c^{+} \bar D^{*0}]$ bound states
with $J^P = 3/2^-$, or the $[\Sigma_c^{*+} \bar D^{*0}]$ bound state with $J^P
= 5/2^-$. We propose to measure their spin-parity quantum numbers to verify
these assignments.
| [
{
"created": "Tue, 26 Mar 2019 16:41:46 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Mar 2019 12:48:59 GMT",
"version": "v2"
},
{
"created": "Sat, 28 Sep 2019 10:55:04 GMT",
"version": "v3"
}
] | 2019-10-01 | [
[
"Chen",
"Hua-Xing",
""
],
[
"Chen",
"Wei",
""
],
[
"Zhu",
"Shi-Lin",
""
]
] | Based on our previous QCD sum rule studies on hidden-charm pentaquark states, we discuss possible interpretations of the $P_c(4312)$, $P_c(4440)$, and $P_c(4457)$, which were recently observed by LHCb. Our results suggest that the $P_c(4312)$ can be well interpreted as the $[\Sigma_c^{++} \bar D^-]$ bound state with $J^P = 1/2^-$, while the $P_c(4440)$ and $P_c(4457)$ can be interpreted as the $[\Sigma_c^{+} \bar D^0]$ bound state with $J^P = 1/2^-$, the $[\Sigma_c^{*++} \bar D^{-}]$ and $[\Sigma_c^{+} \bar D^{*0}]$ bound states with $J^P = 3/2^-$, or the $[\Sigma_c^{*+} \bar D^{*0}]$ bound state with $J^P = 5/2^-$. We propose to measure their spin-parity quantum numbers to verify these assignments. |
hep-ph/0602175 | Cheng-Wei Chiang | Abdesslam Arhrib, Kingman Cheung, Cheng-Wei Chiang, and Tzu-Chiang
Yuan | Single Top-Quark Production in Flavor-Changing Z' Models | 22 pages, 6 figures; references added, submitted to Phys. Rev. D | Phys.Rev.D73:075015,2006 | 10.1103/PhysRevD.73.075015 | null | hep-ph | null | In some models with an extra U(1) gauge boson Z', the gauge couplings of the
Z' to different generations of fermions may not be universal. Flavor mixing in
general can be induced at the tree level in the up-type and/or down-type quark
sector after diagonalizing their mass matrices. In this work, we concentrate on
the flavor mixing in the up-type quark sector. We deduce a constraint from
D0-D0bar mixing. We study in detail single top-quark production via
flavor-changing Z' exchange at the LHC and the ILC. We found that for a typical
value of M_{Z'}=1 TeV, the production cross section at the LHC can be of the
order of 1 fb. However, the background from the Standard Model single top-quark
production makes it difficult to detect the flavor-changing Z' signal unless
with a decent charm tagging method. On the other hand, at the ILC, the
production cross section at the resonance energy of \sqrt{s} \approx M_{Z'} can
reach a size of more than 100 fb. Even away from the resonance, the cross
section at ILC is shown to be larger than the threshold of observability of
0.01 fb.
| [
{
"created": "Mon, 20 Feb 2006 00:58:51 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Feb 2006 04:21:38 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Arhrib",
"Abdesslam",
""
],
[
"Cheung",
"Kingman",
""
],
[
"Chiang",
"Cheng-Wei",
""
],
[
"Yuan",
"Tzu-Chiang",
""
]
] | In some models with an extra U(1) gauge boson Z', the gauge couplings of the Z' to different generations of fermions may not be universal. Flavor mixing in general can be induced at the tree level in the up-type and/or down-type quark sector after diagonalizing their mass matrices. In this work, we concentrate on the flavor mixing in the up-type quark sector. We deduce a constraint from D0-D0bar mixing. We study in detail single top-quark production via flavor-changing Z' exchange at the LHC and the ILC. We found that for a typical value of M_{Z'}=1 TeV, the production cross section at the LHC can be of the order of 1 fb. However, the background from the Standard Model single top-quark production makes it difficult to detect the flavor-changing Z' signal unless with a decent charm tagging method. On the other hand, at the ILC, the production cross section at the resonance energy of \sqrt{s} \approx M_{Z'} can reach a size of more than 100 fb. Even away from the resonance, the cross section at ILC is shown to be larger than the threshold of observability of 0.01 fb. |
1708.02830 | Pran Nath | Amin Aboubrahim and Pran Nath | Supergravity Models with 50-100 TeV Scalars, SUSY Discovery at the LHC
and Gravitino Decay Constraints | 34 pages, 10 figures. arXiv admin note: text overlap with
arXiv:1704.04669 | Phys. Rev. D 96, 075015 (2017) | 10.1103/PhysRevD.96.075015 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the possibility of testing supergravity unified models with
scalar masses in the range 50-100 TeV and much lighter gaugino masses at the
Large Hadron Collider. The analysis is carried out under the constraints that
models produce the Higgs boson mass consistent with experiment and also produce
dark matter consistent with WMAP and PLANCK experiments. A set of benchmarks in
the supergravity parameter space are investigated using a combination of signal
regions which are optimized for the model set. It is found that some of the
models with scalar masses in the 50-100 TeV mass range are discoverable with as
little as 100 fb$^{-1}$ of integrated luminosity and should be accessible at
the LHC RUN II. The remaining benchmark models are found to be discoverable
with less than 1000 fb$^{-1}$ of integrated luminosity and thus testable in the
high luminosity era of the LHC, i.e., at HL-LHC. It is shown that scalar masses
in the 50-100 TeV range but gaugino masses much lower in mass produce
unification of gauge coupling constants, consistent with experimental data at
low scale, with as good an accuracy (and sometimes even better) as models with
low ($\mathcal{O}(1)$ TeV) weak scale supersymmetry. Decay of the gravitinos
for the supergravity model benchmarks are investigated and it is shown that
they decay before the Big Bang Nucleosynthesis (BBN). Further, we investigate
the non-thermal production of neutralinos from gravitino decay and it is found
that the non-thermal contribution to the dark matter relic density is
negligible relative to that from the thermal production of neutralinos for
reheat temperature after inflation up to $10^9$ GeV. An analysis of the direct
detection of dark matter for SUGRA models with high scalar masses is also
discussed.
| [
{
"created": "Mon, 7 Aug 2017 20:00:03 GMT",
"version": "v1"
}
] | 2017-10-18 | [
[
"Aboubrahim",
"Amin",
""
],
[
"Nath",
"Pran",
""
]
] | We investigate the possibility of testing supergravity unified models with scalar masses in the range 50-100 TeV and much lighter gaugino masses at the Large Hadron Collider. The analysis is carried out under the constraints that models produce the Higgs boson mass consistent with experiment and also produce dark matter consistent with WMAP and PLANCK experiments. A set of benchmarks in the supergravity parameter space are investigated using a combination of signal regions which are optimized for the model set. It is found that some of the models with scalar masses in the 50-100 TeV mass range are discoverable with as little as 100 fb$^{-1}$ of integrated luminosity and should be accessible at the LHC RUN II. The remaining benchmark models are found to be discoverable with less than 1000 fb$^{-1}$ of integrated luminosity and thus testable in the high luminosity era of the LHC, i.e., at HL-LHC. It is shown that scalar masses in the 50-100 TeV range but gaugino masses much lower in mass produce unification of gauge coupling constants, consistent with experimental data at low scale, with as good an accuracy (and sometimes even better) as models with low ($\mathcal{O}(1)$ TeV) weak scale supersymmetry. Decay of the gravitinos for the supergravity model benchmarks are investigated and it is shown that they decay before the Big Bang Nucleosynthesis (BBN). Further, we investigate the non-thermal production of neutralinos from gravitino decay and it is found that the non-thermal contribution to the dark matter relic density is negligible relative to that from the thermal production of neutralinos for reheat temperature after inflation up to $10^9$ GeV. An analysis of the direct detection of dark matter for SUGRA models with high scalar masses is also discussed. |
hep-ph/0003038 | Teshima Tadayuki | T. Teshima and T. Sakai | Analysis of atmospheric neutrino oscillations in three-flavor neutrinos | 16 pages, 3 figures, LaTeX | Phys.Rev. D62 (2000) 113010 | 10.1103/PhysRevD.62.113010 | CU-TP/00-03 | hep-ph | null | We analyze the atmospheric neutrino experiments of Super-Kamiokande (830-920
live days) using the three-flavor neutrino framework with the mass hierarchy
m_1 nearly equal m_2 << m_3. We study the sub-GeV, multi- GeV neutrinos and
upward through-going and stopping muons zenith angle distributions taking
account of the Earth matter effects thoroughly. We obtain the allowed regions
of mass and mixing parameters Delm^2_{23}, theta_{13} and theta_{23}.
Delm^2_{23} is restricted to 0.002-0.01eV^2 and theta_{13}<13degrees,
35degrees<theta_{23}<55degrees in 90% C.L. For theta_{12}, there is no
difference between the large angle solar neutrino solution and small one. From
chi^2 fit, the minimum chi^2=55(54DOF) is obtained at
Delm^2_{23}=4x10^(-3)eV^2, theta_{13}=10degrees and theta_{23} =45degrees.
| [
{
"created": "Mon, 6 Mar 2000 07:34:27 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Teshima",
"T.",
""
],
[
"Sakai",
"T.",
""
]
] | We analyze the atmospheric neutrino experiments of Super-Kamiokande (830-920 live days) using the three-flavor neutrino framework with the mass hierarchy m_1 nearly equal m_2 << m_3. We study the sub-GeV, multi- GeV neutrinos and upward through-going and stopping muons zenith angle distributions taking account of the Earth matter effects thoroughly. We obtain the allowed regions of mass and mixing parameters Delm^2_{23}, theta_{13} and theta_{23}. Delm^2_{23} is restricted to 0.002-0.01eV^2 and theta_{13}<13degrees, 35degrees<theta_{23}<55degrees in 90% C.L. For theta_{12}, there is no difference between the large angle solar neutrino solution and small one. From chi^2 fit, the minimum chi^2=55(54DOF) is obtained at Delm^2_{23}=4x10^(-3)eV^2, theta_{13}=10degrees and theta_{23} =45degrees. |
0903.0618 | Patrick Huber | Hooman Davoudiasl, Patrick Huber | Thermal Geo-axions | 4 pages, 1 figure | Phys.Rev.D79:095024,2009 | 10.1103/PhysRevD.79.095024 | null | hep-ph astro-ph.HE hep-ex | http://creativecommons.org/licenses/publicdomain/ | We estimate the production rate of axion-type particles in the core of the
Earth, at a temperature T~5000K. We constrain thermal geo-axion emission by
demanding a core-cooling rate less than 100K/Gyr, as suggested by geophysics.
This yields a "quasi-vacuum" (unaffected by extreme stellar conditions) bound
on the axion-electron fine structure constant \alpha_a^{QV} < 10^{-18},
stronger than the existing accelerator (vacuum) bound by 4 orders of magnitude.
We consider the prospects for measuring the geo-axion flux through conversion
into photons in a geoscope; such measurements can further constrain
\alpha_a^{QV}.
| [
{
"created": "Tue, 3 Mar 2009 21:00:30 GMT",
"version": "v1"
}
] | 2010-04-15 | [
[
"Davoudiasl",
"Hooman",
""
],
[
"Huber",
"Patrick",
""
]
] | We estimate the production rate of axion-type particles in the core of the Earth, at a temperature T~5000K. We constrain thermal geo-axion emission by demanding a core-cooling rate less than 100K/Gyr, as suggested by geophysics. This yields a "quasi-vacuum" (unaffected by extreme stellar conditions) bound on the axion-electron fine structure constant \alpha_a^{QV} < 10^{-18}, stronger than the existing accelerator (vacuum) bound by 4 orders of magnitude. We consider the prospects for measuring the geo-axion flux through conversion into photons in a geoscope; such measurements can further constrain \alpha_a^{QV}. |
1610.03494 | Gilberto Colangelo | Gilberto Colangelo, Stefan Lanz, Heinrich Leutwyler and Emilie
Passemar | The decay $\eta \to 3 \pi$: study of the Dalitz plot and extraction of
the quark mass ratio $Q$ | 5 pages, 1 figure, v2 = published version. Slightly shorter and with
minor changes | Phys. Rev. Lett. 118, 022001 (2017) | 10.1103/PhysRevLett.118.022001 | JLAB-THY-16-2360 | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $\eta \to 3 \pi$ amplitude is sensitive to the quark mass difference
$m_u-m_d$ and offers a unique way to determine the quark mass ratio $Q^2 \equiv
(m_s^2-m_{ud}^2)/(m_d^2-m_u^2)$ from experiment. We calculate the amplitude
dispersively and fit the KLOE data on the charged mode, varying the subtraction
constants in the range allowed by chiral perturbation theory. The
parameter-free predictions obtained for the neutral Dalitz plot and the
neutral-to-charged branching ratio are in excellent agreement with experiment.
Our representation of the transition amplitude implies $Q = 22.0 \pm 0.7$.
| [
{
"created": "Tue, 11 Oct 2016 20:00:06 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Jan 2017 14:15:01 GMT",
"version": "v2"
}
] | 2017-01-23 | [
[
"Colangelo",
"Gilberto",
""
],
[
"Lanz",
"Stefan",
""
],
[
"Leutwyler",
"Heinrich",
""
],
[
"Passemar",
"Emilie",
""
]
] | The $\eta \to 3 \pi$ amplitude is sensitive to the quark mass difference $m_u-m_d$ and offers a unique way to determine the quark mass ratio $Q^2 \equiv (m_s^2-m_{ud}^2)/(m_d^2-m_u^2)$ from experiment. We calculate the amplitude dispersively and fit the KLOE data on the charged mode, varying the subtraction constants in the range allowed by chiral perturbation theory. The parameter-free predictions obtained for the neutral Dalitz plot and the neutral-to-charged branching ratio are in excellent agreement with experiment. Our representation of the transition amplitude implies $Q = 22.0 \pm 0.7$. |
1406.6925 | Monoranjan Guchait | Siba Prasad Das, Monoranjan Guchait, D. P. Roy | Testing SUSY models for the muon g-2 anomaly via Chargino-Neutralino
Pair Production at the LHC | 14 pages, version to be published in PRD | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Non-universal gaugino mass models can naturally account for the dark matter
relic density via the bulk annihilation process with relatively light bino LSP
and right sleptons in the mass range of ~ 100 GeV, while accommodating the
observed Higgs boson mass of ~ 125 GeV with TeV scale squark/gluino masses. A
class of these models can also account for the observed muon g-2 anomaly via
SUSY loops with wino and left sleptons in the mass range of 400 -- 700 GeV.
These models can be tested at LHC via electroweak production of charged and
neutral wino pair, leading to robust trilepton and same sign dilepton signals.
We investigate these signals along with the standard model background for both
8 and 13 TeV LHC runs.
| [
{
"created": "Thu, 26 Jun 2014 15:35:08 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Jul 2014 14:13:40 GMT",
"version": "v2"
},
{
"created": "Mon, 13 Oct 2014 19:04:20 GMT",
"version": "v3"
}
] | 2014-10-14 | [
[
"Das",
"Siba Prasad",
""
],
[
"Guchait",
"Monoranjan",
""
],
[
"Roy",
"D. P.",
""
]
] | Non-universal gaugino mass models can naturally account for the dark matter relic density via the bulk annihilation process with relatively light bino LSP and right sleptons in the mass range of ~ 100 GeV, while accommodating the observed Higgs boson mass of ~ 125 GeV with TeV scale squark/gluino masses. A class of these models can also account for the observed muon g-2 anomaly via SUSY loops with wino and left sleptons in the mass range of 400 -- 700 GeV. These models can be tested at LHC via electroweak production of charged and neutral wino pair, leading to robust trilepton and same sign dilepton signals. We investigate these signals along with the standard model background for both 8 and 13 TeV LHC runs. |
hep-ph/0502221 | Edmond Iancu | J.-P. Blaizot, E. Iancu, K. Itakura, D.N. Triantafyllopoulos | Duality and Pomeron effective theory for QCD at high energy and large
N_c | 13 pages, 1 figure | Phys.Lett. B615 (2005) 221-230 | 10.1016/j.physletb.2005.04.009 | SACLAY-T05/031 | hep-ph | null | We propose an effective theory which governs Pomeron dynamics in QCD at high
energy, in the leading logarithmic approximation, and in the limit where N_c,
the number of colors, is large. In spite of its remarkably simple structure,
this effective theory generates precisely the evolution equations for
scattering amplitudes that have been recently deduced from a more complete
microscopic analysis. It accounts for the BFKL evolution of the Pomerons
together with their interactions: dissociation (one Pomeron splitting into two)
and recombination (two Pomerons merging into one). It is constructed by
exploiting a duality principle relating the evolutions in the target and the
projectile, more precisely, splitting and merging processes, or fluctuations in
the dilute regime and saturation effects in the dense regime. The simplest
Pomeron loop calculated with the effective theory is free of both ultraviolet
or infrared singularities.
| [
{
"created": "Wed, 23 Feb 2005 20:36:43 GMT",
"version": "v1"
}
] | 2016-09-06 | [
[
"Blaizot",
"J. -P.",
""
],
[
"Iancu",
"E.",
""
],
[
"Itakura",
"K.",
""
],
[
"Triantafyllopoulos",
"D. N.",
""
]
] | We propose an effective theory which governs Pomeron dynamics in QCD at high energy, in the leading logarithmic approximation, and in the limit where N_c, the number of colors, is large. In spite of its remarkably simple structure, this effective theory generates precisely the evolution equations for scattering amplitudes that have been recently deduced from a more complete microscopic analysis. It accounts for the BFKL evolution of the Pomerons together with their interactions: dissociation (one Pomeron splitting into two) and recombination (two Pomerons merging into one). It is constructed by exploiting a duality principle relating the evolutions in the target and the projectile, more precisely, splitting and merging processes, or fluctuations in the dilute regime and saturation effects in the dense regime. The simplest Pomeron loop calculated with the effective theory is free of both ultraviolet or infrared singularities. |
2203.07462 | Salvatore Rappoccio | Ben Nachman, Salvatore Rappoccio, Nhan Tran, Johan Bonilla, Grigorios
Chachamis, Barry M. Dillon, Sergei V. Chekanov, Robin Erbacher, Loukas
Gouskos, Andreas Hinzmann, Stefan H\"oche, B. Todd Huffman, Ashutosh. V.
Kotwal, Deepak Kar, Roman Kogler, Clemens Lange, Matt LeBlanc, Roy Lemmon,
Christine McLean, Mark S. Neubauer, Tilman Plehn, Debarati Roy, Giordan
Stark, Jennifer Roloff, Marcel Vos, Chih-Hsiang Yeh, Shin-Shan Yu | Jets and Jet Substructure at Future Colliders | null | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | Even though jet substructure was not an original design consideration for the
Large Hadron Collider (LHC) experiments, it has emerged as an essential tool
for the current physics program. We examine the role of jet substructure on the
motivation for and design of future energy frontier colliders. In particular,
we discuss the need for a vibrant theory and experimental research and
development program to extend jet substructure physics into the new regimes
probed by future colliders. Jet substructure has organically evolved with a
close connection between theorists and experimentalists and has catalyzed
exciting innovations in both communities. We expect such developments will play
an important role in the future energy frontier physics program.
| [
{
"created": "Mon, 14 Mar 2022 19:44:41 GMT",
"version": "v1"
}
] | 2022-03-16 | [
[
"Nachman",
"Ben",
""
],
[
"Rappoccio",
"Salvatore",
""
],
[
"Tran",
"Nhan",
""
],
[
"Bonilla",
"Johan",
""
],
[
"Chachamis",
"Grigorios",
""
],
[
"Dillon",
"Barry M.",
""
],
[
"Chekanov",
"Sergei V.",
""
],
[
"Erbacher",
"Robin",
""
],
[
"Gouskos",
"Loukas",
""
],
[
"Hinzmann",
"Andreas",
""
],
[
"Höche",
"Stefan",
""
],
[
"Huffman",
"B. Todd",
""
],
[
"Kotwal",
"Ashutosh. V.",
""
],
[
"Kar",
"Deepak",
""
],
[
"Kogler",
"Roman",
""
],
[
"Lange",
"Clemens",
""
],
[
"LeBlanc",
"Matt",
""
],
[
"Lemmon",
"Roy",
""
],
[
"McLean",
"Christine",
""
],
[
"Neubauer",
"Mark S.",
""
],
[
"Plehn",
"Tilman",
""
],
[
"Roy",
"Debarati",
""
],
[
"Stark",
"Giordan",
""
],
[
"Roloff",
"Jennifer",
""
],
[
"Vos",
"Marcel",
""
],
[
"Yeh",
"Chih-Hsiang",
""
],
[
"Yu",
"Shin-Shan",
""
]
] | Even though jet substructure was not an original design consideration for the Large Hadron Collider (LHC) experiments, it has emerged as an essential tool for the current physics program. We examine the role of jet substructure on the motivation for and design of future energy frontier colliders. In particular, we discuss the need for a vibrant theory and experimental research and development program to extend jet substructure physics into the new regimes probed by future colliders. Jet substructure has organically evolved with a close connection between theorists and experimentalists and has catalyzed exciting innovations in both communities. We expect such developments will play an important role in the future energy frontier physics program. |
0711.3755 | Frank Close Prof | T.J.Burns and F.E.Close | Hadron production in $\psi$, $\eta_c$ and $\chi$ decays | null | null | null | null | hep-ph | null | We derive relations among branching fractions in the exclusive decay of
charmonia to light flavour meson pairs assuming factorization between the quark
spin and spatial degrees of freedom. With the further assumption that these
amplitudes can be described by flux-tube models, we assess prospects for
production of hybrid mesons in charmonium decays.
| [
{
"created": "Fri, 23 Nov 2007 16:10:51 GMT",
"version": "v1"
}
] | 2007-11-26 | [
[
"Burns",
"T. J.",
""
],
[
"Close",
"F. E.",
""
]
] | We derive relations among branching fractions in the exclusive decay of charmonia to light flavour meson pairs assuming factorization between the quark spin and spatial degrees of freedom. With the further assumption that these amplitudes can be described by flux-tube models, we assess prospects for production of hybrid mesons in charmonium decays. |
1507.05478 | Zurab Berezhiani | Zurab Berezhiani | Neutron-antineutron Oscillation and Baryonic Majoron: Low Scale
Spontaneous Baryon Violation | 8 pages, 5 figures | null | 10.1140/epjc/s10052-016-4564-0 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss a possibility that baryon number $B$ is spontaneously broken at
low scales, of the order of MeV or even smaller, so that the
neutron-antineutron oscillation can be induced at the experimentally accessible
level. An associated Goldstone particle, baryonic majoron, can have observable
effects in neutron to antineutron transitions in nuclei or dense nuclear
matter. By extending baryon number to $B-L$ symmetry, baryo-majoron can be
identified with the ordinary majoron associated with the spontaneous breaking
of lepton number, with interesting implications for neutrinoless $2\beta$ becay
with the majoron emission, etc. We also discuss a hypothesis suggesting that
baryon number maybe spontaneously broken by the QCD itself via the six-quark
condensates.
| [
{
"created": "Mon, 20 Jul 2015 13:02:53 GMT",
"version": "v1"
}
] | 2017-02-01 | [
[
"Berezhiani",
"Zurab",
""
]
] | We discuss a possibility that baryon number $B$ is spontaneously broken at low scales, of the order of MeV or even smaller, so that the neutron-antineutron oscillation can be induced at the experimentally accessible level. An associated Goldstone particle, baryonic majoron, can have observable effects in neutron to antineutron transitions in nuclei or dense nuclear matter. By extending baryon number to $B-L$ symmetry, baryo-majoron can be identified with the ordinary majoron associated with the spontaneous breaking of lepton number, with interesting implications for neutrinoless $2\beta$ becay with the majoron emission, etc. We also discuss a hypothesis suggesting that baryon number maybe spontaneously broken by the QCD itself via the six-quark condensates. |
hep-ph/0306173 | Makoto Oka | Makoto Oka | Baryon-Baryon Interaction in the Quark Cluster Model | Talk presented at KEK Workshop on Few Body Physics, May 24-26, 2002 | KEK Proceedings 2002-20, pp. 18-24 | null | TIT/HEP/NP-102 | hep-ph | null | The quark cluster model approach to the baryon-baryon interaction is reviewed
and recent application to the charge symmetry breaking in nuclear force is
discussed.
| [
{
"created": "Thu, 19 Jun 2003 07:39:32 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Oka",
"Makoto",
""
]
] | The quark cluster model approach to the baryon-baryon interaction is reviewed and recent application to the charge symmetry breaking in nuclear force is discussed. |
1106.5381 | Axel Maas | Veronika Macher, Axel Maas, Reinhard Alkofer | A study of the influence of the gauge group on the Dyson-Schwinger
equations for scalar-Yang-Mills systems | 47 pages | International Journal of Modern Physics A Vol. 27, No. 18 (2012)
1250098 | 10.1142/S0217751X12500984 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The particular choice of the gauge group for Yang-Mills theory plays an
important role when it comes to the influence of matter fields. In particular,
both the chosen gauge group and the representation of the matter fields yield
structural differences in the quenched case. Especially, the qualitative
behavior of the Wilson potential is strongly dependent on this selection.
Though the algebraic reasons for this observation is clear, it is far from
obvious how this behavior can be described besides using numerical simulations.
Herein, it is investigated how the group structure appears in the
Dyson-Schwinger equations, which as a hierarchy of equations for the
correlation functions have to be satisfied. It is found that there are
differences depending on both the gauge group and the representation of the
matter fields. This provides insight into possible truncation schemes for
practical calculations using these equations.
| [
{
"created": "Mon, 27 Jun 2011 12:55:12 GMT",
"version": "v1"
}
] | 2012-07-24 | [
[
"Macher",
"Veronika",
""
],
[
"Maas",
"Axel",
""
],
[
"Alkofer",
"Reinhard",
""
]
] | The particular choice of the gauge group for Yang-Mills theory plays an important role when it comes to the influence of matter fields. In particular, both the chosen gauge group and the representation of the matter fields yield structural differences in the quenched case. Especially, the qualitative behavior of the Wilson potential is strongly dependent on this selection. Though the algebraic reasons for this observation is clear, it is far from obvious how this behavior can be described besides using numerical simulations. Herein, it is investigated how the group structure appears in the Dyson-Schwinger equations, which as a hierarchy of equations for the correlation functions have to be satisfied. It is found that there are differences depending on both the gauge group and the representation of the matter fields. This provides insight into possible truncation schemes for practical calculations using these equations. |
hep-ph/0208199 | Juan Jose Sanz Cillero | J.J. Sanz-Cillero, A. Pich (Univ. Valencia) | Rho Meson Properties in the Chiral Theory Framework | 26 pages, 8 figures, Latex file | Eur.Phys.J.C27:587-599,2003 | 10.1140/epjc/s2002-01128-8 | IFIC/02-14 | hep-ph | null | We study the mass, width and couplings of the lightest resonance multiplet
with I(J^{PC})=1(1^{--}) quantum numbers. Effective field theories based on
chiral symmetry are employed in order to describe the form factor associated
with the two-pseudoscalar matrix element of the QCD vector current. The bare
poles of the intermediate resonances are regularized through a
Dyson-Schwinger-like summation. We explore the role of the resonance width in
physical observables and make a coupled-channel analysis of final-state
interactions. This provides many interesting properties, as the pole mass
M_rho{pole}= 764.1 +- 2.7 +4.0-2.5 MeV. At energies E~1 GeV, a second 1(1^{--})
resonance multiplet is considered in order to describe the data in a more
consistent way. From the phenomenologically extracted resonance couplings, we
obtain the chiral coupling L_9^r(mu0)= (7.04 +- 0.05 +0.19-0.27)* 10^{-3}, at
mu0=770$ MeV, and show how the running with the scale mu affects the resonance
parameters. A 1/N_C counting is adopted in this work and the consistency of the
large--N_C expansion is tested. Finally, we make an estimation of the
contribution from diagrams with resonances in crossed channels.
| [
{
"created": "Thu, 22 Aug 2002 11:02:38 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Sanz-Cillero",
"J. J.",
"",
"Univ. Valencia"
],
[
"Pich",
"A.",
"",
"Univ. Valencia"
]
] | We study the mass, width and couplings of the lightest resonance multiplet with I(J^{PC})=1(1^{--}) quantum numbers. Effective field theories based on chiral symmetry are employed in order to describe the form factor associated with the two-pseudoscalar matrix element of the QCD vector current. The bare poles of the intermediate resonances are regularized through a Dyson-Schwinger-like summation. We explore the role of the resonance width in physical observables and make a coupled-channel analysis of final-state interactions. This provides many interesting properties, as the pole mass M_rho{pole}= 764.1 +- 2.7 +4.0-2.5 MeV. At energies E~1 GeV, a second 1(1^{--}) resonance multiplet is considered in order to describe the data in a more consistent way. From the phenomenologically extracted resonance couplings, we obtain the chiral coupling L_9^r(mu0)= (7.04 +- 0.05 +0.19-0.27)* 10^{-3}, at mu0=770$ MeV, and show how the running with the scale mu affects the resonance parameters. A 1/N_C counting is adopted in this work and the consistency of the large--N_C expansion is tested. Finally, we make an estimation of the contribution from diagrams with resonances in crossed channels. |
hep-ph/0311071 | C. Hanhart | A. Gillitzer, C. Hanhart, V. Kleber, S. Krewald, H.P. Morsch, F.
Rathmann, A. Sibirtsev | Hadron Physics at COSY | Miniproceedings for the workshop 'Hadron Physics at COSY' held from
July 7th to July 10th 2003 in Bad Honnef; 161 pages, 10 figures | null | null | null | hep-ph nucl-th | null | The workshop 'Hadron Physics at COSY' held from July 7th to July 10th 2003 in
Bad Honnef brought together experimentalists and theoreticians from various
fields of hadron physics to identify the key physics questions, which can be
addressed with (un-) polarized proton and deuteron induced reactions at COSY.
Topics discussed include charge symmetry breaking, elastic and inelastic
nucleon-nucleon and nucleon-deuteron interactions, hadrons in the medium,
mesonic bound states, meson and baryon resonances, and the hyperon-nucleon
system. In addition prospects of the planned GSI facility were discussed. These
Miniproceedings contain besides short summaries of the presentations the most
relevant references for the field.
| [
{
"created": "Thu, 6 Nov 2003 08:37:27 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Gillitzer",
"A.",
""
],
[
"Hanhart",
"C.",
""
],
[
"Kleber",
"V.",
""
],
[
"Krewald",
"S.",
""
],
[
"Morsch",
"H. P.",
""
],
[
"Rathmann",
"F.",
""
],
[
"Sibirtsev",
"A.",
""
]
] | The workshop 'Hadron Physics at COSY' held from July 7th to July 10th 2003 in Bad Honnef brought together experimentalists and theoreticians from various fields of hadron physics to identify the key physics questions, which can be addressed with (un-) polarized proton and deuteron induced reactions at COSY. Topics discussed include charge symmetry breaking, elastic and inelastic nucleon-nucleon and nucleon-deuteron interactions, hadrons in the medium, mesonic bound states, meson and baryon resonances, and the hyperon-nucleon system. In addition prospects of the planned GSI facility were discussed. These Miniproceedings contain besides short summaries of the presentations the most relevant references for the field. |
2312.11386 | Roger Balsach | Roger Balsach, Domenico Bonocore and Anna Kulesza | Soft-photon spectra and the LBK theorem | 37 pages, 6 figures, 1 table | null | null | MS-TP-23-47, TUM-HEP-1486-23 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The study of next-to-leading-power (NLP) corrections in soft emissions
continues to attract interest both in QCD and in QED. Soft-photon spectra in
particular provide a clean case-study for the experimental verification of the
Low-Burnett-Kroll (LBK) theorem. In this paper we study the consistency of the
LBK theorem in the context of an ambiguity arising from momentum-conservation
constraints in the computation of non-radiative amplitudes. We clarify that
this ambiguity leads to various possible formulations of the LBK theorem, which
are all equivalent up to power-suppressed effects (i.e. beyond the formal
accuracy of the LBK theorem). We also propose a new formulation of the LBK
theorem with a modified shifted kinematics which facilitates the numerical
computation of non-radiative amplitudes with publicly available tools.
Furthermore, we present numerical results for soft-photon spectra in the
associated production of a muon pair with a photon, both in $e^+e^-$
annihilation and proton-proton collisions.
| [
{
"created": "Mon, 18 Dec 2023 17:51:09 GMT",
"version": "v1"
}
] | 2023-12-19 | [
[
"Balsach",
"Roger",
""
],
[
"Bonocore",
"Domenico",
""
],
[
"Kulesza",
"Anna",
""
]
] | The study of next-to-leading-power (NLP) corrections in soft emissions continues to attract interest both in QCD and in QED. Soft-photon spectra in particular provide a clean case-study for the experimental verification of the Low-Burnett-Kroll (LBK) theorem. In this paper we study the consistency of the LBK theorem in the context of an ambiguity arising from momentum-conservation constraints in the computation of non-radiative amplitudes. We clarify that this ambiguity leads to various possible formulations of the LBK theorem, which are all equivalent up to power-suppressed effects (i.e. beyond the formal accuracy of the LBK theorem). We also propose a new formulation of the LBK theorem with a modified shifted kinematics which facilitates the numerical computation of non-radiative amplitudes with publicly available tools. Furthermore, we present numerical results for soft-photon spectra in the associated production of a muon pair with a photon, both in $e^+e^-$ annihilation and proton-proton collisions. |
1911.05092 | Dennis Schr\"oder | Dietrich Bodeker and Dennis Schroder | Kinetic equations for sterile neutrinos from thermal fluctuations | 30 pages. v2: Typos corrected, results unchanged, published version | JCAP02(2020)033 | 10.1088/1475-7516/2020/02/033 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We obtain non-linear kinetic equations for sterile neutrino occupancies and
lepton minus baryon numbers by matching real time correlation functions of
thermal fluctuations computed in an effective description to those computed in
thermal quantum field theory. After expanding in the sterile-neutrino Yukawa
couplings, the coefficients in the equations are written as real time
correlation functions of Standard Model operators. Our kinetic equations are
valid for an arbitrary number of sterile neutrinos of any mass spectrum. They
can be used to describe, e.g., low-scale leptogenesis via neutrino
oscillations, or sterile neutrino dark matter production in the Higgs phase.
| [
{
"created": "Tue, 12 Nov 2019 19:00:05 GMT",
"version": "v1"
},
{
"created": "Thu, 27 Feb 2020 17:10:54 GMT",
"version": "v2"
}
] | 2020-02-28 | [
[
"Bodeker",
"Dietrich",
""
],
[
"Schroder",
"Dennis",
""
]
] | We obtain non-linear kinetic equations for sterile neutrino occupancies and lepton minus baryon numbers by matching real time correlation functions of thermal fluctuations computed in an effective description to those computed in thermal quantum field theory. After expanding in the sterile-neutrino Yukawa couplings, the coefficients in the equations are written as real time correlation functions of Standard Model operators. Our kinetic equations are valid for an arbitrary number of sterile neutrinos of any mass spectrum. They can be used to describe, e.g., low-scale leptogenesis via neutrino oscillations, or sterile neutrino dark matter production in the Higgs phase. |
0901.1870 | Brett D. Altschul | Brett Altschul | Disentangling Forms of Lorentz Violation With Complementary Clock
Comparison Experiments | 9 pages | Phys.Rev.D79:061702,2009 | 10.1103/PhysRevD.79.061702 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Atomic clock comparisons provide some of the most precise tests of Lorentz
and CPT symmetries in the laboratory. With data from multiple such experiments
using different nuclei, it is possible to constrain new regions of the
parameter space for Lorentz violation. Relativistic effects in the nuclei allow
us to disentangle forms of Lorentz violation which could not be separately
measured in purely nonrelativistic experiments. The disentangled bounds in the
neutron sectors are at the 10^(-28) GeV level, far better than could be
obtained with any other current technique.
| [
{
"created": "Tue, 13 Jan 2009 20:13:43 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Jan 2009 18:13:39 GMT",
"version": "v2"
}
] | 2014-11-18 | [
[
"Altschul",
"Brett",
""
]
] | Atomic clock comparisons provide some of the most precise tests of Lorentz and CPT symmetries in the laboratory. With data from multiple such experiments using different nuclei, it is possible to constrain new regions of the parameter space for Lorentz violation. Relativistic effects in the nuclei allow us to disentangle forms of Lorentz violation which could not be separately measured in purely nonrelativistic experiments. The disentangled bounds in the neutron sectors are at the 10^(-28) GeV level, far better than could be obtained with any other current technique. |
1906.11795 | Anton Rebhan | Josef Leutgeb, Jonas Mager, Anton Rebhan | Pseudoscalar transition form factors and the hadronic light-by-light
contribution to the anomalous magnetic moment of the muon from holographic
QCD | 19 pages, 5 figures, 2 tables; v3: detailed comparison with
dispersive approach added, one more figure and several more references; v4:
typo in acknowledgments fixed; v5: extended discussion of eta' contribution
(version to appear in PRD); v6: corrected $a_\mu$ results for the HW1 model
(erratum to appear in PRD), which improves agreement with dispersive results
- figures unaffected | Phys. Rev. D 100, 094038 (2019) | 10.1103/PhysRevD.100.094038 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit the predictions for the pseudoscalar-photon transition form
factors in bottom-up and top-down holographic QCD models which only use the
pion decay constant and the $\rho$ meson mass as input. We find remarkable
agreement with the available experimental data for the single-virtual $\pi^0$
form factor that have recently been extended to lower momenta by BESIII, down
to 0.3 GeV$^2$. The bottom-up models moreover turn out to be roughly consistent
with recent experimental results obtained by BaBar for the double-virtual
$\eta'$ form factor at large momenta as well as with a recent lattice
extrapolation for the double-virtual $\pi^0$ form factor. Calculating the pion
pole contribution to the hadronic light-by-light scattering in the anomalous
magnetic moment of the muon, we find that the bottom-up models in question span
the range $a_\mu^{\pi^0}=6.1(4)\cdot 10^{-10}, which is somewhat lower than
estimated previously by approximating these holographic predictions through
simple interpolators, and in remarkably good agreement with recent results
based on a dispersive approach or lattice simulations.
| [
{
"created": "Thu, 27 Jun 2019 16:56:50 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Jul 2019 17:58:44 GMT",
"version": "v2"
},
{
"created": "Mon, 7 Oct 2019 17:48:29 GMT",
"version": "v3"
},
{
"created": "Wed, 16 Oct 2019 16:24:56 GMT",
"version": "v4"
},
{
"created": "Wed, 30 Oct 2019 19:47:22 GMT",
"version": "v5"
},
{
"created": "Tue, 17 Aug 2021 13:30:46 GMT",
"version": "v6"
}
] | 2021-08-18 | [
[
"Leutgeb",
"Josef",
""
],
[
"Mager",
"Jonas",
""
],
[
"Rebhan",
"Anton",
""
]
] | We revisit the predictions for the pseudoscalar-photon transition form factors in bottom-up and top-down holographic QCD models which only use the pion decay constant and the $\rho$ meson mass as input. We find remarkable agreement with the available experimental data for the single-virtual $\pi^0$ form factor that have recently been extended to lower momenta by BESIII, down to 0.3 GeV$^2$. The bottom-up models moreover turn out to be roughly consistent with recent experimental results obtained by BaBar for the double-virtual $\eta'$ form factor at large momenta as well as with a recent lattice extrapolation for the double-virtual $\pi^0$ form factor. Calculating the pion pole contribution to the hadronic light-by-light scattering in the anomalous magnetic moment of the muon, we find that the bottom-up models in question span the range $a_\mu^{\pi^0}=6.1(4)\cdot 10^{-10}, which is somewhat lower than estimated previously by approximating these holographic predictions through simple interpolators, and in remarkably good agreement with recent results based on a dispersive approach or lattice simulations. |
1808.01952 | Ismail Zahed | Kiminad A. Mamo and Ismail Zahed | Deep Inelastic Scattering on a Nucleus using Holography | 6 pages, 2 figures | Phys. Rev. D 100, 046015 (2019) | 10.1103/PhysRevD.100.046015 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider deep inelastic scattering (DIS) on a nucleus described using a
density expansion. In leading order, the scattering is dominated by the
incoherent scattering on individual nucleons distributed using the Thomas-Fermi
approximation. We use the holographic structure functions for DIS scattering on
single nucleons to make a non-perturbative estimate of the nuclear structure
function in leading order in the density. Our results are compared to the data
in the large-x regime.
| [
{
"created": "Mon, 6 Aug 2018 15:01:24 GMT",
"version": "v1"
}
] | 2019-08-28 | [
[
"Mamo",
"Kiminad A.",
""
],
[
"Zahed",
"Ismail",
""
]
] | We consider deep inelastic scattering (DIS) on a nucleus described using a density expansion. In leading order, the scattering is dominated by the incoherent scattering on individual nucleons distributed using the Thomas-Fermi approximation. We use the holographic structure functions for DIS scattering on single nucleons to make a non-perturbative estimate of the nuclear structure function in leading order in the density. Our results are compared to the data in the large-x regime. |
hep-ph/0203181 | Subhendra Mohanty | Anjan S. Joshipura, Eduard Masso and Subhendra Mohanty | Constraints on decay plus oscillation solutions of the solar neutrino
problem | 8 pages latex file with 4 figures | Phys.Rev.D66:113008,2002 | 10.1103/PhysRevD.66.113008 | null | hep-ph | null | We examine the constraints on non-radiative decay of neutrinos from the
observations of solar neutrino experiments. The standard oscillation hypothesis
among three neutrinos solves the solar and atmospheric neutrino problems. Decay
of a massive neutrino mixed with the electron neutrino results in the depletion
of the solar neutrino flux. We introduce neutrino decay in the oscillation
hypothesis and demand that decay does not spoil the successful explanation of
solar and atmospheric observations. We obtain a lower bound on the ratio of the
lifetime over the mass of $\nu_2$, $(\tau_2/m_2) > 22.7 (\srm/\MeV)$ for the
MSW solution of the solar neutrino problem and $(\tau_2/m_2) > 27.8
(\srm/\MeV)$ for the VO solution (at 99% C.L.).
| [
{
"created": "Tue, 19 Mar 2002 09:34:40 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Joshipura",
"Anjan S.",
""
],
[
"Masso",
"Eduard",
""
],
[
"Mohanty",
"Subhendra",
""
]
] | We examine the constraints on non-radiative decay of neutrinos from the observations of solar neutrino experiments. The standard oscillation hypothesis among three neutrinos solves the solar and atmospheric neutrino problems. Decay of a massive neutrino mixed with the electron neutrino results in the depletion of the solar neutrino flux. We introduce neutrino decay in the oscillation hypothesis and demand that decay does not spoil the successful explanation of solar and atmospheric observations. We obtain a lower bound on the ratio of the lifetime over the mass of $\nu_2$, $(\tau_2/m_2) > 22.7 (\srm/\MeV)$ for the MSW solution of the solar neutrino problem and $(\tau_2/m_2) > 27.8 (\srm/\MeV)$ for the VO solution (at 99% C.L.). |
hep-ph/9312343 | Harada Masayasu | Masako Bando, Masayasu Harada and Taichiro Kugo | External Gauge Invariance and Anomaly in BS Vertices and Boundstates | 30 pages, plain TeX (using `phyzzx' macro), 17 Postscript Figures are
included as uuencoded files (need `epsf.tex'), KUNS-1236, HE(TH) 93/13 | Prog.Theor.Phys. 91 (1994) 927-948 | 10.1143/ptp/91.5.927 | null | hep-ph | null | A systematic method is given for obtaining consistent approximations to the
Schwinger-Dyson(SD) and Bethe-Salpeter(BS) equations which maintain the
external gauge invariance. We show that for any order of approximation to the
SD equation there is a corresponding approximation to the BS equations such
that the solutions to those equations satisfy the Ward-Takahashi identities of
the external gauge symmetry. This formulation also clarifies the way how we can
calculate the Green functions of current operators in a consistent manner with
the gauge invariance and the axial anomaly. We show which type of diagrams for
the $\pi^0\rightarrow\gamma\gamma$ amplitude using the pion BS amplitude give
result consistent with the low-energy theorem. An interesting phenomenon is
observed in the ladder approximation that the low energy theorem is saturated
by the zeroth order terms in the external momenta of the pseudoscalar BS
amplitude and the vector vertex functions.
| [
{
"created": "Mon, 27 Dec 1993 11:43:41 GMT",
"version": "v1"
}
] | 2017-02-01 | [
[
"Bando",
"Masako",
""
],
[
"Harada",
"Masayasu",
""
],
[
"Kugo",
"Taichiro",
""
]
] | A systematic method is given for obtaining consistent approximations to the Schwinger-Dyson(SD) and Bethe-Salpeter(BS) equations which maintain the external gauge invariance. We show that for any order of approximation to the SD equation there is a corresponding approximation to the BS equations such that the solutions to those equations satisfy the Ward-Takahashi identities of the external gauge symmetry. This formulation also clarifies the way how we can calculate the Green functions of current operators in a consistent manner with the gauge invariance and the axial anomaly. We show which type of diagrams for the $\pi^0\rightarrow\gamma\gamma$ amplitude using the pion BS amplitude give result consistent with the low-energy theorem. An interesting phenomenon is observed in the ladder approximation that the low energy theorem is saturated by the zeroth order terms in the external momenta of the pseudoscalar BS amplitude and the vector vertex functions. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.