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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/9809447
|
Stephen Wong
|
S.M.H. Wong
|
Colour octet contribution to exclusive P-wave charmonium decay into
nucleon-antinucleon
|
espcrc2 style, talk presented at QCD'98, July 1998, Montpellier,
France
|
Nucl.Phys.Proc.Suppl. 74 (1999) 231
|
10.1016/S0920-5632(99)00169-3
|
IASA 98-2, UA/NPPS-98-12
|
hep-ph
| null |
We show that although there is no infrared divergence in exclusive P-wave
quarkonium decays, the colour octet contribution is no less important than in
the inclusive decay. Results from more proper calculations with only colour
singlet contribution are not sufficient to account for the measured partial
decay widths and so the next higher Fock state must be included. Using the
$\c_J$ decay into $N\bar N$ as an example, a scheme is devised to yield
estimates of the decay widths using both contributions, the results are
comparable with experimental measurements.
|
[
{
"created": "Fri, 18 Sep 1998 10:56:38 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Wong",
"S. M. H.",
""
]
] |
We show that although there is no infrared divergence in exclusive P-wave quarkonium decays, the colour octet contribution is no less important than in the inclusive decay. Results from more proper calculations with only colour singlet contribution are not sufficient to account for the measured partial decay widths and so the next higher Fock state must be included. Using the $\c_J$ decay into $N\bar N$ as an example, a scheme is devised to yield estimates of the decay widths using both contributions, the results are comparable with experimental measurements.
|
1811.02261
|
Liaoshan Shi
|
Liaoshan Shi, Zhijun Liang, Bo Liu, Zhenhui He
|
Constraining the anomalous Higgs boson coupling in $H$+$\gamma$
production
|
10 pages, 3 figures
|
Chinese Physics C Vol. 43, No. 4 (2019) 043001
|
10.1088/1674-1137/43/4/043001
| null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
Higgs boson production in association with a photon ($H$+$\gamma$) offers a
promising channel to test the Higgs boson to photon coupling at various energy
scales. Its potential sensitivity to anomalous couplings of the Higgs boson has
not been explored with the proton-proton collision data. In this paper, we
reinterpret the latest ATLAS $H$+$\gamma$ resonance search results within the
Standard Model effective field theory (EFT) framework, using 36.1 fb$^{-1}$ of
proton-proton collision data recorded with the ATLAS detector at $\sqrt{s}=13$
TeV. Constraints on the Wilson coefficients of dimension-six EFT operators
related to the Higgs boson to photon coupling are provided for the first time
in the $H$+$\gamma$ final state at the LHC.
|
[
{
"created": "Tue, 6 Nov 2018 09:52:29 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Jan 2019 04:19:56 GMT",
"version": "v2"
},
{
"created": "Mon, 18 Mar 2019 12:55:58 GMT",
"version": "v3"
}
] |
2019-03-19
|
[
[
"Shi",
"Liaoshan",
""
],
[
"Liang",
"Zhijun",
""
],
[
"Liu",
"Bo",
""
],
[
"He",
"Zhenhui",
""
]
] |
Higgs boson production in association with a photon ($H$+$\gamma$) offers a promising channel to test the Higgs boson to photon coupling at various energy scales. Its potential sensitivity to anomalous couplings of the Higgs boson has not been explored with the proton-proton collision data. In this paper, we reinterpret the latest ATLAS $H$+$\gamma$ resonance search results within the Standard Model effective field theory (EFT) framework, using 36.1 fb$^{-1}$ of proton-proton collision data recorded with the ATLAS detector at $\sqrt{s}=13$ TeV. Constraints on the Wilson coefficients of dimension-six EFT operators related to the Higgs boson to photon coupling are provided for the first time in the $H$+$\gamma$ final state at the LHC.
|
1705.11088
|
Bernard Pire
|
B. Pire, L. Szymanowski, J. Wagner
|
Hard exclusive neutrino production of a light meson
|
9 pages, 8 figures. second version (to be published in Phys Rev D):
misprint in name of second author corrected; one added reference; minor
misprints corrected. arXiv admin note: text overlap with arXiv:1702.00316
|
Phys. Rev. D 95, 114029 (2017)
|
10.1103/PhysRevD.95.114029
|
CPHT-RR033.052017
|
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We update the leading order in $\alpha_s$ QCD amplitude for deep exclusive
neutrino and antineutrino production of a light meson on an unpolarized
nucleon. The factorization theorems of the collinear QCD approach allow us to
write the amplitude as the convolution of generalized parton distributions
(GPDs) and perturbatively calculable coefficient functions. We study both the
pseudoscalar meson and longitudinally polarized vector meson cases. It turns
out that, contrarily to the electroproduction case, the leading twist
scattering amplitudes for $\pi$ and $\rho_L$ productions are proportional to
one another, which may serve as an interesting new test of the leading twist
dominance of exclusive processes at medium scale. The dominance of the gluonic
contribution to most cross sections is stressed.
|
[
{
"created": "Tue, 30 May 2017 07:15:52 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Jun 2017 08:08:02 GMT",
"version": "v2"
}
] |
2017-07-05
|
[
[
"Pire",
"B.",
""
],
[
"Szymanowski",
"L.",
""
],
[
"Wagner",
"J.",
""
]
] |
We update the leading order in $\alpha_s$ QCD amplitude for deep exclusive neutrino and antineutrino production of a light meson on an unpolarized nucleon. The factorization theorems of the collinear QCD approach allow us to write the amplitude as the convolution of generalized parton distributions (GPDs) and perturbatively calculable coefficient functions. We study both the pseudoscalar meson and longitudinally polarized vector meson cases. It turns out that, contrarily to the electroproduction case, the leading twist scattering amplitudes for $\pi$ and $\rho_L$ productions are proportional to one another, which may serve as an interesting new test of the leading twist dominance of exclusive processes at medium scale. The dominance of the gluonic contribution to most cross sections is stressed.
|
hep-ph/0112059
|
Michael R. Douglas
|
T. Banks (Rutgers and UCSC), M. Dine (UCSC) and M. R. Douglas (Rutgers
and IHES)
|
Time-Varying alpha and Particle Physics
|
7 pages, latex, JHEP.cls
|
Phys.Rev.Lett. 88 (2002) 131301
|
10.1103/PhysRevLett.88.131301
| null |
hep-ph astro-ph hep-th
| null |
We argue that models in which an observable variation of the fine structure
constant is explained by motion of a cosmic scalar field, are not stable under
renormalization, and require massive fine tuning that cannot be explained by
any known mechanism.
|
[
{
"created": "Tue, 4 Dec 2001 19:35:50 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Jan 2002 15:28:47 GMT",
"version": "v2"
},
{
"created": "Wed, 9 Jan 2002 20:54:10 GMT",
"version": "v3"
}
] |
2009-11-07
|
[
[
"Banks",
"T.",
"",
"Rutgers and UCSC"
],
[
"Dine",
"M.",
"",
"UCSC"
],
[
"Douglas",
"M. R.",
"",
"Rutgers\n and IHES"
]
] |
We argue that models in which an observable variation of the fine structure constant is explained by motion of a cosmic scalar field, are not stable under renormalization, and require massive fine tuning that cannot be explained by any known mechanism.
|
1812.06963
|
Monika Blanke
|
Monika Blanke, Andrzej J. Buras
|
Emerging $\Delta M_{d}$-Anomaly from Tree-Level Determinations of
$|V_{cb}|$ and the Angle $\gamma$
|
15 pages, 8 figures, 3 tables. v2: Clarifying comments and one figure
added, conclusions unchanged. Matches published version
|
Eur. Phys. J. C 79 (2019) 159
|
10.1140/epjc/s10052-019-6667-x
|
TTP18-044, AJB-18-10
|
hep-ph hep-ex hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We point out that the recently increased value of the angle $\gamma$ in the
Unitarity Triangle (UT), determined in tree-level decays to be
$\gamma=(74.0^{+5.0}_{-5.8})^\circ$ by the LHCb collaboration, combined with
the most recent value of $|V_{cb}|$ implies an enhancement of $\Delta M_{d}$
over the data in the ballpark of $30\%$. This is roughly by a factor of two
larger than the enhancement of $\Delta M_{s}$ that is independent of $\gamma$.
This disparity of enhancements is problematic for models with Constrained
Minimal Flavour Violation (CMFV) and also for $U(2)^3$ models. In view of the
prospects of measuring $\gamma$ with the precision of $\pm 1^\circ$ by Belle II
and LHCb in the coming years, we propose to use the angles $\gamma$ and $\beta$
together with $|V_{cb}|$ and $|V_{us}|$ as the fundamental parameters of the
CKM matrix until $|V_{ub}|$ from tree-level decays will be known precisely.
Displaying $\Delta M_{s,d}$ as functions of $\gamma$ clearly demonstrates the
tension between the value of $\gamma$ from tree-level decays, free from new
physics (NP) contributions, and $\Delta M_{s,d}$ calculated in CMFV and
$U(2)^3$ models and thus exhibits the presence of NP contributions to $\Delta
M_{s,d}$ beyond these frameworks. We calculate the values of $|V_{ub}|$ and
$|V_{td}|$ as functions of $\gamma$ and $|V_{cb}|$ and discuss the implications
of our results for $\varepsilon_K$ and rare $K$ and $B$ decays. We also briefly
discuss a future strategy in which $\beta$, possibly affected by NP, is
replaced by $|V_{ub}|$.
|
[
{
"created": "Mon, 17 Dec 2018 18:59:59 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Feb 2019 10:04:28 GMT",
"version": "v2"
}
] |
2019-02-27
|
[
[
"Blanke",
"Monika",
""
],
[
"Buras",
"Andrzej J.",
""
]
] |
We point out that the recently increased value of the angle $\gamma$ in the Unitarity Triangle (UT), determined in tree-level decays to be $\gamma=(74.0^{+5.0}_{-5.8})^\circ$ by the LHCb collaboration, combined with the most recent value of $|V_{cb}|$ implies an enhancement of $\Delta M_{d}$ over the data in the ballpark of $30\%$. This is roughly by a factor of two larger than the enhancement of $\Delta M_{s}$ that is independent of $\gamma$. This disparity of enhancements is problematic for models with Constrained Minimal Flavour Violation (CMFV) and also for $U(2)^3$ models. In view of the prospects of measuring $\gamma$ with the precision of $\pm 1^\circ$ by Belle II and LHCb in the coming years, we propose to use the angles $\gamma$ and $\beta$ together with $|V_{cb}|$ and $|V_{us}|$ as the fundamental parameters of the CKM matrix until $|V_{ub}|$ from tree-level decays will be known precisely. Displaying $\Delta M_{s,d}$ as functions of $\gamma$ clearly demonstrates the tension between the value of $\gamma$ from tree-level decays, free from new physics (NP) contributions, and $\Delta M_{s,d}$ calculated in CMFV and $U(2)^3$ models and thus exhibits the presence of NP contributions to $\Delta M_{s,d}$ beyond these frameworks. We calculate the values of $|V_{ub}|$ and $|V_{td}|$ as functions of $\gamma$ and $|V_{cb}|$ and discuss the implications of our results for $\varepsilon_K$ and rare $K$ and $B$ decays. We also briefly discuss a future strategy in which $\beta$, possibly affected by NP, is replaced by $|V_{ub}|$.
|
1301.1123
|
Kazunori Nakayama
|
Masahiro Kawasaki, Kazunori Nakayama
|
Axions : Theory and Cosmological Role
|
43 pages, 10 figures; invited review submitted to
Ann.Rev.Part.Nucl.Sci
| null |
10.1146/annurev-nucl-102212-170536
|
ICRR-Report-643-2012-32, IPMU13-0009, UT-13-01
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We review recent developments on axion cosmology. Topics include : axion cold
dark matter, axions from topological defects, axion isocurvature perturbation
and its non-Gaussianity and axino/saxion cosmology in supersymmetric axion
model.
|
[
{
"created": "Mon, 7 Jan 2013 07:47:42 GMT",
"version": "v1"
}
] |
2015-06-12
|
[
[
"Kawasaki",
"Masahiro",
""
],
[
"Nakayama",
"Kazunori",
""
]
] |
We review recent developments on axion cosmology. Topics include : axion cold dark matter, axions from topological defects, axion isocurvature perturbation and its non-Gaussianity and axino/saxion cosmology in supersymmetric axion model.
|
hep-ph/9805426
|
Dr. Athanasios Dedes
|
A. Dedes, A.B. Lahanas and K. Tamvakis
|
Z-Observables and the Effective Weak Mixing Angle in the MSSM
|
6 pages, 5 figures, Talk presented by A. Dedes at the International
Workshop of the Hellenic Society for the Study of High-Energy Physics,
Athens, Greece, 9-11 Apr 1998
| null | null | null |
hep-ph
| null |
We make a comparison of the predicted effective weak mixing angle, the Z-on
resonance asymmetries and the W-boson mass to the LEP and SLD data at their
present status. We find that the predicted MSSM values for the effective weak
mixing angle are in agreement with the LEP+SLD average value for a ``heavy''
SUSY breaking scale while we observe an agreement with SLD data in the case of
a ``light'' SUSY breaking scale. The resulting values for the W-boson mass and
for the electron left-right asymmetries are compatible with CDF,UA2,DO and LEP
data respectively. Unexpectedly we find that the supersymmetric QCD
contributions to the Z-observables tend to vanish everywhere in the M1/2-M0
plane. Furthermore, values of M1/2 which are greater than 500 GeV are favoured
by the MSSM if one considers the current experimental value for the strong
coupling.
|
[
{
"created": "Fri, 22 May 1998 15:32:07 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Dedes",
"A.",
""
],
[
"Lahanas",
"A. B.",
""
],
[
"Tamvakis",
"K.",
""
]
] |
We make a comparison of the predicted effective weak mixing angle, the Z-on resonance asymmetries and the W-boson mass to the LEP and SLD data at their present status. We find that the predicted MSSM values for the effective weak mixing angle are in agreement with the LEP+SLD average value for a ``heavy'' SUSY breaking scale while we observe an agreement with SLD data in the case of a ``light'' SUSY breaking scale. The resulting values for the W-boson mass and for the electron left-right asymmetries are compatible with CDF,UA2,DO and LEP data respectively. Unexpectedly we find that the supersymmetric QCD contributions to the Z-observables tend to vanish everywhere in the M1/2-M0 plane. Furthermore, values of M1/2 which are greater than 500 GeV are favoured by the MSSM if one considers the current experimental value for the strong coupling.
|
1306.5384
|
Dremin
|
I.M. Dremin, V.A. Nechitailo
|
Proton periphery activated by multiparticle dynamics
|
9 pages, 4 figures
| null |
10.1016/j.nuclphysa.2013.08.009
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
It is shown that protons become more active at the periphery with increase of
their collision energy. By computing the impact parameter distribution of the
proton-proton overlap function at LHC energies and comparing it with ISR (and
S$p\bar p$S for $p\bar p$) data, we conclude that the peripheral region of
protons plays an increasing role in the rise of total cross sections through
multiparticle dynamics. The size of the proton as well as its blackness
increase with energy. The protons become more black both in the central region
and, especially, at the periphery. This effect can be related to the ridge
phenomenon and to the inelastic diffraction processes at LHC energies.
|
[
{
"created": "Sun, 23 Jun 2013 08:00:50 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Sep 2013 08:34:23 GMT",
"version": "v2"
}
] |
2015-06-16
|
[
[
"Dremin",
"I. M.",
""
],
[
"Nechitailo",
"V. A.",
""
]
] |
It is shown that protons become more active at the periphery with increase of their collision energy. By computing the impact parameter distribution of the proton-proton overlap function at LHC energies and comparing it with ISR (and S$p\bar p$S for $p\bar p$) data, we conclude that the peripheral region of protons plays an increasing role in the rise of total cross sections through multiparticle dynamics. The size of the proton as well as its blackness increase with energy. The protons become more black both in the central region and, especially, at the periphery. This effect can be related to the ridge phenomenon and to the inelastic diffraction processes at LHC energies.
|
hep-ph/9806231
| null |
Benedikt Lehmann-Dronke, Andreas Sch\"afer
|
IR-Renormalon Contributions to the Structure Functions $g_3$ and $g_5$
|
12 pages, 4 eps-figures
|
Eur.Phys.J. A4 (1999) 97-102
|
10.1007/s100500050208
| null |
hep-ph
| null |
We calculate the leading $1/N_f$ perturbative contributions to the polarized
nonsinglet structure functions $g_3$ and $g_5$ to all orders in $\alpha_s$. The
contributions from the first renormalon pole are determined. It is a measure
for the ambiguity of the perturbative calculation and is assumed to dominate
the power corrections. The corrections $\Delta g_3$ and $\Delta g_5$ are given
as functions of the Bjorken variable $x$ and turn out to be negligable. The
anomalous dimensions of the leading twist operators are obtained in the
next-to-leading order.
|
[
{
"created": "Tue, 2 Jun 1998 14:30:43 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Lehmann-Dronke",
"Benedikt",
""
],
[
"Schäfer",
"Andreas",
""
]
] |
We calculate the leading $1/N_f$ perturbative contributions to the polarized nonsinglet structure functions $g_3$ and $g_5$ to all orders in $\alpha_s$. The contributions from the first renormalon pole are determined. It is a measure for the ambiguity of the perturbative calculation and is assumed to dominate the power corrections. The corrections $\Delta g_3$ and $\Delta g_5$ are given as functions of the Bjorken variable $x$ and turn out to be negligable. The anomalous dimensions of the leading twist operators are obtained in the next-to-leading order.
|
1805.06281
|
Nasuf Sonmez PhD
|
Nasuf Sonmez
|
Pair production of the lightest chargino at $\gamma\gamma$-collider
|
14 pages, 12 figures
| null |
10.1016/j.nuclphysb.2018.12.019
|
17-FEN-054
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Chargino pair production via photon-photon collision is investigated in the
Minimal Supersymmetric Standard Model at a future linear collider. The process
is computed using all the possible diagrams at the next-to-leading order,
including box, triangle, and self-energy diagrams. The numerical analysis is
carried out for the production rates of the lightest chargino pair in RNS, NS,
mSUGRA, BB, and NUGM scenarios. These distinct benchmark models were introduced
in the light of the LHC results presented at $\sqrt{s}=7-8\text{ TeV}$. Among
these scenarios, the RNS has the highest production rate for the
$\gamma\gamma\rightarrow \tilde\chi_1^+ \tilde\chi_1^-$. The partonic cross
section reaches up to $3.94\text{ pb}$ at $\sqrt{\hat{s}}=310\text{ GeV}$. The
total convoluted cross section with the photon luminosity in a $e^+e^-$ machine
is calculated as a function of the center-of-mass energy up to $1\text{ TeV}$.
The convoluted cross section is $\sim1.05\text{ pb}$ at $\sqrt{s}=350\text{
GeV}$ depending on the polarization of the initial electron and laser
polarization. The RNS along with the BB scenarios are accessible at
$\sqrt{s}=500\text{ GeV}$ with a $\gamma\gamma$ collision mode on
$e^+e^-$-collider.
|
[
{
"created": "Wed, 16 May 2018 13:03:34 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Oct 2018 12:18:38 GMT",
"version": "v2"
},
{
"created": "Wed, 2 Jan 2019 16:32:52 GMT",
"version": "v3"
}
] |
2019-01-03
|
[
[
"Sonmez",
"Nasuf",
""
]
] |
Chargino pair production via photon-photon collision is investigated in the Minimal Supersymmetric Standard Model at a future linear collider. The process is computed using all the possible diagrams at the next-to-leading order, including box, triangle, and self-energy diagrams. The numerical analysis is carried out for the production rates of the lightest chargino pair in RNS, NS, mSUGRA, BB, and NUGM scenarios. These distinct benchmark models were introduced in the light of the LHC results presented at $\sqrt{s}=7-8\text{ TeV}$. Among these scenarios, the RNS has the highest production rate for the $\gamma\gamma\rightarrow \tilde\chi_1^+ \tilde\chi_1^-$. The partonic cross section reaches up to $3.94\text{ pb}$ at $\sqrt{\hat{s}}=310\text{ GeV}$. The total convoluted cross section with the photon luminosity in a $e^+e^-$ machine is calculated as a function of the center-of-mass energy up to $1\text{ TeV}$. The convoluted cross section is $\sim1.05\text{ pb}$ at $\sqrt{s}=350\text{ GeV}$ depending on the polarization of the initial electron and laser polarization. The RNS along with the BB scenarios are accessible at $\sqrt{s}=500\text{ GeV}$ with a $\gamma\gamma$ collision mode on $e^+e^-$-collider.
|
1408.0660
|
Shunzo Kumano
|
M. Hirai, S. Kumano, K. Saito, T. Watanabe
|
Clustering structure of nuclei in deep inelastic processes
|
5 pages, 7 figures, to be published in Proceedings of IOP Conference
Series, 3rd International Workshop on State of the Art in Nuclear Cluster
Physics, Kanto Gakuin University, Yokohama, Japan, May 26-30, 2014
| null |
10.1088/1742-6596/569/1/012021
|
KEK-TH-1757, J-PARC-TH-0040
|
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A clustering aspect is explained for the $^9$Be nucleus in charged-lepton
deep inelastic scattering. Nuclear modifications of the structure function
$F_2$ are studied by the ratio $R_{\rm EMC} = F_2^A /F_2^D$, where $A$ and $D$
are a nucleus and the deuteron, respectively. In a JLab experiment, an
unexpectedly large nuclear modification slope $|dR_{\rm EMC}/dx|$ was found for
$^9$Be, which could be related to its clustering structure. We investigated a
mean conventional part of a nuclear structure function $F_2^A$ by a convolution
description with nucleon momentum distributions calculated by antisymmetrized
(or fermionic) molecular dynamics (AMD) and also by a simple shell model. We
found that clustering effects are small in the conventional part, so that the
JLab result could be associated with an internal nucleon modification or a
short-range nuclear correlation which is caused by high densities due to
cluster formation.
|
[
{
"created": "Mon, 4 Aug 2014 12:32:26 GMT",
"version": "v1"
}
] |
2015-06-22
|
[
[
"Hirai",
"M.",
""
],
[
"Kumano",
"S.",
""
],
[
"Saito",
"K.",
""
],
[
"Watanabe",
"T.",
""
]
] |
A clustering aspect is explained for the $^9$Be nucleus in charged-lepton deep inelastic scattering. Nuclear modifications of the structure function $F_2$ are studied by the ratio $R_{\rm EMC} = F_2^A /F_2^D$, where $A$ and $D$ are a nucleus and the deuteron, respectively. In a JLab experiment, an unexpectedly large nuclear modification slope $|dR_{\rm EMC}/dx|$ was found for $^9$Be, which could be related to its clustering structure. We investigated a mean conventional part of a nuclear structure function $F_2^A$ by a convolution description with nucleon momentum distributions calculated by antisymmetrized (or fermionic) molecular dynamics (AMD) and also by a simple shell model. We found that clustering effects are small in the conventional part, so that the JLab result could be associated with an internal nucleon modification or a short-range nuclear correlation which is caused by high densities due to cluster formation.
|
1604.06193
|
Rainer Sommer
|
Mattia Dalla Brida, Patrick Fritzsch, Tomasz Korzec, Alberto Ramos,
Stefan Sint, Rainer Sommer
|
Determination of the QCD $\Lambda$-parameter and the accuracy of
perturbation theory at high energies
|
6.5 pages including figures and references; version accepted for
publication in PRL
|
Phys. Rev. Lett. 117, 182001 (2016)
|
10.1103/PhysRevLett.117.182001
|
DESY 16-053, IFT-UAM/CSIC-16-029, CERN-TH-2016-060, TCDMATH 16-04,
WUB/16-00
|
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss the determination of the strong coupling
$\alpha_\mathrm{\overline{MS}}^{}(m_\mathrm{Z})$ or equivalently the QCD
$\Lambda$-parameter. Its determination requires the use of perturbation theory
in $\alpha_s(\mu)$ in some scheme, $s$, and at some energy scale $\mu$. The
higher the scale $\mu$ the more accurate perturbation theory becomes, owing to
asymptotic freedom. As one step in our computation of the $\Lambda$-parameter
in three-flavor QCD, we perform lattice computations in a scheme which allows
us to non-perturbatively reach very high energies, corresponding to $\alpha_s =
0.1$ and below. We find that (continuum) perturbation theory is very accurate
there, yielding a three percent error in the $\Lambda$-parameter, while data
around $\alpha_s \approx 0.2$ is clearly insufficient to quote such a
precision. It is important to realize that these findings are expected to be
generic, as our scheme has advantageous properties regarding the applicability
of perturbation theory.
|
[
{
"created": "Thu, 21 Apr 2016 06:49:35 GMT",
"version": "v1"
},
{
"created": "Tue, 27 Sep 2016 15:51:28 GMT",
"version": "v2"
}
] |
2016-11-02
|
[
[
"Brida",
"Mattia Dalla",
""
],
[
"Fritzsch",
"Patrick",
""
],
[
"Korzec",
"Tomasz",
""
],
[
"Ramos",
"Alberto",
""
],
[
"Sint",
"Stefan",
""
],
[
"Sommer",
"Rainer",
""
]
] |
We discuss the determination of the strong coupling $\alpha_\mathrm{\overline{MS}}^{}(m_\mathrm{Z})$ or equivalently the QCD $\Lambda$-parameter. Its determination requires the use of perturbation theory in $\alpha_s(\mu)$ in some scheme, $s$, and at some energy scale $\mu$. The higher the scale $\mu$ the more accurate perturbation theory becomes, owing to asymptotic freedom. As one step in our computation of the $\Lambda$-parameter in three-flavor QCD, we perform lattice computations in a scheme which allows us to non-perturbatively reach very high energies, corresponding to $\alpha_s = 0.1$ and below. We find that (continuum) perturbation theory is very accurate there, yielding a three percent error in the $\Lambda$-parameter, while data around $\alpha_s \approx 0.2$ is clearly insufficient to quote such a precision. It is important to realize that these findings are expected to be generic, as our scheme has advantageous properties regarding the applicability of perturbation theory.
|
hep-ph/0604098
|
Adam Szczepaniak
|
Adam P. Szczepaniak and Pawel Krupinski
|
Energy spectrum of the low-lying gluon excitations in the Coulomb gauge
|
8 pages, 8 figures
|
Phys.Rev. D73 (2006) 116002
|
10.1103/PhysRevD.73.116002
| null |
hep-ph
| null |
We compute the energy spectrum of low-lying gluonic excitations in the
presence of static quark-antiquark sources using Coulomb gauge and the
quasi-particle representation. Within the valence sector of the Fock space we
reproduce both, the overall normalization and the ordering of the spin-parity
multiplets. We discus how the interactions induced by the non-abelian Coulomb
kernel are central in to fine structure of the spectrum.
|
[
{
"created": "Wed, 12 Apr 2006 16:49:28 GMT",
"version": "v1"
}
] |
2009-11-11
|
[
[
"Szczepaniak",
"Adam P.",
""
],
[
"Krupinski",
"Pawel",
""
]
] |
We compute the energy spectrum of low-lying gluonic excitations in the presence of static quark-antiquark sources using Coulomb gauge and the quasi-particle representation. Within the valence sector of the Fock space we reproduce both, the overall normalization and the ordering of the spin-parity multiplets. We discus how the interactions induced by the non-abelian Coulomb kernel are central in to fine structure of the spectrum.
|
0712.1758
|
Daniel Gamermann
|
D. Gamermann and E. Oset
|
Hidden charm dynamically generated resonances and the $e^+e^-\to J/\psi
D \bar D$, $J/\psi D\bar D^*$ reactions
|
5 pages, 5 figures, 2 tables
|
Eur.Phys.J.A36:189-194,2008
|
10.1140/epja/i2007-10580-5
| null |
hep-ph hep-ex
| null |
We analyze two recent reactions of Belle, producing $D\bar D$ and $D\bar D^*$
states that have an enhancement of the invariant $D\bar D$, $D\bar D^*$ mass
distribution close to threshold, from the point of view that they might be
indicative of the existence of a hidden charm scalar and an axial vector meson
states below $D\bar D$ or $D\bar D^*$ thresholds, respectively. We conclude
that the data is compatible with the existing prediction of a hidden charm
scalar meson with mass around 3700 MeV, though other possibilities cannot be
discarded. The peak seen in the $D\bar D^*$ spectrum above threshold is,
however, unlikely to be due to a threshold enhancement produced by the
presence, below threshold, of the hidden charm axial vector meson X(3872).
|
[
{
"created": "Tue, 11 Dec 2007 16:35:57 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Gamermann",
"D.",
""
],
[
"Oset",
"E.",
""
]
] |
We analyze two recent reactions of Belle, producing $D\bar D$ and $D\bar D^*$ states that have an enhancement of the invariant $D\bar D$, $D\bar D^*$ mass distribution close to threshold, from the point of view that they might be indicative of the existence of a hidden charm scalar and an axial vector meson states below $D\bar D$ or $D\bar D^*$ thresholds, respectively. We conclude that the data is compatible with the existing prediction of a hidden charm scalar meson with mass around 3700 MeV, though other possibilities cannot be discarded. The peak seen in the $D\bar D^*$ spectrum above threshold is, however, unlikely to be due to a threshold enhancement produced by the presence, below threshold, of the hidden charm axial vector meson X(3872).
|
hep-ph/9702417
|
Alexander Dorokhov
|
A.E.Dorokhov, S.V. Esaibegyan, S.V. Mikhailov
|
Virtualities of Quarks and Gluons in QCD Vacuum and Nonlocal Condensates
within Single Instanton Approximation
|
12 pages, LATEX, no figures. Revised version contains two formulae
corrected and references updated
|
Phys.Rev.D56:4062-4068,1997
|
10.1103/PhysRevD.56.4062
|
E2-97-54 JINR, Dubna
|
hep-ph
| null |
We calculate the lowest-dimensional nonlocal quark and gluon condensates
within the single instanton approximation of the instanton liquid model. As a
result, we determine the values of average virtualities of quarks $\lambda_q^2$
and gluons $\lambda_g^2$ in the QCD vacuum and obtain parameterless predictions
for the ratio $\lambda_g^2/\lambda_q^2 = 12/5$, and for some ratios of
different vacuum condensates of higher dimensions. The nonlocal properties of
quark and gluon condensates are analyzed, and insufficiency of the single
instanton approximation is discussed.
|
[
{
"created": "Tue, 25 Feb 1997 14:37:28 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Mar 1997 14:08:08 GMT",
"version": "v2"
}
] |
2014-11-17
|
[
[
"Dorokhov",
"A. E.",
""
],
[
"Esaibegyan",
"S. V.",
""
],
[
"Mikhailov",
"S. V.",
""
]
] |
We calculate the lowest-dimensional nonlocal quark and gluon condensates within the single instanton approximation of the instanton liquid model. As a result, we determine the values of average virtualities of quarks $\lambda_q^2$ and gluons $\lambda_g^2$ in the QCD vacuum and obtain parameterless predictions for the ratio $\lambda_g^2/\lambda_q^2 = 12/5$, and for some ratios of different vacuum condensates of higher dimensions. The nonlocal properties of quark and gluon condensates are analyzed, and insufficiency of the single instanton approximation is discussed.
|
2305.09256
|
Chun-Wei Su
|
Chuan-Hung Chen, Cheng-Wei Chiang, Chun-Wei Su
|
Phenomenological study of a gauged ${L_\mu -L_\tau}$ model with a scalar
leptoquark
|
50 pages, 10 figures, typos corrected and references added
|
Phys.Rev.D 109 (2024) 5, 055038
|
10.1103/PhysRevD.109.055038
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A $Z'$ gauge boson with sub-GeV mass has acquired a significant interest in
phenomenology, particularly in view of the muon $g-2$ anomaly and coherent
elastic neutrino-nucleon scattering. The latter is challenged by the nuclear
recoil energy of a few tens of keV but has been observed by the COHERENT
experiment. To further reconcile the observed excesses in $R(D^{(*)})$ from
semileptonic charmful $B$ decays and in the $W$ boson mass, we investigate a
model with a gauged $U(1)_{L_\mu-L_\tau}$ symmetry and a scalar leptoquark. In
contrast to the mechanism that involves kinetic mixing between the gauge bosons
of $U(1)_{\rm em}$ and $U(1)_{L_\mu-L_\tau}$, we adopt a dynamical symmetry
breaking of $U(1)_{L_\mu-L_\tau}$ by incorporating an additional Higgs doublet.
Through mixing with the $U(1)_{L_\mu-L_\tau}$-charged Higgs doublet, new Higgs
decay channels $h\to Z_1 Z_1/Z_1 Z_2$ occur at percent-level branching ratios,
which could be accessible at the LHC. The $W$-mass anomaly observed by CDF II
can be potentially resolved through the enhancement in the oblique parameter
$T$. Due to the flavored gauge symmetry, the introduced scalar leptoquark
$S^{\frac{1}{3}}=(\bar{3},1,2/3)$ exhibits a unique coupling to the
$\tau$-lepton, offering an explanation for the excesses observed in
$R(D^{(*)})$. Moreover, $\tau \to \mu (Z_1\to ) e^- e^+$ via the resonant light
gauge boson decay can reach the sensitivity of Belle II at an integrated
luminosity of 50 ab$^{-1}$.
|
[
{
"created": "Tue, 16 May 2023 08:04:56 GMT",
"version": "v1"
},
{
"created": "Fri, 26 May 2023 16:47:46 GMT",
"version": "v2"
},
{
"created": "Sat, 23 Mar 2024 22:10:41 GMT",
"version": "v3"
}
] |
2024-03-26
|
[
[
"Chen",
"Chuan-Hung",
""
],
[
"Chiang",
"Cheng-Wei",
""
],
[
"Su",
"Chun-Wei",
""
]
] |
A $Z'$ gauge boson with sub-GeV mass has acquired a significant interest in phenomenology, particularly in view of the muon $g-2$ anomaly and coherent elastic neutrino-nucleon scattering. The latter is challenged by the nuclear recoil energy of a few tens of keV but has been observed by the COHERENT experiment. To further reconcile the observed excesses in $R(D^{(*)})$ from semileptonic charmful $B$ decays and in the $W$ boson mass, we investigate a model with a gauged $U(1)_{L_\mu-L_\tau}$ symmetry and a scalar leptoquark. In contrast to the mechanism that involves kinetic mixing between the gauge bosons of $U(1)_{\rm em}$ and $U(1)_{L_\mu-L_\tau}$, we adopt a dynamical symmetry breaking of $U(1)_{L_\mu-L_\tau}$ by incorporating an additional Higgs doublet. Through mixing with the $U(1)_{L_\mu-L_\tau}$-charged Higgs doublet, new Higgs decay channels $h\to Z_1 Z_1/Z_1 Z_2$ occur at percent-level branching ratios, which could be accessible at the LHC. The $W$-mass anomaly observed by CDF II can be potentially resolved through the enhancement in the oblique parameter $T$. Due to the flavored gauge symmetry, the introduced scalar leptoquark $S^{\frac{1}{3}}=(\bar{3},1,2/3)$ exhibits a unique coupling to the $\tau$-lepton, offering an explanation for the excesses observed in $R(D^{(*)})$. Moreover, $\tau \to \mu (Z_1\to ) e^- e^+$ via the resonant light gauge boson decay can reach the sensitivity of Belle II at an integrated luminosity of 50 ab$^{-1}$.
|
hep-ph/9802346
|
Chen Xiang-Song
|
Xiang-Song Chen and Fan Wang
|
Gauge invariance and hadron structure
|
This revised version gives a complete, comprehensive proof of our
conclusion, and explains why the specific calculations of Hoodbhoy, Ji and Lu
(hep-ph/9808305) do not necessarily contradict our theorem
| null | null | null |
hep-ph
| null |
We prove that the {\em gauge dependent} gluon spin, gluon and quark orbital
angular momenta operators have {\em gauge invariant} expectation values on
hadron states with {\em definite} momentum and polarization, therefore the
conventional decomposition of nucleon spin into contributions from the spin and
orbital angular momentum of quark and gluon is {\em gauge independent}. Similar
conclusions apply to the {\em gauge dependent} quark momentum and kinetic
energy operators, and accordingly nucleon momentum and mass structures.
|
[
{
"created": "Wed, 18 Feb 1998 12:38:19 GMT",
"version": "v1"
},
{
"created": "Sat, 19 Sep 1998 04:37:20 GMT",
"version": "v2"
}
] |
2007-05-23
|
[
[
"Chen",
"Xiang-Song",
""
],
[
"Wang",
"Fan",
""
]
] |
We prove that the {\em gauge dependent} gluon spin, gluon and quark orbital angular momenta operators have {\em gauge invariant} expectation values on hadron states with {\em definite} momentum and polarization, therefore the conventional decomposition of nucleon spin into contributions from the spin and orbital angular momentum of quark and gluon is {\em gauge independent}. Similar conclusions apply to the {\em gauge dependent} quark momentum and kinetic energy operators, and accordingly nucleon momentum and mass structures.
|
hep-ph/0210107
|
Marcello Lissia
|
Massimo Coraddu, Marcello Lissia, and Giuseppe Mezzorani
|
Ultra high energy photon showers in magnetic field:angular distribution
of produced particles
|
RevTex, 13 pages, 4 figures
| null |
10.1142/9789812705143_0033
|
INFNCA-TH0206
|
hep-ph
| null |
Ultra high energy (UHE) photons can initiate electromagnetic showers in
magnetic field. We analyze the two processes that determine the development of
the shower, $e^+ e^-$ pair creation and synchrotron radiation, and derive
formulae for the angular distribution of the produced particles. These formulae
are necessary to study the three-dimensional development of the shower.
|
[
{
"created": "Mon, 7 Oct 2002 15:54:16 GMT",
"version": "v1"
}
] |
2017-08-23
|
[
[
"Coraddu",
"Massimo",
""
],
[
"Lissia",
"Marcello",
""
],
[
"Mezzorani",
"Giuseppe",
""
]
] |
Ultra high energy (UHE) photons can initiate electromagnetic showers in magnetic field. We analyze the two processes that determine the development of the shower, $e^+ e^-$ pair creation and synchrotron radiation, and derive formulae for the angular distribution of the produced particles. These formulae are necessary to study the three-dimensional development of the shower.
|
2305.01894
|
Preeti Bhall
|
Preeti Bhall, Meenakshi Batra, Alka Upadhyay
|
Sea contribution to the charge radii and quadrupole moment of
$J^P=\frac{1}{2}^+, \frac{3}{2}^+$ baryons
| null |
Prog Theor Exp Phys (2023)
|
10.1093/ptep/ptad108
| null |
hep-ph nucl-th
|
http://creativecommons.org/licenses/by-sa/4.0/
|
An operator formalism is used on the wavefunction of baryons to compute their
charge radii and quadrupole moments. Total anti-symmetric wavefunction in spin,
color and flavor space is framed for $J^P=\frac{1}{2}^+$ nucleons and
$J^P=\frac{3}{2}^+$ hyperons. To understand the importance of sea, statistical
model is used in conjugation with the detailed balance principle. Within the
statistical approach, the importance of sea with quarks and gluons are studied
using the relevant probabilities that are associated with spin, flavor, and
color space. The present work also focuses on individual contributions of
valence and sea which contains terms of scalar, vector and tensor sea. The
obtained results are in agreement with available theories and few experimental
outcomes. Our computed results may provide important information for upcoming
experimental findings.
|
[
{
"created": "Wed, 3 May 2023 05:03:53 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Jul 2023 10:56:35 GMT",
"version": "v2"
}
] |
2023-10-04
|
[
[
"Bhall",
"Preeti",
""
],
[
"Batra",
"Meenakshi",
""
],
[
"Upadhyay",
"Alka",
""
]
] |
An operator formalism is used on the wavefunction of baryons to compute their charge radii and quadrupole moments. Total anti-symmetric wavefunction in spin, color and flavor space is framed for $J^P=\frac{1}{2}^+$ nucleons and $J^P=\frac{3}{2}^+$ hyperons. To understand the importance of sea, statistical model is used in conjugation with the detailed balance principle. Within the statistical approach, the importance of sea with quarks and gluons are studied using the relevant probabilities that are associated with spin, flavor, and color space. The present work also focuses on individual contributions of valence and sea which contains terms of scalar, vector and tensor sea. The obtained results are in agreement with available theories and few experimental outcomes. Our computed results may provide important information for upcoming experimental findings.
|
hep-ph/9809443
|
Masashi Wakamatsu Ohtsubo Laboratory
|
Masashi Wakamatsu and Takanori Kubota (Osaka Univ.)
|
Chiral Symmetry and the Nucleon Spin Structure Functions
|
46pages, LaTeX, 16 Postscript figures
|
Phys.Rev.D60:034020,1999
|
10.1103/PhysRevD.60.034020
| null |
hep-ph
| null |
We carry out a systematic investigation of twist-two spin dependent structure
functions of the nucleon within the framework of the chiral quark soliton model
(CQSM) by paying special attention to the role of chiral symmetry of QCD. The
importance of chiral symmetry is illustrated through the good reproduction of
the recent SLAC data for the neutron spin structure function $g_1^n (x,Q^2)$.
We also observe substantial difference between the predictions of the
longitudinally polarized distribution functions and those of the transversity
distribution functions. That the chiral symmetry may be responsible for this
difference is seen in the isospin dependence of the corresponding first
moments, i.e. the axial and tensor charges. The CQSM predicts $g_A^{(0)} /
g_A^{(3)} \simeq 0.25$ for the ratio of the isoscalar to isovector axial
charges, while $g_T^{(0)} / g_T^{(3)} \simeq 0.46$ for the ratio of the
isoscalar to isovector tensor charges, which should be compared with the
prediction $g_A^{(0)} / g_A^{(3)} = g_T^{(0)} / g_T^{(3)} = 3 / 5$ of the
constituent quark model or of the naive MIT bag model without proper account of
chiral symmetry. Another prominent prediction of the CQSM is the opposite
polarization of the $\bar{u}$ and $\bar{d}$ antiquarks, thereby indicating the
SU(2) asymmetric sea quark (spin) polarization in the nucleon.
|
[
{
"created": "Fri, 18 Sep 1998 00:50:11 GMT",
"version": "v1"
}
] |
2010-04-06
|
[
[
"Wakamatsu",
"Masashi",
"",
"Osaka Univ."
],
[
"Kubota",
"Takanori",
"",
"Osaka Univ."
]
] |
We carry out a systematic investigation of twist-two spin dependent structure functions of the nucleon within the framework of the chiral quark soliton model (CQSM) by paying special attention to the role of chiral symmetry of QCD. The importance of chiral symmetry is illustrated through the good reproduction of the recent SLAC data for the neutron spin structure function $g_1^n (x,Q^2)$. We also observe substantial difference between the predictions of the longitudinally polarized distribution functions and those of the transversity distribution functions. That the chiral symmetry may be responsible for this difference is seen in the isospin dependence of the corresponding first moments, i.e. the axial and tensor charges. The CQSM predicts $g_A^{(0)} / g_A^{(3)} \simeq 0.25$ for the ratio of the isoscalar to isovector axial charges, while $g_T^{(0)} / g_T^{(3)} \simeq 0.46$ for the ratio of the isoscalar to isovector tensor charges, which should be compared with the prediction $g_A^{(0)} / g_A^{(3)} = g_T^{(0)} / g_T^{(3)} = 3 / 5$ of the constituent quark model or of the naive MIT bag model without proper account of chiral symmetry. Another prominent prediction of the CQSM is the opposite polarization of the $\bar{u}$ and $\bar{d}$ antiquarks, thereby indicating the SU(2) asymmetric sea quark (spin) polarization in the nucleon.
|
2104.10260
|
Eugenio Megias
|
Eugenio Megias, Mariano Quiros
|
The Continuum Linear Dilaton
|
33 pages, 7 figures
| null |
10.5506/APhysPolB.52.711
| null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Continuum spectra can be a way out to alleviate the tension generated by the
elusiveness of narrow resonances of new physics in direct experimental
searches. Motivated by the latter, we consider the linear dilaton model with a
continuum spectrum of KK modes. It is provided by a critical exponential bulk
potential for the scalar field stabilizing the distance, between the UV
boundary at $y=0$ and a naked (good) singularity at $y=y_s$, in proper
coordinates, which corresponds in conformal coordinates to $z_s\to\infty$. The
cutoff $M_s$ in this theory is an intermediate scale $M_s\simeq 10^{-5}M_{\rm
Pl}$ and the warped factor solves the hierarchy between $M_s$ and the TeV,
while the hierarchy between $M_{\rm Pl}$ and $M_s$ has to be solved by a
(Little) String Theory with coupling $g_s\simeq 10^{-5}$. The Standard Model is
localized on a 4D IR brane. The graviton and radion Green's and spectral
functions have a continuum of states with a TeV mass gap, and isolated poles
consisting on the 4D graviton and the light radion/dilaton. We construct the
effective field theory below the mass gap where the continua of KK modes are
integrated out, generating a set of dimension eight operators which contribute
to low energy electroweak precision observables, and high energy violation of
unitarity in vector boson scattering processes. The radion mass depends on the
stabilizing UV brane potential and its wave function is localized toward the IR
which enhances its coupling with the SM fields.
|
[
{
"created": "Tue, 20 Apr 2021 21:45:54 GMT",
"version": "v1"
}
] |
2021-07-07
|
[
[
"Megias",
"Eugenio",
""
],
[
"Quiros",
"Mariano",
""
]
] |
Continuum spectra can be a way out to alleviate the tension generated by the elusiveness of narrow resonances of new physics in direct experimental searches. Motivated by the latter, we consider the linear dilaton model with a continuum spectrum of KK modes. It is provided by a critical exponential bulk potential for the scalar field stabilizing the distance, between the UV boundary at $y=0$ and a naked (good) singularity at $y=y_s$, in proper coordinates, which corresponds in conformal coordinates to $z_s\to\infty$. The cutoff $M_s$ in this theory is an intermediate scale $M_s\simeq 10^{-5}M_{\rm Pl}$ and the warped factor solves the hierarchy between $M_s$ and the TeV, while the hierarchy between $M_{\rm Pl}$ and $M_s$ has to be solved by a (Little) String Theory with coupling $g_s\simeq 10^{-5}$. The Standard Model is localized on a 4D IR brane. The graviton and radion Green's and spectral functions have a continuum of states with a TeV mass gap, and isolated poles consisting on the 4D graviton and the light radion/dilaton. We construct the effective field theory below the mass gap where the continua of KK modes are integrated out, generating a set of dimension eight operators which contribute to low energy electroweak precision observables, and high energy violation of unitarity in vector boson scattering processes. The radion mass depends on the stabilizing UV brane potential and its wave function is localized toward the IR which enhances its coupling with the SM fields.
|
1902.01742
|
S Dev Sharma
|
S. Dev, Desh Raj, Radha Raman Gautam, Lal Singh
|
New mixing schemes for (3+1) neutrinos
|
21 pages, 6 figures, 5 tables
| null |
10.1016/j.nuclphysb.2019.02.003
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We propose new mixing schemes for (3+1) neutrinos which describe mixing among
active-active and active-sterile neutrinos. The mixing matrix in these mixing
schemes can be factored into a zeroth order flavor symmetric part and another
part representing small perturbations needed for generating non-zero $U_{e3}$,
nonmaximal $\theta_{23}$, CP violation and active-sterile mixing. We find
interesting correlations amongst various neutrino mixing angles and, also,
calculate the parameter space for various parameters.
|
[
{
"created": "Tue, 5 Feb 2019 15:33:29 GMT",
"version": "v1"
}
] |
2019-03-27
|
[
[
"Dev",
"S.",
""
],
[
"Raj",
"Desh",
""
],
[
"Gautam",
"Radha Raman",
""
],
[
"Singh",
"Lal",
""
]
] |
We propose new mixing schemes for (3+1) neutrinos which describe mixing among active-active and active-sterile neutrinos. The mixing matrix in these mixing schemes can be factored into a zeroth order flavor symmetric part and another part representing small perturbations needed for generating non-zero $U_{e3}$, nonmaximal $\theta_{23}$, CP violation and active-sterile mixing. We find interesting correlations amongst various neutrino mixing angles and, also, calculate the parameter space for various parameters.
|
1409.3252
|
Christoph Bobeth
|
Christoph Bobeth and Martin Gorbahn and Stefan Vickers
|
Weak annihilation and new physics in charmless $B \to M M$ decays
|
34 pages, 12 figures
| null | null |
FLAVOUR(267104)-ERC-78, LTH 1022
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We use currently available data of nonleptonic charmless 2-body $B\to MM$
decays ($MM = PP, PV, VV$) that are mediated by $b\to (d, s)$ QCD- and
QED-penguin operators to study weak annihilation and new-physics effects in the
framework of QCD factorization. In particular we introduce one weak
annihilation parameter for decays related by ($u \leftrightarrow d$) quark
interchange and test this universality assumption. Within the standard model,
the data supports this assumption with the only exceptions in the $B\to K \pi$
system, which exhibits the well-known "$\Delta A_{CP}$ puzzle", and some
tensions in $B \to K^* \phi$. Beyond the standard model, we simultaneously
determine weak-annihilation and new-physics parameters from data, employing
model-independent scenarios that address the "$\Delta A_{CP}$ puzzle", such as
QED-penguins and $b\to s \bar{u}u$ current-current operators. We discuss also
possibilities that allow further tests of our assumption once improved
measurements from LHCb and Belle II become available.
|
[
{
"created": "Wed, 10 Sep 2014 20:50:39 GMT",
"version": "v1"
}
] |
2014-09-12
|
[
[
"Bobeth",
"Christoph",
""
],
[
"Gorbahn",
"Martin",
""
],
[
"Vickers",
"Stefan",
""
]
] |
We use currently available data of nonleptonic charmless 2-body $B\to MM$ decays ($MM = PP, PV, VV$) that are mediated by $b\to (d, s)$ QCD- and QED-penguin operators to study weak annihilation and new-physics effects in the framework of QCD factorization. In particular we introduce one weak annihilation parameter for decays related by ($u \leftrightarrow d$) quark interchange and test this universality assumption. Within the standard model, the data supports this assumption with the only exceptions in the $B\to K \pi$ system, which exhibits the well-known "$\Delta A_{CP}$ puzzle", and some tensions in $B \to K^* \phi$. Beyond the standard model, we simultaneously determine weak-annihilation and new-physics parameters from data, employing model-independent scenarios that address the "$\Delta A_{CP}$ puzzle", such as QED-penguins and $b\to s \bar{u}u$ current-current operators. We discuss also possibilities that allow further tests of our assumption once improved measurements from LHCb and Belle II become available.
|
1911.09314
|
Gudrun Heinrich
|
Long Chen, Gudrun Heinrich, Stephan Jahn, Stephen P. Jones, Matthias
Kerner, Johannes Schlenk, Hiroshi Yokoya
|
Photon pair production in gluon fusion: Top quark effects at NLO with
threshold matching
|
Version 2: figure 6 added; version published in JHEP
|
JHEP 04 (2020) 115
|
10.1007/JHEP04(2020)115
|
CERN-TH-2019-195, MPP-2019-236, PSI-PR-19-24, ZU-TH 48/19
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present a calculation of the NLO QCD corrections to the loop-induced
production of a photon pair through gluon fusion, including massive top quarks
at two loops, where the two-loop integrals are calculated numerically. Matching
the fixed-order NLO results to a threshold expansion, we obtain accurate
results around the top quark pair production threshold. We analyse how the top
quark threshold corrections affect distributions of the photon pair invariant
mass and comment on the possibility of determining the top quark mass from
precision measurements of the diphoton invariant mass spectrum.
|
[
{
"created": "Thu, 21 Nov 2019 07:11:11 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Oct 2020 14:13:58 GMT",
"version": "v2"
}
] |
2020-10-14
|
[
[
"Chen",
"Long",
""
],
[
"Heinrich",
"Gudrun",
""
],
[
"Jahn",
"Stephan",
""
],
[
"Jones",
"Stephen P.",
""
],
[
"Kerner",
"Matthias",
""
],
[
"Schlenk",
"Johannes",
""
],
[
"Yokoya",
"Hiroshi",
""
]
] |
We present a calculation of the NLO QCD corrections to the loop-induced production of a photon pair through gluon fusion, including massive top quarks at two loops, where the two-loop integrals are calculated numerically. Matching the fixed-order NLO results to a threshold expansion, we obtain accurate results around the top quark pair production threshold. We analyse how the top quark threshold corrections affect distributions of the photon pair invariant mass and comment on the possibility of determining the top quark mass from precision measurements of the diphoton invariant mass spectrum.
|
0903.0531
|
Werner Rodejohann
|
Adisorn Adulpravitchai, Alexander Blum, Werner Rodejohann
|
Golden Ratio Prediction for Solar Neutrino Mixing
|
15 pages, 1 figure. Matches published version
|
NewJ.Phys.11:063026,2009
|
10.1088/1367-2630/11/6/063026
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
It has recently been speculated that the solar neutrino mixing angle is
connected to the golden ratio phi. Two such proposals have been made, cot
theta_{12} = phi and cos theta_{12} = phi/2. We compare these Ansatze and
discuss a model leading to cos theta_{12} = phi/2 based on the dihedral group
D_{10}. This symmetry is a natural candidate because the angle in the
expression cos theta_{12} = phi/2 is simply pi/5, or 36 degrees. This is the
exterior angle of a decagon and D_{10} is its rotational symmetry group. We
also estimate radiative corrections to the golden ratio predictions.
|
[
{
"created": "Tue, 3 Mar 2009 13:38:39 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Jun 2009 09:29:58 GMT",
"version": "v2"
}
] |
2009-06-17
|
[
[
"Adulpravitchai",
"Adisorn",
""
],
[
"Blum",
"Alexander",
""
],
[
"Rodejohann",
"Werner",
""
]
] |
It has recently been speculated that the solar neutrino mixing angle is connected to the golden ratio phi. Two such proposals have been made, cot theta_{12} = phi and cos theta_{12} = phi/2. We compare these Ansatze and discuss a model leading to cos theta_{12} = phi/2 based on the dihedral group D_{10}. This symmetry is a natural candidate because the angle in the expression cos theta_{12} = phi/2 is simply pi/5, or 36 degrees. This is the exterior angle of a decagon and D_{10} is its rotational symmetry group. We also estimate radiative corrections to the golden ratio predictions.
|
0711.0286
|
Yuji Kajiyama
|
Yuji Kajiyama
|
Lepton Flavor Violating tau decay by R-Parity Violation in a Family
Symmetry
|
3 pages. Talk given at Summer Institute 2007, Aug. 3-10, 2007,
Fuji-Yoshida, Japan
| null | null | null |
hep-ph
| null |
In this talk, we investigate Lepton Flavor Violating (LFV) tau decay by
R-Parity Violating (RPV) operators controlled by a non-Abelian discrete $Q_6$
family symmetry. We assume that only a family symmetry determines the whole
flavor structure of a model, and the model indicates specific predictions of
LFV tau decay processes by RPV operators. We predict $BR(\tau \to 3e)/BR(\tau
\to 3 \mu) \sim 4 m_{\mu}^2/m_{\tau}^2$ in a $Q_6$ family symmetric model.
|
[
{
"created": "Fri, 2 Nov 2007 11:17:25 GMT",
"version": "v1"
}
] |
2007-11-05
|
[
[
"Kajiyama",
"Yuji",
""
]
] |
In this talk, we investigate Lepton Flavor Violating (LFV) tau decay by R-Parity Violating (RPV) operators controlled by a non-Abelian discrete $Q_6$ family symmetry. We assume that only a family symmetry determines the whole flavor structure of a model, and the model indicates specific predictions of LFV tau decay processes by RPV operators. We predict $BR(\tau \to 3e)/BR(\tau \to 3 \mu) \sim 4 m_{\mu}^2/m_{\tau}^2$ in a $Q_6$ family symmetric model.
|
0810.3886
|
Vivian de la Incera
|
Efrain J. Ferrer and Vivian de la Incera
|
Super-Dense Matter at Super- Strong Magnetic Fields
|
Talk given at the 4th International Workshop on the Dark Side of the
Universe, Egypt, 1st-5th June, 2008. One new reference added
|
AIP Conf.Proc.1115:99-104,2009
|
10.1063/1.3131535
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Our Universe is full of regions where extreme physical conditions are
realized. A most intriguing case is the super-dense core of neutron stars, some
of which also have super-strong magnetic fields, hence called magnetars. In
this paper we review the current understanding of the physical properties of
the different phases of quark matter at very high densities in the presence of
large magnetic fields. We also discuss how the Meissner instability produced at
moderate densities by a pairing stress due to the medium neutrality and
$\beta$-equilibrium constraints can lead to the spontaneous generation of a
magnetic field.
|
[
{
"created": "Tue, 21 Oct 2008 17:52:33 GMT",
"version": "v1"
},
{
"created": "Mon, 15 Dec 2008 21:11:03 GMT",
"version": "v2"
}
] |
2009-05-01
|
[
[
"Ferrer",
"Efrain J.",
""
],
[
"de la Incera",
"Vivian",
""
]
] |
Our Universe is full of regions where extreme physical conditions are realized. A most intriguing case is the super-dense core of neutron stars, some of which also have super-strong magnetic fields, hence called magnetars. In this paper we review the current understanding of the physical properties of the different phases of quark matter at very high densities in the presence of large magnetic fields. We also discuss how the Meissner instability produced at moderate densities by a pairing stress due to the medium neutrality and $\beta$-equilibrium constraints can lead to the spontaneous generation of a magnetic field.
|
2407.17748
|
Jie Liu
|
Jie Liu, He-Xu Zhang, Hiroyuki Ishida, Shinya Matsuzaki
|
Walking-dilaton hybrid inflation with $B-L$ Higgs embedded in dynamical
scalegenesis
|
14 pages, 1 figure
| null | null | null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
We propose a hybrid inflationary scenario based on eight-flavor hidden QCD
with the hidden colored fermions being in part gauged under $U(1)_{B-L}$. This
hidden QCD is almost scale-invariant, so-called walking, and predicts the light
scalar meson (the walking dilaton) associated with the spontaneous scale
breaking, which develops the Coleman-Weinberg (CW) type potential as the
consequence of the nonperturbative scale anomaly, hence plays the role of an
inflaton of the small-field inflation. The $U(1)_{B-L}$ Higgs is coupled to the
walking dilaton inflaton, which is dynamically induced from the so-called
bosonic seesaw mechanism. We explore the hybrid inflation system involving the
walking dilaton inflaton and the $U(1)_{B-L}$ Higgs as a waterfall field. We
find that observed inflation parameters tightly constrain the $U(1)_{B-L}$
breaking scale as well as the walking dynamical scale to be $\sim 10^9$ GeV and
$\sim 10^{14}$ GeV, respectively, so as to make the waterfall mechanism worked.
The lightest walking pion mass is then predicted to be around 500 GeV.
Phenomenological perspectives including embedding of the dynamical electroweak
scalegenesis and possible impacts on the thermal leptogenesis are also
addressed.
|
[
{
"created": "Thu, 25 Jul 2024 03:48:18 GMT",
"version": "v1"
}
] |
2024-07-26
|
[
[
"Liu",
"Jie",
""
],
[
"Zhang",
"He-Xu",
""
],
[
"Ishida",
"Hiroyuki",
""
],
[
"Matsuzaki",
"Shinya",
""
]
] |
We propose a hybrid inflationary scenario based on eight-flavor hidden QCD with the hidden colored fermions being in part gauged under $U(1)_{B-L}$. This hidden QCD is almost scale-invariant, so-called walking, and predicts the light scalar meson (the walking dilaton) associated with the spontaneous scale breaking, which develops the Coleman-Weinberg (CW) type potential as the consequence of the nonperturbative scale anomaly, hence plays the role of an inflaton of the small-field inflation. The $U(1)_{B-L}$ Higgs is coupled to the walking dilaton inflaton, which is dynamically induced from the so-called bosonic seesaw mechanism. We explore the hybrid inflation system involving the walking dilaton inflaton and the $U(1)_{B-L}$ Higgs as a waterfall field. We find that observed inflation parameters tightly constrain the $U(1)_{B-L}$ breaking scale as well as the walking dynamical scale to be $\sim 10^9$ GeV and $\sim 10^{14}$ GeV, respectively, so as to make the waterfall mechanism worked. The lightest walking pion mass is then predicted to be around 500 GeV. Phenomenological perspectives including embedding of the dynamical electroweak scalegenesis and possible impacts on the thermal leptogenesis are also addressed.
|
0810.1727
|
Jens Braun
|
Jens Braun
|
The QCD Phase Boundary from Quark-Gluon Dynamics
|
49 pages, 3 figures; references added and discussion expanded
(matches Eur. Phys. J. C version)
|
Eur.Phys.J.C64:459-482,2009
|
10.1140/epjc/s10052-009-1136-6
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study one-flavor QCD at finite temperature and chemical potential using
the functional renormalization group. We discuss the chiral phase transition in
QCD and its order with its underlying mechanism in terms of quarks and gluons
and analyze the dependence of the phase transition temperature on small quark
chemical potentials. Our result for the curvature of the phase boundary at
small quark chemical potential relies on only a single input parameter, the
value of the strong coupling at the Z mass scale.
|
[
{
"created": "Thu, 9 Oct 2008 19:55:07 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Oct 2009 11:50:14 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Braun",
"Jens",
""
]
] |
We study one-flavor QCD at finite temperature and chemical potential using the functional renormalization group. We discuss the chiral phase transition in QCD and its order with its underlying mechanism in terms of quarks and gluons and analyze the dependence of the phase transition temperature on small quark chemical potentials. Our result for the curvature of the phase boundary at small quark chemical potential relies on only a single input parameter, the value of the strong coupling at the Z mass scale.
|
2312.09273
|
Taylor Murphy
|
Linda M. Carpenter, Katherine Schwind, Taylor Murphy
|
Leptonic signatures of color-sextet scalars II: Exploiting unique
large-$E_{\text{T}}^{\text{miss}}$ signals at the LHC
|
16 pages, 11 figures. Updated to resemble Phys. Rev. D Version of
Record
|
Phys. Rev. D 109, 075010 (2024)
|
10.1103/PhysRevD.109.075010
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The diverse and distinct collider phenomenology of color-sextet scalars
motivates thorough investigation of their effective couplings to the Standard
Model at the LHC. Some of the more unique sextet signals involve not only jets
but also leptons. In previous work, we proposed an LHC search for color-sextet
scalars in a channel with jets and a hard opposite-sign lepton pair, which
results from a dimension-six coupling. In this sequel we study the counterpart
processes with neutrinos, which produce jets in association with missing
transverse energy ($E_{\text{T}}^{\text{miss}}$) in addition to possible
leptons. We consider multiple search channels, including both single and pair
sextet production, all characterized by significant missing energy and some
featuring distinctive kinematic features. Our multifaceted study consists of
three reinterpreted existing searches and a joint-likelihood analysis designed
by us to maximize HL-LHC sensitivity to single sextet production. We show that
our dedicated strategy in the jets + lepton + $E_{\text{T}}^{\text{miss}}$
channel can supersede today's limits from reinterpreted searches, and we make
sensitivity projections for the HL-LHC. Altogether, our analysis can exclude
sextet scalars lighter than 4.4 TeV or probe effective cutoffs as high as 16.8
TeV.
|
[
{
"created": "Thu, 14 Dec 2023 19:00:00 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Apr 2024 14:17:34 GMT",
"version": "v2"
}
] |
2024-04-09
|
[
[
"Carpenter",
"Linda M.",
""
],
[
"Schwind",
"Katherine",
""
],
[
"Murphy",
"Taylor",
""
]
] |
The diverse and distinct collider phenomenology of color-sextet scalars motivates thorough investigation of their effective couplings to the Standard Model at the LHC. Some of the more unique sextet signals involve not only jets but also leptons. In previous work, we proposed an LHC search for color-sextet scalars in a channel with jets and a hard opposite-sign lepton pair, which results from a dimension-six coupling. In this sequel we study the counterpart processes with neutrinos, which produce jets in association with missing transverse energy ($E_{\text{T}}^{\text{miss}}$) in addition to possible leptons. We consider multiple search channels, including both single and pair sextet production, all characterized by significant missing energy and some featuring distinctive kinematic features. Our multifaceted study consists of three reinterpreted existing searches and a joint-likelihood analysis designed by us to maximize HL-LHC sensitivity to single sextet production. We show that our dedicated strategy in the jets + lepton + $E_{\text{T}}^{\text{miss}}$ channel can supersede today's limits from reinterpreted searches, and we make sensitivity projections for the HL-LHC. Altogether, our analysis can exclude sextet scalars lighter than 4.4 TeV or probe effective cutoffs as high as 16.8 TeV.
|
1804.07732
|
Davide Racco
|
Jos\'e Ram\'on Espinosa, Davide Racco, Antonio Riotto
|
A Cosmological Signature of the SM Higgs Instability: Gravitational
Waves
|
17+7 pages, 12 figures. v2: corrected an error in the numerical
calculation of the bispectrum and updated the corresponding plots, without
substantial changes in the results. v3: updated some details of the
discussion, and added a comparison with similar results derived in the
literature
| null |
10.1088/1475-7516/2018/09/012
| null |
hep-ph astro-ph.CO gr-qc hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A fundamental property of the Standard Model is that the Higgs potential
becomes unstable at large values of the Higgs field. For the current central
values of the Higgs and top masses, the instability scale is about $10^{11}$
GeV and therefore not accessible by colliders. We show that a possible
signature of the Standard Model Higgs instability is the production of
gravitational waves sourced by Higgs fluctuations generated during inflation.
We fully characterise the two-point correlator of such gravitational waves by
computing its amplitude, the frequency at peak, the spectral index, as well as
their three-point correlators for various polarisations. We show that,
depending on the Higgs and top masses, either LISA or the Einstein Telescope
and Advanced-Ligo, could detect such stochastic background of gravitational
waves. In this sense, collider and gravitational wave physics can provide
fundamental and complementary informations. Furthermore, the consistency
relation among the three- and the two-point correlators could provide an
efficient tool to ascribe the detected gravitational waves to the Standard
Model itself. Since the mechanism described in this paper might also be
responsible for the generation of dark matter under the form of primordial
black holes, this latter hypothesis may find its confirmation through the
detection of gravitational waves.
|
[
{
"created": "Fri, 20 Apr 2018 17:13:45 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Nov 2018 04:01:33 GMT",
"version": "v2"
},
{
"created": "Thu, 23 May 2019 16:09:36 GMT",
"version": "v3"
}
] |
2019-05-24
|
[
[
"Espinosa",
"José Ramón",
""
],
[
"Racco",
"Davide",
""
],
[
"Riotto",
"Antonio",
""
]
] |
A fundamental property of the Standard Model is that the Higgs potential becomes unstable at large values of the Higgs field. For the current central values of the Higgs and top masses, the instability scale is about $10^{11}$ GeV and therefore not accessible by colliders. We show that a possible signature of the Standard Model Higgs instability is the production of gravitational waves sourced by Higgs fluctuations generated during inflation. We fully characterise the two-point correlator of such gravitational waves by computing its amplitude, the frequency at peak, the spectral index, as well as their three-point correlators for various polarisations. We show that, depending on the Higgs and top masses, either LISA or the Einstein Telescope and Advanced-Ligo, could detect such stochastic background of gravitational waves. In this sense, collider and gravitational wave physics can provide fundamental and complementary informations. Furthermore, the consistency relation among the three- and the two-point correlators could provide an efficient tool to ascribe the detected gravitational waves to the Standard Model itself. Since the mechanism described in this paper might also be responsible for the generation of dark matter under the form of primordial black holes, this latter hypothesis may find its confirmation through the detection of gravitational waves.
|
1306.0365
|
Jan O. Eeg
|
Teresa Palmer and Jan O. Eeg
|
Form factors for semileptonic D decays
|
22 pages, 8 figures
|
Phys. Rev. D 89, 034013 (2014)
|
10.1103/PhysRevD.89.034013
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the form factors for semileptonic decays of $D$-mesons. That is, we
consider the matrix element of the weak left-handed quark current for the
transitions $D \rightarrow P$ and $D \rightarrow V$, where $P$ and $V$ are
light pseudoscalar or vector mesons, respectively. Our motivation to perform
the present study of these form factors are future calculations of non-leptonic
decay amplitudes.
We consider the form factors within a class of chiral quark models.
Especially, we study how the Large Energy Effective Theory (LEET) limit works
for $D$-meson decays. Compared to previous work we also introduce light vector
mesons $V = \rho, K^*,...$ within chiral quark models. In order to determine
some of the parameters in our model, we use existing data and results based on
some other methods like lattice calculations, light-cone sum rules, and
heavy-light chiral perturbation theory. We also obtain some predictions within
our framework.
|
[
{
"created": "Mon, 3 Jun 2013 11:44:43 GMT",
"version": "v1"
}
] |
2014-02-19
|
[
[
"Palmer",
"Teresa",
""
],
[
"Eeg",
"Jan O.",
""
]
] |
We study the form factors for semileptonic decays of $D$-mesons. That is, we consider the matrix element of the weak left-handed quark current for the transitions $D \rightarrow P$ and $D \rightarrow V$, where $P$ and $V$ are light pseudoscalar or vector mesons, respectively. Our motivation to perform the present study of these form factors are future calculations of non-leptonic decay amplitudes. We consider the form factors within a class of chiral quark models. Especially, we study how the Large Energy Effective Theory (LEET) limit works for $D$-meson decays. Compared to previous work we also introduce light vector mesons $V = \rho, K^*,...$ within chiral quark models. In order to determine some of the parameters in our model, we use existing data and results based on some other methods like lattice calculations, light-cone sum rules, and heavy-light chiral perturbation theory. We also obtain some predictions within our framework.
|
1810.11993
|
Martin Hansen
|
Martin Hansen, Kasper Lang{\ae}ble, Francesco Sannino
|
Chiral Perturbation Theory with an Isosinglet Scalar
|
11 pages, 3 figures, 1 table. Talk given at XIII Quark Confinement
and the Hadron Spectrum, 31 July - 6 August 2018, Maynooth University,
Ireland
| null | null | null |
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present an extension of chiral perturbation theory that explicitly
includes an isosinglet scalar in the Lagrangian. The dynamical effects from the
scalar state is of phenomenological relevance in theories where the mass of the
isosinglet scalar is comparable to the mass of the pseudo-Goldstone bosons.
This near-degeneracy of states is for example observed in certain
near-conformal BSM models. From the Lagrangian we calculate the one-loop
radiative corrections to the pion mass, the pion decay constant, and the scalar
mass. We then proceed and use the results to fit numerical lattice data for an
SU(3) gauge theory with $N_f=8$ light flavours in the fundamental
representation.
|
[
{
"created": "Mon, 29 Oct 2018 08:14:42 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Jun 2019 07:44:15 GMT",
"version": "v2"
}
] |
2019-06-04
|
[
[
"Hansen",
"Martin",
""
],
[
"Langæble",
"Kasper",
""
],
[
"Sannino",
"Francesco",
""
]
] |
We present an extension of chiral perturbation theory that explicitly includes an isosinglet scalar in the Lagrangian. The dynamical effects from the scalar state is of phenomenological relevance in theories where the mass of the isosinglet scalar is comparable to the mass of the pseudo-Goldstone bosons. This near-degeneracy of states is for example observed in certain near-conformal BSM models. From the Lagrangian we calculate the one-loop radiative corrections to the pion mass, the pion decay constant, and the scalar mass. We then proceed and use the results to fit numerical lattice data for an SU(3) gauge theory with $N_f=8$ light flavours in the fundamental representation.
|
1106.4709
|
Guohuai Zhu
|
Guohuai Zhu
|
Implications of the recent measurement of pure annihilation $B_s \to
\pi^+ \pi^-$ decays in QCD factorization
|
11 pages, 3 figures, accepted for publication in Phys. Lett. B
| null |
10.1016/j.physletb.2011.07.045
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The CDF 3.7 sigma evidence of pure annihilation $B_s \to \pi^+ \pi^-$ decays,
if confirmed, would imply a large annihilation scenario in the QCD
factorization approach. This is somewhat unexpected as the large annihilation
scenario was disfavored in previous studies. In this paper we reinvestigate the
role of annihilation topology in QCD factorization. We find that it is not easy
to reach the CDF central value of $B_s \to \pi^+ \pi^-$ decays when other decay
channels are considered. Our analysis also reveals that, for well-measured
charmless B decays into two final pseudoscalar mesons, the QCD factorization
predictions with large annihilation parameters show good agreement with the
experimental data except $B_s \to K^+ K^-$ and $B_d \to K^0 \bar{K}^0$ decays.
Though other possibilities can not be excluded, this may indicate that the
SU(3) flavor symmetry breaking should be taken into account for the
annihilation topology. In addition, there are different annihilation
topologies, so that somewhat different annihilation parameters may be chosen
for different final states and different annihilation topologies. If so, the
predictive power of the QCD factorization method may be rather limited for many
decay channels.
|
[
{
"created": "Thu, 23 Jun 2011 13:12:42 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Jul 2011 01:52:09 GMT",
"version": "v2"
}
] |
2015-05-28
|
[
[
"Zhu",
"Guohuai",
""
]
] |
The CDF 3.7 sigma evidence of pure annihilation $B_s \to \pi^+ \pi^-$ decays, if confirmed, would imply a large annihilation scenario in the QCD factorization approach. This is somewhat unexpected as the large annihilation scenario was disfavored in previous studies. In this paper we reinvestigate the role of annihilation topology in QCD factorization. We find that it is not easy to reach the CDF central value of $B_s \to \pi^+ \pi^-$ decays when other decay channels are considered. Our analysis also reveals that, for well-measured charmless B decays into two final pseudoscalar mesons, the QCD factorization predictions with large annihilation parameters show good agreement with the experimental data except $B_s \to K^+ K^-$ and $B_d \to K^0 \bar{K}^0$ decays. Though other possibilities can not be excluded, this may indicate that the SU(3) flavor symmetry breaking should be taken into account for the annihilation topology. In addition, there are different annihilation topologies, so that somewhat different annihilation parameters may be chosen for different final states and different annihilation topologies. If so, the predictive power of the QCD factorization method may be rather limited for many decay channels.
|
hep-ph/0703306
|
Alexei Nefediev
|
A.V.Nefediev, Yu.A.Simonov (ITEP, Moscow)
|
Nonperturbative dynamics in the colour-magnetic QCD vacuum
|
LaTeX2e, 12 pages
|
Phys.Atom.Nucl.71:171-179,2008
|
10.1007/s11450-008-1018-7
| null |
hep-ph
| null |
In the deconfinement phase of QCD quarks and gluons interact with the dense
stochastic colour-magnetic vacuum. We consider the dynamics of quarks in this
deconfinement phase using the Field Correlators Method and derive an effective
nonperturbative inter-quark potential, in addition to the usual perturbative
short-ranged interaction. We find the resulting angular-momentum-dependent
interaction to be attractive enough to maintain bound states and, for light
quarks (and gluons), to cause emission of quark and gluon pairs. Possible
consequences for the strong interacting quark--gluon plasma are briefly
discussed.
|
[
{
"created": "Thu, 29 Mar 2007 09:57:44 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Nefediev",
"A. V.",
"",
"ITEP, Moscow"
],
[
"Simonov",
"Yu. A.",
"",
"ITEP, Moscow"
]
] |
In the deconfinement phase of QCD quarks and gluons interact with the dense stochastic colour-magnetic vacuum. We consider the dynamics of quarks in this deconfinement phase using the Field Correlators Method and derive an effective nonperturbative inter-quark potential, in addition to the usual perturbative short-ranged interaction. We find the resulting angular-momentum-dependent interaction to be attractive enough to maintain bound states and, for light quarks (and gluons), to cause emission of quark and gluon pairs. Possible consequences for the strong interacting quark--gluon plasma are briefly discussed.
|
0909.3555
|
Qing-Hong Cao
|
Edmond L. Berger and Qing-Hong Cao
|
Next-to-Leading Order Cross Sections for New Heavy Fermion Production at
Hadron Colliders
|
Phys. Rev. D Version
|
Phys.Rev.D81:035006,2010
|
10.1103/PhysRevD.81.035006
|
ANL-HEP-PR-09-93, EFI-09-24
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We evaluate the cross sections for new heavy fermion production at three
Large Hadron Collider energies accurate to next-to-leading order in
perturbative quantum chromodynamics. We treat the cases of pair production of
heavy quarks via strong interactions, single heavy quark production via
electroweak interactions, and the production of heavy leptons. Theoretical
uncertainties associated with the choice of the renormalization scale and the
parton distribution functions are specified. We derive a simple and useful
parameterization of our results which should facilitate phenomenological
studies of new physics models that predict new heavy quarks and/or leptons.
|
[
{
"created": "Sat, 19 Sep 2009 15:05:06 GMT",
"version": "v1"
},
{
"created": "Tue, 11 May 2010 14:29:22 GMT",
"version": "v2"
}
] |
2015-03-13
|
[
[
"Berger",
"Edmond L.",
""
],
[
"Cao",
"Qing-Hong",
""
]
] |
We evaluate the cross sections for new heavy fermion production at three Large Hadron Collider energies accurate to next-to-leading order in perturbative quantum chromodynamics. We treat the cases of pair production of heavy quarks via strong interactions, single heavy quark production via electroweak interactions, and the production of heavy leptons. Theoretical uncertainties associated with the choice of the renormalization scale and the parton distribution functions are specified. We derive a simple and useful parameterization of our results which should facilitate phenomenological studies of new physics models that predict new heavy quarks and/or leptons.
|
1112.0084
|
Ryusuke Jinno
|
Ryusuke Jinno, Takeo Moroi, Kazunori Nakayama
|
Imprints of Cosmic Phase Transition in Inflationary Gravitational Waves
|
4 pages, 2 figures
| null |
10.1016/j.physletb.2012.05.061
|
UT-11-40
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss the effects of cosmic phase transition on the spectrum of
primordial gravitational waves generated during inflation. The energy density
of the scalar condensation responsible for the phase transition may become
sizable at the epoch of phase transition, which significantly affects the
evolution of the universe. As a result, the amplitudes of the gravitational
waves at high frequency modes are suppressed. Thus the gravitational wave
spectrum can be a probe of phase transition in the early universe.
|
[
{
"created": "Thu, 1 Dec 2011 05:34:18 GMT",
"version": "v1"
}
] |
2015-06-03
|
[
[
"Jinno",
"Ryusuke",
""
],
[
"Moroi",
"Takeo",
""
],
[
"Nakayama",
"Kazunori",
""
]
] |
We discuss the effects of cosmic phase transition on the spectrum of primordial gravitational waves generated during inflation. The energy density of the scalar condensation responsible for the phase transition may become sizable at the epoch of phase transition, which significantly affects the evolution of the universe. As a result, the amplitudes of the gravitational waves at high frequency modes are suppressed. Thus the gravitational wave spectrum can be a probe of phase transition in the early universe.
|
hep-ph/9610300
| null |
K.C. Chou (CAS) and Yue-Liang Wu (OSU)
|
A solution to the puzzles of CP violation, neutrino oscillation, fermion
masses and mixings in an SUSY GUT model with small $tan \beta$
|
4 pages, latex, no figures, talk presented at SUSY96, May 1996,
University of Maryland
|
Nucl.Phys.Proc.Suppl. 52A (1997) 159-162
|
10.1016/S0920-5632(96)00553-1
|
DOE-ER-01545-675
|
hep-ph
| null |
CP violation, fermion masses and mixing angles including that of neutrinos
are studied in an SUSY SO(10)$\times \Delta(48) \times$ U(1) model with small
$tan \beta$. It is amazing that the model can provide a successful prediction
on twenty three observables by only using four parameters. The renormalization
group (RG) effects containing those above the GUT scale are considered. Fifteen
relations among the low energy parameters are found with nine of them free from
RG modifications. They could be tested directly by low energy experiments.
|
[
{
"created": "Wed, 9 Oct 1996 15:06:42 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Chou",
"K. C.",
"",
"CAS"
],
[
"Wu",
"Yue-Liang",
"",
"OSU"
]
] |
CP violation, fermion masses and mixing angles including that of neutrinos are studied in an SUSY SO(10)$\times \Delta(48) \times$ U(1) model with small $tan \beta$. It is amazing that the model can provide a successful prediction on twenty three observables by only using four parameters. The renormalization group (RG) effects containing those above the GUT scale are considered. Fifteen relations among the low energy parameters are found with nine of them free from RG modifications. They could be tested directly by low energy experiments.
|
1006.0710
|
Pierpaolo Mastrolia
|
P. Mastrolia, G. Ossola, T. Reiter, and F. Tramontano
|
Scattering AMplitudes from Unitarity-based Reduction Algorithm at the
Integrand-level
|
35 pages, 7 figures
|
JHEP 1008:080,2010
|
10.1007/JHEP08(2010)080
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
SAMURAI is a tool for the automated numerical evaluation of one-loop
corrections to any scattering amplitudes within the dimensional-regularization
scheme. It is based on the decomposition of the integrand according to the
OPP-approach, extended to accommodate an implementation of the generalized
d-dimensional unitarity-cuts technique, and uses a polynomial interpolation
exploiting the Discrete Fourier Transform. SAMURAI can process integrands
written either as numerator of Feynman diagrams or as product of tree-level
amplitudes. We discuss some applications, among which the 6- and 8-photon
scattering in QED, and the 6-quark scattering in QCD. SAMURAI has been
implemented as a Fortran90 library, publicly available, and it could be a
useful module for the systematic evaluation of the virtual corrections oriented
towards automating next-to-leading order calculations relevant for the LHC
phenomenology.
|
[
{
"created": "Thu, 3 Jun 2010 18:01:52 GMT",
"version": "v1"
}
] |
2014-11-21
|
[
[
"Mastrolia",
"P.",
""
],
[
"Ossola",
"G.",
""
],
[
"Reiter",
"T.",
""
],
[
"Tramontano",
"F.",
""
]
] |
SAMURAI is a tool for the automated numerical evaluation of one-loop corrections to any scattering amplitudes within the dimensional-regularization scheme. It is based on the decomposition of the integrand according to the OPP-approach, extended to accommodate an implementation of the generalized d-dimensional unitarity-cuts technique, and uses a polynomial interpolation exploiting the Discrete Fourier Transform. SAMURAI can process integrands written either as numerator of Feynman diagrams or as product of tree-level amplitudes. We discuss some applications, among which the 6- and 8-photon scattering in QED, and the 6-quark scattering in QCD. SAMURAI has been implemented as a Fortran90 library, publicly available, and it could be a useful module for the systematic evaluation of the virtual corrections oriented towards automating next-to-leading order calculations relevant for the LHC phenomenology.
|
2402.06209
|
Zuowei Liu
|
Zuowei Liu, Zi-Wei Tang
|
Probing ultralight isospin-violating mediators at GW170817
|
26 pages, 12 figures. v2: version accepted for publication in JHEP
| null | null | null |
hep-ph astro-ph.HE gr-qc
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Gravitational wave (GW) signals arising from binary neutron star mergers
offer new, sensitive probes to ultralight mediators. Here we analyze the GW
signals in the GW170817 event detected by the LIGO/Virgo collaboration to
impose constraints on the ultralight isospin-violating mediator that has
different couplings to protons and neutrons. Neutron stars, which primarily
consist of neutrons, are the ideal places to probe the isospin-violating
mediator. Such a mediator can significantly alter the dynamics of the binary
neutron star mergers, through both the long-range Yukawa force and the new
dipole radiation. We compute the gravitational waveform by taking into account
the new physics effects due to the isospin-violating mediator and use the
Bayesian inference to analyze the gravitational wave data in the GW170817
event. We find that although the current fifth force experiments (including
MICROSCOPE and EW) often provide more stringent constraints than the GW170817
data, in the parameter space where the isospin-violating force is completely
screened by the Earth (namely, the Earth is charge neutral under this force),
the GW170817 data offer the leading constraints: the upper bound on the neutron
coupling is $f_n \lesssim 10^{-19}$ in the mediator mass range of
$\simeq(3\times10^{-16},\,5\times10^{-14})$ eV.
|
[
{
"created": "Fri, 9 Feb 2024 06:27:44 GMT",
"version": "v1"
},
{
"created": "Sun, 19 May 2024 07:01:26 GMT",
"version": "v2"
}
] |
2024-05-21
|
[
[
"Liu",
"Zuowei",
""
],
[
"Tang",
"Zi-Wei",
""
]
] |
Gravitational wave (GW) signals arising from binary neutron star mergers offer new, sensitive probes to ultralight mediators. Here we analyze the GW signals in the GW170817 event detected by the LIGO/Virgo collaboration to impose constraints on the ultralight isospin-violating mediator that has different couplings to protons and neutrons. Neutron stars, which primarily consist of neutrons, are the ideal places to probe the isospin-violating mediator. Such a mediator can significantly alter the dynamics of the binary neutron star mergers, through both the long-range Yukawa force and the new dipole radiation. We compute the gravitational waveform by taking into account the new physics effects due to the isospin-violating mediator and use the Bayesian inference to analyze the gravitational wave data in the GW170817 event. We find that although the current fifth force experiments (including MICROSCOPE and EW) often provide more stringent constraints than the GW170817 data, in the parameter space where the isospin-violating force is completely screened by the Earth (namely, the Earth is charge neutral under this force), the GW170817 data offer the leading constraints: the upper bound on the neutron coupling is $f_n \lesssim 10^{-19}$ in the mediator mass range of $\simeq(3\times10^{-16},\,5\times10^{-14})$ eV.
|
1707.03598
|
Lu Meng
|
Lu Meng, Ning Li, Shi-lin Zhu
|
Possible hadronic molecules composed of the doubly charmed baryon and
nucleon
|
14 pages, 5 figures
| null |
10.1140/epja/i2018-12578-2
| null |
hep-ph hep-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We perform a systematical investigation of the possible deuteron-like bound
states with configuration $\Xi_{cc}N (\bar{N})$, where $N(\bar{N})$ denotes the
nucleon (anti-nucleon), in the framework of the one-boson-exchange-potential
model. In the spin-triplet sector we take into account both the ${}^3S_1$ and
${}^3D_1$ channels due to non-vanishing tensor force. There exist several
candidates of the loosely bound molecular states for the $\Xi_{cc}N$ and
$\Xi_{cc}\bar{N}$ systems, which lie below the threshold of
$\Lambda_c\Lambda_c$ or $\Lambda_c{\bar\Lambda}_c$. We also investigate the
possible loosely bound states with configurations $\Lambda_cN(\bar{N})$ and
$\Sigma_cN(\bar{N})$. These molecular candidates may be searched for at Belle
II and LHC in the near future.
|
[
{
"created": "Wed, 12 Jul 2017 08:44:05 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Aug 2018 00:55:08 GMT",
"version": "v2"
}
] |
2018-08-31
|
[
[
"Meng",
"Lu",
""
],
[
"Li",
"Ning",
""
],
[
"Zhu",
"Shi-lin",
""
]
] |
We perform a systematical investigation of the possible deuteron-like bound states with configuration $\Xi_{cc}N (\bar{N})$, where $N(\bar{N})$ denotes the nucleon (anti-nucleon), in the framework of the one-boson-exchange-potential model. In the spin-triplet sector we take into account both the ${}^3S_1$ and ${}^3D_1$ channels due to non-vanishing tensor force. There exist several candidates of the loosely bound molecular states for the $\Xi_{cc}N$ and $\Xi_{cc}\bar{N}$ systems, which lie below the threshold of $\Lambda_c\Lambda_c$ or $\Lambda_c{\bar\Lambda}_c$. We also investigate the possible loosely bound states with configurations $\Lambda_cN(\bar{N})$ and $\Sigma_cN(\bar{N})$. These molecular candidates may be searched for at Belle II and LHC in the near future.
|
1504.00823
|
Piotr Kotko
|
Piotr Kotko, Wojciech Slominski, Dawid Toton
|
Unintegrated gluon distributions for forward jets at LHC
|
18 pages, 6 figures; small corrections in the text and references
| null |
10.5506/APhysPolB.46.1527
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We test several BFKL-like evolution equations for unintegrated gluon
distributions against forward-central dijet production at LHC. Our study is
based on fitting the evolution scenarios to the LHC data using the high energy
factorization approach. Thus, as a by-product, we obtain a set of LHC-motivated
unintegrated gluon distributions ready to use. We utilize this application by
calculating azimuthal decorrelations for forward-central dijet production and
compare with existing data.
|
[
{
"created": "Fri, 3 Apr 2015 11:51:16 GMT",
"version": "v1"
},
{
"created": "Tue, 26 May 2015 19:55:07 GMT",
"version": "v2"
}
] |
2015-10-28
|
[
[
"Kotko",
"Piotr",
""
],
[
"Slominski",
"Wojciech",
""
],
[
"Toton",
"Dawid",
""
]
] |
We test several BFKL-like evolution equations for unintegrated gluon distributions against forward-central dijet production at LHC. Our study is based on fitting the evolution scenarios to the LHC data using the high energy factorization approach. Thus, as a by-product, we obtain a set of LHC-motivated unintegrated gluon distributions ready to use. We utilize this application by calculating azimuthal decorrelations for forward-central dijet production and compare with existing data.
|
hep-ph/0208036
|
Yoshimasa Kurihara
|
J. Fujimoto, et al
|
GRACE/SUSY Automatic Generation of Tree Amplitudes in the Minimal
Supersymmetric Standard Model
|
39 page, 1 figure
|
Comput.Phys.Commun. 153 (2003) 106-134
|
10.1016/S0010-4655(03)00159-0
|
KEK-CP-129
|
hep-ph
| null |
GRACE/SUSY is a program package for generating the tree-level amplitude and
evaluating the corresponding cross section of processes of the minimal
supersymmetric extension of the standard model (MSSM). The Higgs potential
adopted in the system, however, is assumed to have a more general form
indicated by the two-Higgs-doublet model. This system is an extension of GRACE
for the standard model(SM) of the electroweak and strong interactions. For a
given MSSM process the Feynman graphs and amplitudes at tree-level are
automatically created. The Monte-Carlo phase space integration by means of
BASES gives the total and differential cross sections. When combined with
SPRING, an event generator, the program package provides us with the simulation
of the SUSY particle productions.
|
[
{
"created": "Mon, 5 Aug 2002 05:18:50 GMT",
"version": "v1"
}
] |
2009-11-07
|
[
[
"Fujimoto",
"J.",
""
]
] |
GRACE/SUSY is a program package for generating the tree-level amplitude and evaluating the corresponding cross section of processes of the minimal supersymmetric extension of the standard model (MSSM). The Higgs potential adopted in the system, however, is assumed to have a more general form indicated by the two-Higgs-doublet model. This system is an extension of GRACE for the standard model(SM) of the electroweak and strong interactions. For a given MSSM process the Feynman graphs and amplitudes at tree-level are automatically created. The Monte-Carlo phase space integration by means of BASES gives the total and differential cross sections. When combined with SPRING, an event generator, the program package provides us with the simulation of the SUSY particle productions.
|
hep-ph/0308263
|
Matthias Lutz F. M.
|
J. Hofmann and M.F.M. Lutz (GSI, Darmstadt)
|
Open-charm meson resonances with negative strangeness
|
12 pages, 3 figures
|
Nucl.Phys.A733:142-152,2004
|
10.1016/j.nuclphysa.2003.12.013
|
GSI-Preprint-2003-29
|
hep-ph
| null |
We study heavy-light meson resonances with quantum numbers J^P=0^+ and
J^P=1^+ in terms of the non-linear chiral SU(3) Lagrangian. Adjusting the free
parameters that arise at subleading order to reproduce the mass of the D(2420)
resonance as well as the new states established recently by the BABAR, CLEO and
BELLE collaborations we obtain refined masses for the anti-triplet and sextet
states. Bound states of antikaons at the D(1867) and D(2008) mesons are
predicted at 2352 MeV (J^P=0^+) and 2416 MeV (J^P=1^+). In addition we
anticipate a narrow scalar state of mass 2389 MeV with (I,S)=(1/2,0)
|
[
{
"created": "Tue, 26 Aug 2003 14:57:19 GMT",
"version": "v1"
}
] |
2010-12-16
|
[
[
"Hofmann",
"J.",
"",
"GSI, Darmstadt"
],
[
"Lutz",
"M. F. M.",
"",
"GSI, Darmstadt"
]
] |
We study heavy-light meson resonances with quantum numbers J^P=0^+ and J^P=1^+ in terms of the non-linear chiral SU(3) Lagrangian. Adjusting the free parameters that arise at subleading order to reproduce the mass of the D(2420) resonance as well as the new states established recently by the BABAR, CLEO and BELLE collaborations we obtain refined masses for the anti-triplet and sextet states. Bound states of antikaons at the D(1867) and D(2008) mesons are predicted at 2352 MeV (J^P=0^+) and 2416 MeV (J^P=1^+). In addition we anticipate a narrow scalar state of mass 2389 MeV with (I,S)=(1/2,0)
|
hep-ph/9310260
|
Dudas
|
E.A. Dudas
|
Planck Scale Effects and Axions in Supersymmetry
|
12 pages, LPTHE Orsay 93/35
|
Phys.Lett.B325:124-128,1994
|
10.1016/0370-2693(94)90081-7
| null |
hep-ph
| null |
The effects of possible explicit violation of the Peccei-Quinn symmetry
responsible for the solution of the strong CP problem are studied in
supersymmetric models. It is shown that automatic models with an abelian $U(1)$
gauge symmetry are easy to construct both in the context of fundamental and
composite models of axions. It is argued that it is preferable to use abelian
rather than nonabelian gauge groups in order to obtains automatic symmetries. A
composite model with no exact $R$ symmetry is studied and it is found that,
unlike common belief, supersymmetry is broken.
|
[
{
"created": "Mon, 11 Oct 1993 14:01:20 GMT",
"version": "v1"
}
] |
2010-11-01
|
[
[
"Dudas",
"E. A.",
""
]
] |
The effects of possible explicit violation of the Peccei-Quinn symmetry responsible for the solution of the strong CP problem are studied in supersymmetric models. It is shown that automatic models with an abelian $U(1)$ gauge symmetry are easy to construct both in the context of fundamental and composite models of axions. It is argued that it is preferable to use abelian rather than nonabelian gauge groups in order to obtains automatic symmetries. A composite model with no exact $R$ symmetry is studied and it is found that, unlike common belief, supersymmetry is broken.
|
hep-ph/9411232
|
Johan Bijnens
|
J. Bijnens, G. Ecker and J. Gasser
|
Chiral Perturbation Theory
|
19 pages, latex, 2 figures. To be published in the second edition of
the DA$\Phi$NE Physics Handbook, eds. L. Maiani, G. Pancheri and N. Paver.
| null | null | null |
hep-ph
| null |
An introduction to Chiral Perturbation Theory is given including a discussion
of power counting, the Wess-Zumino term, the values of the coupling constants
and the inclusion of the effects of other resonances.
|
[
{
"created": "Mon, 7 Nov 1994 10:28:14 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Bijnens",
"J.",
""
],
[
"Ecker",
"G.",
""
],
[
"Gasser",
"J.",
""
]
] |
An introduction to Chiral Perturbation Theory is given including a discussion of power counting, the Wess-Zumino term, the values of the coupling constants and the inclusion of the effects of other resonances.
|
1307.1064
|
R. Sekhar Chivukula
|
R. Sekhar Chivukula, Arsham Farzinnia, Jing Ren, and Elizabeth H.
Simmons
|
Constraints on the Scalar Sector of the Renormalizable Coloron Model
|
20 pages, pdf included figures. Brief phenomenological analysis of
additional scalar s-boson added. Erratum appended: an error in the
Higgs-boson gluon-fusion production amplitude arising from the new colored
states is corrected, resulting in stronger constraints on the model parameter
space
|
Phys. Rev. D 88, 075020 (2013)
|
10.1103/PhysRevD.88.075020
|
MSUHEP-130703
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The renormalizable coloron model is the minimal extension of the standard
model color sector, in which the color gauge group is enlarged to SU(3)_{1c} x
SU(3)_{2c}. In this paper we discuss the constraints on this model derived from
the requirements of vacuum stability, tree-level unitarity, electroweak
precision measurements, and from LHC measurements of the properties of the
observed Higgs-like scalar boson. The combination of these theoretical and
experimental considerations strongly constrains the allowed parameter space.
(Erratum appended, March 2014.)
|
[
{
"created": "Wed, 3 Jul 2013 16:16:59 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Jul 2013 17:41:09 GMT",
"version": "v2"
},
{
"created": "Fri, 4 Oct 2013 12:24:57 GMT",
"version": "v3"
},
{
"created": "Wed, 5 Mar 2014 01:09:12 GMT",
"version": "v4"
}
] |
2014-03-06
|
[
[
"Chivukula",
"R. Sekhar",
""
],
[
"Farzinnia",
"Arsham",
""
],
[
"Ren",
"Jing",
""
],
[
"Simmons",
"Elizabeth H.",
""
]
] |
The renormalizable coloron model is the minimal extension of the standard model color sector, in which the color gauge group is enlarged to SU(3)_{1c} x SU(3)_{2c}. In this paper we discuss the constraints on this model derived from the requirements of vacuum stability, tree-level unitarity, electroweak precision measurements, and from LHC measurements of the properties of the observed Higgs-like scalar boson. The combination of these theoretical and experimental considerations strongly constrains the allowed parameter space. (Erratum appended, March 2014.)
|
hep-ph/0006306
|
Eric S. Swanson
|
Adam P. Szczepaniak (Indiana University) and Eric S. Swanson
(University of Pittsburgh)
|
Chiral Extrapolation, Renormalization, and the Viability of the Quark
Model
|
6 pages, 2 eps figures, uses revtex. Version to appear in Phys. Rev.
Lett
|
Phys.Rev.Lett. 87 (2001) 072001
|
10.1103/PhysRevLett.87.072001
| null |
hep-ph
| null |
The relationship of the quark model to the known chiral properties of QCD is
a longstanding problem in the interpretation of low energy QCD. In particular,
how can the pion be viewed as both a collective Goldstone boson quasiparticle
and as a valence quark antiquark bound state where universal hyperfine
interactions govern spin splittings in the same way as in the heavy quark
systems. We address this issue in a simplified model which; however, reproduces
all features of QCD relevant to this problem. A comparison of the many-body
solution to our model and the constituent quark model demonstrates that the
quark model is sufficiently flexible to describe meson hyperfine splitting
provided proper renormalization conditions and correct degrees of freedom are
employed consistently.
|
[
{
"created": "Tue, 27 Jun 2000 15:30:04 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Jun 2001 20:20:03 GMT",
"version": "v2"
}
] |
2009-10-31
|
[
[
"Szczepaniak",
"Adam P.",
"",
"Indiana University"
],
[
"Swanson",
"Eric S.",
"",
"University of Pittsburgh"
]
] |
The relationship of the quark model to the known chiral properties of QCD is a longstanding problem in the interpretation of low energy QCD. In particular, how can the pion be viewed as both a collective Goldstone boson quasiparticle and as a valence quark antiquark bound state where universal hyperfine interactions govern spin splittings in the same way as in the heavy quark systems. We address this issue in a simplified model which; however, reproduces all features of QCD relevant to this problem. A comparison of the many-body solution to our model and the constituent quark model demonstrates that the quark model is sufficiently flexible to describe meson hyperfine splitting provided proper renormalization conditions and correct degrees of freedom are employed consistently.
|
hep-ph/9506291
|
Jan Kalinowski
|
J. Kalinowski and M. Krawczyk (Institute of Theoretical Physics,
Warsaw University)
|
Fermion mass effects on ${\Gamma(Z\ra b\bar{b} + a~light~Higgs)}$ in a
two-Higgs-doublet model
|
LaTeX file, 4 pages, 3 figures (in postscript) in a separate file
|
Phys.Lett. B361 (1995) 66-68
|
10.1016/0370-2693(95)01102-V
|
IFT/95/6
|
hep-ph
| null |
Large fermion mass effect on the Yukawa process $Z \ra b\bar{b}\ra b\bar{b} h
(A)$ in the entire range of the neutral Higgs boson masses is found. It is
particularly important for light Higgs bosons, which are still not excluded
experimentally in a general two-Higgs-doublet model.
|
[
{
"created": "Sun, 11 Jun 1995 10:01:05 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Kalinowski",
"J.",
"",
"Institute of Theoretical Physics,\n Warsaw University"
],
[
"Krawczyk",
"M.",
"",
"Institute of Theoretical Physics,\n Warsaw University"
]
] |
Large fermion mass effect on the Yukawa process $Z \ra b\bar{b}\ra b\bar{b} h (A)$ in the entire range of the neutral Higgs boson masses is found. It is particularly important for light Higgs bosons, which are still not excluded experimentally in a general two-Higgs-doublet model.
|
hep-ph/9811335
|
Dan Pirjol
|
Michael Gronau and Dan Pirjol
|
Weak phases $\gamma$ and $\alpha$ from $B^+$, or $B^0$ and $B_s$ decays
|
9 pages with 2 included eps figures; revised argument, taking into
account the special shape of the amplitude quadrangle. An improved bound on
rescattering effects is given
|
Phys.Lett.B449:321-327,1999
|
10.1016/S0370-2693(99)00083-0
|
CLNS 98/1591, TECHNION-PH-98-92
|
hep-ph
| null |
An improved flavor SU(3) method is presented for determining the weak angle
$\gamma$ of the unitarity triangle using decay rates for $B^+\to K\pi, B^+\to
K^+\bar K^0$ and $B^+\to \pi^+\eta$ (or $B^0\to K\pi$ and $B_s\to K \pi$),
their CP-conjugate modes and the CP-averaged rate for $B^\pm\to\pi^\pm\pi^{0}$.
Rescattering (color-suppressed) contribution in $B^+(B^0)\to K\pi$, for which
an improved bound is obtained, is subtracted away. The only significant SU(3)
breaking effects are accounted for in the factorization approximation of tree
amplitudes. The weak angle $\alpha$ is obtained as a byproduct.
|
[
{
"created": "Sun, 15 Nov 1998 18:11:52 GMT",
"version": "v1"
},
{
"created": "Sun, 29 Nov 1998 22:33:51 GMT",
"version": "v2"
}
] |
2014-11-17
|
[
[
"Gronau",
"Michael",
""
],
[
"Pirjol",
"Dan",
""
]
] |
An improved flavor SU(3) method is presented for determining the weak angle $\gamma$ of the unitarity triangle using decay rates for $B^+\to K\pi, B^+\to K^+\bar K^0$ and $B^+\to \pi^+\eta$ (or $B^0\to K\pi$ and $B_s\to K \pi$), their CP-conjugate modes and the CP-averaged rate for $B^\pm\to\pi^\pm\pi^{0}$. Rescattering (color-suppressed) contribution in $B^+(B^0)\to K\pi$, for which an improved bound is obtained, is subtracted away. The only significant SU(3) breaking effects are accounted for in the factorization approximation of tree amplitudes. The weak angle $\alpha$ is obtained as a byproduct.
|
0901.4200
|
C\'edric Lorc\'e
|
C\'edric Lorc\'e
|
Electromagnetic Properties for Arbitrary Spin Particles: Part 2 $-$
Natural Moments and Transverse Charge Densities
|
12 pages, 1 table
|
Phys.Rev.D79:113011,2009
|
10.1103/PhysRevD.79.113011
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In a set of two papers, we propose to study an old-standing problem, namely
the electromagnetic interaction for particles of arbitrary spin. Based on the
assumption that light-cone helicity at tree level and $Q^2=0$ should be
conserved non-trivially by the electromagnetic interaction, we are able to
derive \emph{all} the natural electromagnetic moments for a pointlike particle
of \emph{any} spin. In this second paper, we give explicit expressions for the
light-cone helicity amplitudes in terms of covariant vertex functions, leading
to the natural electromagnetic moments at $Q^2=0$. As an application of our
results, we generalize the discussion of quark transverse charge densities to
particles with arbitrary spin.
|
[
{
"created": "Tue, 27 Jan 2009 09:02:24 GMT",
"version": "v1"
}
] |
2010-04-15
|
[
[
"Lorcé",
"Cédric",
""
]
] |
In a set of two papers, we propose to study an old-standing problem, namely the electromagnetic interaction for particles of arbitrary spin. Based on the assumption that light-cone helicity at tree level and $Q^2=0$ should be conserved non-trivially by the electromagnetic interaction, we are able to derive \emph{all} the natural electromagnetic moments for a pointlike particle of \emph{any} spin. In this second paper, we give explicit expressions for the light-cone helicity amplitudes in terms of covariant vertex functions, leading to the natural electromagnetic moments at $Q^2=0$. As an application of our results, we generalize the discussion of quark transverse charge densities to particles with arbitrary spin.
|
0806.3043
|
Grigorios Chachamis
|
G. Chachamis, M. Czakon, D. Eiras
|
W Pair Production at the LHC - II. One-loop Squared Corrections in the
High Energy Limit
|
12 pages
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present the result for the one-loop squared virtual QCD corrections to the
W boson pair production in the quark-anti-quark-annihilation channel in the
limit where all kinematical invariants are large compared to the mass of the W
boson. The infrared pole structure is in agreement with the prediction of
Catani's general formalism for the singularities of QCD amplitudes.
|
[
{
"created": "Wed, 18 Jun 2008 16:54:18 GMT",
"version": "v1"
}
] |
2008-06-19
|
[
[
"Chachamis",
"G.",
""
],
[
"Czakon",
"M.",
""
],
[
"Eiras",
"D.",
""
]
] |
We present the result for the one-loop squared virtual QCD corrections to the W boson pair production in the quark-anti-quark-annihilation channel in the limit where all kinematical invariants are large compared to the mass of the W boson. The infrared pole structure is in agreement with the prediction of Catani's general formalism for the singularities of QCD amplitudes.
|
hep-ph/0312045
|
Frank E. Paige
|
Howard Baer, Frank E. Paige, Serban D. Protopescu, and Xerxes Tata
|
ISAJET 7.69: A Monte Carlo Event Generator for pp, $\bar pp$, and
$e^=e^-$ Reactions
|
95 pages, no figures
| null | null | null |
hep-ph
| null |
ISAJET 7.69 is now available, replacing version 7.64 and several intermediate
versions. This document contains the release notes and current manual.
|
[
{
"created": "Wed, 3 Dec 2003 11:02:23 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Baer",
"Howard",
""
],
[
"Paige",
"Frank E.",
""
],
[
"Protopescu",
"Serban D.",
""
],
[
"Tata",
"Xerxes",
""
]
] |
ISAJET 7.69 is now available, replacing version 7.64 and several intermediate versions. This document contains the release notes and current manual.
|
2405.07036
|
Lei Meng
|
Lei Meng, Junjie Cao, Fei Li, and Shenshen Yang
|
Dark Matter Physics in General NMSSM
|
44 pages, 8 tables, 6 figures
| null | null | null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
In the General Next-to-Minimal Supersymmetric Standard Model (GNMSSM),
singlet particles may form a secluded sector of dark matter (DM), in which
Singlino-like DM could achieve the observed relic abundance through various
channels such as $\tilde{\chi}_1^0 \tilde{\chi}_1^0 \to h_s h_s, A_s A_s, h_s
A_s$, where $h_s$ and $A_s$ represent singlet-dominated CP-even and CP-odd
Higgs bosons. We provide analytical formulas for both the spin-independent and
spin-dependent cross sections of Singlino DM scattering with nucleons,
illustrating their dependence on the model's parameters in a clear manner. We
also present analytic expressions for the annihilation cross sections of these
three important channels. Based on these preparations, we conducted Bayesian
analyses of the GNMSSM and concluded that the theory significantly favored
Singlino-dominated DM over Bino-like DM across a much broader range of
parameters. The combined results from our numerical analyses and the formulas
distinctly highlight crucial aspects of DM physics within the GNMSSM.
|
[
{
"created": "Sat, 11 May 2024 15:20:00 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Aug 2024 11:08:28 GMT",
"version": "v2"
}
] |
2024-08-16
|
[
[
"Meng",
"Lei",
""
],
[
"Cao",
"Junjie",
""
],
[
"Li",
"Fei",
""
],
[
"Yang",
"Shenshen",
""
]
] |
In the General Next-to-Minimal Supersymmetric Standard Model (GNMSSM), singlet particles may form a secluded sector of dark matter (DM), in which Singlino-like DM could achieve the observed relic abundance through various channels such as $\tilde{\chi}_1^0 \tilde{\chi}_1^0 \to h_s h_s, A_s A_s, h_s A_s$, where $h_s$ and $A_s$ represent singlet-dominated CP-even and CP-odd Higgs bosons. We provide analytical formulas for both the spin-independent and spin-dependent cross sections of Singlino DM scattering with nucleons, illustrating their dependence on the model's parameters in a clear manner. We also present analytic expressions for the annihilation cross sections of these three important channels. Based on these preparations, we conducted Bayesian analyses of the GNMSSM and concluded that the theory significantly favored Singlino-dominated DM over Bino-like DM across a much broader range of parameters. The combined results from our numerical analyses and the formulas distinctly highlight crucial aspects of DM physics within the GNMSSM.
|
2209.10110
|
Dibyakrupa Sahoo
|
C. S. Kim, Janusz Rosiek and Dibyakrupa Sahoo
|
Probing the non-standard neutrino interactions using quantum statistics
|
15 pages, 6 figures, for the published version visit the DOI
|
Eur. Phys. J. C 83, 221 (2023)
|
10.1140/epjc/s10052-023-11355-8
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Using the well established principles of Lorentz invariance, CP and CPT
symmetry, and quantum statistics we do a model-independent study of effects of
possible non-standard couplings of (Dirac and Majorana) neutrinos. The study is
sensitive to the different quantum statistical properties of the Dirac and
Majorana neutrinos which, contrary to neutrino-mediated processes of lepton
number violation, could lead to observable effects not suppressed by the small
ratios of neutrino and heavier particle masses. For processes with a
neutrino-antineutrino pair of the same flavor in the final state, we formulate
the ``Dirac Majorana confusion theorem (DMCT)'' showing why it is normally very
difficult to observe the different behaviour of both kinds of neutrinos in
experiments if they have only the standard model (SM)-like left-handed vector
couplings to gauge bosons. We discuss deviations from the confusion theorem in
the presence of non-standard neutrino interactions, allowing to discover or
constrain such novel couplings. We illustrate the general results with two
chosen examples of neutral current processes, $Z \to \nu \, \overline{\nu}$ and
$\mathcal{P}_i \to \mathcal{P}_f \, \nu \, \overline{\nu}$ (with
$\mathcal{P}_{i,f}$ denoting pseudoscalar mesons, such as $B,K,\pi$). Our
analysis shows that using 3-body decays the presence of non-standard
interactions can not only be constrained but one can also distinguish between
Dirac and Majorana neutrino possibilities.
|
[
{
"created": "Mon, 19 Sep 2022 18:01:17 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Mar 2023 10:27:56 GMT",
"version": "v2"
}
] |
2023-03-28
|
[
[
"Kim",
"C. S.",
""
],
[
"Rosiek",
"Janusz",
""
],
[
"Sahoo",
"Dibyakrupa",
""
]
] |
Using the well established principles of Lorentz invariance, CP and CPT symmetry, and quantum statistics we do a model-independent study of effects of possible non-standard couplings of (Dirac and Majorana) neutrinos. The study is sensitive to the different quantum statistical properties of the Dirac and Majorana neutrinos which, contrary to neutrino-mediated processes of lepton number violation, could lead to observable effects not suppressed by the small ratios of neutrino and heavier particle masses. For processes with a neutrino-antineutrino pair of the same flavor in the final state, we formulate the ``Dirac Majorana confusion theorem (DMCT)'' showing why it is normally very difficult to observe the different behaviour of both kinds of neutrinos in experiments if they have only the standard model (SM)-like left-handed vector couplings to gauge bosons. We discuss deviations from the confusion theorem in the presence of non-standard neutrino interactions, allowing to discover or constrain such novel couplings. We illustrate the general results with two chosen examples of neutral current processes, $Z \to \nu \, \overline{\nu}$ and $\mathcal{P}_i \to \mathcal{P}_f \, \nu \, \overline{\nu}$ (with $\mathcal{P}_{i,f}$ denoting pseudoscalar mesons, such as $B,K,\pi$). Our analysis shows that using 3-body decays the presence of non-standard interactions can not only be constrained but one can also distinguish between Dirac and Majorana neutrino possibilities.
|
hep-ph/0102314
|
Koshiro Suzuki
|
Koshiro Suzuki and T.Watari
|
Constraints on Inflation Models from Supersymmetry Breakings
|
12 pages, 1 ps figure, minor correction
|
Phys.Lett. B506 (2001) 231-237
|
10.1016/S0370-2693(01)00412-9
| null |
hep-ph
| null |
Effects of soft SUSY-breaking terms on inflation potentials are discussed.
There exist generic constraints that must be satisfied in order not for the
inflaton potential to loose its flatness. We examine explicitly the constraints
in the case of a hybrid inflation model and find that the coupling constant
\lambda between the inflaton and the ``water-fall-direction'' field is bounded
as 2.0 \times 10^{-6} < \lambda. This is a highly non-trivial result. Indeed,
if we adopt the severest constraint from avoiding the problem of the gravitinos
produced non-thermally, \lambda < 7.4 \times 10^{-6} is required, under a
reasonable assumption on the reheating process. This means that the hybrid
inflation model marginally has a viable parameter space. We also discuss
analogous constraints on other inflation models.
|
[
{
"created": "Mon, 26 Feb 2001 14:23:52 GMT",
"version": "v1"
},
{
"created": "Tue, 27 Feb 2001 04:43:42 GMT",
"version": "v2"
}
] |
2009-11-07
|
[
[
"Suzuki",
"Koshiro",
""
],
[
"Watari",
"T.",
""
]
] |
Effects of soft SUSY-breaking terms on inflation potentials are discussed. There exist generic constraints that must be satisfied in order not for the inflaton potential to loose its flatness. We examine explicitly the constraints in the case of a hybrid inflation model and find that the coupling constant \lambda between the inflaton and the ``water-fall-direction'' field is bounded as 2.0 \times 10^{-6} < \lambda. This is a highly non-trivial result. Indeed, if we adopt the severest constraint from avoiding the problem of the gravitinos produced non-thermally, \lambda < 7.4 \times 10^{-6} is required, under a reasonable assumption on the reheating process. This means that the hybrid inflation model marginally has a viable parameter space. We also discuss analogous constraints on other inflation models.
|
1106.4147
|
Martin Hoferichter
|
Martin Hoferichter, Daniel R. Phillips, Carlos Schat
|
Roy-Steiner equations for gamma gamma -> pi pi
|
27 pages, 10 figures, version published in Eur.Phys.J. C
|
Eur.Phys.J. C 71 (2011) 1743
|
10.1140/epjc/s10052-011-1743-x
| null |
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Starting from hyperbolic dispersion relations, we derive a system of
Roy--Steiner equations for pion Compton scattering that respects analyticity,
unitarity, gauge invariance, and crossing symmetry. It thus maintains all
symmetries of the underlying quantum field theory. To suppress the dependence
of observables on high-energy input, we also consider once- and
twice-subtracted versions of the equations, and identify the subtraction
constants with dipole and quadrupole pion polarizabilities. Based on the
assumption of Mandelstam analyticity, we determine the kinematic range in which
the equations are valid. As an application, we consider the resolution of the
$\gamma\gamma\to\pi\pi$ partial waves by a Muskhelishvili--Omn\`es
representation with finite matching point. We find a sum rule for the
isospin-two $S$-wave, which, together with chiral constraints, produces an
improved prediction for the charged-pion quadrupole polarizability
$(\alpha_2-\beta_2)^{\pi^\pm}=(15.3\pm 3.7)\cdot 10^{-4} {\rm fm}^5$. We
investigate the prediction of our dispersion relations for the two-photon
coupling of the $\sigma$-resonance $\Gamma_{\sigma\gamma\gamma}$. The
twice-subtracted version predicts a correlation between this width and the
isospin-zero pion polarizabilities, which is largely independent of the
high-energy input used in the equations. Using this correlation, the chiral
perturbation theory results for pion polarizabilities, and our new sum rule, we
find $\Gamma_{\sigma\gamma\gamma}=(1.7\pm 0.4)\,{\rm keV}$.
|
[
{
"created": "Tue, 21 Jun 2011 09:36:55 GMT",
"version": "v1"
},
{
"created": "Sun, 25 Sep 2011 18:39:45 GMT",
"version": "v2"
}
] |
2011-09-27
|
[
[
"Hoferichter",
"Martin",
""
],
[
"Phillips",
"Daniel R.",
""
],
[
"Schat",
"Carlos",
""
]
] |
Starting from hyperbolic dispersion relations, we derive a system of Roy--Steiner equations for pion Compton scattering that respects analyticity, unitarity, gauge invariance, and crossing symmetry. It thus maintains all symmetries of the underlying quantum field theory. To suppress the dependence of observables on high-energy input, we also consider once- and twice-subtracted versions of the equations, and identify the subtraction constants with dipole and quadrupole pion polarizabilities. Based on the assumption of Mandelstam analyticity, we determine the kinematic range in which the equations are valid. As an application, we consider the resolution of the $\gamma\gamma\to\pi\pi$ partial waves by a Muskhelishvili--Omn\`es representation with finite matching point. We find a sum rule for the isospin-two $S$-wave, which, together with chiral constraints, produces an improved prediction for the charged-pion quadrupole polarizability $(\alpha_2-\beta_2)^{\pi^\pm}=(15.3\pm 3.7)\cdot 10^{-4} {\rm fm}^5$. We investigate the prediction of our dispersion relations for the two-photon coupling of the $\sigma$-resonance $\Gamma_{\sigma\gamma\gamma}$. The twice-subtracted version predicts a correlation between this width and the isospin-zero pion polarizabilities, which is largely independent of the high-energy input used in the equations. Using this correlation, the chiral perturbation theory results for pion polarizabilities, and our new sum rule, we find $\Gamma_{\sigma\gamma\gamma}=(1.7\pm 0.4)\,{\rm keV}$.
|
1110.2414
|
Genevieve Belanger
|
G. Belanger, J. Da Silva, A. Pukhov
|
The right-handed sneutrino as thermal dark matter in U(1) extensions of
the MSSM
|
29 pages, 12 figures
| null |
10.1088/1475-7516/2011/12/014
|
LAPTH-039/11
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate the parameter space of a supersymmetric model with an extended
U(1) gauge symmetry in which the RH sneutrino is a thermal dark matter
candidate. In this scenario, annihilation of RH sneutrinos proceeds mainly
through Higgs or Z' exchange. We find that sneutrinos in the mass range from
50GeV to more than 1 TeV can be consistent with both the WMAP limit and the
direct detection upper limits. Powerful constraints from new gauge boson
searches at the LHC as well as from $\Delta M_s$ are incorporated. Depending on
the choice of the U(1) charge, these scenarios will be further probe by direct
dark matter searches as well as by Higgs searches at the LHC.
|
[
{
"created": "Tue, 11 Oct 2011 16:14:00 GMT",
"version": "v1"
}
] |
2015-05-30
|
[
[
"Belanger",
"G.",
""
],
[
"Da Silva",
"J.",
""
],
[
"Pukhov",
"A.",
""
]
] |
We investigate the parameter space of a supersymmetric model with an extended U(1) gauge symmetry in which the RH sneutrino is a thermal dark matter candidate. In this scenario, annihilation of RH sneutrinos proceeds mainly through Higgs or Z' exchange. We find that sneutrinos in the mass range from 50GeV to more than 1 TeV can be consistent with both the WMAP limit and the direct detection upper limits. Powerful constraints from new gauge boson searches at the LHC as well as from $\Delta M_s$ are incorporated. Depending on the choice of the U(1) charge, these scenarios will be further probe by direct dark matter searches as well as by Higgs searches at the LHC.
|
hep-ph/9212248
| null |
J.R. Espinosa, M. Quiros and F. Zwirner
|
On the nature of the electroweak phase transition
|
13 pages, latex, 2 postscript figures appended at the end,
CERN-TH.6577/92, IEM-FT-58/92
|
Phys.Lett.B314:206-216,1993
|
10.1016/0370-2693(93)90450-V
| null |
hep-ph hep-th
| null |
We discuss the finite-temperature effective potential of the Standard Model,
$\veff$, with emphasis on the resummation of the most important infrared
contributions. We compute the one-loop scalar and vector boson self-energies in
the zero-momentum limit. By solving the corresponding set of gap equations,
with the inclusion of subleading contributions, we find a non-vanishing
magnetic mass for the $SU(2)$ gauge bosons. We comment on its possible
implications for the nature of the electroweak phase transition. We also
discuss the range of validity of our approximations and compare this with other
approaches.
|
[
{
"created": "Thu, 10 Dec 1992 14:27:57 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Dec 1992 10:01:05 GMT",
"version": "v2"
},
{
"created": "Thu, 14 Jan 1993 10:01:19 GMT",
"version": "v3"
},
{
"created": "Fri, 9 Jul 1993 15:44:20 GMT",
"version": "v4"
}
] |
2010-11-01
|
[
[
"Espinosa",
"J. R.",
""
],
[
"Quiros",
"M.",
""
],
[
"Zwirner",
"F.",
""
]
] |
We discuss the finite-temperature effective potential of the Standard Model, $\veff$, with emphasis on the resummation of the most important infrared contributions. We compute the one-loop scalar and vector boson self-energies in the zero-momentum limit. By solving the corresponding set of gap equations, with the inclusion of subleading contributions, we find a non-vanishing magnetic mass for the $SU(2)$ gauge bosons. We comment on its possible implications for the nature of the electroweak phase transition. We also discuss the range of validity of our approximations and compare this with other approaches.
|
2105.07077
|
Sebastian Trojanowski
|
Felix Kling, Sebastian Trojanowski
|
FORESEE: FORward Experiment SEnsitivity Estimator for the LHC and future
hadron colliders
|
11 pages, 3 figures, FORESEE code available at
https://github.com/KlingFelix/FORESEE
|
Phys. Rev. D 104, 035012 (2021)
|
10.1103/PhysRevD.104.035012
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We introduce a numerical package FORward Experiment SEnsitivity Estimator, or
FORESEE, that can be used to simulate the expected sensitivity reach of
experiments placed in the far-forward direction from the proton-proton
interaction point. The simulations can be performed for $14$ TeV collision
energy characteristic for the LHC, as well as for larger energies: $27$ and
$100$ TeV. In the package, a comprehensive list of validated forward spectra of
various SM species is also provided. The capabilities of FORESEE are
illustrated for the popular dark photon and dark Higgs boson models, as well as
for the search for light up-philic scalars. For the dark photon portal, we also
comment on the complementarity between such searches and dark matter direct
detection bounds. Additionally, for the first time, we discuss the prospects
for the LLP searches in the proposed future hadron colliders: High-Energy LHC
(HE-LHC), Super proton-proton Collider (SppC), and Future Circular Collider
(FCC-hh).
|
[
{
"created": "Fri, 14 May 2021 21:42:21 GMT",
"version": "v1"
}
] |
2021-08-25
|
[
[
"Kling",
"Felix",
""
],
[
"Trojanowski",
"Sebastian",
""
]
] |
We introduce a numerical package FORward Experiment SEnsitivity Estimator, or FORESEE, that can be used to simulate the expected sensitivity reach of experiments placed in the far-forward direction from the proton-proton interaction point. The simulations can be performed for $14$ TeV collision energy characteristic for the LHC, as well as for larger energies: $27$ and $100$ TeV. In the package, a comprehensive list of validated forward spectra of various SM species is also provided. The capabilities of FORESEE are illustrated for the popular dark photon and dark Higgs boson models, as well as for the search for light up-philic scalars. For the dark photon portal, we also comment on the complementarity between such searches and dark matter direct detection bounds. Additionally, for the first time, we discuss the prospects for the LLP searches in the proposed future hadron colliders: High-Energy LHC (HE-LHC), Super proton-proton Collider (SppC), and Future Circular Collider (FCC-hh).
|
2204.04834
|
Xuewen Liu
|
Xuewen Liu, Shu-Yuan Guo, Bin Zhu, Ying Li
|
Correlating Gravitational Waves with $W$-boson Mass, FIMP Dark Matter,
and Majorana Seesaw Mechanism
|
References updated, accepted for publication in Science Bulletin
|
Science Bulletin, 2022, 67(14): 1437-1442
|
10.1016/j.scib.2022.06.011
| null |
hep-ph
|
http://creativecommons.org/publicdomain/zero/1.0/
|
We study a minimal extension of the Standard Model by introducing three
right-handed neutrinos and a new scotogenic scalar doublet, in which the mass
splittings between neutral and charged components are responsible for the
$W$-boson mass newly measured by the CDF collaboration. This model can not only
generate non-vanishing Majorana neutrino masses via the interaction of
right-handed neutrinos and scotogenic scalars, but also explain the Universe's
missing matter in the form of FIMP dark matter. We also study the influence of
the mass splitting on the first order electroweak phase transition, and find
that it can further enhance the transition strength and thus induce
gravitational waves during the phase transition, which may be detected in the
forthcoming detectors such as U-DECIGO.
|
[
{
"created": "Mon, 11 Apr 2022 02:40:16 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Apr 2022 02:32:30 GMT",
"version": "v2"
},
{
"created": "Thu, 23 Jun 2022 15:41:00 GMT",
"version": "v3"
}
] |
2022-08-02
|
[
[
"Liu",
"Xuewen",
""
],
[
"Guo",
"Shu-Yuan",
""
],
[
"Zhu",
"Bin",
""
],
[
"Li",
"Ying",
""
]
] |
We study a minimal extension of the Standard Model by introducing three right-handed neutrinos and a new scotogenic scalar doublet, in which the mass splittings between neutral and charged components are responsible for the $W$-boson mass newly measured by the CDF collaboration. This model can not only generate non-vanishing Majorana neutrino masses via the interaction of right-handed neutrinos and scotogenic scalars, but also explain the Universe's missing matter in the form of FIMP dark matter. We also study the influence of the mass splitting on the first order electroweak phase transition, and find that it can further enhance the transition strength and thus induce gravitational waves during the phase transition, which may be detected in the forthcoming detectors such as U-DECIGO.
|
0804.0718
|
Wojciech Broniowski
|
Wojciech Broniowski, Enrique Ruiz Arriola, Krzysztof Golec-Biernat
|
Generalized parton distributions of the pion
|
presented by WB at SCADRON 70 ``Scalar Mesons and Related Topics,
Lisbon, 11-16 February 2008, 6 pages
|
AIP Conf.Proc.1030:286-290,2008
|
10.1063/1.2973514
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Generalized Parton Distributions of the pion are evaluated in chiral quark
models with the help of double distributions. As a result the polynomiality
conditions are automatically satisfied. In addition, positivity constraints,
proper normalization and support, sum rules, and soft pion theorems are
fulfilled. We obtain explicit expressions holding at the low-energy quark-model
scale, which exhibit no factorization in the t-dependence. The crucial QCD
evolution of the quark-model distributions is carried out up to experimental or
lattice scales. The obtained results for the Parton Distribution Function and
the Parton Distribution Amplitude describe the available experimental and
lattice data, confirming that the quark-model scale is low, around 320 MeV.
|
[
{
"created": "Fri, 4 Apr 2008 12:42:11 GMT",
"version": "v1"
}
] |
2009-11-13
|
[
[
"Broniowski",
"Wojciech",
""
],
[
"Arriola",
"Enrique Ruiz",
""
],
[
"Golec-Biernat",
"Krzysztof",
""
]
] |
Generalized Parton Distributions of the pion are evaluated in chiral quark models with the help of double distributions. As a result the polynomiality conditions are automatically satisfied. In addition, positivity constraints, proper normalization and support, sum rules, and soft pion theorems are fulfilled. We obtain explicit expressions holding at the low-energy quark-model scale, which exhibit no factorization in the t-dependence. The crucial QCD evolution of the quark-model distributions is carried out up to experimental or lattice scales. The obtained results for the Parton Distribution Function and the Parton Distribution Amplitude describe the available experimental and lattice data, confirming that the quark-model scale is low, around 320 MeV.
|
hep-ph/0311289
|
Teresa Montaruli
|
Teresa Montaruli (Bari University and INFN)
|
Report on the High Energy Phenomena Sessions HE 2, HE 3.2-3.4: Neutrinos
and Muons. Interactions, Particle Physics Aspects, Astro-Particle Physics and
Cosmology
|
24 pages, 10 figures, uses tsukuba.sty. To appear in
Plenary/Highlight/Rapporteur Proceedings of 28th International Cosmic Ray
Conference (ICRC 2003), Tsukuba, Japan, 31 Jul.-7 Aug. 2003
| null | null | null |
hep-ph
| null |
The results presented at the 28th International Cosmic Ray Conference on
neutrino and muon physics are summarized. Neutrinos and muons provide a huge
amount of information on particle interactions up to very high energies and on
fundamental particle properties. Results on neutrino oscillations in the
atmospheric and solar neutrino sectors are summarized. Oscillations are well
established in both sectors, and a more precise determination of oscillation
parameters is requested in the next future. Neutrino telescopes taking data and
under construction presented numerous results. Neutrinos as probes of the
Universe are hopefully going to open, together with gravitational waves, a new
era for Astrophysics. Cosmology has entered the precision era and the Dark
Matter quest is still an open problem. Direct and indirect searches are
complementary approaches to the problem. The results presented at this
conference confirm that Astroparticle Physics and, in particular, Neutrino
Physics are leading fields in fundamental research.
|
[
{
"created": "Sat, 22 Nov 2003 11:38:18 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Montaruli",
"Teresa",
"",
"Bari University and INFN"
]
] |
The results presented at the 28th International Cosmic Ray Conference on neutrino and muon physics are summarized. Neutrinos and muons provide a huge amount of information on particle interactions up to very high energies and on fundamental particle properties. Results on neutrino oscillations in the atmospheric and solar neutrino sectors are summarized. Oscillations are well established in both sectors, and a more precise determination of oscillation parameters is requested in the next future. Neutrino telescopes taking data and under construction presented numerous results. Neutrinos as probes of the Universe are hopefully going to open, together with gravitational waves, a new era for Astrophysics. Cosmology has entered the precision era and the Dark Matter quest is still an open problem. Direct and indirect searches are complementary approaches to the problem. The results presented at this conference confirm that Astroparticle Physics and, in particular, Neutrino Physics are leading fields in fundamental research.
|
1507.03547
|
Andrei Kataev
|
A.L. Kataev (INR RAS, Moscow) and V.S. Molokoedov (MIPT, Dolgoprudnyi)
|
Fourth-order QCD renormalization group quantities in the {\rm{V}}-scheme
and the relation of the $\beta$-function to the Gell-Mann--Low function in
QED
|
The text is in accordance with the one, published in Phys.Rev.D92
(2015), 5, 054008; title a bit modified, 1 reference removed in accordance
with new style of references presntation in PRD, Editorial misprints in
Eq.(4.17) and above Eq.(5.6) are corrected
| null |
10.1103/PhysRevD.92.054008
|
Extended version of INR-TH-2015-003
|
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The semi-analytical $O(\alpha_s^4)$ expression for the renormalization group
$\beta$-function in the ${\rm{V}}$-scheme is obtained in the case of the
$SU(N_c)$ gauge group. In the process of calculations we use the existing
information about the three-loop perturbative approximation for the QCD static
potential, evaluated in the $\rm{\overline{MS}}$-scheme. The comparison of the
numerical values of the third and fourth coefficients for the QCD RG $\beta$-
functions in the gauge-independent ${\rm{V}}$- and $\rm{\overline{MS}}$-schemes
and in minimal MOM scheme in the the Landau gauge is presented. The
phenomenologically-oriented comparisons for the coefficients of $O(\alpha_s^4)$
expression for the $e^+e^-$-annihilation R-ratio in these schemes are
presented. It is shown, that taking into account of these QCD contributions are
of vital importance and lead to the drastic decrease of the scheme-dependence
ambiguities of the fourth-order perturbative QCD approximations for the
$e^+e^-$ annihilation R-ratio for the number of active flavours,$n_f=5$ in
particular. We demonstrate that in the case of QED with $N$-types of leptons
the coefficients of the $\beta^{\rm{V}}$-function are closely related to the
ones of the Gell-Mann--Low $\Psi$-function and emphasise that they start to
differ from each other at the fourth order due to the appearance of the extra
$N^2$-contribution in the V-scheme. The source of this extra correction is
clarified. The general all-order QED relations between the coefficients of the
$\beta^{\rm{V}}$- and $\Psi$-functions are discussed.
|
[
{
"created": "Mon, 13 Jul 2015 18:49:54 GMT",
"version": "v1"
},
{
"created": "Sat, 8 Aug 2015 17:01:25 GMT",
"version": "v2"
},
{
"created": "Sat, 10 Oct 2015 14:08:07 GMT",
"version": "v3"
}
] |
2015-10-13
|
[
[
"Kataev",
"A. L.",
"",
"INR RAS, Moscow"
],
[
"Molokoedov",
"V. S.",
"",
"MIPT, Dolgoprudnyi"
]
] |
The semi-analytical $O(\alpha_s^4)$ expression for the renormalization group $\beta$-function in the ${\rm{V}}$-scheme is obtained in the case of the $SU(N_c)$ gauge group. In the process of calculations we use the existing information about the three-loop perturbative approximation for the QCD static potential, evaluated in the $\rm{\overline{MS}}$-scheme. The comparison of the numerical values of the third and fourth coefficients for the QCD RG $\beta$- functions in the gauge-independent ${\rm{V}}$- and $\rm{\overline{MS}}$-schemes and in minimal MOM scheme in the the Landau gauge is presented. The phenomenologically-oriented comparisons for the coefficients of $O(\alpha_s^4)$ expression for the $e^+e^-$-annihilation R-ratio in these schemes are presented. It is shown, that taking into account of these QCD contributions are of vital importance and lead to the drastic decrease of the scheme-dependence ambiguities of the fourth-order perturbative QCD approximations for the $e^+e^-$ annihilation R-ratio for the number of active flavours,$n_f=5$ in particular. We demonstrate that in the case of QED with $N$-types of leptons the coefficients of the $\beta^{\rm{V}}$-function are closely related to the ones of the Gell-Mann--Low $\Psi$-function and emphasise that they start to differ from each other at the fourth order due to the appearance of the extra $N^2$-contribution in the V-scheme. The source of this extra correction is clarified. The general all-order QED relations between the coefficients of the $\beta^{\rm{V}}$- and $\Psi$-functions are discussed.
|
hep-ph/0001238
|
Martin Lemoine
|
Martin Lemoine (DARC, CNRS, Obs. Paris-Meudon, France)
|
Moduli constraints on primordial black holes
|
8 pages
|
Phys.Lett. B481 (2000) 333-338
|
10.1016/S0370-2693(00)00469-X
| null |
hep-ph astro-ph
| null |
The amount of late decaying massive particles (e.g., gravitinos, moduli)
produced in the evaporation of primordial black holes (PBHs) of mass
$\Mbh\la10^9 $g is calculated. Limits imposed by big-bang nucleosynthesis on
the abundance of these particles are used to constrain the initial PBH mass
fraction $\beta$ (ratio of PBH energy density to critical energy density at
formation), as: $\beta\la 5\times10^{-19} (\xp/6 10^{-3})^{-1} (\Mbh/10^9 {\rm
g})^{-1/2} (\bar{\Yp}/10^{-14})$; $\xp$ is the fraction of PBH luminosity going
into gravitinos or moduli, $\bar{\Yp}$ is the upper bound imposed by
nucleosynthesis on the number density to entropy density ratio of gravitinos or
moduli. This notably implies that such PBHs should never come to dominate the
cosmic energy density.
|
[
{
"created": "Mon, 24 Jan 2000 14:17:33 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Lemoine",
"Martin",
"",
"DARC, CNRS, Obs. Paris-Meudon, France"
]
] |
The amount of late decaying massive particles (e.g., gravitinos, moduli) produced in the evaporation of primordial black holes (PBHs) of mass $\Mbh\la10^9 $g is calculated. Limits imposed by big-bang nucleosynthesis on the abundance of these particles are used to constrain the initial PBH mass fraction $\beta$ (ratio of PBH energy density to critical energy density at formation), as: $\beta\la 5\times10^{-19} (\xp/6 10^{-3})^{-1} (\Mbh/10^9 {\rm g})^{-1/2} (\bar{\Yp}/10^{-14})$; $\xp$ is the fraction of PBH luminosity going into gravitinos or moduli, $\bar{\Yp}$ is the upper bound imposed by nucleosynthesis on the number density to entropy density ratio of gravitinos or moduli. This notably implies that such PBHs should never come to dominate the cosmic energy density.
|
hep-ph/0512189
|
Philip Schuster
|
Philip C. Schuster, Natalia Toro
|
Persistent Fine-Tuning in Supersymmetry and the NMSSM
|
10 pages, 6 figures, 2 tables
| null | null |
HUTP-05/A0052
|
hep-ph
| null |
We examine the use of modified Higgs sectors to address the little hierarchy
problem of supersymmetry. Such models reduce weak-scale fine-tuning by allowing
lighter stops, but they retain some fine-tuning independent of the Higgs. The
modified Higgs sector can also introduce model-dependent tunings. We consider
the model-independent constraints on naturalness from squark, gluino, chargino
and neutralino searches, as well as the model-dependent tuning in the PQ- and
R-symmetric limits of the NMSSM, where cascade decays or additional quartic
interactions can hide a Higgs without relying on heavy stops. Obtaining viable
electroweak symmetry breaking requires a tuning of $\sim 1-10%$ in the PQ
limit. A large A-term is also necessary to make charginos sufficiently heavy,
and this introduces an additional weak-scale tuning of $\sim 10%$. The
R-symmetric limit requires large marginal couplings, a large singlet soft mass,
and a tuning of $\sim 5-10%$ to break electroweak symmetry. Hiding MSSM-like
Higgs states below $\approx 112$ GeV requires additional tunings of A-terms at
the $\sim 1-10%$ level. Thus, although the NMSSM has rich discovery potential,
it suffers from a unique fine-tuning problem of its own.
|
[
{
"created": "Thu, 15 Dec 2005 20:22:52 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Schuster",
"Philip C.",
""
],
[
"Toro",
"Natalia",
""
]
] |
We examine the use of modified Higgs sectors to address the little hierarchy problem of supersymmetry. Such models reduce weak-scale fine-tuning by allowing lighter stops, but they retain some fine-tuning independent of the Higgs. The modified Higgs sector can also introduce model-dependent tunings. We consider the model-independent constraints on naturalness from squark, gluino, chargino and neutralino searches, as well as the model-dependent tuning in the PQ- and R-symmetric limits of the NMSSM, where cascade decays or additional quartic interactions can hide a Higgs without relying on heavy stops. Obtaining viable electroweak symmetry breaking requires a tuning of $\sim 1-10%$ in the PQ limit. A large A-term is also necessary to make charginos sufficiently heavy, and this introduces an additional weak-scale tuning of $\sim 10%$. The R-symmetric limit requires large marginal couplings, a large singlet soft mass, and a tuning of $\sim 5-10%$ to break electroweak symmetry. Hiding MSSM-like Higgs states below $\approx 112$ GeV requires additional tunings of A-terms at the $\sim 1-10%$ level. Thus, although the NMSSM has rich discovery potential, it suffers from a unique fine-tuning problem of its own.
|
0807.2391
|
Kyrill Bugaev
|
K. A. Bugaev, V. K. Petrov and G. M. Zinovjev
|
Quark Gluon Bags as Reggeons
|
One section removed, a few references added, the Regge trajectories
of free QGP bags are considered
|
Phys.Rev.C79:054913,2009
|
10.1103/PhysRevC.79.054913
| null |
hep-ph
|
http://creativecommons.org/licenses/by-nc-sa/3.0/
|
The influence of the medium dependent finite width of QGP bags on their
equation of state is analyzed within an exactly solvable model. It is argued
that the large width of the QGP bags not only explains the observed deficit in
the number of hadronic resonances, but also clarifies the reason why the heavy
QGP bags cannot be directly observed as metastable states in a hadronic phase.
The model allows us to estimate the minimal value of the width of QGP bags from
a variety of the lattice QCD data and get that the minimal resonance width at
zero temperature is about 600 MeV, whereas the minimal resonance width at the
Hagedorn temperature is about 2000 MeV. As shown these estimates are almost
insensitive to the number of the elementary degrees of freedom. The recent
lattice QCD data are analyzed and it is found that besides sigma T**4 term the
lattice QCD pressure contains T-linear and T**4 ln T terms in the range of
temperatures between 240 MeV and 420 MeV. The presence of the last term in the
pressure bears almost no effect on the width estimates. Our analysis shows that
at hight temperatures the average mass and width of the QGP bags behave in
accordance with the upper bound of the Regge trajectory asymptotics (the linear
asymptotics), whereas at low temperatures they obey the lower bound of the
Regge trajectory asymptotics (the square root one). Since the model explicitly
contains the Hagedorn mass spectrum, it allows us to remove an existing
contradiction between the finite number of hadronic Regge families and the
Hagedorn idea of the exponentially growing mass spectrum of hadronic bags.
|
[
{
"created": "Tue, 15 Jul 2008 15:10:23 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Jun 2009 14:59:03 GMT",
"version": "v2"
}
] |
2009-06-30
|
[
[
"Bugaev",
"K. A.",
""
],
[
"Petrov",
"V. K.",
""
],
[
"Zinovjev",
"G. M.",
""
]
] |
The influence of the medium dependent finite width of QGP bags on their equation of state is analyzed within an exactly solvable model. It is argued that the large width of the QGP bags not only explains the observed deficit in the number of hadronic resonances, but also clarifies the reason why the heavy QGP bags cannot be directly observed as metastable states in a hadronic phase. The model allows us to estimate the minimal value of the width of QGP bags from a variety of the lattice QCD data and get that the minimal resonance width at zero temperature is about 600 MeV, whereas the minimal resonance width at the Hagedorn temperature is about 2000 MeV. As shown these estimates are almost insensitive to the number of the elementary degrees of freedom. The recent lattice QCD data are analyzed and it is found that besides sigma T**4 term the lattice QCD pressure contains T-linear and T**4 ln T terms in the range of temperatures between 240 MeV and 420 MeV. The presence of the last term in the pressure bears almost no effect on the width estimates. Our analysis shows that at hight temperatures the average mass and width of the QGP bags behave in accordance with the upper bound of the Regge trajectory asymptotics (the linear asymptotics), whereas at low temperatures they obey the lower bound of the Regge trajectory asymptotics (the square root one). Since the model explicitly contains the Hagedorn mass spectrum, it allows us to remove an existing contradiction between the finite number of hadronic Regge families and the Hagedorn idea of the exponentially growing mass spectrum of hadronic bags.
|
hep-ph/0003113
|
Vladimir Anisovich
|
A.V. Anisovich, V.V. Anisovich, and A.V. Sarantsev
|
Systematics of q anti-q states in the (n,M^2) and (J,M^2) planes
|
6 pages, LaTeX, 16 EPS figures, epsfig.sty
|
Phys.Rev.D62:051502,2000
|
10.1103/PhysRevD.62.051502
| null |
hep-ph
| null |
In the mass region up to M < 2400 MeV we systematise mesons on the plots
(n,M^2) and (J,M^2), thus setting their classification in terms of n^{2S+1}L_J
q anti-q states. The trajectories on the (n,M^2)-plots are drawn for the
following (IJ^{PC})-states: a_0(10^{++}), a_1(11^{++}), a_2(12^{++}),
a_3(13^{++}), a_4(14^{++}), pi(10^{-+}), pi_2(12^{-+}), eta(00^{-+}),
eta_2(02^{-+})$, rho(11^{--}), f_0(00^{++}), f_2(02^{++}). All trajectories are
linear, with nearly the same slopes. At the (J,M^2)-plot we set out meson
states for leading and daughter trajectories: for pi, rho, a_1, a_2 and P'.
|
[
{
"created": "Mon, 13 Mar 2000 10:45:36 GMT",
"version": "v1"
}
] |
2009-12-30
|
[
[
"Anisovich",
"A. V.",
""
],
[
"Anisovich",
"V. V.",
""
],
[
"Sarantsev",
"A. V.",
""
]
] |
In the mass region up to M < 2400 MeV we systematise mesons on the plots (n,M^2) and (J,M^2), thus setting their classification in terms of n^{2S+1}L_J q anti-q states. The trajectories on the (n,M^2)-plots are drawn for the following (IJ^{PC})-states: a_0(10^{++}), a_1(11^{++}), a_2(12^{++}), a_3(13^{++}), a_4(14^{++}), pi(10^{-+}), pi_2(12^{-+}), eta(00^{-+}), eta_2(02^{-+})$, rho(11^{--}), f_0(00^{++}), f_2(02^{++}). All trajectories are linear, with nearly the same slopes. At the (J,M^2)-plot we set out meson states for leading and daughter trajectories: for pi, rho, a_1, a_2 and P'.
|
2303.06752
|
Kai Zhou
|
Wan-Bing He, Yu-Gang Ma, Long-Gang Pang, Huichao Song, Kai Zhou
|
High energy nuclear physics meets Machine Learning
|
30 pages, 20 figures, mini-review
| null | null | null |
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Though being seemingly disparate and with relatively new intersection, high
energy nuclear physics and machine learning have already begun to merge and
yield interesting results during the last few years. It's worthy to raise the
profile of utilizing this novel mindset from machine learning in high energy
nuclear physics, to help more interested readers see the breadth of activities
around this intersection. The aim of this mini-review is to introduce to the
community the current status and report an overview of applying machine
learning for high energy nuclear physics, to present from different aspects and
examples how scientific questions involved in high energy nuclear physics can
be tackled using machine learning.
|
[
{
"created": "Sun, 12 Mar 2023 21:00:53 GMT",
"version": "v1"
}
] |
2023-03-14
|
[
[
"He",
"Wan-Bing",
""
],
[
"Ma",
"Yu-Gang",
""
],
[
"Pang",
"Long-Gang",
""
],
[
"Song",
"Huichao",
""
],
[
"Zhou",
"Kai",
""
]
] |
Though being seemingly disparate and with relatively new intersection, high energy nuclear physics and machine learning have already begun to merge and yield interesting results during the last few years. It's worthy to raise the profile of utilizing this novel mindset from machine learning in high energy nuclear physics, to help more interested readers see the breadth of activities around this intersection. The aim of this mini-review is to introduce to the community the current status and report an overview of applying machine learning for high energy nuclear physics, to present from different aspects and examples how scientific questions involved in high energy nuclear physics can be tackled using machine learning.
|
1706.09907
|
Sezen Sekmen
|
Pushpalatha C. Bhat, Harrison B. Prosper, Sezen Sekmen, Chip Stewart
|
Optimizing Event Selection with the Random Grid Search
|
26 pages, 9 figures
|
Published in Comput.Phys.Commun. 228 (2018) 245-257
|
10.1016/j.cpc.2018.02.018
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The random grid search (RGS) is a simple, but efficient, stochastic algorithm
to find optimal cuts that was developed in the context of the search for the
top quark at Fermilab in the mid-1990s. The algorithm, and associated code,
have been enhanced recently with the introduction of two new cut types, one of
which has been successfully used in searches for supersymmetry at the Large
Hadron Collider. The RGS optimization algorithm is described along with the
recent developments, which are illustrated with two examples from particle
physics. One explores the optimization of the selection of vector boson fusion
events in the four-lepton decay mode of the Higgs boson and the other optimizes
SUSY searches using boosted objects and the razor variables.
|
[
{
"created": "Thu, 29 Jun 2017 18:00:28 GMT",
"version": "v1"
},
{
"created": "Thu, 10 May 2018 18:14:28 GMT",
"version": "v2"
}
] |
2018-05-14
|
[
[
"Bhat",
"Pushpalatha C.",
""
],
[
"Prosper",
"Harrison B.",
""
],
[
"Sekmen",
"Sezen",
""
],
[
"Stewart",
"Chip",
""
]
] |
The random grid search (RGS) is a simple, but efficient, stochastic algorithm to find optimal cuts that was developed in the context of the search for the top quark at Fermilab in the mid-1990s. The algorithm, and associated code, have been enhanced recently with the introduction of two new cut types, one of which has been successfully used in searches for supersymmetry at the Large Hadron Collider. The RGS optimization algorithm is described along with the recent developments, which are illustrated with two examples from particle physics. One explores the optimization of the selection of vector boson fusion events in the four-lepton decay mode of the Higgs boson and the other optimizes SUSY searches using boosted objects and the razor variables.
|
hep-ph/9912399
|
Bryan Webber
|
B.R. Webber
|
Theoretical Aspects of Particle Production
|
26 pages, 27 figures. Lectures at International Summer School on
Particle Production Spanning MeV and TeV Energies, Nijmegen, The Netherlands,
August 1999
| null | null |
CERN-TH/99-408, Cavendish-HEP-99/18
|
hep-ph
| null |
These lectures describe some of the latest data on particle production in
high-energy collisions and compare them with theoretical calculations and
models based on QCD. The main topics covered are: fragmentation functions and
factorization, small-x fragmentation, hadronization models, differences between
quark and gluon fragmentation, current and target fragmentation in deep
inelastic scattering, and heavy quark fragmentation.
|
[
{
"created": "Fri, 17 Dec 1999 13:51:15 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Webber",
"B. R.",
""
]
] |
These lectures describe some of the latest data on particle production in high-energy collisions and compare them with theoretical calculations and models based on QCD. The main topics covered are: fragmentation functions and factorization, small-x fragmentation, hadronization models, differences between quark and gluon fragmentation, current and target fragmentation in deep inelastic scattering, and heavy quark fragmentation.
|
1601.03575
|
HongWei Ke
|
Hong-Wei Ke and Xue-Qian Li
|
Study on decays of $Z_c(4020)$ and $Z_c(3900)$ into $h_c+\pi$
|
15 pages, 4 figures, will be published in EPJC
|
Eur.Phys.J. C76 (2016) no.6, 334
|
10.1140/epjc/s10052-016-4183-9
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
At the invariant mass spectrum of $h_c\pi^\pm$ a new resonance $Z_c(4020)$
has been observed, however the previously confirmed $Z_c(3900)$ does not show
up at this channel. In this paper we assume that $Z_c(3900)$ and $Z_c(4020)$
are molecular states of $D\bar D^*(D^{*} \bar D)$ and $D^*\bar D^*$
respectively, then we calculate the transition rates of $Z_c(3900)\to h_c+\pi$
and $Z_c(4020)\to h_c+\pi$ in the light front model. Our results show that the
partial width of $Z_c(3900)\to h_c+\pi$ is only three times smaller than that
of $Z_c(4020)\to h_c+\pi$. $Z_c(4020)$ seems to be a molecular state, so if
$Z_c(3900)$ is also a molecular state it should be observed in the portal
$e^+e^-\to h_c\pi^\pm$ as long as the database is sufficiently large, by
contrary if the future more precise measurements still cannot find $Z_c(3900)$
at $h_c\pi^\pm$ channel, the molecular assignment to $Z_c(3900)$ should be
ruled out.
|
[
{
"created": "Thu, 14 Jan 2016 12:14:42 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Jun 2016 10:31:30 GMT",
"version": "v2"
}
] |
2017-09-08
|
[
[
"Ke",
"Hong-Wei",
""
],
[
"Li",
"Xue-Qian",
""
]
] |
At the invariant mass spectrum of $h_c\pi^\pm$ a new resonance $Z_c(4020)$ has been observed, however the previously confirmed $Z_c(3900)$ does not show up at this channel. In this paper we assume that $Z_c(3900)$ and $Z_c(4020)$ are molecular states of $D\bar D^*(D^{*} \bar D)$ and $D^*\bar D^*$ respectively, then we calculate the transition rates of $Z_c(3900)\to h_c+\pi$ and $Z_c(4020)\to h_c+\pi$ in the light front model. Our results show that the partial width of $Z_c(3900)\to h_c+\pi$ is only three times smaller than that of $Z_c(4020)\to h_c+\pi$. $Z_c(4020)$ seems to be a molecular state, so if $Z_c(3900)$ is also a molecular state it should be observed in the portal $e^+e^-\to h_c\pi^\pm$ as long as the database is sufficiently large, by contrary if the future more precise measurements still cannot find $Z_c(3900)$ at $h_c\pi^\pm$ channel, the molecular assignment to $Z_c(3900)$ should be ruled out.
|
1501.02962
|
Melahat Bayar
|
M. Bayar, Xiu-Lei Ren, E. Oset
|
States of $\rho D^* \bar D^*$ with $J=3$ within the Fixed Center
Approximation to the Faddeev equations
|
12 pages, 5 figures
| null | null | null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the interaction of the a $\rho$ and $D^*$, $\bar D^*$ with spins
aligned using the Fixed Center Approximation to the Faddeev equations. We
select a cluster of $D^* \bar D^*$, which is found to be bound in $I=0$ and can
be associated to the X(3915), and let the $\rho$ meson orbit around the $D^*$
and $\bar D^*$. In this case we find an $I=1$ state with mass around 4340 MeV
and narrow width of about 50 MeV. We also investigate the case with a cluster
of $\rho D^*$ and let the $\bar D^*$ orbit around the system of the two states.
The $\rho D^*$ cluster is also found to bind and leads to the $D^*_2(2460)$
state. The addition of the extra $\bar D^*$ produces further binding and we
find, with admitted uncertainties, a state of $I=0$ around 4000 MeV, and a less
bound narrow state with $I=1$ around 4200 MeV.
|
[
{
"created": "Tue, 13 Jan 2015 11:27:24 GMT",
"version": "v1"
}
] |
2015-01-14
|
[
[
"Bayar",
"M.",
""
],
[
"Ren",
"Xiu-Lei",
""
],
[
"Oset",
"E.",
""
]
] |
We study the interaction of the a $\rho$ and $D^*$, $\bar D^*$ with spins aligned using the Fixed Center Approximation to the Faddeev equations. We select a cluster of $D^* \bar D^*$, which is found to be bound in $I=0$ and can be associated to the X(3915), and let the $\rho$ meson orbit around the $D^*$ and $\bar D^*$. In this case we find an $I=1$ state with mass around 4340 MeV and narrow width of about 50 MeV. We also investigate the case with a cluster of $\rho D^*$ and let the $\bar D^*$ orbit around the system of the two states. The $\rho D^*$ cluster is also found to bind and leads to the $D^*_2(2460)$ state. The addition of the extra $\bar D^*$ produces further binding and we find, with admitted uncertainties, a state of $I=0$ around 4000 MeV, and a less bound narrow state with $I=1$ around 4200 MeV.
|
0902.0059
|
Mojtaba Mohammadi Najafabadi
|
Mojtaba Mohammadi Najafabadi
|
Heavy Charged Gauge Bosons with General CP Violating Couplings
| null |
Commun.Theor.Phys.53:1137-1139,2010
|
10.1088/0253-6102/53/6/29
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Heavy gauge bosons such as $W^{\prime}$ are expected to exist in many
extensions of the Standard Model. In this paper, it is shown that the most
general Lagrangian for the interaction of $W^{\prime}$ with top and bottom
quarks which consists of V-A and V+A structure with in general complex
couplings produces an Electric Dipole Moment (EDM) for the top quark at one
loop level. We predict the allowed ranges for the mass and couplings of
$W^{\prime}$ by using the upper limit on the top quark EDM.
|
[
{
"created": "Sat, 31 Jan 2009 12:09:20 GMT",
"version": "v1"
},
{
"created": "Tue, 12 May 2009 17:01:36 GMT",
"version": "v2"
}
] |
2014-11-18
|
[
[
"Najafabadi",
"Mojtaba Mohammadi",
""
]
] |
Heavy gauge bosons such as $W^{\prime}$ are expected to exist in many extensions of the Standard Model. In this paper, it is shown that the most general Lagrangian for the interaction of $W^{\prime}$ with top and bottom quarks which consists of V-A and V+A structure with in general complex couplings produces an Electric Dipole Moment (EDM) for the top quark at one loop level. We predict the allowed ranges for the mass and couplings of $W^{\prime}$ by using the upper limit on the top quark EDM.
|
2009.01038
|
Fabien Buisseret Dr
|
Y. Brihaye, F. Buisseret
|
Gravitating bubbles of gluon plasma above deconfinement temperature
| null |
Symmetry 2020, 12(10), 1668 -- Introduction significantly modified
in published version
|
10.3390/sym12101668
| null |
hep-ph gr-qc
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The equation of state of SU(3) Yang-Mills theory can be modelled by an
effective $Z_3-$symmetric potential $V(\vert\phi\vert,\phi^3+\phi^{3*}, T)$
depending on the temperature $T$ and on a scalar field $\phi$ -- the averaged
Polyakov loop. Allowing $\phi$ to be dynamical opens the way to the study of
spatially localized classical configurations of the Polyakov loop. We first
show that spherically symmetric static Q-balls exist in the range
$(1-1.21)\times T_c$, $T_c$ being the deconfinement temperature. Then we argue
that Q-holes solutions, if any are unphysical within our framework. Finally we
couple the Polyakov-loop Lagrangian to Einstein gravity and show that
spherically symmetric static boson stars exist in the same range of
temperature. The Q-ball and boson star solutions we find can be interpreted as
"bubbles" of deconfined gluonic matter; their mean radius is always smaller
than 10 fm.
|
[
{
"created": "Wed, 2 Sep 2020 13:12:46 GMT",
"version": "v1"
}
] |
2020-10-14
|
[
[
"Brihaye",
"Y.",
""
],
[
"Buisseret",
"F.",
""
]
] |
The equation of state of SU(3) Yang-Mills theory can be modelled by an effective $Z_3-$symmetric potential $V(\vert\phi\vert,\phi^3+\phi^{3*}, T)$ depending on the temperature $T$ and on a scalar field $\phi$ -- the averaged Polyakov loop. Allowing $\phi$ to be dynamical opens the way to the study of spatially localized classical configurations of the Polyakov loop. We first show that spherically symmetric static Q-balls exist in the range $(1-1.21)\times T_c$, $T_c$ being the deconfinement temperature. Then we argue that Q-holes solutions, if any are unphysical within our framework. Finally we couple the Polyakov-loop Lagrangian to Einstein gravity and show that spherically symmetric static boson stars exist in the same range of temperature. The Q-ball and boson star solutions we find can be interpreted as "bubbles" of deconfined gluonic matter; their mean radius is always smaller than 10 fm.
|
1207.0587
|
Luca Merlo Dr.
|
Guido Altarelli, Ferruccio Feruglio, Isabella Masina, Luca Merlo
|
Repressing Anarchy in Neutrino Mass Textures
|
v1: 12 pages, 3 figures; v2: 13 pages, 3 figures, text improved,
matches version accepted for publication; v3: submitted to add an
acknowledgment to a network
| null |
10.1007/JHEP11(2012)139
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The recent results that $\theta_{13}$ is relatively large, of the order of
the previous upper bound, and the indications of a sizable deviation of
$\theta_{23}$ from the maximal value are in agreement with the predictions of
Anarchy in the lepton sector. The quark and charged lepton hierarchies can then
be reproduced in a SU(5) GUT context by attributing non-vanishing $U(1)_{FN}$
charges, different for each family, only to the SU(5) tenplet states. The fact
that the observed mass hierarchies are stronger for up quarks than for down
quarks and charged leptons supports this idea. As discussed in the past, in the
flexible context of $SU(5)\otimes U(1)_{FN}$, different patterns of charges can
be adopted going from Anarchy to various types of hierarchy. We revisit this
approach by also considering new models and we compare all versions to the
present data. As a result we confirm that, by relaxing the extreme ansatz of
equal $U(1)_{FN}$ charges for all SU(5) pentaplets and singlets, better
agreement with the data than for Anarchy is obtained without increasing the
model complexity. We also present the distributions obtained in the different
models for the Dirac CP-violating phase. Finally we discuss the relative merits
of these simple models.
|
[
{
"created": "Tue, 3 Jul 2012 07:13:43 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Nov 2012 10:30:03 GMT",
"version": "v2"
},
{
"created": "Wed, 25 Sep 2013 11:57:23 GMT",
"version": "v3"
}
] |
2015-06-05
|
[
[
"Altarelli",
"Guido",
""
],
[
"Feruglio",
"Ferruccio",
""
],
[
"Masina",
"Isabella",
""
],
[
"Merlo",
"Luca",
""
]
] |
The recent results that $\theta_{13}$ is relatively large, of the order of the previous upper bound, and the indications of a sizable deviation of $\theta_{23}$ from the maximal value are in agreement with the predictions of Anarchy in the lepton sector. The quark and charged lepton hierarchies can then be reproduced in a SU(5) GUT context by attributing non-vanishing $U(1)_{FN}$ charges, different for each family, only to the SU(5) tenplet states. The fact that the observed mass hierarchies are stronger for up quarks than for down quarks and charged leptons supports this idea. As discussed in the past, in the flexible context of $SU(5)\otimes U(1)_{FN}$, different patterns of charges can be adopted going from Anarchy to various types of hierarchy. We revisit this approach by also considering new models and we compare all versions to the present data. As a result we confirm that, by relaxing the extreme ansatz of equal $U(1)_{FN}$ charges for all SU(5) pentaplets and singlets, better agreement with the data than for Anarchy is obtained without increasing the model complexity. We also present the distributions obtained in the different models for the Dirac CP-violating phase. Finally we discuss the relative merits of these simple models.
|
0806.4927
|
Bernd Kniehl
|
Bernd A. Kniehl, Anatoly V. Kotikov, Oleg L. Veretin
|
Orthopositronium lifetime: analytic results in O(alpha) and O(alpha^3
ln(alpha))
|
9 pages, 1 figure
|
Phys.Rev.Lett.101:193401,2008
|
10.1103/PhysRevLett.101.193401
|
DESY 08-085
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present the O(alpha) and O(alpha^3 ln(alpha)) corrections to the total
decay width of orthopositronium in closed analytic form, in terms of basic
transcendental numbers, which can be evaluated numerically to arbitrary
precision.
|
[
{
"created": "Mon, 30 Jun 2008 15:33:46 GMT",
"version": "v1"
}
] |
2008-12-18
|
[
[
"Kniehl",
"Bernd A.",
""
],
[
"Kotikov",
"Anatoly V.",
""
],
[
"Veretin",
"Oleg L.",
""
]
] |
We present the O(alpha) and O(alpha^3 ln(alpha)) corrections to the total decay width of orthopositronium in closed analytic form, in terms of basic transcendental numbers, which can be evaluated numerically to arbitrary precision.
|
2108.05306
|
Manuel Pavon Valderrama
|
Mao-Jun Yan, Fang-Zheng Peng, Mario S\'anchez S\'anchez and Manuel
Pavon Valderrama
|
Interpretations of the new LHCb $P_c(4337)^+$ pentaquark state
|
19 pages, 5 tables, 1 figure, corresponds with published version
|
EPJC 82, 574 (2022)
|
10.1140/epjc/s10052-022-10522-7
| null |
hep-ph hep-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Recently the LHCb collaboration has observed a new pentaquark state, the
$P_c(4337)^+$. Owing to its proximity to the $\chi_{c0}(1S) p$, $\bar{D}^*
\Lambda_c$, $\bar{D} \Sigma_c$ and $\bar{D} \Sigma_c^*$ thresholds, this new
pentaquark might very well be a meson-baryon bound state. However its spin and
parity have not been determined yet and none of the previous possibilities can
be ruled out. We briefly explore a few of these options and the consequences
they entail in the present manuscript: (i) the $P_c(4337)^+$ might be a
$\chi_{c0}(1S) p$ bound state, (ii) the $P_c(4312)^+$ and $P_c(4337)^+$ might
be $\bar{D}^* \Lambda_c$ and $\bar{D} \Sigma_c$ states close to threshold,
respectively, where the Breit-Wigner mass might not correspond to the location
of the poles, (iii) the locations of the $P_c(4312)^+$ and $P_c(4337)^+$ might
be explained in terms of the $\bar{D}^* \Lambda_c$-$\bar{D} \Sigma_c$ and
$\bar{D}^* \Lambda_c$-$\bar{D} \Sigma_c^*$ coupled channel dynamics. This last
option, though not the most probable explanation, is still potentially
compatible with the double peak solution of the $P_{cs}(4459)^0$ and with what
we know of the $P_c(4312)^+$. As a byproduct of the previous explorations, we
conjecture the existence of a series of anticharmed meson - antitriplet charmed
baryon bound states and calculate their masses.
|
[
{
"created": "Wed, 11 Aug 2021 16:21:59 GMT",
"version": "v1"
},
{
"created": "Mon, 4 Jul 2022 15:09:13 GMT",
"version": "v2"
}
] |
2022-07-05
|
[
[
"Yan",
"Mao-Jun",
""
],
[
"Peng",
"Fang-Zheng",
""
],
[
"Sánchez",
"Mario Sánchez",
""
],
[
"Valderrama",
"Manuel Pavon",
""
]
] |
Recently the LHCb collaboration has observed a new pentaquark state, the $P_c(4337)^+$. Owing to its proximity to the $\chi_{c0}(1S) p$, $\bar{D}^* \Lambda_c$, $\bar{D} \Sigma_c$ and $\bar{D} \Sigma_c^*$ thresholds, this new pentaquark might very well be a meson-baryon bound state. However its spin and parity have not been determined yet and none of the previous possibilities can be ruled out. We briefly explore a few of these options and the consequences they entail in the present manuscript: (i) the $P_c(4337)^+$ might be a $\chi_{c0}(1S) p$ bound state, (ii) the $P_c(4312)^+$ and $P_c(4337)^+$ might be $\bar{D}^* \Lambda_c$ and $\bar{D} \Sigma_c$ states close to threshold, respectively, where the Breit-Wigner mass might not correspond to the location of the poles, (iii) the locations of the $P_c(4312)^+$ and $P_c(4337)^+$ might be explained in terms of the $\bar{D}^* \Lambda_c$-$\bar{D} \Sigma_c$ and $\bar{D}^* \Lambda_c$-$\bar{D} \Sigma_c^*$ coupled channel dynamics. This last option, though not the most probable explanation, is still potentially compatible with the double peak solution of the $P_{cs}(4459)^0$ and with what we know of the $P_c(4312)^+$. As a byproduct of the previous explorations, we conjecture the existence of a series of anticharmed meson - antitriplet charmed baryon bound states and calculate their masses.
|
hep-ph/0103017
| null |
R. Tomas, H. P\"as, J.W.F. Valle
|
Generalized Bounds on Majoron-neutrino couplings
|
17 pages, LateX, 7 figures, version to be published in Phys. Rev. D
|
Phys.Rev.D64:095005,2001
|
10.1103/PhysRevD.64.095005
| null |
hep-ph
| null |
We discuss limits on neutrino-Majoron couplings both from laboratory
experiments as well as from astrophysics. They apply to the simplest class of
Majoron models which covers a variety of possibilities where neutrinos acquire
mass either via a seesaw-type scheme or via radiative corrections. By adopting
a general framework including CP phases we generalize bounds obtained
previously. The combination of complementary bounds enables us to obtain a
highly non-trivial exclusion region in the parameter space. We find that the
future double beta project GENIUS, together with constraints based on supernova
energy release arguments, could restrict neutrino-Majoron couplings down to the
10^{-7} level.
|
[
{
"created": "Thu, 1 Mar 2001 20:41:22 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Jul 2001 09:23:52 GMT",
"version": "v2"
}
] |
2009-09-17
|
[
[
"Tomas",
"R.",
""
],
[
"Päs",
"H.",
""
],
[
"Valle",
"J. W. F.",
""
]
] |
We discuss limits on neutrino-Majoron couplings both from laboratory experiments as well as from astrophysics. They apply to the simplest class of Majoron models which covers a variety of possibilities where neutrinos acquire mass either via a seesaw-type scheme or via radiative corrections. By adopting a general framework including CP phases we generalize bounds obtained previously. The combination of complementary bounds enables us to obtain a highly non-trivial exclusion region in the parameter space. We find that the future double beta project GENIUS, together with constraints based on supernova energy release arguments, could restrict neutrino-Majoron couplings down to the 10^{-7} level.
|
hep-ph/0101289
|
Aichelin
|
F. Gastineau, R. nebauer and J.Aichelin
|
Thermodynamics of the 3-flavor NJL model : chiral symmetry breaking and
color superconductivity
|
27 pages, 7 figures
|
Phys.Rev. C65 (2002) 045204
|
10.1103/PhysRevC.65.045204
| null |
hep-ph
| null |
Employing an extended three flavor version of the NJL model we discuss in
detail the phase diagram of quark matter. The presence of quark as well as of
diquark condensates gives raise to a rich structure of the phase diagram. We
study in detail the chiral phase transition and the color superconductivity as
well as color flavor locking as a function of the temperature and chemical
potentials of the system.
|
[
{
"created": "Thu, 25 Jan 2001 13:52:26 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jun 2001 12:04:47 GMT",
"version": "v2"
},
{
"created": "Tue, 20 Nov 2001 14:48:33 GMT",
"version": "v3"
}
] |
2009-11-07
|
[
[
"Gastineau",
"F.",
""
],
[
"nebauer",
"R.",
""
],
[
"Aichelin",
"J.",
""
]
] |
Employing an extended three flavor version of the NJL model we discuss in detail the phase diagram of quark matter. The presence of quark as well as of diquark condensates gives raise to a rich structure of the phase diagram. We study in detail the chiral phase transition and the color superconductivity as well as color flavor locking as a function of the temperature and chemical potentials of the system.
|
hep-ph/0502041
|
Konstantin Matchev
|
Marco Battaglia, AseshKrishna Datta, Albert De Roeck, Kyoungchul Kong,
Konstantin T. Matchev
|
Contrasting Supersymmetry and Universal Extra Dimensions at the CLIC
Multi-TeV e+e- Collider
|
20 pages, 13 figures, typeset in JHEP style, uses axodraw. Added new
section 5. Version to appear in JHEP
|
JHEP 0507:033,2005
|
10.1088/1126-6708/2005/07/033
|
UFIFT-HEP-05-05, MCTP-05-42
|
hep-ph hep-ex
| null |
Universal extra dimensions and supersymmetry have rather similar experimental
signatures at hadron colliders. The proper interpretation of an LHC discovery
in either case may therefore require further data from a lepton collider. In
this paper we identify methods for discriminating between the two scenarios at
the linear collider. We study the processes of Kaluza-Klein muon pair
production in universal extra dimensions in parallel to smuon pair production
in supersymmetry, accounting for the effects of detector resolution, beam-beam
interactions and accelerator induced backgrounds. We find that the angular
distributions of the final state muons, the energy spectrum of the radiative
return photon and the total cross-section measurement are powerful
discriminators between the two models. Accurate determination of the particle
masses can be obtained both by a study of the momentum spectrum of the final
state leptons and by a scan of the particle pair production thresholds. We also
calculate the production rates of various Kaluza-Klein particles and discuss
the associated signatures.
|
[
{
"created": "Thu, 3 Feb 2005 22:44:38 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Jul 2005 20:34:18 GMT",
"version": "v2"
}
] |
2009-11-11
|
[
[
"Battaglia",
"Marco",
""
],
[
"Datta",
"AseshKrishna",
""
],
[
"De Roeck",
"Albert",
""
],
[
"Kong",
"Kyoungchul",
""
],
[
"Matchev",
"Konstantin T.",
""
]
] |
Universal extra dimensions and supersymmetry have rather similar experimental signatures at hadron colliders. The proper interpretation of an LHC discovery in either case may therefore require further data from a lepton collider. In this paper we identify methods for discriminating between the two scenarios at the linear collider. We study the processes of Kaluza-Klein muon pair production in universal extra dimensions in parallel to smuon pair production in supersymmetry, accounting for the effects of detector resolution, beam-beam interactions and accelerator induced backgrounds. We find that the angular distributions of the final state muons, the energy spectrum of the radiative return photon and the total cross-section measurement are powerful discriminators between the two models. Accurate determination of the particle masses can be obtained both by a study of the momentum spectrum of the final state leptons and by a scan of the particle pair production thresholds. We also calculate the production rates of various Kaluza-Klein particles and discuss the associated signatures.
|
1405.4314
|
D. Ghilencea
|
I. Antoniadis, E. M. Babalic, D. M. Ghilencea
|
Naturalness in low-scale SUSY models and "non-linear" MSSM
|
20 pages, 7 figures
| null |
10.1140/epjc/s10052-014-3050-9
|
CERN-PH-TH-2014-080
|
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In MSSM models with various boundary conditions for the soft breaking terms
(m_{soft}) and for a higgs mass of 126 GeV, there is a (minimal) electroweak
fine-tuning Delta\approx 800 to 1000 for the constrained MSSM and Delta\approx
500 for non-universal gaugino masses. These values, often regarded as
unacceptably large, may indicate a problem of supersymmetry (SUSY) breaking,
rather than of SUSY itself. A minimal modification of these models is to lower
the SUSY breaking scale in the hidden sector (\sqrt f) to few TeV, which we
show to restore naturalness to more acceptable levels Delta\approx 80 for the
most conservative case of low tan_beta and ultraviolet boundary conditions as
in the constrained MSSM. This is done without introducing additional fields in
the visible sector, unlike other models that attempt to reduce Delta. In the
present case Delta is reduced due to additional (effective) quartic higgs
couplings proportional to the ratio m_{soft}/(\sqrt f) of the visible to the
hidden sector SUSY breaking scales. These couplings are generated by the
auxiliary component of the goldstino superfield. The model is discussed in the
limit its sgoldstino component is integrated out so this superfield is realized
non-linearly (hence the name of the model) while the other MSSM superfields are
in their linear realization. By increasing the hidden sector scale \sqrt f one
obtains a continuous transition for fine-tuning values, from this model to the
usual (gravity mediated) MSSM-like models.
|
[
{
"created": "Fri, 16 May 2014 21:29:04 GMT",
"version": "v1"
}
] |
2015-06-19
|
[
[
"Antoniadis",
"I.",
""
],
[
"Babalic",
"E. M.",
""
],
[
"Ghilencea",
"D. M.",
""
]
] |
In MSSM models with various boundary conditions for the soft breaking terms (m_{soft}) and for a higgs mass of 126 GeV, there is a (minimal) electroweak fine-tuning Delta\approx 800 to 1000 for the constrained MSSM and Delta\approx 500 for non-universal gaugino masses. These values, often regarded as unacceptably large, may indicate a problem of supersymmetry (SUSY) breaking, rather than of SUSY itself. A minimal modification of these models is to lower the SUSY breaking scale in the hidden sector (\sqrt f) to few TeV, which we show to restore naturalness to more acceptable levels Delta\approx 80 for the most conservative case of low tan_beta and ultraviolet boundary conditions as in the constrained MSSM. This is done without introducing additional fields in the visible sector, unlike other models that attempt to reduce Delta. In the present case Delta is reduced due to additional (effective) quartic higgs couplings proportional to the ratio m_{soft}/(\sqrt f) of the visible to the hidden sector SUSY breaking scales. These couplings are generated by the auxiliary component of the goldstino superfield. The model is discussed in the limit its sgoldstino component is integrated out so this superfield is realized non-linearly (hence the name of the model) while the other MSSM superfields are in their linear realization. By increasing the hidden sector scale \sqrt f one obtains a continuous transition for fine-tuning values, from this model to the usual (gravity mediated) MSSM-like models.
|
1609.06320
|
Ken Van Tilburg
|
Asimina Arvanitaki, Savas Dimopoulos, Victor Gorbenko, Junwu Huang,
Ken Van Tilburg
|
A small weak scale from a small cosmological constant
|
58 pages, 16 figures
| null |
10.1007/JHEP05(2017)071
| null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We propose a framework in which Weinberg's anthropic explanation of the
cosmological constant problem also solves the hierarchy problem. The weak scale
is selected by chiral dynamics that controls the stabilization of an extra
dimension. When the Higgs vacuum expectation value is close to a fermion mass
scale, the radius of an extra dimension becomes large, and develops an enhanced
number of vacua available to scan the cosmological constant down to its
observed value. At low energies, the radion necessarily appears as an
unnaturally light scalar, in a range of masses and couplings accessible to
fifth-force searches as well as scalar dark matter searches with atomic clocks
and gravitational-wave detectors. The fermion sector that controls the size of
the extra dimension consists of a pair of electroweak doublets and several
singlets. These leptons satisfy approximate mass relations related to the weak
scale and are accessible to the LHC and future colliders.
|
[
{
"created": "Tue, 20 Sep 2016 20:00:07 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Dec 2017 17:54:27 GMT",
"version": "v2"
}
] |
2017-12-27
|
[
[
"Arvanitaki",
"Asimina",
""
],
[
"Dimopoulos",
"Savas",
""
],
[
"Gorbenko",
"Victor",
""
],
[
"Huang",
"Junwu",
""
],
[
"Van Tilburg",
"Ken",
""
]
] |
We propose a framework in which Weinberg's anthropic explanation of the cosmological constant problem also solves the hierarchy problem. The weak scale is selected by chiral dynamics that controls the stabilization of an extra dimension. When the Higgs vacuum expectation value is close to a fermion mass scale, the radius of an extra dimension becomes large, and develops an enhanced number of vacua available to scan the cosmological constant down to its observed value. At low energies, the radion necessarily appears as an unnaturally light scalar, in a range of masses and couplings accessible to fifth-force searches as well as scalar dark matter searches with atomic clocks and gravitational-wave detectors. The fermion sector that controls the size of the extra dimension consists of a pair of electroweak doublets and several singlets. These leptons satisfy approximate mass relations related to the weak scale and are accessible to the LHC and future colliders.
|
2006.09703
|
Wojciech Broniowski
|
Wojciech Broniowski, Enrique Ruiz Arriola
|
Double parton distributions of the pion
|
6 pages, talk presented by WB at Excited QCD 2020, Krynica Zdr\'oj,
Poland, 2-8 February 2020
| null | null | null |
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present a calculation of valence double parton distributions of the pion
in the framework of chiral quark models. The result obtained at the low-energy
quark model scale is particularly simple, where in the chiral limit a
factorized form follows, $D(x_1,x_2, \vec{q}) = \delta(1-x_1-x_2) F(\vec{q})$
with $x_{1,2}$ standing for the longitudinal momentum fractions of the valence
quark and antiquark, and $\vec{q}$ denotes the relative transverse momentum.
For $\vec{q}=\vec{0}$ the result satisfies the Gaunt-Sterling sum rules. The
QCD evolution to higher scales is carried out within the dDGLAP framework. We
argue that the ratios of the valence Mellin moments $\langle x_1^n x_2^m
\rangle / \langle x_1^n \rangle \langle x_2^m \rangle $, which do not depend on
the dDGLAP evolution, provide particularly convenient measures of the
longitudinal correlations between the partons. Such ratios could be probed in
future lattice QCD simulations.
|
[
{
"created": "Wed, 17 Jun 2020 08:03:00 GMT",
"version": "v1"
}
] |
2020-06-18
|
[
[
"Broniowski",
"Wojciech",
""
],
[
"Arriola",
"Enrique Ruiz",
""
]
] |
We present a calculation of valence double parton distributions of the pion in the framework of chiral quark models. The result obtained at the low-energy quark model scale is particularly simple, where in the chiral limit a factorized form follows, $D(x_1,x_2, \vec{q}) = \delta(1-x_1-x_2) F(\vec{q})$ with $x_{1,2}$ standing for the longitudinal momentum fractions of the valence quark and antiquark, and $\vec{q}$ denotes the relative transverse momentum. For $\vec{q}=\vec{0}$ the result satisfies the Gaunt-Sterling sum rules. The QCD evolution to higher scales is carried out within the dDGLAP framework. We argue that the ratios of the valence Mellin moments $\langle x_1^n x_2^m \rangle / \langle x_1^n \rangle \langle x_2^m \rangle $, which do not depend on the dDGLAP evolution, provide particularly convenient measures of the longitudinal correlations between the partons. Such ratios could be probed in future lattice QCD simulations.
|
1503.06890
|
Pablo Roig
|
A. Guevara, G. L\'opez Castro, P. Roig, S. L. Tostado
|
Long-distance weak annihilation contribution to the $B^{\pm}\to
(\pi^{\pm},K^{\pm}) \ell^+\ell^-$ decays
|
Matching of the long-distance and short-distance descriptions of the
WA contributions added and CP violation results changed accordingly in Table
II. Extended discussion of the (subleading) neglected non-factorizable
corrections to WA at large distances. Title changed, three figures and
several references added, and minor improvements in the text. Version
accepted by PRD
|
Physical Review D 92, 054035 (2015)
|
10.1103/PhysRevD.92.054035
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We propose an alternative evaluation of the long-distance weak annihilation
(WA, also called one-photon exchange in this paper) contribution to the rare
semileptonic $B^{\pm}\to (\pi^{\pm},K^{\pm})\ell^+\ell^-$ ($\ell=e,\,\mu$)
decays. This hadronic description at low energies is matched at intermediate
energies to its short-distance counterpart in terms of quark and gluon degrees
of freedom.
Although the WA contribution does not contribute to solve the possible
breaking of lepton-universality observed by LHCb in the $B^{\pm}\to
K^{\pm}(\mu^+\mu^-/e^+e^-)$ ratio, nor provides an important hadronic
contamination to their decay rates, its contribution to the branching ratios
(and direct CP asymmetry) of the $B^{\pm}\to \pi^{\pm}\ell^+\ell^-$ transitions
turns out to be significant. This hadronic pollution should be taken into
account when looking for new physics effects in decays into pions, which
suggests to restrict these searches to squared lepton-pair invariant mass in
the $(1,8)$ GeV$^2$ range. The interference of the one-photon exchange
contribution with the dominant short-distance one-loop amplitude induces a
sizable CP asymmetry in these rare decays, which calls for dedicated
measurements.
|
[
{
"created": "Tue, 24 Mar 2015 01:47:06 GMT",
"version": "v1"
},
{
"created": "Thu, 26 Mar 2015 18:19:12 GMT",
"version": "v2"
},
{
"created": "Wed, 16 Sep 2015 23:02:54 GMT",
"version": "v3"
}
] |
2015-09-30
|
[
[
"Guevara",
"A.",
""
],
[
"Castro",
"G. López",
""
],
[
"Roig",
"P.",
""
],
[
"Tostado",
"S. L.",
""
]
] |
We propose an alternative evaluation of the long-distance weak annihilation (WA, also called one-photon exchange in this paper) contribution to the rare semileptonic $B^{\pm}\to (\pi^{\pm},K^{\pm})\ell^+\ell^-$ ($\ell=e,\,\mu$) decays. This hadronic description at low energies is matched at intermediate energies to its short-distance counterpart in terms of quark and gluon degrees of freedom. Although the WA contribution does not contribute to solve the possible breaking of lepton-universality observed by LHCb in the $B^{\pm}\to K^{\pm}(\mu^+\mu^-/e^+e^-)$ ratio, nor provides an important hadronic contamination to their decay rates, its contribution to the branching ratios (and direct CP asymmetry) of the $B^{\pm}\to \pi^{\pm}\ell^+\ell^-$ transitions turns out to be significant. This hadronic pollution should be taken into account when looking for new physics effects in decays into pions, which suggests to restrict these searches to squared lepton-pair invariant mass in the $(1,8)$ GeV$^2$ range. The interference of the one-photon exchange contribution with the dominant short-distance one-loop amplitude induces a sizable CP asymmetry in these rare decays, which calls for dedicated measurements.
|
0710.3068
|
Pietro Colangelo
|
P. Colangelo, F. De Fazio, S. Nicotri, M. Rizzi
|
Identifying $D_{sJ}(2700)$ through its decay modes
|
RevTex, 6 pages - references added
|
Phys.Rev.D77:014012,2008
|
10.1103/PhysRevD.77.014012
|
BARI-TH/07-578
|
hep-ph hep-ex
| null |
We study how to assign the recently observed $D_{sJ}(2700)$ meson to an
appropriate level of the $c \bar s$ spectrum by the analysis of its decay modes
in final states comprising a light pseudoscalar meson. We use an effective
lagrangian approach with heavy quark and chiral symmetries, obtaining that the
measurement of the $D^* K$ decay width would allow to distinguish between two
possible assignments.
|
[
{
"created": "Tue, 16 Oct 2007 14:21:44 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Oct 2007 16:12:27 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Colangelo",
"P.",
""
],
[
"De Fazio",
"F.",
""
],
[
"Nicotri",
"S.",
""
],
[
"Rizzi",
"M.",
""
]
] |
We study how to assign the recently observed $D_{sJ}(2700)$ meson to an appropriate level of the $c \bar s$ spectrum by the analysis of its decay modes in final states comprising a light pseudoscalar meson. We use an effective lagrangian approach with heavy quark and chiral symmetries, obtaining that the measurement of the $D^* K$ decay width would allow to distinguish between two possible assignments.
|
1006.1219
|
Roberto Barcelo
|
Roberto Barcelo
|
Higgs bosons in ttbar production
|
Talk given at the 2nd Young Researchers Workshop "Physics Challenges
in the LHC Era", Frascati, May 10 and 13, 2010
|
Proceedings of Second Young Researchers Workshop "Physics
Challenges in the LHC era", Frascati Physics Series LI (2010) 13-18
| null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The top quark has a large Yukawa coupling with the Higgs boson. In the usual
extensions of the standard model the Higgs sector includes extra scalars, which
also tend to couple strongly with the top quark. Unlike the Higgs, these fields
have a natural mass above 2m_t, so they could introduce anomalies in ttbar
production at the LHC. We study their effect on the ttbar invariant mass
distribution at sqrt{s}=7 TeV. We focus on the bosons (H,A) of the minimal SUSY
model and on the scalar field (r) associated to the new scale f in Little Higgs
(LH) models. We show that in all cases the interference with the standard
amplitude dominates over the narrow-width contribution. As a consequence, the
mass difference between H and A or the contribution of an extra T-quark loop in
LH models become important effects in order to determine if these fields are
observable there. We find that a 1 fb^{-1} luminosity could probe the region
tan beta \le 3 of SUSY and v/(sqrt{2}f) \ge 0.3 in LH models.
|
[
{
"created": "Mon, 7 Jun 2010 10:05:32 GMT",
"version": "v1"
},
{
"created": "Fri, 11 Jun 2010 10:54:31 GMT",
"version": "v2"
}
] |
2010-12-10
|
[
[
"Barcelo",
"Roberto",
""
]
] |
The top quark has a large Yukawa coupling with the Higgs boson. In the usual extensions of the standard model the Higgs sector includes extra scalars, which also tend to couple strongly with the top quark. Unlike the Higgs, these fields have a natural mass above 2m_t, so they could introduce anomalies in ttbar production at the LHC. We study their effect on the ttbar invariant mass distribution at sqrt{s}=7 TeV. We focus on the bosons (H,A) of the minimal SUSY model and on the scalar field (r) associated to the new scale f in Little Higgs (LH) models. We show that in all cases the interference with the standard amplitude dominates over the narrow-width contribution. As a consequence, the mass difference between H and A or the contribution of an extra T-quark loop in LH models become important effects in order to determine if these fields are observable there. We find that a 1 fb^{-1} luminosity could probe the region tan beta \le 3 of SUSY and v/(sqrt{2}f) \ge 0.3 in LH models.
|
1704.02104
|
Christoph Herold
|
Jakapat Kannika, Christoph Herold, Ayut Limphirat, Chinorat Kobdaj,
Yupeng Yan
|
Dynamical formation of center domains in quark-gluon plasma
|
6 pages, 4 figures
|
Phys.Rev. C95 (2017) no.3, 034903
|
10.1103/PhysRevC.95.034903
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the formation of domain structures due to spontaneous breakdown of
center symmetry at high temperatures in quenched QCD. We develop a
phenomenological model for the explicit propagation of the Polyakov loop as the
relevant order parameter of the deconfinement phase transition. The surface
tension in the equation of motion is fit in comparison with lattice QCD data.
Results give insight into the dynamical formation of center domains as well as
the formation of energy bands along domain walls and let us estimate the
required time to form such structures above the critical temperature.
|
[
{
"created": "Fri, 7 Apr 2017 06:32:04 GMT",
"version": "v1"
}
] |
2017-04-10
|
[
[
"Kannika",
"Jakapat",
""
],
[
"Herold",
"Christoph",
""
],
[
"Limphirat",
"Ayut",
""
],
[
"Kobdaj",
"Chinorat",
""
],
[
"Yan",
"Yupeng",
""
]
] |
We study the formation of domain structures due to spontaneous breakdown of center symmetry at high temperatures in quenched QCD. We develop a phenomenological model for the explicit propagation of the Polyakov loop as the relevant order parameter of the deconfinement phase transition. The surface tension in the equation of motion is fit in comparison with lattice QCD data. Results give insight into the dynamical formation of center domains as well as the formation of energy bands along domain walls and let us estimate the required time to form such structures above the critical temperature.
|
hep-ph/0204188
|
Giglietto Nicola
|
M. Ambrosio, et al (MACRO Collaborations)
|
Search for cosmic ray sources using muons detected by the MACRO
experiment
|
18 pages, 12 figures
|
Astropart.Phys.18:615-627,2003
|
10.1016/S0927-6505(02)00164-0
| null |
hep-ph
| null |
The MACRO underground detector at Gran Sasso Laboratory recorded 60 million
secondary cosmic ray muons from February 1989 until December 2000. Different
techniques were used to analyze this sample in search for density excesses from
astrophysical point-like sources. No evidence for DC excesses for any source in
an all-sky survey is reported. In addition, searches for muon excess correlated
with the known binary periods of Cygnus X-3 and Hercules X-1, and searches for
statistically significant bursting episodes from known gamma ray sources are
also proved negative.
|
[
{
"created": "Tue, 16 Apr 2002 14:05:34 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Ambrosio",
"M.",
""
]
] |
The MACRO underground detector at Gran Sasso Laboratory recorded 60 million secondary cosmic ray muons from February 1989 until December 2000. Different techniques were used to analyze this sample in search for density excesses from astrophysical point-like sources. No evidence for DC excesses for any source in an all-sky survey is reported. In addition, searches for muon excess correlated with the known binary periods of Cygnus X-3 and Hercules X-1, and searches for statistically significant bursting episodes from known gamma ray sources are also proved negative.
|
1103.4962
|
Alexander Lenz
|
Michal Kreps, Alexander Lenz and Olivier Leroy
|
Summary of WG4: "Lifetime, mixing and weak mixing phase in charm and
beauty, including direct determination of V_{tx}
|
Proceedings of the 6th International Workshop on the CKM Unitarity
Triangle, University of Warwick, United Kingdom, September 6-10, 2010; 14
pages
| null | null |
TUM-HEP-794/11
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present the summary of the Working Group on lifetimes, mixing and weak
mixing phases in charm and beauty mesons at the CKM 2010 workshop. In the past
year or so good progress was achieved on both experimental and theoretical
sides. While this yields improvement in our understanding of neutral meson
mixing, further work is necessary to achieve the highest possible precision in
order to investigate current hints for deviations between experiment and
standard model predictions. With the recent LHC startup we see bright prospects
for the near term future for huge improvements.
|
[
{
"created": "Fri, 25 Mar 2011 13:17:51 GMT",
"version": "v1"
}
] |
2011-03-28
|
[
[
"Kreps",
"Michal",
""
],
[
"Lenz",
"Alexander",
""
],
[
"Leroy",
"Olivier",
""
]
] |
We present the summary of the Working Group on lifetimes, mixing and weak mixing phases in charm and beauty mesons at the CKM 2010 workshop. In the past year or so good progress was achieved on both experimental and theoretical sides. While this yields improvement in our understanding of neutral meson mixing, further work is necessary to achieve the highest possible precision in order to investigate current hints for deviations between experiment and standard model predictions. With the recent LHC startup we see bright prospects for the near term future for huge improvements.
|
hep-ph/9308377
|
Kajia Yuan
|
Kajia Yuan
|
Aspects of Neutralino Dark Matter
|
15pp Latex text + 6 ps figs (included as a uuencoded file, also
available upon request), CTP-TAMU-51/93 and ACT-19/93
| null | null | null |
hep-ph astro-ph
| null |
The possible solution of dark matter problem with neutralinos of
supersymmetric models within the supergravity framework is reviewed. A novel
correlation between the neutralino relic abundance $\Omega_\chi$ and the soft
supersymmetry breaking patterns is demonstrated. It is explained that, this
generic result together with the proton-decay constraint could significantly
reduce the allowed parameter space of the minimal $SU(5)$ supergravity model,
and therefore makes this model more easily testable. The prospect of obtaining
further cosmological constraints from underground experiments for the minimal
$SU(5)$ supergravity model is also briefly discussed.
|
[
{
"created": "Wed, 1 Sep 1993 03:32:17 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Yuan",
"Kajia",
""
]
] |
The possible solution of dark matter problem with neutralinos of supersymmetric models within the supergravity framework is reviewed. A novel correlation between the neutralino relic abundance $\Omega_\chi$ and the soft supersymmetry breaking patterns is demonstrated. It is explained that, this generic result together with the proton-decay constraint could significantly reduce the allowed parameter space of the minimal $SU(5)$ supergravity model, and therefore makes this model more easily testable. The prospect of obtaining further cosmological constraints from underground experiments for the minimal $SU(5)$ supergravity model is also briefly discussed.
|
0707.0351
|
Ivanov Dmitry
|
M. Diehl and D.Yu. Ivanov
|
Dispersion representations for hard exclusive processes
|
24 pages
|
Eur.Phys.J.C52:919-932,2007
|
10.1140/epjc/s10052-007-0401-9
|
DESY 07-094
|
hep-ph
| null |
Several hard exclusive scattering processes admit a description in terms of
generalized parton distributions and perturbative hard-scattering kernels. Both
the physical amplitude and the hard-scattering kernels fulfill dispersion
relations. We give a detailed investigation of their consistency at all orders
in perturbation theory. The results shed light on the information about
generalized parton distributions that can be extracted from the real and
imaginary parts of exclusive amplitudes. They also provide a practical
consistency check for models of these distributions in which Lorentz invariance
is not exactly satisfied.
|
[
{
"created": "Tue, 3 Jul 2007 07:31:53 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Diehl",
"M.",
""
],
[
"Ivanov",
"D. Yu.",
""
]
] |
Several hard exclusive scattering processes admit a description in terms of generalized parton distributions and perturbative hard-scattering kernels. Both the physical amplitude and the hard-scattering kernels fulfill dispersion relations. We give a detailed investigation of their consistency at all orders in perturbation theory. The results shed light on the information about generalized parton distributions that can be extracted from the real and imaginary parts of exclusive amplitudes. They also provide a practical consistency check for models of these distributions in which Lorentz invariance is not exactly satisfied.
|
1511.00670
|
Andrei Neacsu
|
Mihai Horoi and Andrei Neacsu
|
Analysis of mechanisms that could contribute to the neutrinoless
double-beta decay
| null |
Phys. Rev. D 93, 113014 (2016)
|
10.1103/PhysRevD.93.113014
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Neutrinoless double-beta decay, if observed, would signal physics beyond the
Standard Model that could be discovered at energies significantly lower than
those at which the relevant degrees of freedom could be excited. Therefore, it
could be challenging to further use the neutrinoless double-beta decay
observations to distinguish between many beyond Standard Model mechanisms
contributing to this process. Accurate nuclear structure calculations of the
nuclear matrix elements necessary to analyze the decay rates could be helpful
to narrow down the list of contributing mechanisms, and to better identify the
more exotic properties of the neutrinos. We investigate the information one can
get from the angular and energy distribution of the emitted electron assuming
that the right-handed currents exist. For the analysis of these distributions
we calculate the necessary nuclear matrix elements using shell model
techniques.
|
[
{
"created": "Mon, 2 Nov 2015 20:47:53 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Jul 2016 21:04:45 GMT",
"version": "v2"
}
] |
2016-07-13
|
[
[
"Horoi",
"Mihai",
""
],
[
"Neacsu",
"Andrei",
""
]
] |
Neutrinoless double-beta decay, if observed, would signal physics beyond the Standard Model that could be discovered at energies significantly lower than those at which the relevant degrees of freedom could be excited. Therefore, it could be challenging to further use the neutrinoless double-beta decay observations to distinguish between many beyond Standard Model mechanisms contributing to this process. Accurate nuclear structure calculations of the nuclear matrix elements necessary to analyze the decay rates could be helpful to narrow down the list of contributing mechanisms, and to better identify the more exotic properties of the neutrinos. We investigate the information one can get from the angular and energy distribution of the emitted electron assuming that the right-handed currents exist. For the analysis of these distributions we calculate the necessary nuclear matrix elements using shell model techniques.
|
1502.01455
|
Michael G. Kozlov
|
M. G. Kozlov, A. V. Reznichenko
|
Effective vertex of quark production in collision of Reggeized quark and
gluon
|
17 pages, 2 figures; to be published in Physics of Atomic Nuclei
|
Phys. Rev. D 92, 125023 (2015)
|
10.1103/PhysRevD.92.125023
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We calculated the effective vertex of the quark production in the collision
of Reggeized quark and Reggeized gluon in the next-to-leading order (NLO). The
vertex in question is the missing component of the multi-Regge NLO amplitudes
with the quark and gluon exchanges in $t_i$ channels. The calculation allows us
to develop the bootstrap approach to the quark Reggeization proof within
next-to-leading logarithmic approximation.
|
[
{
"created": "Thu, 5 Feb 2015 08:31:13 GMT",
"version": "v1"
}
] |
2015-12-30
|
[
[
"Kozlov",
"M. G.",
""
],
[
"Reznichenko",
"A. V.",
""
]
] |
We calculated the effective vertex of the quark production in the collision of Reggeized quark and Reggeized gluon in the next-to-leading order (NLO). The vertex in question is the missing component of the multi-Regge NLO amplitudes with the quark and gluon exchanges in $t_i$ channels. The calculation allows us to develop the bootstrap approach to the quark Reggeization proof within next-to-leading logarithmic approximation.
|
hep-ph/0606181
|
Silvano Simula
|
D. Guadagnoli, V. Lubicz, M. Papinutto, S. Simula
|
First Lattice QCD Study of the Sigma -> n Axial and Vector Form Factors
with SU(3) Breaking Corrections
|
final version to appear in Nucl. Phys. B
|
Nucl.Phys. B761 (2007) 63-91
|
10.1016/j.nuclphysb.2006.10.022
|
preprint RM3-TH/06-7; TUM-HEP-632/06
|
hep-ph hep-ex hep-lat
| null |
We present the first quenched lattice QCD study of the form factors relevant
for the hyperon semileptonic decay Sigma -> n l nu. The momentum dependence of
both axial and vector form factors is investigated and the values of all the
form factors at zero-momentum transfer are presented. Following the same
strategy already applied to the decay K0 -> pi- l nu, the SU(3)-breaking
corrections to the vector form factor at zero-momentum transfer, f1(0), are
determined with great statistical accuracy in the regime of the simulated quark
masses, which correspond to pion masses above ~ 0.7 GeV. Besides f1(0) also the
axial to vector ratio g1(0) / f1(0), which is relevant for the extraction of
the CKM matrix element Vus, is determined with significant accuracy. Due to the
heavy masses involved, a polynomial extrapolation, which does not include the
effects of meson loops, is performed down to the physical quark masses,
obtaining f1(0) = -0.948 +/- 0.029 and g1(0) / f1(0) = -0.287 +/- 0.052, where
the uncertainties do not include the quenching effect. Adding a recent
next-to-leading order determination of chiral loops, calculated within the
Heavy Baryon Chiral Perturbation Theory in the approximation of neglecting the
decuplet contribution, we obtain f1(0) = -0.988 +/- 0.029(lattice) +/-
0.040(HBChPT). Our findings indicate that SU(3)-breaking corrections are
moderate on both f1(0) and g1(0). They also favor the experimental scenario in
which the weak electricity form factor, g2(0), is large and positive, and
correspondingly the value of |g1(0) / f1(0)| is reduced with respect to the one
obtained with the conventional assumption g2(q**2) = 0 based on exact SU(3)
symmetry.
|
[
{
"created": "Fri, 16 Jun 2006 14:18:09 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Oct 2006 13:27:13 GMT",
"version": "v2"
}
] |
2009-11-11
|
[
[
"Guadagnoli",
"D.",
""
],
[
"Lubicz",
"V.",
""
],
[
"Papinutto",
"M.",
""
],
[
"Simula",
"S.",
""
]
] |
We present the first quenched lattice QCD study of the form factors relevant for the hyperon semileptonic decay Sigma -> n l nu. The momentum dependence of both axial and vector form factors is investigated and the values of all the form factors at zero-momentum transfer are presented. Following the same strategy already applied to the decay K0 -> pi- l nu, the SU(3)-breaking corrections to the vector form factor at zero-momentum transfer, f1(0), are determined with great statistical accuracy in the regime of the simulated quark masses, which correspond to pion masses above ~ 0.7 GeV. Besides f1(0) also the axial to vector ratio g1(0) / f1(0), which is relevant for the extraction of the CKM matrix element Vus, is determined with significant accuracy. Due to the heavy masses involved, a polynomial extrapolation, which does not include the effects of meson loops, is performed down to the physical quark masses, obtaining f1(0) = -0.948 +/- 0.029 and g1(0) / f1(0) = -0.287 +/- 0.052, where the uncertainties do not include the quenching effect. Adding a recent next-to-leading order determination of chiral loops, calculated within the Heavy Baryon Chiral Perturbation Theory in the approximation of neglecting the decuplet contribution, we obtain f1(0) = -0.988 +/- 0.029(lattice) +/- 0.040(HBChPT). Our findings indicate that SU(3)-breaking corrections are moderate on both f1(0) and g1(0). They also favor the experimental scenario in which the weak electricity form factor, g2(0), is large and positive, and correspondingly the value of |g1(0) / f1(0)| is reduced with respect to the one obtained with the conventional assumption g2(q**2) = 0 based on exact SU(3) symmetry.
|
hep-ph/0506257
|
Jens Erler
|
Paul Langacker, Jens Erler, Eduardo Peinado
|
Neutrino Physics
|
Lectures presented by Paul Langacker at the 11th Mexican School of
Particles and Fields, Xalapa, Ver., Mexico, August 2004 (33 pages)
|
J.Phys.Conf.Ser.18:154-187,2005
|
10.1088/1742-6596/18/1/004
|
FT-2005-01
|
hep-ph
| null |
The theoretical and experimental bases of neutrino mass and mixing are
reviewed. A brief chronological evolution of the weak interactions, the
electroweak Standard Model, and neutrinos is presented. Dirac and Majorana mass
terms are explained as well as models such as the seesaw mechanism. Schemes for
two, three and four neutrino mixings are presented.
|
[
{
"created": "Fri, 24 Jun 2005 18:37:54 GMT",
"version": "v1"
}
] |
2009-03-02
|
[
[
"Langacker",
"Paul",
""
],
[
"Erler",
"Jens",
""
],
[
"Peinado",
"Eduardo",
""
]
] |
The theoretical and experimental bases of neutrino mass and mixing are reviewed. A brief chronological evolution of the weak interactions, the electroweak Standard Model, and neutrinos is presented. Dirac and Majorana mass terms are explained as well as models such as the seesaw mechanism. Schemes for two, three and four neutrino mixings are presented.
|
0901.4841
|
Xin-Qiang Li
|
M. Beneke (RWTH Aachen University&CERN), Xin-Qiang Li (RWTH Aachen
University), L. Vernazza (RWTH Aachen University)
|
Hadronic B decays in the MSSM with large tan(beta)
|
16 pages, 2 figures
|
Eur.Phys.J.C61:429-438,2009
|
10.1140/epjc/s10052-009-0989-z
|
PITHA-09-04, CERN-PH-TH/2009-017, SFB/CPP-09-09
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present an analysis of non-leptonic B decays in the minimally
flavour-violating MSSM with large tan(beta). We relate the Wilson coefficients
of the relevant hadronic scalar operators to leptonic observables, showing that
the present limits on the Bs->mu+ mu- and B+->tau nu_tau branching fractions
exclude any visible effect in hadronic decays. We study the transverse helicity
amplitudes of B->VV decays, which exhibit an enhanced sensitivity to the scalar
operators, showing that even though an order one modification relative to the
SM is not excluded in some of these amplitudes, they are too small to be
detected at B factories.
|
[
{
"created": "Fri, 30 Jan 2009 09:08:25 GMT",
"version": "v1"
}
] |
2010-04-15
|
[
[
"Beneke",
"M.",
"",
"RWTH Aachen University&CERN"
],
[
"Li",
"Xin-Qiang",
"",
"RWTH Aachen\n University"
],
[
"Vernazza",
"L.",
"",
"RWTH Aachen University"
]
] |
We present an analysis of non-leptonic B decays in the minimally flavour-violating MSSM with large tan(beta). We relate the Wilson coefficients of the relevant hadronic scalar operators to leptonic observables, showing that the present limits on the Bs->mu+ mu- and B+->tau nu_tau branching fractions exclude any visible effect in hadronic decays. We study the transverse helicity amplitudes of B->VV decays, which exhibit an enhanced sensitivity to the scalar operators, showing that even though an order one modification relative to the SM is not excluded in some of these amplitudes, they are too small to be detected at B factories.
|
1002.5044
|
Michael Atkins
|
Michael Atkins, Stephan J. Huber
|
Suppressing Lepton Flavour Violation in a Soft-Wall Extra Dimension
|
20 pages, 5 figures. Version 2: Final PRD version
|
Phys.Rev.D82:056007,2010
|
10.1103/PhysRevD.82.056007
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A soft-wall warped extra dimension allows one to relax the tight constraints
imposed by electroweak data in conventional Randall-Sundrum models. We
investigate a setup, where the lepton flavour structure of the Standard Model
is realised by split fermion locations. Bulk fermions with general locations
are not analytically tractable in a soft-wall background, so we follow a
numerical approach to perform the Kaluza-Klein reduction. Lepton flavour
violation is induced by the exchange of Kaluza-Klein gauge bosons. We find that
rates for processes such as muon-electron conversion are significantly reduced
compared to hard-wall models, allowing for a Kaluza-Klein scale as low as 2
TeV. Accommodating small neutrino masses forces one to introduce a large
hierarchy of scales into the model, making pressing the question of a suitable
stabilisation mechanism.
|
[
{
"created": "Fri, 26 Feb 2010 19:33:15 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Jan 2011 11:29:46 GMT",
"version": "v2"
}
] |
2011-01-20
|
[
[
"Atkins",
"Michael",
""
],
[
"Huber",
"Stephan J.",
""
]
] |
A soft-wall warped extra dimension allows one to relax the tight constraints imposed by electroweak data in conventional Randall-Sundrum models. We investigate a setup, where the lepton flavour structure of the Standard Model is realised by split fermion locations. Bulk fermions with general locations are not analytically tractable in a soft-wall background, so we follow a numerical approach to perform the Kaluza-Klein reduction. Lepton flavour violation is induced by the exchange of Kaluza-Klein gauge bosons. We find that rates for processes such as muon-electron conversion are significantly reduced compared to hard-wall models, allowing for a Kaluza-Klein scale as low as 2 TeV. Accommodating small neutrino masses forces one to introduce a large hierarchy of scales into the model, making pressing the question of a suitable stabilisation mechanism.
|
1406.7481
|
Xiang Liu
|
Rui Chen, Zhi-Feng Sun, Xiang Liu and S. M. Gerasyuta
|
Predicting exotic molecular states composed of nucleon and P-wave
charmed meson
|
10 pages, 4 tables, 3 figure. Accepted by Phys. Rev. D
|
Phys. Rev. D 90, 034011 (2014)
|
10.1103/PhysRevD.90.034011
| null |
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this work, we study the interaction between a nucleon and a $P$-wave
charmed meson in the $T$ doublet by exchanging a pion. Our calculations
indicate that a nucleon and a $P$-wave charmed meson with $J^P=0^+$ or
$J^P=1^+$ in the $T$ doublet can form bound states. We propose the experimental
search for these exotic molecular states near the $D_1(2420)N$ and
$D_2^*(2460)N$ thresholds, where Belle, LHCb and the forthcoming Belle II have
the discovery potential for them.
|
[
{
"created": "Sun, 29 Jun 2014 09:52:55 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Jul 2014 02:49:02 GMT",
"version": "v2"
},
{
"created": "Thu, 7 Aug 2014 07:24:18 GMT",
"version": "v3"
}
] |
2014-08-27
|
[
[
"Chen",
"Rui",
""
],
[
"Sun",
"Zhi-Feng",
""
],
[
"Liu",
"Xiang",
""
],
[
"Gerasyuta",
"S. M.",
""
]
] |
In this work, we study the interaction between a nucleon and a $P$-wave charmed meson in the $T$ doublet by exchanging a pion. Our calculations indicate that a nucleon and a $P$-wave charmed meson with $J^P=0^+$ or $J^P=1^+$ in the $T$ doublet can form bound states. We propose the experimental search for these exotic molecular states near the $D_1(2420)N$ and $D_2^*(2460)N$ thresholds, where Belle, LHCb and the forthcoming Belle II have the discovery potential for them.
|
hep-ph/0001210
|
Alexander Ya. Parkhomenko
|
N.V. Mikheev, A.Ya. Parkhomenko, and L.A. Vassilevskaya
|
Mass Shift of Axion in Magnetic Field
|
4 pages, latex2e, 2 PS figures, uses ws-p8-50x6-00.sty (included) and
amssymb.sty. Talk at the International Workshop on Particle Physics and the
Early Universe (COSMO-99), Trieste, Italy, 27 September - 3 October 1999
| null |
10.1142/9789812792129_0044
|
YARU-HE-00/02
|
hep-ph
| null |
A mass-shift of the axion propagating in an external constant homogenious
magnetic field is calculated. The contributions via an electron loop and a
virtual photon are examined. It is shown that the virtual photon contribution
dominates substantially over the electron-loop one. Under the conditions of the
early Universe the electron-loop contribution to the massless axion mass-shift
is equal to zero while the virtual photon contribution is finite and can be of
order of the recent restrictions on the axion mass.
|
[
{
"created": "Thu, 20 Jan 2000 11:51:28 GMT",
"version": "v1"
}
] |
2016-11-03
|
[
[
"Mikheev",
"N. V.",
""
],
[
"Parkhomenko",
"A. Ya.",
""
],
[
"Vassilevskaya",
"L. A.",
""
]
] |
A mass-shift of the axion propagating in an external constant homogenious magnetic field is calculated. The contributions via an electron loop and a virtual photon are examined. It is shown that the virtual photon contribution dominates substantially over the electron-loop one. Under the conditions of the early Universe the electron-loop contribution to the massless axion mass-shift is equal to zero while the virtual photon contribution is finite and can be of order of the recent restrictions on the axion mass.
|
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