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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2210.11276
|
Chengdong Han
|
Chengdong Han, Wei Kou, Rong Wang, Xurong Chen
|
Extraction of $\omega$n, $\omega$p and $\phi$N scattering lengths from
$\omega$ and $\phi$ differential photoproduction cross sections on the
deuterium target
|
7 pages, 6 figures
| null |
10.1103/PhysRevC.107.015204
| null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
In this study, we try to extract $\omega n$, $\omega p$ and $\phi$N
scattering lengths from the differential cross-section data of near-threshold
$\omega$ and $\phi$ photoproductions not only to the energy at threshold
t$_{thr}$, but also in t to t = 0. The incoherent data of $\omega$ and $\phi$
photoproductions on deuterium target for scattering length extractions are
provided by CBELSA/TAPS Collaboration and LEPS Collaboration respectively,
where the deuteron is usually approximated as a weakly bound state of a
quasi-free neutron plus a quasi-free proton. Under the Vector Meson Doninance
model and the assumption of energy independence of the differential
cross-section, we obtained the $|\alpha_{\omega n^{*}}|$ and $|\alpha_{\omega
p^{*}}|$ of loosely bound neutron and proton in the deuteron to be 0.709 $\pm$
0.078 fm and 0.621 $\pm$ 0.022 fm respectively at threshold t$_{thr}$ (1.258
$\pm$ 0.130 fm and 1.056 $\pm$ 0.032 fm respectively in t to t = 0) for the
first time by fitting the near-threshold data of $\gamma$d $\rightarrow$
$\omega$n(p) and $\gamma$d $\rightarrow$ $\omega$p(n). For a comparison study,
we also extracted the scattering length $|\alpha_{\omega p}|$ of the free
proton from the $\omega$ photoproduction on the hydrogen target by CBELSA/TAPS
Collaboration. With the near-threshold and incoherent $\phi$ photoproduction
data of $\gamma$d $\rightarrow$ $\phi$pn by LEPS Collaboration, we obtained
scattering length $|\alpha_{\phi N}|$ of the bound nucleon inside the deuteron
to be 0.109 $\pm$ 0.008 fm at threshold t$_{thr}$ and 0.276 $\pm$ 0.010 fm in t
to t = 0, respectively. The obtained $|\alpha_{\omega p}|$ and $|\alpha_{\phi
N}|$ are basically in agreement with the experimental indications and the
theoretical predictions within the current uncertainties.
|
[
{
"created": "Thu, 20 Oct 2022 13:47:24 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Oct 2022 14:31:18 GMT",
"version": "v2"
},
{
"created": "Sat, 29 Oct 2022 10:35:18 GMT",
"version": "v3"
}
] |
2023-02-01
|
[
[
"Han",
"Chengdong",
""
],
[
"Kou",
"Wei",
""
],
[
"Wang",
"Rong",
""
],
[
"Chen",
"Xurong",
""
]
] |
In this study, we try to extract $\omega n$, $\omega p$ and $\phi$N scattering lengths from the differential cross-section data of near-threshold $\omega$ and $\phi$ photoproductions not only to the energy at threshold t$_{thr}$, but also in t to t = 0. The incoherent data of $\omega$ and $\phi$ photoproductions on deuterium target for scattering length extractions are provided by CBELSA/TAPS Collaboration and LEPS Collaboration respectively, where the deuteron is usually approximated as a weakly bound state of a quasi-free neutron plus a quasi-free proton. Under the Vector Meson Doninance model and the assumption of energy independence of the differential cross-section, we obtained the $|\alpha_{\omega n^{*}}|$ and $|\alpha_{\omega p^{*}}|$ of loosely bound neutron and proton in the deuteron to be 0.709 $\pm$ 0.078 fm and 0.621 $\pm$ 0.022 fm respectively at threshold t$_{thr}$ (1.258 $\pm$ 0.130 fm and 1.056 $\pm$ 0.032 fm respectively in t to t = 0) for the first time by fitting the near-threshold data of $\gamma$d $\rightarrow$ $\omega$n(p) and $\gamma$d $\rightarrow$ $\omega$p(n). For a comparison study, we also extracted the scattering length $|\alpha_{\omega p}|$ of the free proton from the $\omega$ photoproduction on the hydrogen target by CBELSA/TAPS Collaboration. With the near-threshold and incoherent $\phi$ photoproduction data of $\gamma$d $\rightarrow$ $\phi$pn by LEPS Collaboration, we obtained scattering length $|\alpha_{\phi N}|$ of the bound nucleon inside the deuteron to be 0.109 $\pm$ 0.008 fm at threshold t$_{thr}$ and 0.276 $\pm$ 0.010 fm in t to t = 0, respectively. The obtained $|\alpha_{\omega p}|$ and $|\alpha_{\phi N}|$ are basically in agreement with the experimental indications and the theoretical predictions within the current uncertainties.
|
hep-ph/0210206
|
Kazumasa Ukai
|
Cai-Dian Lu, Kazumasa Ukai
|
Branching Ratios of $B \to D_s K$ Decays in Perturbative QCD Approach
|
18 pages, 3 figures
|
Eur.Phys.J.C28:305-312,2003
|
10.1140/epjc/s2003-01150-4
| null |
hep-ph
| null |
The rare decays $B^0 \to D_s^- K^+$ and $B^+ \to D_s^+ \bar{K}^0$ can occur
only via annihilation type diagrams in the standard model. We calculate these
decays in perturbative QCD approach. We found that the calculated branching
ratio of $B^0 \to D_s^- K^+$ agreed with the data which had been observed in
the KEK and SLAC $B$ factories. While the decay $B^+ \to D_s^+ \bar{K}^0$ has a
very small branching ratio at ${\cal O}(10^{-8})$, due to the suppression from
CKM matrix elements $|V_{ub}^* V_{cd}|$.
|
[
{
"created": "Tue, 15 Oct 2002 03:05:59 GMT",
"version": "v1"
}
] |
2009-01-07
|
[
[
"Lu",
"Cai-Dian",
""
],
[
"Ukai",
"Kazumasa",
""
]
] |
The rare decays $B^0 \to D_s^- K^+$ and $B^+ \to D_s^+ \bar{K}^0$ can occur only via annihilation type diagrams in the standard model. We calculate these decays in perturbative QCD approach. We found that the calculated branching ratio of $B^0 \to D_s^- K^+$ agreed with the data which had been observed in the KEK and SLAC $B$ factories. While the decay $B^+ \to D_s^+ \bar{K}^0$ has a very small branching ratio at ${\cal O}(10^{-8})$, due to the suppression from CKM matrix elements $|V_{ub}^* V_{cd}|$.
|
0711.4789
|
Alexander Ilyichev
|
I. Akushevich, A. Ilyichev, M. Osipenko
|
Lowest order QED radiative corrections to five-fold differential cross
section of hadron leptoproduction
|
19 pages, 6 figures, 1 table
|
Phys.Lett.B672:35-44,2009
|
10.1016/j.physletb.2008.12.058
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The contribution of exclusive radiative tail to the cross section of
semi-inclusive hadron leptoproduction has been calculated exactly for the first
time. Although the experience of inclusive data analyses suggests us that the
contribution of radiative tail from the elastic peak is of particular
importance, similar effects in the semi-inclusive process were only recently
estimated in the peaking approximation. The explicit expressions for the lepton
part of the lowest order QED contribution of exclusive radiative tail to the
five-fold differential cross section are obtained and discussed. Numerical
estimates, provided within Jefferson Lab kinematic conditions, demonstrate
rather large effects of the exclusive radiative tail in the region at
semi-inclusive threshold and for high energy of detected hadron.
|
[
{
"created": "Thu, 29 Nov 2007 18:04:24 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Jan 2009 12:28:20 GMT",
"version": "v2"
}
] |
2009-01-19
|
[
[
"Akushevich",
"I.",
""
],
[
"Ilyichev",
"A.",
""
],
[
"Osipenko",
"M.",
""
]
] |
The contribution of exclusive radiative tail to the cross section of semi-inclusive hadron leptoproduction has been calculated exactly for the first time. Although the experience of inclusive data analyses suggests us that the contribution of radiative tail from the elastic peak is of particular importance, similar effects in the semi-inclusive process were only recently estimated in the peaking approximation. The explicit expressions for the lepton part of the lowest order QED contribution of exclusive radiative tail to the five-fold differential cross section are obtained and discussed. Numerical estimates, provided within Jefferson Lab kinematic conditions, demonstrate rather large effects of the exclusive radiative tail in the region at semi-inclusive threshold and for high energy of detected hadron.
|
1009.4545
|
Markus Bobrowski
|
Markus Bobrowski and Alexander Lenz
|
Charm mixing in the Standard Model
|
4 pages, talk at "35th International Conference on High Energy
Physics", Paris, France, July 22 -- 28, 2010
|
PoS ICHEP2010:193,2010
| null |
TTP10-39, DO-TH 10/15
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this talk we report on a study on the mixing of neutral charmed mesons and
argue that, at the present stage, a CP violating weak phase of the order of
some per mille can not be excluded in the Standard Model. It is shown how some,
seemingly reasonable, simplifying assumptions about CKM couplings lead to the
wrong conclusion that CP violation of this amount is an unambiguous indication
of new physics. The presented results rely on a recent short-distance analysis
of the Delta C=2 transition, which confirms the expectation that the dominant
contribution is due to effects of flavour symmetry breaking appearing in higher
orders of the Heavy Quark Expansion. We investigate meson-antimeson transitions
with an intermediate state coupling to the meson's sea quark background,
present in dimension 10 and 12, using a factorisation approach to simplify the
operator basis. On account of a lifting of GIM suppression by one power of
m_s/m_c, the contribution to y=Delta Gamma/2 Gamma is found to exceed that of
the formally leading dimension six by a factor close to ten.
|
[
{
"created": "Thu, 23 Sep 2010 09:05:08 GMT",
"version": "v1"
}
] |
2011-04-22
|
[
[
"Bobrowski",
"Markus",
""
],
[
"Lenz",
"Alexander",
""
]
] |
In this talk we report on a study on the mixing of neutral charmed mesons and argue that, at the present stage, a CP violating weak phase of the order of some per mille can not be excluded in the Standard Model. It is shown how some, seemingly reasonable, simplifying assumptions about CKM couplings lead to the wrong conclusion that CP violation of this amount is an unambiguous indication of new physics. The presented results rely on a recent short-distance analysis of the Delta C=2 transition, which confirms the expectation that the dominant contribution is due to effects of flavour symmetry breaking appearing in higher orders of the Heavy Quark Expansion. We investigate meson-antimeson transitions with an intermediate state coupling to the meson's sea quark background, present in dimension 10 and 12, using a factorisation approach to simplify the operator basis. On account of a lifting of GIM suppression by one power of m_s/m_c, the contribution to y=Delta Gamma/2 Gamma is found to exceed that of the formally leading dimension six by a factor close to ten.
|
1809.00242
|
Reza Khosravi
|
M. Janbazi, R. Khosravi and E. Noori
|
Analysis of $D^*_sD^*K^*$ and $ D_{s1} D_1 K^*$ vertices in three-point
sum rules
|
12 pages, 5 figures
|
Advances in High Energy Physics, Volume 2018, 6045932 (2018)
|
10.1155/2018/6045932
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this study, the coupling constant of $D^*_sD^*K^*$ and $D_{s1}D_1K^*$
vertices were determined within the three-point Quantum chromodynamics sum
rules method with and without consideration of the $SU_{f}(3)$ symmetry. The
coupling constants were calculated for off-shell charm and K$^*$ cases.
Considering the non-perturbative effect of the correlation function, as the
most important contribution, the quark-quark, quark-gluon, and gluon-gluon
condensate corrections were estimated and were compared with other predictive
methods.
|
[
{
"created": "Sat, 1 Sep 2018 19:52:40 GMT",
"version": "v1"
}
] |
2018-12-20
|
[
[
"Janbazi",
"M.",
""
],
[
"Khosravi",
"R.",
""
],
[
"Noori",
"E.",
""
]
] |
In this study, the coupling constant of $D^*_sD^*K^*$ and $D_{s1}D_1K^*$ vertices were determined within the three-point Quantum chromodynamics sum rules method with and without consideration of the $SU_{f}(3)$ symmetry. The coupling constants were calculated for off-shell charm and K$^*$ cases. Considering the non-perturbative effect of the correlation function, as the most important contribution, the quark-quark, quark-gluon, and gluon-gluon condensate corrections were estimated and were compared with other predictive methods.
|
hep-ph/9812439
|
Dan-Di Wu
|
Dan-Di Wu
|
Simple unitarity relations among charged current coupling constants
|
6 pages, Latex file
| null | null |
PVAMU-HEP-12-98
|
hep-ph
| null |
I suggest two new unitarity tests for the quark charged current coupling
constants which are $(sin \gamma/sin \alpha) = \zeta$, and $(sin 2\gamma)/(sin
2\alpha) = - ((1-\zeta cos \beta))/(cos \beta-\zeta)$ where $\zeta$ is a CKM
parameter defined in the text. These unitarity identities do not suffer some of
the multi-value ambiguities. Related problems are discussed. The sign of
$\Delta m_{_{B_d}}$ should satisfy the condition $\Delta m cos 2\beta < 0$.
|
[
{
"created": "Fri, 18 Dec 1998 20:16:13 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Wu",
"Dan-Di",
""
]
] |
I suggest two new unitarity tests for the quark charged current coupling constants which are $(sin \gamma/sin \alpha) = \zeta$, and $(sin 2\gamma)/(sin 2\alpha) = - ((1-\zeta cos \beta))/(cos \beta-\zeta)$ where $\zeta$ is a CKM parameter defined in the text. These unitarity identities do not suffer some of the multi-value ambiguities. Related problems are discussed. The sign of $\Delta m_{_{B_d}}$ should satisfy the condition $\Delta m cos 2\beta < 0$.
|
hep-ph/9903252
|
Tommy Ohlsson
|
Tommy Ohlsson, Hakan Snellman
|
Neutrino oscillations and mixings with three flavors
|
9 pages, 2 figures, RevTeX
|
Phys. Rev. D 60, 093007 (1999)
|
10.1103/PhysRevD.60.093007
| null |
hep-ph
| null |
Global fits to all data of candidates for neutrino oscillations are presented
in the framework of a three-flavor model. The analysis excludes mass regions
where the MSW effect is important for the solar neutrino problem. The best fit
gives $\theta_1 \approx 28.9^\circ, \theta_2 \approx 4.2^\circ, \theta_3
\approx 45.0^\circ, m_2^2 - m_1^2 \approx 2.87 \cdot 10^{-4} eV^2$, and $m_3^2
- m_2^2 \approx 1.11 eV^2$ indicating essentially maximal mixing between the
two lightest neutrino mass eigenstates.
|
[
{
"created": "Wed, 3 Mar 1999 20:59:13 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Nov 1999 17:37:44 GMT",
"version": "v2"
}
] |
2016-08-25
|
[
[
"Ohlsson",
"Tommy",
""
],
[
"Snellman",
"Hakan",
""
]
] |
Global fits to all data of candidates for neutrino oscillations are presented in the framework of a three-flavor model. The analysis excludes mass regions where the MSW effect is important for the solar neutrino problem. The best fit gives $\theta_1 \approx 28.9^\circ, \theta_2 \approx 4.2^\circ, \theta_3 \approx 45.0^\circ, m_2^2 - m_1^2 \approx 2.87 \cdot 10^{-4} eV^2$, and $m_3^2 - m_2^2 \approx 1.11 eV^2$ indicating essentially maximal mixing between the two lightest neutrino mass eigenstates.
|
1809.01923
|
Ilkay Turk Cakir
|
O. Cakir (Ankara University), A. Yilmaz (Giresun University), I. Turk
Cakir (Giresun University), A. Senol (Bolu Abant Izzet Baysal University), H.
Denizli (Bolu Abant Izzet Baysal University)
|
Probing Top Quark FCNC tqgamma and tqZ Couplings at Future
Electron-Proton Colliders
|
16 pages, 10 figures
| null |
10.1016/j.nuclphysb.2019.114640
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The top quark flavor changing neutral current (FCNC) processes are extremely
suppressed within the Standard Model (SM) of particle physics. However, they
could be enhanced in a new physics model Beyond the Standard Model (BSM). The
top quark FCNC interactions would be a good test of new physics at present and
future colliders. Within the framework of the BSM models, these interactions
can be described by an effective Lagrangian. In this work, we study tqgamma and
tqZ effective FCNC interaction vertices through the process e-p->e-Wq+X at
future electron proton colliders, projected as Large Hadron electron Collider
(LHeC) and Future Circular Collider-hadron electron (FCC-he). The cross
sections for the signal have been calculated for different values of parameters
lambda_q for tqgamma vertices and kappa_q for $tqZ$ vertices. Taking into
account the relevant background we estimate the attainable range of signal
parameters as a function of the integrated luminosity and present contour plots
of couplings for different significance levels including detector simulation.
|
[
{
"created": "Thu, 6 Sep 2018 11:09:29 GMT",
"version": "v1"
},
{
"created": "Sat, 26 Jan 2019 10:10:42 GMT",
"version": "v2"
}
] |
2019-06-26
|
[
[
"Cakir",
"O.",
"",
"Ankara University"
],
[
"Yilmaz",
"A.",
"",
"Giresun University"
],
[
"Cakir",
"I. Turk",
"",
"Giresun University"
],
[
"Senol",
"A.",
"",
"Bolu Abant Izzet Baysal University"
],
[
"Denizli",
"H.",
"",
"Bolu Abant Izzet Baysal University"
]
] |
The top quark flavor changing neutral current (FCNC) processes are extremely suppressed within the Standard Model (SM) of particle physics. However, they could be enhanced in a new physics model Beyond the Standard Model (BSM). The top quark FCNC interactions would be a good test of new physics at present and future colliders. Within the framework of the BSM models, these interactions can be described by an effective Lagrangian. In this work, we study tqgamma and tqZ effective FCNC interaction vertices through the process e-p->e-Wq+X at future electron proton colliders, projected as Large Hadron electron Collider (LHeC) and Future Circular Collider-hadron electron (FCC-he). The cross sections for the signal have been calculated for different values of parameters lambda_q for tqgamma vertices and kappa_q for $tqZ$ vertices. Taking into account the relevant background we estimate the attainable range of signal parameters as a function of the integrated luminosity and present contour plots of couplings for different significance levels including detector simulation.
|
1501.04014
|
Zhentao Zhang
|
Zhentao Zhang
|
Final state interactions at the threshold of Higgs boson pair production
|
5 pages
| null |
10.1088/0954-3899/42/11/115003
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the effect of final state interactions at the threshold of Higgs
boson pair production in the Glashow-Weinberg-Salam model. We consider three
major processes of the pair production in the model: lepton pair annihilation,
ZZ fusion, and WW fusion. We find that the corrections caused by the effect for
these processes are markedly different. According to our results, the effect
can cause non-negligible corrections to the cross sections for lepton pair
annihilation and small corrections for ZZ fusion, and this effect is negligible
for WW fusion.
|
[
{
"created": "Fri, 16 Jan 2015 15:29:35 GMT",
"version": "v1"
}
] |
2015-10-28
|
[
[
"Zhang",
"Zhentao",
""
]
] |
We study the effect of final state interactions at the threshold of Higgs boson pair production in the Glashow-Weinberg-Salam model. We consider three major processes of the pair production in the model: lepton pair annihilation, ZZ fusion, and WW fusion. We find that the corrections caused by the effect for these processes are markedly different. According to our results, the effect can cause non-negligible corrections to the cross sections for lepton pair annihilation and small corrections for ZZ fusion, and this effect is negligible for WW fusion.
|
2009.10974
|
Enrico Morgante
|
Nayara Fonseca, Enrico Morgante
|
Probing photophobic (rel)axion dark matter
| null |
Phys. Rev. D 103, 015011 (2021)
|
10.1103/PhysRevD.103.015011
|
MITP/20-042
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate the interplay between early universe cosmology and dark matter
direct detection, considering axion models with naturally suppressed couplings
to photons. In the context of the cosmological relaxation of the electroweak
scale, we focus on a scenario of \emph{Relaxion Dark Matter}, in which the
relaxion field constitutes all the observed dark matter relic density and its
allowed mass range is fixed to a few $\mathrm{keV}$ by construction. In
particular, we show that a relaxion particle with mass $m_\phi= 3.0
\,\mathrm{keV}$ which couples to electrons with $g_{\phi, e}= 6.8 \times
10^{-14}$ is consistent with the XENON1T excess, while accounting for the
observed dark matter and satisfying astro/cosmo probes. This scenario uses the
electroweak scale as the link connecting the relaxion production at early times
with the dark matter absorption rate in direct detection.
|
[
{
"created": "Wed, 23 Sep 2020 07:30:21 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Jan 2021 15:58:35 GMT",
"version": "v2"
}
] |
2021-01-26
|
[
[
"Fonseca",
"Nayara",
""
],
[
"Morgante",
"Enrico",
""
]
] |
We investigate the interplay between early universe cosmology and dark matter direct detection, considering axion models with naturally suppressed couplings to photons. In the context of the cosmological relaxation of the electroweak scale, we focus on a scenario of \emph{Relaxion Dark Matter}, in which the relaxion field constitutes all the observed dark matter relic density and its allowed mass range is fixed to a few $\mathrm{keV}$ by construction. In particular, we show that a relaxion particle with mass $m_\phi= 3.0 \,\mathrm{keV}$ which couples to electrons with $g_{\phi, e}= 6.8 \times 10^{-14}$ is consistent with the XENON1T excess, while accounting for the observed dark matter and satisfying astro/cosmo probes. This scenario uses the electroweak scale as the link connecting the relaxion production at early times with the dark matter absorption rate in direct detection.
|
hep-ph/9506333
|
Dirk Graudenz
|
D. Graudenz, M. Hampel, A. Vogt, Ch. Berger
|
The Mellin Transform Technique for the Extraction of the Gluon Density
|
13 pages (LaTeX); 2 figures are included via epsfig; the
corresponding postscript files are uuencoded
|
Z.Phys. C70 (1996) 77-82
| null |
CERN-TH/95-149, DESY-95-107
|
hep-ph hep-ex
| null |
A new method is presented to determine the gluon density in the proton from
jet production in deeply inelastic scattering. By using the technique of Mellin
transforms not only for the solution of the scale evolution equation of the
parton densities but also for the evaluation of scattering cross sections, the
gluon density can be extracted in next-to-leading order QCD. The method
described in this paper is, however, more general, and can be used in
situations where a repeated fast numerical evaluation of scattering cross
sections for varying parton distribution functions is required.
|
[
{
"created": "Thu, 15 Jun 1995 12:11:17 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Graudenz",
"D.",
""
],
[
"Hampel",
"M.",
""
],
[
"Vogt",
"A.",
""
],
[
"Berger",
"Ch.",
""
]
] |
A new method is presented to determine the gluon density in the proton from jet production in deeply inelastic scattering. By using the technique of Mellin transforms not only for the solution of the scale evolution equation of the parton densities but also for the evaluation of scattering cross sections, the gluon density can be extracted in next-to-leading order QCD. The method described in this paper is, however, more general, and can be used in situations where a repeated fast numerical evaluation of scattering cross sections for varying parton distribution functions is required.
|
1707.05592
|
Alba Soto-Ontoso
|
Javier L. Albacete, Hannah Petersen and Alba Soto-Ontoso
|
Symmetric cumulants as a probe of the proton substructure at LHC
energies
|
9 pages, 8 figures. New section on the number of subnucleonic
constituents of the proton added. Accepted for publication in PLB
| null |
10.1016/j.physletb.2018.01.011
| null |
hep-ph hep-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present a systematic study of the normalized symmetric cumulants,
NSC(n,m), at the eccentricity level in proton-proton interactions at $\sqrt
s\!=\! 13$ TeV within a wounded hot spot approach. We focus our attention on
the influence of spatial correlations between the proton constituents, in our
case gluonic hot spots, on this observable. We notice that the presence of
short-range repulsive correlations between the hot spots systematically
decreases the values of NSC(2,3) and NSC(2,4) in mid-to-ultra central
collisions while increases them in peripheral interactions. In the case of
NSC(2,3) we find that, as suggested by data, an anti-correlation of
$\varepsilon_2$ and $\varepsilon_3$ in ultra-central collisions, i.e.
NSC(2,3)$<0$, is possible within the correlated scenario while it never occurs
without correlations. We attribute this fact to the decisive role of
correlations on enlarging the probability of interaction topologies that reduce
the value of NSC(2,3) and, eventually, make it negative. Further, we explore
the dependence of our conclusions on the values of the hot spot radius and the
repulsive core distance. Our results add evidence to the idea that considering
spatial correlations between the subnucleonic degrees of freedom of the proton
may have a strong impact on the initial state properties of proton-proton
interactions [1].
|
[
{
"created": "Tue, 18 Jul 2017 12:55:48 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Jan 2018 09:42:43 GMT",
"version": "v2"
}
] |
2018-02-01
|
[
[
"Albacete",
"Javier L.",
""
],
[
"Petersen",
"Hannah",
""
],
[
"Soto-Ontoso",
"Alba",
""
]
] |
We present a systematic study of the normalized symmetric cumulants, NSC(n,m), at the eccentricity level in proton-proton interactions at $\sqrt s\!=\! 13$ TeV within a wounded hot spot approach. We focus our attention on the influence of spatial correlations between the proton constituents, in our case gluonic hot spots, on this observable. We notice that the presence of short-range repulsive correlations between the hot spots systematically decreases the values of NSC(2,3) and NSC(2,4) in mid-to-ultra central collisions while increases them in peripheral interactions. In the case of NSC(2,3) we find that, as suggested by data, an anti-correlation of $\varepsilon_2$ and $\varepsilon_3$ in ultra-central collisions, i.e. NSC(2,3)$<0$, is possible within the correlated scenario while it never occurs without correlations. We attribute this fact to the decisive role of correlations on enlarging the probability of interaction topologies that reduce the value of NSC(2,3) and, eventually, make it negative. Further, we explore the dependence of our conclusions on the values of the hot spot radius and the repulsive core distance. Our results add evidence to the idea that considering spatial correlations between the subnucleonic degrees of freedom of the proton may have a strong impact on the initial state properties of proton-proton interactions [1].
|
hep-ph/9802369
|
Richard Lebed
|
W. W. Buck and Richard F. Lebed
|
New Constraints on Dispersive Form Factor Parameterizations from the
Timelike Region
|
24 pages, latex (revtex), 3 eps figures
|
Phys.Rev.D58:056001,1998
|
10.1103/PhysRevD.58.056001
|
JLAB-THY-98-04
|
hep-ph
| null |
We generalize a recent model-independent form factor parameterization derived
from rigorous dispersion relations to include constraints from data in the
timelike region. These constraints dictate the convergence properties of the
parameterization and appear as sum rules on the parameters. We further develop
a new parameterization that takes into account finiteness and asymptotic
conditions on the form factor, and use it to fit to the elastic \pi
electromagnetic form factor. We find that the existing world sample of timelike
data gives only loose bounds on the form factor in the spacelike region, but
explain how the acquisition of additional timelike data or fits to other form
factors are expected to give much better results. The same parameterization is
seen to fit spacelike data extremely well.
|
[
{
"created": "Fri, 20 Feb 1998 00:12:44 GMT",
"version": "v1"
}
] |
2014-11-17
|
[
[
"Buck",
"W. W.",
""
],
[
"Lebed",
"Richard F.",
""
]
] |
We generalize a recent model-independent form factor parameterization derived from rigorous dispersion relations to include constraints from data in the timelike region. These constraints dictate the convergence properties of the parameterization and appear as sum rules on the parameters. We further develop a new parameterization that takes into account finiteness and asymptotic conditions on the form factor, and use it to fit to the elastic \pi electromagnetic form factor. We find that the existing world sample of timelike data gives only loose bounds on the form factor in the spacelike region, but explain how the acquisition of additional timelike data or fits to other form factors are expected to give much better results. The same parameterization is seen to fit spacelike data extremely well.
|
1911.09202
|
Stanislaw Jadach
|
Stanis{\l}aw Jadach and Maciej Skrzypek
|
Theory challenges at future lepton colliders
|
submitted to Acta Physica Polonica B
| null |
10.5506/APhysPolB.50.1705
|
IFJPAN-IV-2019-16
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
High energy, high luminosity, future lepton colliders, circular or linear,
may possibly give us hint about fundamental laws of Nature governing at very
short distances and very short time intervals, the same which have brought our
Universe to live. Currently considered projects are on one hand linear
electron-positron colliders, which offer higher energy and lower beam
intensities and on the other hand circular electron-positron colliders, limited
in energy but offering tremendous interaction rates. On the far future horizon,
muon circular colliders are the only viable projects which can explore $>10$TeV
teritory of the lepton colliders. Experiments in all these future colliders
will require theoretical calculations, mainly of Standard Model processes
(including QED), at the precision level one or even two orders better than
available today. After briefly characterization of theory puzzles in the
fundamental interactions we shall overview main challenges in the precision
calculations of the Standard Model effects, which have to be removed from data,
in order to reveal traces of new unexpected phenomena.
|
[
{
"created": "Wed, 20 Nov 2019 22:53:31 GMT",
"version": "v1"
}
] |
2020-02-19
|
[
[
"Jadach",
"Stanisław",
""
],
[
"Skrzypek",
"Maciej",
""
]
] |
High energy, high luminosity, future lepton colliders, circular or linear, may possibly give us hint about fundamental laws of Nature governing at very short distances and very short time intervals, the same which have brought our Universe to live. Currently considered projects are on one hand linear electron-positron colliders, which offer higher energy and lower beam intensities and on the other hand circular electron-positron colliders, limited in energy but offering tremendous interaction rates. On the far future horizon, muon circular colliders are the only viable projects which can explore $>10$TeV teritory of the lepton colliders. Experiments in all these future colliders will require theoretical calculations, mainly of Standard Model processes (including QED), at the precision level one or even two orders better than available today. After briefly characterization of theory puzzles in the fundamental interactions we shall overview main challenges in the precision calculations of the Standard Model effects, which have to be removed from data, in order to reveal traces of new unexpected phenomena.
|
1805.06490
|
Hazhar Ghaderi
|
Hazhar Ghaderi
|
Octet and decuplet contribution to the proton self energy
|
32 pages, 10 figures, fixed Ref.-format, added a Ref., fixed a couple
of irrelevant typos
| null | null | null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
Within the hadronic language of Chiral Perturbation Theory we present the
full leading-order octet-baryon$-$meson and decuplet-baryon$-$meson
contribution to the proton self energy and thus to its wave function
renormalization factor $Z$. By Fock-expanding the physical proton state into
its bare and hadron-cloud part, we show how each individual baryon-meson
probability depend on the average momenta of the particles in the fluctuation.
We present how the results depend on the choice of the form factor involved in
the regularization (Gaussian or Besselian) and how they depend on the cut-off
parameter. We also show how the results vary with respect to a variation of the
decuplet coupling constant $h_A$. The momentum distributions of the
fluctuations are given and the fluctuations' relative probabilities are
presented.
We show that for reasonable values of the cut-off parameter, the Delta-pion
fluctuation is of the same strength as the nucleon-pion fluctuation.
|
[
{
"created": "Wed, 16 May 2018 18:53:19 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Jul 2018 03:17:47 GMT",
"version": "v2"
}
] |
2018-07-19
|
[
[
"Ghaderi",
"Hazhar",
""
]
] |
Within the hadronic language of Chiral Perturbation Theory we present the full leading-order octet-baryon$-$meson and decuplet-baryon$-$meson contribution to the proton self energy and thus to its wave function renormalization factor $Z$. By Fock-expanding the physical proton state into its bare and hadron-cloud part, we show how each individual baryon-meson probability depend on the average momenta of the particles in the fluctuation. We present how the results depend on the choice of the form factor involved in the regularization (Gaussian or Besselian) and how they depend on the cut-off parameter. We also show how the results vary with respect to a variation of the decuplet coupling constant $h_A$. The momentum distributions of the fluctuations are given and the fluctuations' relative probabilities are presented. We show that for reasonable values of the cut-off parameter, the Delta-pion fluctuation is of the same strength as the nucleon-pion fluctuation.
|
2010.10062
|
Chen Gang
|
Zhen Zhang, Liang Zheng, Gang Chen, Hong-Ge Xu, Dai-Mei Zhou, Yu-Liang
Yan and Ben-Hao Sa
|
The study of exotic state $Z_c^{\pm}(3900)$ decaying to
$J/\psi\pi^{\pm}$ in the $pp$ collisions at $\sqrt{s}$ = 1.96, 7, and 13 TeV
|
6 pages,5 figures
|
Eur.Phys.J.C(2021)81:198
|
10.1140/epjc/s10052-021-08983-3
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A dynamically constrained phase-space coalescence model plus PACIAE model was
used to predict the exotic resonant state $Z_c^{\pm}(3900)$ yield, transverse
momentum distribution, and the rapidity distribution with $|y| < 6$ and $p_T <
10$ GeV/c in $pp$ collisions at $\sqrt{s} = 1.96, 7$ and 13 TeV, respectively.
The yield of the $Z_c^{\pm}(3900)$ is estimated to be around $10^{-6}$ to
$10^{-5}$. We also present the energy dependence of the transverse momentum
distributions and rapidity distributions for ${Z_c^{+}(3900)}$ and
${Z_c^{-}(3900)}$. The production of ${Z_c^{+}(3900)}$ and its anti-particle
${Z_c^{-}(3900)}$ is found to be quite similar to each other.
|
[
{
"created": "Tue, 20 Oct 2020 06:42:55 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Mar 2021 12:34:21 GMT",
"version": "v2"
},
{
"created": "Tue, 2 Mar 2021 09:56:16 GMT",
"version": "v3"
}
] |
2021-03-03
|
[
[
"Zhang",
"Zhen",
""
],
[
"Zheng",
"Liang",
""
],
[
"Chen",
"Gang",
""
],
[
"Xu",
"Hong-Ge",
""
],
[
"Zhou",
"Dai-Mei",
""
],
[
"Yan",
"Yu-Liang",
""
],
[
"Sa",
"Ben-Hao",
""
]
] |
A dynamically constrained phase-space coalescence model plus PACIAE model was used to predict the exotic resonant state $Z_c^{\pm}(3900)$ yield, transverse momentum distribution, and the rapidity distribution with $|y| < 6$ and $p_T < 10$ GeV/c in $pp$ collisions at $\sqrt{s} = 1.96, 7$ and 13 TeV, respectively. The yield of the $Z_c^{\pm}(3900)$ is estimated to be around $10^{-6}$ to $10^{-5}$. We also present the energy dependence of the transverse momentum distributions and rapidity distributions for ${Z_c^{+}(3900)}$ and ${Z_c^{-}(3900)}$. The production of ${Z_c^{+}(3900)}$ and its anti-particle ${Z_c^{-}(3900)}$ is found to be quite similar to each other.
|
hep-ph/9504314
| null |
Gautam Bhattacharyya, Debajyoti Choudhury and K. Sridhar
|
New LEP bounds on $B$-violating scalar couplings: R-parity violating
supersymmetry or diquarks
|
LaTeX, 12 pages, 4 figures (uuencoded compressed postscript files
added through "figures" option)
|
Phys.Lett. B355 (1995) 193-198
|
10.1016/0370-2693(95)00701-L
|
preprint CERN-TH/95-89
|
hep-ph
| null |
We use the precision electroweak data at LEP to place bounds on $B$-violating
Yukawa couplings, two theoretically appealing examples being provided by
$R$-parity--violating supersymmetry and diquarks. The couplings involving the
third generation quarks are most severely constrained. These bounds are
complementary to those obtained from low-energy processes.
|
[
{
"created": "Mon, 17 Apr 1995 14:13:23 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Bhattacharyya",
"Gautam",
""
],
[
"Choudhury",
"Debajyoti",
""
],
[
"Sridhar",
"K.",
""
]
] |
We use the precision electroweak data at LEP to place bounds on $B$-violating Yukawa couplings, two theoretically appealing examples being provided by $R$-parity--violating supersymmetry and diquarks. The couplings involving the third generation quarks are most severely constrained. These bounds are complementary to those obtained from low-energy processes.
|
hep-ph/9610484
|
Herbert Weigel
|
T. Haberichter, H. Reinhardt, N. N. Scoccola and H. Weigel
|
Strangeness Dependence in Radiative Hyperon Decay Amplitudes
|
15 pages Latex, no figures
|
Nucl.Phys. A615 (1997) 291-304
|
10.1016/S0375-9474(96)00485-X
|
UNITU--THEP--21/1996, TAN-FNT-96/007
|
hep-ph
| null |
The radiative decays of the $(3/2)^+$ baryons are studied in the three flavor
generalization of the Skyrme model. The kaon fields are treated in the slow
rotator approach which properly accounts for the observed deviations from the
$U$-spin relations for the hyperon magnetic moments. This makes possible a
critical discussion of the $U$-spin selection rules for the radiative hyperon
decays. The variation of the decay widths with strangeness is studied and a
comparison with other treatments of the $SU(3)$ Skyrme model is performed in
order to analyze the effects of flavor symmetry breaking.
|
[
{
"created": "Fri, 25 Oct 1996 08:33:37 GMT",
"version": "v1"
}
] |
2016-09-06
|
[
[
"Haberichter",
"T.",
""
],
[
"Reinhardt",
"H.",
""
],
[
"Scoccola",
"N. N.",
""
],
[
"Weigel",
"H.",
""
]
] |
The radiative decays of the $(3/2)^+$ baryons are studied in the three flavor generalization of the Skyrme model. The kaon fields are treated in the slow rotator approach which properly accounts for the observed deviations from the $U$-spin relations for the hyperon magnetic moments. This makes possible a critical discussion of the $U$-spin selection rules for the radiative hyperon decays. The variation of the decay widths with strangeness is studied and a comparison with other treatments of the $SU(3)$ Skyrme model is performed in order to analyze the effects of flavor symmetry breaking.
|
2106.15622
|
Shashank Shalgar
|
Shashank Shalgar and Irene Tamborra
|
Symmetry breaking induced by pairwise conversion of neutrinos in compact
sources
|
9 pages, 6 figures, revtex4-1 two column format. Version accepted in
Phys. Rev. D. Supplmental material:
https://sid.erda.dk/share_redirect/hwp0WKuuk7/index.html
| null |
10.1103/PhysRevD.105.043018
| null |
hep-ph astro-ph.HE
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A surprising consequence of non-linear flavor evolution is the spontaneous
breaking of the initial symmetries of the neutrino gas propagating in a dense
astrophysical environment.
We explore the flavor conversion physics by taking into account the polar and
azimuthal angular distributions of neutrinos and present the very first example
of spontaneous symmetry breaking in the context of fast flavor mixing in the
nonlinear regime. Intriguingly, we find that fast flavor mixing does not always
develop in the proximity of the angular regions with vanishing electron lepton
number, as commonly assumed, and large flavor mixing can rapidly spread through
all neutrino modes. Such behavior cannot be predicted from the linear regime of
the flavor evolution. These results can have major consequences on the physics
of compact astrophysical objects.
|
[
{
"created": "Tue, 29 Jun 2021 18:00:00 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Feb 2022 13:58:06 GMT",
"version": "v2"
}
] |
2022-03-09
|
[
[
"Shalgar",
"Shashank",
""
],
[
"Tamborra",
"Irene",
""
]
] |
A surprising consequence of non-linear flavor evolution is the spontaneous breaking of the initial symmetries of the neutrino gas propagating in a dense astrophysical environment. We explore the flavor conversion physics by taking into account the polar and azimuthal angular distributions of neutrinos and present the very first example of spontaneous symmetry breaking in the context of fast flavor mixing in the nonlinear regime. Intriguingly, we find that fast flavor mixing does not always develop in the proximity of the angular regions with vanishing electron lepton number, as commonly assumed, and large flavor mixing can rapidly spread through all neutrino modes. Such behavior cannot be predicted from the linear regime of the flavor evolution. These results can have major consequences on the physics of compact astrophysical objects.
|
0707.4464
|
Vincenzo Cirigliano
|
Vincenzo Cirigliano and Ignasi Rosell
|
pi/K -> e nu branching ratios to O(e^2 p^4) in Chiral Perturbation
Theory
|
40 pages, 4 figures, 3 tables
|
JHEP 0710:005,2007
|
10.1088/1126-6708/2007/10/005
|
LAUR-07-4532
|
hep-ph
| null |
We calculate the ratios R_{e/mu}^{(P)} = Gamma(P -> e nu)/Gamma (P -> mu nu)
(P=pi,K) in Chiral Perturbation Theory to order e^2 p^4. We complement the one-
and two-loop effective theory results with a matching calculation of the local
counterterm, performed within the large-$N_C$ expansion. We find
R_{e/mu}^{(\pi)} = (1.2352 \pm 0.0001)*10^{-4} and R_{e/mu}^{(K)} = (2.477 \pm
0.001)*10^{-5}, with uncertainty induced by the matching procedure and chiral
power counting. Given the sensitivity of upcoming new measurements, our results
provide a clean baseline to detect or constrain effects from weak-scale new
physics in these rare decays. As a by-product, we also update the theoretical
analysis of the individual pi/K -> \ell nu modes.
|
[
{
"created": "Mon, 30 Jul 2007 18:24:48 GMT",
"version": "v1"
}
] |
2009-02-18
|
[
[
"Cirigliano",
"Vincenzo",
""
],
[
"Rosell",
"Ignasi",
""
]
] |
We calculate the ratios R_{e/mu}^{(P)} = Gamma(P -> e nu)/Gamma (P -> mu nu) (P=pi,K) in Chiral Perturbation Theory to order e^2 p^4. We complement the one- and two-loop effective theory results with a matching calculation of the local counterterm, performed within the large-$N_C$ expansion. We find R_{e/mu}^{(\pi)} = (1.2352 \pm 0.0001)*10^{-4} and R_{e/mu}^{(K)} = (2.477 \pm 0.001)*10^{-5}, with uncertainty induced by the matching procedure and chiral power counting. Given the sensitivity of upcoming new measurements, our results provide a clean baseline to detect or constrain effects from weak-scale new physics in these rare decays. As a by-product, we also update the theoretical analysis of the individual pi/K -> \ell nu modes.
|
hep-ph/9804261
|
Patrick J. O'Donnell
|
Jacqueline Faridani, Smaragda Lola, Patrick J. O'Donnell and Utpal
Sarkar
|
Scale of Leptogenesis
|
13 pages, 7 figures, plain Latex
|
Eur.Phys.J.C7:543-549,1999
|
10.1007/s100529901020
|
UTPT-98-05
|
hep-ph
| null |
We study the scale at which one can generate the lepton asymmetry of the
universe which could then get converted to a baryon asymmetry during the
electroweak phase transition. We consider the possibility that the Yukawa
couplings are small but sufficiently large to generate enough lepton asymmetry.
This forbids the possibility of the $(B-L)$ breaking scale being the
electroweak scale.
|
[
{
"created": "Wed, 8 Apr 1998 17:47:35 GMT",
"version": "v1"
}
] |
2011-09-13
|
[
[
"Faridani",
"Jacqueline",
""
],
[
"Lola",
"Smaragda",
""
],
[
"O'Donnell",
"Patrick J.",
""
],
[
"Sarkar",
"Utpal",
""
]
] |
We study the scale at which one can generate the lepton asymmetry of the universe which could then get converted to a baryon asymmetry during the electroweak phase transition. We consider the possibility that the Yukawa couplings are small but sufficiently large to generate enough lepton asymmetry. This forbids the possibility of the $(B-L)$ breaking scale being the electroweak scale.
|
hep-ph/9911210
|
K. Goulianos
|
Konstantin Goulianos
|
Pomeron: Beyond the Standard Approach
|
6 pages, Latex, one figure
| null | null | null |
hep-ph
| null |
We discuss the experimental evidence supporting the concept of universality
of the rapidity gap probability in soft and hard diffraction, relate the gap
probability to hadronic parton densities, and present a phenomenological model
of diffraction in which the structure of the Pomeron is derived from the
structure of the parent hadron. Predictions for diffractive deep inelastic
scattering are compared with data.
|
[
{
"created": "Tue, 2 Nov 1999 19:07:06 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Goulianos",
"Konstantin",
""
]
] |
We discuss the experimental evidence supporting the concept of universality of the rapidity gap probability in soft and hard diffraction, relate the gap probability to hadronic parton densities, and present a phenomenological model of diffraction in which the structure of the Pomeron is derived from the structure of the parent hadron. Predictions for diffractive deep inelastic scattering are compared with data.
|
hep-ph/9906282
|
Philip Page
|
Leonid Burakovsky and Philip R. Page
|
Tensor glueball-meson mixing phenomenology
|
Main text 18 pages, LaTeX. Minor changes
|
Eur.Phys.J.C12:489-498,2000
|
10.1007/s100529900281
|
LA-UR-99-2905
|
hep-ph nucl-th
| null |
The overpopulated isoscalar tensor states are sifted using Schwinger-type
mass relations. Two solutions are found: one where the glueball is the
fJ(2220), and one where the glueball is more distributed, with f2(1820) having
the largest component. The f2(1565) and fJ(1710) cannot be accommodated as
glueball-(hybrid) meson mixtures in the absense of significant coupling to
decay channels. f2'(1525) -> pi pi is in agreement with experiment. The
fJ(2220) decays neither flavour democratically nor is narrow.
|
[
{
"created": "Tue, 8 Jun 1999 00:00:07 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Mar 2000 19:02:12 GMT",
"version": "v2"
}
] |
2011-09-13
|
[
[
"Burakovsky",
"Leonid",
""
],
[
"Page",
"Philip R.",
""
]
] |
The overpopulated isoscalar tensor states are sifted using Schwinger-type mass relations. Two solutions are found: one where the glueball is the fJ(2220), and one where the glueball is more distributed, with f2(1820) having the largest component. The f2(1565) and fJ(1710) cannot be accommodated as glueball-(hybrid) meson mixtures in the absense of significant coupling to decay channels. f2'(1525) -> pi pi is in agreement with experiment. The fJ(2220) decays neither flavour democratically nor is narrow.
|
1010.6174
|
Alexander Bakulev P.
|
Alexander P. Bakulev
|
Two-loop Resummation in Fractional Analytic Perturbation Theory
|
11 pages; 3 figures; invited talk given at the 16th International
Seminar "Quarks-2010", Kolomna (Russia), June 6--12, 2010
| null |
10.1142/9789814329682_0075
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
This talk describes the resummation approach in (Fractional) Analytic
Perturbation Theory (FAPT) in QCD. First, we make a short historical review of
the (F)APT approach and then shortly describe the global scheme of FAPT which
allows one to take into account heavy-quark thresholds. After that we show how
it is possible to resum a non-power series in (F)APT both in the one- and
two-loop approximations. As an application we suggest our analysis of the Higgs
boson decay ${H^0\to b\bar{b}}$, important for the LHC program, and of the
vector-current Adler function.
|
[
{
"created": "Fri, 29 Oct 2010 10:27:58 GMT",
"version": "v1"
}
] |
2017-08-23
|
[
[
"Bakulev",
"Alexander P.",
""
]
] |
This talk describes the resummation approach in (Fractional) Analytic Perturbation Theory (FAPT) in QCD. First, we make a short historical review of the (F)APT approach and then shortly describe the global scheme of FAPT which allows one to take into account heavy-quark thresholds. After that we show how it is possible to resum a non-power series in (F)APT both in the one- and two-loop approximations. As an application we suggest our analysis of the Higgs boson decay ${H^0\to b\bar{b}}$, important for the LHC program, and of the vector-current Adler function.
|
2012.03988
|
Lu\'is Ventura
|
Miguel Levy, Jo\~ao G. Rosa, Luis B. Ventura
|
Warm Inflation, Neutrinos and Dark matter: a minimal extension of the
Standard Model
|
43 pages (30 main + 13 appendices), 8 figures. Comments are welcome
| null |
10.1007/JHEP12(2021)176
| null |
hep-ph astro-ph.CO gr-qc
|
http://creativecommons.org/licenses/by/4.0/
|
We show that warm inflation can be realized within a minimal extension of the
Standard Model with three right-handed neutrinos, three complex scalars and a
gauged lepton/B-L U(1) symmetry. This simple model can address all the
shortcomings of the Standard Model that are not related to fine-tuning, within
general relativity, with distinctive experimental signatures that can be probed
in the near future. The inflaton field emerges from the collective breaking of
the U(1) symmetry, and interacts with two of the right-handed neutrinos,
sustaining a high-temperature radiation bath during inflation. The discrete
interchange symmetry of the model protects the scalar potential against large
thermal corrections and leads to a stable inflaton remnant at late times which
can account for dark matter. Consistency of the model and agreement with Cosmic
Microwave Background observations naturally yield light neutrino masses below
0.1 eV, while thermal leptogenesis occurs naturally after a smooth exit from
inflation into the radiation era.
|
[
{
"created": "Mon, 7 Dec 2020 19:02:08 GMT",
"version": "v1"
}
] |
2022-01-05
|
[
[
"Levy",
"Miguel",
""
],
[
"Rosa",
"João G.",
""
],
[
"Ventura",
"Luis B.",
""
]
] |
We show that warm inflation can be realized within a minimal extension of the Standard Model with three right-handed neutrinos, three complex scalars and a gauged lepton/B-L U(1) symmetry. This simple model can address all the shortcomings of the Standard Model that are not related to fine-tuning, within general relativity, with distinctive experimental signatures that can be probed in the near future. The inflaton field emerges from the collective breaking of the U(1) symmetry, and interacts with two of the right-handed neutrinos, sustaining a high-temperature radiation bath during inflation. The discrete interchange symmetry of the model protects the scalar potential against large thermal corrections and leads to a stable inflaton remnant at late times which can account for dark matter. Consistency of the model and agreement with Cosmic Microwave Background observations naturally yield light neutrino masses below 0.1 eV, while thermal leptogenesis occurs naturally after a smooth exit from inflation into the radiation era.
|
hep-ph/9411249
| null |
Zurab Berezhiani and Enrico Nardi
|
Natural R Parity Conservation with Horizontal Symmetries. a Four
Generation Model
|
Revised version : improved analysis of the horizontal gauge groups.
One numerical error corrected. 21 pages, LaTex, no figures
|
Phys. Rev. D 52, 3087 (1995)
|
10.1103/PhysRevD.52.3087
|
UM-TH-94-36 and INFN-FE-06-94
|
hep-ph
| null |
In most supersymmetric models the stability of the proton is ensured by
invoking R-parity. A necessary ingredient to enforce R-parity is the
possibility of distinguishing the lepton superfields from the Higgs ones. This
is generally achieved either by assuming different charges under some matter
parity, or by assigning the superfields to different representations of a
unified gauge group. We want to put forward the idea that the replica of the
fermion generations, which constitute an intrinsic difference between the
fermions and the Higgs superfields, can give a clue to understand R-parity as
an accidental symmetry. More ambitiously, we suggest a possible relation
between proton stability and the actual number of fermion generations. We carry
out our investigation in the framework of non-Abelian horizontal gauge
symmetries. We identify $SU(4)_H$ as the only acceptable horizontal gauge group
whichcan naturally ensure the absence of R parity violating operators, without
conflicting with other theoretical and phenomenological constraints. We analyze
a version of the supersymmetric standard model equipped with a gauged
horizontal $SU(4)_H$, in which R-parity is accidental. The model predicts four
families of fermions, it allows for the dynamical generation of a realistic
hierarchy of fermion masseswithout any ad hoc choice of small Yukawa couplings,
it ensures in a natural way the heaviness of all the fourth family fermions
(including the neutrino) and it predicts a {\it lower} limit for the
$\tau$-neutrino mass of a few eV. The scale of the breaking of the horizontal
symmetry can be constrained rather precisely in a narrow window around $\sim
10^{11}$ GeV. Some interesting astrophysical and cosmological implications of
the model are addressed as well.
|
[
{
"created": "Tue, 8 Nov 1994 20:24:01 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Mar 1995 02:38:27 GMT",
"version": "v2"
}
] |
2016-08-24
|
[
[
"Berezhiani",
"Zurab",
""
],
[
"Nardi",
"Enrico",
""
]
] |
In most supersymmetric models the stability of the proton is ensured by invoking R-parity. A necessary ingredient to enforce R-parity is the possibility of distinguishing the lepton superfields from the Higgs ones. This is generally achieved either by assuming different charges under some matter parity, or by assigning the superfields to different representations of a unified gauge group. We want to put forward the idea that the replica of the fermion generations, which constitute an intrinsic difference between the fermions and the Higgs superfields, can give a clue to understand R-parity as an accidental symmetry. More ambitiously, we suggest a possible relation between proton stability and the actual number of fermion generations. We carry out our investigation in the framework of non-Abelian horizontal gauge symmetries. We identify $SU(4)_H$ as the only acceptable horizontal gauge group whichcan naturally ensure the absence of R parity violating operators, without conflicting with other theoretical and phenomenological constraints. We analyze a version of the supersymmetric standard model equipped with a gauged horizontal $SU(4)_H$, in which R-parity is accidental. The model predicts four families of fermions, it allows for the dynamical generation of a realistic hierarchy of fermion masseswithout any ad hoc choice of small Yukawa couplings, it ensures in a natural way the heaviness of all the fourth family fermions (including the neutrino) and it predicts a {\it lower} limit for the $\tau$-neutrino mass of a few eV. The scale of the breaking of the horizontal symmetry can be constrained rather precisely in a narrow window around $\sim 10^{11}$ GeV. Some interesting astrophysical and cosmological implications of the model are addressed as well.
|
hep-ph/0506081
|
Pedro Brogueira
|
Pedro Brogueira, Jorge Dias de Deus
|
Multiplicity fluctuations and percolation of strings in hadron-hadron
and nucleus-nucleus collisions
|
11 pages, 5 eps figures, latex
|
Phys.Rev. C72 (2005) 044903
|
10.1103/PhysRevC.72.044903
| null |
hep-ph
| null |
We argue that recent NA49 results on multiparticle distributions and
fluctuations, as a function of the number of participant nucleons, suggest that
percolation plays an important role in particle production at high densities.
|
[
{
"created": "Wed, 8 Jun 2005 12:05:52 GMT",
"version": "v1"
}
] |
2009-11-11
|
[
[
"Brogueira",
"Pedro",
""
],
[
"de Deus",
"Jorge Dias",
""
]
] |
We argue that recent NA49 results on multiparticle distributions and fluctuations, as a function of the number of participant nucleons, suggest that percolation plays an important role in particle production at high densities.
|
2107.11951
|
Satyabrata Mahapatra
|
Purusottam Ghosh (1), Satyabrata Mahapatra (2), Nimmala Narendra (3),
Narendra Sahu (2) ((1) Harish-Chandra Research Institute, India (2) Indian
Institute of Technology Hyderabad, India (3) Physical Research Laboratory,
India)
|
TeV Scale Modified Type-II Seesaw and Dark Matter in a Gauged $U(1)_{\rm
B-L}$ Symmetric Model
|
52 Pages, 23 captioned figures, Version accepted for publication in
Phys. Rev. D
| null |
10.1103/PhysRevD.106.015001
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In an endeavor to explain the light neutrino masses and dark matter (DM)
simultaneously, we study a gauged $U(1)_{\rm B-L}$ extension of the standard
model (SM). The neutrino masses are generated through a variant of type-II
seesaw mechanism in which one of the scalar triplets has a mass in a scale that
is accessible at the present generation colliders. Three SM singlet right
chiral fermions $\chi_{iR}$($i=e,\mu,\tau$) with $\rm B-L$ charges -4, -4, +5
are invoked to cancel the $\rm B-L$ gauge anomalies and the lightest one among
these three fermions becomes a viable DM candidate as their stability is
guaranteed by a remnant $\mathcal Z_2$ symmetry to which $U(1)_{\rm B-L}$ gauge
symmetry gets spontaneously broken. Interestingly in this scenario, the
neutrino mass and the co-annihilation of DM are interlinked through the
breaking of $U(1)_{\rm B-L}$ symmetry. Apart from giving rise to the observed
neutrino mass and dark matter abundance, the model also predicts exciting
signals at the colliders. Especially we see a significant enhancement in the
production cross-section of the TeV scale doubly charged scalar in presence of
the $Z_{\rm BL}$ gauge boson. We discuss all the relevant constraints on model
parameters from observed DM abundance and null detection of DM at direct and
indirect search experiments as well as the constraints on the $\rm B-L$ gauge
boson from recent colliders.
|
[
{
"created": "Mon, 26 Jul 2021 04:14:27 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Jun 2022 10:21:31 GMT",
"version": "v2"
}
] |
2022-07-20
|
[
[
"Ghosh",
"Purusottam",
""
],
[
"Mahapatra",
"Satyabrata",
""
],
[
"Narendra",
"Nimmala",
""
],
[
"Sahu",
"Narendra",
""
]
] |
In an endeavor to explain the light neutrino masses and dark matter (DM) simultaneously, we study a gauged $U(1)_{\rm B-L}$ extension of the standard model (SM). The neutrino masses are generated through a variant of type-II seesaw mechanism in which one of the scalar triplets has a mass in a scale that is accessible at the present generation colliders. Three SM singlet right chiral fermions $\chi_{iR}$($i=e,\mu,\tau$) with $\rm B-L$ charges -4, -4, +5 are invoked to cancel the $\rm B-L$ gauge anomalies and the lightest one among these three fermions becomes a viable DM candidate as their stability is guaranteed by a remnant $\mathcal Z_2$ symmetry to which $U(1)_{\rm B-L}$ gauge symmetry gets spontaneously broken. Interestingly in this scenario, the neutrino mass and the co-annihilation of DM are interlinked through the breaking of $U(1)_{\rm B-L}$ symmetry. Apart from giving rise to the observed neutrino mass and dark matter abundance, the model also predicts exciting signals at the colliders. Especially we see a significant enhancement in the production cross-section of the TeV scale doubly charged scalar in presence of the $Z_{\rm BL}$ gauge boson. We discuss all the relevant constraints on model parameters from observed DM abundance and null detection of DM at direct and indirect search experiments as well as the constraints on the $\rm B-L$ gauge boson from recent colliders.
|
1207.4619
|
Mikhail Zubkov
|
M. A. Zubkov
|
Application of nonperturbative methods to the investigation of strong,
electroweak, and gravitational interactions
|
Doctor of science (Habilitation) thesis, 246 pages, in russian
| null | null | null |
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Nonperturbative lattice methods are applied to the investigation of strong,
electroweak, and gravitational interactions. Selected models of new physics
(expected at the TeV scale) are discussed.
|
[
{
"created": "Thu, 19 Jul 2012 11:47:00 GMT",
"version": "v1"
}
] |
2012-07-20
|
[
[
"Zubkov",
"M. A.",
""
]
] |
Nonperturbative lattice methods are applied to the investigation of strong, electroweak, and gravitational interactions. Selected models of new physics (expected at the TeV scale) are discussed.
|
2404.01388
|
Igor Shovkovy
|
Ritesh Ghosh and Igor A. Shovkovy
|
Electrical conductivity of hot relativistic plasma in a strong magnetic
field
|
6 pages, 2 figures; v2: corrected numerical data for conductivities,
updated figures and supplementary material
| null | null | null |
hep-ph hep-th nucl-th
|
http://creativecommons.org/licenses/by-nc-sa/4.0/
|
We employ first-principles quantum field theoretical methods to investigate
the longitudinal and transverse electrical conductivities of a strongly
magnetized hot QED plasma at the leading order in coupling. The analysis
utilized the fermion damping rate in the Landau-level representation obtained
recently. In the relativistic regime, both conductivities exhibit an
approximate scaling behavior given by $\sigma_{\parallel,\perp} = T
\tilde{\sigma}_{\parallel,\perp}$, where $\tilde{\sigma}_{\parallel,\perp}$ are
functions of the dimensionless ratio $|eB|/T^2$ (here $T$ denotes the
temperature and $B$ the magnetic field). We argue that the mechanisms for the
transverse and longitudinal conductivities differ significantly, leading to a
strong suppression of the former in comparison to the latter. Additionally, we
extend our analysis to a magnetized quark-gluon plasma, although the
approximation's validity breaks down in QCD at strong coupling.
|
[
{
"created": "Mon, 1 Apr 2024 18:00:20 GMT",
"version": "v1"
},
{
"created": "Fri, 10 May 2024 21:53:46 GMT",
"version": "v2"
}
] |
2024-05-14
|
[
[
"Ghosh",
"Ritesh",
""
],
[
"Shovkovy",
"Igor A.",
""
]
] |
We employ first-principles quantum field theoretical methods to investigate the longitudinal and transverse electrical conductivities of a strongly magnetized hot QED plasma at the leading order in coupling. The analysis utilized the fermion damping rate in the Landau-level representation obtained recently. In the relativistic regime, both conductivities exhibit an approximate scaling behavior given by $\sigma_{\parallel,\perp} = T \tilde{\sigma}_{\parallel,\perp}$, where $\tilde{\sigma}_{\parallel,\perp}$ are functions of the dimensionless ratio $|eB|/T^2$ (here $T$ denotes the temperature and $B$ the magnetic field). We argue that the mechanisms for the transverse and longitudinal conductivities differ significantly, leading to a strong suppression of the former in comparison to the latter. Additionally, we extend our analysis to a magnetized quark-gluon plasma, although the approximation's validity breaks down in QCD at strong coupling.
|
0911.3026
|
Francesco Becattini
|
F. Becattini (University of Florence, Italy), P. Castorina (University
of Catania, Italy), A. Milov (Weizmann Institute of Science, Israel), H. Satz
(University of Bielefeld, Germany)
|
A comparative analysis of statistical hadron production
|
14 pages, 2 figures. Revised version accepted for publication in Eur.
Phys. J. C
|
Eur.Phys.J.C66:377-386,2010
|
10.1140/epjc/s10052-010-1265-y
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We perform a systematic comparison of the statistical model parametrization
of hadron abundances measured in high energy pp, AA and e+e- collisions. The
basic aim of the study is to test if the quality of the description depends on
the nature of the collision process. In particular, we want to see if nuclear
collisions, with multiple initial interactions, lead to "more thermal" average
multiplicities than elementary pp collisions or e+e- annihilation. Such a
comparison is meaningful only if it is based on data for the same or similar
hadronic species and if the analyzed data has quantitatively similar errors.
When these requirements are maintained, the quality of the statistical model
description is found to be the same for the different initial collision
configurations.
|
[
{
"created": "Mon, 16 Nov 2009 13:29:28 GMT",
"version": "v1"
},
{
"created": "Tue, 9 Feb 2010 09:17:50 GMT",
"version": "v2"
}
] |
2014-11-20
|
[
[
"Becattini",
"F.",
"",
"University of Florence, Italy"
],
[
"Castorina",
"P.",
"",
"University\n of Catania, Italy"
],
[
"Milov",
"A.",
"",
"Weizmann Institute of Science, Israel"
],
[
"Satz",
"H.",
"",
"University of Bielefeld, Germany"
]
] |
We perform a systematic comparison of the statistical model parametrization of hadron abundances measured in high energy pp, AA and e+e- collisions. The basic aim of the study is to test if the quality of the description depends on the nature of the collision process. In particular, we want to see if nuclear collisions, with multiple initial interactions, lead to "more thermal" average multiplicities than elementary pp collisions or e+e- annihilation. Such a comparison is meaningful only if it is based on data for the same or similar hadronic species and if the analyzed data has quantitatively similar errors. When these requirements are maintained, the quality of the statistical model description is found to be the same for the different initial collision configurations.
|
hep-ph/9905503
|
Willy van Neerven
|
W.L. van Neerven
|
Deep inelastic lepton-hadron scattering as a test of perturbative QCD
|
15 pages, LaTeX. To appear in the proceedings of the workshop DIS99,
DESY-Zeuthen, Germany, April 19-23, 1999. To be published in Nucl. Phys.
Proc. Suppl. C
|
Nucl.Phys.Proc.Suppl. 79 (1999) 36-50
|
10.1016/S0920-5632(99)00636-2
| null |
hep-ph
| null |
Exploration of the small $x$ kinematic region by the HERA experiments led to
a revival of some models which existed before the advent of Quantum Chromo
Dynamics (QCD) as the theory of the strong interactions. Predictions of these
models for the deep inelastic structure functions are compared with those given
by QCD. Future experiments will concentrate on the large $x$-region and we will
discuss some issues which are important for the test of QCD. In particular we
emphasize the next-to-next-to-leading (NNLO) order analysis of the structure
functions and the determination of the strong coupling constant $\alpha_s$. We
also make some critical remarks about the relevance of so called large
corrections in the small and large $x$-region.
|
[
{
"created": "Thu, 27 May 1999 09:43:09 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"van Neerven",
"W. L.",
""
]
] |
Exploration of the small $x$ kinematic region by the HERA experiments led to a revival of some models which existed before the advent of Quantum Chromo Dynamics (QCD) as the theory of the strong interactions. Predictions of these models for the deep inelastic structure functions are compared with those given by QCD. Future experiments will concentrate on the large $x$-region and we will discuss some issues which are important for the test of QCD. In particular we emphasize the next-to-next-to-leading (NNLO) order analysis of the structure functions and the determination of the strong coupling constant $\alpha_s$. We also make some critical remarks about the relevance of so called large corrections in the small and large $x$-region.
|
hep-ph/0208021
|
O. V. Kancheli
|
O.V. Kancheli
|
Parton picture of inelastic collisions at transplanckian energies
|
25 pages, 7 figures
| null | null | null |
hep-ph gr-qc hep-th
| null |
We propose a parton model of inelastic collisions at transplanckian energies
E >> G^{-1/2}, using the gravitons, whose transverse momenta are cut at the
Planck scale, as partons. For this purpose we represent the gravitational
shock-wave accompanying the fast particle in terms of such partons and take
into account the higher order multiperipheral-like contributions. We argue that
the internal part of this shock plane contains the ``black'' disk of radius
R(E) ~ E^{1/2} filled by such hard partons with the Planck density. When two
fast particles collide the hard graviton production comes from the region of
intersection of their black disks. The corresponding value of inclusive
cross-section at the given rapidity and the impact parameter is proportional to
the area of this region. The final state with such hard gravitons is unstable
relative to the long range gravitational repulsion, and this leads to the
creation of the multiperipheral chain of black holes at later stages of the
reaction. We discuss various details of this picture including higher order
corrections and there connection to a purely classical approach; we also
consider briefly possible changes when additional hidden dimensions are
present.
|
[
{
"created": "Fri, 2 Aug 2002 12:07:35 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Kancheli",
"O. V.",
""
]
] |
We propose a parton model of inelastic collisions at transplanckian energies E >> G^{-1/2}, using the gravitons, whose transverse momenta are cut at the Planck scale, as partons. For this purpose we represent the gravitational shock-wave accompanying the fast particle in terms of such partons and take into account the higher order multiperipheral-like contributions. We argue that the internal part of this shock plane contains the ``black'' disk of radius R(E) ~ E^{1/2} filled by such hard partons with the Planck density. When two fast particles collide the hard graviton production comes from the region of intersection of their black disks. The corresponding value of inclusive cross-section at the given rapidity and the impact parameter is proportional to the area of this region. The final state with such hard gravitons is unstable relative to the long range gravitational repulsion, and this leads to the creation of the multiperipheral chain of black holes at later stages of the reaction. We discuss various details of this picture including higher order corrections and there connection to a purely classical approach; we also consider briefly possible changes when additional hidden dimensions are present.
|
1310.8152
|
Talal Ahmed Chowdhury
|
Shehu S. AbdusSalam and Talal Ahmed Chowdhury
|
Scalar Representations in the Light of Electroweak Phase Transition and
Cold Dark Matter Phenomenology
|
typos corrected and added references
| null |
10.1088/1475-7516/2014/05/026
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The extension of the standard model's minimal Higgs sector with an inert
$SU(2)_L$ scalar doublet can provide light dark matter candidate and
simultaneously induce a strong phase transition for explaining Baryogenesis.
There is however no symmetry reasons to prevent the extension using scalars
with higher $SU(2)_L$ representations. By making random scans over the models'
parameters, we show that in the light of electroweak physics constraints,
strong first order electroweak phase transition and the possibility of having
sub-TeV cold dark matter candidate the higher representations are rather
disfavored compared to the inert doublet. This is done by computing generic
perturbativity behavior and impact on electroweak phase transitions of higher
representations in comparison with the inert doublet model. Explicit phase
transition and cold dark matter phenomenology within the context of the inert
triplet and quartet representations are used for detailed illustrations.
|
[
{
"created": "Wed, 30 Oct 2013 13:45:26 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Feb 2014 19:02:53 GMT",
"version": "v2"
}
] |
2015-06-17
|
[
[
"AbdusSalam",
"Shehu S.",
""
],
[
"Chowdhury",
"Talal Ahmed",
""
]
] |
The extension of the standard model's minimal Higgs sector with an inert $SU(2)_L$ scalar doublet can provide light dark matter candidate and simultaneously induce a strong phase transition for explaining Baryogenesis. There is however no symmetry reasons to prevent the extension using scalars with higher $SU(2)_L$ representations. By making random scans over the models' parameters, we show that in the light of electroweak physics constraints, strong first order electroweak phase transition and the possibility of having sub-TeV cold dark matter candidate the higher representations are rather disfavored compared to the inert doublet. This is done by computing generic perturbativity behavior and impact on electroweak phase transitions of higher representations in comparison with the inert doublet model. Explicit phase transition and cold dark matter phenomenology within the context of the inert triplet and quartet representations are used for detailed illustrations.
|
2311.00021
|
Tom Tong
|
Vincenzo Cirigliano, Wouter Dekens, Jordy de Vries, Emanuele
Mereghetti, Tom Tong
|
Anomalies in global SMEFT analyses: a case study of first-row CKM
unitarity
|
70 pages, 16 figures, Supplemental Material included in ancillary
files
| null | null | null |
hep-ph hep-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Recent developments in the Standard Model analysis of semileptonic
charged-current processes involving light quarks have revealed $\sim 3\sigma$
tensions in Cabibbo universality tests involving meson, neutron, and nuclear
beta decays. In this paper, we explore beyond the Standard Model explanations
of this so-called Cabibbo Angle Anomaly in the framework of the Standard Model
Effective Field Theory (SMEFT), including not only low-energy charged current
processes (`L'), but also electroweak precision observables (`EW') and
Drell-Yan collider processes (`C') that probe the same underlying physics
across a broad range of energy scales. The resulting `CLEW' framework not only
allows one to test explanations of the Cabibbo Angle Anomaly, but is set up to
provide near model-independent analyses with minimal assumptions on the flavor
structure of the SMEFT operators. Besides the global analysis, we consider a
large number of simpler scenarios, each with a subset of SMEFT operators, and
investigate how much they improve upon the Standard Model fit. We find that the
most favored scenarios, as judged by the Akaike Information Criterion, are
those that involve right-handed charged currents. Additional interactions,
namely oblique operators, terms modifying the Fermi constant, and operators
involving right-handed neutral currents, play a role if the CDF determination
of the $W$ mass is included in the analysis.
|
[
{
"created": "Tue, 31 Oct 2023 18:00:00 GMT",
"version": "v1"
}
] |
2023-11-02
|
[
[
"Cirigliano",
"Vincenzo",
""
],
[
"Dekens",
"Wouter",
""
],
[
"de Vries",
"Jordy",
""
],
[
"Mereghetti",
"Emanuele",
""
],
[
"Tong",
"Tom",
""
]
] |
Recent developments in the Standard Model analysis of semileptonic charged-current processes involving light quarks have revealed $\sim 3\sigma$ tensions in Cabibbo universality tests involving meson, neutron, and nuclear beta decays. In this paper, we explore beyond the Standard Model explanations of this so-called Cabibbo Angle Anomaly in the framework of the Standard Model Effective Field Theory (SMEFT), including not only low-energy charged current processes (`L'), but also electroweak precision observables (`EW') and Drell-Yan collider processes (`C') that probe the same underlying physics across a broad range of energy scales. The resulting `CLEW' framework not only allows one to test explanations of the Cabibbo Angle Anomaly, but is set up to provide near model-independent analyses with minimal assumptions on the flavor structure of the SMEFT operators. Besides the global analysis, we consider a large number of simpler scenarios, each with a subset of SMEFT operators, and investigate how much they improve upon the Standard Model fit. We find that the most favored scenarios, as judged by the Akaike Information Criterion, are those that involve right-handed charged currents. Additional interactions, namely oblique operators, terms modifying the Fermi constant, and operators involving right-handed neutral currents, play a role if the CDF determination of the $W$ mass is included in the analysis.
|
1201.0197
|
Andreas Crivellin
|
Andreas Crivellin
|
Flavor violation in the MSSM and implications for top and squark
searches at colliders
|
11 pages, 4 figures. Presented at Linear Collider 2011: Understanding
QCD at Linear Colliders in searching for old and new physics, 12-16 September
2011, ECT*, Trento, Italy
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this article I review some connections between flavor physics and collider
physics. The first part discusses the effect of right-handed charged currents
on the determination of the CKM elements V_ub. It is shown that such an
effective right-handed W-coupling can be generated in the MSSM which would lead
to a sizable enhancement of single-top production at the LHC. The second part
of this article focuses on the constraints on the mass splitting between
left-handed squarks from Kaon and D mixing. Such a mass splitting has
interesting consequences for squark decay chains at colliders.
|
[
{
"created": "Fri, 30 Dec 2011 23:19:36 GMT",
"version": "v1"
}
] |
2012-01-04
|
[
[
"Crivellin",
"Andreas",
""
]
] |
In this article I review some connections between flavor physics and collider physics. The first part discusses the effect of right-handed charged currents on the determination of the CKM elements V_ub. It is shown that such an effective right-handed W-coupling can be generated in the MSSM which would lead to a sizable enhancement of single-top production at the LHC. The second part of this article focuses on the constraints on the mass splitting between left-handed squarks from Kaon and D mixing. Such a mass splitting has interesting consequences for squark decay chains at colliders.
|
1206.3605
|
Mauricio B. Magro
|
F. de Campos, O. J. P. \'Eboli, M. B. Magro, W. Porod, D. Restrepo, S.
P. Das, M. Hirsch and J. W. F. Valle
|
Probing neutralino properties in minimal supergravity with bilinear
R-parity violation
|
12 pages, 11 figures
| null |
10.1103/PhysRevD.86.075001
|
IFIC/12-45
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Supersymmetric models with bilinear R-parity violation (BRPV) can account for
the observed neutrino masses and mixing parameters indicated by neutrino
oscillation data. We consider minimal supergravity versions of BRPV where the
lightest supersymmetric particle (LSP) is a neutralino. This is unstable, with
a large enough decay length to be detected at the CERN Large Hadron Collider
(LHC). We analyse the LHC potential to determine the LSP properties, such as
mass, lifetime and branching ratios, and discuss their relation to neutrino
properties.
|
[
{
"created": "Fri, 15 Jun 2012 22:51:37 GMT",
"version": "v1"
}
] |
2013-05-30
|
[
[
"de Campos",
"F.",
""
],
[
"Éboli",
"O. J. P.",
""
],
[
"Magro",
"M. B.",
""
],
[
"Porod",
"W.",
""
],
[
"Restrepo",
"D.",
""
],
[
"Das",
"S. P.",
""
],
[
"Hirsch",
"M.",
""
],
[
"Valle",
"J. W. F.",
""
]
] |
Supersymmetric models with bilinear R-parity violation (BRPV) can account for the observed neutrino masses and mixing parameters indicated by neutrino oscillation data. We consider minimal supergravity versions of BRPV where the lightest supersymmetric particle (LSP) is a neutralino. This is unstable, with a large enough decay length to be detected at the CERN Large Hadron Collider (LHC). We analyse the LHC potential to determine the LSP properties, such as mass, lifetime and branching ratios, and discuss their relation to neutrino properties.
|
1107.0771
|
Yingchuan Li
|
Hye-Sung Lee, Yingchuan Li
|
Identifying Sneutrino Dark Matter: Interplay between the LHC and Direct
Search
|
5 pages, 3 figures
| null |
10.1103/PhysRevD.84.095003
| null |
hep-ph
|
http://creativecommons.org/licenses/by/3.0/
|
Under R-parity, the lightest supersymmetric particle (LSP) is stable and may
serve as a good dark matter candidate. The R-parity can be naturally introduced
with a gauge origin at TeV scale. We go over why a TeV scale B-L gauge
extension of the minimal supersymmetric standard model (MSSM) is one of the
most natural, if not demanded, low energy supersymmetric models. In the
presence of a TeV scale Abelian gauge symmetry, the (predominantly)
right-handed sneutrino LSP can be a good dark matter candidate. Its
identification at the LHC is challenging because it does not carry any standard
model charge. We show how we can use the correlation between the LHC
experiments (dilepton resonance signals) and the direct dark matter search
experiments (such as CDMS and XENON) to identify the right-handed sneutrino LSP
dark matter in the B-L extended MSSM.
|
[
{
"created": "Tue, 5 Jul 2011 02:54:29 GMT",
"version": "v1"
}
] |
2013-05-29
|
[
[
"Lee",
"Hye-Sung",
""
],
[
"Li",
"Yingchuan",
""
]
] |
Under R-parity, the lightest supersymmetric particle (LSP) is stable and may serve as a good dark matter candidate. The R-parity can be naturally introduced with a gauge origin at TeV scale. We go over why a TeV scale B-L gauge extension of the minimal supersymmetric standard model (MSSM) is one of the most natural, if not demanded, low energy supersymmetric models. In the presence of a TeV scale Abelian gauge symmetry, the (predominantly) right-handed sneutrino LSP can be a good dark matter candidate. Its identification at the LHC is challenging because it does not carry any standard model charge. We show how we can use the correlation between the LHC experiments (dilepton resonance signals) and the direct dark matter search experiments (such as CDMS and XENON) to identify the right-handed sneutrino LSP dark matter in the B-L extended MSSM.
|
1811.10619
|
Eduardo Peinado
|
Leon M.G. de la Vega, R. Ferro-Hernandez, E. Peinado
|
Simple A4 models for dark matter stability with texture zeros
|
5 pages, 1 figure. Minor corrections, some references added, version
to match the journal version
|
Phys. Rev. D 99, 055044 (2019)
|
10.1103/PhysRevD.99.055044
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In a simple framework which naturally incorporates dark matter stability and
neutrino phenomenology, we compute all the possible texture zeros which arise
when the non-abelian flavor symmetry A4 is spontaneously broken to Z2. As a
result, we obtain four textures with two vanishing matrix elements. Two of such
textures predict a zero contribution to the neutrinoless double beta decay
effective mass parameter at tree level, and as a one loop bound we get
$m_{ee}<8\times 10^{-2}$ meV. These are compatible with the normal ordering for
the neutrino masses and the allowed range for the lightest neutrino mass is
between $m_{\nu_{min}}\sim3$ meV and $m_{\nu_{max}}\sim8$ meV. Additionally we
obtain dark matter stability linked to the way the flavor symmetry is broken,
leaving a residual Z2 symmetry
|
[
{
"created": "Mon, 26 Nov 2018 19:00:01 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Mar 2019 23:00:38 GMT",
"version": "v2"
}
] |
2019-04-01
|
[
[
"de la Vega",
"Leon M. G.",
""
],
[
"Ferro-Hernandez",
"R.",
""
],
[
"Peinado",
"E.",
""
]
] |
In a simple framework which naturally incorporates dark matter stability and neutrino phenomenology, we compute all the possible texture zeros which arise when the non-abelian flavor symmetry A4 is spontaneously broken to Z2. As a result, we obtain four textures with two vanishing matrix elements. Two of such textures predict a zero contribution to the neutrinoless double beta decay effective mass parameter at tree level, and as a one loop bound we get $m_{ee}<8\times 10^{-2}$ meV. These are compatible with the normal ordering for the neutrino masses and the allowed range for the lightest neutrino mass is between $m_{\nu_{min}}\sim3$ meV and $m_{\nu_{max}}\sim8$ meV. Additionally we obtain dark matter stability linked to the way the flavor symmetry is broken, leaving a residual Z2 symmetry
|
2106.12559
|
Markus Huber Q.
|
Martin Napetschnig, Reinhard Alkofer, Markus Q. Huber, Jan M.
Pawlowski
|
Yang-Mills propagators in linear covariant gauges from Nielsen
identities
|
14 pages, 14 figures
|
Phys. Rev. D 104, 054003 (2021)
|
10.1103/PhysRevD.104.054003
| null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
We calculate gluon and ghost propagators in Yang-Mills theory in linear
covariant gauges. To that end, we utilize Nielsen identities with Landau gauge
propagators and vertices as the starting point. We present and discuss
numerical results for the gluon and ghost propagators for values of the gauge
parameter $0<\xi \le 5$. Extrapolating the propagators to $\xi \to \infty $ we
find the expected qualitative behavior. We provide arguments that our results
are quantitatively reliable at least for values $\xi\lesssim 1/2$ of the gauge
fixing parameter. It is shown that the correlation functions, and in particular
the ghost propagator, change significantly with increasing gauge parameter. In
turn, the ghost-gluon running coupling as well as the position of the zero
crossing of the Schwinger function of the gluon propagator remain within the
uncertainties of our calculation unchanged.
|
[
{
"created": "Wed, 23 Jun 2021 17:37:23 GMT",
"version": "v1"
}
] |
2021-09-08
|
[
[
"Napetschnig",
"Martin",
""
],
[
"Alkofer",
"Reinhard",
""
],
[
"Huber",
"Markus Q.",
""
],
[
"Pawlowski",
"Jan M.",
""
]
] |
We calculate gluon and ghost propagators in Yang-Mills theory in linear covariant gauges. To that end, we utilize Nielsen identities with Landau gauge propagators and vertices as the starting point. We present and discuss numerical results for the gluon and ghost propagators for values of the gauge parameter $0<\xi \le 5$. Extrapolating the propagators to $\xi \to \infty $ we find the expected qualitative behavior. We provide arguments that our results are quantitatively reliable at least for values $\xi\lesssim 1/2$ of the gauge fixing parameter. It is shown that the correlation functions, and in particular the ghost propagator, change significantly with increasing gauge parameter. In turn, the ghost-gluon running coupling as well as the position of the zero crossing of the Schwinger function of the gluon propagator remain within the uncertainties of our calculation unchanged.
|
1212.2734
|
Alessandro Papa
|
Dmitry Yu. Ivanov and Alessandro Papa
|
Inclusive production of a pair of identified, rapidity-separated hadrons
in proton collisions
|
4 pages, presented at the International Workshop 'Diffraction 2012',
Puerto del Carmen (Spain), September 10-15, 2012
| null |
10.1063/1.4802168
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider the inclusive process where a pair of identified hadrons having
large transverse momenta is produced in high-energy proton-proton collisions.
We concentrate on the kinematics where the two identified hadrons in the final
state are separated by a large interval of rapidity. In this case the cross
section receives large higher-order corrections, which can be resummed in the
BFKL approach. We provide a theoretical input for the resummation of such
contributions with next-to-leading logarithmic accuracy. This process has much
in common with the widely discussed Mueller-Navelet jets production and can be
also used to access the BFKL dynamics at proton colliders.
|
[
{
"created": "Wed, 12 Dec 2012 08:44:11 GMT",
"version": "v1"
}
] |
2015-06-12
|
[
[
"Ivanov",
"Dmitry Yu.",
""
],
[
"Papa",
"Alessandro",
""
]
] |
We consider the inclusive process where a pair of identified hadrons having large transverse momenta is produced in high-energy proton-proton collisions. We concentrate on the kinematics where the two identified hadrons in the final state are separated by a large interval of rapidity. In this case the cross section receives large higher-order corrections, which can be resummed in the BFKL approach. We provide a theoretical input for the resummation of such contributions with next-to-leading logarithmic accuracy. This process has much in common with the widely discussed Mueller-Navelet jets production and can be also used to access the BFKL dynamics at proton colliders.
|
1705.04252
|
Alexei Smirnov Yu
|
A. N. Ioannisian and A.Yu. Smirnov
|
Attenuation effect and neutrino oscillation tomography
|
24 pages, 8 figures, typos corrected, more explanations added
|
Phys. Rev. D 96, 083009 (2017)
|
10.1103/PhysRevD.96.083009
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Attenuation effect is the effect of weakening of contributions to the
oscillation signal from remote structures of matter density profile. The effect
is a consequence of integration over the neutrino energy within the energy
resolution interval. Structures of a density profile situated at distances
larger than the attenuation length, $\lambda_{att}$, are not "seen". We show
that the origins of attenuation are (i) averaging of oscillations in certain
layer(s) of matter, (ii) smallness of matter effect: $\epsilon \equiv
2EV/\Delta m^2 \ll 1$, where $V$ is the matter potential, and (iii) specific
initial and final states on neutrinos. We elaborate on the graphic description
of the attenuation which allows us to compute explicitly the effects in the
$\epsilon^2$ order for various density profiles and oscillation channels. The
attenuation in the case of partial averaging is described. The effect is
crucial for interpretation of oscillation data and for the oscillation
tomography of the Earth with low energy (solar, supernova, atmospheric, {\it
etc.}) neutrinos.
|
[
{
"created": "Thu, 11 May 2017 15:51:26 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Jun 2017 08:31:29 GMT",
"version": "v2"
}
] |
2017-10-18
|
[
[
"Ioannisian",
"A. N.",
""
],
[
"Smirnov",
"A. Yu.",
""
]
] |
Attenuation effect is the effect of weakening of contributions to the oscillation signal from remote structures of matter density profile. The effect is a consequence of integration over the neutrino energy within the energy resolution interval. Structures of a density profile situated at distances larger than the attenuation length, $\lambda_{att}$, are not "seen". We show that the origins of attenuation are (i) averaging of oscillations in certain layer(s) of matter, (ii) smallness of matter effect: $\epsilon \equiv 2EV/\Delta m^2 \ll 1$, where $V$ is the matter potential, and (iii) specific initial and final states on neutrinos. We elaborate on the graphic description of the attenuation which allows us to compute explicitly the effects in the $\epsilon^2$ order for various density profiles and oscillation channels. The attenuation in the case of partial averaging is described. The effect is crucial for interpretation of oscillation data and for the oscillation tomography of the Earth with low energy (solar, supernova, atmospheric, {\it etc.}) neutrinos.
|
1008.2155
|
Jens Braun
|
Jens Braun, Bertram Klein, Piotr Piasecki
|
On the scaling behavior of the chiral phase transition in QCD in finite
and infinite volume
|
26 pages, 6 figures, 1 table
|
Eur.Phys.J.C71:1576,2011
|
10.1140/epjc/s10052-011-1576-7
| null |
hep-ph hep-lat
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the scaling behavior of the two-flavor chiral phase transition using
an effective quark-meson model. We investigate the transition between
infinite-volume and finite-volume scaling behavior when the system is placed in
a finite box. We can estimate effects that the finite volume and the explicit
symmetry breaking by the current quark masses have on the scaling behavior
which is observed in full QCD lattice simulations. The model allows us to
explore large quark masses as well as the chiral limit in a wide range of
volumes, and extract information about the scaling regimes.In particular, we
find large scaling deviations for physical pion masses and significant finite
volume effects for pion masses that are used in current lattice simulations.
|
[
{
"created": "Thu, 12 Aug 2010 16:03:17 GMT",
"version": "v1"
}
] |
2011-03-14
|
[
[
"Braun",
"Jens",
""
],
[
"Klein",
"Bertram",
""
],
[
"Piasecki",
"Piotr",
""
]
] |
We study the scaling behavior of the two-flavor chiral phase transition using an effective quark-meson model. We investigate the transition between infinite-volume and finite-volume scaling behavior when the system is placed in a finite box. We can estimate effects that the finite volume and the explicit symmetry breaking by the current quark masses have on the scaling behavior which is observed in full QCD lattice simulations. The model allows us to explore large quark masses as well as the chiral limit in a wide range of volumes, and extract information about the scaling regimes.In particular, we find large scaling deviations for physical pion masses and significant finite volume effects for pion masses that are used in current lattice simulations.
|
hep-ph/9810419
|
Pham Q. Hung
|
P. Q. Hung
|
On Neutrino Masses and Family Replication
|
RevTex, 12 pages with 1 figure, minor changes to the text and added
acknowledgments
|
Phys.Rev. D59 (1999) 113008
|
10.1103/PhysRevD.59.113008
|
UVA_INPP_98-8
|
hep-ph
| null |
The old issue of why there are more than one family of quarks and leptons is
reinvestigated with an eye towards the use of anomaly as a tool for
constraining the number of families. It is found that, by assuming the
existence of right-handed neutrinos (which would imply that neutrinos will have
a mass) and a new chiral SU(2) gauge theory, strong constraints on the number
of families can be obtained. In addition, a model, based on that extra SU(2),
is constructed where it is natural to have one "very heavy" fourth neutrino and
three almost degenerate light neutrinos whose masses are all of the Dirac type.
|
[
{
"created": "Tue, 20 Oct 1998 15:35:28 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Oct 1998 02:31:54 GMT",
"version": "v2"
},
{
"created": "Fri, 23 Oct 1998 17:28:51 GMT",
"version": "v3"
}
] |
2009-10-31
|
[
[
"Hung",
"P. Q.",
""
]
] |
The old issue of why there are more than one family of quarks and leptons is reinvestigated with an eye towards the use of anomaly as a tool for constraining the number of families. It is found that, by assuming the existence of right-handed neutrinos (which would imply that neutrinos will have a mass) and a new chiral SU(2) gauge theory, strong constraints on the number of families can be obtained. In addition, a model, based on that extra SU(2), is constructed where it is natural to have one "very heavy" fourth neutrino and three almost degenerate light neutrinos whose masses are all of the Dirac type.
|
0907.4786
|
Gabriel S\'anchez-Col\'on
|
Virendra Gupta and Gabriel S\'anchez-Col\'on
|
Some results for the wave function at the origin for S-wave levels
| null | null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Starting with the $S$-wave radial equation for an attractive central
potential $V(r)$, we give results for the $n$ (principal quantum number) and
the $\mu$ (reduced mass) dependence of $R_{n0}(0)$, the $S$-wave radial
wavefunction at the origin, for potentials with definite curvature.
|
[
{
"created": "Mon, 27 Jul 2009 22:24:59 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Apr 2013 19:19:01 GMT",
"version": "v2"
}
] |
2013-04-04
|
[
[
"Gupta",
"Virendra",
""
],
[
"Sánchez-Colón",
"Gabriel",
""
]
] |
Starting with the $S$-wave radial equation for an attractive central potential $V(r)$, we give results for the $n$ (principal quantum number) and the $\mu$ (reduced mass) dependence of $R_{n0}(0)$, the $S$-wave radial wavefunction at the origin, for potentials with definite curvature.
|
2212.10659
|
Delon Shen
|
Peter Onyisi, Delon Shen, Jesse Thaler
|
Comparing Point Cloud Strategies for Collider Event Classification
|
19 pages, 7 figures, 3 tables, code available at
https://github.com/DelonShen/classifying-collider-events-with-point-clouds;
v2: to match published version
|
Phys. Rev. D 108, 012001 (2023)
|
10.1103/PhysRevD.108.012001
|
MIT-CTP 5473
|
hep-ph hep-ex physics.data-an
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this paper, we compare several event classification architectures defined
on the point cloud representation of collider events. These approaches, which
are based on the frameworks of deep sets and edge convolutions, circumvent many
of the difficulties associated with traditional feature engineering. To
benchmark our architectures against more traditional event classification
strategies, we perform a case study involving Higgs boson decays to tau
leptons. We find a 2.5 times increase in performance compared to a baseline
ATLAS analysis with engineered features. Our point cloud architectures can be
viewed as simplified versions of graph neural networks, where each particle in
the event corresponds to a graph node. In our case study, we find the best
balance of performance and computational cost for simple pairwise
architectures, which are based on learned edge features.
|
[
{
"created": "Tue, 20 Dec 2022 21:22:09 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Jul 2023 07:43:39 GMT",
"version": "v2"
}
] |
2023-07-19
|
[
[
"Onyisi",
"Peter",
""
],
[
"Shen",
"Delon",
""
],
[
"Thaler",
"Jesse",
""
]
] |
In this paper, we compare several event classification architectures defined on the point cloud representation of collider events. These approaches, which are based on the frameworks of deep sets and edge convolutions, circumvent many of the difficulties associated with traditional feature engineering. To benchmark our architectures against more traditional event classification strategies, we perform a case study involving Higgs boson decays to tau leptons. We find a 2.5 times increase in performance compared to a baseline ATLAS analysis with engineered features. Our point cloud architectures can be viewed as simplified versions of graph neural networks, where each particle in the event corresponds to a graph node. In our case study, we find the best balance of performance and computational cost for simple pairwise architectures, which are based on learned edge features.
|
0901.1120
|
John Ellis
|
John Ellis
|
Outlook for Charged Higgs Physics
|
15 pages, 10 figures, uses PoS.cls
|
PoS CHARGED2008:040,2008
| null |
CERN-PH-TH/2009-004
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Almost all extensions of the Standard Model predict the existence of charged
Higgs bosons. This talk focuses on the minimal supersymmetric extension of the
Standard Model (MSSM), which is relatively predictive. The outlook for
detecting supersymmetric particles and Higgs bosons at the LHC are discussed,
as are the prospects for finding indirect effects of supersymmetric Higgs
bosons at low energies, e.g., in K decays. The outlook for discovering
observable effects of CP-violating supersymmetric phases at high energies or in
B decays is also mentioned.
|
[
{
"created": "Thu, 8 Jan 2009 20:01:58 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Jan 2009 18:48:29 GMT",
"version": "v2"
}
] |
2011-01-27
|
[
[
"Ellis",
"John",
""
]
] |
Almost all extensions of the Standard Model predict the existence of charged Higgs bosons. This talk focuses on the minimal supersymmetric extension of the Standard Model (MSSM), which is relatively predictive. The outlook for detecting supersymmetric particles and Higgs bosons at the LHC are discussed, as are the prospects for finding indirect effects of supersymmetric Higgs bosons at low energies, e.g., in K decays. The outlook for discovering observable effects of CP-violating supersymmetric phases at high energies or in B decays is also mentioned.
|
hep-ph/0012255
|
Rizos John
|
G.K. Leontaris (Univ. of Ioannina) and J. Rizos (Univ. of Ioannina and
CPHT)
|
A Pati-Salam model from branes
|
14 pages, 1 figure, final version to be published in Phys. Lett. B
|
Phys.Lett.B510:295-304,2001
|
10.1016/S0370-2693(01)00592-5
|
CPHT-S-093-12-00
|
hep-ph hep-th
| null |
We explore the possibility of embedding the Pati-Salam model in the context
of Type I brane models. We study a generic model with U(4)_C x U(2)_L x U(2)_R
gauge symmetry and matter fields compatible with a Type I brane configuration.
Examining the anomaly cancellation conditions of the surplus abelian symmetries
we find an alternative hypercharge embedding that is compatible with a low
string/brane scale of the order of 5-7 TeV, when the U(4)_C and U(2)_R brane
stack couplings are equal. Proton stability is assured as baryon number is
associated to a global symmetry remnant of the broken abelian factors. It is
also shown that this scenario can accommodate an extra low energy abelian
symmetry that can be associated to lepton number. The issue of fermion and
especially neutrino masses is also discussed.
|
[
{
"created": "Tue, 19 Dec 2000 20:51:29 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Jan 2001 17:08:00 GMT",
"version": "v2"
},
{
"created": "Fri, 18 May 2001 13:29:59 GMT",
"version": "v3"
}
] |
2014-11-17
|
[
[
"Leontaris",
"G. K.",
"",
"Univ. of Ioannina"
],
[
"Rizos",
"J.",
"",
"Univ. of Ioannina and\n CPHT"
]
] |
We explore the possibility of embedding the Pati-Salam model in the context of Type I brane models. We study a generic model with U(4)_C x U(2)_L x U(2)_R gauge symmetry and matter fields compatible with a Type I brane configuration. Examining the anomaly cancellation conditions of the surplus abelian symmetries we find an alternative hypercharge embedding that is compatible with a low string/brane scale of the order of 5-7 TeV, when the U(4)_C and U(2)_R brane stack couplings are equal. Proton stability is assured as baryon number is associated to a global symmetry remnant of the broken abelian factors. It is also shown that this scenario can accommodate an extra low energy abelian symmetry that can be associated to lepton number. The issue of fermion and especially neutrino masses is also discussed.
|
hep-ph/9507224
|
Kiselev
|
V.V.Kiselev
|
Modified renormalon
|
6 pages, LATEX file
| null | null |
IHEP 95-81, Protvino, Russia
|
hep-ph
| null |
In the framework of renormalon consideration in the approximation of a large
number of quark flavours, a role of the anomalous dependence of gluon
propagator on the scale $\mu$ is shown.
|
[
{
"created": "Wed, 5 Jul 1995 10:41:09 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Kiselev",
"V. V.",
""
]
] |
In the framework of renormalon consideration in the approximation of a large number of quark flavours, a role of the anomalous dependence of gluon propagator on the scale $\mu$ is shown.
|
2006.02617
|
Michael Strickland
|
Qianqian Du, Michael Strickland, Ubaid Tantary, Ben-Wei Zhang
|
Two-loop HTL-resummed thermodynamics for N=4 supersymmetric Yang-Mills
theory
|
38 pages, 7 figures
| null |
10.1007/JHEP09(2020)038
| null |
hep-ph hep-th nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We compute the two-loop hard-thermal-loop (HTL) resummed thermodynamic
potential for N=4 supersymmetric Yang-Mills (SYM). Our final result is
manifestly gauge-invariant and was renormalized using only simple vacuum
energy, gluon mass, scalar mass, and quark mass counter terms. The HTL mass
parameters m_D, M_D, and m_q are then determined self-consistently using a
variational prescription which results in a set of coupled gap equations. Based
on this, we obtain the two-loop HTL-resummed thermodynamic functions of N=4
SYM. We compare our final result with known results obtained in the weak- and
strong-coupling limits. We also compare to previously obtained approximately
self-consistent HTL resummations and Pad\'e approximants. We find that the
two-loop HTL resummed results for the scaled entropy density is a
quantitatively reliable approximation to the scaled entropy density for 0 <=
lambda <~ 2 and is in agreement with previous approximately self-consistent HTL
resummation results for lambda <~ 6.
|
[
{
"created": "Thu, 4 Jun 2020 02:27:18 GMT",
"version": "v1"
}
] |
2020-09-10
|
[
[
"Du",
"Qianqian",
""
],
[
"Strickland",
"Michael",
""
],
[
"Tantary",
"Ubaid",
""
],
[
"Zhang",
"Ben-Wei",
""
]
] |
We compute the two-loop hard-thermal-loop (HTL) resummed thermodynamic potential for N=4 supersymmetric Yang-Mills (SYM). Our final result is manifestly gauge-invariant and was renormalized using only simple vacuum energy, gluon mass, scalar mass, and quark mass counter terms. The HTL mass parameters m_D, M_D, and m_q are then determined self-consistently using a variational prescription which results in a set of coupled gap equations. Based on this, we obtain the two-loop HTL-resummed thermodynamic functions of N=4 SYM. We compare our final result with known results obtained in the weak- and strong-coupling limits. We also compare to previously obtained approximately self-consistent HTL resummations and Pad\'e approximants. We find that the two-loop HTL resummed results for the scaled entropy density is a quantitatively reliable approximation to the scaled entropy density for 0 <= lambda <~ 2 and is in agreement with previous approximately self-consistent HTL resummation results for lambda <~ 6.
|
1402.6678
|
Ibragim Alikhanov
|
I. Alikhanov
|
The Glashow resonance in neutrino-photon scattering
|
25 pages, 11 figures. Typos corrected, minor changes, new references
added. Accepted for publication in PLB
|
Phys.Lett.B741:295-300,2015
|
10.1016/j.physletb.2014.12.056
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Reactions ${\nu_l}\gamma\rightarrow W^+l^-\,(l=e,\mu,\tau)$ near the
threshold $\sqrt{s}=m_W+m_l$ are analyzed. Two independent calculations of the
corresponding cross sections (straightforward calculations using the Standard
Electroweak Lagrangian and calculations in the framework of the parton model)
are compared. It is shown that the Standard Electroweak Theory strongly
suggests that these reactions proceed via the Glashow resonances. Accordingly,
a hypothesis that the on-shell $W$ bosons in the reactions
${\nu_l}\gamma\rightarrow$$W^+l^-$ are the Glashow resonances is put forward. A
role of these reactions for testing T symmetry at the IceCube Neutrino
Observatory is discussed. A model with T-violating Glashow resonances for
description of the distribution of the TeV-PeV neutrino events recently
observed by the IceCube Collaboration is presented.
|
[
{
"created": "Wed, 26 Feb 2014 20:37:31 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Dec 2014 17:31:16 GMT",
"version": "v2"
}
] |
2015-01-16
|
[
[
"Alikhanov",
"I.",
""
]
] |
Reactions ${\nu_l}\gamma\rightarrow W^+l^-\,(l=e,\mu,\tau)$ near the threshold $\sqrt{s}=m_W+m_l$ are analyzed. Two independent calculations of the corresponding cross sections (straightforward calculations using the Standard Electroweak Lagrangian and calculations in the framework of the parton model) are compared. It is shown that the Standard Electroweak Theory strongly suggests that these reactions proceed via the Glashow resonances. Accordingly, a hypothesis that the on-shell $W$ bosons in the reactions ${\nu_l}\gamma\rightarrow$$W^+l^-$ are the Glashow resonances is put forward. A role of these reactions for testing T symmetry at the IceCube Neutrino Observatory is discussed. A model with T-violating Glashow resonances for description of the distribution of the TeV-PeV neutrino events recently observed by the IceCube Collaboration is presented.
|
hep-ph/9911363
|
G. Domokos and S. Kovesi-Domokos
|
G. Domokos and S. Kovesi-Domokos (Johns Hopkins University)
|
Energy Loss of Ultrahigh Energy Protons in Strong Magnetic Fields
|
11 pages, no figures, LaTeX2e
| null | null |
JHU-TIPAC-99009
|
hep-ph astro-ph
| null |
Ultrahigh energy protons in magnetic fields produce pions and thus lose
energy. The mean free path of such a process is worked out for Gaussian random
fields. Two cases are considered: an isotropic and a cylindrically symmetric
distribution. The energy loss is proportional to E^3 <B^2>; it becomes
significant for protons of energies larger than about 10^19 eV and magnetic
fields of about 10^9 Gauss. For energies and magnetic fields of this magnitude,
a proton injected into the magnetic field loses a substantial fraction of its
initial energy due to pion production.
|
[
{
"created": "Mon, 15 Nov 1999 17:36:14 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Domokos",
"G.",
"",
"Johns Hopkins University"
],
[
"Kovesi-Domokos",
"S.",
"",
"Johns Hopkins University"
]
] |
Ultrahigh energy protons in magnetic fields produce pions and thus lose energy. The mean free path of such a process is worked out for Gaussian random fields. Two cases are considered: an isotropic and a cylindrically symmetric distribution. The energy loss is proportional to E^3 <B^2>; it becomes significant for protons of energies larger than about 10^19 eV and magnetic fields of about 10^9 Gauss. For energies and magnetic fields of this magnitude, a proton injected into the magnetic field loses a substantial fraction of its initial energy due to pion production.
|
2203.03683
|
Xin-Nian Wang
|
Zhong Yang, Tan Luo, Wei Chen, Long-Gang Pang and Xin-Nian Wang
|
3D structure of jet-induced diffusion wake in an expanding quark-gluon
plasma
|
Final published version (with supplemental material)
| null |
10.1103/PhysRevLett.130.052301
| null |
hep-ph nucl-th
|
http://creativecommons.org/licenses/by/4.0/
|
The diffusion wake accompanying the jet-induced Mach cone provides a unique
probe of the properties of quark-gluon plasma in high-energy heavy-ion
collisions. It can be characterized by a depletion of soft hadrons in the
opposite direction of the propagating jet. We explore the 3D structure of the
diffusion wake induced by $\gamma$-triggered jets in Pb+Pb collisions at the
LHC energy within the coupled linear Boltzmann transport and hydro model. We
identify a valley structure caused by the diffusion wake on top of a ridge from
the initial multiple parton interaction (MPI) in jet-hadron correlation as a
function of rapidity and azimuthal angle. This leads to a double-peak structure
in the rapidity distribution of soft hadrons in the opposite direction of the
jets as an unambiguous signal of the diffusion wake. Using a two-Gaussian fit,
we extract the diffusion wake and MPI contributions to the double peak. The
diffusion wake valley is found to deepen with the jet energy loss as
characterized by the $\gamma$-jet asymmetry. Its sensitivity to the equation of
state and shear viscosity is also studied.
|
[
{
"created": "Mon, 7 Mar 2022 19:49:32 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Mar 2022 01:29:54 GMT",
"version": "v2"
},
{
"created": "Mon, 3 Oct 2022 18:52:22 GMT",
"version": "v3"
},
{
"created": "Thu, 26 Jan 2023 20:22:48 GMT",
"version": "v4"
}
] |
2023-02-15
|
[
[
"Yang",
"Zhong",
""
],
[
"Luo",
"Tan",
""
],
[
"Chen",
"Wei",
""
],
[
"Pang",
"Long-Gang",
""
],
[
"Wang",
"Xin-Nian",
""
]
] |
The diffusion wake accompanying the jet-induced Mach cone provides a unique probe of the properties of quark-gluon plasma in high-energy heavy-ion collisions. It can be characterized by a depletion of soft hadrons in the opposite direction of the propagating jet. We explore the 3D structure of the diffusion wake induced by $\gamma$-triggered jets in Pb+Pb collisions at the LHC energy within the coupled linear Boltzmann transport and hydro model. We identify a valley structure caused by the diffusion wake on top of a ridge from the initial multiple parton interaction (MPI) in jet-hadron correlation as a function of rapidity and azimuthal angle. This leads to a double-peak structure in the rapidity distribution of soft hadrons in the opposite direction of the jets as an unambiguous signal of the diffusion wake. Using a two-Gaussian fit, we extract the diffusion wake and MPI contributions to the double peak. The diffusion wake valley is found to deepen with the jet energy loss as characterized by the $\gamma$-jet asymmetry. Its sensitivity to the equation of state and shear viscosity is also studied.
|
1107.0130
|
Oliver Fochler
|
Oliver Fochler, Jan Uphoff, Zhe Xu and Carsten Greiner
|
Jet quenching and elliptic flow at RHIC and LHC within a pQCD-based
partonic transport model
|
To appear in the proceedings of Quark Matter 2011
| null |
10.1088/0954-3899/38/12/124152
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Fully dynamic simulations of heavy ion collisions at RHIC and at LHC energies
within the perturbative QCD-based partonic transport model BAMPS (Boltzmann
Approach to Multi-Parton Scatterings) are presented, focusing on the
simultaneous investigation of jet quenching and elliptic flow. The model
features inelastic 2 <-> 3 processes based on the Gunion-Bertsch matrix element
and has recently been extended to include light quark degrees of freedom,
allowing for direct comparison to hadronic data on the nuclear modification
factor via a fragmentation scheme for high-pT partons. The nuclear modification
factor of neutral pions in central Au+Au collisions at RHIC energy is compared
to experimental data. Furthermore first results on the nuclear modification
factor and the integrated elliptic flow of charged hadrons in Pb+Pb collisions
at LHC are presented and compared to recent ALICE data. These investigations
are complemented by a study on the suppression of D-mesons at LHC based on
elastic interactions with the medium.
|
[
{
"created": "Fri, 1 Jul 2011 07:49:39 GMT",
"version": "v1"
}
] |
2015-05-28
|
[
[
"Fochler",
"Oliver",
""
],
[
"Uphoff",
"Jan",
""
],
[
"Xu",
"Zhe",
""
],
[
"Greiner",
"Carsten",
""
]
] |
Fully dynamic simulations of heavy ion collisions at RHIC and at LHC energies within the perturbative QCD-based partonic transport model BAMPS (Boltzmann Approach to Multi-Parton Scatterings) are presented, focusing on the simultaneous investigation of jet quenching and elliptic flow. The model features inelastic 2 <-> 3 processes based on the Gunion-Bertsch matrix element and has recently been extended to include light quark degrees of freedom, allowing for direct comparison to hadronic data on the nuclear modification factor via a fragmentation scheme for high-pT partons. The nuclear modification factor of neutral pions in central Au+Au collisions at RHIC energy is compared to experimental data. Furthermore first results on the nuclear modification factor and the integrated elliptic flow of charged hadrons in Pb+Pb collisions at LHC are presented and compared to recent ALICE data. These investigations are complemented by a study on the suppression of D-mesons at LHC based on elastic interactions with the medium.
|
2303.02692
|
Wei Tao
|
Wei Tao, Zhen-Jun Xiao, Ruilin Zhu
|
Convergent decay constants for beauty-charm mesons at N$^3$LO in QCD and
phenomenological implications
|
The content of this paper arXiv:2303.02692 substantially overlaps
with that of the paper arXiv:2303.07220, the latter of which has already been
published in the JHEP journal (JHEP 05 (2023) 189)
| null | null | null |
hep-ph
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
We show the three-loop calculation of the matching coefficients
$\mathcal{C}_J$ for the four heavy flavor-changing currents in nonrelativistic
Quantum Chromodynamics effective theory and confirm the surprising observation
of the nonconvergence behaviors of the matching coefficients for beauty-charm
mesons. We demonstrate that the higher-order correction to the wave function at
origin can solve the nonconvergence problem. By employing the scaling relation,
we simultaneously obtain the decay constants for beauty-charm mesons up to the
three-loop accuracy and the hyperfine mass splitting in agreement with the
experimental data. The perturbative predictions for the leptonic decays of the
beauty-charm mesons shall provide a guide in ongoing and future precision heavy
flavor experiments.
|
[
{
"created": "Sun, 5 Mar 2023 15:11:31 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Oct 2023 01:50:06 GMT",
"version": "v2"
}
] |
2023-10-19
|
[
[
"Tao",
"Wei",
""
],
[
"Xiao",
"Zhen-Jun",
""
],
[
"Zhu",
"Ruilin",
""
]
] |
We show the three-loop calculation of the matching coefficients $\mathcal{C}_J$ for the four heavy flavor-changing currents in nonrelativistic Quantum Chromodynamics effective theory and confirm the surprising observation of the nonconvergence behaviors of the matching coefficients for beauty-charm mesons. We demonstrate that the higher-order correction to the wave function at origin can solve the nonconvergence problem. By employing the scaling relation, we simultaneously obtain the decay constants for beauty-charm mesons up to the three-loop accuracy and the hyperfine mass splitting in agreement with the experimental data. The perturbative predictions for the leptonic decays of the beauty-charm mesons shall provide a guide in ongoing and future precision heavy flavor experiments.
|
hep-ph/9707488
|
Johannes Bluemlein
|
J. Bl\"umlein and A. Vogt
|
The Resummed Gluon Anomalous Dimension and Structure Functions at Small
x
|
8 pages latex, including 2 eps figures
|
Phys.Rev.D57:1-5,1998
|
10.1103/PhysRevD.57.1
|
DESY 97-143, WUE-ITP-97-022
|
hep-ph
| null |
The impact of the resummed next-to-leading logarithmic small-$x$
contributions to the anomalous dimension $\gamma_{gg}$ is evaluated for the
unpolarized parton densities and structure functions of the nucleon. These new
terms diminish the gluon distribution and overcompensate the contribution
caused by the resummed leading logarithmic small-$x$ anomalous dimension and
the quarkonic anomalous dimensions beyond next-to-leading order.
|
[
{
"created": "Sun, 27 Jul 1997 22:38:35 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Mar 1998 14:08:48 GMT",
"version": "v2"
}
] |
2016-09-06
|
[
[
"Blümlein",
"J.",
""
],
[
"Vogt",
"A.",
""
]
] |
The impact of the resummed next-to-leading logarithmic small-$x$ contributions to the anomalous dimension $\gamma_{gg}$ is evaluated for the unpolarized parton densities and structure functions of the nucleon. These new terms diminish the gluon distribution and overcompensate the contribution caused by the resummed leading logarithmic small-$x$ anomalous dimension and the quarkonic anomalous dimensions beyond next-to-leading order.
|
1609.00371
|
Jae-hyeon Park
|
Peter Athron, Jae-hyeon Park, Tom Steudtner, Dominik St\"ockinger,
Alexander Voigt
|
Precise Higgs mass calculations in (non-)minimal supersymmetry at both
high and low scales
|
51 pages, corrected eq. (27), made minor corrections to some plots
and text
|
JHEP 1701 (2017) 079
|
10.1007/JHEP01(2017)079
|
CoEPP-MN-16-20, DESY 16-057, KIAS-Q16008
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We present FlexibleEFTHiggs, a method for calculating the SM-like Higgs pole
mass in SUSY (and even non-SUSY) models, which combines an effective field
theory approach with a diagrammatic calculation. It thus achieves an all order
resummation of leading logarithms together with the inclusion of all
non-logarithmic 1-loop contributions. We implement this method into
FlexibleSUSY and study its properties in the MSSM, NMSSM, E6SSM and MRSSM. In
the MSSM, it correctly interpolates between the known results of effective
field theory calculations in the literature for a high SUSY scale and
fixed-order calculations in the full theory for a sub-TeV SUSY scale. We
compare our MSSM results to those from public codes and identify the origin of
the most significant deviations between the DR-bar programs. We then perform a
similar comparison in the remaining three non-minimal models. For all four
models we estimate the theoretical uncertainty of FlexibleEFTHiggs and the
fixed-order DR-bar programs thereby finding that the former becomes more
precise than the latter for a SUSY scale above a few TeV. Even for sub-TeV SUSY
scales, FlexibleEFTHiggs maintains the uncertainty estimate around 2-3 GeV,
remaining a competitive alternative to existing fixed-order computations.
|
[
{
"created": "Thu, 1 Sep 2016 19:59:59 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Sep 2016 11:25:46 GMT",
"version": "v2"
},
{
"created": "Fri, 6 Jan 2017 16:57:29 GMT",
"version": "v3"
}
] |
2017-01-23
|
[
[
"Athron",
"Peter",
""
],
[
"Park",
"Jae-hyeon",
""
],
[
"Steudtner",
"Tom",
""
],
[
"Stöckinger",
"Dominik",
""
],
[
"Voigt",
"Alexander",
""
]
] |
We present FlexibleEFTHiggs, a method for calculating the SM-like Higgs pole mass in SUSY (and even non-SUSY) models, which combines an effective field theory approach with a diagrammatic calculation. It thus achieves an all order resummation of leading logarithms together with the inclusion of all non-logarithmic 1-loop contributions. We implement this method into FlexibleSUSY and study its properties in the MSSM, NMSSM, E6SSM and MRSSM. In the MSSM, it correctly interpolates between the known results of effective field theory calculations in the literature for a high SUSY scale and fixed-order calculations in the full theory for a sub-TeV SUSY scale. We compare our MSSM results to those from public codes and identify the origin of the most significant deviations between the DR-bar programs. We then perform a similar comparison in the remaining three non-minimal models. For all four models we estimate the theoretical uncertainty of FlexibleEFTHiggs and the fixed-order DR-bar programs thereby finding that the former becomes more precise than the latter for a SUSY scale above a few TeV. Even for sub-TeV SUSY scales, FlexibleEFTHiggs maintains the uncertainty estimate around 2-3 GeV, remaining a competitive alternative to existing fixed-order computations.
|
1810.00264
|
Marco Guzzi
|
Marco Guzzi, Tie-Jiun Hou, Sayipjamal Dulat, Jun Gao, Joey Huston,
Pavel Nadolsky, Carl Schmidt, Jan Winter, Keping Xie, C.-P. Yuan
|
CTEQ-TEA parton distribution functions with intrinsic charm
|
7 pages, 2 figures. Conference Proceedings of CIPANP2018, 13th
Conference on the Intersections of Particle and Nuclear Physics, May 29 -
June 3, 2018 Palm Springs, CA. Based on arXiv: 1707.00657, published in JHEP
1802 (2018) 059
| null |
10.1051/epjconf/201819200003
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The possibility of a (sizable) nonperturbative contribution to the charm
parton distribution function (PDF) in a nucleon is investigated together with
theoretical issues arising in its interpretation. Results from the global PDF
analysis are presented. The separation of the universal component of the
nonperturbative charm from the rest of the radiative contributions is discussed
and the potential impact of a nonperturbative charm PDF on LHC scattering
processes is illustrated. An estimate of nonperturbative charm magnitude in the
CT14 and CT14HERA2 global QCD analyses at the next-to-next-to leading order
(NNLO) in the QCD coupling strength is given by including the latest
experimental data from HERA and the Large Hadron Collider (LHC). A comparison
between different models of intrinsic charm is shown and prospects for standard
candle observables at the LHC are illustrated.
|
[
{
"created": "Sat, 29 Sep 2018 20:54:24 GMT",
"version": "v1"
}
] |
2018-12-05
|
[
[
"Guzzi",
"Marco",
""
],
[
"Hou",
"Tie-Jiun",
""
],
[
"Dulat",
"Sayipjamal",
""
],
[
"Gao",
"Jun",
""
],
[
"Huston",
"Joey",
""
],
[
"Nadolsky",
"Pavel",
""
],
[
"Schmidt",
"Carl",
""
],
[
"Winter",
"Jan",
""
],
[
"Xie",
"Keping",
""
],
[
"Yuan",
"C. -P.",
""
]
] |
The possibility of a (sizable) nonperturbative contribution to the charm parton distribution function (PDF) in a nucleon is investigated together with theoretical issues arising in its interpretation. Results from the global PDF analysis are presented. The separation of the universal component of the nonperturbative charm from the rest of the radiative contributions is discussed and the potential impact of a nonperturbative charm PDF on LHC scattering processes is illustrated. An estimate of nonperturbative charm magnitude in the CT14 and CT14HERA2 global QCD analyses at the next-to-next-to leading order (NNLO) in the QCD coupling strength is given by including the latest experimental data from HERA and the Large Hadron Collider (LHC). A comparison between different models of intrinsic charm is shown and prospects for standard candle observables at the LHC are illustrated.
|
hep-ph/0308291
|
Atsushi Nakamura
|
Teiji Kunihiro, Shin Muroya, Atushi Nakamura, Chiho Nonaka, Motoo
Sekiguchi and Hiroaki Wada
|
Scalar Particles in Lattice QCD
|
4 figures, to be published in Proceedings of `International Symposium
on Hadron Spectroscopy, Chiral Symmetry and Relativistic Description of Bound
Systems' (in a series of KEK proceedings)
| null |
10.1103/PhysRevD.70.034504
| null |
hep-ph
| null |
We report a project to study scalar particles by lattice QCD simulations.
After a brief introduction of the current situation of lattice study of the
sigma meson, we describe our numerical simulations of scalar mesons, $\sigma$
and $\kappa$. We observe a low sigma mass, $m_\pi<m_\sigma\le m_\rho$, for
which the disconnected diagram plays an important role. For the kappa meson, we
obtain higher mass than the experimental value, i.e., $m_\kappa\sim 2m_{K^*}$.
|
[
{
"created": "Thu, 28 Aug 2003 09:44:39 GMT",
"version": "v1"
}
] |
2009-11-10
|
[
[
"Kunihiro",
"Teiji",
""
],
[
"Muroya",
"Shin",
""
],
[
"Nakamura",
"Atushi",
""
],
[
"Nonaka",
"Chiho",
""
],
[
"Sekiguchi",
"Motoo",
""
],
[
"Wada",
"Hiroaki",
""
]
] |
We report a project to study scalar particles by lattice QCD simulations. After a brief introduction of the current situation of lattice study of the sigma meson, we describe our numerical simulations of scalar mesons, $\sigma$ and $\kappa$. We observe a low sigma mass, $m_\pi<m_\sigma\le m_\rho$, for which the disconnected diagram plays an important role. For the kappa meson, we obtain higher mass than the experimental value, i.e., $m_\kappa\sim 2m_{K^*}$.
|
0908.4168
|
Chia-Min Lin
|
Chia-Min Lin
|
Large non-Gaussianity generated at the end of Extended D-term Hybrid
Inflation
|
8 pages
| null | null | null |
hep-ph astro-ph.HE hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this paper, we show that if we extend D-term hybrid inflation by adding a
light scalar field which couples to a waterfall field, large non-Gaussianity
can be generated at the end of inflation. Contribution of cosmic strings
generated after D-term inflation to the Cosmic Microwave Background (CMB)
angular power spectrum can be as low as 10% and this also evade the spectral
index problem.
|
[
{
"created": "Fri, 28 Aug 2009 09:38:05 GMT",
"version": "v1"
}
] |
2009-08-31
|
[
[
"Lin",
"Chia-Min",
""
]
] |
In this paper, we show that if we extend D-term hybrid inflation by adding a light scalar field which couples to a waterfall field, large non-Gaussianity can be generated at the end of inflation. Contribution of cosmic strings generated after D-term inflation to the Cosmic Microwave Background (CMB) angular power spectrum can be as low as 10% and this also evade the spectral index problem.
|
2003.01686
|
Neda Sadooghi
|
S. M. A. Tabatabaee and N. Sadooghi
|
Wigner function formalism and the evolution of thermodynamic quantities
in an expanding magnetized plasma
|
23 pages, 9 figures
|
Phys. Rev. D 101, 076022 (2020)
|
10.1103/PhysRevD.101.076022
| null |
hep-ph hep-th nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
By combining the Wigner function formalism of relativistic quantum kinetic
theory with fundamental equations of relativistic magnetohydrodynamics (MHD),
we present a novel approach to determine the proper time evolution of the
temperature and other thermodynamic quantities in a uniformly expanding hot,
magnetized, and weakly interacting plasma. The aim is to study the contribution
of quantum corrections to this evolution. We first determine the corresponding
Wigner function in terms of the solution of the Dirac equation in the presence
of a constant magnetic field. Using this function, we then compute the
energy-momentum tensor of the above-mentioned plasma, which eventually yields
its energy density and pressure. Plugging these quantities in the energy
equation of relativistic MHD, we arrive, after choosing an appropriate
coordinate system, at a differential equation for the temperature as a function
of the proper time. The numerical solution of this equation leads finally to
the proper time evolution of the temperature. The latter is then used to
determine the evolution of a large number of thermodynamic quantities in this
expanding and magnetized plasma. We compare our results with other existing
results from relativistic MHD. We also comment on the effect of point to point
decaying magnetic fields on the thermodynamic properties of this plasma.
|
[
{
"created": "Tue, 3 Mar 2020 18:11:20 GMT",
"version": "v1"
}
] |
2020-05-06
|
[
[
"Tabatabaee",
"S. M. A.",
""
],
[
"Sadooghi",
"N.",
""
]
] |
By combining the Wigner function formalism of relativistic quantum kinetic theory with fundamental equations of relativistic magnetohydrodynamics (MHD), we present a novel approach to determine the proper time evolution of the temperature and other thermodynamic quantities in a uniformly expanding hot, magnetized, and weakly interacting plasma. The aim is to study the contribution of quantum corrections to this evolution. We first determine the corresponding Wigner function in terms of the solution of the Dirac equation in the presence of a constant magnetic field. Using this function, we then compute the energy-momentum tensor of the above-mentioned plasma, which eventually yields its energy density and pressure. Plugging these quantities in the energy equation of relativistic MHD, we arrive, after choosing an appropriate coordinate system, at a differential equation for the temperature as a function of the proper time. The numerical solution of this equation leads finally to the proper time evolution of the temperature. The latter is then used to determine the evolution of a large number of thermodynamic quantities in this expanding and magnetized plasma. We compare our results with other existing results from relativistic MHD. We also comment on the effect of point to point decaying magnetic fields on the thermodynamic properties of this plasma.
|
hep-ph/9905291
|
Volodya Miransky
|
F. A. Chishtie, V. Elias, V. A. Miransky, T. G. Steele
|
Pade-Summation Approach to QCD Beta-Function Infrared Properties
|
20 postscript figures now embedded in latex2e. Minor changes to text
|
Prog.Theor.Phys.104:603-631,2000
|
10.1143/PTP.104.603
| null |
hep-ph hep-th
| null |
We address whether Pad\'e-summations of the $\bar{MS}$ QCD $\beta$-function
for a given number of flavours exhibit an infrared-stable fixed point, or
alternatively, an infrared attractor of a double valued couplant as noted by
Kogan and Shifman for the case of supersymmetric gluodynamics. Below an
approximant-dependent flavour threshold $(6 \leq n_f \leq 8)$, we find that
Pad\'e-summation $\beta$-functions incorporating $[2|1], [1|2], [2|2], [1|3]$,
and $[3|1]$ approximants always exhibit a positive pole prior to the occurrence
of their first positive zero, precluding any identification of this first
positive zero as an infrared-stable fixed point of the $\beta$- function. This
result is shown to be true regardless of the magnitude of the presently-unknown
five-loop $\beta$-function contribution. Moreover, the pole in question
suggests the occurrence of dynamics in which both a strong and an
asymptotically-free phase share a common infrared attractor. We briefly discuss
the possible relevance of infrared-attractor dynamics to the success of recent
calculations of the glueball mass spectra in QCD with $N_c \to \infty$ via
supergravity. As $n_f$ increases above an approximant-dependent flavour
threshold, Pad\'e-summation $\beta$-functions incorporating $[2|2], [1|3]$, and
$[3|1]$ approximants exhibit dynamics controlled by an infrared-stable fixed
point over a widening domain of the five-loop $\bar{MS}$ $\beta$-function
parameter $(\beta_4/\beta_0)$. Above this threshold, all approximants
considered exhibit infrared-stable fixed points that decrease in magnitude with
increasing flavour number.
|
[
{
"created": "Mon, 10 May 1999 18:48:40 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Sep 1999 17:44:55 GMT",
"version": "v2"
},
{
"created": "Thu, 29 Jun 2000 20:43:04 GMT",
"version": "v3"
}
] |
2009-09-25
|
[
[
"Chishtie",
"F. A.",
""
],
[
"Elias",
"V.",
""
],
[
"Miransky",
"V. A.",
""
],
[
"Steele",
"T. G.",
""
]
] |
We address whether Pad\'e-summations of the $\bar{MS}$ QCD $\beta$-function for a given number of flavours exhibit an infrared-stable fixed point, or alternatively, an infrared attractor of a double valued couplant as noted by Kogan and Shifman for the case of supersymmetric gluodynamics. Below an approximant-dependent flavour threshold $(6 \leq n_f \leq 8)$, we find that Pad\'e-summation $\beta$-functions incorporating $[2|1], [1|2], [2|2], [1|3]$, and $[3|1]$ approximants always exhibit a positive pole prior to the occurrence of their first positive zero, precluding any identification of this first positive zero as an infrared-stable fixed point of the $\beta$- function. This result is shown to be true regardless of the magnitude of the presently-unknown five-loop $\beta$-function contribution. Moreover, the pole in question suggests the occurrence of dynamics in which both a strong and an asymptotically-free phase share a common infrared attractor. We briefly discuss the possible relevance of infrared-attractor dynamics to the success of recent calculations of the glueball mass spectra in QCD with $N_c \to \infty$ via supergravity. As $n_f$ increases above an approximant-dependent flavour threshold, Pad\'e-summation $\beta$-functions incorporating $[2|2], [1|3]$, and $[3|1]$ approximants exhibit dynamics controlled by an infrared-stable fixed point over a widening domain of the five-loop $\bar{MS}$ $\beta$-function parameter $(\beta_4/\beta_0)$. Above this threshold, all approximants considered exhibit infrared-stable fixed points that decrease in magnitude with increasing flavour number.
|
1506.02657
|
Michael Gustafsson Dr
|
Cha\"imae El Aisati, Michael Gustafsson and Thomas Hambye
|
New Search for Monochromatic Neutrinos from Dark Matter Decay
|
12 pages, 13 figures. Tabulated results attached among the source
files (Appendix_D_Table.dat)
|
Phys. Rev. D 92, 123515 (2015)
|
10.1103/PhysRevD.92.123515
|
ULB-TH/15-06
|
hep-ph astro-ph.HE
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
From data recently reported from the IceCube telescope, we derive new bounds
on the monochromatic neutrino signal produced from dark matter particle decays.
In the few TeV to tens of TeV energy range, these bounds turn out to be better
than previous limits by more than an order of magnitude. As a result, intensity
constraints on neutrino lines at energies above a few TeV are now comparable to
those on gamma-ray lines. From the same data sample, we also perform a detailed
search for a neutrino line, showing that there is no significant hint for such
a signal.
|
[
{
"created": "Mon, 8 Jun 2015 20:00:29 GMT",
"version": "v1"
}
] |
2015-12-23
|
[
[
"Aisati",
"Chaïmae El",
""
],
[
"Gustafsson",
"Michael",
""
],
[
"Hambye",
"Thomas",
""
]
] |
From data recently reported from the IceCube telescope, we derive new bounds on the monochromatic neutrino signal produced from dark matter particle decays. In the few TeV to tens of TeV energy range, these bounds turn out to be better than previous limits by more than an order of magnitude. As a result, intensity constraints on neutrino lines at energies above a few TeV are now comparable to those on gamma-ray lines. From the same data sample, we also perform a detailed search for a neutrino line, showing that there is no significant hint for such a signal.
|
1207.4584
|
Durmus Demir
|
D. A. Demir
|
Gravi-Natural Higgs and Conformal New Physics
|
27 pages
| null | null |
IZTECH-P/2012-02
|
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study gauge hierarchy problem of the Standard Model (SM) not by
introducing new physics at the electroweak scale but by utilizing gravitational
frames, frames generated by conformal transformations, as a renormalization
medium. The essence of the naturalization mechanism is that a particular
conformal transformation with respect to the Higgs field completely decouples
Higgs from matter fields so that the terms causing quadratic divergences become
genuine benign. In this frame, we analyze stability, unitarity and
renormalizability of the interactions, and construct the effective $SM$ theory
at the electroweak scale by taking into account the conformal anomalies. We
scrutinize certain salient features of the framework, and discuss h -> gamma
gamma decay as an application.
The proposed mechanism naturalizes not only the SM but also its extensions if
they involve no new mass scales and exhibit strict conformal invariance. The
new physics thus forms a conformal field theory (CFT), and can involve
additional fermion generations, extra gauge groups as well as all kinds of SM
singlets. Certain phenomena, for instance, CP-violating Higgs sector, Dark
Matter and Inflation, can be modeled with less free parameters. Scalar and
vector singlets can directly interact with the SM spectrum, and can be searched
for in certain scattering processes such as the invisible decays of the Higgs
boson.
|
[
{
"created": "Thu, 19 Jul 2012 08:58:48 GMT",
"version": "v1"
}
] |
2012-07-20
|
[
[
"Demir",
"D. A.",
""
]
] |
We study gauge hierarchy problem of the Standard Model (SM) not by introducing new physics at the electroweak scale but by utilizing gravitational frames, frames generated by conformal transformations, as a renormalization medium. The essence of the naturalization mechanism is that a particular conformal transformation with respect to the Higgs field completely decouples Higgs from matter fields so that the terms causing quadratic divergences become genuine benign. In this frame, we analyze stability, unitarity and renormalizability of the interactions, and construct the effective $SM$ theory at the electroweak scale by taking into account the conformal anomalies. We scrutinize certain salient features of the framework, and discuss h -> gamma gamma decay as an application. The proposed mechanism naturalizes not only the SM but also its extensions if they involve no new mass scales and exhibit strict conformal invariance. The new physics thus forms a conformal field theory (CFT), and can involve additional fermion generations, extra gauge groups as well as all kinds of SM singlets. Certain phenomena, for instance, CP-violating Higgs sector, Dark Matter and Inflation, can be modeled with less free parameters. Scalar and vector singlets can directly interact with the SM spectrum, and can be searched for in certain scattering processes such as the invisible decays of the Higgs boson.
|
0705.3841
|
Michael Andreas Schmidt
|
Michael Andreas Schmidt
|
Renormalization Group Evolution in the type I + II seesaw model
|
14 pages, 5 figures; v4: added contribution from missing box diagram
with charged leptons to Eqs. (14f,14g) and corrected sign mistakes in (14h).
This led to corrections to Eqs. (17,18,B5d,B5e) and third row of Tab. II
|
Phys.Rev.D76:073010,2007
|
10.1103/PhysRevD.76.073010
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We carefully analyze the renormalization group equations in the type I + II
seesaw scenario in the extended standard model (SM) and minimal supersymmetric
standard model (MSSM). Furthermore, we present analytic formulae of the mixing
angles and phases and discuss the RG effect on the different mixing parameters
in the type II seesaw scenario. The renormalization group equations of the
angles have a contribution which is proportional to the mass squared difference
for a hierarchical spectrum. This is in contrast to the inverse proportionality
to the mass squared difference in the effective field theory case.
|
[
{
"created": "Fri, 25 May 2007 20:07:41 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Oct 2007 16:02:57 GMT",
"version": "v2"
},
{
"created": "Mon, 9 Apr 2012 01:46:11 GMT",
"version": "v3"
},
{
"created": "Sat, 28 May 2022 04:02:13 GMT",
"version": "v4"
}
] |
2022-05-31
|
[
[
"Schmidt",
"Michael Andreas",
""
]
] |
We carefully analyze the renormalization group equations in the type I + II seesaw scenario in the extended standard model (SM) and minimal supersymmetric standard model (MSSM). Furthermore, we present analytic formulae of the mixing angles and phases and discuss the RG effect on the different mixing parameters in the type II seesaw scenario. The renormalization group equations of the angles have a contribution which is proportional to the mass squared difference for a hierarchical spectrum. This is in contrast to the inverse proportionality to the mass squared difference in the effective field theory case.
|
hep-ph/9407370
|
Jim Ohnemus
|
J. Ohnemus
|
Hadronic $Z\gamma$ Production with QCD Corrections and Leptonic Decays
|
16 pages + 9 figures, UCD-94-29. A postscript version and 9
postscript figures are available via anonymous ftp to UCDHEP.UCDAVIS.EDU in
the directory [.ohnemus.ucd-94-29]
|
Phys.Rev. D51 (1995) 1068-1076
|
10.1103/PhysRevD.51.1068
| null |
hep-ph
| null |
The process $p p \to Z \gamma + X \to \ell^- \ell^+ \gamma + X$, where $\ell$
denotes a lepton, is calculated to order $\alpha_s$. Total and differential
cross sections, with acceptance cuts imposed on the leptons and photon, are
given for the Tevatron and LHC center of mass energies. In general, invariant
mass and angular distributions are simply scaled up in magnitude by the QCD
radiative corrections, whereas in transverse momentum distributions, the QCD
radiative corrections increase with the transverse momentum.
|
[
{
"created": "Tue, 26 Jul 1994 01:41:01 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Ohnemus",
"J.",
""
]
] |
The process $p p \to Z \gamma + X \to \ell^- \ell^+ \gamma + X$, where $\ell$ denotes a lepton, is calculated to order $\alpha_s$. Total and differential cross sections, with acceptance cuts imposed on the leptons and photon, are given for the Tevatron and LHC center of mass energies. In general, invariant mass and angular distributions are simply scaled up in magnitude by the QCD radiative corrections, whereas in transverse momentum distributions, the QCD radiative corrections increase with the transverse momentum.
|
1509.00218
|
Arunansu Sil
|
Abhijit Kumar Saha and Arunansu Sil
|
A Dynamic Modification to Sneutrino Chaotic Inflation
|
24 pages, 3 figures; version to appear in JHEP
| null |
10.1007/JHEP11(2015)118
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider a right-handed scalar neutrino as the inflaton which carries a
gravitational coupling with a supersymmetric QCD sector responsible for
breaking supersymmetry dynamically. The framework suggests an inflaton
potential which is a deformed version of the quadratic chaotic inflation
leading to a flatter potential. We find that this deformation results a sizable
tensor to scalar ratio which falls within the allowed region by PLANCK 2015. At
the same time supersymmetry breaking at the end of inflation can naturally be
induced in this set-up. The symmetries required to construct the framework
allows the neutrino masses and mixing to be of right order.
|
[
{
"created": "Tue, 1 Sep 2015 10:50:42 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Nov 2015 10:41:06 GMT",
"version": "v2"
}
] |
2016-01-20
|
[
[
"Saha",
"Abhijit Kumar",
""
],
[
"Sil",
"Arunansu",
""
]
] |
We consider a right-handed scalar neutrino as the inflaton which carries a gravitational coupling with a supersymmetric QCD sector responsible for breaking supersymmetry dynamically. The framework suggests an inflaton potential which is a deformed version of the quadratic chaotic inflation leading to a flatter potential. We find that this deformation results a sizable tensor to scalar ratio which falls within the allowed region by PLANCK 2015. At the same time supersymmetry breaking at the end of inflation can naturally be induced in this set-up. The symmetries required to construct the framework allows the neutrino masses and mixing to be of right order.
|
hep-ph/0302233
|
Lance Dixon
|
Lance Dixon and M. Stewart Siu
|
Resonance-continuum interference in the di-photon Higgs signal at the
LHC
|
10 pages, 2 figures
|
Phys.Rev.Lett.90:252001,2003
|
10.1103/PhysRevLett.90.252001
|
SLAC-PUB-9654
|
hep-ph hep-ex
| null |
A low mass Standard Model Higgs boson should be visible at the Large Hadron
Collider through its production via gluon-gluon fusion and its decay to two
photons. We compute the interference of this resonant process, gg -> H -> gamma
gamma, with the continuum QCD background, gg -> gamma gamma induced by quark
loops. Helicity selection rules suppress the effect, which is dominantly due to
the imaginary part of the two-loop gg -> gamma gamma scattering amplitude. The
interference is destructive, but only of order 5% in the Standard Model, which
is still below the 10-20% present accuracy of the total cross section
prediction. We comment on the potential size of such effects in other Higgs
models.
|
[
{
"created": "Tue, 25 Feb 2003 20:18:36 GMT",
"version": "v1"
}
] |
2010-11-15
|
[
[
"Dixon",
"Lance",
""
],
[
"Siu",
"M. Stewart",
""
]
] |
A low mass Standard Model Higgs boson should be visible at the Large Hadron Collider through its production via gluon-gluon fusion and its decay to two photons. We compute the interference of this resonant process, gg -> H -> gamma gamma, with the continuum QCD background, gg -> gamma gamma induced by quark loops. Helicity selection rules suppress the effect, which is dominantly due to the imaginary part of the two-loop gg -> gamma gamma scattering amplitude. The interference is destructive, but only of order 5% in the Standard Model, which is still below the 10-20% present accuracy of the total cross section prediction. We comment on the potential size of such effects in other Higgs models.
|
hep-ph/9905562
|
Kolya Nikolaev
|
N.N. Nikolaev (Institut f. Kernphysik, Forschungszentrum J\"ulich,
J\"ulich, Germany & L.D.Landau Institute for Theoretical Physics,
Chernogolovka, Russia)
|
Intrinsic $k_{\perp}$ in the pomeron
|
5 pages, to appear in Proceedings of Workshop on Monte Carlo at HERA,
DESY. Extended discussion of QCD mechanism of Diffractive DIS added in the
Introduction
| null | null | null |
hep-ph
| null |
In a consistent QCD approach to diffractive DIS gluons in the pomeron have
soft $z_{g}$ distribution and very broad intrinsic $k_{\perp}$ distribution.
The latter has not yet been incorporated into diffractive Monte-Carlo
generators (RAPGAP,....). I argue that the so-introduced bias in the
diffractive jet analysis may be the reason why H1 Collaboration finds the very
large and hard gluon content of the pomeron. I discuss possible direct
experimental determinations of intrinsic $k_{\perp}$ in the pomeron.
|
[
{
"created": "Mon, 31 May 1999 11:39:16 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Aug 1999 16:03:08 GMT",
"version": "v2"
}
] |
2007-05-23
|
[
[
"Nikolaev",
"N. N.",
"",
"Institut f. Kernphysik, Forschungszentrum Jülich,\n Jülich, Germany & L.D.Landau Institute for Theoretical Physics,\n Chernogolovka, Russia"
]
] |
In a consistent QCD approach to diffractive DIS gluons in the pomeron have soft $z_{g}$ distribution and very broad intrinsic $k_{\perp}$ distribution. The latter has not yet been incorporated into diffractive Monte-Carlo generators (RAPGAP,....). I argue that the so-introduced bias in the diffractive jet analysis may be the reason why H1 Collaboration finds the very large and hard gluon content of the pomeron. I discuss possible direct experimental determinations of intrinsic $k_{\perp}$ in the pomeron.
|
hep-ph/0408280
|
Bernd Kniehl
|
M. Klasen, B.A. Kniehl, L.N. Mihaila, M. Steinhauser
|
J/psi plus prompt-photon associated production in two-photon collisions
at next-to-leading order
|
31 pages, 9 figures
|
Phys.Rev.D71:014016,2005
|
10.1103/PhysRevD.71.014016
|
DESY 04-149, LPSC 04-040
|
hep-ph
| null |
We calculate the cross section of J/psi plus prompt-photon inclusive
production in gamma gamma collisions at next-to-leading order within the
factorization formalism of nonrelativistic quantum chromodynamics (NRQCD)
focusing on direct photoproduction. Apart from direct J/psi production, we also
include the feed-down from directly-produced chi_{cJ} and psi' mesons. We
discuss the analytical calculation, in particular the treatment of the various
types of singularities and the NRQCD operator renormalization, in some detail.
We present theoretical predictions for the future e^+e^- linear collider TESLA,
taking into account both brems- and beamstrahlung.
|
[
{
"created": "Wed, 25 Aug 2004 13:44:20 GMT",
"version": "v1"
}
] |
2011-03-23
|
[
[
"Klasen",
"M.",
""
],
[
"Kniehl",
"B. A.",
""
],
[
"Mihaila",
"L. N.",
""
],
[
"Steinhauser",
"M.",
""
]
] |
We calculate the cross section of J/psi plus prompt-photon inclusive production in gamma gamma collisions at next-to-leading order within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD) focusing on direct photoproduction. Apart from direct J/psi production, we also include the feed-down from directly-produced chi_{cJ} and psi' mesons. We discuss the analytical calculation, in particular the treatment of the various types of singularities and the NRQCD operator renormalization, in some detail. We present theoretical predictions for the future e^+e^- linear collider TESLA, taking into account both brems- and beamstrahlung.
|
hep-ph/9911520
|
H. Sazdjian
|
H. Sazdjian (Univ. of Orsay, France)
|
Pionium lifetime and \pi\pi scattering lengths in generalized chiral
perurbation theory
|
4 pages, 1 figure (included in the text), Latex. Uses espcrc2.sty.
Talk given at the QCD99 Conference, Montpellier, 7-13 July 1999. To appear in
the Proceedings
|
Nucl.Phys.Proc.Suppl. 86 (2000) 271-274
|
10.1016/S0920-5632(00)00575-2
| null |
hep-ph
| null |
The relationship between the pionium lifetime and the $\pi\pi$ scattering
lengths is established, including the sizable electromagnetic corrections. The
bound state formalism that is used is that of constraint theory which provides
a covariant three-dimensional reduction of the Bethe--Salpeter equation. The
framework of generalized chiral perturbation theory allows then an analysis of
the lifetime value as a function of the $\pi\pi$ scattering lengths, the latter
being dependent on the quark condensate value.
|
[
{
"created": "Mon, 29 Nov 1999 15:28:30 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Sazdjian",
"H.",
"",
"Univ. of Orsay, France"
]
] |
The relationship between the pionium lifetime and the $\pi\pi$ scattering lengths is established, including the sizable electromagnetic corrections. The bound state formalism that is used is that of constraint theory which provides a covariant three-dimensional reduction of the Bethe--Salpeter equation. The framework of generalized chiral perturbation theory allows then an analysis of the lifetime value as a function of the $\pi\pi$ scattering lengths, the latter being dependent on the quark condensate value.
|
2211.00710
|
Vladimir Skokov
|
Gregory Johnson, Fabian Rennecke, Vladimir V. Skokov
|
Universal location of Yang-Lee edge singularity in classic O(N)
universality classes
|
36 pages; 6 figures; version accepted for publication
|
Phys. Rev. D 107, 116013, 2023
|
10.1103/PhysRevD.107.116013
| null |
hep-ph cond-mat.stat-mech
|
http://creativecommons.org/licenses/by/4.0/
|
Employing the functional renormalization group approach at next-to-leading
order of the derivative expansion, we refine our earlier findings for the
location of the Yang-Lee edge singularity in classic O(N) universality classes.
For the universality classes of interest to QCD, in three dimensions, we found
$|z_c|/R_\chi^{1/\gamma} = 1.612(9),\ 1.597(3)$ for $N=2$, $4$ correspondingly.
We also established $|z_c| = 2.04(8),\ 1.69(3)$ for $N=2$, $4$ albeit with
greater systematic error.
|
[
{
"created": "Tue, 1 Nov 2022 19:20:57 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Jun 2023 19:48:42 GMT",
"version": "v2"
}
] |
2023-06-16
|
[
[
"Johnson",
"Gregory",
""
],
[
"Rennecke",
"Fabian",
""
],
[
"Skokov",
"Vladimir V.",
""
]
] |
Employing the functional renormalization group approach at next-to-leading order of the derivative expansion, we refine our earlier findings for the location of the Yang-Lee edge singularity in classic O(N) universality classes. For the universality classes of interest to QCD, in three dimensions, we found $|z_c|/R_\chi^{1/\gamma} = 1.612(9),\ 1.597(3)$ for $N=2$, $4$ correspondingly. We also established $|z_c| = 2.04(8),\ 1.69(3)$ for $N=2$, $4$ albeit with greater systematic error.
|
hep-ph/0502206
|
V. Gogohia
|
V. Gogohia
|
The mass gap and gluon confinement
|
13 pages, no figures, no tables, substantial clarifications
introduced as well as three new references added
| null | null | null |
hep-ph hep-th
| null |
In our previous publication [1-3] it has been proven that the general
iteration solution of the Shwinger-Dyson equation for the full gluon propagator
(i.e., when the skeleton loop integrals, contributing into the gluon
self-energy, have to be iterated, which means that no any
truncations/approximations have been made) can be algebraically (i.e., exactly)
decomposed as the sum of the two principally different terms. The first term is
the Laurent expansion in integer powers of severe (i.e., more singular than
$1/q^2$) infrared singularities accompanied by the corresponding powers of the
mass gap and multiplied by the corresponding residues. The standard second term
is always as much singular as $1/q^2$ and otherwise remaining undetermined.
Here it is explicitly shown that the infrared renormalization of the mass gap
only is needed to render theory free of all severe infrared singularities in
the gluon sector. Moreover, this leads to the gluon confinement criterion in a
gauge-invariant way. As a result of the infrared renormalization of the mass
gap in the initial Laurent expansion, that is dimensionally regularized, the
simplest severe infrared singularity $(q^2)^{-2}$ survives only. It is
multiplied by the mass gap squared, which is the scale responsible for the
large scale structure of the true QCD vacuum. The $\delta$-type regularization
of the simplest severe infrared singularity (and its generalization for the
multi-loop skeleton integrals) is provided by the dimensional regularization
method correctly implemented into the theory of distributions. This makes it
possible to formulate exactly and explicitly the full gluon propagator (up to
its unimportant perturbative part).
|
[
{
"created": "Tue, 22 Feb 2005 13:55:28 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Jun 2005 12:22:49 GMT",
"version": "v2"
},
{
"created": "Thu, 12 Jan 2006 14:34:22 GMT",
"version": "v3"
}
] |
2007-05-23
|
[
[
"Gogohia",
"V.",
""
]
] |
In our previous publication [1-3] it has been proven that the general iteration solution of the Shwinger-Dyson equation for the full gluon propagator (i.e., when the skeleton loop integrals, contributing into the gluon self-energy, have to be iterated, which means that no any truncations/approximations have been made) can be algebraically (i.e., exactly) decomposed as the sum of the two principally different terms. The first term is the Laurent expansion in integer powers of severe (i.e., more singular than $1/q^2$) infrared singularities accompanied by the corresponding powers of the mass gap and multiplied by the corresponding residues. The standard second term is always as much singular as $1/q^2$ and otherwise remaining undetermined. Here it is explicitly shown that the infrared renormalization of the mass gap only is needed to render theory free of all severe infrared singularities in the gluon sector. Moreover, this leads to the gluon confinement criterion in a gauge-invariant way. As a result of the infrared renormalization of the mass gap in the initial Laurent expansion, that is dimensionally regularized, the simplest severe infrared singularity $(q^2)^{-2}$ survives only. It is multiplied by the mass gap squared, which is the scale responsible for the large scale structure of the true QCD vacuum. The $\delta$-type regularization of the simplest severe infrared singularity (and its generalization for the multi-loop skeleton integrals) is provided by the dimensional regularization method correctly implemented into the theory of distributions. This makes it possible to formulate exactly and explicitly the full gluon propagator (up to its unimportant perturbative part).
|
1802.01611
|
John Cherry Jr.
|
John F. Cherry and Ian Shoemaker
|
A Sterile Neutrino Origin for the Upward Directed Cosmic Ray Showers
Detected by ANITA
|
5 pages and 4 figures. This paper has been altered from the previous
draft after a significant typographical error was discovered in the ANITA
collaboration's published description of their detector model, which was used
as input for the previous version of our analysis. The error has been
corrected in the updated analysis shown in this draft, altering our results
and conclusions
|
Phys. Rev. D 99, 063016 (2019)
|
10.1103/PhysRevD.99.063016
| null |
hep-ph astro-ph.HE
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The ANITA balloon experiment has recently observed several ~EeV cascade
events at an angle below the horizon that renders any Standard Model (SM)
interpretation unlikely as the Earth is significantly opaque to all SM
particles at such energies. In this paper, we study a sterile neutrino
interpretation of these events, calculating the angular acceptance of cascades
and the relative sensitivities of several experiments to a cascade initiated by
an EeV sterile neutrino. We find that ANITA is uniquely sensitive to this type
of upward directed cascade signal over a wide portion of the sky and from the
direction of the two observed events has a transient acceptance roughly
equivalent to that of the IceCube experiment.
|
[
{
"created": "Mon, 5 Feb 2018 19:22:35 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Aug 2018 19:52:11 GMT",
"version": "v2"
}
] |
2019-03-27
|
[
[
"Cherry",
"John F.",
""
],
[
"Shoemaker",
"Ian",
""
]
] |
The ANITA balloon experiment has recently observed several ~EeV cascade events at an angle below the horizon that renders any Standard Model (SM) interpretation unlikely as the Earth is significantly opaque to all SM particles at such energies. In this paper, we study a sterile neutrino interpretation of these events, calculating the angular acceptance of cascades and the relative sensitivities of several experiments to a cascade initiated by an EeV sterile neutrino. We find that ANITA is uniquely sensitive to this type of upward directed cascade signal over a wide portion of the sky and from the direction of the two observed events has a transient acceptance roughly equivalent to that of the IceCube experiment.
|
1011.6249
|
Carole Weydert ms
|
Carole Weydert
|
Associated production of top quarks and charged Higgs bosons at
next-to-leading order
|
3 pages, Top2010 Workshop Proceeding
|
IL NUOVO CIMENTO Vol.33 C, N.4 (2010)
|
10.1393/ncc/i2010-10672-3
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Accurate predictions for both signal and background events at the LHC are of
paramount importance in order to confirm even the smallest deviations from
Standard Model predictions. Next-to-leading order Monte Carlo event generators
are an essential tool to reach that goal. Concerning the charged Higgs boson,
NLO calculations of the production cross section already exist. Reiterating the
calculation using a subtraction formalism enables us to implement the cross
section into Monte Carlo generators, which can then be used by experiments.
|
[
{
"created": "Mon, 29 Nov 2010 14:51:18 GMT",
"version": "v1"
}
] |
2010-11-30
|
[
[
"Weydert",
"Carole",
""
]
] |
Accurate predictions for both signal and background events at the LHC are of paramount importance in order to confirm even the smallest deviations from Standard Model predictions. Next-to-leading order Monte Carlo event generators are an essential tool to reach that goal. Concerning the charged Higgs boson, NLO calculations of the production cross section already exist. Reiterating the calculation using a subtraction formalism enables us to implement the cross section into Monte Carlo generators, which can then be used by experiments.
|
1311.0740
|
Gaber Faisel Dr
|
Gaber Faisel
|
Charged Higgs contribution to $\bar{B}_s \rightarrow \phi \pi^0 $ and
$\bar{B}_s \rightarrow \phi \rho^0 $
|
22 pages,4 figures. Accepted version for publication in Physics
Letters B
|
Phys.Lett. B731 (2014) 279-286
|
10.1016/j.physletb.2014.02.050
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the decay modes $\bar{B}_s\to \phi \pi^0$ and $\bar{B}_s\to \phi
\rho^0$ within the frameworks of two-Higgs doublet models type-II and typ-III.
We adopt in our study Soft Collinear Effective Theory as a framework for the
calculation of the amplitudes. We derive the contributions of the charged Higgs
mediation to the weak effective Hamiltonian governing the decay processes in
both models. Moreover we analyze the effect of the charged Higgs mediation on
the Wilson coefficients of the electrowek penguins and on the branching ratios
of $\bar{B}_s\to \phi \pi^0$ and $\bar{B}_s\to \phi \rho^0$ decays. We show
that wthin two-Higgs doublet models type-II and type-III the Wilson
coefficients corresponding to the electroweak penguins can be enhanced due to
the contributions from the charged Higgs mediation leading into enhancement in
the branching ratios of $ \bar{B}_s\to \phi \pi^0$ and $\bar{B}_s\to \phi
\rho^0 $ decays. We find that, within two-Higgs doublet models type-II, the
enhancement in the branching ratio of $\bar{B}_s\to \phi \pi^0$ can not exceed
$18\%$ with respect to the SM predictions. For the branching ratio of
$\bar{B}_s\to \phi \rho^0$, we find that the charged Higgs contribution in this
case is small where the branching ratio of $\bar{B}_s\to \phi \rho^0$ can be
enhanced or reduced by about $4\% $ with respect to the SM predictions. For the
case of the two-Higgs doublet models type-III we show that the branching ratio
of $\bar{B}_s\to \phi \pi^0$ can be enhanced by about a factor $2$ of its value
within two-Higgs doublet models type-II. However no sizable enhancement with
respect to the SM predictions can be obtained for both $\bar{B}_s\to \phi
\pi^0$ and $\bar{B}_s\to \phi \rho^0$ decays.
|
[
{
"created": "Mon, 4 Nov 2013 15:53:21 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Nov 2013 16:40:16 GMT",
"version": "v2"
},
{
"created": "Tue, 4 Mar 2014 14:33:51 GMT",
"version": "v3"
},
{
"created": "Mon, 17 Mar 2014 10:07:38 GMT",
"version": "v4"
}
] |
2014-04-10
|
[
[
"Faisel",
"Gaber",
""
]
] |
We study the decay modes $\bar{B}_s\to \phi \pi^0$ and $\bar{B}_s\to \phi \rho^0$ within the frameworks of two-Higgs doublet models type-II and typ-III. We adopt in our study Soft Collinear Effective Theory as a framework for the calculation of the amplitudes. We derive the contributions of the charged Higgs mediation to the weak effective Hamiltonian governing the decay processes in both models. Moreover we analyze the effect of the charged Higgs mediation on the Wilson coefficients of the electrowek penguins and on the branching ratios of $\bar{B}_s\to \phi \pi^0$ and $\bar{B}_s\to \phi \rho^0$ decays. We show that wthin two-Higgs doublet models type-II and type-III the Wilson coefficients corresponding to the electroweak penguins can be enhanced due to the contributions from the charged Higgs mediation leading into enhancement in the branching ratios of $ \bar{B}_s\to \phi \pi^0$ and $\bar{B}_s\to \phi \rho^0 $ decays. We find that, within two-Higgs doublet models type-II, the enhancement in the branching ratio of $\bar{B}_s\to \phi \pi^0$ can not exceed $18\%$ with respect to the SM predictions. For the branching ratio of $\bar{B}_s\to \phi \rho^0$, we find that the charged Higgs contribution in this case is small where the branching ratio of $\bar{B}_s\to \phi \rho^0$ can be enhanced or reduced by about $4\% $ with respect to the SM predictions. For the case of the two-Higgs doublet models type-III we show that the branching ratio of $\bar{B}_s\to \phi \pi^0$ can be enhanced by about a factor $2$ of its value within two-Higgs doublet models type-II. However no sizable enhancement with respect to the SM predictions can be obtained for both $\bar{B}_s\to \phi \pi^0$ and $\bar{B}_s\to \phi \rho^0$ decays.
|
hep-ph/9909221
|
Yuan Feng
|
Feng Yuan, Hui-Shi Dong, Li-Kun Hao, Kuang-Ta Chao (PKU)
|
Inelastic $J/\psi$ production in polarized photon-hadron collisions
|
14pages, 6 PS figures
|
Phys.Rev.D61:114013,2000
|
10.1103/PhysRevD.61.114013
| null |
hep-ph
| null |
Presented here is a calculation of inelastic $J/\psi$ production in polarized
photon-hadron collisions under the framework of NRQCD factorization formalism.
We consider the photoproduction of $\jpsi$ in the energy range relevant to
HERA. The Weizs\"acker-Williams approximation is adopted in the evaluation of
the cross sections for $ep$ collisions. We found that this process can give
another independent test for the color-octet mechanism, and the different
features for the two color-octet processes may provide further informations on
the mechanism for inelastic $\jpsi$ photoproduction. And the discrepancy on the
production asymmetry $A$ between various sets of polarized gluon distribution
functions is also found to be distinctive.
|
[
{
"created": "Thu, 2 Sep 1999 07:41:52 GMT",
"version": "v1"
}
] |
2011-03-23
|
[
[
"Yuan",
"Feng",
"",
"PKU"
],
[
"Dong",
"Hui-Shi",
"",
"PKU"
],
[
"Hao",
"Li-Kun",
"",
"PKU"
],
[
"Chao",
"Kuang-Ta",
"",
"PKU"
]
] |
Presented here is a calculation of inelastic $J/\psi$ production in polarized photon-hadron collisions under the framework of NRQCD factorization formalism. We consider the photoproduction of $\jpsi$ in the energy range relevant to HERA. The Weizs\"acker-Williams approximation is adopted in the evaluation of the cross sections for $ep$ collisions. We found that this process can give another independent test for the color-octet mechanism, and the different features for the two color-octet processes may provide further informations on the mechanism for inelastic $\jpsi$ photoproduction. And the discrepancy on the production asymmetry $A$ between various sets of polarized gluon distribution functions is also found to be distinctive.
|
1003.5530
|
Achim G\"utlein
|
A. G\"utlein, C. Ciemniak, F. von Feilitzsch, N. Haag, M. Hofmann, C.
Isaila, T. Lachenmaier, J.-C. Lanfranchi, L. Oberauer, S. Pfister, W. Potzel,
S. Roth, M. von Sivers, R. Strau{\ss}, and A. Z\"oller
|
Solar and Atmospheric Neutrinos: Background Sources for the Direct Dark
Matter Searches
|
accepted by Astroparticle Physics
|
Astropart.Phys.34:90-96,2010
|
10.1016/j.astropartphys.2010.06.002
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In experiments for direct dark matter searches, neutrinos coherently
scattering off nuclei can produce similar events as Weakly Interacting Massive
Particles (WIMPs). The calculated count rate for solar neutrinos in such
experiments is a few events per ton-year. This count rate strongly depends on
the nuclear recoil energy threshold achieved in the experiments for the WIMP
search. We show that solar neutrinos can be a serious background source for
direct dark matter search experiments using Ge, Ar, Xe and CaWO_4 as target
materials. To reach sensitivities better than approximatly 10^-10 pb for the
elastic WIMP nucleon spin-independent cross section in the zero-background
limit, energy thresholds for nuclear recoils should be approximatly >2.05 keV
for CaWO_4, >4.91 keV for Ge, >2.89 keV for Xe, and >8.62 keV for Ar as target
material. Next-generation experiments should not only strive for a reduction of
the present energy thresholds but mainly focus on an increase of the target
mass. Atmospheric neutrinos limit the achievable sensitivity for the
background-free direct dark matter search to approximatly >10^-12 pb.
|
[
{
"created": "Mon, 29 Mar 2010 13:00:07 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Jun 2010 08:19:45 GMT",
"version": "v2"
},
{
"created": "Tue, 22 Jun 2010 14:24:59 GMT",
"version": "v3"
}
] |
2010-09-21
|
[
[
"Gütlein",
"A.",
""
],
[
"Ciemniak",
"C.",
""
],
[
"von Feilitzsch",
"F.",
""
],
[
"Haag",
"N.",
""
],
[
"Hofmann",
"M.",
""
],
[
"Isaila",
"C.",
""
],
[
"Lachenmaier",
"T.",
""
],
[
"Lanfranchi",
"J. -C.",
""
],
[
"Oberauer",
"L.",
""
],
[
"Pfister",
"S.",
""
],
[
"Potzel",
"W.",
""
],
[
"Roth",
"S.",
""
],
[
"von Sivers",
"M.",
""
],
[
"Strauß",
"R.",
""
],
[
"Zöller",
"A.",
""
]
] |
In experiments for direct dark matter searches, neutrinos coherently scattering off nuclei can produce similar events as Weakly Interacting Massive Particles (WIMPs). The calculated count rate for solar neutrinos in such experiments is a few events per ton-year. This count rate strongly depends on the nuclear recoil energy threshold achieved in the experiments for the WIMP search. We show that solar neutrinos can be a serious background source for direct dark matter search experiments using Ge, Ar, Xe and CaWO_4 as target materials. To reach sensitivities better than approximatly 10^-10 pb for the elastic WIMP nucleon spin-independent cross section in the zero-background limit, energy thresholds for nuclear recoils should be approximatly >2.05 keV for CaWO_4, >4.91 keV for Ge, >2.89 keV for Xe, and >8.62 keV for Ar as target material. Next-generation experiments should not only strive for a reduction of the present energy thresholds but mainly focus on an increase of the target mass. Atmospheric neutrinos limit the achievable sensitivity for the background-free direct dark matter search to approximatly >10^-12 pb.
|
hep-ph/9803283
|
Gian Paolo Vacca
|
G. P. Vacca
|
The hard QCD Pomeron: some aspects of its phenomenology and interactions
|
PhD thesis, 110 pages, LATEX, 22 PostScript figures included with
epsfig Some minor errors corrected
| null | null | null |
hep-ph
| null |
The Regge limit in perturbative QCD for processes as DIS (low x) and photon
or onia-particles scattering is considered. In the first part a
phenomenological approach for the inclusion of the running coupling, preserving
the gluon reggeization property, is analyzed. In particular the spectrum of the
hard pomeron equation and the asymptotic form of the solution are used to study
scattering processes with also inclusive jet production. The singlet part of
the proton structure function is evolved towards the low x region according to
the full equation. In the second part the problem of unitarity in the QCD is
considered. Following the general Bartels approach the four reggeized gluon
system is studied in the large number of colours limit. The interplay between
double pomeron exchange and triple pomeron vertex contributions is studied. The
conformal invariance of the three pomeron vertex is shown in terms of a
building block function, and the coupling to pomerons has been considered to
make contact with the colour dipole picture which presents a similar triple
pomeron interaction. It is also shown that in the A.H. Mueller approach his
equation for higher order colour dipole densities leads to solutions which can
be represented as fan diagrams with only triple pomeron vertices. Finally we
draw some conclusion and open problems.
|
[
{
"created": "Mon, 9 Mar 1998 12:33:59 GMT",
"version": "v1"
},
{
"created": "Mon, 11 May 1998 00:24:08 GMT",
"version": "v2"
}
] |
2007-05-23
|
[
[
"Vacca",
"G. P.",
""
]
] |
The Regge limit in perturbative QCD for processes as DIS (low x) and photon or onia-particles scattering is considered. In the first part a phenomenological approach for the inclusion of the running coupling, preserving the gluon reggeization property, is analyzed. In particular the spectrum of the hard pomeron equation and the asymptotic form of the solution are used to study scattering processes with also inclusive jet production. The singlet part of the proton structure function is evolved towards the low x region according to the full equation. In the second part the problem of unitarity in the QCD is considered. Following the general Bartels approach the four reggeized gluon system is studied in the large number of colours limit. The interplay between double pomeron exchange and triple pomeron vertex contributions is studied. The conformal invariance of the three pomeron vertex is shown in terms of a building block function, and the coupling to pomerons has been considered to make contact with the colour dipole picture which presents a similar triple pomeron interaction. It is also shown that in the A.H. Mueller approach his equation for higher order colour dipole densities leads to solutions which can be represented as fan diagrams with only triple pomeron vertices. Finally we draw some conclusion and open problems.
|
2408.04100
|
Jefferson M. A. Paix\~ao
|
Jefferson Mendes Aguiar Paix\~ao
|
Axions, Photons and Physics Beyond the Standard Model
|
PhD Thesis
| null | null | null |
hep-ph hep-th
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
In this thesis, we re-assess some aspects of axionic electrodynamics by
coupling non-linear electromagnetic effects to axion physics. We present a
number of motivations to justify the coupling of the axion to the photon in
terms of a general non-linear extension of the electromagnetic sector. Our
emphasis in the paper relies on the investigation of the constitutive
permittivity and permeability tensors, for which the axion contribution
introduces a dependence on the frequency and wave vector of the propagating
radiation. Also, we point out how the axion mass and the axion-photon coupling
constant contribute to a dispersive behavior of the electromagnetic waves, in
contrast to what happens in the case of non-linear extensions, when effective
refractive indices appear which depend only on the direction of the propagation
with respect to the external fields. The axion changes this picture by yielding
refractive indices with dependence on the wavelength. We apply our results to
the special case of the Born-Infeld Electrodynamics and we show that it becomes
birefringent whenever the axion is coupled. We also include in our analysis the
Lorentz violation phenomenon through a Carroll-Field-Jackiw term, where we
investigate the influence of this sector on the dispersion relations, and
consequently, on the optical phenomena.
|
[
{
"created": "Wed, 7 Aug 2024 21:33:56 GMT",
"version": "v1"
}
] |
2024-08-09
|
[
[
"Paixão",
"Jefferson Mendes Aguiar",
""
]
] |
In this thesis, we re-assess some aspects of axionic electrodynamics by coupling non-linear electromagnetic effects to axion physics. We present a number of motivations to justify the coupling of the axion to the photon in terms of a general non-linear extension of the electromagnetic sector. Our emphasis in the paper relies on the investigation of the constitutive permittivity and permeability tensors, for which the axion contribution introduces a dependence on the frequency and wave vector of the propagating radiation. Also, we point out how the axion mass and the axion-photon coupling constant contribute to a dispersive behavior of the electromagnetic waves, in contrast to what happens in the case of non-linear extensions, when effective refractive indices appear which depend only on the direction of the propagation with respect to the external fields. The axion changes this picture by yielding refractive indices with dependence on the wavelength. We apply our results to the special case of the Born-Infeld Electrodynamics and we show that it becomes birefringent whenever the axion is coupled. We also include in our analysis the Lorentz violation phenomenon through a Carroll-Field-Jackiw term, where we investigate the influence of this sector on the dispersion relations, and consequently, on the optical phenomena.
|
2108.03304
|
Jordan Roth
|
Jordan Roth
|
Towards a study of the effects of dynamical factorization breaking at
LHCb
|
7 pages, 2 figures, proceedings for DIS2021
| null | null | null |
hep-ph hep-ex
|
http://creativecommons.org/licenses/by/4.0/
|
The factorization of short-distance partonic cross-sections from universal
long-distance kinematic distributions is fundamental to phenomenology at hadron
colliders. It has been predicted however that observables sensitive to momenta
transverse to the direction of an energetic parton cannot be factorized in the
usual way, even at high energies. It should be possible to study this
factorization breaking using Z+jet production in high-energy proton-proton
collisions by studying azimuthal correlations between a Z boson and associated
charged hadrons. A plan to perform this measurement with data collected by LHCb
will be discussed, along with related work.
|
[
{
"created": "Fri, 6 Aug 2021 20:59:13 GMT",
"version": "v1"
}
] |
2021-08-10
|
[
[
"Roth",
"Jordan",
""
]
] |
The factorization of short-distance partonic cross-sections from universal long-distance kinematic distributions is fundamental to phenomenology at hadron colliders. It has been predicted however that observables sensitive to momenta transverse to the direction of an energetic parton cannot be factorized in the usual way, even at high energies. It should be possible to study this factorization breaking using Z+jet production in high-energy proton-proton collisions by studying azimuthal correlations between a Z boson and associated charged hadrons. A plan to perform this measurement with data collected by LHCb will be discussed, along with related work.
|
1610.01214
|
Igor Shovkovy
|
E. V. Gorbar, I. Rudenok, I. A. Shovkovy, S. Vilchinskii
|
Anomaly-driven inverse cascade and inhomogeneities in a magnetized
chiral plasma in the early Universe
|
9 pages, 5 multipanel figures
|
Phys. Rev. D 94, 103528 (2016)
|
10.1103/PhysRevD.94.103528
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
By making use of a simple model that captures the key features of the
anomalous Maxwell equations, we study the role of inhomogeneities on the
evolution of magnetic fields in a chiral plasma. We find that inhomogeneities
of the chiral asymmetry by themselves do not prevent the anomaly-driven inverse
cascade and, as in the homogeneous case, the magnetic helicity is transferred
from shorter to longer wavelength helical modes of the magnetic field. However,
we also find that the evolution appears to be sensitive to the effects of
diffusion. In the case when diffusion is negligible, the inverse cascade slows
down considerably compared to the homogeneous scenario. In the case of the
primordial plasma, though, we find that the diffusion is substantial and
efficiently suppresses chiral asymmetry inhomogeneities. As a result, the
inverse cascade proceeds practically in the same way as in the chirally
homogeneous model.
|
[
{
"created": "Tue, 4 Oct 2016 21:40:14 GMT",
"version": "v1"
}
] |
2016-12-07
|
[
[
"Gorbar",
"E. V.",
""
],
[
"Rudenok",
"I.",
""
],
[
"Shovkovy",
"I. A.",
""
],
[
"Vilchinskii",
"S.",
""
]
] |
By making use of a simple model that captures the key features of the anomalous Maxwell equations, we study the role of inhomogeneities on the evolution of magnetic fields in a chiral plasma. We find that inhomogeneities of the chiral asymmetry by themselves do not prevent the anomaly-driven inverse cascade and, as in the homogeneous case, the magnetic helicity is transferred from shorter to longer wavelength helical modes of the magnetic field. However, we also find that the evolution appears to be sensitive to the effects of diffusion. In the case when diffusion is negligible, the inverse cascade slows down considerably compared to the homogeneous scenario. In the case of the primordial plasma, though, we find that the diffusion is substantial and efficiently suppresses chiral asymmetry inhomogeneities. As a result, the inverse cascade proceeds practically in the same way as in the chirally homogeneous model.
|
hep-ph/9704268
|
Silvano Simula
|
D. Melikhov, N. Nikitin and S. Simula
|
Rare decays B -> (K, K*) (l+ l-, nu bar{nu}) in the quark model
|
revised version to appear in Physics Letters B. No conclusions have
been changed
|
Phys.Lett. B410 (1997) 290-298
|
10.1016/S0370-2693(97)00928-3
|
preprint INFN-ISS 97/2
|
hep-ph
| null |
Long-distance effects in exclusive rare semileptonic transitions B -> (K, K*)
are analysed within a relativistic quark model. The meson transition form
factors, describing the meson amplitudes of the effective weak Hamiltonian, are
calculated within the dispersion formulation of the quark model as relativistic
double spectral representations through the wave functions of the initial and
final mesons. The dilepton spectra and lepton asymmetries are considered within
the framework provided by the Standard Model. It is found that, while the
non-resonant decay rates are very sensitive to quark model parameters, the
model dependence of the predicted dilepton forward-backward and lepton
polarization asymmetries is remarkably small, providing only an overall ~10%
uncertainty.
|
[
{
"created": "Wed, 9 Apr 1997 09:26:35 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Aug 1997 13:00:24 GMT",
"version": "v2"
}
] |
2009-10-30
|
[
[
"Melikhov",
"D.",
""
],
[
"Nikitin",
"N.",
""
],
[
"Simula",
"S.",
""
]
] |
Long-distance effects in exclusive rare semileptonic transitions B -> (K, K*) are analysed within a relativistic quark model. The meson transition form factors, describing the meson amplitudes of the effective weak Hamiltonian, are calculated within the dispersion formulation of the quark model as relativistic double spectral representations through the wave functions of the initial and final mesons. The dilepton spectra and lepton asymmetries are considered within the framework provided by the Standard Model. It is found that, while the non-resonant decay rates are very sensitive to quark model parameters, the model dependence of the predicted dilepton forward-backward and lepton polarization asymmetries is remarkably small, providing only an overall ~10% uncertainty.
|
2108.04377
|
Oliver Gould
|
Oliver Gould and Joonas Hirvonen
|
Effective field theory approach to thermal bubble nucleation
|
32 pages, 3 figures
|
Phys.Rev.D 104 (2021) 9, 096015
|
10.1103/PhysRevD.104.096015
|
HIP-2020-19/TH
|
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The standard vacuum bounce formalism suffers from inconsistencies when
applied to thermal bubble nucleation, for which ad hoc workarounds are commonly
adopted. Identifying the length scales on which nucleation takes place, we
demonstrate how the construction of an effective description for these scales
naturally resolves the problems of the standard vacuum bounce formalism.
Further, by utilising high-temperature dimensional reduction, we make a
connection to classical nucleation theory. This offers a clear physical picture
of thermal bubble nucleation, as well as a computational framework which can
then be pushed to higher accuracy. We demonstrate the method for three
qualitatively different quantum field theories.
|
[
{
"created": "Mon, 9 Aug 2021 22:29:26 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Dec 2021 14:55:28 GMT",
"version": "v2"
}
] |
2021-12-09
|
[
[
"Gould",
"Oliver",
""
],
[
"Hirvonen",
"Joonas",
""
]
] |
The standard vacuum bounce formalism suffers from inconsistencies when applied to thermal bubble nucleation, for which ad hoc workarounds are commonly adopted. Identifying the length scales on which nucleation takes place, we demonstrate how the construction of an effective description for these scales naturally resolves the problems of the standard vacuum bounce formalism. Further, by utilising high-temperature dimensional reduction, we make a connection to classical nucleation theory. This offers a clear physical picture of thermal bubble nucleation, as well as a computational framework which can then be pushed to higher accuracy. We demonstrate the method for three qualitatively different quantum field theories.
|
hep-ph/9504316
| null |
M. Carena, J.R. Espinosa, M. Quiros and C.E.M. Wagner
|
ANALYTICAL EXPRESSIONS FOR RADIATIVELY CORRECTED HIGGS MASSES AND
COUPLINGS IN THE MSSM
|
An old version of Fig. 5 was inadvertently included in the uuencoded
tar-compressed file fig.uu. The correct Fig. 5 has been replaced in the new
fig.uu
|
Phys.Lett.B355:209-221,1995
|
10.1016/0370-2693(95)00694-G
|
CERN-TH/95-45; DESY 95-038
|
hep-ph
| null |
We propose, for the computation of the Higgs mass spectrum and couplings, a
renormalization-group improved leading-log approximation, where the
renormalization scale is fixed to the top-quark pole mass. For the case
$m_A\sim M_{\rm SUSY}$, our leading-log approximation differs by less than 2
GeV from previous results on the Higgs mass computed using a nearly scale
independent renormalization-group improved effective potential up to
next-to-leading order. Moreover, for the general case $m_A\simlt M_{\rm SUSY}$,
we provide analytical formulae (including two-loop leading-log corrections) for
all the masses and couplings in the Higgs sector. For $M_{\rm SUSY}\simlt 1.5$
TeV and arbitrary values of $m_A$, $\tan\beta$ and the stop mixing parameters,
they reproduce the numerical renormalization-group improved leading-log result
for the Higgs masses with an error of less than 3 GeV. For the Higgs couplings,
our analytical formulae reproduce the numerical results equally well.
Comparison with other methods is also performed.
|
[
{
"created": "Mon, 17 Apr 1995 20:26:35 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Apr 1995 12:49:32 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Carena",
"M.",
""
],
[
"Espinosa",
"J. R.",
""
],
[
"Quiros",
"M.",
""
],
[
"Wagner",
"C. E. M.",
""
]
] |
We propose, for the computation of the Higgs mass spectrum and couplings, a renormalization-group improved leading-log approximation, where the renormalization scale is fixed to the top-quark pole mass. For the case $m_A\sim M_{\rm SUSY}$, our leading-log approximation differs by less than 2 GeV from previous results on the Higgs mass computed using a nearly scale independent renormalization-group improved effective potential up to next-to-leading order. Moreover, for the general case $m_A\simlt M_{\rm SUSY}$, we provide analytical formulae (including two-loop leading-log corrections) for all the masses and couplings in the Higgs sector. For $M_{\rm SUSY}\simlt 1.5$ TeV and arbitrary values of $m_A$, $\tan\beta$ and the stop mixing parameters, they reproduce the numerical renormalization-group improved leading-log result for the Higgs masses with an error of less than 3 GeV. For the Higgs couplings, our analytical formulae reproduce the numerical results equally well. Comparison with other methods is also performed.
|
1301.7555
|
Sergei Gninenko
|
S.N. Gninenko
|
Constraints on dark photons from $\pi^0$ decays
|
4 pages, 2 figures, to appear in PRD
|
Phys.Rev. D87 (2013) 035030
|
10.1103/PhysRevD.87.035030
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Several models of dark matter suggest the existence of hidden sectors
consisting of SU(3)_C x SU(2)_L x U(1)_Y singlet fields. The interaction
between the ordinary and hidden sectors could be transmitted by new Abelian
U'(1) gauge bosons A' (dark or hidden photons) mixing with ordinary photons. If
such A's have masses below the \pi^0 meson mass, they would be produced through
\gamma - A' mixing in the \pi^0 ->2\gamma - decays and be observed via their
decays A' -> e+e- in a detector. Using bounds from the SINDRUM experiment at
the Paul Scherrer Institute that searched for an excess of e+e- pairs in \pi^-
p interactions at rest, the area excluding the \gamma - A' mixing \epsilon >
10^{-3} for the A' mass region 25 < M_{A'} < 120 MeV is derived.
|
[
{
"created": "Thu, 31 Jan 2013 09:10:09 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Feb 2013 14:08:51 GMT",
"version": "v2"
},
{
"created": "Wed, 20 Feb 2013 05:51:52 GMT",
"version": "v3"
}
] |
2015-06-12
|
[
[
"Gninenko",
"S. N.",
""
]
] |
Several models of dark matter suggest the existence of hidden sectors consisting of SU(3)_C x SU(2)_L x U(1)_Y singlet fields. The interaction between the ordinary and hidden sectors could be transmitted by new Abelian U'(1) gauge bosons A' (dark or hidden photons) mixing with ordinary photons. If such A's have masses below the \pi^0 meson mass, they would be produced through \gamma - A' mixing in the \pi^0 ->2\gamma - decays and be observed via their decays A' -> e+e- in a detector. Using bounds from the SINDRUM experiment at the Paul Scherrer Institute that searched for an excess of e+e- pairs in \pi^- p interactions at rest, the area excluding the \gamma - A' mixing \epsilon > 10^{-3} for the A' mass region 25 < M_{A'} < 120 MeV is derived.
|
hep-ph/9512234
|
Ulf Meissner
|
V. Bernard, N. Kaiser, Ulf-G. Mei{\ss}ner
|
Chiral symmetry and the reaction $\gamma p \to \pi^0 p$
|
8 pp, LaTeX/ReVTeX file, 3 figures (in a separate compressed tar
files in pi0fig.uu)
|
Phys.Lett. B378 (1996) 337-341
|
10.1016/0370-2693(96)00356-5
|
CRN 95-38 and TK 95 30
|
hep-ph nucl-th
| null |
We analyze the new threshold data for neutral pion photoproduction off
protons in the framework of heavy baryon chiral perturbation theory. We show
that large loop corrections are needed to understand the S--wave multipole
$E_{0+}$ and that all pertinent low--energy constants can be understood within
the framework of resonance exchange saturation. Previous inconsistencies in the
description of this reaction in the threshold region are resolved.
|
[
{
"created": "Tue, 5 Dec 1995 07:32:01 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Bernard",
"V.",
""
],
[
"Kaiser",
"N.",
""
],
[
"Meißner",
"Ulf-G.",
""
]
] |
We analyze the new threshold data for neutral pion photoproduction off protons in the framework of heavy baryon chiral perturbation theory. We show that large loop corrections are needed to understand the S--wave multipole $E_{0+}$ and that all pertinent low--energy constants can be understood within the framework of resonance exchange saturation. Previous inconsistencies in the description of this reaction in the threshold region are resolved.
|
hep-ph/9405234
| null |
K. Farakos, K. Kajantie, K. Rummukainen and M. Shaposhnikov
|
The Electroweak Phase Transition at $m_H \simeq m_W$
|
CERN-TH.7244/94, IUHET-279, 17 pages (8 figures)
|
Phys.Lett. B336 (1994) 494-501
|
10.1016/0370-2693(94)90563-0
| null |
hep-ph
| null |
We study the finite temperature electroweak transition with non-perturbative
lattice Monte Carlo simulations. We find that it is of first order, at least
for Higgs masses up to 80 GeV. The critical temperature of the phase transition
is found to be smaller than that determined by a 2-loop renormalization group
improved effective potential. The jump of the order parameter at the critical
temperature is considerably larger than the perturbative value. By comparing
lattice data and perturbation theory, we demonstrate that the latter, for the
computation of the vacuum expectation value of the Higgs field $v(T)$ in the
broken phase at given temperature, converges quite well, provided $v(T)/T>1$.
An upper bound on the Higgs mass necessary for electroweak baryogenesis in the
light of the lattice data is briefly discussed.
|
[
{
"created": "Thu, 5 May 1994 15:23:26 GMT",
"version": "v1"
}
] |
2009-10-28
|
[
[
"Farakos",
"K.",
""
],
[
"Kajantie",
"K.",
""
],
[
"Rummukainen",
"K.",
""
],
[
"Shaposhnikov",
"M.",
""
]
] |
We study the finite temperature electroweak transition with non-perturbative lattice Monte Carlo simulations. We find that it is of first order, at least for Higgs masses up to 80 GeV. The critical temperature of the phase transition is found to be smaller than that determined by a 2-loop renormalization group improved effective potential. The jump of the order parameter at the critical temperature is considerably larger than the perturbative value. By comparing lattice data and perturbation theory, we demonstrate that the latter, for the computation of the vacuum expectation value of the Higgs field $v(T)$ in the broken phase at given temperature, converges quite well, provided $v(T)/T>1$. An upper bound on the Higgs mass necessary for electroweak baryogenesis in the light of the lattice data is briefly discussed.
|
hep-ph/0205134
|
Z. Xiao
|
Cai-Dian L\"u and Zhenjun Xiao
|
Constraint on the CKM angle alpha from the experimental measurements of
CP violation in B_d^0 --> pi^+ pi^- decay
|
Revtex, 17 pages with 6 ps/eps figure files, new Babar data Reported
at ICHEP 2002 considered
|
Phys.Rev.D66:074011,2002
|
10.1103/PhysRevD.66.074011
|
BIHEP-TH-2002-22
|
hep-ph hep-ex
| null |
In this paper, we study and try to find the constraint on the CKM angle alpha
from the experimental measurements of CP violation in B_d^0 --> pi^+ pi^-
decay, as reported very recently by BaBar and Belle Collaborations. After
considering uncertainties of the data and the ratio r of penguin over tree
amplitude, we found that strong constraint on both the CKM angle alpha and the
strong phase delta can be obtained from the measured CP asymmetries S_{pi pi}
and A_{pi pi}: (a) the ranges of 87 degrees <= alpha <= 131 degrees and 36
degrees <= delta <= 144 degrees are allowed by 1 sigma of the averaged data for
r = 0.31; (b) for Belle's result alone, the limits on alpha and delta are 104
degrees <= alpha <= 139 degrees and 42 degrees <= delta <= 138 degrees for 0.32
<= r <= 0.41; and (c) the angle alpha larger than 90 degrees is preferred.
|
[
{
"created": "Tue, 14 May 2002 05:44:48 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Jun 2002 02:49:12 GMT",
"version": "v2"
},
{
"created": "Sat, 29 Jun 2002 02:39:19 GMT",
"version": "v3"
},
{
"created": "Mon, 5 Aug 2002 01:07:41 GMT",
"version": "v4"
}
] |
2014-11-17
|
[
[
"Lü",
"Cai-Dian",
""
],
[
"Xiao",
"Zhenjun",
""
]
] |
In this paper, we study and try to find the constraint on the CKM angle alpha from the experimental measurements of CP violation in B_d^0 --> pi^+ pi^- decay, as reported very recently by BaBar and Belle Collaborations. After considering uncertainties of the data and the ratio r of penguin over tree amplitude, we found that strong constraint on both the CKM angle alpha and the strong phase delta can be obtained from the measured CP asymmetries S_{pi pi} and A_{pi pi}: (a) the ranges of 87 degrees <= alpha <= 131 degrees and 36 degrees <= delta <= 144 degrees are allowed by 1 sigma of the averaged data for r = 0.31; (b) for Belle's result alone, the limits on alpha and delta are 104 degrees <= alpha <= 139 degrees and 42 degrees <= delta <= 138 degrees for 0.32 <= r <= 0.41; and (c) the angle alpha larger than 90 degrees is preferred.
|
0705.4029
|
Kwei-Chou Yang
|
Kwei-Chou Yang
|
Branching Ratios and CP Asymmetries of B \to a_1(1260) \pi and a_1(1260)
K Decays
|
20 pages, 1 figure, 4 tables, typos corrected, some discussions
added, version to appear in PRD
|
Phys.Rev.D76:094002,2007
|
10.1103/PhysRevD.76.094002
| null |
hep-ph hep-ex
| null |
We present the studies of the decays $B\to a_1(1260) \pi$ and $a_1(1260) K$
within the framework of QCD factorization. Due to the G-parity, unlike the
vector meson, the chiral-odd two-parton light-cone distribution amplitudes of
the $a_1$ are antisymmetric under the exchange of quark and anti-quark momentum
fractions in the SU(2) limit. The branching ratios for $a_1 \pi$ modes are
sensitive to tree--penguin interference. The resultant ${\cal B}(B^0 \to
a_1^\pm \pi^\mp)$ are in good agreement with the data. However, using the
current Cabibbo--Kobayashi--Maskawa angles, $\beta=22.0^\circ$ and
$\gamma=59.0^\circ$, our results for the mixing-induced parameter $S$ and
$\alpha_{\rm eff}$ differ from the measurements of the time-dependent CP
asymmetries in the decay $B^0\to a_1^\pm \pi^\mp$ at about the $3.7\sigma$
level. This puzzle may be resolved by using a larger $\gamma \gtrsim 80^\circ$.
For $a_1 K$ modes, the annihilation topologies give sizable contributions and
are sensitive to the first Gegenbauer moment of the leading-twist tensor
(chiral-odd) distribution amplitude of the $a_1$ meson. The $B\to a_1 K$
amplitudes resemble the corresponding $B\to \pi K$ ones very much. Taking the
ratios of corresponding CP-averaged $a_1 K$ and $\pi K$ branching ratios, we
can extract information relevant to the electroweak penguins and annihilations.
The existence of new-physics in the electroweak penguin sector and final state
interactions during decays can thus be explored.
|
[
{
"created": "Mon, 28 May 2007 11:31:44 GMT",
"version": "v1"
},
{
"created": "Sun, 23 Sep 2007 00:24:15 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Yang",
"Kwei-Chou",
""
]
] |
We present the studies of the decays $B\to a_1(1260) \pi$ and $a_1(1260) K$ within the framework of QCD factorization. Due to the G-parity, unlike the vector meson, the chiral-odd two-parton light-cone distribution amplitudes of the $a_1$ are antisymmetric under the exchange of quark and anti-quark momentum fractions in the SU(2) limit. The branching ratios for $a_1 \pi$ modes are sensitive to tree--penguin interference. The resultant ${\cal B}(B^0 \to a_1^\pm \pi^\mp)$ are in good agreement with the data. However, using the current Cabibbo--Kobayashi--Maskawa angles, $\beta=22.0^\circ$ and $\gamma=59.0^\circ$, our results for the mixing-induced parameter $S$ and $\alpha_{\rm eff}$ differ from the measurements of the time-dependent CP asymmetries in the decay $B^0\to a_1^\pm \pi^\mp$ at about the $3.7\sigma$ level. This puzzle may be resolved by using a larger $\gamma \gtrsim 80^\circ$. For $a_1 K$ modes, the annihilation topologies give sizable contributions and are sensitive to the first Gegenbauer moment of the leading-twist tensor (chiral-odd) distribution amplitude of the $a_1$ meson. The $B\to a_1 K$ amplitudes resemble the corresponding $B\to \pi K$ ones very much. Taking the ratios of corresponding CP-averaged $a_1 K$ and $\pi K$ branching ratios, we can extract information relevant to the electroweak penguins and annihilations. The existence of new-physics in the electroweak penguin sector and final state interactions during decays can thus be explored.
|
1806.07970
|
Tomokazu Miyamoto
|
Tomokazu Miyamoto and Shigehiro Yasui
|
Hyperspherical-coordinate approach to the spectra and decay widths of
hybrid quarkonia
|
14 pages, 15 figures
|
Phys. Rev. D 98, 094027 (2018)
|
10.1103/PhysRevD.98.094027
| null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
In this paper, we consider the possibility that Y(4260), Y(4360), $
\psi(4415) $ or X(4660) is the ground state or the first excited state of a
hybrid charmonium and examine whether $ \Upsilon ( 10860) $ is the ground state
or the first excited state of a hybrid bottomonium. Under a constituent quark
model, we carry out numerical calculations to obtain the spectra of both
electric gluon and magnetic gluon hybrid quarkonia. We see that the ground
state of a magnetic gluon hybrid charmonium and the first excited state of an
electric gluon hybrid are comparable in energy to $ \psi(4415) $ and that the
first excited states of an electric gluon hybrid bottomonium and the ground
state of a magnetic gluon hybrid appear a few hundred MeV above the mass of $
\Upsilon (10860 ) $. Also, we evaluate the widths of the decays of a hybrid
charmonium into $D^{(*)} \bar{D}^{(*) } $ and those of a hybrid bottomonium
into $ B^{(*) } \bar{B}^{(* ) } $. We show that if the exotic meson candidates
are hybrid charmonia, then they are magnetic gluon ones and argue that it seems
unlikely that $ \Upsilon (10860) $ is the ground state of an electric gluon
hybrid bottomonium.
|
[
{
"created": "Wed, 20 Jun 2018 20:23:28 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Sep 2018 13:44:08 GMT",
"version": "v2"
},
{
"created": "Fri, 30 Nov 2018 06:44:35 GMT",
"version": "v3"
}
] |
2018-12-03
|
[
[
"Miyamoto",
"Tomokazu",
""
],
[
"Yasui",
"Shigehiro",
""
]
] |
In this paper, we consider the possibility that Y(4260), Y(4360), $ \psi(4415) $ or X(4660) is the ground state or the first excited state of a hybrid charmonium and examine whether $ \Upsilon ( 10860) $ is the ground state or the first excited state of a hybrid bottomonium. Under a constituent quark model, we carry out numerical calculations to obtain the spectra of both electric gluon and magnetic gluon hybrid quarkonia. We see that the ground state of a magnetic gluon hybrid charmonium and the first excited state of an electric gluon hybrid are comparable in energy to $ \psi(4415) $ and that the first excited states of an electric gluon hybrid bottomonium and the ground state of a magnetic gluon hybrid appear a few hundred MeV above the mass of $ \Upsilon (10860 ) $. Also, we evaluate the widths of the decays of a hybrid charmonium into $D^{(*)} \bar{D}^{(*) } $ and those of a hybrid bottomonium into $ B^{(*) } \bar{B}^{(* ) } $. We show that if the exotic meson candidates are hybrid charmonia, then they are magnetic gluon ones and argue that it seems unlikely that $ \Upsilon (10860) $ is the ground state of an electric gluon hybrid bottomonium.
|
hep-ph/0005154
|
Bhaskar Dutta
|
R. Arnowitt, B. Dutta and Y. Santoso
|
Neutralino Proton Cross Sections For Dark Matter In SUGRA And D-BRANE
Models
|
14 pages, latex, 11 figures, talk presented at the conference
"Sources and Detection of Dark Matter in the Universe", CA, Feb. 23-25, 2000
| null | null | null |
hep-ph astro-ph
| null |
Neutralino proton cross sections are examined for models with R-parity
invariance with universal soft breaking (mSUGRA) models, nonuniversal SUGRA
models, and D-brane models. The region of parameter space where current dark
matter detectors are sensitive, i.e. $1\times 10^{-6}$ pb, is examined. For
mSUGRA models, detectors are sampling parts of the parametr space for tan$\beta
>\sim 25$. The nonuniversal models can achieve cross sections that are a factor
of 10-100 bigger or smaller then the universal one and in the former case
sample regions tan$\beta >\sim 4$. The D-brane models considered require
tan$\beta >\sim 15$. The inclusion of CP violating phases reduces the cross
section by a factor of $\sim$ 2-3 (but also requires considerable fine tuning
at the GUT scale). The expected particle spectra at accelerators are examined
and seen to differ for each model. Three new regions of possible coannihilation
are noted.
|
[
{
"created": "Tue, 16 May 2000 20:05:27 GMT",
"version": "v1"
}
] |
2016-09-06
|
[
[
"Arnowitt",
"R.",
""
],
[
"Dutta",
"B.",
""
],
[
"Santoso",
"Y.",
""
]
] |
Neutralino proton cross sections are examined for models with R-parity invariance with universal soft breaking (mSUGRA) models, nonuniversal SUGRA models, and D-brane models. The region of parameter space where current dark matter detectors are sensitive, i.e. $1\times 10^{-6}$ pb, is examined. For mSUGRA models, detectors are sampling parts of the parametr space for tan$\beta >\sim 25$. The nonuniversal models can achieve cross sections that are a factor of 10-100 bigger or smaller then the universal one and in the former case sample regions tan$\beta >\sim 4$. The D-brane models considered require tan$\beta >\sim 15$. The inclusion of CP violating phases reduces the cross section by a factor of $\sim$ 2-3 (but also requires considerable fine tuning at the GUT scale). The expected particle spectra at accelerators are examined and seen to differ for each model. Three new regions of possible coannihilation are noted.
|
hep-ph/0410349
|
Anastasios Avgoustidis
|
A. Avgoustidis, E.P.S. Shellard
|
Cosmic String Evolution in Higher Dimensions
|
23 pages, 8 figures. Minor updates and notational clarifications
|
Phys.Rev. D71 (2005) 123513
|
10.1103/PhysRevD.71.123513
| null |
hep-ph astro-ph hep-th
| null |
We obtain the equations of motion for cosmic strings in extensions of the 3+1
FRW model with extra dimensions. From these we derive a generalisation of the
Velocity-dependent One-Scale (VOS) model for cosmic string network evolution
which we apply, first, to a higher-dimensional isotropic $D+1$ FRW model and,
second, to a 3+1 FRW model with static flat extra dimensions. In the former
case the string network does not achieve a scaling regime because of the
diminishing rate of string intersections ($D>3$), but this can be avoided in
the latter case by considering compact, small extra dimensions, for which there
is a reduced but still appreciable string intercommuting probability. We note
that the velocity components lying in the three expanding dimensions are
Hubble-damped, whereas those in the static extra dimensions are only very
weakly damped. This leads to the pathological possibility, in principle, that
string motion in the three infinite dimensions can come to a halt preventing
the strings from intersecting, with the result that scaling is not achieved and
the strings irreversibly dominate the early universe. We note criteria by which
this can be avoided, notably if the spatial structure of the network becomes
essentially three-dimensional, as is expected for string networks produced in
brane inflation. Applying our model to a brane inflation setting, we find
scaling solutions in which the effective 3D string motion does not necessarily
stop, but it is slowed down because of the excitations trapped in the extra
dimensions. These effects are likely to influence cosmic string network
evolution for a long period after formation and we discuss their more general
implications.
|
[
{
"created": "Tue, 26 Oct 2004 18:22:57 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Apr 2005 19:12:45 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Avgoustidis",
"A.",
""
],
[
"Shellard",
"E. P. S.",
""
]
] |
We obtain the equations of motion for cosmic strings in extensions of the 3+1 FRW model with extra dimensions. From these we derive a generalisation of the Velocity-dependent One-Scale (VOS) model for cosmic string network evolution which we apply, first, to a higher-dimensional isotropic $D+1$ FRW model and, second, to a 3+1 FRW model with static flat extra dimensions. In the former case the string network does not achieve a scaling regime because of the diminishing rate of string intersections ($D>3$), but this can be avoided in the latter case by considering compact, small extra dimensions, for which there is a reduced but still appreciable string intercommuting probability. We note that the velocity components lying in the three expanding dimensions are Hubble-damped, whereas those in the static extra dimensions are only very weakly damped. This leads to the pathological possibility, in principle, that string motion in the three infinite dimensions can come to a halt preventing the strings from intersecting, with the result that scaling is not achieved and the strings irreversibly dominate the early universe. We note criteria by which this can be avoided, notably if the spatial structure of the network becomes essentially three-dimensional, as is expected for string networks produced in brane inflation. Applying our model to a brane inflation setting, we find scaling solutions in which the effective 3D string motion does not necessarily stop, but it is slowed down because of the excitations trapped in the extra dimensions. These effects are likely to influence cosmic string network evolution for a long period after formation and we discuss their more general implications.
|
2302.13673
|
Dmitri Melikhov
|
Dmitri Melikhov
|
Three-particle distribution in B meson and charm-quark loops in FCNC B
decays
|
12 pages, a few typos corrected, version to appear in PRD
|
Phys. Rev. D 108 (2023) 034007
|
10.1103/PhysRevD.108.034007
| null |
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
We discuss a nonfactorizable (NF) contribution of a charm loop to the FCNC
$B$-decay amplitude given through the three-particle Bethe-Salpeter amplitude
(3BS) of the $B$-meson. This 3BS contains one heavy-quark field and two light
fields (a light quark and a gluon). Our discussion is aimed at clarifying
properties of the $B$-meson 3BS necessary to describe properly charm-loop
contributions to the amplitudes of FCNC $B$-decays. We demonstrate that the
dominant contribution of nonfactorizable charm to FCNC $B$-decay amplitude is
given in the heavy-quark limit by a convolution of some hard kernel and the
$B$-meson 3BS in a "double-collinear" light cone (LC) configuration: one of the
light degrees of freedom $\phi(x)$, $x^2=0$, lies on the $(+)$-direction of the
LC, whereas another light degree of freedom $\phi'(x')$, $x'^2=0$ lies on the
$(-)$-direction. We show the emergence of new constraints on the distribution
amplitudes which parametrize the 3BS in this double-collinear configuration.
|
[
{
"created": "Mon, 27 Feb 2023 11:16:51 GMT",
"version": "v1"
},
{
"created": "Thu, 11 May 2023 16:28:14 GMT",
"version": "v2"
},
{
"created": "Mon, 15 May 2023 13:20:33 GMT",
"version": "v3"
},
{
"created": "Sun, 2 Jul 2023 17:32:27 GMT",
"version": "v4"
},
{
"created": "Thu, 3 Aug 2023 11:43:46 GMT",
"version": "v5"
}
] |
2023-08-08
|
[
[
"Melikhov",
"Dmitri",
""
]
] |
We discuss a nonfactorizable (NF) contribution of a charm loop to the FCNC $B$-decay amplitude given through the three-particle Bethe-Salpeter amplitude (3BS) of the $B$-meson. This 3BS contains one heavy-quark field and two light fields (a light quark and a gluon). Our discussion is aimed at clarifying properties of the $B$-meson 3BS necessary to describe properly charm-loop contributions to the amplitudes of FCNC $B$-decays. We demonstrate that the dominant contribution of nonfactorizable charm to FCNC $B$-decay amplitude is given in the heavy-quark limit by a convolution of some hard kernel and the $B$-meson 3BS in a "double-collinear" light cone (LC) configuration: one of the light degrees of freedom $\phi(x)$, $x^2=0$, lies on the $(+)$-direction of the LC, whereas another light degree of freedom $\phi'(x')$, $x'^2=0$ lies on the $(-)$-direction. We show the emergence of new constraints on the distribution amplitudes which parametrize the 3BS in this double-collinear configuration.
|
2004.12305
|
Jiaxing Zhao
|
Jiaxing Zhao, Shuzhe Shi, Nu Xu, Pengfei Zhuang
|
Sequential hadronization in heavy ion collisions
|
Contribution to: Quark Matter 2019
| null |
10.1016/j.nuclphysa.2020.121898
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Heavy flavor supplies a chance to constrain and improve the hadronization
mechanism. We have established a sequential coalescence model with charm
conservation and applied it to the charmed hadron production in heavy ion
collisions. The charm conservation enhances the earlier hadron production and
suppresses the later production. This relative enhancement (suppression)
changes significantly the ratios between charmed hadrons in heavy ion
collisions.
|
[
{
"created": "Sun, 26 Apr 2020 08:11:26 GMT",
"version": "v1"
}
] |
2021-02-03
|
[
[
"Zhao",
"Jiaxing",
""
],
[
"Shi",
"Shuzhe",
""
],
[
"Xu",
"Nu",
""
],
[
"Zhuang",
"Pengfei",
""
]
] |
Heavy flavor supplies a chance to constrain and improve the hadronization mechanism. We have established a sequential coalescence model with charm conservation and applied it to the charmed hadron production in heavy ion collisions. The charm conservation enhances the earlier hadron production and suppresses the later production. This relative enhancement (suppression) changes significantly the ratios between charmed hadrons in heavy ion collisions.
|
hep-ph/0201238
|
Masahide Yamaguchi
|
Masahide Yamaguchi
|
Double Inflation in Supergravity and Primordial Black Holes Formation
|
10 pages, talk given at COSMO-01 Workshop, Rovaniemi, Finland, August
30 - September 4, 2001
| null | null | null |
hep-ph astro-ph
| null |
In this talk we propose a natural double inflation model in supergravity.
Chaotic inflation first takes place by virtue of the Nambu-Goldstone-like shift
symmetry. During chaotic inflation, an initial value of second inflation (new
inflation) is set, which is adequately far from the local maximum of the
potential due to the small linear term in the K\"ahler potential. Then,
primordial fluctuations within the present horizon scale may be produced during
both inflations. Primordial fluctuations responsible for anisotropies of the
cosmic microwave background radiation and the large scale structure are
produced during chaotic inflation, while fluctuations on smaller scales are
produced during new inflation. Because of the peculiar nature of new inflation,
they can become as large as $10^{-1}$-$10^{-2}$, which may lead to the
formation of primordial black holes.
|
[
{
"created": "Fri, 25 Jan 2002 03:16:08 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Yamaguchi",
"Masahide",
""
]
] |
In this talk we propose a natural double inflation model in supergravity. Chaotic inflation first takes place by virtue of the Nambu-Goldstone-like shift symmetry. During chaotic inflation, an initial value of second inflation (new inflation) is set, which is adequately far from the local maximum of the potential due to the small linear term in the K\"ahler potential. Then, primordial fluctuations within the present horizon scale may be produced during both inflations. Primordial fluctuations responsible for anisotropies of the cosmic microwave background radiation and the large scale structure are produced during chaotic inflation, while fluctuations on smaller scales are produced during new inflation. Because of the peculiar nature of new inflation, they can become as large as $10^{-1}$-$10^{-2}$, which may lead to the formation of primordial black holes.
|
hep-ph/9502210
| null |
Dae-Gyu Lee and R. N. Mohapatra
|
Intermediate Scales in SUSY SO(10), b-\tau unification and Hot Dark
Matter Neutrinos
|
Latex file; 20 pages; Four figures available on request
|
Phys.Rev.D52:4125-4132,1995
|
10.1103/PhysRevD.52.4125
| null |
hep-ph
| null |
Considerations of massive neutrinos, baryogenesis as well as fermion mass
textures in the grand unified theory framework provide strong motivations for
supersymmetric(SUSY) SO(10) as the theory beyond the standard model. If one
wants to simultaneously solve the strong CP problem via the Peccei-Quinn
mechanism, the most natural way to implement it within the framework of the
SUSY SO(10) model is to have an intermediate scale ($v_{BL}$) (corresponding to
B-L symmetry breaking) around the invisible axion scale of about 10$^{11}$ -
10$^{12}$ GeV. Such a scale is also desirable if $\nu_{\tau}$ is to constitute
the hot dark matter (HDM) of the universe. In this paper, we discuss examples
of superstring inspired SUSY SO(10) models with intermediate scales that are
consistent with the low energy precision measurements of the standard model
gauge couplings. The hypothesis of $b-\tau$ unification which is a successful
prediction of many grand unified theories is then required of these models and
the resulting prediction of $b$-quark mass is used as a measure of viability of
these schemes. Detailed analysis of a model with a $v_{BL}\simeq 10^{11}$ GeV,
which satisfies both the requirements of invisible axion and $\nu_{\tau}$ as
HDM is presented and shown to lead to $m_b\simeq 4.9$ GeV in the one-loop
approximation.
|
[
{
"created": "Wed, 1 Feb 1995 18:44:06 GMT",
"version": "v1"
}
] |
2011-01-27
|
[
[
"Lee",
"Dae-Gyu",
""
],
[
"Mohapatra",
"R. N.",
""
]
] |
Considerations of massive neutrinos, baryogenesis as well as fermion mass textures in the grand unified theory framework provide strong motivations for supersymmetric(SUSY) SO(10) as the theory beyond the standard model. If one wants to simultaneously solve the strong CP problem via the Peccei-Quinn mechanism, the most natural way to implement it within the framework of the SUSY SO(10) model is to have an intermediate scale ($v_{BL}$) (corresponding to B-L symmetry breaking) around the invisible axion scale of about 10$^{11}$ - 10$^{12}$ GeV. Such a scale is also desirable if $\nu_{\tau}$ is to constitute the hot dark matter (HDM) of the universe. In this paper, we discuss examples of superstring inspired SUSY SO(10) models with intermediate scales that are consistent with the low energy precision measurements of the standard model gauge couplings. The hypothesis of $b-\tau$ unification which is a successful prediction of many grand unified theories is then required of these models and the resulting prediction of $b$-quark mass is used as a measure of viability of these schemes. Detailed analysis of a model with a $v_{BL}\simeq 10^{11}$ GeV, which satisfies both the requirements of invisible axion and $\nu_{\tau}$ as HDM is presented and shown to lead to $m_b\simeq 4.9$ GeV in the one-loop approximation.
|
hep-ph/0406213
|
Wei Zhu
|
Wei Zhu and Zhenqi Shen
|
Properties of the gluon recombination functions
|
18 pages, 6 figures. Corrections to Tables 1 and 2. Conclusions
unchanged
|
HEP. & NP. Vol.29,No.2(2005),109-114
| null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The gluon recombination functions in the twist-4 QCD evolution equations are
studied at the leading logarithmic approximation using both the covariant and
non-covariant methods. We justify that the infrared singularities in the
twist-4 coefficient functions impede us to simply separate the QCD evolution
kernels from the coefficient functions at the equivalent particle
approximation. In particulary, we point out that the gluon recombination
functions in the GLR-MQ evolution equation are unavailable. The methods
avoiding the IR divergences are discussed, which can be used in the derivations
of the evolution kernels and coefficient functions at the higher twist level.
|
[
{
"created": "Mon, 21 Jun 2004 04:11:25 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Mar 2005 11:47:59 GMT",
"version": "v2"
},
{
"created": "Sun, 29 Sep 2013 01:26:16 GMT",
"version": "v3"
}
] |
2013-10-01
|
[
[
"Zhu",
"Wei",
""
],
[
"Shen",
"Zhenqi",
""
]
] |
The gluon recombination functions in the twist-4 QCD evolution equations are studied at the leading logarithmic approximation using both the covariant and non-covariant methods. We justify that the infrared singularities in the twist-4 coefficient functions impede us to simply separate the QCD evolution kernels from the coefficient functions at the equivalent particle approximation. In particulary, we point out that the gluon recombination functions in the GLR-MQ evolution equation are unavailable. The methods avoiding the IR divergences are discussed, which can be used in the derivations of the evolution kernels and coefficient functions at the higher twist level.
|
0912.1218
|
Nobuhiro Uekusa
|
Nobuhiro Uekusa
|
Forward-backward asymmetry on Z resonance in SO(5) x U(1) gauge-Higgs
unification
|
26 pages, Analysis for other electroweak quantities is added
| null | null |
OU-HET 651/2009
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We find that the tree-level predictions of the forward-backward production
asymmetries on the Z resonance for b and c quarks, A_FB, in an SO(5) x U(1)
gauge-Higgs unification model are markedly close to the central values of the
Particle Data Group data unlike the standard model. The decay width of Z boson
is evaluated and the S and T parameters are discussed.
|
[
{
"created": "Mon, 7 Dec 2009 12:39:35 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Jul 2010 06:12:01 GMT",
"version": "v2"
}
] |
2010-07-30
|
[
[
"Uekusa",
"Nobuhiro",
""
]
] |
We find that the tree-level predictions of the forward-backward production asymmetries on the Z resonance for b and c quarks, A_FB, in an SO(5) x U(1) gauge-Higgs unification model are markedly close to the central values of the Particle Data Group data unlike the standard model. The decay width of Z boson is evaluated and the S and T parameters are discussed.
|
0809.4327
|
A. H. Rezaeian
|
B. Z. Kopeliovich, A. H. Rezaeian, Ivan Schmidt
|
Azimuthal Asymmetry of pions in pp and pA collisions
|
17 pages, 11 figures, minor typos corrected, references added. The
version to appear in Phys. Rev. D
|
Phys.Rev.D78:114009,2008
|
10.1103/PhysRevD.78.114009
| null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate the azimuthal asymmetry v2 of produced pions in pp and pA
collisions at both RHIC and SPS energies. In our approach, based on the pQCD
parton model and the light-cone QCD-dipole formalism, the azimuthal asymmetry
results from a correlation between the color-dipole orientation and the impact
parameter of the collision. We introduce the color-dipole orientation within an
improved Born approximation and the saturation model which satisfies available
DIS data, showing that the azimuthal asymmetry of partons and pions is very
sensitive to the choice of the model, and that it is reduced in the saturation
model. We find that v2 of quarks and gluons in parton-nucleus collisions have
very different patterns. The azimuthal asymmetry of gluons in gluon-nucleus
collisions can be negative at small transverse momentum, changes the sign and
becomes positive at high transverse momentum. The azimuthal asymmetry of quarks
in quark-nucleus collisions is positive at all values of transverse momentum.
We find that the azimuthal anisotropy v2 of produced pions in both pp and pA
collisions is positive, albeit rather small.
|
[
{
"created": "Thu, 25 Sep 2008 16:06:27 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Nov 2008 14:45:00 GMT",
"version": "v2"
}
] |
2008-12-30
|
[
[
"Kopeliovich",
"B. Z.",
""
],
[
"Rezaeian",
"A. H.",
""
],
[
"Schmidt",
"Ivan",
""
]
] |
We investigate the azimuthal asymmetry v2 of produced pions in pp and pA collisions at both RHIC and SPS energies. In our approach, based on the pQCD parton model and the light-cone QCD-dipole formalism, the azimuthal asymmetry results from a correlation between the color-dipole orientation and the impact parameter of the collision. We introduce the color-dipole orientation within an improved Born approximation and the saturation model which satisfies available DIS data, showing that the azimuthal asymmetry of partons and pions is very sensitive to the choice of the model, and that it is reduced in the saturation model. We find that v2 of quarks and gluons in parton-nucleus collisions have very different patterns. The azimuthal asymmetry of gluons in gluon-nucleus collisions can be negative at small transverse momentum, changes the sign and becomes positive at high transverse momentum. The azimuthal asymmetry of quarks in quark-nucleus collisions is positive at all values of transverse momentum. We find that the azimuthal anisotropy v2 of produced pions in both pp and pA collisions is positive, albeit rather small.
|
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