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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1010.3301
|
Daniel Seipt
|
D. Seipt and B. Kampfer
|
Non-Linear Compton Scattering of Ultrashort and Ultraintense Laser
Pulses
|
31 pages, 10 figures
|
Phys.Rev.A83:022101,2011
|
10.1103/PhysRevA.83.022101
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The scattering of temporally shaped intense laser pulses off electrons is
discussed by means of manifestly covariant quantum electrodynamics. We employ a
framework based on Volkov states with a time dependent laser envelope in
light-cone coordinates within the Furry picture. An expression for the cross
section is constructed, which is independent of the considered pulse shape and
pulse length. A broad distribution of scatted photons with a rich pattern of
subpeaks like that obtained in Thomson scattering is found. These broad peaks
may overlap at sufficiently high laser intensity, rendering inappropriate the
notion of individual harmonics. The limit of monochromatic plane waves as well
as the classical limit of Thomson scattering are discussed. As a main result, a
scaling law is presented connecting the Thomson limit with the general result
for arbitrary kinematics. In the overlapping regions of the spectral density,
the classical and quantum calculations give different results, even in the
Thomson limit. Thus, a phase space region is identified where the differential
photon distribution is strongly modified by quantum effects.
|
[
{
"created": "Sat, 16 Oct 2010 00:40:08 GMT",
"version": "v1"
}
] |
2011-06-21
|
[
[
"Seipt",
"D.",
""
],
[
"Kampfer",
"B.",
""
]
] |
The scattering of temporally shaped intense laser pulses off electrons is discussed by means of manifestly covariant quantum electrodynamics. We employ a framework based on Volkov states with a time dependent laser envelope in light-cone coordinates within the Furry picture. An expression for the cross section is constructed, which is independent of the considered pulse shape and pulse length. A broad distribution of scatted photons with a rich pattern of subpeaks like that obtained in Thomson scattering is found. These broad peaks may overlap at sufficiently high laser intensity, rendering inappropriate the notion of individual harmonics. The limit of monochromatic plane waves as well as the classical limit of Thomson scattering are discussed. As a main result, a scaling law is presented connecting the Thomson limit with the general result for arbitrary kinematics. In the overlapping regions of the spectral density, the classical and quantum calculations give different results, even in the Thomson limit. Thus, a phase space region is identified where the differential photon distribution is strongly modified by quantum effects.
|
1603.09031
|
Ahmed Rashed Dr
|
Ahmed Rashed and Alakabha Datta
|
Determination of mass hierarchy with $\nu_\mu \to \nu_\tau$ appearance
and the effect of nonstandard interactions
|
14 pages and 20 figures
|
Int. J. Mod. Phys. A 32, 1750060 (2017)
|
10.1142/S0217751X17500609
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Crucial developments in neutrino physics would be the determination of the
mass hierarchy (MH) and measurement of the CP phase in the leptonic sector. The
patterns of the transition probabilities $P(\nu_\mu \rightarrow \nu_\tau)$ and
$P(\bar{\nu}_\mu \rightarrow \bar{\nu}_\tau)$ are sensitive to these
oscillation parameters. An asymmetry parameter can be defined as the difference
of these two probabilities normalized to their sum. The profile of the
asymmetry parameter gives a clear signal of the mass ordering as it is found to
be positive for inverted hierarchy and negative for normal hierarchy. The
asymmetry parameter is also sensitive to the CP phase. We consider the effects
of non-standard neutrino interactions (NSI) on the determination of the mass
hierarchy. Since we assume the largest new physics effects involve the $\tau$
sector only, we ignore NSI in production and study the NSI effects in detection
as well as along propagation. We find that the NSI effects can significantly
modify the prediction of the asymmetry parameter though the MH can still be
resolved.
|
[
{
"created": "Wed, 30 Mar 2016 03:50:35 GMT",
"version": "v1"
}
] |
2017-04-27
|
[
[
"Rashed",
"Ahmed",
""
],
[
"Datta",
"Alakabha",
""
]
] |
Crucial developments in neutrino physics would be the determination of the mass hierarchy (MH) and measurement of the CP phase in the leptonic sector. The patterns of the transition probabilities $P(\nu_\mu \rightarrow \nu_\tau)$ and $P(\bar{\nu}_\mu \rightarrow \bar{\nu}_\tau)$ are sensitive to these oscillation parameters. An asymmetry parameter can be defined as the difference of these two probabilities normalized to their sum. The profile of the asymmetry parameter gives a clear signal of the mass ordering as it is found to be positive for inverted hierarchy and negative for normal hierarchy. The asymmetry parameter is also sensitive to the CP phase. We consider the effects of non-standard neutrino interactions (NSI) on the determination of the mass hierarchy. Since we assume the largest new physics effects involve the $\tau$ sector only, we ignore NSI in production and study the NSI effects in detection as well as along propagation. We find that the NSI effects can significantly modify the prediction of the asymmetry parameter though the MH can still be resolved.
|
hep-ph/9802311
|
Tanmay Vachaspati
|
Tanmay Vachaspati
|
Topological Defects in the Cosmos and Lab
|
13 pages, 9 figures; a reference corrected and a sentence clarified
|
Contemp.Phys. 39 (1998) 225-237
|
10.1080/001075198181928
|
CWRU-P10-98
|
hep-ph astro-ph cond-mat hep-th
| null |
Current theories of particle physics lead to the unavoidable conclusion that
there must have been several phase transitions in the early universe. Further,
in the context of these theories, it is possible that cosmological phase
transitions would have produced topological defects that may be roaming our
heavens today. A finding of these fossils from the early universe would provide
a direct confirmation of the thermal history of the cosmos, insight into
astrophysical phenomena, and, vital information about particle physics. The
elimination of unobserved topological defects provides important constraints on
particle physics and may also suggest novel cosmology. I describe some of the
research on cosmic topological defects and recent efforts to address
cosmological issues in condensed matter systems. (Invited article for
publication in Contemporary Physics.)
|
[
{
"created": "Thu, 12 Feb 1998 16:46:17 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Feb 1998 21:36:03 GMT",
"version": "v2"
}
] |
2009-10-31
|
[
[
"Vachaspati",
"Tanmay",
""
]
] |
Current theories of particle physics lead to the unavoidable conclusion that there must have been several phase transitions in the early universe. Further, in the context of these theories, it is possible that cosmological phase transitions would have produced topological defects that may be roaming our heavens today. A finding of these fossils from the early universe would provide a direct confirmation of the thermal history of the cosmos, insight into astrophysical phenomena, and, vital information about particle physics. The elimination of unobserved topological defects provides important constraints on particle physics and may also suggest novel cosmology. I describe some of the research on cosmic topological defects and recent efforts to address cosmological issues in condensed matter systems. (Invited article for publication in Contemporary Physics.)
|
hep-ph/9708290
| null |
N. N. Nikolaev (1,2), J.Speth (1), B. G. Zakharov (2). ((1)
IKP,KFA-Juelich, (2) Landau Inst., Moscow)
|
Absorptive corrections to the one pion exchange and measurablity of the
small-x pion structure function at HERA
|
15 pages, LaTeX, including 15 eps-figures
| null | null |
KFA-IKP(TH)-1997-17
|
hep-ph
| null |
We compaWe compare the absorptive corrections to the one pion exchange in
$pp\to Xn$ and $ep\to e'Xn$ reactions. It is shown that the absorption is
stronger in the case of $pp$ collision. The difference in strength of the
absorption for the $pp\to Xn$ and $ep\to e'Xn$ reactions breaks the
factorization peculiar to the pure one pion exchange. We evaluate the emerging
model dependence of extraction of the small-$x$ pion structure function from an
analysis of the HERA data on the neutron production at physical values of $t$.
|
[
{
"created": "Fri, 8 Aug 1997 16:20:55 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Nikolaev",
"N. N.",
""
],
[
"Speth",
"J.",
""
],
[
"Zakharov",
"B. G.",
""
],
[
".",
"",
""
]
] |
We compaWe compare the absorptive corrections to the one pion exchange in $pp\to Xn$ and $ep\to e'Xn$ reactions. It is shown that the absorption is stronger in the case of $pp$ collision. The difference in strength of the absorption for the $pp\to Xn$ and $ep\to e'Xn$ reactions breaks the factorization peculiar to the pure one pion exchange. We evaluate the emerging model dependence of extraction of the small-$x$ pion structure function from an analysis of the HERA data on the neutron production at physical values of $t$.
|
hep-ph/9807370
|
Massimo Blasone
|
Massimo Blasone, Peter A. Henning, Giuseppe Vitiello
|
Green's Functions for Neutrino Mixing
|
4 pages, LaTeX (need sprocl.sty). To appear in the Proceedings of the
6th International Symposium on Particles, Strings and Cosmology (PASCOS 98),
Boston, 22-27 March 1998
| null | null | null |
hep-ph
| null |
The Green's function formalism for neutrino mixing is presented and the exact
oscillation formula is obtained. The usual Pontecorvo formula is recovered in
the relativistic limit.
|
[
{
"created": "Tue, 14 Jul 1998 16:35:37 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Blasone",
"Massimo",
""
],
[
"Henning",
"Peter A.",
""
],
[
"Vitiello",
"Giuseppe",
""
]
] |
The Green's function formalism for neutrino mixing is presented and the exact oscillation formula is obtained. The usual Pontecorvo formula is recovered in the relativistic limit.
|
hep-ph/0001082
|
Raul Horvat
|
R. Horvat
|
Propagation of ultrahigh-energy neutrinos through the Earth
|
8 pages, some comments and references added, to appear in Phys. Lett.
B
|
Phys.Lett.B480:135-139,2000
|
10.1016/S0370-2693(00)00376-2
|
IRB-ZEF-2000/33
|
hep-ph
| null |
The dispersion relation in matter of ultrahigh-energy neutrinos above the
pole of the $W$ resonance ($E_{\nu} \gsim {\rm 10}^{7} {\rm GeV} $), is
studied. We perform our calculation using the real-time formulation of Thermal
Field Theory in which the massless limit for the $W$ boson is taken. The range
of active-to-sterile neutrino oscillation parameters for which there is
significant mixing enhancement during propagation through the interior of the
Earth, and therefore significant attenuation of neutrino beams in the Earth at
high energies, is estimated. Finally, this range is considered in view of the
cosmological and astrophysical constraints.
|
[
{
"created": "Tue, 11 Jan 2000 10:46:10 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Mar 2000 11:11:38 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Horvat",
"R.",
""
]
] |
The dispersion relation in matter of ultrahigh-energy neutrinos above the pole of the $W$ resonance ($E_{\nu} \gsim {\rm 10}^{7} {\rm GeV} $), is studied. We perform our calculation using the real-time formulation of Thermal Field Theory in which the massless limit for the $W$ boson is taken. The range of active-to-sterile neutrino oscillation parameters for which there is significant mixing enhancement during propagation through the interior of the Earth, and therefore significant attenuation of neutrino beams in the Earth at high energies, is estimated. Finally, this range is considered in view of the cosmological and astrophysical constraints.
|
hep-ph/0109279
|
B. F. L. Ward
|
S. Jadach (1 and 2), M. Melles (3), B.F.L. Ward (4 and 5) and S.A.
Yost (5) ((1) Institute of Nuclear Physics, Cracow, Poland, (2) CERN, Geneva,
Switzerland, (3) Paul-Scherrer-Institut, Wurenlingen und Villigen,
Switzerland, (4) Werner-Heisenberg-Institut, Max-Planck-Insitut fur Phyzik,
Germany, (5) Department of Physics and Astronomy, University of Tennessee,
Knoxville, TN, USA)
|
Exact Differential O(alpha**2) Results for Hard Bremsstrahlung in e+e-
Annihilation to 2f At and Beyond LEP2 Energies
|
26 pages, 5 figs.;improved discussion, figs. and
definitions;corrected misprints
|
Phys.Rev. D65 (2002) 073030
|
10.1103/PhysRevD.65.073030
|
UTHEP-01-0701, MPI-PhT-2001-22
|
hep-ph
| null |
We present the exact O(alpha) correction to the process e+ e- -> f f-bar +
gamma, f neq e, for ISR oplus FSR at and beyond LEP2 energies. We give explicit
formulas for the completely differential cross section. As an important
application, we compute the size of the respective sub-leading corrections of
O(alpha L) to the f f-bar cross section, where L is the respective big
logarithm in the renormalization group sense so that it is identifiable as L =
ln |s|/m_e^2 when s is the squared e+e- cms energy. Comparisons are made with
the available literature. We show explicitly that our results have the correct
infrared limit, as a cross-check. Some comments are made about the
implementation of our results in the framework of the Monte Carlo event
generator KK MC.
|
[
{
"created": "Fri, 28 Sep 2001 19:59:36 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Nov 2001 10:29:31 GMT",
"version": "v2"
},
{
"created": "Wed, 9 Jan 2002 10:51:02 GMT",
"version": "v3"
}
] |
2009-11-07
|
[
[
"Jadach",
"S.",
"",
"1 and 2"
],
[
"Melles",
"M.",
"",
"4 and 5"
],
[
"Ward",
"B. F. L.",
"",
"4 and 5"
],
[
"Yost",
"S. A.",
""
]
] |
We present the exact O(alpha) correction to the process e+ e- -> f f-bar + gamma, f neq e, for ISR oplus FSR at and beyond LEP2 energies. We give explicit formulas for the completely differential cross section. As an important application, we compute the size of the respective sub-leading corrections of O(alpha L) to the f f-bar cross section, where L is the respective big logarithm in the renormalization group sense so that it is identifiable as L = ln |s|/m_e^2 when s is the squared e+e- cms energy. Comparisons are made with the available literature. We show explicitly that our results have the correct infrared limit, as a cross-check. Some comments are made about the implementation of our results in the framework of the Monte Carlo event generator KK MC.
|
hep-ph/0509255
|
A. Yu. Ignatiev
|
A.Yu.Ignatiev and B.J.Carson
|
Evolving Fundamental Constants and Metrology
|
5 pages, RevTeX4, presented at the 16th National Congress of the
Australian Institute of Physics (Canberra, 31 January - 4 February 2005)
|
Proceedings of the 16th National Congress of the Australian
Institute of Physics (Canberra, 31 January - 4 February 2005), p.164-166
| null | null |
hep-ph astro-ph
| null |
Astrophysical observations suggest that the fine structure constant (alpha)
may (or may not) be evolving over the cosmological time scale. This raises a
much debated question: is alpha variation due to the variation of the speed of
light (c), elementary electric charge (e), or the Planck constant (h)?
Previously, we proposed the metrological approach based on the analysis of
the relationships between the fundamental units (e.g. of the length and time)
and the fundamental constants. Our methodology allows one to find how each of
the fundamental constants e, c, h evolves in time and offers a new outlook for
this area. Here we give a brief outline of this approach and the main results
it produces.
|
[
{
"created": "Fri, 23 Sep 2005 11:12:11 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Ignatiev",
"A. Yu.",
""
],
[
"Carson",
"B. J.",
""
]
] |
Astrophysical observations suggest that the fine structure constant (alpha) may (or may not) be evolving over the cosmological time scale. This raises a much debated question: is alpha variation due to the variation of the speed of light (c), elementary electric charge (e), or the Planck constant (h)? Previously, we proposed the metrological approach based on the analysis of the relationships between the fundamental units (e.g. of the length and time) and the fundamental constants. Our methodology allows one to find how each of the fundamental constants e, c, h evolves in time and offers a new outlook for this area. Here we give a brief outline of this approach and the main results it produces.
|
hep-ph/0509273
|
Yadong Yang
|
Ya-Dong Yang, Rumin Wang, G.R.Lu
|
The puzzles in $B\to \pi\pi$ and $ \pi K$ decays: possible implications
for R-parity violating supersymmetry
|
24 pages, 6 figures and 5 tables. Text revised. Final version to
appear in PRD
|
Phys.Rev.D73:015003,2006
|
10.1103/PhysRevD.73.015003
| null |
hep-ph
| null |
Recent experiments suggest that certain data of $B \to \pi\pi,\pi K$ decays
are inconsistent with the standard model expectations. We try to explain the
discrepancies with R-parity violating suppersymmetry. By employing the QCD
factorization approach, we study these decays in the minimal supersymmetric
standard model with R-parity violation. We show that R-parity violation can
resolve the discrepancies in both $B \to \pi\pi$ and $B \to \pi K$ decays, and
find that in some regions of parameter spaces all these requirements, including
the CP averaged branching ratios and the direct CP asymmetries, can be
satisfied. Furthermore, we have derived stringent bounds on relevant R-parity
violating couplings from the latest experimental data, and some of these
constraints are stronger than the existing bounds.
|
[
{
"created": "Sun, 25 Sep 2005 16:53:25 GMT",
"version": "v1"
},
{
"created": "Sat, 31 Dec 2005 03:55:37 GMT",
"version": "v2"
}
] |
2014-11-18
|
[
[
"Yang",
"Ya-Dong",
""
],
[
"Wang",
"Rumin",
""
],
[
"Lu",
"G. R.",
""
]
] |
Recent experiments suggest that certain data of $B \to \pi\pi,\pi K$ decays are inconsistent with the standard model expectations. We try to explain the discrepancies with R-parity violating suppersymmetry. By employing the QCD factorization approach, we study these decays in the minimal supersymmetric standard model with R-parity violation. We show that R-parity violation can resolve the discrepancies in both $B \to \pi\pi$ and $B \to \pi K$ decays, and find that in some regions of parameter spaces all these requirements, including the CP averaged branching ratios and the direct CP asymmetries, can be satisfied. Furthermore, we have derived stringent bounds on relevant R-parity violating couplings from the latest experimental data, and some of these constraints are stronger than the existing bounds.
|
1310.5692
|
Li-Hua Song
|
Li-Hua Song, Na Liu and Chun-Gui Duan
|
Atomic mass dependence of hadron production in semi-inclusive deep
inelastic lepton-nucleus scattering
|
arXiv admin note: text overlap with arXiv:1310.5285
|
Chinese Physics C Vol. 37, No. 10 (2013) 104102
|
10.1088/1674-1137/37/10/104102
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Hadron production in lepton-nucleus deep inelastic scattering is studied in a
quark energy loss model. The leading-order computations for hadron multiplicity
ratios are presented and compared with the selected HERMES pions production
data with the quark hadronization occurring outside the nucleus by means of the
hadron formation time. It is found that the obtained energy loss per unit
length is $0.440 \pm 0.013$ GeV/fm for an outgoing quark by the global fit. It
is confirmed that the atomic mass number dependence of hadron attenuation is
theoretically and experimentally in good agreement with the $A^{2/3}$ power law
for quark hadronization occurring outside the nucleus.
|
[
{
"created": "Sun, 20 Oct 2013 01:03:41 GMT",
"version": "v1"
}
] |
2013-10-23
|
[
[
"Song",
"Li-Hua",
""
],
[
"Liu",
"Na",
""
],
[
"Duan",
"Chun-Gui",
""
]
] |
Hadron production in lepton-nucleus deep inelastic scattering is studied in a quark energy loss model. The leading-order computations for hadron multiplicity ratios are presented and compared with the selected HERMES pions production data with the quark hadronization occurring outside the nucleus by means of the hadron formation time. It is found that the obtained energy loss per unit length is $0.440 \pm 0.013$ GeV/fm for an outgoing quark by the global fit. It is confirmed that the atomic mass number dependence of hadron attenuation is theoretically and experimentally in good agreement with the $A^{2/3}$ power law for quark hadronization occurring outside the nucleus.
|
2204.13120
|
Benoit Laurent
|
Benoit Laurent and James M. Cline
|
First principles determination of bubble wall velocity
|
17 pages, 6 figures
| null |
10.1103/PhysRevD.106.023501
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The terminal wall velocity of a first-order phase transition bubble can be
calculated from a set of fluid equations describing the scalar fields and the
plasma's state. We rederive these equations from the energy-momentum tensor
conservation and the Boltzmann equation, without linearizing in the background
temperature and fluid velocity. The resulting equations have a finite solution
for any wall velocity. We propose a spectral method to integrate the Boltzmann
equation, which is simple, efficient and accurate. As an example, we apply this
new methodology to the singlet scalar extension of the standard model. We find
that all solutions are naturally categorized as deflagrations ($v_w\sim c_s$)
or ultrarelativistic detonations ($\gamma_w\gtrsim10$). Furthermore, the
contributions from out-of-equilibrium effects are, most of the time,
subdominant. Finally, we use these results to propose several approximation
schemes with increasing levels of complexity and accuracy. They can be used to
considerably simplify the methodology while correctly describing the
qualitative behavior of the bubble wall.
|
[
{
"created": "Wed, 27 Apr 2022 18:00:01 GMT",
"version": "v1"
}
] |
2022-07-13
|
[
[
"Laurent",
"Benoit",
""
],
[
"Cline",
"James M.",
""
]
] |
The terminal wall velocity of a first-order phase transition bubble can be calculated from a set of fluid equations describing the scalar fields and the plasma's state. We rederive these equations from the energy-momentum tensor conservation and the Boltzmann equation, without linearizing in the background temperature and fluid velocity. The resulting equations have a finite solution for any wall velocity. We propose a spectral method to integrate the Boltzmann equation, which is simple, efficient and accurate. As an example, we apply this new methodology to the singlet scalar extension of the standard model. We find that all solutions are naturally categorized as deflagrations ($v_w\sim c_s$) or ultrarelativistic detonations ($\gamma_w\gtrsim10$). Furthermore, the contributions from out-of-equilibrium effects are, most of the time, subdominant. Finally, we use these results to propose several approximation schemes with increasing levels of complexity and accuracy. They can be used to considerably simplify the methodology while correctly describing the qualitative behavior of the bubble wall.
|
1104.2319
|
Martin Kober
|
Martin Kober
|
Electroweak Theory with a Minimal Length
|
20 pages
|
Int.J.Mod.Phys.A26:4251-4285, 2011
|
10.1142/S0217751X11054413
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
According to the introduction of a minimal length to quantum field theory
which is directly related to a generalized uncertainty principle the
implementation of the gauge principle becomes much more intricated. It has been
shown in another paper how gauge theories have to be extended in general, if
there is assumed the existence of a minimal length. In this paper this
generalization of the description of gauge theories is applied to the case of
Yang-Mills theories with gauge group SU(N) to consider especially the
application to the electroweak theory as it appears in the standard model. The
modifications of the lepton-, Higgs- and gauge field sector of the extended
Lagrangian of the electroweak theory maintaining local gauge invariance under
$SU(2)_L\otimes U(1)_Y$ transformations are investigated. There appear
additional interaction terms between the leptons or the Higgs particle
respectively with the photon and the W- and Z-bosons as well as additional
self-interaction terms of these gauge bosons themselves. It is remarkable that
in the quark sector where the full gauge group of the standard model, $SU(3)_c
\otimes SU(2)_L\otimes U(1)_Y$, has to be considered there arise coupling terms
between the gluons und the W- and Z-bosons which means that the electroweak
theory is not separated from quantum chromodynamics anymore.
|
[
{
"created": "Wed, 13 Apr 2011 14:08:23 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Aug 2011 10:39:22 GMT",
"version": "v2"
}
] |
2011-09-29
|
[
[
"Kober",
"Martin",
""
]
] |
According to the introduction of a minimal length to quantum field theory which is directly related to a generalized uncertainty principle the implementation of the gauge principle becomes much more intricated. It has been shown in another paper how gauge theories have to be extended in general, if there is assumed the existence of a minimal length. In this paper this generalization of the description of gauge theories is applied to the case of Yang-Mills theories with gauge group SU(N) to consider especially the application to the electroweak theory as it appears in the standard model. The modifications of the lepton-, Higgs- and gauge field sector of the extended Lagrangian of the electroweak theory maintaining local gauge invariance under $SU(2)_L\otimes U(1)_Y$ transformations are investigated. There appear additional interaction terms between the leptons or the Higgs particle respectively with the photon and the W- and Z-bosons as well as additional self-interaction terms of these gauge bosons themselves. It is remarkable that in the quark sector where the full gauge group of the standard model, $SU(3)_c \otimes SU(2)_L\otimes U(1)_Y$, has to be considered there arise coupling terms between the gluons und the W- and Z-bosons which means that the electroweak theory is not separated from quantum chromodynamics anymore.
|
hep-ph/9711243
|
Rainer Sommer
|
Rainer Sommer (DESY-IfH)
|
Non-perturbative renormalization of QCD
|
49 pages, lectures at Schladming-97
| null |
10.1007/BFb0106893
|
DESY 97-207
|
hep-ph hep-lat
| null |
In these lectures, we discuss different types of renormalization problems in
QCD and their non-perturbative solution in the framework of the lattice
formulation. In particular the recursive finite size methods to compute the
scale-dependence of renormalized quantities is explained. An important
ingredient in the practical applications is the Schr\"odinger functional. It is
introduced and its renormalization properties are discussed.
Concerning applications, the computation of the running coupling and the
running quark mass are covered in detail and it is shown how the
$\Lambda$-parameter and renormalization group invariant quark mass can be
obtained. Further topics are the renormalization of isovector currents and
non-perturbative Symanzik improvement.
|
[
{
"created": "Wed, 5 Nov 1997 17:55:28 GMT",
"version": "v1"
}
] |
2009-10-30
|
[
[
"Sommer",
"Rainer",
"",
"DESY-IfH"
]
] |
In these lectures, we discuss different types of renormalization problems in QCD and their non-perturbative solution in the framework of the lattice formulation. In particular the recursive finite size methods to compute the scale-dependence of renormalized quantities is explained. An important ingredient in the practical applications is the Schr\"odinger functional. It is introduced and its renormalization properties are discussed. Concerning applications, the computation of the running coupling and the running quark mass are covered in detail and it is shown how the $\Lambda$-parameter and renormalization group invariant quark mass can be obtained. Further topics are the renormalization of isovector currents and non-perturbative Symanzik improvement.
|
0910.4876
|
Martin Bauer
|
Martin Bauer
|
Randall-Sundrum Models and Precision Observables
|
Presented at the FLAVIAnet workshop in Kazimierz: Low energy
constraints on extensions of the Standard Model
|
Acta Phys.Polon.Supp.3:131-138,2010
| null |
MZ-TH/09-37
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
I present a review of phenomenological implications of the Randall-Sundrum
(RS) model with bulk fermions and brane-localized Higgs boson. Modifications to
the W-boson mass, corrections to the Peskin-Takeuchi parameters and to the Z ->
bb couplings will be discussed. From these observables severe bounds on the
mass scale of Kaluza-Klein (KK) modes arise. Constraints from all three
observables are very sensitive to the exact value of the Higgs boson mass and
the bounds can be significantly lowered by allowing for a heavy Higgs boson
(m_h ~ 1 TeV). Consequences thereof, as well as other approaches like "little
RS" models and models with custodial symmetry will also be briefly discussed.
|
[
{
"created": "Mon, 26 Oct 2009 13:38:57 GMT",
"version": "v1"
}
] |
2010-11-02
|
[
[
"Bauer",
"Martin",
""
]
] |
I present a review of phenomenological implications of the Randall-Sundrum (RS) model with bulk fermions and brane-localized Higgs boson. Modifications to the W-boson mass, corrections to the Peskin-Takeuchi parameters and to the Z -> bb couplings will be discussed. From these observables severe bounds on the mass scale of Kaluza-Klein (KK) modes arise. Constraints from all three observables are very sensitive to the exact value of the Higgs boson mass and the bounds can be significantly lowered by allowing for a heavy Higgs boson (m_h ~ 1 TeV). Consequences thereof, as well as other approaches like "little RS" models and models with custodial symmetry will also be briefly discussed.
|
1906.10466
|
Stefan Vogl
|
G. Arcadi, C. D\"oring, C. Hasterok and S. Vogl
|
Inelastic dark matter nucleus scattering
|
28 pages, 8 figures, version accepted for publication in JCAP
| null |
10.1088/1475-7516/2019/12/053
| null |
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Direct detection experiments aim at the detection of dark matter in the form
of weakly interacting massive particles (WIMPs) by searching for signals from
elastic dark matter nucleus scattering. Additionally, inelastic scattering in
which the nucleus is excited is expected from nuclear physics and provides an
additional detectable signal. In the context of a low-energy effective field
theory we investigate the experimental reach to these inelastic transitions for
xenon-based detectors employing a dual-phase time projection chamber. We find
that once a dark matter signal is established, inelastic transitions enhance
the discovery reach and we show that they allow a better determination of the
underlying particle physics.
|
[
{
"created": "Tue, 25 Jun 2019 12:06:58 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Dec 2019 12:53:08 GMT",
"version": "v2"
}
] |
2020-01-08
|
[
[
"Arcadi",
"G.",
""
],
[
"Döring",
"C.",
""
],
[
"Hasterok",
"C.",
""
],
[
"Vogl",
"S.",
""
]
] |
Direct detection experiments aim at the detection of dark matter in the form of weakly interacting massive particles (WIMPs) by searching for signals from elastic dark matter nucleus scattering. Additionally, inelastic scattering in which the nucleus is excited is expected from nuclear physics and provides an additional detectable signal. In the context of a low-energy effective field theory we investigate the experimental reach to these inelastic transitions for xenon-based detectors employing a dual-phase time projection chamber. We find that once a dark matter signal is established, inelastic transitions enhance the discovery reach and we show that they allow a better determination of the underlying particle physics.
|
2212.05076
|
Rok Medves
|
Rok Medves, Alba Soto-Ontoso, Gregory Soyez
|
Lund multiplicity in QCD jets
|
37 pages, 9 figures
| null |
10.1007/JHEP04(2023)104
|
CERN-TH-2022-205, OUTP-22-13P
|
hep-ph
|
http://creativecommons.org/licenses/by/4.0/
|
We compute the average Lund multiplicity of high-energy QCD jets. This
extends an earlier calculation, done for event-wide multiplicity in $e^+e^-$
collisions [arxiv:2205.02861], to the large energy range available at the LHC.
Our calculation achieves next-to-next-to-double logarithmic (NNDL) accuracy.
Our results are split into a universal collinear piece, common to the $e^+e^-$
calculation, and a non-universal large-angle contribution. The latter amounts
to 10-15% of the total multiplicity. We provide accurate LHC predictions by
matching our resummed calculation to fixed-order NLO results and by
incorporating non-perturbative corrections via Monte Carlo simulations.
Including NNDL terms leads to a 50% reduction of the theoretical uncertainty,
with non-perturbative corrections remaining below 5% down to transverse
momentum scales of a few GeV. This proves the suitability of Lund
multiplicities for robust theory-to-data comparisons at the LHC.
|
[
{
"created": "Fri, 9 Dec 2022 19:00:02 GMT",
"version": "v1"
}
] |
2023-05-10
|
[
[
"Medves",
"Rok",
""
],
[
"Soto-Ontoso",
"Alba",
""
],
[
"Soyez",
"Gregory",
""
]
] |
We compute the average Lund multiplicity of high-energy QCD jets. This extends an earlier calculation, done for event-wide multiplicity in $e^+e^-$ collisions [arxiv:2205.02861], to the large energy range available at the LHC. Our calculation achieves next-to-next-to-double logarithmic (NNDL) accuracy. Our results are split into a universal collinear piece, common to the $e^+e^-$ calculation, and a non-universal large-angle contribution. The latter amounts to 10-15% of the total multiplicity. We provide accurate LHC predictions by matching our resummed calculation to fixed-order NLO results and by incorporating non-perturbative corrections via Monte Carlo simulations. Including NNDL terms leads to a 50% reduction of the theoretical uncertainty, with non-perturbative corrections remaining below 5% down to transverse momentum scales of a few GeV. This proves the suitability of Lund multiplicities for robust theory-to-data comparisons at the LHC.
|
2003.07862
|
Samuel Lane
|
Julien Baglio, Sally Dawson, Samuel Homiller, Samuel D. Lane, and Ian
M. Lewis
|
Validity of SMEFT studies of VH and VV Production at NLO
|
32 pages, 7 figures, 8 tables
|
Phys. Rev. D 101, 115004 (2020)
|
10.1103/PhysRevD.101.115004
|
CERN-TH-2020-042, YITP-SB-20-04
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The production of $W^{\pm}H$, $ZH$, $W^+W^-$, and $W^\pm Z$ pairs probes
non-Standard-Model interactions of quarks, gauge bosons, and the Higgs boson.
New effects can be parameterized in terms of an effective field theory (EFT)
where the Lagrangian is expanded in terms of higher-dimension operators
suppressed by increasing powers of a high scale $\Lambda$. We examine the
importance of including next-to-leading-order QCD corrections in global fits to
the coefficients of the EFT. The numerical implications on the fits due to
different approaches to enforcing the validity of the EFT are quantified. We
pay particular attention to the dependence of the fits on the expansion in
$1/\Lambda^2$ since the differences between results calculated at ${\cal
{O}}(1/\Lambda^2)$ and ${\cal{O}}(1/\Lambda^4)$ may give insight into the
possible significance of dimension-8 effects.
|
[
{
"created": "Tue, 17 Mar 2020 18:00:01 GMT",
"version": "v1"
}
] |
2020-08-31
|
[
[
"Baglio",
"Julien",
""
],
[
"Dawson",
"Sally",
""
],
[
"Homiller",
"Samuel",
""
],
[
"Lane",
"Samuel D.",
""
],
[
"Lewis",
"Ian M.",
""
]
] |
The production of $W^{\pm}H$, $ZH$, $W^+W^-$, and $W^\pm Z$ pairs probes non-Standard-Model interactions of quarks, gauge bosons, and the Higgs boson. New effects can be parameterized in terms of an effective field theory (EFT) where the Lagrangian is expanded in terms of higher-dimension operators suppressed by increasing powers of a high scale $\Lambda$. We examine the importance of including next-to-leading-order QCD corrections in global fits to the coefficients of the EFT. The numerical implications on the fits due to different approaches to enforcing the validity of the EFT are quantified. We pay particular attention to the dependence of the fits on the expansion in $1/\Lambda^2$ since the differences between results calculated at ${\cal {O}}(1/\Lambda^2)$ and ${\cal{O}}(1/\Lambda^4)$ may give insight into the possible significance of dimension-8 effects.
|
1908.08387
|
Bipin singh Koranga
|
Bipin Singh Koranga (Department of Physics, Kirori Mal college,
University of Delhi, India)
|
Neutrino Mass Spectrum for Co-Bimaximal Mixings from Quantum Gravity
|
10 pages. arXiv admin note: substantial text overlap with
arXiv:1006.5553, arXiv:0810.4394
|
Int. J. Modern Theo. Physics, 2019, 8(1)
| null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider non-renormalizable interaction term as a perturbation of the
conventional neutrino mass matrix. Quantum gravitational (Planck scale )effects
lead to an effective $SU(2)_L\times U(1)$ invariant dimension-5 Lagrangian
involving neutrino and Higgs fields,On symmetry breaking, this operator gives
rise to correction to the neutrino masses and mixing. The gravitational
interaction $M_X=M_{pl}$ which gives rise to additional terms in neutrino mass
matrix. We also assume that, just above the electroweak breaking scale,
neutrino masses are nearly degenerate and their mixing is Co-bimaximal mixing
by assuming mixing angle $\theta_{13}\neq0 = 10^{o}$,
$\theta_{23}=\frac{\pi}{4}$, $\tan\theta_{12}^ 2 =
\frac{1-3sin\theta_{13}^2}{2} = 34^{o}$ and Dirac phase
$\delta=\pm\frac{\pi}{2}$.There additional term can be considered to be
perturbation of the GUT scale Co-bimaximal neutrino mass matrix. The relation
consider with solar and atmospheric neutrino oscillation data predicted above
GUT scale $m_1' \simeq 0.00001eV-0.00003eV$, $m_2' \simeq 0.00008eV-0.00012$,
and $m_3' \simeq 0.000207eV-000320eV$.
|
[
{
"created": "Sun, 18 Aug 2019 07:57:27 GMT",
"version": "v1"
}
] |
2019-08-23
|
[
[
"Koranga",
"Bipin Singh",
"",
"Department of Physics, Kirori Mal college,\n University of Delhi, India"
]
] |
We consider non-renormalizable interaction term as a perturbation of the conventional neutrino mass matrix. Quantum gravitational (Planck scale )effects lead to an effective $SU(2)_L\times U(1)$ invariant dimension-5 Lagrangian involving neutrino and Higgs fields,On symmetry breaking, this operator gives rise to correction to the neutrino masses and mixing. The gravitational interaction $M_X=M_{pl}$ which gives rise to additional terms in neutrino mass matrix. We also assume that, just above the electroweak breaking scale, neutrino masses are nearly degenerate and their mixing is Co-bimaximal mixing by assuming mixing angle $\theta_{13}\neq0 = 10^{o}$, $\theta_{23}=\frac{\pi}{4}$, $\tan\theta_{12}^ 2 = \frac{1-3sin\theta_{13}^2}{2} = 34^{o}$ and Dirac phase $\delta=\pm\frac{\pi}{2}$.There additional term can be considered to be perturbation of the GUT scale Co-bimaximal neutrino mass matrix. The relation consider with solar and atmospheric neutrino oscillation data predicted above GUT scale $m_1' \simeq 0.00001eV-0.00003eV$, $m_2' \simeq 0.00008eV-0.00012$, and $m_3' \simeq 0.000207eV-000320eV$.
|
0912.0520
|
Dejan Stojkovic
|
De-Chang Dai, Arthur Lue, Glenn Starkman, and Dejan Stojkovic
|
Electroweak stars: how nature may capitalize on the standard model's
ultimate fuel
|
Version published in JCAP
|
JCAP 1012:004,2010
|
10.1088/1475-7516/2010/12/004
| null |
hep-ph astro-ph.CO gr-qc hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the possible existence of an electroweak star - a compact
stellar-mass object whose central core temperature is higher than the
electroweak symmetry restoration temperature. We found a solution to the
Tolman-Oppenheimer-Volkoff equations describing such an object. The parameters
of such a star are not substantially different from a neutron star - its mass
is around 1.3 Solar masses while its radius is around 8 km. What is different
is the existence of a small electroweak core. The source of energy in the core
that can at least temporarily balance gravity are standard-model
non-perturbative baryon number (B) and lepton number (L) violating processes
that allow the chemical potential of $B+L$ to relax to zero. The energy
released at the core is enormous, but gravitational redshift and the enhanced
neutrino interaction cross section at these energies make the energy release
rate moderate at the surface of the star. The lifetime of this new
quasi-equilibrium can be more than ten million years. This is long enough to
represent a new stage in the evolution of a star if stellar evolution can take
it there.
|
[
{
"created": "Wed, 2 Dec 2009 21:02:33 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Sep 2010 01:45:32 GMT",
"version": "v2"
},
{
"created": "Wed, 19 Jan 2011 21:03:03 GMT",
"version": "v3"
}
] |
2011-01-21
|
[
[
"Dai",
"De-Chang",
""
],
[
"Lue",
"Arthur",
""
],
[
"Starkman",
"Glenn",
""
],
[
"Stojkovic",
"Dejan",
""
]
] |
We study the possible existence of an electroweak star - a compact stellar-mass object whose central core temperature is higher than the electroweak symmetry restoration temperature. We found a solution to the Tolman-Oppenheimer-Volkoff equations describing such an object. The parameters of such a star are not substantially different from a neutron star - its mass is around 1.3 Solar masses while its radius is around 8 km. What is different is the existence of a small electroweak core. The source of energy in the core that can at least temporarily balance gravity are standard-model non-perturbative baryon number (B) and lepton number (L) violating processes that allow the chemical potential of $B+L$ to relax to zero. The energy released at the core is enormous, but gravitational redshift and the enhanced neutrino interaction cross section at these energies make the energy release rate moderate at the surface of the star. The lifetime of this new quasi-equilibrium can be more than ten million years. This is long enough to represent a new stage in the evolution of a star if stellar evolution can take it there.
|
hep-ph/0610146
|
Andr\'e Mota
|
A. L. Mota and E. Ruiz Arriola
|
Relativistic NJL Model with Light and Heavy Quarks
|
5 pages, 2 figures. Talk given at the IV International Conference on
Quarks and Nuclear Physics (QNP06), Madrid, June 5th - 10th 2006
|
Eur.Phys.J.A31:711-713,2007
|
10.1140/epja/i2006-10243-1
| null |
hep-ph
| null |
We study the Nambu-Jona-Lasinio model with light and heavy quarks in a
relativistic approach. We emphasize relevant regularization issues as well as
the transition from light to heavy quarks. The approach of the electromagnetic
meson form factor to the Isgur-Wise function in the heavy quark limit is also
discussed.
|
[
{
"created": "Wed, 11 Oct 2006 22:32:55 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Mota",
"A. L.",
""
],
[
"Arriola",
"E. Ruiz",
""
]
] |
We study the Nambu-Jona-Lasinio model with light and heavy quarks in a relativistic approach. We emphasize relevant regularization issues as well as the transition from light to heavy quarks. The approach of the electromagnetic meson form factor to the Isgur-Wise function in the heavy quark limit is also discussed.
|
hep-ph/9411442
|
German Valencia
|
G. Valencia (Iowa State University)
|
CP Violation in Hyperon Decays
|
Invited talk at HQ94, Oct. 7-10, 1994, Charlottesville, Virginia. 8
pages LaTeX
|
Frascati Phys.Ser.3:71-80,1994
| null |
AMES-HET-94-13
|
hep-ph
| null |
In this talk we review the status of the theoretical estimates for CP
violating asymmetries in non-leptonic hyperon decays.
|
[
{
"created": "Wed, 30 Nov 1994 17:00:03 GMT",
"version": "v1"
}
] |
2010-11-01
|
[
[
"Valencia",
"G.",
"",
"Iowa State University"
]
] |
In this talk we review the status of the theoretical estimates for CP violating asymmetries in non-leptonic hyperon decays.
|
1606.00916
|
David M. Straub
|
Thomas Blake, Gaia Lanfranchi and David M. Straub
|
Rare $B$ Decays as Tests of the Standard Model
|
59 pages, 16 figures. Invited review for "Progress in Particle and
Nuclear Physics". v2: matches published version
| null |
10.1016/j.ppnp.2016.10.001
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
One of the most interesting puzzles in particle physics today is that new
physics is expected at the TeV energy scale to solve the hierarchy problem, and
stabilise the Higgs mass, but so far no unambiguous signal of new physics has
been found. Strong constraints on the energy scale of new physics can be
derived from precision tests of the electroweak theory and from
flavour-changing or CP-violating processes in strange, charm and beauty hadron
decays. Decays that proceed via flavour-changing-neutral-current processes are
forbidden at the lowest perturbative order in the Standard Model and are,
therefore, rare. Rare $b$ hadron decays are playing a central role in the
understanding of the underlying patterns of Standard Model physics and in
setting up new directions in model building for new physics contributions. In
this article the status and prospects of this field are reviewed.
|
[
{
"created": "Thu, 2 Jun 2016 22:00:13 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Nov 2016 09:44:48 GMT",
"version": "v2"
}
] |
2017-01-04
|
[
[
"Blake",
"Thomas",
""
],
[
"Lanfranchi",
"Gaia",
""
],
[
"Straub",
"David M.",
""
]
] |
One of the most interesting puzzles in particle physics today is that new physics is expected at the TeV energy scale to solve the hierarchy problem, and stabilise the Higgs mass, but so far no unambiguous signal of new physics has been found. Strong constraints on the energy scale of new physics can be derived from precision tests of the electroweak theory and from flavour-changing or CP-violating processes in strange, charm and beauty hadron decays. Decays that proceed via flavour-changing-neutral-current processes are forbidden at the lowest perturbative order in the Standard Model and are, therefore, rare. Rare $b$ hadron decays are playing a central role in the understanding of the underlying patterns of Standard Model physics and in setting up new directions in model building for new physics contributions. In this article the status and prospects of this field are reviewed.
|
0802.2348
|
Itay Hen
|
Itay Hen, Marek Karliner
|
Spontaneous Breaking of Rotational Symmetry in Rotating Solitons - a Toy
Model of Excited Nucleons with High Angular Momentum
|
RevTex, 9 pages, 9 figures. Added content
|
Phys.Rev.D77:116002,2008
|
10.1103/PhysRevD.77.116002
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study the phenomenon of spontaneous breaking of rotational symmetry (SBRS)
in the rotating solutions of two types of baby Skyrme models. In the first the
domain is a two-sphere and in the other, the Skyrmions are confined to the
interior of a unit disk. Numerical full-field results show that when the
angular momentum of the Skyrmions increases above a certain critical value, the
rotational symmetry of the solutions is broken and the minimal energy
configurations become less symmetric. We propose a possible mechanism as to why
SBRS is present in the rotating solutions of these models, while it is not
observed in the `usual' baby Skyrme model. Our results might be relevant for a
qualitative understanding of the non-spherical deformation of excited nucleons
with high orbital angular momentum.
|
[
{
"created": "Sat, 16 Feb 2008 19:48:16 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Mar 2008 14:27:30 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Hen",
"Itay",
""
],
[
"Karliner",
"Marek",
""
]
] |
We study the phenomenon of spontaneous breaking of rotational symmetry (SBRS) in the rotating solutions of two types of baby Skyrme models. In the first the domain is a two-sphere and in the other, the Skyrmions are confined to the interior of a unit disk. Numerical full-field results show that when the angular momentum of the Skyrmions increases above a certain critical value, the rotational symmetry of the solutions is broken and the minimal energy configurations become less symmetric. We propose a possible mechanism as to why SBRS is present in the rotating solutions of these models, while it is not observed in the `usual' baby Skyrme model. Our results might be relevant for a qualitative understanding of the non-spherical deformation of excited nucleons with high orbital angular momentum.
|
1607.02050
|
Luca Panizzi
|
Sabine Kraml, Ursula Laa, Luca Panizzi, Hugo Prager
|
Scalar versus fermionic top partner interpretations of $t\bar t +
E_T^{\rm miss}$ searches at the LHC
|
39 pages, 8 figures, 17 tables. Version accepted by JHEP. Efficiency
maps derived for this paper can be downloaded from
http://lpsc.in2p3.fr/projects-th/recasting/susy-vs-vlq/ttbarMET
|
JHEP 11 (2016) 107
|
10.1007/JHEP11(2016)107
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We assess how different ATLAS and CMS searches for supersymmetry in the
$t\bar t + E_T^{\rm miss}$ final state at Run 1 of the LHC constrain scenarios
with a fermionic top partner and a dark matter candidate. We find that the
efficiencies of these searches in all-hadronic, 1-lepton and 2-lepton channels
are quite similar for scalar and fermionic top partners. Therefore, in general,
efficiency maps for stop-neutralino simplified models can also be applied to
fermionic top-partner models, provided the narrow width approximation holds in
the latter. Owing to the much higher production cross-sections of heavy top
quarks as compared to stops, masses up to $m_T\approx 850$ GeV can be excluded
from the Run 1 stop searches. Since the simplified-model results published by
ATLAS and CMS do not extend to such high masses, we provide our own efficiency
maps obtained with CheckMATE and MadAnalysis 5 for these searches. Finally, we
also discuss how generic gluino/squark searches in multi-jet final states
constrain heavy top partner production.
|
[
{
"created": "Thu, 7 Jul 2016 15:39:43 GMT",
"version": "v1"
},
{
"created": "Fri, 18 Nov 2016 09:13:43 GMT",
"version": "v2"
}
] |
2016-11-28
|
[
[
"Kraml",
"Sabine",
""
],
[
"Laa",
"Ursula",
""
],
[
"Panizzi",
"Luca",
""
],
[
"Prager",
"Hugo",
""
]
] |
We assess how different ATLAS and CMS searches for supersymmetry in the $t\bar t + E_T^{\rm miss}$ final state at Run 1 of the LHC constrain scenarios with a fermionic top partner and a dark matter candidate. We find that the efficiencies of these searches in all-hadronic, 1-lepton and 2-lepton channels are quite similar for scalar and fermionic top partners. Therefore, in general, efficiency maps for stop-neutralino simplified models can also be applied to fermionic top-partner models, provided the narrow width approximation holds in the latter. Owing to the much higher production cross-sections of heavy top quarks as compared to stops, masses up to $m_T\approx 850$ GeV can be excluded from the Run 1 stop searches. Since the simplified-model results published by ATLAS and CMS do not extend to such high masses, we provide our own efficiency maps obtained with CheckMATE and MadAnalysis 5 for these searches. Finally, we also discuss how generic gluino/squark searches in multi-jet final states constrain heavy top partner production.
|
1507.05028
|
Yuji Omura
|
Yuji Omura, Kazuhiro Tobe, Koji Tsumura
|
Survey of Higgs interpretations of the diboson excesses
|
14 pages, 7 figures
|
Phys. Rev. D 92, 055015 (2015)
|
10.1103/PhysRevD.92.055015
|
KUNS-2570
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigate diboson signals in the Standard Model (SM) with an extended
Higgs sector, motivated by the excesses in the diboson channels at the LHC. We
begin with the unitarity sum-rules of the weak gauge boson scattering assuming
the Higgs sector is extended. According to the sum-rules, we discuss the Higgs
interpretations of the diboson signals and the consistency with the ATLAS
diboson anomaly and other experimental constraints. As a concrete example, we
propose a two-Higgs-doublet model where the Yukawa coupling of an extra CP-even
scalar with up-type quark is relatively large. The diboson (WW and ZZ) signals
can be explained by 2 TeV CP-even Higgs boson, while the partners, the CP-odd
and the charged Higgs bosons in the extra doublet, are severely constrained by
both the LHC direct search and the indirect search via flavor observables.
Especially, in order to avoid the diboson resonance search in the Vh channel,
further extensions of the model are required. The diboson excess is correlated
with the SM Higgs signals in our framework, so that the precise measurement of
the SM Higgs boson is also important to test the Higgs interpretation.
|
[
{
"created": "Fri, 17 Jul 2015 16:43:27 GMT",
"version": "v1"
}
] |
2015-09-23
|
[
[
"Omura",
"Yuji",
""
],
[
"Tobe",
"Kazuhiro",
""
],
[
"Tsumura",
"Koji",
""
]
] |
We investigate diboson signals in the Standard Model (SM) with an extended Higgs sector, motivated by the excesses in the diboson channels at the LHC. We begin with the unitarity sum-rules of the weak gauge boson scattering assuming the Higgs sector is extended. According to the sum-rules, we discuss the Higgs interpretations of the diboson signals and the consistency with the ATLAS diboson anomaly and other experimental constraints. As a concrete example, we propose a two-Higgs-doublet model where the Yukawa coupling of an extra CP-even scalar with up-type quark is relatively large. The diboson (WW and ZZ) signals can be explained by 2 TeV CP-even Higgs boson, while the partners, the CP-odd and the charged Higgs bosons in the extra doublet, are severely constrained by both the LHC direct search and the indirect search via flavor observables. Especially, in order to avoid the diboson resonance search in the Vh channel, further extensions of the model are required. The diboson excess is correlated with the SM Higgs signals in our framework, so that the precise measurement of the SM Higgs boson is also important to test the Higgs interpretation.
|
hep-ph/0405045
|
Kirill Tuchin
|
Dmitri Kharzeev, Yuri V. Kovchegov, Kirill Tuchin
|
Nuclear Modification Factor in d+Au Collisions: Onset of Suppression in
the Color Glass Condensate
|
8 pages, 4 figures; results for negatively charged hadrons at forward
rapidities are added
|
Phys.Lett.B599:23-31,2004
|
10.1016/j.physletb.2004.08.034
|
BNL-NT-04/16, NT@UW-04-010
|
hep-ph nucl-ex nucl-th
| null |
We perform a quantitative analysis of the nuclear modification factor in
deuteron--gold collisions R(dAu) within the Color Glass Condensate approach,
and compare our results with the recent data from RHIC experiments. Our model
leads to Cronin enhancement at mid-rapidity, while at forward rapidities it
predicts strong suppression of R(dAu) at all pT due to low-x evolution. We
demonstrate that our results are consistent with the data for dAu charged
hadron spectra, R(dAu) and R(CP) recently reported for rapidities in the
interval eta=0--3.2 by the BRAHMS experiment at RHIC. We also make a prediction
for R(pA) at mid-rapidity in pA collisions at the LHC.
|
[
{
"created": "Thu, 6 May 2004 00:54:11 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Aug 2004 18:23:04 GMT",
"version": "v2"
}
] |
2011-01-25
|
[
[
"Kharzeev",
"Dmitri",
""
],
[
"Kovchegov",
"Yuri V.",
""
],
[
"Tuchin",
"Kirill",
""
]
] |
We perform a quantitative analysis of the nuclear modification factor in deuteron--gold collisions R(dAu) within the Color Glass Condensate approach, and compare our results with the recent data from RHIC experiments. Our model leads to Cronin enhancement at mid-rapidity, while at forward rapidities it predicts strong suppression of R(dAu) at all pT due to low-x evolution. We demonstrate that our results are consistent with the data for dAu charged hadron spectra, R(dAu) and R(CP) recently reported for rapidities in the interval eta=0--3.2 by the BRAHMS experiment at RHIC. We also make a prediction for R(pA) at mid-rapidity in pA collisions at the LHC.
|
hep-ph/0006170
|
Wally Melnitchouk
|
W. Melnitchouk
|
QCD and the Structure of the Nucleon in Electron Scattering
|
52 pages, 11 figures, lectures presented at the 1999 Hampton
University Graduate Studies (HUGS) summer school, Jefferson Lab
| null |
10.1142/9789812810205_0005
|
ADP-00-28/T414, JLAB-THY-00-18
|
hep-ph hep-ex nucl-ex nucl-th
| null |
The internal structure of the nucleon is discussed within the context of QCD.
Recent progress in understanding the distribution of flavor and spin in the
nucleon is reviewed, and prospects for extending our knowledge of nucleon
structure in electron scattering experiments at modern facilities such as
Jefferson Lab are outlined.
|
[
{
"created": "Thu, 15 Jun 2000 12:31:00 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Aug 2001 20:05:15 GMT",
"version": "v2"
}
] |
2017-08-23
|
[
[
"Melnitchouk",
"W.",
""
]
] |
The internal structure of the nucleon is discussed within the context of QCD. Recent progress in understanding the distribution of flavor and spin in the nucleon is reviewed, and prospects for extending our knowledge of nucleon structure in electron scattering experiments at modern facilities such as Jefferson Lab are outlined.
|
hep-ph/9712527
|
postDr.
|
B. Tseng and Hsiang-nan Li
|
Solution of $a_2/a_1$ sign problem in heavy meson decays:
nonfactorizable soft gluons in nonleptonic heavy meson decays
|
5 pages. talk given at the APCTP workshop: Pacific Particle physics
Phenomenology 31 Oct.-2 Nov.,1997,Seoul, Korea
| null | null | null |
hep-ph
| null |
For the first time, a solution to the $a_2/a_1$ sign problem in heavy meson
decay based on PQCD factorization theorems. The point is to include QCD
evolution effort characteristic scales involved in decay processes.
|
[
{
"created": "Fri, 26 Dec 1997 19:19:59 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Tseng",
"B.",
""
],
[
"Li",
"Hsiang-nan",
""
]
] |
For the first time, a solution to the $a_2/a_1$ sign problem in heavy meson decay based on PQCD factorization theorems. The point is to include QCD evolution effort characteristic scales involved in decay processes.
|
1111.4820
|
Altan Cakir
|
Altan Cakir
|
Searches for Supersymmetry with the CMS Experiment
|
6 pages, conference proceeding, 15th Lomonosov Conference for
Elementary Particle Physics, Moscow, Russia
| null | null | null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
After a very successful startup of the LHC in 2010, the CMS experiment has
already accumulated significantly more data in 2011. After the successful
re-discovery of the Standard Model, the search for signs of new physics has
already reached, and in most cases enlarged, the limits from previous
experiments. In this conference report I review the recent discovery reach of
SUSY searches that will be performed with the 2011 data.
|
[
{
"created": "Mon, 21 Nov 2011 10:37:33 GMT",
"version": "v1"
}
] |
2011-11-22
|
[
[
"Cakir",
"Altan",
""
]
] |
After a very successful startup of the LHC in 2010, the CMS experiment has already accumulated significantly more data in 2011. After the successful re-discovery of the Standard Model, the search for signs of new physics has already reached, and in most cases enlarged, the limits from previous experiments. In this conference report I review the recent discovery reach of SUSY searches that will be performed with the 2011 data.
|
hep-ph/0403254
|
Andrzej Bialas
|
A. Bialas and M. Jezabek
|
Bremsstrahlung from colour charges as a source of soft particle
production in hadronic collisions
|
11 pages, 2 figures
|
Phys.Lett. B590 (2004) 233-238
|
10.1016/j.physletb.2004.03.070
| null |
hep-ph
| null |
It is proposed that soft particle production in hadronic collisions is
dominated by multiple gluon exchanges between partons from the colliding
hadrons, followed by radiation of hadronic clusters from the coloured partons
distributed uniformly in rapidity. This explains naturally two dominant
features of the data: (a) The linear increase of rapidity spectra in the
regions of limiting fragmentation and, (b) the proportionality between the
increasing width of the limiting fragmentation region and the height of the
central plateau.
|
[
{
"created": "Wed, 24 Mar 2004 10:25:35 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Mar 2004 14:38:54 GMT",
"version": "v2"
}
] |
2009-11-10
|
[
[
"Bialas",
"A.",
""
],
[
"Jezabek",
"M.",
""
]
] |
It is proposed that soft particle production in hadronic collisions is dominated by multiple gluon exchanges between partons from the colliding hadrons, followed by radiation of hadronic clusters from the coloured partons distributed uniformly in rapidity. This explains naturally two dominant features of the data: (a) The linear increase of rapidity spectra in the regions of limiting fragmentation and, (b) the proportionality between the increasing width of the limiting fragmentation region and the height of the central plateau.
|
hep-ph/0403101
|
Raphael Micha
|
Raphael Micha and Igor I. Tkachev
|
Turbulent Thermalization
|
27 pages, 13 figures
|
Phys.Rev. D70 (2004) 043538
|
10.1103/PhysRevD.70.043538
| null |
hep-ph astro-ph hep-lat hep-th
| null |
We study, analytically and with lattice simulations, the decay of coherent
field oscillations and the subsequent thermalization of the resulting
stochastic classical wave-field. The problem of reheating of the Universe after
inflation constitutes our prime motivation and application of the results. We
identify three different stages of these processes. During the initial stage of
``parametric resonance'', only a small fraction of the initial inflaton energy
is transferred to fluctuations in the physically relevant case of sufficiently
large couplings. A major fraction is transfered in the prompt regime of driven
turbulence. The subsequent long stage of thermalization classifies as free
turbulence. During the turbulent stages, the evolution of particle distribution
functions is self-similar. We show that wave kinetic theory successfully
describes the late stages of our lattice calculation. Our analytical results
are general and give estimates of reheating time and temperature in terms of
coupling constants and initial inflaton amplitude.
|
[
{
"created": "Tue, 9 Mar 2004 14:58:54 GMT",
"version": "v1"
}
] |
2009-11-10
|
[
[
"Micha",
"Raphael",
""
],
[
"Tkachev",
"Igor I.",
""
]
] |
We study, analytically and with lattice simulations, the decay of coherent field oscillations and the subsequent thermalization of the resulting stochastic classical wave-field. The problem of reheating of the Universe after inflation constitutes our prime motivation and application of the results. We identify three different stages of these processes. During the initial stage of ``parametric resonance'', only a small fraction of the initial inflaton energy is transferred to fluctuations in the physically relevant case of sufficiently large couplings. A major fraction is transfered in the prompt regime of driven turbulence. The subsequent long stage of thermalization classifies as free turbulence. During the turbulent stages, the evolution of particle distribution functions is self-similar. We show that wave kinetic theory successfully describes the late stages of our lattice calculation. Our analytical results are general and give estimates of reheating time and temperature in terms of coupling constants and initial inflaton amplitude.
|
0710.3796
|
Ryuichiro Kitano
|
Masahiro Ibe, Ryuichiro Kitano
|
Sweet Spot Supersymmetry and Composite Messengers
|
12 pages
|
Phys.Lett.B663:242-246,2008
|
10.1016/j.physletb.2008.04.023
|
LA-UR-07-7067, SLAC-PUB-12893
|
hep-ph hep-th
| null |
Sweet spot supersymmetry is a phenomenologically and cosmologically perfect
framework to realize a supersymmetric world at short distance. We discuss a
class of dynamical models of supersymmetry breaking and its mediation whose
low-energy effective description falls into this framework. Hadron fields in
the dynamical models play a role of the messengers of the supersymmetry
breaking. As is always true in the models of the sweet spot supersymmetry, the
messenger scale is predicted to be 10^5 GeV < M_mess < 10^{10} GeV. Various
values of the effective number of messenger fields N_mess are possible
depending on the choice of the gauge group.
|
[
{
"created": "Fri, 19 Oct 2007 22:40:34 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Ibe",
"Masahiro",
""
],
[
"Kitano",
"Ryuichiro",
""
]
] |
Sweet spot supersymmetry is a phenomenologically and cosmologically perfect framework to realize a supersymmetric world at short distance. We discuss a class of dynamical models of supersymmetry breaking and its mediation whose low-energy effective description falls into this framework. Hadron fields in the dynamical models play a role of the messengers of the supersymmetry breaking. As is always true in the models of the sweet spot supersymmetry, the messenger scale is predicted to be 10^5 GeV < M_mess < 10^{10} GeV. Various values of the effective number of messenger fields N_mess are possible depending on the choice of the gauge group.
|
1104.0367
|
Takashi Toma
|
Yuji Kajiyama, Hiroshi Okada and Takashi Toma
|
Direct and Indirect Detection of Dark Matter in D6 Flavor Symmetric
Model
|
20 pages, 9 figures, 2 tables, accepted version for publication in
European Physical Journal C
|
Eur.Phys.J. C71 (2011) 1688
|
10.1140/epjc/s10052-011-1688-0
|
KANAZAWA-11-08
|
hep-ph astro-ph.HE
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study a fermionic dark matter in a non-supersymmetric extension of the
standard model with a family symmetry based on D6xZ2xZ2. In our model, the
final state of the dark matter annihilation is determined to be e+ e- by the
flavor symmetry, which is consistent with the PAMELA result. At first, we show
that our dark matter mass should be within the range of 230 GeV - 750 GeV in
the WMAP analysis combined with mu to e gamma constraint. Moreover we
simultaneously explain the experiments of direct and indirect detection, by
simply adding a gauge and D6 singlet real scalar field. In the direct detection
experiments, we show that the lighter dark matter mass ~ 230 GeV and the
lighter standard model Higgs boson ~ 115 GeV is in favor of the observed bounds
reported by CDMS II and XENON100. In the indirect detection experiments, we
explain the positron excess reported by PAMELA through the Breit-Wigner
enhancement mechanism. We also show that our model is consistent with no
antiproton excess suggested by PAMELA.
|
[
{
"created": "Sun, 3 Apr 2011 09:30:59 GMT",
"version": "v1"
},
{
"created": "Sun, 12 Jun 2011 01:25:50 GMT",
"version": "v2"
}
] |
2014-08-19
|
[
[
"Kajiyama",
"Yuji",
""
],
[
"Okada",
"Hiroshi",
""
],
[
"Toma",
"Takashi",
""
]
] |
We study a fermionic dark matter in a non-supersymmetric extension of the standard model with a family symmetry based on D6xZ2xZ2. In our model, the final state of the dark matter annihilation is determined to be e+ e- by the flavor symmetry, which is consistent with the PAMELA result. At first, we show that our dark matter mass should be within the range of 230 GeV - 750 GeV in the WMAP analysis combined with mu to e gamma constraint. Moreover we simultaneously explain the experiments of direct and indirect detection, by simply adding a gauge and D6 singlet real scalar field. In the direct detection experiments, we show that the lighter dark matter mass ~ 230 GeV and the lighter standard model Higgs boson ~ 115 GeV is in favor of the observed bounds reported by CDMS II and XENON100. In the indirect detection experiments, we explain the positron excess reported by PAMELA through the Breit-Wigner enhancement mechanism. We also show that our model is consistent with no antiproton excess suggested by PAMELA.
|
hep-ph/0212360
|
Matthias Neubert
|
Matthias Neubert (Cornell U.)
|
Radiative B Decays: Standard Candles of Flavor Physics
|
12 pages, 10 figures. Invited plenary talk presented at the 10th
International Conference on "Supersymmetry and Unification" (DESY, Hamburg,
17-23 June 2002)
| null | null |
CLNS-03/1814
|
hep-ph
| null |
Rare radiative decays based on b->s+gamma transitions are among the most
prominent examples of flavor-changing neutral current processes. They benefit
from good theoretical control and experimental accessibility, large sensitivity
to physics beyond the Standard Model, and the availability of many observables.
In this talk I summarize the status of the theoretical understanding of these
decays and review how they may be used to constrain extensions of the Standard
Model, with particular focus on supersymmetric models.
|
[
{
"created": "Tue, 24 Dec 2002 16:42:28 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Neubert",
"Matthias",
"",
"Cornell U."
]
] |
Rare radiative decays based on b->s+gamma transitions are among the most prominent examples of flavor-changing neutral current processes. They benefit from good theoretical control and experimental accessibility, large sensitivity to physics beyond the Standard Model, and the availability of many observables. In this talk I summarize the status of the theoretical understanding of these decays and review how they may be used to constrain extensions of the Standard Model, with particular focus on supersymmetric models.
|
1909.08441
|
Yaroslav Krivenko-Emetov D
|
Yaroslav Krivenko-Emetov
|
Attractive inter-particle force in Van der Waals model of hadron gas in
the grand canonical ensemble
|
10 pages, 2 figures
| null | null | null |
hep-ph nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We generalize derivation of partition functions of the grand canonical
ensemble for the multicomponent van der Waals gas of interacting particles by
hardcore potentials to the case of the attractive large-distance mean field.
The formulas obtained by the saddle point method for the thermodynamic
potentials with the transparent non-relativistic limit to the case of
conserving large number of particles for different gas components like neutrons
and protons of nuclear matter can be used for analysis of experimental data for
the particle number ratios in nucleus-nucleus collisions at high excitation
energies.
|
[
{
"created": "Wed, 18 Sep 2019 13:32:49 GMT",
"version": "v1"
}
] |
2019-09-19
|
[
[
"Krivenko-Emetov",
"Yaroslav",
""
]
] |
We generalize derivation of partition functions of the grand canonical ensemble for the multicomponent van der Waals gas of interacting particles by hardcore potentials to the case of the attractive large-distance mean field. The formulas obtained by the saddle point method for the thermodynamic potentials with the transparent non-relativistic limit to the case of conserving large number of particles for different gas components like neutrons and protons of nuclear matter can be used for analysis of experimental data for the particle number ratios in nucleus-nucleus collisions at high excitation energies.
|
0812.2116
|
Vladimir Galkin
|
D. Ebert, R. N. Faustov, V. O. Galkin
|
Masses of light tetraquarks and scalar mesons in the relativistic quark
model
|
9 pages, Report-no added
|
Eur.Phys.J.C60:273-278,2009
|
10.1140/epjc/s10052-009-0925-2
|
HU-EP-08/67
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Masses of the ground state light tetraquarks are dynamically calculated in
the framework of the relativistic diquark-antidiquark picture. The internal
structure of the diquark is taken into account by calculating the form factor
of the diquark-gluon interaction in terms of the overlap integral of the
diquark wave functions. It is found that scalar mesons with masses below 1 GeV:
f_0(600) (\sigma), K^*_0(800) (\kappa), f_0(980) and a_0(980) agree well with
the light tetraquark interpretation.
|
[
{
"created": "Thu, 11 Dec 2008 12:46:12 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Dec 2008 09:41:23 GMT",
"version": "v2"
}
] |
2010-04-15
|
[
[
"Ebert",
"D.",
""
],
[
"Faustov",
"R. N.",
""
],
[
"Galkin",
"V. O.",
""
]
] |
Masses of the ground state light tetraquarks are dynamically calculated in the framework of the relativistic diquark-antidiquark picture. The internal structure of the diquark is taken into account by calculating the form factor of the diquark-gluon interaction in terms of the overlap integral of the diquark wave functions. It is found that scalar mesons with masses below 1 GeV: f_0(600) (\sigma), K^*_0(800) (\kappa), f_0(980) and a_0(980) agree well with the light tetraquark interpretation.
|
1101.3937
|
Helmut Satz
|
Helmut Satz
|
The Quark-Gluon Plasma
|
12 pages, 12 figures; Student Day Lecture, 6th International
Conference on Physics and Astrophysics of Quark Gluon Plasma, Dec. 5 - 10,
2010, Goa/India
|
Nucl.Phys.A862-863:4-12,2011
|
10.1016/j.nuclphysa.2011.05.014
|
BI-TP 2011/02
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
A Short Introduction
|
[
{
"created": "Thu, 20 Jan 2011 15:38:14 GMT",
"version": "v1"
}
] |
2011-07-26
|
[
[
"Satz",
"Helmut",
""
]
] |
A Short Introduction
|
1706.06270
|
Mirzayusuf Musakhanov
|
M. Musakhanov, O. Egamberdiev
|
Dynamical gluon mass in the instanton vacuum model
| null | null |
10.1016/j.physletb.2018.01.080
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We are considering the modifications of gluon properties in Instanton Liquid
Model (ILM) for the QCD vacuum. Re-scattering of a gluons on an instantons
leads to the dynamical momentum-dependent gluon mass $M_g(q).$ First, we
considered scalar "gluon", since there are no zero-modes problem and found its
dynamical mass $M_s(q)$. At the typical phenomenological values of the average
instanton size $\rho=1/3\,\,fm$ and average inter-instanton distance $R=1\,\,
fm$ we got $M_s(0)=256\,\,MeV$. Further, we extended this approach to the real
vector gluon with careful consideration of zero-modes and got
$M^2_g(q)=2M^2_s(q).$ This modification of the gluon in the instanton media
might be important for the heavy quarkonium physics at least.
|
[
{
"created": "Tue, 20 Jun 2017 05:01:47 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Sep 2017 06:54:58 GMT",
"version": "v2"
},
{
"created": "Wed, 31 Jan 2018 18:03:47 GMT",
"version": "v3"
}
] |
2018-02-07
|
[
[
"Musakhanov",
"M.",
""
],
[
"Egamberdiev",
"O.",
""
]
] |
We are considering the modifications of gluon properties in Instanton Liquid Model (ILM) for the QCD vacuum. Re-scattering of a gluons on an instantons leads to the dynamical momentum-dependent gluon mass $M_g(q).$ First, we considered scalar "gluon", since there are no zero-modes problem and found its dynamical mass $M_s(q)$. At the typical phenomenological values of the average instanton size $\rho=1/3\,\,fm$ and average inter-instanton distance $R=1\,\, fm$ we got $M_s(0)=256\,\,MeV$. Further, we extended this approach to the real vector gluon with careful consideration of zero-modes and got $M^2_g(q)=2M^2_s(q).$ This modification of the gluon in the instanton media might be important for the heavy quarkonium physics at least.
|
1508.07359
|
Emerson Luna
|
C. A. S. Bahia, M. Broilo, E.G.S. Luna
|
Energy-dependent dipole form factor in a QCD-inspired model
|
7 pages, 1 figure; Contribution to Proceedings of XIIIth
International Workshop on Hadron Physics, Angra dos Reis, Brazil, 22-27
March, 2015
| null |
10.1088/1742-6596/706/5/052006
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider the effect of an energy-dependent dipole form factor in the
high-energy behavior of the forward amplitude. The connection between the
semihard parton-level dynamics and the hadron-hadron scattering is established
by an eikonal QCD-based model. Our results for the proton-proton ($pp$) and
antiproton-proton ($\bar{p}p$) total cross sections,
$\sigma_{tot}^{pp,\bar{p}p}(s)$, obtained using the CTEQ6L1 parton distribution
function, are consistent with the recent data from the TOTEM experiment.
|
[
{
"created": "Fri, 28 Aug 2015 21:40:31 GMT",
"version": "v1"
}
] |
2016-06-22
|
[
[
"Bahia",
"C. A. S.",
""
],
[
"Broilo",
"M.",
""
],
[
"Luna",
"E. G. S.",
""
]
] |
We consider the effect of an energy-dependent dipole form factor in the high-energy behavior of the forward amplitude. The connection between the semihard parton-level dynamics and the hadron-hadron scattering is established by an eikonal QCD-based model. Our results for the proton-proton ($pp$) and antiproton-proton ($\bar{p}p$) total cross sections, $\sigma_{tot}^{pp,\bar{p}p}(s)$, obtained using the CTEQ6L1 parton distribution function, are consistent with the recent data from the TOTEM experiment.
|
1108.5182
|
Kyoungchul Kong
|
Alan J. Barr, Teng Jian Khoo, Partha Konar, Kyoungchul Kong,
Christopher G. Lester, Konstantin T. Matchev, Myeonghun Park
|
A Storm in a "T" Cup
|
3 pages, 2 figures, presented by K.C. Kong at the 19th Particles and
Nuclei International Conference, PANIC 2011, MIT, Cambridge, MA (July 24-29,
2011)
| null |
10.1063/1.3700663
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We revisit the process of transversification and agglomeration of particle
momenta that are often performed in analyses at hadron colliders, and show that
many of the existing mass-measurement variables proposed for hadron colliders
are far more closely related to each other than is widely appreciated, and
indeed can all be viewed as a common mass bound specialized for a variety of
purposes.
|
[
{
"created": "Thu, 25 Aug 2011 20:02:32 GMT",
"version": "v1"
}
] |
2015-05-30
|
[
[
"Barr",
"Alan J.",
""
],
[
"Khoo",
"Teng Jian",
""
],
[
"Konar",
"Partha",
""
],
[
"Kong",
"Kyoungchul",
""
],
[
"Lester",
"Christopher G.",
""
],
[
"Matchev",
"Konstantin T.",
""
],
[
"Park",
"Myeonghun",
""
]
] |
We revisit the process of transversification and agglomeration of particle momenta that are often performed in analyses at hadron colliders, and show that many of the existing mass-measurement variables proposed for hadron colliders are far more closely related to each other than is widely appreciated, and indeed can all be viewed as a common mass bound specialized for a variety of purposes.
|
hep-ph/9505244
|
Jonathan Bagger
|
Jonathan Bagger, Erich Poppitz, Lisa Randall
|
Destabilizing Divergences in Supergravity Theories at Two Loops
|
Minor changes to references and discussion
|
Nucl.Phys.B455:59-82,1995
|
10.1016/0550-3213(95)00463-3
|
EFI-95-21, JHU-TIPAC-95015, MIT-CTP-2426
|
hep-ph hep-th
| null |
We examine the stability of the mass hierarchy in hidden-sector supergravity
theories. We show that a quadratically divergent tadpole can appear at two
loops, even in minimal supergravity theories, provided the theory has a gauge-
and global-symmetry singlet with renormalizable couplings to the visible
fields. This tadpole can destabilize the hierarchy. We also find a
quadratically divergent two-loop contribution to the field-dependent vacuum
energy. This result casts doubt on the efficacy of the "LHC mechanism" for
controlling quadratic divergences. We carry out the two-loop calculation in a
manifestly supersymmetric formalism, and explain how to apply the formalism in
the presence of supersymmetry breaking to derive radiative corrections to the
supersymmetric and soft supersymmetry-breaking operators. Our approach greatly
simplifies the calculation and guarantees consistency of our results with the
underlying supergravity framework.
|
[
{
"created": "Fri, 5 May 1995 21:39:41 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Aug 1995 19:50:59 GMT",
"version": "v2"
}
] |
2009-09-15
|
[
[
"Bagger",
"Jonathan",
""
],
[
"Poppitz",
"Erich",
""
],
[
"Randall",
"Lisa",
""
]
] |
We examine the stability of the mass hierarchy in hidden-sector supergravity theories. We show that a quadratically divergent tadpole can appear at two loops, even in minimal supergravity theories, provided the theory has a gauge- and global-symmetry singlet with renormalizable couplings to the visible fields. This tadpole can destabilize the hierarchy. We also find a quadratically divergent two-loop contribution to the field-dependent vacuum energy. This result casts doubt on the efficacy of the "LHC mechanism" for controlling quadratic divergences. We carry out the two-loop calculation in a manifestly supersymmetric formalism, and explain how to apply the formalism in the presence of supersymmetry breaking to derive radiative corrections to the supersymmetric and soft supersymmetry-breaking operators. Our approach greatly simplifies the calculation and guarantees consistency of our results with the underlying supergravity framework.
|
hep-ph/9906321
|
Marek Karliner
|
Harry J. Lipkin and Marek Karliner (Tel-Aviv U. and Weizmann Inst.)
|
Nucleon Spin with and without Hyperon Data: A New Tool for Analysis
|
16 pages (latex) with 1 embedded postscript figure. Uses epsfig.sty
|
Phys.Lett. B461 (1999) 280-286
|
10.1016/S0370-2693(99)00823-0
|
TAUP-2572-99 and WIS-99/23/June-DPP
|
hep-ph
| null |
We present a simple explanation of the underlying physics in the use of
hyperon decay data to obtain information about proton spin structure. We also
present an alternative input using nucleon magnetic moment data and show that
the results from the two approaches are nearly identical. The role of symmetry
breaking is clarified while pointing out that simple models explaining the
violation of the Gottfried sum rule via pion emission tend to lose the good
SU(3) predictions from Cabibbo theory for hyperon decays.
|
[
{
"created": "Thu, 10 Jun 1999 14:30:05 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Lipkin",
"Harry J.",
"",
"Tel-Aviv U. and Weizmann Inst."
],
[
"Karliner",
"Marek",
"",
"Tel-Aviv U. and Weizmann Inst."
]
] |
We present a simple explanation of the underlying physics in the use of hyperon decay data to obtain information about proton spin structure. We also present an alternative input using nucleon magnetic moment data and show that the results from the two approaches are nearly identical. The role of symmetry breaking is clarified while pointing out that simple models explaining the violation of the Gottfried sum rule via pion emission tend to lose the good SU(3) predictions from Cabibbo theory for hyperon decays.
|
1302.3181
|
Martin Kr\v{s}\v{s}\'ak
|
Martin Krssak
|
Viscosity Correlators in Improved Holographic QCD
|
10 pages, 8 figures. To appear in the proceedings of the "Barcelona
Postgrad Encounters on Fundamental Physics", University of Barcelona, October
17-19, 2012
| null | null |
BI-TP 2013/03
|
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study a bottom-up holographic model of large-Nc Yang-Mills theory, in
which conformal invariance is broken through the introduction of a dilaton
potential on the gravity side. We use the model to calculate the spectral
densities of the shear and bulk channels at finite temperature. In the shear
channel, we compare our results to those derived in strongly coupled N=4 Super
Yang-Mills theory as well as in weakly coupled ordinary Yang-Mills. In the bulk
channel, where the conformal result is trivial, we make comparisons with both
perturbative and lattice QCD. In both channels, we pay particular attention
into the effects of conformal invariance breaking in the IHQCD model.
|
[
{
"created": "Wed, 13 Feb 2013 18:19:48 GMT",
"version": "v1"
}
] |
2013-02-15
|
[
[
"Krssak",
"Martin",
""
]
] |
We study a bottom-up holographic model of large-Nc Yang-Mills theory, in which conformal invariance is broken through the introduction of a dilaton potential on the gravity side. We use the model to calculate the spectral densities of the shear and bulk channels at finite temperature. In the shear channel, we compare our results to those derived in strongly coupled N=4 Super Yang-Mills theory as well as in weakly coupled ordinary Yang-Mills. In the bulk channel, where the conformal result is trivial, we make comparisons with both perturbative and lattice QCD. In both channels, we pay particular attention into the effects of conformal invariance breaking in the IHQCD model.
|
hep-ph/9410375
|
Jean-Bruno Erismann
|
C. Bourrely, F. Buccella, G. Miele, G, Migliore, J. Soffer, V. Tibullo
|
Fermi-Dirac Distributions for Quark Partons
|
12 pages,CPT-93/P.2961,latex,6 fig available on cpt.univ-mrs.fr
directory pub/preprints/93/fundamental-interactions/93-P.2961
|
Z.Phys.C62:431-436,1994
|
10.1007/BF01555903
| null |
hep-ph
| null |
We propose to use Fermi-Dirac distributions for quark and antiquark partons.
It allows a fair description of the $x$-dependence of the very recent NMC data
on the proton and neutron structure functions $F_2^p(x)$ and $F_2^n(x)$ at
$Q^2=4$ GeV$^2$, as well as the CCFR antiquark distribution $x\overline q(x)$.
We show that one can also use a corresponding Bose-Einstein expression to
describe consistently the gluon distribution. The Pauli exclusion principle,
which has been identified to explain the flavor asymmetry of the light-quark
sea of the proton, is advocated to guide us for making a simple construction of
the polarized parton distributions. We predict the spin dependent structure
functions $g_1^p(x)$ and $g_1^n(x)$ in good agreement with EMC and SLAC data.
The quark distributions involve some parameters whose values support well the
hypothesis that the violation of the quark parton model sum rules is a
consequence of the Pauli principle.
|
[
{
"created": "Wed, 26 Oct 1994 11:01:16 GMT",
"version": "v1"
}
] |
2019-08-17
|
[
[
"Bourrely",
"C.",
""
],
[
"Buccella",
"F.",
""
],
[
"Miele",
"G.",
""
],
[
"G",
"",
""
],
[
"Migliore",
"",
""
],
[
"Soffer",
"J.",
""
],
[
"Tibullo",
"V.",
""
]
] |
We propose to use Fermi-Dirac distributions for quark and antiquark partons. It allows a fair description of the $x$-dependence of the very recent NMC data on the proton and neutron structure functions $F_2^p(x)$ and $F_2^n(x)$ at $Q^2=4$ GeV$^2$, as well as the CCFR antiquark distribution $x\overline q(x)$. We show that one can also use a corresponding Bose-Einstein expression to describe consistently the gluon distribution. The Pauli exclusion principle, which has been identified to explain the flavor asymmetry of the light-quark sea of the proton, is advocated to guide us for making a simple construction of the polarized parton distributions. We predict the spin dependent structure functions $g_1^p(x)$ and $g_1^n(x)$ in good agreement with EMC and SLAC data. The quark distributions involve some parameters whose values support well the hypothesis that the violation of the quark parton model sum rules is a consequence of the Pauli principle.
|
hep-ph/9712241
|
Antonio O. Bouzas
|
Antonio O. Bouzas
|
Perturbative thresholds in the physical region
|
13 + 1 pages, plain LaTeX 2e + PostScript, to appear in Z. Phys. C
|
Eur.Phys.J.C5:167-174,1998
|
10.1007/s100520050258
|
CIEAMER-FIS-971202
|
hep-ph
| null |
We consider unstable-particle scattering in the context of 3-body processes.
We show that all partial-wave cross-sections are finite and positive, and the
total cross-section is proportional to the transverse size of space in the
region of on-shell particle exchange. We comment on the role of loop
corrections.
|
[
{
"created": "Wed, 3 Dec 1997 01:02:47 GMT",
"version": "v1"
}
] |
2011-09-13
|
[
[
"Bouzas",
"Antonio O.",
""
]
] |
We consider unstable-particle scattering in the context of 3-body processes. We show that all partial-wave cross-sections are finite and positive, and the total cross-section is proportional to the transverse size of space in the region of on-shell particle exchange. We comment on the role of loop corrections.
|
hep-ph/0408237
|
Bumseok Kyae
|
S.M. Barr and Bumseok Kyae
|
Time-varying Quark Masses and Cosmological Axion Energy
|
9 pages
|
Phys.Rev.D71:055006,2005
|
10.1103/PhysRevD.71.055006
| null |
hep-ph
| null |
The possibility is examined that the masses of the light quarks $u$ and $d$
have varied over the course of the universe's evolution. Such a variation would
have an effect on axion cosmology, and can be the basis of a solution of the
so-called axion energy problem. If this is the case, a scalar force somewhat
weaker than gravity could exist that has a range of order 1 km.
|
[
{
"created": "Mon, 23 Aug 2004 09:03:48 GMT",
"version": "v1"
}
] |
2011-05-12
|
[
[
"Barr",
"S. M.",
""
],
[
"Kyae",
"Bumseok",
""
]
] |
The possibility is examined that the masses of the light quarks $u$ and $d$ have varied over the course of the universe's evolution. Such a variation would have an effect on axion cosmology, and can be the basis of a solution of the so-called axion energy problem. If this is the case, a scalar force somewhat weaker than gravity could exist that has a range of order 1 km.
|
hep-ph/9805389
|
Gilberto Colangelo
|
J. Bijnens, G. Colangelo and P. Talavera
|
The Vector and Scalar Form Factors of the Pion to Two Loops
|
Latex2e, JHEP.cls, 30 pages 5 figures
|
JHEP9805:014,1998
|
10.1088/1126-6708/1998/05/014
|
LU TP 98-12
|
hep-ph
| null |
We calculate the vector and scalar form factors of the pion to two loops in
Chiral Perturbation Theory. We estimate the unknown O(p^6) constants using
resonance exchange. We make a careful comparison to the available data and
determine two O(p^4) constants rather precisely, and two O(p^6) constants less
precisely. We also use Chiral Perturbation Theory to two loops to extract in a
model--independent manner the charge radius of the pion from the available
data, and obtain \rpiV=0.437\pm 0.016 fm^2.
|
[
{
"created": "Wed, 20 May 1998 12:28:04 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Bijnens",
"J.",
""
],
[
"Colangelo",
"G.",
""
],
[
"Talavera",
"P.",
""
]
] |
We calculate the vector and scalar form factors of the pion to two loops in Chiral Perturbation Theory. We estimate the unknown O(p^6) constants using resonance exchange. We make a careful comparison to the available data and determine two O(p^4) constants rather precisely, and two O(p^6) constants less precisely. We also use Chiral Perturbation Theory to two loops to extract in a model--independent manner the charge radius of the pion from the available data, and obtain \rpiV=0.437\pm 0.016 fm^2.
|
1603.06802
|
Sergio Campos
|
F. S. Borcsik and S. D. Campos
|
Odderon and Pomeron as Fractal Dimension in $pp$ and $\bar{p}p$ Total
Cross Sections
|
8 pages, 3 figures
|
Modern Physics Letters A, Vol. 31, No. 10 (2016)
|
10.1142/S0217732316500668
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
In this paper one presents a naive parametrization to $pp$ and $\bar{p}p$
total cross sections. The main goal of this parametrization is to study the
possible fractal structure present in the total cross section. The result of
the fitting procedure shows two different fractal dimensions: a negative
(low-energies) and a positive (high-energies). The negative fractal dimension
represents the emptiness of the total cross section structure and the positive
represents the filling up process with the energy increase. Hence, the total
cross section presents a multifractal behavior. At low-energies, the odderon
exchange may be associated with the negative fractal dimension and at
high-energies, the pomeron may be associated with the positive fractal
dimension. Therefore, the exchange of odderons and pomerons may be viewed as a
transition from a less well-defined to a more well-defined internal structure,
depending on the energy.
|
[
{
"created": "Tue, 22 Mar 2016 14:14:34 GMT",
"version": "v1"
}
] |
2016-03-23
|
[
[
"Borcsik",
"F. S.",
""
],
[
"Campos",
"S. D.",
""
]
] |
In this paper one presents a naive parametrization to $pp$ and $\bar{p}p$ total cross sections. The main goal of this parametrization is to study the possible fractal structure present in the total cross section. The result of the fitting procedure shows two different fractal dimensions: a negative (low-energies) and a positive (high-energies). The negative fractal dimension represents the emptiness of the total cross section structure and the positive represents the filling up process with the energy increase. Hence, the total cross section presents a multifractal behavior. At low-energies, the odderon exchange may be associated with the negative fractal dimension and at high-energies, the pomeron may be associated with the positive fractal dimension. Therefore, the exchange of odderons and pomerons may be viewed as a transition from a less well-defined to a more well-defined internal structure, depending on the energy.
|
hep-ph/9808402
|
Cheuk-Yin Wong
|
Cheuk-Yin Wong (ORNL)
|
Unresolved Questions in J/psi Production and Propagation in Nuclei
|
10 pages, in LaTex. Talk presented at Workshop on "Particle
Distributions in Hadronic and Nuclear Collisions", University of Illinois at
Chicago, June 11-13, 1998, to be published in the Proceedings
| null | null |
ORNL-CTP-9803
|
hep-ph nucl-th
| null |
In order to understand the J/psi suppression arising from the possible
occurrence of the quark-gluon plasma in high-energy heavy-ion collisions, it is
necessary to have a comprehensive picture how the J/psi and its precursors are
produced, what their properties after production are, and how the J/psi and its
precursors propagate inside nuclear matter. There are unresolved questions in
the descriptions of J/psi production and propagation. We outline some of these
questions and discuss the approaches for their resolution.
|
[
{
"created": "Mon, 24 Aug 1998 19:53:06 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Wong",
"Cheuk-Yin",
"",
"ORNL"
]
] |
In order to understand the J/psi suppression arising from the possible occurrence of the quark-gluon plasma in high-energy heavy-ion collisions, it is necessary to have a comprehensive picture how the J/psi and its precursors are produced, what their properties after production are, and how the J/psi and its precursors propagate inside nuclear matter. There are unresolved questions in the descriptions of J/psi production and propagation. We outline some of these questions and discuss the approaches for their resolution.
|
hep-ph/0402288
|
Sandhya Choubey
|
Sandhya Choubey
|
Solar Neutrino Oscillation Parameters in Experiments with Reactor
Anti-Neutrinos
|
Talk presented at the 2nd International Workshop on Neutrino
oscillations in Venice (NOVE), December 3-5, 2003, Venice, Italy
| null | null | null |
hep-ph
| null |
We review the current status of the solar neutrino oscillation parameters. We
discuss the conditions under which measurements from future solar neutrino
experiments would determine the oscillation parameters precisely. Finally we
expound the potential of long baseline reactor anti-neutrino experiments in
measuring the solar neutrino oscillation parameters.
|
[
{
"created": "Fri, 27 Feb 2004 10:49:40 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Choubey",
"Sandhya",
""
]
] |
We review the current status of the solar neutrino oscillation parameters. We discuss the conditions under which measurements from future solar neutrino experiments would determine the oscillation parameters precisely. Finally we expound the potential of long baseline reactor anti-neutrino experiments in measuring the solar neutrino oscillation parameters.
|
hep-ph/0412385
|
Holger Mueller
|
Holger Mueller
|
Testing Lorentz invariance by use of vacuum and matter filled cavity
resonators
|
15 pages, 8 tables
|
Phys.Rev. D71 (2005) 045004
|
10.1103/PhysRevD.71.045004
| null |
hep-ph
| null |
We consider tests of Lorentz invariance for the photon and fermion sector
that use vacuum and matter-filled cavities. Assumptions on the wave-function of
the electrons in crystals are eliminated from the underlying theory and
accurate sensitivity coefficients (including some exceptionally large ones) are
calculated for various materials. We derive the Lorentz-violating shift in the
index of refraction n, which leads to additional sensitivity for matter-filled
cavities ; and to birefringence in initially isotropic media. Using published
experimental data, we obtain improved bounds on Lorentz violation for photons
and electrons at levels of 10^-15 and below. We discuss implications for future
experiments and propose a new Michelson-Morley type experiment based on
birefringence in matter.
|
[
{
"created": "Sun, 26 Dec 2004 20:55:50 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Mueller",
"Holger",
""
]
] |
We consider tests of Lorentz invariance for the photon and fermion sector that use vacuum and matter-filled cavities. Assumptions on the wave-function of the electrons in crystals are eliminated from the underlying theory and accurate sensitivity coefficients (including some exceptionally large ones) are calculated for various materials. We derive the Lorentz-violating shift in the index of refraction n, which leads to additional sensitivity for matter-filled cavities ; and to birefringence in initially isotropic media. Using published experimental data, we obtain improved bounds on Lorentz violation for photons and electrons at levels of 10^-15 and below. We discuss implications for future experiments and propose a new Michelson-Morley type experiment based on birefringence in matter.
|
1505.00109
|
Kalliopi Petraki
|
Kalliopi Petraki, Marieke Postma and Michael Wiechers
|
Dark-matter bound states from Feynman diagrams
|
36 pages + appendices + references, 9 figures, 1 table; v2: published
version
|
JHEP 1506 (2015) 128
|
10.1007/JHEP06(2015)128
|
NIKHEF-2015-013
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
If dark matter couples directly to a light force mediator, then it may form
bound states in the early universe and in the non-relativistic environment of
haloes today. In this work, we establish a field-theoretic framework for the
computation of bound-state formation cross-sections, de-excitation and decay
rates, in theories with long-range interactions. Using this formalism, we carry
out specific computations for scalar particles interacting either via a light
scalar or vector mediator. At low relative velocities of the interacting
particles, the formation of bound states is enhanced by the Sommerfeld effect.
For particle-antiparticle pairs, we show that bound-state formation can be
faster than annihilation into radiation in the regime where the Sommerfeld
effect is important. The field-theoretic formalism outlined here can be
generalised to compute bound-state formation cross-sections in a variety of
theories, including theories featuring non-Abelian (albeit non-confining)
interactions, such as the electroweak interactions.
|
[
{
"created": "Fri, 1 May 2015 07:35:36 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Jun 2015 12:53:05 GMT",
"version": "v2"
}
] |
2015-06-30
|
[
[
"Petraki",
"Kalliopi",
""
],
[
"Postma",
"Marieke",
""
],
[
"Wiechers",
"Michael",
""
]
] |
If dark matter couples directly to a light force mediator, then it may form bound states in the early universe and in the non-relativistic environment of haloes today. In this work, we establish a field-theoretic framework for the computation of bound-state formation cross-sections, de-excitation and decay rates, in theories with long-range interactions. Using this formalism, we carry out specific computations for scalar particles interacting either via a light scalar or vector mediator. At low relative velocities of the interacting particles, the formation of bound states is enhanced by the Sommerfeld effect. For particle-antiparticle pairs, we show that bound-state formation can be faster than annihilation into radiation in the regime where the Sommerfeld effect is important. The field-theoretic formalism outlined here can be generalised to compute bound-state formation cross-sections in a variety of theories, including theories featuring non-Abelian (albeit non-confining) interactions, such as the electroweak interactions.
|
1104.3449
|
Johannes Bluemlein
|
J. Bl\"umlein, A. Hasselhuhn, P. Kovacikova, S. Moch
|
$O(\alpha_s)$ Heavy Flavor Corrections to Charged Current Deep-Inelastic
Scattering in Mellin Space
|
16 pages, 10 Figures, 1 style file
|
Phys.Lett.B700:294-304,2011
|
10.1016/j.physletb.2011.05.007
|
DESY 11--032, DO--TH 11/06, SFB-CPP/11--19, LPN 11--19
|
hep-ph astro-ph.HE hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We provide a fast and precise Mellin-space implementation of the
$O(\alpha_s)$ heavy flavor Wilson coefficients for charged current deep
inelastic scattering processes. They are of importance for the extraction of
the strange quark distribution in neutrino-nucleon scattering and the QCD
analyses of the HERA charged current data. Errors in the literature are
corrected. We also discuss a series of more general parton parameterizations in
Mellin space.
|
[
{
"created": "Mon, 18 Apr 2011 12:19:53 GMT",
"version": "v1"
}
] |
2015-03-19
|
[
[
"Blümlein",
"J.",
""
],
[
"Hasselhuhn",
"A.",
""
],
[
"Kovacikova",
"P.",
""
],
[
"Moch",
"S.",
""
]
] |
We provide a fast and precise Mellin-space implementation of the $O(\alpha_s)$ heavy flavor Wilson coefficients for charged current deep inelastic scattering processes. They are of importance for the extraction of the strange quark distribution in neutrino-nucleon scattering and the QCD analyses of the HERA charged current data. Errors in the literature are corrected. We also discuss a series of more general parton parameterizations in Mellin space.
|
1812.08129
|
Ulrich Haisch
|
Ulrich Haisch and Giacomo Polesello
|
Searching for dark matter in final states with two jets and missing
transverse energy
|
16 pages, 6 figures, 1 table; v3: one typographical error corrected
| null |
10.1007/JHEP02(2019)128
| null |
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We reemphasise the usefulness of angular correlations in LHC searches for
missing transverse energy ($E_T^{\mathrm{miss}}$) signatures that involve jet
$(j)$ pairs with large invariant mass. For the case of mono-jet production via
gluon-fusion, we develop a realistic analysis strategy that allows to split the
dark matter (DM) signal into distinct one jet-like and two jet-like event
samples. By performing state-of-the-art Monte Carlo simulations of both the
mono-jet signature and the standard model background, it is shown that the
dijet azimuthal angle difference $\Delta \phi_{j_1 j_2}$ in $2 j
+E_T^{\mathrm{miss}}$ production provides a powerful discriminant in realistic
searches. Employing a shape fit to $\Delta \phi_{j_1 j_2}$, we then determine
the LHC reach of the mono-jet channel in the context of spin-0 $s$-channel DM
simplified models. The constraints obtained by the proposed $\Delta \phi_{j_1
j_2}$ shape fit turn out to be significantly more stringent than those that
derive from standard $E_T^{\mathrm{miss}}$ shape analyses.
|
[
{
"created": "Wed, 19 Dec 2018 18:15:02 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Feb 2019 10:13:51 GMT",
"version": "v2"
},
{
"created": "Tue, 19 Feb 2019 07:20:34 GMT",
"version": "v3"
}
] |
2019-03-27
|
[
[
"Haisch",
"Ulrich",
""
],
[
"Polesello",
"Giacomo",
""
]
] |
We reemphasise the usefulness of angular correlations in LHC searches for missing transverse energy ($E_T^{\mathrm{miss}}$) signatures that involve jet $(j)$ pairs with large invariant mass. For the case of mono-jet production via gluon-fusion, we develop a realistic analysis strategy that allows to split the dark matter (DM) signal into distinct one jet-like and two jet-like event samples. By performing state-of-the-art Monte Carlo simulations of both the mono-jet signature and the standard model background, it is shown that the dijet azimuthal angle difference $\Delta \phi_{j_1 j_2}$ in $2 j +E_T^{\mathrm{miss}}$ production provides a powerful discriminant in realistic searches. Employing a shape fit to $\Delta \phi_{j_1 j_2}$, we then determine the LHC reach of the mono-jet channel in the context of spin-0 $s$-channel DM simplified models. The constraints obtained by the proposed $\Delta \phi_{j_1 j_2}$ shape fit turn out to be significantly more stringent than those that derive from standard $E_T^{\mathrm{miss}}$ shape analyses.
|
hep-ph/0506183
|
John Perkins
|
Ben Dundee, John Perkins, and Gerald Cleaver
|
Observable/Hidden Broken Symmetry for Symmetric Boundary Conditions
|
latex, 22 pages
|
Int.J.Mod.Phys. A21 (2006) 3367-3386
|
10.1142/S0217751X06031090
|
BU-HEPP-05/03, CASPER-05/03
|
hep-ph hep-th
| null |
A 4-dimensional heterotic string model of free fermionic construction is
presented wherein mirror symmetry breaking between observable and hidden sector
gauge groups occurs in spite of mirror symmetry between observable and hidden
sector worldsheet fermion boundary conditions. The differentiation is invoked
by an asymmetry in GSO projections necessarily resulting from the symmetry of
the free fermionic boundary conditions. In the specific examples shown, an
expected non-chiral Pati-Salam mirror universe model is transformed into a
chiral model with enhanced hidden sector gauge symmetry and reduced observable
sector gauge symmetry: [SU(4)_C x SU(2)_L x SU(2)_R]_{obs} x [SU(4)_C x SU(2)_L
x SU(2)_R]_{hid} is necessarily transformed into a chiral [SU(4)_C x
SU(2)_L]_{obs} x [SO(10) x SU(2)_R]_{hid} model because of an unavoidable
asymmetry in GSO projections.
|
[
{
"created": "Fri, 17 Jun 2005 19:20:42 GMT",
"version": "v1"
}
] |
2009-11-11
|
[
[
"Dundee",
"Ben",
""
],
[
"Perkins",
"John",
""
],
[
"Cleaver",
"Gerald",
""
]
] |
A 4-dimensional heterotic string model of free fermionic construction is presented wherein mirror symmetry breaking between observable and hidden sector gauge groups occurs in spite of mirror symmetry between observable and hidden sector worldsheet fermion boundary conditions. The differentiation is invoked by an asymmetry in GSO projections necessarily resulting from the symmetry of the free fermionic boundary conditions. In the specific examples shown, an expected non-chiral Pati-Salam mirror universe model is transformed into a chiral model with enhanced hidden sector gauge symmetry and reduced observable sector gauge symmetry: [SU(4)_C x SU(2)_L x SU(2)_R]_{obs} x [SU(4)_C x SU(2)_L x SU(2)_R]_{hid} is necessarily transformed into a chiral [SU(4)_C x SU(2)_L]_{obs} x [SO(10) x SU(2)_R]_{hid} model because of an unavoidable asymmetry in GSO projections.
|
hep-ph/0205299
|
Daniel Wicke
|
D. Wicke (Bergische Universitaet-GH Wuppertal)
|
Hadronic event structure, power corrections and the strong coupling at
LEP
|
5 pages, uses moriond.sty (included). Contribution to "XXXVIIth
Rencontres de Moriond, QCD and hadronic interactions", Les Arcs, France,
March 2002. See http://www.delphi.uni-wuppertal.de/qcd/Talks.html#Moriond2002
| null | null | null |
hep-ph
| null |
Infrared and collinear events shapes are suited to directly probe properties
of hard QCD. They are traditionally used to measure the strong coupling and to
test the gauge structure of QCD. Perturbative predictions exist in several
variations all of which depend on the renormalisation scheme leading to large
theoretical uncertainties in the determination of $alpha_s$. To overcome this
dominating error more and more schemes for setting the renormalisation scale
are investigated. The application of RGI perturbation theory shows an
incredible small spread of $\alpha_s$ indicating a reduced uncertainty and
allows a measurement of the $\beta$-function directly from mean values.
|
[
{
"created": "Mon, 27 May 2002 08:40:36 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Wicke",
"D.",
"",
"Bergische Universitaet-GH Wuppertal"
]
] |
Infrared and collinear events shapes are suited to directly probe properties of hard QCD. They are traditionally used to measure the strong coupling and to test the gauge structure of QCD. Perturbative predictions exist in several variations all of which depend on the renormalisation scheme leading to large theoretical uncertainties in the determination of $alpha_s$. To overcome this dominating error more and more schemes for setting the renormalisation scale are investigated. The application of RGI perturbation theory shows an incredible small spread of $\alpha_s$ indicating a reduced uncertainty and allows a measurement of the $\beta$-function directly from mean values.
|
hep-ph/0004219
|
Dr S. Chaturvedi
|
S. Chaturvedi and N. Mukunda
|
Parametrizing the mixing matrix : A unified approach
|
8 pages, LaTex
|
Int.J.Mod.Phys. A16 (2001) 1481-1490
|
10.1142/S0217751X01003196
| null |
hep-ph
| null |
A unified approach to parametrization of the mixing matrix for $N$
generations is developed. This approach not only has a clear geometrical
underpinning but also has the advantage of being economical and recursive and
leads in a natural way to the known phenomenologically useful parametrizations
of the mixing matrix.
|
[
{
"created": "Tue, 25 Apr 2000 00:18:36 GMT",
"version": "v1"
}
] |
2015-06-25
|
[
[
"Chaturvedi",
"S.",
""
],
[
"Mukunda",
"N.",
""
]
] |
A unified approach to parametrization of the mixing matrix for $N$ generations is developed. This approach not only has a clear geometrical underpinning but also has the advantage of being economical and recursive and leads in a natural way to the known phenomenologically useful parametrizations of the mixing matrix.
|
1709.06085
|
Matthew Reece
|
Prateek Agrawal, JiJi Fan, Matthew Reece, and Lian-Tao Wang
|
Experimental Targets for Photon Couplings of the QCD Axion
|
v2: references added, minor changes, as published in JHEP
|
JHEP 1802 (2018) 006
|
10.1007/JHEP02(2018)006
| null |
hep-ph astro-ph.CO hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The QCD axion's coupling to photons is often assumed to lie in a narrow band
as a function of the axion mass. We demonstrate that several simple mechanisms,
in addition to the photophilic clockwork axion already in the literature, can
significantly extend the allowed range of couplings. Some mechanisms we present
generalize the KNP alignment scenario, widely studied as a model of inflation,
to the phenomenology of a QCD axion. In particular we present KSVZ-like
realizations of two-axion KNP alignment and of the clockwork mechanism. Such a
"confinement tower" realization of clockwork may prove useful in a variety of
model-building contexts. We also show that kinetic mixing of the QCD axion with
a lighter axion-like particle can dramatically alter the QCD axion's coupling
to photons, differing from the other models we present by allowing
non-quantized couplings. The simple models that we present fully cover the
range of axion-photon couplings that could be probed by experiments. They
motivate growing axion detection efforts over a wide space of masses and
couplings.
|
[
{
"created": "Mon, 18 Sep 2017 18:00:00 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Feb 2018 22:34:33 GMT",
"version": "v2"
}
] |
2018-02-16
|
[
[
"Agrawal",
"Prateek",
""
],
[
"Fan",
"JiJi",
""
],
[
"Reece",
"Matthew",
""
],
[
"Wang",
"Lian-Tao",
""
]
] |
The QCD axion's coupling to photons is often assumed to lie in a narrow band as a function of the axion mass. We demonstrate that several simple mechanisms, in addition to the photophilic clockwork axion already in the literature, can significantly extend the allowed range of couplings. Some mechanisms we present generalize the KNP alignment scenario, widely studied as a model of inflation, to the phenomenology of a QCD axion. In particular we present KSVZ-like realizations of two-axion KNP alignment and of the clockwork mechanism. Such a "confinement tower" realization of clockwork may prove useful in a variety of model-building contexts. We also show that kinetic mixing of the QCD axion with a lighter axion-like particle can dramatically alter the QCD axion's coupling to photons, differing from the other models we present by allowing non-quantized couplings. The simple models that we present fully cover the range of axion-photon couplings that could be probed by experiments. They motivate growing axion detection efforts over a wide space of masses and couplings.
|
hep-ph/0701110
|
Tom\'a\v{s} Brauner
|
Tomas Brauner
|
Goldstone bosons in presence of charge density
|
v1: 16 pages, REVTeX4, 7 eps figures; v2: shortened (omitting details
of calculations) on request from referee; version to appear in Phys. Rev. D
|
Phys.Rev.D75:105014,2007
|
10.1103/PhysRevD.75.105014
| null |
hep-ph
| null |
We investigate spontaneous symmetry breaking in Lorentz-noninvariant
theories. Our general discussion includes relativistic systems at finite
density as well as intrinsically nonrelativistic systems. The main result of
the paper is a direct proof that nonzero density of a non-Abelian charge in the
ground state implies the existence of a Goldstone boson with nonlinear
(typically, quadratic) dispersion law. We show that the Goldstone boson
dispersion relation may in general be extracted from the current transition
amplitude and demonstrate on examples from recent literature, how the
calculation of the dispersion relation is utilized by this method. After then,
we use the general results to analyze the nonrelativistic degenerate Fermi gas
of four fermion species. Due to its internal SU(4) symmetry, this system
provides an analog to relativistic two-color quantum chromodynamics with two
quark flavors. In the end, we extend our results to pseudo-Goldstone bosons of
an explicitly broken symmetry.
|
[
{
"created": "Mon, 15 Jan 2007 14:10:38 GMT",
"version": "v1"
},
{
"created": "Mon, 14 May 2007 09:44:37 GMT",
"version": "v2"
}
] |
2008-11-26
|
[
[
"Brauner",
"Tomas",
""
]
] |
We investigate spontaneous symmetry breaking in Lorentz-noninvariant theories. Our general discussion includes relativistic systems at finite density as well as intrinsically nonrelativistic systems. The main result of the paper is a direct proof that nonzero density of a non-Abelian charge in the ground state implies the existence of a Goldstone boson with nonlinear (typically, quadratic) dispersion law. We show that the Goldstone boson dispersion relation may in general be extracted from the current transition amplitude and demonstrate on examples from recent literature, how the calculation of the dispersion relation is utilized by this method. After then, we use the general results to analyze the nonrelativistic degenerate Fermi gas of four fermion species. Due to its internal SU(4) symmetry, this system provides an analog to relativistic two-color quantum chromodynamics with two quark flavors. In the end, we extend our results to pseudo-Goldstone bosons of an explicitly broken symmetry.
|
2106.09031
|
Kristjan M\"u\"ursepp
|
Juan Carlos Criado, Abdelhak Djouadi, Niko Koivunen, Kristjan
M\"u\"ursepp, Martti Raidal, Hardi Veerm\"ae
|
An effective field theory of the Delta-resonance
|
8 pages, 2 figures
| null | null | null |
hep-ph nucl-th
|
http://creativecommons.org/licenses/by/4.0/
|
We present an effective field theory of the $\Delta$-resonance as an
interacting Weinberg's $(3/2,0)\oplus (0,3/2)$ field in the multi-spinor
formalism. We derive its interactions with nucleons $N$, pions $\pi$ and
photons $\gamma$, and compute the $\Delta$-resonance cross-sections in
pion-nucleon scattering and pion photo-production. The theory contains only the
physical spin-3/2 degrees of freedom. Thus, it is intrinsically consistent at
the Hamiltonian level and, unlike the commonly used Rarita-Schwinger framework,
does not require any additional ad hoc manipulation of couplings or
propagators. The symmetries of hadronic physics select a unique operator for
each coupling $N\pi\Delta$ and $\gamma\pi\Delta$. The proposed framework can be
extended to also describe other higher-spin hadronic resonances.
|
[
{
"created": "Wed, 16 Jun 2021 18:00:01 GMT",
"version": "v1"
}
] |
2021-06-18
|
[
[
"Criado",
"Juan Carlos",
""
],
[
"Djouadi",
"Abdelhak",
""
],
[
"Koivunen",
"Niko",
""
],
[
"Müürsepp",
"Kristjan",
""
],
[
"Raidal",
"Martti",
""
],
[
"Veermäe",
"Hardi",
""
]
] |
We present an effective field theory of the $\Delta$-resonance as an interacting Weinberg's $(3/2,0)\oplus (0,3/2)$ field in the multi-spinor formalism. We derive its interactions with nucleons $N$, pions $\pi$ and photons $\gamma$, and compute the $\Delta$-resonance cross-sections in pion-nucleon scattering and pion photo-production. The theory contains only the physical spin-3/2 degrees of freedom. Thus, it is intrinsically consistent at the Hamiltonian level and, unlike the commonly used Rarita-Schwinger framework, does not require any additional ad hoc manipulation of couplings or propagators. The symmetries of hadronic physics select a unique operator for each coupling $N\pi\Delta$ and $\gamma\pi\Delta$. The proposed framework can be extended to also describe other higher-spin hadronic resonances.
|
2109.11032
|
Andrzej Buras
|
Andrzej J. Buras and Elena Venturini
|
Searching for New Physics in Rare $K$ and $B$ Decays without $|V_{cb}|$
and $|V_{ub}|$ Uncertainties
|
44 Pages, 15 Figures. Version 5: A few clarifications added and
cosmetics in a number of formulae made. Figures 5, 6, 7, 9 slightly updated,
conclusions unchanged. Version 6: few references and three footnotes on pages
13, 20 and 25 added
| null | null | null |
hep-ph hep-ex hep-lat
|
http://creativecommons.org/licenses/by/4.0/
|
We reemphasize the strong dependence of the branching ratios
$B(K^+\to\pi^+\nu\bar\nu)$ and $B(K_L\to\pi^0\nu\bar\nu)$ on $|V_{cb}|$ that is
stronger than in rare $B$ decays, in particular for $K_L\to\pi^0\nu\bar\nu$.
Thereby the persistent tension between inclusive and exclusive determinations
of $|V_{cb}|$ weakens the power of these theoretically clean decays in the
search for new physics (NP). We demonstrate how this uncertainty can be
practically removed by considering within the SM suitable ratios of the two
branching ratios between each other and with other observables like the
branching ratios for $K_S\to\mu^+\mu^-$, $B_{s,d}\to\mu^+\mu^-$ and $B\to
K(K^*)\nu\bar\nu$. We use as basic CKM parameters $V_{us}$, $|V_{cb}|$ and the
angles $\beta$ and $\gamma$ in the unitarity triangle (UT). This avoids the use
of the problematic $|V_{ub}|$. A ratio involving $B(K^+\to\pi^+\nu\bar\nu)$ and
$B(B_s\to\mu^+\mu^-)$ while being $|V_{cb}|$-independent exhibits sizable
dependence on the angle $\gamma$. It should be of interest for several
experimental groups in the coming years. We point out that the
$|V_{cb}|$-independent ratio of $B(B^+\to K^+\nu\bar\nu)$ and
$B(B_s\to\mu^+\mu^-)$ from Belle II and LHCb signals a $1.8\sigma$ tension with
its SM value. As a complementary test of the Standard Model, we propose to
extract $|V_{cb}|$ from different observables as a function of $\beta$ and
$\gamma$. We illustrate this with $\epsilon_K$, $\Delta M_d$ and $\Delta M_s$
finding tensions between these three determinations of $|V_{cb}|$ within the
SM. From $\Delta M_s$ and $S_{\psi K_S}$ alone we find $|V_{cb}|=41.8(6)\times
10^{-3}$ and $|V_{ub}|=3.65(12)\times 10^{-3}$. We stress the importance of a
precise measurement of $\gamma$. We obtain most precise SM predictions for
considered branching ratios of rare K and B decays to date.
|
[
{
"created": "Wed, 22 Sep 2021 20:39:52 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Oct 2021 14:39:34 GMT",
"version": "v2"
},
{
"created": "Tue, 26 Oct 2021 19:22:22 GMT",
"version": "v3"
},
{
"created": "Thu, 13 Jan 2022 22:15:06 GMT",
"version": "v4"
},
{
"created": "Thu, 24 Mar 2022 16:33:54 GMT",
"version": "v5"
},
{
"created": "Wed, 1 Jun 2022 19:05:57 GMT",
"version": "v6"
}
] |
2022-06-03
|
[
[
"Buras",
"Andrzej J.",
""
],
[
"Venturini",
"Elena",
""
]
] |
We reemphasize the strong dependence of the branching ratios $B(K^+\to\pi^+\nu\bar\nu)$ and $B(K_L\to\pi^0\nu\bar\nu)$ on $|V_{cb}|$ that is stronger than in rare $B$ decays, in particular for $K_L\to\pi^0\nu\bar\nu$. Thereby the persistent tension between inclusive and exclusive determinations of $|V_{cb}|$ weakens the power of these theoretically clean decays in the search for new physics (NP). We demonstrate how this uncertainty can be practically removed by considering within the SM suitable ratios of the two branching ratios between each other and with other observables like the branching ratios for $K_S\to\mu^+\mu^-$, $B_{s,d}\to\mu^+\mu^-$ and $B\to K(K^*)\nu\bar\nu$. We use as basic CKM parameters $V_{us}$, $|V_{cb}|$ and the angles $\beta$ and $\gamma$ in the unitarity triangle (UT). This avoids the use of the problematic $|V_{ub}|$. A ratio involving $B(K^+\to\pi^+\nu\bar\nu)$ and $B(B_s\to\mu^+\mu^-)$ while being $|V_{cb}|$-independent exhibits sizable dependence on the angle $\gamma$. It should be of interest for several experimental groups in the coming years. We point out that the $|V_{cb}|$-independent ratio of $B(B^+\to K^+\nu\bar\nu)$ and $B(B_s\to\mu^+\mu^-)$ from Belle II and LHCb signals a $1.8\sigma$ tension with its SM value. As a complementary test of the Standard Model, we propose to extract $|V_{cb}|$ from different observables as a function of $\beta$ and $\gamma$. We illustrate this with $\epsilon_K$, $\Delta M_d$ and $\Delta M_s$ finding tensions between these three determinations of $|V_{cb}|$ within the SM. From $\Delta M_s$ and $S_{\psi K_S}$ alone we find $|V_{cb}|=41.8(6)\times 10^{-3}$ and $|V_{ub}|=3.65(12)\times 10^{-3}$. We stress the importance of a precise measurement of $\gamma$. We obtain most precise SM predictions for considered branching ratios of rare K and B decays to date.
|
hep-ph/0512372
|
Luca Trentadue
|
Federico Alberto Ceccopieri, Luca Trentadue
|
Transverse Momentum in Semi-inclusive Deep Inelastic Scattering
|
11 pages, 5 figures
|
Phys.Lett.B636:310-316,2006
|
10.1016/j.physletb.2006.03.068
| null |
hep-ph
| null |
Within the framework of perturbative Quantum Chromodynamics we derive
transverse momentum dependent distributions describing both current and target
fragmentation in semi-inclusive Deep Inelastic Scattering. We present, to
leading logarithmic accuracy, the corresponding crosssections describing final
state hadrons on the whole phase space. Phenomenological implications and
further developments are briefly discussed.
|
[
{
"created": "Fri, 30 Dec 2005 12:30:57 GMT",
"version": "v1"
}
] |
2008-11-26
|
[
[
"Ceccopieri",
"Federico Alberto",
""
],
[
"Trentadue",
"Luca",
""
]
] |
Within the framework of perturbative Quantum Chromodynamics we derive transverse momentum dependent distributions describing both current and target fragmentation in semi-inclusive Deep Inelastic Scattering. We present, to leading logarithmic accuracy, the corresponding crosssections describing final state hadrons on the whole phase space. Phenomenological implications and further developments are briefly discussed.
|
hep-ph/9906398
|
Marcus Bleicher
|
M. Bleicher, S.A Bass, H. St\"ocker, W. Greiner (Institut f\"ur
Theoretische Physik, J.W.Goethe Universit\"at, Frankfurt am Main, Germany)
|
RHIC predictions from the UrQMD model
|
6 pages, 5 eps figures,Latex 2e Talk given in the RHIC session of
Quark Matter 99
| null | null | null |
hep-ph
| null |
The Ultra-relativistic Quantum-Molecular-Dynamics model (UrQMD) is used to
study central Pb+Pb reactions at RHIC ($\sqrt{s}=200$ AGeV). The computed
collision spectrum reveals that the major part (approx. 80%) of the dynamics is
governed by interactions below $\sqrt{s}=100$ GeV. Rapidity spectra of
net-baryons (Protons, Hyperons) and produced particles (Pions, Kaons) are
predicted. The transverse expansion is studied.
|
[
{
"created": "Wed, 16 Jun 1999 18:37:21 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Bleicher",
"M.",
"",
"Institut für\n Theoretische Physik, J.W.Goethe Universität, Frankfurt am Main, Germany"
],
[
"Bass",
"S. A",
"",
"Institut für\n Theoretische Physik, J.W.Goethe Universität, Frankfurt am Main, Germany"
],
[
"Stöcker",
"H.",
"",
"Institut für\n Theoretische Physik, J.W.Goethe Universität, Frankfurt am Main, Germany"
],
[
"Greiner",
"W.",
"",
"Institut für\n Theoretische Physik, J.W.Goethe Universität, Frankfurt am Main, Germany"
]
] |
The Ultra-relativistic Quantum-Molecular-Dynamics model (UrQMD) is used to study central Pb+Pb reactions at RHIC ($\sqrt{s}=200$ AGeV). The computed collision spectrum reveals that the major part (approx. 80%) of the dynamics is governed by interactions below $\sqrt{s}=100$ GeV. Rapidity spectra of net-baryons (Protons, Hyperons) and produced particles (Pions, Kaons) are predicted. The transverse expansion is studied.
|
1308.6338
|
Valentin V. Khoze
|
Valentin V. Khoze
|
Inflation and Dark Matter in the Higgs Portal of Classically Scale
Invariant Standard Model
|
v2: References added, minor corrections, matches JHEP version, 23
pages
| null |
10.1007/JHEP11(2013)215
|
IPPP/13/65, DCPT/13/130
|
hep-ph astro-ph.HE hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider a minimal classically scale-invariant extension of the Standard
Model. In this theory, the Higgs mechanism is triggered and the electroweak
symmetry breaking is generated radiatively by the Coleman-Weinberg sector which
is coupled to the SM Higgs. We extend the Higgs portal interactions of the
theory to include an additional singlet which is also non-minimally coupled to
gravity. This generates a single-field slow-roll inflation mechanism in the
effective field theory formulation which is robust up to Planck scales. Our
approach does not require integrating in any additional new physics degrees of
freedom to unitarise the theory in the sub-Planckian regime where inflation
happens. As a result, no large threshold corrections appear in our approach to
inflation so that the electroweak scale and the SM Higgs mass are not affected.
The singlet field responsible for inflation also gives a viable dark matter
candidate in our model. We also discuss the relation between classical
scale-invariance of the effective theory and the possible local scale
invariance of the full theory and comment on the naturalness of the electroweak
scale.
|
[
{
"created": "Thu, 29 Aug 2013 01:19:54 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Nov 2013 17:17:31 GMT",
"version": "v2"
}
] |
2015-06-17
|
[
[
"Khoze",
"Valentin V.",
""
]
] |
We consider a minimal classically scale-invariant extension of the Standard Model. In this theory, the Higgs mechanism is triggered and the electroweak symmetry breaking is generated radiatively by the Coleman-Weinberg sector which is coupled to the SM Higgs. We extend the Higgs portal interactions of the theory to include an additional singlet which is also non-minimally coupled to gravity. This generates a single-field slow-roll inflation mechanism in the effective field theory formulation which is robust up to Planck scales. Our approach does not require integrating in any additional new physics degrees of freedom to unitarise the theory in the sub-Planckian regime where inflation happens. As a result, no large threshold corrections appear in our approach to inflation so that the electroweak scale and the SM Higgs mass are not affected. The singlet field responsible for inflation also gives a viable dark matter candidate in our model. We also discuss the relation between classical scale-invariance of the effective theory and the possible local scale invariance of the full theory and comment on the naturalness of the electroweak scale.
|
hep-ph/9811241
|
R. Cowsik
|
R. Cowsik & B.V.Sreekantan
|
A Bound on Violations of Lorentz Invariance
|
7 pages, 1 figure
|
Phys.Lett. B449 (1999) 219-222
|
10.1016/S0370-2693(99)00016-7
| null |
hep-ph
| null |
Recently Coleman and Glashow [1] have developed a model which allows the
introduction of a small violation of Lorentz invariance. Observational
signatures arise because this interaction also violates flavor conservation and
allows the radiative decay of the muon, $\mu \to e + \gamma$, whose branching
ratio increases as b $\gamma^4$ where $\gamma$ is the Lorentz factor of the
muon with respect to the reference frame in which the dipole anisotropy of the
universal microwave radiation vanishes. In this paper we place a bound of b$<
10^{-25}$ based on observations of horizontal air showers with $n_e \geq 5
\times 10^6$. With such small values of b the proposed radiative decay of the
muon will not affect the functioning of the muon collider.(THIS IS A
PRELIMINARY VERSION)
|
[
{
"created": "Wed, 4 Nov 1998 13:45:32 GMT",
"version": "v1"
},
{
"created": "Sat, 7 Nov 1998 11:27:16 GMT",
"version": "v2"
}
] |
2009-10-31
|
[
[
"Cowsik",
"R.",
""
],
[
"Sreekantan",
"B. V.",
""
]
] |
Recently Coleman and Glashow [1] have developed a model which allows the introduction of a small violation of Lorentz invariance. Observational signatures arise because this interaction also violates flavor conservation and allows the radiative decay of the muon, $\mu \to e + \gamma$, whose branching ratio increases as b $\gamma^4$ where $\gamma$ is the Lorentz factor of the muon with respect to the reference frame in which the dipole anisotropy of the universal microwave radiation vanishes. In this paper we place a bound of b$< 10^{-25}$ based on observations of horizontal air showers with $n_e \geq 5 \times 10^6$. With such small values of b the proposed radiative decay of the muon will not affect the functioning of the muon collider.(THIS IS A PRELIMINARY VERSION)
|
hep-ph/0104221
|
Daniele Montanino
|
G.L. Fogli, E. Lisi, A. Marrone (Bari U. & INFN, Bari), D. Montanino
(Lecce U.), and A. Palazzo (Bari U. & INFN, Bari)
|
Atmospheric, Solar, and CHOOZ neutrinos: a global three generation
analysis
|
4 pages, talk given at 36th Rencontres de Moriond: Electroweak
Interactions and Unified Theories, Les Arcs, France, 10-17 Mar 2001
| null | null | null |
hep-ph
| null |
We perform a global three generation analysis of the current solar and
atmospheric evidence in favor of neutrino oscillations. We also include the
negative results coming from CHOOZ to constrain the nu_e mixing. We study the
zones of mass-mixing oscillations parameters compatible with all the data. It
is shown that almost pure nu_mu <--> nu_tau oscillations are required to
explain the atmospheric neutrino anomaly and almost pure nu_1 <--> nu_2
oscillations to account for the solar neutrino deficit.
|
[
{
"created": "Mon, 23 Apr 2001 10:30:28 GMT",
"version": "v1"
}
] |
2007-05-23
|
[
[
"Fogli",
"G. L.",
"",
"Bari U. & INFN, Bari"
],
[
"Lisi",
"E.",
"",
"Bari U. & INFN, Bari"
],
[
"Marrone",
"A.",
"",
"Bari U. & INFN, Bari"
],
[
"Montanino",
"D.",
"",
"Lecce U."
],
[
"Palazzo",
"A.",
"",
"Bari U. & INFN, Bari"
]
] |
We perform a global three generation analysis of the current solar and atmospheric evidence in favor of neutrino oscillations. We also include the negative results coming from CHOOZ to constrain the nu_e mixing. We study the zones of mass-mixing oscillations parameters compatible with all the data. It is shown that almost pure nu_mu <--> nu_tau oscillations are required to explain the atmospheric neutrino anomaly and almost pure nu_1 <--> nu_2 oscillations to account for the solar neutrino deficit.
|
hep-ph/9902429
|
Chi-Sing Lam
|
Rim Dib, Justin Khoury, and C.S. Lam
|
Unitarized Diffractive Scattering in QCD and Application to Virtual
Photon Total Cross Sections
|
41 pages in revtex preprint format, with 10 figures
|
Phys.Rev.D60:036001,1999
|
10.1103/PhysRevD.60.036001
|
McGill/99-8
|
hep-ph
| null |
The problem of restoring Froissart bound to the BFKL-Pomeron is studied in an
extended leading-log approximation of QCD. We consider parton-parton scattering
amplitude and show that the sum of all Feynman-diagram contributions can be
written in an eikonal form. In this form dynamics is determined by the phase
shift, and subleading-logs of all orders needed to restore the Froissart bound
are automatically provided. The main technical difficulty is to find a way to
extract these subleading contributions without having to compute each Feynman
diagram beyond the leading order. We solve that problem by using nonabelian cut
diagrams introduced elsewhere. They can be considered as colour filters used to
isolate the multi-Reggeon contributions that supply these subleading-log terms.
Illustration of the formalism is given for amplitudes and phase shifts up to
three loops. For diffractive scattering, only phase shifts governed by one and
two Reggeon exchanges are needed. They can be computed from the
leading-log-Reggeon and the BFKL-Pomeron amplitudes. In applications, we argue
that the dependence of the energy-growth exponent on virtuality $Q^2$ for
$\gamma^*P$ total cross section observed at HERA can be interpreted as the
first sign of a slowdown of energy growth towards satisfying the Froissart
bound. An attempt to understand these exponents with the present formalism is
discussed.
|
[
{
"created": "Mon, 22 Feb 1999 19:17:59 GMT",
"version": "v1"
}
] |
2014-11-17
|
[
[
"Dib",
"Rim",
""
],
[
"Khoury",
"Justin",
""
],
[
"Lam",
"C. S.",
""
]
] |
The problem of restoring Froissart bound to the BFKL-Pomeron is studied in an extended leading-log approximation of QCD. We consider parton-parton scattering amplitude and show that the sum of all Feynman-diagram contributions can be written in an eikonal form. In this form dynamics is determined by the phase shift, and subleading-logs of all orders needed to restore the Froissart bound are automatically provided. The main technical difficulty is to find a way to extract these subleading contributions without having to compute each Feynman diagram beyond the leading order. We solve that problem by using nonabelian cut diagrams introduced elsewhere. They can be considered as colour filters used to isolate the multi-Reggeon contributions that supply these subleading-log terms. Illustration of the formalism is given for amplitudes and phase shifts up to three loops. For diffractive scattering, only phase shifts governed by one and two Reggeon exchanges are needed. They can be computed from the leading-log-Reggeon and the BFKL-Pomeron amplitudes. In applications, we argue that the dependence of the energy-growth exponent on virtuality $Q^2$ for $\gamma^*P$ total cross section observed at HERA can be interpreted as the first sign of a slowdown of energy growth towards satisfying the Froissart bound. An attempt to understand these exponents with the present formalism is discussed.
|
hep-ph/9704299
|
Thomas Binoth
|
T. Binoth, A. Ghinculov (University of Freiburg, Germany)
|
Radiative corrections to the lineshape of a heavy Higgs boson at muon
colliders
|
9 pages LaTex, 3 eps figures included
|
Phys.Rev. D56 (1997) 3147-3150
|
10.1103/PhysRevD.56.3147
|
Freiburg-THEP 97/08
|
hep-ph
| null |
We study the NNLO radiative corrections of enhanced electroweak strength to
the lineshape of the Higgs boson in the processes ($\mu^+\mu^- \to H \to ZZ$)
and ($\mu^+\mu^- \to H \to t\bar t$), which are of interest for Higgs searches
at a possible muon collider. We give the radiative corrections both in the
on-shell renormalization scheme and in the pole renormalization scheme. The
pole scheme appears to have better convergence properties, in agreement with
previous results regarding the position of the Higgs pole in the complex plane.
|
[
{
"created": "Fri, 11 Apr 1997 18:53:09 GMT",
"version": "v1"
}
] |
2009-10-30
|
[
[
"Binoth",
"T.",
"",
"University of Freiburg, Germany"
],
[
"Ghinculov",
"A.",
"",
"University of Freiburg, Germany"
]
] |
We study the NNLO radiative corrections of enhanced electroweak strength to the lineshape of the Higgs boson in the processes ($\mu^+\mu^- \to H \to ZZ$) and ($\mu^+\mu^- \to H \to t\bar t$), which are of interest for Higgs searches at a possible muon collider. We give the radiative corrections both in the on-shell renormalization scheme and in the pole renormalization scheme. The pole scheme appears to have better convergence properties, in agreement with previous results regarding the position of the Higgs pole in the complex plane.
|
hep-ph/9902313
|
Abner Soffer
|
Abner Soffer
|
Discrete Ambiguities in the Measurement of the Weak Phase Gamma
|
15 pages, 2 figures, fixed typo
|
Phys.Rev.D60:054032,1999
|
10.1103/PhysRevD.60.054032
|
SLAC-PUB-8047
|
hep-ph
| null |
Several time-independent methods have been devised for measuring the phase
gamma of the Cabibbo-Kobayashi-Maskawa unitarity triangle. It is shown that
such measurements generally suffer from discrete ambiguity which is at least
8-fold, not 4-fold as commonly stated. This has serious experimental
implications, which are explored in methods involving B->DK decays. The
measurement sensitivity and new physics discovery potential are estimated using
a full Monte Carlo detector simulation with realistic background estimates.
|
[
{
"created": "Thu, 11 Feb 1999 01:21:20 GMT",
"version": "v1"
},
{
"created": "Tue, 25 May 1999 18:35:55 GMT",
"version": "v2"
},
{
"created": "Tue, 6 Jul 1999 20:21:05 GMT",
"version": "v3"
}
] |
2010-11-23
|
[
[
"Soffer",
"Abner",
""
]
] |
Several time-independent methods have been devised for measuring the phase gamma of the Cabibbo-Kobayashi-Maskawa unitarity triangle. It is shown that such measurements generally suffer from discrete ambiguity which is at least 8-fold, not 4-fold as commonly stated. This has serious experimental implications, which are explored in methods involving B->DK decays. The measurement sensitivity and new physics discovery potential are estimated using a full Monte Carlo detector simulation with realistic background estimates.
|
2305.15830
|
Narmin Akbarova Dr.
|
Minaya Allahverdiyeva, Narmin Huseynova, Shahin Mamedov, Jannat
Samadov
|
The magnetic properties of a deuteron $r_m$ from the AdS/QCD hard-wall
model
|
3 pages, CO\.IA-2022 conference proceeding
| null | null | null |
hep-ph nucl-th
|
http://creativecommons.org/licenses/by-nc-nd/4.0/
|
The deuteron is a spin1 particle and due to current conservation and the P
and C invariance of the EM interaction, it has three EM form factors in the one
photon exchange (OPE) approximation, which include the charge GC(Q2),
quadrupole GQ(Q2) and magnetic GM(Q2) form factors and was calculated in [1, 2,
3] at a zero temperature within soft-wall and hard-wall models AdS/QCD. In this
work, we numerically calculated the deuteron magnetic radius RM in the
framework of the hard-wall model of AdS/QCD and compare our results with the
experimental data and soft-wall model results [2]
|
[
{
"created": "Thu, 25 May 2023 08:18:42 GMT",
"version": "v1"
}
] |
2023-05-26
|
[
[
"Allahverdiyeva",
"Minaya",
""
],
[
"Huseynova",
"Narmin",
""
],
[
"Mamedov",
"Shahin",
""
],
[
"Samadov",
"Jannat",
""
]
] |
The deuteron is a spin1 particle and due to current conservation and the P and C invariance of the EM interaction, it has three EM form factors in the one photon exchange (OPE) approximation, which include the charge GC(Q2), quadrupole GQ(Q2) and magnetic GM(Q2) form factors and was calculated in [1, 2, 3] at a zero temperature within soft-wall and hard-wall models AdS/QCD. In this work, we numerically calculated the deuteron magnetic radius RM in the framework of the hard-wall model of AdS/QCD and compare our results with the experimental data and soft-wall model results [2]
|
hep-ph/0104110
|
Martin Beneke
|
M. Beneke (RWTH Aachen), G. Buchalla (CERN), M. Neubert (Cornell U.),
C.T. Sachrajda (Southampton U.)
|
QCD Factorization in B -> pi K, pi pi Decays and Extraction of
Wolfenstein Parameters
|
81 pages, LaTeX
|
Nucl.Phys.B606:245-321,2001
|
10.1016/S0550-3213(01)00251-6
|
CERN-TH/2001-107, CLNS 01/1728, PITHA 01/01, SHEP 01/11
|
hep-ph
| null |
In the heavy-quark limit, the hadronic matrix elements entering nonleptonic
$B$-meson decays into two light mesons can be calculated from first principles
including ``nonfactorizable'' strong-interaction corrections. The $B\to\pi
K,\pi\pi$ decay amplitudes are computed including electroweak penguin
contributions, SU(3) violation in the light-cone distribution amplitudes, and
an estimate of power corrections from chirally-enhanced terms and annihilation
graphs. The results are then used to reduce the theoretical uncertainties in
determinations of the weak phases $\gamma$ and $\alpha$. In that way, new
constraints in the $(\bar\rho,\bar\eta)$ plane are derived. Predictions for the
$B\to\pi K, \pi\pi$ branching ratios and CP asymmetries are also presented. A
good global fit to the (in part preliminary) experimental data on the branching
fractions is obtained without taking recourse to phenomenological models.
|
[
{
"created": "Wed, 11 Apr 2001 16:21:37 GMT",
"version": "v1"
}
] |
2010-05-28
|
[
[
"Beneke",
"M.",
"",
"RWTH Aachen"
],
[
"Buchalla",
"G.",
"",
"CERN"
],
[
"Neubert",
"M.",
"",
"Cornell U."
],
[
"Sachrajda",
"C. T.",
"",
"Southampton U."
]
] |
In the heavy-quark limit, the hadronic matrix elements entering nonleptonic $B$-meson decays into two light mesons can be calculated from first principles including ``nonfactorizable'' strong-interaction corrections. The $B\to\pi K,\pi\pi$ decay amplitudes are computed including electroweak penguin contributions, SU(3) violation in the light-cone distribution amplitudes, and an estimate of power corrections from chirally-enhanced terms and annihilation graphs. The results are then used to reduce the theoretical uncertainties in determinations of the weak phases $\gamma$ and $\alpha$. In that way, new constraints in the $(\bar\rho,\bar\eta)$ plane are derived. Predictions for the $B\to\pi K, \pi\pi$ branching ratios and CP asymmetries are also presented. A good global fit to the (in part preliminary) experimental data on the branching fractions is obtained without taking recourse to phenomenological models.
|
1002.2758
|
Chang Qin
|
Qin Chang, Xin-Qiang Li, Ya-Dong Yang
|
$B \to K^{\ast} l^+ l^-$, $K l^+ l^-$ decays in a family non-universal
$Z^{\prime}$ model
|
20 pages, 3 figures. To appear in JHEP
|
JHEP 1004:052,2010
|
10.1007/JHEP04(2010)052
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Motivated by the observed forward-backward asymmetry in $B\to K^{\ast} l^+
l^-$ decay, we perform a detailed analysis of this decay mode within a family
non-universal $Z^{\prime}$ model. With the related coupling
$Z^{\prime}-\bar{s}b$ constrained by $\bar{B}_s-B_s$ mixing, $B\to \pi K$, and
$B\to X_s \mu^{+}\mu^{-}$ decays, we look for further constraint on the
couplings $Z^{\prime}-\mu^{+}\mu^{-}$ from $A_{FB}(B\to K^{\ast}
\mu^{+}\mu^{-})_{0 {\rm GeV}^2\leqslant q^2\leqslant 2 {\rm GeV}^2}$ and get
numerically $B_{\mu\mu}^{L,R}\sim{\cal O}(10^{-2})$. Moreover, we find that the
relations, $B_{\mu\mu}^{L}<B_{\mu\mu}^{R}$ and
$B_{\mu\mu}^{L}+B_{\mu\mu}^{R}<0$, with a small negative $\phi_{s}^{L}$, are
crucial to moderate the discrepancy for $A_{FB}(B\to K^{\ast} \mu^{+}\mu^{-})$
between the SM prediction and the experimental data. Numerically, comparing
with the SM prediction, we find that $A_{FB}(B\to K^{\ast} \mu^{+}\mu^{-})_{0
{\rm GeV}^2\leqslant q^2\leqslant 2 {\rm GeV}^2}$ could be enhanced about 80%
and 50% by $Z^{\prime}$ contribution at most in scenarios S1 and S2,
corresponding to the two fitted results of $\phi_{s}$ by UTfit collaboration,
respectively. However, the results are still about $1.5\sigma$ lower than the
experimental measurement.
|
[
{
"created": "Sun, 14 Feb 2010 08:32:21 GMT",
"version": "v1"
},
{
"created": "Sat, 27 Mar 2010 09:11:24 GMT",
"version": "v2"
}
] |
2014-11-20
|
[
[
"Chang",
"Qin",
""
],
[
"Li",
"Xin-Qiang",
""
],
[
"Yang",
"Ya-Dong",
""
]
] |
Motivated by the observed forward-backward asymmetry in $B\to K^{\ast} l^+ l^-$ decay, we perform a detailed analysis of this decay mode within a family non-universal $Z^{\prime}$ model. With the related coupling $Z^{\prime}-\bar{s}b$ constrained by $\bar{B}_s-B_s$ mixing, $B\to \pi K$, and $B\to X_s \mu^{+}\mu^{-}$ decays, we look for further constraint on the couplings $Z^{\prime}-\mu^{+}\mu^{-}$ from $A_{FB}(B\to K^{\ast} \mu^{+}\mu^{-})_{0 {\rm GeV}^2\leqslant q^2\leqslant 2 {\rm GeV}^2}$ and get numerically $B_{\mu\mu}^{L,R}\sim{\cal O}(10^{-2})$. Moreover, we find that the relations, $B_{\mu\mu}^{L}<B_{\mu\mu}^{R}$ and $B_{\mu\mu}^{L}+B_{\mu\mu}^{R}<0$, with a small negative $\phi_{s}^{L}$, are crucial to moderate the discrepancy for $A_{FB}(B\to K^{\ast} \mu^{+}\mu^{-})$ between the SM prediction and the experimental data. Numerically, comparing with the SM prediction, we find that $A_{FB}(B\to K^{\ast} \mu^{+}\mu^{-})_{0 {\rm GeV}^2\leqslant q^2\leqslant 2 {\rm GeV}^2}$ could be enhanced about 80% and 50% by $Z^{\prime}$ contribution at most in scenarios S1 and S2, corresponding to the two fitted results of $\phi_{s}$ by UTfit collaboration, respectively. However, the results are still about $1.5\sigma$ lower than the experimental measurement.
|
1703.00722
|
Igor Dyatlov Tichonovitch
|
Igor T. Dyatlov
|
Structures of Neutrino Mass Spectrum and Lepton Mixing: Results of
Violated Mirror Symmetry
|
18 pages, 2 figures
| null |
10.1134/S106377881704007X
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The specific violated mirror symmetry model is capable of generating the
observed lepton weak mixing matrix with a structure similar to the observed one
that almost lacks any visible regularities (the "flavor riddle"). The
peculiarities of the Standard Model (SM): quark and lepton mass hierarchy and
the neutrino spectrum different from this hierarchy appear to be necessary
conditions for reproduction of such a structure. The inverse order of the
neutrino spectrum and a small value of the mass $m_{3}$ are here two other
necessary conditions. The smallness of the angle $\Theta_{1,3}$ is determined
then just by small mass ratios in the hierarchical lepton spectrum. The
explanation is proposed for differences between the neutrino spectrum and other
fermion spectra of SM. The inverse order of the neutrino spectrum and the
observed $\Theta_{1,3}$ angle permit evaluation of the absolute values of
neutrino masses: $m_{1}\sim m_{2}\sim 0.05$eV, $m_{3}\leq 0.01$eV.
|
[
{
"created": "Thu, 2 Mar 2017 11:21:24 GMT",
"version": "v1"
}
] |
2017-09-13
|
[
[
"Dyatlov",
"Igor T.",
""
]
] |
The specific violated mirror symmetry model is capable of generating the observed lepton weak mixing matrix with a structure similar to the observed one that almost lacks any visible regularities (the "flavor riddle"). The peculiarities of the Standard Model (SM): quark and lepton mass hierarchy and the neutrino spectrum different from this hierarchy appear to be necessary conditions for reproduction of such a structure. The inverse order of the neutrino spectrum and a small value of the mass $m_{3}$ are here two other necessary conditions. The smallness of the angle $\Theta_{1,3}$ is determined then just by small mass ratios in the hierarchical lepton spectrum. The explanation is proposed for differences between the neutrino spectrum and other fermion spectra of SM. The inverse order of the neutrino spectrum and the observed $\Theta_{1,3}$ angle permit evaluation of the absolute values of neutrino masses: $m_{1}\sim m_{2}\sim 0.05$eV, $m_{3}\leq 0.01$eV.
|
hep-ph/9812418
|
Sheldon Lee Glashow, Hpop
|
Sidney Coleman and Sheldon L. Glashow
|
High-Energy Tests of Lorentz Invariance
|
33 pages, uses harvmac. This 2nd revision corrects two typos, an
error in the Appendix, and includes further acknowledgements
|
Phys.Rev.D59:116008,1999
|
10.1103/PhysRevD.59.116008
|
HUTP-98/A082
|
hep-ph
| null |
We develop a perturbative framework with which to discuss departures from
exact Lorentz invariance and explore their potentially observable
ramifications. Tiny non-invariant terms introduced into the standard model
Lagrangian are assumed to be renormalizable (dimension $\le 4$), invariant
under $SU(3)\otimes SU(2)\otimes U(1)$ gauge transformations, and rotationally
and translationally invariant in a preferred frame. There are a total of 46
independent TCP-even perturbations of this kind, all of which preserve anomaly
cancellation. They define the energy-momentum eigenstates and their maximal
attainable velocities in the high-energy limit. The effects of these
perturbations increase rapidly with energy in the preferred frame, more rapidly
than those of TCP-odd perturbations. Our analysis of Lorentz-violating
kinematics reveals several striking new phenomena that are relevant both to
cosmic-ray physics ({\it e.g.,} by undoing the GZK cutoff) and neutrino physics
({\it e.g.,} by generating novel types of neutrino oscillations). These may
lead to new and sensitive high-energy tests of special relativity.
|
[
{
"created": "Thu, 17 Dec 1998 20:00:31 GMT",
"version": "v1"
},
{
"created": "Thu, 31 Dec 1998 19:36:08 GMT",
"version": "v2"
},
{
"created": "Wed, 20 Jan 1999 20:11:16 GMT",
"version": "v3"
}
] |
2008-11-26
|
[
[
"Coleman",
"Sidney",
""
],
[
"Glashow",
"Sheldon L.",
""
]
] |
We develop a perturbative framework with which to discuss departures from exact Lorentz invariance and explore their potentially observable ramifications. Tiny non-invariant terms introduced into the standard model Lagrangian are assumed to be renormalizable (dimension $\le 4$), invariant under $SU(3)\otimes SU(2)\otimes U(1)$ gauge transformations, and rotationally and translationally invariant in a preferred frame. There are a total of 46 independent TCP-even perturbations of this kind, all of which preserve anomaly cancellation. They define the energy-momentum eigenstates and their maximal attainable velocities in the high-energy limit. The effects of these perturbations increase rapidly with energy in the preferred frame, more rapidly than those of TCP-odd perturbations. Our analysis of Lorentz-violating kinematics reveals several striking new phenomena that are relevant both to cosmic-ray physics ({\it e.g.,} by undoing the GZK cutoff) and neutrino physics ({\it e.g.,} by generating novel types of neutrino oscillations). These may lead to new and sensitive high-energy tests of special relativity.
|
2404.16931
|
Moinul Hossain Rahat
|
Bowen Fu, Anish Ghoshal, Stephen F. King, and Moinul Hossain Rahat
|
Type-I two-Higgs-doublet model and gravitational waves from domain walls
bounded by strings
|
20 pages, 4 figures
| null | null | null |
hep-ph astro-ph.CO
|
http://creativecommons.org/licenses/by/4.0/
|
The spontaneous breaking of a $U(1)$ symmetry via an intermediate discrete
symmetry may yield a hybrid topological defect of "domain walls bounded by
cosmic strings". The decay of this defect network leads to a unique
gravitational wave signal spanning many orders in observable frequencies, that
can be distinguished from signals generated by other sources. We investigate
the production of gravitational waves from this mechanism in the context of the
type-I two-Higgs-doublet model extended by a $U(1)_R$ symmetry, that
simultaneously accommodates the seesaw mechanism, anomaly cancellation, and
eliminates flavour-changing neutral currents. The gravitational wave spectrum
produced by the string-bounded-wall network can be detected for $U(1)_R$
breaking scale from $10^{12}$ to $10^{15}$ GeV in forthcoming interferometers
including LISA and Einstein Telescope, with a distinctive $f^{3}$ slope and
inflexion in the frequency range between microhertz and hertz.
|
[
{
"created": "Thu, 25 Apr 2024 18:00:02 GMT",
"version": "v1"
}
] |
2024-04-29
|
[
[
"Fu",
"Bowen",
""
],
[
"Ghoshal",
"Anish",
""
],
[
"King",
"Stephen F.",
""
],
[
"Rahat",
"Moinul Hossain",
""
]
] |
The spontaneous breaking of a $U(1)$ symmetry via an intermediate discrete symmetry may yield a hybrid topological defect of "domain walls bounded by cosmic strings". The decay of this defect network leads to a unique gravitational wave signal spanning many orders in observable frequencies, that can be distinguished from signals generated by other sources. We investigate the production of gravitational waves from this mechanism in the context of the type-I two-Higgs-doublet model extended by a $U(1)_R$ symmetry, that simultaneously accommodates the seesaw mechanism, anomaly cancellation, and eliminates flavour-changing neutral currents. The gravitational wave spectrum produced by the string-bounded-wall network can be detected for $U(1)_R$ breaking scale from $10^{12}$ to $10^{15}$ GeV in forthcoming interferometers including LISA and Einstein Telescope, with a distinctive $f^{3}$ slope and inflexion in the frequency range between microhertz and hertz.
|
hep-ph/9511216
|
Tanmay Vachaspati
|
Hong Liu and Tanmay Vachaspati
|
Perturbed Electroweak Strings and Fermion Zero Modes
|
17 pages + 1 figure; RevTeX
|
Nucl.Phys. B470 (1996) 176-194
|
10.1016/0550-3213(96)00158-7
|
CWRU-P14-95
|
hep-ph
| null |
The effect of perturbations of electroweak strings on quark zero modes is
studied in 2+1 and 3+1 dimensions. As first discovered by Naculich, it is found
that the bosonic perturbations that destabilize the string give a mass to the
zero modes and also lift their degeneracy. The effect of the zero modes on the
stability of the string is discussed qualitatively and we argue that the
fermionic vacuum instability found by Naculich should lead to a distortion of
the bosonic string but not be responsible for decay.
|
[
{
"created": "Thu, 2 Nov 1995 09:38:15 GMT",
"version": "v1"
}
] |
2015-06-25
|
[
[
"Liu",
"Hong",
""
],
[
"Vachaspati",
"Tanmay",
""
]
] |
The effect of perturbations of electroweak strings on quark zero modes is studied in 2+1 and 3+1 dimensions. As first discovered by Naculich, it is found that the bosonic perturbations that destabilize the string give a mass to the zero modes and also lift their degeneracy. The effect of the zero modes on the stability of the string is discussed qualitatively and we argue that the fermionic vacuum instability found by Naculich should lead to a distortion of the bosonic string but not be responsible for decay.
|
1812.10964
|
Tsutomu Ishikawa
|
Tsutomu Ishikawa, Katsumasa Nakayama, Kei Suzuki
|
Casimir effect for nucleon parity doublets
|
14 pages, 11 figures, 3 tables; published version
|
Phys. Rev. D 99, 054010 (2019)
|
10.1103/PhysRevD.99.054010
|
KEK-TH-2097
|
hep-ph hep-lat hep-th nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Finite-volume effects for the nucleon chiral partners are studied within the
framework of the parity-doublet model. Our model includes the vacuum energy
shift for nucleons, which is the Casimir effect. We find that for the
antiperiodic boundary the finite-volume effect leads to chiral symmetry
restoration, and the masses of the nucleon parity doublets degenerate. For the
periodic boundary, the chiral symmetry breaking is enhanced, and the masses of
the nucleons also increase. We also discuss the finite-temperature effect and
the dependence on the number of compactified spatial dimensions.
|
[
{
"created": "Fri, 28 Dec 2018 12:03:52 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Mar 2019 09:28:13 GMT",
"version": "v2"
}
] |
2019-03-27
|
[
[
"Ishikawa",
"Tsutomu",
""
],
[
"Nakayama",
"Katsumasa",
""
],
[
"Suzuki",
"Kei",
""
]
] |
Finite-volume effects for the nucleon chiral partners are studied within the framework of the parity-doublet model. Our model includes the vacuum energy shift for nucleons, which is the Casimir effect. We find that for the antiperiodic boundary the finite-volume effect leads to chiral symmetry restoration, and the masses of the nucleon parity doublets degenerate. For the periodic boundary, the chiral symmetry breaking is enhanced, and the masses of the nucleons also increase. We also discuss the finite-temperature effect and the dependence on the number of compactified spatial dimensions.
|
hep-ph/0112339
|
Okun Lev Borisovich
|
L. B. Okun
|
Cube or hypercube of natural units
|
7 pages, to be published in ``Multiple facets of quantization and
supersymmetry'', Michael Marinov Memorial Volume, Eds. M. Olshanetsky and A.
Vainshtein, World Scientific, 2002
| null |
10.1142/9789812777065_0036
| null |
hep-ph
| null |
Max Planck introduced four natural units: h, c, G, k. Only the first three of
them retained their status, representing the so called cube of theories, after
the theory of relativity and quantum mechanics were created and became the
pillars of physics. This short note is a little pebble on the tombstone of
Michael Samuilovich Marinov.
|
[
{
"created": "Thu, 27 Dec 2001 17:48:03 GMT",
"version": "v1"
}
] |
2016-11-23
|
[
[
"Okun",
"L. B.",
""
]
] |
Max Planck introduced four natural units: h, c, G, k. Only the first three of them retained their status, representing the so called cube of theories, after the theory of relativity and quantum mechanics were created and became the pillars of physics. This short note is a little pebble on the tombstone of Michael Samuilovich Marinov.
|
0807.0952
|
Tobias Gleim
|
Tobias Gleim
|
Similarities between neutrinos and Higgs bosons within a chiral
supersymmetric formulation
| null | null | null | null |
hep-ph hep-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Taking into account the helicity of a massless particle, which obeys a Dirac
equation and is exposed to an electromagnetic field, one soon arrives at a
Lagrangian containing a chiral supersymmetric operator. We can even achieve an
analogous result in case of an electroweak interaction. Then the Lagrangian
contains terms that look very similar to those usually being interpreted as
mass terms for the W and Z bosons appearing in models of spontaneous symmetry
breaking, but this time they are accompanied by neutrino fields instead of
Higgs fields. This invites us to a speculation that in the procedure of
spontaneous symmetry breaking, neutrinos could take on the role, which we
normally ascribe to the Higgs bosons.
|
[
{
"created": "Mon, 7 Jul 2008 06:03:45 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Jun 2011 19:25:18 GMT",
"version": "v2"
}
] |
2011-06-15
|
[
[
"Gleim",
"Tobias",
""
]
] |
Taking into account the helicity of a massless particle, which obeys a Dirac equation and is exposed to an electromagnetic field, one soon arrives at a Lagrangian containing a chiral supersymmetric operator. We can even achieve an analogous result in case of an electroweak interaction. Then the Lagrangian contains terms that look very similar to those usually being interpreted as mass terms for the W and Z bosons appearing in models of spontaneous symmetry breaking, but this time they are accompanied by neutrino fields instead of Higgs fields. This invites us to a speculation that in the procedure of spontaneous symmetry breaking, neutrinos could take on the role, which we normally ascribe to the Higgs bosons.
|
hep-ph/0307035
|
Roberto Bonciani
|
R. Bonciani (Freiburg U.), S. Catani (INFN, Florence), M. L. Mangano
(CERN) and P. Nason (INFN, Milan)
|
Sudakov resummation of multiparton QCD cross sections
|
13 pages, LaTeX
|
Phys.Lett. B575 (2003) 268-278
|
10.1016/j.physletb.2003.09.068
|
CERN-TH/2003-125, Bicocca-FT-03-17
|
hep-ph
| null |
We present the general expressions for the resummation, up to next-to-leading
logarithmic accuracy, of Sudakov-type logarithms in processes with an
arbirtrary number of hard-scattering partons. These results document the
formulae used by the authors in several previous phenomenological studies. The
resummation formulae presented here, which are valid for phase-space
factorizable observables, determine the resummation correction in a
process-independent fashion. All process dependence is encoded in the colour
and flavour structure of the leading order and virtual one-loop amplitudes, and
in Sudakov weights associated to the cross section kinematics. We explicitly
illustrate the application to the case of Drell--Yan and prompt-photon
production.
|
[
{
"created": "Wed, 2 Jul 2003 15:31:47 GMT",
"version": "v1"
}
] |
2010-04-05
|
[
[
"Bonciani",
"R.",
"",
"Freiburg U."
],
[
"Catani",
"S.",
"",
"INFN, Florence"
],
[
"Mangano",
"M. L.",
"",
"CERN"
],
[
"Nason",
"P.",
"",
"INFN, Milan"
]
] |
We present the general expressions for the resummation, up to next-to-leading logarithmic accuracy, of Sudakov-type logarithms in processes with an arbirtrary number of hard-scattering partons. These results document the formulae used by the authors in several previous phenomenological studies. The resummation formulae presented here, which are valid for phase-space factorizable observables, determine the resummation correction in a process-independent fashion. All process dependence is encoded in the colour and flavour structure of the leading order and virtual one-loop amplitudes, and in Sudakov weights associated to the cross section kinematics. We explicitly illustrate the application to the case of Drell--Yan and prompt-photon production.
|
hep-ph/9810236
|
Harald W. Griesshammer
|
H. W. Griesshammer (U of Washington)
|
The Soft R\'egime and \beta Function of NRQCD
|
6 pages LaTeX2e, uses feynmp to generate 5 drawings in 1 figure and 1
table. Necessary metapost-files included. Talk presented at the
``Euroconference QCD '98'' in Montpellier, France, 2nd -- 8th July 1998 (to
appear in Nucl. Phys. B (Proc. Suppl.)), and at the conference ``Quark
Confinement and the Hadron Spectrum III'' at TJNL, Newport News, USA, 8th --
12th June 1998 (to be published in the proceedings)
|
Nucl.Phys.Proc.Suppl. 74 (1999) 205-208
|
10.1016/S0920-5632(99)00163-2
|
NT@UW-98-23
|
hep-ph
| null |
Progress towards a complete velocity power counting in non-relativistic
effective field theories, especially NRQCD, is motivated and summarised.
|
[
{
"created": "Fri, 2 Oct 1998 23:01:04 GMT",
"version": "v1"
}
] |
2009-10-31
|
[
[
"Griesshammer",
"H. W.",
"",
"U of Washington"
]
] |
Progress towards a complete velocity power counting in non-relativistic effective field theories, especially NRQCD, is motivated and summarised.
|
hep-ph/0507221
|
Andrei Kataev
|
A.L.Kataev
|
The relations between Bjorken polarized, Bjorken unpolarized and
Gross--Llewellyn Smith sum rules
|
Talk at WG2 "Neutrino scattering physics" of 7th Int. Workshop on
Neutrino Factories and Superbeams: NUFACT05, Frascati, June 20-June 26, 2005,
submitted to the Proceedings; 2 pages, LaTeX
| null |
10.1016/j.nuclphysbps.2006.02.069
| null |
hep-ph
| null |
New relations between Bjorken polarized, Bjorken unpolarized and
Gross-Llewellyn Smith sum rules are desribed. These relations are valid in the
region, where both perturbative series and the series in power-suppressed
$1/Q^2$-terms do not yet mahifest the features of asymptotic expansions. The
experimentally based considerations support these relations which may surve as
the guide for possible in future measurements of the Bjorken unpolarized sum
rule at Neutrino Factories.
|
[
{
"created": "Tue, 19 Jul 2005 10:06:54 GMT",
"version": "v1"
}
] |
2009-11-11
|
[
[
"Kataev",
"A. L.",
""
]
] |
New relations between Bjorken polarized, Bjorken unpolarized and Gross-Llewellyn Smith sum rules are desribed. These relations are valid in the region, where both perturbative series and the series in power-suppressed $1/Q^2$-terms do not yet mahifest the features of asymptotic expansions. The experimentally based considerations support these relations which may surve as the guide for possible in future measurements of the Bjorken unpolarized sum rule at Neutrino Factories.
|
2204.11269
|
Alexey A. Petrov
|
Alexey A Petrov
|
Glueball-meson molecules
|
5 pages, 1 figure; title changed, minor changes to the text, replaced
to match the published version
|
Phys. Lett. B 843 (2023) 138030
|
10.1016/j.physletb.2023.138030
|
WSU-HEP-2202, FERMILAB-PUB-22-353-T-V
|
hep-ph hep-ex nucl-ex
|
http://creativecommons.org/licenses/by/4.0/
|
Experimental searches for pure glueball states have proven challenging and so
far yielded no results. This is believed to occur because glueballs mix with
the ordinary $q\bar q$ states with the same quantum numbers. We will discuss an
alternative mechanism, the formation of the glueball-meson molecular states. We
will argue that the wave functions of already observed excited meson states may
contain a significant part due to such molecular states. We discuss the
phenomenology of glueball-meson molecules and comment on a possible charmless
component of the $XYZ$ states.
|
[
{
"created": "Sun, 24 Apr 2022 13:13:06 GMT",
"version": "v1"
},
{
"created": "Sun, 25 Jun 2023 21:42:49 GMT",
"version": "v2"
}
] |
2023-06-27
|
[
[
"Petrov",
"Alexey A",
""
]
] |
Experimental searches for pure glueball states have proven challenging and so far yielded no results. This is believed to occur because glueballs mix with the ordinary $q\bar q$ states with the same quantum numbers. We will discuss an alternative mechanism, the formation of the glueball-meson molecular states. We will argue that the wave functions of already observed excited meson states may contain a significant part due to such molecular states. We discuss the phenomenology of glueball-meson molecules and comment on a possible charmless component of the $XYZ$ states.
|
1908.00561
|
Juan M. Torres-Rincon
|
Stefano Carignano, Cristina Manuel and Juan M. Torres-Rincon
|
Chiral kinetic theory from the on-shell effective theory: derivation of
collision terms
|
36 pages, 2 figures, title and abstract modified, version largely
extended with more details and discussions, results and conclusions unchanged
|
Phys. Rev. D 102, 016003 (2020)
|
10.1103/PhysRevD.102.016003
| null |
hep-ph hep-th nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We show that the on-shell effective theory (OSEFT) is the quantum field
theory counterpart of a Foldy-Wouthuysen diagonalization of relativistic
quantum mechanics for massless fermions. Thus, it is free of the Zitterbewegung
oscillations that would yield an ill-defined meaning to the semiclassical
transport approach at short distances if derived from the pure Dirac picture.
We present a detailed derivation of the collision terms in the chiral kinetic
theory using the OSEFT. Collision integrals are derived up to order 1/E, where
E is the energy of an on-shell fermion. At this order, the collision terms
depends on the spin tensor of the fermion, and in the presence of chiral
imbalance, it describes how a massless fermion of a given helicity interacts
differently with the transverse photons of different circular polarization. In
order to back up our results, we check that they allow us to reproduce the
fermion decay rate in an ultradegenerate plasma with a chiral imbalance
computed directly from QED.
|
[
{
"created": "Thu, 1 Aug 2019 18:07:14 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Feb 2020 17:23:41 GMT",
"version": "v2"
}
] |
2020-07-15
|
[
[
"Carignano",
"Stefano",
""
],
[
"Manuel",
"Cristina",
""
],
[
"Torres-Rincon",
"Juan M.",
""
]
] |
We show that the on-shell effective theory (OSEFT) is the quantum field theory counterpart of a Foldy-Wouthuysen diagonalization of relativistic quantum mechanics for massless fermions. Thus, it is free of the Zitterbewegung oscillations that would yield an ill-defined meaning to the semiclassical transport approach at short distances if derived from the pure Dirac picture. We present a detailed derivation of the collision terms in the chiral kinetic theory using the OSEFT. Collision integrals are derived up to order 1/E, where E is the energy of an on-shell fermion. At this order, the collision terms depends on the spin tensor of the fermion, and in the presence of chiral imbalance, it describes how a massless fermion of a given helicity interacts differently with the transverse photons of different circular polarization. In order to back up our results, we check that they allow us to reproduce the fermion decay rate in an ultradegenerate plasma with a chiral imbalance computed directly from QED.
|
2404.08591
|
Tom Steele
|
Siyuan Li, T.G. Steele, J. Ho, R. Raza, K. Williams, R.T. Kleiv
|
QCD bounds on leading-order hadronic vacuum polarization contributions
to the muon anomalous magnetic moment
|
17 pages, 4 figures. v2 contains extended analysis and discussion
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
QCD bounds on the leading-order (LO) hadronic vacuum polarization (HVP)
contribution to the anomalous magnetic moment of the muon
($a_\mu^{\mathrm{HVP,LO}}$, $a_\mu=\left(g-2\right)_\mu/2$) are determined by
imposing H\"older inequalities and related inequality constraints on systems of
Finite-Energy QCD sum-rules. This novel methodology is complementary to lattice
QCD and data-driven approaches to determining $a_\mu^{\mathrm{HVP,LO}}$. For
the light-quark ($u,d,s$) contributions up to five-loop order in perturbation
theory in the chiral limit, LO in light-quark mass corrections, next-to-leading
order in dimension-four QCD condensates, and to LO in dimension-six QCD
condensates, we find that $\left(657.0\pm 34.8\right)\times 10^{-10}\leq
a_\mu^{\mathrm{HVP,LO}} \leq \left(788.4\pm 41.8\right)\times10^{-10}\,$,
bridging the range between lattice QCD and data-driven values.
|
[
{
"created": "Fri, 12 Apr 2024 16:39:29 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Jul 2024 16:00:41 GMT",
"version": "v2"
}
] |
2024-08-01
|
[
[
"Li",
"Siyuan",
""
],
[
"Steele",
"T. G.",
""
],
[
"Ho",
"J.",
""
],
[
"Raza",
"R.",
""
],
[
"Williams",
"K.",
""
],
[
"Kleiv",
"R. T.",
""
]
] |
QCD bounds on the leading-order (LO) hadronic vacuum polarization (HVP) contribution to the anomalous magnetic moment of the muon ($a_\mu^{\mathrm{HVP,LO}}$, $a_\mu=\left(g-2\right)_\mu/2$) are determined by imposing H\"older inequalities and related inequality constraints on systems of Finite-Energy QCD sum-rules. This novel methodology is complementary to lattice QCD and data-driven approaches to determining $a_\mu^{\mathrm{HVP,LO}}$. For the light-quark ($u,d,s$) contributions up to five-loop order in perturbation theory in the chiral limit, LO in light-quark mass corrections, next-to-leading order in dimension-four QCD condensates, and to LO in dimension-six QCD condensates, we find that $\left(657.0\pm 34.8\right)\times 10^{-10}\leq a_\mu^{\mathrm{HVP,LO}} \leq \left(788.4\pm 41.8\right)\times10^{-10}\,$, bridging the range between lattice QCD and data-driven values.
|
0707.2631
|
JingWu Li
|
Jing-Wu Li, Dong-Sheng Du
|
The study of $B\to J/\Psi \eta^{(\prime)}$ decays and determination of
$\eta-\eta^{\prime}$ mixing angle
|
16pages,4figures
|
Phys.Rev.D78:074030,2008
|
10.1103/PhysRevD.78.074030
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We study $B\to J/\Psi \eta^{(\prime)}$ decays and suggest two methods to
determine the $\eta-\eta^{\prime}$ mixing angle. We calculate not only the
factorizable contribution in QCD facorization scheme but also the
nonfactorizable hard spectator corrections in pQCD approach. We get the
branching ratio of $B\to J/\Psi \eta$ which is consistent with recent
experimental data and predict the branching ratio of $B\to J/\Psi
\eta^{\prime}$ to be $7.59\times 10^{-6}$. Two methods for determining
$\eta-\eta^{\prime}$ mixing angle are suggested in this paper. For the first
method, we get the $\eta-\eta^{\prime}$ mixing angle to be about
$-13.1^{\circ}$, which is in consistency with others in the literature. The
second method depends on less parameters so can be used to determine the
$\eta-\eta^{\prime}$ mixing angle with better accuracy but needs, as an input,
the branching ratio for $B\to J/\Psi \eta^{\prime}$which should be measured in
the near future.
|
[
{
"created": "Wed, 18 Jul 2007 04:24:33 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Jul 2007 06:40:37 GMT",
"version": "v2"
},
{
"created": "Wed, 8 Apr 2009 11:04:31 GMT",
"version": "v3"
}
] |
2016-09-08
|
[
[
"Li",
"Jing-Wu",
""
],
[
"Du",
"Dong-Sheng",
""
]
] |
We study $B\to J/\Psi \eta^{(\prime)}$ decays and suggest two methods to determine the $\eta-\eta^{\prime}$ mixing angle. We calculate not only the factorizable contribution in QCD facorization scheme but also the nonfactorizable hard spectator corrections in pQCD approach. We get the branching ratio of $B\to J/\Psi \eta$ which is consistent with recent experimental data and predict the branching ratio of $B\to J/\Psi \eta^{\prime}$ to be $7.59\times 10^{-6}$. Two methods for determining $\eta-\eta^{\prime}$ mixing angle are suggested in this paper. For the first method, we get the $\eta-\eta^{\prime}$ mixing angle to be about $-13.1^{\circ}$, which is in consistency with others in the literature. The second method depends on less parameters so can be used to determine the $\eta-\eta^{\prime}$ mixing angle with better accuracy but needs, as an input, the branching ratio for $B\to J/\Psi \eta^{\prime}$which should be measured in the near future.
|
1312.1596
|
Shunzo Kumano
|
H. Kawamura and S. Kumano
|
Tomography of exotic hadrons in high-energy exclusive processes
|
12 pages, 11 figures, Phys. Rev. D in press
| null |
10.1103/PhysRevD.89.054007
|
KEK-TH-1589, J-PARC-TH-0021
|
hep-ph hep-ex nucl-ex nucl-th
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We investigated the possibility of determining internal structure of exotic
hadrons by using high-energy reaction processes, where quarks and gluons are
appropriate degrees of freedom. In particular, it should be valuable to
investigate the high-energy exclusive processes which include generalized
parton distributions (GPDs) and generalized distribution amplitudes (GDAs). The
GPDs and GDAs contain momentum distributions of partons and form factors. We
found that the exotic nature appears in momentum distributions of quarks as
suggested by the constituent-counting rule and in the form factors associated
with exotic hadron sizes and the number of constituents. Transition GPDs to
exotic hadrons could probe such exotic signatures. We also propose that these
exotic signatures should be found in exclusive production processes of exotic
hadrons from gamma^* gamma in electron-positron annihilation. For example, the
GDAs contain information on a time-like form factor of the energy-momentum
tensor of a hadron h. We show that the cross section of e gamma -> e+hbar h is
sensitive to the exotic signature by looking at the hbar h invariant-mass
dependence by taking light hadrons, h=f_0 (980) and a_0 (980). From such GDA
measurements, the tomography of exotic hadrons becomes possible, for example,
by Belle and BaBar experiments and by future linear collider.
|
[
{
"created": "Thu, 5 Dec 2013 16:07:16 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Jan 2014 02:17:54 GMT",
"version": "v2"
}
] |
2015-06-18
|
[
[
"Kawamura",
"H.",
""
],
[
"Kumano",
"S.",
""
]
] |
We investigated the possibility of determining internal structure of exotic hadrons by using high-energy reaction processes, where quarks and gluons are appropriate degrees of freedom. In particular, it should be valuable to investigate the high-energy exclusive processes which include generalized parton distributions (GPDs) and generalized distribution amplitudes (GDAs). The GPDs and GDAs contain momentum distributions of partons and form factors. We found that the exotic nature appears in momentum distributions of quarks as suggested by the constituent-counting rule and in the form factors associated with exotic hadron sizes and the number of constituents. Transition GPDs to exotic hadrons could probe such exotic signatures. We also propose that these exotic signatures should be found in exclusive production processes of exotic hadrons from gamma^* gamma in electron-positron annihilation. For example, the GDAs contain information on a time-like form factor of the energy-momentum tensor of a hadron h. We show that the cross section of e gamma -> e+hbar h is sensitive to the exotic signature by looking at the hbar h invariant-mass dependence by taking light hadrons, h=f_0 (980) and a_0 (980). From such GDA measurements, the tomography of exotic hadrons becomes possible, for example, by Belle and BaBar experiments and by future linear collider.
|
1107.1501
|
Amitabha Lahiri
|
Amitabha Lahiri and Debmalya Mukhopadhyay
|
Unitarity in $WW \to WW$ elastic scattering in topologically massive
SU(2) gauge theory
|
RevTeX 4, 7 pages, 8 figures;v2: refs and discussion added, typo in
eq.(20) corrected; v3: title and abstract changed, many sentences rephrased,
calculations and main result unchanged
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider the elastic scattering of longitudinally polarized gauge bosons
in an SU(2) generalization of topologically massive gauge theory in four
dimensions. We show that the amplitude remains finite at large $s$, even though
the theory does not contain a Higgs particle, in contradiction to common lore.
|
[
{
"created": "Thu, 7 Jul 2011 20:00:17 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Sep 2011 08:40:00 GMT",
"version": "v2"
},
{
"created": "Tue, 8 Oct 2013 12:14:17 GMT",
"version": "v3"
}
] |
2015-03-19
|
[
[
"Lahiri",
"Amitabha",
""
],
[
"Mukhopadhyay",
"Debmalya",
""
]
] |
We consider the elastic scattering of longitudinally polarized gauge bosons in an SU(2) generalization of topologically massive gauge theory in four dimensions. We show that the amplitude remains finite at large $s$, even though the theory does not contain a Higgs particle, in contradiction to common lore.
|
1301.1736
|
Chi-Sing Lam
|
C. S. Lam
|
Horizontal Symmetries $\Delta(150)$ and $\Delta(600)$
|
version to appear in Phys. Rev. D
| null |
10.1103/PhysRevD.87.053012
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
Using group theory of mixing to examine all finite subgroups of SU(3) with an
order less than 512, we found recently that only the group $\Delta(150)$ can
give rise to a correct reactor angle $\th_{13}$ of neutrino mixing without any
free parameter. It predicts $\sin^22\th_{13}=0.11$ and a sub-maximal
atmospheric angle with $\sin^22\th_{23}=0.94$, in good agreement with
experiment. The solar angle $\th_{12}$, the CP phase $\d$, and the neutrino
masses $m_i$ are left as free parameters. In this article we provide more
details of this case, discuss possible gain and loss by introducing
right-handed symmetries, and/or valons to construct dynamical models. A simple
model is discussed where the solar angle agrees with experiment, and all its
mixing parameters can be obtained from the group $\Delta(600)$ by symmetry
alone. The promotion of $\Delta(150)$ to $\Delta(600)$ is on the one hand
analogous to the promotion of $S_3$ to $S_4$ in the presence of tribimaximal
mixing, and on the other hand similar to the extension from $A_4$ to $S_4$ in
that case.
|
[
{
"created": "Wed, 9 Jan 2013 02:13:50 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Feb 2013 01:04:57 GMT",
"version": "v2"
}
] |
2015-06-12
|
[
[
"Lam",
"C. S.",
""
]
] |
Using group theory of mixing to examine all finite subgroups of SU(3) with an order less than 512, we found recently that only the group $\Delta(150)$ can give rise to a correct reactor angle $\th_{13}$ of neutrino mixing without any free parameter. It predicts $\sin^22\th_{13}=0.11$ and a sub-maximal atmospheric angle with $\sin^22\th_{23}=0.94$, in good agreement with experiment. The solar angle $\th_{12}$, the CP phase $\d$, and the neutrino masses $m_i$ are left as free parameters. In this article we provide more details of this case, discuss possible gain and loss by introducing right-handed symmetries, and/or valons to construct dynamical models. A simple model is discussed where the solar angle agrees with experiment, and all its mixing parameters can be obtained from the group $\Delta(600)$ by symmetry alone. The promotion of $\Delta(150)$ to $\Delta(600)$ is on the one hand analogous to the promotion of $S_3$ to $S_4$ in the presence of tribimaximal mixing, and on the other hand similar to the extension from $A_4$ to $S_4$ in that case.
|
1601.00386
|
Takaaki Nomura
|
Takaaki Nomura, Hiroshi Okada
|
Four-loop Neutrino Model Inspired by Diphoton Excess at 750 GeV
|
15 pages, 3 figures, 1 table, accepted for publication in phys. Lett.
B
| null |
10.1016/j.physletb.2016.02.022
|
KIAS-P16004
|
hep-ph hep-ex
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We propose a four-loop induced radiative neutrino mass model inspired by the
diphoton excess at 750 GeV recently reported by ATLAS and CMS, in which a
sizable diphoton excess is obtained via photon fusion introducing multi
doubly-charged scalar bosons. Also we discuss the muon anomalous magnetic
moment, and a dark matter candidate. The main process to explain the observed
relic density relies on the final state of the new particle at 750 GeV. Finally
we show the numerical results and obtain allowed region of several physical
values in our model.
|
[
{
"created": "Mon, 4 Jan 2016 06:05:04 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Feb 2016 14:32:03 GMT",
"version": "v2"
}
] |
2016-02-24
|
[
[
"Nomura",
"Takaaki",
""
],
[
"Okada",
"Hiroshi",
""
]
] |
We propose a four-loop induced radiative neutrino mass model inspired by the diphoton excess at 750 GeV recently reported by ATLAS and CMS, in which a sizable diphoton excess is obtained via photon fusion introducing multi doubly-charged scalar bosons. Also we discuss the muon anomalous magnetic moment, and a dark matter candidate. The main process to explain the observed relic density relies on the final state of the new particle at 750 GeV. Finally we show the numerical results and obtain allowed region of several physical values in our model.
|
hep-ph/0307250
|
Otto Kong
|
O.C.W. Kong (Nat'l Central U., Taiwan)
|
A Completed Chiral Fermionic Sector Model with Little Higgs
|
10 pages in Revtex, no figure; the couple of lines on the gauge boson
sectro was not carefully written and wrong -- they are corrected
| null | null |
NCU-HEP-k009
|
hep-ph
| null |
The Standard Model has some intrinsic beauty in the sector of fermions and
gauge bosons. Its scalar sector, though minimal, is however haunted by the
hierarchy problem. The fermionic spectrum also have two major problems, the
flavor problem with its fundamental notion about why there are three families,
and the phenomenological limitation of massless neutrinos. We present here a
completed chiral fermionic sector model, based on a little Higgs model, that
has the plausible potential of addressing all these problems of the SM at an
accessible energy scale, and comment briefly on its phenomenology. The focus
here is not on the little Higgs part, but rather on the electroweak quarks and
leptons from the model, which of course from an important part of the full
model.
|
[
{
"created": "Sat, 19 Jul 2003 15:34:52 GMT",
"version": "v1"
},
{
"created": "Sun, 3 Aug 2003 05:17:18 GMT",
"version": "v2"
}
] |
2007-05-23
|
[
[
"Kong",
"O. C. W.",
"",
"Nat'l Central U., Taiwan"
]
] |
The Standard Model has some intrinsic beauty in the sector of fermions and gauge bosons. Its scalar sector, though minimal, is however haunted by the hierarchy problem. The fermionic spectrum also have two major problems, the flavor problem with its fundamental notion about why there are three families, and the phenomenological limitation of massless neutrinos. We present here a completed chiral fermionic sector model, based on a little Higgs model, that has the plausible potential of addressing all these problems of the SM at an accessible energy scale, and comment briefly on its phenomenology. The focus here is not on the little Higgs part, but rather on the electroweak quarks and leptons from the model, which of course from an important part of the full model.
|
0908.3811
|
Sascha Vogel
|
S. Vogel, J. Aichelin, M. Bleicher
|
High $p_T$ resonances as a possibility to explore hot and dense nuclear
matter
|
4 pages, 6 figures
|
Phys.Rev.C82:014907,2010
|
10.1103/PhysRevC.82.014907
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
One of the fundamental objectives of experiments with ultrarelativistic heavy
ions is to explore strongly interacting matter at high density and high
temperature. In this investigation we study in particular the information which
can be obtained by analyzing baryonic and mesonic resonances. The decay
products of these resonances carry information on the resonances properties at
the space time point of their decay. We especially investigate the percentage
of reconstructable resonances as a function of density for heavy ion collisions
in the energy range between $E_{lab}$ = 30 AGeV and $\sqrt{s}$ = 200 AGeV, the
energy domain between the future FAIR facility and the present RHIC collider.
|
[
{
"created": "Wed, 26 Aug 2009 13:10:08 GMT",
"version": "v1"
}
] |
2014-11-20
|
[
[
"Vogel",
"S.",
""
],
[
"Aichelin",
"J.",
""
],
[
"Bleicher",
"M.",
""
]
] |
One of the fundamental objectives of experiments with ultrarelativistic heavy ions is to explore strongly interacting matter at high density and high temperature. In this investigation we study in particular the information which can be obtained by analyzing baryonic and mesonic resonances. The decay products of these resonances carry information on the resonances properties at the space time point of their decay. We especially investigate the percentage of reconstructable resonances as a function of density for heavy ion collisions in the energy range between $E_{lab}$ = 30 AGeV and $\sqrt{s}$ = 200 AGeV, the energy domain between the future FAIR facility and the present RHIC collider.
|
2406.06861
|
Ye-Ling Zhou
|
Gao-Xiang Fang and Ye-Ling Zhou
|
Exploring flavour space of an economical SU(5) GUT in future proton
decay measurements
|
21 pages, 8 figures
| null | null | null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We discuss the potential of future proton decay experiments on the
exploration of the flavour space of grand unification. We focus on an
economical SU(5) grand unified model (GUT) with the fermion sector extended by
including only one copy of 24-plet. Neutrino masses are generated via
type-(I+III) seesaw mechanism with the lightest neutrino massless. Gauge
unification requires masses of fermions in the 24-plet to be hierarchical, in
particular, the electroweak singlet and triplet heavy leptons to be around the
canonical seesaw scale and TeV scale, respectively. We address how extra
parameters in the flavour space which cannot be touched in flavour measurements
can be tested by a multi-channel analysis in future proton decay measurements.
|
[
{
"created": "Tue, 11 Jun 2024 00:30:36 GMT",
"version": "v1"
}
] |
2024-06-12
|
[
[
"Fang",
"Gao-Xiang",
""
],
[
"Zhou",
"Ye-Ling",
""
]
] |
We discuss the potential of future proton decay experiments on the exploration of the flavour space of grand unification. We focus on an economical SU(5) grand unified model (GUT) with the fermion sector extended by including only one copy of 24-plet. Neutrino masses are generated via type-(I+III) seesaw mechanism with the lightest neutrino massless. Gauge unification requires masses of fermions in the 24-plet to be hierarchical, in particular, the electroweak singlet and triplet heavy leptons to be around the canonical seesaw scale and TeV scale, respectively. We address how extra parameters in the flavour space which cannot be touched in flavour measurements can be tested by a multi-channel analysis in future proton decay measurements.
|
hep-ph/0106149
|
Cecilia Lunardini
|
C.Lunardini, A.Yu.Smirnov
|
Supernova neutrinos: Earth matter effects and neutrino mass spectrum
|
LaTeX, 54 pages, 21 figures. Slight modifications in the discussion
on the identification of Earth effects, minor changes in the figures and in
the notation, typos corrected, references added
|
Nucl.Phys. B616 (2001) 307-348
|
10.1016/S0550-3213(01)00468-0
| null |
hep-ph astro-ph
| null |
We perform a detailed study of the Earth matter effects on supernova
neutrinos. The dependences of these effects on the properties of the original
neutrino fluxes, on the trajectory of the neutrinos inside the Earth and on the
oscillation parameters are described. We show that, for a large fraction (60 %)
of the possible arrival times of the signal, the neutrino flux crosses a
substantial amount of the matter of the Earth at least for one of the existing
detectors. For oscillation parameters from the LMA solution of the solar
neutrino problem the Earth matter effect consists in an oscillatory modulation
of the $\barnue$ and/or $\nu_e$ energy spectra. The relative deviation with
respect to the undistorted spectra can be as large as 20-30 % for E> 20 MeV and
70-100 % for E> 40 MeV. For parameters from the
SMA and LOW solutions the effect is localized at low energies (E<10 MeV) and
is not larger than 10 %. The Earth matter effects can be revealed (i) by the
observation of oscillatory distortions of the energy spectra in a single
experiment and (ii) by the comparison between the spectra at different
detectors. For a supernova at distance D=10 Kpc, comparing the results of
SuperKamiokande (SK), SNO and LVD experiments one can establish the effect at
(2-3) \sigma level, whereas larger statistical significance ((4-5) \sigma) is
obtained if two experiments of SK-size or larger are available. Studies of the
Earth matter effect will select or confirm the solution of the solar neutrino
problem, probe the mixing U_{e 3} and identify the hierarchy of the neutrino
mass spectrum.
|
[
{
"created": "Thu, 14 Jun 2001 13:10:21 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jun 2001 15:50:43 GMT",
"version": "v2"
}
] |
2016-09-06
|
[
[
"Lunardini",
"C.",
""
],
[
"Smirnov",
"A. Yu.",
""
]
] |
We perform a detailed study of the Earth matter effects on supernova neutrinos. The dependences of these effects on the properties of the original neutrino fluxes, on the trajectory of the neutrinos inside the Earth and on the oscillation parameters are described. We show that, for a large fraction (60 %) of the possible arrival times of the signal, the neutrino flux crosses a substantial amount of the matter of the Earth at least for one of the existing detectors. For oscillation parameters from the LMA solution of the solar neutrino problem the Earth matter effect consists in an oscillatory modulation of the $\barnue$ and/or $\nu_e$ energy spectra. The relative deviation with respect to the undistorted spectra can be as large as 20-30 % for E> 20 MeV and 70-100 % for E> 40 MeV. For parameters from the SMA and LOW solutions the effect is localized at low energies (E<10 MeV) and is not larger than 10 %. The Earth matter effects can be revealed (i) by the observation of oscillatory distortions of the energy spectra in a single experiment and (ii) by the comparison between the spectra at different detectors. For a supernova at distance D=10 Kpc, comparing the results of SuperKamiokande (SK), SNO and LVD experiments one can establish the effect at (2-3) \sigma level, whereas larger statistical significance ((4-5) \sigma) is obtained if two experiments of SK-size or larger are available. Studies of the Earth matter effect will select or confirm the solution of the solar neutrino problem, probe the mixing U_{e 3} and identify the hierarchy of the neutrino mass spectrum.
|
1011.6647
|
John M. Campbell
|
Simon Badger, John M. Campbell and R. K. Ellis
|
QCD corrections to the hadronic production of a heavy quark pair and a
W-boson including decay correlations
|
45 pages, 17 figures
|
JHEP 1103:027,2011
|
10.1007/JHEP03(2011)027
|
FERMILAB-Pub-10-482-T
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We perform an analytic calculation of the one-loop amplitude for the W-boson
mediated process 0 \to d u-bar Q Q-bar l-bar l, retaining the mass for the
quark Q. The momentum of each of the massive quarks is expressed as the sum of
two massless momenta and the corresponding heavy quark spinor is expressed as a
sum of two massless spinors. Using a special choice for the heavy quark spinors
we obtain analytic expressions for the one-loop amplitudes which are amenable
to fast numerical evaluation. The full next-to-leading order (NLO) calculation
of hadron+hadron \to W(\to e nu) b b-bar with massive b-quarks is included in
the program MCFM. A comparison is performed with previous published work.
|
[
{
"created": "Tue, 30 Nov 2010 19:36:41 GMT",
"version": "v1"
}
] |
2011-03-18
|
[
[
"Badger",
"Simon",
""
],
[
"Campbell",
"John M.",
""
],
[
"Ellis",
"R. K.",
""
]
] |
We perform an analytic calculation of the one-loop amplitude for the W-boson mediated process 0 \to d u-bar Q Q-bar l-bar l, retaining the mass for the quark Q. The momentum of each of the massive quarks is expressed as the sum of two massless momenta and the corresponding heavy quark spinor is expressed as a sum of two massless spinors. Using a special choice for the heavy quark spinors we obtain analytic expressions for the one-loop amplitudes which are amenable to fast numerical evaluation. The full next-to-leading order (NLO) calculation of hadron+hadron \to W(\to e nu) b b-bar with massive b-quarks is included in the program MCFM. A comparison is performed with previous published work.
|
hep-ph/9809293
|
Ferenc Csikor
|
F. Csikor, Z. Fodor, J. Heitger
|
Where does the hot electroweak phase transition end?
|
LATTICE98(electroweak), presented by Z. Fodor. Latex, 3 pages, 3 figu
res. Comment line changed
|
Nucl.Phys.Proc.Suppl. 73 (1999) 659-661
|
10.1016/S0920-5632(99)85166-4
|
ITP-Budapest 545
|
hep-ph hep-lat
| null |
We give the nonperturbative phase diagram of the four-dimensional hot
electroweak phase transition. A systematic extrapolation $a \to 0$ is done. Our
results show that the finite temperature SU(2)-Higgs phase transition is of
first order for Higgs-boson masses $m_H<66.5 \pm 1.4$ GeV. The full
four-dimensional result agrees completely with that of the dimensional
reduction approximation. This fact is of particular importance, because it
indicates that the fermionic sector of the Standard Model (SM) can be included
perturbatively. We obtain that the Higgs-boson endpoint mass in the SM is $72.4
\pm 1.7$ GeV. Taking into account the LEP Higgs-boson mass lower bound excludes
any electroweak phase transition in the SM.
|
[
{
"created": "Mon, 7 Sep 1998 20:41:18 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Sep 1998 12:53:54 GMT",
"version": "v2"
}
] |
2009-10-31
|
[
[
"Csikor",
"F.",
""
],
[
"Fodor",
"Z.",
""
],
[
"Heitger",
"J.",
""
]
] |
We give the nonperturbative phase diagram of the four-dimensional hot electroweak phase transition. A systematic extrapolation $a \to 0$ is done. Our results show that the finite temperature SU(2)-Higgs phase transition is of first order for Higgs-boson masses $m_H<66.5 \pm 1.4$ GeV. The full four-dimensional result agrees completely with that of the dimensional reduction approximation. This fact is of particular importance, because it indicates that the fermionic sector of the Standard Model (SM) can be included perturbatively. We obtain that the Higgs-boson endpoint mass in the SM is $72.4 \pm 1.7$ GeV. Taking into account the LEP Higgs-boson mass lower bound excludes any electroweak phase transition in the SM.
|
hep-ph/0103309
|
Douglas Ross
|
M.A. Diaz, D.A. Ross
|
Prototype Graphs for radiative Corrections to Polarized Chargino or
Neutralino Production in Electron-Positron Annihilation
|
LATEX 38 pages, 26 figures
|
JHEP 0106:001,2001
|
10.1088/1126-6708/2001/06/001
|
CERN-TH/2001-071, UCCHEP/16-01
|
hep-ph
| null |
We present the contributions from all types of one-loop corrections to the
scattering amplitude for the pair production of polarized charginos or
neutralinos from polarized electron-positron annihilation. The contributions
are classified in terms of ``prototypes'' distinguished by the number of
particles inside the loops and their spins. The results are quoted in terms of
the Veltman-Passarino functions in terms of general couplings and internal
masses. The results can therefore be applied to any supersymmetric extension of
the Standard Model or indeed to any polarized fermion pair production process
in electron-positron annihilation.
|
[
{
"created": "Thu, 29 Mar 2001 06:41:20 GMT",
"version": "v1"
}
] |
2015-06-25
|
[
[
"Diaz",
"M. A.",
""
],
[
"Ross",
"D. A.",
""
]
] |
We present the contributions from all types of one-loop corrections to the scattering amplitude for the pair production of polarized charginos or neutralinos from polarized electron-positron annihilation. The contributions are classified in terms of ``prototypes'' distinguished by the number of particles inside the loops and their spins. The results are quoted in terms of the Veltman-Passarino functions in terms of general couplings and internal masses. The results can therefore be applied to any supersymmetric extension of the Standard Model or indeed to any polarized fermion pair production process in electron-positron annihilation.
|
1206.1076
|
Giulia Pancheri Dr.
|
Agnes Grau, Simone Pacetti, Giulia Pancheri and Yogendra N. Srivastava
|
Checks of asymptotia in pp elastic scattering at LHC
|
16 pages, 5 figures
| null |
10.1016/j.physletb.2012.06.058
| null |
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We parametrize TOTEM data for the elastic differential pp cross section at
sqrt(s)=7 TeV in terms of two exponentials with a relative phase. We employ two
previously derived sum rules for pp elastic scattering amplitude in impact
parameter space to check whether asymptotia has been reached at the LHC. A
detailed study of the TOTEM data for the elastic differential cross section at
sqrt(s)=7 TeV is made and it is shown that, within errors, the asymptotic sum
rules are satisfied at LHC. We propose to use this parametrization to study
forthcoming higher energy data.
|
[
{
"created": "Tue, 5 Jun 2012 21:30:00 GMT",
"version": "v1"
}
] |
2015-06-05
|
[
[
"Grau",
"Agnes",
""
],
[
"Pacetti",
"Simone",
""
],
[
"Pancheri",
"Giulia",
""
],
[
"Srivastava",
"Yogendra N.",
""
]
] |
We parametrize TOTEM data for the elastic differential pp cross section at sqrt(s)=7 TeV in terms of two exponentials with a relative phase. We employ two previously derived sum rules for pp elastic scattering amplitude in impact parameter space to check whether asymptotia has been reached at the LHC. A detailed study of the TOTEM data for the elastic differential cross section at sqrt(s)=7 TeV is made and it is shown that, within errors, the asymptotic sum rules are satisfied at LHC. We propose to use this parametrization to study forthcoming higher energy data.
|
1611.04932
|
Tommi Tenkanen
|
Tommi Alanne, Francesco Sannino, Tommi Tenkanen, Kimmo Tuominen
|
Inflation and pseudo-Goldstone Higgs boson
|
6 pages, 3 figures. v2: References and discussion added, matches the
published version
|
Phys. Rev. D 95, 035004 (2017)
|
10.1103/PhysRevD.95.035004
|
CP$^3$-Origins-2016-049 DNRF90 \& HIP-2016-32/TH
|
hep-ph astro-ph.CO
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
We consider inflation within a model framework where the Higgs boson arises
as a pseudo-Goldstone boson associated with the breaking of a global symmetry
at a scale significantly larger than the electroweak one. We show that in such
a model the scalar self-couplings can be parametrically suppressed and,
consequently, the non-minimal couplings to gravity can be of order one or less,
while the inflationary predictions of the model remain compatible with the
precision cosmological observations. Furthermore, in the model we study, the
existence of the electroweak scale is entirely due to the inflaton field. Our
model therefore suggests that inflation and low energy particle phenomenology
may be more entwined than assumed so far.
|
[
{
"created": "Tue, 15 Nov 2016 16:53:21 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Feb 2017 10:42:33 GMT",
"version": "v2"
}
] |
2017-02-15
|
[
[
"Alanne",
"Tommi",
""
],
[
"Sannino",
"Francesco",
""
],
[
"Tenkanen",
"Tommi",
""
],
[
"Tuominen",
"Kimmo",
""
]
] |
We consider inflation within a model framework where the Higgs boson arises as a pseudo-Goldstone boson associated with the breaking of a global symmetry at a scale significantly larger than the electroweak one. We show that in such a model the scalar self-couplings can be parametrically suppressed and, consequently, the non-minimal couplings to gravity can be of order one or less, while the inflationary predictions of the model remain compatible with the precision cosmological observations. Furthermore, in the model we study, the existence of the electroweak scale is entirely due to the inflaton field. Our model therefore suggests that inflation and low energy particle phenomenology may be more entwined than assumed so far.
|
2105.09271
|
Anke Biek\"otter
|
Anke Biek\"otter, Ka Wang Kwok and Benjamin D. Pecjak
|
Potential and limitations of machine-learning approaches to inclusive
$|V_{ub}|$ determinations
|
20 pages, 11 figures; v2: Final version published in JHEP
| null |
10.1007/JHEP01(2022)143
|
IPPP/20/104
|
hep-ph
|
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
|
The determination of $|V_{ub}|$ in inclusive semileptonic $B \to X_u \ell
\nu$ decays will be among the pivotal tasks of Belle II. In this paper we study
the potential and limitations of machine learning approaches that attempt to
reduce theory uncertainties by extending the experimentally accessible fiducial
region of the $B\to X_u \ell\nu$ signal into regions where the $B\to X_c
\ell\nu$ background is dominant. We find that a deep neural network trained on
low-level single particle features offers modest improvement in separating
signal from background, compared to BDT set-ups using physicist-engineered
high-level features. We further illustrate that while the signal acceptance of
such a deep neural network deteriorates in kinematic regions where the signal
is small, such as at high hadronic invariant mass, neural networks which
exclude kinematic features are flatter in kinematics but less inclusive in the
sampling of exclusive hadronic final states at fixed kinematics. The trade-off
between these two set-ups is somewhat Monte Carlo dependent, and we study this
issue using the multipurpose event generator Sherpa in addition to the widely
used $B$-physics tool EvtGen.
|
[
{
"created": "Wed, 19 May 2021 17:36:49 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Feb 2022 17:06:47 GMT",
"version": "v2"
}
] |
2022-02-16
|
[
[
"Biekötter",
"Anke",
""
],
[
"Kwok",
"Ka Wang",
""
],
[
"Pecjak",
"Benjamin D.",
""
]
] |
The determination of $|V_{ub}|$ in inclusive semileptonic $B \to X_u \ell \nu$ decays will be among the pivotal tasks of Belle II. In this paper we study the potential and limitations of machine learning approaches that attempt to reduce theory uncertainties by extending the experimentally accessible fiducial region of the $B\to X_u \ell\nu$ signal into regions where the $B\to X_c \ell\nu$ background is dominant. We find that a deep neural network trained on low-level single particle features offers modest improvement in separating signal from background, compared to BDT set-ups using physicist-engineered high-level features. We further illustrate that while the signal acceptance of such a deep neural network deteriorates in kinematic regions where the signal is small, such as at high hadronic invariant mass, neural networks which exclude kinematic features are flatter in kinematics but less inclusive in the sampling of exclusive hadronic final states at fixed kinematics. The trade-off between these two set-ups is somewhat Monte Carlo dependent, and we study this issue using the multipurpose event generator Sherpa in addition to the widely used $B$-physics tool EvtGen.
|
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