16,448 research outputs found
Low-energy diffraction; a direct-channel point of view: the background
We argue that at low-energies, typical of the resonance region, the
contribution from direct-channel exotic trajectories replaces the Pomeron
exchange, typical of high energies. A dual model realizing this idea is
suggested. While at high energies it matches the Regge pole behavior, dominated
by a Pomeron exchange, at low energies it produces a smooth, structureless
behavior of the total cross section determined by a direct-channel nonlinear
exotic trajectory, dual to the Pomeron exchange.Comment: 6 pages, 1 figure. Talk presented at the Second International
"Cetraro" Workshop & NATO Advanced Research Workshop "Diffraction 2002",
Alushta, Crimea, Ukraine, August 31 - September 6, 200
UHE neutrinos: higher twists, scales, saturation
It is shown that in the ultra-high energy neutrino interactions the higher
twist corrections brought about by the non-conservation of the top-bottom
current dramatically change the longitudinal structure function, . To the
Double Leading Log Approximation simple and numerically accurate formulas for
and are derived.Comment: 5 pages, 1 figure, Talk given at Diffraction 2010, Otranto (Lecce),
Italy, September 10-15, 201
The spectrum of massive excitations of 3d 3-state Potts model and universality
We consider the mass spectrum of the 3 3-state Potts model in the broken
phase (a) near the second order Ising critical point in the temperature -
magnetic field plane and (b) near the weakly first order transition point at
zero magnetic field. In the case (a), we compare the mass spectrum with the
prediction from universality of mass ratios in the 3 Ising class; in the
case (b), we determine a mass ratio to be compared with the corresponding one
in the spectrum of screening masses of the (3+1) SU(3) pure gauge theory at
finite temperature in the deconfined phase near the transition. The agreement
in the comparison in the case (a) would represent a non-trivial test of
validity of the conjecture of spectrum universality. A positive answer to the
comparison in the case (b) would suggest the possibility to extend this
conjecture to weakly first order phase transitions.Comment: 20 pages, 12 figures; uses axodraw.st
Current non-conservation effects in DIS diffraction
In the neutrino DIS diffraction the charged current non-conservation gives
rise to sizable corrections to the longitudinal structure function, .
These corrections is a higher twist effect enhanced at small- by the rapidly
growing gluon density. The phenomenon manifests itself in abundant production
of charm and strangeness by longitudinally polarized W bosons of moderate
virtualities Q^2\lsim m_c^2.Comment: Prepared for the Int. Workshop on Diffraction in High-Energy Physics,
Diffraction 2008, La Londe-les-Maures, France, Sept. 9-14, 200
Exclusive diffractive resonance production in proton-proton collisions at high energies
A model for exclusive diffractive resonance production in proton-proton
collisions at high energies is presented. This model is able to predict double
differential distributions with respect to the mass and the transverse momentum
of the produced resonance in the mass region 5 GeV. The model is
based on convoluting the Pomeron distribution in the proton with the
Pomeron-Pomeron-meson total cross section. The Pomeron-Pomeron-meson cross
section is saturated by direct-channel contributions from the Pomeron as well
as from two different trajectories, accompanied by the isolated f
resonance dominating the GeV region. A slowly varying
background is taken into account.Comment: 11 pages, 14 figures. arXiv admin note: text overlap with
arXiv:1512.0497
Resonance production in Pomeron-Pomeron collisions at the LHC
A model for Pomeron-Pomeron total cross section in the resonance region
5 GeV is presented. This model is based on Regge poles from
the Pomeron and two different trajectories, and includes the isolated
f resonance in the region GeV. A slowly
varying background is included. The presented Pomeron-Pomeron cross section is
not directly measurable, but is an essential ingredient for calculating
exclusive resonance production at the LHC.Comment: Proceedings XXIV Int. Workshop on Deep-Inelastic Scattering and
Related Subjects (DIS16), DESY, 11-15 April 2016, 5 pages, 3 figure
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