Pomeron in exclusive vector meson production

Abstract

An earlier developed model for vector meson photoproduction, based on a dipole Pomeron exchange, is extended to electroproduction. Universality of the non linear Pomeron trajectory is tested by fitting the model to ZEUS and

Ultrahigh-Energy Neutrino-Nucleon Deep-Inelastic Scattering and the Froissart Bound

“…Since these limits directly depend on the total cross section σ νN (E ν ) of UHE-neutrino deep-inelastic scattering (DIS) off nucleons (N ), it is an urgent task to provide reliable theoretical predictions for the latter in the asymptotic high-E ν regime, which lies far beyond the one explored by laboratory-based νN DIS experiments and corresponds to asymptotically low values of Bjorken's scaling variable x. This requires extrapolation over several orders of magnitude in E ν , for which various approaches exist [2][3][4][5][6][7][8]. These are based on successful descriptions of the terrestrial data within the framework of perturbative QCD and frequently impose the Froissart bound [9] on σ νN .…”

“…To be on the conservative side, we assume for the time being, as in Refs. [2][3][4][5][6][7][8], that the available experimental data on DIS allow for an extrapolation to very high (low) values of E ν (x) using an appropriate parameterization of F νN 2 . If the latter rises too steeply as x → 0, then possible new QCD phenomena, such as gluon saturation or recombination, color glass condensates, multiple pomeron exchanges, etc., are expected to enter the stage as a cure at x values below those currently probed by DIS experiments (for a review, see Ref.…”

Diffractive vector meson production

“…The dipole singularity model for virtual photoproduction of vector mesons has been proposed by Fiore et al [229,230], in this specific example the nonlinear Pomeron trajectory with the branching point singularity at the two-pion threshold in the t-channel is used. For each and every vector meson a good description of the vector meson production cross sections is found at the expense of five free parameters.…”

“…The plot taken from [173] shows the pQCD calculations for the GRV95 [293] and MRS95 [294] parameterizations of the proton gluon density based on the pre-1995 data on F 2p (x, Q 2 ) and illustrates the status of the subject at that time. The right box: the parameterization of the energy dependence of J/ψ production in the Fiore et al model of a double-pole Pomeron with intercept α IP (0) = 1 [229]. recent ZEUS data on J/Ψ electroproduction shown in Fig.…”

The calculation of the differential cross section of hadron elastic scattering by transferred four-momentum within the perturbation theory

“…Модель з полюсом другого порядку аналiтичного продовження парцiальної амплiтуди в площину комплексного моменту iмпульсу розглянуто в низцi праць, наприклад [19][20][21][22]. Полюси третього порядку проаналiзовано, наприклад, у [23,24].…”