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Uri Maor

Publications and source records attributed to Uri Maor.

9 recordsLinked to original sources

Unitarity Saturation In P-P Scattering

The properties of soft p-p scattering amplitudes at the TeV-scale are studied so as to identify the impact of s and t channel unitarity screenings on their behavior at exceedingly high energies and determine the rate at which they approach the bounds implied by unitarity saturation. I shall examine the relevant high energy soft cross section features, as well as, the corresponding behavior of the coupled phenomenological models aiming to reproduce this data.\\ My conclusion is that p-p black body saturation is not attained up to 100 TeV. More over, I do not expect that saturation will be attained at energies that can be investigated experimentally.

hep-ph

Inclusive production in a QCD and N=4 SYM motivated model for soft interactions

The results presented in this paper differ from our previous unsuccessful attempt to predict the rapidity distribution at $W = 7 \,TeV$. The original version of our model (GLMM) only summed a particular class of Pomeron diagrams (enhanced diagrams). We believe that this was the reason for our failure to describe the $7 \,TeV$ inclusive LHC data. We have developed a new approach (GLM) that also includes the summation of the semi-enhanced diagrams.This contribution is essential for a successful description of the inclusive distributions, which is presented here.

hep-ph

Soft Scattering Re - Visited

An updated formulation of soft diffraction, compatible with $s$ and $t$ channel unitarity, is presented. Its consequent general soft scattering features at high energies are explored. The critical interplay between theory and data analysis and its consequent implications with regards to the theoretical foundations of soft scattering theory are discussed.

hep-ph

pQCD at the Kinematical Boundary of its Applicability

I examines the applicability and possible need for a re-formulation of pQCD, as we know it, in the DIS limit of small $Q^2$ and $x$. Gluon saturation, implied by s-channel unitarity, and its possible experimental signatures are critically assessed.

hep-ph

A manifestation of a gluon saturation in e-A DIS

This is a short presentation of our talks given at eRHIC Workshop at the BNL. We give here a status report of our attempts to understand how gluon saturation will manifest itself in deep inelastic scattering with nuclei. This summary reflects our current understanding and shows directions of our research rather then a final answer to the question. Nevertheless, we are able to share with our reader our tentative answer to the question:``Why do we need to measure DIS with nuclei and why these data will be complementary to the information obtained from proton DIS".

hep-ph

An Investigation of the Hard Contribution to phi Photoproduction

We investigate the possibility that the process of phi photoproduction may have a significant hard perturbative QCD component. This suggestion is based on a study of the energy dependence of the forward phi photoproduction cross section followed by a calculation where we show that a coherent sum of the pQCD and conventional soft Pomeron contributions provides an excellent reproduction of the experimental data. Our results suggest that the transition from the predominantly soft photoproduction of light rho and omega vector mesons to the predominantly hard photoproduction of heavy J/psi and upsilon is smooth and gradual, similar to the transition observed in deep inelastic scattering studies of the proton structure function in the small x limit. Our predictions for higher HERA energies are presented.

hep-ph

Diffractive Leptoproduction of Small Masses in QCD

In this paper we consider the process of diffraction dissociation in deep inelastic scattering producing a small mass. This process is analyzed by the calculation of $\bar q\, q$ and $\bar q\, q\, G$ production. We show that the small distance contributions ($r_{\perp}\,\propto\,1/Q$) to the longitudinal polarised virtual photon dominate the diffractive channels. Formulae for the cross section using the gluon density are written within the framework of perturbative QCD. We show that the production of small masses by a transverse polarised photon is concentrated at moderate values of $r_{\perp} \,\sim\,1 GeV^{-1}$, where the pQCD approach is valid. It is shown that only $\bar q\, q$ pair production contributes to diffraction dissociation with $\b\,>\,$ 0.4 and the possibility to extract the values of the gluon density from the measurements in this kinematic region is discussed. Shadowing corrections are assessed for both longitudinal and transverse polarised photons and estimates of the different damping factors are given. The relation between diffractive production and the corrections to $F_2$ is alluded to. The evolution of the diffractive structure function is studied and a solution to the difractive evolution equations is proposed.

hep-ph