arXiv subjects

Hamid Kharraziha

Publications and source records attributed to Hamid Kharraziha.

3 recordsLinked to original sources

arXiv2000

A perturbative treatment of double gluon exchange in gamma*-proton DIS

A new model for the exchange of two gluons between the virtual photon and the proton, in non-diffractive deeply inelastic electron-proton scattering, is developed and studied. This model relies on a perturbative calculation, previously applied to diffraction, and a general result from Regge theory. As a first application of the model, we study corrections to the momentum transfer to the quark-anti-quark pair, at the photon-vertex. We find a significant enhancement of the cross-section at ~Q^2 momentum transfers, and large negative corrections for small momentum transfers. The implication of this result for jet-distributions measured at HERA, is discussed.

hep-ph↗

arXiv2000

The Metropolis algorithm for on-shell four-momentum phase space

We present several implementations of the Metropolis method, an adaptive Monte Carlo algorithm, which allow for the calculation of multi-dimensional integrals over arbitrary on-shell four-momentum phase space. The Metropolis technique reveals itself very suitable for the treatment of high energy processes in particle physics, particularly when the number of final state objects and of kinematic constraints on the latter gets larger. We compare the performances of the Metropolis algorithm with those of other programs widely used in numerical simulations.

hep-ph↗

arXiv1996

Colour: A Computer Program for QCD Colour Factor Calculations

A computer program for evaluating colour factors of QCD Feynman diagrams is presented, and illustrative examples on how to use the program to calculate non trivial colour factors are given. The program and the discussion in this paper is based on a diagrammatic approach to colour factors.

hep-ph↗