High energy scattering and emission in QED&QCD media
Abstract
A formalism for the evaluation of the intensity of photon and gluon bremsstrahlung in QED and QCD condensed media is presented which considers general interactions beyond the Fokker-Planck/Gaussian approximation, the angular distribution of the final particles and admits finite or structured target calculations. The Boltzmann/transport approaches of Migdal, Bell and the Baier-Dokshitzer-Mueller-Peign\'e-Schiff group, and the light-cone path integral formalisms of Zakharov and Wiedemann and Gyulassy are recovered as particular cases within the Fokker-Planck limit, which assumes Brownian motion for the intervening particles. Weinberg's soft photon theorem is shown to saturate the Landau-Pomeranchuk-Migdal supression in the soft photon/gluon regime of vanishing phases. The intensity under realistic screened interactions is larger than the existing Fokker-Planck results by a factor 3-4 and the changes can not be accounted for by a single definition of the medium transport properties through . This may also suggest that larger gluon elastic cross sections, leading to the hypothesis of strongly coupled Quark Gluon Plasma, may not be required to match the data.
Keywords
Cite
@article{arxiv.1812.06903,
title = {High energy scattering and emission in QED&QCD media},
author = {Xabier Feal},
journal= {arXiv preprint arXiv:1812.06903},
year = {2019}
}
Comments
Some part of this work may overlap with arXiv:1811.01591 and arXiv:1810.02645. Version 2: Corrected missprints in Eqs. 3.174, 3.190, 3.191 and 3.197, and updated references. Comments and corrections are welcome