HAL : in2p3-00177434, version 1
 arXiv : 0710.1266
 Physical Review D 77 (2008) 014015
 Collisional Energy Loss of a Fast Muon in a Hot QED Plasma
 (2008)
 We calculate the collisional energy loss of a muon of high energy $E$ in a hot QED plasma beyond logarithmic accuracy, i.e., we determine the constant terms of order O(1) in $-dE/dx \propto \ln{E}+ O(1)$. Considering first the $t$-channel contribution to $-dE/dx$, we show that the terms $\sim O(1)$ are sensitive to the full kinematic region for the momentum exchange $q$ in elastic scattering, including large values $q \sim O(E)$. We thus redress a previous calculation by Braaten and Thoma, which assumed $q << E$ and could not find the correct constant (in the large $E$ limit). The relevance of 'very hard' momentum transfers then requires, for consistency, that $s$ and $u$-channel contributions from Compton scattering must be included, bringing a second modification to the Braaten-Thoma result. Most importantly, Compton scattering yields an additional large logarithm in $-dE/dx$. Our results might have implications in the QCD case of parton collisional energy loss in a quark gluon plasma.
 Thème(s) : Physique/Physique des Hautes Energies - Phénoménologie
 Mot(s)-clé(s) : QED – plasma
 Lien vers le texte intégral : http://fr.arXiv.org/abs/0710.1266
 in2p3-00177434, version 1 http://hal.in2p3.fr/in2p3-00177434 oai:hal.in2p3.fr:in2p3-00177434 Contributeur : Dominique Girod <> Soumis le : Lundi 8 Octobre 2007, 10:51:17 Dernière modification le : Vendredi 18 Janvier 2008, 15:14:00