Eur. Phys. J. A 24, s1.143-s1.147 (2005)
DOI: 10.1140/epjad/s2005-05-025-7

Spin asymmetries for confined Dirac particles

M.W. Paris¹, V.R. Pandharipande² and I. Sick<sup>3

1</sup>  Thomas Jefferson National Accelerator Facility, MS12H2, 12000 Jefferson Ave, Newport News, VA, 23606, USA
²  Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
³  Departement für Physik und Astronomie, Universität Basel, Switzerland

(Received 27 September 2004 / Published online 08 February 2005)

Abstract

We study the Bjorken x (or equivalently Nachtmann ξ) dependence of the virtual photon spin asymmetry in polarized deep inelastic scattering of electrons from hadrons. We use an exactly solved relativistic potential model of the hadron, treating the constituents as independent massless Dirac particles confined to an infinitely massive force center. The importance of including the p-wave components of the Dirac wave function is demonstrated. Comparisons are made to the observed data on the proton by taking into account the observed flavor dependence of the valence quark distribution functions.

PACS: 13.60.Hb Photon and charged-lepton interactions with hadrons - 12.39.Ki Relativistic quark model - 12.39.Pn Potential model

© Società Italiana di Fisica, Springer-Verlag 2005