PARTON DISTRlBUTIONS AND THEIR SYMMETRlES

Abstract

We develop the field theoretical tools necessary to understand the complicated structure of nucleonic parton distributions and wave functions. In order to parametrize these non-perturbative objects in QeD symmetries imposed by parity, time-reversal, and hermitian conjugation are used. After some general discussions about the classification of all leading -twist distribution functions a special kind of distribution function, which is odd under time reversal, is considered. This T-odd distribution function, which was recently been shown to be non zero, was recalculated and the results in the literature were confirmed.