The positivity bound for the transverse asymmetry A2 may be improved by making use of the fact, that the state of a photon and a nucleon with total spin 3/2, does not participate to the interference. The bound is therefore useful in the case of a longitudinal asymmetry small (say, at low x) or negative (like in the neuteron case).
@article{arxiv.hep-ph/9906455,
title = {Improved positivity bound for Deep Inelastic Scattering on transversely polarized nucleon},
author = {J. Soffer and O. V. Teryaev},
journal= {arXiv preprint arXiv:hep-ph/9906455},
year = {2007}
}
Comments
LaTeX, 4 pages; CPT--99/P.3845; Talk at Workshop Polarized Protons at High Eergies (DESY-Hamburg, May 17-20, 1999)