Quantum Statistical Parton Distributions and the Spin Crisis

Abstract

Quantum statistical distributions for the partons provide a fair description of deep inelastic scattering data at $Q^2=3$ and $10(GeV/c{)}^2$. The study of the polarized structure functions seems to suggest an alternative possible solution of the {\it spin crisis} based on the Pauli principle. In this scheme, in fact, the defects of the Gottfried sum rule and Ellis--Jaffe sum rule for proton, result strongly connected. This possibility finds particular evidence from the phenomenological observation that the relation $\Delta u=2\tilde{F}+u-d-1$ seems well satisfied by parton distributions.

Comments: plain LaTeX, 18 pages + 14 figures, revised version with changes in the text and in some figures, to appear in Progress of Theor. Phys. Vol. 96 (October 1996) No. 4