Precise Evaluation of Neutron Asymmetry by Thermodynamical Bag Model

Abstract

Neutron spin asymmetry  and the polarized structure functions  is precisely evaluated in the kinematic region 0.1< x < 0.9 and  by Thermodynamical Bag Model (TBM). The results for  and  at x=0.33 are consistent with improved precision. The evaluated values of neutron asymmetry are consistent with HERMES data showing a zero crossing around x=0.47, and the value at x=0.60 is significantly positive. The result agrees with constituent quark model predictions at high x, but disagrees with that from leading-order perturbative QCD (pQCD) assuming helicity conservation.