SPIN STRUCTURE FUNCTIONS OF THE PROTON AND DEUTERON FROM SLAC EXPERIMENTS E155 AND E155X

摘要

Experiments E155 and E155X at SLAC were polarized deep inelastic scattering measurements of the parallel and perpendicular scattering asymmetries. We extracted the polarized structure functions g1 and g2 of the proton and deuteron. Both experiments made precision measurements through a wide range in x and Q~2. These data fall into the kinematic range between existing world data and have good consistency with them. In combination with the other world data, the results for g1 allow increased constraint on NLO QCD fits to the polarized structure functions. For g2 no significant world data existed before E155X. The E155X measurement provides information about the higher twist effects in the nucleon.