Measurement of the Deep-Inelastic Spin-Dependent Structure Functions of the Proton and Neutron at HERA.

摘要

It is possible to measure the deep-inelastic spin-dependent structure functions g sub 1 /sup p/(x) and g sub 1 /sup n/(x) for the proton and neutron using internal polarized hydrogen, deuterium, and sup 3 He targets of polarization 50% and thickness 10 sup 14 to 10 sup 15 cm sup -2 and the 60 mA longitudinally polarized 30 GeV electron beam in the HERA electron storage ring. The measurement of the deep-inelastic spin-structure of both isospin states of the nucleon at the same kinematics and using the same apparatus allows the Bjorken sum rule to be experimentally checked. In addition, it uniquely constrains the spin distribution of the u and d quarks as a function of x in any model of the nucleon. Possible target and detector configurations are described and an estimate of the accuracy of such a measurement is presented. (ERA citation 13:038533)