JEFFERSON LAB 12 GEV SPIN PROGRAM

摘要

Spin structure functions provide basic information about the spin of the quark distributions inside the nucleon. Experimental understanding of the nucleon spin in the kinematic region where the three basic ("valence") quarks dominate the nucleon wave function is still rather poor. Jefferson lab, with its high quality, high polarization continuous electron beam and state of the art polarized nucleon targets in each of its three experimental halls is ideally suited for spin structure measurements in the valence region. An experimental program is underway at Jefferson Lab to measure the spin structure of the nucleon in the valence region with unprecedented precision. The planed upgrade of Jefferson lab CEBAF accelerator to 12 GeV will significantly increase the accessible kinematic range and the precision of these measurements.