Deep inelastic scattering of polarized electrons by polarized 3He and the study of the neutron spin structure.

The neutron longitudinal and transverse asymmetries A n 1 and A n 2 have been extracted from deep inelas-tic scattering of polarized electrons by a polarized 3 He target at incident energies of 19.42, 22.66 and 25.51 GeV. The measurement allows for the determination of the neutron spin structure functions g n 1 (x; Q 2) and g n 2 (x; Q 2) over the range 0:03 < x < 0:6 at an average Q 2 of 2 (GeV=c) 2. The data are used for the evaluation of the Ellis-Jaae and Bjorken sum rules. The neutron spin structure function g n 1 (x; Q 2) is small and negative within the range of our measurement, yielding an integral R 0:6 0:03 g n 1 (x)dx = 0:0280:006 (stat)0:006 (syst). Assuming Regge behavior at low x, we extract n 1 = R 1 0 g n 1 (x)dx = 0:031 0:006 (stat) 0:009 (syst). Combined with previous proton integral results from SLAC experiment E143, we nd p 1 n 1 = 0:1600:015 in agreement with the Bjorken sum rule prediction p 1 n 1 = 0:176 0:008 at a Q 2 value of 3 (GeV=c) 2 evaluated using s = 0:32 0:05.