Q2 evolution of3He spin structure functions moments.

Sum rules offer the opportunity to test our understanding of the structure of a system on general grounds. In this paper we investigate the3He nucleus using the Gerasimov-Drell-Hearn and Burkhardt-Cottingham sum rules. We have previously used the polarized3He target measurements to extract the neutron spin structure, our goal here is to investigate rather the3He nucleus. We have determined for the first time theQ2 evolution ofandfor3He in the range 0.1 GeV2 =Q2 = 0.9 GeV2 with good precision.G1(Q2) displays a smooth variation from high to lowQ2. However, we do not see yet its expected turnover toward the real photon limit value. On the other hand the Burkhardt-Cottingham sum rule holds at all measuredQ2s within uncertainties due mainly to cancellations between the elastic, quasielastic and the?(1232) resonance contributions. [ABSTRACT FROM AUTHOR]