Precision Measurement of the Proton and Deuteron Spin Structure Functions g{sub 2} and Asymmetry A{sub 2} [report]

Stephen Rock
2002 unpublished
We have measured the spin structure functions g p 2 and g d 2 and the virtual photon asymmetries A p 2 and A d 2 over the kinematic range 0.02 ≤ x ≤ 0.8 and 0.7 ≤ Q 2 ≤ 20 GeV 2 by scattering 29.1 and 32.3 GeV longitudinally polarized electrons from transversely polarized NH3 and 6 LiD targets. Our measured g2 approximately follows the twist-2 Wandzura-Wilczek calculation. The twist-3 reduced matrix elements d p 2 and d n 2 are less than two standard deviations from zero. The data are
more » ... nt with the Burkhardt-Cottingham sum rule if there is no pathological behavior as x → 0. The Efremov-Leader-Teryaev integral is consistent with zero within our measured kinematic range. The absolute value of A2 is significantly smaller than the A2 < R(1 + A1)/2 limit.
doi:10.2172/799029 fatcat:2xrhpbfzqfdedl2pjqqhd3ec5y