Theoretical Update of Twist-3 Single-Spin Asymmetry in Semi-Inclusive DIS

Abstract

We discuss the single-spin asymmetry in semi-inclusive DIS, $e{p}^{\uparrow }\to e\pi X$, based on the twist-3 mechanism in the collinear factorization relevant for the pion production with the large transverse-momentum. This updates our previous study by including, in particular, the contributions induced by the novel partonic subprocesses, and allows us to derive the entire formula for the corresponding single-spin asymmetry associated with a complete set of the twist-3 quark-gluon correlation functions in the transversely polarized nucleon. We discuss the correspondence with the results obtained by the transverse-momentum-dependent factorization relevant for the pion production with the low transverse-momentum.

Comments: 5 pages, 2 figures. To appear in the proceedings of the XVII International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2009), Madrid, Spain, 26-30 April, 2009