Contribution of the twist-3 fragmentation function to single transverse-spin asymmetry in SIDIS

Abstract

We study the contribution of the twist-3 fragmentation function to the single transverse-spin asymmetry in SIDIS within the framework of the collinear factorization. Using the Ward-Takahashi identity in QCD, we establish the collinear twist-3 formalism in the Feynman gauge to calculate its non-pole contribution to the asymmetry.

Comments: 5 pages, 2 figures, to appear in the proceedings of the XXI International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS2013), 22-26 April 2013, Marseilles, France