On the Anomalous Dimension of the Transversity Distribution $h_1(x,Q^2)$

Abstract

We calculate the leading order anomalous dimension of the transversity structure function directly using three different methods, the local light-cone expansion in the forward case, the non-forward case, and the short-distance expansion of the forward Compton amplitude. Our results agree with the original calculation by Artru and Mekhfi [Z. Phys. {\bf 45} (1990) 669], which has been doubted recently. We also comment on the next-to-leading order anomalous dimension.

Comments: 9 pages LATEX, 2 style files, more references added, to appear in Eur. Phys J. C