Target mass corrections for spin-dependent structure functions in collinear factorization

TL;DR

This paper derives target mass corrections for spin-dependent nucleon structure functions within collinear factorization, revealing their significance at high xB and contrasting effects on polarization asymmetry A1 at low Q^2.

Contribution

It provides a new derivation of target mass corrections for g1 and A1 in collinear factorization, highlighting differences from operator product expansion results.

Findings

TMCs significantly affect g1 at large xB

TMCs largely cancel in A1

Differences between collinear and OPE corrections at low Q^2

Abstract

We derive target mass corrections (TMC) for the spin-dependent nucleon structure function g1 and polarization asymmetry A1 in collinear factorization at leading twist. The TMCs are found to be significant for g1 at large xB, even at relatively high Q^2 values, but largely cancel in A1. A comparison of TMCs obtained from collinear factorization and from the operator product expansion shows that at low Q^2 the corrections drive the proton A1 in opposite directions.