Analytic calculation of the fourth-order quantum-chromodynamic contribution to the nonsinglet quark longitudinal structure function

Abstract

We calculate the fourth-order quantum-chromodynamic contribution to the nonsinglet quark longitudinal structure function, obtaining a completely analytic result to this order. We also calculate the fourth-order QCD corrections to the nonsinglet longitudinal coefficient function in deepinelastic scattering. A thorough comparison with previous calculations is made.