Comparison of NNLO DIS scheme splitting functions with results from exact gluon kinematics at small x.

Abstract

We consider the effect of exact gluon kinematics in the virtual photon-gluon impact factor at small x. By comparing with fixed order DIS scheme splitting and coefficient functions, we show that the exact kinematics results match the fixed order results well at each order, which suggests that they allow for an accurate NLL analysis of proton structure functions. We also present, available for the first time, x-space parameterisations of the NNLO DGLAP splitting functions in the DIS scheme, and also the longitudinal coefficients for neutral current scattering.