On higher-order flavour-singlet splitting and coefficient functions at large x
Abstract
We discuss the large-x behaviour of the splitting functions P_qg and P_gq and of flavour-singlet coefficient functions, such as the gluon contributions C_2,g and C_L,g to the structure functions F_2,L, in massless perturbative QCD. These quantities are suppressed by one or two powers of 1-x with respect to the 1/(1-x) terms which are the subject of the well-known threshold exponentiation. We show that the double-logarithmic contributions to P_qg, P_gq and C_L at order alpha_s^4 can be predicted from known third-order results and present, as a first step towards a full all-order generalization, the leading-logarithmic large-x behaviour of P_qg, P_gq and C_2,g at all orders in alpha_s.
Cite
@article{arxiv.1008.0952,
title = {On higher-order flavour-singlet splitting and coefficient functions at large x},
author = {A. Vogt and G. Soar and S. Moch and J. A. M. Vermaseren},
journal= {arXiv preprint arXiv:1008.0952},
year = {2010}
}
Comments
6 pages, LaTeX, 2 ps/eps-figures. Contribution to the proceedings of the workshops `Loops and Legs in Quantum Field Theory', April 2010, Woerlitz (Germany) and (shortened) DIS 2010 (Florence), April 2010