Two-loop QED corrections to the Altarelli-Parisi splitting functions

Abstract

We compute the two-loop QED corrections to the Altarelli-Parisi (AP) splitting functions by using a deconstructive algorithmic Abelianization of the well-known NLO QCD corrections. We present explicit results for the full set of splitting kernels in a basis that includes the leptonic distribution functions that, starting from this order in the QED coupling, couple to the partonic densities. Finally, we perform a phenomenological analysis of the impact of these corrections in the splitting functions.

Comments: 17 pages, 5 figures. Typos corrected, 1 figure added. Final version published in JHEP. Comment added about Eq. (51)