Two-loop evolution kernels for colour dependent double parton distributions

Abstract

A key ingredient in the description of double parton distributions is their scale dependence. If the colour of each individual parton is summed over, the distributions evolve with the same DGLAP kernels as ordinary parton distributions. This is no longer true if the two partons are colour correlated. We compute the relevant kernels for this case at next-to-leading order in the strong coupling, for unpolarised or longitudinally polarised partons and for transversely polarised quarks.

Comments: 41 pages, 2 figures. v2: corrections (highest order of poles, polarised valence kernels), added discussion of kinematic limits. v3: added clarifications, fixed typos