Speaker
Description
Collinear double parton distributions (DPDFs) possess a non-trivial color structure that can be classified by a projection onto irreducible representations. The DGLAP evolution equations then depend on the color representation of the respective DPDF. In the color singlet case, the DGLAP splitting kernels are identical to the ones for ordinary single parton distributions. For the color non-singlet kernels, this is not the case. At leading order in pertubation theory, they can be deduced with little effort from the color singlet ones. At next-to-leading order, the procedure becomes more involved and the kernels were unknown until now.
In this talk, I will present for the first time the full splitting kernels for unpolarized, longitudinal and quark transversity DPDFs at NLO. They were obtained using two different and independent methods. The first one is based on graph-by-graph results for PDF splitting kernels, the second one utilizes the matching formula for transverse momentum dependent matrix elements. As a by-product, the NLO anomalous dimension for rapidity evolution of DPDFs in the gluon decuplet and 27-multiplet was also obtained for the first time.
