TMD densities from the Parton branching method

Abstract

We present results from a Parton branching solution of the DGLAP equation at LO, NLO and NNLO which is is capable to extract both the collinear part and the transverse momentum dependent part of the parton densities. We demonstrate that within our method the collinear part of parton densities exactly corresponds to the semi-analytical solution of the DGLAP equation up to NNLO. Moreover, we study the transverse momentum of parton densities with respect to the parton flavour, ordering condition used during the evolution and the intrinsic momentum.

Collinear and TMD parton densities from fits to precision DIS measurements in the parton branching method

“…(2) are given in [16]. The n ¼ 3 (NNLO) contributions can be read from [7,8] and are used for NNLO calculations in the PB method in [26]. The integrals appearing in the Sudakov form factors Eq.…”

“…These equations have been shown to be equivalent to DGLAP evolution equations at NLO [15,16,20,21] and NNLO [26] for α s ¼ α s ðμ 02 Þ and z M → 1.…”

Determination and application of TMD parton densities using the Parton Branching method

“…The PB method has shown to be valid for leading-order (LO), next-to-LO (NLO) and next-to-NLO (NNLO). Along this line, the agreement within a percent of the integrated TMDs obtained by this method, with the corresponding semi-analytical solution of the DGLAP [6,7,8] evolution (implemented in Qcdnum [9]) was achieved at LO, NLO and NNLO [1,2,10]. In this report the determination of parton densities at NLO obtained using the PB method is presented together with applications of the obtained TMDs to LHC processes (Drell-Yan and azimuthal correlations in dijet events).…”