A first determination of the unpolarized quark TMDs from a global analysis

Abstract

Transverse momentum dependent distribution and fragmentation functions of unpolarized quarks inside unpolarized protons are extracted, for the first time, through a simultaneous analysis of semi-inclusive deep-inelastic scattering, Drell-Yan and $Z$ boson hadroproduction processes. This study is performed at leading order in perturbative QCD, with energy scale evolution at the next-to-leading logarithmic accuracy. Moreover, some specific choices are made to deal with low scale evolution around 1 GeV$^2$. Since only data in the low transverse momentum region are considered, no matching to fixed-order calculations at high transverse momentum is needed.

10 pages, 6 figures, 1 table; to appear in the Proceedings of the QCD Evolution 2017 Workshop, Newport News, Virginia (USA), 22 - 26 May 2017