Proper definition and evolution of generalized transverse momentum dependent distributions

We consider one of the most fundamental sets of hadronic matrix elements, namely the generalized transverse momentum dependent distributions (GTMDs), and argue that their existing definitions lack proper evolution properties. By exploiting the similarity of GTMDs with the much better understood tran...

Full description

Bibliographic Details
Main Authors: Miguel G. Echevarria, Ahmad Idilbi, Koichi Kanazawa, Cédric Lorcé, Andreas Metz, Barbara Pasquini, Marc Schlegel
Format: Article
Language:English
Published: Elsevier 2016-08-01
Series:Physics Letters B
Online Access:http://www.sciencedirect.com/science/article/pii/S0370269316302416
Description
Summary:We consider one of the most fundamental sets of hadronic matrix elements, namely the generalized transverse momentum dependent distributions (GTMDs), and argue that their existing definitions lack proper evolution properties. By exploiting the similarity of GTMDs with the much better understood transverse momentum distributions, we argue that the existing definitions of GTMDs have to include an additional dependence on soft gluon radiation in order to render them properly defined. With this, we manage to obtain the evolution kernel of all (un)polarized quark and gluon GTMDs, which turns out to be spin independent. As a byproduct, all large logarithms can be resummed up to next-to-next-to-leading-logarithmic accuracy with the currently known perturbative ingredients.
ISSN:0370-2693
1873-2445