Transverse moments of TMD parton densities and ultraviolet divergences

Abstract

I review some open questions relating to the large transverse momentum divergences in transverse moments of transverse momentum dependent (TMD) parton correlation func- tions. I also explain, in an abbreviated and summarized form, recent work that shows that the resulting violations of a commonly used integral relation are not perturbatively suppressed. I argue that this implies a need for more precise definitions for the correlation functions used to describe transverse moments.

11 pages, review, version published in Modern Physics Letters A, Originally prepared for DIS2020, canceled due to the Covid-19 epidemic

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Cited by in corpus (6)

• Combining nonperturbative transverse momentum dependence with TMD evolution
• The resolution to the problem of consistent large transverse momentum in TMDs
• Basics of factorization in a scalar Yukawa field theory
• Transverse Nucleon Single-Spin Asymmetry for Single-Inclusive Hadron and Jet Production at NLO Accuracy
• Twist-2 relation and sum rule for tensor-polarized parton distribution functions of spin-1 hadrons
• Tomography of Pions and Kaons in the QCD Vacuum: Transverse Momentum Dependent Parton Distribution Functions