Transverse momentum dependent parton distributions in a light-cone quark model

TL;DR

This paper investigates transverse momentum dependent parton distributions within a light-cone quark model, deriving analytic expressions and analyzing the nucleon's shape through the pretzelosity distribution.

Contribution

It provides the first analytic expressions for TMDs in a light-cone quark model considering only valence quarks, and explores the nucleon's shape via pretzelosity.

Findings

Numerical results for T-even TMDs are presented.

Pretzelosity influences the nucleon's nonspherical shape.

Analytic expressions relate TMDs to light-cone wave function amplitudes.

Abstract

The leading twist transverse momentum dependent parton distributions (TMDs) are studied in a light-cone description of the nucleon where the Fock expansion is truncated to consider only valence quarks. General analytic expressions are derived in terms of the six amplitudes needed to describe the three-quark sector of the nucleon light-cone wave function. Numerical calculations for the T-even TMDs are presented in a light-cone constituent quark model, and the role of the so-called pretzelosity is investigated to produce a nonspherical shape of the nucleon.