The transverse momentum dependent distribution functions in the bag model

TL;DR

This paper investigates leading and subleading twist transverse momentum dependent distribution functions within the bag model, deriving relations among TMDs, exploring their model dependence, and connecting pretzelosity to quark orbital angular momentum, with numerical and phenomenological insights.

Contribution

It provides a comprehensive analysis of TMDs in the bag model, including relations, model dependence, and a connection to quark orbital angular momentum, with numerical validation.

Findings

Bag model supports Gaussian transverse momentum dependence of TMDs in valence-x region.

Derived relations among different TMDs and discussed their model dependence.

Numerical results align with phenomenological expectations.

Abstract

Leading and subleading twist transverse momentum dependent parton distribution functions (TMDs) are studied in a quark model framework provided by the bag model. A complete set of relations among different TMDs is derived, and the question is discussed how model-(in)dependent such relations are. A connection of the pretzelosity distribution and quark orbital angular momentum is derived. Numerical results are presented, and applications for phenomenology discussed. In particular, it is shown that in the valence-x region the bag model supports a Gaussian Ansatz for the transverse momentum dependence of TMDs.