Double parton distributions in the pion in the Nambu and Jona-Lasinio model

TL;DR

This paper investigates the non-perturbative two-parton correlations in the pion using the Nambu-Jona-Lasinio model, revealing new dynamical insights into pion structure beyond single-parton distributions.

Contribution

It provides novel calculations of double parton distribution functions in the pion within the NJL model, including different regularizations, offering predictions relevant for upcoming lattice QCD data.

Findings

Double parton distributions reveal new dynamical information about the pion.

Expressions and predictions are provided for leading-twist Dirac operators.

Results are relevant for future lattice QCD studies.

Abstract

Two-parton correlations in the pion, a non perturbative information encoded in double parton distribution functions, are investigated in the Nambu and Jona-Lasinio model. It is found that double parton distribution functions expose novel dynamical information on the structure of the pion, not accessible through one-body parton distributions, as it happens in several estimates for the proton target and in a previous evaluation for the pion, in a light-cone framework. Expressions and predictions are given for double parton distributions corresponding to leading-twist Dirac operators in the quark vertices, and to different regularization methods for the Nambu and Jona-Lasinio model. These results are particularly relevant in view of forthcoming lattice data.