Double parton correlations and constituent quark models: a Light Front approach to the valence sector

TL;DR

This paper calculates double parton distribution functions using a Light-Front constituent quark model, revealing significant correlations at the valence scale that persist after QCD evolution to experimental energies, impacting proton scattering analyses.

Contribution

It provides the first explicit evaluation of dPDFs within a relativistic Light-Front constituent quark model, including QCD evolution to experimental scales.

Findings

Strong correlations at the model scale remain sizable at experimental scales.

Correlations decrease at low x but are relevant for spin-dependent effects.

Valence dPDFs show significant non-perturbative correlations.

Abstract

An explicit evaluation of the double parton distribution functions (dPDFs), within a relativistic Light-Front approach to constituent quark models, is presented. dPDFs encode information on the correlations between two partons inside a target and represent the non-perturbative QCD ingredient for the description of double parton scattering in proton-proton collisions, a crucial issue in the search of new Physics at the LHC. Valence dPDFs are evaluated at the low scale of the model and the perturbative scale of the experiments is reached by means of QCD evolution. The present results show that the strong correlation effects present at the scale of the model are still sizable, in the valence region, at the experimental scale. At the low values of x presently studied at the LHC the correlations become less relevant, although they are still important for the spin-dependent contributions to unpolarized proton scattering.