Parton physics of the large-$N_c$ mesons

TL;DR

This paper explores the internal structure of large-$N_c$ mesons, especially pions, using lattice Monte Carlo methods, revealing similarities with $N_c=3$ and potential differences due to QCD evolution.

Contribution

First computation of the collinear quark-structure of large-$N_c$ pions using lattice Monte Carlo and continuum reduction techniques.

Findings

Large-$N_c$ and $N_c=3$ pion structures are similar.

Differences may stem from perturbative QCD evolution effects.

Method demonstrates effective study of meson internal structure at large-$N_c$.

Abstract

We initiate the studies on the structural physics of the tower of stable large-$N_c$ mesons through a first computation of the collinear quark-structure of a large-$N_c$ pion using lattice Monte-Carlo methods. We adapt the large-$N_c$ continuum reduction for the determination of meson correlation functions involving the spatially-extended quasi-PDF operators as a perfect strategy to concentrate only on the short perturbative length scales. We find the internal structures of pion in the large-$N_c$ and $N_c=3$ theories to be quite similar. Interestingly, we find hints that even the observed differences could arise to a large extent via the different perturbative QCD evolution in the two theories from similar initial conditions at low factorization scales.