Heavy flavor-asymmetric pseudoscalar mesons on the light front

TL;DR

This paper derives light front wave functions for heavy flavor-asymmetric mesons like D, B, and Bc using Dyson-Schwinger equations, revealing how quark mass asymmetry influences their internal structure and distributions.

Contribution

It introduces a method to extract light front wave functions from Bethe-Salpeter equations for heavy-light mesons, highlighting the role of quark mass asymmetry in their internal distributions.

Findings

Heavier quarks carry most of the longitudinal momentum.

Lighter quarks significantly influence transverse spatial and momentum distributions.

Distributions exhibit duality between light meson and heavy quarkonium characteristics.

Abstract

We extract the leading Fock-state light front wave functions (LF-LFWFs) of heavy flavor-asymmetric pseudoscalar mesons $D$, $B$ and $B_c$ from their Bethe-Salpeter wave functions based on Dyson-Schwinger equations approach, and study their leading twist parton distribution amplitudes, generalized parton distribution functions and transverse momentum dependent parton distributions. The spatial distributions of the quark and antiquark on the transverse plane are given, along with their charge and energy distributions on the light front. We find that in the considered mesons, the heavier quarks carry most longitudinal momentum fraction and yield narrow $x$-distributions, while the lighter quarks play an active role in shaping the transverse distributions within both spatial and momentum space, exhibiting a duality embodying characteristics from both light mesons and heavy quarkonium.