Distribution amplitudes of heavy-light pseudo-scalar and vector mesons from Dyson-Schwinger equations framework

TL;DR

This paper uses Dyson-Schwinger equations to predict the distribution amplitudes of various heavy-light mesons, revealing flavor asymmetry and spin effects, and providing results that can be compared with future experiments.

Contribution

First Dyson-Schwinger equation predictions for heavy-light meson distribution amplitudes, extending to multiple meson types and analyzing flavor and spin effects.

Findings

Distribution amplitude skewed toward heavier quark in flavor-asymmetric systems

Heavier quarks carry more light-front momentum in vector mesons

Spin effects are subleading compared to valence-quark composition

Abstract

We report the first Dyson-Schwinger equation predictions for the leading-twist distribution amplitudes of the $B^*$, $B_s^*$, and $B_c^*$ mesons, and extend the investigation to a broader set of heavy-light pseudo-scalar/vector mesons. Numerical analysis shows that, in flavor-asymmetric systems, the distribution amplitude is skewed toward the heavier quark, with the position of the maximum $\sim M^f_E/(M^f_E+M^g_E)$, where $M_E$ is the Euclidean constituent quark mass and $f$, $g$ denote the quark flavors. Spin effects are found to be subleading compared to the influence of valence-quark composition, and lead to heavier quarks carrying more light-front momentum in vector mesons than in their pseudo-scalar counterparts. Our results can be compared with both experimental and theoretical outcomes in the future.