Couplings between the $\rho$ and $D$- and $D^\ast$-mesons

TL;DR

This paper calculates the couplings between the rho meson and D/D* mesons using a QCD-constrained framework, revealing significant differences among the couplings that challenge simplified models of meson interactions.

Contribution

It provides a consistent, QCD-based calculation of rho-D and rho-D* meson couplings, highlighting their variability and implications for meson-exchange models.

Findings

Couplings differ significantly in strength and range.

No single coupling parametrization is adequate for D-meson interactions.

Results impact phenomenological models of meson-nucleon scattering.

Abstract

We compute couplings between the $\rho$-meson and $D$- and $D^\ast$-mesons - $D^{(\ast)}\rho D^{(\ast)}$ - that are relevant to phenomenological meson-exchange models used to analyse nucleon-$D$-meson scattering and explore the possibility of exotic charmed nuclei. Our framework is built from elements constrained by Dyson-Schwinger equation studies in QCD, and therefore expresses a consistent, simultaneous description of light- and heavy-quarks and the states they constitute, We find that all interactions, including the three independent $D^{\ast} \rho \,D^{\ast}$ couplings, differ markedly amongst themselves in strength and also in range, as measured by their evolution with $\rho$-meson virtuality. As a consequence, it appears that no single coupling strength or parametrization can realistically be employed in the study of interactions between $D^{(\ast)}$-mesons and matter.