Effect of in-medium spectral density of $D$ and $D^*$ mesons on the $J/\psi$ dissociation in hadronic matter

TL;DR

This paper investigates how the in-medium spectral density modifications of D and D* mesons affect the dissociation of J/ψ in hot hadronic matter, revealing increased decay channels and dissociation widths.

Contribution

It provides a detailed calculation of the in-medium spectral functions of D and D* mesons using thermal field theory and chiral perturbation theory, highlighting their impact on J/ψ dissociation.

Findings

In-medium spectral density of D and D* mesons is significantly modified.

New subthreshold decay channels for J/ψ are opened in hadronic matter.

Dissociation width of J/ψ increases due to these medium effects.

Abstract

The one-loop self-energy of the $D$ and $D^*$ mesons in a hot hadronic medium is evaluated using the real time formalism of thermal field theory. The interaction of the heavy open-charm mesons with the thermalized constituents $(\pi,K,\eta)$ of the hadronic matter is treated in the covariant formalism of heavy meson chiral perturbation theory. The imaginary parts are extracted from the discontinuities of the self-energy function across the unitary and the Landau cuts. The non-zero contribution from the latter to the spectral density of $D$ and $D^*$ mesons opens a number of subthreshold decay channels of the $J/\psi$ leading to a significant increase in the dissociation width in hadronic matter.