Properties of the $D_{s0}^{\ast }(2317{)}^{\pm }$ in hot and dense nuclear matter

Abstract

We investigate the properties of the $D_{s0}^{\ast }(2317{)}^{\pm }$ in hot and dense nuclear matter using a coupled-channel molecular model built on next-to-leading-order heavy meson chiral perturbation theory. In-medium modifications to the $D_{s0}^{\ast }(2317{)}^{+}$ stem from changes to the $DK$ channel within the coupled $DK$-$D_s\eta$ system. As nuclear density increases, the $D_{s0}^{\ast }(2317{)}^{+}$ quasiparticle peak shifts toward lower energies and broadens, tracking the behavior of the $D$-meson spectral function. As for temperature effects, those are milder, with the thermal smearing of the Fermi surface and the melting of ${\Sigma }_c{N}^{-1}$ excitations in the $D$-meson spectral function shifting the $D_{s0}^{\ast }(2317{)}^{+}$ peak back toward its free-space mass while narrowing it. Conversely, the behavior of the $D_{s0}^{\ast }(2317{)}^{-}$ is governed by the $\bar{D}\bar{K}$ channel and its medium behavior is driven by the $\bar{K}$ spectral function. With increasing temperature, the $D_{s0}^{\ast }(2317{)}^{-}$ also approaches its free-space mass, but its width broadens before saturating at high temperatures. Incorporating explicit medium dependencies into the interaction kernel, driven by density and/or temperature variations in the pion decay constant, further shifts the $D_{s0}^{\ast }(2317{)}^{+}$ mass lower and narrows its width with temperature. As for $D_{s0}^{\ast }(2317{)}^{-}$, its mass also drops with temperature but its width increases. These contrasting medium behaviors offer a promising pathway to constrain the internal structure of these exotic states.

Comments: 16 pages, 10 figures