The $D_{s0}(2590{)}^{+}$ as the dressed $c\bar{s}(2^1{S}_0)$ meson in a coupled-channels calculation

Abstract

The recent discovery of the $D_{s0}(2590{)}^{+}$ meson by the LHCb Collaboration has stimulated the analysis of meson-meson channels effects in the two-body quark-antiquark meson spectrum. This resonance, assigned to the radial excitation of the pseudoscalar $D_s^{+}$ meson, has a mass much lower than the predictions of naive quark models, which could indicate a non-negligible $D^{(\ast )}{K}^{(\ast )}$ coupling which reduces its mass. Based on the importance of nearby meson-meson thresholds in the dynamics of P-wave $D_s$ mesons such as the $D_{s0}^{\ast }(2317{)}^{+}$ and $D_{s1}(2460{)}^{+}$, in this work we perform a coupled-channels calculation including the $D^{(\ast )}{K}^{(\ast )}$, $D_s^{(\ast )}\omega$ and $D_s^{\ast }\eta$ channels, and study the impact of incorporating those channels in the mass of the bare $c\bar{s}$. The coupling between two and four-quark sectors is done by means of the ${}^3{P}_0$ mechanism, with all the parameters constrained from previous studies of the heavy meson spectroscopy. The masses, widths and production line shapes of the resulting state are analyzed.

Comments: 7 pages, 3 figures, 3 tables