The light scalar $K_{0}^{*}(700)$ meson in vacuum and a hot medium

K. Azizi, B. Barsbay, H. Sundu

Published 2019-09-02Version 1

The $K_{0}^{*}(700)$ meson appears as the lightest strange scalar meson in PDG. Although there were a lot of experimental and theoretical efforts to establish this particle and determine its properties and nature, it still needs confirmation in the experiment and its internal quark-gluon organization needs to be clarified. In this connection, we study some spectroscopic properties of this state in a hot medium as well as vacuum. In particular, we investigate its mass and coupling or decay constant in terms of the temperature of a hot medium by including the medium effects by the fermionic and gluonic parts of the energy momentum tensor as well as the temperature-dependent continuum threshold, quark, gluon and mixed condensates. We observe that the mass of $K_{0}^{*}(700)$ remains unchanged up to $T \simeq 0.6 ~ T_c$ with $ T_c $ being the critical temperature, but it starts to diminish after this point and approaches to zero near to the critical temperature referring to the melting of the meson. The coupling of $K_{0}^{*}(700)$ is also sensitive to $ T $ at higher temperatures. It starts to grow rapidly after $T \simeq 0.85 ~ T_c$. We turn off the medium effects and calculate the mass and coupling of $K_{0}^{*}(700)$ state at zero temperature. The obtained mass is in accord with the average Breit-Wigner mass value reported by PDG.