Kaon polarizability in the Nambu-Jona-Lasinio model at zero and finite temperature

D. Ebert, M. K. Volkov

Using recent data for the decays $f_0\to \gamma \gamma$, $f_0\to \pi \pi$, we determine the mixing angle of scalar mesons in a chiral quark $\sigma$-model. This value is employed to analyze of the ka…