Pi-Pi scattering lengths at finite temperature

E. Quack, P. Zhuang, Y. Kalinovsky +2

The $s$-wave $\pi -\pi$ scattering lengths $a^I(T)$ at finite temperature $T$ and isospin $I=0,2$ are calculated within the SU(2) Nambu--Jona-Lasinio model. $a^2(T)$ displays a singular…