ONE-LOOP CALCULATIONS ON THE WESS-ZUMINO-WITTEN ANOMALOUS FUNCTIONAL AT FINITE-TEMPERATURE

We analyze the finite temperature (T) extension of the Wess-Zumino-Witten functional, discussed in a previous work, to one loop in chiral perturbation theory. As a phenomenological application, we calculate finite temperature corrections to the amplitude of pi0 decay into two photons. This calculation is performed in three limits : i) T/M(pi) << 1, ii) the chiral limit at finite T and iii) T/M(pi) >> 1 (M(pi) being the pion mass). The T-corrections tend to vanish in the chiral limit, where only the kaon contribution remains (although it is exponentially suppressed).