Isospin mixing at finite temperature in 80Zr

Abstract

The degree of isospin mixing in the hot compound nucleus 80Zr has been extracted by statistical-model analysis of the γ-decay spectrum emitted in fusion reactions 40Ca+40Ca at Ebeam = 200 MeV and 37Cl+44Ca at Ebeam = 153 MeV. In the case of 40Ca+40Ca reaction an hindrance of first-step γ-decay is expected because in self-conjugate nuclei the E1 selection rules forbid the decay between states with isospin I=0. The results obtained at finite temperature (T ~ 2 MeV) have been used to extrapolate the degree of mixing at zero temperature