Thermal and electromagnetic properties of Er-166 and Er-167 - art. no. 044309

The primary gamma -ray spectra of Er-166 and Er-167 are deduced from the (H e-3, alpha gamma) reaction and the (He-3,He-3' gamma) reaction, respectivel y, enabling a simultaneous extraction of the level density and the gamma -r ay-strength function. Entropy, temperature, and heat capacity are deduced f rom the level density within the microcanonical and canonical ensembles, di splaying signals of a phaselike transition from the pair-correlated ground state to an uncorrelated state at T(c)similar to0.5 MeV. The gamma -ray-str ength function displays a bump around E(gamma)similar to3 MeV, interpreted as the pygmy resonance.