70 09 v 1 1 0 Ju l 2 00 0 Level density and thermal properties in rare earth nuclei
نویسندگان
چکیده
A convergent method to extract the nuclear level density and the γ-ray strength function from primary γ-ray spectra has been established. Thermodynamical quantities have been obtained within the microcanon-ical and canonical ensemble theory. Structures in the caloric curve and in the heat capacity curve are interpreted as fingerprints of breaking of Cooper pairs and quenching of pairing correlations. The strength function can be described using models and common parameterizations for the E1, M1 and pygmy resonance strength. However, a significant decrease of the pygmy resonance strength at finite temperatures has been observed.
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