Entropy In Hot Nuclei.

Authors :: Siem, S.
Agvaanluvsan, U.
Algin, E.
Belgya, T.
Bernstein, L. A.
Chankova, R.
Guttormsen, M.
Ingebretsen, F.
Lönnroth, T.
Messelt, S.
Mitchell, G. E.
Rekstad, J.
Schiller, A.
Sunde, A. C.
Syed, N. U. H.
Voinov, A.
Ødegård, S.
Source :: AIP Conference Proceedings; 2005, Vol. 764 Issue 1, p315-320, 6p
Publication Year :: 2005
Abstract: The level density and the γ-strength function have been extracted experimentally. From the level densities thermodynamical quantities such as temperature and heat capacity can be found. Structures in the micro-canonical temperature are interpreted as the onset of new degrees of freedom by the breaking of Cooper pairs. The S-shape in the heat capacity curves, found within the canonical ensemble, indicates the pairing-phase transition, and a critical temperature for the quenching of pair correlations is found. The pygmy resonance at 3.3(1) MeV in 172Yb has now been established with a strength of B(M1)=6.5(15)μ<subscript>N</subscript><superscript>2</superscript> and M1 multipolarity, the so-called scissors mode. In addition, a strong unexpected enhancement of the radiative strength function (RSF) has been found at low γ-ray energy in medium light Fe nuclei and also in the heavier Mo nuclei. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]