Pairing and specific heat in hot nuclei

1 Théorie
GANIL - Grand Accélérateur National d'Ions Lourds
2 Théorie
IPNO - Institut de Physique Nucléaire d'Orsay, GANIL - Grand Accélérateur National d'Ions Lourds
Abstract : The thermodynamics of pairing phase-transition in nuclei is studied in the canonical ensemble and treating the pairing correlations in a finite-temperature variation after projection BCS approach (FT-VAP). Due to the restoration of particle number conservation, the pairing gap and the specific heat calculated in the FT-VAP approach vary smoothly with the temperature, indicating a gradual transition from the superfluid to the normal phase, as expected in finite systems. We have checked that the predictions of the FT-VAP approach are very accurate when compared to the results obtained by an exact diagonalization of the pairing Hamiltonian. The influence of pairing correlations on specific heat is analysed for the isotopes $^{161,162}$Dy and $^{171,172}$Yb. It is shown that the FT-VAP approach, applied with a level density provided by mean field calculations and supplemented, at high energies, by the level density of the back-shifted Fermi gas model, can approximate reasonably well the main properties of specific heat extracted from experimental data. However, the detailed shape of the calculated specific heat is rather sensitive to the assumption made for the mean field.
Document type :
Journal articles
Domain :

http://hal.in2p3.fr/in2p3-00844821
Contributor : Michel Lion <>
Submitted on : Tuesday, July 16, 2013 - 8:53:22 AM
Last modification on : Wednesday, September 16, 2020 - 5:43:39 PM

Citation

D. Gambacurta, David Lacroix, N. Sandulescu. Pairing and specific heat in hot nuclei. Physical Review C, American Physical Society, 2013, 88, pp.034324. ⟨10.1103/PhysRevC.88.034324⟩. ⟨in2p3-00844821⟩

Record views