Réunion GDR 2013 Résumés

The Selfconsistent Quasiparticle RPA and Its Description of Thermal Pairing Properties in Nuclei

Nguyen Dinh Dang

1 - Heavy-Ion Nuclear Physics Laboratory, Nishina Center for Accelerator-Based Science RIKEN 2-1 Hirosawa, Wako city, 351-0198 Saitama, Japan

2 - Institute for Nuclear Science and Techniques, Vietnam Atomic Energy Commission Hanoi - Vietnam

The Selfconsistent Quasiparticle RPA (SCQRPA) is constructed [1] to study the effects of fluctuations on pairing properties in finite systems. The theory is applied to nuclei at finite temperature [2] and angular momentum [3]. Particle number projection is taken into account within the Lipkin-Nogami method. Several issues such as the smoothing of superfluid-normal phase transition, thermally assisted pairing in hot rotating nuclei, extraction of the nuclear pairing gap using an improved odd-even mass difference are discussed [4]. Finally, a novel approach of embedding the projected SCQRPA eigenvalues in the canonical ensemble (CE) is proposed (the CE-SCQRPA) [5]. Applied to a doubly-folded equidistant multilevel pairing model, the proposed CE-SCQRPA produces results in good agreement with those obtained by using the exact eigenvalues, whenever the latter are possible, and is workable also for large values of particle number (N>14), where the diagonalisation of the pairing Hamiltonian is impracticable.

References

[1] N. Quang Hung and N. Dinh Dang, 
Phys. Rev. C 76 (2007) 054302 and 77 (2008) 029905(E).

[2] N. Dinh Dang and N. Quang Hung, 
Phys. Rev. C 77 (2008) 064315.

[3] N. Quang Hung and N. Dinh Dang, 
Phys. Rev. C 78 (2008) 064315.

[4] N. Quang Hung and N. Dinh Dang, 
Phys. Rev. C 79 (2009) 054328.

[5] N. Quang Hung and N. Dinh Dang, in preparation