Excitation modes and collective inertia in triaxial superfluid nuclei

Phenomena of shape fluctuation and shape mixing in nuclei appear in transitional regions. For these phenomena, our goal is to construct the collective Hamiltonian by the constrained Hartree-Fock-Bogoliubov (CHFB) for the collective potential and local quasiparticle random phase approximation (LQRPA) for the collective inertia with Skyrme energy density functionals. With the help of the finite amplitude method (FAM)[1] that efficiently obtains response functions with less computational cost than that of QRPA, we constructed Skyrme FAM in three-dimensional coordinate[2]. Then, we extended our 3D FAM to calculating rotational moment of inertia at triaxially-constrained HFB states[3]. In this contribution, we will present those results and discuss the phenomena of shape fluctuations in transitional nuclei.

 [1] T. Nakatsukasa, T. Inakura, and K. Yabana, Phys.Rev.C 76, 024318 (2007)

 [2] K. Washiyama and T. Nakatsukasa, Phys.Rev.C 96, 041304(R) (2017)

 [3] K. Washiyama and T. Nakatsukasa, arXiv:1803.06828