Programme

O.13 -- Oral, NCTP-43

Date: Tuesday, 31 July 2018

Time: 11:20 - 11:40

Bubble nuclei at zero and finite temperatures

N. Quang Hung (1), L. Tan Phuc (1,2), and N. Dinh Dang (3,4)

(1) Institute of Fundamental and Applied Sciences, Duy Tan University, Ho Chi Minh city, Vietnam \\ (2) Faculty of Physics and Engineering Physics, Vietnam National University Ho Chi Minh City-University of Science, Ho Chi Minh city, Vietnam \\ (3) Quantum Hadron Physics Laboratory, RIKEN Nishina Center for Accelerator-Based Science, 2-1 Hirosawa, Wako City, 351-0198 Saitama, Japan (4) Institute for Nuclear Science and Technique, Hanoi, Vietnam

Nuclear bubble structure characterized by the depletion of the nucleon (proton/neutron) density at its center is studied within the Skyrme Hartree-Fock mean field consistently incorporating the pairing correlation, which is obtained by using the finite-temperature Bardeen-Cooper-Schrieffer theory and the exact pairing at finite temperature [1]. The numerical tests are performed for two spherical nuclei, $^{22}$O and $^{34}$Si, whose bubble structures, caused by a very low occupancy of the $2s_{1/2}$ single-particle level, were previously predicted at zero temperature. With the use of MSk3 nucleon-nucleon force, we are able to reproduce the experimentally measured occupancy of the $2s_{1/2}$ proton level as well as the binding energy, and consequently the most pronounced bubble structure in $^{34}$Si. Moreover, our approach with exact pairing predicts a pairing effect which is stronger in $^{22}$O and weaker in $^{34}$Si as compared with other approaches, which use the approximate pairing. With increasing temperature, the bubble structure is found to be depleted and completely washed out when the temperature reaches a critical value, above which the factor measuring the depletion of the nucleon density vanishes. References [1] L. Tan Phuc, N. Quang Hung, and N. Dinh Dang, Phys. Rev. C 97, 024331 (2018).

Presenter: Nguyen Quang Hung