Shape transition in some rare-earth nuclei in relativistic mean field theory
نویسندگان
چکیده
A systematic study of the temperature dependence of the shapes and pairing gaps of some isotopes in the rare-earth region is made in the relativistic Hartree-BCS theory. Thermal response to these nuclei is always found to lead to a phase transition from the superfluid to the normal phase at a temperature T∆ ∼ 0.4 − 0.8 MeV and a shape transition from prolate to spherical shapes at Tc ∼ 1.0−2.5 MeV. These shape transition temperatures are appreciably higher than the corresponding ones calculated in the non-relativistic framework with the pairing plus quadrupole interaction. Study of nuclei with continued addition of neutron pairs for a given isotope shows that with increased ground state deformation, the transition to the spherical shape is delayed in temperature. A strong linear correlation between T∆ and the ground state pairing gap ∆0 is observed; a well-marked linear correlation between Tc and the ground state quadrupole defromation β0 2 is also seen. The thermal evolution of the hexadecapole deformation is further presented in the paper. PACS numbers: 21.10.Ma, 21.60.-n, 27.70.+q E-mail:[email protected] 1
منابع مشابه
Anatomy of nuclear shape transition in the relativistic mean field theory
A detailed microscopic study of the temperature dependence of the shapes of some rare-earth nuclei is made in the relativistic mean field theory. Analyses of the thermal evolution of the single-particle orbitals and their occupancies leading to the collapse of the deformation are presented. The role of the nonlinear σ−field on the shape transition in different nuclei is also investigated; in it...
متن کاملRare-Earth Nuclei: Radii, Isotope-Shifts and Deformation Properties in the Relativistic Mean Field Theory
A systematic study of the ground-state properties of even-even rare earth nuclei has been performed in the framework of the Relativistic MeanField (RMF) theory using the parameter set NL-SH. Nuclear radii, isotope shifts and deformation properties of the heavier rare-earth nuclei have been obtained, which encompass atomic numbers ranging from Z=60 to Z=70 and include a large range of isospin. I...
متن کاملv 1 2 9 O ct 1 99 5 Rare - Earth Nuclei : Radii , Isotope - Shifts and Deformation Properties in the Relativistic Mean Field Theory
متن کامل
Nuclear shape transition at finite temperature in a relativistic mean field approach
The relativistic Hartree-BCS theory is applied to study the temperature dependence of nuclear shape and pairing gap for 166Er and 170Er. For both the nuclei, we find that as temperature increases the pairing gap vanishes leading to phase transition from superfluid to normal phase as is observed in nonrelativistic calculation. The deformation evolves from prolate shapes to spherical shapes at T ...
متن کاملNuclear deformation at finite temperature.
Deformation, a key concept in our understanding of heavy nuclei, is based on a mean-field description that breaks the rotational invariance of the nuclear many-body Hamiltonian. We present a method to analyze nuclear deformations at finite temperature in a framework that preserves rotational invariance. The auxiliary-field Monte Carlo method is used to generate a statistical ensemble and calcul...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2000