Shape transition in some rareearth nuclei in relativistic mean field theory
Abstract
A systematic study of the temperature dependence of the shapes and pairing gaps of some isotopes in the rareearth region is made in the relativistic HartreeBCS 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_{Δ}~0.40.8 MeV and a shape transition from prolate to spherical shapes at T_{c}~1.02.5 MeV. These shape transition temperatures are appreciably higher than the corresponding ones calculated in the nonrelativistic 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_{Δ} and the ground state pairing gap Δ^{0} is observed; a wellmarked linear correlation between T_{c} and the ground state quadrupole defromation β^{0}_{2} is also seen. The thermal evolution of the hexadecapole deformation is further presented in the paper.
 Publication:

Physical Review C
 Pub Date:
 February 2001
 DOI:
 10.1103/PhysRevC.63.024002
 arXiv:
 arXiv:nuclth/0012001
 Bibcode:
 2001PhRvC..63b4002A
 Keywords:

 21.10.Ma;
 21.60.n;
 27.70.+q;
 Level density;
 Nuclear structure models and methods;
 150<
 =A<
 =189;
 Nuclear Theory
 EPrint:
 14 pages in REVTEX Format and 9 figures Phys. Rev. C (in press)