Eur. Phys. J. A (2005) 25: 23-27
https://doi.org/10.1140/epja/i2005-10066-6

Original Article

Shape evolution for Sm isotopes in relativistic mean-field theory

¹ School of Physics, Peking University, 100871, Beijing, PRC
² Institute of Theoretical Physics, Chinese Academy of Sciences, 100080, Beijing, PRC
³ Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, 730000, Lanzhou, PRC
⁴ Research Center for Nuclear Physics (RCNP), Osaka University, 567-0047, Osaka, Ibaraki, Japan

^* e-mail: mengj@pku.edu.cn

Received: 11 January 2005
Accepted: 12 May 2005
Published online: 20 June 2005

Abstract

The evolution of shape from the spherical to the axially deformed shapes in the Sm isotopes is investigated microscopically in relativistic mean-field theory. The microscopic and self-consistent quadrupole deformation constrained relativistic mean-field calculations show a clear shape change for the even-even Sm isotopes with N = 82-96. The potential surfaces for ¹⁴⁸Sm, ¹⁵⁰Sm and ¹⁵²Sm are found to be relatively flat, which may be the possible critical-point nuclei. By examining the single-particle spectra and nearest-neighbor spacing distribution of the single-particle levels, one finds that the single-particle levels in ¹⁴⁸Sm , ¹⁵⁰Sm, and ¹⁵²Sm distribute more uniformly.