Shape transitions in exotic Si and S isotopes and tensor-force-driven Jahn-Teller effect
Abstract
We show how shape transitions in the neutron-rich exotic Si and S isotopes occur in terms of shell-model calculations with a newly constructed Hamiltonian based on V_MU interaction. We first compare the calculated spectroscopic-strength distributions for the proton 0d_5/2,3/2 and 1s_1/2 orbitals with results extracted from a 48Ca(e,e'p) experiment to show the importance of the tensor-force component of the Hamiltonian. Detailed calculations for the excitation energies, B(E2) and two-neutron separation energies for the Si and S isotopes show excellent agreement with experimental data. The potential energy surface exhibits rapid shape transitions along the isotopic chains towards N=28 that are different for Si and S. We explain the results in terms of an intuitive picture involving a Jahn-Teller-type effect that is sensitive to the tensor-force-driven shell evolution. The closed sub-shell nucleus 42Si is a particularly good example of how the tensor-force-driven Jahn-Teller mechanism leads to a strong oblate rather than spherical shape.
Keywords
Cite
@article{arxiv.1210.5469,
title = {Shape transitions in exotic Si and S isotopes and tensor-force-driven Jahn-Teller effect},
author = {Yutaka Utsuno and Takaharu Otsuka and B. Alex Brown and Michio Honma and Takahiro Mizusaki and Noritaka Shimizu},
journal= {arXiv preprint arXiv:1210.5469},
year = {2015}
}
Comments
6 pages, 6 figures. arXiv admin note: substantial text overlap with arXiv:1201.4077