Shell model Monte Carlo studies of nuclei in the A∼80 mass region

Abstract

We perform shell model Monte Carlo calculations for proton-rich Kr, Sr, and Zr isotopes in the mass range A=72–84. We employ a complete 1 p0 f–0 g1 d2 s configuration space and an effective quadrupole-plus-pairing residual interaction. Our calculation reproduces the large B( E2) values observed in these nuclei. We relate these values to the gain in correlation energy obtained by moving nucleons across the N=40 subshell closure into g 9/2 orbitals.