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

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 1p0f–0g1d2s 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 g9/2 orbitals.