- th / 9 70 80 39 v 1 2 1 A ug 1 99 7 Shell Model Monte Carlo studies of neutron - rich nuclei in the 1 s - 0 d - 1 p - 0 f shells
نویسنده
چکیده
We demonstrate the feasibility of realistic Shell Model Monte Carlo (SMMC) calculations spanning multiple major shells, paying particular attention to the center-of-mass motion. We then use this method to study a series of unstable neutron-rich nuclei with active nucleons in both the sd and pf major oscillator shells. In particular, we study nuclei around the two presumed shell closures at N = 20, 28 and show that SMMC methods can reproduce the measured mass excesses, B(E2)’s, and other observables when a suitable nuclear interaction is employed. Our calculations confirm the previously discovered disappearance of the shell gaps for these extremely neutron-rich nuclei. We close with speculations about future applications of multi-shell SMMC calculations. PACS: 21.60Cs, 21.60Ka, 27.40+z, 21.10Dr, 21.10Ky Typeset using REVTEX
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