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Demonstration of the auxiliary-field Monte Carlo approach for sd-shell nuclei

W. E. Ormand·D. J. Dean·C. W. Johnson·G. H. Lang·S. E. Koonin
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Abstract

We apply the auxiliary-field Monte Carlo approach to the nuclear shell model in the 1s-0d configuration space. The Hamiltonian was chosen to have isovector pairing and isoscalar multipole-multipole interactions, and the calculations were performed within the fixed-particle, canonical ensemble. The results demonstrate the feasibility of the method for $N\neq Z$ even-even and odd-odd N=Z nuclei. In particular, static observables for even-even Ne isotopes and Na-22 compare well with results obtained from exact diagonalization of the Hamiltonian. Response functions are presented for Ne-22 and compared with exact results, and the viability of cranked calculations for $N\neq Z$ even-even nuclei is addressed. We present methods for computing observables in the canonical ensemble using Fourier extraction, and for determining the nuclear shape.

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W. E. Ormand, D. J. Dean, C. W. Johnson, G. H. Lang, S. E. Koonin. 1993-07-14. Demonstration of the auxiliary-field Monte Carlo approach for sd-shell nuclei. https://doi.org/10.1103/physrevc.49.1422

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