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Particle-Number Reprojection in the Shell Model Monte Carlo Method: Application to Nuclear Level Densities

Y. Alhassid·S. Liu·H. Nakada
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Abstract

We introduce a particle-number reprojection method in the shell model Monte Carlo that enables the calculation of observables for a series of nuclei using a Monte Carlo sampling for a single nucleus. The method is used to calculate nuclear level densities in the complete $(pf+g_{9/2})$-shell using a good-sign Hamiltonian. Level densities of odd-A and odd-odd nuclei are reliably extracted despite an additional sign problem. Both the mass and the $T_z$ dependence of the experimental level densities are well described without any adjustable parameters. The single-particle level density parameter is found to vary smoothly with mass. The odd-even staggering observed in the calculated backshift parameter follows the experimental data more closely than do empirical formulae.

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Y. Alhassid, S. Liu, H. Nakada. 1999-10-14. Particle-Number Reprojection in the Shell Model Monte Carlo Method: Application to Nuclear Level Densities. https://doi.org/10.1103/physrevlett.83.4265

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