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 applied to calculate nuclear level densities in the complete -shell using a good-sign Hamiltonian. Level densities of odd- and odd-odd nuclei are reliably extracted despite an additional sign problem. Both the mass and the dependence of the experimental level densities are well described without any adjustable parameters. The odd-even staggering observed in the calculated backshift parameter follows the experimental data more closely than do empirical formulas.
- Received 16 August 1999
DOI:https://doi.org/10.1103/PhysRevLett.83.4265
©1999 American Physical Society