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Microscopic Nuclear Level Densities from Fe to Ge by the Shell Model Monte Carlo Method

H. Nakada·Y. Alhassid
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Abstract

We calculate microscopically total and parity-projected level densities for $β$-stable even-even nuclei between Fe and Ge, using the shell model Monte Carlo methods in the complete $(pf+0g_{9/2})$-shell. A single-particle level density parameter $a$ and backshift parameter $Δ$ are extracted by fitting the calculated densities to a backshifted Bethe formula, and their systematics are studied across the region. Shell effects are observed in $Δ$ for nuclei with Z=28 or N=28 and in the behavior of $A/a$ as a function of the number of neutrons. We find a significant parity-dependence of the level densities for nuclei with $A \alt 60$, which diminishes as $A$ increases.

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H. Nakada, Y. Alhassid. 1998-09-22. Microscopic Nuclear Level Densities from Fe to Ge by the Shell Model Monte Carlo Method. https://doi.org/10.1016/s0370-2693(98)00911-3

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