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arXiv · 1307.0400

Nuclear Level Densities at High Excitation Energies and for Large Particle Numbers

Adriana Pálffy·Hans A. Weidenmüller
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Abstract

Starting from an independent-particle model with a finite and arbitrary set of single-particle energies, we develop an analytical approximation to the many-body level density $ρ_A(E)$ and to particle-hole densities. We use exact expressions for the low-order moments and cumulants to derive approximate expressions for the coefficients of an expansion of these densities in terms of orthogonal polynomials. The approach is asymptotically (mass number $A \gg 1$) convergent and, for large $A$, covers about 20 orders of magnitude near the maximum of $ρ_A(E)$ (i.e., about half the spectrum). Densities of accessible states are calculated using the Fermi-gas model.

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Adriana Pálffy, Hans A. Weidenmüller. 2013-09-27. Nuclear Level Densities at High Excitation Energies and for Large Particle Numbers. https://doi.org/10.1016/j.nuclphysa.2013.08.011

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