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Level density of a Fermi gas: average growth and fluctuations

Patricio Leboeuf·Jérôme Roccia
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Abstract

We compute the level density of a two--component Fermi gas as a function of the number of particles, angular momentum and excitation energy. The result includes smooth low--energy corrections to the leading Bethe term (connected to a generalization of the partition problem and Hardy--Ramanujan formula) plus oscillatory corrections that describe shell effects. When applied to nuclear level densities, the theory provides a unified formulation valid from low--lying states up to levels entering the continuum. The comparison with experimental data from neutron resonances gives excellent results.

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Patricio Leboeuf, Jérôme Roccia. 2006-02-13. Level density of a Fermi gas: average growth and fluctuations. https://doi.org/10.1103/physrevlett.97.010401%2010.1103%2Fphysrevlett.99.169901

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