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arXiv · 2006.03868

Level density within a micro-macroscopic approach

A. G. Magner·A. I. Sanzhur·S. N. Fedotkin·A. I. Levon·S. Shlomo
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Abstract

Statistical level density $ρ(E,A)$ is derived for nucleonic system with a given energy $E$, particle number $A$ and other integrals of motion in the micro-macroscopic approximation beyond the standard saddle-point method of the Fermi gas model. This level density reaches the two limits; the well-known Fermi gas grand-canonical ensemble limit for a large entropy $S$ related to large excitation energies, and the finite micro-canonical limit for a small combinatorical entropy $S$ at low excitation energies. The inverse level density parameter $K$ as function of the particle number $A$ in the semiclassical periodic orbit theory, taking into account the extended Thomas-Fermi and Strutinsky shell corrections, is calculated and compared with experimental data.

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A. G. Magner, A. I. Sanzhur, S. N. Fedotkin, A. I. Levon, S. Shlomo. 2022-03-06. Level density within a micro-macroscopic approach. https://doi.org/10.1016/j.nuclphysa.2022.122423

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