# Combinatorial level densities by the real-time method

## Description

Abstract Levels densities of independent-particle fermionic systems can be calculated easily by using the real-time representation of the evolution operator together with the fast Fourier transform. We describe the method and implement it with a set of Python programs. Examples are provided for the total and partial levels densities of a heavy deformed nucleus (164Dy). The partial level densities that may be calculated are the projected ones on neutron number, proton number, azimuthal angular momentum... Title of program: rt_levels.py Catalogue Id: AEUI_v1_0 Nature of problem Compute many-body level densities of finite systems of fermions described by their single-particle spectra Versions of this program held in the CPC repository in Mendeley Data AEUI_v1_0; rt_levels.py; 10.1016/j.cpc.2014.08.012 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)