Nuclear Level Density

One of the characteristic properties of a nucleus is the nuclear level (state) density(number of levels (states) per unit energy interval) as a function of excitation energy. A level corresponds to several degenerate states. Nuclear level density is a basic quantity of the nucleus and plays an important role in both pure and applied physics. This importance comes from the wide needs for understanding the nuclear system properties such as the description of excited nuclei, the ¿ssion dynamics and the calculation of reaction cross sections. Given the experimentally observed spectrum of a nucleus in the ground state region, the level density is simply calculated by counting the number of levels (states) in a given energy interval. For heavy nuclei, the excitation energy up to which complete information (all levels measured (energy) and identi¿ed (angular momentum)) is usually available is around 2 MeV. Further, experimental information in terms of neutron or proton resonances is available at the neutron or proton separation energy. There is no information in the intermediate energy region.