Gorbachenko O. Effect of vibrational states on level density and nuclear temperature

Thesis deals with the investigation of vibrational state contribution to level density and effect of vibrational states on nuclear temperature. The usage of modified saddle-point method was analyzed. This method allows to calculate the level density at low excitation energies. The new response function method was developed for description of vibrational state effect on nuclear level density. This method allows most efficiently to take into account damping of the vibrational state on level density and nuclear temperature. The effect of non-markovian processes was investigated on level density of atomic nuclei. The enhancement factors of level densities are compared, that calculated within different approaches. The calculations within response function method are in a rather good agreement with that ones within method of attenuated phonon occupation numbers. They also agree reasonably with calculations of a finite temperature extension of the interacting boson model.