Variation of Effective Mass and Level Density Parameter with Nuclear Temperature in Semi-infinite Nuclear Matter

The temperature dependence of the self-energy of a particle is studied in semi-infinite nuclear matter. Based on the finite temperature Green’s function Mat-subara formalism and applying it to the single particle-states in ²⁰⁸Pb, the calculated results show that the characteristic enhancement of the effective mass at near the Fermi energy disappears at temperature T=3 MeV, and correspondingly, as a consequence the level-density parameter should decrease in agreement with recent empirical data.