PARTICLE-HOLE STATE DENSITIES WITH NONEQUIDISTANT SINGLE-PARTICLE LEVELS

The correct use of energy-dependent single-particle level (s.p.l.) den sities within particle-hole state densities based on the equidistant s pacing model (ESM) is analyzed. First, an analytical expression is obt ained following the convolution of energy-dependent excited-particle a nd hole densities. Next, a comparison is made with results of the ESM formula using average s.p.l. densities for the excited particles and h oles, respectively. The Fermi-gas model (FGM) s.p.l. densities calcula ted at the corresponding average excitation energies are used in both cases. The analysis concerns also the density of particle-hole bound s tates. The pairing correlations are taken into account while the compa rison of various effects includes the exact correction for the Pauli e xclusion principle. Quantum-mechanical s.p.l. densities and the contin uum effect can also match a corresponding FGM formula, suitable for us e within the average energy-dependent partial state density in multist ep reaction models.