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Particle-hole state densities with non-equidistant single-particle levels

A. Harangozo·I. Stetcu·M. Avrigeanu·V. Avrigeanu
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Abstract

The correct use of energy-dependent single-particle level (s.p.l.) densities within particle-hole state densities based on the equidistant spacing model (ESM) is analysed. First, an analytical expression is obtained following the convolution of energy-dependent excited-particle and hole densities. Next, a comparison is made with results of the ESM formula using average s.p.l. densities for the excited particles and holes, respectively. The Fermi-gas model (FGM) s.p.l. densities calculated at the corresponding average excitation energies are used in both cases. The analysis concerns also the density of particle-hole bound states. The pairing correlations are taken into account while the comparison of various effects includes the exact correction for the Pauli exclusion principle. Quantum-mechanical s.p.l. densities and the continuum effect can also match a corresponding FGM formula, suitable for use within the average energy-dependent partial state density in multistep reaction models.

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A. Harangozo, I. Stetcu, M. Avrigeanu, V. Avrigeanu. 1998-04-29. Particle-hole state densities with non-equidistant single-particle levels. https://doi.org/10.1103/physrevc.58.295

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