On problems of experimental determination of reliable values of nucleus parameters at low excitation energy - Ni-60 as an example

TL;DR

This paper reanalyzes experimental data on Ni-60 to accurately determine level density and gamma-ray strength functions, comparing models and identifying error regions in traditional methods, providing new insights into primary gamma-transitions.

Contribution

It introduces a methodologically correct approach to determine radiation strength functions of primary gamma-transitions over a wide energy range.

Findings

Precise approximation of level density and strength functions by models.

Identification of error regions in traditional cross-section calculations.

First-time methodologically correct data on primary gamma-transitions.

Abstract

The reanalysis of the published experimental data from reaction Co-59(p,2gamma)Ni-60 was performed. The region of the most probable values of level density and radiative strength functions of cascade gamma-transitions was determined. The obtained data were rather precisely approximated by the V.M. Strutinsky model and semi-phenomenological model - for strength functions. The region of appearance and magnitude of maximal errors of the calculated cross-section of nucleon emission in evaporation spectra in traditional methods of their analysis were determined as well. There was for the first time obtained methodically correct information on the radiation strength function of primary gamma-transitions in diapason of neutron binding energy with averaging over large set of initial levels.