Effect of gamma-strength on nuclear reaction calculations

TL;DR

This paper investigates how gamma-strength influences nuclear reaction calculations by comparing experimental gamma-ray spectra and isomeric ratios with theoretical models, highlighting the impact of nuclear excited state characteristics.

Contribution

It provides a detailed analysis of gamma-strength effects on nuclear reaction modeling, using recent experimental data and various theoretical models for photon strength and level density.

Findings

Gamma-strength significantly affects reaction calculation accuracy.

Different models for photon strength impact the predicted nuclear observables.

Experimental data helps refine theoretical nuclear reaction models.

Abstract

The results of the study of gamma-transition description in fast neutron capture and photofission are presented. Recent experimental data were used, namely, the spectrum of prompt gamma-rays in the energy range 2{\div}18 MeV from 14-MeV neutron capture in natural Ni and isomeric ratios in primary fragments of photofission of the isotopes of U, Np and Pu by bremsstrahlung with end-point energies $E_e$= 10.5, 12 and 18 MeV. The data are compared with the theoretical calculations performed within EMPIRE 3.2 and TALYS 1.6 codes. The mean value of angular momenta and their distributions were determined in the primary fragments $^{84}$Br, $^{97}$Nb, $^{90}$Rb, $^{131,133}$Te, $^{132}$Sb, $^{132,134}$I, $^{135}$Xe of photofissions. An impact of the characteristics of nuclear excited states on the calculation results is studied using different models for photon strength function and nuclear level density.