Fast-neutron induced pre-equilibrium reactions on 55Mn and 63,65Cu at energies up to 40 MeV

TL;DR

This study measures neutron-induced reaction cross sections on manganese and copper isotopes up to 40 MeV and compares them with model calculations, highlighting the energy ranges where models are most sensitive and accurate.

Contribution

It provides new precise excitation function data for Mn and Cu isotopes and evaluates model predictions across a broad energy spectrum up to 50 MeV.

Findings

Model calculations align well with experimental data between 20-40 MeV.

Data sensitivity varies with energy, affecting model parameter accuracy.

Additional measurements are needed below 13.5 MeV and above 40 MeV.

Abstract

Excitation functions were measured for the $^{55}$Mn(n,2n)$^{54}$Mn, $^{55}$Mn(n,$\alpha$)$^{52}$V, $^{63}$Cu(n,$\alpha$)$^{60}$Co, $^{65}$Cu(n,2n)$^{64}$Cu, and $^{65}$Cu(n,p)$^{65}$Ni reactions from 13.47 to 14.83 MeV. The experimental cross sections are compared with the results of calculations including all activation channels for the stable isotopes of Mn and Cu, for neutron incident energies up to 50 MeV. Within the energy range up to 20 MeV the model calculations are most sensitive to the parameters related to nuclei in the early stages of the reaction, while the model assumptions are better established by analysis of the data in the energy range 20-40 MeV. While the present analysis has taken advantage of both a new set of accurate measured cross sections around 14 MeV and the larger data basis fortunately available between 20 and 40 MeV for the Mn and Cu isotopes, the need of additional measurements below as well as above 40 MeV is pointed out. Keywords: 55Mn, 63,65Cu, E$\leq$40 MeV, Neutron activation cross section measurements, Nuclear reactions, Model calculations, Manganese, Copper