Total cross section of $^{14}$N+$n$ from 0.1 to 12~MeV

TL;DR

This paper reports a new measurement of the total neutron cross section for $^{14}$N+$n$ from 0.1 to 12 MeV, providing more detailed data to improve nuclear reaction models relevant to astrophysics and nuclear testing.

Contribution

It presents the first detailed experimental data for $^{14}$N+$n$ total cross sections across a broad energy range, especially clarifying the low-energy resonance region.

Findings

Good agreement with previous data at most energies

Identification of a key resonance at 433 keV

Enhanced data quality for nuclear data evaluations

Abstract

The reaction $^{14}$N$(n,p)^{14}$C is one of the main neutron poisons during $s$-process nucleosynthesis. In addition, the reaction provides insight into the yields of atmospheric nuclear weapon testing. Because of their high level of sensitivity, total neutron cross sections provide a great deal of constraint on the modeling of reaction cross sections through the $R$-matrix analyses used for nuclear data evaluations. Yet for $^{14}$N+$n$, only one high sensitivity measurement is available and it lacks detailed information about its experimental conditions and uncertainties. With these motivations in mind, a new measurement of the $^{14}$N+$n$ total cross section has been performed at the nELBE facility. The cross sections were found to be in good agreement with previous data over much of the energy range with the key exception of the lowest energy resonance at a neutron energy of 433 keV.