# Measurement of the neutron capture cross-section on argon

## TL;DR

This paper presents a precise differential measurement of the neutron capture cross-section on argon using a Time-Of-Flight neutron beam, addressing previous discrepancies and providing critical data for neutrino and dark matter experiments.

## Contribution

It provides the first differential measurement of neutron capture on argon over a specific energy range, improving accuracy for experimental applications.

## Key findings

- Measured cross-section: 673 ± 26 (stat.) ± 59 (sys.) mb
- Differential cross section fitted assuming 1/v dependence
- Addresses previous measurement discrepancies

## Abstract

The use of argon as a detection and shielding medium for neutrino and dark matter experiments has made the precise knowledge of the cross section for neutron capture on argon an important design and operational parameter. Since previous measurements were averaged over thermal spectra and have significant disagreements, a differential measurement has been performed using a Time-Of-Flight neutron beam and a $\sim$4$\pi$ gamma spectrometer. A fit to the differential cross section from $0.015-0.15$\,eV, assuming a $1/v$ energy dependence, yields $\sigma^{2200} = 673 \pm 26 \text{ (stat.)} \pm 59 \text{ (sys.)}$\,mb.