Measurement of the neutron flux at the Canfranc Underground Laboratory with HENSA

TL;DR

This study reports a long-term measurement of neutron flux at the Canfranc Underground Laboratory using HENSA, demonstrating stable operation and providing new flux data consistent with previous shorter measurements.

Contribution

First long-term neutron flux measurement at Canfranc using HENSA, with results showing stability and agreement with prior shorter experiments.

Findings

Neutron flux during Phase 1 was 1.66(2) × 10^{-5} cm^{-2} s^{-1}

HENSA setup demonstrated excellent stability over 1.5 years

Results align with previous measurements using a smaller setup

Abstract

We have performed a long-term measurement of the neutron flux with the High Efficiency Neutron Spectrometry Array HENSA in the Hall A of the Canfranc Underground Laboratory. The Hall A measurement campaign lasted from October 2019 to March 2021, demonstrating an excellent stability of the HENSA setup. Preliminary results on the neutron flux from this campaign are presented for the first time. In Phase 1 (113 live days) a total neutron flux of 1.66(2) $\times$10$^{-5}$ cm$^{-2}$ s$^{-1}$ is obtained. Our results are in good agreement with those from our previous shorter measurement where a reduced experimental setup was employed.