Sensitivity of an antineutrino monitor for remote nuclear reactor discovery

TL;DR

This paper evaluates the sensitivity of a gadolinium-doped water Cherenkov detector for remote nuclear reactor monitoring, demonstrating potential detection of 3 GW reactors at 150 km within two years.

Contribution

It introduces two novel reconstruction methods and assesses the sensitivity of a kiloton-scale detector for remote reactor detection.

Findings

A 22 m detector can detect ~3 GW reactors at 150 km within two years.

Detector size influences detection timeliness and the ability to monitor smaller or distant reactors.

Sensitivity depends on detector configuration and reactor proximity.

Abstract

Antineutrinos from a nuclear reactor comprise an unshieldable signal which carries information about the core. A gadolinium-doped, water-based Cherenkov detector could detect reactor antineutrinos for mid- to far-field remote reactor monitoring for non-proliferation applications. Two novel and independent reconstruction and analysis pathways have been developed and applied to a number of representative reactor signals to evaluate the sensitivity of a kiloton-scale, gadolinium-doped Cherenkov detector as a remote monitor. The sensitivity of four detector configurations to nine reactor signal combinations was evaluated for a detector situated in Boulby Mine, close to the Boulby Underground Laboratory in the UK. It was found that a 22~m detector with a gadolinium-doped, water-based liquid scintillator fill is sensitive to a $\rm \sim 3~GW_{th}$ reactor at a standoff of $\rm \sim150~km$ within two years in the current reactor landscape. A larger detector would be required to achieve a more timely detection or to monitor smaller or more distant reactors.