Sensitivity of Next-Generation Water-based Neutrino Detectors for Reactor Antineutrino Detection

Nuclear fission reactors are a key source of power generation in many countries worldwide, but come with the potential for nuclear weapons proliferation.
Safeguarding of current reactors through item accountancy is seen as sufficient to prevent this, but new developments in reactor technology pose new risks.
Using the unshieldable antineutrino signal emitted by reactors during the fission process to monitor core operations offers a potential solution.

A test bed facility has been developed to characterise and test new equipment for a large neutrino detector that could be used for non-proliferation.
A programme of testing for Photo-Multiplier Tubes (PMTs) has been undertaken, resulting in a thorough understanding of the inherent dark rate background.

The PMT characterisation was used to inform the design of a mid- to far-field antineutrino monitoring prototype located in Boulby Mine, with its sensitivity to real reactor antineutrino signals in a complex landscape evaluated using Monte Carlo simulations.
A novel event reconstruction-data reduction-analysis chain has been developed to harness the inverse beta decay signal of a positron and neutron pair to extract reactor signals from backgrounds.

This analysis pathway has been compared to an independent pathway, with significant improvements found.
The detector is found to have sensitivity to power reactors over 150 km away, with the use for future non-proliferation applications of neutrino detectors showing potential.
Consideration of a viable path toward the inclusion and application of antineutrino monitoring of reactors for non-proliferation determines that neutrino detectors may have future utility.