Gadolinium study for a water Cherenkov detector

TL;DR

This paper discusses the development of a gadolinium-enhanced water Cherenkov detector to improve neutrino detection sensitivity, detailing ongoing R&D efforts including material testing, light measurements, and neutron tagging.

Contribution

It presents the first comprehensive R&D results for Gd doping in large water Cherenkov detectors, including material compatibility and neutron detection efficiency improvements.

Findings

Gd doping enhances neutron capture detection in water Cherenkov detectors.

Successful material soak tests indicate Gd solution compatibility.

Preliminary neutron tagging efficiency measurements show promising results.

Abstract

Modification of large water Cherenkov detectors by addition of gadolinium has been proposed. The large cross section for neutron capture on Gd will greatly improve the sensitivity to antielectron neutrinos from supernovae and reactors. A five-year project to build and develop a prototype detector based on Super-Kamiokande (SK) has started. We are performing various studies, including a material soak test in Gd solution, light attenuation length measurements, purification system development, and neutron tagging efficiency measurements using SK data and a Geant4-based simulation. We present an overview of the project and the recent R&D results.