Multi-site Event Discrimination in Large Liquid Scintillation Detectors

Abstract

Simulation studies have been carried out to explore the ability to discriminate between single-site and multi-site energy depositions in large scale liquid scintillation detectors. A robust approach has been found that is predicted to lead to a significant statistical separation for a large variety of event classes, providing a powerful tool to discriminate against backgrounds and break important degeneracies in signal extraction. This has particularly relevant implications for liquid scintillator searches for neutrinoless double beta decay ($0\nu \beta \beta$) from ${}^{130}$Te and ${}^{136}$Xe, where it is possible for a true $0\nu \beta \beta$ signal to be distinguished from most radioactive backgrounds (including those from cosmogenic production) as well as unknown gamma lines from the target isotope.

20 pages, 10 figures