A Pulse Shape Analysis technique for the MAJORANA experiment

作者：Cooper R J^*; Radford D C; Lagergren K; Colaresi James F; Darken Larry; Henning R; Marino M G; Yocum K Michael

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2011, 629(1): 303-310.

DOI：10.1016/j.nima.2010.11.029

• HPGe detector
• Pulse Shape Analysis
• Background rejection
• Neutrinoless double beta decay

In order to achieve background count rates sufficiently low so as to allow the observation of rare events such as neutrinoless double beta (0 nu beta beta) decay, background suppression techniques are routinely employed. In this paper we present details of a novel Pulse Shape Analysis algorithm, which allows single-site events such as 0 nu beta beta decay to be distinguished from multi-site background events in germanium detectors. The algorithm, which is based on the event-by-event chi(2) fitting of experimental signals to a basis data set of unique single-site pulse shapes, has been developed through simulation studies and tested experimentally using a Broad Energy Germanium detector. It is found experimentally that the technique is able to successfully identify and reject 99% of multi-site events in the single escape peak associated with the gamma decay of Tl-208, whilst maintaining a survival probability of 98% for neutrinoless double-beta-decay-like double escape peak events.

• 出版日期2011-2-11