singleelectron events and 0{\nu}{\beta}{\beta} events in CdZnTe: A Monte Carlo simulation study
Abstract
In neutrinoless double beta (0{\nu}{\beta}{\beta}) decay experiments, the diversity of topological signatures of different particles provides an important tool to distinguish double beta events from background events and reduce background rates. Aiming at suppressing the singleelectron backgrounds which are most challenging, several groups have established Monte Carlo simulation packages to study the topological characteristics of singleelectron events and 0{\nu}{\beta}{\beta} events and develop methods to differentiate them. In this paper, applying the knowledge of graph theory, a new topological signature called REF track (Refined EnergyFiltered track) is proposed and proven to be an accurate approximation of the real particle trajectory. Based on the analysis of the energy depositions along the REF track of singleelectron events and 0{\nu}{\beta}{\beta} events, the REF energy deposition models for both events are proposed to indicate the significant differences between them. With these differences, this paper presents a new discrimination method, which, in the Monte Carlo simulation, achieved a singleelectron rejection factor of 93.8+0.3 (stat.)% as well as a 0{\nu}{\beta}{\beta} efficiency of 85.6+0.4 (stat.)% with optimized parameters in CdZnTe.
 Publication:

arXiv eprints
 Pub Date:
 January 2016
 arXiv:
 arXiv:1601.06300
 Bibcode:
 2016arXiv160106300Z
 Keywords:

 Physics  Instrumentation and Detectors;
 High Energy Physics  Experiment
 EPrint:
 v.3 14 pages, 12 figures, accepted by NIM A (DOI:10.1016/j.nima.2017.03.039) v.2 Typo correction and several updates v.1 14 pages, 9 figures