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arXiv · 1803.06999

Characterization of High Purity Germanium Point Contact Detectors with Low Net Impurity Concentration

S. Mertens·A. Hegai·D. C. Radford·N. Abgrall·Y. -D. Chan·R. D. Martin·A. W. P. Poon·C. Schmitt
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Abstract

High Purity germanium point-contact detectors have low energy thresholds and excellent energy resolution over a wide energy range, and are thus widely used in nuclear and particle physics. In rare event searches, such as neutrinoless double beta decay, the point-contact geometry is of particular importance since it allows for pulse-shape discrimination, and therefore for a significant background reduction. In this paper we investigate the pulse-shape discrimination performance of ultra-high purity germanium point contact detectors. It is demonstrated that a minimal net impurity concentration is required to meet the pulse-shape performance requirements.

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S. Mertens, A. Hegai, D. C. Radford, N. Abgrall, Y. -D. Chan, R. D. Martin, A. W. P. Poon, C. Schmitt. 2018-12-02. Characterization of High Purity Germanium Point Contact Detectors with Low Net Impurity Concentration. https://doi.org/10.1016/j.nima.2018.09.012

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