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arXiv · 1207.6716

Characteristics of Signals Originating Near the Lithium-Diffused N+ Contact of High Purity Germanium P-Type Point Contact Detectors

The MAJORANA Collaboration·E. Aguayo·M. Amman·F. T. Avignone III·A. S. Barabash·P. J. Barton·J. R. Beene·F. E. Bertrand·M. Boswell·V. Brudanin·M. Busch·Y-D. Chan·C. D. Christofferson·J. I. Collar·D. C. Combs·R. J. Cooper·J. A. Detwiler·P. J. Doe·Yu. Efremenko·V. Egorov·H. Ejiri·S. R. Elliott·J. Esterline·J. E. Fast·N. Fields·P. Finnerty·F. M. Fraenkle·A. Galindo-Uribarri·V. M. Gehman·G. K. Giovanetti·M. P. Green·V. E. Guiseppe·K. Gusey·A. L. Hallin·R. Hazama·R. Henning·E. W. Hoppe·M. Horton·S. Howard·M. A. Howe·R. A. Johnson·K. J. Keeter·M. F. Kidd·A. Knecht·O. Kochetov·S. I. Konovalov·R. T. Kouzes·B. D. LaFerriere·J. Leon·L. E. Leviner·J. C. Loach·Q. Looker·P. N. Luke·S. MacMullin·M. G. Marino·R. D. Martin·J. H. Merriman·M. L. Miller·L. Mizouni·M. Nomachi·J. L. Orrell·N. R. Overman·G. Perumpilly·D. G. Phillips II·A. W. P. Poon·D. C. Radford·K. Rielage·R. G. H. Robertson·M. C. Ronquest·A. G. Schubert·T. Shima·M. Shirchenko·K. J. Snavely·D. Steele·J. Strain·V. Timkin·W. Tornow·R. L. Varner·K. Vetter·K. Vorren·J. F. Wilkerson·E. Yakushev·H. Yaver·A. R. Young·C. -H. Yu·V. Yumatov
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Abstract

A study of signals originating near the lithium-diffused n+ contact of p-type point contact (PPC) high purity germanium detectors (HPGe) is presented. The transition region between the active germanium and the fully dead layer of the n+ contact is examined. Energy depositions in this transition region are shown to result in partial charge collection. This provides a mechanism for events with a well defined energy to contribute to the continuum of the energy spectrum at lower energies. A novel technique to quantify the contribution from this source of background is introduced. Experiments that operate germanium detectors with a very low energy threshold may benefit from the methods presented herein.

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The MAJORANA Collaboration, E. Aguayo, M. Amman, F. T. Avignone III, A. S. Barabash, P. J. Barton, J. R. Beene, F. E. Bertrand, M. Boswell, V. Brudanin, M. Busch, Y-D. Chan, C. D. Christofferson, J. I. Collar, D. C. Combs, R. J. Cooper, J. A. Detwiler, P. J. Doe, Yu. Efremenko, V. Egorov, H. Ejiri, S. R. Elliott, J. Esterline, J. E. Fast, N. Fields, P. Finnerty, F. M. Fraenkle, A. Galindo-Uribarri, V. M. Gehman, G. K. Giovanetti, M. P. Green, V. E. Guiseppe, K. Gusey, A. L. Hallin, R. Hazama, R. Henning, E. W. Hoppe, M. Horton, S. Howard, M. A. Howe, R. A. Johnson, K. J. Keeter, M. F. Kidd, A. Knecht, O. Kochetov, S. I. Konovalov, R. T. Kouzes, B. D. LaFerriere, J. Leon, L. E. Leviner, J. C. Loach, Q. Looker, P. N. Luke, S. MacMullin, M. G. Marino, R. D. Martin, J. H. Merriman, M. L. Miller, L. Mizouni, M. Nomachi, J. L. Orrell, N. R. Overman, G. Perumpilly, D. G. Phillips II, A. W. P. Poon, D. C. Radford, K. Rielage, R. G. H. Robertson, M. C. Ronquest, A. G. Schubert, T. Shima, M. Shirchenko, K. J. Snavely, D. Steele, J. Strain, V. Timkin, W. Tornow, R. L. Varner, K. Vetter, K. Vorren, J. F. Wilkerson, E. Yakushev, H. Yaver, A. R. Young, C. -H. Yu, V. Yumatov. 2012-07-28. Characteristics of Signals Originating Near the Lithium-Diffused N+ Contact of High Purity Germanium P-Type Point Contact Detectors. https://arxiv.org/abs/1207.6716

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