Limits on uranium and thorium bulk content in GERDA Phase I detectors
Abstract
Internal contaminations of U, U and Th in the bulk of high purity germanium detectors are potential backgrounds for experiments searching for neutrinoless double beta decay of Ge. The data from GERDA Phase~I have been analyzed for alpha events from the decay chain of these contaminations by looking for full decay chains and for time correlations between successive decays in the same detector. No candidate events for a full chain have been found. Upper limits on the activities in the range of a few nBq/kg for Ra, Ac and Th, the long-lived daughter nuclides of U, U and Th, respectively, have been derived. With these upper limits a background index in the energy region of interest from Ra and Th contamination is estimated which satisfies the prerequisites of a future ton scale germanium double beta decay experiment.
Cite
@article{arxiv.1611.06884,
title = {Limits on uranium and thorium bulk content in GERDA Phase I detectors},
author = {GERDA collaboration and M. Agostini and M. Allardt and A. M. Bakalyarov and M. Balata and I. Barabanov and L. Baudis and C. Bauer and N. Becerici-Schmidt and E. Bellotti and S. Belogurov and S. T. Belyaev and G. Benato and A. Bettini and L. Bezrukov and T. Bode and D. Borowicz and V. Brudanin and R. Brugnera and A. Caldwell and C. Cattadori and A. Chernogorov and V. D'Andrea and E. V. Demidova and A. di Vacri and A. Domula and E. Doroshkevich and V. Egorov and R. Falkenstein and O. Fedorova and K. Freund and N. Frodyma and A. Gangapshev and A. Garfagnini and P. Grabmayr and V. Gurentsov and K. Gusev and J. Hakemüller and A. Hegai and M. Heisel and S. Hemmer and W. Hofmann and M. Hult and L. V. Inzhechik and J. Janicsko Csathy and J. Jochum and M. Junker and V. Kazalov and T. Kihm and I. V. Kirpichnikov and A. Kirsch and A. Kish and A. Klimenko and R. Kneißl and K. T. Knöpfle and O. Kochetov and V. N. Kornoukhov and V. V. Kuzminov and M. Laubenstein and A. Lazzaro and V. I. Lebedev and B. Lehnert and H. Y. Liao and M. Lindner and I. Lippi and A. Lubashevskiy and B. Lubsandorzhiev and G. Lutter and C. Macolino and B. Majorovits and W. Maneschg and E. Medinaceli and R. Mingazheva and M. Misiaszek and P. Moseev and I. Nemchenok and D. Palioselitis and K. Panas and L. Pandola and K. Pelczar and A. Pullia and S. Riboldi and N. Rumyantseva and C. Sada and F. Salamida and M. Salathe and C. Schmitt and B. Schneider and S. Schönert and J. Schreiner and A. -K. Schütz and O. Schulz and B. Schwingenheuer and O. Selivanenko and E. Shevchik and M. Shirchenko and H. Simgen and A. Smolnikov and L. Stanco and M. Stepaniuk and L. Vanhoefer and A. A. Vasenko and A. Veresnikova and K. von Sturm and V. Wagner and M. Walter and A. Wegmann and T. Wester and C. Wiesinger and M. Wojcik and E. Yanovich and I. Zhitnikov and S. V. Zhukov and D. Zinatulina and K. Zuber and G. Zuzel},
journal= {arXiv preprint arXiv:1611.06884},
year = {2017}
}
Comments
2 figures, 7 pages