The Majorana Demonstrator Status and Preliminary Results

Journal Article · 16 May 2018 · EPJ Web of Conferences (Online)

DOI: https://doi.org/10.1051/epjconf/201817801006 · OSTI ID:1455001

Yu, C. -H.; Alvis, S. I.; Arnquist, I. J.; Avignone, F. T.; Barabash, A. S.; Barton, C. J.; Bertrand, F. E.; Bode, T.; Brudanin, V.; Busch, M.; Buuck, M.; Caldwell, T. S.; Chan, Y. -D.; Christofferson, C. D.; Chu, P. -H.; Cuesta, C.; Detwiler, J. A.; Dunagan, C.; Efremenko, Yu; Ejiri, H. ; Elliott, S. R.; Gilliss, T.; Giovanetti, G. K.; Green, M.; Gruszko, J.; Guinn, I. S.; Guiseppe, V. E.; Haufe, C. R.; Hehn, L.; Henning, R.; Hoppe, E. W.; Howe, M. A.; Keeter, K. J.; Kidd, M. F.; Konovalov, S. I.; Kouzes, R. T.; Lopez, A. M.; Martin, R. D.; Massarczyk, R.; Meijer, S. J.; Mertens, S.; Myslik, J.; Othman, G.; Pettus, W.; Poon, A. W. P.; Radford, D. C.; Rager, J.; Reine, A. L.; Rielage, K.; Ruof, N. W.; Shanks, B.; Shirchenko, M.; Suriano, A. M.; Tedeschi, D.; Varner, R. L.; Vasilyev, S.; Vetter, K.; Vorren, K.; White, B. R.; Wilkerson, J. F.; Wiseman, C.; Xu, W.; Yakushev, E.; Yumatov, V.; Zhitnikov, I.; Zhu, B. Z.; Sun, Yang

The MAJORANA Collaboration is using an array of high-purity Ge detectors to search for neutrinoless double-beta decay in ⁷⁶Ge. Searches for neutrinoless double-beta decay are understood to be the only viable experimental method for testing the Majorana nature of the neutrino. Observation of this decay would imply violation of lepton number, that neutrinos are Majorana in nature, and provide information on the neutrino mass. The MAJORANA DEMONSTRATOR comprises 44.1 kg of p-type point-contact Ge detectors (29.7 kg enriched in ⁷⁶Ge) surrounded by a low-background shield system. The experiment achieved a high efficiency of converting raw Ge material to detectors and an unprecedented detector energy resolution of 2.5 keV FWHM at Q_ββ. The MAJORANA collaboration began taking physics data in 2016. Here, this paper summarizes key construction aspects of the Demonstrator and shows preliminary results from initial data.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Los Alamos National Laboratory (LANL)
• Sponsoring Organization: National Science Foundation (NSF); Natural Sciences and Engineering Research Council of Canada (NSERC); Russian Foundation for Basic Research; USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
• Contributing Organization: Majorana Collaboration
• Grant/Contract Number: AC02-05CH11231; AC05-00OR22725; AC52-06NA25396
• OSTI ID: 1455001
• Report Number(s): LA-UR-18-22409
• Journal Information: EPJ Web of Conferences (Online), Journal Name: EPJ Web of Conferences (Online) Vol. 178; ISSN 2100-014X
• Publisher: EDP SciencesCopyright Statement
• Country of Publication: United States
• Language: English