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arXiv · 1511.00395

Status Update of the MAJORANA DEMONSTRATOR Neutrinoless Double Beta Decay Experiment

Abstract

Neutrinoless double beta decay searches play a major role in determining neutrino properties, in particular the Majorana or Dirac nature of the neutrino and the absolute scale of the neutrino mass. The consequences of these searches go beyond neutrino physics, with implications for Grand Unification and leptogenesis. The \textsc{Majorana} Collaboration is assembling a low-background array of high purity Germanium (HPGe) detectors to search for neutrinoless double-beta decay in $^{76}$Ge. The \textsc{Majorana Demonstrator}, which is currently being constructed and commissioned at the Sanford Underground Research Facility in Lead, South Dakota, will contain 44 kg (30 kg enriched in $^{76}$Ge) of HPGe detectors. Its primary goal is to demonstrate the scalability and background required for a tonne-scale Ge experiment. This is accomplished via a modular design and projected background of less than 3 cnts/tonne-yr in the region of interest. The experiment is currently taking data with the first of its enriched detectors.

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Julieta Gruszko, Nicolas Abgrall, Isaac Arnquist, Frank Avignone III, Alexander Barabash, Fred Bertrand, Adam Bradley, Viktor Brudanin, Matthew Busch, Micah Buuck, Dana Byram, Adam Caldwell, Yuen-Dat Chan, Cabot-Ann Christofferson, Pinghan Chu, Clara Cuesta, Jason Detwiler, Colter Dunagan, Yuri Efremenko, Hiroyasu Ejiri, Steven Elliott, Alfredo Galindo-Uribarri, Tom Gilliss, Graham K. Giovanetti, Johnny Goett, Matthew P. Green, Ian Guinn, Vince Guiseppe, Reyco Henning, Eric Hoppe, Stanley Howard, Mark Howe, Ben Jasinski, Kara Keeter, Mary Kidd, Sergey Konovalov, Richard T. Kouzes, Brian LaFerriere, Jonathan Leon, Jacqueline MacMullin, Ryan Martin, Ralph Massarczyk, Sam Meijer, Susanne Mertens, Christopher OShaughnessy, John Orrell, Alan Poon, David Radford, Jamin Rager, Keith Rielage, R. G. Hamish Robertson, Elisa Romero-Romero, Benjamin Shanks, Mark Shirchenko, Nathan Snyder, Anne-Marie Suriano, David Tedeschi, Jim Trimble, Robert Varner, Sergey Vasilyev, Kai Vetter, Kris Vorren, Brandon White, John F. Wilkerson, Clint Wiseman, Wenqin Xu, E. Yakushev, Chang-Hong Yu, Vladimir Yumatov, Igor Zhitnikov. 2015-11-02. Status Update of the MAJORANA DEMONSTRATOR Neutrinoless Double Beta Decay Experiment. https://arxiv.org/abs/1511.00395

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