Reducing 68Ge Background in Dark Matter Experiments

Kouzes, Richard T. ; Orrell, John L.

关键词: ASTROPHYSICS;    FOCUSING;    GE SEMICONDUCTOR DETECTORS;    GERMANIUM;    MINING;    NONLUMINOUS MATTER;    PROCESSING;    RADIOISOTOPES;    GERMANIUM 68 dark matter;    HPGe;    Ge68;    underground science;   

DOI  :  10.2172/1033079
RP-ID  :  PNNL-20269
PID  :  OSTI ID: 1033079
Others  :  TRN: US201202%%631

学科分类：天文学(综合)

美国|英语

来源: SciTech Connect

【 摘 要 】

Experimental searches for dark matter include experiments with sub-0.5 keV-energy threshold high purity germanium detectors. Experimental efforts, in partnership with the CoGeNT Collaboration operating at the Soudan Underground Laboratory, are focusing on energy threshold reduction via noise abatement, reduction of backgrounds from cosmic ray generated isotopes, and ubiquitous environmental radioactive sources. The most significant cosmic ray produced radionuclide is 68Ge. This paper evaluates reducing this background by freshly mining and processing germanium ore. The most probable outcome is a reduction of the background by a factor of two, and at most a factor of four. A very cost effective alternative is to obtain processed Ge as soon as possible and store it underground for 18 months.