title: A new low-level gamma-ray spectrometry system for environmental radioactivity at the underground laboratory Felsenkeller.
abstract: A low-level gamma-ray spectrometry system, based on an HPGe-detector with 92% relative efficiency recently installed in the underground laboratory Felsenkeller at 110 m water equivalent (w.e.) depth, is described. The integral background count rate normalised to the Ge-crystal mass in the energy range from 40 keV until 2.7 MeV of 0.034 s(-1)kg(-1) has been achieved by careful material selection of the detector construction material, a graded shielding construction and effective radon suppression. The detector is highly suitable for the effective surveillance of water for human consumption with decision thresholds for (226)Ra and (228)Ra in the order of some mBq L(-1).
authors.affiliation: Verein für Kernverfahrenstechnik und Analytik Rossendorf e.V. (VKTA), P.O. Box 510119, D-01314 Dresden, Germany. matthias.koehler@vkta.de
authors.forename: M
authors.initials: M
authors.lastname: Köhler
authors.forename: D
authors.initials: D
authors.lastname: Degering
authors.forename: M
authors.initials: M
authors.lastname: Laubenstein
authors.forename: P
authors.initials: P
authors.lastname: Quirin
authors.forename: M-O
authors.initials: MO
authors.lastname: Lampert
authors.forename: M
authors.initials: M
authors.lastname: Hult
authors.forename: D
authors.initials: D
authors.lastname: Arnold
authors.forename: S
authors.initials: S
authors.lastname: Neumaier
authors.forename: J-L
authors.initials: JL
authors.lastname: Reyss
mesh_terms: D006801:Humans; D007753:Laboratories; D011886:Radon / Q000032:analysis*; D013051:Spectrometry, Gamma / Q000295:instrumentation* / Q000379:methods; D014867:Water / Q000032:analysis; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D014875:Water Pollutants, Radioactive; D014867:Water; D011886:Radon