title: A new shallow underground gas-proportional counting lab--first results and Ar-37 sensitivity.
abstract: A new ultra-low-background proportional counter was recently developed with an internal volume of 100 cm(3) and has been characterized at pressures from 1-10 atm with P-10 (90% Ar, 10% methane) gas. This design, along with a counting system providing event digitization and passive and active shielding, has been developed to complement a new shallow underground laboratory (30 m water-equivalent). Backgrounds and low-level reference materials have been measured, and system sensitivity for (37)Ar has been calculated.
authors.affiliation: Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA. craig.aalseth@pnnl.gov
authors.forename: C E
authors.initials: CE
authors.lastname: Aalseth
authors.forename: A R
authors.initials: AR
authors.lastname: Day
authors.forename: E S
authors.initials: ES
authors.lastname: Fuller
authors.forename: E W
authors.initials: EW
authors.lastname: Hoppe
authors.forename: M E
authors.initials: ME
authors.lastname: Keillor
authors.forename: B
authors.initials: B
authors.lastname: Leferriere
authors.forename: E K
authors.initials: EK
authors.lastname: Mace
authors.forename: J
authors.initials: J
authors.lastname: Merriman
authors.forename: A W
authors.initials: AW
authors.lastname: Myers
authors.forename: C T
authors.initials: CT
authors.lastname: Overman
authors.forename: M E
authors.initials: ME
authors.lastname: Panisko
authors.forename: A
authors.initials: A
authors.lastname: Seifert
authors.forename: G A
authors.initials: GA
authors.lastname: Warren
authors.forename: R M
authors.initials: RM
authors.lastname: Williams
mesh_terms: D001128:Argon / Q000032:analysis*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005740:Gases / Q000032:analysis*; D007753:Laboratories; D011829:Radiation Dosage; D011868:Radioisotopes / Q000032:analysis*; D015203:Reproducibility of Results; D012588:Scintillation Counting / Q000295:instrumentation*; D012680:Sensitivity and Specificity; D014481:United States
chemical_list: D005740:Gases; D011868:Radioisotopes; D001128:Argon
keywords: Argon-37; Beta spectroscopy; Proportional counter; Shallow underground