title: Large-area low-level gross alpha ZnS scintillation counting.
abstract: An efficiency of (44+/-2)% is achieved for samples placed directly on a 5 in diameter ZnS scintillator plate, placed on top of a 5 in photomultiplier in a light-tight pot. Background count rate is as low as (9+/-3)h(-1), equivalent to (5+/-2)mBq on 95 cm(2) for a second scintillator face to face or for a high-purity copper disk. Results are displayed continuously and printed on-line. An automatic repetition of measurements permits a measurement of activity as a function of time. From such a function radionuclides such as radon and its decay products may be distinguished from other radionuclides by their half-life in a technically simpler way than by their energy.
authors.affiliation: Radiometrisches Seminar, Universität, D-93040 Regensburg, Germany. henning.philipsborn@physik.uni-regensburg.de
authors.forename: Henning
authors.initials: H
authors.lastname: von Philipsborn
mesh_terms: D001331:Automation; D006207:Half-Life; D007700:Kinetics; D011868:Radioisotopes; D011886:Radon; D012588:Scintillation Counting / Q000295:instrumentation / Q000379:methods*; D013440:Sulfides / Q000032:analysis*; D017967:Zinc Compounds / Q000032:analysis*
chemical_list: D011868:Radioisotopes; D013440:Sulfides; D017967:Zinc Compounds; C031238:zinc sulfide; D011886:Radon