title: Marked disequilibrium between 234Th and 230Th of the 238U natural radioactive decay chain in IAEA reference materials n. 312, 313 and 314.
abstract: A new laboratory for the spectroscopy of natural radioactivity with a good energy resolution is presented. It consists of two distinct parts equipped, respectively, the first one with a HpGe γ-ray detector, whose setup has been already completed, and the second one with large area Silicon α-ray detectors and a radiochemical section for thin α-samples preparation, whose setup is yet in progress and will be the argument of a separate work. The γ-ray spectrometer was calibrated by means of IAEA Reference Materials n. 312, 313, 314 and 375. A large difference from the predictions of secular equilibrium emerged between the activities of (234)Th and (230)Th in Materials n. 312, 313 and 314.
authors.affiliation: Dipartimento di Geologia e Geofisica dell'Università di Bari, Via Orabona 4, Bari, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Colaianni
authors.forename: G
authors.initials: G
authors.lastname: D'Erasmo
authors.forename: A
authors.initials: A
authors.lastname: Pantaleo
authors.forename: L
authors.initials: L
authors.lastname: Schiavulli
mesh_terms: D002138:Calibration; D007390:International Agencies / Q000592:standards*; D011851:Radioactivity; D012015:Reference Standards; D013051:Spectrometry, Gamma / Q000295:instrumentation*; D013910:Thorium / Q000032:analysis* / Q000592:standards*; D014501:Uranium / Q000737:chemistry*
chemical_list: D014501:Uranium; D013910:Thorium