New evaluation of alpha-decay half-lifew of 190 Pt isotope for the Pt/Os dating system

• Main Authors: Tavares, OAP, Medeiros, EL, TERRANOVA PERSICHELLI, MARIA LETIZIA
• Other Authors: Tavares, O, TERRANOVA PERSICHELLI, Ml, Medeiros, E
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2006
• Subjects: Alpha decay; Natural radioactivity; 190Pt isotope; Pt–Os dating system; Geochronology; Settore CHIM/03 - CHIMICA GENERALE E INORGANICA; Terranova
• Online Access: http://hdl.handle.net/2108/16216

evaluate the half-life of the Pt isotopes. For the important naturally occurring 190Pt isotope, the radiogenic parent in the 190Pt !186Os dating system, the model yielded a half-life-value of (3.7 ± 0.3) · 1011 y. This is comparable to (3.2 ± 0.1) · 1011 y which was obtained in the last direct counting experiment to measure the alpha activity of 190Pt [O.A.P. Tavares, M.L. Terranova, Radiat. Meas. 27 (1997) 19]. A literature survey of available alpha decay half-life values for 190Pt isotope is also reported. The significant discrepancies found between data obtained by direct counting, indirect geological methods and different calculation models are analysed and discussed.