A new thoron atmosphere reference measurement system

Benoit Sabot (1) , Sylvie Pierre (1) , Nathalie Michielsen (2) , S. Bondiguel (2) , Sylvain Bondiguel (2) , Philippe Cassette (1)

1 LNHB (CEA, LIST) - Laboratoire National Henri Becquerel (CEA, LIST)
2 IRSN/PSN-RES/SCA/LPMA - Laboratoire de physique et de métrologie des aérosols

A new thoron reference ((220)Rn) in air measurement system is developed at the LNE-LNHB with the collaboration of the IRSN. This measurement system is based on a reference volume with an alpha detector which is able to directly measure thoron and its decay products at atmospheric pressure. In order to improve the spectrum quality of the thoron progenies, we have applied an electric field to catch the decay products on the detector surface. The developed system is a portative device which can be used to measure reference thoron atmosphere such as the BACCARA chamber at IRSN (Picolo et al., 1999). As this system also allows the measurement of radon ((222)Rn) in air, it was validated using the radon primary standards made at the LNE-LNHB. This thoron measurement system will be used, at IRSN, as a reference instrument in order to calibrate the thoron activity concentration in the BACCARA facility.

Mots clés: Primary standard; Radon; Rn-220; Rn-222; Thoron; air measurement; alpha detector; spectrum; decay products; portative device; reference instrument; metrology; calibration; activity concentration; radioactivity; ionizing radiation; instrumentation; nuclear instrumentation; alpha-rays; detector; reference source

Domaines: Instrumentations et Détecteurs [physics.ins-det]; Physique Nucléaire Expérimentale [nucl-ex]

Benoit Sabot, Sylvie Pierre, Nathalie Michielsen, S. Bondiguel, Sylvain Bondiguel, et al.. A new thoron atmosphere reference measurement system. Applied Radiation and Isotopes, 2016, 109, pp.205 - 209. ⟨10.1016/j.apradiso.2015.11.055⟩. ⟨hal-01897022⟩