Development of a primary thoron activity standard for the calibration of thoron measurement instruments

Benoît Sabot (1) , S. Pierre (1) , P. Cassette (1) , N. Michielsen (2) , S. Bondiguel (2)

1 LNHB (CEA, LIST) - Laboratoire National Henri Becquerel (CEA, LIST)
2 IRSN/DSU/SERAC/LPMA - Laboratoire de Physique et de Métrologie des Aérosols

The LNHB and IRSN are working on a reference atmosphere for thoron (Rn-220) instrument calibration. The LNHB, as the national metrology institute for activity measurement in France, has to create a new thoron reference standard in order to estimate with accuracy the thoron concentration of a reference atmosphere. The measurement system presented in this paper is based on a reference volume using an alpha detector, which is able to measure thoron and its decay products to define the thoron concentration of a thoron reference atmosphere. This paper presents the first results with this new system using a well-known radon (Rn-222) atmosphere and a thoron (Rn-220) atmosphere.

Mots clés: radon; alpha detector; thoron; standardization; metrology

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

Benoît Sabot, S. Pierre, P. Cassette, N. Michielsen, S. Bondiguel. Development of a primary thoron activity standard for the calibration of thoron measurement instruments. Radiation Protection Dosimetry, 2015, 167 (1-3), pp.70 - 74. ⟨10.1093/rpd/ncv221⟩. ⟨hal-01865033⟩