Simulation results of a real-time in water tritium monitor

C.D.R. Azevedo , A. Baeza , E. Chauveau (1) , J.A. Corbacho , J. Díaz , J. Domange (1) , C. Marquet (1) , M. Martínez-Roig , F. Piquemal (1) , J.F.C.A. Veloso , N. Yahlali

1 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan

In this work we present simulation results for a modular tritium in-water real-time monitor. The system allows for scalability in order to achieve the required sensitivity. The modules are composed by 340 uncladed scintillating fibers immersed in water and 2 photosensors in coincidence for light readout. Light yield and Birks’ coefficient uncertainties for low energy beta particles is discussed. A study of the detection efficiency according to the fiber length is presented. Discussion on the system requirements and background mitigation for a device with sensitivity of 100 Bq/L, required to comply with the European directive 2013/51/Euratom, is presented. Due to the low energetic beta emission from tritium a detection efficiency close to 3.3% was calculated for a single 2 mm round fiber.

Mots clés: Tritium in water; Real-time monitor; Nuclear power plant; Environmental safety

Domaines: Instrumentations et Détecteurs [physics.ins-det]

C.D.R. Azevedo, A. Baeza, E. Chauveau, J.A. Corbacho, J. Díaz, et al.. Simulation results of a real-time in water tritium monitor. Nucl.Instrum.Meth.A, 2020, 982, pp.164555. ⟨10.1016/j.nima.2020.164555⟩. ⟨hal-02497859⟩