Numerical and experimental results of the operational neutron dosemeter "Saphydose-n".
T. Lahaye, Q. Chau, S. Ménard, M. Ndontchueng-Moyo, T. Bolognese-Milsztajn, A. Rannou, Ninth Symposium on Neutron Dosimetry, 28-09/03-10/2003, Delft.
Personal neutron dosimetry represents one of the current difficulties of neutron worker monitoring. The development of a new neutron dosemeter generation was necessary to comply with the recommendations of Publication No. 60 by the ICRP(1) and to implement neutron active dosimetry methods. Since 1993, the Institute for Radiological Protection and Nuclear Safety (IRSN) has lead, in association with Electricité de France (EDF), a R&D study of a neutron personal electronic dosemeter(2,3). The technology transfer towards the SAPHYMO® company was started in 1998. The dosemeter trademark is "Saphydose-N". This compact device allows the estimation of the personal dose equivalent Hp (10,a) in mixed neutron-photon radiation fields. Saphydose-N is suitable for any nuclear facility without prior knowledge of the neutron spectrum or of the neutron-gamma ratio. Monte-Carlo simulations were performed with the MCNP 4C code(4) in order to optimise the components of the detector (converters, shields). Simultaneously, experiments were performed in different neutron fields (mono-energetic, ISO sources ..). At the beginning of the year 2002, a Saphydose-N was tested under radiation following the IEC 1323(5) standard’s recommendations for active personal neutron dosemeters. The measurements with the manufactured dosemeter were performed at PTB (Physikalisch-Technische Bundesanstalt) in mono-energetic neutron fields and at IRSN in neutrons fields generated by a thermal facility, radionucleide ISO(6) sources (AmBe, 252Cf, (252Cf+D2O)/Cd) and realistic spectrum (CANEL/T400). The manufactured dosemeter Saphydose-N was also tested during measurement campaigns of the European program EVIDOS(7) (supported by the European Commission). This paper presents the results of the homologation, experiments and simulations.