Improvement of 93mNb and 103mRh activity measurement methodology for reactor dosimetry
1 CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), CEA-Saclay, Bât 602, PC 111, 91191 Gif-sur-Yvette CEDEX, France
2 CEA, DEN, DER, Laboratoire de Dosimétrie, Capteurs et Instrumentation (LDCI), Cadarache, 13108 Saint Paul-lez-Durance, France
* Corresponding author: firstname.lastname@example.org
Published online: 25 September 2017
Reactor dosimetry is based on the analysis of the activity of irradiated dosimeters, such as 93mNb and 103mRh. The activity measurement of these dosimeters is conventionally performed by X-ray spectrometry, but the low-energy of emitted photons makes it difficult to derive reliable results with low uncertainties. Approaches to improve these characterisations are presented: they include high accuracy efficiency calibration of a HPGe detector using both experiments and Monte Carlo simulation, calculation of corrective factors for the geometry (selfabsorption) and self-fluorescence effects. Improvement of the knowledge of the 103mRh decay scheme is also required and a specific experiment is proposed, including activity measurement of a 103mRh solution by liquid scintillation, and measurement of the photon emission intensities by X-ray spectrometry. A method for calculating coefficients to take into account the self-fluorescence effects in dosimeters is also suggested to improve the uncertainties on activity measurements.
© The Authors, published by EDP Sciences, 2017
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