Improvement of 93mNb and 103mRh activity measurement methodology for reactor dosimetry

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

Improvement of

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

Observation et modélisation des flux de sub-surface à l’échelle parcelle.

International audienc

La flore des sites truffiers : les apports du projet Systruf

National audienc

Focus sur le test de la stratégie d’hydrométrie participative prévue pour l’été 2017 dans le cadre du projet de recherche HydroPop : vers une hydrologie populaire ?

International audienc

Mise en œuvre d’une plateforme cartographique participative pour le suivi des basses eaux dans les Cévennes (France)

International audienceMobilizing citizens for supporting research is a very widespread action in the field of natural sciences and particularly for obtaining data on the location and counting of plant and/or animal species. This practice is much less common for water resource observation.As part of this study, an online Webmapping platform wasdeveloped to collect data (photos, videos, comments, height values...) from citizens on low flow during the summer period in the Cévennes basin of the Gardon (Département du Gard, France). Volunteers were identified according to 3 profiles to supply the platform; (1) the "reader"profile (limnimetric scale reading), (2) the "expert"profile (with whom a precise protocol has been defined) and (3) a more generic profile ("observer") which during his visit to the studied area will bring up a wide range of observations.This approach and the associated platform were tested during the summer of 2018. Technically, the system works and the approach has proven its relevance. The first results are therefore promising even if it will be necessary to be sustainable in order to continue this approach effectivelyMobiliser les citoyens dans une démarche d’appui à la recherche est une action très répandue dans le domainedes sciences de la nature, tout particulièrement pour l’obtention de données sur la localisation et le comptage d’espèces végétales et/ou animales. Cette pratique est beaucoup moins répandue pour l’observation de la ressource en eau.Dans le cadre de cette étude, une plateforme cartographique en ligne a été développée pour recueillir les données acquises (photos, vidéos, commentaires, valeurs de hauteurs d’eau...), sur les basses eaux, par des citoyens,durant la période estivale dans bassin cévenol des Gardons (département du Gard, France). Des volontairesont été identifiés selon troisprofils pour alimenter la plateforme; (1) le profil «lecteur» (lecture d’échelle limnimétrique);(2) le profil «expert» (avec qui un protocole précis a été défini) et (3) un profil plus générique («observateur») qui lors de sa visite sur la zone étudiée fera remonter des observations. Cette démarche et la plateforme associée ont été testées durant l’été2018. Techniquement, le site fonctionne, mais l’approche doit montrersa pertinence. Les premiers résultats sont prometteurs, même s’il sera nécessaire de les inscrire dans la durée pour poursuivre efficacement cette démarche