Towards a radon-in-water primary standard at LNHB.

Despite widespread radon-in-water measurements, no primary radon-in-water standards currently exist. This work aims to bridge this gap by developing a system to produce radon-in-water reference materials. The system relies on cryogenic, loss-free transfer of radon, which is standardized through defined solid angle measurements, to a radon standard in water.

Simulation of the response of an ionization chamber to Bi emission. Application to the measurement of Rn.

PENELOPE simulations of a Vinten ionization chamber (IC) were performed to investigate the influence of the thickness of glass-ampoules used in Rn standardization. The simulation reveals a non-negligible variation of the energy deposited in the chamber gas region (which may induce a proportional variation of the measured current) when considering the β transition emissions of the daughters of Rn. This reinforces the idea of using a specialist container (made of metal to preserve the integrity of the container) that would circulate between the metrology laboratories in the context of international comparison exercises using the BIPM international reference system (SIR).

[Precariousness and diabetes: prevention using networks].

Precariousness and diabetes: prevention using networks. This article describes the impact of deprivation on prevalence of diabetes and the importance to integrate the socioeconomic aspect of patients while treating a chronic disease such as diabetes which involves everyday gestures and behaviours. Intervention studies demonstrated that incidence of diabetes can be decrease and with alternatives approaches, patients with diabetes can develop coping skills.

Advancements in NORM metrology - Results and impact of the European joint research project MetroNORM.

The results of the three years European Metrology Research Programme's (EMRP) joint research project 'Metrology for processing materials with high natural radioactivity' (MetroNORM) are presented. In this project, metrologically sound novel instruments and procedures for laboratory and in-situ NORM activity measurements have been developed. Additionally, standard reference materials and sources for traceable calibration and improved decay data of natural radionuclides have been established.

Residual radioactivity of treated green diamonds.

Treated green diamonds can show residual radioactivity, generally due to immersion in radium salts. We report various activity measurements on two radioactive diamonds. The activity was characterized by alpha and gamma ray spectrometry, and the radon emanation was measured by alpha counting of a frozen source.

Photon emission intensities in the decay of U-235.

New measurements of photon emission intensities in the decay of U-235 were performed. Source was prepared by deposition of a U-235 solution on glass plate. Standardization was carried out by defined solid angle alpha counting, giving the reference activity with 0.

Comparison of digital signal processing modules in gamma-ray spectrometry.

Commercial digital signal-processing modules have been tested for their applicability to gamma-ray spectrometry. The tests were based on the same n-type high purity germanium detector. The spectrum quality was studied in terms of energy resolution and peak area versus shaping parameters, using a Eu-152 point source.

Design of an electrochemically assisted radiation sensor for α-spectrometry of actinides traces in water.

We describe a new approach for the detection and identification of actinides at low activity levels directly in aqueous solution. The measurement consists initially, in immobilizing alpha emitters in the form of insoluble hydroxides onto the entrance window of an immersed alpha particles detector. For this, a boron doped diamond detector window is negatively polarized to produce a basic layer on its surface by water decomposition.

Validation of efficiency transfer for Marinelli geometries.

In the framework of environmental measurements by gamma-ray spectrometry, some laboratories need to characterize samples in geometries for which a calibration is not directly available. A possibility is to use an efficiency transfer code, e.g.

On scattering effects for volume sources in low-energy photon spectrometry.

In this study, different aspects of the Compton scattering inside volume sources are illustrated using experimental approach and Monte Carlo simulation. For the low-energy range (below 100 keV) scattered events represents around 30% of the whole spectrum. Influence of the source-detector geometry is discussed.

Coincidence summing corrections applied to volume sources.

The numerical calculation of coincidence summing corrections requires both the total and full-energy peak efficiencies to be included in the corrective factors. Moreover, in the case of volume sources, the coincidence probability depends on the position of the photon emission inside the radioactive sample, thus it is necessary to calculate the coincidence summing corrective factors by integrating the elemental contributions for the entire volume. The software ETNA calculates coincidence summing corrective factors according to a deterministic method, for volume sources, two approaches are included in the software: the "simplified" calculation uses directly the efficiency of the volume source like in the case of point source, and the "complete" calculation performs the volume integration.