Determination of 218Po nanometer size distribution in controlled environment by two new systems.
A. Vargas, N. Michielsen, C. Le Moing, M. Rio, G. Tymen, X. Ortega, Natural Radiation Environment, NRE VII, 20-24/05/2002, Rhodes (Greece).
During the European research programme RARAD (1996-1999), the group formed by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) and Brest University (UBO), and the group from the Institut de Tècniques Energètiques at the Technical University of Catalonia (INTE-UPC) have developed new measurement systems for the determination of the radon progeny nanometer size distribution based on diffusion tubes instead of wire screen technique due to a lack of knowledge of the characterisation of the screen diffusion batteries in this small diameter range. Moreover, during this project different deconvolution techniques were checked in an intercomparison study. Thus, an intercomparison with these two systems and different deconvolution algorithms were planned under controlled conditions in a large radon chamber. The influence of radon concentration on size was studied. The data show good agreement in the results with a most probable mean diameter of 0.85 nm, however the influence of environmental conditions such as radon concentration and relative humidity cannot be ascertained.
This work has been done with the collaboration of the Institut de techniques energétiques, Universitat Poitécnica de Catalunya (Spain), the Laboratoire de recherches appliquées (Université de Bretagne, France).