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241 Am-Be source abstract A measurement campaign has been carried out recently to provide the source intensity and the reference spectra around a neutron irradiation facility based on 241 Am-Be radionuclide source, using the UAB Bonner Sphere Spectrometer. This facility, which consists of a bunker, a container/shielding for the source and an irradiation device that uses an automated remote-controlled system for the source positioning and rotating during the dosimeter irradiation, is intended to be routinely used to check the response of passive dosimeters, namely those based on photo-stimulated imaging plates and solid-state nuclear track detectors. The measurement results, in terms of neutron spectra and global dosimetric quantities (i.e., fluence and ambient dose equivalent rates) at different distances with respect to the 241 Am-Be source, were compared with Monte Carlo simulations using the MCNPX code and a good agreement was observed. An estimation of the un-scattered neutron spectrum directly emitted from the 241 Am-Be source is given as well.

International audience; Polyallyl diglycol carbonate can be polymerized to make solid-state nuclear track detectors, type PN3, that are widely used for neutron dosimetry. Neutrons are detected by the damage trails created by recoil nuclei of the PN3 constituent atoms that are subsequently revealed by either a suitable chemical etching (CE) or electrochemical etching (ECE) process. On the basis of calibration exposures, track density can be related to neutron dose equivalent. The dose equivalent response and the detection level depend on detector material, nature and thickness of the radiator, energy and angle of incidence of the neutron, and the etching process. An automated ECE and reading system has been developed in RaMsEs laboratory. We compare the PN3 neutron dose equivalent response to 241Am–Be neutrons without radiator for both CE and ECE

We describe a fully standalone compact electronic monitor for atmospheric 222 Rn, based on a new CMOS system-on-chip. The electronic board consists of three AlphaRad CMOS chips running in parallel, and it includes a numeric block for data treatment based on a Xilinx programmable gate array. In addition to classical tests (passive detection in a calibrated radon chamber), we present the first results with active collection of radon progeny present as aerosols.