Albedo neutron dosimetry

Abstract

The dosimetric properties of the albedo technique are described on the basis of different dosimeter designs applied up to now in personnel monitoring with emphasis on the dose range, reproducibility, energy and directional dependence, γ-ray sensitivity, body distance, and phantom parameters. The main problem in albedo dosimetry is to calibrate the dosimeter in the environs of each neutron source by applying survey measurements, phantom calibrations, or special field data. Recent investigations make use of a single-sphere albedo technique which standardizes the calibration and the on-line computer evaluation for a multi-component dosimeter, in order to establish position-dependent correction factors of the albedo response in stray neutron fields and to interpret the neutron dose equivalent for the energy groups: thermal, epithermal and fast neutrons. Examples of routine monitoring and stray neutron field analysis at various accelerators and reactors are presented.