A Small Size Neutron and Gamma Dosemeter with a Single Silicon Surface Barrier Detector

Abstract

A small size, lightweight, real time dosemeter for measuring dose equivalents in mixed neutron and gamma fields was developed. The instrument is based on a single silicon surface barrier detector and can be used as a personnel or as an area dosemeter. Neutrons and gamma rays are discriminated by pulse height analysis. The dosemeter measures dose equivalents above 10-2 mSv, as well as dose equivalent rates above 3 mSv.h-1 and 10-2 mGy.h-1 for neutrons and photons, respectively. It also gives visual and audible alarm signals at a rate proportional to the dose equivalent rate. Theoretical and experimental methods for flattening the dose response as a function of the energy of the neutrons and photons are described. The dependence of the instrument on the angle of incidence for various particle energies is also presented.