Photographic Methods of Measuring Slow Neutron Intensities

Abstract

The relative slow neutron sensitivities of β‐sensitive emulsions, x‐ray film‐indium foil combinations, and boron‐loaded plates were investigated. Since the detection efficiency depends upon the neutron energy, experiments were made with epithermal, thermal, and cold neutrons. β‐sensitive emulsions and x‐ray‐indium combinations are about equally useful for the detection of epithermal neutrons. B¹⁰ loaded plates, which are best for the detection of thermal and cold neutrons, have the following advantages: very low neutron intensities can be measured by microscopic counting of α‐tracks, neutrons can be counted in the presence of β‐and γ‐radiation, the number of α‐tracks is essentially independent of the development conditions, and a wide range of neutron intensities can be measured with a single plate.