Measuring the Ratio of Thermal to Resonance Neutron Densities Using Thick Indium Foils¹

Measurements have been made of the cadmium ratios of indium foils for thicknesses ranging from 0.012 mg/cm² to approximately 100 mg/cm². Correction factors are presented both graphically and in tabular form to determine the ratio of thermal to resonance neutron densities from measurements made with an indium foil of any thickness up to 100 mg/cm².