The feasibility of using a liquid-filled Cerenkov counter of gamma-ray counting of large samples

The feasibility of detecting gamma rays with energies below 1.5 MeV by means of a large-volume liquid-filled Cerenkov counter has been examined, together with the characteristics and limitations of an experimental counter. Various liquids (water, glycerol, sodium iodide solution; and glycerol plus a wavelength shifter) were investigated as possible Cerenkov media. A rectangular counter containing 1.2 liters of the latter medium could detect 10 nCi of 58Co or 59Fe at 10 cm in a counting time of 1000 s.