A Sensitive Element for Radiothermoluminescent Dosimeters for Gamma and Neutron Radiations

The paper describes methods of measuring the equivalent dose of mixed gamma and neutron radiation; they are based on the use of radiothermoluminophors which exhibit high sensitivity in the recording of heavy charged particles. The sensitive element of a dosimeter for making such measurements is designed in the form of a disperse system consisting of the luminophor and heat-resistant hydrogenous base. The results of measurements of the basic dosimetric parameters of the element are given: Sensitivity to gamma rays and neutrons as a function of luminophor concentration: The standard deviation of sensitivity in a batch of elements with luminophor-concentration of 300 m g/cm3 is ± 7.4%: The dose characteristic is linear in the equivalent dose range from 50 mrem to 5 krem; Sensitivity of the element to X-radiation with an effective energy of 40 keV is fifteen times higher than its sensitivity to the gamma radiation of 60Co, but the energy dependence obtained with an 0.64 mm lead filter does not exceed ±20% in the 1000 keV - 1.25 MeV energy range-, Dependence of the sensitivity of the element to 1 rem equivalent for measurements in the 50 keV- 4.5 MeV neutron energy range. The tests carried out with the elements confirm that the method can be used extensively for measuring the dose of mixed gamma and neutron radiations in the case of chronic exposure or severe radiation injury. (author)