Tej Singh

Estimation of 99Mo production rates from natural molybdenum in research reactors

Molybdenum-99 is one of the most important radionuclides for medical diagnostics. In 2015, the International Atomic Energy Agency organized a round-robin exercise where the participants measured and calculated specific saturation activities achievable for the 98Mo(n,γ)99Mo reaction. This reaction is of interest as a means to locally, and on a small scale, produce 99Mo from natural molybdenum. The current paper summarises a set of experimental results and reviews the methodology for calculating the corresponding saturation activities. Activation by epithermal neutrons and also epithermal neutron self-shielding are found to be of high importance in this case.

Production of gaseous radiotracers for industrial applications

This paper describes prerequisite tests, analysis and the procedure for irradiation of gaseous targets and production of gaseous radioisotopes i.e. argon-41 ((41)Ar) and krypton-79 ((79)Kr) in a 100MWTh DHRUVA reactor located at Bhabha Atomic Research Center (BARC), Trombay, Mumbai, India. The produced radioisotopes will be used as radiotracers for tracing gas phase in industrial process systems. Various details and prequalification tests required for irradiation of gaseous targets are discussed. The procedure for regular production of (41)Ar and (79)Kr, and assay of their activity were standardized. Theoretically estimated and experimentally produced amounts of activities of the two radioisotopes, irradiated at identical conditions, were compared and found to be in good agreement. Based on the various tests, radiological safety analysis and standardization of the irradiation procedure, necessary approval was obtained from the competent reactor operating and safety authorities for regular production of gaseous radiotracers in DHRUVA reactor.