β Scribed by D.J.S. Findlay; T.V. Parsons; M.R. Sene
No coin nor oath required. For personal study only.
Samples of chicken, prawns, cheeses and spices were irradiated on the Harwell electron linear accelerator HELIOS at 20 MeV to assess mechanisms for the induction of radioactivity. The induced radioactivity was measured using a lead shielded Ge(Li) gamma-ray spectrometer, and the results were compared with activities calculated on the basis of photoneutron and photoproton reactions induced by real and virtual photons. In general, there was good agreement. Bounds were also placed on the induction of radioactivity by capture of neutrons produced in the food samples themselves. Further, the data were used to assess the effects of a gross malfunction of an electron beam irradiation facility; after 1 day, the specific activity of food samples irradiated to 10 kGy at 20 MeV was approximately 0.01 Bq g-1. In addition, food samples were also irradiated at 10 MeV, and irradiated and control samples were analysed for microbiological burden. Reductions in the microbiological burden of the food samples by factors consistent with those found in previous measurements were found.
π SIMILAR VOLUMES
Explicit expressions are presented for calculating specific activities induced in food by electron and photon irradiation. In addition, sets of calculated values are tabulated for neutron fluxes produced from moderation and thermalisation of photoneutrons generated within the food. Evaluations of t
Samples of beef were irradiated with electrons of approx. 10- and 13.5-MeV energies or with 60Co gamma-ray photons (1.17 and 1.33 MeV). Induced radioactivity was measured with a gamma-ray spectrometer, consisting of a Ge(Li) detector and a multichannel analyzer. No induced radioactivity could be det