ABSTRACT
Theoretically, it was possible to calculate an approximate yield of plutonium in the reactor. Within a few years the knowledge of its actual yield was experimentally improved at the radiochemical plant. Taking into account the 2.3-day half-life of 2 3 9 Np, in the first years the uranium slugs irradiated in reactor A were kept for a period of 10-20 half-lives of 2 3 9 Np before the delivery to the radiochemical plant, to allow all neptunium to pass to plutonium. During this procedure the total radioactivity accumulated in the uranium slugs decreased many times. At the radiochemical plant, special tanks were provided to keep uranium and plutonium-bearing solutions for additional 2 3 9 Np decay [43].
