The composite neut capture decay curve will then be the sum of the decay curves of tea, es, Np239, u240 | and Np240 , 1.@., Be = Ago (02000416270 000431t 4 o-1..77t (3.9) £ 0.006520 2O1L24t 4 0.014607 00495t y+ where A, = Activity due to capture products at time t and Acos Proportionality constant Aug can be determined from the ratio of neutron capture to fission activity measurerents. TABIE 3.1 - Initial tive Actiyities of U“27, 9239 Np239, pitt and upeee , , The Shot 1 decay curve vill then be the sum of Eqe 3.4 and Eqe 3e9. The experimentally determined ratio of uranium capture products to fission products can then be used to find the value of Ago if it is remembered that Ay, has already been determined. A,[250 sl Ay, (250) (3.10) =n 7 O88 0468 Ay(250)-% ao Aggy (Ecye™4*) (3.11) The curve was then normalized (set ecual to 1) to 400 hours, at which time the activity data were knowne The equation for the extrapolation of fission and neutron induced activities to sampling time is then A = 1350 t72+26 4 2200(0,000226e70+00431¢ (3-12) # enbe77t 40.00652e 0 Ol 2hb Yo 01 46070 0049 5t ) This composite curve is showm in Fige Bele * The last term includes the activity of both U 39 240 and Np* 40