“1 Ot pam wo eet RE ~ . 3 = . ina given samole containing the fissicn orsducsts of Puoor rsh .; 9 Oo is necessary to have a theoretical measure of the (Sr? + Sr? W cr CHARTS FCR STRONTIUM IN MIXED FISSICN FRCDUCTS (total fission activity) ratic as a functicn of time. Hunter end Ballou have Gerived aonrcximate exrressions for tetra! fissicn croduct activity as a functicn cf time. in minutes, these equations are: If it is excredced A(t) = (156000)t7*:*° Lday $4 < 4 days A(t) = (200 )t7* i days < t < 100 davs ! rat - 203 7 A(t) = (2=1éx10°)+7> ' a2 +5 - . 100 days ¢ b < 3 vears «60 At 130 days after burst time, Sr°? and Sr°° ccntribute 10% and 7. BS% respectively to fission croduct activity. The ratio ta fir A any time is then calculated from the Sr half lives and the Ait) formulae. This ratio has been rictted in n Fiz. Awl. ™, With a knowledge of the nercent eontribution of each Sr isotove 4h total activity, the cisintesraticn rates of Sr°9 and Sr®? at any time are readily obtained using the A(t) data. The ratic cf Sr7° Sr®? has been clotted from 1-1000 days in this manner in Fig. S=2h ned ee key Le a ee