LONG-RANGE FALLOUT FROM SEDAN AND SMALL BOY 9¢ Table 1— DISINTEGRATIONS PER MINUTE RATIOS TO *®Mo AT SHOT TIME FOR SEDAN AIR-FILTER SAMPLES ADJUSTED FOR BACKGROUND Source and sample No. s9gr Kaycee, 107 Midwest, 167 Casper ATT, 142 Casper ATT, 157 Casper, 117 Orin, 112 Pepperville, 173 Average Katcoff, thermal 2*U Dolan, 14-Mev 238yy 2.54 90S; Fr iy 103A) 106 By liTCg (1073 (1072), (07) (1074) (1073s (1079 Ba lice 144 (1077) (16 14.0 4.58 2.39 1.92 11.0 0 2.24 4.31 7.25 0 2.16 56.50 2.99 7.00 0 2.10 2.28 4.05 3.97 3.98 0 0 3.39 3.60 2.19 9.59 6.06 8.93 0 0 0 3.12 2.60 2.30 2.77 2.81 2.38 4.7 2.92 6.74 5.26 4.66 4.92 4.06 3.45 2.15 0 0 0 0 15 0 4.32 8.49 2.60 2.57 2.81 0.67 6.06 3.94 0 0 3.04 7.38 2.34 3.01 5.31 4.56 3.13 ~0 ~0 0.0434 0.258 4.4 ~0.43 0.34 0.047 0.0257 0.227 ~8.3 ~0. 0.0248 0.144 3.49 0.545 0.356 0.0268 0.170 0 ~0 1.52 0.287 2.60 4.08 2.48 0 6.27 1. 0. adjusted for the preshot background levels. The theoretical ratios fox the thermal fission of **U by Katcoff? and the 14-Mev neutron fissior of 7817 by Dolan’ are listed in Table 1 for reference. Presumably the production ratios for the Sedan shot would be closer to Dolan’s figures. There are no obvious trends in the data with collection site which suggests that the two levels in the cloud were not fractionated with respect to each other. The zeros in Table 1 represent the situation where no measurable activity was found or where the measured activity was less than the background activity. Comparing the average ratios with Dolan’s values shows a deficiency of zr, ‘'Ce, and “*Ce with respect to **Mo in the airborne particulate matter of the Sedan debris. The radionuclides **sr, “sr, *'y, '*"Cs, and “°Ba have rare gaseous or volatile precursors. Because of their volatile precursors, all of these nuclides show a surplus to **Mo compared to Dolan’s production values. Ruthenium has volatile oxides, and both 'Ru and 06Ru reflect an overabundance with respect to **Mo. However, it is likely that the 103 and 106 mass chains would be present as their respective niobium or molybdenum precursors during the time of radioactive-particle formation. The disintegrations per minute ratios to **Mo at shot time adjusted for background levels are given in Table 2 for the fallout-collector samples. As for the air-filter samples, there is no observable trend with collection site. The Zr behaves as a refractory exhibiting a deficiency in the fallout, whereas the **Sr, sr, *y, !Ru, Ru, '’cs, and ‘°Ba show a surplus. Contrary to the air-filter samples, '!Ce and ‘Ce also show a surplus with respect to Mo although there are several zeros for these nuclides in Table 2, These zeros may be the