Fe
six for Oak.
The fission product ratios
none
Mo??-to-Kr®* and Mo?2 to-Kr°8
calculated for each shot from the sample analytical data are given in Table
3.1,
Also listed are the R-values for Sr 90 and cs!37 from the gross
particulate samples collected from the cloud at the same time,
R-values
characteristic of megaton range detonations are 0.77 for sr?° and 0.90
for cs!37,
Subject to the assumptions inherent in the method, the fission
product ratios give directly that fraction of the total Mo?? formed in the
explosion which was left in the cloud at the time of sampling.
Maultipli-
cation of these numbers by the cloud R-values and division by the device .
R-values convert them to the fractions of the nuclides remaining in the
clouds.
The last step is necessary to correct for the difference in fission
yields between device neutrons and thermal neutrons (see Section 1.2.1).
The samples in the table are identified by aircraft numbers as in Appendix
B, to which reference should be made for further details.
The calculated fractions of Mo??, Sr?9 and Cs!37 in the cloud, based
on the Kr88 fission product ratios, are plotted as a function of time in
Figures3.1, 3.2 and 3.3.
Kr®8 was not determined on the 27-hour samples
from Walnut and Oak due to its low counting rate at that time.
The points
on the curves for these shots at 27 hours are based on the Mo?9-to-Kr 98
fission product ratios corrected by the Kr 3846.41785 ratio at 12 hours.
On
Koa the late-time fission ratio is extrapolated and the Sr?9 and C3137 fractions
NE Lit
SAN BRU
70
7d