the world-wide fallout of Sr-90 croduced in U. 5S. nuclear detonations.
3. In compiling the data in table 1 of the attached report (Appendix
A) consideration was given to the amounts of fission occuring in the
various components of the weapon and to the variation of Sr~90 fission
yield with weapon type.
Thus, the total Sr-90 produced for a specific
operations, where yields of all the devices detonated may be released,
as unclassified, nanely, Trinity, Japanese bombincss, Crossroads, and
Sandstone would show that the Sr~90 production per kiloton of fission
yield varied for these tests:
From ARC:CLL
From Table 1
Average Sr-90/kt
curles
27 kt
1.7
63
3.5
85
Fission Yield
Trinity
Japanese
Sr-90 production kilocuries
«LL kta
Crossroads
|
O kt
3.3
67
Sandstone
106 kt
12.9
122
Prom data released (18 and 23 kt)
From this variation in average rate of Sr-90 production, it would be
‘4
possible to conclude that the devices in these tests were composed of
The type of fissionable material
used in Trinity, Japanese and Crossroads devices is unclassified.
The
hy sm
different types of fissionable material.
higher average rate of Sr-90 production per kiloton yield for the Sandstone
St A
tests and the known data on Sr-90 production in the fission of U-235 and
Pu~239 would indicate that a large part of the yield of the Sandstone
devices resulted from fission of U-235.
However, it would be impossible on
the basis of this information alone to establish the actual proportion of
the fissionable material which was Ue235.
It is concluded, therefore,
that this information does not reveal any classified weapon design information.
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