606
KURODA, KAURANEN, PALMER, MENON, AND FRY
US.
a
TEST SERIES
mi
wy
.
i.
|
|
USSR TEST SERES
my
i
oars.
*
W8 TS
|
103
MT
10?
1405,/905,
NUCLIDE RATIO
10!
10°
107!
1072
1073
S'O'N,
D
]
FiM
|
,
A.M
SITOIN, DILJLFIMIA
|
]
Fig. 2—'*Ba/9Sr and °Ba/®Sr in individual rain samples at Fayetteville, Ark.
This difference might be an indication of nonuniform mixing of
these fission products due to fractionation. Let us compare the mass
chains 89, 90, and 140:
8
B~
Kr
Bo
89
B™
89
5
ger —. 37RD —- 3g0F ——-»
3.2 min
15 min
50.4 days
33 sec
B—
B—
Rb —.
Sr 2
2.9 min
28 years
W0Xe___ H9cg_MBa
B~
16 sec
B87
66 sec
B-
12.8 days
In the case of the mass chains 89 and 90, the most probable fragment charge lies near Z= 36, which corresponds to the gaseous element krypton; hence the fission products would exist predominantly as
the gaseous precursors "Kr and “Kr shortly after a nuclear explosion.