412
SALTER
|
|
“
957 ,/ 905, RATIO
40
+
Oo
|
|
NO
o
10 F—
/
~_N,
=
—_
4
|
|
8
|
w
8
|
8
|
905,, DIS/ MIN PER 10° SCF
&
5
2
4Min/%Sr RATIO
_
/
\
10
60
|
70
|
80
90
ALTITUDE, 1000 FT
|
100
110
Fig. 1—Activity concentrations of 9Sr and activity ratios for *4Mn/
9Sr and ™Zr/9Sr.
1961 debris, therefore, became increasingly difficult as material from
the 1961 and 1962 tests mixed.
The only other shot for which published information indicates
unique tracers exist is Starfish, detonated July 9, 1962. In this 1.4-Mt
detonation, an estimated 250 + 150 kc of !"°Cd (470-day half-life) and
about 25% as much ‘!°"cqd (14-year half-life) were produced.’»® On the
basis of an assumedfission to total yield of 50% and no fractionation, a
'cq/"Sr activity ratio of 3.5 + 2.0 may be calculated. If escape from
the ionosphere occurred for neutron-activation products relative to the
highly charged fission products, then the '°ca/*Sr activity ratio would
be correspondingly smaller.