The
for U°39 a
239 were derived as in Eqe 3.9. The ratio
of ys activity to Toa)activity, 0.0007, was determined in this
case by a solution of simultaneous equations using actual decay curves
because capture to fission ratios were unayajlable for this shot.
Eowever,
because of its short half-life, U
similarly.
cannot be calculated
The fission activity component wast
Age Ayptts3
(3.15)
where the exponent was cetermined from decay data after 2000 hr.
A few decay determinations from early-interval samples of
Easy, Fox, and George show that a high percentage of activity origina-~
ted prior to Shot 3, probably from Shot 1.
samples follows the relationship:
The decay from these
A=A(t #998)
(3016)
where 998 hr is the time elapsed between Shots 1 and 3 and n is the
Shot 1 decay exponent during this period.
The activity values from the first two 30=nin intervals and
the first 5-min interval were extrapolated to sampling time oy Eqe
3.16.
All other activities were extrapolated using Eq. 3.14 and 3.15.
Shot 3 decay axponents are listed in Table 3.4. A typical
decay curve is shown in Fig. 3.2.
30304
Shot 4
The activities of Shot 4 samples were corrected to sampling
time by the relations
A = Ayt~le4
(3.17)
where 1.4 is the average of the Shot 4 decay exponents.
The decay curves for this shot are more nearly straight lines
on log-log paper than the curves from Shots 1 and 3, indicating that
the neutron capture activities in samples from Shot 4 are small or
absent; therefore, no corrections were made for these neutron capture
activities. Shot 4 decay values are shcwn in Table 3.4 and a typical
curve is illustrated in Fige Bede
30305
Shot
Shot 6 activities were corrected to sampling time by the relationships
A = Ayt 1
(3 18)
The curves show little or no neutron capture activity and no
correction was made for neutron capture activities.
The value of -1.2
is the average of Shot 6 decays. Values of individual samples are
shown in Tables 3.4 and a representative decay curve is illustrated in
Fige Bebe
44