To calculate the results as shown in Section 3.2.3, the following
constants wre accepted as standard (Reference 6).
Isotope
Natural Abundance
Half-life
cl o,
3.3 x 107
5,720.0 years
a
9.3 x 107
34.1 days
1.41 x 10°
H3
~-
12.4 years
1.06 x 1077
kK
1.12 x 10%
10.7 years
1.23 x 10°
x,133
8.7 x 10%
5.27 days
0.91 x 1078
h, Min7!
2.30 x 10719
The following oackgrounds were chosen as being representative of
the general test area;
Isotope
Background Atoms per
Equivalent Mole Air
cH 0,*
2.2 x 108
x8
Ast
2.0 x 1051
Essentially Zero
KS
Between 10° and 108
at 20,000 feet
*These specific activities reported in los Alamos
Scientifie Laboratory Report, LA~1102, as 180
and 0.03 dis/min.
+Experimentally determined values based on unpub=
lished data.ofHeadquarters, United States Air
Forcei|
}
For LRD B-31 samples taken at
20 degrees to 30 degrees N latitude, values for
x background are taken as 2.4 X 10° atoms per
equivalent mole air.
Methods used to compute atoms per equivalent mole air for a specific
gas of a sample in accordance with separation and counting techniques are
described in Reference 5.
All isotopic quantities reported have been
corrected for decay which occurred during the interval prior to assay.
30