Atomic and Nuclear Physics
DOE-HDBK-1019/1-93
RADIOACTIVITY
Rev. 0
Page 39
NP-01
Figure 13 Cumulative Production of Sodium-24 Over Time
The amount of sodium-24 present will initially increase rapidly, then it will increase at a
continually decreasing rate until the rate of decay is equal to the rate of production. It is possible
to calculate how much sodium-24 will be present at equilibrium by setting the production rate
(R) equal to the decay rate ( N).
where:
R
= production rate (atoms/second)
= decay constant (second )
-1
N = number of atoms
It is possible to calculate the equilibrium value for sodium-24 being produced at a rate of
1 x 10 atoms/second.
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