Relationship Between Counting Rate and Source Strength

5 RELATIONSHIP BETWEEN COUNTING RATE AND SOURCE STRENGTH 

Equation 8.18 rewritten in terms of the true net counting rate r gives the relationship between r and the source strength  

In terms of gross counts G obtained over time and background count B 

The error in the value of S is due to errors in the values of ft, F, e, and the statistical error of r. In many cases encountered in practice, the predominant error is that of r. Then one obtains, from Eq. 8.23, 

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