True Coincidence Summing Correction in Gamma Spectroscopy

Table 2.3 Count rate of sources of different geometry
All sources have same amount of Eu-152. Aqueous and sand are 13 mm diameter and 20 mm high
Plotting the data graphically as in Figure-2.9 sketches scattered peaks areas for the
distributed sources relative to the point source. This unexpected scatter of points is
not due to the peak area uncertainty, rather it is reminiscent of the scatter on the
close geometry calibration. Certain factors lead to such peaks; the Eu-152 in the point
source, on the average, is closer to the detector than in the distributed sources. The
scatter represents the difference in TCS between the two source geometries.
Moreover the difference between the aqueous and sand matrix sources can, in
addition to self-absorption, be attributed to the lower TCS in the sand source
because of absorption of the Sm X-rays by the sand.
Figure 2.9 Relative peak areas for sources of different geometry and density [10]
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