MEASUREMENTS OF AIRBORNE RADIONUCLIDES
201
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ac
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7
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0
10
20
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30
40
50
60
Fig. 2
Spectra for 4Cu.
70
CHANNEL NUMBER
absorber. The background shown for the multidimensional detector
system is for an energy diagonal from 0 to 3 Mev and therefore represents the case of O0- to 3-Mev absorption by each detector. These
curves can also be used to compare the background that would be
obtained with two crystals used in a summing arrangement with that
shown for the two crystals in the multidimensional arrangement. In
this case the background at a given energy on the top curve should be
doubled and compared with a point of half that energy on the bottom