Detection of Escape Peaks in Environmental Gamma Spectrometry
Keywords:
Gamma Spectrometry, NORM, Pair Production, Single Escape, Double Escape.Abstract
Pair production (PP) events are observed with gamma spectrometry when investigated samples emit sufficient numbers of photons with energies greater than 1.022 MeV. Because this condition is not typical of environmental samples, detection of PP is uncommon for environmental radioactivity. Nonetheless, this work experimentally demonstrated the detection of PP for an environmental sample of relatively high amount of the natural, radioactive isotope of potassium 40K, utilizing low background gamma spectrometry with sufficiently long counting times. Such detection was spectrally seen through the escape events of the annihilation photons that typically follow PP.
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