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DETERMINATION OF THE LIQUID SCINTILLATION COUNTING INEFFICIENCY (WALL EFFECT) FOR ALPHA EMITTERS, USING THE ALPHA-GAMMA ANTICOINCIDENCE METHOD
Published
Author(s)
Ryan P. Fitzgerald, Anne M. Forney
Abstract
The wall effect in liquid scintillation (LS) counting is the loss of efficiency in the case that an alpha-particle hits a surface (wall or air) before depositing enough energy to be detected. We report our measurements of this LS inefficiency using the 4-pi alpha-gamma anticoincidence method with corrections for the presence of gamma-rays, x-rays and electrons during some alpha decays. We derive the Benjamin equation and test the application of this equation to LS alpha counting. Our value for the LS inefficiency is (6 ± 5)10^-5 for a typical low-energy threshold level. This value is consistent with most literature values, but is smaller than the value reported by Cassette (2002) of about 210^-3. We discuss possible reasons for this disagreement.
Fitzgerald, R.
and Forney, A.
(2011),
DETERMINATION OF THE LIQUID SCINTILLATION COUNTING INEFFICIENCY (WALL EFFECT) FOR ALPHA EMITTERS, USING THE ALPHA-GAMMA ANTICOINCIDENCE METHOD, Radiocarbon, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=906829
(Accessed October 16, 2025)