A new method of quench monitoring in liquid scintillation counting: The H number concept

Abstract

The quench level of different liquid scintillation counting samples is measured by comparison of the responses (pulse heights) produced by the same energy electrons in each sample. The electrons utilized in the measurements are those of the maximum energy (E_max) which are produced by the single Compton scattering process for the same energy gamma-rays in each sample. The relation of the E_max response produced in any sample is related to the E_max response produced in an unquenched, sealed standard. The relation, difference in response on a logarithm response scale, is defined as the “H Number,” H#. The H# is related to the counting efficiency of the desired radionuclide by measurement of a set of standards of known amounts of the radionuclide and different amounts of quench (standard quench curve). This report presents the theory of the H# concept. Several of the unique features of the H# method are discussed. Quench curves based upon the H# are compared to other previously used methods of quench monitoring.