Quantitative Comparison of Liquid Scintillation Counting Spectra

The quantitative comparison of liquid scintillation counting spectra and subsequent identification of regions of statistically significant differences can be very useful in activity determination by liquid scintillation counting (LSC). The objective of this work is to present two approaches for quantitative comparison of LSC spectra and to evaluate their performance. The proposed techniques are based on statistical analysis of the difference spectrum of the two spectra. The first algorithm employs thresholding to evaluate the statistically significant differences, while the second one employs the Grubbs' statistical test for outliers combined with a prior application of a variance stabilizing transformation. The performance of the two methods is tested with experimental data obtained in dedicated measurement with a LS counter. We conclude that the proposed techniques show good potential for identification of regions of statistically significant differences between liquid scintillation spectra and are applicable in problems related to comparison and analysis of LSC spectra.