Error sources for the analysis of doppler broadening in positron annihilation spectra

Abstract

Correction factors for systematic shifts of the second-order moment gamma(2) (linearly related to S(-1)) of the Doppler broadened annihilation gamma ray lineshape are presented. They allow to com pare a2 values obtained under different experimental conditions. The height of the observed peak, the number of keV/channels used and the num ber of channels over which the Doppler broadening dsstribution should be considered are bounded by the “a priori” settled relative uncertainty of a gamma(2)