A SPECTROMETER FOR THE MEASUREMENT OF THE DOPPLER BROADENING OF THE ANNIHILATION LINE WITH EFFICIENT REDUCTION OF BACKGROUND

Following Lynn and the suggestion made by MacKenzie we describe a Dopp ler broadening (DB) spectrometer with efficient reduction of the backg round (BG). The simple experimental set-up achieved a peak to the BG r atio for the annihilation line of the order 1000:1. In this work, atte ntion is given to the problem of the BG correction under the annihilat ion line, which has not been described in the literature. Measurements of Doppler profile of the annihilation line in Ni, Cu and a single cr ystal of Si are presented as an illustration of the advantage of the a pplications of the suggested BG reduction and correction technique.