화학공학소재연구정보센터
Materials Science Forum, Vol.445-6, 483-485, 2004
Apparatus for the measurement of the annihilation-gamma spectra from the annihilation of positrons with electrons in selected core levels
In this paper we present details of the detector electronics used in measuring the Doppler-broadened gamma spectra associated with the annihilation of positrons with individual core levels electrons. Gamma spectra were obtained by measuring the energy of gamma rays time coincident with Auger electrons emitted as a result of positrons annihilating with a selected core level electrons. The energy of the gamma rays was measured using a HPGe detector. The electrons were energy selected using a trochoidal energy analyzer and detected using a micro channel plate. The outputs of the electron and gamma detectors were fed to a fast coincidence circuit that was used to gate the multi-channel analyzer used to acquire the gamma energy spectrum.