Influence of lattice structure on motion of positrons and electrons through single crystals

Abstract

The emission yield from single crystals doped with β emitters is investigated. In the axis direction, energetic electrons emitted from a lattice position show a peak in yield up to 2.4 times the normal yield, whereas positrons emitted from the same positions show a dip by a factor of 4 from the normal yield. Electrons emitted from interstitial positions show no peak in yield. Energetic electrons transmitted through a thin single crystal experience increased multiple scattering when the incoming beam is aligned with an axis direction. The influence of atomic planes on the motion of electrons and positrons is also investigated. Furthermore, the electron peak and positron dip have been used for the localization of foreign atoms in single crystals.