Passage of positrons through substances with point defects

Transmission of positrons through defect materials with account of their capture (or interaction) by defects is considered. The coordinate-time balance equation for the flux of moving positrons is obtained. Having determined from the equation the fluxes of moving positrons and those captured by the defects, it is possible to connect the intensity of photons observed in the experiment (by lifetime or angular correlation) with the defect concentration. The result does not contradict with the theoretical calculation