On ionization energy losses of high-energy electron-positron pair in thin targets

The present Letter deals with consideration of high-energy electron-positron pair ionization losses in thin dielectric plate which it traverses after being emitted from substance where it is created. It is shown that in this case the Chudakov effect of reduction of pair energy losses takes place on much larger distance from its creation point than in the case of the pair motion in homogeneous infinite medium. It is demonstrated that due to transition radiation which appears during the pair emission from the substance the ratio of the pair energy losses in two plates situated on different distances from it is noticeably different from the case when the radiation is neglected.