Study of spectrum hard part of electromagnetic radiation of positrons during transmission through monocrystals

High energy positron radiation spectrum during transmission through monocrystals in the range of emitting particle photon energy is plotted. The analysis is based on calculation of precise matrix elements. It is shown that at 1-10 GeV energy in the considered range quenching of radiation in the oriented crystal in comparison with the case of amorphous target takes place. With positron energy increase the quenching boundary is shifted to the spectrum end so that beginning from the definite energies radiation amplification takes place at the most part of spectrum