Positron thermalization as quantum statistical process

Abstract

The positron thermalization process is considered by the non-equilibrium statistical operator method. Kinetic equations describing the slowing-down of the fast positrons are given in the second order of the positron-medium interaction. Thermalization with account of the positronphonon scattering is analyzed in detail in that case when the phonon subsystem may be in tho, non-equilibrium state. Estimations show that in metals the positrons can be completely thermalize ed due to positron-phonon interaction even at very low temperatures -up to liquid helium temperature.BecHoro cTaTmmmecKoro onepa-ropa. KmeTusecKae ypaBHeHHtI, onHcMsaIowie s a~e n -IIO~~ITPOHOB co cpenot . AeTamHo a~a n u a~p y e~c f l cnynat