Asymmetry of self-energies of electrons and positrons in solids

Abstract We calculate the self-energies of positrons and electrons in solids. Our calculation shows that the imaginary part of the self-energy of positrons is much enhanced in comparison with that of electrons, which explains the recent experiments. The difference of the self-energies of positrons and electrons in solids is explained as the polarization effect of the solid atoms induced by the incident charges.