Role of Trapped and Solvated Electrons in Ps Formation

Role of trapped and solvated electrons in Ps formation is discussed. Combination of thermalized positron with such electrons is possible from the viewpoint of the energy balance and may results in Ps formation. This process proceeds during all e$\text{}^{+}$ lifetime in matter. Fitting of raw experimental e$\text{}^{+}$ - e$\text{}^{-}$ annihilation spectra has to be based on an adequate physical input, which often leads to necessity of nonexponential deconvolution of the spectra. We have interpreted the Ps formation data in polyethylene, ethylene-methylmethacrylate and polymethylmethacrylate in dark and in light vs. time of the measurement and temperature. Parameters characterized accumulation of trapped electrons and their recombination with counter ions and positrons are obtained.