Yelyseev D. Development of ways to improve the scintillation characteristics of a plastic scintillator.

This thesis is devoted to the development of ways to improve the scintillation characteristics of a plastic scintillator (PS), namely to improve the timing characteristics and increase the light output of the PS by changing the charges mobility in the polymer medium and suppressing the excimer channel of excitation energy loss. Approaches to modifying the polymeric base of a plastic scintillator, which allow to suppress the excimer formation in comparison with the traditional matrix - polystyrene have been developed. Polymeric bases with complete absence of excimer channel of excitation energy loss were obtained. The way to improve the timing characteristics of a plastic scintillator scintillation pulse by introducing into the scintillation composition electron-donating additives - triarylamines, which allow to increase the mobility of electrons in the polymeric medium, is proposed. It is shown that the introduction into the polystyrene based scintillation composition triarylamines leads to an improvement in the timing characteristics of the scintillation pulse - reduction of the pulse rise time and improving the plastic scintillator light output. Keywords: plastic scintillator, light output, luminescence, excimer formation, chromophore, scintillation pulse, triarylamine.