Radiation hardness analysis of polysiloxane scintillators for neutrons by means of Ion Beam Induced Luminescence

Ion beam induced luminescence (IBIL) is the analysis of UV–visible luminescence spectra produced by solid samples during irradiation with energetic charged particles. In contrast to processes leading to the production of X-rays, in which the inner atomic shells are involved, visible luminescence is related to the transitions of the outermost electrons involved in chemical bonds of atoms or in network defects. For this reason, IBIL is sensitive to the chemical environment of the elements, to the presence of trace substitutes and to the point defects in the network. Moreover, IBIL can also be used for the study of the radiation hardness of materials. In fact the decay of the luminescence intensity during irradiation is related to the formation rate of defects and broken bonds. Polysiloxane based scintillators with different doped dyes are produced for the detection of fast and slow neutrons. In particular, different blends are analyzed and their scintillation yield is measured with alfa, gamma and neutrons radiations sources. Ion Beam Induced Luminescence (IBIL) analyses are performed in order to analyze the radiation hardness of the different blends and of the different doping dyes. Moreover, the effects of boron compounds on the intensity decrease of the luminescent molecules is investigated.