On the interaction of glasses with high-energy radiation - Combined ESR and optical studies

This paper will discuss some aspects of the induced physical processes and chemical reactions which are observed when silicate and aluminosilicate gla sses are exposed to UV radiation (248 nm; excimer laser), gamma radiation ( Co-60) and pulses of fast electrons (3.8 MeV). The stimulated emission and absorption of short-lived defects and Cerenkov radiation are, detected in t he optical range between 200 and 800 nm and on the microsecond time scale. Stable hole centres (Si-O-/h(+), Si-O-Al/h(+)) and electron centres (among others Zn+, Cd+, (Fe3+)(-)) are detected by ESR spectroscopy at room temper ature. They show surprising differences in regard to their thermal stabilit y, i.e., the distribution and mean value of their trap depths. Induced abso rption in the UV/VIS range exhibits broad and overlapping bands, some of wh ich can be partially assigned to centres detected by ESR spectroscopy. Ther efore, UV/VIS spectroscopy provides complementary information, an induced a bsorption at 300 nm for example, which has no analogy in ESR measurements.