Thermoluminescence of forsterite and fused quartz as a candidate for the extended red emission

Abstract

Thermoluminescence of silicates interesting in interstellar and circumstellar medium after irradiation of gamma-rays and fast neutron is investigated in detail. The silicates are forsterite, orthoenstatite, olivine, quartz, and crystalline silicon. The irradiated enstatite shows weak and broad peaks at 545 and 760 nm. On the contrary, irradiated bulk and powder samples of forsterite show strong and broad peak at 640-660 nm. Although thermoluminescence of bulk-forsterite is very similar to ERE of Red Rectangle, iradiated powdered-forsterite did not reveal any sharp emission features over broad band. Further, possibility of thermoluminescence of crystalline silicon is investigated, which luminescence scarcely appears. It is emphasized that the prominent carrier of ERE is forsterite and fused quartz.