Radiation Effects in CaF2:Sm

Abstract

The absorption spectra of Sm³⁺ and Sm²⁺ in CaF₂ have been measured from 200–800 mμ at room and liquid‐nitrogen temperatures. A strong divalent absorption band at 620 mμ has an effective oscillator strength of 1.1×10⁻². This band has been used to study the reduction of CaF₂:Sm³⁺ by ionizing radiation. For some samples, the reduction is as large as 50%. The kinetics of the reduction is obscured due to the presence of oxygen and other crystal defects. The data do indicate that the charge compensator for Sm³⁺ in CaF₂ is an interstitial F⁻ ion.