Bleaching Properties ofFCenters in KBr at 5°K

Abstract
The bleaching properties of F centers in KBr have been investigated experimentally at 5°K and 78°K. The stability of F centers towards bleaching is dependent on the temperature and mode of formation. Those produced by additive coloration are stable; those produced at room temperature by x-rays bleach slightly; those produced at 78°K by x-radiation show some bleaching; while those produced at 5°K by x-radiation show a large initial instability. Some tentative theoretical conclusions are made.