OPTICAL LUMINESCENCE YIELD SPECTRA OF KCL-TL PRODUCED BY CL K-EDGE AND K K-EDGE EXCITATIONS

The yield spectra of XEOL (X-ray Excited Optical Luminescence) on sing le crystal of Tl-activated KCl are reported. The luminescence yield sp ectra excited with x-rays in the energy ranges of ClK- and KK-edges ar e investigated. All the yield spectra show negative jump at the K edge s of Cl and K irrespective of the observation wavelength channels exce pt for the channel of 550 nm. The inversion of the yield spectra can b e understood as the self absorption of the photons produced at the inn er part of the crystal by the color center at the surface by the x-ray irradiation.