The Effect of Fast Kr Ion Irradiation on the Optical Absorption, Luminescence, and Raman Spectra of BaFBr Crystals oleh Abdirash Akilbekov, Daurzhan Kenbayev, Alma Dauletbekova, Elena Polisadova, Victor Yakovlev, Zhakyp Karipbayev, Alexey Shalaev, Edgars Elsts, Anatoli I. Popov