crystals have been grown. Their scintillation and radiation resistence properties have been investigated. It was found that some impurities affect on the light output of scintillators greatly
others slightly
and certain impurity not only affect on it slightly
but also enhance the revival ability of heavy radiation damage of BaF
2
. The present results have been interpreted. The model of[F
2
]colour center has been proposed firstly to explain the origin and phenomena of the 220 nm fast component observed in BaF