Radiation hardness and optical properties of a new Cherenkov radiator, heavy fluoride BaYb 2F 8 doped with various elements, have been studied. The above mentioned crystal has the density of 7 g/cm 3, the radiation length is 1.28 cm and the Molière radius 2.44 cm. High radiation hardness has been demonstrated for BaYb 2F 8 doped with Tm, Pr, Tb.