| 摘要 |
PROBLEM TO BE SOLVED: To provide a cerium fluoride single crystal having high gamma-ray-resistance, used for energy measurement of a high-energy radiation or for a radiation medical device or the like.SOLUTION: A cerium fluoride single crystal having high gamma-ray-resistance in which an initial internal transmittance at 340 nm is 99%/cm or more, and the internal transmittance at 340 nm after elapse of 100 days after irradiation of a gamma ray of 1,000 kGy is 99% or more of the initial internal transmittance, is obtained by subjecting the cerium fluoride single crystal to which a barium fluoride is added as much as 0.1-1 mol% to a heat treatment at a temperature of 800°C or higher and below a melting point.SELECTED DRAWING: Figure 2 |
