【摘要】 我们用吸收光谱与正电子湮没方法研究了辐照LiF中的色心。样品是纯的LiF单晶。用⁶⁰Co的γ射线在室温下照射样品。当剂量的变化范围为1×10⁵rad—1.3×10⁸rad时,LiF晶体中出现了F、F₂、F₂⁺、F₃、F₄、R₁和R′等色心,由于受光谱仪波长范围的限制,F₂^-未观察到。当照射剂量小于1×10⁶rad时,我们得出F-心浓度、S-参数的相对变化是剂量平方根的线性函数。然而,当剂量大于1×10⁶rad,由于F-聚集心的出现,S-参数正比于照射剂量的对数。更多还原

【Abstract】 The color centers in irradiated LiF are investigated by absorption spectrum and positron annihilation. The samples are pure LiF single crystal, which are irradiated with y-ray of 60Co at room temperature. When the dose varies in the range 1 × 10s rad - 1.3 × 108 rad, the F, F2, F2+ F3, F4, R, and R’ color centers appear in the LiF crystal. The F2- is not observed because it is limited by wavelenth range of used spectrometer. At irradiation dose lesser then 1 × 106 rad, we obtained that the concentration of F-center and the relative change in S - parameter are a linear function of the spuare root of the irradiation dose. However, at the dose larger then 1 × 106 rad, the change of the S -parameter is proportional to the logarithm of irradiation dose due to the appearance of F aggregate centers.更多还原