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研究了纯α Al2 O3单晶的热释光发光曲线和三维发光谱 ,以及光释光衰变曲线 ,对它们的发光机理和剂量学特性进行了分析和讨论 .实验观察到α Al2 O3单晶 β射线照射后立即测量的热释光发光曲线 ,有峰温为 76℃和 2 0 7℃两个发光峰 .经γ射线照射数小时后测量的三维发光谱 ,只有峰温 2 0 7℃波长为 4 16nm发光峰 ,它与α Al2 O3:C晶体的发光波长基本相同 ,是受热激发到导带的电子与F+ 心复合所生成的F心激发态 3P跃迁至基态 1S发的光 .用热释光动力学方程拟合不同照射剂量的发光曲线 ,2 0 7℃发光峰的峰温基本不随剂量而变化 ,形状因子 μg 的平均值为 0 4 15± 0 0 0 1,该发光峰的剂量响应为线性—亚线性 ,表明它基本符合一级动力学模型所预言的发光峰 .实验还测定了纯α Al2 O3单晶辐照不同剂量后 ,4 70nm波长激发的光释光衰变曲线 .用两个指数衰变函数拟合光衰变曲线得到的衰变时间常数τ1 (平均值为 2 6 3± 0 0 7s)基本不随剂量而变化 ,而τ2 则在 0 12至 12Gy范围内有明显下降趋势 ,大于 12Gy时无明显变化 ,约 75s.时间常数τ1 对应的光释光强度和吸收剂量的关系为线性—亚线性 .
The thermoluminescence luminescence curve, three-dimensional luminescence spectrum and light-induced decay curve of pure α Al 2 O 3 single crystal were studied, and their luminescence mechanism and doping characteristics were analyzed and discussed. It was observed that α Al 2 O 3 single crystal β The thermoluminescence luminescence curve measured immediately after the irradiation with two peaks of peak temperature of 76 ℃ and 270 ℃ .The three-dimensional luminescence spectrum measured after γ-ray irradiation for several hours, only the peak temperature of 270 ℃ is 4 16nm luminescence peak, which is the same as the emission wavelength of α Al 2 O 3: C crystal, which is excited by the thermal conduction to the F + Photodynamic equations were fitted to the luminescence curves of different irradiation doses. The peak temperature of the peak at 207 ℃ did not change with the dose, and the average value of the shape factor μg was 0 4 15 ± 0 0 0 1. The dose response Is linear-sublinear, indicating that it is basically in line with the first-order kinetic model of the predicted emission peak.The experiment also measured the pure α Al 2 O 3 single crystal irradiation at different doses, 4 70nm wavelength excitation light-induced decay curve with two Exponential decay function fitting light decay curve The decay time constant τ1 (mean value of 2 6 3 ± 0 0 7s) did not change with dose basically, while τ2 decreased obviously in the range of 0 12 to 12Gy, and no significant change was observed at 12Gy, about 75s. The relationship between the optical emission intensity and the absorbed dose corresponding to the constant τ1 is linear-sublinearity.