QUANTITATIVE CALCULATIONS OF ENVIRONMENTAL DOSE RATE AT DIFFERENT INFLUENCING FACTORS IN LUMINESCENCE DATING
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摘要: 释光测年中影响环境剂量率（D）的主要因素包括含水量、宇宙射线、a值（α辐射相对于γ辐射产生释光的效率）和氡逃逸等。为研究这些影响因素对D值的影响程度，采用不同的参数值对一个假定U、Th和K含量已知的样品进行了较详细的定量计算。研究结果表明，含水量变化对环境剂量率影响最大，影响程度甚至可达50%以上；其次为宇宙射线的影响，最大可达近15%；氡逃逸的影响最多不超过8%；而a值通常取固定值，产生的影响则相对小的多。Abstract: The environmental dose rate (D) in luminescence dating can be influenced by water content, cosmic ray, factor a, radon escape, etc. A series of detailed quantitative calculations were applied to the sample A1 with given U, Th and K content for D values using different parameter values of water content, cosmic rays, factor a. The calculations show that the greatest influence is up to 50% with the changes of water content, and the influence from cosmic rays is up to 15%. The influence from factor a is relatively smaller because it usually is a given constant value. The radon escape will bring an error no more than 8%.
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图 1 宇宙射线剂量率校正时地磁纬度与校正系数（F、J和H）的关系[5]
Figure 1. Relationship between geomagnetic latitudes and correction coefficients (F, J, H)
图 2 北纬15°、35°、55°，东经105°处不同海拔的地表Dc值
Figure 2. The surface Dc at 105°E, different latitudes and altitudes
图 3 北纬35°、东经105°处不同海拔不同样品埋深时的Dc值
Figure 3. The Dc on different depths and different altitudes at 105°E and 35°N
图 4 不同Fw值、不同含水量时样品A1的D值
Figure 4. The D under different water contents and different Fw values for sample A1
表 2 样品A1环境剂量率计算参数
Table 2. Parameters for the calculation of environmental dose rate of sample A1
表 3 样品A1环境剂量率计算结果
Table 3. Results of environmental dose rate for sample A1
表 4 不同经度、纬度时的地磁纬度值
Table 4. The geomagnetic latitude at different longitude and latitude
表 5 北纬15°线不同海拔不同埋深时的Dc值
Table 5. The Dc under different altitudes and depths at 15°N
表 6 北纬35°线不同海拔不同埋深时的Dc值
Table 6. The Dc under different altitudes and depths at 35°N
表 7 北纬55°线不同海拔不同埋深时的Dc值
Table 7. The Dc under different altitudes and depths at 55°N
表 8 不同Fw值、不同含水量时样品A1的D值
Table 8. The D under different water content and different Fw for sample A1
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