同步辐射低能X射线的照射量测量与剂量计算

MEASURING EXPOSURE AND CALCULATING DOSE OF THE LOW ENERGY X RAY

用自制自由空气电离室，在能量为２～１２ｋｅＶ同步辐射光束线现场测量了单能Ｘ射线的电离量，依据Ｘ射线在空气中的传输和衰减特性及能量转移系数，计算了电离室入射口的照射剂量值。进而求出在空气中的相应比释动能和光子通量。讨论了软Ｘ射线照射量随能量的分布特性及混合能量Ｘ射线（白光）的照射量测量方法。

To measure exposure of low energy X rays with a free air chamber, the range of X ray energy is from 2 to 12keV. Based on the X ray transmission, attenuation and energy transfer in the air, the X ray exposure at the entrance window of the ionization chamber were calculated. Then both the karma in air and the X ray flux were derived. The change of the X ray exposure with increasing the X ray energy and the measurement of multichromatic (white) X ray exposures were also discussed, respectively.