Gur D, Bukovitz A G, Serago C
Med Phys. 1979 Mar-Apr;6(2):145-6. doi: 10.1118/1.594525.
The amount of x-ray contamination near the surface of a phantom irradiated with electron beams was measured directly. Measurements were done to ascertain if photon contamination in the beam contributes a higher dose to the more superficial layers of an irradiated medium than indicated by conventional methods. A 1.4-kG magnetic field was used to deflect the electron beams generated by a Philips SL/75-20 linear accelerator. The electron energies studied were 8, 10, 12, 14, 17, and 20 Mev. After sweeping the electron beam, a significant amount of photon contamination was measured in all cases. The characteristic qualities of the photon contamination were measured directly in a water tank. They were found to agree with those of bremsstrahlung spectra generated in a thin target with a virtual source at the location of the scattering foil.
直接测量了用电子束照射的体模表面附近的X射线污染量。进行测量以确定束流中的光子污染是否会给被照射介质的较浅层带来比传统方法所表明的更高剂量。使用1.4千高斯的磁场使飞利浦SL/75 - 20直线加速器产生的电子束发生偏转。所研究的电子能量为8、10、12、14、17和20兆电子伏。在扫描电子束之后，在所有情况下都测量到了大量的光子污染。在水箱中直接测量了光子污染的特征性质。发现它们与在散射箔位置具有虚拟源的薄靶中产生的韧致辐射光谱的特征性质相符。
