FTO客体3m闪光照相的Monte Carlo研究

 研究了客体模型FTO的闪光照相系统X光输运过程，给出了直穿照射量、散射照射量、直散比、直穿照射量能谱、散射照射量能谱、直穿X光通量能谱和散射X光通量能谱在记录平面的空间分布。结果表明：后锥是照射量散射成分的主要来源，后锥照射量占总散射量97%；后锥也是造成散射的空间分布不均匀的主要器件，这一不均匀性高达58%。照相系统的最小直散比非常小，表明锥造成的散射已经严重地淹没了直穿（轫致辐射）信号。计算中使用高空间分辨率记录法进行分点，合成图像对吸收系数的复原结果与国外报道的结果相符。

Monte-Carlo Research of Flash Radiograph about FTO at 3 m to the target

The X-ray transport of flash radiograph about FTO(French test object)was studied. Within the recording plane at 3m, the direct and scattering exposures, the direct-scattering ratio, the spatial spectrum distributions of direct and scattering exposure and flux are respectively given by means of Monte-Carlo simulation. It can be concluded from these results that the back cone, from which 97% scattering exposure comes, is the primary scattering source and the key component which makes the spatial distribution of scattering exposure nonuniformity 58%. The minimum direct-scattering ratio of the radiograph system is so small that the direct exposure can be ignored in comparison with the scattering exposure. The record method with high resolution is used during the simulation, and the reconstruction of attenuation coefficients from the generated image are consist with that of the related reports from other countries.