Compton spectroscopy in the diagnostic X-ray energy range: I. Spectrometer design
Compton spectroscopy in the diagnostic X-ray energy range: I. Spectrometer design
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诊断X射线能量范围内的康普顿光谱：一、光谱仪设计
DOI：
10.1088/0031-9155/34/2/003
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
G A Carlsson
中科院分区：
文献类型：
--
作者：
G Matscheko;G A Carlsson
本文分析了用于临床实验室X射线管光子能谱测量的康普顿谱仪的优化设计。这些要求是：（i）相干散射和多次散射使测量失真，必须避免;（ii）测量时间应尽可能短，以避免对X射线管的不必要磨损;以及（iii）应将由于散射几何形状引起的能量分辨率的损害保持在最小程度。建议散射角为90 °。（低原子序数材料的）长圆形杆（直径0.5-4 mm，长20-40 mm）形状的散射体比散射箔更优选。为了在检测器中建立足够高的计数率，与使用大的检测器区域（>或=4 mm直径）相比，优选使用短的焦点-散射体距离（大约200 mm）。短焦距和90'散射角是测量CT机机架中可用空间有限的能谱的优势。为了将几何能量展宽限制为小于1 keV，对于100-150 keV的入射光子能量，记录光子的散射角的扩展必须不超过1-2“。
The optimal design of a Compton spectrometer for measuring photon energy spectra from X-ray tubes in a clinical laboratory is analysed. The demands are: (i) coherent and multiple scattering distort the measurements and must be avoided; (ii) the measuring time should be as short as possible to avoid unnecessary wear on the X-ray tube; and (iii) the impairment in energy resolution due to the scattering geometry should be kept minimal. A scattering angle of 90' is advocated. Scatterers (of low-atomic-number material) in the shape of long circular rods (0.5-4 mm diameter, 20-40 mm long) are preferable to scattering foils. Use of a short focus-scatterer distance ( approximately 200 mm) is to be preferred compared to using a large detector are a (>or=4 mm diameter) in order to establish a sufficiently high count rate in the detector. Short focal distances and a 90' scattering angle are advantages in measuring energy spectra in the gantry of CT machines where the available space is limited. To limit the geometrical energy broadening to less than 1 keV, the spread in scattering angles of registered photons must not exceed 1-2' for incident photon energies of 100-150 keV.