Muntz E P, Fewell T, Jennings R, Bernstein H
Med Phys. 1983 Nov-Dec;10(6):819-23. doi: 10.1118/1.595360.
We have studied the angular distribution of scattered radiation at low energies for angles between 2 degrees and 15 degrees from the outward normal to the exit surface of several phantoms, with 1 degree resolution. A cryogenically cooled germanium detector was used to measure the spectra of the scattered radiation. The differential scattering fluences, or numbers of photons per unit solid angle per unit surface area, exhibit distinct peaks at angles in the vicinity of 5 degrees, with the angular position being only slightly energy dependent but very material dependent. The scattered spectra show large changes as a function of angle, in some cases actually becoming harder than the exit unscattered beam. The significance of this behavior relative to the imaging of targets in mammography examinations is discussed.
我们研究了几种体模出射表面外法线方向2度至15度之间低能散射辐射的角分布，分辨率为1度。使用低温冷却的锗探测器测量散射辐射的能谱。微分散射注量，即单位立体角单位表面积的光子数，在5度附近的角度处呈现明显的峰值，角位置仅略微依赖于能量，但非常依赖于材料。散射能谱随角度变化显示出很大的变化，在某些情况下实际上比出射的未散射光束更硬。讨论了这种行为相对于乳腺摄影检查中目标成像的意义。
