Sharma R C, Haridasan T K
Environmental Assessment Division, Bhabha Atomic Research Centre, Mumbai 400 085, India.
Health Phys. 1999 Aug;77(2):196-9. doi: 10.1097/00004032-199908000-00010.
Total linear attenuation coefficients of three tissue equivalent materials differing in their fat contents were experimentally determined for low energy photons in the range 13-51 keV. It is found that their variations with photon energy for each of these materials are describable by two distinct power functions with the validity ranges being (13-23 keV) and (32-51 keV), respectively. Therefore, to adequately represent the variation of total linear attenuation coefficients over the full photon energy range i.e., 13-51 keV, a sum of two power functions is needed. Least squares fitted equations to the entire experimental data are thus included. For muscle, the experimental data show a reasonably good agreement with the theoretically computed values that are available in literature.
实验测定了三种脂肪含量不同的组织等效材料对于能量范围在13 - 51 keV的低能光子的总线性衰减系数。结果发现，这些材料中每种材料的总线性衰减系数随光子能量的变化可以用两个不同的幂函数来描述，其有效范围分别为(13 - 23 keV)和(32 - 51 keV)。因此，为了充分表示总线性衰减系数在整个光子能量范围（即13 - 51 keV）内的变化，需要两个幂函数的和。本文还给出了对全部实验数据进行最小二乘法拟合得到的方程。对于肌肉，实验数据与文献中可获得的理论计算值显示出相当好的一致性。
