Beach J L, Kelsey C A
Phys Med Biol. 1975 Jan;20(1):47-53. doi: 10.1088/0031-9155/20/1/004.
This paper presents an evaluation of a continuously variable collimator for 14 MeV neutrons. Beam profiles measured in air and a phantom are used to demonstrate the relative importance of patient scatter and collimator throat scatter as they limit the performance characteristics of the collimator. The collimator consists basically of two sets of jaws each composed of 30 cm of steel followed by 20 cm of polyethylene. A solution is presented for the asymmetry in vertical and horizontal collimating characteristics resulting from the use of thick collimators. Beam profiles obtained with the collimator are comparable to published values for a fixed field 14 MeV neutron collimator.
本文介绍了一种用于14兆电子伏中子的连续可变准直器的评估。在空气中和模体中测量的射束轮廓用于证明患者散射和准直器喉部散射在限制准直器性能特征时的相对重要性。该准直器基本上由两组夹爪组成，每组夹爪由30厘米厚的钢和其后20厘米厚的聚乙烯组成。针对使用厚准直器导致的垂直和水平准直特性不对称问题提出了一种解决方案。使用该准直器获得的射束轮廓与已发表的固定野14兆电子伏中子准直器的值相当。
