Development of a gas-scintillator detector and measurements of medical nuclear data at HIMAC

微粒放射治疗是多种癌症最有效的治疗方法之一，因为它有很高的治愈可能性和高生活质量的严重癌症，为了有效地抑制副作用，需要开发一种基于准确估计辐射剂量的晚期治疗计划方法。核碎片在破坏DNA中起着关键作用，因此核数据是实现剂量估算系统的重要数据。由于测量这些具有很高线性能量传递的数据存在困难，因此有必要开发一种新的探测器系统。为此，我们研制了一种闪烁体探测系统，并将其应用于近红外光谱仪的核数据测量。为了测量更多的碎片核素，人们付出了巨大的努力。实验在HIMAC， NIRS进行。同步加速器HIMAC提供高能C-12离子束，轰击一个C-12目标。用气体闪烁探测器探测反应发射的带电粒子。最后，我们确定了质子生产的双微分截面，在大多数正向角0到3度，测量通常是非常困难的。所测质子的能量范围为200 - 500兆电子伏。此外，我们还为探测器测试进行了几次测量，以便进行能量校准。其中一个是测量晶体对质子和其他粒子的响应，这是在俄罗斯JINR完成的。数据显示了一个重要的建议，即Birks治疗的局限性，进一步的分析应基于Mayer-Murray通用曲线方法。为了更深入的理解，需要进一步的微观方法。

Particulate radiation therapy is one of the most effective treatments for variety of cancers, because it offers a high possibility to cure serious cancer with high QOL To suppress side effects effectively, it is required to develop a method of advanced treatment planning based on accurate estimate of radiation dose. Nuclear fragments play a key role in destructing DNA, hence nuclear data are important quantity to realize the dose estimation system. Since there are difficulties in measuring these data, which have a very high linear energy transfers, it is necessary to develop a new detector system. Therefore, we developed a scintillator detector system and applied it to nuclear data measurements at HIMAC, NIRS. Extensive efforts were devoted to measure more nuclides of fragments.Experiments were carried out at HIMAC, NIRS. The synchrotron HIMAC provided high-energy C-12 ion beams, which bombarded a C-12 target. Emitted charged particles from reactions were detected with the gas-scintillation detector. Finally, we determined proton production double-differential cross sections at most forward angles zero to three degrees where measurements are very difficult in general. The energy range of measured protons was from 200 to 500 MeV.In addition, we carried out several measurements for detector test to allow energy calibrations. One was the measurements of crystal response to protons and other particles, which was made at JINR, Russia. The data show an important suggestion that the limit of the Birks treatment, and further analyses should be based on the Mayer-Murray universal curve approach. Further microscopic approach would be needed for deeper understanding.