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

粒子放射治疗是治疗多种癌症最有效的方法之一，由于它为治疗严重的癌症提供了很高的可能性，而且可以有效地抑制副作用，因此需要开发一种基于准确的辐射剂量估计的高级治疗计划方法。核碎片在破坏DNA过程中起着关键作用，因此核数据是实现剂量估算系统的重要信息量。由于这些数据具有很高的线性能量传递，在测量这些数据时存在困难，因此有必要开发一种新的检测系统。因此，我们开发了一套闪烁体探测器系统，并将其应用于HIMAC，NIRS的核数据测量。为测量更多碎片的核素付出了大量努力。实验在HIMAC，NIRS进行。同步加速器HIMAC提供高能C-12离子束，轰击C-12目标。用气体闪烁探测器探测反应产生的带电粒子。最后，我们确定了质子产生双微分截面在最大的前角0到3度，这是非常困难的测量一般。测量的质子能量范围从200 MeV到500 MeV。此外，我们还进行了几次测量以进行探测器测试，以便进行能量校准。其中一项是测量晶体对质子和其他粒子的响应，这是在俄罗斯JINR进行的。这些数据显示了一个重要的建议，即Birks治疗的极限，进一步的分析应该基于Mayer-Murray万能曲线方法。需要进一步的微观方法才能更深入地理解。

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.