Development of Self-TOF Neutron Detector and Estimation of Neutron Scattering Cross Section

最近，在CYRIC（东北大学）的回旋加速器设施上开发了使用能量范围在20和210 MeV之间的薄Li-y靶轰击质子的准单能中子场，TIARA（JAERI，高崎）和RRC（RIKEN）。在这项工作中，一个自我TOF中子探测器的开发，以测量中子散射截面使用这些中子场。该探测器由闪烁体、辐射体、起始闪烁体和终止闪烁体组成。利用来自两个辐射器的信号的时间差测量了辐射器中反冲质子的飞行时间本文在三个回旋加速器装置上测量了探测器对高能中子的响应特性，分析了探测器的结构和测量条件，这是最好的散射中子测量，进行了研究。测量了65 MeV中子在石墨靶上的散射，得到了30 ° C时65 MeV中子在碳靶上的散射双微分截面。此外，还阐明了使用该探测器还可以测量正向方向的带电粒子产生截面，并获得了C、Al和Cu在0度时的（n，px）和（n，dx）反应截面。

Recently, quasi-monoenoergetic neutron fields using thin Li-y target bombarded proton in an energy range between 20 and 210 MeV were developed at cyclotron facilities of CYRIC(Tohoku Univ.), TIARA(JAERI, Takasaki) and RRC(RIKEN). In this work, a Self-TOF neutron detector was developed to measure the neutron scattering cross sections using these neutron fields. The detector consists of a veto scintillator, a radiator, a start-scintillator and a stop-scintillator. The flight times of the protons recoiled in the radiator are measured using the time difference of the signals from the two scintillators (start and stop), and the injected neutron energy spectra are estimated in the analysis.In this work, characteristics of the detector response to high energy neutrons were measured at the three cyclotron facilities, and detector structure and measurement conditions, which is the best for the scattering neutron measurement, were investigated. The neutrons scattered at graphite target were measured and the double differential cross section (DDX) of scattering for 65 MeV neutron at 30 degree for carbon was obtained. Moreover, it was clarified that the charged particle production cross sections at forward direction could also be measured using the detector, and (n, px) and (n, dx) reaction cross section at 0 degree for C, Al and Cu were obtained.