Development of Bending Proton Beam Radiography

研制了高灵敏度、高分辨率的实时质子照相系统。当使用不透明流体作为工作流体时，测试截面由金属制成，不能使用光学方法来显示沸腾的气泡。由于高速事件，如沸腾气泡的行为，它已经很难用X射线或中子束可视化。在这些情况下，可以预期质子照相是有用。因为质子射线照相是依赖于质子的电离功率在其射程末端附近的距离快速变化，并与高通量的质子束流一起使用。利用弯曲质子束照相技术，对弯曲毛细管道构成的平板热管内沸腾气泡等动态事件进行了可视化研究。所用质子束照相方向与重力方向垂直或平行，使用13He单色质子束。在平板加热器上用质子注量率为10~(-11)粒子/cm~(-2)a的质子束照射实验区，然后在测试区附近的荧光屏上拍摄沸腾气泡的质子照相。用高速摄像机拍摄的气泡图像。

High sensitive and high resolution real-time proton radiography system has been developed. When an opaque fluid is used as a working fluid and the test section is made of metal, optical method cannot be used for the visualization of the boiling bubbles. It has been difficult to visualize with X-ray or neutron beams because of the high speed events such as behaviors of boiling bubbles. In these case, it may be expected that proton radiography is useful. Because proton radiography is depends on the rapid change of ionizing power of proton with distance near the end of their range and is used with a high flux of proton beams. In the study, the visualization of the dynamic events such as boiling bubbles in a flat plate heat pipe made of many turns of meandering capillaries tunnel was investigated by using bending proton beam radiography. The direction of the applied proton beam radiography was either perpendicular or parallel to the direction of gravity.The monochromatic proton beam of 13 Hey was used. Test section were irradiated with proton beam flux of about 10^<11> particles/cm^2.a on a flat plat heater and then proton radiography of boiling bubbles were taken on the fluorescent screen near by the test section. Images of bubbles recorded with the high speed video camera.