Preparation and Applications of Neutron Storage Bottle with Ultrafine Polished Metal Mirrors

1.为研究中子衰变的物理性质，设计并优化了超冷中子贮存瓶。研制了衰变粒子谱仪，并对其特性进行了分析。这些研究结果发表在j.p hysl . soc上。日本,Suppl.A.2。为了制备中子衰变实验用的最佳储存瓶，对金刚石表面加工和电化学表面抛光这两种金属表面处理技术进行了研究。因此，金刚石表面加工保留了工作模式的表面结构，不适用于不锈钢等硬材料，而电化学表面抛光适用于大表面积硬材料的超高精度抛光。这些发展已在1996年KURRI进展报告和研究反应堆研究所的科学会议中报告。提出了一种新的关于瓶镜全反射理论表达的重要方法，该方法在KURRI-KR-14（1997）中有报道。根据这些研究进展，采用电化学超高处理法制备了高质量的不锈钢镜面。反射率研究的测量结果提供了电光和化学抛光工艺最佳组合的信息。这些研究的结果发表在出版物《Hamon》7（1997）上。在此基础上，对衰变瓶的中子储存性能进行了数值分析，并制备了直径50 cm、长度60 cm、圆柱形、切向注入的不锈钢衰变瓶。在筑波KEK举行的JHP'98研讨会上介绍了这些瓶子安排的发展。所制备的瓶与KUR超镜中子透平装置连接，用于瓶的特性研究和进一步应用于中子物理实验。

1.An ultracold neutron storage bottle was designed with optimization for the studies on physical propeties of neutron beta decay. A decay particle spectrometer was developed and the characteristics were clarified. These results were published in J.Phys.Soc.Japan, Suppl.A.2.In order to prepare the best storage bottle for neutron decay experiments, the highest technologies of metal surface treatments were studied on thediamond surface working and the electro-chemical surface polishing.3.As the results, the diamond surface working remains surface structure of working patters and not applicable to hard materials such as stainless steel, while the electro-chemical surface polishing is applicable to ultra-high precision polishing on a large surface area of hard materials. These developments were reported in KURRI Progress Report 1996 and the Scientific Meeting in the Research Reactor Institute.4.A new important approach was developed on the theoretical expression of the total reflection of bottle mirrors, and the approach was reported in KURRI-KR-14(1997).5.According to these research developments, high quality stainless steel mirrors were prepared by the electro-chemical ultra-high treatments. The meaured results of the reflectivity studies gave informations on the best combination of the electic and chemical polishing processe. The results of these studies were reported on a publication "Hamon" 7(1997).6.Based on the results of these studies, numerical analyzes on the neutron storage properties of decay bottles were carried out, and a cylindrical shape, tangential injection, 50 cm diameter and 60 cm lenght stainless steel bottle was prepared. The developments of these bottle arrangements were presented in the Workshop JHP'98 held at KEK,Tsukuba.7.The bottle prepared was connected to KUR supermirror neutron turbine facility for the experiments of bottle characteristics studies and further applications to neutron physics experiments.