Experimental Comparison of Performances of Ultracold Neutron Gravity Spectrometers

本研究的目的是对两台超冷中子重能仪的性能进行实验比较，一台是目前在朗格万研究所使用的中子到达聚焦原理的超冷中子重能仪，另一台是本申请人小组研制的使用散射中子下落聚焦原理的改进版本。作为本次国际合作实验比较的第一步，首席研究员访问了美国罗德岛大学，与发明并完成了NESSIE超冷重力仪的Albert Steyerl教授进行了讨论，并获得了关于超低温中子重力仪的极高能量分辨率、中子的聚焦特性和散射样品的几个条件等许多有指导意义的指示。我们之间也达成了一致，我们的性能比较实验应该在朗格万研究所的超冷中子装置上进行。接下来，T. Ebisawa先生访问了lae Langevin研究所，并与负责这些超冷中子设施的W. Drexel博士积极讨论了NESSIE工作条件的进一步细节。通过这些研究，得出了几个重要的结论和注意事项，特别是散射样品和重力光谱仪实验的相关条件。此外，Y. Kawabata博士还访问了Laue Langevin研究所和我们的新重力光谱仪（Drexel博士命名为SUPERNESSIE）的实验地点，进行了一些初步准备工作，以进行性能测试和演示。目前放置在指定位置的重力绕射仪已进入实验研究的最后阶段，根据我们的研究计划，将在不久的将来将其替换为我们的监测仪。少

The purpose of the present research is to carry out the experimental comparison of the performances of two ultracold neutron gravity spectrometers, one is now working at the Institut Laue Langevin with the principle of reach focusing of neutrons, and the other is the improved version developed by the group of the present applicant with the principle of the fall focusing of scattered neutrons.As the first step of the present international collaboration for the experimental comparison, the head investigator visited the University of Rhode Island to discuss with Prof. Albert Steyerl who invented and completed the reach focusing gravity spectrometer named NESSIE, and obtained much instructive indications concerning the very high energy resolution, focusing properties of neutrons and several conditions on the scattering samples for the gravity spectrometers of ultracold neutrons. The agreement among us was also derived that our experiment for the comparisons of performances should bec arrie … More d out at the ultracold neutron facility of the Institut Laue Langevin.In the next place, further details of the working conditions of NESSIE were investigated by Mr. T. Ebisawa who visited the Institut Laue Langevin and discussed actively with Dr. W. Drexel, the responsible staff on these ultracold neutron facilities. Several important conclusions and precautions werederived through these investigations concerning especially the scattering sample and related conditions for the experiment using the gravity spectrometer.Further, some preliminary preparations were progressed by Dr. Y. Kawabata who also visited the Institut Laue Langevin and the experimental location for our new gravity spectrometer, named SUPERNESSIE by Dr. Drexel, to carry out performance tests and demonstrations was assigned. The gravity diffractometer which occupying now the location assigned is in the course of the final stage of the experimental research and therefore it will be replaced to our supernessie in near future according to our research program. Less