Construction of Novel Reflectometer with Pulsed Thermal Neutron for Free Surface and Nanostructural Analysis of Polymer Surfaces and Interfaces

一种用于研究自由表面的新型垂直散射面中子反射计（Advanced reflectometer for Interface and Surface Analysis，ARISA）安装在KENS的一个观察常温水慢化器的热中子口上，ARISA是一种独特的在脉冲中子源上使用热中子的反射计，也是日本第一台垂直散射面中子反射计。安装了一个带有两个束流孔的内部铁准直器和一个中子束线屏蔽，以尽量减少由于束流孔本身产生的屏蔽损失而直接来自中子靶的高能中子。内准直器形成两个独立的向下的束流孔，两个束流孔的角度不同，分别为0-0.47度和1.4度。中子束线屏蔽还具有附加束流快门的功能。在0.07- 0.4nm波长范围内，液体和固体样品在垂直方向上的中子动量转移覆盖范围的设计规格分别为0.008-0.61 μ m<-1>和0.008-2.8 μ m<-1>。制备了一个液体槽和一个高温池作为样品环境装置。已经开始使用镍膜和一些聚合物系统进行性能测试。

A new neutron reflectometer (Advanced reflectometer for Interface and Surface Analysis, ARISA) with vertical scattering-plane geometry for studying free surface was installed at a thermal neutron port viewing an ambient-temperature water moderator at KENS.ARISA is a unique reflectometer using thermal neutrons at a pulsed spallation neutron source as well as the first neutron reflectometer with vertical scattering-plane geometry in Japan. An inner iron collimator with two beam holes and a neutron beam-line shield were installed to minimize high-energy neutrons directly coming from the neutron-target due to the shield loss produced by beam holes themselves. The inner collimator makes two independent downward beam holes with different angles, 0-0.47 degree and 1.4 degree. The neutron beam-line shield has function of an additional beam-shutter as well. The designed specifications for the covered range of neutron momentum transfer in the vertical direction are 0.008-0.61 Å^<-1> and 0.008-2.8 Å^<-1> for liquid and solid samples, respectively, using neutrons within wavelength range of 0.07-0.4 nm. A liquid trough and a high-temperature cells were prepared as sample environment equipments. The performance tests have been started using nickel films and a few polymer systems.