为满足对中子散射谱仪关键部件的检测需求, 提出一种基于反应堆中子源的中子标准测试束平台概念设计思路。该平台具有测试束流波长(0.1~0.3 nm)连续可调、n/γ可同步分析、样品台可多自由度移动以及便于后续拓展集成等优点。利用蒙特卡罗程序VITESS对平台整体结构, 具体包括聚焦单色器、soller准直器等展开模拟优化分析。该装置利用可拆卸的准直器1实现高通量和较高分辨两种工作模式:工作于高通量模式时, 样品台处中子(波长0.1 nm)束流强度最高可达6.15×106 n/(cm2·s), 水平发散度1°;工作于较高分辨模式时, 分辨率可达0.2％。

To satisfy the progressive requirements of test, a neutron standard test beam based on the reactor neutron source China Mianyang Research Reactor(CMRR) was proposed, and its conceptual design is shown in the paper. This instrument would be used to test the performance of components designed for spectrometer and develop some quantitative analysis of special materials. At first, it was simulated by VITESS software. Then some adjustment about its physical parameter was optimized based on the simulation results. In this system, the monochoromator was designed with vertical focusing function which could provide neutrons with continuous wavelength (0.1-0.3 nm). Between the monitor and the slit, the collimator was removable. While it is removed, the neutron flux at sample stage was up to 6.15×106 n/(cm2·s). With the collimater, the neutron flux at sample stage was reduced to 2.07×106 n/(cm2·s), but the resolution of NSTB was up to 0.2%.