An advanced neutron beam collimation system has been developed as part of an effort to optimize neutron beam transport at the Weapons Neutron Research (WNR) Facility [1], located within the Los Alamos Neutron Science Center (LANSCE). The goal of this work was to develop and demonstrate techniques to tailor neutron delivery in order to provide maximum available flux on sample with a specific beam profile, while simultaneously reducing unwanted background. A holistic approach was taken, upgrading the facility spallation target, facility metrology infrastructure, and flight path shutter insert to support the implementation of this advanced collimation system. Modern instruments and software were employed to conduct facility surveys, characterization of as-built geometry of critical components, 3D ray tracing and neutron transport calculations. Beam images and flux measurements were acquired after installation to evaluate the performance of the collimation system and to demonstrate consistent agreement with MCNP simulations which showed an 87% increase of flux on sample while providing suppression of background neutron impingement on the sample frame by 10${}^3$.

作为在位于洛斯阿拉莫斯中子科学中心 (LANSCE) 内的武器中子研究 (WNR) 设施[1]优化中子束传输的努力的一部分，已开发出先进的中子束准直系统 。这项工作的目标是开发和演示定制中子传输的技术，以便在具有特定光束轮廓的样品上提供最大可用通量，同时减少不需要的背景。采取整体方法，升级设施散裂目标、设施计量基础设施和飞行路径快门插入以支持实施这种先进的准直系统。现代仪器和软件被用于进行设施调查、关键部件的竣工几何特征、3D 射线追踪和中子输运计算。安装后获取光束图像和通量测量值，以评估准直系统的性能并证明与 MCNP 模拟一致，MCNP 模拟表明样品上的通量增加了 87%，同时将背景中子撞击到样品架上抑制了 10${}^3$.