Neutron Imaging Interferometry for Non-Destructive Testing

干涉测量是一种将波叠加并产生干涉现象的技术，用于提取信息。中子具有粒子和波的双重性质。它们可以被描述为波包，并显示出像X射线和可见光一样的干涉效果。本项目的主要目的是通过模拟和实验来分析和最大化中子干涉波束线性能。研究小组还将建立生物医学应用，包括骨-植入物界面的非侵入性成像，以促进髋关节置换植入物的制造。在这个项目中，PI的目标是建立一个新的综合模拟器，允许中子的散射和相移，适用于现实的中子干涉测量，并得到实验验证。PI和一名研究生将在国家标准与技术研究所(NIST)中子研究中心(NCNR)进行中子干涉成像的模拟和实验。首先，通过将中子描述为粒子和波，建立了一个综合性的中子干涉测量计算机模拟器，并对其进行了验证。其次，为了提高中子干涉层析成像(NIT)的性能，将在模拟中研究特殊的位相光栅。第三，将使用NIT对骨-金属界面进行成像。该项目将在路易斯安那州立大学(LSU)建立一个强中子干涉成像计划。该项目旨在帮助来自多个学科的研究人员(中子成像科学家和无损检测应用专家)，并与路易斯安那州中子散射和路易斯安那州立大学医学物理联合会合作。它将为PI建立一个新的研究计划，并生成将在Github上传播的项目软件。该奖学金和与NIST合作产生的未来项目将培养路易斯安那州立大学的本科生、研究生和博士后。对于X射线干涉测量，存在蒙特卡罗和相干波联合模拟，而对于中子干涉测量则不存在。本项目的主要目的是通过模拟和实验来分析和最大化中子干涉远场成像光束线的性能。研究小组还将建立生物医学应用，如骨-植入物界面的非侵入性体外测试成像，以促进髋关节置换植入物的制造。中子干涉成像的模拟和实验将在美国国家标准与技术研究所(NIST)中子研究中心(NCNR)进行。首先，将建立一个新颖的、全面的计算机模拟器，将中子描述为粒子和波，并进行验证。该模拟器将包括基于蒙特卡罗的中子散射、相干波干涉和振动效应。模拟将使用系统中存在的双相位光栅和从路易斯安那州立大学(LSU)借来的其他高质量中子相位光栅进行实验验证。该模拟器将预测NIST光束线以及橡树岭国家实验室(ORNL)的两条光束线的远场可见度和差分相位对比(DPC)灵敏度。这一目标与路易斯安那州中子散射联合会的目标协同推进了ORNL中子成像和散射研究。其次，将在模拟中研究理想DPC成像的条件。为了提高中子干涉层析成像(NIT)的性能，将对特殊的调制位相光栅(MPG)进行评估。DPC灵敏度将作为一个或多个光栅节距和MPG的空间调制的函数进行研究。第三，将进行新的实验来观察NIT在NIST的体外骨-金属界面。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Interferometry is a family of techniques in which waves are superimposed and cause a phenomenon of interference, which is used to extract information. Neutrons show dual particle and wave nature. They can be described as wave packets and show interference effects like X-rays and visible light. The primary focus of this project is to analyze and maximize the neutron interferometric beamline performances with simulations and experiments. The research team will also establish biomedical applications, which include non-invasive imaging of a bone-implant interface, to facilitate the manufacture of hip replacement implants. Within this project, the PI aims to build a novel comprehensive simulator allowing scatter and phase-shift of neutrons, suitable for realistic neutron interferometry and verified with experiments. The PI and a graduate trainee will perform simulations and experiments on Neutron Interferometry Imaging at the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR). First, a comprehensive computer simulator of neutron interferometry will be built by describing the neutron as a particle and a wave and verified. Second, special phase gratings will be investigated in simulations to improve Neutron Interferometric Tomography (NIT) performance. Third, a bone-metal interface will be imaged using NIT. This project will establish a strong neutron interferometric imaging program at Louisiana State University (LSU). This project seeks to aid researchers from multiple disciplines (neutron imaging scientists and non-destructive testing application specialists) and is synergistic with Louisiana Consortium on Neutron Scattering and LSU Medical Physics. It will establish a new research program for the PI and generate project software that will be disseminated on Github. The future projects generated by this fellowship and collaboration with NIST will train undergraduate students, graduate students, and postdocs at LSU. A combined Monte-Carlo and coherent wave simulation exist for X-ray interferometry but not for neutron interferometry. The primary focus of this project is to analyze and maximize the neutron interferometric far-field imaging beamline performances with simulations and experiments. The research team will also establish biomedical applications such as non-invasive ex-vivo test-imaging of a bone-implant interface, to facilitate the manufacture of hip replacement implants. Simulations and experiments on Neutron Interferometry Imaging will be conducted at the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR). First, a novel, comprehensive computer simulator will be built to describe the neutron as a particle, as well as a wave, and verified. The simulator will include Monte-Carlo based neutron scattering, coherent wave interference, and vibration effects. The simulations will be experimentally verified using dual-phase gratings existing in the system and other high-quality neutron phase gratings that are available on loan from Louisiana State University (LSU). The simulator will predict the far-field visibility and differential phase contrast (DPC) sensitivity at the NIST beamline as well as for two beamlines at Oakridge National Laboratory (ORNL). This objective advances the ORNL neutron imaging and scattering research, in synergy with the goals of the Louisiana Consortium of Neutron Scattering. Second, the conditions for ideal DPC imaging will be investigated in simulations. Special modulated phase gratings (MPG) will be evaluated to improve Neutron Interferometric Tomography (NIT) performance. DPC sensitivity will be investigated as a function of grating pitch or pitches and spatial modulation of MPG. Third, novel experiments will be conducted to observe a bone-metal interface ex-vivo with NIT at NIST.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.