标题： 波长分辨中子断层扫描用于晶体材料 显示英文标题

标题： Wavelength-resolved neutron tomography for crystalline materials

摘要： 波长分辨（WR）中子透射断层扫描是一种用于表征工程材料的新兴技术。 虽然非晶样品的断层重建是直接的，但对具有单晶域的样品进行重建却具有挑战性，因为样品的衰减会随着其相对于入射束的方向而变化，这是由于布拉格散射所致。 在本文中，我们提出了一种算法，可以从WR中子断层扫描测量中重建具有单晶域的样品。 特别是，我们使用基于模型的迭代重建（MBIR）技术，通过识别并排除受布拉格散射影响的测量区域来重建体积。 我们将MBIR方法的输出与一个将重建与识别的布拉格散射相匹配的算法结合，以重建对应于被测样品局部晶体学特征的特征。 使用模拟数据，我们展示了我们的算法如何重建具有单晶域的材料，从而为WR中子成像仪器增加了一种强大的新功能。 显示英文摘要

摘要： Wavelength-resolved (WR) neutron transmission tomography is an emerging technique to characterize engineering materials. While tomographic reconstruction for amorphous samples is straightforward, it is challenging to reconstruct samples with single-crystal domains because the attenuation of the sample varies as a function of its orientation with respect to the incident beam due to Bragg scattering. In this paper, we present an algorithm that can reconstruct samples with single-crystal domains from WR neutron tomographic measurements. In particular, we use a model-based iterative reconstruction (MBIR) technique that reconstructs the volume by identifying and leaving out the regions of the measurement that are affected by Bragg scatter. We combine the output of the MBIR method with an algorithm that matches the reconstruction to the identified Bragg scatter to reconstruct a feature that corresponds to the local crystallography of the sample being measured. Using simulated data, we demonstrate how our algorithm can reconstruct materials with single-crystal domains, thereby adding a powerful new capability for WR neutron imaging instruments.