MRI: Acquisition of a Positron Annihilation Lifetime Spectrometer for Enhanced Materials Characterization

仪器的获取提供了先进的正电子湮没寿命谱的能力，先进的本科生研究和表征材料的空隙结构在（亚）纳米。该设备将填补Austin Peay州立大学材料表征基础设施的关键空白，提供有机，无机和生物物质中无电子密度位点（例如孔隙，空隙，空位和其他缺陷）的重要信息。它将显著促进跨学科教师在生物医学应用材料、电信、能量存储和转换、信息处理和存储、传感器、光子学和光电子学等新兴领域的活动。该仪器将被指定为共享设施，不仅满足内部研究需求，还满足其他学术机构和区域小型企业在材料科学学科的需求。作为美国罕见的设施（与欧洲，中国或日本相比，它经常使用），它具有国际和国内工业-大学合作开发新的先进材料的潜力，促进田纳西州和全国材料科学的进步。参与研究项目的本科生将接触到材料科学和粒子物理学的前沿知识，这将提高他们在劳动力市场和未来努力中的竞争力。他们还将获得在辐射物理学中使用现代实验技术和全球方法的经验。该项目要求获得一个时间分辨率为200 ps（或更高）的皮秒正电子湮没寿命谱（帕尔斯）计时系统、可调探测器组件和快速方便的数据采集系统。帕尔斯将用于研究晶体、玻璃、液体、聚合物和复合材料中的空间不均匀性。它作为结构表征方法的补充技术，能够探测从原子尺度到几十纳米大小的开放和封闭孔，以及电荷分布。特别是，这种技术是有价值的无序材料（如玻璃，陶瓷）的研究，已知的物理性质不仅由它们的原子子系统，但也不可避免地出现作为其合成/制备的非平衡条件的结果的空隙确定。帕尔斯能力将显着提高奥斯汀皮伊州立大学（APSU）正在进行的研究活动，提高性质和质量，以及使新的科学和方向。作为一种尖端仪器，它将用于教育和培训物理学、化学和生物学的本科生，这将提高APSU满足其教育使命的能力。研究人员计划将帕尔斯实现的科学突破纳入本科课程，并将加强他们在田纳西州和全国范围内对K-12学生、工业界、国家实验室和学术界的宣传。拥有这种工具将使APSU成为国内和国际合作更具吸引力的机构，这将使学生交流和REU计划以及联合研究项目成为可能。帕尔斯仪器作为共享设备，也将提高TN领域对空隙结构表征的研究能力。

The instrument acquisition provides state-of-the-art capability of positron annihilation lifetime spectroscopy for advanced undergraduate research and characterization of the materials' void structure at (sub)nanoscale. The equipment will fill in a critical gap in the materials characterization infrastructure at Austin Peay State University, providing a vital information on the electron density-free sites (e.g. pores, voids, vacancies and other defects) in organic, inorganic, and biological substances. It will significantly boost interdisciplinary faculty activity in such emerging areas as materials for biomedical applications, telecommunication, energy storage and conversion, information processing and storage, sensors, photonics, and optoelectronics. The instrument will be designated as a shared facility, serving not only the internal research needs, but also the needs of other academic institutions and regional small businesses working in materials science disciplines. Being a rare facility in USA (compare to Europe, China or Japan, where it is used on a regular basis), it has a potential for international and domestic industry-university partnership to develop new advanced materials, promoting the progress of materials science in Tennessee and across the nation. Undergraduate students participating in the research projects will be exposed to cutting-edge knowledge in materials science and particle physics, which will increase their competitiveness on the labor market and future endeavors. They will also gain an experience of using the modern experimental techniques and worldwide approaches in radiation physics. This proposal requests funds to acquire a picosecond timing system for positron annihilation lifetime spectroscopy (PALS) with 200 ps (or better) time resolution, adjustable detectors assembly, and quick and convenient data acquisition system. PALS will be used for studying the spatial heterogeneities in crystals, glasses, liquids, polymers, and composites. It serves as a complementary technique to structural characterization methods, capable of probing both open and closed pores of sizes ranging from atomic scale to several tens of nanometers, as well as the electric charge distribution. Especially, this technique is valuable for the investigations of disordered materials (e.g. glasses, ceramics), which physical properties are known to be determined not only by their atomic sub-system, but also by voids which inevitably appear as a result of non-equilibrium conditions of their synthesis/preparation. PALS capability will significantly improve the ongoing research activity at Austin Peay State University (APSU), enhance the nature and quality, as well as enable new science and directions. As a cutting-edge instrument, it will be used to educate and train undergraduate students in physics, as well as chemistry and biology, which will increase the APSU ability to satisfy its educational mission. The researchers plan to incorporate scientific breakthroughs made possible by PALS into undergraduate curriculum, and will strengthen their outreach to K-12 students, industry, national labs and academia, in Tennessee and across the nation. Having this instrument will make APSU a more attractive institution for domestic and international collaboration, which will enable students exchange and REU programs, as well as joint research projects. The PALS instrument, as shared facility, will also enhance the capabilities of research in TN area towards void structure characterization.