Complex Plasma under Microgravity: Utilizing the International Space Station Plasma Krystal-4 Facility and Beyond

该奖项将支持国际空间站（ISS）上的数据分析和一系列专门实验，旨在了解复杂等离子体系统的基本特性。 等离子体长期以来一直在天体物理学背景下进行研究，因为宇宙的大部分都处于等离子体状态，并且在解释恒星的生命周期方面很重要。等离子体生产方法在半导体工业中的大量使用也证明了基于等离子体的生产方法在我们社会中的经济重要性。在几乎所有存在等离子体的情况下，小颗粒可能作为天然成分嵌入等离子体环境中，作为化学反应的非预期生长的结果，或故意引入。尘埃粒子成分的存在可以显著改变等离子体的整体行为和性质。在某些情况下，灰尘的存在可能具有负面影响，例如在处理等离子体制造中的产量显著降低或在聚变装置的设计中的不期望的复杂性。另一方面，尘埃的存在也可以导致新的等离子体产生方法，并提供了一个可访问的，优秀的模型系统来研究一般复杂粒子系统的普遍行为和性质。复杂等离子体研究的全部潜力要求在国际空间站提供的减少重力影响的情况下进行一些实验。该奖项将通过提供与国际合作者团队合作的机会来支持下一代高素质科学家和工程师的培训，调查人员将利用最近开发的微重力复合（尘埃）等离子体设施Plasma Krystal-4（PK-4），这是目前在国际空间站上的欧洲-俄罗斯设备。美国团队将与欧洲PK-4科学家核心团队密切合作，研究复杂等离子体的基本方面，包括单个粒子的充电和相互作用，粒子传输和整个系统的热特性。复杂等离子体中粒子之间的这些基本相互作用是理解其整体行为的基础。例如，相对于随机运动增加相互作用的强度可以使系统经历从不规则的、不相关的（液体）状态到有序的晶体结构（固体）的转变。将利用PK-4实验获得的实验数据，通过检查粒子对碰撞过程中单个粒子的动力学，研究带电和粒子对相互作用。将利用从PK-4实验中获得的额外实验数据和专门的地面实验的结果来检查粒子的传输和加热。将开发跟踪单个粒子运动（粒子跟踪测速仪）和整体粒子流（粒子图像测速仪）所需的软件工具。还将进行一系列实验，以支持开发未来可能的微重力复杂等离子体实验。 这项支持本科生的奖项是根据“美国宇航局/美国国家科学基金会关于尘埃等离子体科学的合作伙伴关系：利用国际空间站上的PK-4设施”颁发的，是对美国宇航局根据联合方案颁发的奖项的补充。

This award will support the analysis of data and a series of dedicated experiments on the International Space Station (ISS) aimed at understanding fundamental properties of the complex plasma systems. Plasmas have long been studied in the astrophysical setting since most of the universe is in a plasma state and are important in explaining the live cycles of stars. The heavy use of plasma production methods in the semiconductor industry also demonstrates the economic importance of plasma based production methods in our society. In nearly all situations were plasmas exist, small particles may be embedded in the plasma environment either as a natural component, as a result of unintended growth from chemical reactions, or introduced intentionally. The presence of the dust particle component can significantly change the overall behavior and the properties of the plasma. In some cases, the presence of the dust can have negative effects such as significant yield reductions in processing plasma manufacturing or undesired complications in the design of fusion devices. On the other hand, the presence of the dust can also result in new plasma production methods and provides an accessible, excellent model system to investigate the universal behavior and properties of general complex particle systems. The full potential of the complex plasma research requires that some experiments be performed under reduced gravitational influence, as provided by the ISS. This award will support the training of the next generation of highly qualified scientists and engineers by providing the opportunity to work with a team of international collaborators.The investigators will make use of the recently developed microgravity complex (dusty-) plasma facility Plasma Krystal-4 (PK-4), which is a European-Russian apparatus now on the International Space Station. Working in a close collaboration with the European core team of PK-4 scientists, the US team will study fundamental aspects of complex plasma including the charging and interaction of individual particles, particle transport and the thermal properties of the overall system. These fundamental interactions between the particles in a complex plasma is the basis for understanding its overall behavior. For example, increasing the strength of the interaction relative to the random motion can cause the system to undergo a transition from an irregular, uncorrelated (liquid) state to an ordered, crystalline structure (solid). Using experimental data obtained from the PK-4 experiment, the charging and particle pair interaction will be studied by examining the dynamics of individual particles during pair collisions. Particle transport and heating of particles will be examined using additional experimental data obtained from the PK-4 experiment and results from dedicated ground based experiments. Required software tools to follow the motion of individual particles (particle tracking velocimetry) and the overall particle flow (particle image velocimetry) will be developed. A series of experiments to support the development of potential future microgravity complex plasma experiments will also be performed. This award to support an undergraduate student is made under a "NASA/NSF Partnership on Science of Dusty Plasmas: Utilizing the PK-4 Facility on board the International Space Station" and is complementary to a NASA award made under the joint program.