Helical Instability Evolution in Dynamic-Screw-Pinch-Driven Plasma Implosions

该奖项支持了一项名为动态螺旋夹紧的等离子体压缩技术的研究，该技术已被证明可以减少等离子体的不稳定性。在这个项目中获得的知识可以使更强大的x射线产生，高压材料特性实验，更有效的核聚变产生，以及更好地理解天体物理过程。该项目将通过推进基础科学知识、实现未来能源和提高国防能力来造福社会。该项目还将帮助培养等离子体科学与工程领域的本科生和研究生，同时在学术界、工业界和国家实验室之间建立更牢固的伙伴关系。该项目由美国国家科学基金会物理部授予，并得到能源部国家核安全管理局的支持。这个项目将研究圆柱形等离子体在被磁场强烈压缩时变得不稳定和分裂的方式。最近，一种被称为动态螺旋夹紧（DSP）的等离子体压缩技术已经被证明可以减少在1毫安，100纳秒脉冲电力设施上初始固体金属薄箔衬里内爆中等离子体不稳定性的增长。DSP技术使用具有时变俯仰角的螺旋磁场来压缩圆柱形等离子体。尽管DSP技术取得了成功，但相对于纯方位磁场的标准z-pinch驱动的不稳定性，DSP驱动的不稳定性最初是如何形成和演变的问题仍然存在。这个项目将通过计算和实验来评估相互竞争的理论。具体而言，本项目将研究电热不稳定性、日冕等离子体动力学和磁场俯俯角在磁瑞利-泰勒不稳定性（MRTI）的产生和演化中的作用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award supports an effort to understand a plasma compression technique called the dynamic screw pinch, which has been demonstrated to reduce plasma instabilities. The knowledge gained in this project could enable more powerful x-ray generation, higher-pressure materials properties experiments, more efficient nuclear fusion generation, and a better understanding of astrophysical processes. The project will benefit society by advancing basic scientific knowledge, enabling future energy sources, and improving national defense capabilities. This project will also help train a diverse group of undergraduate and graduate students in plasma science and engineering while building stronger partnerships between academia, industry, and national laboratories. The project is awarded by the NSF Division of Physics with support from the National Nuclear Security Administration within the Department of Energy. This project will investigate the way in which cylindrical plasmas become unstable and break apart when they are strongly compressed by a magnetic field. Recently, a plasma compression technique called the dynamic screw pinch (DSP) has been demonstrated to reduce plasma instability growth in initially solid-metal thin-foil liner implosions on 1-MA, 100-nanosecond pulsed power facilities. The DSP technique uses a helical magnetic field with a time-dependent pitch angle to compress the cylindrical plasma. Despite the success of the DSP technique, questions remain as to how DSP-driven instabilities initially form and evolve relative to those driven by a standard z-pinch with a purely azimuthal magnetic field. This project will evaluate competing theories computationally and experimentally. Specifically, this project will investigate the roles of the electrothermal instability, coronal plasma dynamics, and magnetic field pitch angles in the seeding and evolution of the magneto-Rayleigh-Taylor instability (MRTI).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.