CAREER: Magnetogenesis and Plasma Dynamo Across Cosmic Time

现在，在我们的银河系和星系团中，磁场都是常规测量的。研究人员试图了解这些磁场的起源，重点关注磁场在很长一段时间内的复杂变化。他们解决了这些问题：为什么附近的宇宙在观测水平上被磁化？这些田地是什么时候生产的？更具体地说，是什么材料特性赋予了形成星系的材料生长和维持强磁场的能力？研究人员计划用纸笔进行传统计算，并结合最先进的超级计算机模拟，以更好地了解这些磁场是如何形成的。对原星系和星系间空间磁场强度和结构的预测将为下一代射电望远镜做准备。研究人员计划为女性和代表性不足的群体提供培训和鼓励，以选择天体物理流体动力学或等离子体天体物理学方面的职业。这些目标是为了应对等离子体科学中女性和少数族裔的惊人缺乏，以及美国物理和天文学课程中流体和等离子体教育的相对缺乏。将启动针对这些群体成员的两年一次的暑期学校计划。这些学校的所有材料都将公开提供，并将进行一项研究，追踪这些学校对实地征聘和留用的影响。研究者将从基本原理出发，描述宇宙磁力和发电机在时间上的创造和发展，特别关注原星系和星系团中预先存在的种子磁场的不稳定性、湍流和大规模剪切的放大。研究人员将确定等离子体的材料特性如何影响其生长和维持动态重要磁场的能力。他们将模拟从再电离时代到星系早期的属性随时间的变化。这些系统的低密度和高温使得回答这些问题变得复杂，这就排除了磁流体动力学的描述，并使微物理等离子体过程脱颖而出。他们在发电机方面的开创性工作被用来论证在原星系和星系内星系团介质的早期发展中有一个爆炸性的场增长阶段。他们制定了一项研究计划，通过结合传统的分析技术和最先进的数值工具来调查这种可能性。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。

Magnetic fields are now routinely measured both in our Galaxy and in clusters of galaxies. The investigator seeks to understand the origin of these fields, focusing on the complex changes of the magnetic fields over long periods of time. They address these questions: Why is the nearby Universe magnetized at the observed levels? When were these fields produced? More specifically, what material properties give the galaxy-forming material the ability to grow and sustain strong magnetic fields? The investigator plans traditional, paper and pencil, calculations combined with state-of-the-art supercomputer simulations to better understand how these magnetic fields came to be. Predictions for the strength and structure of magnetic fields in protogalaxies and intergalactic space will be made in preparation for next-generation radio telescopes. The investigator plans to provide women and underrepresented groups the training and encouragement to choose a career in astrophysical fluid dynamics or plasma astrophysics. These goals are in response to the alarming dearth of women and minorities in plasma science and the relative lack of fluid and plasma education in U.S. physics and astronomy curricula. A program of biennial summer schools, targeting members of these groups, will be initiated. All materials from the schools will be made publicly available, and a study will track the impact of these schools on recruitment and retention in the field. The investigator will describe, from first principles, the creation and development of cosmic magnetism and dynamo across time, focusing specifically on the amplification of pre-existing seed magnetic fields in protogalaxies and in clusters of galaxies by instabilities, turbulence, and large-scale shear. The investigator will determine how the material properties of a plasma influence its ability to grow and sustain dynamically important magnetic fields. They will model the properties change with time, from the epoch of re-ionization to the early lives of galaxies. Answering these questions is complicated by the low densities and high temperatures in these systems, which precludes a magneto-hydrodynamic description and brings microphysical plasma processes to the fore. Their pioneering work on the dynamo in this regime is leveraged to argue for a phase of explosive field growth in the early development of protogalaxies and the intra-galactic cluster medium. They formulate a research plan to investigate this possibility by combining traditional analytical techniques with state-of-the-art numerical tools.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.