CAREER: Kinetic Theory of Irreversible Processes

该奖项的部分资金来自2021年美国救援计划法案（公法117-2）。该职业奖支持将理论，数值模拟和航天器数据分析结合在一起，以促进我们对基本等离子体过程的理解。等离子体是由带电粒子组成的气体，它们在我们的宇宙中随处可见。氖光、闪电、极光、恒星和行星际空间都是等离子体状态物质的例子。电磁相互作用在等离子体动力学中起着至关重要的作用，包括等离子体的加热和加热。例如，这种相互作用是导致太阳外层大气，太阳日冕，温度超过一百万度的原因。太阳不断向行星际空间发射的等离子体风，即太阳风，也被加热到比当前理论预测的温度更高的温度。 等离子体物理学中的一个悬而未决的问题是，储存在电场和磁场中的能量如何最终加热等离子体。 在该奖项的支持下，将通过开发尖端的数值工具，辅以理论和对过去和当前空间任务数据的分析来研究这一问题。这项研究将与一项增强的空间物理教育计划相结合，该计划将针对各级教育中STEM学科中代表性不足的少数群体。通过夏令营和展示课程，将组织引人入胜的活动，以提高学生对空间物理及其对生活和技术影响的认识。该奖项建立了一个研究计划，解决动力学效应和湍流系统（如日光层的天然等离子体）大尺度动力学之间的相互作用。在自然界和实验室中遇到的大多数等离子体环境可以被分类为弱碰撞或无碰撞，在这个意义上，与碰撞弛豫相关的时间尺度比典型的动力学时间尺度长几个数量级。因此，等离子体通常远离热力学平衡，基于这种状态的弱扰动的传输模型不适用。相反，动力学机制，如波粒相互作用在能量耗散和等离子体放电过程中起着至关重要的作用。 该奖项支持的研究工作旨在了解动力学物理和大尺度动力学之间的双向反馈，以推进对弱碰撞磁化等离子体中湍流级联，耗散和粒子扩散过程的了解。为此，一个扩展的混合碰撞动力学模型将开发和使用的调查，第一次，弱碰撞磁化等离子体中的湍流。 将对过去和当前空间飞行任务的现场航天器数据分析进行分析，并与数值和理论结果进行比较。这项工作的结果将在日光层环境中得到应用，但也将在更奇异的天体物理系统中得到应用，如恒星风和脉冲星风，围绕不同中心物体的吸积盘，以及星际介质。该奖项反映了NSF的法定使命，并被认为值得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来支持。

This award is funded in part under the American Rescue Plan Act of 2021 (Public Law 117-2). This CAREER award supports bringing together theory, numerical simulations and spacecraft data analysis to advance our understanding of fundamental plasma processes. Plasmas are gases made of electrically charged particles, and they can be found everywhere in our universe. Neon lights, lightning, auroras, stars and the interplanetary space are all examples of matter in the plasma state. Electromagnetic interactions play a crucial role in the dynamics of plasmas, including plasma energization and heating. For example, such interactions are responsible for heating the outer solar atmosphere, the solar corona, to temperatures in excess of one million degrees. The wind of plasma continuously emitted by the sun into the interplanetary space, the solar wind, is also heated to temperatures higher than what current theories predict. One of the open questions in plasma physics is how the energy stored in the electric and magnetic fields can ultimately heat a plasma. This problem will be investigated with the support of this award by developing cutting-edge numerical tools complemented by theory and analysis of data from past and current space missions. The research will be integrated with an enhanced space physics education plan that will target underrepresented minority groups in STEM disciplines at all levels of education. Engaging activities will be organized through summer camps and showcase lessons to enhance student awareness about space physics and its impacts on life and technology.This award establishes a research program that addresses the interplay between kinetic effects and the dynamics on the large scales in turbulent systems such as the natural plasmas of the heliosphere. Most of the plasma environments encountered in nature and in the laboratory may be classified as weakly collisional or collisionless, in the sense that the timescales associated with collisional relaxation are orders of magnitude longer than the typical dynamical ones. As a consequence, plasmas are most often far from thermodynamic equilibrium, and transport models based on weak perturbations from such states do not apply. Instead, kinetic mechanisms such as wave particle interactions play a crucial role in the processes of energy dissipation and plasma energization. The research effort supported with this award aims to understand the two-way feedback between kinetic physics and large-scale dynamics to advance knowledge of the processes that govern the turbulent cascade, dissipation and particle energization in weakly collisional magnetized plasmas. To this end, an extended hybrid collisional kinetic model will be developed and used to investigate, for the first time, turbulence in weakly collisional magnetized plasmas. In-situ spacecraft data analysis from past and current space missions will be analyzed and compared with numerical and theoretical results. Results from this work will find application in heliospheric environments, but also in more exotic astrophysical systems such as stellar and pulsar winds, accretion disks around widely different central objects, and the interstellar medium.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.