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Relativistic Nonthermal Particle Acceleration in Kinetic Turbulence and Magnetic Reconnection: Connecting Simulations and Theory

运动湍流和磁重联中的相对论非热粒子加速：连接模拟和理论

基本信息

批准号：
1806084
负责人：
Dmitri Uzdensky
金额：
$ 64.68万
依托单位：
University of Colorado at Boulder
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-01 至 2022-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1806084&HistoricalAwards=false
关键词：
Relativistic Nonthermal Particle Acceleration Kinetic

项目摘要

Highly magnetized plasmas are implicated in accelerating charged particles to very high speeds in astrophysical systems as diverse as pulsar wind nebulae, accretion disk coronae, and relativistic jets. Much recent progress has been numerical, but these large and complex simulations need to be connected to a coherent theoretical picture, which also requires updating theories which predate many of the insights gained from computation. This is exactly what this project will provide, advancing our understanding of acceleration under various physical conditions, extending to space and solar plasmas closer to home, and thus helping to build intellectual bridges between plasma physics, astrophysics, and heliospheric physics. The study includes training, support, and mentoring for a graduate student as well as varied research opportunities for undergraduates. Visually arresting graphics presented through collaboration with the University of Colorado Fiske Planetarium will contribute to the public understanding of modern science.Relativistic charged particles with extended power-law energy distributions are inferred to exist in many astrophysical systems, but the mechanisms for non-thermal particle acceleration (NTPA) are poorly understood. Only recently have first-principles kinetic particle-in-cell (PIC) simulations suggested that reconnection and turbulence in highly magnetized plasmas can efficiently cause relativistic NTPA. The challenge of translating the accumulated numerical results into a coherent theoretical picture is exacerbated by the size and complexity of modern PIC simulations, and the fact that theoretical models predate the simulations and have not been updated. Many theories of NTPA are tied to the Fokker-Planck (FP) equation, but without numerical confirmation. This project will combine PIC simulations with analytical theory, determine whether the FP equation approach is applicable and measure the diffusion and advection coefficients, going beyond FP if necessary, and elucidate the deeper connections between reconnection and turbulence. This project will advance theoretical understanding of relativistic NTPA in collisionless magnetic reconnection and turbulence under a variety of physical conditions, and contribute significantly to understanding the relativistic plasma environments around neutron stars and black holes. By influencing thinking about NTPA in other space and solar plasmas, this work will help to connect plasma physics, astrophysics, and heliospheric physics.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.

在脉冲星风星云、吸积盘日冕和相对论性喷流等不同的天体物理系统中，高度磁化的等离子体有助于将带电粒子加速到非常高的速度。最近的许多进展都是数值的，但这些大型而复杂的模拟需要与一个连贯的理论图景相联系，这也需要更新理论，这些理论早于从计算中获得的许多见解。这正是该项目将提供的，推进我们对各种物理条件下加速的理解，扩展到更接近地球的太空和太阳等离子体，从而帮助在等离子体物理学，天体物理学和日光层物理学之间建立智力桥梁。该研究包括培训，支持和指导研究生以及本科生的各种研究机会。通过与科罗拉多大学菲斯克天文馆的合作，视觉上引人注目的图形将有助于公众对现代科学的理解。具有扩展幂律能量分布的相对论带电粒子被推断存在于许多天体物理系统中，但对非热粒子加速（NTPA）的机制知之甚少。直到最近，第一性原理动力学粒子模拟（PIC）才表明，高度磁化等离子体中的重联和湍流可以有效地导致相对论NTPA。现代PIC模拟的规模和复杂性，以及理论模型先于模拟并且尚未更新的事实，加剧了将累积的数值结果转化为连贯的理论图像的挑战。 NTPA的许多理论都与Fokker-Planck（FP）方程有关，但没有数值证实。本项目将联合收割机PIC模拟与分析理论相结合，确定FP方程方法是否适用，并测量扩散和平流系数，必要时超越FP，并阐明重联和湍流之间更深层次的联系。该项目将推进对各种物理条件下无碰撞磁重联和湍流中相对论NTPA的理论理解，并对理解中子星和黑洞周围的相对论等离子体环境做出重大贡献。通过影响对NTPA在其他空间和太阳等离子体的思考，这项工作将有助于连接等离子体物理学，天体物理学和日光层物理学。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

项目成果

期刊论文数量（14）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Particle Injection and Nonthermal Particle Acceleration in Relativistic Magnetic Reconnection*

相对论磁重联中的粒子注入和非热粒子加速*

DOI：
10.3847/1538-4357/acb7dd
发表时间：
2023
期刊：
The Astrophysical Journal
影响因子：
0
作者：
French, Omar;Guo, Fan;Zhang, Qile;Uzdensky, Dmitri A.
通讯作者：
Uzdensky, Dmitri A.

Production and Persistence of Extreme Two-temperature Plasmas in Radiative Relativistic Turbulence

辐射相对论性湍流中极端两温等离子体的产生和持续

DOI：
10.3847/1538-4357/abcf31
发表时间：
2021
期刊：
The Astrophysical Journal
影响因子：
0
作者：
Zhdankin, Vladimir;Uzdensky, Dmitri A.;Kunz, Matthew W.
通讯作者：
Kunz, Matthew W.

Kinetic simulations of imbalanced turbulence in a relativistic plasma: Net flow and particle acceleration

相对论等离子体中不平衡湍流的动力学模拟：净流和粒子加速

DOI：
10.1093/mnras/stab3209
发表时间：
2021
期刊：
Monthly Notices of the Royal Astronomical Society
影响因子：
4.8
作者：
Hankla, Amelia M;Zhdankin, Vladimir;Werner, Gregory R;Uzdensky, Dmitri A;Begelman, Mitchell C
通讯作者：
Begelman, Mitchell C

Kinetic turbulence in shining pair plasma: intermittent beaming and thermalization by radiative cooling