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Li JH, Yang F, Zhou XZ, Zong QG, Artemyev AV, Rankin R, Shi Q, Yao S, Liu H, He J, Pu Z, Xiao C, Liu J, Pollock C, Le G, Burch JL. Self-consistent kinetic model of nested electron- and ion-scale magnetic cavities in space plasmas. Nat Commun 2020; 11:5616. [PMID: 33154395 PMCID: PMC7644639 DOI: 10.1038/s41467-020-19442-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 10/15/2020] [Indexed: 12/05/2022] Open
Abstract
NASA’s Magnetospheric Multi-Scale (MMS) mission is designed to explore the proton- and electron-gyroscale kinetics of plasma turbulence where the bulk of particle acceleration and heating takes place. Understanding the nature of cross-scale structures ubiquitous as magnetic cavities is important to assess the energy partition, cascade and conversion in the plasma universe. Here, we present theoretical insight into magnetic cavities by deriving a self-consistent, kinetic theory of these coherent structures. By taking advantage of the multipoint measurements from the MMS constellation, we demonstrate that our kinetic model can utilize magnetic cavity observations by one MMS spacecraft to predict measurements from a second/third spacecraft. The methodology of “observe and predict” validates the theory we have derived, and confirms that nested magnetic cavities are self-organized plasma structures supported by trapped proton and electron populations in analogous to the classical theta-pinches in laboratory plasmas. Magnetic cavities play important roles in the energy cascade, conversion and dissipation in turbulent plasmas. Here, the authors show a theoretical insight into magnetic cavities by deriving a self-consistent, kinetic theory of these coherent structures.
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Affiliation(s)
- Jing-Huan Li
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China
| | - Fan Yang
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China
| | - Xu-Zhi Zhou
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China.
| | - Qiu-Gang Zong
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China.
| | - Anton V Artemyev
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA, 90095, USA.,Space Research Institute, Russian Academy of Sciences, Moscow, 117997, Russia
| | - Robert Rankin
- Department of Physics, University of Alberta, Edmonton, AB, T6G2G7, Canada
| | - Quanqi Shi
- Institute of Space Sciences, Shandong University, Weihai, 264209, China
| | - Shutao Yao
- Institute of Space Sciences, Shandong University, Weihai, 264209, China
| | - Han Liu
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China
| | - Jiansen He
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China
| | - Zuyin Pu
- School of Earth and Space Sciences, Peking University, 100871, Beijing, China
| | - Chijie Xiao
- School of Physics, Peking University, Beijing, 100871, China
| | - Ji Liu
- National Space Science Center, Chinese Academy of Sciences, Beijing, 100190, China
| | | | - Guan Le
- NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA
| | - James L Burch
- Southwest Research Institute, San Antonio, TX, 78238, USA
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Electron Bernstein waves driven by electron crescents near the electron diffusion region. Nat Commun 2020; 11:141. [PMID: 31919351 PMCID: PMC6952373 DOI: 10.1038/s41467-019-13920-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 12/05/2019] [Indexed: 11/08/2022] Open
Abstract
The Magnetospheric Multiscale (MMS) spacecraft encounter an electron diffusion region (EDR) of asymmetric magnetic reconnection at Earth's magnetopause. The EDR is characterized by agyrotropic electron velocity distributions on both sides of the neutral line. Various types of plasma waves are produced by the magnetic reconnection in and near the EDR. Here we report large-amplitude electron Bernstein waves (EBWs) at the electron-scale boundary of the Hall current reversal. The finite gyroradius effect of the outflow electrons generates the crescent-shaped agyrotropic electron distributions, which drive the EBWs. The EBWs propagate toward the central EDR. The amplitude of the EBWs is sufficiently large to thermalize and diffuse electrons around the EDR. The EBWs contribute to the cross-field diffusion of the electron-scale boundary of the Hall current reversal near the EDR.
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Dokgo K, Hwang K, Burch JL, Choi E, Yoon PH, Sibeck DG, Graham DB. High-Frequency Wave Generation in Magnetotail Reconnection: Nonlinear Harmonics of Upper Hybrid Waves. GEOPHYSICAL RESEARCH LETTERS 2019; 46:7873-7882. [PMID: 31598022 PMCID: PMC6774311 DOI: 10.1029/2019gl083361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 06/12/2019] [Accepted: 06/30/2019] [Indexed: 06/10/2023]
Abstract
MMS3 spacecraft passed the vicinity of the electron diffusion region of magnetotail reconnection on 3 July 2017, observing discrepancies between perpendicular electron bulk velocities and E → × B → drift, and agyrotropic electron crescent distributions. Analyzing linear wave dispersions, Burch et al. (2019, https://doi.org/10.1029/2019GL082471) showed the electron crescent generates high-frequency waves. We investigate harmonics of upper-hybrid (UH) waves using both observation and particle-in-cell (PIC) simulation, and the generation of electromagnetic radiation from PIC simulation. Harmonics of UH are linearly polarized and propagate along the perpendicular direction to the ambient magnetic field. Compared with two-dimensional PIC simulation and nonlinear kinetic theory, we show that the nonlinear beam-plasma interaction between the agyrotropic electrons and the core electrons generates harmonics of UH. Moreover, PIC simulation shows that agyrotropic electron beam can lead to electromagnetic (EM) radiation at the plasma frequency and harmonics.
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Affiliation(s)
| | | | | | - Eunjin Choi
- Southwest Research InstituteSan AntonioTXUSA
| | - Peter H. Yoon
- Institute for Physical Science and TechnologyUniversity of MarylandCollege ParkMDUSA
- School of Space ResearchKyung Hee UniversityYonginSouth Korea
- Korea Astronomy and Space Science InstituteDaejeonSouth Korea
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Egedal J, Le A, Daughton W, Wetherton B, Cassak PA, Burch JL, Lavraud B, Dorelli J, Gershman DJ, Avanov LA. Spacecraft Observations of Oblique Electron Beams Breaking the Frozen-In Law During Asymmetric Reconnection. PHYSICAL REVIEW LETTERS 2018; 120:055101. [PMID: 29481157 DOI: 10.1103/physrevlett.120.055101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Indexed: 06/08/2023]
Abstract
Fully kinetic simulations of asymmetric magnetic reconnection reveal the presence of magnetic-field-aligned beams of electrons flowing toward the topological magnetic x line. Within the ∼6d_{e} electron-diffusion region, the beams become oblique to the local magnetic field, providing a unique signature of the electron-diffusion region where the electron frozen-in law is broken. The numerical predictions are confirmed by in situ Magnetospheric Multiscale spacecraft observations during asymmetric reconnection at Earth's dayside magnetopause.
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Affiliation(s)
- J Egedal
- Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - A Le
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - W Daughton
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - B Wetherton
- Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - P A Cassak
- Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, UMR 5277, Toulouse, France
| | - J Dorelli
- Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - D J Gershman
- Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - L A Avanov
- Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
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Rager AC, Dorelli JC, Gershman DJ, Uritsky V, Avanov LA, Torbert RB, Burch JL, Ergun RE, Egedal J, Schiff C, Shuster JR, Giles BL, Paterson WR, Pollock CJ, Strangeway RJ, Russell CT, Lavraud B, Coffey VN, Saito Y. Electron Crescent Distributions as a Manifestation of Diamagnetic Drift in an Electron-Scale Current Sheet: Magnetospheric Multiscale Observations Using New 7.5 ms Fast Plasma Investigation Moments. GEOPHYSICAL RESEARCH LETTERS 2018; 45:578-584. [PMID: 29576666 PMCID: PMC5856066 DOI: 10.1002/2017gl076260] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 12/25/2017] [Accepted: 01/07/2018] [Indexed: 06/08/2023]
Abstract
We report Magnetospheric Multiscale observations of electron pressure gradient electric fields near a magnetic reconnection diffusion region using a new technique for extracting 7.5 ms electron moments from the Fast Plasma Investigation. We find that the deviation of the perpendicular electron bulk velocity from E × B drift in the interval where the out-of-plane current density is increasing can be explained by the diamagnetic drift. In the interval where the out-of-plane current is transitioning to in-plane current, the electron momentum equation is not satisfied at 7.5 ms resolution.
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Affiliation(s)
- A. C. Rager
- Department of PhysicsCatholic University of AmericaWashingtonDCUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | | | - V. Uritsky
- Department of PhysicsCatholic University of AmericaWashingtonDCUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - L. A. Avanov
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - R. B. Torbert
- Department of PhysicsUniversity of New HampshireDurhamNHUSA
- Southwest Research InstituteSan AntonioTXUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - R. E. Ergun
- Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - J. Egedal
- Department of PhysicsUniversity of WisconsinMadisonWIUSA
| | - C. Schiff
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - J. R. Shuster
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | | | - R. J. Strangeway
- Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - C. T. Russell
- Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - B. Lavraud
- Research Institute in Astrophysics and PlanetologyToulouseFrance
| | - V. N. Coffey
- NASA Marshall Space Flight CenterHuntsvilleALUSA
| | - Y. Saito
- Institute for Space and Astronautical ScienceSagamiharaJapan
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