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Oka M, Birn J, Egedal J, Guo F, Ergun RE, Turner DL, Khotyaintsev Y, Hwang KJ, Cohen IJ, Drake JF. Particle Acceleration by Magnetic Reconnection in Geospace. SPACE SCIENCE REVIEWS 2023; 219:75. [PMID: 37969745 PMCID: PMC10630319 DOI: 10.1007/s11214-023-01011-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 10/05/2023] [Indexed: 11/17/2023]
Abstract
Particles are accelerated to very high, non-thermal energies during explosive energy-release phenomena in space, solar, and astrophysical plasma environments. While it has been established that magnetic reconnection plays an important role in the dynamics of Earth's magnetosphere, it remains unclear how magnetic reconnection can further explain particle acceleration to non-thermal energies. Here we review recent progress in our understanding of particle acceleration by magnetic reconnection in Earth's magnetosphere. With improved resolutions, recent spacecraft missions have enabled detailed studies of particle acceleration at various structures such as the diffusion region, separatrix, jets, magnetic islands (flux ropes), and dipolarization front. With the guiding-center approximation of particle motion, many studies have discussed the relative importance of the parallel electric field as well as the Fermi and betatron effects. However, in order to fully understand the particle acceleration mechanism and further compare with particle acceleration in solar and astrophysical plasma environments, there is a need for further investigation of, for example, energy partition and the precise role of turbulence.
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Affiliation(s)
- Mitsuo Oka
- Space Sciences Laboratory, University of California Berkeley, 7 Gauss Way, Berkeley, 94720 CA USA
| | - Joachim Birn
- Center for Space Plasma Physics, Space Science Institute, 4765 Walnut Street, Boulder, 80301 CO USA
- Los Alamos National Laboratory, Los Alamos, 87545 NM USA
| | - Jan Egedal
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, 53706 WI USA
| | - Fan Guo
- Los Alamos National Laboratory, Los Alamos, 87545 NM USA
| | - Robert E. Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, 1234 Innovation Drive, Boulder, 80303 CO USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, 2000 Colorado Avenue, Boulder, 80309 CO USA
| | - Drew L. Turner
- The Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, 20723 MD USA
| | | | - Kyoung-Joo Hwang
- Southwest Research Institute, 6220 Culebra Road, San Antonio, 78238 TX USA
| | - Ian J. Cohen
- The Johns Hopkins Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, 20723 MD USA
| | - James F. Drake
- Department of Physics, The Institute for Physical Science and Technology and The Joint Space Science Institute, University of Maryland, College Park, 20742 MD USA
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Hasegawa H, Denton RE, Dokgo K, Hwang K, Nakamura TKM, Burch JL. Ion-Scale Magnetic Flux Rope Generated From Electron-Scale Magnetopause Current Sheet: Magnetospheric Multiscale Observations. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2022JA031092. [PMID: 38440152 PMCID: PMC10909477 DOI: 10.1029/2022ja031092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 03/05/2023] [Accepted: 03/08/2023] [Indexed: 03/06/2024]
Abstract
We present in-depth analysis of three southward-moving meso-scale (ion-to magnetohydrodynamic-scale) flux transfer events (FTEs) and subsequent crossing of a reconnecting magnetopause current sheet (MPCS), which were observed on 8 December 2015 by the Magnetospheric Multiscale spacecraft in the subsolar region under southward and duskward magnetosheath magnetic field conditions. We aim to understand the generation mechanism of ion-scale magnetic flux ropes (ISFRs) and to reveal causal relationship among magnetic field structures, electromagnetic energy conversion, and kinetic processes in magnetic reconnection layers. Results from magnetic field reconstruction methods are consistent with a flux rope with a length of about one ion inertial length growing from an electron-scale current sheet (ECS) in the MPCS, supporting the idea that ISFRs can be generated through secondary reconnection in an ECS. Grad-Shafranov reconstruction applied to the three FTEs shows that the FTEs had axial orientations similar to that of the ISFR. This suggests that these FTEs also formed through the same secondary reconnection process, rather than multiple X-line reconnection at spatially separated locations. Four-spacecraft observations of electron pitch-angle distributions and energy conversion rate j · E ' = j · E + v e × B suggest that the ISFR had three-dimensional magnetic topology and secondary reconnection was patchy or bursty. Previously reported positive and negative values of j · E ' , with magnitudes much larger than expected for typical MP reconnection, were seen in both magnetosheath and magnetospheric separatrix regions of the ISFR. Many of them coexisted with bi-directional electron beams and intense electric field fluctuations around the electron gyrofrequency, consistent with their origin in separatrix activities.
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Affiliation(s)
- H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
- Southwest Research InstituteSan AntonioTXUSA
| | - R. E. Denton
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | - K. Dokgo
- Southwest Research InstituteSan AntonioTXUSA
| | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | | | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
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3
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Trattner KJ, Petrinec SM, Fuselier SA. The Location of Magnetic Reconnection at Earth's Magnetopause. SPACE SCIENCE REVIEWS 2021; 217:41. [PMID: 34720216 PMCID: PMC8550343 DOI: 10.1007/s11214-021-00817-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 03/08/2021] [Indexed: 06/13/2023]
Abstract
One of the major questions about magnetic reconnection is how specific solar wind and interplanetary magnetic field conditions influence where reconnection occurs at the Earth's magnetopause. There are two reconnection scenarios discussed in the literature: a) anti-parallel reconnection and b) component reconnection. Early spacecraft observations were limited to the detection of accelerated ion beams in the magnetopause boundary layer to determine the general direction of the reconnection X-line location with respect to the spacecraft. An improved view of the reconnection location at the magnetopause evolved from ionospheric emissions observed by polar-orbiting imagers. These observations and the observations of accelerated ion beams revealed that both scenarios occur at the magnetopause. Improved methodology using the time-of-flight effect of precipitating ions in the cusp regions and the cutoff velocity of the precipitating and mirroring ion populations was used to pinpoint magnetopause reconnection locations for a wide range of solar wind conditions. The results from these methodologies have been used to construct an empirical reconnection X-line model known as the Maximum Magnetic Shear model. Since this model's inception, several tests have confirmed its validity and have resulted in modifications to the model for certain solar wind conditions. This review article summarizes the observational evidence for the location of magnetic reconnection at the Earth's magnetopause, emphasizing the properties and efficacy of the Maximum Magnetic Shear Model.
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Affiliation(s)
| | | | - S. A. Fuselier
- Southwest Research Institute, San Antonio, TX USA
- University of Texas at San Antonio, San Antonio, TX USA
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4
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Petrinec SM, Burch JL, Chandler M, Farrugia CJ, Fuselier SA, Giles BL, Gomez RG, Mukherjee J, Paterson WR, Russell CT, Sibeck DG, Strangeway RJ, Torbert RB, Trattner KJ, Vines SK, Zhao C. Characteristics of Minor Ions and Electrons in Flux Transfer Events Observed by the Magnetospheric Multiscale Mission. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2020; 125:e2020JA027778. [PMID: 32999806 PMCID: PMC7507212 DOI: 10.1029/2020ja027778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 03/18/2020] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
In this study, the ion composition of flux transfer events (FTEs) observed within the magnetosheath proper is examined. These FTEs were observed just upstream of the Earth's postnoon magnetopause by the National Aeronautics and Space Administration (NASA) Magnetospheric Multiscale (MMS) spacecraft constellation. The minor ion characteristics are described using energy spectrograms, flux distributions, and ion moments as the constellation encountered each FTE. In conjunction with electron data and magnetic field observations, such observations provide important contextual information on the formation, topologies, and evolution of FTEs. In particular, minor ions, when combined with the field-aligned streaming of electrons, are reliable indicators of FTE topology. The observations are also placed (i) in context of the solar wind magnetic field configuration, (ii) the connection of the sampled flux tube to the ionosphere, and (iii) the location relative to the modeled reconnection line at the magnetopause. While protons and alpha particles were often depleted within the FTEs relative to the surrounding magnetosheath plasma, the He+ and O+ populations showed clear enhancements either near the center or near the edges of the FTE, and the bulk plasma flow directions are consistent with magnetic reconnection northward of the spacecraft and convection from the dayside toward the flank magnetopause.
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Affiliation(s)
- S. M. Petrinec
- Lockheed Martin Advanced Technology CenterPalo AltoCAUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - M. Chandler
- NASA Marshall Space Flight CenterHuntsvilleALUSA
| | - C. J. Farrugia
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - S. A. Fuselier
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - R. G. Gomez
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | | | | | - C. T. Russell
- Earth and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | | | - R. J. Strangeway
- Earth and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - K. J. Trattner
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - S. K. Vines
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - C. Zhao
- Earth and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
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Akhavan‐Tafti M, Palmroth M, Slavin JA, Battarbee M, Ganse U, Grandin M, Le G, Gershman DJ, Eastwood JP, Stawarz JE. Comparative Analysis of the Vlasiator Simulations and MMS Observations of Multiple X-Line Reconnection and Flux Transfer Events. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2020; 125:e2019JA027410. [PMID: 32999805 PMCID: PMC7507759 DOI: 10.1029/2019ja027410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 03/15/2020] [Accepted: 04/13/2020] [Indexed: 06/11/2023]
Abstract
The Vlasiator hybrid-Vlasov code was developed to investigate global magnetospheric dynamics at ion-kinetic scales. Here we focus on the role of magnetic reconnection in the formation and evolution of magnetic islands at the low-latitude magnetopause, under southward interplanetary magnetic field conditions. The simulation results indicate that (1) the magnetic reconnection ion kinetics, including the Earthward pointing Larmor electric field on the magnetospheric side of an X-point and anisotropic ion distributions, are well-captured by Vlasiator, thus enabling the study of reconnection-driven magnetic island evolution processes, (2) magnetic islands evolve due to continuous reconnection at adjacent X-points, "coalescence" which refers to the merging of neighboring islands to create a larger island, "erosion" during which an island loses magnetic flux due to reconnection, and "division" which involves the splitting of an island into smaller islands, and (3) continuous reconnection at adjacent X-points is the dominant source of magnetic flux and plasma to the outer layers of magnetic islands resulting in cross-sectional growth rates up to + 0.3 RE 2/min. The simulation results are compared to the Magnetospheric Multiscale (MMS) measurements of a chain of ion-scale flux transfer events (FTEs) sandwiched between two dominant X-lines. The MMS measurements similarly reveal (1) anisotropic ion populations and (2) normalized reconnection rate ~0.18, in agreement with theory and the Vlasiator predictions. Based on the simulation results and the MMS measurements, it is estimated that the observed ion-scale FTEs may grow Earth-sized within ~10 min, which is comparable to the average transport time for FTEs formed in the subsolar region to the high-latitude magnetopause. Future simulations shall revisit reconnection-driven island evolution processes with improved spatial resolutions.
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Affiliation(s)
- M. Akhavan‐Tafti
- Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMIUSA
- Laboratoire de Physique des Plasmas (LPP), École Polytechnique, CNRSSorbonne Université, Institut Polytechnique de ParisPalaiseauFrance
| | - M. Palmroth
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - J. A. Slavin
- Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMIUSA
| | - M. Battarbee
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - U. Ganse
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - M. Grandin
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - G. Le
- NASA Goddard Space Flight CenterGreenbeltMDUSA
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6
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Hwang K, Dokgo K, Choi E, Burch JL, Sibeck DG, Giles BL, Hasegawa H, Fu HS, Liu Y, Wang Z, Nakamura TKM, Ma X, Fear RC, Khotyaintsev Y, Graham DB, Shi QQ, Escoubet CP, Gershman DJ, Paterson WR, Pollock CJ, Ergun RE, Torbert RB, Dorelli JC, Avanov L, Russell CT, Strangeway RJ. Magnetic Reconnection Inside a Flux Rope Induced by Kelvin-Helmholtz Vortices. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2020; 125:e2019JA027665. [PMID: 32714734 PMCID: PMC7375157 DOI: 10.1029/2019ja027665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/29/2020] [Accepted: 03/03/2020] [Indexed: 06/11/2023]
Abstract
On 5 May 2017, MMS observed a crater-type flux rope on the dawnside tailward magnetopause with fluctuations. The boundary-normal analysis shows that the fluctuations can be attributed to nonlinear Kelvin-Helmholtz (KH) waves. Reconnection signatures such as flow reversals and Joule dissipation were identified at the leading and trailing edges of the flux rope. In particular, strong northward electron jets observed at the trailing edge indicated midlatitude reconnection associated with the 3-D structure of the KH vortex. The scale size of the flux rope, together with reconnection signatures, strongly supports the interpretation that the flux rope was generated locally by KH vortex-induced reconnection. The center of the flux rope also displayed signatures of guide-field reconnection (out-of-plane electron jets, parallel electron heating, and Joule dissipation). These signatures indicate that an interface between two interlinked flux tubes was undergoing interaction, causing a local magnetic depression, resulting in an M-shaped crater flux rope, as supported by reconstruction.
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Affiliation(s)
- K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - K. Dokgo
- Southwest Research InstituteSan AntonioTXUSA
| | - E. Choi
- Southwest Research InstituteSan AntonioTXUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | - H. S. Fu
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | - Y. Liu
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | - Z. Wang
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | | | - X. Ma
- Physical Sciences DepartmentEmbry‐Riddle Aeronautical UniversityDaytona BeachFLUSA
| | - R. C. Fear
- School of Physics and AstronomyUniversity of SouthamptonSouthamptonUK
| | | | | | - Q. Q. Shi
- School of Earth and Space SciencesPeking UniversityPekingChina
| | - C. P. Escoubet
- European Space Research and Technology CentreNoordwijkthe Netherlands
| | | | | | | | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado at BoulderBoulderCOUSA
| | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | | | - L. Avanov
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- The Goddard Planetary Heliophysics InstituteUniversity of Maryland, Baltimore CountyBaltimoreMDUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of California, Los AngelesLos AngelesCAUSA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary PhysicsUniversity of California, Los AngelesLos AngelesCAUSA
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7
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Jara-Almonte J, Ji H, Yamada M, Yoo J, Fox W. Laboratory Observation of Resistive Electron Tearing in a Two-Fluid Reconnecting Current Sheet. PHYSICAL REVIEW LETTERS 2016; 117:095001. [PMID: 27610861 DOI: 10.1103/physrevlett.117.095001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Indexed: 06/06/2023]
Abstract
The spontaneous formation of plasmoids via the resistive electron tearing of a reconnecting current sheet is observed in the laboratory. These experiments are performed during driven, antiparallel reconnection in the two-fluid regime within the Magnetic Reconnection Experiment. It is found that plasmoids are present even at a very low Lundquist number, and the number of plasmoids scales with both the current sheet aspect ratio and the Lundquist number. The reconnection electric field increases when plasmoids are formed, leading to an enhanced reconnection rate.
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Affiliation(s)
| | - Hantao Ji
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - Masaaki Yamada
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - Jongsoo Yoo
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - William Fox
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
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8
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Olson J, Egedal J, Greess S, Myers R, Clark M, Endrizzi D, Flanagan K, Milhone J, Peterson E, Wallace J, Weisberg D, Forest CB. Experimental Demonstration of the Collisionless Plasmoid Instability below the Ion Kinetic Scale during Magnetic Reconnection. PHYSICAL REVIEW LETTERS 2016; 116:255001. [PMID: 27391729 DOI: 10.1103/physrevlett.116.255001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Indexed: 06/06/2023]
Abstract
The spontaneous formation of magnetic islands is observed in driven, antiparallel magnetic reconnection on the Terrestrial Reconnection Experiment. We here provide direct experimental evidence that the plasmoid instability is active at the electron scale inside the ion diffusion region in a low collisional regime. The experiments show the island formation occurs at a smaller system size than predicted by extended magnetohydrodynamics or fully collisionless simulations. This more effective seeding of magnetic islands emphasizes their importance to reconnection in naturally occurring 3D plasmas.
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Affiliation(s)
- J Olson
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - J Egedal
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - S Greess
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - R Myers
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - M Clark
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - D Endrizzi
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - K Flanagan
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - J Milhone
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - E Peterson
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - J Wallace
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - D Weisberg
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
| | - C B Forest
- Department of Physics, University of Wisconsin-Madison, 1150 University Avenue, Madison, Wisconsin 53706, USA
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9
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Ergun RE, Goodrich KA, Wilder FD, Holmes JC, Stawarz JE, Eriksson S, Sturner AP, Malaspina DM, Usanova ME, Torbert RB, Lindqvist PA, Khotyaintsev Y, Burch JL, Strangeway RJ, Russell CT, Pollock CJ, Giles BL, Hesse M, Chen LJ, Lapenta G, Goldman MV, Newman DL, Schwartz SJ, Eastwood JP, Phan TD, Mozer FS, Drake J, Shay MA, Cassak PA, Nakamura R, Marklund G. Magnetospheric Multiscale Satellites Observations of Parallel Electric Fields Associated with Magnetic Reconnection. PHYSICAL REVIEW LETTERS 2016; 116:235102. [PMID: 27341241 DOI: 10.1103/physrevlett.116.235102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Indexed: 06/06/2023]
Abstract
We report observations from the Magnetospheric Multiscale satellites of parallel electric fields (E_{∥}) associated with magnetic reconnection in the subsolar region of the Earth's magnetopause. E_{∥} events near the electron diffusion region have amplitudes on the order of 100 mV/m, which are significantly larger than those predicted for an antiparallel reconnection electric field. This Letter addresses specific types of E_{∥} events, which appear as large-amplitude, near unipolar spikes that are associated with tangled, reconnected magnetic fields. These E_{∥} events are primarily in or near a current layer near the separatrix and are interpreted to be double layers that may be responsible for secondary reconnection in tangled magnetic fields or flux ropes. These results are telling of the three-dimensional nature of magnetopause reconnection and indicate that magnetopause reconnection may be often patchy and/or drive turbulence along the separatrix that results in flux ropes and/or tangled magnetic fields.
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Affiliation(s)
- R E Ergun
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - K A Goodrich
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - F D Wilder
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J C Holmes
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J E Stawarz
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S Eriksson
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - A P Sturner
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D M Malaspina
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - M E Usanova
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - P-A Lindqvist
- KTH Royal Institute of Technology, Stockholm, Sweden
| | - Y Khotyaintsev
- Swedish Institute of Space Physics (Uppsala), Uppsala, Sweden
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - M Hesse
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - L J Chen
- University of Maryland, College Park, Maryland 20742, USA
| | - G Lapenta
- Leuven Universiteit, Leuven, Belgium
| | - M V Goldman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - D L Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - S J Schwartz
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
- The Blackett Laboratory, Imperial College London, United Kingdom
| | - J P Eastwood
- The Blackett Laboratory, Imperial College London, United Kingdom
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - F S Mozer
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J Drake
- University of Maryland, College Park, Maryland 20742, USA
| | - M A Shay
- University of Delaware, Newark, Delaware 19716, USA
| | - P A Cassak
- West Virginia University, Morgantown, West Virginia 26506, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - G Marklund
- KTH Royal Institute of Technology, Stockholm, Sweden
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10
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Eastwood JP, Phan TD, Cassak PA, Gershman DJ, Haggerty C, Malakit K, Shay MA, Mistry R, Øieroset M, Russell CT, Slavin JA, Argall MR, Avanov LA, Burch JL, Chen LJ, Dorelli JC, Ergun RE, Giles BL, Khotyaintsev Y, Lavraud B, Lindqvist PA, Moore TE, Nakamura R, Paterson W, Pollock C, Strangeway RJ, Torbert RB, Wang S. Ion-scale secondary flux ropes generated by magnetopause reconnection as resolved by MMS. GEOPHYSICAL RESEARCH LETTERS 2016; 43:4716-4724. [PMID: 27635105 PMCID: PMC5001194 DOI: 10.1002/2016gl068747] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/28/2016] [Accepted: 04/29/2016] [Indexed: 06/06/2023]
Abstract
New Magnetospheric Multiscale (MMS) observations of small-scale (~7 ion inertial length radius) flux transfer events (FTEs) at the dayside magnetopause are reported. The 10 km MMS tetrahedron size enables their structure and properties to be calculated using a variety of multispacecraft techniques, allowing them to be identified as flux ropes, whose flux content is small (~22 kWb). The current density, calculated using plasma and magnetic field measurements independently, is found to be filamentary. Intercomparison of the plasma moments with electric and magnetic field measurements reveals structured non-frozen-in ion behavior. The data are further compared with a particle-in-cell simulation. It is concluded that these small-scale flux ropes, which are not seen to be growing, represent a distinct class of FTE which is generated on the magnetopause by secondary reconnection.
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Affiliation(s)
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - P. A. Cassak
- Department of Physics and AstronomyWest Virginia UniversityMorgantownWest VirginiaUSA
| | - D. J. Gershman
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
| | - C. Haggerty
- Department of Physics and AstronomyUniversity of DelawareNewarkDelawareUSA
| | - K. Malakit
- Department of PhysicsMahidol UniversityBangkokThailand
| | - M. A. Shay
- Department of Physics and AstronomyUniversity of DelawareNewarkDelawareUSA
| | - R. Mistry
- Blackett LaboratoryImperial College LondonLondonUK
| | - M. Øieroset
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - C. T. Russell
- Department of Earth, Planetary and Space SciencesUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - J. A. Slavin
- Department of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMichiganUSA
| | - M. R. Argall
- Institute for the Study of Earth, Oceans and SpaceUniversity of New HampshireDurhamNew HampshireUSA
| | - L. A. Avanov
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTexasUSA
| | - L. J. Chen
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
| | - J. C. Dorelli
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderColoradoUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | | | - B. Lavraud
- Institut de Recherche en Astrophysique et PlanétologieUniversité de ToulouseToulouseFrance
- Centre National de la Recherche Scientifique, UMR 5277ToulouseFrance
| | - P. A. Lindqvist
- School of Electrical EngineeringRoyal Institute of TechnologyStockholmSweden
| | - T. E. Moore
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - W. Paterson
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | | | - R. J. Strangeway
- Department of Earth, Planetary and Space SciencesUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. B. Torbert
- Institute for the Study of Earth, Oceans and SpaceUniversity of New HampshireDurhamNew HampshireUSA
- Southwest Research InstituteSan AntonioTexasUSA
| | - S. Wang
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
- Department of AstronomyUniversity of MarylandCollege ParkMarylandUSA
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Huang S, Pang Y, Yuan Z, Deng X, He J, Zhou M, Fu H, Fu S, Li H, Wang D, Li H. Observation of directional change of core field inside flux ropes within one reconnection diffusion region in the Earth’s magnetotail. CHINESE SCIENCE BULLETIN-CHINESE 2014. [DOI: 10.1007/s11434-014-0583-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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