1
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Kitamura N, Amano T, Omura Y, Boardsen SA, Gershman DJ, Miyoshi Y, Kitahara M, Katoh Y, Kojima H, Nakamura S, Shoji M, Saito Y, Yokota S, Giles BL, Paterson WR, Pollock CJ, Barrie AC, Skeberdis DG, Kreisler S, Le Contel O, Russell CT, Strangeway RJ, Lindqvist PA, Ergun RE, Torbert RB, Burch JL. Direct observations of energy transfer from resonant electrons to whistler-mode waves in magnetosheath of Earth. Nat Commun 2022; 13:6259. [PMID: 36307443 PMCID: PMC9616889 DOI: 10.1038/s41467-022-33604-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 09/22/2022] [Indexed: 11/30/2022] Open
Abstract
Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA’s Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations. Excitation of whistler-mode waves by cyclotron instability is considered as the likely generation process of the waves. Here, the authors show direct observational evidence for locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves in Earth’s magnetosheath.
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Affiliation(s)
- N Kitamura
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan. .,Department of Earth and Planetary Science, Graduate School of Science, the University of Tokyo, Tokyo, Japan.
| | - T Amano
- Department of Earth and Planetary Science, Graduate School of Science, the University of Tokyo, Tokyo, Japan
| | - Y Omura
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan
| | - S A Boardsen
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Goddard Planetary Heliophysics Institute, University of Maryland, Baltimore County, MD, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - Y Miyoshi
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - M Kitahara
- Department of Geophysics, Graduate school of Science, Tohoku University, Sendai, Japan
| | - Y Katoh
- Department of Geophysics, Graduate school of Science, Tohoku University, Sendai, Japan
| | - H Kojima
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan
| | - S Nakamura
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - M Shoji
- Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
| | - Y Saito
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - S Yokota
- Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | - A C Barrie
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Aurora Engineering, Potomac, MD, USA
| | - D G Skeberdis
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,a.i. solutions Inc, Lanham, MD, USA
| | - S Kreisler
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Aurora Engineering, Potomac, MD, USA
| | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Sorbonne Université/Université Paris-Saclay/Observatoire de Paris/Ecole Polytechnique Institut Polytechnique de Paris, Paris, France
| | - C T Russell
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - R J Strangeway
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | | | - R E Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA
| | - R B Torbert
- Department of Physics, University of New Hampshire, Durham, NH, USA.,Southwest Research Institute, San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
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2
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Hasegawa H, Denton RE, Nakamura TKM, Genestreti KJ, Phan TD, Nakamura R, Hwang K, Ahmadi N, Shi QQ, Hesse M, Burch JL, Webster JM, Torbert RB, Giles BL, Gershman DJ, Russell CT, Strangeway RJ, Wei HY, Lindqvist P, Khotyaintsev YV, Ergun RE, Saito Y. Magnetic Field Annihilation in a Magnetotail Electron Diffusion Region With Electron-Scale Magnetic Island. J Geophys Res Space Phys 2022; 127:e2022JA030408. [PMID: 36248013 PMCID: PMC9541864 DOI: 10.1029/2022ja030408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/27/2022] [Accepted: 06/20/2022] [Indexed: 06/16/2023]
Abstract
We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic-to-electron energy conversion in an electron-scale current sheet. Multi-spacecraft analysis for the magnetic field reconstruction shows that an electron-scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X-type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X-point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk-flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron-scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma.
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Affiliation(s)
- H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | - R. E. Denton
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | - T. K. M. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of PhysicsUniversity of GrazGrazAustria
| | | | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - N. Ahmadi
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
| | - Q. Q. Shi
- Shandong Provincial Key Laboratory of Optical Astronomy and Solar‐Terrestrial EnvironmentInstitute of Space SciencesShandong UniversityWeihaiChina
| | - M. Hesse
- NASA Ames Research CenterMoffett FieldCAUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - R. B. Torbert
- Institute of PhysicsUniversity of GrazGrazAustria
- Physics DepartmentUniversity of New HampshireDurhamNHUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - H. Y. Wei
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | | | | | - R. E. Ergun
- Department of Astrophysical and Planetary SciencesUniversity of ColoradoBoulderCOUSA
| | - Y. Saito
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
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3
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Vines SK, Anderson BJ, Allen RC, Denton RE, Engebretson MJ, Johnson JR, Toledo‐Redondo S, Lee JH, Turner DL, Ergun RE, Strangeway RJ, Russell CT, Wei H, Torbert RB, Fuselier SA, Giles BL, Burch JL. Determining EMIC Wave Vector Properties Through Multi-Point Measurements: The Wave Curl Analysis. J Geophys Res Space Phys 2021; 126:e2020JA028922. [PMID: 33868890 PMCID: PMC8047877 DOI: 10.1029/2020ja028922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/08/2021] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
Electromagnetic ion cyclotron (EMIC) waves play important roles in particle loss processes in the magnetosphere. Determining the evolution of EMIC waves as they propagate and how this evolution affects wave-particle interactions requires accurate knowledge of the wave vector, k. We present a technique using the curl of the wave magnetic field to determine k observationally, enabled by the unique configuration and instrumentation of the Magnetospheric MultiScale (MMS) spacecraft. The wave curl analysis is demonstrated for synthetic arbitrary electromagnetic waves with varying properties typical of observed EMIC waves. The method is also applied to an EMIC wave interval observed by MMS on October 28, 2015. The derived wave properties and k from the wave curl analysis for the observed EMIC wave are compared with the Waves in Homogenous, Anisotropic, Multi-component Plasma (WHAMP) wave dispersion solution and with results from other single- and multi-spacecraft techniques. We find good agreement between k from the wave curl analysis, k determined from other observational techniques, and k determined from WHAMP. Additionally, the variation of k due to the time and frequency intervals used in the wave curl analysis is explored. This exploration demonstrates that the method is robust when applied to a wave containing at least 3-4 wave periods and over a rather wide frequency range encompassing the peak wave emission. These results provide confidence that we are able to directly determine the wave vector properties using this multi-spacecraft method implementation, enabling systematic studies of EMIC wave k properties with MMS.
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Affiliation(s)
- S. K. Vines
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - B. J. Anderson
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. C. Allen
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. E. Denton
- Department of Physics and AstronomyDartmouth CollegeHanoverNHUSA
| | | | - J. R. Johnson
- Department of EngineeringAndrews UniversityBerrien SpringsMIUSA
| | - S. Toledo‐Redondo
- Department of Electromagnetism and ElectronicsUniversity of MurciaMurciaSpain
| | - J. H. Lee
- The Aerospace CorporationEl SegundoCAUSA
| | - D. L. Turner
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado at BoulderBoulderCOUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesInstitute for Geophysics and Planetary PhysicsUniversity of California at Los AngelesLos AngelesCAUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesInstitute for Geophysics and Planetary PhysicsUniversity of California at Los AngelesLos AngelesCAUSA
| | - H. Wei
- Department of Earth, Planetary, and Space SciencesInstitute for Geophysics and Planetary PhysicsUniversity of California at Los AngelesLos AngelesCAUSA
| | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
- Southwest Research InstituteSan AntonioTXUSA
| | - 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
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
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4
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Eastwood JP, Goldman MV, Phan TD, Stawarz JE, Cassak PA, Drake JF, Newman D, Lavraud B, Shay MA, Ergun RE, Burch JL, Gershman DJ, Giles BL, Lindqvist PA, Torbert RB, Strangeway RJ, Russell CT. Energy Flux Densities near the Electron Dissipation Region in Asymmetric Magnetopause Reconnection. Phys Rev Lett 2020; 125:265102. [PMID: 33449730 DOI: 10.1103/physrevlett.125.265102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 10/29/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Magnetic reconnection is of fundamental importance to plasmas because of its role in releasing and repartitioning stored magnetic energy. Previous results suggest that this energy is predominantly released as ion enthalpy flux along the reconnection outflow. Using Magnetospheric Multiscale data we find the existence of very significant electron energy flux densities in the vicinity of the magnetopause electron dissipation region, orthogonal to the ion energy outflow. These may significantly impact models of electron transport, wave generation, and particle acceleration.
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Affiliation(s)
- J P Eastwood
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - M V Goldman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J E Stawarz
- The Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - P A Cassak
- Department of Physics and Astronomy and Center for KINETIC Plasma Physics, West Virginia University, Morgantown, West Virginia 26506, USA
| | - J F Drake
- Department of Physics/Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA
| | - D Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - B Lavraud
- Laboratoire d'Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France
- Institut de Recherche en Astrophysique et Planétologie, CNRS, CNES, Université de Toulouse, 31028 Toulouse Cedex 4, France
| | - M A Shay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - R E Ergun
- LASP/Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - D J Gershman
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - P A Lindqvist
- KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - R B Torbert
- Southwest Research Institute, San Antonio, Texas 78238, USA
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - R J Strangeway
- Institute of Geophysics, Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095, USA
| | - C T Russell
- Institute of Geophysics, Earth, Planetary, and Space Sciences, University of California, Los Angeles, Los Angeles, California 90095, USA
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5
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Fuselier SA, Dayeh MA, Galli A, Funsten HO, Schwadron NA, Petrinec SM, Trattner KJ, McComas DJ, Burch JL, Toledo‐Redondo S, Szalay JR, Strangeway RJ. Neutral Atom Imaging of the Solar Wind-Magnetosphere-Exosphere Interaction Near the Subsolar Magnetopause. Geophys Res Lett 2020; 47:e2020GL089362. [PMID: 33380756 PMCID: PMC7757190 DOI: 10.1029/2020gl089362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/13/2020] [Accepted: 09/02/2020] [Indexed: 06/01/2023]
Abstract
Energetic neutral atoms (ENAs) created by charge-exchange of ions with the Earth's hydrogen exosphere near the subsolar magnetopause yield information on the distribution of plasma in the outer magnetosphere and magnetosheath. ENA observations from the Interstellar Boundary Explorer (IBEX) are used to image magnetosheath plasma and, for the first time, low-energy magnetospheric plasma near the magnetopause. These images show that magnetosheath plasma is distributed fairly evenly near the subsolar magnetopause; however, low-energy magnetospheric plasma is not distributed evenly in the outer magnetosphere. Simultaneous images and in situ observations from the Magnetospheric Multiscale (MMS) spacecraft from November 2015 (during the solar cycle declining phase) are used to derive the exospheric density. The ~11-17 cm-3 density at 10 RE is similar to that obtained previously for solar minimum. Thus, these combined results indicate that the exospheric density 10 RE from the Earth may have a weak dependence on solar cycle.
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Affiliation(s)
- S. A. Fuselier
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - M. A. Dayeh
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - A. Galli
- Physics InstituteUniversity of BernBernSwitzerland
| | | | | | - S. M. Petrinec
- Lockheed Martin Advanced Technology CenterPalo AltoCAUSA
| | - K. J. Trattner
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - D. J. McComas
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - S. Toledo‐Redondo
- Institut de Recherche en Astrophysique et PlanétologieUniversité de ToulouseToulouseFrance
- Department of Electromagnetism and ElectronicsUniversity of MurciaMurciaSpain
| | - J. R. Szalay
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - R. J. Strangeway
- Earth and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
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6
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Angelopoulos V, Tsai E, Bingley L, Shaffer C, Turner DL, Runov A, Li W, Liu J, Artemyev AV, Zhang XJ, Strangeway RJ, Wirz RE, Shprits YY, Sergeev VA, Caron RP, Chung M, Cruce P, Greer W, Grimes E, Hector K, Lawson MJ, Leneman D, Masongsong EV, Russell CL, Wilkins C, Hinkley D, Blake JB, Adair N, Allen M, Anderson M, Arreola-Zamora M, Artinger J, Asher J, Branchevsky D, Capitelli MR, Castro R, Chao G, Chung N, Cliffe M, Colton K, Costello C, Depe D, Domae BW, Eldin S, Fitzgibbon L, Flemming A, Fox I, Frederick DM, Gilbert A, Gildemeister A, Gonzalez A, Hesford B, Jha S, Kang N, King J, Krieger R, Lian K, Mao J, McKinney E, Miller JP, Norris A, Nuesca M, Palla A, Park ESY, Pedersen CE, Qu Z, Rozario R, Rye E, Seaton R, Subramanian A, Sundin SR, Tan A, Turner W, Villegas AJ, Wasden M, Wing G, Wong C, Xie E, Yamamoto S, Yap R, Zarifian A, Zhang GY. The ELFIN Mission. Space Sci Rev 2020; 216:103. [PMID: 32831412 PMCID: PMC7413588 DOI: 10.1007/s11214-020-00721-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/09/2020] [Indexed: 06/11/2023]
Abstract
The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (Torbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (Tspin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.
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Affiliation(s)
- V Angelopoulos
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - E Tsai
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - L Bingley
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - C Shaffer
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Tyvak Nano-Satellite Systems, Inc., Irvine, CA 92618 USA
| | - D L Turner
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723 USA
| | - A Runov
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - W Li
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Department of Astronomy and Center for Space Physics, Boston University, Boston, MA 02215 USA
| | - J Liu
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - A V Artemyev
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - X-J Zhang
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - R J Strangeway
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - R E Wirz
- Mechanical and Aerospace Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
| | - Y Y Shprits
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- GFZ German Research Centre for Geosciences, Potsdam, 14473 Germany
| | - V A Sergeev
- Saint Petersburg State University, St. Petersburg, 199034 Russia
| | - R P Caron
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - M Chung
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723 USA
| | - P Cruce
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Northrop Grumman Aerospace Systems, Redondo Beach, CA 90278 USA
| | - W Greer
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - E Grimes
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - K Hector
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Raytheon Space and Airborne Systems, El Segundo, CA 90245 USA
| | - M J Lawson
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - D Leneman
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - E V Masongsong
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - C L Russell
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - C Wilkins
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - D Hinkley
- The Aerospace Corporation, El Segundo, CA 90245 USA
| | - J B Blake
- The Aerospace Corporation, El Segundo, CA 90245 USA
| | - N Adair
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Millenium Space Systems, El Segundo, CA 90245 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - M Allen
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Northrop Grumman Aerospace Systems, Redondo Beach, CA 90278 USA
| | - M Anderson
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Aptiv, Agoura Hills, CA 91301 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - M Arreola-Zamora
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - J Artinger
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Physics and Astronomy Department, University of California, Los Angeles, CA 90095 USA
| | - J Asher
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723 USA
| | - D Branchevsky
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- The Aerospace Corporation, El Segundo, CA 90245 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - M R Capitelli
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Millenium Space Systems, El Segundo, CA 90245 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - R Castro
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Raytheon Space and Airborne Systems, El Segundo, CA 90245 USA
| | - G Chao
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: The Boeing Company, Long Beach, CA 90808 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - N Chung
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: SF Motors, Santa Clara, CA 95054 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - M Cliffe
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: SpaceX, Hawthorne, CA 90250 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - K Colton
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Planet Labs, Inc., San Francisco, CA 94107 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - C Costello
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Computer Science Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - D Depe
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Electrical and Computer Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - B W Domae
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Electrical and Computer Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - S Eldin
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Electrical and Computer Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - L Fitzgibbon
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Tyvak Nano-Satellite Systems, Inc., Irvine, CA 92618 USA
| | - A Flemming
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Northrop Grumman Aerospace Systems, Redondo Beach, CA 90278 USA
| | - I Fox
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Mechanical and Aerospace Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
| | - D M Frederick
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Millenium Space Systems, El Segundo, CA 90245 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - A Gilbert
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Electrical and Computer Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - A Gildemeister
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Northrop Grumman Aerospace Systems, Redondo Beach, CA 90278 USA
| | - A Gonzalez
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: SpaceX, Hawthorne, CA 90250 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - B Hesford
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Jet Propulsion Laboratory, Pasadena, CA 91109 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - S Jha
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Computer Science Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - N Kang
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Millenium Space Systems, El Segundo, CA 90245 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - J King
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Computer Science Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - R Krieger
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Mercedes-Benz Research and Development North America, Long Beach, CA 90810 USA
| | - K Lian
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Northrop Grumman Aerospace Systems, Redondo Beach, CA 90278 USA
| | - J Mao
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Verona, WI 53593 USA
| | - E McKinney
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: California State Polytechnic University, Pomona, CA 91768 USA
| | - J P Miller
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Computer Science Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - A Norris
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
| | - M Nuesca
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Computer Science Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - A Palla
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Computer Science Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - E S Y Park
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Economics Department, University of California, Los Angeles, CA 90095 USA
| | - C E Pedersen
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Mechanical and Aerospace Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
| | - Z Qu
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Mechanical and Aerospace Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
| | - R Rozario
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: SpaceX, Hawthorne, CA 90250 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - E Rye
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Electrical and Computer Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - R Seaton
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Mechanical and Aerospace Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
| | - A Subramanian
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Northrop Grumman Aerospace Systems, Redondo Beach, CA 90278 USA
| | - S R Sundin
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Tyvak Nano-Satellite Systems, Inc., Irvine, CA 92618 USA
| | - A Tan
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Experior Laboratories, Oxnard, CA 93033 USA
| | - W Turner
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Physics and Astronomy Department, University of California, Los Angeles, CA 90095 USA
| | - A J Villegas
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Physics and Astronomy Department, University of California, Los Angeles, CA 90095 USA
| | - M Wasden
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Mechanical and Aerospace Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
| | - G Wing
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Computer Science Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - C Wong
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Physics and Astronomy Department, University of California, Los Angeles, CA 90095 USA
| | - E Xie
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Electrical and Computer Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - S Yamamoto
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Mechanical and Aerospace Engineering Department, Henry Samueli School of Engineering, University of California, Los Angeles, CA 90095 USA
| | - R Yap
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Mathematics Department, University of California, Los Angeles, CA 90095 USA
| | - A Zarifian
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Present Address: Jet Propulsion Laboratory, Pasadena, CA 91109 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
| | - G Y Zhang
- Earth, Planetary, and Space Sciences Department, University of California, Los Angeles, CA 90095 USA
- Institute of Geophysics and Planetary Physics, University of California, San Diego, CA USA
- Present Address: Qualcomm, San Diego, CA 92121 USA
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7
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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. J Geophys Res Space Phys 2020; 125:e2020JA027778. [PMID: 32999806 PMCID: PMC7507212 DOI: 10.1029/2020ja027778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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8
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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. J Geophys Res Space Phys 2020; 125:e2019JA027665. [PMID: 32714734 PMCID: PMC7375157 DOI: 10.1029/2019ja027665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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9
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Hwang K, Choi E, Dokgo K, Burch JL, Sibeck DG, Giles BL, Goldstein ML, Paterson WR, Pollock CJ, Shi QQ, Fu H, Hasegawa H, Gershman DJ, Khotyaintsev Y, Torbert RB, Ergun RE, Dorelli JC, Avanov L, Russell CT, Strangeway RJ. Electron Vorticity Indicative of the Electron Diffusion Region of Magnetic Reconnection. Geophys Res Lett 2019; 46:6287-6296. [PMID: 31598018 PMCID: PMC6774273 DOI: 10.1029/2019gl082710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/08/2019] [Accepted: 05/28/2019] [Indexed: 06/10/2023]
Abstract
While vorticity defined as the curl of the velocity has been broadly used in fluid and plasma physics, this quantity has been underutilized in space physics due to low time resolution observations. We report Magnetospheric Multiscale (MMS) observations of enhanced electron vorticity in the vicinity of the electron diffusion region of magnetic reconnection. On 11 July 2017 MMS traversed the magnetotail current sheet, observing tailward-to-earthward outflow reversal, current-carrying electron jets in the direction along the electron meandering motion or out-of-plane direction, agyrotropic electron distribution functions, and dissipative signatures. At the edge of the electron jets, the electron vorticity increased with magnitudes greater than the electron gyrofrequency. The out-of-plane velocity shear along distance from the current sheet leads to the enhanced vorticity. This, in turn, contributes to the magnetic field perturbations observed by MMS. These observations indicate that electron vorticity can act as a proxy for delineating the electron diffusion region of magnetic reconnection.
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Affiliation(s)
- K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
| | - E. Choi
- Southwest Research InstituteSan AntonioTXUSA
| | - K. Dokgo
- Southwest Research InstituteSan AntonioTXUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - M. L. Goldstein
- The Goddard Planetary Heliophysics InstituteUniversity of MarylandBaltimoreMDUSA
| | | | | | - Q. Q. Shi
- School of Earth and Space SciencesPeking UniversityPekingChina
| | - H. Fu
- School of Science and EnvironmentBeihang UniversityBeijingChina
| | - H. Hasegawa
- Institute of Space and Astronautical ScienceJapan Aerospace Exploration AgencySagamiharaJapan
| | | | | | - R. B. Torbert
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | | | - L. Avanov
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- The Goddard Planetary Heliophysics InstituteUniversity of MarylandBaltimoreMDUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
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10
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Vines SK, Allen RC, Anderson BJ, Engebretson MJ, Fuselier SA, Russell CT, Strangeway RJ, Ergun RE, Lindqvist PA, Torbert RB, Burch JL. EMIC Waves in the Outer Magnetosphere: Observations of an Off-Equator Source Region. Geophys Res Lett 2019; 46:5707-5716. [PMID: 31423036 PMCID: PMC6686711 DOI: 10.1029/2019gl082152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/03/2019] [Accepted: 05/10/2019] [Indexed: 06/10/2023]
Abstract
Electromagnetic ion cyclotron (EMIC) waves at large L shells were observed away from the magnetic equator by the Magnetospheric MultiScale (MMS) mission nearly continuously for over four hours on 28 October 2015. During this event, the wave Poynting vector direction systematically changed from parallel to the magnetic field (toward the equator), to bidirectional, to antiparallel (away from the equator). These changes coincide with the shift in the location of the minimum in the magnetic field in the southern hemisphere from poleward to equatorward of MMS. The local plasma conditions measured with the EMIC waves also suggest that the outer magnetospheric region sampled during this event was generally unstable to EMIC wave growth. Together, these observations indicate that the bidirectionally propagating wave packets were not a result of reflection at high latitudes but that MMS passed through an off-equator EMIC wave source region associated with the local minimum in the magnetic field.
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Affiliation(s)
- S. K. Vines
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - R. C. Allen
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - B. J. Anderson
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | | | - S. A. Fuselier
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
- Institute for Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
- Institute for Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCAUSA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado at BoulderBoulderCOUSA
| | - P. A. Lindqvist
- Department of Space and Plasma PhysicsRoyal Institute of TechnologyStockholmSweden
| | - R. B. Torbert
- Southwest Research InstituteSan AntonioTXUSA
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
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11
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Phan TD, Eastwood JP, Shay MA, Drake JF, Sonnerup BUÖ, Fujimoto M, Cassak PA, Øieroset M, Burch JL, Torbert RB, Rager AC, Dorelli JC, Gershman DJ, Pollock C, Pyakurel PS, Haggerty CC, Khotyaintsev Y, Lavraud B, Saito Y, Oka M, Ergun RE, Retino A, Le Contel O, Argall MR, Giles BL, Moore TE, Wilder FD, Strangeway RJ, Russell CT, Lindqvist PA, Magnes W. Publisher Correction: Electron magnetic reconnection without ion coupling in Earth's turbulent magnetosheath. Nature 2019; 569:E9. [PMID: 31073227 DOI: 10.1038/s41586-019-1208-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Change history: In this Letter, the y-axis values in Fig. 3f should go from 4 to -8 (rather than from 4 to -4), the y-axis values in Fig. 3h should appear next to the major tick marks (rather than the minor ticks), and in Fig. 1b, the arrows at the top and bottom of the electron-scale current sheet were going in the wrong direction; these errors have been corrected online.
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Affiliation(s)
- T D Phan
- Space Sciences Laboratory, University of California, Berkeley, CA, USA.
| | - J P Eastwood
- The Blackett Laboratory, Imperial College London, London, UK
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | - J F Drake
- University of Maryland, College Park, MD, USA
| | | | | | - P A Cassak
- West Virginia University, Morgantown, WV, USA
| | - M Øieroset
- Space Sciences Laboratory, University of California, Berkeley, CA, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
| | - R B Torbert
- University of New Hampshire, Durham, NH, USA
| | - A C Rager
- Catholic University of America, Washington, DC, USA.,NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | | | | | | | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, Toulouse, France
| | - Y Saito
- ISAS/JAXA, Sagamihara, Japan
| | - M Oka
- Space Sciences Laboratory, University of California, Berkeley, CA, USA
| | - R E Ergun
- University of Colorado LASP, Boulder, CO, USA
| | - A Retino
- CNRS/Ecole Polytechnique, Paris, France
| | | | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - F D Wilder
- University of Colorado LASP, Boulder, CO, USA
| | - R J Strangeway
- University of California, Los Angeles, Los Angeles, CA, USA
| | - C T Russell
- University of California, Los Angeles, Los Angeles, CA, USA
| | | | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
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12
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Parashar TN, Chasapis A, Bandyopadhyay R, Chhiber R, Matthaeus WH, Maruca B, Shay MA, Burch JL, Moore TE, Giles BL, Gershman DJ, Pollock CJ, Torbert RB, Russell CT, Strangeway RJ, Roytershteyn V. Kinetic Range Spectral Features of Cross Helicity Using the Magnetospheric Multiscale Spacecraft. Phys Rev Lett 2018; 121:265101. [PMID: 30636132 DOI: 10.1103/physrevlett.121.265101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/21/2018] [Indexed: 06/09/2023]
Abstract
We study spectral features of ion velocity and magnetic field correlations in the magnetosheath and in the solar wind using data from the Magnetospheric Multiscale (MMS) spacecraft. High-resolution MMS observations enable the study of the transition of these correlations between their magnetofluid character at larger scales into the subproton kinetic range, previously unstudied in spacecraft data. Cross-helicity, angular alignment, and energy partitioning is examined over a suitable range of scales, employing measurements based on the Taylor frozen-in approximation as well as direct two-spacecraft correlation measurements. The results demonstrate signatures of alignment at large scales. As kinetic scales are approached, the alignment between v and b is destroyed by demagnetization of protons.
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Affiliation(s)
- Tulasi N Parashar
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - Alexandros Chasapis
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - Riddhi Bandyopadhyay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - Rohit Chhiber
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - W H Matthaeus
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - B Maruca
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - M A Shay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - J L Burch
- Southwest Research Institute, San Antonio 78238-5166, Texas, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - C J Pollock
- Denali Scientific, Fairbanks 99709, Alaska, USA
| | - R B Torbert
- University of New Hampshire, Durham 03824, New Hampshire, USA
| | - C T Russell
- University of California, Los Angeles 90095-1567, California, USA
| | - R J Strangeway
- University of California, Los Angeles 90095-1567, California, USA
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13
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Torbert RB, Burch JL, Phan TD, Hesse M, Argall MR, Shuster J, Ergun RE, Alm L, Nakamura R, Genestreti KJ, Gershman DJ, Paterson WR, Turner DL, Cohen I, Giles BL, Pollock CJ, Wang S, Chen LJ, Stawarz JE, Eastwood JP, Hwang KJ, Farrugia C, Dors I, Vaith H, Mouikis C, Ardakani A, Mauk BH, Fuselier SA, Russell CT, Strangeway RJ, Moore TE, Drake JF, Shay MA, Khotyaintsev YV, Lindqvist PA, Baumjohann W, Wilder FD, Ahmadi N, Dorelli JC, Avanov LA, Oka M, Baker DN, Fennell JF, Blake JB, Jaynes AN, Le Contel O, Petrinec SM, Lavraud B, Saito Y. Electron-scale dynamics of the diffusion region during symmetric magnetic reconnection in space. Science 2018; 362:1391-1395. [PMID: 30442767 DOI: 10.1126/science.aat2998] [Citation(s) in RCA: 158] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 11/06/2018] [Indexed: 11/02/2022]
Abstract
Magnetic reconnection is an energy conversion process that occurs in many astrophysical contexts including Earth's magnetosphere, where the process can be investigated in situ by spacecraft. On 11 July 2017, the four Magnetospheric Multiscale spacecraft encountered a reconnection site in Earth's magnetotail, where reconnection involves symmetric inflow conditions. The electron-scale plasma measurements revealed (i) super-Alfvénic electron jets reaching 15,000 kilometers per second; (ii) electron meandering motion and acceleration by the electric field, producing multiple crescent-shaped structures in the velocity distributions; and (iii) the spatial dimensions of the electron diffusion region with an aspect ratio of 0.1 to 0.2, consistent with fast reconnection. The well-structured multiple layers of electron populations indicate that the dominant electron dynamics are mostly laminar, despite the presence of turbulence near the reconnection site.
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Affiliation(s)
- R B Torbert
- University of New Hampshire, Durham, NH, USA. .,Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - T D Phan
- University of California, Berkeley, CA, USA
| | - M Hesse
- Southwest Research Institute (SwRI), San Antonio, TX, USA.,University of Bergen, Bergen, Norway
| | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - J Shuster
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - R E Ergun
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - L Alm
- Swedish Institute of Space Physics, Uppsala, Sweden
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - K J Genestreti
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - D L Turner
- Aerospace Corporation, El Segundo, CA, USA
| | - I Cohen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - C J Pollock
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - S Wang
- University of Maryland, College Park, MD, USA
| | - L-J Chen
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,University of Maryland, College Park, MD, USA
| | - J E Stawarz
- Blackett Laboratory, Imperial College London, London, UK
| | - J P Eastwood
- Blackett Laboratory, Imperial College London, London, UK
| | - K J Hwang
- Southwest Research Institute (SwRI), San Antonio, TX, USA
| | - C Farrugia
- University of New Hampshire, Durham, NH, USA
| | - I Dors
- University of New Hampshire, Durham, NH, USA
| | - H Vaith
- University of New Hampshire, Durham, NH, USA
| | - C Mouikis
- University of New Hampshire, Durham, NH, USA
| | - A Ardakani
- University of New Hampshire, Durham, NH, USA
| | - B H Mauk
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - S A Fuselier
- Southwest Research Institute (SwRI), San Antonio, TX, USA.,University of Texas, San Antonio, TX, USA
| | - C T Russell
- University of California, Los Angeles, CA, USA
| | | | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - J F Drake
- University of Maryland, College Park, MD, USA
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | | | | | - W Baumjohann
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - F D Wilder
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - N Ahmadi
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - L A Avanov
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - M Oka
- University of California, Berkeley, CA, USA
| | - D N Baker
- University of Colorado Laboratory for Atmospheric and Space Physics, Boulder, CO, USA
| | | | - J B Blake
- Aerospace Corporation, El Segundo, CA, USA
| | | | - O Le Contel
- Laboratoire de Physique des Plasmas, CNRS/Ecole Polytechnique/Sorbonne Université/Univ. Paris Sud/Observatoire de Paris, Paris, France
| | - S M Petrinec
- Lockheed Martin Advanced Technology Center, Palo Alto, CA, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, CNRS, Centre National d'Etudes Spatiales, Université de Toulouse, Toulouse, France
| | - Y Saito
- Institute for Space and Astronautical Sciences, Sagamihara, Japan
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14
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Turner DL, Wilson LB, Liu TZ, Cohen IJ, Schwartz SJ, Osmane A, Fennell JF, Clemmons JH, Blake JB, Westlake J, Mauk BH, Jaynes AN, Leonard T, Baker DN, Strangeway RJ, Russell CT, Gershman DJ, Avanov L, Giles BL, Torbert RB, Broll J, Gomez RG, Fuselier SA, Burch JL. Autogenous and efficient acceleration of energetic ions upstream of Earth's bow shock. Nature 2018; 561:206-210. [PMID: 30209369 DOI: 10.1038/s41586-018-0472-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/06/2018] [Indexed: 11/09/2022]
Abstract
Earth and its magnetosphere are immersed in the supersonic flow of the solar-wind plasma that fills interplanetary space. As the solar wind slows and deflects to flow around Earth, or any other obstacle, a 'bow shock' forms within the flow. Under almost all solar-wind conditions, planetary bow shocks such as Earth's are collisionless, supercritical shocks, meaning that they reflect and accelerate a fraction of the incident solar-wind ions as an energy dissipation mechanism1,2, which results in the formation of a region called the ion foreshock3. In the foreshock, large-scale, transient phenomena can develop, such as 'hot flow anomalies'4-9, which are concentrations of shock-reflected, suprathermal ions that are channelled and accumulated along certain structures in the upstream magnetic field. Hot flow anomalies evolve explosively, often resulting in the formation of new shocks along their upstream edges5,10, and potentially contribute to particle acceleration11-13, but there have hitherto been no observations to constrain this acceleration or to confirm the underlying mechanism. Here we report observations of a hot flow anomaly accelerating solar-wind ions from roughly 1-10 kiloelectronvolts up to almost 1,000 kiloelectronvolts. The acceleration mechanism depends on the mass and charge state of the ions and is consistent with first-order Fermi acceleration14,15. The acceleration that we observe results from only the interaction of Earth's bow shock with the solar wind, but produces a much, much larger number of energetic particles compared to what would typically be produced in the foreshock from acceleration at the bow shock. Such autogenous and efficient acceleration at quasi-parallel bow shocks (the normal direction of which are within about 45 degrees of the interplanetary magnetic field direction) provides a potential solution to Fermi's 'injection problem', which requires an as-yet-unexplained seed population of energetic particles, and implies that foreshock transients may be important in the generation of cosmic rays at astrophysical shocks throughout the cosmos.
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Affiliation(s)
- D L Turner
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA.
| | - L B Wilson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - T Z Liu
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - I J Cohen
- Applied Physics Laboratory, Laurel, MD, USA
| | | | - A Osmane
- School of Electrical Engineering, Aalto University, Espoo, Finland.,Rudolf Peierls Centre of Theoretical Physics, University of Oxford, Oxford, UK
| | - J F Fennell
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - J H Clemmons
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - J B Blake
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - J Westlake
- Applied Physics Laboratory, Laurel, MD, USA
| | - B H Mauk
- Applied Physics Laboratory, Laurel, MD, USA
| | - A N Jaynes
- Department of Physics and Astronomy, University of Iowa, Iowa City, IA, USA
| | - T Leonard
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA
| | - D N Baker
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA
| | - R J Strangeway
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - C T Russell
- Department of Earth, Planetary, and Space Science, University of California, Los Angeles, CA, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - L Avanov
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - R B Torbert
- Institute For the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH, USA.,Southwest Research Institute, San Antonio, TX, USA
| | - J Broll
- Southwest Research Institute, San Antonio, TX, USA.,Departoment of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA
| | - R G Gomez
- Space Sciences Department, The Aerospace Corporation, El Segundo, CA, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, TX, USA.,Departoment of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
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15
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Kitamura N, Kitahara M, Shoji M, Miyoshi Y, Hasegawa H, Nakamura S, Katoh Y, Saito Y, Yokota S, Gershman DJ, Vinas AF, Giles BL, Moore TE, Paterson WR, Pollock CJ, Russell CT, Strangeway RJ, Fuselier SA, Burch JL. Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma. Science 2018; 361:1000-1003. [PMID: 30190400 DOI: 10.1126/science.aap8730] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 07/04/2018] [Indexed: 11/02/2022]
Abstract
Particle acceleration by plasma waves and spontaneous wave generation are fundamental energy and momentum exchange processes in collisionless plasmas. Such wave-particle interactions occur ubiquitously in space. We present ultrafast measurements in Earth's magnetosphere by the Magnetospheric Multiscale spacecraft that enabled quantitative evaluation of energy transfer in interactions associated with electromagnetic ion cyclotron waves. The observed ion distributions are not symmetric around the magnetic field direction but are in phase with the plasma wave fields. The wave-ion phase relations demonstrate that a cyclotron resonance transferred energy from hot protons to waves, which in turn nonresonantly accelerated cold He+ to energies up to ~2 kilo-electron volts. These observations provide direct quantitative evidence for collisionless energy transfer in plasmas between distinct particle populations via wave-particle interactions.
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Affiliation(s)
- N Kitamura
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan. .,Department of Earth and Planetary Science, Graduate School of Science, the University of Tokyo, Tokyo, Japan
| | - M Kitahara
- Department of Geophysics, Graduate School of Science, Tohoku University, Sendai, Japan
| | - M Shoji
- Institute for Space-Earth Environmental Research (ISEE), Nagoya University, Nagoya, Japan
| | - Y Miyoshi
- Institute for Space-Earth Environmental Research (ISEE), Nagoya University, Nagoya, Japan
| | - H Hasegawa
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - S Nakamura
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Uji, Japan
| | - Y Katoh
- Department of Geophysics, Graduate School of Science, Tohoku University, Sendai, Japan
| | - Y Saito
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Japan
| | - S Yokota
- Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - A F Vinas
- NASA Goddard Space Flight Center, Greenbelt, MD, USA.,Department of Physics, American University, Washington, DC, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | | - C T Russell
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA, USA
| | - R J Strangeway
- Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, TX, USA.,University of Texas at San Antonio, San Antonio, TX, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX, USA
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16
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Eastwood JP, Mistry R, Phan TD, Schwartz SJ, Ergun RE, Drake JF, Øieroset M, Stawarz JE, Goldman MV, Haggerty C, Shay MA, Burch JL, Gershman DJ, Giles BL, Lindqvist PA, Torbert RB, Strangeway RJ, Russell CT. Guide Field Reconnection: Exhaust Structure and Heating. Geophys Res Lett 2018; 45:4569-4577. [PMID: 31031447 PMCID: PMC6473590 DOI: 10.1029/2018gl077670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/11/2018] [Accepted: 04/14/2018] [Indexed: 06/09/2023]
Abstract
Magnetospheric Multiscale observations are used to probe the structure and temperature profile of a guide field reconnection exhaust ~100 ion inertial lengths downstream from the X-line in the Earth's magnetosheath. Asymmetric Hall electric and magnetic field signatures were detected, together with a density cavity confined near 1 edge of the exhaust and containing electron flow toward the X-line. Electron holes were also detected both on the cavity edge and at the Hall magnetic field reversal. Predominantly parallel ion and electron heating was observed in the main exhaust, but within the cavity, electron cooling and enhanced parallel ion heating were found. This is explained in terms of the parallel electric field, which inhibits electron mixing within the cavity on newly reconnected field lines but accelerates ions. Consequently, guide field reconnection causes inhomogeneous changes in ion and electron temperature across the exhaust.
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Affiliation(s)
| | - R. Mistry
- The Blackett LaboratoryImperial College LondonLondonUK
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - S. J. Schwartz
- The Blackett LaboratoryImperial College LondonLondonUK
- LASP/Department of Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - R. E. Ergun
- LASP/Department of Astrophysical and Planetary SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - J. F. Drake
- Department of Physics and Institute for Physical Science and TechnologyUniversity of MarylandCollege ParkMDUSA
| | - M. Øieroset
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - J. E. Stawarz
- The Blackett LaboratoryImperial College LondonLondonUK
| | - M. V. Goldman
- Department of PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - C. Haggerty
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
- Now at The Department of Astronomy and AstrophysicsUniversity of ChicagoChicagoILUSA
| | - M. A. Shay
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - D. J. Gershman
- Department of Physics and AstronomyUniversity of DelawareNewarkDEUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - B. L. Giles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - P. A. Lindqvist
- Department of Space and Plasma PhysicsRoyal Institute of TechnologyStockholmSweden
| | - R. B. Torbert
- Now at The Department of Astronomy and AstrophysicsUniversity of ChicagoChicagoILUSA
- Space Science CenterUniversity of New HampshireDurhamNHUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
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17
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Burch JL, Webster JM, Genestreti KJ, Torbert RB, Giles BL, Fuselier SA, Dorelli JC, Rager AC, Phan TD, Allen RC, Chen L, Wang S, Le Contel O, Russell CT, Strangeway RJ, Ergun RE, Jaynes AN, Lindqvist P, Graham DB, Wilder FD, Hwang K, Goldstein J. Wave Phenomena and Beam-Plasma Interactions at the Magnetopause Reconnection Region. J Geophys Res Space Phys 2018; 123:1118-1133. [PMID: 29938153 PMCID: PMC5993346 DOI: 10.1002/2017ja024789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 12/28/2017] [Accepted: 01/10/2018] [Indexed: 06/08/2023]
Abstract
This paper reports on Magnetospheric Multiscale observations of whistler mode chorus and higher-frequency electrostatic waves near and within a reconnection diffusion region on 23 November 2016. The diffusion region is bounded by crescent-shaped electron distributions and associated dissipation just upstream of the X-line and by magnetic field-aligned currents and electric fields leading to dissipation near the electron stagnation point. Measurements were made southward of the X-line as determined by southward directed ion and electron jets. We show that electrostatic wave generation is due to magnetosheath electron beams formed by the electron jets as they interact with a cold background plasma and more energetic population of magnetospheric electrons. On the magnetosphere side of the X-line the electron beams are accompanied by a strong perpendicular electron temperature anisotropy, which is shown to be the source of an observed rising-tone whistler mode chorus event. We show that the apex of the chorus event and the onset of electrostatic waves coincide with the opening of magnetic field lines at the electron stagnation point.
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Affiliation(s)
- J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | - J. M. Webster
- Department of Physics and AstronomyRice UniversityHoustonTXUSA
| | | | - R. B. Torbert
- Southwest Research InstituteSan AntonioTXUSA
- Department of PhysicsUniversity of New HampshireDurhamNHUSA
| | - B. L. Giles
- NASA, Goddard Space Flight CenterGreenbeltMDUSA
| | | | | | - A. C. Rager
- NASA, Goddard Space Flight CenterGreenbeltMDUSA
- Department of PhysicsCatholic University of AmericaWashingtonDCUSA
| | - T. D. Phan
- Space Sciences LaboratoryUniversity of CaliforniaBerkeleyCAUSA
| | - R. C. Allen
- Applied Physics LaboratoryThe Johns Hopkins UniversityLaurelMDUSA
| | - L.‐J. Chen
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - S. Wang
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - O. Le Contel
- Laboratoire de Physique des PlasmasCNRS, Ecole Polytechnique, UPMC University Paris 06, Université Paris‐Sud, Observatoire de ParisParisFrance
| | - C. T. Russell
- Earth and Planetary SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. J. Strangeway
- Earth and Planetary SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - R. E. Ergun
- LASPUniversity of Colorado BoulderBoulderCOUSA
| | - A. N. Jaynes
- Department of Physics and AstronomyUniversity of IowaIowa CityIAUSA
| | | | | | | | - K.‐J. Hwang
- Southwest Research InstituteSan AntonioTXUSA
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18
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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. Geophys Res Lett 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] [What about the content of this article? (0)] [Affiliation(s)] [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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19
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Varsani A, Nakamura R, Sergeev VA, Baumjohann W, Owen CJ, Petrukovich AA, Yao Z, Nakamura TKM, Kubyshkina MV, Sotirelis T, Burch JL, Genestreti KJ, Vörös Z, Andriopoulou M, Gershman DJ, Avanov LA, Magnes W, Russell CT, Plaschke F, Khotyaintsev YV, Giles BL, Coffey VN, Dorelli JC, Strangeway RJ, Torbert RB, Lindqvist P, Ergun R. Simultaneous Remote Observations of Intense Reconnection Effects by DMSP and MMS Spacecraft During a Storm Time Substorm. J Geophys Res Space Phys 2017; 122:10891-10909. [PMID: 29399431 PMCID: PMC5784414 DOI: 10.1002/2017ja024547] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/27/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
During a magnetic storm on 23 June 2015, several very intense substorms took place, with signatures observed by multiple spacecraft including DMSP and Magnetospheric Multiscale (MMS). At the time of interest, DMSP F18 crossed inbound through a poleward expanding auroral bulge boundary at 23.5 h magnetic local time (MLT), while MMS was located duskward of 22 h MLT during an inward crossing of the expanding plasma sheet boundary. The two spacecraft observed a consistent set of signatures as they simultaneously crossed the reconnection separatrix layer during this very intense reconnection event. These include (1) energy dispersion of the energetic ions and electrons traveling earthward, accompanied with high electron energies in the vicinity of the separatrix; (2) energy dispersion of polar rain electrons, with a high-energy cutoff; and (3) intense inward convection of the magnetic field lines at the MMS location. The high temporal resolution measurements by MMS provide unprecedented observations of the outermost electron boundary layer. We discuss the relevance of the energy dispersion of the electrons, and their pitch angle distribution, to the spatial and temporal evolution of the boundary layer. The results indicate that the underlying magnetotail magnetic reconnection process was an intrinsically impulsive and the active X-line was located relatively close to the Earth, approximately at 16-18 RE.
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Affiliation(s)
- A. Varsani
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - V. A. Sergeev
- Earth's Physics DepartmentSt. Petersburg State UniversitySt. PetersburgRussia
| | - W. Baumjohann
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - C. J. Owen
- Mullard Space Science Laboratory/UCLDorkingUK
| | | | - Z. Yao
- Space Science Technologies and Astrophysics Research InstituteLiegeBelgium
| | | | - M. V. Kubyshkina
- Earth's Physics DepartmentSt. Petersburg State UniversitySt. PetersburgRussia
| | - T. Sotirelis
- Applied Physics LaboratoryThe Johns Hopkins UniversityBaltimoreMAUSA
| | - J. L. Burch
- Southwest Research InstituteSan AntonioTXUSA
| | | | - Z. Vörös
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- Institute of PhysicsUniversity of GrazGrazAustria
| | - M. Andriopoulou
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - D. J. Gershman
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - L. A. Avanov
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - W. Magnes
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - C. T. Russell
- University of California Los Angeles, IGPP/EPSSLos AngelesCAUSA
| | - F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | | | - B. L. Giles
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - V. N. Coffey
- NASA Marshall Space Flight CenterHuntsvilleALUSA
| | - J. C. Dorelli
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - R. B. Torbert
- Southwest Research InstituteSan AntonioTXUSA
- University of New HampshireDurhamNHUSA
| | | | - R. Ergun
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
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20
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Zhou M, Berchem J, Walker RJ, El-Alaoui M, Deng X, Cazzola E, Lapenta G, Goldstein ML, Paterson WR, Pang Y, Ergun RE, Lavraud B, Liang H, Russell CT, Strangeway RJ, Zhao C, Giles BL, Pollock CJ, Lindqvist PA, Marklund G, Wilder FD, Khotyaintsev YV, Torbert RB, Burch JL. Coalescence of Macroscopic Flux Ropes at the Subsolar Magnetopause: Magnetospheric Multiscale Observations. Phys Rev Lett 2017; 119:055101. [PMID: 28949734 DOI: 10.1103/physrevlett.119.055101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Indexed: 06/07/2023]
Abstract
We report unambiguous in situ observation of the coalescence of macroscopic flux ropes by the magnetospheric multiscale (MMS) mission. Two coalescing flux ropes with sizes of ∼1 R_{E} were identified at the subsolar magnetopause by the occurrence of an asymmetric quadrupolar signature in the normal component of the magnetic field measured by the MMS spacecraft. An electron diffusion region (EDR) with a width of four local electron inertial lengths was embedded within the merging current sheet. The EDR was characterized by an intense parallel electric field, significant energy dissipation, and suprathermal electrons. Although the electrons were organized by a large guide field, the small observed electron pressure nongyrotropy may be sufficient to support a significant fraction of the parallel electric field within the EDR. Since the flux ropes are observed in the exhaust region, we suggest that secondary EDRs are formed further downstream of the primary reconnection line between the magnetosheath and magnetospheric fields.
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Affiliation(s)
- M Zhou
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - J Berchem
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - R J Walker
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - M El-Alaoui
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - X Deng
- Nanchang University, Nanchang 330031, People's Republic of China
| | - E Cazzola
- Centre for Plasma Astrophysics, Department of Mathematics, Katholieke Universiteit, Leuven 3001, Belgium
| | - G Lapenta
- Centre for Plasma Astrophysics, Department of Mathematics, Katholieke Universiteit, Leuven 3001, Belgium
| | - M L Goldstein
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
- Space Science Institute, Boulder 80301, Colorado, USA
| | - W R Paterson
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - Y Pang
- Nanchang University, Nanchang 330031, People's Republic of China
| | - R E Ergun
- University of Colorado LASP, Boulder 80303, Colorado, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, UPS, CNES, Toulouse 31028, France
| | - H Liang
- Department of Physics and Astronomy, UCLA, Los Angeles 90095, California, USA
| | - C T Russell
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - R J Strangeway
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - C Zhao
- Department of Earth, Planetary, and Space Sciences, UCLA, Los Angeles 90095, California, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt 20771, Maryland, USA
| | - P-A Lindqvist
- Royal Institute of Technology, Stockholm SE-11428, Sweden
| | - G Marklund
- Royal Institute of Technology, Stockholm SE-11428, Sweden
| | - F D Wilder
- University of Colorado LASP, Boulder 80303, Colorado, USA
| | | | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - J L Burch
- Southwest Research Institute, San Antonio Texas 78238, USA
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21
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Wilder FD, Ergun RE, Eriksson S, Phan TD, Burch JL, Ahmadi N, Goodrich KA, Newman DL, Trattner KJ, Torbert RB, Giles BL, Strangeway RJ, Magnes W, Lindqvist PA, Khotyaintsev YV. Multipoint Measurements of the Electron Jet of Symmetric Magnetic Reconnection with a Moderate Guide Field. Phys Rev Lett 2017; 118:265101. [PMID: 28707935 DOI: 10.1103/physrevlett.118.265101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Indexed: 06/07/2023]
Abstract
We report observations from the Magnetospheric Multiscale (MMS) satellites of the electron jet in a symmetric magnetic reconnection event with moderate guide field. All four spacecraft sampled the ion diffusion region and observed the electron exhaust. The observations suggest that the presence of the guide field leads to an asymmetric Hall field, which results in an electron jet skewed towards the separatrix with a nonzero component along the magnetic field. The jet appears in conjunction with a spatially and temporally persistent parallel electric field ranging from -3 to -5 mV/m, which led to dissipation on the order of 8 nW/m^{3}. The parallel electric field heats electrons that drift through it, and is associated with a streaming instability and electron phase space holes.
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Affiliation(s)
- F D Wilder
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - R E Ergun
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S Eriksson
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - N Ahmadi
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - K A Goodrich
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D L Newman
- Department of Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - K J Trattner
- Laboratory of Atmospheric and Space Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - R B Torbert
- Department of Physics, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - R J Strangeway
- Department of Earth and Space Sciences, University of California Los Angeles, Los Angeles, California 90095, USA
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - P-A Lindqvist
- Royal Institute of Technology, Stockholm SE-11428, Sweden
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22
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Russell CT, Strangeway RJ, Zhao C, Anderson BJ, Baumjohann W, Bromund KR, Fischer D, Kepko L, Le G, Magnes W, Nakamura R, Plaschke F, Slavin JA, Torbert RB, Moore TE, Paterson WR, Pollock CJ, Burch JL. Structure, force balance, and topology of Earth's magnetopause. Science 2017; 356:960-963. [PMID: 28572393 DOI: 10.1126/science.aag3112] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 01/25/2017] [Accepted: 05/12/2017] [Indexed: 11/02/2022]
Abstract
The magnetopause deflects the solar wind plasma and confines Earth's magnetic field. We combine measurements made by the four spacecraft of the Magnetospheric Multiscale mission to demonstrate how the plasma and magnetic forces at the boundary affect the interaction between the shocked solar wind and Earth's magnetosphere. We compare these forces with the plasma pressure and examine the electron distribution function. We find that the magnetopause has sublayers with thickness comparable to the ion scale. Small pockets of low magnetic field strength, small radius of curvature, and high electric current mark the electron diffusion region. The flow of electrons, parallel and antiparallel to the magnetic field, reveals a complex topology with the creation of magnetic ropes at the boundary.
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Affiliation(s)
- C T Russell
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA.
| | - R J Strangeway
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - C Zhao
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - B J Anderson
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA
| | - W Baumjohann
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - K R Bromund
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - D Fischer
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - L Kepko
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.,University of New Hampshire, Durham, NH 03824, USA
| | - G Le
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8010 Graz, Austria
| | - J A Slavin
- Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109-2143, USA
| | - R B Torbert
- University of New Hampshire, Durham, NH 03824, USA
| | - T E Moore
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - W R Paterson
- Earth Planetary and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - C J Pollock
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, TX 78228-0510, USA
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23
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Le G, Chi PJ, Strangeway RJ, Russell CT, Slavin JA, Takahashi K, Singer HJ, Anderson BJ, Bromund K, Fischer D, Kepko EL, Magnes W, Nakamura R, Plaschke F, Torbert RB. Global observations of magnetospheric high- m poloidal waves during the 22 June 2015 magnetic storm. Geophys Res Lett 2017; 44:3456-3464. [PMID: 28713180 PMCID: PMC5488625 DOI: 10.1002/2017gl073048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 04/06/2017] [Accepted: 04/06/2017] [Indexed: 06/07/2023]
Abstract
We report global observations of high-m poloidal waves during the recovery phase of the 22 June 2015 magnetic storm from a constellation of widely spaced satellites of five missions including Magnetospheric Multiscale (MMS), Van Allen Probes, Time History of Events and Macroscale Interactions during Substorm (THEMIS), Cluster, and Geostationary Operational Environmental Satellites (GOES). The combined observations demonstrate the global spatial extent of storm time poloidal waves. MMS observations confirm high azimuthal wave numbers (m ~ 100). Mode identification indicates the waves are associated with the second harmonic of field line resonances. The wave frequencies exhibit a decreasing trend as L increases, distinguishing them from the single-frequency global poloidal modes normally observed during quiet times. Detailed examination of the instantaneous frequency reveals discrete spatial structures with step-like frequency changes along L. Each discrete L shell has a steady wave frequency and spans about 1 RE , suggesting that there exist a discrete number of drift-bounce resonance regions across L shells during storm times.
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Affiliation(s)
- G. Le
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - P. J. Chi
- Department of Earth, Planetary, and Space Sciences and Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. J. Strangeway
- Department of Earth, Planetary, and Space Sciences and Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - C. T. Russell
- Department of Earth, Planetary, and Space Sciences and Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - J. A. Slavin
- Department of Climate and Space Sciences & EngineeringUniversity of MichiganAnn ArborMichiganUSA
| | - K. Takahashi
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - H. J. Singer
- NOAA Space Weather Prediction CenterBoulderColoradoUSA
| | - B. J. Anderson
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - K. Bromund
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - D. Fischer
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - E. L. Kepko
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - W. Magnes
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - R. Nakamura
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - F. Plaschke
- Space Research Institute, Austrian Academy of SciencesGrazAustria
| | - R. B. Torbert
- Physics DepartmentUniversity of New HampshireDurhamNew HampshireUSA
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24
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Johlander A, Schwartz SJ, Vaivads A, Khotyaintsev YV, Gingell I, Peng IB, Markidis S, Lindqvist PA, Ergun RE, Marklund GT, Plaschke F, Magnes W, Strangeway RJ, Russell CT, Wei H, Torbert RB, Paterson WR, Gershman DJ, Dorelli JC, Avanov LA, Lavraud B, Saito Y, Giles BL, Pollock CJ, Burch JL. Rippled Quasiperpendicular Shock Observed by the Magnetospheric Multiscale Spacecraft. Phys Rev Lett 2016; 117:165101. [PMID: 27792387 DOI: 10.1103/physrevlett.117.165101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Indexed: 06/06/2023]
Abstract
Collisionless shock nonstationarity arising from microscale physics influences shock structure and particle acceleration mechanisms. Nonstationarity has been difficult to quantify due to the small spatial and temporal scales. We use the closely spaced (subgyroscale), high-time-resolution measurements from one rapid crossing of Earth's quasiperpendicular bow shock by the Magnetospheric Multiscale (MMS) spacecraft to compare competing nonstationarity processes. Using MMS's high-cadence kinetic plasma measurements, we show that the shock exhibits nonstationarity in the form of ripples.
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Affiliation(s)
- A Johlander
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
- Department of Physics and Astronomy, Uppsala University, Uppsala 75120, Sweden
| | - S J Schwartz
- Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - A Vaivads
- Swedish Institute of Space Physics, Uppsala 75121, Sweden
| | | | - I Gingell
- Blackett Laboratory, Imperial College London, London SW7 2AZ, United Kingdom
| | - I B Peng
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - S Markidis
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - P-A Lindqvist
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - R E Ergun
- Laboratory of Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - G T Marklund
- KTH Royal Institute of Technology, Stockholm 11428, Sweden
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz 8042, Austria
| | - R J Strangeway
- University of California, Los Angeles, California 90095, USA
| | - C T Russell
- University of California, Los Angeles, California 90095, USA
| | - H Wei
- University of California, Los Angeles, California 90095, USA
| | - R B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - W R Paterson
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - D J Gershman
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
- University of Maryland, College Park, Maryland 20742, USA
| | - J C Dorelli
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - L A Avanov
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, Toulouse 31028, France
- Centre National de la Recherche Scientifique, UMR 5277, Toulouse 31400, France
| | - Y Saito
- Institute of Space and Astronautical Science, JAXA, Sagamihara 2525210, Japan
| | - B L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - C J Pollock
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238, USA
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25
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Eriksson S, Wilder FD, Ergun RE, Schwartz SJ, Cassak PA, Burch JL, Chen LJ, Torbert RB, Phan TD, Lavraud B, Goodrich KA, Holmes JC, Stawarz JE, Sturner AP, Malaspina DM, Usanova ME, Trattner KJ, Strangeway RJ, Russell CT, Pollock CJ, Giles BL, Hesse M, Lindqvist PA, Drake JF, Shay MA, Nakamura R, Marklund GT. Magnetospheric Multiscale Observations of the Electron Diffusion Region of Large Guide Field Magnetic Reconnection. Phys Rev Lett 2016; 117:015001. [PMID: 27419573 DOI: 10.1103/physrevlett.117.015001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Indexed: 06/06/2023]
Abstract
We report observations from the Magnetospheric Multiscale (MMS) satellites of a large guide field magnetic reconnection event. The observations suggest that two of the four MMS spacecraft sampled the electron diffusion region, whereas the other two spacecraft detected the exhaust jet from the event. The guide magnetic field amplitude is approximately 4 times that of the reconnecting field. The event is accompanied by a significant parallel electric field (E_{∥}) that is larger than predicted by simulations. The high-speed (∼300 km/s) crossing of the electron diffusion region limited the data set to one complete electron distribution inside of the electron diffusion region, which shows significant parallel heating. The data suggest that E_{∥} is balanced by a combination of electron inertia and a parallel gradient of the gyrotropic electron pressure.
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Affiliation(s)
- S Eriksson
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - F D Wilder
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - R E Ergun
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - S J Schwartz
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- The Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom
| | - P A Cassak
- West Virginia University, Morgantown, West Virginia 26506, USA
| | - J L Burch
- Southwest Research Institute, San Antonio, Texas 78238-5166, USA
| | - L-J Chen
- University of Maryland, College Park, Maryland 20742, USA
| | - R B Torbert
- Southwest Research Institute, San Antonio, Texas 78238-5166, USA
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - T D Phan
- Space Sciences Laboratory, University of California, Berkeley, California 94720, USA
| | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, 31028 Toulouse, France
- Centre National de la Recherche Scientifique, UMR 5277, Toulouse, France
| | - K A Goodrich
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J C Holmes
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - J E Stawarz
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - A P Sturner
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
- Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80303, USA
| | - D M Malaspina
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - M E Usanova
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA
| | - K J Trattner
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, 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
| | - P-A Lindqvist
- KTH Royal Institute of Technology, SE-11428 Stockholm, Sweden
| | - J F Drake
- University of Maryland, College Park, Maryland 20742, USA
| | - M A Shay
- University of Delaware, Newark, Delaware 19716, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, 8042 Graz, Austria
| | - G T Marklund
- KTH Royal Institute of Technology, SE-11428 Stockholm, Sweden
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26
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Schmid D, Nakamura R, Volwerk M, Plaschke F, Narita Y, Baumjohann W, Magnes W, Fischer D, Eichelberger HU, Torbert RB, Russell CT, Strangeway RJ, Leinweber HK, Le G, Bromund KR, Anderson BJ, Slavin JA, Kepko EL. A comparative study of dipolarization fronts at MMS and Cluster. Geophys Res Lett 2016; 43:6012-6019. [PMID: 27478286 PMCID: PMC4949994 DOI: 10.1002/2016gl069520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 05/26/2016] [Indexed: 06/02/2023]
Abstract
We present a statistical study of dipolarization fronts (DFs), using magnetic field data from MMS and Cluster, at radial distances below 12 RE and 20 RE , respectively. Assuming that the DFs have a semicircular cross section and are propelled by the magnetic tension force, we used multispacecraft observations to determine the DF velocities. About three quarters of the DFs propagate earthward and about one quarter tailward. Generally, MMS is in a more dipolar magnetic field region and observes larger-amplitude DFs than Cluster. The major findings obtained in this study are as follows: (1) At MMS ∼57 % of the DFs move faster than 150 km/s, while at Cluster only ∼35 %, indicating a variable flux transport rate inside the flow-braking region. (2) Larger DF velocities correspond to higher Bz values directly ahead of the DFs. We interpret this as a snow plow-like phenomenon, resulting from a higher magnetic flux pileup ahead of DFs with higher velocities.
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Affiliation(s)
- D. Schmid
- Space Research InstituteAustrian Academy of SciencesGrazAustria
- NAWI GrazUniversity of GrazGrazAustria
| | - R. Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - M. Volwerk
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - F. Plaschke
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Y. Narita
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - W. Baumjohann
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - W. Magnes
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - D. Fischer
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | | | - R. B. Torbert
- Institute for the Study of Earth, Oceans, and SpaceUniversity of New HampshireDurhamNew HampshireUSA
- Southwest Research InstituteSan AntonioTexasUSA
| | - C. T. Russell
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - H. K. Leinweber
- Institute of Geophysics and Planetary PhysicsUniversity of CaliforniaLos AngelesCaliforniaUSA
| | - G. Le
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - K. R. Bromund
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
| | - B. J. Anderson
- The Johns Hopkins Applied Physics LaboratoryLaurelMarylandUSA
| | - J. A. Slavin
- Department of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMichiganUSA
| | - E. L. Kepko
- NASA Goddard Space Flight CenterGreenbeltMarylandUSA
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27
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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. Phys Rev Lett 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Nakamura R, Sergeev VA, Baumjohann W, Plaschke F, Magnes W, Fischer D, Varsani A, Schmid D, Nakamura TKM, Russell CT, Strangeway RJ, Leinweber HK, Le G, Bromund KR, Pollock CJ, Giles BL, Dorelli JC, Gershman DJ, Paterson W, Avanov LA, Fuselier SA, Genestreti K, Burch JL, Torbert RB, Chutter M, Argall MR, Anderson BJ, Lindqvist P, Marklund GT, Khotyaintsev YV, Mauk BH, Cohen IJ, Baker DN, Jaynes AN, Ergun RE, Singer HJ, Slavin JA, Kepko EL, Moore TE, Lavraud B, Coffey V, Saito Y. Transient, small-scale field-aligned currents in the plasma sheet boundary layer during storm time substorms. Geophys Res Lett 2016; 43:4841-4849. [PMID: 27867235 PMCID: PMC5111425 DOI: 10.1002/2016gl068768] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 04/26/2016] [Accepted: 05/03/2016] [Indexed: 06/02/2023]
Abstract
We report on field-aligned current observations by the four Magnetospheric Multiscale (MMS) spacecraft near the plasma sheet boundary layer (PSBL) during two major substorms on 23 June 2015. Small-scale field-aligned currents were found embedded in fluctuating PSBL flux tubes near the separatrix region. We resolve, for the first time, short-lived earthward (downward) intense field-aligned current sheets with thicknesses of a few tens of kilometers, which are well below the ion scale, on flux tubes moving equatorward/earthward during outward plasma sheet expansion. They coincide with upward field-aligned electron beams with energies of a few hundred eV. These electrons are most likely due to acceleration associated with a reconnection jet or high-energy ion beam-produced disturbances. The observations highlight coupling of multiscale processes in PSBL as a consequence of magnetotail reconnection.
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29
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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. Geophys Res Lett 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] [What about the content of this article? (0)] [Affiliation(s)] [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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30
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Burch JL, Torbert RB, Phan TD, Chen LJ, Moore TE, Ergun RE, Eastwood JP, Gershman DJ, Cassak PA, Argall MR, Wang S, Hesse M, Pollock CJ, Giles BL, Nakamura R, Mauk BH, Fuselier SA, Russell CT, Strangeway RJ, Drake JF, Shay MA, Khotyaintsev YV, Lindqvist PA, Marklund G, Wilder FD, Young DT, Torkar K, Goldstein J, Dorelli JC, Avanov LA, Oka M, Baker DN, Jaynes AN, Goodrich KA, Cohen IJ, Turner DL, Fennell JF, Blake JB, Clemmons J, Goldman M, Newman D, Petrinec SM, Trattner KJ, Lavraud B, Reiff PH, Baumjohann W, Magnes W, Steller M, Lewis W, Saito Y, Coffey V, Chandler M. Electron-scale measurements of magnetic reconnection in space. Science 2016; 352:aaf2939. [PMID: 27174677 DOI: 10.1126/science.aaf2939] [Citation(s) in RCA: 438] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/03/2016] [Indexed: 11/02/2022]
Abstract
Magnetic reconnection is a fundamental physical process in plasmas whereby stored magnetic energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using measurements with very high time resolution, NASA's Magnetospheric Multiscale (MMS) mission has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth's magnetosphere where the interplanetary magnetic field reconnects with the terrestrial magnetic field. We have (i) observed the conversion of magnetic energy to particle energy; (ii) measured the electric field and current, which together cause the dissipation of magnetic energy; and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region.
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Affiliation(s)
- J L Burch
- Southwest Research Institute, San Antonio, TX, USA.
| | - R B Torbert
- Southwest Research Institute, San Antonio, TX, USA. University of New Hampshire, Durham, NH, USA
| | - T D Phan
- University of California, Berkeley, CA, USA
| | - L-J Chen
- University of Maryland, College Park, MD, USA
| | - T E Moore
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - R E Ergun
- University of Colorado LASP, Boulder, CO, USA
| | - J P Eastwood
- Blackett Laboratory, Imperial College London, London, UK
| | - D J Gershman
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - P A Cassak
- West Virginia University, Morgantown, WV, USA
| | - M R Argall
- University of New Hampshire, Durham, NH, USA
| | - S Wang
- University of Maryland, College Park, MD, USA
| | - M Hesse
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - C J Pollock
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - B L Giles
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - B H Mauk
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - S A Fuselier
- Southwest Research Institute, San Antonio, TX, USA
| | - C T Russell
- University of California, Los Angeles, CA, USA
| | | | - J F Drake
- University of Maryland, College Park, MD, USA
| | - M A Shay
- University of Delaware, Newark, DE, USA
| | | | | | - G Marklund
- Royal Institute of Technology, Stockholm, Sweden
| | - F D Wilder
- University of Colorado LASP, Boulder, CO, USA
| | - D T Young
- Southwest Research Institute, San Antonio, TX, USA
| | - K Torkar
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - J Goldstein
- Southwest Research Institute, San Antonio, TX, USA
| | - J C Dorelli
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - L A Avanov
- NASA, Goddard Space Flight Center, Greenbelt, MD, USA
| | - M Oka
- University of California, Berkeley, CA, USA
| | - D N Baker
- University of Colorado LASP, Boulder, CO, USA
| | - A N Jaynes
- University of Colorado LASP, Boulder, CO, USA
| | | | - I J Cohen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - D L Turner
- Aerospace Corporation, El Segundo, CA, USA
| | | | - J B Blake
- Aerospace Corporation, El Segundo, CA, USA
| | - J Clemmons
- Aerospace Corporation, El Segundo, CA, USA
| | - M Goldman
- University of Colorado, Boulder, CO, USA
| | - D Newman
- University of Colorado, Boulder, CO, USA
| | - S M Petrinec
- Lockheed Martin Advanced Technology Center, Palo Alto, CA, USA
| | | | - B Lavraud
- Institut de Recherche en Astrophysique et Planétologie, Toulouse, France
| | - P H Reiff
- Department of Physics and Astronomy, Rice University, Houston, TX, USA
| | - W Baumjohann
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - W Magnes
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - M Steller
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - W Lewis
- Southwest Research Institute, San Antonio, TX, USA
| | - Y Saito
- Institute for Space and Astronautical Sciences, Sagamihara, Japan
| | - V Coffey
- NASA, Marshall Space Flight Center, Huntsville, AL, USA
| | - M Chandler
- NASA, Marshall Space Flight Center, Huntsville, AL, USA
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31
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Tsutsui M, Strangeway RJ, Tsurutani BT, Matsumoto H, Phillips JL, Ashour-Abdalla M. Wave mode identification of electrostatic noise observed with ISEE 3 in the deep tail boundary layer. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/91ja00925] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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32
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Daniels JTM, Russell CT, Strangeway RJ, Wei HY, Zhang TL. Whistler mode bursts in the Venus ionosphere due to lightning: Statistical properties using Venus Express magnetometer observations. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011je003897] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
The sawtooth mode of convection of Earth's magnetosphere is a 2- to 4-hour planetary-scale oscillation powered by the solar wind-magnetosphere-ionosphere (SW-M-I) interaction. Using global simulations of geospace, we have shown that ionospheric O(+) outflows can generate sawtooth oscillations. As the outflowing ions fill the inner magnetosphere, their pressure distends the nightside magnetic field. When the outflow fluence exceeds a threshold, magnetic field tension cannot confine the accumulating fluid; an O(+)-rich plasmoid is ejected, and the field dipolarizes. Below the threshold, the magnetosphere undergoes quasi-steady convection. Repetition and the sawtooth period are controlled by the strength of the SW-M-I interaction, which regulates the outflow fluence.
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Affiliation(s)
- O J Brambles
- Thayer School of Engineering, Dartmouth College, Hanover, NH, USA.
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Jian LK, Russell CT, Luhmann JG, Anderson BJ, Boardsen SA, Strangeway RJ, Cowee MM, Wennmacher A. Observations of ion cyclotron waves in the solar wind near 0.3 AU. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010ja015737] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- L. K. Jian
- Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
| | - C. T. Russell
- Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
| | - J. G. Luhmann
- Space Science Laboratory; University of California; Berkeley California USA
| | - B. J. Anderson
- Applied Physics Laboratory; Johns Hopkins University; Baltimore Maryland USA
| | - S. A. Boardsen
- Heliophysics Science Division; NASA Goddard Space Flight Center; Greenbelt Maryland USA
- Goddard Earth Sciences and Technology Center; University of Maryland; Baltimore Maryland USA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
| | - M. M. Cowee
- Space Science and Applications (ISR-1); Los Alamos National Laboratory; Los Alamos New Mexico USA
| | - A. Wennmacher
- Institute of Geophysics and Meteorology; University of Cologne; Cologne Germany
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35
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Chaston CC, Salem C, Bonnell JW, Carlson CW, Ergun RE, Strangeway RJ, McFadden JP. The turbulent Alfvénic aurora. Phys Rev Lett 2008; 100:175003. [PMID: 18518303 DOI: 10.1103/physrevlett.100.175003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Indexed: 05/26/2023]
Abstract
It is demonstrated from observations that the Alfvénic aurora may be powered by a turbulent cascade transverse to the geomagnetic field from large MHD scales to small Alfvén wave scales of several electron skin depths and less. We show that the energy transport through the cascade is sufficient to drive the observed acceleration of electrons from near-Earth space to form the aurora. We find that regions of Alfvén wave dissipation, and particle acceleration, are localized or intermittent and embedded within a near-homogeneous background of large-scale MHD structures.
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Affiliation(s)
- C C Chaston
- Space Science Laboratory, University of California, Berkeley, California 94720, USA
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36
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Russell CT, Zhang TL, Delva M, Magnes W, Strangeway RJ, Wei HY. Lightning on Venus inferred from whistler-mode waves in the ionosphere. Nature 2007; 450:661-2. [DOI: 10.1038/nature05930] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Accepted: 05/01/2007] [Indexed: 11/09/2022]
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37
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Su YJ, Ergun RE, Jones ST, Strangeway RJ, Chaston CC, Parker SE, Horwitz JL. Generation of short-burst radiation through Alfvénic acceleration of auroral electrons. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006ja012131] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yi-Jiun Su
- Department of Physics; University of Texas at Arlington; Arlington Texas USA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - S. T. Jones
- Department of Physics; University of Texas at Arlington; Arlington Texas USA
| | - R. J. Strangeway
- Institute for Geophysical and Planetary Physics; University of California; Los Angeles California USA
| | - C. C. Chaston
- Space Sciences Laboratory; University of California; Berkeley California USA
| | - S. E. Parker
- The Center for Integrated Plasma Studies; University of Colorado; Boulder Colorado USA
| | - J. L. Horwitz
- Department of Physics; University of Texas at Arlington; Arlington Texas USA
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38
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Chaston CC, Hull AJ, Bonnell JW, Carlson CW, Ergun RE, Strangeway RJ, McFadden JP. Large parallel electric fields, currents, and density cavities in dispersive Alfvén waves above the aurora. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006ja012007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- C. C. Chaston
- Space Sciences Laboratory; University of California; Berkeley California USA
| | - A. J. Hull
- Space Sciences Laboratory; University of California; Berkeley California USA
| | - J. W. Bonnell
- Space Sciences Laboratory; University of California; Berkeley California USA
| | - C. W. Carlson
- Space Sciences Laboratory; University of California; Berkeley California USA
| | - R. E. Ergun
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - R. J. Strangeway
- Institute for Geophysical and Planetary Physics; University of California; Los Angeles California USA
| | - J. P. McFadden
- Space Sciences Laboratory; University of California; Berkeley California USA
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Russell CT, Luhmann JG, Cravens TE, Nagy AF, Strangeway RJ. Venus upper atmosphere and plasma environment: Critical issues for future exploration. Exploring Venus as a Terrestrial Planet 2007. [DOI: 10.1029/176gm09] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Bortnik J, Thorne RM, O'Brien TP, Green JC, Strangeway RJ, Shprits YY, Baker DN. Observation of two distinct, rapid loss mechanisms during the 20 November 2003 radiation belt dropout event. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006ja011802] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Pritchett PL, Strangeway RJ, Ergun RE, Carlson CW. Generation and propagation of cyclotron maser emissions in the finite auroral kilometric radiation source cavity. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2002ja009403] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- P. L. Pritchett
- Department of Physics and Astronomy; University of California; Los Angeles California USA
| | - R. J. Strangeway
- Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
| | - R. E. Ergun
- Department of Astrophysical and Planetary Sciences and Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - C. W. Carlson
- Space Sciences Laboratory; University of California; Berkeley California USA
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Russell CT, Wang YL, Blanco-Cano X, Strangeway RJ. The Io mass-loading disk: Constraints provided by ion cyclotron wave observations. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2001ja900029] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ergun RE, Su YJ, Andersson L, Carlson CW, McFadden JP, Mozer FS, Newman DL, Goldman MV, Strangeway RJ. Direct observation of localized parallel electric fields in a space plasma. Phys Rev Lett 2001; 87:045003. [PMID: 11461625 DOI: 10.1103/physrevlett.87.045003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2001] [Revised: 05/23/2001] [Indexed: 05/23/2023]
Abstract
We report direct measurements of parallel electric fields related to particle acceleration in a collisionless space plasma. The electric field is that of a monotonic potential ramp localized to approximately 10 debye lengths along the magnetic field. Electrons accelerated by the parallel electric field are accompanied by intense electrostatic waves and nonlinear structures interpreted as electron phase-space holes.
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Affiliation(s)
- R E Ergun
- The Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80309, USA
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Strangeway RJ, Russell CT, Carlson CW, McFadden JP, Ergun RE, Temerin M, Klumpar DM, Peterson WK, Moore TE. Cusp field-aligned currents and ion outflows. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000ja900032] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Russell CT, Huddleston DE, Strangeway RJ, Blanco-Cano X, Kivelson MG, Khurana KK, Frank LA, Paterson W, Gurnett DA, Kurth WS. Mirror-mode structures at the Galileo-Io flyby: Observations. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999ja900202] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Huddleston DE, Strangeway RJ, Blanco-Cano X, Russell CT, Kivelson MG, Khurana KK. Mirror-mode structures at the Galileo-Io flyby: Instability criterion and dispersion analysis. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999ja900195] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Song P, Zhu Z, Russell CT, Anderson RR, Gurnett DA, Ogilvie KW, Strangeway RJ. Properties of ELF emissions in the dayside magnetopause. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98ja02396] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Huddleston DE, Strangeway RJ, Warnecke J, Russell CT, Kivelson MG. Ion cyclotron waves in the Io torus: Wave dispersion, free energy analysis, and SO2+source rate estimates. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/97je03557] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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