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Trattner KJ, Petrinec SM, Fuselier SA. The Location of Magnetic Reconnection at Earth's Magnetopause. Space Sci Rev 2021; 217:41. [PMID: 34720216 PMCID: PMC8550343 DOI: 10.1007/s11214-021-00817-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 03/08/2021] [Indexed: 06/13/2023]
Abstract
One of the major questions about magnetic reconnection is how specific solar wind and interplanetary magnetic field conditions influence where reconnection occurs at the Earth's magnetopause. There are two reconnection scenarios discussed in the literature: a) anti-parallel reconnection and b) component reconnection. Early spacecraft observations were limited to the detection of accelerated ion beams in the magnetopause boundary layer to determine the general direction of the reconnection X-line location with respect to the spacecraft. An improved view of the reconnection location at the magnetopause evolved from ionospheric emissions observed by polar-orbiting imagers. These observations and the observations of accelerated ion beams revealed that both scenarios occur at the magnetopause. Improved methodology using the time-of-flight effect of precipitating ions in the cusp regions and the cutoff velocity of the precipitating and mirroring ion populations was used to pinpoint magnetopause reconnection locations for a wide range of solar wind conditions. The results from these methodologies have been used to construct an empirical reconnection X-line model known as the Maximum Magnetic Shear model. Since this model's inception, several tests have confirmed its validity and have resulted in modifications to the model for certain solar wind conditions. This review article summarizes the observational evidence for the location of magnetic reconnection at the Earth's magnetopause, emphasizing the properties and efficacy of the Maximum Magnetic Shear Model.
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Affiliation(s)
| | | | - S. A. Fuselier
- Southwest Research Institute, San Antonio, TX USA
- University of Texas at San Antonio, San Antonio, TX USA
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2
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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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3
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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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Luspay-Kuti A, Altwegg K, Berthelier JJ, Beth A, Dhooghe F, Fiethe B, Fuselier SA, Gombosi TI, Hansen KC, Hässig M, Livadiotis G, Mall U, Mandt KE, Mousis O, Petrinec SM, Rubin M, Trattner KJ, Tzou CY, Wurz P. Comparison of neutral outgassing of comet 67P/Churyumov-Gerasimenko inbound and outbound beyond 3 AU from ROSINA/DFMS. Astron Astrophys 2019; 630:A30. [PMID: 32699429 PMCID: PMC7375265 DOI: 10.1051/0004-6361/201833536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
CONTEXT Pre-equinox measurements of comet 67P/Churyumov-Gerasimenko with the mass spectrometer ROSINA/DFMS on board the Rosetta spacecraft revealed a strongly heterogeneous coma. The abundances of major and various minor volatile species were found to depend on the latitude and longitude of the nadir point of the spacecraft. The observed time variability of coma species remained consistent for about three months up to equinox. The chemical variability could be generally interpreted in terms of surface temperature and seasonal effects superposed on some kind of chemical heterogeneity of the nucleus. AIMS We compare here pre-equinox (inbound) ROSINA/DFMS measurements from 2014 to measurements taken after the outbound equinox in 2016, both at heliocentric distances larger than 3 AU. For a direct comparison we limit our observations to the southern hemisphere. METHODS We report the similarities and differences in the concentrations and time variability of neutral species under similar insolation conditions (heliocentric distance and season) pre- and post-equinox, and interpret them in light of the previously published observations. In addition, we extend both the pre- and post-equinox analysis by comparing species concentrations with a mixture of CO2 and H2O. RESULTS Our results show significant changes in the abundances of neutral species in the coma from pre- to post-equinox that are indicative of seasonally driven nucleus heterogeneity. CONCLUSIONS The observed pre- and post-equinox patterns can generally be explained by the strong erosion in the southern hemisphere that moves volatile-rich layers near the surface.
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Affiliation(s)
- A Luspay-Kuti
- Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd., Laurel, MD 20723, USA
| | - K Altwegg
- Physikalisches Institut, University of Bern, Sidlerstr. 5, 3012 Bern, Switzerland
- Center for Space and Habitability (CSH), Universität Bern, Sidlerstr. 5, 3012 Bern, Switzerland
| | - J J Berthelier
- Laboratoire Atmosphères, Milieux, Observations Spatiales, Institut Pierre Simon Laplace, CNRS, Université Pierre et Marie Curie, 4 avenue de Neptune, 94100 Saint-Maur, France
| | - A Beth
- Department of Physics/SPAT, Imperial College London, London SW7 2AZ, UK
| | - F Dhooghe
- Belgian Institute for Space Aeronomy, BIRA-IASB, Ringlaan 3, 1180 Brussels, Belgium
- Center for Plasma Astrophysics, K.U. Leuven, Celestijnenlaan 200D, 3001 Heverlee, Belgium
| | - B Fiethe
- Institute of Computer and Network Engineering (IDA), TU Braunschweig, Hans-Sommer-Strasse 66, 38106 Braunschweig, Germany
| | - S A Fuselier
- Space Science Directorate, Southwest Research Institute, 6220 Culebra Rd., San Antonio, TX 78228, USA
| | - T I Gombosi
- Department of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward, Ann Arbor, MI 48109, USA
| | - K C Hansen
- Department of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward, Ann Arbor, MI 48109, USA
| | - M Hässig
- Space Science Directorate, Southwest Research Institute, 6220 Culebra Rd., San Antonio, TX 78228, USA
| | - G Livadiotis
- Space Science Directorate, Southwest Research Institute, 6220 Culebra Rd., San Antonio, TX 78228, USA
| | - U Mall
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - K E Mandt
- Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd., Laurel, MD 20723, USA
| | - O Mousis
- Laboratoire d'Astrophysique de Marseille, CNRS, Aix Marseille Université, 13388 Marseille, France
| | - S M Petrinec
- Lockheed Martin Space Systems Advanced Technology Center, 3251 Hanover St., Palo Alto, CA 94304, USA
| | - M Rubin
- Physikalisches Institut, University of Bern, Sidlerstr. 5, 3012 Bern, Switzerland
| | - K J Trattner
- Laboratory for Atmospheric and Space Physics, University of Colorado at Boulder, 3665 Discovery Dr., Boulder, CO 80309, USA
| | - C-Y Tzou
- Physikalisches Institut, University of Bern, Sidlerstr. 5, 3012 Bern, Switzerland
| | - P Wurz
- Physikalisches Institut, University of Bern, Sidlerstr. 5, 3012 Bern, Switzerland
- Center for Space and Habitability (CSH), Universität Bern, Sidlerstr. 5, 3012 Bern, Switzerland
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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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6
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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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7
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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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8
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Trattner KJ, Onsager TG, Petrinec SM, Fuselier SA. Distinguishing between pulsed and continuous reconnection at the dayside magnetopause. J Geophys Res Space Phys 2015; 120:1684-1696. [PMID: 27656333 PMCID: PMC5014232 DOI: 10.1002/2014ja020713] [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: 10/09/2014] [Revised: 01/22/2015] [Accepted: 01/25/2015] [Indexed: 06/06/2023]
Abstract
Magnetic reconnection has been established as the dominant mechanism by which magnetic fields in different regions change topology to create open magnetic field lines that allow energy and momentum to flow into the magnetosphere. One of the persistent problems of magnetic reconnection is the question of whether the process is continuous or intermittent and what input condition(s) might favor one type of reconnection over the other. Observations from imagers that record FUV emissions caused by precipitating cusp ions demonstrate the global nature of magnetic reconnection. Those images show continuous ionospheric emissions even during changing interplanetary magnetic field conditions. On the other hand, in situ observations from polar-orbiting satellites show distinctive cusp structures in flux distributions of precipitating ions, which are interpreted as the telltale signature of intermittent reconnection. This study uses a modification of the low-velocity cutoff method, which was previously successfully used to determine the location of the reconnection site, to calculate for the cusp ion distributions the "time since reconnection occurred." The "time since reconnection" is used to determine the "reconnection time" for the cusp magnetic field lines where these distributions have been observed. The profile of the reconnection time, either continuous or stepped, is a direct measurement of the nature of magnetic reconnection at the reconnection site. This paper will discuss a continuous and pulsed reconnection event from the Polar spacecraft to illustrate the methodology.
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Affiliation(s)
| | | | | | - S. A. Fuselier
- Southwest Research InstituteSan AntonioTexasUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTexasUSA
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Wright DM, Yeoman TK, Rae IJ, Storey J, Stockton-Chalk AB, Roeder JL, Trattner KJ. Ground-based and Polar spacecraft observations of a giant (Pg) pulsation and its associated source mechanism. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2001ja900022] [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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Fuselier SA, Trattner KJ, Petrinec SM. Cusp observations of high- and low-latitude reconnection for northward interplanetary magnetic field. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999ja900422] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.7] [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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Simpson JA, Connell JJ, Lopate C, McKibben RB, Zhang M, Anglin JD, Ferrando P, Rastoin C, Raviart A, Heber B, Muiller-Meliin R, Kunow H, Sierks H, Wibberenz G, Bothmer V, Marsden RG, Sanderson TR, Trattner KJ, Wenzel KP, Paizis C. Cosmic Ray and Solar Particle Investigations Over the South Polar Regions of the Sun. Science 1995; 268:1019-23. [PMID: 17774228 DOI: 10.1126/science.268.5213.1019] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Observations of galactic cosmic radiation and anomalous component nuclei with charged particle sensors on the Ulysses spacecraft showed that heliospheric magnetic field structure over the south solar pole does not permit substantially more direct access to the local interstellar cosmic ray spectrum than is possible in the equatorial zone. Fluxes of galactic cosmic rays and the anomalous component increased as a result of latitude gradients by less than 50% from the equator to -80 degrees . Thus, the modulated cosmic ray nucleon, electron, and anomalous component fluxes are nearly spherically symmetric in the inner solar system. The cosmic rays and the anomalous nuclear component underwent a continuous, -26 day recurrent modulation to -80.2 degrees , whereas all recurring magnetic field compressions and recurring streams in the solar wind disappeared above approximately 55 degrees S latitude.
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