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Manzini D, Sahraoui F, Califano F. Cascade-Dissipation Balance in Astrophysical Plasmas: Insights from the Terrestrial Magnetosheath. PHYSICAL REVIEW LETTERS 2024; 132:235201. [PMID: 38905675 DOI: 10.1103/physrevlett.132.235201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 03/28/2024] [Accepted: 05/02/2024] [Indexed: 06/23/2024]
Abstract
The differential heating of electrons and ions by turbulence in weakly collisional magnetized plasmas and the scales at which such energy dissipation is most effective are still debated. Using a large data sample measured in Earth's magnetosheath by the magnetospheric multiscale mission and the coarse-grained energy equations derived from the Vlasov-Maxwell system, we find evidence of a balance over two decades in scales between the energy cascade and dissipation rates. The decline of the cascade rate at kinetic scales (in contrast with a constant one in the inertial range), is balanced by an increasing ion and electron heating rates, estimated via the pressure strain. Ion scales are found to contribute most effectively to ion heating, while electron heating originates from both ion and electron scales. These results can potentially impact the current understanding of particle heating in turbulent magnetized plasmas as well as their theoretical and numerical modeling.
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Affiliation(s)
- D Manzini
- Laboratoire de Physique des Plasmas (LPP), CNRS, École Polytechnique, Sorbonne Université, Université Paris-Saclay, Observatoire de Paris, 91120 Palaiseau, France
- Dipartimento di Fisica E. Fermi, University of Pisa, Italy
| | - F Sahraoui
- Laboratoire de Physique des Plasmas (LPP), CNRS, École Polytechnique, Sorbonne Université, Université Paris-Saclay, Observatoire de Paris, 91120 Palaiseau, France
| | - F Califano
- Dipartimento di Fisica E. Fermi, University of Pisa, Italy
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2
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Walsh BM, Kuntz KD, Busk S, Cameron T, Chornay D, Chuchra A, Collier MR, Connor C, Connor HK, Cravens TE, Dobson N, Galeazzi M, Kim H, Kujawski J, Paw U CK, Porter FS, Naldoza V, Nutter R, Qudsi R, Sibeck DG, Sembay S, Shoemaker M, Simms K, Thomas NE, Atz E, Winkert G. The Lunar Environment Heliophysics X-ray Imager (LEXI) Mission. SPACE SCIENCE REVIEWS 2024; 220:37. [PMID: 38756703 PMCID: PMC11093736 DOI: 10.1007/s11214-024-01063-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 03/26/2024] [Indexed: 05/18/2024]
Abstract
The Lunar Environment heliospheric X-ray Imager (LEXI) is a wide field-of-view soft X-ray telescope developed to study solar wind-magnetosphere coupling. LEXI is part of the Blue Ghost 1 mission comprised of 10 payloads to be deployed on the lunar surface. LEXI monitors the dayside magnetopause position and shape as a function of time by observing soft X-rays (0.1-2 keV) emitted from solar wind charge-exchange between exospheric neutrals and high charge-state solar wind plasma in the dayside magnetosheath. Measurements of the shape and position of the magnetopause are used to test temporal models of meso- and macro-scale magnetic reconnection. To image the boundary, LEXI employs lobster-eye optics to focus X-rays to a microchannel plate detector with a 9.1× ∘ 9.1 ∘ field of view.
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Affiliation(s)
- B. M. Walsh
- Center for Space Physics, Boston University, Boston, 02215 MA USA
| | - K. D. Kuntz
- The Henry A. Rowland Department of Physics and Astronomy, Johns Hopkins University, Baltimore, 21218 MD USA
| | - S. Busk
- Center for Space Physics, Boston University, Boston, 02215 MA USA
| | - T. Cameron
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - D. Chornay
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | | | - M. R. Collier
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - C. Connor
- Center for Space Physics, Boston University, Boston, 02215 MA USA
| | - H. K. Connor
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - T. E. Cravens
- Department of Physics and Astronomy, University of Kansas, Lawrence, 66045 KS USA
| | - N. Dobson
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - M. Galeazzi
- Department of Physics, University of Miami, Miami, 33146 FL USA
| | - H. Kim
- Space Research Institute, Austrian Academy of Sciences, Graz, Austria
| | - J. Kujawski
- Brandywine Photonics, College Station, 77845 TX USA
| | - C. K. Paw U
- Center for Space Physics, Boston University, Boston, 02215 MA USA
| | - F. S. Porter
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - V. Naldoza
- Center for Space Physics, Boston University, Boston, 02215 MA USA
| | - R. Nutter
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - R. Qudsi
- Center for Space Physics, Boston University, Boston, 02215 MA USA
| | - D. G. Sibeck
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - S. Sembay
- School of Physics and Astronomy, University of Leicester, Leicester, UK
| | - M. Shoemaker
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - K. Simms
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
| | - N. E. Thomas
- Marshall Space Flight Center, NASA, Huntsville, 35808 AL USA
| | - E. Atz
- Center for Space Physics, Boston University, Boston, 02215 MA USA
| | - G. Winkert
- NASA, Goddard Space Flight Center, Greenbelt, 20771 MD USA
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3
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Vuorinen L, LaMoury AT, Hietala H, Koller F. Magnetosheath Jets Over Solar Cycle 24: An Empirical Model. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2023JA031493. [PMID: 38440390 PMCID: PMC10909464 DOI: 10.1029/2023ja031493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/15/2023] [Accepted: 07/10/2023] [Indexed: 03/06/2024]
Abstract
Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft have been sampling the subsolar magnetosheath since the first dayside science phase in 2008, and we finally have observations over a solar cycle. However, we show that the solar wind coverage during these magnetosheath intervals is not always consistent with the solar wind conditions throughout the same year. This has implications for studying phenomena whose occurrence depends strongly on solar wind parameters. We demonstrate this with magnetosheath jets-flows of enhanced earthward dynamic pressure in the magnetosheath. Jets emerge from the bow shock, and some of them can go on and collide into the magnetopause. Their occurrence is highly linked to solar wind conditions, particularly the orientation of the interplanetary magnetic field, as jets are mostly observed downstream of the quasi-parallel shock. We study the yearly occurrence rates of jets recorded by THEMIS over solar cycle 24 (2008-2019) and find that they are biased due to differences in spacecraft orbits and uneven sampling of solar wind conditions during the different years. Thus, we instead use the THEMIS observations and their corresponding solar wind conditions to develop a model of how jet occurrence varies as a function of solar wind conditions. We then use OMNI data of the whole solar cycle to estimate the unbiased yearly jet occurrence rates. For comparison, we also estimate jet occurrence rates during solar cycle 23 (1996-2008). Our results suggest that there is no strong solar cycle dependency in jet formation.
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Affiliation(s)
- Laura Vuorinen
- Department of Physics and AstronomyUniversity of TurkuTurkuFinland
| | | | - Heli Hietala
- Department of Physics and AstronomyUniversity of TurkuTurkuFinland
- Blackett LaboratoryImperial College LondonLondonUK
- Department of Physics and AstronomyQueen Mary University of LondonLondonUK
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4
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Blanco‐Cano X, Rojas‐Castillo D, Kajdič P, Preisser L. Jets and Mirror Mode Waves in Earth's Magnetosheath. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2023; 128:e2022JA031221. [PMID: 38439786 PMCID: PMC10909539 DOI: 10.1029/2022ja031221] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 06/26/2023] [Accepted: 07/04/2023] [Indexed: 03/06/2024]
Abstract
Magnetosheath jets are localized plasma structures with high dynamic pressure which are frequently observed downstream of the Earth's bow shock. In this work we analyze Magnetospheric MultiScale magnetic field and plasma data and show that jets can be found in the quasi-perpendicular magnetosheath in regions permeated by Mirror mode waves (MMWs). We show that structures identified as jets by their enhanced dynamic pressure can have very different internal structure, with variable signatures in magnetic field magnitude and components, velocity, and density and can be associated to ion distribution functions of various types. This suggests that jets observed in the quasi-perpendicular magnetosheath are generated by different mechanisms. We find that jets can be related to traveling foreshocks, flux transfer events, and some have MMWs inside them. Our results suggest that some jets have a local source and their formation does not depend on upstream structures. We find that different types of ion distributions can exist inside the jets, while in some cases anisotropic distributions are present, in others counterstreaming distributions exist. We also show that for jets with MMWs inside them, ion distributions can be modulated. This highlights the importance of using ion distributions to identify and classify different types of jets.
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Affiliation(s)
- X. Blanco‐Cano
- Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación Científica s/nCiudad UniversitariaMexico CityMexico
| | - D. Rojas‐Castillo
- Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación Científica s/nCiudad UniversitariaMexico CityMexico
| | - P. Kajdič
- Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación Científica s/nCiudad UniversitariaMexico CityMexico
| | - L. Preisser
- Space Research InstituteAustrian Academy of SciencesGrazAustria
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5
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Manweiler JW, Breneman A, Niehof J, Larsen B, Romeo G, Stephens G, Halford A, Kletzing C, Brown LE, Spence H, Reeves G, Friedel R, Smith S, Skoug R, Blake B, Baker D, Kanekal S, Hoxie V, Jaynes A, Wygant J, Bonnell J, Crawford D, Gkioulidou M, Lanzerotti LJ, Mitchell DG, Gerrard A, Ukhorskiy A, Sotirelis T, Barnes RJ, Millan R, Harris B. Science of the Van Allen Probes Science Operations Centers. SPACE SCIENCE REVIEWS 2022; 218:66. [PMID: 36407497 PMCID: PMC9668807 DOI: 10.1007/s11214-022-00919-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 07/07/2022] [Indexed: 06/16/2023]
Abstract
The Van Allen Probes mission operations materialized through a distributed model in which operational responsibility was divided between the Mission Operations Center (MOC) and separate instrument specific SOCs. The sole MOC handled all aspects of telemetering and receiving tasks as well as certain scientifically relevant ancillary tasks. Each instrument science team developed individual instrument specific SOCs proficient in unique capabilities in support of science data acquisition, data processing, instrument performance, and tools for the instrument team scientists. In parallel activities, project scientists took on the task of providing a significant modeling tool base usable by the instrument science teams and the larger scientific community. With a mission as complex as Van Allen Probes, scientific inquiry occurred due to constant and significant collaboration between the SOCs and in concert with the project science team. Planned cross-instrument coordinated observations resulted in critical discoveries during the seven-year mission. Instrument cross-calibration activities elucidated a more seamless set of data products. Specific topics include post-launch changes and enhancements to the SOCs, discussion of coordination activities between the SOCs, SOC specific analysis software, modeling software provided by the Van Allen Probes project, and a section on lessons learned. One of the most significant lessons learned was the importance of the original decision to implement individual team SOCs providing timely and well-documented instrument data for the NASA Van Allen Probes Mission scientists and the larger magnetospheric and radiation belt scientific community.
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Affiliation(s)
| | | | | | - Brian Larsen
- ECT, Los Alamos National Laboratory, Los Alamos, NM USA
| | - Giuseppe Romeo
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | - Grant Stephens
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | | | | | - Lawrence E. Brown
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | | | - Geoff Reeves
- ECT, Los Alamos National Laboratory, Los Alamos, NM USA
| | | | - Sonya Smith
- ECT, University of New Hampshire, Durham, NH USA
| | - Ruth Skoug
- ECT, Los Alamos National Laboratory, Los Alamos, NM USA
| | - Bern Blake
- ECT, Aerospace Corporation, Los Angeles, CA USA
| | - Dan Baker
- ECT, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | - Shri Kanekal
- ECT, Goddard Spaceflight Center, Greenbelt, MD USA
| | - Vaughn Hoxie
- ECT, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA
| | | | - John Wygant
- EFW, University of Minnesota, Minneapolis, MN USA
| | - John Bonnell
- EFW, University of California-Berkley, Berkley, CA USA
| | | | - Matina Gkioulidou
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | | | - Donald G. Mitchell
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | - Andrew Gerrard
- RBSPICE, New Jersey Institute of Technology, Newark, NJ USA
| | - Aleksandr Ukhorskiy
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | - Thomas Sotirelis
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | - Robin J. Barnes
- RBSPICE and Project, Applied Physics Laboratory, The Johns Hopkins University, Laurel, MD USA
| | | | - Blaine Harris
- RBSPICE, Fundamental Technologies, LLC, Lawrence, KS USA
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6
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George H, Reeves G, Cunningham G, Kalliokoski MMH, Kilpua E, Osmane A, Henderson MG, Morley SK, Hoilijoki S, Palmroth M. Contributions to Loss Across the Magnetopause During an Electron Dropout Event. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2022; 127:e2022JA030751. [PMID: 36591320 PMCID: PMC9787648 DOI: 10.1029/2022ja030751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/15/2022] [Accepted: 09/23/2022] [Indexed: 06/17/2023]
Abstract
Dropout events are dramatic decreases in radiation belt electron populations that can occur in as little as 30 minutes. Loss to magnetopause due to a combination of magnetopause shadowing and outward radial transport plays a significant role in these events. We examine the dropout of relativistic electron populations during the October 2012 geomagnetic storm using simulated electron phase space density, evaluating the contribution of different processes to losses across the magnetopause. We compare loss contribution from outward transport calculated using a standard empirical radial diffusion model that assumes a dipolar geomagnetic field to an event-specific radial diffusion model evaluated with a non-dipolar geomagnetic field. We additionally evaluate the contribution of Shabansky type 1 particles, which bounce along magnetic field lines with local equatorial maxima, to the loss calculated during this event. We find that the empirical radial diffusion model with a dipolar background field underestimates the contribution of radial diffusion to this dropout event by up to 10% when compared to the event-specific, non-dipolar radial diffusion model. We additionally find that including Shabansky type 1 particles in the initial electron phase space density, that is, allowing some magnetic field lines distorted from the typical single-minima configuration in drift shell construction, increases the calculated loss by an average of 0.75%. This shows that the treatment of the geomagnetic field significantly impacts the calculation of electron losses to the magnetopause during dropout events, with the non-dipolar treatment of radial diffusion being essential to accurately quantify the loss of outer radiation belt populations.
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Affiliation(s)
- H. George
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - G. Reeves
- Intelligence and Space Research DivisionLos Alamos National LaboratoryLos AlamosNMUSA
| | - G. Cunningham
- Intelligence and Space Research DivisionLos Alamos National LaboratoryLos AlamosNMUSA
| | | | - E. Kilpua
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - A. Osmane
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - M. G. Henderson
- Intelligence and Space Research DivisionLos Alamos National LaboratoryLos AlamosNMUSA
| | - S. K. Morley
- Intelligence and Space Research DivisionLos Alamos National LaboratoryLos AlamosNMUSA
| | - S. Hoilijoki
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
| | - M. Palmroth
- Department of PhysicsUniversity of HelsinkiHelsinkiFinland
- Space and Earth Observation CenterFinnish Meteorological InstituteHelsinkiFinland
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7
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Koller F, Temmer M, Preisser L, Plaschke F, Geyer P, Jian LK, Roberts OW, Hietala H, LaMoury AT. Magnetosheath Jet Occurrence Rate in Relation to CMEs and SIRs. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2022; 127:e2021JA030124. [PMID: 35866074 PMCID: PMC9286365 DOI: 10.1029/2021ja030124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 03/17/2022] [Accepted: 03/23/2022] [Indexed: 06/15/2023]
Abstract
Magnetosheath jets constitute a significant coupling effect between the solar wind (SW) and the magnetosphere of the Earth. In order to investigate the effects and forecasting of these jets, we present the first-ever statistical study of the jet production during large-scale SW structures like coronal mass ejections (CMEs), stream interaction regions (SIRs) and high speed streams (HSSs). Magnetosheath data from Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft between January 2008 and December 2020 serve as measurement source for jet detection. Two different jet definitions were used to rule out statistical biases induced by our jet detection method. For the CME and SIR + HSS lists, we used lists provided by literature and expanded on incomplete lists using OMNI data to cover the time range of May 1996 to December 2020. We find that the number and total time of observed jets decrease when CME-sheaths hit the Earth. The number of jets is lower throughout the passing of the CME-magnetic ejecta (ME) and recovers quickly afterward. On the other hand, the number of jets increases during SIR and HSS phases. We discuss a few possibilities to explain these statistical results.
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Affiliation(s)
| | | | - Luis Preisser
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Ferdinand Plaschke
- Institut für Geophysik und extraterrestrische PhysikTU BraunschweigBraunschweigGermany
| | - Paul Geyer
- Institute of PhysicsUniversity of GrazGrazAustria
- Hvar Observatory, Faculty of GeodesyUniversity of ZagrebZagrebCroatia
| | - Lan K. Jian
- Heliophysics Science DivisionNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Owen W. Roberts
- Space Research InstituteAustrian Academy of SciencesGrazAustria
| | - Heli Hietala
- The Blackett LaboratoryImperial College LondonLondonUK
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8
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Kelvin–Helmholtz Waves on the Magnetopause at the Lunar Distances under Southward IMF: ARTEMIS Observations. UNIVERSE 2022. [DOI: 10.3390/universe8040209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The Kelvin–Helmholtz (KH) instability, a common phenomenon widely observed at the magnetopause, plays an important role in plasma transport while reconnection at low latitude is less efficient during the northward interplanetary magnetic field (IMF). In this study, we analyze the magnetic field and plasma observations obtained by the Acceleration, Reconnection, Turbulence, and Electrodynamics of Moon’s Interaction with the Sun (ARTEMIS) spacecraft located near the lunar orbit and find KH waves under the southward IMF at the lunar-orbit magnetopause. We also calculate the dominant period, phase velocity, and wavelength of the KH waves and further compare this event with the KH waves seen at the flank magnetopause under the southward IMF, which indicates that the wavelength increases as the distance from the subsolar point increases. The observations also show that the KH waves at lunar distance under the southward IMF are characterized by irregularity and intermittence.
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9
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Takahashi K, Crabtree C, Ukhorskiy AY, Boyd A, Denton RE, Turner D, Gkioulidou M, Vellante M, Spence HE. Van Allen Probes Observations of Symmetric Stormtime Compressional ULF Waves. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2022; 127:e2021JA030115. [PMID: 35847659 PMCID: PMC9285050 DOI: 10.1029/2021ja030115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/16/2021] [Accepted: 01/23/2022] [Indexed: 06/15/2023]
Abstract
Previous spacecraft studies showed that stormtime poloidal ultralow-frequency (ULF) waves in the ring current region have an antisymmetric (second harmonic) mode structure about the magnetic equator. This paper reports Van Allen Probes observations of symmetric ULF waves in the postnoon sector during a moderate geomagnetic storm. The mode structure is determined from the presence of purely compressional magnetic field oscillations at the equator accompanied by strong transverse electric field perturbations. Antisymmetric waves were also detected but only very late in the recovery phase. The symmetric waves were detected outside the plasmasphere at L = 3.0-5.5 and had peak power at 4-10 mHz, lower than the frequency of the local fundamental toroidal standing Alfvén wave. During the wave events, the flux of protons was enhanced at energies below ∼5 keV, which appears to be a prerequisite for the waves. The protons may provide free energies to waves through drift resonance instability or drift compressional instability, which occur in the presence of radial gradients of plasma parameters.
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Affiliation(s)
- Kazue Takahashi
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | | | - A. Y. Ukhorskiy
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - Alexander Boyd
- Department of Space ScienceAerospace CorporationChantillyVAUSA
| | | | - Drew Turner
- The Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | | | - Massimo Vellante
- Department of Physical and Chemical SciencesUniversity of L’AquilaL’AquilaItaly
- Consorzio Area di Ricerca in AstrogeofisicaL’AquilaItaly
| | - Harlan E. Spence
- Institute for the Study of Earth, Oceans, and Space, University of New HampshireDurhamNHUSA
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10
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Staples FA, Kellerman A, Murphy KR, Rae IJ, Sandhu JK, Forsyth C. Resolving Magnetopause Shadowing Using Multimission Measurements of Phase Space Density. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2022; 127:e2021JA029298. [PMID: 35864842 PMCID: PMC9286781 DOI: 10.1029/2021ja029298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 12/21/2021] [Accepted: 01/10/2022] [Indexed: 06/15/2023]
Abstract
Loss mechanisms act independently or in unison to drive rapid loss of electrons in the radiation belts. Electrons may be lost by precipitation into the Earth's atmosphere, or through the magnetopause into interplanetary space-a process known as magnetopause shadowing. While magnetopause shadowing is known to produce dropouts in electron flux, it is unclear if shadowing continues to remove particles in tandem with electron acceleration processes, limiting the overall flux increase. We investigated the contribution of shadowing to overall radiation belt fluxes throughout a geomagnetic storm starting on the 7 September 2017. We use new, multimission phase space density calculations to decipher electron dynamics during each storm phase and identify features of magnetopause shadowing during both the net-loss and the net-acceleration storm phases on sub-hour time scales. We also highlight two distinct types of shadowing; "direct," where electrons are lost as their orbit intersects the magnetopause, and "indirect," where electrons are lost through ULF wave driven radial transport toward the magnetopause boundary.
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Affiliation(s)
- F. A. Staples
- Mullard Space Science LaboratoryUniversity College LondonLondonUK
| | - A. Kellerman
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | | | - I. J. Rae
- Northumbria UniversityNewcastle upon TyneUK
| | | | - C. Forsyth
- Mullard Space Science LaboratoryUniversity College LondonLondonUK
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11
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Zou Y, Walsh BM, Chen L, Ng J, Shi X, Wang C, Lyons LR, Liu J, Angelopoulos V, McWilliams KA, Michael Ruohoniemi J. Unsteady Magnetopause Reconnection Under Quasi-Steady Solar Wind Driving. GEOPHYSICAL RESEARCH LETTERS 2022; 49:e2021GL096583. [PMID: 35865078 PMCID: PMC9285935 DOI: 10.1029/2021gl096583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/16/2021] [Accepted: 12/20/2021] [Indexed: 06/15/2023]
Abstract
The intrinsic temporal nature of magnetic reconnection at the magnetopause has been an active area of research. Both temporally steady and intermittent reconnection have been reported. We examine the steadiness of reconnection using space-ground conjunctions under quasi-steady solar wind driving. The spacecraft suggests that reconnection is first inactive, and then activates. The radar further suggests that after activation, reconnection proceeds continuously but unsteadily. The reconnection electric field shows variations at frequencies below 10 mHz with peaks at 3 and 5 mHz. The variation amplitudes are ∼10-30 mV/m in the ionosphere, and 0.3-0.8 mV/m at the equatorial magnetopause. Such amplitudes represent 30%-60% of the peak reconnection electric field. The unsteadiness of reconnection can be plausibly explained by the fluctuating magnetic field in the turbulent magnetosheath. A comparison with a previous global hybrid simulation suggests that it is the foreshock waves that drive the magnetosheath fluctuations, and hence modulate the reconnection.
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Affiliation(s)
- Ying Zou
- Department of Space ScienceUniversity of Alabama in HuntsvilleHuntsvilleALUSA
| | - Brian M. Walsh
- Department of Mechanical Engineering and Center for Space PhysicsBoston UniversityBostonMAUSA
| | - Li‐Jen Chen
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Jonathan Ng
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | - Xueling Shi
- The Bradley Department of Electrical and Computer EngineeringVirginia TechBlacksburgVAUSA
- High Altitude ObservatoryNational Center for Atmospheric ResearchBoulderCOUSA
| | - Chih‐Ping Wang
- Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Larry R. Lyons
- Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Jiang Liu
- Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesCAUSA
- Department of Earth, Planetary and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Vassilis Angelopoulos
- Department of Earth, Planetary and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Kathryn A. McWilliams
- Department of Physics & Engineering PhysicsUniversity of SaskatchewanSaskatoonSKCanada
| | - J. Michael Ruohoniemi
- The Bradley Department of Electrical and Computer EngineeringVirginia TechBlacksburgVAUSA
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12
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Geomagnetic Activity at Lampedusa Island: Characterization and Comparison with the Other Italian Observatories, Also in Response to Space Weather Events. REMOTE SENSING 2021. [DOI: 10.3390/rs13163111] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Regular automatic recordings of the time series of the magnetic field, together with routine manual absolute measurements for establishing dynamic baselines at Lampedusa Island—south of Sicily—Italy (geographic coordinates 35°31′N; 12°32′E, altitude 33 m a.s.l.), show a signature of very low electromagnetic noise. The observatory (provisional IAGA code: LMP) lays inside a restricted and remote wildlife reserve, far away from the built-up and active areas of the island, which at present is the southernmost location of the European territory for such observations. The availability of high-quality data from such site, whose survey started in 2005, is valuable for filling the spatial gap due to the lack of observatories in the whole south Mediterranean and North African sectors. We compare observations at Lampedusa, in both time and frequency domains, with those at the other Italian observatories (Castello Tesino and Duronia-L’Aquila), operating since the 1960s of last century, allowing us to report even the secular variation. Using data recorded in the last few years, we investigate higher frequency variations (from diurnal to Pc3-4 pulsations) in order to magnetically characterize the Italian territory and the local response to external forcing. In particular, we present a characterization in terms of diurnal variation and its seasonal dependence for the three observatories. This latter feature is in good agreement with a geomagnetic Sq-model, leading us to speculate about the position of the north Sq-current system vortex and its seasonal displacement with respect to the geographic positions of the observatories. We also study the geomagnetic individual response to intense space weather events by performing Superposed Epoch Analysis (SEA), with an ad-hoc significance test. Magnetic responses in the Ultra Low Frequency range (ULF) from spectral, local Signal-to-Noise Ratio (SNR) analyses under different local time, and polarization rates are computed. These latter studies lead us to search for possible signatures of magnetic field line resonances during intense space weather events, using cross-phase multi-observatory analysis, revealing the promising detection capability of such technique even at low latitudes. The geomagnetic observatories prove to be important points of observation for space weather events occurring at different spatial and time scales, originating in both upstream and ionospheric regions, here analyzed by several well-established methodologies and techniques. The quiet environmental site of LMP, providing high-quality geomagnetic data, allows us such investigations even at inner Earth’s magnetospheric shell.
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13
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Hart ST, Dayeh MA, Reisenfeld DB, Janzen PH, McComas DJ, Allegrini F, Fuselier SA, Ogasawara K, Szalay JR, Funsten HO, Petrinec SM. Probing the Magnetosheath Boundaries Using Interstellar Boundary Explorer (IBEX) Orbital Encounters. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2021; 126:e2021JA029278. [PMID: 35865412 PMCID: PMC9286846 DOI: 10.1029/2021ja029278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/16/2021] [Accepted: 06/16/2021] [Indexed: 06/15/2023]
Abstract
Inside the magnetosheath, the IBEX-Hi energetic neutral atom (ENA) imager measures a distinct background count rate that is more than 10 times the typical heliospheric ENA emissions observed when IBEX is outside the magnetosheath. The source of this enhancement is magnetosheath ions of solar wind (SW) origin that deflect around the Earth's magnetopause (MP), scatter and neutralize from the anti-sunward part of the IBEX-Hi sunshade, and continue into the instrument as neutral atoms, behaving indistinguishably from ENAs emitted from distant plasma sources. While this background pollutes observations of outer heliospheric ENAs, it provides a clear signature of IBEX crossings over the magnetospheric boundaries. In this study, we investigate IBEX encounters with the magnetosheath boundaries using ∼8 yr of orbital data, and we determine the MP and bow shock (BS) locations derived from this background signal. We find 280 BS crossings from X GSE ∼ 11 Re to X GSE ∼ -36 Re and 241 MP crossings from X GSE ∼ 6 Re to X GSE ∼ -48 Re. We compare IBEX BS and MP crossing locations to those from IMP-8, Geotail, Cluster, Magion-4, ISEE, and Magnetospheric Multiscale Mission, and we find that IBEX crossing locations overlap with the BS and MP locations inferred from these other data sets. In this paper, we demonstrate how IBEX can be used to identify magnetosheath crossings, and extend boundary observations well past the terminator, thus further constraining future models of magnetosheath boundaries. Furthermore, we use the IBEX data set to show observational evidence of near-Earth magnetotail squeezing during periods of strong interplanetary magnetic field B y.
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Affiliation(s)
- S. T. Hart
- 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
| | | | - P. H. Janzen
- Department of Physics and AstronomyUniversity of MontanaMissoulaMTUSA
| | - D. J. McComas
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - F. Allegrini
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - S. A. Fuselier
- Southwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | | | - J. R. Szalay
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | | | - S. M. Petrinec
- Lockheed Martin Advanced Technology CenterPalo AltoCAUSA
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14
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Dayeh MA, Szalay JR, Ogasawara K, Fuselier SA, McComas DJ, Funsten HO, Petrinec SM, Schwadron NA, Zirnstein EJ. First Global Images of Ion Energization in the Terrestrial Foreshock by the Interstellar Boundary Explorer. GEOPHYSICAL RESEARCH LETTERS 2020; 47:e2020GL088188. [PMID: 33132458 PMCID: PMC7583366 DOI: 10.1029/2020gl088188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 06/17/2020] [Accepted: 07/19/2020] [Indexed: 06/11/2023]
Abstract
The Interstellar Boundary Explorer (IBEX) mission provides global energetic neutral atom (ENA) observations from the heliosphere and the Earth's magnetosphere, including spatial, temporal, and energy information. IBEX views the magnetosphere from the sides and almost always perpendicular to noon-midnight plane. We report the first ENA images of the energization process in the Earth's ion foreshock and magnetosheath regions. We show ENA flux and spectral images of the dayside magnetosphere with significant energization of ENA plasma sources (above ~2.7 keV) in the region magnetically connected to the Earth's bow shock (BS) in its quasi-parallel configuration of the interplanetary magnetic field (IMF). We also show that the ion energization increases gradually with decreasing IMF-BS angle, suggesting more efficient suprathermal ion acceleration deeper in the quasi-parallel foreshock.
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Affiliation(s)
- M. A. Dayeh
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - J. R. Szalay
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - K. Ogasawara
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
| | - S. A. Fuselier
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
- Department of Physics and AstronomyUniversity of Texas at San AntonioSan AntonioTXUSA
| | - D. J. McComas
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
| | - H. O. Funsten
- ISR DivisionLos Alamos National LaboratoryLos AlamosNMUSA
| | - S. M. Petrinec
- Lockheed Martin Advanced Technology CenterPalo AltoCAUSA
| | | | - E. J. Zirnstein
- Department of Astrophysical SciencesPrinceton UniversityPrincetonNJUSA
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15
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Bandyopadhyay R, Matthaeus WH, Parashar TN, Yang Y, Chasapis A, Giles BL, Gershman DJ, Pollock CJ, Russell CT, Strangeway RJ, Torbert RB, Moore TE, Burch JL. Statistics of Kinetic Dissipation in the Earth's Magnetosheath: MMS Observations. PHYSICAL REVIEW LETTERS 2020; 124:255101. [PMID: 32639771 DOI: 10.1103/physrevlett.124.255101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/03/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
A familiar problem in space and astrophysical plasmas is to understand how dissipation and heating occurs. These effects are often attributed to the cascade of broadband turbulence which transports energy from large scale reservoirs to small scale kinetic degrees of freedom. When collisions are infrequent, local thermodynamic equilibrium is not established. In this case the final stage of energy conversion becomes more complex than in the fluid case, and both pressure-dilatation and pressure strain interactions (Pi-D≡-Π_{ij}D_{ij}) become relevant and potentially important. Pi-D in plasma turbulence has been studied so far primarily using simulations. The present study provides a statistical analysis of Pi-D in the Earth's magnetosheath using the unique measurement capabilities of the Magnetospheric Multiscale (MMS) mission. We find that the statistics of Pi-D in this naturally occurring plasma environment exhibit strong resemblance to previously established fully kinetic simulations results. The conversion of energy is concentrated in space and occurs near intense current sheets, but not within them. This supports recent suggestions that the chain of energy transfer channels involves regional, rather than pointwise, correlations.
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Affiliation(s)
- Riddhi Bandyopadhyay
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - William H Matthaeus
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA and Bartol Research Institute, University of Delaware, Newark, Delaware 19716, USA
| | - Tulasi N Parashar
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
| | - Yan Yang
- Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Alexandros Chasapis
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, Colorado 80303, USA
| | - Barbara L Giles
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | | | | | | | | | - Roy B Torbert
- University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Thomas E Moore
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - James L Burch
- Southwest Research Institute, San Antonio, Texas 78238-5166, USA
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16
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Dimmock AP, Hietala H, Zou Y. Compiling Magnetosheath Statistical Data Sets Under Specific Solar Wind Conditions: Lessons Learnt From the Dayside Kinetic Southward IMF GEM Challenge. EARTH AND SPACE SCIENCE (HOBOKEN, N.J.) 2020; 7:e2020EA001095. [PMID: 32715028 PMCID: PMC7375150 DOI: 10.1029/2020ea001095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/14/2020] [Accepted: 02/27/2020] [Indexed: 06/11/2023]
Abstract
The Geospace Environmental Modelling (GEM) community offers a framework for collaborations between modelers, observers, and theoreticians in the form of regular challenges. In many cases, these challenges involve model-data comparisons to provide wider context to observations or validate model results. To perform meaningful comparisons, a statistical approach is often adopted, which requires the extraction of a large number of measurements from a specific region. However, in complex regions such as the magnetosheath, compiling these data can be difficult. Here, we provide the statistical context of compiling statistical data for the southward IMF GEM challenge initiated by the "Dayside Kinetic Processes in Global Solar Wind-Magnetosphere Interaction" focus group. It is shown that matching very specific upstream conditions can severely impact the statistical data if limits are imposed on several solar wind parameters. We suggest that future studies that wish to compare simulations and/or single events to statistical data should carefully consider at an early stage the availability of data in context with the upstream criteria. We also demonstrate the importance of how specific IMF conditions are defined, the chosen spacecraft, the region of interest, and how regions are identified automatically. The lessons learnt in this study are of wide context to many future studies as well as GEM challenges. The results also highlight the issue where a global statistical perspective has to be balanced with its relevance to more-extreme, less-frequent individual events, which is typically the case in the field of space weather.
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Affiliation(s)
| | - H. Hietala
- Blackett LaboratoryImperial College LondonLondonUK
- Department of Physics and AstronomyUniversity of TurkuTurkuFinland
- Department of Earth, Planetary, and Space SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Y. Zou
- Department of Space ScienceThe University of Alabama in HuntsvilleHuntsvilleALUSA
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17
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Heinemann SG, Temmer M, Farrugia CJ, Dissauer K, Kay C, Wiegelmann T, Dumbović M, Veronig AM, Podladchikova T, Hofmeister SJ, Lugaz N, Carcaboso F. CME-HSS Interaction and Characteristics Tracked from Sun to Earth. SOLAR PHYSICS 2019; 294:121. [PMID: 31929659 PMCID: PMC6936343 DOI: 10.1007/s11207-019-1515-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 08/27/2019] [Indexed: 06/10/2023]
Abstract
In a thorough study, we investigate the origin of a remarkable plasma and magnetic field configuration observed in situ on June 22, 2011, near L1, which appears to be a magnetic ejecta (ME) and a shock signature engulfed by a solar wind high-speed stream (HSS). We identify the signatures as an Earth-directed coronal mass ejection (CME), associated with a C7.7 flare on June 21, 2011, and its interaction with a HSS, which emanates from a coronal hole (CH) close to the launch site of the CME. The results indicate that the major interaction between the CME and the HSS starts at a height of 1.3 R ⊙ up to 3 R ⊙ . Over that distance range, the CME undergoes a strong north-eastward deflection of at least 30 ∘ due to the open magnetic field configuration of the CH. We perform a comprehensive analysis for the CME-HSS event using multi-viewpoint data (from the Solar TErrestrial RElations Observatories, the Solar and Heliospheric Observatory and the Solar Dynamics Observatory), and combined modeling efforts (nonlinear force-free field modeling, Graduated Cylindrical Shell CME modeling, and the Forecasting a CME's Altered Trajectory - ForeCAT model). We aim at better understanding its early evolution and interaction process as well as its interplanetary propagation and related in situ signatures, and finally the resulting impact on the Earth's magnetosphere.
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Affiliation(s)
- Stephan G. Heinemann
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Manuela Temmer
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Charles J. Farrugia
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Morse Hall, 8 College Road, Durham, NH 03824-3525 USA
| | - Karin Dissauer
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Christina Kay
- Solar Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD USA
- Dept. of Physics, The Catholic University of America, Washington, DC USA
| | - Thomas Wiegelmann
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Mateja Dumbović
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Astrid M. Veronig
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
- Kanzelhöhe Observatory for Solar and Environmental Research, University of Graz, 9521 Treffen, Austria
| | - Tatiana Podladchikova
- Skolkovo Institute of Science and Technology Skolkovo Innovation Center, Building 3, Moscow, 143026 Russia
| | - Stefan J. Hofmeister
- Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Noé Lugaz
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Morse Hall, 8 College Road, Durham, NH 03824-3525 USA
| | - Fernando Carcaboso
- Dpto. de Física y Matemáticas, Universidad de Alcalá, 28805 Alcalá de Henares, Madrid, Spain
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18
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Pezzopane M, Del Corpo A, Piersanti M, Cesaroni C, Pignalberi A, Di Matteo S, Spogli L, Vellante M, Heilig B. On some features characterizing the plasmasphere-magnetosphere-ionosphere system during the geomagnetic storm of 27 May 2017. EARTH, PLANETS, AND SPACE : EPS 2019; 71:77. [PMID: 31402843 PMCID: PMC6647577 DOI: 10.1186/s40623-019-1056-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 07/02/2019] [Indexed: 06/10/2023]
Abstract
This paper presents how the magnetosphere-plasmasphere-ionosphere system was affected as a whole during the geomagnetic storm peaking on 27 May 2017. The interplanetary conditions, the magnetospheric response in terms of the magnetopause motion, and the ionospheric current flow pattern were investigated using data, respectively, from the WIND spacecraft, from GOES15, GOES13, THEMIS E, THEMIS D and THEMIS A satellites and from the INTERMAGNET magnetometer array. The main objective of the work is to investigate the plasmaspheric dynamics under disturbed conditions and its possible relation to the ionospheric one; to reach this goal, the equatorial plasma mass densities derived from geomagnetic field line resonance observations at the European quasi-Meridional Magnetometer Array (EMMA) and total electron content values obtained through three GPS receivers close to EMMA were jointly considered. Despite the complexity of physical mechanisms behind them, we found a similarity between the ionospheric and plasmaspheric characteristic recovery times. Specifically, the ionospheric characteristic time turned out to be ~ 1.5 days, ~ 2 days and ~ 3.1 days, respectively, at L ~ 3, L ~ 4 and L ~ 5, while the plasmaspheric one, for similar L values, ranged from ~ 1 day to more than 4 days.
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Affiliation(s)
- Michael Pezzopane
- Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome, Italy
| | - Afredo Del Corpo
- Department of Physical and Chemical Sciences, University of L’Aquila, Via Vetoio, 67100 L’Aquila, Italy
| | - Mirko Piersanti
- National Institute of Nuclear Physics, University of “Tor Vergata”, Via della ricerca scientifica 1, 00133 Rome, Italy
| | - Claudio Cesaroni
- Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome, Italy
| | - Alessio Pignalberi
- Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome, Italy
| | - Simone Di Matteo
- Department of Physical and Chemical Sciences, University of L’Aquila, Via Vetoio, 67100 L’Aquila, Italy
| | - Luca Spogli
- Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome, Italy
- SpacEarth Technology, Via di Vigna Murata 605, 00143 Rome, Italy
| | - Massimo Vellante
- Department of Physical and Chemical Sciences, University of L’Aquila, Via Vetoio, 67100 L’Aquila, Italy
| | - Balazs Heilig
- Mining and Geological Survey of Hungary, Columbus Street 17-23, Budapest, 1145 Hungary
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19
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Archer MO, Hietala H, Hartinger MD, Plaschke F, Angelopoulos V. Direct observations of a surface eigenmode of the dayside magnetopause. Nat Commun 2019; 10:615. [PMID: 30755606 PMCID: PMC6372605 DOI: 10.1038/s41467-018-08134-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 12/11/2018] [Indexed: 11/26/2022] Open
Abstract
The abrupt boundary between a magnetosphere and the surrounding plasma, the magnetopause, has long been known to support surface waves. It was proposed that impulses acting on the boundary might lead to a trapping of these waves on the dayside by the ionosphere, resulting in a standing wave or eigenmode of the magnetopause surface. No direct observational evidence of this has been found to date and searches for indirect evidence have proved inconclusive, leading to speculation that this mechanism might not occur. By using fortuitous multipoint spacecraft observations during a rare isolated fast plasma jet impinging on the boundary, here we show that the resulting magnetopause motion and magnetospheric ultra-low frequency waves at well-defined frequencies are in agreement with and can only be explained by the magnetopause surface eigenmode. We therefore show through direct observations that this mechanism, which should impact upon the magnetospheric system globally, does in fact occur. Surface waves on the boundary between a magnetosphere and the surrounding plasma might get trapped by the ionosphere forming an eigenmode. Here, Archer et al. show direct observations of this proposed mechanism at Earth’s magnetosphere by analyzing the response to an isolated fast plasma jet detected by the THEMIS satellites.
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Affiliation(s)
- M O Archer
- School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London, E1 4NS, UK. .,Space and Atmospheric Physics Group, Department of Physics, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
| | - H Hietala
- Department of Earth, Planetary and Space Sciences, University of California, Los Angeles, 595 Charles Young Drive East CA, 90095-1567, USA.,Space Research Laboratory, Department of Physics and Astronomy, University of Turku, 20500, Turku, Finland
| | - M D Hartinger
- Space Science Institute, 4750 Walnut St Suite 205, Boulder, CO, 80301, USA.,Department of Electrical and Computer Engineering, Virginia Tech, Perry St, Blacksburg, VA, 24060, USA
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstraße 6, 8042, Graz, Austria
| | - V Angelopoulos
- Department of Earth, Planetary and Space Sciences, University of California, Los Angeles, 595 Charles Young Drive East CA, 90095-1567, USA
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20
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Magnetospheric Multiscale Observations of Turbulence in the Magnetosheath on Kinetic Scales. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/2041-8213/aad9a8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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21
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Murphy KR, Inglis AR, Sibeck DG, Rae IJ, Watt CEJ, Silveira M, Plaschke F, Claudepierre SG, Nakamura R. Determining the Mode, Frequency, and Azimuthal Wave Number of ULF Waves During a HSS and Moderate Geomagnetic Storm. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2018; 123:6457-6477. [PMID: 31681521 PMCID: PMC6813628 DOI: 10.1029/2017ja024877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 06/10/2023]
Abstract
Ultralow frequency (ULF) waves play a fundamental role in the dynamics of the inner magnetosphere and outer radiation belt during geomagnetic storms. Broadband ULF wave power can transport energetic electrons via radial diffusion, and discrete ULF wave power can energize electrons through a resonant interaction. Using observations from the Magnetospheric Multiscale mission, we characterize the evolution of ULF waves during a high-speed solar wind stream (HSS) and moderate geomagnetic storm while there is an enhancement of the outer radiation belt. The Automated Flare Inference of Oscillations code is used to distinguish discrete ULF wave power from broadband wave power during the HSS. During periods of discrete wave power and utilizing the close separation of the Magnetospheric Multiscale spacecraft, we estimate the toroidal mode ULF azimuthal wave number throughout the geomagnetic storm. We concentrate on the toroidal mode as the HSS compresses the dayside magnetosphere resulting in an asymmetric magnetic field topology where toroidal mode waves can interact with energetic electrons. Analysis of the mode structure and wave numbers demonstrates that the generation of the observed ULF waves is a combination of externally driven waves, via the Kelvin-Helmholtz instability, and internally driven waves, via unstable ion distributions. Further analysis of the periods and toroidal azimuthal wave numbers suggests that these waves can couple with the core electron radiation belt population via the drift resonance during the storm. The azimuthal wave number and structure of ULF wave power (broadband or discrete) have important implications for the inner magnetospheric and radiation belt dynamics.
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Affiliation(s)
- Kyle R. Murphy
- Department of AstronomyUniversity of MarylandCollege ParkMDUSA
| | | | - David G. Sibeck
- NASA Goddard Space Flight Center, Space Weather Laboratory (674)GreenbeltMDUSA
| | - I. Jonathan Rae
- Department of Space and Climate Physics, Mullard Space Science LaboratoryUniversity College LondonLondonUK
| | | | | | | | | | - Rumi Nakamura
- Space Research InstituteAustrian Academy of SciencesGrazAustria
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22
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Zhang Q, Lockwood M, Foster JC, Zong Q, Dunlop MW, Zhang S, Moen J, Zhang B. Observations of the step-like accelerating processes of cold ions in the reconnection layer at the dayside magnetopause. Sci Bull (Beijing) 2018; 63:31-37. [PMID: 36658915 DOI: 10.1016/j.scib.2018.01.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/21/2017] [Accepted: 12/22/2017] [Indexed: 01/21/2023]
Abstract
Cold ions of plasmaspheric origin have been observed to abundantly appear in the magnetospheric side of the Earth's magnetopause. These cold ions could affect the magnetic reconnection processes at the magnetopause by changing the Alfvén velocity and the reconnection rate, while they could also be heated in the reconnection layer during the ongoing reconnections. We report in situ observations from a partially crossing of a reconnection layer near the subsolar magnetopause. During this crossing, step-like accelerating processes of the cold ions were clearly observed, suggesting that the inflow cold ions may be separately accelerated by the rotation discontinuity and slow shock inside the reconnection layer.
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Affiliation(s)
- Qinghe Zhang
- Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai 264209, China.
| | - Michael Lockwood
- Department of Meteorology, University of Reading, Reading RG6 6BB, UK
| | | | - Qiugang Zong
- School of Earth and Space Sciences, Peking University, Beijing 100087, China
| | - Malcolm W Dunlop
- Space Sciences Division, SSTD, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | | | - Jøran Moen
- Department of Physics, University of Oslo, Blindern 0316, Oslo, Norway
| | - Beichen Zhang
- SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai 200136, China
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23
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Nakamura TKM, Hasegawa H, Daughton W, Eriksson S, Li WY, Nakamura R. Turbulent mass transfer caused by vortex induced reconnection in collisionless magnetospheric plasmas. Nat Commun 2017; 8:1582. [PMID: 29150662 PMCID: PMC5693928 DOI: 10.1038/s41467-017-01579-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 10/01/2017] [Indexed: 11/09/2022] Open
Abstract
Magnetic reconnection is believed to be the main driver to transport solar wind into the Earth's magnetosphere when the magnetopause features a large magnetic shear. However, even when the magnetic shear is too small for spontaneous reconnection, the Kelvin-Helmholtz instability driven by a super-Alfvénic velocity shear is expected to facilitate the transport. Although previous kinetic simulations have demonstrated that the non-linear vortex flows from the Kelvin-Helmholtz instability gives rise to vortex-induced reconnection and resulting plasma transport, the system sizes of these simulations were too small to allow the reconnection to evolve much beyond the electron scale as recently observed by the Magnetospheric Multiscale (MMS) spacecraft. Here, based on a large-scale kinetic simulation and its comparison with MMS observations, we show for the first time that ion-scale jets from vortex-induced reconnection rapidly decay through self-generated turbulence, leading to a mass transfer rate nearly one order higher than previous expectations for the Kelvin-Helmholtz instability.
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Affiliation(s)
- T K M Nakamura
- Space Research Institute, Austrian Academy of Sciences, 8010, Graz, Austria.
| | - H Hasegawa
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, 252-5210, Japan
| | - W Daughton
- Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - S Eriksson
- Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, CO, 80303, USA
| | - W Y Li
- Swedish Institute of Space Physics, SE751-21, Uppsala, Sweden.,State Key Laboratory of Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing, 100190, China
| | - R Nakamura
- Space Research Institute, Austrian Academy of Sciences, 8010, Graz, Austria
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24
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Dimmock AP, Nykyri K, Osmane A, Karimabadi H, Pulkkinen TI. Dawn-Dusk Asymmetries of the Earth's Dayside Magnetosheath in the Magnetosheath Interplanetary Medium Reference Frame. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/9781119216346.ch5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Affiliation(s)
- A. P. Dimmock
- School of Electrical Engineering; Aalto University; Espoo Finland
| | - K. Nykyri
- Department of Physical Sciences; Embry-Riddle Aeronautical University; Daytona Beach Florida USA
| | - A. Osmane
- School of Electrical Engineering; Aalto University; Espoo Finland
| | - H. Karimabadi
- University of California; San Diego, La Jolla California
- SciberQuest, Inc.; Del Mar California USA
| | - T. I. Pulkkinen
- School of Electrical Engineering; Aalto University; Espoo Finland
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25
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Lugaz N, Farrugia CJ, Winslow RM, Al-Haddad N, Kilpua EKJ, Riley P. Factors Affecting the Geo-effectiveness of Shocks and Sheaths at 1 AU. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2016; 121:10861-10879. [PMID: 29629250 PMCID: PMC5882492 DOI: 10.1002/2016ja023100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We identify all fast-mode forward shocks, whose sheath regions resulted in a moderate (56 cases) or intense (38 cases) geomagnetic storm during 18.5 years from January 1997 to June 2015. We study their main properties, interplanetary causes and geo-effects. We find that half (49/94) such shocks are associated with interacting coronal mass ejections (CMEs), as they are either shocks propagating into a preceding CME (35 cases) or a shock propagating into the sheath region of a preceding shock (14 cases). About half (22/45) of the shocks driven by isolated transients and which have geo-effective sheaths compress pre-existing southward Bz . Most of the remaining sheaths appear to have planar structures with southward magnetic fields, including some with planar structures consistent with field line draping ahead of the magnetic ejecta. A typical (median) geo-effective shock-sheath structure drives a geomagnetic storm with peak Dst of -88 nT, pushes the subsolar magnetopause location to 6.3 RE, i.e. below geosynchronous orbit and is associated with substorms with a peak AL-index of -1350 nT. There are some important differences between sheaths associated with CME-CME interaction (stronger storms) and those associated with isolated CMEs (stronger compression of the magnetosphere). We detail six case studies of different types of geo-effective shock-sheaths, as well as two events for which there was no geomagnetic storm but other magnetospheric effects. Finally, we discuss our results in terms of space weather forecasting, and potential effects on Earth's radiation belts.
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Affiliation(s)
- N. Lugaz
- Space Science Center, University of New Hampshire, Durham, NH, USA
- Department of Physics, University of New Hampshire, Durham, NH, USA
| | - C. J. Farrugia
- Space Science Center, University of New Hampshire, Durham, NH, USA
- Department of Physics, University of New Hampshire, Durham, NH, USA
| | - R. M. Winslow
- Space Science Center, University of New Hampshire, Durham, NH, USA
| | - N. Al-Haddad
- Department of Physics, University of New Hampshire, Durham, NH, USA
- Institute for Astrophysics and Computational Sciences, Catholic University of America, Washington, DC, USA
| | - E. K. J. Kilpua
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - P. Riley
- Predictive Sciences Inc., San Diego, CA, USA
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26
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Lugaz N, Farrugia CJ, Huang CL, Winslow RM, Spence HE, Schwadron NA. Earth's magnetosphere and outer radiation belt under sub-Alfvénic solar wind. Nat Commun 2016; 7:13001. [PMID: 27694887 PMCID: PMC5063966 DOI: 10.1038/ncomms13001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 08/19/2016] [Indexed: 12/04/2022] Open
Abstract
The interaction between Earth's magnetic field and the solar wind results in the formation of a collisionless bow shock 60,000–100,000 km upstream of our planet, as long as the solar wind fast magnetosonic Mach (hereafter Mach) number exceeds unity. Here, we present one of those extremely rare instances, when the solar wind Mach number reached steady values <1 for several hours on 17 January 2013. Simultaneous measurements by more than ten spacecraft in the near-Earth environment reveal the evanescence of the bow shock, the sunward motion of the magnetopause and the extremely rapid and intense loss of electrons in the outer radiation belt. This study allows us to directly observe the state of the inner magnetosphere, including the radiation belts during a type of solar wind-magnetosphere coupling which is unusual for planets in our solar system but may be common for close-in extrasolar planets. The interaction between the Earth's magnetic field and the solar wind results in the formation of a collisionless bow shock. Here, the authors study an even in which the solar wind Mach number remained steadily below one, leading to the evanescence of the bow shock and loss of electrons in the outer belts.
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Affiliation(s)
- Noé Lugaz
- Space Science Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, 8 College Road, Durham, New Hampshire 03824, USA.,Department of Physics, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Charles J Farrugia
- Space Science Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, 8 College Road, Durham, New Hampshire 03824, USA.,Department of Physics, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Chia-Lin Huang
- Space Science Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, 8 College Road, Durham, New Hampshire 03824, USA.,Department of Physics, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Reka M Winslow
- Space Science Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, 8 College Road, Durham, New Hampshire 03824, USA
| | - Harlan E Spence
- Space Science Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, 8 College Road, Durham, New Hampshire 03824, USA.,Department of Physics, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Nathan A Schwadron
- Space Science Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, 8 College Road, Durham, New Hampshire 03824, USA.,Department of Physics, University of New Hampshire, Durham, New Hampshire 03824, USA
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27
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Baker DN, Jaynes AN, Kanekal SG, Foster JC, Erickson PJ, Fennell JF, Blake JB, Zhao H, Li X, Elkington SR, Henderson MG, Reeves GD, Spence HE, Kletzing CA, Wygant JR. Highly relativistic radiation belt electron acceleration, transport, and loss: Large solar storm events of March and June 2015. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2016; 121:6647-6660. [PMID: 27867796 PMCID: PMC5101849 DOI: 10.1002/2016ja022502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 06/02/2016] [Accepted: 06/27/2016] [Indexed: 05/28/2023]
Abstract
Two of the largest geomagnetic storms of the last decade were witnessed in 2015. On 17 March 2015, a coronal mass ejection-driven event occurred with a Dst (storm time ring current index) value reaching -223 nT. On 22 June 2015 another strong storm (Dst reaching -204 nT) was recorded. These two storms each produced almost total loss of radiation belt high-energy (E ≳ 1 MeV) electron fluxes. Following the dropouts of radiation belt fluxes there were complex and rather remarkable recoveries of the electrons extending up to nearly 10 MeV in kinetic energy. The energized outer zone electrons showed a rich variety of pitch angle features including strong "butterfly" distributions with deep minima in flux at α = 90°. However, despite strong driving of outer zone earthward radial diffusion in these storms, the previously reported "impenetrable barrier" at L ≈ 2.8 was pushed inward, but not significantly breached, and no E ≳ 2.0 MeV electrons were seen to pass through the radiation belt slot region to reach the inner Van Allen zone. Overall, these intense storms show a wealth of novel features of acceleration, transport, and loss that are demonstrated in the present detailed analysis.
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Affiliation(s)
- D. N. Baker
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderColoradoUSA
| | - A. N. Jaynes
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderColoradoUSA
| | | | - J. C. Foster
- MIT Haystack ObservatoryWestfordMassachusettsUSA
| | | | | | - J. B. Blake
- The Aerospace CorporationLos AngelesCaliforniaUSA
| | - H. Zhao
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderColoradoUSA
| | - X. Li
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderColoradoUSA
| | - S. R. Elkington
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderColoradoUSA
| | | | - G. D. Reeves
- Los Alamos National LaboratoryLos AlamosNew MexicoUSA
| | - H. E. Spence
- Institute for the Study of Earth, Oceans, and SpaceUniversity of New HampshireDurhamNew HampshireUSA
| | - C. A. Kletzing
- Department of Physics and AstronomyUniversity of IowaIowa CityIowaUSA
| | - J. R. Wygant
- Department of Physics and AstronomyUniversity of Minnesota, Twin CitiesMinneapolisMinnesotaUSA
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28
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Antonova EE, Vorobjev VG, Kirpichev IP, Yagodkina OI, Stepanova MV. Problems with mapping the auroral oval and magnetospheric substorms. EARTH, PLANETS, AND SPACE : EPS 2015; 67:166. [PMID: 27656099 PMCID: PMC5012350 DOI: 10.1186/s40623-015-0336-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 10/01/2015] [Indexed: 06/06/2023]
Abstract
Accurate mapping of the auroral oval into the equatorial plane is critical for the analysis of aurora and substorm dynamics. Comparison of ion pressure values measured at low altitudes by Defense Meteorological Satellite Program (DMSP) satellites during their crossings of the auroral oval, with plasma pressure values obtained at the equatorial plane from Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellite measurements, indicates that the main part of the auroral oval maps into the equatorial plane at distances between 6 and 12 Earth radii. On the nightside, this region is generally considered to be a part of the plasma sheet. However, our studies suggest that this region could form part of the plasma ring surrounding the Earth. We discuss the possibility of using the results found here to explain the ring-like shape of the auroral oval, the location of the injection boundary inside the magnetosphere near the geostationary orbit, presence of quiet auroral arcs in the auroral oval despite the constantly high level of turbulence observed in the plasma sheet, and some features of the onset of substorm expansion.
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Affiliation(s)
- E. E. Antonova
- Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia
| | - V. G. Vorobjev
- Polar Geophysical Institute, Apatity, Murmansk Region Russia
| | | | - O. I. Yagodkina
- Polar Geophysical Institute, Apatity, Murmansk Region Russia
| | - M. V. Stepanova
- Physics Department, Science Faculty, Universidad de Santiago de Chile, Santiago, Chile
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29
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Korth H, Tsyganenko NA, Johnson CL, Philpott LC, Anderson BJ, Al Asad MM, Solomon SC, McNutt RL. Modular model for Mercury's magnetospheric magnetic field confined within the average observed magnetopause. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2015; 120:4503-4518. [PMID: 27656335 PMCID: PMC5014231 DOI: 10.1002/2015ja021022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 04/13/2015] [Accepted: 05/07/2015] [Indexed: 06/01/2023]
Abstract
Accurate knowledge of Mercury's magnetospheric magnetic field is required to understand the sources of the planet's internal field. We present the first model of Mercury's magnetospheric magnetic field confined within a magnetopause shape derived from Magnetometer observations by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft. The field of internal origin is approximated by a dipole of magnitude 190 nT RM3, where RM is Mercury's radius, offset northward by 479 km along the spin axis. External field sources include currents flowing on the magnetopause boundary and in the cross-tail current sheet. The cross-tail current is described by a disk-shaped current near the planet and a sheet current at larger (≳ 5 RM ) antisunward distances. The tail currents are constrained by minimizing the root-mean-square (RMS) residual between the model and the magnetic field observed within the magnetosphere. The magnetopause current contributions are derived by shielding the field of each module external to the magnetopause by minimizing the RMS normal component of the magnetic field at the magnetopause. The new model yields improvements over the previously developed paraboloid model in regions that are close to the magnetopause and the nightside magnetic equatorial plane. Magnetic field residuals remain that are distributed systematically over large areas and vary monotonically with magnetic activity. Further advances in empirical descriptions of Mercury's magnetospheric external field will need to account for the dependence of the tail and magnetopause currents on magnetic activity and additional sources within the magnetosphere associated with Birkeland currents and plasma distributions near the dayside magnetopause.
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Affiliation(s)
- Haje Korth
- The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA
| | - Nikolai A Tsyganenko
- Institute and Faculty of Physics Saint Petersburg State University Saint Petersburg Russia
| | - Catherine L Johnson
- Department of Earth, Ocean and Atmospheric Sciences University of British Columbia Vancouver British Columbia Canada; Planetary Science Institute Tucson Arizona USA
| | - Lydia C Philpott
- Department of Earth, Ocean and Atmospheric Sciences University of British Columbia Vancouver British Columbia Canada
| | - Brian J Anderson
- The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA
| | - Manar M Al Asad
- Department of Earth, Ocean and Atmospheric Sciences University of British Columbia Vancouver British Columbia Canada; Saudi Aramco Dharan Saudi Arabia
| | - Sean C Solomon
- Department of Terrestrial Magnetism Carnegie Institution of Washington Washington District of Columbia USA; Lamont-Doherty Earth Observatory Columbia University Palisades New York USA
| | - Ralph L McNutt
- The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USA
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30
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Ukhorskiy AY, Sitnov MI, Millan RM, Kress BT, Fennell JF, Claudepierre SG, Barnes RJ. Global storm time depletion of the outer electron belt. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2015; 120:2543-2556. [PMID: 27656334 PMCID: PMC5014085 DOI: 10.1002/2014ja020645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 03/04/2015] [Accepted: 03/04/2015] [Indexed: 06/06/2023]
Abstract
The outer radiation belt consists of relativistic (>0.5 MeV) electrons trapped on closed trajectories around Earth where the magnetic field is nearly dipolar. During increased geomagnetic activity, electron intensities in the belt can vary by orders of magnitude at different spatial and temporal scales. The main phase of geomagnetic storms often produces deep depletions of electron intensities over broad regions of the outer belt. Previous studies identified three possible processes that can contribute to the main-phase depletions: adiabatic inflation of electron drift orbits caused by the ring current growth, electron loss into the atmosphere, and electron escape through the magnetopause boundary. In this paper we investigate the relative importance of the adiabatic effect and magnetopause loss to the rapid depletion of the outer belt observed at the Van Allen Probes spacecraft during the main phase of 17 March 2013 storm. The intensities of >1 MeV electrons were depleted by more than an order of magnitude over the entire radial extent of the belt in less than 6 h after the sudden storm commencement. For the analysis we used three-dimensional test particle simulations of global evolution of the outer belt in the Tsyganenko-Sitnov (TS07D) magnetic field model with an inductive electric field. Comparison of the simulation results with electron measurements from the Magnetic Electron Ion Spectrometer experiment shows that magnetopause loss accounts for most of the observed depletion at L>5, while at lower L shells the depletion is adiabatic. Both magnetopause loss and the adiabatic effect are controlled by the change in global configuration of the magnetic field due to storm time development of the ring current; a simulation of electron evolution without a ring current produces a much weaker depletion.
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Affiliation(s)
- A. Y. Ukhorskiy
- Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - M. I. Sitnov
- Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - R. M. Millan
- Department of Physics and AstronomyDartmouth CollegeHanoverNew HampshireUSA
| | - B. T. Kress
- Cooperative Institute for Research in Environmental SciencesUniversity of Colorado at BoulderBoulderColoradoUSA
| | | | | | - R. J. Barnes
- Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
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31
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Rapid local acceleration of relativistic radiation-belt electrons by magnetospheric chorus. Nature 2014; 504:411-4. [PMID: 24352287 DOI: 10.1038/nature12889] [Citation(s) in RCA: 517] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 11/18/2013] [Indexed: 11/09/2022]
Abstract
Recent analysis of satellite data obtained during the 9 October 2012 geomagnetic storm identified the development of peaks in electron phase space density, which are compelling evidence for local electron acceleration in the heart of the outer radiation belt, but are inconsistent with acceleration by inward radial diffusive transport. However, the precise physical mechanism responsible for the acceleration on 9 October was not identified. Previous modelling has indicated that a magnetospheric electromagnetic emission known as chorus could be a potential candidate for local electron acceleration, but a definitive resolution of the importance of chorus for radiation-belt acceleration was not possible because of limitations in the energy range and resolution of previous electron observations and the lack of a dynamic global wave model. Here we report high-resolution electron observations obtained during the 9 October storm and demonstrate, using a two-dimensional simulation performed with a recently developed time-varying data-driven model, that chorus scattering explains the temporal evolution of both the energy and angular distribution of the observed relativistic electron flux increase. Our detailed modelling demonstrates the remarkable efficiency of wave acceleration in the Earth's outer radiation belt, and the results presented have potential application to Jupiter, Saturn and other magnetized astrophysical objects.
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32
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Hietala H, Plaschke F. On the generation of magnetosheath high-speed jets by bow shock ripples. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2013; 118:7237-7245. [PMID: 26167426 PMCID: PMC4497490 DOI: 10.1002/2013ja019172] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 09/05/2013] [Accepted: 11/02/2013] [Indexed: 06/04/2023]
Abstract
[1]The terrestrial magnetosheath is embedded with coherent high-speed jets of about 1RE in scale, predominantly during quasi-radial interplanetary magnetic field (IMF). When these high dynamic pressure (Pdyn) jets hit the magnetopause, they cause large indentations and further magnetospheric effects. The source of these jets has remained controversial. One of the proposed mechanisms is based on ripples of the quasi-parallel bow shock. In this paper, we combine for the first time, 4 years of subsolar magnetosheath observations from the Time History of Events and Macroscale Interactions during Substorms mission and corresponding NASA/OMNI solar wind conditions with model calculations of a rippled bow shock. Concentrating on the magnetosheath close to the shock during intervals when the angle between the IMF and the Sun-Earth line was small, we find that (1) 97% of the observed jets can be produced by local ripples of the shock under the observed upstream conditions; (2) the coherent jets form a significant fraction of the high Pdyn tail of the magnetosheath flow distribution; (3) the magnetosheath Pdyn distribution matches the flow from a bow shock with ripples that have a dominant amplitude to wavelength ratio of about 9% (∼0.1RE/1RE) and are present ∼12% of the time at any given location.
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Affiliation(s)
- H Hietala
- Blackett Laboratory, Imperial College London London, UK
| | - F Plaschke
- Space Research Institute, Austrian Academy of Sciences Graz, Austria
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33
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Walsh BM, Sibeck DG, Wang Y, Fairfield DH. Dawn-dusk asymmetries in the Earth's magnetosheath. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012ja018240] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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34
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Shprits Y, Daae M, Ni B. Statistical analysis of phase space density buildups and dropouts. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011ja016939] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Li X, Temerin M, Baker DN, Reeves GD. Behavior of MeV electrons at geosynchronous orbit during last two solar cycles. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011ja016934] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- X. Li
- Department of Aerospace Engineering Sciences, Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
| | | | - D. N. Baker
- Department of Astrophysics and Planetary Sciences, Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
| | - G. D. Reeves
- Space Science and Applications Group; Los Alamos National Laboratory; Los Alamos New Mexico USA
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36
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Fu HS, Cao JB, Yang B, Lu HY. Electron loss and acceleration during storm time: The contribution of wave-particle interaction, radial diffusion, and transport processes. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011ja016672] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- H. S. Fu
- School of Astronautics, Space Science Institute; Beihang University; Beijing China
- Swedish Institute of Space Physics; Uppsala Sweden
| | - J. B. Cao
- School of Astronautics, Space Science Institute; Beihang University; Beijing China
| | - B. Yang
- Institute of Space Physics and Applied Technology; Peking University; Beijing China
| | - H. Y. Lu
- School of Astronautics, Space Science Institute; Beihang University; Beijing China
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37
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Lu JY, Liu ZQ, Kabin K, Zhao MX, Liu DD, Zhou Q, Xiao Y. Three dimensional shape of the magnetopause: Global MHD results. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010ja016418] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- J. Y. Lu
- National Center for Space Weather; China Meteorology Administration; Beijing China
| | - Z.-Q. Liu
- Chinese Academy of Meteorological Science; Graduate University of Chinese Academy of Science; Beijing China
| | - K. Kabin
- Department of Physics; Royal Military College of Canada; Kingston, Ontario Canada
| | - M. X. Zhao
- National Center for Space Weather; China Meteorology Administration; Beijing China
| | - D. D. Liu
- National Center for Space Weather; China Meteorology Administration; Beijing China
| | - Q. Zhou
- Department of Geophysics and Geomatics; China University of Geoscience; Wuhan China
| | - Y. Xiao
- Department of Mathematics and Information Engineering; Puyang Vocational and Technical College; Puyang, HeNan China
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38
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Lin RL, Zhang XX, Liu SQ, Wang YL, Gong JC. A three-dimensional asymmetric magnetopause model. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009ja014235] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- R. L. Lin
- Center for Space Science and Applied Research; Chinese Academy of Sciences; Beijing China
- Graduate University of Chinese Academy of Sciences; Beijing China
| | - X. X. Zhang
- National Center for Space Weather; China Meteorological Administration; Beijing China
| | - S. Q. Liu
- Center for Space Science and Applied Research; Chinese Academy of Sciences; Beijing China
| | - Y. L. Wang
- NASA Goddard Space Flight Center; Greenbelt Maryland USA
| | - J. C. Gong
- Center for Space Science and Applied Research; Chinese Academy of Sciences; Beijing China
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39
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Kim KC, Lee DY, Kim HJ, Lee ES, Choi CR. Numerical estimates of drift loss and Dst effect for outer radiation belt relativistic electrons with arbitrary pitch angle. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009ja014523] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Kyung Chan Kim
- Department of Astronomy and Space Science; Chungbuk National University; Chungbuk South Korea
| | - D.-Y. Lee
- Department of Astronomy and Space Science; Chungbuk National University; Chungbuk South Korea
| | - H.-J. Kim
- Department of Atmospheric Sciences; University of California; Los Angeles California USA
| | - E. S. Lee
- Space Sciences Laboratory; University of California; Berkeley USA
| | - C. R. Choi
- Department of Physics; Korea Advanced Institute of Science and Technology; Daejeon South Korea
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40
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Lin R, Zhang X, Liu S, Wang Y, Gong J. Comparison of a new model with previous models for the low-latitude magnetopause size and shape. CHINESE SCIENCE BULLETIN-CHINESE 2009. [DOI: 10.1007/s11434-009-0533-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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41
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Ohtani S, Miyoshi Y, Singer HJ, Weygand JM. On the loss of relativistic electrons at geosynchronous altitude: Its dependence on magnetic configurations and external conditions. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008ja013391] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- S. Ohtani
- Johns Hopkins University Applied Physics Laboratory; Laurel Maryland USA
| | - Y. Miyoshi
- Solar-Terrestrial Environment Laboratory; Nagoya University; Nagoya Japan
| | - H. J. Singer
- Space Weather Prediction Center; NOAA; Boulder Colorado USA
| | - J. M. Weygand
- Institute of Geophysics and Planetary Physics; University of California; Los Angeles California USA
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42
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Alexeev II, Belenkaya ES, Yu. Bobrovnikov S, Slavin JA, Sarantos M. Paraboloid model of Mercury's magnetosphere. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008ja013368] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- I. I. Alexeev
- Institute of Nuclear Physics; Lomonosov Moscow State University, Leninskie Gory; Moscow Russia
| | - E. S. Belenkaya
- Institute of Nuclear Physics; Lomonosov Moscow State University, Leninskie Gory; Moscow Russia
| | - S. Yu. Bobrovnikov
- Institute of Nuclear Physics; Lomonosov Moscow State University, Leninskie Gory; Moscow Russia
| | - J. A. Slavin
- Heliophysics Science Division; NASA GSFC; Greenbelt Maryland USA
| | - M. Sarantos
- Heliophysics Science Division; NASA GSFC; Greenbelt Maryland USA
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Sitnov MI, Tsyganenko NA, Ukhorskiy AY, Brandt PC. Dynamical data-based modeling of the storm-time geomagnetic field with enhanced spatial resolution. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007ja013003] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- M. I. Sitnov
- Applied Physics Laboratory; Johns Hopkins University; Laurel Maryland USA
| | - N. A. Tsyganenko
- Institute of Physics; University of St. Petersburg; St. Petersburg Russia
| | - A. Y. Ukhorskiy
- Applied Physics Laboratory; Johns Hopkins University; Laurel Maryland USA
| | - P. C. Brandt
- Applied Physics Laboratory; Johns Hopkins University; Laurel Maryland USA
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Huang CL, Spence HE, Singer HJ, Tsyganenko NA. A quantitative assessment of empirical magnetic field models at geosynchronous orbit during magnetic storms. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007ja012623] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Chia-Lin Huang
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | - Harlan E. Spence
- Center for Space Physics; Boston University; Boston Massachusetts USA
| | | | - Nikolai A. Tsyganenko
- Department of Terrestrial Physics; University of Saint-Petersburg; Petrodvorets, Saint-Petersburg Russian Federation
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45
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Woodfield EE, Dunlop MW, Holme R, Davies JA, Hapgood MA. A comparison of Cluster magnetic data with the Tsyganenko 2001 model. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006ja012217] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- E. E. Woodfield
- Department of Earth and Ocean Sciences; University of Liverpool; Liverpool U.K
| | - M. W. Dunlop
- Space Science and Technology Department; Rutherford Appleton Laboratory; Chilton U.K
| | - R. Holme
- Department of Earth and Ocean Sciences; University of Liverpool; Liverpool U.K
| | - J. A. Davies
- Space Science and Technology Department; Rutherford Appleton Laboratory; Chilton U.K
| | - M. A. Hapgood
- Space Science and Technology Department; Rutherford Appleton Laboratory; Chilton U.K
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46
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Tsyganenko NA, Sitnov MI. Magnetospheric configurations from a high-resolution data-based magnetic field model. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2007ja012260] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- N. A. Tsyganenko
- Universities Space Research Association and Space Weather Laboratory; NASA Goddard Space Flight Center; Greenbelt MD USA
| | - M. I. Sitnov
- Institute for Research in Electronics and Applied Physics; University of Maryland; College Park MD USA
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47
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Zhang J, Liemohn MW, De Zeeuw DL, Borovsky JE, Ridley AJ, Toth G, Sazykin S, Thomsen MF, Kozyra JU, Gombosi TI, Wolf RA. Understanding storm-time ring current development through data-model comparisons of a moderate storm. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006ja011846] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jichun Zhang
- Center for Space Environment Modeling; University of Michigan; Ann Arbor Michigan USA
| | - Michael W. Liemohn
- Center for Space Environment Modeling; University of Michigan; Ann Arbor Michigan USA
| | - Darren L. De Zeeuw
- Center for Space Environment Modeling; University of Michigan; Ann Arbor Michigan USA
| | | | - Aaron J. Ridley
- Center for Space Environment Modeling; University of Michigan; Ann Arbor Michigan USA
| | - Gabor Toth
- Center for Space Environment Modeling; University of Michigan; Ann Arbor Michigan USA
| | - Stanislav Sazykin
- Department of Physics and Astronomy; Rice University; Houston Texas USA
| | | | - Janet U. Kozyra
- Center for Space Environment Modeling; University of Michigan; Ann Arbor Michigan USA
| | - Tamas I. Gombosi
- Center for Space Environment Modeling; University of Michigan; Ann Arbor Michigan USA
| | - Richard A. Wolf
- Department of Physics and Astronomy; Rice University; Houston Texas USA
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48
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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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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49
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Ukhorskiy AY, Anderson BJ, Brandt PC, Tsyganenko NA. Storm time evolution of the outer radiation belt: Transport and losses. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006ja011690] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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50
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Pulkkinen TI, Ganushkina NY, Tanskanen EI, Kubyshkina M, Reeves GD, Thomsen MF, Russell CT, Singer HJ, Slavin JA, Gjerloev J. Magnetospheric current systems during stormtime sawtooth events. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006ja011627] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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