Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS)
Abstract Energetic (greater than tens of keV) magnetospheric particle escape into the magnetosheath occurs commonly, irrespective of conditions that engender reconnection and boundary‐normal magnetic fields. A signature observed by the Magnetospheric Multiscale (MMS) mission, simultaneous monohemisp...
Saved in:
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2016-06-01
|
| Series: | Geophysical Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/2016GL068689 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850274972946137088 |
|---|---|
| author | I. J. Cohen B. H. Mauk B. J. Anderson J. H. Westlake D. G. Sibeck B. L. Giles C. J. Pollock D. L. Turner J. F. Fennell J. B. Blake J. H. Clemmons A. N. Jaynes D. N. Baker J. V. Craft H. E. Spence J. T. Niehof G. D. Reeves R. B. Torbert C. T. Russell R. J. Strangeway W. Magnes K. J. Trattner S. A. Fuselier J. L. Burch |
| author_facet | I. J. Cohen B. H. Mauk B. J. Anderson J. H. Westlake D. G. Sibeck B. L. Giles C. J. Pollock D. L. Turner J. F. Fennell J. B. Blake J. H. Clemmons A. N. Jaynes D. N. Baker J. V. Craft H. E. Spence J. T. Niehof G. D. Reeves R. B. Torbert C. T. Russell R. J. Strangeway W. Magnes K. J. Trattner S. A. Fuselier J. L. Burch |
| author_sort | I. J. Cohen |
| collection | DOAJ |
| description | Abstract Energetic (greater than tens of keV) magnetospheric particle escape into the magnetosheath occurs commonly, irrespective of conditions that engender reconnection and boundary‐normal magnetic fields. A signature observed by the Magnetospheric Multiscale (MMS) mission, simultaneous monohemispheric streaming of multiple species (electrons, H+, Hen+), is reported here as unexpectedly common in the dayside, dusk quadrant of the magnetosheath even though that region is thought to be drift‐shadowed from energetic electrons. This signature is sometimes part of a pitch angle distribution evolving from symmetric in the magnetosphere, to asymmetric approaching the magnetopause, to monohemispheric streaming in the magnetosheath. While monohemispheric streaming in the magnetosheath may be possible without a boundary‐normal magnetic field, the additional pitch angle depletion, particularly of electrons, on the magnetospheric side requires one. Observations of this signature in the dayside dusk sector imply that the static picture of magnetospheric drift‐shadowing is inappropriate for energetic particle dynamics in the outer magnetosphere. |
| format | Article |
| id | doaj-art-48ddeb92ebc048db9df80e2a4dc2675e |
| institution | OA Journals |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2016-06-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geophysical Research Letters |
| spelling | doaj-art-48ddeb92ebc048db9df80e2a4dc2675e2025-08-20T01:50:59ZengWileyGeophysical Research Letters0094-82761944-80072016-06-0143125960596810.1002/2016GL068689Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS)I. J. Cohen0B. H. Mauk1B. J. Anderson2J. H. Westlake3D. G. Sibeck4B. L. Giles5C. J. Pollock6D. L. Turner7J. F. Fennell8J. B. Blake9J. H. Clemmons10A. N. Jaynes11D. N. Baker12J. V. Craft13H. E. Spence14J. T. Niehof15G. D. Reeves16R. B. Torbert17C. T. Russell18R. J. Strangeway19W. Magnes20K. J. Trattner21S. A. Fuselier22J. L. Burch23The Johns Hopkins University Applied Physics Laboratory Laurel Maryland USAThe Johns Hopkins University Applied Physics Laboratory Laurel Maryland USAThe Johns Hopkins University Applied Physics Laboratory Laurel Maryland USAThe Johns Hopkins University Applied Physics Laboratory Laurel Maryland USANASA Goddard Space Flight Center Greenbelt Maryland USANASA Goddard Space Flight Center Greenbelt Maryland USANASA Goddard Space Flight Center Greenbelt Maryland USAAerospace Corporation El Segundo California USAAerospace Corporation El Segundo California USAAerospace Corporation El Segundo California USAAerospace Corporation El Segundo California USALASP University of Colorado Boulder Boulder Colorado USALASP University of Colorado Boulder Boulder Colorado USALASP University of Colorado Boulder Boulder Colorado USASpace Science Center University of New Hampshire Durham New Hampshire USASpace Science Center University of New Hampshire Durham New Hampshire USALos Alamos National Laboratory Los Alamos New Mexico USASpace Science Center University of New Hampshire Durham New Hampshire USAUniversity of California Los Angeles California USAUniversity of California Los Angeles California USASpace Research Institute Austrian Academy of Sciences Graz AustriaLASP University of Colorado Boulder Boulder Colorado USASouthwest Research Institute San Antonio Texas USASouthwest Research Institute San Antonio Texas USAAbstract Energetic (greater than tens of keV) magnetospheric particle escape into the magnetosheath occurs commonly, irrespective of conditions that engender reconnection and boundary‐normal magnetic fields. A signature observed by the Magnetospheric Multiscale (MMS) mission, simultaneous monohemispheric streaming of multiple species (electrons, H+, Hen+), is reported here as unexpectedly common in the dayside, dusk quadrant of the magnetosheath even though that region is thought to be drift‐shadowed from energetic electrons. This signature is sometimes part of a pitch angle distribution evolving from symmetric in the magnetosphere, to asymmetric approaching the magnetopause, to monohemispheric streaming in the magnetosheath. While monohemispheric streaming in the magnetosheath may be possible without a boundary‐normal magnetic field, the additional pitch angle depletion, particularly of electrons, on the magnetospheric side requires one. Observations of this signature in the dayside dusk sector imply that the static picture of magnetospheric drift‐shadowing is inappropriate for energetic particle dynamics in the outer magnetosphere.https://doi.org/10.1002/2016GL068689energetic particle escapemagnetopausemagnetic reconnectionMMSmagnetosheath |
| spellingShingle | I. J. Cohen B. H. Mauk B. J. Anderson J. H. Westlake D. G. Sibeck B. L. Giles C. J. Pollock D. L. Turner J. F. Fennell J. B. Blake J. H. Clemmons A. N. Jaynes D. N. Baker J. V. Craft H. E. Spence J. T. Niehof G. D. Reeves R. B. Torbert C. T. Russell R. J. Strangeway W. Magnes K. J. Trattner S. A. Fuselier J. L. Burch Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS) Geophysical Research Letters energetic particle escape magnetopause magnetic reconnection MMS magnetosheath |
| title | Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS) |
| title_full | Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS) |
| title_fullStr | Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS) |
| title_full_unstemmed | Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS) |
| title_short | Observations of energetic particle escape at the magnetopause: Early results from the MMS Energetic Ion Spectrometer (EIS) |
| title_sort | observations of energetic particle escape at the magnetopause early results from the mms energetic ion spectrometer eis |
| topic | energetic particle escape magnetopause magnetic reconnection MMS magnetosheath |
| url | https://doi.org/10.1002/2016GL068689 |
| work_keys_str_mv | AT ijcohen observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT bhmauk observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT bjanderson observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT jhwestlake observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT dgsibeck observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT blgiles observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT cjpollock observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT dlturner observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT jffennell observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT jbblake observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT jhclemmons observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT anjaynes observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT dnbaker observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT jvcraft observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT hespence observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT jtniehof observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT gdreeves observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT rbtorbert observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT ctrussell observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT rjstrangeway observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT wmagnes observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT kjtrattner observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT safuselier observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis AT jlburch observationsofenergeticparticleescapeatthemagnetopauseearlyresultsfromthemmsenergeticionspectrometereis |