MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets
Abstract We investigate the kinetic structure of electron‐scale current sheets found in the vicinity of the magnetopause and embedded in the magnetosheath within the reconnection exhaust. A new technique for computing terms of the Vlasov equation using Magnetospheric Multiscale (MMS) measurements is...
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| Format: | Article |
| Language: | English |
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Wiley
2019-07-01
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| Series: | Geophysical Research Letters |
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| Online Access: | https://doi.org/10.1029/2019GL083549 |
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| author | J. R. Shuster D. J. Gershman L.‐J. Chen S. Wang N. Bessho J. C. Dorelli D. E. daSilva B. L. Giles W. R. Paterson R. E. Denton S. J. Schwartz C. Norgren V. Wilder P. A. Cassak M. Swisdak V. Uritsky C. Schiff A. C. Rager S. Smith L. A. Avanov A. F. Viñas |
| author_facet | J. R. Shuster D. J. Gershman L.‐J. Chen S. Wang N. Bessho J. C. Dorelli D. E. daSilva B. L. Giles W. R. Paterson R. E. Denton S. J. Schwartz C. Norgren V. Wilder P. A. Cassak M. Swisdak V. Uritsky C. Schiff A. C. Rager S. Smith L. A. Avanov A. F. Viñas |
| author_sort | J. R. Shuster |
| collection | DOAJ |
| description | Abstract We investigate the kinetic structure of electron‐scale current sheets found in the vicinity of the magnetopause and embedded in the magnetosheath within the reconnection exhaust. A new technique for computing terms of the Vlasov equation using Magnetospheric Multiscale (MMS) measurements is presented and applied to study phase space density gradients and the kinetic origins of the electron pressure divergence found within these current sheets. Crescent‐shaped structures in ∇⊥2fe give rise to bipolar and quadrupolar signatures in v·∇fe measured near the maximum ∇·Pe inside the current layers. The current density perpendicular to the magnetic field is strong (J⊥∼2 μA/m2), and the thickness of the current layers ranges from 3 to 5 electron inertial lengths. The electron flows supporting the current layers mainly result from the combination of E×B and diamagnetic drifts. We find nonzero J·E′ within the current sheets even though they are observed apart from typical diffusion region signatures. |
| format | Article |
| id | doaj-art-19e79a1322a54ba88bb9b693fe980e73 |
| institution | OA Journals |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2019-07-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geophysical Research Letters |
| spelling | doaj-art-19e79a1322a54ba88bb9b693fe980e732025-08-20T02:33:55ZengWileyGeophysical Research Letters0094-82761944-80072019-07-0146147862787210.1029/2019GL083549MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current SheetsJ. R. Shuster0D. J. Gershman1L.‐J. Chen2S. Wang3N. Bessho4J. C. Dorelli5D. E. daSilva6B. L. Giles7W. R. Paterson8R. E. Denton9S. J. Schwartz10C. Norgren11V. Wilder12P. A. Cassak13M. Swisdak14V. Uritsky15C. Schiff16A. C. Rager17S. Smith18L. A. Avanov19A. F. Viñas20Department of Astronomy University of Maryland College Park MD USANASA Goddard Space Flight Center Greenbelt MD USANASA Goddard Space Flight Center Greenbelt MD USADepartment of Astronomy University of Maryland College Park MD USADepartment of Astronomy University of Maryland College Park MD USANASA Goddard Space Flight Center Greenbelt MD USANASA Goddard Space Flight Center Greenbelt MD USANASA Goddard Space Flight Center Greenbelt MD USANASA Goddard Space Flight Center Greenbelt MD USADepartment of Physics and Astronomy Dartmouth College Hanover NH USALaboratory for Atmospheric and Space Physics University of Colorado Boulder Boulder CO USABirkeland Centre for Space Science, Department of Physics and Technology University of Bergen Bergen NorwayLaboratory for Atmospheric and Space Physics University of Colorado Boulder Boulder CO USADepartment of Physics and Astronomy West Virginia University Morgantown WV USAInstitute for Research in Electronics and Applied Physics University of Maryland College Park MD USANASA Goddard Space Flight Center Greenbelt MD USANASA Goddard Space Flight Center Greenbelt MD USANASA Goddard Space Flight Center Greenbelt MD USANASA Goddard Space Flight Center Greenbelt MD USADepartment of Astronomy University of Maryland College Park MD USANASA Goddard Space Flight Center Greenbelt MD USAAbstract We investigate the kinetic structure of electron‐scale current sheets found in the vicinity of the magnetopause and embedded in the magnetosheath within the reconnection exhaust. A new technique for computing terms of the Vlasov equation using Magnetospheric Multiscale (MMS) measurements is presented and applied to study phase space density gradients and the kinetic origins of the electron pressure divergence found within these current sheets. Crescent‐shaped structures in ∇⊥2fe give rise to bipolar and quadrupolar signatures in v·∇fe measured near the maximum ∇·Pe inside the current layers. The current density perpendicular to the magnetic field is strong (J⊥∼2 μA/m2), and the thickness of the current layers ranges from 3 to 5 electron inertial lengths. The electron flows supporting the current layers mainly result from the combination of E×B and diamagnetic drifts. We find nonzero J·E′ within the current sheets even though they are observed apart from typical diffusion region signatures.https://doi.org/10.1029/2019GL083549Vlasov equationthin current sheetselectron pressure divergenceMagnetospheric Multiscaleenergy conversionkinetic plasma physics |
| spellingShingle | J. R. Shuster D. J. Gershman L.‐J. Chen S. Wang N. Bessho J. C. Dorelli D. E. daSilva B. L. Giles W. R. Paterson R. E. Denton S. J. Schwartz C. Norgren V. Wilder P. A. Cassak M. Swisdak V. Uritsky C. Schiff A. C. Rager S. Smith L. A. Avanov A. F. Viñas MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets Geophysical Research Letters Vlasov equation thin current sheets electron pressure divergence Magnetospheric Multiscale energy conversion kinetic plasma physics |
| title | MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets |
| title_full | MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets |
| title_fullStr | MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets |
| title_full_unstemmed | MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets |
| title_short | MMS Measurements of the Vlasov Equation: Probing the Electron Pressure Divergence Within Thin Current Sheets |
| title_sort | mms measurements of the vlasov equation probing the electron pressure divergence within thin current sheets |
| topic | Vlasov equation thin current sheets electron pressure divergence Magnetospheric Multiscale energy conversion kinetic plasma physics |
| url | https://doi.org/10.1029/2019GL083549 |
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